US3612800A

US3612800A - Switch with adjustable switch actuator

Info

Publication number: US3612800A
Application number: US31504A
Authority: US
Inventors: Robert E Slopa
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-04-24
Filing date: 1970-04-24
Publication date: 1971-10-12
Anticipated expiration: 1988-10-12
Also published as: GB1295213A; FR2090635A5; DE2119824A1; CA933556A

Abstract

A plurality of rotary cams are mounted on a rotatable shaft. The position of each cam relative to the shaft is selectively adjustable to the nearest 30* by means of a positioning pin engageable with any of 12 openings in the cam. A plurality of switches are mounted on a frame structure in spaced relation to their respective cams. A three-piece switch actuator is pivotally mounted on the frame adjacent the switch. A screw element of the actuator selectively adjusts a slidable element in a direction generally tangential to the cam to provide selective adjustment of actuation of the switch throughout about 30*. The mechanism is, therefore, completely adjustable throughout 360*.

Description

United States Patent Robert E. Slopa 4615 Dean St., Woodstock, Ill. 60098 [21] Appl. No. 31,504

[22] Filed Apr. 24, 1970 [45] Patented Oct. 12, 1971 [72] Inventor [54] SWITCH WITH ADJUSTABLE SWITCH ACTUATOR I5 Claims, 3 Drawing Figs.

US. Cl 200/153 T Primary ExaminerJ. R. Scott Attorney-McCanna, Morsbach, Pillote & Muir ABSTRACT: A plurality of rotary cams are mounted on a rotatable shaft. The position of each cam relative to the shaft is selectively adjustable to the nearest 30 by means of a positioning pin engageable with any of 12 openings in the cam. A plurality of switches are mounted on a frame structure in spaced relation to their respective carns. A three-piece switch actuator is pivotally mounted on the frame adjacent the switch. A screw element of the actuator selectively adjusts a slidable element in a direction generally tangential to the cam to provide selective adjustment of actuation of the switch throughout about 30. The mechanism is, therefore, completely adjustable throughout 360.

SWITCH WITH ADJUSTABLE SWITCH ACTUATOR BACKGROUND The invention pertains generally to switch mechanisms and more particularly to an improved adjustable switch mechanism of the cam-operated type.

The prior art discloses switches and a rotary cam assembly together with a cam-follower which actuates the switch in accordance with the particular contour characteristics of the cam. Means are often provided for adjusting the position of the switch or for variably positioning the cam so that its angular relationship can be preset to precisely time the actuation of the switch. Most of these are not readily adjustable under operating conditions, however, and the adjustment is often a trial and error procedure.

Another prior art mechanism is shown in U.S. Pat. No. 2,83l,076 issued Apr. 15, 1958 to F. H. I-Iofing. That patent discloses an arm which is adjustable as to height to vary the position of the cam-follower in one direction, and a bolt for adjusting the position of the cam-follower in the transverse direction. Thus two adjustments were frequently necessary to achieve fine adjustment of the position of the cam-follower relative to the cam. It is desirable to have an adjustable switch mechanism which includes a switch actuator member which is simply and readily adjustable under operating conditions.

SUMMARY The present invention relates to switch mechanisms and more particularly to an improved switch mechanism which is readily adjustable.

The principal object of the present invention is provide an adjustable switch mechanism which is quickly and easily ad justed.

Still another object of the present invention is to provide an adjustable, cam actuated switch mechanism which is infinitely adjustable throughout the 360 of rotation of the cam.

Another object of the invention is to provide an adjustable switch mechanism having an improved switch actuator member which is adjustable by a single operation.

Still another object is to provide a switch mechanism having a switch actuator member which extends generally tangential to the cam and which is adjustable in the tangential direction.

These, and other objects and advantages of the present invention, will become apparent as the same becomes better understood from the following detailed description when taken in conjunction with the accompanying drawings.

DRAWINGS I FIG. 1 is a top plan view of a preferred embodiment of the present invention;

F IG. 2 is a side elevation view of the embodiment of FIG. 1; and

FIG. 3 is a partial sectional view taken generally along line 3-3 of FIG. 1 and on an enlarged scale.

DESCRIPTION Reference is now made more particularly to the drawings which illustrate the best presently known mode of carrying out the invention and wherein similar reference characters indicate the same parts throughout the several views.

The mechanism includes one or more switches generally designated 10. While other types of switches may be utilized, the present embodiment illustrates electrical switches of the overcenter snap-action type, each having connection telminals 11 leading to various contacts within the switch. Each switch has a control element 12 which, when depressed, throws the switch and, in the present embodiment, is of the overtravel type. Such switches are conventional and one suitable switch is shown and described in U.S. Pat. No. 1,960,020. Such switches are quite reliable in use, however, the exact point of displacement of the control element 12 which throws the switch may vary from switch to switch. Thus it is not always possible to determine exactly where the switch will be thrown except under operating conditions.

