Low profile web adjuster

Abstract: A low profile web adjuster for securing a web. A seat includes a harness, one end of which (34) extends through a web adjuster mounted to the seat. A pivot cam (144) on the adjuster is operable to lockingly engage one end of the harness. In the preferred embodiment, the cam (144) is moved by pulling a control member (164) having a pair of arms pivotally mounted to the cam member at a location to force the cam member apart from the web (135). Under normal loading, the cam member contacts and holds the web (34) against the base wall (141) of the adjuster and under high loading also holds the web against an upraised rib on the base wall (171).

Description: BACKGROUND OF THE INVENTION Field of the Invention: This invention is in the field of fasteners for securing webs and belts. Description of the Prior Art: Recently enacted laws require seats within automobiles for restraining a child or infant. Typically, the seats include a harness which is releasably securable around the child with the harness passing over the shoulders and having a front end releasably locked to a buckle or similar fastening device. Such a seat with harness is shown in U. S. Patent 4,660,889 issued to Indiana Mills & Manufacturing, Inc. The harness passing over the child's shoulders and through the seat has an opposite end frictionally engaged by a web adjuster mounted to the seat. The web adjuster has a pivotally mounted cam member which may be released to facilitate sizing of the harness relative to the child. Such web adjusters are also shown in U. S. Design Patents 296,678 and 303,232 assigned to Indiana Mills & Manufacturing, Inc. Other web adjusters incorporating pivotally mounted cams with gripping surfaces for holding webs are shown in the U.S. Patents 3,434,186 issued to Rennert and 3,872,550 issued to Yang. The aforementioned web adjusters include an outwardly extending handle allowing the user to pivot the cam member for releasing the web relative to the adjuster. In U. S. Patent 4,679,852 assigned to Indiana Mills & Manufacturing, Inc., on which the preamble of the claim is based, a rotatable rod mounted to the child's seat extends through the web adjuster handle to allow the user to rotate the rod and thereby pivot the web adjuster handle. I have provided a web adjuster having a more compact means for operating the pivotally mounted cam member of the web adjuster. Disclosed herein is such a web adjuster having control means to pull for pivoting and thereby releasing the cam member. In U.S. Patent 4,716,630 the web adjuster includes a rib on the base with a cam member forcing a rope or web simultaneously against the base and rib to increase the area of contact. By increasing the area of contact, it becomes exceptionally difficult to release the cam member from the web and therefore what is needed is an adjuster which provides two stages of locking. In the first stage of web locking, the cam member forces the web against the base requiring minimum release force whereas in a second stage of web locking which may occur in a crash situation, the cam member is operable to further rotate forcing the web against the base and an upraised rib requiring maximum release force. SUMMARY OF THE INVENTION The embodiment of the present invention includes a child restraining device for mounting in a vehicle wherein the device having a child support upon which the child may be supported and a harness movably mounted to said child support and including a restraining portion positionable against the child with first lock means thereon, said harness including a web affixed thereto being located beneath said support with said web extending forwardly through said support. A second lock means is mounted to said support and engageable with said first lock means to secure said harness to said support. A web adjuster mounted to the support with the adjuster including cam means with teeth frictionally receiving said web being operable to hold said web once said web is pulled manually in a tightening direction through said adjuster to tighten said harness and also being operable to release said web to loosen said harness upon manual operation of said adjuster. The adjuster including a frame with a base having a rib formed thereon and a pair of upstanding walls secured thereto with said cam means including a pivot axis. The cam means having a cam member pivotally mounted to said walls. The cam member is normally located in a web engageable position holding the web against the base, said cam member being movable from said web engageable position to an increased gripping position whereat said cam member holds said web against said rib and being also movable from either of both said positions to a release position allowing said web to move relative to said frame, said adjuster further including control means engaged with said cam member operable to move said cam member to said release position. The teeth of the cam member normally holding said web against said base through a first angle of contact while under said normal web loading but holding said web against said base and said rib through a second angle of contact greater than said first angle increasing the holding thereof while under an abnormal high web loading. The control means includes a pair of spaced apart arms pivotally engaged with the cam member at a location between the pivot axis and the teeth to pivot the cam member as the control means move, said control means including a rod and a pull strap mounted thereto with said rod joining said arms together, said pull strap being pullable away from said pivot axis and said rib in said tightening direction pivoting said cam member and moving said teeth apart from said web allowing said web to be moved in a direction opposite said tightening direction to loosen said harness. It is an object of the present invention to provide a new and improved web adjuster. A further object of the present invention is to provide a web adjuster having a low profile. Yet another object of the present invention is to provide a low profile web adjuster. An additional object of the present application is to provide a web adjuster which will increase the web holding force during abnormal high loading. Related objects and advantages of the present invention will be apparent from the following description. