US2752440A

US2752440A - Push-button operated devices

Info

Publication number: US2752440A
Application number: US343048A
Authority: US
Inventors: Clyde F Robbins
Original assignee: Cutler Hammer Inc
Current assignee: Cutler Hammer Inc
Priority date: 1953-03-18
Filing date: 1953-03-18
Publication date: 1956-06-26
Anticipated expiration: 1973-06-26

Description

June 26, 1956 c. F. ROBBINS 2,752,440

PUSH-BUTTON OPERATED DEVICES Filed March 18, 1953 2 Sheets-Sheet l June 26, 1956 c. F. ROBBINS 2,752,440

PUSH-BUTTON OPERATED DEVICES Filed March 18, 1953 2 Sheets-Sheet 2 I I 1 I7 I 1 I I I I l. I I6 III I PUSH-BUTTON OPERATED DEVICES Clyde F. Robbins, Milwaukee, Wis., assignor to Cutler- Harnrner, Inc., Milwaukee, Wis., a corporation of Delaware Application March 18, 1953, Serial No. 343,048

11 Claims. (Cl. 20044) This invention relates to improvements in push-button operated devices and more particularly to push-button switch control stations of the type capable of being padlocked in a given position.

The primary object of this invention is to provide for a push-button switch a novel and simple latching means for latching of the push-button in any one of a number of different positions selectively.

Another object is to provide latching means of the aforementioned character which is adaptable to one-hole mounted push-button stations.

Another object is to provide latching means of the aforementioned character including a part located with a recess in one of the switch parts so as to be virtually unnoticeable and nonobst'ructive during operation of the switch.

Another object is to provide latching means of the aforementioned character which automatically remains in either the latched or unlatched position, as desired.

A more specific object is to provide a switch latching means employing an over-center C-spring which is virtually concealed within certain of the switch parts.

Another specific object is to provide a switch latching means of the aforementioned character which is capable of receiving a padlock hasp for locking the switch in a given position.

The novel features which I consider characteristic of my invention are set forth with particularity in the appended claims. The device itself, however, both as to its organization and mode of operation, together with additional objects and advantages thereof, will best be understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which,

Fig. l is an enlarged top plan view of a push-button switch station employing the subject invention and showing the push-button padlocked in its downward position;

Fig. 2 is a substantially full size sectional view showing the pushbutton padlocked in its upward position and having a portion of the switch housing broken away to show the stationary contacts and the bridging member; said sectional view being taken along the center line 22 of Fig. 1;

Fig. 3 is a sectional view taken along the horizontal line 33 of Fig. 2 showing the push-button in substantially full size and in its unlatched position;

Fig. 4 is a sectional view of a switch having modified mounting means and showing the push-button in its latched position; and

Fig. 5 is a sectional view of a switch having another modified mounting means and showing the push-button in its latched position.

Like reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to the drawings, they show a one-hole mounted push-button station positioned on a mounting panel 1 and provided with latching means to be hereinafter described. As shown in Fig. 2, the switch comnited States Patent Q 2,752,446 Patented June 26, 1956 prises

stationary contact sets

2 and 3 and lower and upper bridging members 4. Said

stationary contact sets

2 and 3 are adapted to be connected to electrical circuits to be controlled as by means of suitable terminal members (not shown), whereas the bridging members 4 are attached to a switch operating plunger 5. Said bridging members 4 are attached to plunger 5 by suitable spring means 6, so that the plunger 5 can be continued downwardly following initial contact of lower bridging member 4 with stationary contact set 2, thereby permitting continued movement of plunger 5 without changing the relative position of said lower bridging member 4 and said set 2.

Said plunger 5 is also biased upwardly by means (not shown) independent of the previously mentioned spring 6, so that it will automatically return to its upward position, shown in Fig. 2, when unlatched and released by the operator. Switch housing 7, which encloses the switch parts, is fastened as by means of bolts 8 to an adapter 9. Said adapter 9 is provided so that said switch housing 7 can be easily mounted within a single hole 1 in a suitable mounting panel 1.

