US3015010A

US3015010A - Environment free switch

Info

Publication number: US3015010A
Application number: US855644A
Authority: US
Inventors: Orion S Greeson
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-11-27
Filing date: 1959-11-27
Publication date: 1961-12-26
Anticipated expiration: 1978-12-26

Description

Dec. 26, 1961 O. S. GREESON 3,015,010 ENVIRONMENT FREE SWITCH Filed Nov. 27, 1959 2 Sheets-Sheet 1 Orion 5. Greeson INVENTOR. BY yzwy 3m Dec. 26, 1961 o. s. GREESON 3,015,010

ENVIRONMENT FREE- SWITCH Filed Nov. 27, 1959 2 Sheets-Sheet 2 as 62 95? 90 I 88 54 a a2 60 42 Fig. 5

WW Em States This invention relates generally to switches and more particularly to a maintained-position switch which is hermetically seated within a housing so as to be absolutely isolated from environmental eifects.

It is the principal object of this invention to provide a novel switch construction which is stable in either of two positions and which may be switched from a first to a second position by merely depressing a switch actuator.

It is a further object of this invention to provide a novel switching assembly which is hermetically sealed within a housing so as to enable the switch assembly to be divorced from harmful environmental eifects. An elastic diaphragm is provided and comprises one wall of the housing enabling the switch actuator of the switch assembly to be depressed through the elastic diaphragm.

It is a still further object of this invention to provide a novel switch construction which is relatively simple and accordingly easy to operate and inexpensive to manufacture. Also, the simplicity of construction assures reliable and long-lasting operation.

In order to isolate the switch assembly from the harmful environmental elfects, the housing is hermetically sealed. The switch is thereby sealed against explosive laden atmosphere or vapors and accordingly is explosion proof. Further, the switch is sealed against water, oil corrosive fumes, vapors, dirt, and other things that might cause malfunctioning and a shortened life. The housing is constructed of metal which is preferably electrically grounded so as to reduce the danger of shock. All switch elements are constructed of metal except the insulation which is of an inorganic material such as glass, ceramic, or the like. Inorganic material is utilized inasmuch as it is Well-known that electrical contacts which are sealed within an atmosphere in cohabitation with organic material, are subject to vary rapid deterioration which would ultimately cause mal-functioning and short life. Inasmuch as the entire switch construction is of metal, glass, ceramic, or the like, the switch is substantially heat resistant and accordingly it will withstand heat generated within the housing and also high ambient temperatures. Also, the construction will allow high temperature manufacturing techniques, such as soldering, brazing or welding, to be employed. The design of the switch permits the rugged construction which will withstand frequent operation without requiring maintenance. It is contemplated that the switch may be utilized in any of various devices for operation by hand, foot, elbow, etc., inasmuch as only very short, momentary movements need be imparted thereto. Also, the movements may be imparted by various kinds of mechanical devices or by electromagnetic devices.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a side elevational view of the switch illustrating the external housing construction;

FIGURE 2 is a front end elevational view of the switch illustrating particularly the elastic diaphragm;

FIGURE 3 is a rear end elevational view of the switch illustrating particularly the terminal connections thereto;

FIGURE 4 is a vertical sectional view taken substantially along the plane 4-4 of FIGURE 2;

3,015,010 Patented Dec. 26, 1961 FEGURE 5 is an elevational plan view of the switch assembly supported within the housing;

FIGURE 6 is a vertical sectional view of the switch assembly taken substantially along the plane 6-6 of FIG- URE 5; and

FIGURE 7 is a vertical sectional view taken substantially along the plane 7-7 of FIGURE 5.

With continuing reference to the drawings and initial reference to FIGURES 1 through 4, numeral 10 generally represents the environment free switch comprising this invention and including a cylindrical housing 12 formed of metal and receiving a metallic end plate 14 therein. The end plate 14 has a pair of cylindrical insulators l6 and 18 extending therethrough and receiving conductors 2G and 22 respectively terminating in

contacts

24 and 26. The contact 24 has a spring 28 connected thereto and terminally carries a contact 30 in alignment with contact 26.

An elastic diaphragm 32 is fitted over the end of the housing 12 remote from the end plate 14. The diaphragm 32 is made of thin, highly elastic material such' as spring steel, spring brass, or the like and is formed into a series of concentric corrugations 34. The particular corrugated construction provides a rugged structure which will not be adversely affected by wear. weathering, aging or ordinary physical abuse. Also, sufiicient elasticity is provided to operate a switch actuator within the housing 12 in a manner to be more particularly described below. A switch assembly, generally designated by the numeral 36 is supported in the housing 12 by a support 38 extending from the end plate 14. A rivet 40 connects the base 42 of the switch assembly 36 to the support 38.

Attention is now drawn to FIGURES 5 through 7 wherein the details of the switch assembly 36 are illustrated. The numeral 42 indicates the switch assembly base and includes a vertical leg 44 and a horizontal leg 46 including a reduced portion 48. Extending through the vertical leg 44 is a rod 50 having a head 52. A spring 54 is received around the rod Stl between the head 52 and vertical leg 44. Secured to the rod 50 is a driving head 56. The driving head 56 includes a downturned leg 58 which defines an opening 61 therein for passing the reduced portion 48 of the base horizontal leg 46. The driving head 56 is adapted to control the position of a cradle 66 through a motion transmitting mechanism to be further defined.

