CN110816734B - Scooter, frame and front support assembly pipe fittings - Google Patents

Abstract

The present invention relates to a scooter, a frame and a front support composite pipe. The front support composite pipe comprises a main pipe, two side pipes and a front transverse pipe. The end face of the front transverse pipe coincides with the side wall of the side pipe, and the end face of the front transverse pipe is welded to the side wall of the side pipe to form an annular weld. The lower weld portion of the annular weld is spaced apart from the lower edge portion of the side pipe, and the distance between the lower weld portion of the annular weld and the upper weld portion of the annular weld is smaller than the distance between the front weld portion of the annular weld and the rear weld portion of the annular weld. The above-mentioned front support composite pipe, on the one hand, can make the end face of the front transverse pipe and the side wall of the side pipe firmly bonded, and on the other hand, can make the annular weld as far away from the lower edge portion of the side pipe as possible, so that the lower edge portion of the side pipe is less affected by the heat of the annular weld, thereby avoiding the undesirable phenomenon that the lower edge portion of the side pipe is prone to brittle cracking under the action of external force.

Description

Scooter, frame and front support assembly pipe fittings

Technical Field

The invention relates to the technical field of vehicles, in particular to a scooter, a frame and a front support combined pipe member.

Background Art

A scooter is a popular means of transportation. The scooter includes a frame, and the frame includes a front support assembly pipe member located at the front of the vehicle body. The front support assembly pipe member includes a main pipe and two side pipes arranged on both sides of the main pipe. Generally, for the front support assembly pipe member in which the main pipe is not connected to the middle cross pipe of the frame, it also includes a front cross pipe connected to the two side pipes, and the overall structural stability of the front support assembly pipe member is enhanced by the front cross pipe. However, during use, please refer to Figure 10, the weld area C between the end of the side pipe and the front cross pipe overlaps or approaches the stress concentration area A, and the lower edge portion of the side wall corresponding to the end of the side pipe and the front cross pipe (the lower edge portion refers to the portion of the side wall of the side pipe closest to the ground in the circumferential surface direction of the side wall of the side pipe when the scooter is normally placed on the horizontal ground; correspondingly, the upper edge portion refers to the portion of the side wall of the side pipe farthest from the ground in the circumferential surface direction of the side wall of the side pipe) is prone to cracking.

Summary of the invention

Based on this, it is necessary to overcome the defects of the prior art and provide a scooter, a frame and a front support combined pipe fitting, which can avoid the undesirable phenomenon of cracking of the side pipe during use.

The technical scheme is as follows: a front support combined pipe fitting, comprising: a main pipe, two side pipes, both of which are connected to the main pipe; a front cross pipe, the two ends of which are respectively connected to the two side pipes, the end face of the front cross pipe coincides with the side wall of the side pipe, the end face of the front cross pipe is welded to the side wall of the side pipe to form an annular weld, the lower weld portion of the annular weld is spaced apart from the lower edge portion of the side pipe, the distance between the lower weld portion of the annular weld and the upper weld portion of the annular weld is smaller than the distance between the front weld portion of the annular weld and the rear weld portion of the annular weld.

The front support composite pipe fittings mentioned above, because the end face of the front cross pipe is matched with the side wall of the side pipe, the end face of the front cross pipe is easily transitionally connected to the side wall of the side pipe, so that the end face of the front cross pipe and the side wall of the side pipe are firmly combined, and the stress concentration phenomenon can be avoided, so that a larger load can be supported. In addition, because the lower side weld part of the annular weld is spaced from the lower edge of the side pipe, the distance between the lower side weld part of the annular weld and the upper side weld part of the annular weld is smaller than the distance between the front side weld part of the annular weld and the rear side weld part of the annular weld, so that on the one hand, the end face of the front cross pipe and the side wall of the side pipe can be firmly combined, and on the other hand, the annular weld can be as far away from the lower edge of the side pipe as possible, so that the lower edge of the side pipe is less affected by the heat of the annular weld, thereby avoiding the undesirable phenomenon that the lower edge of the side pipe is prone to brittle cracking under the action of external force.

