US3602681A

US3602681A - Adjustable actuator arm construction

Info

Publication number: US3602681A
Application number: US15689A
Authority: US
Inventors: Ralph W Finke
Original assignee: Robertshaw Controls Co
Current assignee: Robertshaw Controls Co
Priority date: 1970-03-02
Filing date: 1970-03-02
Publication date: 1971-08-31
Anticipated expiration: 1988-08-31

Abstract

A first arm member is secured to a control shaft of a device that is to be controlled by the arm construction. A second arm member is pivotally mounted to the first arm member. The first arm member rotatably carries a threaded adjusting screw that has an adjusting member threaded thereon and is operatively associated with opposed surface means of the second arm member to pivot the second arm member relative to the first arm member in relation to the axial position of the adjusting member on the adjusting screw. The adjusting member has resilient means wedged between the opposed surface means of the second arm member in all adjusted positions thereof to eliminate play therebetween.

Description

United States Patent 2,906,842 9/1959 Brin ZOO/172 A 3,29l,953 12/1966 Luik 200/172 A 3,303,298 2/1967 Dobes v. ZOO/47 R Primary Examiner-H. 0. Jones V Attorneys-Auzville Jackson, Jr., Robert L. Marben and Candor, Candor & Tassone ABSTRACT: A first arm member is secured to a control shaft of a device that is to be controlled by the arm construction. A second arm member is pivotally mounted to the firstarm member The first arm member rotatably carries a threaded adjusting screw that has an adjusting member threaded thereon and is operatively associated with opposed surface means of the second arm membe'r to pivot the second arm member relative to the first arm member in relation to the axial position of the adjusting member on the adjusting screw. The adjusting member has resilient means wedged between the opposed surface means of the second arm member in all adjusted positions thereof to eliminate play therebetween.

- ATEN'IED AUB31 lsn SHEET 1 OF v2 FIG.4

INVENTOR. RALPH w. FINKE HIS ATTORNEYS ADJUSTABLE ACTUATOR ARM CONSTRUCTION This invention relates to an adjustable actuator arm construction for actuating a device in relation to the movement of the arm construction relative thereto.

It is well known that adjustable actuator arm constructions have been provided in the past for electrical switches and the like wherein one part of the arm construction is interconnected to a control shaft for the electrical switch or the like and the other part of the arm construction carries a roller means against which an operating device will engage to move the arm construction and if such movement is sufficient, the arm construction will cause operation of the electrical switch either to its on position or to its off position as the case may be.

Such prior known actuator arm constructions have means for adjusting the roller part of the arm construction relative to the part thereof that is fixed to the control shaft of the electrical switch in order to properly position the roller of the arm construction relative to the device that is to engage the same so that accurate control can be produced by a limit switch or the like.

Accordingly, it is a feature of this invention to provide an improved adjustable actuator arm construction for the above purpose as well as for other purposes as desired.

In particular, one feature of this invention is to provide an adjustable arm construction which will eliminate play between the two adjustable parts thereof while absorbing excess shock therebetween and facilitating adjustable movement therebetween.

In particular, one embodiment of the adjustable actuator arm construction of this invention comprises a first arm member being secured to the control shaft of the device that is to be operated by the arm construction. A second arm member is pivotally mounted to the first arm member and has an opening defining opposed spaced surface means thereof. The first arm member rotatably carries a threaded adjusting screw that has an adjusting member threaded thereon and being operatively associated with the opposed surface means of the second arm member to pivot the second arm member relative to the first arm member in relation to the axial position of the adjusting member on the adjusting screw. Means are provided for fastening the arm members together in the desired adjusted position thereof. The adjusting member car ries a plastic rod having opposed ends wedged between the opposed surface means of the second arm member in all adjusted positions thereof to eliminate play between the adjusting members and the second arm member for the above described reasons.

Accordingly,'it is an object of this invention to provide an improved adjustable actuator arm construction having one or more of the novel features set forth above or hereinafter shown or described.