The cradle 60 is a U-shaped structure including

leg portions

62 and 64 and bight portion 66. The bight portion 66 has a reduced lower portion 68 which defines an opening 70 therein through which the reduced portion 48 of the horizontal base leg 46 passes. The

leg portions

62 and 64 pass through

slots

72 and 74 in the vertical leg 44 of the base 42. Accordingly, the leg portion sliding in the vertical leg 44 and the bight portion sliding on the base 42 assures cradle movement in a straight line. The cradle 69 is urged toward a position proximate to the diaphragm 32 by the contact spring 28 which may be supplemented by an auxiliary spring. An insulator 76 is secured to the bight portion 66 of the cradle 60 and insulates the contact spring 28 from the cradle 60.

The motion transmitting mechanism heretofore mentioned includes a driving pawl 78 and a latching pawl 80. Each of the

pawls

78 and 86 are L-shaped structures having vertical and horizontal legs. Springs 82 and 84 are afiixed to the bight portion 66 of the cradle 60 by 'fastener 87 and the

springs

82 and 84 respectively ex- 78. The spring 90 urges the arm 88 upwardly with respect to the driving pawl 78 and the movement is limited by a trip pin 92 secured to the driving pawl 78 and extending through an opening 94 carried on the lower edge of the arm 88. The arm 88 has a guide pin 96 secured to the end thereof. The driving head 56 has an upper surface 98 and a lower surface 1630 providing a step or abutment 102 therebetween. The free end of the driving pawl 78 cooperates with the

surfaces

98 and 100 and the step 102 in driving the cradle 60. An upturned leg 194 is formed over to provide a projection -of cross-section 1116. The projection 106 cooperates with the guide pin 96 on the arm 88 in controlling the action of the motion transmitting mechanism.

The latching pawl 80 engages a stop surface 108 which is attached to the base 42. The step surface 103 has an upper surface 110 and a lower surface 112. The surfaces 110 and 112 define a step 114 therebetween, the cradle 60 is locked in its forward position with the

conductors

20 and 22 bridged when the latching pawl 80 is in engagement with the step 114.

In the operation of the device, the diaphragm 34 is depressed to move the switch actuator or rod 54). With the dimensions contemplated, it is only necessary to depress the diaphragm approximately /8 of an inch. It shall be assumed that in the initial position, the driving pawl 78 rests on the lower surface 100 in engagement with the step 102 of the driving head 56. The latching pawl 80 rests on the upper surface 111) back of the step 114 of the step surface 108. FIGURES 5 through 7 illustrate the switch assembly in the initial position. Both pawls are tensioned in their respective positions by

springs

82 and 84. The arm 88 is tensioned upward by spring 90 such that the bottom of the opening 94 bears against the trip pin 92. The guide pin 96 on the free end of arm 88 is positioned in back of the inclined surface of the projection 106 of the driving head 56. The driving head 56 is tensioned toward the rear by the spring 54 bearing against head 52. The cradle 60 is likewise tensioned to the rear by the spring 28 acting against the insulator 76. Therefore,

conductors

20 and 22 will remain open.

It shall now be assumed that pressure is applied to the diaphragm 32 moving the rod 50 and driving head 56 forwardly. The cradle 60 will also be driven forward by the driving pawl 78 bearing against the step 102 on the driving head 56. Insulator 76 will be carried forwardly and bearing against the spring 28 so as to engage the

contacts

30 and 26 to bridge the

conductors

20 and 22. Simultaneously, the latching pawl 80 travels along the upper surface 110 and drops to the lower surface 112 so as to bear against the step 1-14. The cradle 60 is then locked in its forward position thus maintaining the

conductors

20 and 22 bridged.

When pressure on the diaphragm 32 is released, the driving head 56 is urged to its rearward position by spring 54. As the driving head 56 moves rearwardly, the lower surface 100 of the driving head 56 moves relative to the pawl 78. At the same time, the guide pin 96 is riding along the lower or rear of the inclined surface'106 of the projection 106 and the free end of the arm 88 is forced downwardly against the tension of spring 91). When the pin 96 passes the projection 106, spring 90 relaxes and the arm 88 springs up so that the pin 96 is then positioned forwardly of the projection 106. The switch assembly still maintains the

conductors

20 and 22 bridged. When it is desired to disengage the

contacts

26 and 30, pressure is again applied to the corrugated diaphragm 32 and again the driving head 56 is moved forwardly. The guide pin 96 now rides up the forward or upper face of the projection 106 and the free end of the arm 88 is forced upwardly. The bottom of the opening 94 of the arm 88 acts against the trip pin 92 so as to raise the driving pawl 78 and latching pawl 80, releasing the cradle 60 which is then urged to its rearward position by spring 28. Of course,

contacts

26 and 30 will become disengaged.

