GB2026308A - A safety belt reel apparatus - Google Patents

Abstract

A safety belt reel apparatus for a vehicle, comprises a reel around which a belt is arranged to be wound and unwound, a control disc (32) freely rotatable relative to the reel and provided with teeth (31), locking means actuable by the control disc (32), a trigger mechanism (21), responsive to a predetermined acceleration or deceleration of the vehicle to actuate the control disc (32), a cam disc (37) mounted co- axially with the central disc (32) and rotatably displaceable in either sense from a predetermined position relative to the control disc (32) and provided with a cam (46) for actuating the locking means, and spring means (40) so disposed as to urge the cam disc (37) to a predetermined position against said rotation thereof. (Fig. 3). <IMAGE>

Description

SPECIFICATION Safety belt reel apparatus The present invention relates to a safety belt reel apparatus.

In known belt reel apparatuses a control disc initiates the actuation of a locking device, to lock the reel apparatus in such a manner that the control disc is arrested in the case of vehicle retardations, for example through a mechanical trigger mechanism for example a so-called ball sensor. During subsequent belt withdrawal, the belt reel rotates. Great value is attached to this rotation being terminated by the locking device becoming effective after the shortest possible angular travel. For this purpose, it is necessary that the control disc can execute a motion relative to a predetermined initial setting; for example the control disc being under the effect of a spring and being resiliently deflectable in only one direction, whereafter it again returns into the initial position.Safety belt reel apparatuses of that kind are fastened in mirror-image arrangement at the mutually opposite vehicle frame (incorporation at the right and left) so that control discs with different spring suspension would be required in the case of the last described solution, whereby inter alia mass production of safety belt reel apparatuses of that kind is made more difficult.

According to the present invention there is provided a safety belt reel apparatus for a vehicle, comprising a reel around which a belt is arranged to be wound and unwound, a control disc freely rotatable relative to the reel and provided with teeth, locking means actuable by the control disc, a trigger mechanism responsive to a predetermined acceleration or deceleration of the vehicle to actuate the control disc, a cam disc mounted co-axially with the control disc and rotatably displaceable in either sense from a predetermined position relative to the control disc and provided with a cam for actuating the locking means, and spring means so disposed as to urge the cam disc to the predetermined position.

The teeth may be disposed at the outer periphery of the control disc.

The control disc may be provided with a hub journalling the cam disc.

The hub may be provided with an annular groove and the cam disc may be provided with a projection engaging in the groove to locate the cam disc axially relative to the control disc.

The cam disc may be provided with recess means and the control disc may be provided with recess means aligned with the recess means of the can disc to together provide arcuate channel means in which is disposed the spring means, the cam disc and the control disc each being provided with abutment means, the spring means bearing against the abutment means to urge the cam disc to the predetermined position.

The channel means may comprise a single circularly arcuate channel and the abutment means may comprise end walls of the channel means.

The channel may extend around substantially the entire periphery of the cam disc.

The channel means may comprise two circularly arcuate channels circumferentially spaced by wall means of the abutment means, a respective spring being disposed in each channel and each having an end which bears against the wall means.

The cam disc may be provided with abutment means and the control disc may be provided with abutment means aligned with the abutment means of the cam disc when in the predetermined position, the spring means comprising a spring mounted around the hub and having free limbs which bear against the abutment means to urge the cam disc to the predetermined position.

The cam disc may be provided with abutment means and the control disc may be provided with abutment means aligned with the abutment means of the cam disc when in predetermined position, the spring means comprising a coil spring mounted to the hub and having free limbs which bear against the abutment means to urge the cam disc to the predetermined position.

Embodiments of the present invention will now now be more particularly described by way of example and with reference to the accompanying drawings in which: Figures 1 and 2 show in side view and sectional view, an illustration of a safety belt reel apparatus, Figures 3 and 4 show a first embodiment of a control disc of a safety belt reel apparatus and respectively in two different settings of actuation, Figures 5 and 6 show two alternative refinements of the control disc shown in Figs. 3 and 4, Figures 7 and 8 show a second embodiment of a control disc respectively in two different settings of actuation, Figure 9 shows in schematic illustration, a third embodiment of a control disc, Figures 10 and ii shows schematic illustration, a fourth and fifth embodiment respectively of the control disc, and Figure 12 shows a detail of Fig. 11.

