JP6972399B2 - Manufacturing method of handle pipe for saddle-type vehicle - Google Patents

Description

The present invention relates to a handle for a saddle-mounted vehicle. The present invention also relates to a method for manufacturing a handle pipe for a saddle-mounted vehicle or a saddle-mounted vehicle.

A handle for a saddle-mounted vehicle is configured to include a handle pipe and a handle grip. A handle pipe (sometimes referred to as a "handlebar") is a tubular member made primarily of metal material. The handle grip is a member gripped by the rider and is attached to both ends of the handle pipe.

There are two types of handles for saddle-mounted vehicles, one is a type in which the outer diameter of the handle pipe is the same as a whole, and the other is a type in which the outer diameter of the handle pipe is larger than both ends in the central portion. The latter type is called a tapered handle and is used, for example, in off-road motorcycles. Patent Document 1 discloses a handle pipe for a tapered handle.

In the handle pipe of Patent Document 1, the wall thickness at both ends is larger than the wall thickness at the center. For example, when a handle pipe is manufactured (diameter reduction at both ends) using swaging, such a wall thickness distribution is obtained.

U.S. Pat. No. 5,117,708

Recently, there is a demand for further weight reduction of saddle-mounted vehicles such as motorcycles. The inventor of the present application has examined the weight reduction of the handle from various viewpoints. Since the outer diameter of the handle pipe is restricted by the standard, we tried to reduce the weight by thinning the handle pipe.

However, according to the study of the inventor of the present application, it has been found that if the weight is reduced by thinning the handle pipe, the ride quality is changed, which may cause fatigue of the rider.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce the weight of a handle for a saddle-mounted vehicle while reducing the fatigue of a rider.

The handle for a saddle-type vehicle according to an embodiment of the present invention is a first handle grip and a second handle grip gripped by a rider, and a tubular handle pipe, which is the first handle grip and the second handle grip. A steering wheel for a saddle-type vehicle provided with a supporting handle pipe, wherein the handle pipe is located at the center in the longitudinal direction, and is located at a mounting portion to be attached to the steering rotating device and one end in the longitudinal direction. Located between the first grip portion to which the first handle grip is attached and the second grip portion to which the second handle grip is attached, which is located at the other end in the longitudinal direction, and between the attachment portion and the first grip portion. The mounting portion is located between the mounting portion and the second grip portion, which extends from one end of the mounting portion to one end of the first grip portion in a direction different from that of the mounting portion. It has a second bent portion extending from the other end to one end of the second grip portion in a direction different from that of the mounting portion, and the first grip portion has a first overlapping region overlapping the first handle grip. It has a first non-superimposed region located between the first superposed region and the first bent portion and does not overlap the first handle grip, and the second grip portion overlaps the second handle grip. It has a second superposed region, a second non-superimposed region located between the second superposed region and the second bent portion and does not overlap the second handle grip, and the first non-superimposed region of the first grip portion. Each of the superposed region and the second non-superimposed region of the second grip portion includes a thick portion having a wall thickness equal to or larger than the wall thickness of the mounting portion, and the first superposed region of the first grip portion and the said Each of the second overlapping regions of the second grip portion includes a thin wall portion having a wall thickness smaller than the wall thickness of the thick wall portion.

In certain embodiments, the wall thickness of the thin portion is smaller than the wall thickness of the attachment portion.

In one embodiment, in the thin-walled portion, the mass of each of the first superimposing region of the first grip portion and the second superimposing region of the second grip portion is 12% or less of the mass of the entire handle pipe. It is formed to be.

In a certain embodiment, the boundary between the first superimposing region and the first non-superimposing region in the first grip portion is referred to as a first boundary, and the second superimposing region and the second non-superimposing region in the second grip portion are referred to as a first boundary. When the boundary with the region is referred to as a second boundary, the thin portion of the first overlapping region is formed from the other end of the first grip portion to a predetermined first position, and the second overlapping region is said to have a predetermined position. The thin portion is formed from the other end of the second grip portion to a predetermined second position, and the distance between the first position and the first boundary and the distance between the second position and the second boundary are , 30 mm or less, respectively.

