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Publication numberUS3649788 A
Publication typeGrant
Publication dateMar 14, 1972
Filing dateJul 6, 1970
Priority dateJul 6, 1970
Publication numberUS 3649788 A, US 3649788A, US-A-3649788, US3649788 A, US3649788A
InventorsHeckendorf Howard A
Original AssigneeGen Motors Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Acceleration responsive switch
US 3649788 A
Abstract
An acceleration responsive switch includes a housing mounting a pair of spaced fixed contacts connected across a source of power. The housing includes a cylindrical lateral extension which slidably receives a pushbutton and a release plate. A coil compression spring seating on one apertured wall of the housing holds the release plate in engagement with the pushbutton to hold the pushbutton in engagement with the other apertured wall. An operator is slidably mounted within a guide portion of the release plate. A movable contact for bridging the fixed contacts is slidably mounted on the operator and spring biased to a position connecting the fixed contacts. A plurality of balls are slidably mounted within respective radial bores of the operator for movement inwardly of the bores or outwardly thereof. In the latter position, the balls are axially engageable between the walls of the bores and a radial shoulder of the release plate to locate the operator in a first position against a spring bias to a second position. The balls are forced outwardly of the bores by an axial pin which is secured to a generally frustoconically shaped seismic mass seating on the release plate. A magnet on the mass exerts a predetermined flux between the mass and plate to normally locate the mass in seated position unless an acceleration pulse of predetermined amplitude and time is applied to the mass. When such a pulse is received, the control pin is withdrawn from engagement with the balls to permit the balls to move inwardly of the bores and release the operator for movement under its spring bias to its second position. The operator engages the movable contact as the operator moves to its second position to open the switch. The switch can be reset in closed position by manually moving the pushbutton inwardly of the extension. This moves the release plate, the mass and the button toward the operator to locate the radial shoulder of the plate with respect to the radial bores of the operator and simultaneously engage the control pin with the balls to force the balls into engagement with such radial shoulder. This reconnects the release plate and operator, and the spring of the release plate returns the operator to its first position and likewise returns the release plate and pushbutton to their normal position to reset the switch.
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Description  (OCR text may contain errors)

United States Patent Heckendorf Mar. 14, 1972 [54] ACCELERATION RESPONSIVE SWITCH Howard A. Heckendorf, Brookfield, Wis.

[73] Assignee: General Motors Corporation, Detroit,

Mich.

22 Filed: July 6,1970

21 Appl.No.: 52,244

[72] inventor:

Primary Examiner-J. V. Truhe Assistant Examiner-George A. Montanye Attorney-W. E. Finken and Herbert Furman [57] ABSTRACT An acceleration responsive switch includes a housing mounting a pair of spaced fixed contacts connected across a source of power. The housing includes a cylindrical lateral extension which slidably receives a pushbutton and a release plate. A coil compression spring seating on one apertured wall of the housing holds the release plate in engagement with the pushbutton to hold the pushbutton in engagement with the other apertured wall. An operator is slidably mounted within a guide portion of the release plate. A movable contact for bridging the fixed contacts is slidably mounted on the operator and spring biased to a position connecting the fixed contacts. A plurality of balls are slidably mounted within respective radial bores of the operator for movement inwardly of the bores or outwardly thereof. In the latter position, the balls are axially engageable between the walls of the bores and a radial I shoulder of the release plate to locatethe operator in a first position against a spring bias to a second position. The balls are forced outwardly of the bores by an axial pin which is secured to a generally frustoconically shaped seismic mass seating on the release plate. A magnet on the mass exerts a predetermined fiux between the mass and plate to normally locate the mass in seated position unless an acceleration pulse of predetermined amplitude and time is applied to the mass. When such a pulse is received, the control pin is withdrawn from engagement with the balls to permit the balls to move inwardly of the bores and release the operator for movement under its spring bias to its second position. The operator engages the movable contact as the operator moves to its second position to open the switch. The switch can be reset in closed position by manually moving the pushbutton inwardly of the extension. This moves the release plate, the mass and the button toward the operator to locate the radial shoulder of the plate with respect to the radial bores of the operator and simultaneously engage the control pin with the balls to force the balls into engagement with such radial shoulder. This reconnects the release plate and operator, and the spring of the release plate returns the operator to its first position and likewise returns the release plate and pushbutton to their normal position to reset the switch.

6 Claims, 3 Drawing Figures This invention relates generally to acceleration responsive switches and more particularly to such switches which automatically open a circuit when an acceleration pulse of predetermined amplitude and time is received and which can be selectively reset without disassembly.

