A pre-tightened two-stage force-limiting retractor and a seat belt device

Abstract

The present invention provides a pre-tightening type two-level force-limiting retractor and a seat belt device, the pre-tightening type two-level force-limiting retractor comprises: a force-limiting steel wire, a force-limiting rod, a fixed shaft, a pre-tightening wheel, a ratchet ring and a moving shaft; one end of the force-limiting rod is fixed on the fixed shaft, and the other end extends into a first accommodating groove in the moving shaft and is limited in the first accommodating groove; the end head of one end of the force-limiting steel wire is fixed on the fixed shaft, and the other end passes through the fixed shaft, the ratchet ring and the pre-tightening wheel in sequence, and then extends into the second accommodating groove in the moving shaft; when the moving shaft rotates, the force-limiting rod is driven to rotate synchronously, and the force-limiting steel wire is driven to be pulled out of the second accommodating groove and wound around the fixed shaft, and the groove on the fixed shaft provides an accommodating space for the wound force-limiting steel wire; the pre-tightening function can be realized, and the two-level force-limiting function is realized by the force-limiting rod and the force-limiting steel wire in combination; in case of emergency braking, frontal collision or rollover of the automobile, the pre-tightening function makes the occupant close to the seat, and the two-level force-limiting function reduces the degree of injury to the occupant's chest.

Description

Technical Field

[0001] The present invention relates to the technical field of safety belts, in particular to a pre-tensioned two-stage force-limiting retractor and a safety belt device. Background Art

[0002] The seat belt is made of extremely strong synthetic fiber and has a self-locking retractor. After the seat belt is fastened, the retractor will automatically tighten it. In the event of emergency braking, head-on collision or rollover, the occupants will cause the seat belt to be stretched quickly and violently. At this moment, the self-locking function of the retractor can instantly lock the seat belt, allowing the occupants to stick close to the seat to avoid falling out of the vehicle or being injured in a collision.

[0003] However, with most seat belt products currently on the market, in the event of emergency braking, head-on collision or rollover, the occupant's chest will be subject to greater tension from the seat belt, making it vulnerable to damage. Summary of the invention

[0004] The purpose of the present invention is to provide a pre-tensioned two-stage force-limiting retractor and a seat belt device, aiming to solve the problem in the prior art that in most seat belt device products currently on the market, when the vehicle encounters emergency braking, head-on collision or rollover, the occupant's chest is subjected to a large pulling force from the seat belt.

[0005] In order to solve the above technical problems, the present invention provides a pre-tightened two-stage force-limiting retractor, comprising:

[0006] Force-limiting steel wire, force-limiting rod, fixed shaft, preload wheel, ratchet ring, moving shaft;

[0007] One end of the force-limiting rod is fixed on the fixed shaft, and the other end extends into the first receiving groove in the moving shaft and is limited in the first receiving groove;

[0008] The end of one end of the force-limiting steel wire is fixed on the fixed shaft, and the other end passes through the fixed shaft, the ratchet ring, and the preload wheel in sequence, and then extends into the second receiving groove in the moving shaft;

[0009] When the movable shaft rotates, the force-limiting rod is driven to rotate synchronously, and the force-limiting steel wire is driven to be pulled out from the second accommodating groove and wound on the fixed shaft. The groove on the fixed shaft provides an accommodating space for the wound force-limiting steel wire.

[0010] Optionally, a first hole is drilled at the maximum material thickness of the ball concave edge of the preload wheel, the first hole is visible from the middle ball concave of the preload wheel, and the force-limiting steel wire passes through the first hole.

[0011] Optionally, a chamfered hole expansion structure is provided at the position where the first hole passes through the force-limiting steel wire.

[0012] Optionally, a chamfer structure is provided at the notch of the second accommodating groove.

[0013] Optionally, the length of the force-limiting steel wire is greater than or equal to half a circle and less than or equal to one circle when it is wrapped around the fixed axis after being pulled out from the second accommodating groove.

[0014] Optionally, the force-limiting rod rotates 2 times.

[0015] Optionally, the movable shaft includes the first accommodating groove and an annular flange located at one end of the first accommodating groove; the second accommodating groove includes a first through hole portion and a first groove portion, the first through hole portion is located in the annular flange, and the first groove portion is visible from the outside of the movable shaft; the force limiting steel wire passes through the first through hole portion and the first groove portion in sequence.

[0016] Optionally, the dynamic shaft includes the first accommodating groove and an annular flange located at one end of the first accommodating groove; the second accommodating groove includes a second through hole portion and a third through hole portion, and the second through hole portion is located in the annular flange; the outer side wall of the dynamic shaft has N expansions that are narrow at the bottom and wide at the top and are arranged side by side in the axial direction, and the side wall of the expansion is provided with a through hole as the third through hole portion; the force limiting steel wire passes through the second through hole portion and the third through hole portion in sequence.