In certain embodiments, the thin portion is formed substantially over each of the first superposed region and the second superposed region.

In one embodiment, the wall thickness of the thin wall portion is smaller than the wall thickness of the thick wall portion over the entire circumferential direction.

In one embodiment, the wall thickness of the thin wall portion is partially smaller than the wall thickness of the thick wall portion in the circumferential direction.

In certain embodiments, the wall thickness in the thin portion is approximately the same and symmetric along the longitudinal direction of the handle pipe.

In certain embodiments, the wall thickness in the thin portion varies along the longitudinal direction of the handle pipe.

In certain embodiments, the saddle-mounted vehicle handle does not include a weight mounted so as to be located within the first grip and the second grip.

In certain embodiments, the handle pipe is made of a non-ferrous metal material.

In one embodiment, the outer diameter of the attachment portion of the handle pipe is larger than the outer diameter of each of the first grip portion and the second grip portion.

In one embodiment, the flatness in the central portion of each of the first bent portion and the second bent portion is 5% or less.

The saddle-type vehicle according to the embodiment of the present invention includes a handle for a saddle-type vehicle having any of the above-described configurations.

The method for manufacturing a steering wheel pipe for a saddle-mounted vehicle according to an embodiment of the present invention includes a mounting portion located in the central portion in the longitudinal direction and attached to a steering rotating device, a first grip portion located at one end in the longitudinal direction, and a longitudinal portion. Located between the second grip portion located at the other end of the direction and the mounting portion and the first grip portion, from one end of the mounting portion to one end of the first grip portion in a direction different from the mounting portion. A second bending portion located between the extending first bending portion and the mounting portion and the second grip portion, and extending from the other end of the mounting portion to one end of the second grip portion in a direction different from the mounting portion. A step (A) of preparing a tubular workpiece made of a metal material, and the first grip portion and the second grip portion of the workpiece, which are methods for manufacturing a handle pipe for a saddle-mounted vehicle. After the step (B) of processing to make the outer diameter of the region to be the grip portion smaller than the outer diameter of the region to be the mounting portion and the step (B), the workpiece is subjected to a solution treatment. This includes a step (C) to be performed and a step (D) in which the workpiece is bent after the step (C).

In a certain embodiment, the workpiece prepared in the step (A) is a workpiece produced by an extrusion method.

In one embodiment, the method for manufacturing a handle pipe for a saddle-mounted vehicle further includes a step (E) of thinning a part of a region to be the first grip portion and the second grip portion, and the first method is described. Each of the 1 grip portion and the second grip portion includes a thick portion having a wall thickness equal to or larger than the wall thickness of the mounting portion and a thin portion having a wall thickness smaller than the wall thickness of the thick portion.

In certain embodiments, the step (E) is performed by machining after the step (B).

In certain embodiments, the step (B) is performed by swaging, and in the step (B), the step (E) is also performed.

In the handle for a saddle-mounted vehicle according to the embodiment of the present invention, each of the first grip portion and the second grip portion of the handle pipe has a thick portion having a wall thickness equal to or larger than the thickness of the mounting portion and a thick portion. It includes a thin portion having a wall thickness smaller than the wall thickness. Specifically, the thick portion includes a first non-overlapping region (a region that does not overlap with the first handle grip) of the first grip portion and a second non-superimposition region (a region that does not overlap with the second handle grip) of the second grip portion. ), And specifically, the thin-walled portion is formed in the first overlapping region of the first grip portion (the region overlapping the first handle grip) and the second overlapping region of the second grip portion (in the second handle grip). It is formed in the overlapping area). Since the first grip portion and the second grip portion include the thick portion, a sufficient sense of rigidity can be ensured. Further, since the first grip portion and the second grip portion include the thin-walled portion, the weight can be reduced as compared with the case where the entire first grip portion and the second grip portion are thick-walled portions, for example. .. Further, a thick portion is arranged in a region located relatively inside the first grip portion and the second grip portion (first non-superimposed region and second non-superimposed region), and a region located relatively outside (first non-superimposed region and second non-superimposed region). By arranging the thin-walled portion in the first superposed region and the second superposed region), the feeling of pushing up can be reduced. Therefore, the rider's fatigue can be suppressed. As described above, according to the embodiment of the present invention, the weight of the steering wheel for a saddle-mounted vehicle can be reduced while reducing the fatigue of the rider.

