Frame rear fork of two-wheeled vehicle

Abstract

The frame rear fork comprises a rear fork body and a seat tube, the rear fork body comprises an upper fork arm and a lower fork arm which form an included angle, and the tail end of the upper fork arm and the tail end of the lower fork arm are jointly fixed to the tail end of the rear fork body. The frame comprises a rear fork connecting part a and a rear fork connecting part b, and the rear fork connecting part b is arranged on the front side of the seat tube; a cross arm is fixed on the lower fork arm; when the front end of the upper fork arm and the front end of the lower fork arm are detachably connected to the rear fork connecting part a and the rear fork connecting part b respectively, the cross arm makes contact with the rear side of the seat tube. The detachable characteristic of the rear fork is met, and meanwhile the effect of restraining the connecting portion of the rear fork on a bumpy road from loosening is achieved.

Description

Technical Field

[0001] The utility model belongs to the field of two-wheel vehicle frames. Background Art

[0002] Generally, the front end of the rear fork of a two-wheel vehicle is welded to the vehicle frame. The welding method is not only not conducive to the miniaturization and modularization of the vehicle frame during factory production, thus being unfavorable for transportation; at the same time, in the welded integral structure on bumpy roads, very strong impact stress will be formed at the welding part of the front end of the rear fork, and there will be a problem of crack damage at the welding place.

[0003] If the front end of the rear fork is detachably locked to the vehicle frame by means of screw locking, although it is conducive to transportation in the disassembled state, on bumpy roads, the screw locking part between the front end of the rear fork and the vehicle frame will undergo slight torsion due to the elastic deformation of the rear fork during bumping. Although there will be no crack phenomenon like the welding process, the screw locking part is prone to loosen to a certain extent. Summary of the Invention

[0004] Object of the Invention: In order to overcome the deficiencies existing in the prior art, the utility model provides a rear fork of a two-wheel vehicle frame, which not only satisfies the detachable characteristic of the rear flat fork, but also plays a role in suppressing the looseness of the connection part of the rear flat fork on bumpy roads.

[0005] Technical Solution: To achieve the above object, a rear fork of a two-wheel vehicle frame of the utility model includes a rear fork and a seat tube. The rear fork includes an upper fork arm and a lower fork arm forming an angle. The tail ends of the upper fork arm and the lower fork arm are commonly fixed to the rear end of the rear fork; the vehicle frame includes a rear fork connection part a and a rear fork connection part b, and the rear fork connection part b is on the front side of the seat tube; a cross arm is fixed on the lower fork arm; when the front ends of the upper fork arm and the lower fork arm are respectively detachably connected to the rear fork connection part a and the rear fork connection part b, the cross arm contacts the rear side of the seat tube.

[0006] Further, a plurality of structural arms are connected between the upper fork arm and the lower fork arm.

[0007] Further, the rear fork connection part a is horizontally fixed on the seat tube, and there is a locking hole a on the rear fork connection part a. There is a bayonet at the rear side of the rear fork connection part a. The front end of the upper fork arm is provided with an upper fork lock hole. When the front end of the upper fork arm is inserted into the bayonet, the upper fork lock hole is aligned with the locking hole a, and is locked by a screw locking member.

[0008] Further, the rear fork connection part b is provided with a locking hole b, and the front end of the lower fork arm is provided with a lower fork lock hole; when the lower fork lock hole is aligned with the locking hole b and locked by a screw locking member, the cross arm is vertically and limitably in contact with the rear side surface of the seat tube.

[0009] Furthermore, the lower end of the seat tube is fixedly connected to the bottom bracket shell. The front side of the bottom bracket shell is fixedly connected to the lower frame tube. A support arm is fixed on the lower frame tube, and a rear fork connection part b is fixed on the support arm a.

[0010] Furthermore, both ends of the rear fork connection part a are fixedly supported and connected to the lower frame tube by a pair of support arms b.

[0011] Furthermore, the seat tube is inclined backward.

[0012] Beneficial effects: When the two-wheel bicycle is traveling on a bumpy road section, when the rear wheel receives an upward impact force from the ground, the tail end of the rear fork will instantaneously receive an upward impact force. An upward bending elastic deformation will be instantaneously generated at the rear sections of both the upper fork arm and the lower fork arm, thereby causing a slight elastic upward swing movement of the rear fork tail end relative to the frame. Furthermore, it causes the cross arm fixed to the front part of the lower fork arm to also have a tendency to move upward. Since the cross arm cannot swing upward under the restriction of the rearward-inclined seat tube, the cross arm plays a role in suppressing the tendency of the front section of the lower fork arm to swing upward due to elastic deformation, thereby suppressing the relative twisting between the lower fork lock hole and the locking hole b, and further avoiding the problem of loosening of the detachable structure on bumpy road sections. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic structural view of the first perspective of this solution;

[0014] Figure 2 is a schematic structural view of the second perspective of this solution. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention will be further described below with reference to the accompanying drawings.

[0016] As shown in the attached Figure 1 and 2 figures, a rear fork of a two-wheel vehicle frame includes a rear fork 80 and a seat tube 7. From a lateral perspective, the rear fork 80 includes an upper fork arm 12 and a lower fork arm 9 that form an angle. The tail ends of the upper fork arm 12 and the lower fork arm 9 are jointly fixed to the rear fork tail end 10. In order to improve the anti-deformation ability of the rear fork, a plurality of structural arms 8 are welded or integrally connected between the upper fork arm 12 and the lower fork arm 9.