[0017] Optionally, the diameter of the groove on the fixed shaft is larger than the diameter of the force-limiting steel wire.

[0018] In order to solve the above technical problems, the present invention further provides a seat belt device, comprising the pre-tensioned two-stage force-limiting retractor as described in any one of the above items.

[0019] Beneficial Effects

[0020] The present invention provides a pre-tightening type two-level force-limiting retractor and a seat belt device, the pre-tightening type two-level force-limiting retractor comprises: a force-limiting steel wire, a force-limiting rod, a fixed shaft, a pre-tightening wheel, a ratchet ring, and a moving shaft; one end of the force-limiting rod is fixed on the fixed shaft, and the other end extends into a first accommodating groove in the moving shaft and is limited in the first accommodating groove; the end head of one end of the force-limiting steel wire is fixed on the fixed shaft, and the other end passes through the fixed shaft, the ratchet ring, and the pre-tightening wheel in sequence, and then extends into the second accommodating groove in the moving shaft; when the moving shaft rotates, the force-limiting rod is driven to rotate synchronously, and the force-limiting steel wire is driven to be pulled out of the second accommodating groove and wound around the fixed shaft, and the groove on the fixed shaft provides an accommodating space for the wound force-limiting steel wire; through the above scheme, the pre-tightening function can be realized, and the two-level force-limiting function can be realized by using the force-limiting rod and the force-limiting steel wire in combination. In case of emergency braking, frontal collision or rollover of the vehicle, the pre-tightening function makes the occupant close to the seat, and the two-level force-limiting function reduces the degree of injury to the occupant's chest. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained like these drawings without paying creative work.

[0022] Figure 1 An exploded view schematic diagram of a pre-tightened two-stage force-limiting retractor provided in the first embodiment of the present invention;

[0023] Figure 2 A schematic diagram of a pre-tightened two-stage force-limiting retractor provided in Embodiment 1 of the present invention;

[0024] Figure 3 A schematic cross-sectional view of a pre-tightened two-stage force-limiting retractor provided in the first embodiment of the present invention;

[0025] Figure 4 A schematic diagram of a force-limiting steel wire in a straightened state provided in Embodiment 1 of the present invention;

[0026] Figure 5 A schematic diagram of a force-limiting steel wire in a winding state provided in Embodiment 1 of the present invention;

[0027] Figure 6 A schematic diagram of a preload wheel and a ratchet ring provided in Embodiment 1 of the present invention;

[0028] Figure 7 A schematic cross-sectional view of a first hole and a chamfered hole expansion structure provided in Embodiment 1 of the present invention;

[0029] Figure 8 A schematic diagram of a force-limiting steel wire passing through a first hole provided in Embodiment 1 of the present invention;

[0030] Fig. 9 A schematic diagram of a moving shaft provided in Embodiment 1 of the present invention;

[0031] Fig.10 A schematic diagram of a force-limiting steel wire passing through a moving shaft provided in Embodiment 1 of the present invention;

[0032] Fig.11 A schematic diagram of a curve showing a force limit value changing over time provided in the first embodiment of the present invention;

[0033] Fig.12 A schematic diagram of a seat belt device provided in Embodiment 2 of the present invention;

[0034] Force-limiting steel wire 10, force-limiting rod 11, fixed shaft 12, preload wheel 13, ratchet ring 14, moving shaft 15, first accommodating groove 21, second accommodating groove 22, groove 23, first hole 24, chamfered hole expansion structure 25, chamfered structure 26, coil spring assembly 30, bracket 31, lower positioning 32, bent pipe assembly 33, belt sensing assembly 34, vehicle sensing assembly 35, cover assembly 36, lock cover 37, preloaded secondary force-limiting retractor 38. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Embodiment 1

[0037] This embodiment will provide a pre-tightened two-stage force-limiting retractor, see Figures 1 to 11 The pre-tightened two-stage force-limiting retractor comprises:

[0038] Force-limiting steel wire 10, force-limiting rod 11, fixed shaft 12, preload wheel 13, ratchet ring 14, moving shaft 15;

[0039] One end of the force limiting rod 11 is fixed on the fixed shaft 12, and the other end extends into the first receiving groove 21 in the moving shaft 15 and is limited in the first receiving groove 21;

[0040] One end of the force-limiting wire 10 is fixed on the fixed shaft 12, and the other end passes through the fixed shaft 12, the ratchet ring 14, and the preload wheel 13 in sequence, and then extends into the second receiving groove 22 in the moving shaft 15;

[0041] The preload wheel 13 and the ratchet ring 14 cooperate to achieve the preload function;

[0042] When the moving shaft 15 rotates, it drives the force-limiting rod 11 to rotate synchronously, and drives the force-limiting steel wire 10 to be pulled out from the second accommodating groove 22 and wound around the fixed shaft 12. The groove 23 on the fixed shaft 12 provides an accommodating space for the wound force-limiting steel wire 10.

