US2487725A - Switch - Google Patents

Description

Nov.. 8, 1949 E T. PLATZ 2,487,725

' SWITCH Filed Feb. ll, 1948 2 Sheets-Sheet l INVENTOR. WOOJ E. T. PLATZ Nov. 8, 1949 SWITCH 2 Sheets- Sheet 2 Filed Feb. 11. 1948 Patented Nov. 8, 1949 SWITCH Elwood T. Platz, Detroit, Mich.,

assignor to Bulldog Electric Products Company, Detroit, Mich., a corporation of West Virginia f Application February 11, 1948, Serial No. 7,600

f (ci. zoo-116) 4 Claims. l

This application relates to switches and more particularly tov manually operable switches having automatic overload release provisions.

My Patent No. 2,385,727 of September 25, 1945, discloses a switch which includes a contacter releasably held by a latch which is adapted to be released either manually or automatically, as on overloads.

In such switch parts are provided so that the co-engagement of an unlatching and relatching handle with a part of the casing deiines an extreme outer position of the handle to indicate that there had been an automatic unlatching as a cause for circuit opening. In addition parts yare provided so that the cri-engagement of the handle with a pawl defines an intermediate position of the handle to indicate that the parts are in closed circuit position. These are the only two rest positions of the handle in such switch.

It has been found desirable and a principal object of the present invention is to provide parts which indicate not only the fact of circuit opened condition, but also, as to the former, the cause for circuit opening, whether the circuit open condition be due to manual operation or be due to overload release operation.

Therefore it is an object of the present invention to provide in such a switch a pawl or the like for engaging a lug of the handle but only after and in response to an unlatching stroke of such handle to dene a position of the handle diiferent from those dened by the parts shown in my Patent 2,385,727 whereby to indicate that there had been a manual unlatching and thus indicate not only the fact of circuit opened condition but also the cause for circuit opening.

A further object is to obtain such a characteristic in a switch of such a character that all operations of the handle, at least from the point of view of the user, are substantially identical. With switches so constructed that substantially identical movements, so far as the operator is concerned, are required for closing the switch after a manual opening and for closing it after an automatic opening, it is quite a dirlicult problem to provide means to indicate not only the fact that the switch is open, but also to indicate which factor caused the switch to open, manual operation or automatic overload release operation. Therefore, another principal object of the present invention is to provide in a switch of a character that requires no substantially diierent movement of the handle for closing after manual opening than for closing after automatic opening, means to indicate not only that the circuit is open, but also the cause of opening, manual or automatic opening.

A switch constructed in accordance with the foregoing objects in mind has been disclosed in the appended drawings. In these drawings Fig. 1 shows a switch in perspective.

Fig. 2 is a section (as if on line 2 2 of Fig. 1), but showing the switch parts in their circuit closed position, and with the indicator, in this case a handle, in its lower-most position to indicate that the circuit is closed.

Fig. 3 is a view like Fig. 2 but showing the switch parts in open circuit position and with the indicator or handle in an intermediate position to indicate that circuit opening was caused manually,

Fig. 4 is a view like Fig. 3 showing the parts in circuit open position, but with the indicator or handle in an upper-most position to indicate that the circuit opening was caused by automatic overload release.

Fig. 5 is a section on line 5 5 of Fig. 4.

Fig. 6 is a diagram illustrating the cooperation of the switch casing, the indicator or handle, and a legend card mounted in the handle for indication purposes.

Fig. '7 shows an indicator return arrangement in detail. The drawings show the switch as comprising a cup shaped casing I0 having an open front closed by a plate or cover I I secured thereto by screws I2.

The back of the case is formed with a vent opening I3 and through the back project line and load terminals I4 and i5 respectively.

In an opening I6 reciprocates an indicating element having an exposed part providing a handle II formed as a push button. Within the casing is a handle return spring 3|, Fig. 7, which normally biases the handle outwardly. The handle is adapted to be pushed in for its useful functions, such. as circuit opening and relatching, and when released by the person operating the switch, the handle is returned-idly and automatically by the handle return spring 3l in an idle return stroke during which reclosing of the circuit is accomplished by parts described later, these operating without assistance from the released handle, whose outward movement, though simultaneous with circuit closing, is independent of the circuit closing operation, the latter being accomplished in a manner later to be described.

