Switch for a Seat Belt Buckle

Abstract

A switch for a belt buckle of a seatbelt device including at least two contact elements (4, 5) abutting on each other or reaching into abutment on each other in a cavity of the switch, wherein at least one of the contact elements (4, 5) is configured as a movable contact spring. An insertion channel (8) is provided into which a belt tongue, a locking part, an ejector (7) or a part movably coupled with one of these parts is insertable and removable at least with a section during the locking and unlocking movement of the belt tongue. A movably supported coupling member (3) protrudes with a first section (10) into the insertion channel (8) and includes a second section (11) associated with the contact spring. The movably supported coupling member (3) abuts via the second section (11) on the contact spring in a position-independent manner.

Claims

1. A switch for a belt buckle of a seatbelt device, the belt buckle receiving a belt tongue, the switch comprising; at least two contact elements abutting on each other or reaching into abutment on each other in a cavity of the switch, wherein at least one of the contact elements is configured as a movable contact spring, an insertion channel into which a portion of one or more of the belt tongue, a locking part, and an ejector is insertable into the belt buckle during a locking movement and removed from the belt buckle during an unlocking movement of the belt tongue, a movably supported coupling member, which protrudes with a first section into the insertion channel and includes a second section coupled with the contact spring, and the movably supported coupling member second section abuts the contact spring.

2. A switch according to claim 1, further comprising; the coupling member and the contact spring are movably guided with respect to each other by an interference-fit engagement.

3. A switch according to claim 2, further comprising; a groove in the contact spring and a projection of the coupling member which projection engages in the groove to provide the movable guidance.

4. A switch according to claim 3, further comprising; the coupling member is pivotably supported and the contact spring is disposed with respect to the coupling member such that the groove is oriented with a longitudinal direction perpendicular to the pivot axis of the coupling member.

5. A switch according to claim 1 further comprising; in the position wherein the coupling member first section protrudes into the insertion channel the contact elements abutting on each other, and the coupling member is fixed in position in at least one direction by an abutment on the contact spring and the abutting of the contact spring on the other contact element.

6. A switch according to claim 1 further comprising; the coupling member includes at least one bearing pin, via which the coupling member is pivotably supported about a pivot axis, and the first and the second section extend radially outward with respect to the pivot axis.

7. A switch according to claim 6, further comprising; the first and the second section are disposed offset to each other in the longitudinal direction of the bearing pin.

8. A switch according to claim further comprising; the a first distance (A) between the contact point on which the part insertable into the insertion channel comes into abutment on the first section, and the pivot axis is larger than a second distance (B) between the contact point on which the contact spring abuts on the second section, and the pivot axis of the coupling member.

9. A switch according to claim 1 further comprising: wherein the movable contact spring forms an open electrical circuit in the locking movement of the belt buckle.

10. A switch according to claim 1 further comprising: wherein the belt tongue is inserted and removed from the insertion channel in the locking and the unlocking movements.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the following the invention is explained based on a preferred embodiment with reference to the accompanying Figures.

[0019] FIG. 1 shows an inventive switch in accordance with the present invention;

[0020] FIG. 2 shows the switch from FIG. 1 without a cover;

[0021] FIG. 3 shows and large cutaway a section of the switch;

[0022] FIG. 4 shows the coupling member with the abutting contact spring;

[0023] FIG. 5 shows the switch in the closed position of the contact elements; and

[0024] FIG. 6 shows the switch in the open position of the contact elements.

DETAILED DESCRIPTION

[0025] In FIG. 1 an inventive switch with a housing 1 and a cover 2 laterally covering the housing 1 can be seen. The same switch is depicted in FIG. 2 without the cover 2 so that two contact elements 4 and 5 disposed in the housing 1 and a coupling member 3 disposed therein can be seen. The switch further includes an insertion channel 8 that can be seen in FIG. 3, which is closed on one side by the cover 2 and formed by two planar and parallel walls of the switch.

[0026] The lower contact element 5 in the depiction is formed by a curved contact plate, which includes on one end a projection 9 projecting towards the other contact element 4 and is clamped between two walls of the housing 1. The lower contact element 5 can thereby be viewed as fixed. The upper contact element 4 in the depiction is also formed by a curved contact surface, which is clamped with one end between two walls of the housing 1. The free end of the upper contact element 4 protrudes into a free space 13 of the housing 1 and is slightly movable such that it is deliberately arranged so as to be able to perform certain movements for opening and closing the contact. The upper contact element 5 thus forms the movable contact spring.

