US3582594A

US3582594A - Actuator useable for electric switches and the like

Info

Publication number: US3582594A
Application number: US776148A
Authority: US
Inventors: Robert H Twyford
Original assignee: MECHANICAL ENTERPRISES Inc
Current assignee: MECHANICAL ENTERPRISES Inc
Priority date: 1968-11-15
Filing date: 1968-11-15
Publication date: 1971-06-01
Anticipated expiration: 1988-06-01

Abstract

An actuator assembly including spring elements unitarily formed of a flexible, resilient, synthetic resin material and driver and driven members which may be integrally formed with said spring elements to provide a new and novel integral actuator assembly capable of formation in a single molding operation and particularly adaptable for use as an electrical switch.

Description

O I United States Patent 1 1 3,582,594

[72] inventor Robert H. Twylord 3,389,902 6/1968 Young 200/67(D)UX Falls Church, Va. 3,3 22,924 5/1967 Sheps l ZOO/157 [21] Appl. No 776,148 3,403,236 9/1968 Zoludow 200/172(X) [22] Filed Nov. 15, 1968 3,403,237 9/1968 Wysong l 200/172(X) [45] Patented June 1,1971 3,472,974 10/1969 McGough 200/159(X) [73] Assignee Mechanical Enterprises Incorporated l 1 PATENTS 1,389,875 1/1965 France 200/172 [54] ACTUATOR USEABLE FOR ELECTRIC SWITCHES AND THE LIKE 26 Claims, 9 Drawing Figs. v

[52] U.S.C1 .3 200/172, 267/ 1 59 [51] lnt.Cl H0lh3/l2 [50] Field of Search ZOO/102,

[56] References Cited UNlTED STATES PATENTS Primary Examiner-H. 0. Jones Attorney-Birch, Swindler, McKie & Beckett PATENTED JUN 1 I97! SHEET 1 OF 3 INVENT OR Robert H. Twyfard FIG. 3

PATENTED JUN 1 I97! SHEU 2 OF 3 /4 FIG. 5

FIG 4 ACTUATOR USEABLE FOR ELECTRIC SWITCHES AND THE LIKE BACKGROUND OF THE INVENTION This invention relates to an actuator assembly and, more particularly, to such an assembly capable of being molded in a unitary structure from a rigidly flexible, resilient, synthetic resin material for providing a spring-driven displacement of a driven member.

FIELD OF THE lNVENTlON Actuators which are capable of moving some type of driven member reciprocally to and from an operative position are employed in various manners. For instance, this type of actuator may be used in electrical switching mechanisms where contacts are moved in and out of position to make and break electric circuits or in various valve assemblies where some type of valve closure member is reciprocally movable to and from an operative position. The potential application of an actuator assembly which provides a displacement of a driven member is too broad to be fully encompassed by examples herein.

Many such actuator assemblies employ overcenter spring members to assist in moving the driven member to and from its operative position. Normally, such spring members are formed of a metallic material and are connected to the driven member and a supporting frame by various types of connection means. Such prior art assemblies provide difficult productionproblems due to the necessity of assembling the various parts of the actuator assembly resulting in extremely high production costs. Further, it is often desirable to provide very small, lightweight actuators of the nature of those which might be used in some complex electrical system to facilitate the construction of a switching bank which may include thousands of individual switching members. Naturally, the smaller the actuator assembly becomes, the more difficult and expensive its assembly.

SUMMARY OF THE lNVENTlON This invention comprises an actuator assembly capable of being unitarily formed including a frame, an overcenter spring member, a driven member, and a driver member. The overcenter spring member includes a pair of opposed spring elements, each of the elements being unitarily formed of a rigidly flexible, resilient, synthetic resin material and including a longitudinal arm and a transverse arm connected by a portion of reduced thickness forming a first hinge joint. The longitudinal arms of the spring elements have their end portions opposite said first hinge joint connected at spaced positions to the frame. Preferably, the longitudinal arms of the spring elements are integrally formed with said frame. The ends of the transverse arms opposite said first hinge joint are hingedly connected together, preferably by an integral connection comprised of a second portion of reduced thickness to provide a second hinge joint.

In order to provide the overcenter spring action, at least of the longitudinal arms is flexible and the overall length of the combined transverse arms and second hinge joint exceeds that of the spacing between the longitudinal arms whereby at least one of the longitudinal arms will be flexed outwardly when the transverse arms are moved to a center position, a position substantially normal to the longitudinal arms. The inward flexing of at least one of said longitudinal arms as the transverse arms move reciprocally past said center position drives said transverse arms outwardly from said center position with a spring action.