In one of the embodiments, the projection of the end face of the front cross tube on a plane perpendicular to the axial direction of the front cross tube is elliptical, circular or teardrop-shaped; or, the interval between the lower weld of the annular weld and the upper weld of the annular weld gradually increases and then gradually decreases in the axial extension direction of the side tube; or, the angle between the weld point on the lower weld of the annular weld closest to the lower edge of the side tube and the corresponding nearest point on the lower edge of the side tube about the axis of the side tube is 30 to 60 degrees.

In one embodiment, the angle between the weld point on the upper weld portion of the annular weld closest to the upper edge portion of the side tube and the corresponding nearest point on the upper edge portion of the side tube about the axis of the side tube is 30 degrees to 60 degrees.

In one embodiment, the end side wall of the front cross tube smoothly transitions to the side wall of the side tube.

In one embodiment, the side wall of the end of the front cross tube facing the main tube is a first inclined wall inclined relative to the axial direction of the front cross tube, and the first inclined wall is smoothly connected to the side wall of the side tube; the side wall of the end of the front cross tube facing away from the main tube is a second inclined wall inclined relative to the axial direction of the front cross tube, and the second inclined wall is smoothly connected to the side wall of the side tube.

In one embodiment, the front cross tube includes a first cross tube split and a second cross tube split; the first cross tube split is connected to the second cross tube split, the first cross tube split is located above the second cross tube split, and the tube wall thickness of the first cross tube split is greater than the tube wall thickness of the second cross tube split.

In one embodiment, the first transverse tube split body and the second transverse tube split body are both integrally formed by stamping; the first transverse tube split body and the second transverse tube split body are connected by welding.

In one embodiment, the bottom end of the main pipe is connected to the middle part of the front transverse pipe; the end of the front transverse pipe is connected to the curved pipe section of the side pipe.

A vehicle frame comprises the front support combined pipe member.

The above-mentioned frame includes the front support combined pipe fitting, and its technical effect is brought by the front support combined pipe fitting. The beneficial effect is the same as that of the front support combined pipe fitting, and will not be repeated.

A scooter comprises the front supporting combined pipe member.

The above-mentioned scooter, since it includes the front support combined pipe fitting, its technical effect is brought by the front support combined pipe fitting, and its beneficial effect is the same as that of the front support combined pipe fitting, which will not be described in detail.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a front support assembly pipe according to an embodiment of the present invention when viewed from bottom;

FIG2 is a schematic structural diagram of a front support assembly pipe according to an embodiment of the present invention from one viewing angle;

FIG3 is a schematic structural diagram of a front support assembly pipe according to an embodiment of the present invention from another viewing angle;

FIG4 is an exploded schematic diagram of a front cross tube in a front support assembly pipe member according to an embodiment of the present invention;

FIG5 is a schematic structural diagram of an end surface of a front transverse tube in a front support assembly pipe member according to one embodiment of the present invention;

6 is a schematic structural diagram of an end surface of a front cross tube in a front support assembly pipe member according to another embodiment of the present invention;

7 is a schematic structural diagram of the end surface of the front cross tube in the front support assembly pipe according to another embodiment of the present invention;

FIG8 is a schematic cross-sectional view of the middle portion of the front cross tube in the front support assembly pipe according to one embodiment of the present invention;

9 is a schematic diagram of a top view of the structure of a front support assembly pipe member after the front transverse pipe and the side pipe are connected according to an embodiment of the present invention;

FIG10 is a diagram showing the stress effects of the front cross tube and the side tube during use of a conventional scooter;

FIG. 11 is a diagram showing the stress effects of the front cross tube and the side tubes during use of the scooter according to an embodiment of the present invention.

Reference numerals:

10. Main pipe, 20. Side pipe, 21. Lower edge, 22. Upper edge, 30. Front transverse pipe, 31. First transverse pipe split, 32. Second transverse pipe split, 33. First inclined wall, 34. Second inclined wall, 40. Weld; 41. Lower weld; 411. First weld section; 412. Second weld section; 42. Upper weld; 421. Smooth convex seam; 422. Smooth concave seam.

DETAILED DESCRIPTION

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

In the description of the present invention, it should be understood that when an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be intermediate elements at the same time. On the contrary, when an element is said to be "directly" connected to another element, there are no intermediate elements.

Generally, when the outer diameters of the front cross tube and the side tube are close, the overlap weld between the side tube and the front cross tube will extend to the lower edge of the side tube where the bending stress is greater. The material in this area is closer to the weld and is easily affected by the heat of the weld and becomes brittle, which causes the lower edge of the side tube to easily suffer from brittle cracking under the action of external force.