Referring to Figs. 1 and 2 a housing, of a safety belt reel apparatus comprises rigid material and has two side cheeks 2 as well as a cross member 3. Rotatably journalled in the side cheeks 2, of which only one is illustrated in the Figs. is the belt reel 4, which projects beyond the side cheek 2 and has an end projection 5 as well as a thin cylindrical spigot 6. 6. The safety belt wound on the belt reel 4 is designated by 7. A toothed locking rim 9 with internal locking teeth 10 is fastened to the external surface of the side cheek 2. A twolimbed locking pawl 11 is pivotably journalled on a bearing pin 1 2 at the end projection 5 of the belt reel 4 and eccentrically to the belt reel, wherein the locking edge, at the top in Fig. 1, of this locking pawl is urged by a spring 1 3 towards the belt reel.For the sake of clarity, one control disc 14 is shown only in dashed lines and one inertia disc 1 5 connected with the control disc is not shown in Fig. 1. The inertia disc 1 5 has a bearing projection 16 with a bearing bore, the bearing projection integrally carrying a control cam 18. The control disc 14, which is provided with an appropriate bearing opening, is shapelockingly mounted onto bearing projection 1 6 and control cam 1 8. The unit of control disc and inertia disc is journalled on the spigot 6 of the belt reel 4 to be rotatable relative to the belt reel 4. The control disc 14 possesses raylike narrow control teeth 20 having the same pitch and number of teeth as the locking teeth 10.Generally designated by 21 is a trigger mechanism, which has the shape of a so-called ball sensor and which comprises a base plate 22 fastened to the housing of the automatic reel apparatus and having a centering bore 23, of a ball 24 as well as of a pivotable control lever 25 bearing lightly against the ball 24. The trigger mechanism 21 is actuated on an excessive retardation of the vehicle. In this case, the ball 24 is displaced outside the region of the centering bore 23 with the consequence that the control lever 25 is urged upwardly. Thereby, the control disc 14 is stopped. The safety belt is still unreeled slightly until, in consequence of the meanwhile arisen relative motion between belt reel 4 and control disc 14, the control cam 18 runs up at the inside surface of the locking pawl 11 and the locking pawl presses against the locking toothing 10.

Figs. 3, 4 and 5 show a control unit 30 comprising a flat control disc 32, which is provided with control teeth 31 arranged at its outer periphery and which has a bearing hub 33 with concentric annular groove 34 as well as a concentric collar 35, while a circularly arcuate recess 36 is provided in a part of the collar 35. As Figs. 3 and 5 show, a flat cam disc 37 is journalled to be freely rotatable on the bearihg hub 33. The cam disc has a resilient lug 38, which on plugging of the cam disc on to the bearing hub is resiliently hookable into the concentric annular groove 34, whereafer the cam disc is axially secured.

The cam disc 37 has a circularly arcuate recess 39, while the recesses 36 and 39, which are stepped radially apart, of control disc and cam disc form a closed receiving channel 36/39 for a compression spring 40.

The shoulders, bounding the circular arc of the receiving channel at both ends, of the recesses 36 and 39 form radially mutually aligned abutments 41, 42 and 43, 44 which are tensioned against each other by both the ends of the spring 40 disposed in the receiving channel 36/39. When the trigger mechanism 21 becomes effective, by getting into a locking setting, the control disc 32 is locked at the control teeth 31. The starting or initial setting is shown in Fig. 3, while Fig. 4 shows the setting, in which belt has already been drawn off and the blocking of the automatic reel apparatus i.e. the blocking of the belt reel is terminated.The abutments 41 and 42 or 43 and 44 of control disc and cam disc have in this case displaced relative to one another in a clockwise sense through an angle 'a', while on being relieved the tensioned spring 40 brings the mutually associated abutments again into alignment (initial setting). During actuation of the control unit 30, the locking pawl designated by 11 in the Figs. 1 and 2 was displaced into the locking setting by means of the control cam 46 of the cam disc 37. Deflection of the cam disc 37 in counter clockwise-sense is also possible by the arrangement of the spring 40, whereafter the abutments again become aligned with one another.

The embodiment shown in Fig. 6 differs from that shown in Figs. 3 to 5 in that control disc 32' and cam disc 37' are provided with axially opening recesses 36' and 39' as well as with axially mutually aligned abutments for the spring 40'.

In the embodiment shown in Figs. 7 and 8, a circularly arcuate receiving channel 51 and 52 for the reception of a respective spring 53 is disposed to both sides of an abutment 47 and 48 of control disc 49 and cam disc 50, wherein the springs 53 bear against the radi telly mutually aligned abutments 47 and 48 as well as the other end against the corresponding shoulders 54, bounding the receiving channels, of the cam disc 50. Relative motion of control disc and cam disc, for example through the angle 'a', in a clockwise sense as well as in counter-clockwise sense is possible as Fig. 8 shows. The abutments 47 and 48 are after removal of load again urged back into the aligned or initial setting.