Said adapter is provided with threaded openings for receiving said bolts 8 to thereby provide a rigid attachment between switch housing 7 and adapter 9. Said adapter 9 is also provided with a centrally disposed threaded opening 9 of a diameter slightly smaller than the opening 1 in panel 1. As shown in Fig. 2 said threaded opening 9 of adapter 9 is engaged by a threaded reduced end portion 10 of a bushing 11). Said bushing 10 is also formed with an enlarged end portion 16 and an opening 10 extending throughout its entire length. Between the reduced end portion 14 and the enlarged end portion 119 is an annular shoulder 10 Also in engagement with said reduced end portion 10* is a mounting nut 11 having a threaded opening 11 and formed with an annular shoulder 11'. Bushing 10 and mounting nut 11 are each formed with knurling at 10 and 11, respectively, to facilitate manual assembly and adjustment of said threaded members.

Positioned between mounting nut 11 and panel 1 is a positioning plate 12 formed with a downwardly extending tongue portion 12 and, as shown in Fig. 1, said tongue portion 12 of plate 12 extends into a small opening 1 in panel 1. Positioned between panel 1 and adapter 9 is a gasket 13 having therein a substantially centrally disposed opening 13 Said gasket 13 is so positioned on adapter 9 with respect to the annular shoulder 9* (Fig. 2) as to prevent contact between said gasket 13 and the threaded reduced end portion 10 of bushing 10 and consequent excessive wearing of the former. Said annular shoulder 9* also prevents excessive compression of said gasket 13 while providing for firm mounting of the switch regardless of whether or not a gasket is utilized. Said gasket 13 is also provided with a small opening for receiving tongue portion 12 of plate 12 and provides the desirable resiliency for firmly fastening the switch to the panel. it also provides an oil-tight seal for protecting the switch parts against the detrimental effects of oil. Adapter 9 is also formed with a small opening or recess (not shown) for receiving tongue portion 12 of plate 12 and is thereby prevented from rotating relative to panel 1 when said parts are in assembled position.

Slidably movable within opening 10 of bushing 11) is the plunger 5 having its upper end shaped to provide a manually operable push-button. As is believed apparent. the downward movement of plunger 5 will effect engagement between stationary contact set 2 and the lower bridging member 4, while release of said plunger will effect disengagement of set 2 and engagement of said upper bridging member 4 with contact set 3.

Under certain circumstances it becomes very desirable, if not essential, to insure against operation of the switch after the latter has been operated to a particular position. That is, such an arrangement is desirable to provide a safe place for maintenance personnel to work on machines controlled by the particular switch or to prevent interruption of a necessarily continuous operation. Toward such end this invention provides means for latching the plunger in a given position or, further, providing for padlocking thereof in any such given position.

As shown in the drawings, the latching-locking feature comprises a latching member 14 formed with a tongue portion 14 a main body portion 14 and an upturned portion 14. The main body portion 14 of latch member 14 is pivotally positioned in a slot 1i) in bushing 10 (see Fig. 2). Such pivotal positioning is elfected by means of a pin 15 which is press fitted into suitable openings in bushing 10 but which loosely and pivotally engages said main body portion 14. As shown in the drawings, the tongue portion 14 main body portion 14 and the upturned portion 14 are shaped .in accordance with the curvature of bushing 10. That is, the upturned portion 14 is shaped so as to lie closely against the knurled portion 10 of bushing 10 when in an unlatched position. Tongue portion 14 and main body portion 14' are shaped to permit unobstructed movement of plunger when latching member 14 is in its unlatched position.

As shown in Fig. 1, tongue portion 14 is adapted to engage the upper portion of plunger 5 to maintain the plunger in its downward position. Plunger 5 is also formed with an annular groove 5 to receive said tongue portion 14 and thereby maintain said plunger in its upward position, as shown in Fig. 2; or in any predetermined intermediate position, depending upon the location of said groove 5 with respect to the upper end of plunger 5. Also it is believed to be apparent that groove 5 might alternatively be formed to any desired width, thereby permitting limited movement of plunger 5 and providing operation of a given set of contacts while keeping the other set of contacts in a predetermined opened or closed position throughout such limited operation of plunger 5. It is thus possible to modify existing switches as desired to obtain any one of several types of switch operations.

Bushing is also provided with an annular groove 10 as shown in the drawings. Positioned within said annular groove is a C-spring 16 as shown in Fig. I. Said bushing 10 is also provided with a radial opening 10 which communicates with said annular groove 10 as shown in Fig. I. Said radial opening 19 receives and positions one end of said C-spring 16 while the other end thereof engages main body portion 14 of latching member 14. The portion of spring 16 intermediate its ends is positioned more or less within the annular groove 10* of bushing 10. The above-mentioned engagement be tween spring 16 and latching member 14 provides an over-center spring arrangement whereby said C-spring 16 maintains said latching member 14 in its latched or unlatched position as desired. Said latching member 14 is maintained by spring 15 in its unlatched position by virtue of abutting contact between the end of main body portion 14 and bushing 10 or by contact between the upturned portion 14 of latching member 14 and the knurled portion 10 of bushing 10. Said latching member 14 is maintained by spring 16 in its latched position by virtue of contact between the end of upturned portion 14 and said knurled portion 10 of bushing 10, as shown in Fig. 1.