In addition, due to the deformation of the material during the forming of the bent section of the side tube, the radial cross-section of the bent section of the side tube changes from a circle to an ellipse, while the edges at both ends of the front cross tube are formed by punching and are cylindrical surfaces. Therefore, the gap at the overlap between the side tube and the front cross tube is large, the quality of the weld is difficult to control, and the bonding strength between the side tube and the front cross tube is poor.

In one embodiment, referring to FIG. 1 , FIG. 2 and FIG. 11 , a front support combined pipe fitting includes a main pipe 10, two side pipes 20 and a front cross pipe 30. The two side pipes 20 are connected to the main pipe 10. The two ends of the front cross pipe 30 are respectively connected to the two side pipes 20, the end surface of the front cross pipe 30 is matched with the side wall of the side pipe 20, and the end surface of the front cross pipe 30 is welded to the side wall of the side pipe 20 to form an annular weld 40. The lower side weld 41 of the annular weld 40 is spaced from the lower edge 21 of the side pipe 20, and the distance between the lower side weld 41 of the annular weld 40 and the upper side weld 42 of the annular weld 40 is smaller than the distance between the front side weld of the annular weld 40 and the rear side weld of the annular weld 40.

It should be explained that the lower weld 41 portion, the upper weld 42 portion, the front weld portion and the rear weld portion of the annular weld 40 respectively refer to that when the scooter is normally placed on a horizontal ground, the lower portion of the annular weld 40 is the lower weld 41 portion, the upper portion is the upper weld 42 portion, the portion close to the main pipe 10 is the front weld portion, and the portion far from the main pipe 10 is the rear weld portion.

The above-mentioned front support combined pipe fitting, since the end face of the front cross tube 30 is consistent with the side wall of the side tube 20, the end face of the front cross tube 30 is easily transitionally connected to the side wall of the side tube 20, so that the end face of the front cross tube 30 and the side wall of the side tube 20 are firmly connected and stress concentration can be avoided, thereby being able to withstand a larger load. In addition, since the lower weld 41 of the annular weld 40 is spaced apart from the lower edge 21 of the side tube 20, the distance between the lower weld 41 of the annular weld 40 and the upper weld 42 of the annular weld 40 is smaller than the distance between the front weld 40 and the rear weld 40. This allows the end face of the front cross tube 30 to be firmly bonded to the side wall of the side tube 20, and allows the annular weld 40 to be as far away from the lower edge 21 of the side tube 20 as possible. This allows the lower edge 21 of the side tube 20 to be less affected by the heat of the annular weld 40, thereby avoiding the undesirable phenomenon that the lower edge 21 of the side tube 20 is prone to brittle cracking under the action of external force.

In one embodiment, referring to FIG. 5 to FIG. 8 , the projection of the end face of the front transverse tube 30 on a plane perpendicular to the axis direction of the front transverse tube 30 is an ellipse, a circular groove or a teardrop shape. Thus, the projection of the shape of the annular weld 40 formed between the end face of the front transverse tube 30 and the side wall of the side tube 20 on a plane perpendicular to the axis direction of the front transverse tube 30 is an ellipse, a circular groove or a teardrop shape, thereby, on the one hand, making the end face of the front transverse tube 30 and the side wall of the side tube 20 firmly bonded, and on the other hand, making the annular weld 40 as far away from the lower edge portion 21 of the side tube 20 as possible, so that the lower edge portion 21 of the side tube 20 is less affected by the heat of the annular weld 40, thereby avoiding the undesirable phenomenon that the lower edge portion 21 of the side tube 20 is easily brittle and cracked under the action of external force. Among them, the teardrop shape, as shown in FIG. 5 , can be understood as being formed by combining a part of the lines of the long ellipse and the semicircular lines. The circular groove shape is shown in FIG6 , which can be understood as the shape of the four right angles of the rectangle being chamfered. The oval shape is shown in FIG7 . In addition, the cross-sectional schematic diagram of the middle part of the front cross tube 30 is shown in FIG8 , which is a circular shape, that is, the middle part of the front cross tube 30 is a circular tube.