If the wall thickness of the thin portion is smaller than the wall thickness of the mounting portion, further weight reduction can be realized.

From the viewpoint of more reliably obtaining a sufficient weight reduction effect and a reduction in the feeling of pushing up, the thin-walled portion has a handle pipe in which the masses of the first superposed region of the first grip portion and the second superposed region of the second grip portion are respectively. It is preferably formed so as to be 12% or less of the total mass.

Further, from the viewpoint of weight reduction, it is preferable that the thin portion is formed as wide (large) as possible in each of the first superimposed region and the second superimposed region. For example, the thin portion of the first superimposed region may be formed from the end of the first grip portion (the end opposite to the first bent portion) to a predetermined position (first position), or the second superimposed region may be formed. The thin portion of the region may be formed from the end of the second grip portion (the end opposite to the second bent portion) to a predetermined position (second position). When the boundary between the first superposed region and the first non-superimposed region in the first grip portion is called the first boundary, and the boundary between the second superposed region and the second non-superimposed region in the second grip portion is called the second boundary. , The distance between the first position and the first boundary and the distance between the second position and the second boundary are preferably 30 mm or less, respectively.

When the thin portion is formed over substantially the entire first superimposing region and the second superimposing region, it is easier to obtain a sufficient weight reduction effect.

When the wall thickness in the thin wall portion is smaller than the wall thickness of the thick wall portion in the entire circumferential direction (that is, the wall thickness is thinned in the entire circumferential direction), the wall thickness is partially thinned in the circumferential direction. Compared to, the weight reduction effect is high.

When the wall thickness in the thin-walled portion is partially smaller than the wall thickness in the thick-walled portion in the circumferential direction, the bending rigidity of the first grip portion and the second grip portion can be easily adjusted.

The wall thickness in the thin portion may be substantially the same and symmetric along the longitudinal direction of the handle pipe, or may vary along the longitudinal direction of the handle pipe.

The handle for a saddle-mounted vehicle according to the embodiment of the present invention does not have to include a weight attached so as to be located in the first grip portion and the second grip portion.

The embodiment of the present invention has great significance when the handle pipe is formed of a non-ferrous metal material. This is because when the handle pipe is formed from an iron-based material such as steel, the wall thickness is small, and it is difficult to reduce the weight by reducing the wall thickness. On the other hand, when the handle pipe is made of a non-ferrous metal material, the wall thickness tends to increase as a whole when trying to secure the required rigidity under the restriction of the shape due to the riding posture of the rider. According to the embodiment of the present invention, by making good use of the relatively thick wall thickness (selectively forming the thin wall portion as described above), the required rigidity is satisfied and the rider's fatigue is reduced. Can be planned.

The embodiment of the present invention can be suitably used for a configuration in which the outer diameter of the attachment portion of the handle pipe is larger than the outer diameter of each of the first grip portion and the second grip portion (so-called "taper handle"). When a handle pipe for a tapered handle is manufactured by, for example, swaging, the wall thickness increases from the center portion (mounting portion) of the handle pipe toward the end portion side. Therefore, the weight of the handle pipe is likely to increase. As in the present invention, since the first grip portion and the second grip portion of the handle pipe include a thin-walled portion, weight reduction in the tapered handle can be suitably realized.

From the viewpoint of uniformity of rigidity, it is preferable that the flatness of the first bent portion and the second bent portion is small, and specifically, the flatness of the central portion of the first bent portion and the second bent portion is 5. % Or less is preferable.

