US2454341A - Switch operating mechanism - Google Patents

Description

Nov. 23, 1948. p. REPKA SWITCH OPERATING HECWISI 2 Sheeta-Sheet 1 Filed Sept. 7, 1944 5 m u lllll' 00 z aw in W I 1" 6 m 4 a m 9 7 h z a. w w m {7 l L v Q 3 4 R 6 m m V N NOV. 1948- P. T. REPKA 2,454,341

SWITCH OPERATING MECHANISM Filed Sept. 7, 1944 2 Sheets-Sheet 2 mug/wal f t/Z \7 MMA ML MIL Pas ed Nov. 23. 1948 SWITCH OPERATING MECHANISM Paul T. Repka, Freeport, Ill., alsignor to First Industrial Corporation, Wilmington, Del., a

corporation of Delaware Application September '7, 1944, Serial No. 552,063

UNITED "STATES PATENT OFFICE between the structure on which the switch is mounted and the moving element whichoperates the switch may vary in new structures and later as a result of wear or strain may vary further from time to time. Accordingly, it is necessary in the design of such a switch that it be capable of some adjustment when placed in new assemblies and that it be capable of further adjustment from time to time during use; I have found from experience that where switches of this character are used in places where extensive vibration ocours, as in airplanes and in tanks, the abovementioned adjustments, if made with the aid of screws, nuts, etc., are apt to be unsatisfactory, as such devices are themselves frequently jarred loose by prolonged vibration.

Accordingly, I have in this invention provided means for adjusting an overtravel switch permitting it to be readily adjusted after installation and during use and avoiding the difficulties produced by loosened screws or nuts. 3

One of the objects of my invention is to provide adjustment means for overtravel switches which will be of the utmost simplicity in construction.

Another object of the invention is to provide means for adjustment of'an overtravel switch, not requiring the use of wrenches and requiring no more than such a simple tool as a screwdriver or other instrument suitable for bending a piece of metal.

Another object of the invention is to provide adjustment means in an overtravel switch which can easily be altered after the switch is installed and so designed that the adjustment feature willitself not get out of adjustment.

The foregoing and other objects and advantages of the invention will become apparent from .a perusal of the specification and drawings in which I have described and shown, in order to illustrate the nature of the invention, one embodiment thereof, which is at present a preferred form of construction.

Referring now to the drawing:

Fig. 1 is a side elevation of an overtravel switch having mounted thereon an actuator arm made in accordance with my invention.

Fig. 2 is a top plan view with a part thereof broken away showing the assembly appearing in Fig. 1.

Fig. 3 is a plan view of the restoring spring employed to keep the actuator arm elevated.

Fig. i is a vertical longitudinal sectional view of the actuator arm shown in Fig. 1.

Fig. 5 is an end view of the actuator arm assembly as viewed from the left from Fig. 4.

Fig. 6 is a longitudinal sectional view of the actuator arm showing one of the adjustment tabs slightly bent to change the adjustment of the switch. Here. the free position of the arm is not altered, but the bending of the tab, as

shown, downwardly will cause the switch to operate upon a lesser downward movement of the arm.

Fig. 7 is a longitudinal sectional view of the actuator arm showing both adjustment tabs, to be later described, in their normal position and, diagrammatically, a striker element in position to strike the roller on the actuator arm.

Fig. 8 is a sectional view of the actuator showing both adjustment tabs bent from their normal position causing the free position of the arm to be somewhat lower and the operating point for the witch to occur at a somewhat lower angular position of the arm than would be the case of the unadjusted device shown in Fig. 7. I

Fig. 9 shows no adjustment on the tab which controls the free position of the arm but it retains the same adjustment on the other tab as does Fig. 8. Fig. 10 is another longitudinal sectional view of the actuator arm showing the small tab bent downwardly as in Fig. 8 to lower the free posi- I tion of the arm and the other tab bent downwardly as in Fig. 6.

Referring further to the drawing, as this invention is not concerned with the construction of the contact mechanism itself in the switch. it is sufllcient here to show only the housing I and the reciprocable plunger 2 extending from the housing and which operates the switch mechanism contained within the housing, a suitable switch being one such as disclosed in U. S. Patent No. 1,960,020, to McGall.

To support the actuator arm I provide a U-shaped bracket generally indicated as l in which the arm is pivotally supported on the pintle 4 extending through the bracket. The bracket spans the housing of the switch and is secured thereto by bolts 3a, the bracket having a central top portion lb. A sleeve 5 surrounds the pintle and two depending ears on opposite sides of the arm such as the ear 6 engage the sleeve I. The arm consists of the channel shaped member I on which the aforesaid ears are formed and the bracket 0 secured by rivets 9 and It to attests the outer end thereof for-supporting: the roller In order to restore the arm l to its uppermost or tree position there is provided the spring it (Fig. 3) having loops i2a. wrapped around the sleeve ii, an intermediate portion i222 bearing against the top of the housing iand legs ilc bearing against the underside of the arm l.

