JPH0131567Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a retractor for a seat belt, and relates to a retractor that can be used comfortably by relieving the feeling of pressure on the user's body when worn. The object of the present invention is to provide a structure that is simple in structure, reliable in operation, and in which the operating position of a pressure relief mechanism does not easily shift even if the wearer moves his or her body while wearing a seatbelt. It is.

The present invention will be explained with reference to the drawings. Reference numeral 1 denotes the main body of the retractor, which is composed of a bottom plate 2 and a pair of side plates 3 provided opposite to each other on both sides of the bottom plate 2. Side plate 3
A shaft 4 is rotatably supported via a bush 5, and a webbing 6 is wound around the shaft 4. One end of the shaft 4 protrudes from the side plate 3, and a slot 7 is formed at its tip. A rotary plate 8 is rotatably supported by the shaft 4, and has ratchet teeth 9 formed on its outer periphery. Further, a ring-shaped protrusion 10 is provided on the side surface of the rotary plate 8 facing the side plate 3, and a friction plate 11 is fitted on the outer periphery of the protrusion 10. The friction plate 11 is ring-shaped and has an outer diameter that is approximately the same as the outer diameter of the ratchet teeth 9 of the rotary plate 8. Large cam protrusion 12
A cam recess 13 having a diameter slightly smaller than the diameter of the bottom of the ratchet tooth 9 is formed in the center thereof, and a stopper piece 14 is provided protruding from a part of the outer periphery. The friction plate 11 is fitted loosely into the convex plate 10, and rotates together with the rotary plate 8 due to the frictional force of a friction spring 15.

Two protrusions 16, 1 are provided on the opposite surface of the rotating plate 8.
7, and first and second planetary gears 18 and 19, which are in mesh with each other, are rotatably supported by the projections 16 and 17, respectively. 20 is a gear integrally fixed to the shaft 4;
It is fixed to the shaft 4 using the slot 7. The gear 20 meshes with the first planetary gear 18.

A barrel 21 is rotatably supported on the shaft 4, and a spiral spring 22 is provided between the barrel 21 and the shaft 4 to apply a rotational force to the shaft 4 in the belt winding direction. There is. Also, on the side of the barrel 21 is a sun gear 24 having internal teeth 23.
are fixed together, and the internal teeth 23 thereof mesh with the second gear 19. Also that sun gear 2
4 protrudes outward to form a cam protrusion 25, and one edge of the cam protrusion forms a stopper edge 26.

Reference numeral 27 denotes a ratchet rotatably supported by the side plate 3, and a pawl 28 that engages with the ratchet teeth 9.
, and is constantly biased by a wire spring 29 in the direction of engagement with the ratchet teeth 9.

Reference numeral 30 denotes a casing, and stoppers 31 and 32 that come into contact with the stopper pieces 14 of the friction plate 11 are provided on the inner periphery of the casing. 33 is a stopper that comes into contact with the stopper edge 26 of the sun gear 24, and is fixed to the side plate 3.

Next, the operation of this retractor will be explained. Fourth
The figure is a schematic diagram showing the operation, and FIG. 4a shows a state in which the webbing 6 is wound around the retractor. In this state, the friction plate 11 is rotated clockwise, and the stopper piece 14 is in contact with the stopper 32. The pawl 28 of the ratchet 27 rests on the cam convex portion 12b and does not engage with the ratchet teeth 9 of the rotating plate 8. Further, the sun gear 24 rotates clockwise and is in contact with the stopper 33.

If you pull out the webbing 6 here, the shaft 4
rotates clockwise. Since the clockwise rotation of the sun gear 24 is stopped by the stopper 33, the first and second planetary gears 18 and 19 revolve counterclockwise around the gear 20 while rotating.
As a result, the rotating plate 8 rotates counterclockwise, and the friction plate 11 also rotates in the same direction. As a result, the pawl 28 of the ratchet 27 once sinks into the cam recess 13 of the friction plate 11, but since the direction of rotation of the rotary plate 8 is opposite to the direction of engagement of the ratchet teeth 9,
The pawl 28 is immediately pushed up and rides on the cam convex portion 12a. Then, as shown in Fig. 4b, the stopper piece 1
4 comes into contact with the stopper 31, and the rotation of the friction plate 11 is stopped. Thereafter, the rotary plate 8 continues to rotate.

Next, when the webbing 6 is pulled out to the required length and worn, and the excess webbing 6 is rolled into the retractor, the shaft 4 first rotates counterclockwise,
The first and second planetary gears 18 and 19 rotate around the gear 20 in a clockwise direction in the opposite direction to that described above. As a result, the rotating plate 8 and the friction plate 11 rotate clockwise, and the pawl 28 of the ratchet 27 sinks into the cam recess 13 of the friction plate 11 and engages with the ratchet teeth 9 as shown in FIG. 4c. match.
As a result, the rotation of the rotating plate 8 is stopped.

