CA1276668C - Bimetal strip - Google Patents
Bimetal stripInfo
- Publication number
- CA1276668C CA1276668C CA000555415A CA555415A CA1276668C CA 1276668 C CA1276668 C CA 1276668C CA 000555415 A CA000555415 A CA 000555415A CA 555415 A CA555415 A CA 555415A CA 1276668 C CA1276668 C CA 1276668C
- Authority
- CA
- Canada
- Prior art keywords
- heating resistor
- insulating body
- contact
- electrical heating
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H37/00—Thermally-actuated switches
- H01H37/02—Details
- H01H37/32—Thermally-sensitive members
- H01H37/52—Thermally-sensitive members actuated due to deflection of bimetallic element
- H01H37/54—Thermally-sensitive members actuated due to deflection of bimetallic element wherein the bimetallic element is inherently snap acting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/50—Means for increasing contact pressure, preventing vibration of contacts, holding contacts together after engagement, or biasing contacts to the open position
- H01H1/504—Means for increasing contact pressure, preventing vibration of contacts, holding contacts together after engagement, or biasing contacts to the open position by thermal means
Abstract
ABSTRACT OF THE DISCLOSURE
A bimetal switch has an insulating base on which a contact spring is arranged, this contact spring having at its unattached end a moving contact. In its centre area, the contact spring supports the bimetal element that actuates it. A fixed contact that works in conjunction with the moving contact is arranged on the insulating base and the heating resistor is installed beneath the centre area of the contact spring. In order to develop a bimetal switch of this kind such that it is simpler to produce and at the same time operates more effectively, the heating resistor is a foil resistor that is arranged on that side of the insulating base that faces the contact spring so as to be flat and in thermal contact with the base, this then forming a laminated body with the insulating base.
A bimetal switch has an insulating base on which a contact spring is arranged, this contact spring having at its unattached end a moving contact. In its centre area, the contact spring supports the bimetal element that actuates it. A fixed contact that works in conjunction with the moving contact is arranged on the insulating base and the heating resistor is installed beneath the centre area of the contact spring. In order to develop a bimetal switch of this kind such that it is simpler to produce and at the same time operates more effectively, the heating resistor is a foil resistor that is arranged on that side of the insulating base that faces the contact spring so as to be flat and in thermal contact with the base, this then forming a laminated body with the insulating base.
Description
1;;~7~
The present invention relates to a bimetal switch.
German utility patent G 86 17 033.3 describes a bimetal switch that consists essentially o~ a flat rectangular body of insulating material to which a plurality of electrical contact connecting lugs are connected. ~ne side of the insulating body supports a contact spring that has a moving contact at its unattached end. The bimetal 1~ element is attached in the central area of the contact ; spring, and this determines the switch position of the contact spring, depending on whether it is curved in a convex or a concave shape (in reference to the relative position to the insulating body). A fixed contact that works in con~unction with the moving contact is also attached to the insulating body. The fixed contact is connected electrically with the fixed end of the moving contact through a heating resistor that is arranged beneath the contact spring, this being short circuited when the bimetal switch is closed and conducts current only when the contact spring is open.
This bimetal switch is disadvantageous, in that the insulating body has to be provided wlth a recess for 25 arranging and contacting the reslstor, sald recess then ; accommodating the resistor. The resistor is provided in the form of a block-shaped PTC resistor that is held between two spring elements that act on and contact this on its upper and lower sides. In addition,, a large number of individual 30 elements have to be installed in their final position before the rivets that hold the individual elements together can be installed. This entails a very high level of expenditure for machinery in the event that the switch is to be produced B
in an automated process. ~urthermore, because of its relatively complex construction, a switch of this kind is sensitive and not entirely satisfactory as regards the reciprocity of its switching behaviour.
:: 5 :~ Thermal relays are also know, and these incorporate a plurality of resistors that can be connected to each other by various ways and means, which means that the know thermal relay can be used in a variety of 1() applications, The present invention provides a bimetal switch that is simpler to produce and is capable of improved performance.
~ ccording to the present invention there is provided a bimetal switch comprising, as the.onl~ support member therein, an insulating body having a flat side, a plurality of electrical connectors supported on said zo insulating body, an electrical heating resistor in direct : thermal relation with said insulating body and disposed on said flat side thereof in electrical continuity with said plurality of electrical connectors, and a contact spring having one fixed contact at one end thereof secured to said insulating body and a second end bearing a moving contact, said insulating body supporting a second fixed contact in registry wlth said movlng contact for engagernent therewith upon movement thereof, and a bimetal element supported on sald contact spring and adapted to move said contact spring responslvely to heat generated by sald electrical heatlng reslstor.
In a partlcularly deslrable embodlment thereof , ~27~668 the invention provides a bimetal switch comprising, as the onlv suPport memb~e~r therein, an insulating body fully planar in its exPanse and having first and second opposed flat sides, a plurality of electrical connectors supported on said insulating body first flat side, an electrical heating resistor in direct thermal relation with said insulating body and disposed on said first flat side thereof in electrical continuity with said plurality of electrical connectors, and a contact spring having one fixed contact at one end thereof secured to said second flat side of said insulating body and a second end bearing a moving contact, said insulating body supporting a second fixed contact for engagement therewith upon movement thereof, and a bimetal element supported on said contact spring and adapted to move 1~ said contact spring responsively to heat generated by said electrical heating resistor.
The basic concept of the present invention is that at least one heating resistor is not shaped as a resistor that has to be installed and secured individually, but that it is installed on the side of the insulating body that supports it, that faces towards or away from the contact spring, in direct thermal contact with the insulating body.
If the heating resistor is in particular, as a film resistor 25 and preferably arranged flat on one flat sides of the insulating body then, together with the insulatlng body, it forms a laminated body that, from the commercial point of view, can be very easily prefabricated.
The insulating body, with the heating resistor attached directly to it, can be upgraded in a relatively simple manner to become a bimetal switch in a variety of forms, used for a variety of functions. As an example, one :
The present invention relates to a bimetal switch.