It can be understood that the annular weld 40 corresponds to the portion where the end face of the front cross tube 30 contacts the side wall of the side tube 20. In one embodiment, the interval between the lower weld of the annular weld 40 and the upper weld of the annular weld 40 gradually increases and then gradually decreases in the axial extension direction of the side tube 20. In this way, the end face of the front cross tube 30 is easily and evenly transitioned to the side wall of the side tube 20, so that the end face of the front cross tube 30 and the side wall of the side tube 20 are firmly combined, and stress concentration can be avoided, so that a greater load can be supported. In addition, the lower edge portion 21 refers to the portion of the side wall of the side tube 20 that is closest to the ground in the circumferential surface direction of the side wall of the side tube 20 when the scooter is normally placed on the horizontal ground; correspondingly, the upper edge portion 22 refers to the portion of the side wall of the side tube 20 that is farthest from the ground in the circumferential surface direction of the side wall of the side tube 20.

In one embodiment, please refer to FIG. 2 again, the angle between the weld point closest to the lower edge 21 of the side tube 20 on the lower side weld 41 of the annular weld 40 and the corresponding closest point on the lower edge 21 of the side tube 20 about the axis of the side tube 20 is 30 to 60 degrees. In this way, on the one hand, the annular weld 40 can be ensured to be as far away from the lower edge 21 of the side tube 20 as possible, so that the lower edge 21 of the side tube 20 is less affected by the heat of the annular weld 40, thereby avoiding the undesirable phenomenon that the lower edge 21 of the side tube 20 is prone to brittle cracking under the action of external force; on the other hand, it can also ensure that the end face of the front cross tube 30 and the side wall of the side tube 20 are more effectively combined.

Further, the angle between the weld point closest to the lower edge 21 of the side tube 20 on the lower weld 41 of the annular weld 40 and the corresponding nearest point on the lower edge 21 of the side tube 20 with respect to the axis of the side tube 20 is 40 to 50 degrees. Specifically, the angle between the weld point closest to the lower edge 21 of the side tube 20 on the lower weld 41 of the annular weld 40 and the corresponding nearest point on the lower edge 21 of the side tube 20 with respect to the axis of the side tube 20 is 45 degrees.

In one embodiment, referring to Fig. 1 to Fig. 3, in order to make the upper weld 42 of the annular weld 40 as far away from the upper edge 22 of the side tube 20 as possible, similar to the setting mode of the lower weld 41 of the annular weld 40, the angle between the weld point closest to the upper edge 22 of the side tube 20 on the upper weld 42 of the annular weld 40 and the corresponding nearest point on the upper edge 22 of the side tube 20 about the axis of the side tube 20 is 30 to 60 degrees. In this way, the annular weld 40 can be made as far away from the upper edge 22 of the side tube 20 as possible, so that the upper edge 22 of the side tube 20 is less affected by the heat of the annular weld 40, thereby avoiding the undesirable phenomenon that the upper edge 22 of the side tube 20 is prone to brittle cracking under the action of external force.

Further, referring to Figures 1 to 3, the angle between the weld point on the upper weld 42 of the annular weld 40 that is closest to the upper edge 22 of the side tube 20 and the corresponding nearest point on the upper edge 22 of the side tube 20 with respect to the axis of the side tube 20 is 40 to 50 degrees. Specifically, the angle between the weld point on the upper weld 42 of the annular weld 40 that is closest to the upper edge 22 of the side tube 20 and the corresponding nearest point on the upper edge 22 of the side tube 20 with respect to the axis of the side tube 20 is 45 degrees.

In one embodiment, referring to Figures 1 to 3, the end sidewall of the front cross tube 30 smoothly transitions to the sidewall of the side tube 20. In this way, stress concentration is not likely to occur at the connection between the end sidewall of the front cross tube 30 and the sidewall of the side tube 20 when subjected to external force, that is, no fracture phenomenon will occur.

Furthermore, the side wall of the end of the front cross tube 30 facing the main tube 10 is a first inclined wall 33 inclined relative to the axial direction of the front cross tube 30, and the first inclined wall 33 is smoothly connected to the side wall of the side tube 20. The side wall of the end of the front cross tube 30 facing away from the main tube 10 is a second inclined wall 34 inclined relative to the axial direction of the front cross tube 30, and the second inclined wall 34 is smoothly connected to the side wall of the side tube 20. In this way, the connection between the end side wall of the front cross tube 30 and the side wall of the side tube 20 is not prone to stress concentration when subjected to external force, so that no fracture phenomenon occurs.