As shown in Fig. 3 the ends of spring 16 are arranged to provide a force toward each other along lineX-X when latching member 14 is in its unlatched position. I This force along line XX will. maintain said latching member 14 in such unlatched position due to the rotational effect thereof on said member 14. When member 14 is opened or placed in its latched position, such direction of the force of spring 16 coincides wtih line YY in Fig. 1. Thus the rotational force of spring 16 as applied to member 14 will be shifted to the other side of pin 15 thereby maintaining said latching member 14 in its latched position. Therefore said latching member 14 will remain in either its unlatching or latching position due to the force of said C-spring irrespective of whether or not plunger 14 exerts a force on tongue portion 14 of latching member 14. As will be understood, the hasp of an ordinary padlock may be inserted into and locked in the opening in the upturned portion 14 of latching member 14 to prevent movement of the plunger 5 in an upward direction (in Fig. l) or in either direction (in Fig. 2).

The modification shown in Fig. 4 employs the above explained latching-locking feature mounted in bushing 17 .in a manner also heretofore explained. The primary purpose of this modification is to provide a sleeve member 18 of such length as to prevent the plunger 5 from extending beyond the end thereof to thereby render the same less susceptible to accidental or nnintential switch operation.

As shown, sleeve 18 is formed with external threads for threadedly receiving said bushing 17. A mounting nut 19 formed with an internal thread for engagement with the external threads on said bushing 17 is provided to rigidly secure the switch to the mounting panel 1. The lower peripheral edge of said sleeve 18 is flanged as at 18 Positioned between said flange 18 and the mounting panel 1, is a resilient gasket 13. Positioning plate 12 is inserted between said mounting plate and the mounting nut 19.

In order to permit positioning of the latching-locking feature at various desirable positions around said plunger 5, said sleeve 18 is formed with several slots 18, for slidably receiving the tongue portion 14 latching member 14. Such engagement between tongue portion 14 and a slot 18 provides a tamper-proof arrangement while padlocked in such position. That is, such engagement would prevent substantial relative movement between bushing 17 and sleeve 18 thereby insuring against removal of the latching-locking feature without first removing the padlock.

The modification of Fig. 5 shows a means for providing an ordinary switch with a bushing 20 constructed with the novel latching-locking feature of the present invention. In this arrangement the bushing 20 threadedly engages sleeve 21 thereby serving the dual purpose of rigidly holding the switch structure to the amounting panel 1 and also carrying the locking member 14. As will be understood, the bushing 20 is not inherently susceptible of being positioned for the convenience of operating latch- .ing member 14, but must necessarily be positioned so as to effect secure mounting of the switch. A certain amount of flexibility can be attained by varying the thickness of gasket 13 or by employing several gaskets as shims as shown in Fig. 5.

It will be apparent that this latching-locking means can be applied to and successfully used with any plunger operated mechanism. More specifically, it is realized that this invention can be used in conjunction with any desired switch arrangement; that is, any number of n0rmally open contacts and/or any number of normally closed contacts with latching and locking ability in any desired position.

Although I have shown and described certain specific embodiments of my invention, I am fully aware that many modifications thereof are possible. My invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the appended claims.

I claim:

1. The combination with a device having an operating pushdiutton, of a latching member pivotally positioned relative to said push-button and capable of engaging said button to positively prevent movement thereof from a given normal operative position thereof or alternatively engaging said button to retain the same in a different position, and over-center C-spring means in engagement with said latching member to maintain said latching member engaged with or disengaged from said button as desired.

2. The combination with a device having an operating push-button, of a latching member pivotally positioned relative to said push-button and capable of engaging said button to positively prevent movement thereof from a given normal operative position thereof or alternatively engaging said button to retain the same in a diiferent position, and over-center C-spring means in engagement with said latching member to bias said member in either pivotal direction selectively, thereby biasing said member into or out of controlling engagement with said button as desired.