German utility patent G 86 17 033.3 describes a bimetal switch that consists essentially o~ a flat rectangular body of insulating material to which a plurality of electrical contact connecting lugs are connected. ~ne side of the insulating body supports a contact spring that has a moving contact at its unattached end. The bimetal 1~ element is attached in the central area of the contact ; spring, and this determines the switch position of the contact spring, depending on whether it is curved in a convex or a concave shape (in reference to the relative position to the insulating body). A fixed contact that works in con~unction with the moving contact is also attached to the insulating body. The fixed contact is connected electrically with the fixed end of the moving contact through a heating resistor that is arranged beneath the contact spring, this being short circuited when the bimetal switch is closed and conducts current only when the contact spring is open.
This bimetal switch is disadvantageous, in that the insulating body has to be provided wlth a recess for 25 arranging and contacting the reslstor, sald recess then ; accommodating the resistor. The resistor is provided in the form of a block-shaped PTC resistor that is held between two spring elements that act on and contact this on its upper and lower sides. In addition,, a large number of individual 30 elements have to be installed in their final position before the rivets that hold the individual elements together can be installed. This entails a very high level of expenditure for machinery in the event that the switch is to be produced B
in an automated process. ~urthermore, because of its relatively complex construction, a switch of this kind is sensitive and not entirely satisfactory as regards the reciprocity of its switching behaviour.
:: 5 :~ Thermal relays are also know, and these incorporate a plurality of resistors that can be connected to each other by various ways and means, which means that the know thermal relay can be used in a variety of 1() applications, The present invention provides a bimetal switch that is simpler to produce and is capable of improved performance.
~ ccording to the present invention there is provided a bimetal switch comprising, as the.onl~ support member therein, an insulating body having a flat side, a plurality of electrical connectors supported on said zo insulating body, an electrical heating resistor in direct : thermal relation with said insulating body and disposed on said flat side thereof in electrical continuity with said plurality of electrical connectors, and a contact spring having one fixed contact at one end thereof secured to said insulating body and a second end bearing a moving contact, said insulating body supporting a second fixed contact in registry wlth said movlng contact for engagernent therewith upon movement thereof, and a bimetal element supported on sald contact spring and adapted to move said contact spring responslvely to heat generated by sald electrical heatlng reslstor.
In a partlcularly deslrable embodlment thereof , ~27~668 the invention provides a bimetal switch comprising, as the onlv suPport memb~e~r therein, an insulating body fully planar in its exPanse and having first and second opposed flat sides, a plurality of electrical connectors supported on said insulating body first flat side, an electrical heating resistor in direct thermal relation with said insulating body and disposed on said first flat side thereof in electrical continuity with said plurality of electrical connectors, and a contact spring having one fixed contact at one end thereof secured to said second flat side of said insulating body and a second end bearing a moving contact, said insulating body supporting a second fixed contact for engagement therewith upon movement thereof, and a bimetal element supported on said contact spring and adapted to move 1~ said contact spring responsively to heat generated by said electrical heating resistor.
The basic concept of the present invention is that at least one heating resistor is not shaped as a resistor that has to be installed and secured individually, but that it is installed on the side of the insulating body that supports it, that faces towards or away from the contact spring, in direct thermal contact with the insulating body.
If the heating resistor is in particular, as a film resistor 25 and preferably arranged flat on one flat sides of the insulating body then, together with the insulatlng body, it forms a laminated body that, from the commercial point of view, can be very easily prefabricated.
The insulating body, with the heating resistor attached directly to it, can be upgraded in a relatively simple manner to become a bimetal switch in a variety of forms, used for a variety of functions. As an example, one :
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heating resistor can be used as a self-holding heating resistor, if the bimetal switch is one with a self-holding feature. If, for example, the bimetal element is so arranged that the switch opens when the bimetal strip is cold and is closed when the bimetal strip is heated, the switch can be used as a temperature monitoring switch that interrupts a heating-current circuit, for example, by means of a switching element that is incorporated after it.
u In particular, the heating resistor can be a thin-foil resistor or as a thick-foil resistor, it being essential in each case that, together wlth the insulating body, it forms a laminated body that can be prefabricated on a commercial basis (also as an NTC or as a PTC).
It is particularly advantageous if a plurality of heating resistors that form a laminated body together with the insulating body is provided, these being applied to the insulating body together during the production process and 20 can then be separated from each other subsequently by a separating cut. It is~ however, also possible to apply the two insulating foils together through a mask.
In an advanta~eous manner, the additional heating resistor is shorter than the first heating resistor and the connectors of these two heating resistors run parallel to each other and at right angles to the longitudinal dlrection o~ the heating resistors. This results ln an arrangement of the heating resistors and the associated connector elements in the form of two U-shapes, one within the other, whlch saves a great deal of space and which is advantageous from th0 assembly point of view when the switch is used. A
switch that is configured in this way can, for example, be ., ~X76~68 soldered onto a circuit board, when the switch surfaces are perpendicular to the surface of the circuit board. when tis is done, it is preferred that the connectors protrude beyond one edge of the insulating body and these can be inserted into the circuit board very conveniently during assembly.
In order to further minimize the size of the switches i~ is also possible to arrange one resistor on the slde of the insulating body that is closest to the contact spring and the other resistor on the side of the insulating body that is furthest from the contact spring.
In an advantageous manner the resistor foils extend into the area of the associated retaining rivets, which pass through the insulating body. One of the retaining rivets forms the fixed contact and serves simultaneously as a retainer for the first electrical connector, whilst the other retaining rivet holds the fixed end of the contact springs and holds the second electrical contact. The electrical contacts are flat plugs or lugs 20 that protrude on both sides from the insulating body, or the soldering tags discussed above.
In a further embodiment of the present invention the area of the heating resistor or the sum of the areas of 25 the heating resistors is greater than the area of the bimetal element. Suitably the thickness of the heating resistors configured as thin-foil resistors amounts to approximately 2-20 microns. Desirably the heating resistors have an output of approximately 0.5W to 15W, ln partlcular 30 between 2W and 5W. Sultably the heatlng resistors are applied to the side of the insulating by vapor deposition sputterlng, by lmpresslon, or by eplthltactlc growth, or are applied as a paste-like substance. Desirably each heating '"' B
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resistor is a thick-foil resistor that is connected permanently and so as to be thermally conductive to the surface of the insulating body that bears it, which are favourable from the design and function point of view.
In a further embodirnent of the present invention the heating resistor or at least one of the heating resistors is a PTC resistor. Suitably the PTC resistor is cemented, soldered, or welded to the flat side of the insulating body and/or a contact layer arranged between so as to be thermally and electrically conductive or so as to be a thermal form fit.