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective fragmentary view of a seat having the adjuster incorporating the present invention. FIG. 2 is an enlarged top view of the web adjuster mounted to the seat of FIG. 1 with the outer housing removed. FIG. 3 is a cross-sectional view taken along the line 3-3 of FIG. 2 and viewed in the direction of the arrows. FIG. 4 is a cross sectional view taken along tile line 4-4 of FIG. 2 and viewed in the direction of the arrows showing the adjuster in the locked position under normal loads. FIG. 5 is the same view as FIG. 4 only showing the adjuster in the locked position under abnormal high loads. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularly to FIG. 1, there is shown a seat 20 having a back portion 21 and seat portion 22 integrally connected together. A harness 23 is mounted to the seat and is designed to adjust to the size of the child placed on the seat. A variety of different types of harnesses may be installed onto the seat. In FIG. 1, a 5 point harness is depicted. As such, harness 23 includes two webs 24 and 25 having respectively first ends 26 and 27 fixedly fastened to the seat with both webs slidably extending respectively through a pair of conventional separate tongues 28 and 29 releasably lockable to a conventional seat belt buckle 30. Buckle 30 is secured to strap 31 having a strap end 32 fixedly secured to the seat. Webs 24 and 25 extend slidably through slots provided in back portion 21 of the seat with the webs then extending rearwardly of the seat being fastened to a bar 33. The bar is also fastened to a third web 34 extending forwardly through a slot 35 formed in seat portion 22. Web 34 then extends releasably through a web adjuster 140 fastened to the seat. Operation of the web adjuster allows web 34 to be loosened or tightened which in turn results in the loosening or tightening of harness 23. Many variations are contemplated and included in the present invention. For example, the web adjuster is shown in combination with a 5 point harness although the web adjuster will work equally well with other types of harnesses so long as the web adjuster is operable to loosen or tighten the harness. The web adjuster is shown in FIG. 2 through FIG. 5. Web adjuster 140 includes a frame having a pair of upstanding walls 142 and 143 integrally joined to a base wall 141 which extends generally horizontal and is affixed to the horizontal seat portion of the seat. A cam member 144 is pivotally mounted to walls 142 and 143. Pivotally mounted by a pin 45 to and between walls 142 and 143 is a cam member 144. Cam member 144 (FIG. 3) includes a through hole 46 within which is positioned a helical spring 47 and pin 45. The pin extends centrally through the helical spring and has a slot 48 at one end to receive one end 49 of the spring with the opposite end 50 of the spring extending into a hole 51 provided in the cam member. The helical spring is installed with the opposite ends in slot 48 and hole 51 so that the plurality of friction ridges 152 (FIG. 4) provided on the outer surface of the cam member are forced against web 34 trapping the web between the cam member and base wall 141. Wall 143 includes an aperture through which end 54 of the pin extends. The aperture is restricted preventing rotational movement of the pin. The opposite end of the pin includes a groove 56 located immediately inward of wall 142 when the pin is installed to the adjuster. A conventional C-shaped clamp 57 is mounted within the groove preventing the pin from disengaging walls 142 and 143. Web 34 extends through a slot 35 (FIG. 1) formed in seat support 22 and is attached by means of bar 33 to the harness. The free end of the web extends through a hole in the web adjuster housing and lies against the forward portion of the seat. The spring is operable to normally force cam member 144 in the counterclockwise direction opposite of arrow 178 (FIG.4) thereby causing the friction engaging surface of the cam formed by teeth 152 to engage web 34 preventing movement of the web in the web release direction which is opposite of arrow 173. At the same time, the web may be grasped and pulled in the direction of arrow 173 to tighten the harness. Web adjuster 140 has a pull control 162 (FIG. 2). Pull control 162 has a pair of arms 163 and 164 having inwardly turned distal ends 134 and 135 projecting into holes provided on the opposite outwardly facing ends of cam 144. For example, arm 164 has an inwardly turned distal end 135 projecting into hole 168 (FIG. 4) provided on end 189 of the cam element. A rod 167 is integrally joined to and between arms 164 and 163 with a fabric strap 170 extending around rod 167. One end 191 of strap 170 is secured by stitching or other suitable means to the main body of the strap with the opposite end of the strap extending freely away from the web adjuster. Thus,strap 170 may be pulled in the direction of arrow 173 thereby causing clockwise rotation 178 of cam 144 as viewed in FIG. 4 forcing the friction teeth 152 to disengage web 34 allowing the web to be moved in the direction opposite of arrow 173 thereby loosening the harness. Release of strap 170 allows the helical spring to rotate the cam in a counter clockwise direction as viewed in FIG. 4 thereby engaging web 34 and preventing further loosening of the harness. Web 34 may be moved in the direction of arrow 173 to tighten the harness even though teeth 152 are engaged with the web. Notably, fabric strap 170 may be moved in the direction of arrow 173 which is the same direction that web 34 is moved when tightening the harness. FIG. 4 illustrates the adjuster in the locked position under normal loads. The bottom wall 141 of the bracket includes an upraised rib 190 located between the pivot axis of cam member 144 and the aft end 174 of the bracket. Rib 190 is intregal with bottom wall 141 and is joined thereto by means of an upwardly sloping front wall 171 and an upwardly sloping back wall 172. The rib extends across the width of wall 141 between upraised walls 142 and 143 and has opposite ends