One of the features of this invention is that it provides an improved acceleration responsive normally closed switch which includes an operator movable axially from a normal first position to a second position to open the switch, with the operator being normally held against movement by a plurality of balls engaging axially spaced generally radially extending cooperating surfaces on the operator and a movable release member, and with the movement of the balls into and out of engagement with the cooperating surfaces being controlled by a seismic mass arrangement. Another feature is that the release member can be moved relative to the operator when the latter is in second position to locate the cooperating surfaces in a position to receive the balls therebetween', with the release member and operator being subsequently movable as a unit to return the operator to the first position and permit the switch to close. A further feature of this invention is that the I balls are normally forced outwardly of radial bores in the operator and into engagement with a radial shoulder of the release member by an axially movable pin, the movement of which is controlled by a seismiemass seated on the release member under the action of a predetermined strength magnetic flux which is overcome when an acceleration pulse of predetermined amplitude and time is applied to the mass.

These and other features of the switch of this invention will be readily apparent from the following specification and drawings wherein:

FIG. 1 is a view showing the switch in closed position;

FIG. 2 is a view similar to FIG. 1 showing the switch in open position; and

FIG. 3 is a sectional view taken generally along the plane indicated by line 3-3 of FIG. 2.

Referring now particularly to FIGS. 1 and 2 of the drawings, a switch designated generally according to this invention includes a generally rectangularly shaped baseplate 12 of insulating material and a generally rectangularly shaped hollow housing 14 of insulating material, the sidewall of which seats on a gasket 16 on the upper surface of plate 12. Diagonally opposite corners of the housing 14 are provided with integral lugs 18 which seat on the gasket 16. Screws, not shown, extend through apertures in the plate 12 and into such lugs to secure the plate 12 and housing 14 to each other. Likewise, aligned apertures in such lugs and in the plate provide for mounting of the switch 10 on any suitable support, such as a vehicle. The switch 10 of this invention could be used in such a vehicle to disconnect the battery from the electrically operated. mechanisms and accessories in the event that the vehicle receives an acceleration pulse, due to impact or otherwise, which exceeds a predetermined amplitude and time.

A pair of switch contacts 20 extend through apertures in the upper wall of housing 14 at the other diagonal comers thereof, and each includes an elongated contact portion 22 located along a diagonal through suchother comers of the housing, and a threaded portion 24 which is secured to the upper wall of the housing by a pair of nuts 26 and a washer 28.

An integral cylindrical extension 30 extends generally normal to the upper wall of housing 14 and including an apertured one end wall 32. A hollow pushbutton 34 of insulating material is slidably mounted within the extension 30. and includes a button portion 36 which extends outwardly of the aperture in wall 32 when the pushbutton is in its position as shown. A circular metal plate or release member 38 is slidably received in extension 30 and seats against the open end of the pushbutton 34. A coil compression spring 40 seats between plate 38 and an apertured circular plate 42 at the open end of extension 30 and biases the plate 38 upwardly to in turn bias the pushbutton 34 upwardly and locate an annular shoulder 44 thereof in engagement with the wall 32 adjacent the aperture therein. Any suitable resilient washer can be provided on the shoulder 44. Plate 42' is held within a counterbore of extension 30 by contact portions 22.

A cylindrical operator 46 is slidably received within a tubular guide or portion 48 of the plate 38. A split ring spn'ng seat" 50 received within an intermediate annular groove of the operator seats one end of a coil compression spring 52, the other end of which seats on the lower surface of plate 38 to continually bias the operator 46 downwardly as viewed in FIG. 1. The operator 48 includesthree equally spaced radial bores 54, FIG. 3, which open to a central axial bore of the operator. A ball 56 is slidably received in each bore. When the balls tangentially engage the walls of the respective boxes and the axially juxtaposed radially and axially extendingannular shoulder 58 of the plate 38, as shown in FIG. 1,. the operator 46- is located in what may be termed its first position and held against movement by s'pring'52 to its second position shown in FIG. 2. In order for the operator to move to its second or FIG. 2 position, balls 56 must move radially inwardly of bores 54 and out of tangential engagement with shoulder 58.