Then, when the pressure of the diaphragm 32 is released, the driving head 56 is urged to its rearward position by spring 54 and the switch assembly is again in position to be operated.

From the above, it will be appreciated that a novel switch construction has been disclosed wherein the elements of the switch assembly are sealed within a housing so as to divorce the working elements from harmful environmental effect.

The foregoing is considered as illustrative only of the principies of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. An environment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, switch assembly means having retracted and extended conditions and movably supported in said housing for movement while in one of said conditions in response to displacing engagement of said diaphragm, and biasing contact means connected to one of said spaced terminals within the housing and operative to make or break contact with the other of said terminals and change the condition of said switch assembly means in response to engagement of said diaphragm.

2. The combination of claim 1 wherein said switch assembly means including a switch actuator means disposed adjacent to said diaphragm for manual depression thereof therethrough, and operatively connected to the biasing means when the switch assembly means is in extended condition for making contact with the other terminal and operative when the switch assembly means is in retracted condition to release the biasing means for breaking contact.

3. The combination of claim 2 wherein said switch assembly means further includes means for holding the switch assembly means in either retracted or extended condition and thereby operatively connect said switch actuator means to said biasing contact means for selectively retaining said contact means in either an open contact or bridged closed contact position.

4. The combination ofclaim 3 wherein said holding means including a base supported in said housing, for slidably mounting the switch actuator means, and spring means supported between said base and said actuator means for urging said actuator toward said diaphragm.

5. An environment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator to said bridging element for selectively retaining said element in either an open or bridged position, said means including a base supported in said housing, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle.

6. An environment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator to said bridging element for selectively retaining said element in either an open or bridged position, said means including a base supported in said housing, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle, stepped surface secured to said base and aligned with said latching pawl whereby said latching pawl may abut said stepped surface to prevent slidable movement of said cradle.

7. An environ-ment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator tosaid bridging element for selectively retaining said element in either an open or bridged position, said means including a base supported in said housing, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle, stepped surface secured to said base and aligned with said latching pawl whereby said latching pawl may abut said stepped surface to prevent slidable movement of said cradle, an arm, each of said driving pawl, latching pawl and arm pivotally mounted on a common axis supported by said cradle, a pin secured to said driving pawl and receivable through an opening in said arm, said driving pin abutting said latching pawl.

8. An environment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator to said bridging element for selectively retaining said element in either an open or bridged position, said means including a base supported in said housing, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle, stepped surface secured to said base and aligned with said latching pawl whereby said latching pawl may abut said stepped surface to prevent slidable movement of said cradle, an arm, each of said driving pawl, latching pawl and arm pivotally mounted on a common axis supported by said cradle, a pin secured to said driving pawl and receivable through an opening in said arm, said pin abutting said latching pawl, spring means supported between said housing and said pawls for respectively urging said driving pawl and said latching pawl into engagement with said driving head and said stepped surface.

9. An environment free switch comprising a sealed housing, a pair of spaced terminals extending in'o said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator to said bridging element for selectively retaining said element in either an open or ridged position, said means including a base supported in said housing, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle, stepped surface secured to said base and aligned with said latching pawl whereby said latching pawl may abut said stepped surface to prevent slidable movement of said cradle, an arm, each of said driving pawl, latching pawl and arm pivotally mounted on a common axis supported by said cradle, a pin secured to said driving pawl and receivable through an opening in said arm, said pin abutting said latching pawl, spring means supported between said housing and said pawls for respectively urging said driving pawl and said latching pawl into engagement with said driving head and said stepped surface, an inclined surface, a guide pin carried by said arm, and a spring secured between said driving pawl and said arm for urging said guide pin into engagement with said inclined surface.

10. An environment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator to said bridging element for selectively retaining said element in either an open or bridged position, said means including a base supported in said housing, said switch actuator mounted for reciprocably slidable movement through said base, and spring means supported between said base and said actuator for urging said actuator toward said diaphragm, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle.

11. An environment free switch comprising a sealed housing, a pair of spaced terminals extending into said housing, an elastic diaphragm comprising one wall of said housing, a switch assembly supported in said housing and actuatable through said diaphragm for bridging said spaced terminals, said switch assembly including a switch actuator disposed adjacent to said diaphragm whereby said actuator may be manually depressed through said diaphragm, a bridging element, means operatively connecting said switch actuator to said bridging element for selectively retaining said element in either an open or bridged position, said means including a base supported in said housing, said switch actuator mounted for reciprocably slidable movement through said base, and spring means supported between said base and said actuator for urging said actuator toward said diaphragm, a cradle slidable upon said base, said cradle supporting a driving pawl and a latching pawl, a driving head, said driving head secured to said actuator and slidable on said base, said driving head aligned with said driving pawl whereby slidable movement of said actuator may slidably drive said cradle, said base including a vertical leg and a horizontal leg, said horizontal leg defining a reduced portion, said cradle being of a U-shape defining a bight portion and a pair of leg portions, said reduced portion of said horizontal leg extending through said bight portion, said leg portions extending through said vertical leg.

References Cited in the file, of this patent UNITED STATES PATENTS Schellman Oct. 12, 1948