Another object of this invention is to provide an improved device carrying such an arm construction.

Other objects, uses and advantages of this invention are apparent from a reading of this description which proceeds with reference to the accompanying drawings forming a part thereof and wherein:

FIG. I is a perspective view of the improved control device of this invention.

FIG. 2 is a fragmentary, enlarged front view of the adjustable actuator arm construction of the device ofFIG. 1.

FIG. 3 is a view similar to FIG. 2 and illustrates the arm construction partially in cross section.

FIG. 4 is a cross sectional view taken substantially on line 44 of FIG. 3.

FIG. 5 is a fragmentary, cross-sectional view taken substantially on line 5-5 of FIG. 4.

FIG. 6 is a view similar to FIG. 5 and illustrates the arm construction in a different adjusted position thereof.

FIG. 7 is an exploded perspective view of the various parts of the arm construction ofthis invention.

While the various features of this invention are hereinafter described and illustrated as being particularly adapted to provide an adjustable arm construction for an electrical switch mechanism, it is to be understood that the various features of this invention can be utilized singly or in any combination thereof to provide an arm construction for other devices as desired.

Therefore, this invention is not to be limited to only the embodiment illustrated in the drawings, because the drawings are merely utilized to illustrate one of the wide variety of uses of this invention.

Referring now to FIG. 1, the improved control device of this invention is generally indicated by the reference numeral 10 and comprises an electrical switch housing 11 containing electrical switch means in a conventional manner with the switch means having a rotatably supported actuator shaft 12, FIG. 4, projecting therefrom and having a reduced cylindrical portion 13 adapted to be coupled to the adjustable actuator arm construction of this invention that is generally indicated by the reference numeral 14 in the drawings.

As illustrated in FIGS. 1-4 and 7, the adjustable actuator arm construction 14 comprises two

arm members

15 and 16 adapted to be assembled together for pivotal movement therebetween by a threaded fastening member 17 projecting through an opening 18 in the arm member 16 and being threadably received in a threaded opening 19 in the upper end 20 of the arm member 15. The fastening member 17 has a frustoconical end portion 21 adapted to mate with a frustoconical section 22 of the opening 18 in the arm member 16 while a cylindrical portion 23 of the fastening member 17 mates with a cylindrical portion 24 of the opening 18. In this manner, with the fastening member 17 being threaded in the opening 19 of the arm member 15 and while being loose in the opening 18 of the arm member 16, the arm member 16 can be pivoted or fulcrumed on the cylindrical portion 23 of the fastening member 17 relative to the arm member 15 for ad-.

justment purposes therebetween as I will be apparent hereinafter. However, once the pivotal position of the arm member 16 relative to the arm member 15 has been obtained, subsequent tightening of the fastening member 17 causes the frustoconical portion 21 thereof to compact into the frustoconical portion 22 of the opening 18 of the arm member 16 to securely fasten the

arm members

15 and 16 together so that further pivotal movement therebetween cannot be obtained until the fastening member 17 is sufficiently loosened.

The upper end 20 of the arm member 15 is substantially arcuate and defines a semicylindrical portion 25 that is concentric about the opening 19 passing therethrough and mates with a semicircular concave part 26 of the arm member 16 to permit the aforementioned pivotal movement therebetween.

The upper end 27 of the arm member 16 pivotally carries a roller means 28 in a conventional manner whereby engagement of the roller 28 by an operating device, such as a movable part of an apparatus, will cause the arm construction 14 to move relative to the housing means 11 and, thus, rotate the control shaft 12 so that if such movement of the arm construction 14 relative to the housing 11 is sufficient, the control shaft 12 will operate the electrical switch construction within the housing 11 by either turning off the same or turning on the same as the case may be.