When the arm is in its tree position it may either bump against the edge the bracket 8 as shown in Fig. '7 or its free position may be lowered somewhat by bending the tab it downwardly as shown in Figs. 8 and 10. Such an adjustment will lower the position of the roller relatively to the striking piece which is sym bolized by the element l6, and which of course may be any moving structural element intended to operate such a switch. The entire arm and supporting bracket are (made of sheet metal steel: so that the tab may be bent dorm to any desired positie on it with a screw small pair of pliers or by using some other similar instrument. The sheet metal employed is however oi such strength and rigidity that it does not flex or bend appreciably under the forces to which it is nomally subjected in use. Therefore, when such adjustment is made it cannot fall out oi adiustnent due to some oi the usual causes such as vibration as might happen ill adjustment involved the use oi a screw or nut.

For operating directly on the plunger 2 of the switch I provide a post it extending through a tab it, having on its lower end an enlarged portion or collar ll for retaining the spring it under com pression against the under side of the tab it. A small collar it at the upper end of the post prevents it from being disengaged from the tab it.

Referring to Fig. i, if the actuator arm be rotated downwardly by the action of an exterior force the tab it acting through the spring it against the collar it on the post it will depress the plunger 2. which itself is usually spring loaded, and thus actuates the switch at a preselected operating point in the travel of the a. Further downward travel of the actuator arm may occur but thereafter the plunger 2 may engage astop within the housing or the bottom end of the post it may strike the top oi the switch housing, but due to its spring mounting in the tab it the post will not oppose further downward movement of the arm, but will merely slide through the tab.

Upon upward release of the arm l the spring it will res-tore it to its free position and the lower end of the post will be disengaged from. the plunger 2.

It will now be apparent that while the tab ill may be bent to vary the free position of the arm and consequently the pretravel of the arm before th post engages the plunger and operates the switch, the tab it may be bent upwardly or downwardly to alter the particular angular position or operating point of the actuator arm at which operation of the plunger 2 will occur.

I! tab it be bent upwardly, as shown in Figs. 8 and 9. the post It will not move the plunger 2 a sufll-cient distance to operate it until the arm has been rotated downwardly a greater angle than 2 to its operating position upon less angularmovement of the arm l. Since this tab is likewise made of sheet metal it can be bent with a easy. and permanent adjustment without the use or special tools is a desirable objective in these devices.

As was stated above the present invention does not involve the contact mechanism operated by the plumber 2. The actuator arm shown in the drawing is arranged to apply the operating force to a plunger having only a short travel, as would be required in a snap switch of the character shown in said Mclilall patent, but may be used with switches whose oper'atirie plungers have more or less travel than McGalls plunger.

The construction and arrangement of parts herein shown and described is at present the preicrred form of this invention, but it should be understood that some modification in the parts and in the details of construction are contemplated.

and may be employed, without departing from the spirit and scope or the invention defined in the following claims.

Having shown and described my invention, I claim:

1. An over-travel actuator for a plunger operated electric switch comprising a bracket for attachment in a fixed position relative to the housinc oi the switch, an actuator arm pivotally sup ported on said bracket for rotation toward and away from the switch to operate the same, a. metal member carried by and integral with said arm shapedand positioned to be bendable with respect to said am, and means supported on said member for contacting the plunger to operate the switch. the bending of said member relatively to said arm being arranged to alter the angular position of the arm on its pivot at which the plunger is actuated.

2. An actuator for a plunger operated electric switch comprising a bracket for attachment in a fixed position relative to the housing of the switch, an actuator arm pivotally supported on said bracket, a metal member carried by and integral with said arm shaped and positioned to be bendable with respect to said arm, means supported on said member for contacting the plunger to operate the switch, the bending of said member relatively to said arm being arranged to alter the angular position of the arm on its pivot at which the plunger will be actuated, and a bendable metal tab disposed between said arm and a fixed portion of said bracket for regulatably establishing the at rest angular position or said arm.

3. An actuator for an electric switch having a reciprocable plunger for operating the contact mechanism thereof, comprising a bracket rigidly connectable with the switch in which said plunger is located, an operating arm pivotally mounted on said bracket, a member carried by said am and a post supported on' said member arranged to contact the end or said plunger, means for resiliently supporting said post on said member to permit the post to yield after contacting and operating said plunger, said member being bendable relatively to the arm in order to vary the eiiective force for operating the switch.

