Motorcycle frame structure

Abstract

The invention discloses a motorcycle frame structure, comprising a rear reducer mounting cross tube and left and right seat cushion guide beam tubes welded and fixed on the outer wall surface thereof, a weld A is formed between the two, a left and right frame lower tubes are welded to the support below the rear reducer mounting cross tube, a front vertical tube of the front of the vehicle extends left and right fuel tank guide beam tubes to the rear of the frame, the tail ends of the fuel tank guide beam tubes are welded and fixed to the outer wall surface of the rear reducer mounting cross tube, a weld B is formed between the two; the projections of the weld B and the weld A in the front and rear directions of the vehicle overlap; the inner walls of the left and right ends of the rear reducer mounting cross tube are welded with left and right reinforcing plates, a weld C is formed between the two; the projections of the weld C and the weld A in the front and rear directions of the vehicle overlap, or the distance between the two projections is less than 10 mm; through the above improvements, the longitudinal rigidity and transverse rigidity of the rear part of the frame and the connection strength are improved, so that the stress distribution under the force condition is effectively improved, and the high-speed stability of the vehicle when traveling with luggage is achieved.

Description

Technical Field

[0001] The invention relates to a motorcycle frame structure. Background Art

[0002] The motorcycle frame is the supporting skeleton of the motorcycle. It not only serves as a carrier for installing many body parts in the whole vehicle, but also supports the weight of the motorcycle passengers and luggage.

[0003] Common men's bicycle frame structures in the prior art are as follows: Figure 1 As shown, there are left and right seat cushion guide beam tubes 2' under the seat cushion, which are welded and fixed to the outer wall surface of the rear reducer mounting cross tube 1'. When the load on the rear part of the frame is heavy, that is, the weight of the passengers and luggage is heavy, the welding point between the seat cushion guide beam tube 2' and the rear reducer mounting cross tube 1' will produce large tensile stress. If the vehicle runs under this working condition for a long time, there is a risk of cracking of the frame.

[0004] Therefore, it is necessary to improve the above structure and provide a motorcycle frame structure with a more stable structure, so as to achieve high-speed stability when the vehicle is traveling with luggage. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a motorcycle frame structure.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] A motorcycle frame structure comprises a rear reducer mounting cross tube and left and right seat cushion guide beam tubes welded and fixed on the outer wall surface thereof, a weld A being formed at the weld connection between the two, a left and right frame lower tubes being welded and supported below the rear reducer mounting cross tube, a front vertical tube of the front of the vehicle extending left and right fuel tank guide beam tubes to the rear of the frame, the rear ends of the fuel tank guide beam tubes being welded and fixed on the outer wall surface of the rear reducer mounting cross tube, a weld B being formed at the weld connection between the two; the projections of the weld B and the weld A in the front-rear direction of the vehicle overlap; the inner walls of the left and right ends of the rear reducer mounting cross tube are welded with left and right reinforcing plates, a weld C being formed at the weld connection between the two; the projections of the weld C and the weld A in the front-rear direction of the vehicle overlap, or the distance between the two projections is less than 10 mm.

[0008] The weld of the fuel tank guide beam tube on the outer wall surface of the rear reducer installation transverse tube extends to the frame lower tube, and is combined with the weld of the frame lower tube on the outer wall surface of the rear reducer installation transverse tube to form a circle of annular welds.

[0009] The beneficial effects of the present invention are as follows: after the above improvements, the frame structure of the present invention forms effective mutual support through the left and right seat cushion guide beam tubes, the rear reducer mounting cross tube, the cross tube reinforcement plate, the left and right fuel tank guide beam tubes, and the left and right down tubes, thereby improving the longitudinal stiffness and lateral stiffness as well as the connection strength of the rear part of the frame, and achieving the high-speed stability of the vehicle when traveling with luggage. The force of the left and right seat cushion guide beam tubes can be transmitted to the left and right fuel tank guide beam tubes and the left and right down tubes through the cross tube reinforcement plate, thereby effectively improving the stress distribution at the welds between the left and right seat cushion guide beam tubes and the rear reducer mounting cross tube under stress conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0011] Figure 1 It is a structural schematic diagram of the prior art;

[0012] Figure 2 It is a schematic diagram of the structure of the present invention;

[0013] Figure 3 yes Figure 2 Schematic diagram of the local structure at N locations;

[0014] Figure 4 It is a schematic projection diagram of the present invention in the front and rear directions of the vehicle. DETAILED DESCRIPTION