In the production method according to the embodiment of the present invention, the solution treatment is performed before the bending process. When the solution treatment is performed after the bending process, high temperature holding and quenching are performed after molding into the product shape, so that the deformation due to the heat treatment becomes large. Therefore, it is necessary to perform a straightening treatment after the solution treatment. On the other hand, in the production method of the present invention, the solution treatment is performed before the bending process, so that the straightening treatment becomes unnecessary. Further, since the bending process is performed after the workpiece is hardened to some extent by the solution heat treatment, the cross-sectional shapes of the first bent portion and the second bent portion are less likely to change. Therefore, the flatness of the first bent portion and the second bent portion can be reduced.

The prepared workpiece is preferably one produced by an extrusion method (extruded material), and more preferably one produced by a hydrostatic pressure extrusion method (hydrostatic pressure extruded material). The extruded material has excellent wall thickness uniformity. The hydrostatic pressure extruded material is superior in strength to a general extruded material.

A part of the region to be the first grip portion and the second grip portion may be thinned. Each of the first grip portion and the second grip portion includes a thick portion having a wall thickness equal to or larger than the wall thickness of the mounting portion and a thin portion having a wall thickness smaller than the wall thickness of the thick portion. It is possible to reduce the weight and reduce the rider's fatigue.

The step of thinning a part of the region to be the first grip portion and the second grip portion can be preferably performed by, for example, machining.

Further, in the manufacturing method according to the embodiment of the present invention, a process (reduction) in which the outer diameter of the region to be the first grip portion and the second grip portion of the workpiece is made smaller than the outer diameter of the region to be the mounting portion. Diameter process) is included. This diameter reduction step can be preferably performed by, for example, swaging. In that case, in the diameter reduction step, a part of the region to be the first grip portion and the second grip portion can be thinned.

According to the embodiment of the present invention, the weight of the steering wheel for a saddle-mounted vehicle can be reduced while reducing the fatigue of the rider.

It is a left side view which shows the schematic structure of the motorcycle (saddle type vehicle) 1 by embodiment of this invention. (A), (b) and (c) are a view of the handlebar 20 of the motorcycle 1 from above, a view from the left side, and a view from diagonally above the rear, respectively. (A), (b) and (c) are a view of the handle pipe 22 of the handle 20 from above, a view from the left side, and a view from diagonally rearward. It is a figure which shows the cross section (the cross section along the longitudinal direction of the handle pipe 22) of the attachment part AP of the handle pipe 22, the 1st grip part GP1 and the 2nd grip part GP2. (A) and (b) are sectional views showing an example of the structure of the 1st grip part GP1 and the 2nd grip part GP2. (A) and (b) are sectional views showing an example of the structure of the 1st grip part GP1 and the 2nd grip part GP2. (A) and (b) are sectional views showing an example of the structure of the 1st grip part GP1 and the 2nd grip part GP2. (A) and (b) are sectional views showing an example of the structure of the 1st grip part GP1 and the 2nd grip part GP2. (A) and (b) are sectional views showing an example of the structure of the 1st grip part GP1 and the 2nd grip part GP2. (A), (b) and (c) are diagrams showing an example of the shapes of the superimposed regions GP1a and GP2a in the cross section orthogonal to the longitudinal direction of the handle pipe 22. It is a flowchart which shows the example of the manufacturing method of a handle pipe 22. It is a flowchart which shows the manufacturing method of the handle pipe by a reference example. It is a graph which shows the example of the stress-strain curve after annealing and after solution treatment for a workpiece made of an aluminum alloy.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the following embodiments.

(Overall configuration of motorcycle)
FIG. 1 is a left side view showing a schematic configuration of a motorcycle (saddle-mounted vehicle) 1. The motorcycle 1 is a motocross vehicle that is supposed to run on rough terrain. As shown in FIG. 1, the motorcycle 1 includes a vehicle body frame 2, an engine 3, a front wheel 4, a rear wheel 5, a seat seat 6, a fuel tank 7, and a handle 20. In the following description, front, rear, left and right mean front, rear, left and right as seen from the rider (driver) seated in the seat 6 while holding the steering wheel 20.

