US3882296A

US3882296A - Leaf spring switching means

Info

Publication number: US3882296A
Application number: US413078A
Authority: US
Inventors: Peter Keith Townsend
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1973-11-05
Filing date: 1973-11-05
Publication date: 1975-05-06
Anticipated expiration: 1992-05-06
Also published as: AU7442774A; CH576698A5; JPS5074781A; ATA861374A; NL7413595A; ES431543A1; AT336692B; AR200979A1; SE7413881L; DE2449950A1; CA1017779A; IT1030721B; SE395074B; HK18579A; FR2250191A1; GB1480262A; BR7409027A; BE821570A

Abstract

A switch having a plurality of leaf spring type contacts held in a stacked, but spaced-apart manner, with each spring having one end thereof secured in a common plastic base. The base has slots formed therein to receive the leaf springs and also has holes therein, at right angles to the plane of the slots, to receive lead-in wires. To assemble the switch, the lead-in wires are simply cut off at their ends and inserted into their respective holes. The leaf springs are then inserted in their respective slots. Each leaf spring has a slotted appendage thereon which slips over a particular and unique lead-in wire within the housing, cuts away the insulation thereon, and makes contact with the metal conductor therein. The assembled switch requires no discrete terminals secured to the ends of the lead-in wires nor any screws, bolts or other fastening means to hold the leaf springs in the common base. The plastic housing holds the leaf springs therein by force-fit means.

Description

United States Patent [1 1 Townsend LEAF SPRING SWITCHING MEANS [75] Inventor: Peter Keith Townsend, Cumberland,

[73] Assignee: AMP Incorporated, Harrisburg, Pa. [22] Filed: Nov. 5, 1973 [21] Appl. No.: 413,078

Primary Examiner-Harold Broome Attorney, Agent, or Firm-AMP incorporated May 6,1975

[ 57] ABSTRACT A switch having a plurality of leaf spring type contacts held in a stacked, but spaced-apart manner, with each spring having one end thereof secured in a common plastic base. The base has slots formed therein to receive the leaf springs and also has holes therein, at right angles to the plane of the slots, to receive lead-in wires. To assemble the switch, the lead-in wires are simply cut off at their ends and inserted into their respective holes. The leaf springs are then inserted in their respective slots. Each leaf spring has a slotted appendage thereon which slips over a particular and unique lead-in wire within the housing, cuts away the insulation thereon, and makes contact with the metal conductor therein. The assembled switch requires no discrete terminals secured to the ends of the lead-in wires nor any screws, bolts or other fastening means to hold the leaf springs in the common base. The plastic housing holds the leaf springs therein by force-fit means.

16 Claims, 29 Drawing Figures PATENTEDHAY 6 I975 SHEET UlUF 5 PATENTEDHAY 51975 sum near 5 PATENIEU w 'sizs SHEET 03 UP 5 SECTION B-E;

PATENTEDHAY 61975 3.882.296

' SHEET w ssJ 7225/ 72E]; /215 7171-, L? 71-22737? 71E H 71-2: M;

Th Z5 [5 71.7 15 71-, .15; E, 12 T5125 LEAF SPRING SWITCHING MEANS BACKGROUND OF THE INVENTION This invention relates generally to switches, and more particularly to switches of the type known as line switches which are employed extensively in the telephone industry, but which have many other applications, as well.

Essentially, a line link switch is a series of leaf spring type contacts which are stacked, one over the other, and secured in such stacked position by a plurality of insulated spacers positioned at one end of the leaf springs and in-between adjacent leaf springs. A pair of screws extend through the stack of spacers and leaf springs to hold them in position. The free end of each of the leaf springs has at least one contact formed thereon and in bifurcated in nature so that what is known as a card can be inserted into the slots formed by such bifurcations. As the card is moved to and fro, in a line perpendicular to the plane of the leaf springs, electrical contacts between various adjacent ones of the spring leaf are made or broken to perform desired electrical switching functions.

At least one of these leaf springs is employed in each telephone hand set. Furthermore, large quantities of these type switches are employed in other switching equipment in the telephone industry. Also extensive use of this type switch is made in many other kinds of electrical equipment, such as for example, pin ball machines, appliances and industrial controls.

