US3450382A - Actuator apparatus - Google Patents

Description

June 17, 1969 T. A. cALlM ACTUATOR APPARATUS Sheet Filed Jan. 26, 1967 94 FIG-2 M/VE/VTDR THOMAS A. CALIM Arron/v57 44 FIG-8 Sheet Filed Jan. 26, 1967 INVENTOR THOMAS A. CALIM ATTORNEY United States Patent 3,450,382 ACTUATOR APPARATUS Thomas A. Calim, Shelby County, Ohio, assignor to Master Swaging & Mfg. Company, Jackson Center, Ohio, a partnership Filed Jan. 26, 1967, Ser. No. 612,011 Int. Cl. F16k 31/163, /04, 31/524 U.S. Cl. 251-58 Claims ABSTRACT OF THE DISCLOSURE This invention relates to actuator apparatus. The invention relates more particularly to actuator apparatus which is linearly operable. The invention relates still more particularly to linearly operable actuator apparatus which is particularly adapted for operation of a rotary member.

Background of the invention A linearly operable actuator or motor member is ordinarily a less complex, smaller, more eflicient, and less costly device than a rotary actuator or rotary motor member. Therefore, it is desirable to employ the use of linearly operable actuator apparatus for operation of a rotatably movable member, as well as for operation of a linearly movable member.

Summary of the invention Brief description of the drawing FIGURE 1 is a perspective view of actuator apparatus of this invention. The actuator apparatus is shown as being operably connected to rotary valve mechanism.

. FIGURE 2 is an enlarged longitudinal sectional view, with parts shown in elevation, of the structure of FIG- URE 1 with the actuator apparatus in the de-actuated position thereof.

FIGURE 3 is a longitudinal sectional view, partly in elevation, and similar to FIGURE 2 but showing the actuator apparatus in an actuated position thereof. The

valve mechanism is thus shown in a difl erent operating position from that illustrated in FIGURE 2.

FIGURE 4 is a sectional view taken substantially on line 44 of FIGURE 2.

FIGURE 5 is a sectional View taken substantially on line 55 of FIGURE 2.

FIGURE 6 is a sectional view taken substantially on line 6-6 of FIGURE 2.

FIGURE 7 is a sectional view taken substantially on line 77 of FIGURE 3.

FIGURE 8 is a sectional view taken substantially on line 8-8 of FIGURE 3.

FIGURE 9 is an exploded perspective view showing the various parts of the actuator apparatus of this invention and the valve mechanism operable thereby.

Description of the preferred embodiment invention. The housing 10 includes a lower portion 12 and an upper portion 14.'It is to be understood, however, that the terms upper and lower are for reference only, in that the apparatus may be positioned with any portion thereof above or below any other portion thereof.

The lower portion 12 of the housing 10 has a cavity or chamber 16; the upper portion 14 of the housing 10 has a cavity or chamber 18.

A piston or motor member 20, which may be formed of any suitable material, is herein shown as being formed of a suitable plastics material or the like. The piston or motor member 20 is disposed within the cavity 16 adjacent the lower end thereof. A cap 22 is threadedly connected to exterior threads 24 on the lower portion 12 of the housing 10 for closing thereof.

An annular washer 26 of plastics material or of other suitablematerial is disposed between the bottom end of the lower portion 12 of the housing 10 and the cap 22 to provide a fluid seal therebetween. As shown in FIG- URES 2, 3, and 9, a sealing ring 28 is disposed within an annular groove 30 in the outer surface of the piston 20 to provide a fluid seal between the piston 20 and the inner wall of the lower portion 12 of the housing 10-.

The cap 22 has a centrally disposed passage 32 therein for transmission of fluid therethrough to the lower surface of the piston 20. The passage 32 communicates with a passage 34 in an adapter 36. A tubular conduit 40, shown in FIGURES 1, 2, and 3, is attached to the adapter 36 and leads to a suitable source of supply of fluid.

A piston rod or stem 42 has its lower end disposed within a recess 44 in the upper surface of the piston 20. The piston rod or stem 42 is connected to the piston 20 for axial or linear movement therewith but is rotatable with respect to the piston 20. The lower end of the rod or stem 42 has an annular groove 46. The piston 20-is provided with aligned transverse passages 50 which communicate with the recess 44. Each of a pair of pins 48 has a mid-portion thereof extending through the recess 44 of the piston 20 and loosely disposed in the annular groove 46 of the stem 42. Each of the pins 48 has the end portions thereof within one of the pair of aligned passages 50. Thus, the rod or stem 42 is rotatably attached to the piston 20, but the rod or stem 42 is axially movable with axial movement of the piston 20.

Thus, when the piston 20 moves upwardly from the position of FIGURE 2, the stem 42 is forced upwardly therewith. When the stem 42 is moved downwardly, the piston 20 is forced downwardly therewith.