The vehicle body frame 2 is a cradle type frame and supports the engine 3. The vehicle body frame 2 includes a first main frame 10a and a second main frame 10b, a down frame 11, a first lower frame 12a and a second lower frame 12b, a head pipe 13, a pair of rear arms 14a and 14b, and a first. It has one rear frame 15a and a second rear frame 15b.

The head pipe 13 is arranged at the front portion of the motorcycle 1. The first main frame 10a and the second main frame 10b are arranged side by side in the vehicle width direction (left-right direction). The first main frame 10a and the second main frame 10b extend diagonally downward from the head pipe 13 toward the rear.

The first main frame 10a is located on the left side of the vehicle, and the second main frame 10b is located on the right side of the vehicle. A pivot shaft 16 is provided at the lower ends of the first main frame 10a and the second main frame 10b.

The down frame 11 is connected to the head pipe 13 at a position below the first main frame 10a and the second main frame 10b. The down frame 11 extends downward and rearward from the head pipe 13.

The first lower frame 12a connects the lower end of the down frame 11 and the lower end of the first main frame 10a. The second lower frame 12b connects the lower end of the down frame 11 and the lower end of the second main frame 10b.

According to the above-described configuration, the head pipe 13, the first main frame 10a, the down frame 11 and the first lower frame 12a are connected in a loop when viewed from the left side of the vehicle. Further, when viewed from the right side of the vehicle, the head pipe 13, the second main frame 10b, the down frame 11 and the second lower frame 12b are also connected in a loop shape.

The pair of rear arms 14a and 14b are arranged on the left side and the right side of the vehicle, respectively. The front ends of the pair of rear arms 14a and 14b are attached to the pivot shaft 16, respectively, and are supported by the pivot shaft 16 so as to be swingable up and down. The rear wheels 7 are sandwiched in the vehicle width direction and rotatably attached to the rear ends of the pair of rear arms 14a and 14b.

The first rear frame 15a is located on the left side of the vehicle, and the second rear frame 15b is located on the right side of the vehicle. The front end of the first rear frame 15a is connected to the first main frame 10a, and extends from the first main frame 10a to the rear of the vehicle. The front end of the second rear frame 15b is connected to the second main frame 10b, and extends from the second main frame 10b to the rear of the vehicle.

The head pipe 13 rotatably supports the steering device 30. The steering device 30 can change the traveling direction of the motorcycle 1. The steering device 30 includes a steering rotation device 31 and a steering wheel 20. The steering rotating device 31 includes a steering shaft (not shown), an upper bracket 8, an under bracket 9, a front suspension 17, and a front wheel 4. The upper end of the steering shaft (not shown) arranged in the head pipe 13 is attached to the upper bracket 8, and the lower end is attached to the under bracket 9. The upper bracket 8 and the under bracket 9 hold the upper part of the front suspension 17 by their left and right ends. A front wheel 4 is rotatably attached to the lower end of the front suspension 17. A handle 20 is attached to the upper bracket 8. The steering device 30 is configured such that the steering rotation device 31 rotates around the steering shaft and the direction of the front wheels 4 changes when the rider grips the handle 20 and performs a rotation operation around the steering shaft.

A seat seat 6 is arranged behind the head pipe 13 and above the first main frame 10a and the second main frame 10b. A fuel tank 7 is arranged below the seat 6. The engine 3 is arranged below the first mainframe 10a and the first mainframe 10b and behind the downframe 11.

(Structure of handle)
The configuration of the handle 20 will be described with reference to FIG. 2 (a), (b) and (c) are a view of the handlebar 20 from above, a view from the left side, and a view from diagonally above the rear, respectively. Further, FIGS. 2A, 2B and 2C also show the upper bracket 8.

As shown in FIGS. 2 (a), 2 (b) and 2 (c), the handle 20 includes a pair of handle grips (first handle grip and second handle grip) 21A and 21B, and a handle pipe (“handlebar”). (Sometimes called) 22. The handle 20 may further have a lever (clutch lever, brake lever), a switch unit, and the like, but these are not shown here.