[0043] Through the above scheme, the pre-tightening function can be realized, and the secondary force limiting function can be realized by using the force limiting rod 11 and the force limiting wire 10. In the event of emergency braking, head-on collision or rollover of the car, the pre-tightening function makes the occupant close to the seat, and the secondary force limiting function reduces the degree of injury to the occupant's chest.

[0044] Optionally, the preload wheel 13 and the ratchet ring 14 are integrally formed.

[0045] Optionally, the length of the force-limiting steel wire 10 after being pulled out from the second accommodating groove 22 and wrapped around the fixed axis 12 is greater than or equal to half a circle and less than or equal to one circle.

[0046] Optionally, the force-limiting rod 11 rotates 2 times.

[0047] See also Fig.11 First, the force-limiting steel wire 10 is in a straightened state; in the early stage of force limitation, the force-limiting steel wire 10 and the force-limiting rod 11 work together to output a high force value; in the late stage of force limitation, only the force-limiting rod 11 works to output a low force value.

[0048] The front end of the force-limiting steel wire 10 is high in force-limiting, and the rear end does not participate because it is only rotated within one circle. The force-limiting rod 11 is the force-limiting rod in the entire stage, and the force-limiting rod 11 rotates 2 circles.

[0049] Early stage of force limitation: After the pawl locks the fixed shaft 12, one end of the force-limiting wire 10 and the force-limiting rod 11 is fixed with the fixed shaft 12 and the preload wheel 13, while the other end of the force-limiting rod 11 rotates with the moving shaft 15. At the same time, the force-limiting wire 10 is pulled out of the circular hole of the moving shaft 15 and wound on the fixed shaft 12. The groove 23 on the moving shaft 15 provides a storage space for the wound and bent force-limiting wire 10. At this time, due to the bending and winding of the force-limiting wire 10, the torsion of the force-limiting rod 11 together forms the front end of the secondary force-limiting curve with a higher force value.

[0050] Late stage of force limiting: When the adjustable force limiting wire 10 (generally no more than 1 turn) is completely pulled out from the driven shaft 15, the front end of the secondary force limiting curve ends. After that, the force limiting function is that the force limiting rod 11 continues to rotate, forming the rear low force value part of the secondary force limiting curve.

[0051] Only one steel wire is added to realize the secondary force limiting function, reduce the specifications of parts, and save management costs. The steel wire is easy to assemble and can be installed in the retractor at the end.

[0052] Optionally, a first hole 24 is drilled at the maximum material thickness of the ball concave edge of the preload wheel 13, and the first hole 24 can be seen from the middle ball concave of the preload wheel 13, and the force-limiting steel wire 10 passes through the first hole 24. That is, the force-limiting steel wire 10 passes through the maximum material thickness of the ball concave edge of the preload wheel 13.

[0053] Optionally, a chamfered hole expansion structure 25 is provided at the position where the first hole 24 passes through the force-limiting steel wire 10, so as to provide a space for the force-limiting steel wire 10 to bend and deform.

[0054] Optionally, a chamfer structure 26 is provided at the notch of the second receiving groove 22 to provide space for the bending and deformation of the force-limiting steel wire 10. The bending angle determines the bending force. The force-limiting steel wire 10 is bent along the chamfer, and the torsion of the force-limiting rod 11 is coordinated to achieve a high force value in the early stage of the secondary force-limiting.

[0055] Optionally, in one embodiment, the dynamic shaft 15 includes a first receiving groove 21 and an annular flange at one end of the first receiving groove 21; the second receiving groove 22 includes a first through hole portion and a first groove 23 portion, the first through hole portion is located in the annular flange, and the first groove 23 portion is visible from the outside of the dynamic shaft 15; the force-limiting steel wire 10 passes through the first through hole portion and the first groove 23 portion in sequence. To ensure the service life of the mold, the first groove 23 portion on the dynamic shaft 15 collides with the outside.

[0056] Optionally, in another embodiment, the dynamic shaft 15 includes a first receiving groove 21 and an annular flange at one end of the first receiving groove 21; the second receiving groove 22 includes a second through hole portion and a third through hole portion, the second through hole portion is located in the annular flange; the outer wall of the dynamic shaft 15 has N flared openings arranged side by side in the axial direction, which are narrow at the bottom and wide at the top, and the side wall of the flared opening is provided with a through hole as the third through hole portion; the force-limiting steel wire 10 passes through the second through hole portion and the third through hole portion in sequence. Optionally, N is 3 or 4, etc.