The piston 20 and the stem 42 are both constantly urged to the position thereof shown in FIGURE 2 by a coil spring 60. The spring 60, which exerts both a compressional force and a torsional force upon the stem 42, encompasses a portion of the stem 42. The lower end portion of the spring 60 is attached by means of a screw 62 to the stem 42 at a position adjacent the annular groove 46. The screw 62 is disposed within a threaded opening or aperture 64 shown in FIGURE 9.

The upper end portion of the spring '60 base. projection 66, which is disposed within one of three spaced-apart sockets or openings 68, 70, and 72 in a shoulder 74 of the housing 10, shown in FIGURES 7 and 9.

When the projection 66 of the spring 60 is disposed in the opening 68, the spring 60 creates a minimum amount of torsional force on the stem 42. Maximum torsional force of the spring 60 on the stem member 42 is created when the projection 66 of .the spring 60 is disposed in the opening 72. Thus, the torsional force of the spring 60 may be adjusted.

As shown in FIGURES 2 and 3, a portion of the stem 42 extends into the cavity 18. A guide 76, which is preferably formed of anti-friction plastics material, encompasses the stem 42 adjacent the shoulder 74. The guide 76 3 has a notch 78, shown in FIGURE 9, formed therein adjacent the periphery thereof to accommodate the projection 66 of the spring 60. The guide 76 is urged toward the shoulder 74 by the spring 60.

The upper portion 14 of the housing has a pair of diametrically disposed arcuate cam slots 82 formed therein. One of the cam slots 82 is shown in FIGURES 1, 2, 3, and 9. A pin or cam follower 84, which extends diametrically through a passage 86 in the stem 42, has the ends thereof disposed in the cam slots 82. The pin 84 has a snug fit within the stem 42 for retention thereby. The cam slots 82 are created in such curvature and length that the stem 42 has the desired amount of rotative movement when the pin 84 is moved from the bottom of the cam slots 82 to the top of the cam slots 82 by axial movement of the stem 42. While each of the cam slots 82 is shown extending for an arcuate length and curvature of substantially ninety degrees in the housing 10, this arcuate length and curvature of the cam slots 82 may be shorter or greater, depending upon the amount of rotative movement desired for the stem 42.

As shown in FIGURES 2 and 3, a valve housing 94 is attached by means of an adapter 96 to the housing 10 at the upper end thereof. The housing 94 has a flow passage 97 therethrough. A valve 90 within the passage 97 is rotatable to control flow of fluid through the passage 97.

A valve stem 98 is attached to the valve 90 and rotatably extends through the adapter 96 into the cavity 18 of the housing 10.

The valve stem 98 is connected to the piston rod 42 through a pin 100. The pin 100 is snugly disposed within the valve stem 98 and extends therethrough. The pin 100 is positioned within a pair of diametrically disposed axially extending slots 102 in the upper end of the piston rod or stem 42. The rod or stem 42 is thus axially movable with respect to the pin 100 as the end portions of the pin 100 are disposed within the slots 102. The length of the slots 102 is such that the stem 42 can axially move from the position thereof shown in FIGURE 2 to the position thereof shown in FIGURE 3, without causing engagement of the pin 100 with the lower end of the slots 102. Thus, while the rod or stem 42 rotates and moves axially, the valve stem 98 is rotatively moved; thus the valve 90 is rotatively moved.

In order to readily position the pin 100 in the slots 102 the upper portion 14 of the housing 10 is provided with an access opening 104.

In the position thereof shown in FIGURE-2, the valve 90 is closed and prevents flow of fluid through the passage 97 ofthe valve housing 94. When it is desired to operate the valve 90, fluid is supplied to the lower surface of the piston 20 through the conduit 40 and through the passages 32 and 34. Thus, the piston 20 is moved axially or linearly upwardly within the lower cavity 16 of the housing 10. Axial movement of the piston 20 causes axial movement of the stem 42 which is connected thereto. Thus, such movement of the piston 20 and the stem 42 is against the compressional forces of the spring 60.

As the stem 42 moves upwardly, the ends of the pin or cam follower 84 move upwardly within the cam slots 82. Thus, rotative movement of the stem 42 occurs as the stem 42 moves axially. Such rotative movement of the stem 42 is against the torsional forces of the spring 60.

Because of the rotatable connection between the stem 42 and the piston 20, the piston 20 does not rotate with the stem 42. Thus, frictional forces upon the sealing ring 28 are maintained at a minimum.

