JPH0742881Y2 - Spiral spring suspension - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a suspension device for a spiral spring, and more particularly, when the outer end of the spiral spring is fixed to a storage case, the spring is cut off or fixed. The present invention relates to a suspension device for preventing separation from a section.

[Prior Art] In general, there are many devices using a spiral spring, but especially in a vehicle safety belt device, a webbing (seat belt) is used.
In order to wind the reel, the retractor is provided with a spiral spring that constantly biases the winding shaft that rotates the reel.

By the way, a spiral spring is made by winding a strip-shaped thin metal piece in a spiral shape.The inner end of the spiral spring is a biased side shaft such as a winding shaft, and the outer end of the spiral spring is a fixed side such as a storage case. Fasten each. In order to fix the outer end portion, as shown in FIG. 6, a barbed-shaped projection 51 is provided on the inner bottom surface of the storage case 50 that also serves as a ratchet wheel, and a recess formed at the rear of the projection 51 is formed. The end 53 is engaged with 52, and the outer end of the spiral spring 54 is
56 was wound twice.

[Problems to be Solved by the Invention] However, according to the above-described conventional spiral spring suspension device, when the spiral spring 54 expands and contracts, the outer end portion 56 is separated from the seventh end.
As shown by the phantom line in the figure, it swings significantly from a state substantially orthogonal to the protrusion 51 to a state where it substantially overlaps the tangent line of the arc portion 57 of the protrusion 51, and the contact point with the protrusion 51 is large. Since C does not change substantially and is a constant portion, a bending force is applied to the portion C, so that the outer end portion 56 is likely to be cut and durability may be reduced.

Therefore, the present invention has been made for the purpose of eliminating the above inconvenience.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a protrusion having a substantially crescent-shaped cross section on a bottom surface of a case for accommodating a spiral spring, and the chord portion of the protrusion is provided. An engaging hole into which the outer end portion of the spiral spring is inserted is provided, and the outer end portion is fixed to the engaging hole to wind the spiral spring from the chord portion to the arc portion. A spiral spring suspension device is arranged so that the tangent line of the arc portion is linearly overlapped.

[Operation] According to the present invention having the above-mentioned configuration, even if the spiral spring expands and contracts and its diameter shrinks or expands, the outer end portion of the spiral spring is always constant with the projection portion to which it is fixed. Since they are in contact with each other at an angle, the amount of deformation of the outer end is constant, and no bending force is applied to the outer end.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. First
As shown in FIG. 3 to FIG. 3, the shaft hole 1a formed in the substrate 1
The take-up shaft 2 of the seatbelt take-up device main body 35 is projected from the above, and the first gear 3 is fitted on the take-up shaft 2. The shaft 4a of the second gear 4 that meshes with the gear 3 is rotatably supported in the shaft hole 1f formed in the substrate 1 (see FIG. 3).
Is integrally formed with a shaft portion 5, and a roller mounting portion 6 having an oval cross section is formed at an end portion of the shaft portion 5. A shaft hole 7 is formed in the center of the roller mounting portion 6 in the axial direction, and the roller mounting portion 6 is axially divided into grooves 8 and 8 which face each other in the diametrical direction.
And the projections 9 are formed on the outer peripheral surface of the arc portion. Third gears 3a, 3a that mesh with the second gear 4 and are the same gears as the first gear 3
Are rotatably supported by shafts 1b, 1b projecting from the substrate 1 at the remaining apexes of an equilateral triangle with the winding shaft 2 as the apex. Then, the internal gear 10 (see FIGS. 2 and 3) having the inner peripheral tooth portion 10a meshing with the gears 3, 3a, 3a is loosely fitted to the shaft portion 5. The inner tooth portion 10a and the gear 4,
The ratio of the number of teeth of 3,3a is set to 3: 1. The internal gear 10 is a tubular body having a substantially convex cross section, and includes a shaft portion 11 having a diameter larger than that of the winding shaft 2, and a shaft hole 12 into which the shaft portion 5 is loosely fitted is bored in the shaft portion 11. Has been done. The shaft portion 11 has notches 13 and 13 for locking the inner end portion 14a of the main winding spring 14 formed of a spiral spring. A ratchet wheel 16 having an H-shaped cross section, which forms a barrel chamber 1515a (see FIG. 3) for accommodating the main winding spring 14 and a sub-winding spring 18 described later, is loosely fitted to the shaft portion 5, and the ratchet wheel 16 Has a ratchet tooth portion 17 on its outer peripheral surface, and a sub-winding spring 18 composed of a spiral spring is housed in the other body chamber 15a of the ratchet wheel 16. The outer end portions 14b, 18b of the main winding spring 14 and the sub-winding spring 18 are respectively in the body chamber 15,
The protrusions 16b, 16e for spring engagement formed on the inner peripheral edge of 15a are locked. Further, the inner end portion 18a of the sub winding spring 18 is locked to either one of the locking grooves 19a, 19a of the roller 19 fitted to the roller mounting portion 6 of the shaft portion 5 and The sub winding spring 18 is connected to the shaft portion 5 in a so-called series (series) via the ratchet wheel 16, the main winding spring 14 is pre-wound, and the sub winding spring 18 is wound tight. Each is stored. The roller 19 is composed of a disk body having a diameter larger than that of the winding shaft 2, and is fitted to the protrusions 9 of the roller mounting portion 6 to prevent the roller from coming off. The main winding spring 14 has a rotational torque of 3/4, and the auxiliary winding spring 18 has a rotational torque of ¼. Therefore, the sub-winding spring 18 is smaller and more compact than the main winding spring 14, and its spring force is smaller (one third).