These embodiments of the bimetal switch according to the present invention are advantageous for those cases in which various applications, which is to say, in particular, differing temperature ranges and/or differing voltage ranges, are to be detected with one and the same switch, and 20 switching behaviours that are as reproducible and the same as possible are to be achieved. In this regard, temperature ranges between -20C and ~80C and voltage ranges from approximately 186 volts to 242 volts are to be understood, for example.
~ special application of the blmetal switch according to the present invention, in its use as a power divider. In a particular embodiment of the present invention the bimetal elernent is installed in the centre 30 area of the compact spring in a reversed position, such that the switch is open when cold, and closed when hot.
It has been seen from the prior art that in ' :
heating resistor can be used as a self-holding heating resistor, if the bimetal switch is one with a self-holding feature. If, for example, the bimetal element is so arranged that the switch opens when the bimetal strip is cold and is closed when the bimetal strip is heated, the switch can be used as a temperature monitoring switch that interrupts a heating-current circuit, for example, by means of a switching element that is incorporated after it.
u In particular, the heating resistor can be a thin-foil resistor or as a thick-foil resistor, it being essential in each case that, together wlth the insulating body, it forms a laminated body that can be prefabricated on a commercial basis (also as an NTC or as a PTC).
It is particularly advantageous if a plurality of heating resistors that form a laminated body together with the insulating body is provided, these being applied to the insulating body together during the production process and 20 can then be separated from each other subsequently by a separating cut. It is~ however, also possible to apply the two insulating foils together through a mask.
In an advanta~eous manner, the additional heating resistor is shorter than the first heating resistor and the connectors of these two heating resistors run parallel to each other and at right angles to the longitudinal dlrection o~ the heating resistors. This results ln an arrangement of the heating resistors and the associated connector elements in the form of two U-shapes, one within the other, whlch saves a great deal of space and which is advantageous from th0 assembly point of view when the switch is used. A
switch that is configured in this way can, for example, be ., ~X76~68 soldered onto a circuit board, when the switch surfaces are perpendicular to the surface of the circuit board. when tis is done, it is preferred that the connectors protrude beyond one edge of the insulating body and these can be inserted into the circuit board very conveniently during assembly.
In order to further minimize the size of the switches i~ is also possible to arrange one resistor on the slde of the insulating body that is closest to the contact spring and the other resistor on the side of the insulating body that is furthest from the contact spring.
In an advantageous manner the resistor foils extend into the area of the associated retaining rivets, which pass through the insulating body. One of the retaining rivets forms the fixed contact and serves simultaneously as a retainer for the first electrical connector, whilst the other retaining rivet holds the fixed end of the contact springs and holds the second electrical contact. The electrical contacts are flat plugs or lugs 20 that protrude on both sides from the insulating body, or the soldering tags discussed above.
In a further embodiment of the present invention the area of the heating resistor or the sum of the areas of 25 the heating resistors is greater than the area of the bimetal element. Suitably the thickness of the heating resistors configured as thin-foil resistors amounts to approximately 2-20 microns. Desirably the heating resistors have an output of approximately 0.5W to 15W, ln partlcular 30 between 2W and 5W. Sultably the heatlng resistors are applied to the side of the insulating by vapor deposition sputterlng, by lmpresslon, or by eplthltactlc growth, or are applied as a paste-like substance. Desirably each heating '"' B
~ 7~
resistor is a thick-foil resistor that is connected permanently and so as to be thermally conductive to the surface of the insulating body that bears it, which are favourable from the design and function point of view.
In a further embodirnent of the present invention the heating resistor or at least one of the heating resistors is a PTC resistor. Suitably the PTC resistor is cemented, soldered, or welded to the flat side of the insulating body and/or a contact layer arranged between so as to be thermally and electrically conductive or so as to be a thermal form fit.
These embodiments of the bimetal switch according to the present invention are advantageous for those cases in which various applications, which is to say, in particular, differing temperature ranges and/or differing voltage ranges, are to be detected with one and the same switch, and 20 switching behaviours that are as reproducible and the same as possible are to be achieved. In this regard, temperature ranges between -20C and ~80C and voltage ranges from approximately 186 volts to 242 volts are to be understood, for example.
~ special application of the blmetal switch according to the present invention, in its use as a power divider. In a particular embodiment of the present invention the bimetal elernent is installed in the centre 30 area of the compact spring in a reversed position, such that the switch is open when cold, and closed when hot.
It has been seen from the prior art that in ' :
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~ ' ;6~
specific applications power dividing diodes with equivalent half-wave power division are no longer reliable since this loads the network asymetrically, which is undesirable. This is avoided by the use of the bimetal switch according to the present invention as a power divider, which is to say that the bimetal switch represents an ldeal replacement for power dividing diodes.
On the basis of the above embodiment of the ~-~ bimetal switch one obtains a curvature of the bimetal strip that is reversed for practical purposes, which leads to the fact that the switch is open when cold and closed when hot.
In the open state the heating resistor is efEective and after a specific duty cycle-time this closes the switch, 1~ which means that the heating resistor itself becomes cold again, although the load is switched on. If, on the other hand, the heating resistor has cooled down to the point that the bimetal strip has also become cold again, the switch will open once again which means that the load is switched off an the whole cycle can begin again from the start. As as example, the cycling behaviour of this type of power division can be ad~usted by the sequential switch-on and switch-off procedures with the help of a variation of the resistance value of the heating resistor. However, lt is 25 also possible to arrive at the desired cycling behaviour with the help of various bimetal discs, wlth the resistance value of the heating resistor remaining constant, and ln particular to vary this cycllng behaviour in the desired manner.
Alternatively, the cycling behaviour can also be adjusted in that the substrate, which is to say the . . .
'~; 'i`' ~2766~13 insulating body, can be made relatively large, which is to say over-dimensioned, which results in a relatively high rate of thermal dissipation, and in that this insulating body is divided into two areas that are connected with each other through a nominal breakpoint, so that a first cycle time can be set for a complete insulating body and a second cycle time, which differs from the first, can be set for an insulating body that has been reduced by the separated area.
1(~
In a further embodiment of the present invention one heating resistor is arranged on the side of the insulating body that is closest to the contact spring and the other heating resistor is arranged on the side of the insulating body that is furthest from the contact spring.