Disposed in control disc 55 and cam disc 56 in the embodiment shown in Fig. 9 are annular recesses which form an annular receiving channel 57 with the exception of abutments 58 and 59, radially aligned with one another and arranged in the region of the receiving channel 57, of control disc and cam disc. The spring ends of a single annularly shaped spring 60 bear against these abutments.

In the embodiment shown in Fig. 10, a control disc 61 has an abutment 63 projecting into a recessed hollow space 62 of the control disc, while the cam disc 64, co-axial and co-operating with the control disc, has an abutment 65 facing the abutment 63. Jour nalled on a hub part or on the outer periphery of the cam disc 64 is a shaped spring 66 with two radially projecting free spring limbs 66' and 66" which bear against the radially mutu ally aligned abutments 63 and 65 and tension them against one another. Relative motion in both rotational directions is possible also here, while the setting of actuation of the cam disc after a relative motion is indicated by chain dotted lines.

In the embodiment shown in Figs. 11 and 12, in place of a shaped spring shown in Fig.

10, a coil spring 67 shown in detail in Fig.

1 2 is journalled by several spring turns on a hub part of the cam disc 68, while the freely projecting spring limbs 67' and 67" tension the abutments 69 and 70 of cam disc 68 and control disc 71 against one another. The deflected setting of the cam disc or of the abutment 70 of the cam disc is also indicated.

An advantage of the above described em bodiments is that a single reel type can be employed for incorporation at the right and at the left since the control discs are resiliently deflectable each time in both possible directions of rotation and on being relieved again automatically return into the initial setting.

Also the cam disc can during assembly be clipped effortlessly on the bearing hub of the control disc so that no special abutment elements are necessary for axial securing.

Claims (16)

1. A safety belt reel apparatus for a vehicle, comprising a reel around which a belt is arranged to be wound and unwound, a control disc freely rotatable relative to the reel and provided with teeth, locking means actuable by the control disc, a trigger mechanism responsive to a predetermined acceleration or deceleration of the vehicle to actuate the control disc, a cam disc mounted co-axially with the control disc and rotatably displaceable in either sense from a predetermined position relative to the control disc and provided with a cam for actuating the locking means, and spring means so disposed as to urge the cam disc to the predetermined position.

2. An apparatus as claimed in claim 1, wherein the teeth are disposed at the outer periphery of the control disc.

3. An apparatus as claimed in either claim 1 or claim 2, wherein the control disc is provided with a hub journalling the cam disc.

4. An apparatus as claimed in claim 3, wherein the hub is provided with an annular groove and the cam disc is provided with a projection engaging in the groove to locate the cam disc axially relative to the control disc.

5. An apparatus as claimed in any one of the preceding claims, wherein the cam disc is provided with recess means of the cam disc to together provide arcuate channel means in which is disposed the spring means, the cam disc and the control disc each being provided with abutment means, the spring means bearing against the abutment means to urge the cam disc to the predetermined position.

6. An apparatus as claimed in claim 5, the channel means comprising a single circularly arcuate channel and the abutment means comprising end walls of the channel means.

7. An apparatus as claimed in claim 6, wherein the channel extends around substantially the entire periphery of the cam disc.

8. An apparatus as claimed in claim 5, the channel means comprising two circularly arcuate channels circumferentially spaced by wall means of the abutment means, a repective spring being disposed in each channel and each having an end which bears against the wall means.

9. An apparatus as claimed in either claim 3 or claim 4, wherein the cam disc is provided with abutment means and the control disc is provided with abutment means aligned with the abutment means of the cam disc when in the predetermined position, the spring means comprising a spring mounted around the hub and having free limbs which bear against the abutment means to urge the cam disc to the predetermined position.

1 0. An apparatus as claimed in either claim 3 or claim 4, wherein the cam disc is provided with abutment means and the control disc is provided with abutment means aligned with the abutment means of the cam disc when in predetermined position, the spring means comprising a coil spring mounted to the hub and having free limbs which bear against the abutment means to urge the cam disc to the predetermined position.

11. An safety belt apparatus substantially as herinbefore described with reference to Figs. 1 and 4 of the accompanying drawings.

1 2. An apparatus as claimed in claim 11 and modified substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.

1 3. An apparatus as claimed in claim 11 and modified substantially as herein before with reference to Fig. 6 of the accompanying drawings.

14. An apparatus as claimed in claim 11 and modified substantially as herein before described with reference to Figs. 7 and 8 of the accompanying drawings.

1 5. An apparatus as claimed in claim 11 and modified substantially as hereinbefore described with reference to Fig. 9 of the accompanying drawings.

16. An apparatus as claimed in claim 11 and modified substantially as herein before described with reference to Fig. 10 of the accompanying drawings.

1 7. An apparatus as claimed in claim 11 and modified substantially as hereinbefore described with reference to Figs. 11 and 1 2 of the accompanying drawings.