JPH04116031U - spiral spring suspension system - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the outer end of the spiral spring for retracting webbing stored in the storage case of the retractor of a seat belt device from breaking or coming off from the attachment part due to repeated use. prevent. [Structure] A protrusion 16b having a substantially teardrop-shaped planar shape is protruded from the inner bottom surface of the case that houses the spiral springs 14 and 18, and a groove 16f is formed approximately in the center of the protrusion 16b.
Insert the outer ends 14c, 18c of the spiral springs 14, 18 into the spiral springs 14, 18, and wrap the protrusion 16b at least twice to form the tapered part 16.
c, and is wound from the tapered part 16c to the inner end.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to a suspension system for a spiral spring, and in particular, the outer end of the spiral spring is Suspension to prevent the spring from breaking or coming off from the fixed part when fixed to the base. It is related to the device.

0002

[Conventional technology]

In general, there are many devices that use spiral springs, but in particular they are used in vehicle safety belt devices. is a winding device that rotates a reel to wind up webbing (seat belt). The retractor is provided with a spiral spring that constantly urges the shaft to rotate.

0003 By the way, a spiral spring is made by winding a thin strip of metal into a spring shape. Attach the shaft on the biased side, such as a take-up shaft, to the end, and attach the outer end to the stationary side, such as a storage case. Each stays attached. To secure the outer end, use a ratchet wheel as shown in Figure 6. A dovetail-shaped protrusion 51 is provided on the inner bottom surface of the storage case 50 that also serves as a storage case. The outer end of the spiral spring 54 is engaged with the end 53 in the recess 52 formed at the rear of the spiral spring 54. 56 was wound twice.

0004

[Problem that the idea aims to solve]

However, according to the above-mentioned conventional spiral spring suspension device, the spiral spring 54 When expanded and contracted, the outer end portion 56 faces the protrusion 51 as shown by the imaginary line in FIG. from a state in which they are substantially orthogonal to a state in which they substantially overlap with a tangent to the arcuate portion 57 of the protrusion 51 However, the contact point C with the protrusion 51 remains almost unchanged, and the contact point C with the projection 51 remains constant. Since there is a bending force applied to the portion C, the outer end portion 56 is likely to be cut off. , durability may be reduced.

[0005] Therefore, this invention was made for the purpose of eliminating the above-mentioned disadvantages.

[0006]

[Means to solve the problem]

The suspension device for the spiral spring according to this invention is located at the inner bottom of the case that houses the spiral spring. A protrusion having a planar shape approximately in the shape of a teardrop is provided protrudingly on the surface, and a groove is formed approximately in the center of the protrusion, Insert the outer end of the spiral spring into the groove until it reaches the tapered part, and from the tapered part through the rear part. The spiral reaches the tapered part again and is wound tightly from the tapered part to the inner end. The tangent line of the spring and the tangent line of the arc portion are arranged so that they overlap in a straight line. Features.

[0007]

[Effect]

According to this invention having the above configuration, the spiral spring expands and contracts, and its diameter decreases and Even when expanded, the outer end of the spiral spring always remains in approximately constant contact with the protrusion to which it is attached. Since they touch at an angle, the amount of deformation at the outer edge is almost constant, and the bending force is applied to the outer edge. I won't give it.

[0008]

【Example】

Next, an embodiment of this invention will be described based on the drawings. As shown in Figures 1 to 3 Then, the winding shaft 2 of the seat belt winding device main body 35 is inserted through the shaft hole 1a drilled in the base plate 1. is made to protrude, and the first gear 3 is fitted onto the winding shaft 2. meshes with this gear 3 The shaft 4a of the second gear 4 is rotatably supported in the shaft hole 1f drilled in the substrate 1 (see Fig. 3). ), the gear 4 is integrally formed with a shaft portion 5, and the shaft portion 5 has an oval cut at the end. A surface roller mounting portion 6 is formed. The roller mounting part 6 has a shaft in its center. A hole 7 is formed in the axial direction, and grooves 8 are formed in the axial direction facing each other in the diametrical direction. 8 is formed, and protrusions 9, 9 are formed on the outer peripheral surface of the circular arc portion.