Furthermore, the arcuate convex surface of the second inclined wall 34 faces the side wall of the side tube 20, and the angle between the second inclined wall 34 and the side wall of the side tube 20 gradually decreases in the direction close to the side tube 20. In this way, since the arcuate convex surface of the second inclined wall 34 faces the side wall of the side tube 20, the angle between the second inclined wall 34 and the side wall of the side tube 20 gradually decreases in the direction close to the side tube 20. On the one hand, it can be better fitted to the side tube 20; on the other hand, compared with the traditional structure, the stress concentration position is changed, so that the stress concentration area B avoids the area where the weld 40 is located, and the stress concentration area B is prevented from overlapping or partially overlapping or approaching the area where the weld 40 is located (as shown in FIG. 11), thereby avoiding the defect of brittle cracking of the side tube 20 due to stress concentration.

In one embodiment, please refer to FIG. 9 , the upper weld 42 includes a smooth convex seam 421 and a smooth concave seam 422 sequentially arranged along the axial direction of the side tube 20. In this way, the side tube wall where the lower weld 41 of the end face of the front cross tube 30 is located and the side tube wall where the upper weld 42 is located can tightly hold the side wall of the side tube 20. On the one hand, the combination is firm, and on the other hand, compared with the traditional structure, the stress concentration position is changed, so that the stress concentration area B avoids the area where the weld 40 is located, and the stress concentration area B is prevented from overlapping or partially overlapping or approaching the area where the weld 40 is located, thereby avoiding the defect of brittle cracking of the side tube 20 due to stress concentration.

It should be explained that the "smooth" in this embodiment refers to a gradual change, a gentle change, not a sudden change. That is, for the smooth convex seam 421 or the smooth concave seam 422, a fold line seam is obviously excluded, and it can be, for example, an arc seam, a wavy seam, an elliptical seam, etc.

Further, referring to FIG. 9 , the lower weld 41 includes a first weld section 411 and a second weld section 412 which are sequentially arranged along the axis direction of the side tube 20. One end of the first weld section 411 is connected to the smooth convex seam 421, the other end of the first weld section 411 is connected to one end of the second weld section 412, and the other end of the second weld section 412 is connected to the smooth concave seam 422. When the front support assembly pipe is placed on a horizontal plane in a normal posture, looking from top to bottom along the vertical direction, the upper weld 42 intersects with the lower weld 41, the smooth convex seam 421 is closer to the axis of the side tube 20 relative to the first weld section 411, and the second weld section 412 is closer to the axis of the side tube 20 relative to the smooth concave seam 422. In this way, the side tube wall where the lower weld 41 of the end face of the front cross tube 30 is located and the side tube wall where the upper weld 42 is located tightly hold the side wall of the side tube 20. On the one hand, the combination is firm, and on the other hand, compared with the traditional structure, the stress concentration position is changed, so that the stress concentration area B avoids the area where the weld 40 is located, avoiding the stress concentration area B and the area where the weld 40 are located from overlapping or partially overlapping or approaching, thereby avoiding the defect of brittle cracking of the side tube 20 due to stress concentration.

Further, please refer to Figure 9. The first inclined wall 33 of the front cross tube 30 is equivalent to a flange structure that is turned up in the axial direction away from the cross tube portion 31. The flange structure supports the side tube 20, changes the stress concentration position, and makes the stress concentration area B avoid the area where the weld 40 is located, avoiding the stress concentration area B and the area where the weld 40 are located from overlapping or partially overlapping or approaching, thereby avoiding the defect of brittle cracking of the side tube 20 due to stress concentration.

In one embodiment, referring to FIG4 , the front cross tube 30 includes a first cross tube body 31 and a second cross tube body 32. The first cross tube body 31 is connected to the second cross tube body 32, the first cross tube body 31 is located above the second cross tube body 32, and the wall thickness of the first cross tube body 31 is greater than the wall thickness of the second cross tube body 32. In this way, the requirements of the front support combined pipe for weight and strength stiffness are taken into account at the same time.

Furthermore, the first transverse tube sub-body 31 and the second transverse tube sub-body 32 are both integrally formed by stamping. In addition, specifically, the first transverse tube sub-body 31 and the second transverse tube sub-body 32 are connected by welding.