In the presently employed line link switch, bolts or screws extend through the alternate stack of leaf springs and insulating spacers or separators positioned therebetween, to hold the entire assembly of leaf springs together in a desired relationship. An external electrical connection is made to individual ones of the leaf springs by means of a spade-like termination secured to lead-in wires. These spade-like terminations are positioned between the leaf spring to which it is connected and an adjacent insulating spacer. The screws that hold the spacer or separator and leaf springs together also function to hold the spade terminal in its place and in electrical contact with one of the leaf springs.

The cost of the presently employed line link switch is fairly high for several reasons. More specifically, each of the lead-in wires has a spade-like termination thereon, as mentioned above, in order to connect with one of the spring leaf contacts. Furthermore, a plurality of insulating spacers must be manufactured and then individually positioned in-between the various spring leaves. Each of the spring leaves and insulating separators must have a pair of holes drilled therein to receive the two screws which hold the entire assembly together. It is also apparent that in the manufacturing thereof, means must be provided to stack the leaf springs and the separators together in the proper order and with the holes therein aligned so that the supporting screws can be inserted.

BRIEF STATEMENT OF THE INVENTION It is a primary object of the present invention to provide a line link switch of at least equal quality and reliability to the presently used line link switch, but having a fraction of the manufacturing cost thereof.

It is a second aim of the invention to provide a line link switch which does not require separate insulating spacers.

It is a third aim of the invention to provide a line link switch which does not require separate insulating spacers nor does it require spade or other type discrete terminals connected to the lead-in wires.

It is a fourth purpose of the invention to provide a line link switch which does not require separate insulating spacers, nor discrete terminals for making contact between the lead-in wires and the spring contacts nor does it require any screws or bolts to hold the leaf springs and spacers to together as an assembly.

It is a fifth purpose of the invention to provide a line link switch having a connector housing into which the cut end of the insulated lead-in wires can be inserted and into which each of the leaf springs subsequently can be inserted thereby stripping away the insulation on selected lead-in wires to thereby make a good and permanent electrical connection with said lead-in wires.

It is a sixth purpose of the invention to provide a line link switch comprised only of leaf springs, a plastic housing and a metal bracket, and in which cut ends of lead-in wires are inserted into the plastic base followed by insertion of the leaf springs, each of which functions to strip away the insulation on a given one of the lead-in wires to make electrical connection therewith, and further in which said plastic housing and the leaf springs co-act together so that insertion of the leaf springs into said housing provides the structural strength to support said leaf springs without the aid of any additional support.

It is a further object of the invention to provide a line link switch consisting only of a plastic housing, a plurality of leaf springs, a plurality of lead-in wires and a metal bracket, and in which all electrical connections and all required mechanical support is obtained by simply inserting the leaf springs into slots provided therefore in said plastic housing.

Another aim of the invention is the improvement of line link switches generally.

In accordance with the present invention there is provided a plastic housing having a plurality of slots, usually seven, which are substantially parallel to each other and with the openings thereof all on one major, flat surface of the housing. A plurality of holes, also usually seven, are formed in said housing substantially at right angles to the plane of the slots and with the holes penetrating into the housing to different depths, and more specifically with each hole extending just beyond one of the given slots so that when the leaf-spring is inserted in said one slot said leaf spring will engage only the lead-in wire inserted in said each hole. The seven holes can be arranged into two rows of holes, one on either side of the stack of slots and with the holes aligned at substantially right angles to the major planes of the slots. The holes nearest the slot openings in each row penetrate past only the first slot, the next hole penetrating just past the second hole, etc. With the foregoing arrangement each leaf spring, when inserted in its slot, will engage only one lead in wire.

The engagement between the leaf springs and the lead-in wires is effected by means of an appendage which extends out from the side of each leaf spring and which contains a slot. When said leaf spring is inserted into the housing slot, the slot in the appendage slides over the lead-in wire inserted in the hole associated therewith and strips the insulation from said lead-in wire, thereby making electrical contact between the spring leaf and the lead-in wire.