The arm member 15 has a cylindrical opening 29 passing therethrough to telescopically receive the cylindrical projection 13 of the control shaft 12 as illustrated in FIG. 4. A transverse opening 30 passes through the arm member 15 and intersects with the opening 29 to receive a cylindrical pin 31 having a threaded end 32 and a cutout portion 33 that will mate with the opening 29 to conform to the configuration of the cylindrical part 13 of the control shaft 12 when the pin 31 has the cutout 33 aligned with the opening 29. However, subsequent rotation of a nut 34 on the threaded end 32 of the pin 31 against the side 35 of the arm member 15 will cause the pin 31 to shift its cutout 33 out of register with the opening 29 to the right in FIG. 3 so as to provide a wedging relation with the control shaft 13. In this manner the pin 31 positively fixes the arm construction on the control shaft 13 to move in unison therewith.

The lower end 36 of the arm construction 16 is bifurcated or forked to define two depending spaced apart

parts

37 and 38 respectively defining an opening 39 therebetween as well as opposed facing

surfaces

40 and 41 for a purpose hereinafter described.

A recess or slot 42 is provided in the front surface 48 of the arm member 15 with the same having opposed

semicircular ends

43 and 44 joined together at the top and bottoms thereof by substantially straight

flat surfaces

45 and 46. An opening 47 is provided in the side 35 of the arm member 15 to intersect into the end 43 of the slot 42 while a smaller opening 49 is formed through the side 50 of the arm member 15 to intersect with the end 44 of the slot 42, the opening 49 being coaxial with the opening 47.

An adjusting screw 51 having a threaded portion 52 and opposed

cylindrical portions

53 and 54 to respectively be received in and mate with the

openings

49 and 47 of the arm member 15 in the manner illustrated in FIG. 3 has the threaded portion 52 thereof disposed within the slot 42 and is rotatable therein because an enlarged head 55 of the adjusting screw 51 abuts against the side 35 of the arm construction 15 while a retaining washer 56 carried in a slot means 57 at the end 53 of the adjusting screw 51 bears against the side 50 of the arm construction 15. In this manner, rotation of the adjusting screw 51 will not cause axial movement of the adjusting screw 51 relative to the arm construction 15.

However, a substantially cylindrical adjusting member 58 is provided and has a transverse threaded bore 59 passing therethrough and threadedly receiving the threaded part 52 of the adjusting screw 51 therein with the configuration of the adjusting member 58 being such that the same is threadedly received between the

opposed surfaces

45 and 46 of the slot 42 to permit the adjusting member 58 to be moved back and forth in the slot 42 between the

opposed ends

43 and 44 thereof. The forward portion 60 of the adjusting member 58 is adapted to be received in the opening 39 between the

legs

37 and 38 of the upper arm part or member 16 as illustrated in FIG. 2.

Since there would normally be play between the adjusting member 58 and the

legs

37 and 38 of the arm member 16 during the pivotal adjustment of the arm member 16 relative to the arm member 15 upon rotation of the adjusting screw 51, a cylindrical nonthreaded bore 61 is provided transversely through the adjusting member 58 parallel to the axis of the adjusting screw 51 to press fittingly receive a plastic rod 62 having opposed ends 63' and 64 adapted to be respectively wedged against the

surfaces

40 and 41 of.the

legs

37 and 38 of the arm member 16 to not only tend to eliminate any play between the arm member 16 and the adjusting member 58, but-.also to slide-against the-

surfaces

40 and 41 during an adjusting operation and to, absorb any shocks being imposed againstthe roller 28 so that such shocks willjnot be transferred to the adjusting member 58 and the threaded connection thereof with the adjusting screw 51 to damage the threads thereof.

In this manner, the threads on the adjusting member 51 and the threads in the opening 59 of the adjusting member 58 can be of micrometer accuracy so that very accurate adjustment of the arm member 16 relative to the arm member 15 can take place whereby the control device 10 will be properly operated at the proper time by a moving part of anapparatus or the like.

similar plastic material.