Outward movement of the handle is limited by the cooperationof handle lugs 34-I 34 and translator pawls 35--I35, respectively, Figs. 2-3. Still another limitation or stop for handle movement namely,

with pawl 35, and lug |34 with pawl |35, de-

termines outward travel of the handle but only during the closed circuit, on, Fig, 2, and the manually caused open circuit positions, oiI, Fig. 3, respectively, merely holding the handle in a full in or "on position, Fig. 2, and in an intermediate or oil position, Fig. 3 and preventing the handle from going all the way out to its tripped, Figs. 4-7, position. Lugs 36-31 define the full out or tripped position of the handle.

Handle position is relied upon to indicate `the position of the circuit closing parts within the casing, and also to indicate the cause of circuit opening. The handle is furthest out in the tripped position, held by lug 31, that is to say, the position when the circuit is open and opening has been caused by overload release. The handle is held by the pawl 35 in its full in or on position. The handle is held by the pawl |35 in an intermediate position to indicate the fact that the circuit is open and that opening has been caused by manual actuation.

Lugs 36 and 31 of the handle and casing cooperate to dene a full out or tripped position (Figs. 4 7) for the handle to indicate that circuit opening was caused by overload release.

Movement of the handle is utilized to operate an indicator in the form of a plate 36 having an .actuating lug 45 and having trip, 011, and off" markings. The plate is disposed within an undercut portion lll of the handle so that only one of the three markings of the plate is visible at any time through a window slot d? of the handle. The lug it rides in a camming groove 43 formed in the upper portion of the back of the casing.

As the handle moves up and down, the plate 38 moves Iback and forth alternately in the undercut 4| to expose its markings alternately to view through the slot 42. When the handle is full out or in the tripped position, the lug 40 of the indicator plate 38 is in the upper part of the groove 43 and the trip marking is exposed through slot 42. As the handle is moved down, plate 38 slides down with the handle and forward of the slot to present its on and off markings to slot 42. In the on" position of the handle, lug 40 of plate 38 is in that part of groove 43 which causes plate 38 to have its on marking exposed through slot 42. Only when the handle is in the extreme out or tripped position will the lug 40 be in the upper part of groove 43 so that the trip marking of plate 36 is exposed through slot 42.

The handle occupies but two circuit open positions. The handle has three rest positions, trip, on and oi, and these three positions indicate the condition of the circuit-controlling parts of the breaker and the cause of circuit opening.

These parts include a stationary contact 44,

, formed integral with line terminal I4, and positioned near a stop lug 41 of the casing. Adapted to makebutt contact with the stationary contact 44 is a movable L-shaped contactor 49 to which is riveted at 5| a bimetal strip or overload release means 52. Rivet 5| is formed as a pin to provide a loose pivotal connection between the contactor-overload release means assembly- 49-52, and a translator in the form of a plate 53 of insulation, the latter having an elongated back of the casing. Pawls 35 and |36 are integral parts of plate 53.

An operating spring 56 reacts against the lower surface of the casing and has its upper end entgaging a spring lug 56 formed from the contac- Springf56 functions to rotate the contactor-release means assembly counter-clockwise for circuit opening on the axis or pin 5| when the latch. I

that is the hook 60 forming the free end of the bimetal strip 52, is released from engagement from the latch holding abutment, the latching edge 6| of the plate 53.

Spring .56 also biases the contactor 43 and the plate 53 upwardly when the latch holds and thus providesa force to move the contactor towards and against the stationary contact 44 for circuit closing when the latch is relatched or holding.

Release of latch 60 from the holding means 6| is effected either automatically by the warping of the release means, the bimetal 52 on overload, or manually by the camming action provided by a manual release means in the form of a sloping cam 62 formed integral with the handle in the specii'lc embodiment shown, but adapted to be formed in any other suitable way so as to form an operative connection between the handle or indicating element vand the latch 50. When the manual release means or cam 52 is pushed down, as by pushing the handle down, it cams latch 65 off the abutment 6| to permit circuit opening movement of the parts, the contactor being rocked counter-clockwise relative to the plate 53 by the spring 55 for circuit opening.

In a circuit opening action spring 55 through pivot axis 5| will slide the plate 53 upwardly with the latter guided by the casing. The engagement of the lower edge of plate slot 54 with casing stop 55 will limit such movement of the plate. That stop 55 will at that time function as a pivot for the plate 53 and since the line of action of spring 55 through axis 5| is to the left of that pivot, plate 53 will rock clockwise about stop 55 under the spring biasing force. Pawl 35 of plate 53 which normally holds handle I1 at lug 34 against extreme outward movement, will In the on position, however, the plate 53 is so positioned by the spring 56 and by the casing walls that pawl' 35 engages handle lug 34 to hold the handle against outward travel. A exible connector 65 connects the bimetal strip to the load terminal 5 to complete the circuit.