Spring-like finger elements and embossed areas are formed on each of the leaf springs which function to grip the walls of the slot into which the leaf spring is inserted so as to provide a rigid support in said housing for the spring leaf, and further to prevent unauthorized extraction of a spring leaf from the plastic housing. Each of the seven spring leaves can be inserted separately, or simultaneously by an appropriate tool or antomated equipment. To assemble the switch it is only necessary to insert the lead-in wires into their proper holes in the housing followed by insertion of the leaf springs into their proper slots. A metal bracket is provided to hold the assembled switch onto a suitable chassis which is provided therefor, as for example, in telephone bases.

In accordance with a feature of the invention the slots formed in the appendages on the spring leaves have their edges bent at right angles to the plane of the leaf spring so that the slot formed thereby is largest near the open end thereof and decreases in width towards the top or closed end thereof. Thus, as said slot is pressed down over the lead-in wire there are no sharp edges which will cut through the insulation and into the copper conductor contained therein to damage said conductor. The action of said slot with its bent-over edges is, in effect, to wear away the insulation on the wire as the slot is pressed down and over said wire, thereby providinga safe means of removing the insulation from the lead-in wire but yet establishing good electrical contact with the metal conductor as the slot finally seats upon said conductor.

BRIEF DESCRIPTION OF THE DRAWINGS The above-mentioned and other objects and features of the invention will be more clearly understood from the following detailed description thereof when read in conjunction with the drawings in which:

FIGS. 1 through 4 show four perspective views of the switch in various stages of assembly;

FIG. 5 shows a broken away perspective view of one leaf spring inserted into the plastic housing and the physical connection it makes with a lead-in conductor inserted in the hole therefore in said plastic housing;

FIG. 5a is a perspective view of one leaf spring;

' FIG. 5b is a blown-up view of a portion of the structure of FIG. 5a;

FIG. 6 is a top plan view of the plastic housing showing the openings of the slots provided for the spring leaves;

FIG. 7 is a sectioned view taken along the plane CC of FIG. 6;

FIG. 8 is a sectioned view taken along the plane BB of FIG. 6 and shows the intersection of three of the slots and the holes for the lead-in wires on one side of the stack of slots;

FIG. 9 is another sectional view of FIG. 6 taken along the plane A-A and shows the intersection of four of the slots for the spring leaves and the holes provided for the lead-in wires;

FIG. 10 is an end view of the structure of FIG. 6 and shows theentrances of the seven holes provided for the seven lead-in wires;

4 FIGS. 11, 110,12, 12a, 13,13a,14,l4a,l5,15a,16,

16a, 17, and 17a show plan views and side views of each of the seven spring leaf elements;

FIGS. 18 and 19 show the switch in its two operating positions; and

FIG. 20 shows a perspective view of the card element 100 employed in the switch.

DETAILED DESCRIPTION OF THE INVENTION The invention will be most readily understood from a consideration of FIGS. 1 through 4 in conjunction with FIGS. 5 through 8. More specifically FIGS. 1 through 4 showthe line switch in various stages of assembly. The invention will be described by discussing the insertion of one of the lead-in wires 34 into the housing 20 followed by the insertion of the leaf spring 21 into the housing 20, as shown in FIG. 1. With the aid of FIGS. 6 through 9 it will be shown how the leaf spring 21 interacts with the lead-in wire 34 within the housing to make an electrical connection with said lead-in wire 34, and also to provide a good mechanical support in the housing for leaf spring 21.

Next, the insertion of a second wire 30 and the insertion of a second leaf spring 22 into the housing 20 will be discussed, as shown in FIGS. 1 and 2. Again the coaction between the second leaf spring 22 and the wire 30 will be explained with the aid of FIGS. 6 through 9.

From the discussion of the assembly of the two

wires

34 and 30 and the

leaf springs

21 and 22 it will be apparent how the remaining five lead-in

wires

35, 36, 31, 32 and 33, and the remaining five

leaf springs

23, 24, 25, 26 and 27 are inserted into the housing 20 to complete the assembly of the switch.

The details of the construction of the seven different leaf springs and the means by which they are activated, one with respect to another, will then be discussed in connection with FIGS. 18 and 19.

The different configurations employed in each of the seven leaf springs are shown in FIGS. 11 through 17 and will be discussed with respect to such Figures.