The first handle grip 21A and the second handle grip 21B are gripped by the rider. The first handle grip 21A and the second handle grip 21B are each tubular and are formed of, for example, rubber. A flange portion 21Af and 21Bf are formed at one end (inner end) of each of the first handle grip 21A and the second handle grip 21B.

The handle pipe 22 is tubular (ie, a hollow member) and is typically made of a metallic material. The handle pipe 22 supports the first handle grip 21A and the second handle grip 21B.

The handle pipe 22 has a mounting portion AP, a pair of grip portions (first grip portion and second grip portion) GP1 and GP2, and a pair of bending portions (first bending portion and second bending portion) BP1 and BP2. Have.

The mounting portion AP is located at the central portion in the longitudinal direction of the handle pipe 22. The mounting portion AP extends substantially linearly. The mounting portion AP is a portion to be mounted on the steering rotating device 31. In the illustrated example, the attachment portion AP is attached to the upper bracket 8 by a pair of clamp members 18. The configuration for mounting the mounting portion AP on the steering rotating device 31 is not limited to that exemplified here. For example, the mounting portion AP may be mounted on the steering rotating device 31 by one clamp member.

The first grip portion GP1 is located at one end portion (here, the left end portion) in the longitudinal direction of the handle pipe 22. The first grip portion GP1 extends substantially linearly. The first grip portion GP1 extends in the vehicle width direction in a state where the steering device 30 is directed in the front-rear direction of the vehicle body (hereinafter, referred to as "vehicle straight-ahead state"). Further, in the straight-ahead state of the vehicle, the left end portion of the first grip portion GP1 is located behind and above the mounting portion AP. The first handle grip 21A is attached to the left end portion of the first grip portion GP1.

The second grip portion GP2 is located at the other end portion (here, the right end portion) in the longitudinal direction of the handle pipe 22. The second grip portion GP2 extends substantially linearly. The second grip portion GP2 extends in the vehicle width direction in the vehicle straight-ahead state. Further, in the straight-ahead state of the vehicle, the right end portion of the second grip portion GP2 is located behind and above the mounting portion AP. The second handle grip 21B is attached to the right end portion of the second grip portion GP2.

The first bent portion BP1 is located between the mounting portion AP and the first grip portion GP1. The first bent portion BP1 extends from one end of the mounting portion AP to the right end portion of the first grip portion GP1 in a direction different from that of the mounting portion AP. More specifically, the first bent portion BP1 extends upward and backward. That is, the first bending portion BP1 connects the mounting portion AP and the first grip portion GP1.

The second bent portion BP2 is located between the mounting portion AP and the second grip portion GP2. The second bent portion BP2 extends from the other end of the mounting portion AP to the left end portion of the second grip portion GP2 in a direction different from that of the mounting portion AP. More specifically, the second bent portion BP1 extends upward and backward. That is, the second bending portion BP2 connects the mounting portion AP and the second grip portion GP2.

Here, the outer diameter od1 of the mounting portion AP (see FIG. 2A) is larger than the outer diameter od2 of the grip portions GP1 and GP2. That is, the handle 20 is a so-called tapered handle.

Subsequently, the configuration of the handle pipe 22 included in the handle 20 will be described in more detail with reference to FIG. 3 (a), (b) and (c) are views corresponding to FIGS. 2 (a), (b) and (c), but only the handle pipe 22 is shown.

As shown in FIGS. 3A, 3B and 3C, the first grip portion GP1 has a first superimposing region GP1a and a first non-superimposing region GP1b. The first superimposed region GP1a is an region that overlaps with the first handle grip 21A. The first non-superimposition region GP1b is a region located between the first superimposition region GP1a and the first bending portion BP1 and does not overlap with the first handle grip GP1.

