LOAD RESPONSIVE SWITCH

• US 3,761,658 A
• Filed: 09/17/1971
• Issued: 09/25/1973
• Est. Priority Date: 09/17/1971
• Status: Expired due to Term

• Current Assignee: Frederick Jean Maltais, Winfield Warren Loose
• Original Assignee: Frederick Jean Maltais, Winfield Warren Loose
• Inventors: Loose, Winfield Warren, Maltais, Frederick Jean
• Primary Examiner(s): Smith, Jr., David
• Application Number:
  US05/181,499
• Time in Patent Office: 739 Days
• Field of Search: 200/85R,86R 307/15B 340/278
• US Class Current: 200/85.00R
• CPC Class Codes: B60R 2022/4858 for sensing pressure on seat
• CPC Class Codes: H01H 3/141 Cushion or mat switches

Abstract

A load responsive switch that is responsive, for example, to the weight of an operator or passenger on the seat of an automobile. The switch is actuated by the deflection of a composite beam comprising upper and lower metal strips which are separated by a plastic spacer. At one end of the beam, the ends of the upper and lower strips are connected to each other. At the other end of the beam, the lower strip is fixed to a housing for the switch, and the corresponding end of the upper strip is free. In this manner, when the beam is flexed in response, for example, to the weight of a driver or passenger on the seat of the automobile, the end of the upper strip moves into the switch housing to change the state of the switch. The housing is provided with a slide member movable longitudinally therein, and a cover for closing the upper portion thereof. Two terminals are contained in the housing and the switch is closed when the contact arms of a bus bar mounted in a slot in the slide member engage the terminals. The plastic slide has a central rib frictionally received between fingers on the end of the upper strip. Overtravel of the upper strip is accommodated by movement of the free end thereof relative to the sides of the central rib of the slide member.

Claims

1. A load responsive switch, comprising:

a housing having circuit opening and closing means, a composite beam, said composite beam comprising first and second, normally unflexed, flexible and resilient strips, said first and second strips being secured together at one end, said first strip being free at the other end thereof and extending into said housing for actuation of said circuit opening and closing means, said second strip being secured at the other end thereof to said housing, said first strip being an elongated corrugated strip, said second strip being an elongated substantially flat strip, and a third elongated substantially flat strip extending over said first strip on the side thereof opposite to that adjacent said second strip, said third strip being secured at one end to said one end of said second strip, whereby when said first and second strips are flexed in response to the application of a load on said composite beam, the free end of said first strip is moved inwardly within said housing to actuate said circuit opening and closing means, and when said load is removed from said composite beam, said first and second strips return to their unflexed positions.

2. A load responsive switch, comprising:

a housing having circuit opening and closing means, a composite beam, said composite beam comprising first and second, normally unflexed, flexible and resilient strips and an elongated spacer disposed therebetween, said first and second strips being secured together at one end, said first strip being free at the other end thereof and extending into said housing for actuation of said circuit opening and closing means, said second strip being secured at the other end thereof to said housing, said circuit opening and closing means including a slide member slidably mounted within said housing, said free end of said first strip being in slidable frictional engagement with said slide member such that said slide member is movable with the free end of said first strip when it is flexed, and the free end of said first strip is movable relative to said slide member when the movement of said slide member in said housing is stopped, a pair of terminals mounted within said housing, said slide member having a transverse slot, and a bus bar mounted within said transverse slot and having a pair of contact arms adapted to engage said terminals when said slide member is in a first position in said housing, whereby when said first and second strips are flexed in response to the application of a load on said composite beam, the free end of said first strip is moved inwardly within said housing to actuate said circuit opening and closing means, and when said load is removed from said composite beam, said first and second strips return to their unflexed positions.

3. The switch of claim 2 wherein said housing comprises a pair of transverse recesses, and said bus bar comprises a pair of spring arms mounted within said transverse recesses, said spring arms urging said contact arms in a direction for engagement with said terminals.

4. The switch of claim 3 wherein, when said first strip is unflexed, said slide member is in a second position within said housing wherein it is in engagement with said bus bar to prevent said contact arms from engaging said terminals, and when said first strip is flexed in rEsponse to the application of a load on said composite beam, said slide member is moved to said first position in said housing wherein the contact arms of said bus bar are urged into engagement with said terminals by said spring arms.

5. A load responsive switch, comprising:

a housing having circuit opening and closing means, a composite beam, said composite beam comprising first and second, normally unflexed, flexible and resilient strips and an elongated spacer disposed therebetween, said first and second strips being secured together at one end, said first strip being free at the other end thereof and extending into said housing for actuation of said circuit opening and closing means, said second strip being secured at the other end thereof to said housing, said circuit opening and closing means including a slide member slidably mounted within said housing, said free end of said first strip being in slidable frictional engagement with said slide member such that said slide member is movable with the free end of said first strip when it is flexed, and the free end of said first strip is movable relative to said slide member when the movement of said slide member in said housing is stopped, said slide member having a central rib, and the free end of said first strip having a longitudinal slot therein that is defined at its outer end by a pair of inwardly extending tabs, said tabs being in frictional sliding engagement with said rib of said slide member, whereby when said first and second strips are flexed in response to the application of a load on said composite beam, the free end of said first strip is moved inwardly within said housing to actuate said circuit opening and closing means, and when said load is removed from said composite beam, said first and second strips return to their unflexed positions.