Referring now specifically to FIG. 1 a lead-in wire 34 is shown as being inserted in aperture 34a and the leaf spring 21 as being inserted in slot 21a. In their inserted positions the insulation on the wire 34a is worn through by a slot-containing projection on leaf spring 21. The intersection of the slot 21a with the aperture 34a can be seen in FIG. 8, which is a sectional view taken along the plane BB of FIG. 6.

The condition that exists when leaf spring 21 is inserted in slot 21a and wire 34 is inserted in hole 34a is shown in the broken-away perspective view of FIG. 5. The actual connection between leaf spring 21 and wire 34 occurs as a result of a tab or projection 71 which is attached to leaf spring 21. Such tab 71 has a slot formed therein, with the opening of the slot 70 being at the bottom of tab 71. Thus, when leaf spring 21 is inserted downwardly in slot 21a in the direction of arrow 72, the slot 70 in tab 71 will pass over wire 34 and, in effect, squeeze away the insulation on said wire 34 and make electrical connection with the metal conductor 73 contained therein.

The leaf spring 21 is shown in more detail in FIG. 5 and in the perspective view in FIG. 5a wherein the details of the slot 70 and the tab 71 can be seen more clearly. More specifically in FIG. 5a it can be seen that slot 70 has the

sides

73 and 74 thereof bent over into triangularly shaped sections at to the plane of the tab 71.- Further, slot- 70 is wider at the bottom than it is at the top portion 75 thereof. Thus when tab 71 is moved down upon conductor 34 the inner surfaces of the

triangular elements

73 and 74 will function to literally wear away the insulation on the lead wire 34 and by the time the wire 34 reaches the top of the slot 75 the insulation will have been worn away and electrical contact will be made between the sides of the slot and the wire 34.

It is to be noted that the wearing away of the insulation on wire 34 rather than leaving sharp edges on the inside of slot 70 to cut through the insulation on wire 34 is desirable since the wire 78 is a fine wire of approximately wire size 27, which could be damaged by a sharp edge on the inner surfaces of slot 70.

Due to the presence of the

triangular elements

73 and 74 at the edges of slot 70 it is necessary to widen the slot 20 in the housing 20 (see FIG. 6) to permit entry of said

tabs

73 and 74 therein. More specifically, the widened portion 80 of slot 20 of FIG. 6 is positioned to permit entry therein of tab 70 of FIG. 5a, and the

elements

73 and 74 of tab 71 of FIG. 5b.

The

tabs

76 and 77, formed in the leaf spring 21, abut against the top surface 79 of base 20, thereby determining the depth of penetration of the leaf spring 21 into the housing 20.

Returning again to FIG. 1, the leaf spring element 22 is the next element to be inserted in the housing 20. Specifically, the leaf spring element 22 is inserted in slot 22a and makes connection with the wire 30, also inserted in the housing 20. The connection between lead-in wire 30 and leaf spring 22 is effected by means of the slot 88 in the tab 37 of leaf spring 22, as shown in FIG. 13. It is to be noted that lead-in wire 30 is inserted in a hole in the housing 20 on the opposite side thereof from hole 34.

Reference is made to FIG. 9 which shows a sectional view of the structure of FIG. 6 along the plane AA. It can be seen from FIG. 9 that four of the seven lead-in wires are inserted in the four

apertures

30a, 31a, 32a and 33a, which are intersected respectively by the

slots

22a, 24a, 26a and 27a respectively, as shown in FIGS. 8 and 9. The particular leaf spring which fits into slot 22a is shown in detail in FIG. 12. The tab 37 on leaf spring 22 of FIG. 12 has a slot 88 therein which is formed in the same manner as the slot 70 of FIG. 5b. The sides of slot 88 are formed into triangular elements bent therefrom at right angles to the plane of tab 37, also in the same manner as the

triangular elements

73 and 74 of slot 70 in FIG. 5b are formed.

When spring leaf 22 is inserted in slot 220 of FIG. 1 the slot 88 in tab 37 thereof will strip away the insulation on lead-in wire 30 and make electrical contact therewith. Such interaction between the spring leaf 22 and the lead-in wire 30 can be seen from the sectional plan view of FIG. 9 wherein it is shown that slot 22a, into which spring leaf 22 is inserted, intercepts aperture 30a, into which lead-in wire 30 is inserted.