To relatch the parts, after a circuit opening, handle I1 is pushed down to cause notch 1| to engage a resetting lug'12 of the plate 53 and to cause the pin 5| to slide downwardly. The part of plate 53 connecting relatching lug 12 and pin 5| acts as a translator. The contactor 43 will move downwardly with pin 5| until it reaches resetting stop 41 of the casing, if it has not already reached that stop. Continued downward movement of the handle, the lug 12, and the pin 5|, will cause the contactor to rock clock- `wise on axis 5I far enough to cause latch 60 l the handle by the operator at that time will permit the handle to return outwardly and idly vand at the same time will permit spring 56 to SlOt 54 receiving a Stop lug 55 formed on the 75 rock the contactor slightly counter-clockwise so that it will assume its final on position with latch 60 engaging abutment 6| and with the contacts engaged under pressure of spring 56 and plate 53 will have rocked counter-clockwise to remove its lug T2 out of the path of the relatching notch 1|.

Indication When the parts are in the on position oi' Fig. 2, the handle is held in its innermost position by the engagement of parts 34-35.

When the circuit opens due to an overload release, the translator 53 is rocked clockwise slightly to remove its pawl 35 from handle lug 34 so that handle return spring 3| can move the handle outwardly until handle lug 38 is engaged by casing lug 31, Fig. 7, which engagement terminates handle movement. In such clockwise movement of plate 53, its pawl |35 will not have moved into the path oi travel of handle lug |34 before that handle lug |34 has moved outwardly beyond pawl |35 and, consequently, pawl 35 will not in any way interfere with full outward travel of the handle.

However, when the circuit is opened due to a manual actuation, handle |1 will have traveled inwardly from the position of Fig. 2 suillcient to enable the latch release cam 62 to engage and release the latch 60, and plate 53 will have moved clockwise to present its pawl |35 into the path of travel of the handle lug |34. Because the handle was pushed inwardly into the casing a considerable extent, pawl 35 will be engaged by and will interfere with movement of handle lug |34 and will, thus, hold the handle by the engagement at |34-|35 in the intermediate position of Fig. 3, thus indicating that the circuit opening was due to a manual release, as' by pushing the handle inwardly from the position 0f Fig. 2.

There will be no cooperation between parts |34 and |35 unless the handle had been pushed inwardly prior to the movement of pawl |35 into the path of travel of lug |34. Thus, there is no cooperation between parts 34| 35 on overload release opening, and, thus, there is nothing to prevent the handle from moving all the way out to the position of Fig. 4 on an overload release opening. However, if the opening were caused by manual actuation, namely by pushing the handle inwardly, parts 34 and |35 will cooperate and will prevent the handle from moving outwardly to the position of Fig. 4, but instead will prevent the handle from moving outwardly beyond the position of Fig. 3. The difference in handle position evidenced by a comparison of handle position of Fig. 3 with that of Fig. 4, furnishes an indication as to the cause for latch release and the cause for circuit opening movement.

Now having described the switch or circuit breaker herein disclosed, reference should be had to the claims which follow for a determination of the invention.

I claim:

1. In a switch of the character comprising a stationary contact, a movable contactor for engaging it, latch means for the contactor, spring means for moving the unlatched contactor from the contact and for urging the latched contactor against the contact, a handle for engaging the latch directly and unlatching it so that the con- .tactor leaves the contact, the handle being movable for relatching the released latch so that the contactor returns to contact engaging position, there to be held by the spring, the handle being formed to have an advance stroke and a return stroke, two strokes in each cycle of movement, and so arranged with respect to the latch means and the contactor that in the normal operation of the handle it goes through a complete cycle for latch releasing and a complete cycle forv relatching and circuit closing, the handle being formed to be advanced manually and returned automatically unless held, a return spring for automatically returning the handle, a stop for limiting the outward movement ofthe handle caused by the return spring to an extreme position, a pawl for limiting outward movement of the handle, when it is engaged by the pawl to an intermediate position, the pawl being movable into and out of a handle stopping position, and means connecting the handle and the pawl whereby the pawl shifts from handle stopping position in response to advance of the handle from its intermediate position and shifts into handle stopping position in response to advance of the handle from its extreme position, .that improvement which consists of a second pawl in said switch and a stop lug on said handle, said second pawl and said stop lug being arranged to coengage but only in response to a manually caused, unlatching, stroke of said handle and arranged to define a position for said handle, different from that deiined by the interengagement of the rst mentioned pawl with the handle, whereby to indicate that the handle had been advanced manually to cause unlatching and thereby switch opening manually.