The amount of upward movement of the piston 20 is determined by the total fluid pressure applied to the lower surface thereof. The total fluid pressure applied to the lower surface of the piston 20 is determined by the per unit pressure of the fluid which enters the lower end of the cavity 16 through the passages 32 and 34. Suflicient fluid pressure may be applied to the lower surface of the piston 20 to move the piston 20 and the stem 42 upwardly until the cam follower 84, carried by the stem 42, reaches the upper end of the cam slots 82. When this occurs, the stem 42 and the piston 20 are in the position shown in FIG- URE 3. Thus, it is to be observed that the piston rod or stem 42 rotates through substantially ninety degrees as the stem 42 moves upwardly from the position thereof shown in FIGURE 2 to the position thereof shown in FIGURE 3. This same amount of rotative movement is transmitted to the Valve stem 98. Thus, the valve is rotated through ninety degrees to the full open position thereof in the passage 97 in the housing 94.

However, the per unit fluid pressure of fluid introduced into the lower end of the cavity 16 may be limited so that the total fluid pressure applied to the lower surface of the piston 20 is not sufficient to move the stem 42 upwardly until the cam follower 84 reaches the upper end of the cam slots 82. When the per unit fluid pressure is so limited, the total fluid pressure applied to the lower surface of the piston 20 forces the piston 20 and the stem 42 upwardly until the total pressure applied to the lower surface of the piston 20, tending to move the piston 20 upwardly, equals the force of the spring 60 which urges the stem 42 and the piston 20 downwardly. Thus, the stem 42 is rotated through an angle less than ninety degrees, and the valve 90 is rotated through an angle of less than ninety degrees. Therefore, the rotative position of the valve 90 is between the closed position thereof shown in FIGURE 2 and the maximum open position thereof shown in FIGURE 3. Thus, the flow of fluid through the passage 97 is less than maximum flow.

The rotative position of the valve 90 or the extent to which the valve 90 is open is therefore dependent upon the per unit fluid pressure which is introduced into the lower end of the cavity 16 through the passages 32 and 34. The fluid flow through the conduit 40 may be controlled by a suitable fluid pressure regulator, not shown, which is adjustable to obtain the desired per unit fluid pressure in accordance with the desired opening of the valve 90. Thus, flow of fluid through the valve 90 is metered as desired.

The valve 90 remains in the desired actuated position thereof so long as suflicient fluid pressure is applied to the lower surface of the piston 20 to maintain the piston 20 at the position thereof which is necessary for the desired opening of the valve 90. When fluid pressure is removed from the lower surface of the piston 20, the spring 60 automatically returns the stem 42 and the piston 20 to the de-euergized position thereof shown in FIG- URE 2. The cam slots 82 in cooperation with the cam follower pin '84, which is carried by the stem 42, cause the stem 42 to rotatively move as downward movement of the stem 42 occurs. As the spring 60 forces the stem 42 downwardly, the spring 60 exerts a torsional force to aid in rotatively moving the stem 42 as the stem 42 moves downwardly.

Operation of the spring 60 assures positive rapid rotative movement of the stem 42 as well as axial movement thereof. The valve stem 98 is rotatively moved with rotative movement of the piston rod or stem 42. Thus, the valve 90 is rotatively returned to the closed position thereof shown in FIGURE 2.

While the valve 90 has been shown as being moved from its closed position to an open position through upward axial and rotative movement of the stem 42, it should be understood that the valve 90 may be moved from an open position to its closed position by the same operation of the piston 20 and the stem 42. Such reverse operation may be accomplished by positioning the pin 100 at ninety degrees with respect to its present position on the valve stem 98.

As previously mentioned, the degree or amount of maximum rotative movement of the stem 42 is determined by the curvature and length of the cam slots 82 in the housing 10. Thus, if less than ninety degrees of maximum rotation of the stem 42 is required or desired, the cam slots 82 are formed in a shorter arcuate length for a lesser amount of rotative movement of the stem 42. Similarly, if greater than ninety degrees of maximum rotation of the stem 42 is required, the cam slots 82 are formed in a greater arcuate length for a greater amount of rotative movement of the stem 42.

Although the actuator ,of this invention has been described with respect to rotative operation of a valve,

it is to be understood that the actuator apparatus of this invention may be utilized with any other suitable device for rotative operation thereof. While the linear or axial movement of the piston 20 has been described as being produced by fluid pressure, it is to be understood that any other type of energy may be employed for axial movement of the piston or motor member 20.

Thus, it is to be understood that the reciprocally operable actuator apparatus of this invention requires the introduction of energy thereinto for operation in only one direction thereof. Furthermore, in this invention the force which returns the actuator mechanism to its original or starting position is adjustable in magnitude. Also, the apparatus of this invention requires no complex linkage connection between the actuator apparatus and a load member to be rotated. A still further advantage of this invention is that fluid sealing problems in regard thereto are a minimum.