As in the case described above hereinbefore in which the first spring leaf 21 was inserted in slot 21a to intercept lead-in wire 34. The aperture 30a extends beyond the slot 22a in FIG. 9. The lead-in wire 30 will accordingly also extend beyond said slot 22a so as to bridge said slot and provide structural strength. Thus when tab 37 of spring leaf 22 is forced down over the wire 30, that portion of wire which will be stripped of insulation will be supported on either side thereof to facilitate such stripping of the insulation therefrom.

In FIG. 2 the spring leaf 22 is shown as inserted in the base 20 along with leaf spring 21. In addition, the

leadin wires

30, 31, 34 and 35 are also shown as being inserted. The leaf spring 24 is shown along side the base 20 in a non-inserted position. When inserted into base 20 the spring leaf 24 will intercept the lead-in wire 31.

In FIG. 3 five of the seven

leaf springs

21, 22, 23, 24 and 25 are shown inserted in base 20. Six of the lead-in

wires

30, 31, 32, 33, 34, 35 and 36 are also shown as being inserted in base 20. The completed assembly, including the inserted seven leaf springs 21 through 27 and the inserted seven lead-in wires 30 through 36, is

shown in FIG. 4. Also shown in FIG. 4 is a bracket. In the completed assembly the following connections between the various leaf springs and the lead-in wires are made;

leaf springs

22, 24, 26 and 27 are connected, respectively, to lead-in

wires

30, 31, 32 and 33. Spring leaves 21, 23 and 25 are connected, respectively, to lead-in

wires

34, 35 and 36. I

Each of the seven individual leaf springs 21 through 27 have different configurations and front plan views thereof are individually shown in FIGS. 11 through 17 respectively. FIGS. 11a through 17a show a side view of leaf springs 21 through 27, respectively. From FIGS. 12 through 17 it can be seen that each of the leaf springs 21 through 27 has a different stamped out configuration at the bifurcated end thereof. Such differences in the stamped out portion at the bifurcated ends of the leaf springs is needed in order to accommodate a card element which fits into the slots formed by such bifurcations and moves certain of the leaf springs back and forth to make and break contacts with other leaf springs. Reference is made to FIGS. 18 and 19 which show the seven leaf springs 21 through 27 mounted in their plastic base 20 which in turn is mounted on a metal bracket 106. The card element 100 slides down into the slot at the bifurcated end of the leaf springs 21 through 27 and has two positions, one as shown in FIG. 18 and the other as shown in FIG. 19, which shows card element 100 moved to the right in the direction of the arrow 108. Furthermore, card 100 has

elements

101, 102 and 103 formed thereon which are wider than the main body of card 100 and function to grip the bifurcated elements of

leaf springs

26, 24 and 21, respectively. Thus, when card 100 is moved to its rightmost position as shown in FIG. 19, the

elements

101, 102 and 103 function to pull back the

leaf springs

26, 24 and 21.

When leaf springs 26 and 24 are pulled back as I shown in FIG. 19, the contacts 111 and 117 thereof break with contacts and 116 of

leaf springs

27 and 22 respectively, and the contact 114 of leaf spring 24 mates with contact of leaf spring 23. Also, contact 112 of leaf spring 26 mates with the contact 113 of leaf spring 25.

The circuit connections made or disconnected by the foregoing breaking and making of the contacts of the leaf springs 21 through 27 is not important for the purposes of this invention. The important consideration is that the afore-mentioned breaking and making of contacts is effected when the card 100 is moved from its leftmost position of FIG. 18 to its rightmost position as shown in FIG. 19 by virtue of

theprojections

101, 102 and 103 on the card 100.

It is also to be noted that the making and breaking of the contacts with the present invention, as shown in FIGS. 18 and 19, exactly duplicates the making and breaking of contacts in the prior art conventional line link switch described in the introduction to this specification. Furthermore, the configuration of the leaf springs and also of the card l-can be exactly the same as the prior art. The important and inventive difference is in the manner in which the leaf springs are connected into the base 20 and the manner in which the leaf springs make electrical connection with the lead-in wires 30 through 36 of FIG. 4.