Thus results in a further advantageous use of the bimetal switches according to the present invention in the form of their multiple arrangement on a carrier.
Several advantageous embodiments of the present invention are comprisingly shown in the following drawings:
Figure 1: is a schematic section through a first embodiment of a bimetal switch according to the present invention;
,25 Figure 2; is a schematic plan view in the direction indicated by the arrow A in Figure l;
Figure 3: is a schematic section of a further embodiment of 30 a bimetal switch according to the present invention;
Figure 4: is a schematic section of a third embodiment of a bimetal switch according to the present invention;
~ ' ;6~
specific applications power dividing diodes with equivalent half-wave power division are no longer reliable since this loads the network asymetrically, which is undesirable. This is avoided by the use of the bimetal switch according to the present invention as a power divider, which is to say that the bimetal switch represents an ldeal replacement for power dividing diodes.
On the basis of the above embodiment of the ~-~ bimetal switch one obtains a curvature of the bimetal strip that is reversed for practical purposes, which leads to the fact that the switch is open when cold and closed when hot.
In the open state the heating resistor is efEective and after a specific duty cycle-time this closes the switch, 1~ which means that the heating resistor itself becomes cold again, although the load is switched on. If, on the other hand, the heating resistor has cooled down to the point that the bimetal strip has also become cold again, the switch will open once again which means that the load is switched off an the whole cycle can begin again from the start. As as example, the cycling behaviour of this type of power division can be ad~usted by the sequential switch-on and switch-off procedures with the help of a variation of the resistance value of the heating resistor. However, lt is 25 also possible to arrive at the desired cycling behaviour with the help of various bimetal discs, wlth the resistance value of the heating resistor remaining constant, and ln particular to vary this cycllng behaviour in the desired manner.
Alternatively, the cycling behaviour can also be adjusted in that the substrate, which is to say the . . .
'~; 'i`' ~2766~13 insulating body, can be made relatively large, which is to say over-dimensioned, which results in a relatively high rate of thermal dissipation, and in that this insulating body is divided into two areas that are connected with each other through a nominal breakpoint, so that a first cycle time can be set for a complete insulating body and a second cycle time, which differs from the first, can be set for an insulating body that has been reduced by the separated area.
1(~
In a further embodiment of the present invention one heating resistor is arranged on the side of the insulating body that is closest to the contact spring and the other heating resistor is arranged on the side of the insulating body that is furthest from the contact spring.
Thus results in a further advantageous use of the bimetal switches according to the present invention in the form of their multiple arrangement on a carrier.
Several advantageous embodiments of the present invention are comprisingly shown in the following drawings:
Figure 1: is a schematic section through a first embodiment of a bimetal switch according to the present invention;
,25 Figure 2; is a schematic plan view in the direction indicated by the arrow A in Figure l;
Figure 3: is a schematic section of a further embodiment of 30 a bimetal switch according to the present invention;
Figure 4: is a schematic section of a third embodiment of a bimetal switch according to the present invention;
B
1;~76~6~3 Figures 5 and 6: are front and rear views of a fourth embodiment of a bimetal switch according to the present invention;
Figure 7: is a rear view of a fifth embodiment of a bimetal switch according to the present invention;
Figure 8: is a side view of a bimetal switch in Figure 7;
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Figure 9: is a perspective view of an embodiment of a heating resistor in the form of a PTC resistor;
Figure 10: is a front view of an embodiment of a multiple arrangement of bimetal switches according to the present .invention mounted on a carrier; and Figure 11: is a schematic view of the rear of the carrier of a multiple arrangement in the direction indicated by the 20 arrow B in Figure 10.
The bimetal switch 1 has an insulating body 2 to which is attached a contact spring 3 that has a moving contact 5 at its unattached end 4. A bimetal element 7 on 25 the form of a circular bimetal disc is attached to the central part 6 of the contact spring 5 by clamping elements.
In addltion, a fixed contact 8 on the form of a rivet head is also provided on the insulating body 2. The fixed contact 8 is connected electrically to the moving contact 5 30 when the contacts are in the closed position.
Beneath the centre area 6 a heating resistor on the form of a film resistor is arranged so as to be flat on :
_ 9 _ .
~Z76~6~3 the side of the insulating body that is ad~acent the contact spring 3, and in thermal contact with the insulating body 2 and which with the insulating body 2 forms a laminated body.
In the first embodiment, the hea-ting resistor 9 essentially covers the whole of the side 10 of the body 2 that is closest to the contact spring 3, and can be on the form of a thin-foil resistor. As is also made clear by Figure 1, the foil of the heating resistor 9 out acts both the fixed contact 8 as well as a further rivet 11 that secures the contact spring 3 at its attachment end. Thus the resistor foil of the heating resistor 9 connects the fixed end 12 of the contact spring 3 electrically with the fixed contact 8. Essentially, the resistor foil is of similar thickness over, the whole area of contact with the 15 side 10, and the resistor foil is of a greater area than the area of the contact spring 3, as is indicated by the dashed line ln Figure 2.
Between the fixed end 12 of the contact sprlng 3 20 and the resistor foil (heating resistor 9) there is a metal spacer 13, the thickness of which corresponds essentially to the height of the fixed contact 8. As can be seen from Figure 3, the spacer 13 can be formed by the end of the connector element 14 that is in the form of a flat tab.
25 Ev`en though in Figuxe 1 the resistor foil ~heating resistor 9) is shown as being relatively thick, it is in fact only 2-20 microns thick, and has a heater output of approximately 0.5W to 5W. It can be applied by vapor deposition ;sputtering, imprinting, grown on epidactically or coated on 30as a paste-llke substance. In order to adjust the resistance of the foil that has been applled, an equalizing groove (not shown) can be burnt into the foil transversely B
~Z7~i6~3 to its longitudinal direction by a laser. The insulating body 2 consists of oxide ceramics that possess good thermal conductivity.
In the embodiment shown in Fiyure 3 the heating resistor g consists of a thick-foil resistor that is connected to the surface of the insulating body 2 that supports it so as to be permanently fixed and thermally conductive.
1~
The third embodiment shown in Figure 4 shows a bimetal switch that has the resistor foil 9 on the side of the insulating body 2 that is remote from the contact spring 3. In this switch, it is essential that the foil g and the insulating body 2 be so connected as to possess a high level of thermal conductivity.