As best shown in FIG. 1, each pair of switches is mounted upon a bracket 13 by means of bolts 14 which extend through openings in the switches and also through openings in the brackets 13. Bracket 13 forms a portion of a frame structure 19.

Frame structure 19 has a pair of upwardly extending arms 22 on which a camshaft 24 is rotatably mounted. Camshaft 24 is rotated by a centrally 'located gear 26 which is engaged with a pinion 28 (see FIG. 2). Pinion 28 is mounted on the end of a drive shaft 29 which serves to drive the camshaft 24. Camshaft 24 may be driven by any suitable means and is herein arranged so that one revolution of the cam shaft constitutes a cycle of operation for the mechanism controlled thereby. Mounted on the camshaft 24, at points spaced longitudinally thereof, are any desired number of cam supports, each of which comprises an abutment portion or block 31 and a pin or stud 32 (see FIG. 1). A plurality of cams 34 are each mounted adjacent one block 31. Each of the earns 34 is formed with an axial opening 35 of such diameter as to fit slidingly upon the cam shaft 24. Each cam also has a plurality of apertures 36 (see FIG. 3) for selectively receiving the studs 32. As shown, the apertures 36 are in a concentric series herein shown as 30 apart. The arrangement is such as to provide for mounting the cam in a selective angular position relative to the camshaft, and to prevent angular movement of the cam relative to the camshaft.

For restraining the cams 34 against axial movement upon the camshaft 24, a compression spring 39 is provided between each pair of cams 34 to resiliently urge the cams against their adjacent block 31. The cams 34 may be moved axial against the pressure of the springs 39 when it is desired to alter the angular position thereof. By utilizing the arrangement shown, a single spring 39 operates to hold two cams 34 in position.

Referring to FIG. 2, it can be seen that each arm 22 has a gap 41 extending from one edge thereof past the axis of the camshaft 24. A bolt 42 is provided for varying the width of the gap and thereby moving the axis of the camshaft 24 upwardly or downwardly. In this manner the mesh of the

gears

26 and 28 can be adjusted to remove any backlash.

A switch actuator member, generally designated 50, is provided for each cam and switch arrangement. Preferably, the switch actuator member is positioned generally tangential to the cam and is adjustable through at least 3 of operation of the cam so that the resulting apparatus is adjustable through the entire 360 rotation of the cam. In the embodiment illustrated, the switch actuator member 50 is conveniently mounted on brackets 13 by means of a fastener 52 (see FIG. 2). In the embodiment illustrated, the switch actuator member 50 includes a body element 54, an adjustable element 56, and a screw member 58.

Reference is now particularly made to FIG. 3 which best illustrates the switch actuator member 50. As shown, body element 54 is conveniently formed of a stamping and includes a longitudinal extending member 61 having a top end 62 and a bottom end 63. Preferably, the longitudinal extending member 61 is utilized for contacting the control element 12. Adjacent the top end 62 is a laterally extending portion 64 having an opening for the passage of the screw element 58. Also adjacent the top end 62 are a pair of rearwardly extending ears 65 having an opening therethrough to receive the fastener 52 for the pivotal mounting purpose. Adjacent the bottom end 63 are a pair of laterally extending side members 66 which combine with the longitudinal member 61 to provide a longitudinally extending groove in which the adjustable element 56 is disposed. A fastener 67 extends through the adjustable member 56 to slidably mount the adjustable element 56 on the body element 54. Fastener 67 and the aforementioned groove hold the adjustable element 56 against rotation when the screw element 58 is rotated as hereinafter described.

Adjustable element 56 is bifurcated to accommodate the aforementioned fastener 67. The bifurcation results in spaced legs 71 and, at the lower end of these legs is mounted a camfollower 72 which engages the cam 34. At the top end of the adjustable element 56 is a threaded opening 73 which receives and engages the screw element 58.

Screw element 58 includes a threaded shank portion 82 received in the threaded opening 73 of the adjustable element. The shank portion 82 passes through the aforementioned opening in the lateral extending portion 64 of the body element. An enlarged head portion 84 is preferably disposed beyond all other portions of the switch actuator 50 so that it can be readily grasped by the thumb and finger for manual adjustment. The screw element has a shoulder portion 86 which engages the upper side of the lateral extending portion 64 and a retainer 88 at the underside thereof. The retainer 88 is conveniently of the type known as a Weldron True Ace retainer. The shoulder 86 and the retainer 88 assure that the screw element 58 remains in position when it is rotated.