In FIG. 20 there is shown a top view of the card 100.

It can be seen from FIG. 20 that the projections 101,

I02 and 103 are sufficiently wide to grip the two legs formed by bifurcating the ends of the

leaf springs

26, 24 and 21 of FIGS. 18 and 19.

The stamped out portion of

leaf springs

27, 25, 23 and 22 between the bifurcated legs thereof is sufficiently wide so that the card 100 will pass therethrough from its leftmost position in FIG. 18 to its rightmost position in FIG. 19, without engaging the bifurcated legs of said

leaf springs

27, 25, 23 and 22. The projections 101,102 and 103 do not at any time come into contact with the

leaf springs

27, 25, 23 and 22. Only the

leaf springs

26, 24 and 21 are activated by the

projections

101, 102 and 103. Of these three

leaf springs

26, 24 and 21 only the

leaf springs

26 and 24 are activated to engage

adjacent leaf springs

25 and 23 respectively, as shown in FIGS. 18 and 19.

It is to be understood that the form of the invention shown herein is but a preferred embodiment thereof and that various changes in specific design of the leaf springs of the housing base can be made without departing from the spirit or scope thereof. For example, while the described embodiment of the invention is a line link switch used in the telephone industry the principles of the invention are applicable to almost any application involving a plurality of leaf springs held in a common base and activated by a card means.

What is claimed is: I l. A leaf spring type switch comprising: a plurality of leaf spring contacts having a longitudi nal axis; a plurality of lead-in wires; a base of molded, insulative material comprising a plurality of slots formed therein and positioned in a side-by-side relationship with each other in a stacked manner, and with said slots all opening in substantially the same direction from said base; each slot lying in a separate plane with said separate planes positioned to intersect a first given plane at parallel lines of intersection; said base further comprising a plurality of apertures formed therein, each of said apertures being oriented to intersect different ones of said slots;

one of said lead-in wires being inserted in each of said apertures to intersect said different ones of said slots;

one of said leaf spring contacts being retained in each of said slots with its longitudinal axis being substantially perpendicular to said parallel lines of intersection;

at least some of said leaf spring contacts having a 6 notch formed therein, with said notch of each leaf spring contact being positioned to engageably slide over the particular lead-in wire inserted in the aperture which intersects with the slot in which said each leaf spring contact is inserted, to thereby make electrical contact with said particular lead-in wire; and actuating means for connecting and disconnecting slective ones of said leaf spring contacts. 2. A leaf spring type switch in accordance with claim 1 in which:

each of said leaf spring contacts comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring contact in the slot in which it is inserted; and

in which said notched appendage is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

3. A leaf spring type switch in accordance with claim 1 in which each of said leaf spring contacts has its free end bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising: I

card means positioned within said cut-out portions of said leaf springs contacts and constructed to move selected ones of said leaf springs contacts to make and break electrical contact between predetermined ones of said leaf spring contacts. 4. A leaf spring type switch in'accordance with claim 3 in which:

each of said leaf spring contacts comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring contact in the slot in which it is inserted; and in which said notched appendage is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof. 5; A leaf spring type switch comprising: a base of molded, insulative material comprising a plurality of slots formed therein and positioned in a side-by-side relationship with each other in a stacked manner and with said slots all opening in substantially the same direction from said base;

each slot lying in a separate plane parallel with the I planes of the other slots; v

said base further comprising a plurality of apertures, each of said apertures being oriented to intersect different ones of said slots;

a plurality of insulated lead-in wires individually inserted in each of said apertures to intersect said different ones of said slots;

a plurality of leaf springs each inserted in a given one of said slots and each comprising an element thereon constructed to engage the lead-in wire intersecting said given slot to remove the insulation from said intersecting lead-in wire and to make electrical connection therewith; and

actuating means for connecting and disconnecting selective ones of said leaf springs.

6. A leaf spring type switch in accordance with claim 5 in which:

each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said molded base to securely hold said leaf spring in the slot in which it is inserted; and

in which said element is constructed to mechanically grip said intersecting lead-in to prevent unauthorized withdrawal thereof.