In one embodiment, referring to Figures 1 to 3, the bottom end of the main pipe 10 is connected to the middle of the front cross pipe 30. In this way, the front support combined pipe structure has good stability and can withstand a large load.

In addition, in order to maximize the space under the pedal, the front cross tube 30 is often arranged at a relatively forward position, and the two ends of the front cross tube 30 are respectively overlapped on the curved sections of the two side tubes 20. That is, the ends of the front cross tube 30 are connected to the curved sections of the side tubes 20.

In one embodiment, a vehicle frame includes the front support composite pipe member described in any one of the above embodiments.

The above-mentioned frame includes the front support combined pipe fitting, and its technical effect is brought by the front support combined pipe fitting. The beneficial effect is the same as that of the front support combined pipe fitting, and will not be repeated.

In one embodiment, a scooter comprises the front support assembly pipe member described in any one of the above embodiments.

The above-mentioned scooter, since it includes the front support combined pipe fitting, its technical effect is brought by the front support combined pipe fitting, and its beneficial effect is the same as that of the front support combined pipe fitting, which will not be described in detail.

The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims (10)

1. A front support assembly pipe, characterized by comprising: A main pipe and two side pipes, wherein the two side pipes are connected to the main pipe; A front cross tube, wherein both ends of the front cross tube are respectively connected to the two side tubes, the end face of the front cross tube coincides with the side wall of the side tube, the end face of the front cross tube is welded to the side wall of the side tube to form an annular weld, the lower weld portion of the annular weld is spaced apart from the lower edge portion of the side tube, the distance between the lower weld portion of the annular weld and the upper weld portion of the annular weld is smaller than the distance between the front weld portion of the annular weld and the rear weld portion of the annular weld; the interval between the lower weld of the annular weld and the upper weld of the annular weld first gradually increases and then gradually decreases in the axial extension direction of the side tube; the angle between the weld point on the lower weld portion of the annular weld closest to the lower edge portion of the side tube and the corresponding nearest point on the lower edge portion of the side tube with respect to the axis of the side tube is 30 to 60 degrees. 2. The front support assembly pipe fitting according to claim 1 is characterized in that the projection of the end face of the front cross tube on a plane perpendicular to the axial direction of the front cross tube is an ellipse, a circular groove or a teardrop shape; and/or the angle between the weld point on the lower side weld of the annular weld closest to the lower edge of the side tube and the corresponding nearest point on the lower edge of the side tube with respect to the axis of the side tube is 40 degrees to 50 degrees. 3. The front support assembly pipe fitting according to claim 1 is characterized in that the angle between the weld point on the upper weld portion of the annular weld closest to the upper edge portion of the side tube and the corresponding nearest point on the upper edge portion of the side tube with respect to the axis of the side tube is 30 degrees to 60 degrees. 4. The front support combined pipe member according to claim 1, characterized in that the end side wall of the front cross pipe smoothly transitions to the side wall of the side pipe. 5. The front support assembly pipe according to claim 4 is characterized in that the side wall of the end of the front cross tube facing the main tube is a first inclined wall inclined relative to the axial direction of the front cross tube, and the first inclined wall is smoothly connected to the side wall of the side tube; the side wall of the end of the front cross tube facing away from the main tube is a second inclined wall inclined relative to the axial direction of the front cross tube, and the second inclined wall is smoothly connected to the side wall of the side tube. 6. The front support assembly pipe according to claim 1 is characterized in that the front cross tube includes a first cross tube split and a second cross tube split; the first cross tube split is connected to the second cross tube split, the first cross tube split is located above the second cross tube split, and the tube wall thickness of the first cross tube split is greater than the tube wall thickness of the second cross tube split. 7. The front support combined pipe member according to claim 6, characterized in that the first transverse pipe split body and the second transverse pipe split body are both integrally formed by stamping; and the first transverse pipe split body and the second transverse pipe split body are connected by welding. 8. The front support combined pipe fitting according to any one of claims 1 to 7, characterized in that the bottom end of the main pipe is connected to the middle of the front cross pipe; and the end of the front cross pipe is connected to the curved pipe section of the side pipe. 9. A vehicle frame, characterized by comprising the front support composite pipe member according to any one of claims 1 to 8. 10. A scooter, characterized by comprising the front support assembly pipe member according to any one of claims 1 to 8.