The invention having thus been described, the following is claimed:

1. Actuator apparatus for translating linear motion to rotary motion comprising:

a housing provided with a cavity therein,

an actuator unit within the cavity, the actuator unit including a piston and a piston rod, means rotatably connecting the piston to the piston rod, the actuator unit being linearly movable,

the housing having means for introducing fluid thereinto for applying fluid pressure to the piston for linear movement of the actuator unit,

resilient means joined to the actuator unit and to the housing, the resilient means urging the actuator unit in one direction of linear movement, the resilient means including torsion means which urges rotative movement of the piston rod as well as linear movement thereof,

cam means carried by the piston rod and the housing for causing rotative movement of the piston rod with linear movement thereof.

2. The apparatus of claim 1 in which the resilient means comprises a helical spring which encompasses the piston rod and which has an end portion attached to the piston rod and an opposite end portion fixed with respect to the housing.

3. The apparatus of claim 1 in which the piston has a recess, the piston rod having a first end portion, the first end portion being within the recess, the first end portion of the piston rod being provided with an annular peripheral groove, there being at least one pin member extending through a part of the annular peripheral groove of the piston rod and having a portion attached to the piston so that the piston is rotatable with respect to the piston rod while being connected thereto for axial movement therewith.

4. The apparatus of claim 1 in which the housing is provided with an arcuate cam surface and in which a pin extends transversely through the piston rod and has an end thereof movable along the arcuate cam surface of the housing for rotative movement of the piston rod with axial movement thereof.

5. The apparatus of claim 3 in which the piston rod has a second end portion,

means for operably connecting the second end portion of the piston rod to a rotatable load member for rotative movement of the load member with axial and rotative movement of the piston rod.

6. The apparatus of claim 5 in which the second end portion of the piston rod has a recess therein which is adapted to receive a rotatable load member, said second end portion of the piston rod also being provided with a pair of axially extending slots, the load member having a part within the recess of the piston rod, a pin extending through the load member and having parts thereof within the slots of the piston rod so that the load member is rotative with rotative and axial movement of the piston rod, there being relative axial movement between the load member and the piston rod during rotative movement of the piston rod and the load member.

7. In combination with a valve device provided with a housing having a passage therethrough, there being a rotary valve within the passage for controlling flow of fluid therethrough, there being a valve stem attached to the rotary valve and extending from the housing, actuator apparatus comprising:

a housing,

means attaching the housing of the actuator apparatus to the housing of the valve device, the housing of the actuator apparatus having a cavity therein,

motor means within the cavity and movable toward and away from the housing of the valve device,

a motor stem connected to the motor means for rotative movement with respect thereto, the motor stem being axially movable with linear movement of the motor means toward and away from the housing of the valve device,

cam means carried by the housing,

cam follower means carried by the motor stem and engageable with the cam means so that there is rotative movement of the motor stem with axial movement thereof,

means connecting the motor stem to the valve stem for rotative movement of the valve stem with axial and rotative movement of the motor stem,

resilient means connected to the motor stem and in engagement with the housing and urging axial movement of the motor stem in a direction away from the housing of the valve device, the resilient means comprising a helical spring which urges rotary movement as well as axial movement of the motor stem.

'8. The combination of claim 7 in which the housing of the actuator apparatus has a plurality of sockets therein and the helical spring has an end portion disposed within one of the sockets, the sockets being spaced-apart so that as the end portion of the helical spring is positioned in one socket the torsional forces thereof are different from the torsional forces obtained when the end portion of the spring is positioned in another of the sockets.

9. The combination of claim 7 in which the motor stem has an elongate axially extending slot therein, a pin carried by the valve stem and having a portion extending into the elongate slot of the motor stem for rotative movement of the valve stem with axial and rotative movement of the motor stem.

10. In combination, a rotatable load member and actuator means to rotate said load member,

said actuator means including a housing having an elongate cavity therein,

a motor member movably disposed within said cavity,

a cylindrical member mo-vably disposed within said cavity,

means connecting said cylindrical member to said motor member for axial movement of the cylindrical member with movement of the motor member,

resilient means constantly urging said cylindrical member toward one end of the elongate cavity, the resilient means also constantly and directly urging rot-ation of the cylindrical member,

the motor member being operably movable toward the References Cited other end of the elongate cavity, UNITED STATES PATENTS said housing and said cylindrical member having coop- 840,867 1/1907 Rice X crating cam means causing said cylindrical member 52 297 3 1925 Jones 137 505,2 to rotatively move with axial movement thereof, 5 3,071,015 1/1963 Donguy 92-31 X means connecting the cylindrical member to the load 3,319,925 5/1967 Koichi Kojima et al. 74--99 X member for rotative movement of the load membet with axial and rotative movement of the cylindri- CARY NELSOI? Prlmary xammen cal member so that only the rotative movement of 10 Ass'smm Exammer' the cylindrical member is transmitted to the load U.S. CI.X.R. member. 9231; 251-256

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