[0027] The coupling member 3 depicted larger in FIG. 4 includes a rod-shaped bearing pin 12 having a circular cross-section and two end-side bearing sections. The coupling member 3 is pivotably supported about a pivot axis S in the housing 1, which pivot axis S is identical to the longitudinal axis of the bearing pin 12. A first section 10 and a second section 11 extend radially outward from the bearing pin 12. The two sections 10 and 11 are in the form of lever arms, which are disposed adjacent to each other, i.e., offset on the bearing pin 12 in the direction of the longitudinal axis of the bearing pin 12. The two sections 10 and 11 are differently oriented such that the first section 10 in the closed position (i.e. providing a closed electrical circuit) depicted in FIG. 5 of the contact elements 4 and 5 protrudes into the insertion channel 8, and the second section 11 abuts on the underside of the upper contact element 4. The upper contact element abuts in this position on the projection 9 of the lower contact element 5; the electrical contact is thus closed.

[0028] The contact spring, i.e., the upper contact element 4, includes a first strip 14 extending obliquely downward and a retaining section 15 extending in the horizontal direction in the closed position from the strip 14 at an angle. In the closed position the contact spring abuts with the edge of the transition from the strip 14 in the retaining section 15 on the projection 9 of the lower contact element 5, so that a very small, in the ideal case punctiform contact arises between the contact elements 4 and 5. For this purpose the projection 9 is configured strip-shaped and oriented with its longitudinal axis perpendicular to the edge abutting thereon of the upper contact element 4. Furthermore, a groove 16 is provided in the retaining section 15, into which the coupling member 3 engages with a projection 17 provided on the second section 11. The groove 16 and the projection 17 engaging therein form an interference-fit connection of the contact spring and of the coupling member 3, which makes possible a movement of the two parts exclusively in the direction of the longitudinal axis of the groove 16. In the other directions the interference-fit connection forms a securing against an inadvertent slipping of the contact spring from the coupling member 3. The groove 16 is thus oriented and shaped such that its longitudinal axis in the installed state extends perpendicular to the pivot axis S of the coupling member 3 so that the coupling member 3 can pivot about the pivot axis S, while the projection 17 performs a longitudinal movement here in the groove 16.

[0029] When applying the seatbelt, the occupant pushes a belt tongue into a belt buckle (not shown), whereby in the present embodiment, an ejector 7 is pushed into the insertion channel 8. However, instead of the ejector 7 the belt tongue itself, a locking part, or a part movably coupled with one of these parts can be pushed into the insertion channel 8. During the pushing-in movement in the insertion channel 8 the ejector 7 initially comes into abutment on the first section of the coupling member 3, and the coupling member 3 subsequently pivots into the position shown in FIG. 6. Due to the pivoting of the coupling member 3, the contact spring is raised over the second section 11 of the coupling member 3 and the contact between the contact elements 4 and 5 is lifted. This position is also referred to as the open position of the switch (creating an open electrical circuit). Since in the closed position of the switch, the contact spring already abuts on the second section 11 of the coupling member 3, the contact spring is lifted immediately at the start of the pivot movement of the coupling member 3. In addition, the coupling member 3 is simultaneously urged into the insertion channel 8 with the first section 10 by the abutment of the contact spring in the closed position of the switch.

[0030] The distance A between the pivot axis S and the contact surface on which the ejector 7 abuts on the first section 10, is deliberately larger than the distance B between the pivot axis S and the contact surface on which the upper contact element 4 abuts on the second section 11. A translation can thereby be realized, using which the force exerted by the ejector 7 on the coupling member 3 is translated into a larger force exerted by the coupling member 3 onto the contact spring. Furthermore, the path travelled by the second section 11 of the coupling member 3 and by the contact spring can be translated into a shorter path length with respect to the path travelled by the first section 10, so that the required free space 13 can be dimensioned correspondingly small and the required installation space in the belt buckle is only slightly increased by the free space 13.

[0031] The sections 10 and 11 are laterally arranged on the bearing pin 12, i.e., the first section 10 is arranged on one side of the bearing pin 12, while the second section 11 extends outward from the first section 10, towards the center of the bearing pin 12. The sections 10 and 11 are each formed by lever arms, which extend outwards from the bearing pin at different radial angles. The bearing pin 12 extends laterally out over the sections 10 and 11 so that the bearing pin has corresponding free bearing sections at its ends, with which it is pivotably supported in the housing 1.

[0032] The contact of the contact elements 4 and 5 is deliberately disposed in a cavity of the housing 1. Due to the arrangement of the contact it can be protected from entering dirt particles. The transmission of the movement here is deliberately effected by the coupling member 3, which protrudes into the insertion channel with the first section 10 and can accordingly be configured in an abrasion-resistant manner. The coupling member 3 can be embodied, for example, as an injection-molded plastic part. The contact elements 4 and 5 can be manufactured as stamped parts from a metal plate, wherein the shape tolerance can be deliberately chosen larger due to the strip shape of the contact elements 4 and 5 and the inventive permanent abutment of the upper contact element 4 on the second section 11 of the coupling member 3. In addition due to the inventive solution, the contact elements 4 and 5 are only slightly moved for closing and opening the contact, so that the probability of damage can be significantly reduced even after a large number of locking operations of the belt buckle.

[0033] While the above description constitutes the preferred embodiment of the present invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope and fair meaning of the accompanying claims.