The driven member may be connected to the transverse arms in various manners; however, it is preferably to integrally form the driven member with a portion of the transverse arms to avoid assembly costs. The driver member may also be mounted in various manners on the frame to permit a reciprocal movement of said driver member whereby said driver member is engaged with either the driven member or the transverse spring arms for reciprocal movement of said arms over said center position. Preferably, the driver member is integrally formed with said frame by supporting said driver member on the frame by a pair of spring-biased support members. The support members are comprised of thin strips of a rigidly flexible, resilient synthetic resin material and have one end portion connected to opposite sides of the driver member and their opposite end portion connected to the frame. In this manner, the driven member can be moved in a first direction by some force and returned in a second opposite direction by the spring action of the spring-biased support member. Thus, a movement of said driver member in a first direction moves said driven member and transverse arms past said center posi tion in a first direction whereby said overcenter spring member will thrust said driven member to a first position. Then, the spring action of the support members returns said transverse arms and driven member in a second direction back past said center position and the overcenter spring member thrusts said driven member to a second position. In the illustrated embodiment shown in a switch adaptation, in the first position of the driven member, the contacts are closed and, in the second position, the contacts are open.

It is an object of this invention to alleviate the aforementioned difficulties in the art by providing a new and novel actuator assembly, capable of being formed in a unitary structure thereby materially reducing the cost of production of such actuator assemblies.

It is a further object of this invention to provide such assemblies which are molded of rigidly flexible, resilient, synthetic resin material in an integral structure to thereby form a unitary actuator assembly.

It is another object of this invention to provide such a molded assembly capable of being produced in units of extremely small dimensions in order to facilitate the use of such an actuator assembly as a switch in complex electrical equipment without unduly increasing the size or weight of such electrical equipment.

lt is a further object of this invention to provide an overcenter spring member having a pair of opposed spring elements, each of said spring elements being integrally molded and comprised ofa transverse arm and a longitudinal arm connected by a portion of reduced thickness to form a hinge joint between said arms.

It is also an object of this invention to provide such an overcenter spring member wherein the driven member of the actuator assembly is integrally formed with said transverse arms and further wherein the longitudinal arms are integrally formed with a support frame.

It is an additional object of this invention to provide such an assembly including a driver member employed for moving the transverse arms past a center position such that the spring action imparted by the longitudinal arms of the spring member springingly moves the driven member to and from an operative position.

It is also an object of this invention to provide such a driver member which is integrally connected to the frame and engageable with the driven member for imparting a driving force to said driven member for moving the transverse arms of the spring member past the center position.

It is a further object of this invention to provide such a unitary actuator assembly for use in a rubber stamp printing assembly wherein the driven member has raised type characters on its lowermost surface.

It is another object of this invention to provide such a single and integral assembly wherein there are provided cooperative means on the driver member and the driven member to form a lost motion connection between said members and wherein said driver member is supported in a spring-biased manner on said frame such that the driver and driven members and the transverse arms are returned to a second position by the spring action of said spring-biased support members after movement of said members and transverse arms to a first position whereby said transverse arms are positioned on one side of said center position in said first position and the opposite side of said center position in said second position.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein an embodiment of this invention is set forth by way ofillustration and example.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a front elevational view of an actuator assembly encompassing the features of this invention illustrated as an electrical switch with the driver and driven members disconnected and disposed in an outwardly extended position.

FIG. 2 is a rear elevational view of a portion of the actuator assembly illustrated in FIG. 1.

FIG. 3 is a fragmentary horizontal sectional view taken on line 3-3 of FIG. 2.

FIG. 4 is a sectional view taken on line 4-4 of FIG. 1.

FIG. 5 is a top plan view of the actuator assembly shown in FIG. 1.

FIG. 6 is a front elevational view of the actuator assembly of FIG. I showing the driver and driven members operatively engaged and the driven member disposed in an inoperative position with the contacts of the switch open.

FIG. 7 is a front elevational view of the actuator assembly shown in FIG.-1 depicting in broken lines the position of the driven member in an operative position closing the switch contacts.

FIG. 8 is a partial front elevational view similar to FIG. 1 illustrating an alternative embodiment.

FIG. 9 is a partial front elevational view similar to FIG. 1 showing a further alternative embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, an actuator assembly I embodying the features of this invention is illustrated as an actuator assembly for use in an electrical switch to actuate a connector bar or arm to and from contacting relation with at least a pair of electrical contacts. The illustrated assembly I is unitarily formed of a suitable rigidly flexibly, resilient synthetic resin material such as a normally solid polypropylene having the desired degree of resilience. While the actuator assembly I provides numerous advantages when employed in an electrical switching arrangement, its uses are varied and, therefore, there is no intention to limit this invention to an electrical switch.

Referring to FIG. I, the actuator assembly 1 is broadly comprised of a frame 2, an overcenter spring member 4, a driven member illustrated herein as an electrical connector bar holder 6, a driver member 8, and a pair of

support members

10 and 12 for retaining the driver member 8 in a reciprocally movable, spring-biased position on the frame 2.