3. The combination with a device having an operating push-button, of a latching member pivotally positioned relative to said push-button and capable of engaging said button to prevent movement thereof, and a C-spring anchored at one end and in engagement with said latching member at its other end to bias said member in either pivotal direction selectively, thereby biasing said member into or out of engagement with said button as desired.

4. The combination with a device having an operating push-button, of a latching member pivotally positioned relative to said push-button and capable of engaging said button to prevent movement thereof, over-center C-spring means in engagement with said latching member to maintain said latching member engaged with or disengaged from said button as desired, and means on said latching member for receiving a padlock hasp to prevent disengagement of said latching member from said button.

5. The combination with a device having an operating push-button, of a bushing formed with an opening for slidably receiving said push-button, a manually operated latching member pivotally positioned on said bushing and adapted for pivotal movement into engagement with said button to thereby prevent movement of the latter, and C-spring means having opposite ends thereof respectively engaged with said latching member and said bushing to thereby bias said latching member in either pivotal direction selectively, to thereby bias said member into or out of engagement with said button as desired.

6. The combination with a device having an operating push-button, of a bushing formed with an opening for slidably receiving said push-button, a latching member pivotally positioned on said bushing and capable of engaging said button when pivoted to thereby prevent movement thereof, and spring means at least partially recessed within said bushing and in engagement with said latching member and said bushing to bias said member in either pivotal direction selectively, to thereby bias said member into or out of engagement with said button as desired.

7. The combination with a device having an operating push-button, of a bushing formed with an opening for receiving said push-button and formed with an annular groove, a latching member pivotally positioned on said bushing and capable when pivoted of engaging said button to thereby prevent movement of the latter, and a C-spring at least partially recessed within said annular groove and engaging said member and said bushing to bias said member in either pivotal direction selectively.

8. The combination with a device having an operating push-button, of a bushing formed with an opening for receiving said push-button and formed with an annular groove, a latching member pivotally positioned on said bushing and capable when pivoted of engaging said button to thereby prevent movement of the latter, a C-spring at least partially recessed within said annular groove and engaging said member and said bushing to bias said member in either pivotal direction selectively, and means on said latching member for receiving a padlock hasp to prevent disengagement of said latching member from said button.

9. The combination with a device having an operating push-button, of a bushing formed with an opening for receiving said push-button and formed with an annular groove, a latching member pivotally positioned on said bushing and capable when pivoted of engaging said button to thereby prevent movement thereof, a C-spring at least partially recessed within said annular groove and engaging said member and said bushing to bias said member in either pivotal direction selectively, and means on said latching member for receiving a padlock hasp to prevent disengagement of said latching member from said button, said last mentioned means having a shape corresponding to at least a portion of the contour of said bushing and being juxaposed with respect thereto when disengaged from said push-button.

10. In combination, an electric switch having an operating push-button movable rectilinearly, means to make and break an electric circuit to be controlled, said means being operated by said push-button to make and break said circuit selectively, a bushing formed with an opening for receiving said push-button and formed with an annular groove, a latching member pivotally positioned on said bushing and capable when pivotally moved of engaging said button to thereby prevent movement of the latter, a C-spring at least partially recessed within said annular groove and engaging said member and said bushing to bias said member in either pivotal direction selectively, and means on said latching member for receiving a padlock hasp to prevent disengagement of said latching member from said button.

11. In a one-hole mountable push-button switch station, an electric switch having an operating push-button movable rectilinearly, means to make and break an elec tric circuit to be controlled, said means being operated by said push-button to make and break said circuit selectively, a bushing formed with an opening for slidably receiving said push-button and also formed with a slot and an annular groove, a latching member pivotally positioned within said slot and capable when pivotally moved of engaging said push-button to thereby prevent movement of the latter, a C-spring at least partially recessed within said annular groove and engaging said member and said bushing to bias said member in either pivotal direction selectively, means on said latching member including an opening for receiving a padlock hasp to prevent disengagement of said latching member from said button, said last mentioned means having a shape corresponding to at least a portion of the contour of said bushing and being juxtaposed with respect thereto when disengaged from said push-button, and means for mounting said station in one hole of a mounting panel, said last mentioned means including a positioning plate for preventing relative movement between said switch and said mounting panel.

References Cited in the file of this patent UNITED STATES PATENTS 1,285,093 Fishel Nov. 19, 1918 2,370,877 Robbins Mar. 6, 1945 2,659,780 Berger Nov. 17, 1953 2,673,259 Appleton et a1 Mar. 23, 1954