It is now deemed apparent that the switch actuator member 50 is pivotally mounted closely adjacent the control element 12 and extends generally tangential to the cam 34. It can also be seen that a single adjustment of the switch actuator member is provided and that this adjustment changes theeffective length of the member 50 in the tangential direction. In other words, the position of the cam-follower 72 is selectively adjustable and thereby changes the position where it is laterally displaced by the cam 34.

It is also deemed apparent that the present invention pro vides an improved switch mechanism which is fully adjustable through 360 and that the switch mechanism has an improved switch actuator member in which only a single adjustment is required to adjust the position of the cam-follower. The apparatus is constructed and arranged so that the adjustment of the head portion 84 can be easily achieved when the cam 34 is being rotated under operating conditions. It can also be seen that the relative positions of the

gears

26 and 28 can be easily changed to prevent any backlash and thereby aid in the accuracy of the switch mechanism.

While a preferred embodiment of the invention has herein been illustrated and described, this has been done by way of illustration and not limitation, and the invention should not be limited except as required by the scope of the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In an adjustable, cam-actuated switch mechanism including a switch having a control element and adapted to be operated by displacement of the control element, a shaft carrying a rotary cam, and a cam-follower supported in operative relation to the rotary cam, wherein the rotary cam is adapted upon rotation to provide lateral displacement of the cam-follower of magnitude suitable for operation of the control element; the improvement comprising: a switch actuator member positioned generally tangential to the cam and including first and second portions; means at the first portion for pivotally mounting the switch actuator member for movement in the lateral direction; the second portion carrying the cam-follower thereon; means for adjustably moving the second portion relative to the first portion in the generally tangential direction to change the position where the cam-follower is laterally displaced; and'means supporting the switch with its control element in position to be operated by pivotal movement of the switch actuator member.

2. A cam-actuated switch mechanism as set forth in claim 1 wherein the first portion is longitudinally extending in the generally tangential direction, and the second portion is slidably mounted on the first portion.

3. A cam-actuated switch mechanism as set forth in claim 2 wherein the means for adjustably moving the second portion is a screw element rotatably mounted on the first portion and threadedly engaged with the second portion to move the same relative tothe first portion as the screw element is rotated.

4.: A'cam-actuated switch mechanism as set forth in claim 3 wherein the second portion has opposite facing sides, and the first portion is shaped to engage the opposite facing sides to prevent rotation of the second portion when the screw element is rotated.

4. A cam-actuated switch mechanism as set forth in claim 3 wherein the first portion is pivotally mounted at the end thereof remote from the cam-follower, the switch control element engages the first portion between the pivotal mounting and the other end thereof, and the screw element extends past the remote end of the first portion and has an enlarged head portion adapted for manual adjustment.

6. A cam-actuated switch mechanism as set forth in claim 1 wherein the switch actuator member is arranged for adjustment of the cam-follower through a preselected angular portion of the rotation of the rotary cam, and wherein the rotary cam has a series of apertures formed therein each angularly spaced at the preselected angle; and including means selectively engageable with at least one of the apertures to adjust the angular position of the rotary cam relative to the cam-follower; whereby the mechanism is fully adjustable through 360".

7. A cam-actuated switch mechanism as set forth in claim 6 wherein the means selectively engageable with the apertures comprises a block fixed to the shaft, and a stud carried by the block; and including resilient means normally urging the cam against the block.

8. A cam-actuated switch mechanism as set forth in claim 7 including a second switch and a second switch actuator, and also including a second similarly arranged cam mounted on shaft for operating the second switch through the second switch actuator, and wherein the resilient means operates on both cams and urges them in opposite directions.

9. A cam-actuated switch mechanism as set forth in claim 1 including a first gear mounted on the shaft, a drive gear meshed with the first gear at one side to drive the same and thereby drive the shaft and cam, first and second spaced supports for rotatably supporting the shaft with the gears meshed, said supports extending toward the one side and having a gap extending from one edge thereof past the axis of the shaft, and means for varying the gap to move the axis of the shaft and thereby adjusting the mesh of the gears to remove backlash.

10. In an adjustable switch mechanism including a switch actuator, a switch having a control element and adapted to be operated by displacement of the control element, displacement means providing a displacement movement to the switch actuator to operate the control element, a frame supporting the displacement means for said movement, means mounting the switch on the frame in a fixed position spaced from the displacement means; characterized in that the switch actuator includes a longitudinally extending body portion having first and second ends; means at the first end for pivotally mounting the body portion in a position extending past the control element; a longitudinally extending adjustable element slidably received on the body element and having an end remote from the first end of the body element; contact means at the remote end of the adjustable element for contact by the displacement means to impart pivotal movement to the switch actuator; and means for selectively moving the adjustable element in the longitudinal direction to relocate the position of the remote end and thereby change the actuation of the switch.