Referring to FIGS. 1 and 4, the frame member 2 may take various forms depending upon the mounting requirements ofa particular actuator in a particular environment In the illustrated embodiment, the frame is comprised of a pair of opposed, spaced

leg members

14 and 16.

A base portion 18 of the frame member 2 interconnects the

legs

14 and 16 and defines a centrally located vertical through bore 20 in which the driver member 8 and the connector bar holder 6 are reciprocally movable.

As illustrated in FIG. I, the overcenter spring member 4 is comprised of a pair of

opposed spring elements

22 and 24. The

spring elements

22 and 24 are each comprised of a thin strip of the rigidly flexible, resilient synthetic resin material comprising the actuator assembly I. The

spring elements

22 and 24 each include a longitudinal arm 26, a transverse arm 28, and a portion of reduced thickness between said

arms

26 and 28, forming a first hinge joint 30. The end portions 32 of the longitudinal arms 26 opposite the hingcjoint 30 connected at spaced points to the base 18 of the frame 2. While it is contemplated that other types of connections may be employed for securing the overcenter spring member 4 to a frame, it is preferable that the end portions 32 be integral with the frame 2. The connection points of the longitudinal arms 26 to the frame 2 are spaced apart a distance less than the overall length of the combined and connected transverse arms 28 of the

opposed spring elements

22 and 24 such that a movement of the transvers arms 28 to a center position wherein they are substantially normal to the longitudinal arms 26 causes arms 26 to flex outwardly as shown in FIG. 7. In this manner, when the transverse arms 28 pass the center position, the longitudinal arms 26 will flex inwardly imparting a spring-driven action to the driven member or connector bar holder 6.

A second hinge joint 34 is provided between the transverse arms 28 of the

opposed spring elements

22 and 24 whereby the relative angular position of the transverse arms 28 to one another may be varied as the transverse arms 28 are moved reciprocally over the center position. As illustrated, a pair of second hinge joints 34 are provided on opposed sides of the connector bar holder 6 by the end portions 36 of the transverse arms 28 which are ofa reduced thickness. As illustrated, the end portions 36 of the transverse arms 28 are integral with said bar holder 6. Thus, by moving the connector bar holder 6 in a first direction, slightly past the aforementioned center position, the spring action imparted by the flexing of the Ion gitudinal arms 26 thrusts the transverse arms 28 and the connector bar holder 6 in said first direction under a spring action. Likewise a movement of the transverse arms 28 past the center position in a second opposite direction produces a spring-driven movement of the bar holder 6 in said second direction thereby providing a connector bar holder 6 movable reciprocally to first and second positions wherein the transverse arms 28 are disposed on opposite sides of the aforementioned center position respectively.

While the aforedescribed assembly of longitudinal and

transverse arms

26 and 28 respectively permit a linear displacement of the connector bar holder 6, it is contemplated that other types of arrangements using a substantially similar overcenter spring member 4 may be employed for providing other types of displacement, such as an arcuate movement of the connector bar holder 6 between first and second positions. This could be accomplished by forming or otherwise connecting the transverse arm 28 of the spring element 24 with the adjacent leg member 14 of the frame 2 and providing a portion of reduced thickness between the transverse arms 28 and the leg 14. In this manner, movement of the transverse arm 28 to a center position would cause only an outward flexing of the single longitudinal arm 26 of the spring element 22. This type of arrangement would produce an arcuate displacement of the connector bar holder 6 having a radius defined by the transverse arm 28 of the spring element 24. Thus, it is contemplated that a transverse arm of one of the spring elements may have its associated first hinge joint connected to the frame 2 either with or without the interposition therebetween of a longitudinal arm. Such an alternative construction is illustrated on FIG. 8. In addition, it is contemplated that the

spring elements

22 and 24 while in themselves being formed ofa single piece of rigidly flexible, resilient synthetic resin material could be connected by various means to the frame and together to form the overcenter spring member 4. Certainly, however, a tremendous advantage is obtained by forming a unitary structure thereby eliminating all assembly costs.

An actuator assembly 1 may also be provided by utilizing only one spring element either 22 or 24 in opposed relation to a guide means. Such a guide means would replace one of the spring elements and provide a sliding abutment surface against which the driven member 6 would be spring biased by the other spring element. The abutment surface of the guide means would be spaced from the longitudinal arm of the opposed spring element a distance less than the length of the driven member and the transverse arm whereby movement of the transverse arm to a center position would flex the longitudinal arm outwardly as previously discussed. Such a further alternative embodiment is generally illustrated on FIG. 9.

