EP0043518B1

EP0043518B1 - Switch for auxiliary motor vehicle circuits

Info

Publication number: EP0043518B1
Application number: EP19810104963
Authority: EP
Inventors: Giovanni Foggini
Original assignee: Lear SNC di Foggini and C
Current assignee: Lear SNC di Foggini and C
Priority date: 1980-07-03
Filing date: 1981-06-26
Publication date: 1985-06-05
Also published as: IT8053352V0; DE3170825D1; EP0043518A3; EP0043518A2

Description

This invention relates to a switch for auxiliary motorvehicle circuits in general, and particularly for the circuits of the so-called courtesy lamps, with the features according to the first part of claim 1. The term circuits of courtesy lamps designates herein those circuits which are intended to turn on one or more interior lighting lamps in the passenger compartment or other compartments of motorvehicles which are closed by means of doors or protected by gates, upon opening said doors or gates.
For controlling the foregoing auxiliary circuits, it is current practice to use pushbutton switches the body or base whereof is secured to the uprights, or respectively to the peripheral edge, of the compartment, the movable pushbutton of said switch being engaged by the door higedly mounted on said upright, or respectively by the compartment gate, while said door or gate are in their closed positions. The pushbutton has a movable contact which is urged to engage a corresponding fixed contact by the action of a spring, and said contacts are separated, in order to break the circuit electrical continuity, by the action of said door or gate, which move the pushbutton against the bias of the spring.
Such switches have some drawbacks, being above all liable to jamming with some frequency owing to the penetration of water and dirt therein, difficult to install, and what is more important, complicated construction-wise, so that their ultimate cost can be considered excessive with regard to their function.
From British Patent Specification GB-A-1041676 there is known a switch of the type defined in the pre-characterizing clause of claim 1, in which, however, the deformation of the block is obtained only through axial compression of the elastomeric material of the block. Axial deformation only of elastomeric material is not reliable over the long run and in addition the displace- ment/deformation ratio cannot be multiplied.
Thus the invention sets out to eliminate such drawbacks, by providing a switch-particularly useful for the circuits specified hereinabove-which while being extremely simple is reliable in operation, over the long run and while being easy to install, diversifies the origin of its resiliency.
This problem is solved by the invention contained in claim 1.
The free end of the contact foil or reed is provided with an extension in the form of a "Faston" connector for receiving a corresponding terminal of the circuit lead, and the elastomeric material block, advantageously formed with a polygonal contour, has a groove adapted for receiving the edge of a corresponding polygonal opening formed in the vehicle body metal sheet.
Thus, the switch can be quicly and easily installed by deforming the block to engage said edge with said groove, the reverse operation enabling the removal of the switch.
Further features and advantages will become apparent from the following detailed description, in conjunction with the accompanying drawing, where:

Figure 1 is a cross-sectional view of a switch according to the invention, showing it as installed;
Figure 2 is a top plan view of said switch;
Figure 3 is a front elevation view thereof; and
Figures 4 and 4a are side elevation views showing the switch in the closed and open conditions thereof, respectively.

As may be noted from the drawings, this switch comprises essentially a block 10 of an elastomeric material, advantageously of either natural or synthetic rubber, which has a protruding portion 11 capable of undergoing elastic fold-over deformation relatively to the block. The portion 11 incorporates one leg 12a of a metal strip contact 12, of substantially C-like configuration; said contact being indeformable and advantageously formed from either hard bronze or brass.
The other leg 12_b of the contact 12 is free and has an extended end 12_c in the form of a connector, advantageously of the pin-type, and adapted for receiving a corresponding terminal provided at the end of the circuit lead (not shown). Said free end 12_b of the contact 12 is adapted for engaging a fixed contact 13 forming a ground connection and comprising a screw or the like, which is provided in a corresponding opening adjacent the switch, with the protruding portion 11 in the non-deformed condition. By contrast, when a force is applied to the portion 11 which tends to press it onto the block 10 the end 12_b of the strip contact 12 is caused to rotate and move away from the fixed contact 13, thus breaking the electrical circuit.
It will be appreciated, therefore, how by installing the switch I on a fixed portion of the vehicle body, such as on an upright M, with the protruding portion 11 facing the movable portion formed by the door or gate P (Figures 4-4a) and the door or gate in the open position, the portion 11 will be in the non-deformed condition 11a, thereby the free end 12_b of the contact strip 12 can engage the fixed contact 13 to close the circuit (Figure 4). By constrast, in the closed position, the door or gate will squeeze the portion 11 and cause said strip portion to separate from the fixed contact 13 (Figure 4a), thus opening the circuit.
As shown in the drawing, the block 10 is provided with a peripheral groove 10a adapted for receiving the edge of a corresponding opening formed through the metal sheet L of the vehicle body, thereby the switch can be readily mounted and removed by elastically deforming the block such as to mutually engage, respectively disengage, said groove and edge. Advantageously, to prevent the switch for rotating relatively to the seat, the contour of the block and corresponding edge are made polygonal.

Claims

1. A switch for auxialiary motor vehicle circuits, and particularly for courtesy lamp circuits, which switch comprises a block (10) of an elastomeric material to be inserted into an opening formed in the vehicle body, this block (10) having a resilient portion (11) protruding out of the opening in the vehicle body to be deformed by the door or gate pressure when the door or gate (P) is closed, the block (10) further carrying a movable electric contact (12) which engages with a fixed electrical contact (13) when the resilient portion (11) of the switch block (10) is not deformed, thereby maintaining an electric circuit closed, and which movable contact (12) disengages from the fixed contact (13) when the resilient portion (11) of switch block (10) is deformed characterized in that the resilient deformable portion (11) of the switch block (10) has such a configuration, that it undergoes elastic fold-over deformation relatively to the block (10) when the door or gate (P) is closed, that one end (12a) of an indeformably substantially C-like metal strip forming said movable contact (12) is embedded in said portion (11) capable of undergoing fold-over deformation and that the inner side of the free end (12b) of the C-like movable contact (12) lies opposite the fixed electrical contact (13).

2. A switch according to Claim 1, wherein the free end (12_b) of the metal strip contact is provided with an extension (12_c) in the form of a connector for receiving a corresponding terminal of the electric circuit lead.

3. A switch according to Claim 1 or 2, wherein said elastomeric material block (10) has a groove (10a) adapted for receiving the edge of the corresponding opening formed through the vehicle body metal sheet, the switch being installed and removed by elastically deforming said block (10).

4. A switch according to one of the preceding claims, wherein the block (10) has such a contour as to fit that of the corresponding opening in the vehicle body metal sheet.

5. A switch according to Claim 4, wherein said contour is of polygonal shape.

6. A switch according to one of the preceding claims, wherein the fixed contact (13) forms a ground connection and comprises a screw arranged adjacent the switch accommodating opening.

7. A switch according to one of the preceding claims, wherein the block and related resilient protruding portion are made of natural or synthetic rubber.