[0009] A third gear that meshes with the second gear 4 and is made of the same gear as the first gear 3 The gears 3a, 3a are placed at the remaining vertices of an equilateral triangle with the winding shaft 2 as the apex. They are each rotatably supported by shafts 1b, 1b protruding from the substrate 1. And this An internal gear 10 (see FIG. 2 and (see FIG. 3) is loosely fitted onto the shaft portion 5. Each of the inner tooth portion 10a and the gears 4, 3, 3a The tooth ratio is set to 3:1.

0010 The internal gear 10 is a cylindrical body with a substantially convex cross section, and has a shaft portion with a larger diameter than the winding shaft 2. 11, and a shaft hole 12 into which the shaft portion 5 is loosely fitted is bored. The shaft portion 11 has a notch that locks the inner end portion 14a of the main winding spring 14 made of a spiral spring. It has a built-in part 13,13. This main take-up spring 14 and the sub-take-up spring 18, which will be described later, A ratchet with an H-shaped cross section that has barrel chambers 15 and 15a (see Figure 3) for storing them respectively. A wheel 16 is loosely fitted onto the shaft portion 5, and the ratchet wheel 16 has ratchet teeth 1 on its outer peripheral surface. 7, and the other body chamber 15a of the ratchet wheel 16 has an auxiliary winding made of a spiral spring. The springs 18 are respectively housed.

[0011] The outer ends 14c and 18c of the main take-up spring 14 and the sub-take-up spring 18 are respectively Locked to spring hanging protrusions 16b, 16b formed on the inner peripheral edge of the barrel chambers 15, 15a. be done. Further, the inner end portion 18a of the sub-winding spring 18 is attached to the roller of the shaft portion 5. It is locked in either of the locking grooves 19a of the roller 19 that fits in the The take-up spring 14 and the sub-take-up spring 18 are connected in a so-called series manner via a ratchet wheel 16. (in series), and the main winding spring 14 is pre-wound and The secondary take-up springs 18 are wound tightly and housed.

0012 The roller 19 is made of a disc whose diameter is larger than that of the winding shaft 2. It is fitted into the protrusions 9, 9 of the collar mounting part 6 and is prevented from coming off. In addition, if the main winding The rotation torque of the spring 14 is three quarters, and the rotation torque of the sub winding spring 18 is three quarters. It is set as 1. Therefore, the sub winding spring 18 is smaller than the main winding spring 14. It is compact and has a small spring force (1/3).

[0013] Here, each outer end portion 14c of the main take-up spring 14 or the sub-take-up spring 18, The suspension system between the ratchet wheel 18c and the ratchet wheel 16 is, for example, A teardrop-shaped protrusion is provided on the inner bottom surface of the body chambers 15, 15a of the jet vehicle 16. is erected to the right with respect to the center line XX and facing slightly downward. sand That is, the protrusion 16b has a rounded tapered part 16c, a substantially semicircular rear large part 16d, and A cut is made at the arc portions 43, 43 connecting them, and at approximately the middle of the tapered portion 16c and the rear large portion 16d. an outer end 14c bent into a hook shape in the groove 16f; , 18c is inserted, the rear large part 16d is wound around the tapered part 16c, and then the tapered part 1 is wound again. 6c, and the inner end 18a is fixed to the notch 19a of the roller 19. . Then, the roller 19 is rotated appropriately, and the sub-winding spring 18 is tightened to tighten the so-called pre-winding spring. Make a roll.