Thus, with the rod 62 being under compression between the

surfaces

40 and 41 of the

legs

37 and 38 of the arm member 16 and being fixed from sliding movement in the bore 61, the rod 62 is in wedged relationship to operatively interconnect the arm member 16 to the adjusting member 58 without any play therebetween as illustrated in FIGS. 5 and 6.

In particular, when it is desired to adjust the position of the arm member 16 relative to the arm member 15, the operator loosens the fastening member 17 and rotates the adjusting screw 51 at the bifurcated end 55 thereof whereby the adjusting member 58 will be axially moved in the slot 42 and through the plastic rod 62 will cause the lower end 36 of the arm 16 to pivot about the fulcrum or pivot means 17 whereby the roller 28 can be properly positioned for a desired operat- If desired, the plastic rod 62 canbe formed of nylon or a ing condition. At this time, the fastening member 17 is again tightened so that further rotational movement between the arm member 16 and the stationary member 15 cannot take place.

Therefore, it can be seen that this invention provides an adjustable actuator arm construction for the limit switch device 11 wherein the upper part or arm member 16 is adjustable to precise positions with the assembly of the arm construction 14 being simple, accurate and combined with rugged and robust resistance against any type of actuation whereby only two adjustments are needed to arrange for the arm member 16 to be in the desired position relative to the device 1 1.

Thus, not only does this invention provide an improved adjustable arm construction, but also this invention provides an improved control device utilizing such an arm construction or the like.

While the form of the invention now preferred has been described as required by the statutes, other forms may be used all coming within the scope of the claims which follow.

What is claimed is:

1. An adjustable actuator arm construction comprising a first arm member to be secured to a device that is to be controlled by said arm construction, a second arm member pivotally mounted to said first arm member and having an opening defining opposed spaced surface means, said first arm member rotatably carrying a threaded adjusting screw, and an adjusting member threaded on said adjusting screw, said adjusting member being operatively associated with said opposed surface means of said second arm member to pivot said second arm member relative to said first arm member in relation to the axial position of said adjusting member on said adjusting screw, said adjusting member having means wedged between said opposed surface means of said second arm member in all adjusted positions thereof.

2. An adjustable actuator arm construction as set forth in claim 1 wherein said first arm member has a slot therein receiving said adjusting member whereby said slot limits axial movement of said adjusting member relative to said adjusting screw. I

3. An adjustable actuator arm construction as set forth in claim 1 wherein said opposed surface means of said second arm member are defined by a bifurcated end of said second ar-m member withsaid opening being the space between such forked end.

4. An adjustable actuator arm construction as set forth in claim 1 wherein said means of said adjusting member wedged between said surface means of said second arm member comprises a rod carried by said adjusting member and having opposed ends respectively abutting said opposed surface means.

5. An adjustable actuator arm construction as set forth in claim 4 wherein said rod is formed of plastic material that facilitates sliding movement between said ends thereof and said surface means.

6. An adjustable actuator arm construction as set forth in claim 4 wherein-said adjustable member comprises a cylindrical part having a threaded bore passing diametrically therethrough and threadably receiving said adjusting screw.

7. An adjustable actuator arm construction as set forth in claim 6 wherein said cylindrical part has a nonthreaded bore passing therethrough in parallel relation to said adjusting screw and receiving said rod therein whereby the opposed ends of said rod project from opposite sides of said cylindrical part into engagement with said opposed surface means.

8. An adjustable actuator arm construction as set forth in claim 7 wherein said rod is fixed from sliding movement in its nonthreaded bore and is placed under compression between its opposed ends by being wedged between said opposed surface means.

9. An adjustable actuator arm construction as set forth in claim 1 wherein said second arm rotatably carries a roller thereon.

10. An adjustable actuator arm construction as set forth in claim 1 wherein a fastening member is carried by said arm members to respectively pivot said second arm member to said first arm member during an adjustment therebetween and to fasten said arm members together after the same have been adjusted by said adjusting screw.

