ELONGATED BELT RETRACTOR AND STOP MEANS

• US 3,557,914 A
• Filed: 02/12/1969
• Issued: 01/26/1971
• Est. Priority Date: 02/12/1969
• Status: Expired due to Term

• Current Assignee: Tanaka Akira
• Original Assignee: Tanaka Akira
• Inventors: TANAKA AKIRA
• Application Number:
  US04/798,594
• Time in Patent Office: 713 Days
• US Class Current: 188/134
• CPC Class Codes: B60R 22/3405 of the non-rotary type
• CPC Class Codes: Y10T 74/2133 Pawls and ratchets
• CPC Class Codes: Y10T 74/2136 Pivoted pawls

Abstract

An elongated belt-locking retractor includes a support on which is mounted a pair of elongated toothed racks and a slide which reciprocates on the support between the racks. The slide has pawls which in an extended position mate with the racks but which are normally retracted against a stop by a spring. A cam for driving the pawls into the racks is mounted to the slide for motion with or motion relative to the slide depending on the differential rate of acceleration between the cam and the slide. A belt passes around the cam and acceleration of the belt accelerates the cam as the belt moves. If the rate of acceleration is less than a predetermined rate, the cam and the slide reciprocate as a unit allowing the belt to move freely. If the rate of acceleration is greater, the cam moves relative to the slide, driving the pawls into the racks to lock the slide and thereby lock the belt.

Claims

1. An elongated retractor for a restraint belt comprising a support, elongated rack means secured to the support, a slide, means mounting the slide on the support for reciprocal movement relative to the rack means, pawl means pivotally mounted to the slide for reciprocal movement therewith relative to the rack means and pivotal movement relative thereto into engagement with the rack means to releasably secure the slide to the rack means, biasing means normally holding the pawl means out of engagement with the rack means, cam means mounted on the slide for movement therewith and reciprocal movement relative thereto into engagement with the pawl means to move the pawl means into engagement with the rack means against the action of the holding means, relative movement control means for controlling said cam means and said slide to move as a unit on application of an acceleration to the cam means below a predetermined limit and also to permit said cam means to move relative to said slide on application of an acceleration to the cam means greater than said predetermined limit, and means for applying acceleration from a restraint belt to the cam means.

2. An elongated retractor for a restraint belt comprising a support, a pair of spaced elongated racks mounted to the support, a slide, means mounting the slide on the support for reciprocal movement relative to the racks, a pair of pawls pivoted to the slide for reciprocal movement therewith relative to the racks and pivotal movement relative thereto into engagement with a respective rack to releasably secure the slide to the racks, holding means normally holding the pawls out of engagement with the racks, cam means mounted to the slide for movement therewith and reciprocal movement relative thereto into engagement with the pawls to move the pawls into engagement with the racks against the action of the holding means, friction means for providing a frictional connection between said cam means and said slide to move said cam means and said slide as a unit on application of an acceleration to the cam means below a predetermined limit and also to permit said cam means to move relative to the slide on application of an acceleration greater than the predetermined limit, and means for applying acceleration from a restraint belt to the cam means.

3. A retractor as recited in claim 2 wherein gear means interconnect the pawls for movement of the other pawl upon movement of one pawl.

4. A retractor as recited in claim 2 wherein the cam means wedges the pawls oppositely into their respective racks.

5. An elongated retractor for a restraint belt comprising a support, a pair of elongated racks mounted to the support in a spaced relationship, a slide including a flat portion and runners engaging the support for reciprocal movement relative to the racks and for spacing the flat portion of the slide from the support, a pair of pawls pivotally mounted to the flat portion for reciprocal movement with the slide and swinging movement thereto into engagement with the respective rack to releasably secure the slide to the rack, spring means mounted between the pawls normally holding the pawls out of engagement with the rack, stop means mounted to the slide for positioning the pawls on the flat portion, a cam frictionally engaging the flat portion of the slide for causing movement therewith and also for permitting reciprocal movement relative thereto into engagement with the pawls to move the pawls into the racks against the action of the spring means, clamp means for clamping said cam and said slide to control the frictional engagement therebetween to move the cam and the slide as a unit upon the application of an acceleration to the cam belOw a predetermined limit and also to permit said cam to slide on the slide upon application of an acceleration greater than the predetermined limit to pivot the pawls, and means applying acceleration of the restraint belt to the cam means, said restraint belt passing under the slide, around the cam means and over the slide.

6. A retractor as recited in claim 5 wherein the clamp means comprises a slot in the cam fastening means through the slot clamping the cam to the slide, the slot being sufficiently long to allow the cam to move the pawls into engagement with their respective racks before the fastening means engages the end of the slot whereby the load of stopping the cam is taken by the pawls rather than by the fastening means.