A control pin or member 60 controls the radial movement of the balls 56 and is movable relative to the balls within the central axial bore of the operator 46. Pin 60 is secured to a hollow seismic mass 62 of predetermined weight and of generally frustoconical shape which seats on the plate 38' and is held thereagainst by an annularpermanent magnet 64'which is secured to the mass and exerts a predetermined strength flux between the mass and the plate. The seismic mass 62 normally maintains the control pin 60 in its positionas shown in FIG. 1. In this position, the pin 60 tangentially engages the three balls 56 and forces the balls radially outward of bores 54 into tangential engagement with shoulder 58 'to retain the operator 46 in its first position. When the mass is subjected to an acceleration pulse of predetermined amplitude'and time, the mass will tilt relative to the plate 38 to itsposition shown in FIG. 2. This movement of the mass partially withdrawsthe pin 60 from the axial bore of the operator and permits the balls 56 to move radially inwardly of the bores 54 and out of engagement with shoulder 58 to release the operator 46 for movement to its second position shown in FIG. 2. The tapering of the shoulder 58 axially of the operator 46 aids the spring 52in camming the balls 56 radially inwardly ofbores 54 to permit movement of the operator to its second position. The guide 48 retains the balls within their respective bores as-the operator moves to its second position.

A flanged bushing 66 of insulating material is slidably. mounted onthe operator 46 and received within a central aperture of the plate 42. A circular contact 68 seatsagainst the flange of bushing 66 and is held thereagainst by being piloted on a flanged washer 70 of insulating material which is slidably mounted on the operator 46 andbiases the contact 68 upwardly under the action of a coil compression spring 72 which seats on thebase of a bore 74 in the plate 12 andalso against the washer 70.

When the operator 46 is in'its position shown in FIG. 1, the contact 68 bridges the contact portions 22 so that the'switch is closed and the circuit across the switch is complete.

As previously described, when the seismic mass 62 receives an acceleration pulse of predetermined amplitude and time the balls 56will move inwardly of the operator, and the operator thereupon will immediately move downwardly to its second position, shown in FIG. 2, under the action of the spring 52. As the operator moves to this position, the split ring 50 first engages the bushing 66 and then the plate 42. when the ring 50 engages the bushing 66, it moves the bushing, contact 68 and washer 70 slightly downwardly as shown in FIG. 2.

This moves the contact 68 out of electrical'connection with the contact portions 22 so that the switch is openand the circuit across the switch is open. Upon cessation or reductionof the acceleration pulse, the mass 62 will return from its FIG. 2 position to a position in engagement with plate 38, not shown; However, the length of the pin 60 is such that the pin will not engage the balls 56 when the operator is in its second position and the mass returns to its normal position.

If it is desired to manually reset the switch, the operator engages the button portion 36 and depresses the button 34. This moves the mass 62 and the plate 38 downwardly of their position shown in FIG. 2 so that the bores 54 now open to the radia] shoulder 58 of the plate 38. Likewise, this moves the control pin 60 into engagement with the balls 56 to again force the balls radially outwardly of the bores 54 and into engagement with the shoulder 58. Thus, the plate 38 and the operator 46 are again connected. When the button portion 36 is released, the spring 40 immediately returns the plate 38 and mass 62 to their position shown in FIG. 1. The operator 46 moves with the plate 38 to this position to permit spring 72 to locate con tact 68 in electrical contact with the contact portions 22 and close the switch.

Thus, this invention provides an improved acceleration responsive switch.

lclaim:

1. An acceleration responsive switch, comprising, a support including a pair of spaced electrical contacts, a release member movably mounted on the support, means locating the release member in a predetermined first position, an operator mounted on the release member for axial movement relative thereto between first and secondvpositions, means biasing the operator to the second position, detent means acting between the operator and release member movable between detented and undetented positions and engageable in detented position with the operator to hold the operator in the first position, a seismic mass movably mounted on the support, means operatively connecting the mass to the detent means for movement of the detent means to undetented position to release the operator for movement to the second position upon movement of the seismic mass relative to the support, magnetic means exerting a magnetic flux of predetermined strength between the mass and support to retain the seismic mass against movement relative to the support, an acceleration pulse of predetermined amplitude and time moving the seismic mass relative to the support against the flux of the magnetic means to release the operator, contact means normally electrically connecting the spaced contacts, means disconnecting the contact means and spaced contacts upon movement of the operator to second position, and means for moving the detent means to detented position in engagement with the operator upon movement ofthe release member from the predetermined first position when the operator is in the second position.

2. The switch recited in claim 1 wherein the locating means for the release member includes resilient means holding the release member against stop means on the support, the resilient means returning the release member to the predetermined first position thereof as a unit with the release member upon movement of the detent means to detented position in engagement with the operator when the operator is in the second position.

3. The switch recited in claim 1 wherein the means for moving the detent means to detented position include externally operated manual means for moving the release member relative to the support when the operator is in the second position.