11. Mechanism according to claim 10 wherein the last-mentioned means includes a screw element rotatably mounted on the body portion and operable to move the adjustable portion in said longitudinal direction.

12. Mechanism according to claim 11 in which the screw element has an enlarged head disposed beyond the body portion and readily accessible for adjustment during operation of mechanism.

13. A switch actuator for use with a switch and displacement means providing a displacement movement to the switch actuator to operate the switch, and including: a body element having a longitudinally extending portion with first and second ends; the body element having a lateral portion at the first end; means at the first end of the body element for swingably mounting the switch actuator for movement when the displacement means operates; a longitudinally extending adjustable element slidably received on the body element for movement in the longitudinal direction and having an end remote from the first end of the body element; contact means at the remote end of the adjustable element for contact by the displacement means to impart swinging movement to the switch actuator; the adjustable element having a threaded opening at the end opposite said remote end; and a screw element rotatably mounted on the lateral portion of the body element and having a threaded shank received in the threaded opening in the adjustable element; whereby operation of the screw ele- 2 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,612,800 Dated October 12, 1971 Invent0r(s) Robert E. Slopa It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 15, delete "Weldron 'True Ace'" and insert Waldes TRUARC" Column H, line H, the claim numbered "H" should be 5 Column line 29, after on" insert the Column A, line 68, after "of" insert the Signed and sealed this 6th day of February 1973.

(SEAL) Attest:

EDWARD M. FI,E'I(IHER,JR. ROBERT GOTTSCHALK Attcsting Officer Commissloner of Patents

Claims

1. In an adjustable, cam-actuated switch mechanism including a switch having a control element and adapted to be operated by displacement of the control element, a shaft carrying a rotary cam, and a cam-follower supported in operative relation to the rotary cam, wherein the rotary cam is adapted upon rotation to provide lateral displacement of the cam-follower of magnitude suitable for operation of the control element; the improvement comprising: a switch actuator member positioned generally tangential to the cam and including first and second portions; means at the first portion for pivotally mounting the switch actuator member for movement in the lateral direction; the second portion carrying the cam-follower thereon; means for adjustably moving the second portion relative to the first portion in the generally tangential direction to change the position where the cam-follower is laterally displaced; and means supporting the switch with its control element in position to be operated by pivotal movement of the switch actuator member.

3. A cam-actuated switch mechanism as set forth in claim 2 wherein the means for adjustably moving the second portion is a screw element rotatably mounted on the first portion and threadedly engaged with the second portion to move the same relative to the first portion as the screw element is rotated.

4. A cam-actuated switch mechanism as set forth in claim 3 wherein the second portion has opposite facing sides, and the first portion is shaped to engage the opposite facing sides to prevent rotation of the second portion when the screw element is rotated.

6. A cam-actuated switch mechanism as set forth in claim 1 wherein the switch actuator member is arranged for adjustment of the cam-follower through a preselected angular portion of the rotation of the rotary cam, and wherein the rotary cam has a series of apertures formed therein each angularly spaced at the preselected angle; and including means selectively engageable with at least one of the apertures to adjust the angular position of the rotary cam relative to the cam-follower; whereby the mechanism is fully adjustable through 360*.

13. A switch actuator for use with a switch and displacement means providing a displacement movement to the switch actuator to operate the switch, and including: a body element having a longitudinally extending portion with first and second ends; the body element having a lateral portion at the first end; means at the first end of the body element for swingably mounting the switch actuator for movement when the displacement means operates; a longitudinally extending adjustable element slidably received on the body element for movement in the longitudinal direction and having an end remote from the first end of the body element; contact means at the remote end of the adjustable element for contact by the displacement means to impart swinging movement to the switch actuator; the adjustable element having a threaded opening at the end opposite said remote end; and a screw element rotatably mounted on the lateral portion of the body element and having a threaded shank received in the threaded opening in the adjustable element; whereby operation of the screw element moves the adjustable element in the longitudinal direction to change the position of the contact means.

14. A switch actuator as set forth in claim 13 wherein the screw element extends beyond the lateral portion of the body element and has an enlarged head portion constructed and arranged to be grasped by the thumb and finger for manual adjustment.

15. A switch actuator as set forth in claim 13 including means for mounting the switch intermediate the ends of the body element to be actuated thereby when the switch actuator is swung.