4. An .actuator for a plunger operated electric 1 said arm, and a spring loaded post yieldably supported on said second tab for contacting and operating said plunger, the second tab being bendable relatively to the arm to vary the angular position about the pivotal point of said arm where said post will operate said plunger.

5. An'actuator for a plunger operated electric switchcomprising an overtravel arm, means for pivotally supporting the arm on a fixed axis for rotation toward and away from the plunger, means on said arm to be contacted by an external force for rocking said arm on said switch, means carried by said arm for contacting the plunger to operate it, and a bendable metal tab on said am for supporting the last said means, said tab being bendable by manually applied force at the time of installation of the switch or actuator to adjust the angular position of the arm at which the plunger will be operated.

6. An actuator for a plunger operated electric switch comprising a generally U-shaped bracket secured to the housing of the switch, an overtravel operating arm pivot-ally supported within said U-shaped bracket at a fixed distance from the switch housing, a metal tab integral with said bracket and bendable for determining the at rest position of said arm and for varying it, plunger operating overtravel means carried by said arm for contacting the plunger oi the switch switch comprising an overtravel operating arm,

and means for supporting said plunger operating means on said arm, said supporting means including a cantileverly mounted metal element travel movement of the am after operation of V the switch, and means for supporting said plunger operating means on said arm including a member readily bendable upon installation by manually applied force for thereby selectively determining the angular position of the arm at which said plunger will be operated and the amountot overtravel 01'- said arm.

'8. An actuator for a plunger operated electric switch comprising a U-shaped bracket for attachment at a fixed position relatively to and spanning the switch housing, an actuator arm pivotally supported within said bracket, and overtravel means carried by the arm to contact and operate the plunger. said mean including an element bendable by manually applied force whose bending determines selectively the ang'ular position at which the arm operates theplunger, and a member yieldablymounted on said element to permit 6 further angular movement of the. arm beyond the position necessary to operate the plunger? 9. An overtravel actuator for a. plunger operated electric switch comprising an overtravel operating arm, andmeans for pivotally supporting one end of said arm at a fixed position with respect to the switch plungensaid means including a tab bendable for variably limiting the at rest position of said arm, a bendable tab integrally carried by said arm, a spring loaded post yieldably supported on said second tab for contacting and operating said plunger, the second tab bein bendable with respect to the arm to vary the angular position about the, pivot point of said arm where said post will operate said plunger, and spring means for urging the arm to the at rest position. t g

10. An actuator for a plunger operated electric switch comprising an operating arm, means for pivotally supporting said am at a fixed axis for rotation toward and away from the plunger between an at rest position and an overtravel position, spring loaded overtravel means on said I arm positioned to engage the'plunger at a preselected position after preliminary free movement thereof upon rotation of the arm toward the plunger to operate the latter yieldable to permit overtravel movement of the arm, a tab on the arm for carrying the overtravel means bendable by manual force to preselect the position of the arm at which the overtravel means engages the plunger, and a bendable tab between the arm and the bracket to preselect the at-rest position of the arm to thereby preselect the operating point of the arm relative to the plunger, and spring means for moving the arm to the at-rest position.

11. An actuator for a plunger operated switch comprising a U-shaped bracket spanning the switch and having the sides thereof attached to the opposite sides of the switch housing to support the center portion of the bracket in fixed spaced relation to the plunger and switch housin an actuator arm comprising a sheet metal strip pivoted between the sides of the bracket below, the center portion having a free end for rotation ,of the arm toward the plunger by an externally applied force, a tab on said arm defined by a U-shaped cut intermediate the sides of said arm above the plunger, a spring loaded overtravel means mounted on said tab for operating the plunger, yieldable for overtravel movement of the arm, the tab being bendable with respect to the arm by manually applied force to preselect the operating position of the arm, a tab integral with the central portion'of the bracket engageable by the arm and bendable by manually applied force to preselect the rest position of the arm, and

spring means disposed between the housing and the arm forurging the arm to the rest position.

, PAUL T. REPKA.

'nnrnna'uoas crran The following references are of-record in the- Number Name Date 847,555 Craft L Mar. 19, 1907 1,682,549 Billerbeck Aug. 28, 1928 1,869,646 Anderson Aug; 2, 1932 1,969,488 Wagar Aug. '1, 1934 2,146,146 Innis Feb. 7, 1939 2,185,683 Barrett et a1. Jan. 2, 1940 2,260,964 Wilms Oct. 28, 1941 2,338,365 Thor-p et a1. Jan. 4, 1944

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