1 1 In combination, a device having a rotatable control shaft and an adjustable actuator arm construction for rotating said shaft, said arm construction comprising a first arm member secured to said shaft of said device, a second arm member pivotally mounted to said first arm member and having an opening defining opposed spaced surface means, said first arm member rotatably carrying a threaded adjusting screw, an adjusting member threaded on said adjusting screw, said adjusting member being operatively associated with said opposed surface means of said second arm member to pivot said second arm member relative to said first arm member in relation to the axial position of said adjusting member on said adjusting screw, said adjusting member having means wedged between said opposed surface means of said second arm.

member in all adjusted positions thereof, and means securing said arm members together in an adjusted pivoted position thereof.

12. A combination as set forth in claim 11 wherein said first arm member has a slot therein receiving said adjusting member whereby said slot limits axial movement of said adjusting member relative to said adjusting screw.

13. A combination as set forth in claim 11 wherein said opposed surface means of said second arm member are defined by a bifurcated end of said second arm member with said opening being the space between such forked end.

14. A combination as set forth in claim 11 wherein said means of said adjusting member wedged between said surface means of said second arm member comprises a rod carried by said adjusting member and having opposed ends respectively abutting said opposed surface means.

15. A combination as set forth in claim 14 wherein said rod is formed of plastic material that facilitates sliding movement between said ends thereof and said surface means.

16. A combination as set forth in claim 14 wherein said adjustable member comprises a cylindrical part having a threaded bore passing diametrically therethrough and threadably receiving said adjusting screw.

17. A combination as set forth in claim 16 wherein said cylindrical part has a nonthreaded bore passing therethrough in parallel relation to said adjusting screw and receiving said rod therein whereby the opposed ends of said rod project from opposite sides of said cylindrical part into engagement with said opposed surface means.

1& A combination as set forth in claim 17 wherein said rod is fixed from sliding movement in its nonthreaded bore and is placed under compression between its opposed ends by being wedged between said opposed surface means.

19. A combination as set forth in claim 11 wherein said second arm rotatably carries a roller thereon.

' 20. A combination as set forth in claim 11 wherein a fastening member is carried by said arm members to respectively pivot said second arm member to said first arm member during an adjustment therebetween and to fasten said arm members together after the same have been adjusted by said adjusting screw whereby said fastening member comprises said means for securing said arm members together.

Claims

2. An adjustable actuator arm construction as set forth in claim 1 wherein said first arm member has a slot therein receiving said adjusting member whereby said slot limits axial movement of said adjusting member relative to said adjusting screw.

3. An adjustable actuator arm construction as set forth in claim 1 wherein sAid opposed surface means of said second arm member are defined by a bifurcated end of said second arm member with said opening being the space between such forked end.

6. An adjustable actuator arm construction as set forth in claim 4 wherein said adjustable member comprises a cylindrical part having a threaded bore passing diametrically therethrough and threadably receiving said adjusting screw.

11. In combination, a device having a rotatable control shaft and an adjustable actuator arm construction for rotating said shaft, said arm construction comprising a first arm member secured to said shaft of said device, a second arm member pivotally mounted to said first arm member and having an opening defining opposed spaced surface means, said first arm member rotatably carrying a threaded adjusting screw, an adjusting member threaded on said adjusting screw, said adjusting member being operatively associated with said opposed surface means of said second arm member to pivot said second arm member relative to said first arm member in relation to the axial position of said adjusting member on said adjusting screw, said adjusting member having means wedged between said opposed surface means of said second arm member in all adjusted positions thereof, and means securing said arm members together in an adjusted pivoted position thereof.

18. A combination as set forth in claim 17 wherein said rod is fixed from sliding movement in its nonthreaded bore and is placed under compression between its opposed ends by being wedged between said opposed surface means.

20. A combination as set forth in claim 11 wherein a fastening member is carried by said arm members to respectively pivot said second arm member to said first arm member during an adjustment therebetween and to fasten said arm members together after the same have been adjusted by said adjusting screw whereby said fastening member comprises said means for securing said arm members together.