In the embodiment shown in Figures 1 and 2 the insulating body 2 is enclosed at its fixed-contact end 15 by a frame-like carrier 16 on the inner side 17 of which opposite the fixed contact 8, there is a reversing cGntact surface 18.
On the side of the insulating body 2 that is opposite the resistor foil (heating resistor 9) there is in the middle area a recess 19 that reduced the thermal inertia of the insulating body 2, and this is surrounded by and edge 21 that contributes to the base area 20 of the switch.
Figures 3 and 4 also show that in the area of the rivets 11, 22, between the surface of the resistor foil and the surface of the rivet and/or the surfaces of the insulating body 2 there is a layer that is extremely ... ,~
~ .
;~ ~27~ B
conductive both thermally and electrically, in the form of a conduc-tive silver foil 23.
In the embodiment shown in ~igures 5 and 6 the insulating body 30 is in the form of a flat rectangular plate that has on its front side 31 the contact spring 32 with the bimetal element 33, and on its rear side 34 has a heating resistor 35 and a further heating resistor 36. The arrangement and contact system of the heating resistor 35 relative to the retaining rivets and the contact spring 32 correspond to the arrangement and the contact system of the heating resistor 9 as in the Figures 1 to 4. The additional heating resistor 36, that is in parallel to the heating resistor 3s on the rear side 34 of the insulating body 30, is not connected to the contact of the contact spring arrangement 32, but has separate connectors, i.e., the soldering tags 37, that are essentially parallel to the connectors for the heating element 35, which are configured as soldering tags 38. Viewed as a whole, the soldering tag-heating resistor arrangements 38-35-38 on the one hand, and 37-36-37~ on the other, form two U-shapes set one inside the other.
As in the case in the embodiment shown in Figures 1-4, the connector elements are connected to the lnsulating body 30 through the rivets 39 and are connected by means of conductive sllver foil sections 40 with the ends of the associated heating resistors 35 or 36, respectively.
The embodiment of a blmetal switch that is shown in Figures 7 and 8 varies from the embodiment shown in Figures 5 and 6 essentially in that the insulating body 52 has a heating resistor 50 that is a PTC resistor on its rear ~27666~3 flat side 53, it being preferred that this PTC resistor be in the form of a cylindrical disc 51, i.e., in the form of a tablet. Two electrical connector elements 54 and 55 are provided on the rear flat side 53 of the insulating body 52 to supply current to this PTC resistor 50, one of these connector elements simultaneously serving to secure the PTC
resistor 50. This connector element 54 is preferably in the form of a clip or clamping spring that has in its upper area two inclined arms 56 with hook-shaped sections 57 at their o ends, by means of which the upper end of the connector element 54 can be hooked over a corresponding edge of the insulating body 52.
The opposite end of this connector element 54 is connected rigidly to the insulating body 52 by means of a . rivet 39. Furthermore, in the area of its clamp or clamping spring this connector element 54 has an area 58 that curves convexly relative to the rear side surface of the insulating body 52 such that when the connector element 54 is secured 20 to the insulating body 52 the PTC resistor 50 can be clamped .beneath this curved area 58, so that it is thus in direct contact on the corresponding flat side 53. The other electrical connector element 5s for the PTC resistor 50 can preferably be configured in an essentially L-shape, with one 25 arm of this connector element forming an lntermediate layer between the surfaces of the PTC resistor 50 and the surface 53 of the insulating body, which face each other, whereas the other arm of the L-shaped connector element that is at rlght angles to this is once agaln connected to the 3~ lnsulating body 52 through a rivet 39.
The direct or practically direct thermal contact of the PTC resistor 50 with the surface 53 of the insulating .
1~_,,r ~X76~i68 body is thus ensured by the clamp or clamping spring-like connector element 54, which presses this PTC resistor 50 onto the insulating body 52 or onto the contact surface of th L-shaped second connector element by.means of its curved section 58. This second electr~cal connector element 53 can however be a conductive silver foil applied to the flat side 53 of the insulating body such that this conductive silver foil serves simultaneously as a contact`and as a means for transferring heat to the ceramic material of the insulating body 52.
Thee construction of a thermal relay is made possible with this heating resistor 50 in the form of a PTC
resistor. With this, differing temperature and/or differing voltage areas can be detected so as to be reproducible.
Figure 10 shows an embodiment of a multiple arrangement of bimetal swi$ches, these being for example, as in Figures 5 and 6 or as in Figures 7 and 8, an insulating carrier 41 being provided in the form of a clrcuit board on which a plurality of bimetal switches or thermal relays can be mounted. To this end, on its surface that is opposite the arrangement of the switches 1 the carrier 41 has conductor strips ~0 and 61 (Figure 11), with which the electrical connections, which is to say the solderlng tags 37. and 38, are connected to the indlvidual switches 1. In particular, there are sockets 62 in the areas of these conductor strips 60 and 61, these extending through the circuit board that forms the carrier and accommodatlng the correspondlng soldering tags 37 and 38 of the swltches 1.
Such a use of bimetal swltches 1 in the form of a multiple arrangement also makes it possible to construct ~2~
complex control processes and/or combine various switches 1 to each other in any combination, for example, openers and/or closer, by which means it is possible, for example, to construct warning lights, switching procedures, and the like.
As is also shown in Figure 11, the conductor strips 60 and 61 are installed on the rear of the carrier 41 such that the heating resistors 35 and 36 are connected in parallel to all the switches 1 that are installed on the carrier 41.
Figures 10 and 11 also show that contacts 42, 43 and 44 are also connected with the plate or with the carrier 41, these contacts being in particular angles and insertable in the corresponding sockets in the plate 41 and being in electrical contact with the conductor strips 60 and 61 so that the whole of the multiple arrangement of bimetal switches connected in parallel can be supplied with current through these contacts 42, 43 and 44.
B
1;~76~6~3 Figures 5 and 6: are front and rear views of a fourth embodiment of a bimetal switch according to the present invention;
Figure 7: is a rear view of a fifth embodiment of a bimetal switch according to the present invention;
Figure 8: is a side view of a bimetal switch in Figure 7;
1(~
Figure 9: is a perspective view of an embodiment of a heating resistor in the form of a PTC resistor;
Figure 10: is a front view of an embodiment of a multiple arrangement of bimetal switches according to the present .invention mounted on a carrier; and Figure 11: is a schematic view of the rear of the carrier of a multiple arrangement in the direction indicated by the 20 arrow B in Figure 10.