Webbing 6 is further entangled and shaft 4
further rotates, the rotating plate 8 cannot rotate clockwise, so the first and second planetary gears 18, 1
9 cannot revolve, only rotates on its own axis. This causes the sun gear 24 to rotate counterclockwise.
This situation is shown in FIG. 4d. Therefore, the rotational speed of the shaft 4 relative to the sun gear 24 decreases, and the spiral spring 22 causes the shaft 4 to rotate.
This reduces the winding force applied to the winding. Therefore, the winding force applied to the webbing is reduced, and the feeling of pressure on the user's body is reduced, so that the user can use the webbing comfortably without feeling pressured on his or her body.

Next, when the user releases the wearer and retracts the webbing 6 into the retractor, the shaft 4 and the sun gear 24 further rotate counterclockwise from the state shown in FIG. 4d. Then, the claw 2 is
8 is pushed up, and the engagement between the pawl 28 and the ratchet teeth 9 is released. Then, the sun gear 24 rapidly rotates clockwise due to the spring force of the spiral spring 22, and the first and second planetary gears 18, 19 revolve around the gear 20 while rotating, and the rotation plate 8 and friction The plate 11 rotates clockwise, the pawl 28 rides on the cam protrusion 12b, the stopper piece 14 contacts the stopper 32, and the rotation of the friction plate 11 is stopped, and the rotary plate 11 and the sun gear 24 continue to rotate. Subsequently, the stopper edge of the cam convex portion 25 comes into contact with the stopper 33, thereby stopping their rotation and returning to the state shown in FIG. 4a. After that, the entire winding force of the spiral spring 22 acts on the shaft 4, and the shaft is rotated with a large force, so that the webbing 6 can be wound up.

In the present invention, when the seat belt is worn, the winding force applied to the webbing 6 is reduced, and the tension of the webbing is reduced, so that the user does not feel excessive pressure on his or her body.
Can be used comfortably. On the other hand webbing 6
When the webbing 6 is wound into the retractor, the winding force becomes large, and it becomes possible to wind the webbing 6 sufficiently and completely. Furthermore, according to the present invention, after the webbing 6 is pulled out and put on, and the excess webbing 6 is rolled up into the retractor, the webbing 6 can be worn not only when the webbing is normally worn, but also when the webbing 6 is pulled out by moving the body. However, the tension applied to the webbing 6 is small, preventing a feeling of pressure.

Furthermore, in the present invention, the pawl 28 is operated by the sun gear 24, which rotates while being decelerated from the rotation of the shaft 4, so the winding force applied to the webbing 6 is reduced over a wide range, and the user does not have to move his/her body significantly. Also, the winding force will not increase inadvertently.

Furthermore, in the present invention, gear groups 20, 18, 1
Since the retractors 9 and 23 are arranged on the same plane, the retractor can have a thin and compact mechanical part.

[Brief explanation of the drawing]

FIG. 1 is a central longitudinal cross-sectional view of the main part of the retractor of the present invention, and FIGS. 2 and 3 are cross-sectional views of FIG. 1. FIG. 4 is a schematic diagram showing the operation of the present invention. 1...Main body, 3...Side plate, 4...Shaft, 8
... Rotating plate, 9 ... Ratchet tooth, 11 ... Friction plate, 13 ... Cam recess, 18 ... First planet gear, 19 ... Second planet gear, 20 ... Gear, 2
1... Barrel box, 22... Spring means, 23... Internal teeth,
24...Sun gear, 25...Cam protrusion, 27...
Ratchet.

Claims (1)

[Scope of utility model registration request] A shaft 4 rotatably supported by a pair of opposing side plates 3 of the main body 1, a gear 20 fixed to the shaft 4, and a gear 20 rotatably fitted to the shaft 4 and having ratchet teeth 9 on its outer periphery. A friction plate 11 that is fitted onto the rotary plate 8 and rotates together with the rotary plate 8 due to frictional force, has a limited rotation range with respect to the main body 1, and has a cam recess 13 on the outer periphery.
a first planetary gear 18 rotatably supported by the rotating plate 8 and meshing with the gear 20; and a first planetary gear 18 rotatably supported by the rotating plate 8 and meshing with the first planetary gear 18. It has a second planetary gear 19 and internal teeth 23 that are rotatably supported on the shaft 4 and mesh with the second planetary gear 19, and have a cam recess 25 on the outer periphery and have a rotation range relative to the main body 1. a limited sun gear 24; a barrel 21 integrally fixed to the sun gear 24;
and a spring means 22 mounted between the shaft 4 and the shaft 4 so as to apply a rotational force to the shaft 4 in the belt winding direction; A seat belt retractor having a ratchet 27 biased toward engagement.