With further reference to FIG. I, the driven member of electrical connector bar holder 6 includes a stem portion 40 and a connector bar mounting portion 42. In the illustrated embodiment, the connector bar holder is illustrated as substantially T-shaped with the stem portion 40 of the T being integral with the end portions 36 of the opposed transverse arms 28 of the

spring elements

22 and 24. The mounting portion 42 includes a recess 44 defined by outwardly beveled sidewalls 46 in which a corresponding beveled connector bar 48 capable of providing an electrical flow path is inserted. To obtain added guiding of the reciprocating movements of holder 6, the mounting portion 42 may be a length to slidingly engage with the inwardly facing surfaces of

leg members

14 and 16 with these surfaces formed to be parallel with each other.

While various means may be employed for moving the transverse arms 28 and the connector bar holder 6 reciprocally past the center position in order to acquire the springing action of the longitudinal arms 26, it is particularly desirable to provide a driver member 8 which is integral with the frame and engageable with the transverse arms 28 and/or the connector bar holder 6 to eliminate the costly expense of the assembling the various parts into an actuator assembly.

Further referring to FIG. I, the driver member 8, as illus I trated, is integrally connected to the frame 2 by means of a pair of opposed spring-biased supporting

members

10 and 12. The support members I0 and 12 permit the driver member 8 to move downwardly through the bore in engagement with the connector bar holder 6 in a manner to be later described thereby driving the transverse arms 28 past a center position whereby the overcenter spring member 4 thrusts he connector bar 48 downwardly into connecting relation with a pair of electrical contacts 50 (Shown on FIGS. 6 and 7). As illustrated in FIG. 7, the movement of the driver member 8 in this manner causes the

support members

10 and 12 to fold in an accordion fashion. The actuator assembly I is provided with various means for spring biasing the supporting

members

10 and 12, to be described, whereby the return of the connector bar holder 6 and the transverse arms 28 in an opposite direction past the center position is effected by the spring action of the support members 10 and I2.

Referring again to FIG. I, each of the

support members

10 and 12 are preferably comprised of thin strips of the rigidly flexible, resilient synthetic resin material used in the overall assembly, said strips having first, second, and

third portions

52, 54, and 56 respectively. The first and

second portions

52 and 54, respectively, are connected by a portion of reduced thickness defining a third hingejoint S8. The second and

third portions

54 and 56 of the

support members

10 and 12 are connected by another portion of reduced thickness defining a fourth hinge joint 60. In addition, the first and

third portions

52 and 56 are connected by portions of reduced

thickness

62 and 64 to spaced positions on the frame 2 and to opposed sides of the driver member 8 respectively. While it is contemplated that other and different support members 10 and I2 may be employed which may use more or less portions and hinge joints, the embodiment illustrated herein is preferred.

The support members I0 and 12 are biased by the use of various abutment surfaces which come into an abutting contact when the

support members

10 and 12 are folded into the accordion position illustrated in FIG. 7. The frame member 2 is provided with a shoulder 66 defining an abutment surface positioned adjacent the connection thereto of the first portions 52 of the support members 10 and I2 and directly beneath said portions 52. The shoulder 66 engages the first portion 52 when it is folded as shown in FIG. 7, forming a fulcrum about which the portion 52 is bent whereby the rigidly flexible, resilient nature of the striplike portion 52 effects an upward spring action which assists in causing the connector bar holder 6 to be withdrawn from its first operative position.

In addition, a pair of shoulders 68 on the driver member 8 are provided for defining abutment surfaces. The shoulders 68 are positioned in overlying relation to he third portion 56 of each of the

support members

10 and 12 and outwardly thereof. The shoulders 68 abut said third portions 56 when the

support members

10 and 12 are folded into the position illustrated in FIG. 7. Again, the abutment surface of the shoulders 68 provides a fulcrum point about which the striplike, flexible third portions 56 of the

support members

10 and 12 are caused to bend by the downward driving springing force of the overcenter spring member 4. Thus, the bent portions 56 provide an upward spring force to assist in the return of the trans verse arms 28 past said center position such that the overcenter spring member 4 may again be operative to thrust the transverse arm members 28 to a second position on the opposite side of said center position.

In order to provide a further upward driving force, abutment surfaces are defined as raised portions 70 on each of the

individual portions

52, 54, and 56 of the

support members

10 and 12 directly adjacent the portions of reduced thickness forming the third and fourth hinges 58 and 60 respectively. These raised abutment surfaces on the

portions

52, 54, and 56 respectively are provided on the sides of said

portions

52, 54, and 56 which are moved toward another portion upon the hinging of the support members 10 and I2. Thus, the raised portions 70 on the first and

second portions

52 and 54 are moved into an abutting relation and the raised portions 70 on the

portions

54 and 56 are also moved into abutting relation providing fulcrum points directly adjacent the third and fourth hinges 58 and 60 which tend to flex the

individual portions

52, 54, and 56 and thereby impart an upward driving force to assist in returning the connector bar holder 6 to its second inoperative position.