7. A leaf spring type switch in accordance with claim 5 in which each of said leaf springs has the free end thereof bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising:

card means positioned within said cut-out portions of said leaf springs and constructed to move selected ones of said leaf springs to make and break electrical contact between predetermined ones of said leaf spring. 8. A leaf spring type switch in accordance with claim 7 in which:

in which said element is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

9. A leaf spring switch comprising:

a base of insulative material and comprising:

a plurality of slots formed therein and positioned side-by-side in a stacked manner in parallel planes;

a plurality of apertures formed therein, each oriented to intersect at least one of said slots;

a plurality of insulated lead-in wires individually inserted in one each of said apertures to thereby intersect at least one of said slots; and

a leaf spring inserted in each of said slots, and comprising an element constructed to engage the intersecting lead-in wire to remove the insulation from said intersecting lead-in wire and to make electrical connection therewith; and

actuating means to connect together selected ones of said leaf springs.

10. A leaf spring type switch in accordance with claim 9 in which:

each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring in the slot in which it is inserted; and

11. A leaf spring type switch in accordance with claim 9 in which each of said leaf springs has the free end thereof bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising:

card means positioned within said cut-out portions of said leaf springs and constructed to move selected ones of said leaf springs to make and break electrical contact between predetermined ones of said leaf spring.

12. A leaf spring type switch in accordance with claim 11 in which:

13. A switch assemblage in accordance with claim 9 in which:

each of said base portions comprises holding elements formed thereon with contact the sides of the slot in said base to securely hold said contact in the slot in which it is inserted; and

14. A switch assemblage in accordance with claim 9 in which each of said contacts has its free end therof bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising:

card means positioned within said cut-out portions of said contacts and constructed to move selected ones of said contacts to make and break electrical contact between predetermined ones of said contacts.

15. A leaf spring type switch assemblage in accordance with claim 14 in which:

16. A switch assemblage comprising:

a plurality of contacts each comprising a flat base portion;

a plurality of lead-in wires;

a base of molded, insulation material having a plurality of parallel slots therein arranged in a stacked manner, and a plurality of apertures therein each oriented to intersect at least one of said slots;

a lead-in wire inserted in each aperture to intersect a slot;

a base portion of a contact retained in each slot;

said slots and apertures being arranged and constructed to enable the base portion of each contact to intersect one lead-in wire to the exclusion of the remaining lead-in wires; and

each base portion comprising an element constructed to engage the intersecting lead-in wire to make electrical contact therewith; and

means for making electrical contact between selected ones of said contacts.

Claims

1. A leaf spring type switch comprising: a plurality of leaf spring contacts having a longitudinal axis; a plurality of lead-in wires; a base of molded, insulative material comprising a plurality of slots formed therein and positioned in a side-by-side relationship with each other in a stacked manner, and with said slots all opening in substantially the same direction from said base; each slot lying in a separate plane with said separate planes positioned to intersect a first given plane at parallel lines of intersection; said base further comprising a plurality of apertures formed therein, each of said apertures being oriented to intersect different ones of said slots; one of said lead-in wires being inserted in each of said apertures to intersect said different ones of said slots; one of said leaf spring contacts being retained in each of said slots with its longitudinal axis being substantially perpendicular to said parallel lines of intersection; at least some of said leaf spring contacts having a notch formed therein, with said notch of each leaf spring contact being positioned to engageably slide over the particular lead-in wire inserted in the aperture which intersects with the slot in which said each leaf spring contact is inserted, to thereby make electrical contact with said particular lead-in wire; and actuating means for connecting and disconnecting slective ones of said leaf spring contacts.

2. A leaf spring type switch in accordance with claim 1 in which: each of said leaf spring contacts comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring contact in the slot in which it is inserted; and in which said notched appendage is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

3. A leaf spring type switch in accordance with claim 1 in which each of said leaf spring contacts has its free end bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising: card means positioned within said cut-out portions of said leaf springs contacts and constructed to move selected ones of said leaf springs contacts to make and break electrical contact between predetermined ones of said leaf spring contacts.