2. In a switch of the character comprising latch means, and a handle separate from the latch means for unlatching it, and spring means for moving the latch means well away from latching position when it is unlatched, the handle being operable for returning the latch means to the latching position after it is moved away therefrom by the spring, a pawl for engaging the handle to limit its movement, the handle, in its unlatching movement 'also releasing the pawl from it, and in its relatching movement resetting the pawl to handle motion limiting position, the pawl, when engaging the handle, defining an outward position of the handle intermediate its extreme outward and inward positions, that improvement which consists of a second pawl in said switch and a stop lug on said handle, said second pawl and said stop lug being arranged to coengage but only in response to a manually caused, unlatching, stroke of said handle and arranged to deilne a. position for said handle, different from that deilned by the interengagement of the rst mentioned pawl with the handle, whereby to indicate that the handle had been advanced manually to cause unlatching and thereby switch opening manually.

3. In a switch of the character comprising a contactor, automatically and manually releasable latch means therefor, automatic latch releasing means, spring means for moving the contactor from circuit closing position when it is unlatched, and a manually accessible and manually actuated means having a portion for releasing the latch means, and a translator for operatively connecting the latch means and the manual means but only when the latch means is unlatched, for enabling the manual means to relatch the latch means, the latch means and translator being interconnected so that unlatching positions the translator into a manual means engaging path, and relatching moves it out of that path, a pawl forming part of the translator for engaging the manually actuated means to limit its movement, the manually actuated means, in its, la.tch'releasing movement, also releasing the pawl-v from it, and in its relatching movement resetting the pawl to a position where it limits movement of the manually actuated means, that improvement Awhich consists of a second pawl on said translator, and a stop lug on said manually actuated means, said second pawl and said stop lug being arranged to coengage but only in response to a manually caused unlatching movement of said manually actuated means and arranged .to denne a position for said manually actuated means, different from that defined by the. interengagement of the irst mentioned pawl with' the manually actuated means, whereby to indicate that the manually actuated means had been moved manually to cause unlatching and thereby switch opening manually.

' a. In a. switch of the character comprising a manual means constructed and guided to have successive identical movements, automatically andmanually releasable latch means, automatic latchreleasing means, a cam forming an operative unlatching connection between the manual means andthe latch meansand a translator for forming anoperative relatching connection between the manual means and the latch means, the parts being so constructed that the translator is in a position to connect the manual means and latch means operatively, but only when the latch means is .-unlatched, being out of that position when the latch means is latched, the latch means and translator being so operatively connected that ,when the latch means is unlatched it moves the translator into manual means engaging position, andfvwhen'the latch means is moved to latch, it moves the` translator out of manual means en- 4gaging position, and when the translator is in manual means engaging position and is moved by the manual means, it translates manual means movement into relatching movement of the latch means, a pawl forming part of the translator for engaging the manual means to limit its movement, the manual means, in its unlatching movement, also releasing the pawl from it, and in its rel-etching movement resetting the pawl to a position where it limits movement of the manual means, the pawl and the manual means being so formed that the position in which the pawl holds the manual means is an intermediate position of the manual means, different from the position it occupies when the pawl does not hold the manual operable means, whereby manual means position indicates the position of the pawl, the translator, and the latch, that improvement which consists of a second pawl on said translator, and a stop lug on said manually actuated means, said second pawl and said stop lug being arranged to coengage but only in response to la manually caused unlatching movement of said manually actuated means and arranged to define a position for said manually actuated means, diierent from that defined by the interengagement of the rst mentioned pawl with the manually actuated means, whereby to indicate that the manually actuated means had been moved manually to cause unlatching and thereby switch opening manually.

ELWOOD T. PLATZ.

REFERENCES CITED The following references are of record in the iile 4o this patent:

UNITED STATES PATENTS Number Name Date 1,656,851 Anderson et al Jan. 17, 1928 2,013,827 Jennings Sept. 10, 1935 2,212,732 Fisher Aug. 27, 1940 2,231,072 Jackson Feb. 11, 1941 2,385,727 Platz Sept. 25, 1945

Images