[0014] The ratchet wheel 16 (casing) has a lid that covers the sub-winding spring 18. The body 20 is crowned. The ratchet wheel 16 has a ratchet tooth portion 17 which will be described later. The bar 27 is engaged and clockwise rotation is prevented in FIG. 2, and the lever 27 is It can rotate counterclockwise over the ratchet teeth 17. Additionally, the ratchet An arm 28 integrally formed with a lever 27 that can be engaged and detached from the toothed portion 17 projects from the substrate 1. It is rotatably supported on a provided shaft 1c, and its arm 28 consists of a solenoid 29. It is connected to a plunger 30 of the driving means via a spring pin 31. a One end of a spring 32 is locked to the arm 28, and the spring 32 is wound around the shaft 1c and attached to the substrate 1. The lever 27 is rotated and biased toward the plunger 30. ing. The solenoid 29 is fixed to the fixed part 1e of the board 1, and is driven by the wiring 33. Insert the belt tongue into the buckle through the button or close the door to turn it on. This is done electrically with a switch.

[0015] Note that, as shown in FIG. 1, the substrate 1 is provided with a cover 26 for covering it. The cover 26 and the board 1 are fixed to the main body 35 of the winding device with a plurality of fixing members 34. Ru. The main body 35 includes a frame 36 that rotatably supports the winding shaft 2, and a frame body 36 that is aligned with the winding shaft 2. A reel 37 that can be rotated on the body and a main body 35 vibrate or the winding shaft 2 is rotated in the drawing direction. The winding shaft 2 includes an emergency locking mechanism 38 that prevents the winding shaft 2 from rotating when the winding shaft 2 suddenly rotates. One end of a seat belt 39 is fixed to the reel 37 and wound clockwise.

[0016] The operation of the embodiment shown in FIG. 4 will be explained based on FIG. 5. The sub winding spring 18 is , before the unraveling operation, it is tightly wound, and its diameter is the minimum value a. in this case, The outer end 18d extending from the protrusion 16b to the sub-winding spring 18 is connected to the sub-winding spring 1. 8 and the tangent to the tapered portion 16c of the protrusion 16b are on a line A that is parallel to each other. , substantially match. Therefore, in order to wind up the webbing 39, the sub winding spring 18 is When the spring unwinds, the diameter of the sub-winding spring 18 increases and reaches its maximum value, as shown by the imaginary line. It becomes b. However, the outer end 18D of the sub-winding spring 18 is still A line where the tangent to the take-up spring 18 and the tangent to the tapered portion 16c of the protrusion 16b coincide with each other. It's on B. The angles P and R formed by these lines A and B and the tangent C of the arc portion 43 are respectively angle is less than 90 degrees. Therefore, even if the sub winding spring 18 expands or contracts, the outer end A deforming force concentrated only at one location does not act on the portion 18d. Therefore, the outer end 18 d does not undergo enough deformation to bend, so there is no breakage, and for this reason, The durability of the main take-up spring 14 or the sub-take-up spring 18 is improved.

[0017]

[Effect of the idea]

According to this invention explained above, when the spiral spring expands and contracts, its outer end The deformation angle of can be changed within a range smaller than 90 degrees, so the outer edge Since the amount of deformation concentrated in one place is small, there is no breakage or falling off, and the durability is extremely improved. do.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of this invention.

FIG. 2 is a general cross-sectional front view of the arrangement.

FIG. 3 is a general cross-sectional side view of the arrangement.

FIG. 4 is a plan view showing a suspension structure of a winding spring.

FIG. 5 is an explanatory diagram of the action.

FIG. 6 is a plan view of a conventional example.

FIG. 7 is an explanatory diagram of the operation of the conventional example.

[Explanation of symbols]

14, 18...Spiral spring, 14c, 18c, 18d...Outer end, 16...Case, 16b...Protrusion, 16c...Tapered part,
16d...rear part, 16f...groove

Claims (1)

[Scope of utility model registration request] Claim 1: A protrusion having an approximately teardrop-shaped planar shape is provided protrudingly on the inner bottom surface of a case housing the spiral spring, a groove is formed approximately in the center of the protrusion, and the outer end of the spiral spring is formed in the groove. The tangent of the spiral spring and the arc portion are wound tightly from the tapered portion to the inner end, from the tapered portion to the rear large portion, and then to the tapered portion again. A suspension device for a spiral spring, characterized in that the spiral springs are arranged so that tangent lines of and overlap in a straight line.