In the illustrated embodiment, cooperative means are provided on the connector bar holder 6 and the driver member 8 for forming a lost motion connection 77. As illustrated, the driver member 8 defines an open-ended slot 76 having a neck portion and an enlarged interior end portion 78. The end of the stem portion 40 of the connector bar holder 6 is complimentarily shaped to slot 76 having a width in excess of the neck portion 75 of the slot 76. In this manner, the end 80 of the connector bar holder 6 is free to move vertically in the enlarged portion 78 of the slot 76 in such a manner that the upper wall 82 of the slot portion 78 provides a force transfer surface against the upper surface 84 of the end 80 for imparting a driving force to the connector bar holder 6 to move it downwardly past the center position. Ledges 86 are provided on opposed sides of the enlarged portion 78 which engage lips 88 on the end 80 in order to impart a driving force to the connector bar holder 6 forlifting the connector bar holder 6 from its said first operative position to and past the center position of the transverse arms 28.

Referring to FIGS. 6 and 7, the actuator assembly 1 is illustrated in the embodiment of an electrical switch and employed for linear displacement of the connector bar 48 toand from first and second, operative and inoperative, positions, respectively, in order to make and break, respectively an electrical circuit.

In order to operate the actuator assembly I, the driver member 8 is merely depressed in the manner shown by the arrow in FIG. 7 and moved downwardly thereby folding the

support members

10 and 12 in the manners illustrated in FIGS. 6 and 7. The downward thrust of the driver member 8 causes the

force transfer surface

82 and 84 of the lost motion connection 77 to come into abutting contact, thereby forcing the connector bar holder 6 downwardly to the aforementioned center position. The location of the various parts in the center position is illustrated in FIG. 7 by solid lines. The outwardly flexed position of the longitudinal arms 26 as the driving force moves the transverse arms 28 past the center position is also shown in solid lines in FIG. 7. The inward flexing of the longitudinal arms 26 as the transverse arms pass the center position drives the connector bar holder 6 downwardly with the enlarged end portion 80 of the stem portion 40 of the connector bar holder6 moving through the enlarged portion 78 ofthe slot 76 placing the connector bar 48 in contacting relation with the contacts 50. Thus, the actuator assembly 1 is positioned in its first and operative position.

The downward thrust of the connector bar holder 6 by the overcenter spring member 4 has caused the portions of the support members and 12 to be flexed in the manner previously described by the various abutment surfaces 66, 68, and 70 such that the spring action of the flexible

striplike portions

52, 54, and 56 of the

support members

10 and 12 cause an upward thrusting of the driver member 8. This flexing causes the

support members

10 and 12 to return the transverse arms 28 back past the center position whereupon the inward flexing of the longitudinal arms 26 drives the transverse arms 28 upwardly to move the holder 6 to its second and inoperative position. Even if the abutment surfaces 66, 68 and 70 are omitted, the inherent resiliency of the material forming

support members

10 and 12 is such that the support members bias the driver member 8 to the original position in which the support members were molded or otherwise formed. Thus, when the support members are deformed from this original position, the flexing of the synthetic resin material at the hinge joint 58, 60, 62, and 64 of

support members

10 and 12 from its original state imparts stresses thereto which, when the force applied to drive member 8 is released, tend to urge the driver member back to its original position and, of course, through connection 77 tend to return connector bar holder 6 to its second position.

Certainly it is contemplated that this assembly may be used in various embodiments wherein various types of driver members are employed for the movement of driven member 8 and the transverse arms 28 reciprocally past the center position of the transverse arms 28. In addition, driver members may be employed which are not spring biased and certainly other types of spring-biasing mechanisms may be employed other than that employed in the

support members

10 and 12. it has been found, however, that the particular embodiment disclosed herein has special advantages primarily in that it can be formed from a single, integral piece of rigidly flexible, resilient, synthetic resin material thereby materially decreasing the production costs attendant such an actuator assembly and materially decreasing the weight and overall size require ments for such an actuating assembly. These characteristics make this actuator particularly adaptable for use in electrical equipment where size and weight are critical.

One other specific use for the actuator assembly of this invention may be mentioned. The support portion 42 of holder 6 may carry on its bottom face-type characters such as employed on the commonly known rubber stamp devices. Then, the snap action of the actuator assembly can effectively be used to imprint the type characters on paper or other printable material disposed below the ends ofleg

members

14 and 16.

ln a rubber stamp application, the device, combining the actuator assembly with appropriately formed raised-type characters on the bottom of support portion 42, is disposed with

leg members

14 and 16 resting on the material to have the stamp applied thereto. Then driver member 8 is manually depressed. When the transverse arms 28 move past the center position, thereafter the flexed longitudinal arms 26 thrust transverse arms 28 and holder 6 downwardly impressing the type characters against the material with an even, uniform pressure. Using such an actuator assembly applies the stamp impression with the same force each action such that the imprint appears the same on the material each time of actuation.