The bimetal switch 1 has an insulating body 2 to which is attached a contact spring 3 that has a moving contact 5 at its unattached end 4. A bimetal element 7 on 25 the form of a circular bimetal disc is attached to the central part 6 of the contact spring 5 by clamping elements.
In addltion, a fixed contact 8 on the form of a rivet head is also provided on the insulating body 2. The fixed contact 8 is connected electrically to the moving contact 5 30 when the contacts are in the closed position.
Beneath the centre area 6 a heating resistor on the form of a film resistor is arranged so as to be flat on :
_ 9 _ .
~Z76~6~3 the side of the insulating body that is ad~acent the contact spring 3, and in thermal contact with the insulating body 2 and which with the insulating body 2 forms a laminated body.
In the first embodiment, the hea-ting resistor 9 essentially covers the whole of the side 10 of the body 2 that is closest to the contact spring 3, and can be on the form of a thin-foil resistor. As is also made clear by Figure 1, the foil of the heating resistor 9 out acts both the fixed contact 8 as well as a further rivet 11 that secures the contact spring 3 at its attachment end. Thus the resistor foil of the heating resistor 9 connects the fixed end 12 of the contact spring 3 electrically with the fixed contact 8. Essentially, the resistor foil is of similar thickness over, the whole area of contact with the 15 side 10, and the resistor foil is of a greater area than the area of the contact spring 3, as is indicated by the dashed line ln Figure 2.
Between the fixed end 12 of the contact sprlng 3 20 and the resistor foil (heating resistor 9) there is a metal spacer 13, the thickness of which corresponds essentially to the height of the fixed contact 8. As can be seen from Figure 3, the spacer 13 can be formed by the end of the connector element 14 that is in the form of a flat tab.
25 Ev`en though in Figuxe 1 the resistor foil ~heating resistor 9) is shown as being relatively thick, it is in fact only 2-20 microns thick, and has a heater output of approximately 0.5W to 5W. It can be applied by vapor deposition ;sputtering, imprinting, grown on epidactically or coated on 30as a paste-llke substance. In order to adjust the resistance of the foil that has been applled, an equalizing groove (not shown) can be burnt into the foil transversely B
~Z7~i6~3 to its longitudinal direction by a laser. The insulating body 2 consists of oxide ceramics that possess good thermal conductivity.
In the embodiment shown in Fiyure 3 the heating resistor g consists of a thick-foil resistor that is connected to the surface of the insulating body 2 that supports it so as to be permanently fixed and thermally conductive.
1~
The third embodiment shown in Figure 4 shows a bimetal switch that has the resistor foil 9 on the side of the insulating body 2 that is remote from the contact spring 3. In this switch, it is essential that the foil g and the insulating body 2 be so connected as to possess a high level of thermal conductivity.
In the embodiment shown in Figures 1 and 2 the insulating body 2 is enclosed at its fixed-contact end 15 by a frame-like carrier 16 on the inner side 17 of which opposite the fixed contact 8, there is a reversing cGntact surface 18.
On the side of the insulating body 2 that is opposite the resistor foil (heating resistor 9) there is in the middle area a recess 19 that reduced the thermal inertia of the insulating body 2, and this is surrounded by and edge 21 that contributes to the base area 20 of the switch.
Figures 3 and 4 also show that in the area of the rivets 11, 22, between the surface of the resistor foil and the surface of the rivet and/or the surfaces of the insulating body 2 there is a layer that is extremely ... ,~
~ .
;~ ~27~ B
conductive both thermally and electrically, in the form of a conduc-tive silver foil 23.
In the embodiment shown in ~igures 5 and 6 the insulating body 30 is in the form of a flat rectangular plate that has on its front side 31 the contact spring 32 with the bimetal element 33, and on its rear side 34 has a heating resistor 35 and a further heating resistor 36. The arrangement and contact system of the heating resistor 35 relative to the retaining rivets and the contact spring 32 correspond to the arrangement and the contact system of the heating resistor 9 as in the Figures 1 to 4. The additional heating resistor 36, that is in parallel to the heating resistor 3s on the rear side 34 of the insulating body 30, is not connected to the contact of the contact spring arrangement 32, but has separate connectors, i.e., the soldering tags 37, that are essentially parallel to the connectors for the heating element 35, which are configured as soldering tags 38. Viewed as a whole, the soldering tag-heating resistor arrangements 38-35-38 on the one hand, and 37-36-37~ on the other, form two U-shapes set one inside the other.
As in the case in the embodiment shown in Figures 1-4, the connector elements are connected to the lnsulating body 30 through the rivets 39 and are connected by means of conductive sllver foil sections 40 with the ends of the associated heating resistors 35 or 36, respectively.
The embodiment of a blmetal switch that is shown in Figures 7 and 8 varies from the embodiment shown in Figures 5 and 6 essentially in that the insulating body 52 has a heating resistor 50 that is a PTC resistor on its rear ~27666~3 flat side 53, it being preferred that this PTC resistor be in the form of a cylindrical disc 51, i.e., in the form of a tablet. Two electrical connector elements 54 and 55 are provided on the rear flat side 53 of the insulating body 52 to supply current to this PTC resistor 50, one of these connector elements simultaneously serving to secure the PTC
resistor 50. This connector element 54 is preferably in the form of a clip or clamping spring that has in its upper area two inclined arms 56 with hook-shaped sections 57 at their o ends, by means of which the upper end of the connector element 54 can be hooked over a corresponding edge of the insulating body 52.
The opposite end of this connector element 54 is connected rigidly to the insulating body 52 by means of a . rivet 39. Furthermore, in the area of its clamp or clamping spring this connector element 54 has an area 58 that curves convexly relative to the rear side surface of the insulating body 52 such that when the connector element 54 is secured 20 to the insulating body 52 the PTC resistor 50 can be clamped .beneath this curved area 58, so that it is thus in direct contact on the corresponding flat side 53. The other electrical connector element 5s for the PTC resistor 50 can preferably be configured in an essentially L-shape, with one 25 arm of this connector element forming an lntermediate layer between the surfaces of the PTC resistor 50 and the surface 53 of the insulating body, which face each other, whereas the other arm of the L-shaped connector element that is at rlght angles to this is once agaln connected to the 3~ lnsulating body 52 through a rivet 39.