4. A leaf spring type switch in accordance with claim 3 in which: each of said leaf spring contacts comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring contact in the slot in which it is inserted; and in which said notched appendage is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

5. A leaf spring type switch comprising: a base of molded, insulative material comprising a plurality of slots formed therein and positioned in a side-by-side relationship with each other in a stacked manner and with said slots all opening in substantially the same direction from said base; each slot lying in a separate plane parallel with the planes of the other slots; said base further comprising a plurality of apertures, each of said apertures being oriented to intersect different ones of said slots; a plurality of insulated lead-in wires individually inserted in each of said apertures to intersect said different ones of said slots; a plurality of leaf springs each inserted in a given one of said slots and each comprising an element thereon constructed to engage the lead-in wire intersecting said given slot to remove the insulation from said intersecting lead-in wire and to make electrical connectIon therewith; and actuating means for connecting and disconnecting selective ones of said leaf springs.

6. A leaf spring type switch in accordance with claim 5 in which: each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said molded base to securely hold said leaf spring in the slot in which it is inserted; and in which said element is constructed to mechanically grip said intersecting lead-in to prevent unauthorized withdrawal thereof.

7. A leaf spring type switch in accordance with claim 5 in which each of said leaf springs has the free end thereof bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising: card means positioned within said cut-out portions of said leaf springs and constructed to move selected ones of said leaf springs to make and break electrical contact between predetermined ones of said leaf spring.

8. A leaf spring type switch in accordance with claim 7 in which: each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said molded base to securely hold said leaf spring in the slot in which it is inserted; and in which said element is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

9. A leaf spring switch comprising: a base of insulative material and comprising: a plurality of slots formed therein and positioned side-by-side in a stacked manner in parallel planes; a plurality of apertures formed therein, each oriented to intersect at least one of said slots; a plurality of insulated lead-in wires individually inserted in one each of said apertures to thereby intersect at least one of said slots; and a leaf spring inserted in each of said slots, and comprising an element constructed to engage the intersecting lead-in wire to remove the insulation from said intersecting lead-in wire and to make electrical connection therewith; and actuating means to connect together selected ones of said leaf springs.

10. A leaf spring type switch in accordance with claim 9 in which: each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring in the slot in which it is inserted; and in which said element is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

11. A leaf spring type switch in accordance with claim 9 in which each of said leaf springs has the free end thereof bifurcated with a cut-out portion of distinct configuration between the two legs formed by said bifurcation, and further comprising: card means positioned within said cut-out portions of said leaf springs and constructed to move selected ones of said leaf springs to make and break electrical contact between predetermined ones of said leaf spring.

12. A leaf spring type switch in accordance with claim 11 in which: each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring in the slot in which it is inserted; and in which said element is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

13. A switch assemblage in accordance with claim 9 in which: each of said base portions comprises holding elements formed thereon with contact the sides of the slot in said base to securely hold said contact in the slot in which it is inserted; and in which said element is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

14. A switch assemblage in accordance with claim 9 in which each of said contacts has its free end therof bifurcated with a cut-out portion of distinct configuration between the two legs Formed by said bifurcation, and further comprising: card means positioned within said cut-out portions of said contacts and constructed to move selected ones of said contacts to make and break electrical contact between predetermined ones of said contacts.

15. A leaf spring type switch assemblage in accordance with claim 14 in which: each of said leaf springs comprises holding elements formed thereon which contact the sides of the slot in said base to securely hold said leaf spring in the slot in which it is inserted; and in which said element is constructed to mechanically grip said intersecting lead-in wire to prevent unauthorized withdrawal thereof.

16. A switch assemblage comprising: a plurality of contacts each comprising a flat base portion; a plurality of lead-in wires; a base of molded, insulation material having a plurality of parallel slots therein arranged in a stacked manner, and a plurality of apertures therein each oriented to intersect at least one of said slots; a lead-in wire inserted in each aperture to intersect a slot; a base portion of a contact retained in each slot; said slots and apertures being arranged and constructed to enable the base portion of each contact to intersect one lead-in wire to the exclusion of the remaining lead-in wires; and each base portion comprising an element constructed to engage the intersecting lead-in wire to make electrical contact therewith; and means for making electrical contact between selected ones of said contacts.