This stamp application is particularly advantageous where the raised type characters are formed of an ink-retaining material such that no ink pad is needed to ink the stamp prior to each impression being made but instead numerous impressions can be made from the ink entrained in the material ofthe stamp.

It is to be understood that the form of this invention herein shown and described is to be taken as a preferred example of the invention and various changes and modifications in the arrangement of parts and the interconnection of components may be resorted to without departing from the spirit ofthe invention or the scope of the appended claims. All such variations and modifications which come within the spirit and scope of the appended claims are intended to be included herein as fully and completely as if they had been specifically illustrated, described, and claimed. Thus, the modifications specifically disclosed are exemplary only and not intended to be limiting on the scope of the invention. The scope of the invention is defined by the following claims:

What I claim is:

1. An actuator apparatus comprising:

a frame an overcenter spring member including first and second opposed spring elements each of said opposed spring elements unitarily formed of a rigidly flexible, resilient, synthetic resin material, said first spring element including a longitudinal arm and a transverse arm connected by a portion of reduced thickness forming a first hinge joint between said arms said longitudinal arm having its end portion opposite said first hinge joint connected to said frame, said second spring element including at least a transverse arm and a portion of reduced thickness at one end thereof also defining a first hinge joint, said second spring element having means connecting its hingejoint to said frame, the end portion opposite said first hinge joint of one of said transverse arms hingedly connected to the end portion of the other transverse arm opposite said first hinge joint with the length of the combined transverse arm being greater than the spacing between the first hinge joints of the opposed spring elements and said longitudinal arm being flexible whereby said longitudinal arm will be flexed outwardly when said transverse arms are moved to a center position and the inward flexing of said longitudinal arm moves said transverse arms reciprocally past said center position with a spring action.

2. An apparatus as recited in claim 1 further including means operatively associated with said overcenter spring member for reciprocally moving said combined transverse arms over said center position whereby the springing action of said overcenter spring member will thrust said transverse arms to first and second positions.

3. An apparatus as recited in claim 1 wherein said opposed spring elements are integrally formed in a single piece including a portion of reduced thickness interconnecting said transverse arms forming a second hinge joint therebetween.

4. An apparatus as recited in claim 1 including a driven member operatively connected to at least one of said transverse arms for movement therewith whereby reciprocal movement of the transverse arms past said center position will thrust said driven member to and from first and second positions respectively.

5. An apparatus as recited in claim 4 wherein said driven member is integral with said overcenter spring member and wherein the end portions of said transverse arms opposite said first hinge joints are of a reduced thickness and are integrally connected to opposite sides of said driven member thereby forming second hinge joints connecting the transverse arms to said driven member.

6. An apparatus as recited in claim 5 further including a driver member with cooperative means on said driver member and said driven member for forming a lost motion connection between said driver and driven members, and spring-biased support means operatively connected to said frame for returning said driver member and thereby said transverse arms and said driven member past said center position to one of said operative or inoperative positions after movement of said transverse arms and said driven member in an opposite direction past said center position to said other position.

7. An apparatus as recited in claim 6 wherein said springbiased support means includes a pair of spaced, flexible striplike support members each of said support members comprised of a single integrally formed piece of rigidly flexible resilient synthetic resin material having opposed end portions, said end portions of each of said support members connected respectively to said frame at spaced positions and to opposed sides of said driver member, each of said support members having at least first, second, and third portions, said first and second portions connected by a portion of reduced thickness forming a third hingejoint, said second and third portions connected by a portion of reduced thickness in a fourth hinge joint.

8. An apparatus as recited in claim 7 wherein said springbiased support means further includes means on said frame underlying said first portion of each of said support members adjacent the connection point of said support member to said frame for engaging a part of said first portion of the support member to form a fulcrum limiting the inward movement of said first portion towards said frame and about which said flexible portion is bent causing said first portion to act as a flexible spring member.

9. The apparatus as recited in claim 8 wherein said springbiased support means further includes a pair of abutment means on said driver member adjacent the connection prints of said support members to said driver member and outwardly of said third portion of said support members for abutting engagement with a part of said third portion to thereby flex said third portion forming a flexible spring member.

l0. An apparatus as recited in claim 9 wherein the portions of each of said support members include a raised abutment surface adjacent each of the portions of reduced thickness forming the third and fourth hinge joints, said abutment surface being located on the side of said portions of said support members which are moved toward one another upon the hinging of said support members whereby said raised surfaces on said first and second portions abut and said raised surfaces on said second and third portions abut thereby limiting the movement of said portions inwardly of one another and spring biasing said support members.

11. An apparatus as recited in claim 1 wherein said frame and said overcenter spring member are integral.

12. An apparatus as recited in claim 11 further including spring-biased driver means integral with said frame and said overcenter spring member and displaceable in such a manner as to reciprocally move said transverse arms past said center position, said driver-member being moved in a first direction to move said transverse arms past said center position whereby said transverse arms are thrust in a first direction, said drivermeans including spring means for moving said driver means and said transverse arms in a second opposite direction back past said center position.