[0017] The frame includes a rear fork connecting portion 15 and a b rear fork connecting portion 4; the a rear fork connecting portion 15 is a transverse columnar structure, the middle of the a rear fork connecting portion 15 is transversely welded and fixed to the seat tube 7, there are a locking holes 16 at both ends of the a rear fork connecting portion 15, and there is a bayonet 82 at the rear side of the a rear fork connecting portion 15. An upper fork lock hole 14 is provided at the front end of the upper fork arm 12. When the front end of the upper fork arm 12 is inserted into the bayonet 82, the upper fork lock hole 14 is aligned with the a locking hole 16 and locked by a threaded locking member; the front sides of both ends of the a rear fork connecting portion 15 are fixedly supported and connected to the lower tube 3 of the frame through a pair of b support arms 2, so as to enhance the front-back force balance of the a rear fork connecting portion 15 and avoid the problem of excessive stress at the connection between the a rear fork connecting portion 15 and the seat tube 7.

[0018] The b rear fork connecting portion 4 is on the front side of the seat tube 7; the lower end of the seat tube 7 is fixedly connected to the bottom bracket seat 6, the front side of the bottom bracket seat 6 is fixedly connected to the lower tube 3 of the frame, and an a support arm 1 is fixed on the lower tube 3 of the frame. The b rear fork connecting portion 4 is transversely welded and fixed to the a support arm 1; a cross arm 84 is fixed on the lower fork arm 9; a b locking hole is provided on the b rear fork connecting portion 4, and a lower fork lock hole 5 is provided at the front end of the lower fork arm 9; when the front ends of the upper fork arm 12 and the lower fork arm 9 are respectively detachably connected to the a rear fork connecting portion 15 and the b rear fork connecting portion 4, the lower fork lock hole 5 is aligned with the b locking hole and locked by a threaded locking member. At this time, the cross arm 84 is vertically and limit-contact with the rear side of the seat tube 7.

[0019] Working principle: The seat tube 7 of this case is tilted backward. Although the upper fork arm 12, the lower fork arm 9 and the seat tube 7 form a stable triangular structure; when the two-wheeled bicycle is traveling on a bumpy road section, when the rear wheel receives an upward impact force from the ground, the tail end of the rear fork 80 will instantly receive an upward impact force, and the rear sections of the upper fork arm 12 and the lower fork arm 9 will instantly generate an upward bending elastic deformation, thereby causing the rear fork tail end 10 to have a slight elastic upward swing movement relative to the frame; furthermore, it causes the cross arm 84 fixed to the front part of the lower fork arm 9 to also have a tendency to move upward. Since the cross arm 84 cannot swing upward under the restriction of the backward-tilted seat tube 7, the cross arm 84 plays a role in suppressing the tendency of the front section of the lower fork arm 9 to swing upward due to elastic deformation, thereby suppressing the relative torsion between the lower fork lock hole 5 and the b locking hole, and further avoiding the problem of loosening of the detachable structure on the bumpy road section.

[0020] The above is only the preferred embodiment of the present invention. It should be pointed out that: for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A rear fork of a two-wheeled vehicle frame, characterized in that: The invention comprises a rear fork (80) and a seat tube (7), wherein the rear fork (80) comprises an upper fork arm (12) and a lower fork arm (9) which are angled with each other, and the tail ends of the upper fork arm (12) and the lower fork arm (9) are fixed to the rear fork tail end (10); the frame comprises a rear fork connecting portion a (15) and a rear fork connecting portion b (4), and the rear fork connecting portion b (4) is located at the front side of the seat tube (7); a cross arm (84) is fixed to the lower fork arm (9); when the front ends of the upper fork arm (12) and the lower fork arm (9) are detachably connected to the rear fork connecting portion a (15) and the rear fork connecting portion b (4), the cross arm (84) contacts the rear side of the seat tube (7).

2. The rear fork of a two-wheeled vehicle frame according to claim 1, characterized in that: A plurality of structural arms (8) are connected between the upper fork arm (12) and the lower fork arm (9).

3. The rear fork of a two-wheeled vehicle frame according to claim 1, characterized in that: A rear fork connecting portion (15) is transversely fixed to the seat tube (7), and a locking hole (16) is provided on the rear fork connecting portion (15). A bayonet (82) is provided on the rear side of the rear fork connecting portion (15), and an upper fork locking hole (14) is provided at the front end of the upper fork arm (12). When the front end of the upper fork arm (12) is inserted into the bayonet (82), the upper fork locking hole (14) is aligned with the locking hole (16) and is locked by a threaded locking member.

4. The rear fork of a two-wheeled vehicle frame according to claim 3, characterized in that: The rear fork connecting portion (4) is provided with a locking hole (b), and the front end of the lower fork arm (9) is provided with a lower fork locking hole (5); the lower fork locking hole (5) is aligned with the locking hole (b), and when locked by a threaded locking member, the cross arm (84) is vertically limited and contacts the rear side surface of the seat tube (7).

5. The rear fork of a two-wheeled vehicle frame according to claim 4, characterized in that: The lower end of the seat tube (7) is fixedly connected to the five-way seat (6), the front side of the five-way seat (6) is fixedly connected to the frame down tube (3), the frame down tube (3) is fixed with an a support arm (1), and the b rear fork connecting part (4) is fixed on the a support arm (1).

6. The rear fork of a two-wheeled vehicle frame according to claim 4, characterized in that: The two ends of the a rear fork connection part (15) are fixedly supported and connected to the frame lower tube (3) via a pair of b support arms (2).

7. The rear fork of a two-wheeled vehicle frame according to claim 1, characterized in that: The seat tube (7) is tilted rearward.

Images