The direct or practically direct thermal contact of the PTC resistor 50 with the surface 53 of the insulating .
1~_,,r ~X76~i68 body is thus ensured by the clamp or clamping spring-like connector element 54, which presses this PTC resistor 50 onto the insulating body 52 or onto the contact surface of th L-shaped second connector element by.means of its curved section 58. This second electr~cal connector element 53 can however be a conductive silver foil applied to the flat side 53 of the insulating body such that this conductive silver foil serves simultaneously as a contact`and as a means for transferring heat to the ceramic material of the insulating body 52.
Thee construction of a thermal relay is made possible with this heating resistor 50 in the form of a PTC
resistor. With this, differing temperature and/or differing voltage areas can be detected so as to be reproducible.
Figure 10 shows an embodiment of a multiple arrangement of bimetal swi$ches, these being for example, as in Figures 5 and 6 or as in Figures 7 and 8, an insulating carrier 41 being provided in the form of a clrcuit board on which a plurality of bimetal switches or thermal relays can be mounted. To this end, on its surface that is opposite the arrangement of the switches 1 the carrier 41 has conductor strips ~0 and 61 (Figure 11), with which the electrical connections, which is to say the solderlng tags 37. and 38, are connected to the indlvidual switches 1. In particular, there are sockets 62 in the areas of these conductor strips 60 and 61, these extending through the circuit board that forms the carrier and accommodatlng the correspondlng soldering tags 37 and 38 of the swltches 1.
Such a use of bimetal swltches 1 in the form of a multiple arrangement also makes it possible to construct ~2~
complex control processes and/or combine various switches 1 to each other in any combination, for example, openers and/or closer, by which means it is possible, for example, to construct warning lights, switching procedures, and the like.
As is also shown in Figure 11, the conductor strips 60 and 61 are installed on the rear of the carrier 41 such that the heating resistors 35 and 36 are connected in parallel to all the switches 1 that are installed on the carrier 41.
Figures 10 and 11 also show that contacts 42, 43 and 44 are also connected with the plate or with the carrier 41, these contacts being in particular angles and insertable in the corresponding sockets in the plate 41 and being in electrical contact with the conductor strips 60 and 61 so that the whole of the multiple arrangement of bimetal switches connected in parallel can be supplied with current through these contacts 42, 43 and 44.
B
Claims (14)
1. A bimetal switch comprising, as the only support member therein, an insulating body having a flat side, a plurality of electrical connectors supported on said insulating body, an electrical heating resistor in direct thermal relation with said insulating body and disposed on said flat side thereof in electrical continuity with said plurality of electrical connectors, and a contact spring having one fixed contact at one end thereof secured to said insulating body and a second end bearing a moving contact, said insulating body supporting a second fixed contact in registry with said moving contact for engagement therewith upon movement thereof, and a bimetal element supported on said contact spring and adapted to move said contact spring responsively to heat generated by said electrical heating resistor.
2. A bimetal switch as defined in claim 1 wherein said electrical heating resistor connects the fixed contact of said contact spring with said second fixed contact.
3. A bimetal switch as defined in claim 1, further including a second electrical heating resistor disposed in parallel with said first-mentioned electrical heating resistor and in direct thermal relation with said insulating body.
4. A bimetal switch as defined in claim 1, wherein the area of the electrical heating resistor is greater than the area of the bimetal element.
5. A bimetal switch as defined in claim 1, wherein said electrical heating resistor is a thin foil resistor having a thickness of approximately 2-20 microns.
6. A bimetal switch as defined in claim 1, wherein the electrical heating resistor has an output of approximately 0.5w to 15W.
7. A bimetal switch as defined in claim 1, wherein the electrical heating resistor comprises a PTC
resistor.
resistor.
8. A bimetal switch comprising, as the only support member therein an insulating body fully planar in its expanse and having first and second opposed flat sides, a plurality of electrical connectors supported on said insulating body first flat side, and electrical heating resistor in direct thermal relation with said insulating body and disposed on said first flat side thereof in electrical continuity with said plurality of electrical connectors, and a contact spring having one fixed contact at one end thereof secured to said second flat side of said insulating body and a second end bearing a moving contact, said insulating body supporting a second fixed contact on said second flat side in registry with said moving contact for engagement therewith upon movement thereof, and a bimetal element supported on said contact spring and adapted to move said contact spring responsively to heat generated by said electrical heating resistor.
9. A bimetal switch as defined in claim 8 wherein said electrical heating resistor connects the fixed contact of said contact spring with said second fixed contact.
10. A bimetal switch as defined in claim 8, including a second electrical heating resistor disposed in parallel with said first-mentioned electrical heating resistor and in direct thermal relation with said insulating body.
11. A bimetal switch as defined in claim 8, wherein the area of the electrical heating resistor is greater than the area of the bimetal element.
12. A bimetal switch as defined in claim 8 wherein said electrical heating resistor is a thin foil resistor having a thickness of approximately 2-20 microns.
13. A bimetal switch as defined in claim 8, wherein the electrical heating resistor has an output of approximately 0.5W to 15W.
14. A bimetal switch a defined in claim 8, wherein the electrical heating resistor comprises a PTC
resistor.