13. A apparatus as recited in claim 1 further including an electrical connector bar operatively connected to said transverse arms and reciprocally movable with said transverse arms whereby said connector bar may be moved into contacting relation with at least a pair of spaced electrical contacts to complete and electrical flow path across said contacts to provide an electrical switch.

14. An apparatus as recited in claim 13 including a connector bar holder integrally formed with said transverse arms, connector bar holder having mounting means thereon for retaining said connector bar thereto.

15. An apparatus as recited in claim 14 wherein said connector bar holder includes a stem portion interposed between said transverse arms and integral with said transverse arms, each of said transverse arms including an end portion adjacent said stem portionof reduced thickness forming second hinge joints, said connector bar holder including a mounting portion integral with said stem portion and including means thereon for retaining said connector bar thereto.

16. An apparatus as recited in claim 15 wherein said frame and said overcenter spring member are integrally formed.

17. An apparatus as recited in claim 16 further including a driver means integrally formed with said frame and said overcenter spring member and engageable with said stem portion of said connector bar holder in such a manner as to reciprocally move said connector bar holder and transverse arms past said center position whereby said connector bar is springingly moved into contacting relation with said contacts.

18. An apparatus as recited in claim 17 further including a cooperative means on said driver member and said stem portion of said connector bar holder for forming a lost motion connection between said connector bar holder and said driver member, and spring-biased support means operatively connected to said frame for returning said driver and driven members to a second position after the movement of said driver and driven members to a first position wherein said transverse arms are positioned on opposite sides of said center position when said driver and driven members are in said first and second positions respectively.

19. An apparatus recited in claim 18 wherein said springbiased support means includes a pair of spaced flexible support members each of said support members comprised of a single integrally formed piece of rigidly flexible, resilient synthetic resin material having opposed end portions, said end portions of each of said support members connected respectively to said frame at spaced positions and to opposed sides of the driver member, each of said support members having at least first, second, and third portions, said first and second portions connected by a portion of reduced thickness forming a third hinge joint, said second and third portions connected by a portion of reduced thickness in a fourth hinge joint.

20 An apparatus as recited in claim 19 wherein said springbiased support means further includes means on said frame underlying said first portion of each of said support members adjacent the connection point of said support members to said frame for abutment ofa part of said first portion of the support member to form a fulcrum limiting the inward movement of said first portion towards said frame and thereby causing said first portion to act as a flexible spring member.

21. An apparatus as recited in claim 20 wherein said springbiased support means further includes a pair of means on said driver member adjacent the connection points of said support members to said driver member and outwardly of said third portion of said support members for abutting engagement with a part of said third portion of said driver member to form a fulcrum to thereby limit the outward movement of said third portion away from said driver member thereby causing said third portion to act as a flexible spring member.

22. An apparatus as recited in claim 21 wherein the portions of each of said support members includes a raised abutment surface adjacent each of the portions of reduced thickness forming the third and fourth hinge joints, said abutment surface being located on the side of said portions of said support members which are moved toward one another upon the hinging of said support members whereby said raised portions on said first and second portions abut and said raised members said second and third portions abut thereby limiting the movement of said portions inwardly of one another and spring biasing said support members to assist in providing for the spring biasing retention of the driver member.

23. An apparatus as recited in claim 1 further including at least a pair of spaced electrical contacts operatively associated with said overcenter spring member and an electrical connector bar operatively connected to said transverse arms and reciprocally movable with said transverse arms into contacting relation with said contacts to complete an electrical flow path across said contacts thereby forming an electrical switch.

24. An apparatus as recited in claim 1 wherein said rigidly flexible, resilient, synthetic resin material is a polypropylene.

25. An apparatus as recited in claim 1 wherein said opposed spring elements each include a longitudinal arm and a transverse arm with a portion of reduced thickness therebetween defining a first hinge joint and wherein said longitudinal arms have their end portions opposite said first hinge joints connected to said frame.

26. An actuator apparatus comprising:

a frame a driven member an overcenter spring member including at least one spring element, said spring element unitarily formed of a rigidly flexible, resilient, synthetic resin material and including a path of movement, the spacing between the first hinge joint and said movement path of said driven member being such that said longitudinal am will be flexed out wardly when said transverse arm is moved to a center position and the inward flexing of said longitudinal arm moves said transverse arm reciprocally past said center position with a spring actions.