4. The switch recited in claim 1 wherein the locating means includes stop means on the support and resilient means biasing the release member into engagement with the stop means for locating the release member in a predetermined first position, the detent means including means carried by the operator and engageable with the release member in the first positions of the operator and release member, the means for moving the detent means to detented position including externally operated means for moving the release member relative to the support and against the resilient biasing means to a second position wherein the means carried by the operator is engageable with the release member, the resilient biasing means returning the release member and operator as a unit to the first position thereof.

5. An acceleration responsive switch comprising, in combination, a support including a pair of spaced electrical contacts, a pair of members mounted on the support for axial movement relative one another and the support between respective first and second positions, contact means mounted on one member and electrically connecting the spaced contacts in the first position of the one member and disconnecting such contacts in the second position thereof, means biasing the one member to the second position thereof, means normally locating the other member in the first position thereof, the members each including generally radially extending shoulder means located in axially spaced juxtaposed relationship when the members are located in the same number position and located out ofjuxtaposed relationship when the members are located in a different number position, ball means mounted on the one member for movement radially thereof between a first position in engagement with the juxtaposed shoulder means to connect the one member to the other member and locate the one member in the first position thereof against the action of the biasing means, and a second position out of engagement with the shoulder means of the other member to permit movement of the one member to the second position thereof under the action ofthe biasing means. a seismic mass, means mounting the mass on the support for movement relative thereto when subjected to an acceleration pulse of predetermined amplitude and time, means on the mass engageable with the ball means to normally hold the ball means in the first position thereof and being movable out of engagement with the ball means upon movement of the mass relative to the support to permit movement thereof to the second position, and means for moving the other member to the second position thereof when the one member is in the second position thereof to move the shoulder means of the other member into axially spaced juxtaposed relationship and move the engageable means into engagement with the ball means to move the ball means to the first position thereof, the locating means returning the other member and the one member as a unit therewith to the respective first positions thereof.

6. An acceleration responsive switch comprising, in combination, a support including a pair of spaced electrical contacts, an operator member mounted on the support for axial movement between first and second positions relative thereto, contact means mounted on the operator member and electri cally connecting the spaced contacts in the first position of the operator member and disconnecting such contacts in the second position thereof, means biasing the operator member to the second position thereof, a release member mounted on the support for axial movement relative to the operator member, means locating release member in a first position thereof and resisting movement thereof to a second position thereof, the operator and release members each including generally radially extending shoulder means located in axially spaced juxtaposed relationship when the operator member is in the first position thereof and located out of juxtaposed relationship when the operator member is in the second position thereof, ball means mounted on the operator member for movement radially thereof between a first position in engagement with the juxtaposed shoulder means to locate the operator member in the first position thereof against the action of the biasing means and a second position out of engagement with the shoulder means of the release member to permit movement of the operator member to the second position thereof, seismic mass means mounted on the support and moving when subjected to an acceleration pulse of predetermined amplitude and time, means mounted on the seismic mass and engageable with the ball means to normally hold the ball means in the first position thereof and moving out of engagement' with the ball means upon movement of the seismic mass to permit movement of the ball means to the second position, and means for moving the release member to the second position thereof when the operator member is in the second position thereof to move the shoulder means into axially spaced juxtaposed relationship and move the means mounted on the seismic mass into engagement with the ball means to move the ball means to the first position thereof, the

locating means for the release member returning the release member and the operator member as a unit therewith to the respective first positions thereof.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2254294 *Aug 8, 1940Sep 2, 1941Kimmell Lennie VSwitch
US2802204 *May 10, 1954Aug 6, 1957Kennelly Francis XAcceleration operated switch
US2986614 *Jun 24, 1958May 30, 1961Raymond MinchAutomatic safety cutout switch system for use in a motor vehicle
US3500007 *Jan 31, 1968Mar 10, 1970Talley IndustriesInertia-sensitive circuit breaker
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IT625512A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5539935 *Jun 6, 1995Jul 30, 1996Rush, Iii; Gus A.Sports helmet
US5621922 *Dec 20, 1995Apr 22, 1997Rush, Iii; Gus A.Sports helmet capable of sensing linear and rotational forces
US6647788 *Jul 20, 2001Nov 18, 2003Mitsubishi Denki Kabushiki KaishaAcceleration detecting device
US6689016 *Jun 29, 2001Feb 10, 2004Ab Elektronik GmbhMethod and apparatus for producing downshift signals
Classifications
U.S. Classification200/61.45R, 200/61.45M, 340/669
International ClassificationH01H35/14
Cooperative ClassificationH01H35/143, H01H35/14
European ClassificationH01H35/14