[0015] Reference Figures 2 to 4 The motorcycle frame structure of the present invention comprises a rear shock absorber mounting transverse tube 1 for mounting a rear shock absorber, left and right seat cushion guide beam tubes 2 located below the seat cushion are welded and fixed to the outer wall surface of the rear shock absorber mounting transverse tube 1, and a weld A21 is formed at the welding connection between the two. Left and right frame down tubes 3 are also supported and welded below the rear shock absorber mounting transverse tube 1, and a front vertical tube 4 for mounting the front components extends left and right fuel tank guide beam tubes 5 to the rear of the frame, and the rear ends of the fuel tank guide beam tubes 5 are welded and fixed to the outer wall surface of the rear shock absorber mounting transverse tube 1, and a weld B51 is formed at the welding connection between the two; the projections of the weld B51 and the weld A21 in the front-rear direction of the vehicle overlap; the inner walls of the left and right ends of the rear shock absorber mounting transverse tube 1 are welded with left and right reinforcing plates 6, and a weld C61 is formed at the welding connection between the two; the projections of the weld C61 and the weld A21 in the front-rear direction of the vehicle overlap, or the distance between the two projections is less than 10 mm.

[0016] The left and right fuel tank guide beam tubes 5 are overlapped on the outer wall surface of the rear reducer mounting cross tube 1, and reinforcement plates 6 are arranged on the inner walls of the left and right ends of the rear reducer mounting cross tube 1. The projections of the welds in the front and rear directions of the vehicle overlap or the spacing is less than a certain value, so that when the vehicle is traveling with luggage, the applied force is not only borne by the left and right seat cushion guide beam tubes 2 and the rear reducer mounting cross tube 1, but also connected to the left and right fuel tank guide beam tubes 5 and the left and right lower tubes 3 through the cross tube reinforcement plate 6, thereby forming an effective support between them, improving the longitudinal stiffness and lateral stiffness and connection strength of the rear part of the frame, and realizing the high-speed stability of the vehicle when traveling with luggage. The force of the left and right seat cushion guide beam tubes can be transmitted to the left and right fuel tank guide beam tubes and the left and right lower tubes through the cross tube reinforcement plate, thereby effectively improving the stress distribution at the welds between the left and right seat cushion guide beam tubes and the rear reducer mounting cross tube under the force condition.

[0017] The cross tube reinforcement plate 6 plays a vital role in improving the stress distribution of the above-mentioned pipe fittings. Stress calculation and experimental verification show that when the projections of the weld C61 of the cross tube reinforcement plate 6 on the inner wall of the rear reducer mounting cross tube 1 and the weld A21 of the left and right seat cushion guide tubes 2 on the outer wall of the rear reducer mounting cross tube 1 overlap or the distance is less than 10 mm, the stress distribution of the rear part of the frame under stress is greatly improved, which can effectively avoid the problem of frame cracking caused by stress concentration.

[0018] Preferably, the weld B51 of the tank guide beam tube 5 on the outer wall surface of the rear reducer mounting cross tube 1 extends to the frame down tube 3, and is combined with the weld B51 of the frame down tube 3 on the outer wall surface of the rear reducer mounting cross tube 1 to form a circular weld, which not only simplifies the welding process, but also helps to improve the force performance and stress distribution of the rear part of the frame.

Claims

1. A motorcycle frame structure, comprising a rear reduction mounting cross tube (1) and left and right seat cushion guide beam tubes (2) welded and fixed to the outer wall surface thereof, the welded connection between the two forming a weld seam A (21), and left and right frame lower tubes (3) are also supported and welded below the rear reduction mounting cross tube (1), characterized in that: The front vertical tube (4) of the vehicle head extends to the rear of the vehicle frame to form left and right fuel tank guide beam tubes (5), and the rear ends of the fuel tank guide beam tubes (5) are welded and fixed to the outer wall surface of the rear reducer mounting cross tube (1), and the welding connection between the two forms a weld seam B (51); the projections of the weld seam B (51) and the weld seam A (21) in the front and rear directions of the vehicle overlap; the inner walls of the left and right ends of the rear reducer mounting cross tube (1) are welded with left and right reinforcing plates (6), and the welding connection between the two forms a weld seam C (61); the projections of the weld seam C (61) and the weld seam A (21) in the front and rear directions of the vehicle overlap, or the distance between the two projections is less than 10 mm.

2. The motorcycle frame structure according to claim 1, characterized in that: The weld B (51) of the oil tank guide beam tube (5) on the outer wall surface of the rear reducer mounting transverse tube (1) extends to the frame lower tube (3) and is combined with the weld of the frame lower tube (3) on the outer wall surface of the rear reducer mounting transverse tube (1) to form a circular weld.

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