Claims

1. An actuator apparatus comprising: a frame an overcenter spring member including first and second opposed spring elements each of said opposed spring elements unitarily formed of a rigidly flexible, resilient, synthetic resin material, said first spring element including a longitudinal arm and a transverse arm connected by a portion of reduced thickness forming a first hinge joint between said arms said longitudinal arm having its end portion opposite said first hinge joint connected to said frame, said second spring element including at least a transverse arm and a portion of reduced thickness at one end thereof also defining a first hinge joint, said second spring element having means connecting its hinge joint to said frame, the end portion opposite said first hinge joint of one of said transverse arms hingedly connected to the end portion of the other transverse arm opposite said first hinge joint with the length of the combined transverse arm being greater than the spacing between the first hinge joints of the opposed spring elements and said longitudinal arm being flexible whereby said longitudinal arm will be flexed outwardly when said transverse arms are moved to a center position and the inward flexing of said longitudinal arm moves said transverse arms reciprocally past said center position with a spring action.

7. An apparatus as recited in claim 6 wherein said spring-biased support means includes a pair of spaced, flexible striplike support members each of said support members comprised of a single integrally formed piece of rigidly flexible resilient synthetic resin material having opposed end portions, said end portions of each of said support members connected respectively to said frame at spaced positions and to opposed sides of said driver member, each of said support members having at least first, second, and third portions, said first and second portions connected by a portion of reduced thickness forming a third hinge joint, said second and third portions connected by a portion of reduced thickness in a fourth hinge joint.

8. An apparatus as recited in claim 7 wherein said spring-biased support means further includes means on said frame underlying said first portion of each of said support members adjacent the connection point of said support member to said frame for engaging a part of said first portion of the support member to form a fulcrum limiting the inward movement of said first portion towards said frame and about which said flexible portion is bent causing said first portion to act as a flexible spring member.

9. The apparatus as recited in claim 8 wherein said spring-biased support means further includes a pair of abutment means on said driver member adjacent the connection prints of said support members to said driver member and outwardly of said third portion of said support members for abutting engagement with a part of said third portion to thereby flex said third portion forming a flexible spring member.

10. An apparatus as recited in claim 9 wherein the portions of each of said support members include a raised abutment surface adjacent each of the portions of reduced thickness forming the third and fourth hinge joints, said abutment surface being located on the side of said portions of said support members which are moved toward one another upon the hinging of said support members whereby said raised surfaces on said first and second portions abut and said raised surfaces on said second and third portions abut thereby limiting the movement of said portions inwardly of one another and spring biasing said support members.

12. An apparatus as recited in claim 11 further including spring-biased driver means integral with said frame and said overcenter spring member and displaceable in such a manner as to reciprocally move said transverse arms past said center position, said driver-member being moved in a first direction to move said transverse arms past said center position whereby said transverse arms are thrust in a first direction, said driver means including spring means for moving said driver means and said transverse arms in a second opposite direction back past said center position.

15. An apparatus as recited in claim 14 wherein said connector bar holder includes a stem portion interposed between said transverse arms and integral with said transverse arms, each of said transverse arms including an end portion adjacent said stem portion of reduced thickness forming second hinge joints, said connector bar holder including a mounting portion integral with said stem portion and including means thereon for retaining said connector bar thereto.

19. An apparatus as recited in claim 18 wherein said spring-biased support means includes a pair of spaced flexible support members each of said support members comprised of a single integrally formed piece of rigidly flexible, resilient synthetic resin material having opposed end portions, said end portions of each of said support members connected respectively to said frame at spaced positions and to opposed sides of the driver member, each of said support members having at least first, second, and third portions, said first and second portions connected by a portion of reduced thickness forming a third hinge joint, said second and third portions connected by a portion of reduced thickness in a fourth hinge joint. 20 An apparatus as recited in claim 19 wherein said spring-biased support means further includes means on said frame underlying said first portion of each of said support members adjacent the connection point of said support members to said frame for abutment of a part of said first portion of the support member to form a fulcrum limiting the inward movement of said first portion towards said frame and thereby causing said first portion to act as a flexible spring member.

21. An appaRatus as recited in claim 20 wherein said spring-biased support means further includes a pair of means on said driver member adjacent the connection points of said support members to said driver member and outwardly of said third portion of said support members for abutting engagement with a part of said third portion of said driver member to form a fulcrum to thereby limit the outward movement of said third portion away from said driver member thereby causing said third portion to act as a flexible spring member.

26. An actuator apparatus comprising: a frame a driven member an overcenter spring member including at least one spring element, said spring element unitarily formed of a rigidly flexible, resilient, synthetic resin material and including a longitudinal arm and a transverse arm connected by a portion of reduced thickness forming a first hinge joint between said arms, the longitudinal arm of the spring element having its end portion opposite said first hinge joint connected to said frame, the end portion opposite said first hinge joint of said transverse arm hingedly connected to said driven member, and means opposite said spring element for guiding said driven member along a desired path of movement, the spacing between the first hinge joint and said movement path of said driven member being such that said longitudinal am will be flexed outwardly when said transverse arm is moved to a center position and the inward flexing of said longitudinal arm moves said transverse arm reciprocally past said center position with a spring actions.