6. The switch of claim 5 wherein the free end of said first strip is provided with stop means engageable with said housing to limit the inward and outward movement of said free end within said housing.

7. The switch of claim 6 wherein said stop means comprise a pair of tabs extending laterally outwardly from the free end of said first strip, and said housing comprises longitudinally extending recesses in which said stop tabs are movable.

8. A load responsive switch, comprising:

a housing, a slide member longitudinally slidable in said housing, said slide member having a central rib and a transverse slot, a pair of terminals mounted in said housing, a bus bar mounted in said transverse slot of said slide member and having a pair of contact arms positioned for engagement with said terminals, and a composite beam, said composite beam comprising first and second, normally unflexed, flexible and resilient strips and an elongated spacer disposed therebetween, said first and second strips being secured together at one end thereof, said first strip being free at the other end thereof and extending into said housing in slidable frictional engagement with said central rib of said slide member, and said second strip being secured at the other end thereof to said housing, said slide member being movable within said housing between a first position wherein said contact arms of said bus bar are in engagement with said terminals and a second position wherein said contact arms are out of engagement with said terminals, whereby when said first and second strips are flexed in response to the application of a load on said composite beam, the free end of said first strip is moved inwardly within said housing to move said slide member to said first position, and when said load is removed from said composite beam, said first strip is moved outwardly within said housing to move said slide member to said second position.

9. The switch of claim 8 wherein the free end of said first strip has a longitudinally extending slot that is defined at its outer end by a pair of laterally inwardly extending tabs, said tabs being in frictional slidAble engagement with the opposite sides of said central rib of said slide member.

10. The switch of claim 9 wherein the free end of said first strip is provided with laterally outwardly extending stop tabs that are engageable with said housing for limiting the inward and outward movement of said first strip within said housing.

11. The switch of claim 8 wherein said housing comprises a pair of transverse recesses, and said bus bar comprises a pair of spring arms mounted within said recesses, said spring arms serving to urge said contact arms into engagement with said terminals.

12. The switch of claim 8 wherein said first and second strips are substantially flat elongated metal strips.

13. The switch of claim 8 wherein said first strip is an elongated corrugated strip, said second strip is an elongated substantially flat strip, and a third elongated substantially flat strip extends over said first strip on the side thereof opposite to that adjacent said second strip, said third strip being secured at one end thereof to said one end of said second strip.

14. A load responsive switch, comprising:

a housing having circuit opening and closing mens, and a composite beam, said composite beam comprising first and second, normally unflexed, flexible and resilient strips, said first and second strips being secured together at one end, said first strip being free at the other end thereof and extending into said housing for actuation of said circuit opening and closing means, said second strip being secured at the other end thereof to said housing, said first strip being an elongated corrugated strip, said second strip being an elongated substantially flat strip, whereby when said first and second strips are flexed in response to the application of a load on said composite beam, the free end of said first strip is moved inwardly within said housing to actuate said circuit opening and closing means, and when said load is removed from said composite beam, said first and second strips return to their unflexed positions.

15. The switch of claim 14 wherein said circuit opening and closing means comprises a slide member slidably mounted within said housing, said free end of said first strip being in slidable frictional engagement with said slide member such that said slide member is movable with the free end of said first strip when it is flexed, and the free end of said first strip is movable relative to said slide member when the movement of said slide member in said housing is stopped.

16. The switch of claim 15 wherein a pair of terminals are mounted within said housing, said slide member has a transverse slot, and a bus bar is mounted within said transverse slot and has a pair of contact arms adapted to engage said terminals when said slide member is in a first position in said housing.

17. The switch of claim 16 wherein said housing comprises a pair of transverse recesses, and said bus bar comprises a pair of spring arms mounted within said transverse recesses, said spring arms urging said contact arms in a direction for engagement with said terminals.

18. The switch of claim 17 wherein, when said first strip is unflexed, said slide member is in a second position within said housing wherein it is in engagement with said bus bar to prevent said contact arms from engaging said terminals, and when said first strip is flexed in response to the application of a load on said composite beam, said slide member is moved to said first position in said housing wherein the contact arms of said bus bar are urged into engagement with said terminals by said spring arms.

19. The switch of claim 15 wherein said slide member has a central rib, and the free end of said first strip has a longitudinal slot therein that is defined at its outer end by a pair of inwardly extending tabs, said tabs being in frictional sliding engagement with said rib of said slide member.

20. The switch of claim 19 wherein the free end of said first strip is provided with stop meaNs engageable with said housing to limit the inward and outward movement of said free end within said housing.

21. The switch of claim 20 wherein said stop means comprise a pair of tabs extending laterally outwardly from the free end of said first strip, and said housing comprises longitudinally extending recesses in which said stop tabs are movable.