[0057] Optionally, the diameter of the groove 23 on the fixed shaft 12 is greater than the diameter of the force-limiting steel wire 10 .

[0058] Optionally, the end of the force-limiting steel wire 10 may be a round head, a flat head, etc.

[0059] The pre-tightening type two-stage force-limiting retractor 38 of this embodiment also has the functions of locking, accepting pre-tightening to drive the webbing to rewind, and the like.

[0060] Embodiment 2

[0061] See also Fig.12 This embodiment also provides a seat belt device, including any one of the above-mentioned pre-tensioned two-stage force-limiting retractors 38.

[0062] The safety belt device of this embodiment further includes a coil spring assembly 30, a bracket 31, a lower positioning assembly 32, a bent pipe assembly 33, a belt sensor assembly 34, a vehicle sensor assembly 35, a cover assembly 36, and a lock cover 37;

[0063] The coil spring assembly 30 is used to reel the webbing into the retractor;

[0064] The bracket 31 is used to support the entire retractor;

[0065] The lower positioning 32 is used to provide positioning for the bent pipe;

[0066] The bent pipe assembly 33 is used to push the marbles through the high-pressure gas generated by the gunpowder to achieve the pre-tightening function;

[0067] The belt sensing component 34 is used for the webbing pull-out acceleration locking trigger mechanism;

[0068] The vehicle sensing component 35 is used for the vehicle body inclination angle and acceleration locking trigger mechanism;

[0069] The cover assembly 36 is used to form a support body together with the bracket 31 to collect the pre-tightened marbles;

[0070] The locking cover 37 is used for supporting and positioning.

[0071] The above are only preferred embodiments of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the principles of the present invention. These improvements and supplements should also be regarded as the scope of protection of the present invention.

Claims

1. A pre-tightened two-stage force-limiting retractor, characterized in that: include: Force-limiting steel wire, force-limiting rod, fixed shaft, preload wheel, ratchet ring, moving shaft; One end of the force-limiting rod is fixed on the fixed shaft, and the other end extends into the first receiving groove in the moving shaft and is limited in the first receiving groove; The end of one end of the force-limiting steel wire is fixed on the fixed shaft, and the other end passes through the fixed shaft, the ratchet ring, and the preload wheel in sequence, and then extends into the second receiving groove in the moving shaft; When the movable shaft rotates, the force-limiting rod is driven to rotate synchronously, and the force-limiting steel wire is driven to be pulled out from the second receiving groove and wound on the fixed shaft, and the groove on the fixed shaft provides a receiving space for the wound force-limiting steel wire; The movable shaft comprises the first accommodating groove and an annular flange located at one end of the first accommodating groove; the second accommodating groove comprises a first through hole portion and a first groove portion, the first through hole portion is located in the annular flange, and the first groove portion is visible from the outside of the movable shaft; the force-limiting steel wire passes through the first through hole portion and the first groove portion in sequence; Or the movable shaft includes the first accommodating groove and an annular flange located at one end of the first accommodating groove; the second accommodating groove includes a second through hole portion and a third through hole portion, and the second through hole portion is located in the annular flange; the outer side wall of the movable shaft has N expansions that are narrow at the bottom and wide at the top and are arranged side by side in the axial direction, and the side wall of the expansion is provided with a through hole as the third through hole portion; the force-limiting steel wire passes through the second through hole portion and the third through hole portion in sequence.

2. The pre-tightened two-stage force-limiting retractor according to claim 1, characterized in that: A first hole is drilled at the maximum material thickness of the ball concave edge of the preload wheel, the first hole can be seen from the middle ball concave of the preload wheel, and the force-limiting steel wire passes through the first hole.

3. The pre-tightened two-stage force-limiting retractor according to claim 2, characterized in that: A chamfered hole expansion structure is provided at the position where the first hole passes through the force-limiting steel wire.

4. The pre-tightened two-stage force-limiting retractor according to claim 1, characterized in that: A chamfered structure is provided at the notch of the second accommodating groove.

5. The pre-tightened two-stage force-limiting retractor according to any one of claims 1 to 4, characterized in that: The length of the force-limiting steel wire is greater than or equal to half a circle and less than or equal to one circle when it is wound around the fixed axis after being pulled out from the second receiving groove.

6. The pre-tightened two-stage force-limiting retractor according to any one of claims 1 to 4, characterized in that: The force limiting rod rotates 2 times.

7. The pre-tightened two-stage force-limiting retractor according to any one of claims 1 to 4, characterized in that: The diameter of the groove on the fixed shaft is greater than the diameter of the force-limiting steel wire.

8. A seat belt device, characterized in that: It comprises a pre-tightened two-stage force-limiting retractor as described in any one of claims 1 to 7.

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