terminating inwardly of the upstanding walls 142 and 143. Thus, the base wall 141 is flat between the upstanding walls and the opposite ends of the rib. In one embodiment, the rib terminated approximately 1/4 inch inwardly of upstanding walls 142 and 143. Under normal loading, teeth 152 engage belt 134 and force the belt against the upwardly facing surface of bottom wall 141 at a location between the front end 183 of the bracket and the upwardly sloping wall 171 of rib 190. The upwardly facing flat surface of wall 141 is located further from the pivot axis of cam 144 than the upwardly facing surface of wall 171. The distance from the teeth 152 to the pivot axis of the cam is such that the cam member under normal loading positions teeth 152 atop the upwardly facing surface of wall 141 apart from the upwardly facing surface of wall 171. That is, under normal locked conditions, the teeth of the cam are not located adjacent wall 171 and thus the belt is not lockingly forced thereagainst. On the other hand, under abnormal high loading such as experienced in a crash or under emergency conditions, the passenger is forced against belt 34 thereby pulling the belt in the direction opposite of arrow 173 forcing the cam to pivot further in a counterclockwise direction as viewed in FIG. 4 thereby forcing the teeth atop the upwardly facing surface of wall 171 holding the belt between wall 171 and the cam member. To unlock the adjuster, tab 170 is then pulled in the direction of arrow 173. FIG. 5 illustrates the adjuster in the locked position under abnormal high loads. Such loads occur in a crash or other emergency situation whereby cam member 144 pivots an additional amount in the counterclockwise direction as viewed from FIG. 4-FIG. 5 thereby positioning teeth 152 against the upwardly facing surface of wall 171 of rib 190. Belt 34 is thereby forced against and locked to rib 190. Teeth 152 while forcing the belt against wall 171 also force the belt against the upwardly facing flat surface of wall 141 immediately in front of wall 171 thereby not only increasing the area of contact between the belt, teeth and wall but also most importantly increasing the angle of contact around the pivot axis of cam 144 existing between the belt, teeth, wall 141 and wall 171. For example, the angle 180 (FIG. 4) of contact a round the cam pivot axis between the belt, teeth and wall 141 increases to angle 181 (FIG. 5) under high loading with teeth 152 forcing the belt against wall 141 and wall 171. In addition to providing additional locking of the belt, the rib is operable to prevent the bottom wall from bowing under extreme loads. Without such a rib, the bottom wall bows under high loading thereby forcing the wall apart from the teeth and belt considerably reducing the locking ability of the adjuster. The rib is particularly advantageous in that the area of contact between the belt, rib and bottom wall is across substantially the entire width of the adjuster thereby preventing the belt from cocking or wiggling loose. While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiments have been shown and described.

Claims: A child restraining device for mounting in a vehicle wherein the device having: a child support (20) upon which the child may be supported; a harness (23) movably mounted to said child support (20) and including a restraining portion (24-25) positionable against the child with first lock means (28-29) thereon, said harness (23) including a web (34) affixed thereto being located beneath said support with said web extending forwardly through said support; second lock means (30) mounted to said support (20) and engageable with said first lock means (28-29) to secure said harness to said support; and, a web adjuster (140) mounted to said support (20) with said adjuster including cam means with teeth (152) frictionally receiving said web (34) being operable to hold said web once said web is pulled manually in a tightening direction (173) through said adjuster (140) to tighten said harness and also being operable to release said web (34) to loosen said harness upon manual operation of said adjuster, said adjuster including a frame with a base (141) having a rib (190) formed thereon and a pair of upstanding walls (142-143) secured thereto with said cam means including a pivot axis, said cam means having a cam member (144) pivotally mounted to said walls (142-143), said cam member (144) being normally located in a web engageable position holding said web (34) against said base (141), said cam member being movable from said web engageable position to an increased gripping position whereat said cam member (144) holds said web (34) against said rib (190) and being also movable from either of both said positions to a release position allowing said web (34) to move relative to said frame, said adjuster further including control means engaged with said cam member (144) operable to move said cam member (144) to said release position, said teeth (152) of said cam member (144) normally holding said web (34) against said base (141) through a first angle of contact (180) while under said normal web loading but holding said web against said base and said rib through a second angle of contact (181) greater than said first angle (180) increasing the holding thereof while under an abnormal high web loading, wherein the device is characterized in that said control means includes a pair of spaced apart arms (164) pivotally engaged with said cam member (141) at a location between said pivot axis and said teeth (152) to pivot said cam member (144) as said control means move, said control means including a rod (167) and a pull strap (170) mounted thereto with said rod (167) joining said arms (164) together, said pull strap being pullable away from said pivot axis and said rib (190) in said tightening direction (173) pivoting said cam member (144) and moving said teeth (152) apart from said web (34) allowing said web to be moved in a direction opposite said tightening direction to loosen said harness (23).

Inventors: LEE DAVID J, LEE, DAVID J.
Applicants: INDIANA MILLS & MFG, INDIANA MILLS & MANUFACTURING, INC.
Application year: 1991
Main classification: B60R22
IPC codes: A44B11, B60R22