Here, the suspension device between the outer end portions 14c, 18c of the main winding spring 14 or the sub-winding spring 18 and the ratchet wheel 16 is, for example, as shown in FIG. 1
On the inner bottom surface of 5,15a, protrusions 16b, 16e of a substantially crescent-shaped cross section,
It is erected at an angle slightly inclined with respect to the center line XX. For example, the protruding portion 16b has an engaging hole 42 formed substantially in the center of the chord portion 41, and the arc portion 43 thereof has a ratchet tooth portion 17b.
Facing each other and having an arcuate shape with a constant interval. The end 18b of the sub-winding spring 18 is inserted into the engaging hole 42 of the projection 16b from above, and the outer end 18c winds and fixes the projection 16b so as to surround the projection 16b at least double. And
Insert the inner end 18a of the sub-winding spring 18 into the cut portion 1 of the roller 19.
The roller 19 is fixed to the shaft 9a, the roller 19 is appropriately rotated, and the sub-winding spring 18 is tightened to perform so-called pre-winding.

Then, the ratchet wheel 16 (casing) is covered with a lid 20 that covers the auxiliary winding spring 18. Ratchet car 16
Is engaged with the ratchet tooth portion 17 by a lever 27 described later,
As shown in FIG. 2, the clockwise rotation is prevented, and the lever 27 can pass over the ratchet teeth 17 and rotate counterclockwise. Further, an arm 28 integrally formed with a lever 27 that can be engaged with and disengaged from the ratchet teeth 17 is rotatably supported by a shaft 1c protruding from the substrate 1, and the arm 28 is a solenoid.
A spring pin is attached to the plunger 30 of the drive means consisting of 29.
It is connected through 31. One end of a spring 32 is locked to the arm 28, the spring 32 is wound around a shaft 1c and locked to a spring hook 1d of the substrate 1, and the lever 27 is rotationally biased toward the plunger 30. The solenoid 29 is fixed to the fixed portion 1e of the substrate 1, and is driven electrically by a switch that is turned on when the tongue of the belt is inserted into the buckle via the wiring 33 or the door is closed.

The substrate 1 is provided with a cover 26 that covers the substrate 1, and the cover 26 and the substrate 1 are fixed to the main body 35 of the winding device by a plurality of fixing members 34. The main body 35 includes a frame 36 that rotatably supports the winding shaft 2, a reel 37 that can rotate integrally with the winding shaft 2, a vibration of the main body 35, or a rapid rotation of the winding shaft 2 in the pull-out direction. Then, the emergency lock mechanism 38 is provided to prevent the winding shaft 2 from rotating. One end of the seat belt 39 is fastened to the reel 37 and is wound clockwise.

In the above structure, the sub-winding spring 18 is wound and tightened as shown in FIG. 5 before the unwinding operation, and its diameter is the minimum value a. In this case, the outer end portion 18c extending from the protruding portion 16b to the sub winding spring 18 is on a line in which the tangent line A of the sub winding spring 18 and the tangent line B of the arc portion 43 of the protruding portion 16b are parallel to each other, and Match each other. So webbing
When the sub-winding spring 18 is unwound to wind 39, the diameter of the sub-winding spring 18 expands to the maximum value b, as shown by the phantom line. However, the outer end portion 18c of the auxiliary winding spring 18 is
Is still the tangent line A'of the sub-winding spring 18 and the protrusion 16b.
There the on lines tangent B 'and coincide with each other in the arc portion 43, moreover, the contact C of the protruding portion 16b moves to C _1. That is, even if the sub-winding spring 18 expands and contracts, the outer end portion 18c is not subjected to a deforming force that concentrates at only one place. Therefore, since the outer end portion 18c does not have a deformation amount enough to be bent, the outer end portion 18c is not broken, and thus the durability of the main winding spring 14 or the sub winding spring 18 is improved.

[Effects of the Invention] According to the invention described above, a substantially crescent-shaped protrusion is provided on the inner bottom surface of the case that houses the spiral spring, and the outer end of the spiral spring is inserted into the chord of the protrusion. With a dowel,
An outer end portion is fixed to the engaging hole, and a spiral spring is wound from the chord portion to the arc portion, and the tangent line of the spirally wound spiral spring and the tangent line of the arc portion are arranged in a straight line. Therefore, when the spiral spring expands and contracts, the contact point between the outer end and the protrusion changes so that the amount of deformation concentrated at one location on the outer end is small, so there is no breakage and durability. Greatly improved.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention, FIG. 2 is a general sectional front view of the arrangement, FIG. 3 is a general sectional side view of the arrangement, and FIG. 4 is a suspension of a winding spring. FIG. 5 is a plan view showing the structure, FIG. 5 is an operation explanatory view thereof, FIG. 6 is a plan view of a conventional example, and FIG. 7 is an operation explanatory view thereof. A, B, A ′, B ′ …… tangent, C, C ₁ …… contact, 14,18 …… spiral spring, 14c, 18c …… outer end, 16 …… case, 16b …… protrusion, 41 ...... Engagement hole, 42 ...... string part, 43 ...... arc part

Claims (1)

[Scope of utility model registration request] 1. A projecting portion having a substantially crescent-shaped cross section is projected from an inner bottom surface of a case for accommodating the spiral spring, and an engaging hole into which an outer end portion of the spiral spring is inserted is provided in a chord portion of the projecting portion. An outer end portion is fixed to the engagement hole, and a spiral spring is wound from the chord portion to the arc portion, and the tangential line of the wound spiral spring and the tangent line of the arc portion are arranged in a straight line. A suspension device for a spiral spring, characterized in that