resistor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3644514.2-34 | 1986-12-24 | ||
| DE19863644514 DE3644514A1 (en) | 1986-12-24 | 1986-12-24 | BIMETAL SWITCH |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1276668C true CA1276668C (en) | 1990-11-20 |
Family
ID=6317249
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000555415A Expired - Lifetime CA1276668C (en) | 1986-12-24 | 1987-12-24 | Bimetal strip |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4862132A (en) |
| EP (1) | EP0272696A3 (en) |
| CA (1) | CA1276668C (en) |
| DE (1) | DE3644514A1 (en) |
Families Citing this family (33)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5182538A (en) * | 1985-11-07 | 1993-01-26 | Limitor Ag | Bimetal thermoswitch |
| DE3842171A1 (en) * | 1988-12-15 | 1990-06-28 | Barlian Reinhold | DELAY RELAY |
| SE9003405D0 (en) * | 1990-10-25 | 1990-10-25 | Backer Elektro Vaerme | ELECTRIC STIRRATOR MEASUREMENT AND TEMPERATURE CIRCUIT |
| JP2585148B2 (en) * | 1991-04-05 | 1997-02-26 | ウチヤ・サーモスタット株式会社 | Thermostat with built-in film heating element |
| DE4206157A1 (en) | 1992-02-28 | 1993-09-16 | Hofsass P | THERMAL SWITCH |
| DE9203559U1 (en) * | 1992-03-17 | 1992-05-21 | Knobel Ag Lichttechnische Komponenten, Ennenda, Ch | |
| JP2585164B2 (en) * | 1992-07-07 | 1997-02-26 | ウチヤ・サーモスタット株式会社 | Thermo protector |
| DE4300909C2 (en) * | 1993-01-15 | 1997-02-06 | Abb Patent Gmbh | Thermal release, especially for a circuit breaker |
| DE4335639A1 (en) * | 1993-10-13 | 1995-04-20 | Eaw Relaistechnik Gmbh | Thermostatic switch having a bimetallic snap-action disc and electrical/thermal prevention of the bimetallic snap-action disc snapping back automatically |
| JP2791383B2 (en) * | 1994-06-10 | 1998-08-27 | ウチヤ・サーモスタット株式会社 | Double safety thermostat |
| DE19507105C1 (en) * | 1995-03-01 | 1996-05-15 | Hofsaes Geb Zeitz Ulrika | Temperature monitor with excess temp. electrical switch |
| DE19514853C2 (en) * | 1995-04-26 | 1997-02-27 | Marcel Hofsaes | Temperature monitor with a bimetal switching mechanism that switches in the event of overtemperature |
| IT1277949B1 (en) * | 1995-12-18 | 1997-11-12 | Texas Instr Control And Manufa | THERMAL ACTUATOR WITH CONSTANT ACTUATION DELAY AS THE AMBIENT TEMPERATURE CHANGES |
| DE19604939C2 (en) * | 1996-02-10 | 1999-12-09 | Marcel Hofsaes | Switch with a temperature-dependent switching mechanism |
| DE19708436C2 (en) * | 1997-03-01 | 1999-08-19 | Hofsaes | Temperature-dependent switch with contact bridge and process for its manufacture |
| DE19727197C2 (en) * | 1997-06-26 | 1999-10-21 | Marcel Hofsaess | Temperature-dependent switch with contact bridge |
| DE19752581C2 (en) * | 1997-11-27 | 1999-12-23 | Marcel Hofsaes | Switch with a temperature-dependent switching mechanism |
| US6191680B1 (en) * | 1998-02-23 | 2001-02-20 | HOFSäSS MARCEL | Switch having a safety element |
| DE19816807C2 (en) * | 1998-04-16 | 2000-06-08 | Thermik Geraetebau Gmbh | Temperature-dependent switch |
| DE19816809C2 (en) * | 1998-04-16 | 2001-10-18 | Thermik Geraetebau Gmbh | Temperature-dependent switch |
| DE19827113C2 (en) * | 1998-06-18 | 2001-11-29 | Marcel Hofsaes | Temperature-dependent switch with current transfer element |
| DE19847209C2 (en) * | 1998-10-13 | 2002-04-25 | Marcel Hofsaes | Switch with an insulating carrier |
| DE19847208C2 (en) * | 1998-10-13 | 2002-05-16 | Marcel Hofsaes | Switch with an insulating carrier |
| JP4471479B2 (en) * | 2000-10-13 | 2010-06-02 | ウチヤ・サーモスタット株式会社 | Thermal protector |
| JP2004014434A (en) * | 2002-06-11 | 2004-01-15 | Uchiya Thermostat Kk | Dc current shut-0ff switch |
| JP2005108585A (en) * | 2003-09-30 | 2005-04-21 | Alps Electric Co Ltd | Thermally-actuated switch |
| US7800477B1 (en) * | 2007-03-20 | 2010-09-21 | Thermtrol Corporation | Thermal protector |
| WO2009095961A1 (en) * | 2008-01-28 | 2009-08-06 | Uchiya Thermostat Co., Ltd. | Thermal protector |
| JP5000540B2 (en) * | 2008-01-31 | 2012-08-15 | 新光電気工業株式会社 | Wiring board with switching function |
| DE112008003792B4 (en) * | 2008-04-10 | 2022-08-04 | Uchlya Thermostat Co., Ltd. | temperature switch |
| CN102007561B (en) * | 2008-04-18 | 2014-07-02 | 泰科电子日本合同会社 | Circuit protection device |
| DE102013108508A1 (en) * | 2013-08-07 | 2015-02-12 | Thermik Gerätebau GmbH | Temperature-dependent switch |
| US10439196B2 (en) * | 2015-12-18 | 2019-10-08 | Bourns, Inc. | Electromechanical circuit breaker |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1401964A (en) * | 1963-07-19 | 1965-06-11 | Otter Controls Ltd | Temperature sensitive electrical switch |
| GB1515356A (en) * | 1976-08-02 | 1978-06-21 | Emi Ltd | Electric switch |
| DE2709175A1 (en) * | 1977-03-03 | 1978-09-07 | Inter Control Koehler Hermann | Thermostat combination mounted on common base plate - supports ceramic resistor by angle bracket with prongs at different levels |
| DE7920923U1 (en) * | 1979-07-21 | 1979-10-25 | Limitor Ag, Zuerich (Schweiz) | Thermal time switch |
| DE3231136C2 (en) * | 1982-08-21 | 1984-08-23 | Limitor AG, 8022 Zürich | Bimetal circuit breaker |
| DE8411838U1 (en) * | 1984-04-14 | 1984-07-26 | Limitor GmbH, 7530 Pforzheim | Bimetal circuit breaker |
-
1986
- 1986-12-24 DE DE19863644514 patent/DE3644514A1/en active Granted
-
1987
- 1987-12-23 EP EP87119088A patent/EP0272696A3/en not_active Withdrawn
- 1987-12-24 CA CA000555415A patent/CA1276668C/en not_active Expired - Lifetime
- 1987-12-24 US US07/137,748 patent/US4862132A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| DE3644514C2 (en) | 1988-12-01 |
| EP0272696A2 (en) | 1988-06-29 |
| US4862132A (en) | 1989-08-29 |
| DE3644514A1 (en) | 1988-07-07 |
| EP0272696A3 (en) | 1989-12-06 |
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Legal Events
| Date | Code | Title | Description |
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| MKLA | Lapsed |