Similarly, the second grip portion GP2 has a second superimposed region GP2a and a second non-superimposed region GP2b. The second superimposed region GP2a is an region that overlaps with the second handle grip 21B. The second non-superimposed region GP2b is a region located between the second superposed region GP2a and the second bent portion BP2 and does not overlap with the second handle grip 21B.

In the following, the first superposed region GP1a and the second superposed region GP2a may be collectively referred to as a “superimposed region”, and the first non-superimposed region GP1b and the second non-superimposed region GP2b are collectively referred to as “non-superimposed region GP2b”. Sometimes called "area".

Here, with reference to FIG. 4, the relationship between the wall thickness of each portion of the handle pipe 22 will be described. FIG. 4 shows a cross section (a cross section along the longitudinal direction of the handle pipe 22) of the mounting portion AP, the first grip portion GP1 and the second grip portion GP2.

Each of the first non-superimposed region GP1b of the first grip portion GP1 and the second non-superimposed region GP2b of the second grip portion GP2 is equal to or larger than the wall thickness t0 of the mounting portion AP (that is, equal to or larger than the wall thickness t0). ) Includes a thick portion p1 having a wall thickness t1.

Further, each of the first superposed region GP1a of the first grip portion GP1 and the second superposed region GP2a of the second grip portion GP2 includes a thin portion p2 having a wall thickness t2 smaller than the wall thickness t1 of the thick portion p1. .. Here, the wall thickness t2 of the thin-walled portion p2 is smaller than the wall thickness t0 of the mounting portion AP.

The wall thickness of the first bent portion BP1 and the second bent portion BP2 is typically equal to or larger than the wall thickness of the mounting portion AP. When the swaging process as described later is used for manufacturing the handle pipe 22, the wall thickness of the first bending portion BP1 increases from the mounting portion AP side toward the first grip portion GP1 side, and similarly, the second bending portion is bent. The wall thickness of the portion BP2 increases from the mounting portion AP side toward the second grip portion GP2 side.

As described above, in the handle 20 of the present embodiment, the grip portions GP1 and GP2 of the handle pipe 22 have a thick portion p1 having a wall thickness t1 equal to or larger than the wall thickness t0 of the mounting portion AP, and the meat of the thick portion p1. It includes a thin portion p2 having a wall thickness t2 smaller than the thickness t1. The thick portion p1 is specifically formed in the non-superimposed regions GP1b and GP2b of the grip portions GP1 and GP2, and the thin-walled portion p2 is specifically formed in the superimposed regions GP1a and GP2a of the grip portions GP1 and GP2. Is formed in. Since the grip portions GP1 and GP2 include the thick portion p1, a sufficient sense of rigidity can be ensured. Further, since the grip portions GP1 and GP2 include the thin-walled portion p2, the weight can be reduced as compared with the case where the entire grip portions GP1 and GP2 are made into the thick-walled portion p1, for example. Further, according to the study of the inventor of the present application, the thick portion p1 is arranged in the regions (first non-superimposition region GP1b and second non-superimposition region GP2b) located relatively inside the grip portions GP1 and GP2, and is relative to each other. It was found that the rider's fatigue can be suppressed by arranging the thin-walled portion p2 in the regions (first superimposed region GP1a and second superimposed region GP2a) located on the outer side. It is considered that the reason why the rider's fatigue can be suppressed is that the wall thickness distribution as described above reduces the feeling of pushing up and provides a suitable feeling of operation.

Here, the result of verification that a suitable operation feeling can be obtained and the reason for the verification will be described.

Table 1 shows the results of trial production of the handles of Examples and Comparative Examples 1 to 3 using an aluminum alloy as a metal material and a verification test of the operation feeling. The verification items are three items: a feeling of pushing up, a feeling of steering, and a feeling of rigidity. In the verification test, the motorcycles equipped with the handles of Examples and Comparative Examples 1 to 3 traveled on a road surface having a gap (unevenness), and the rider evaluated them. For Examples and Comparative Examples 1 to 3, the wall thickness at the mounting portion and the wall thickness at the grip portion are as shown in Table 2. As shown in Table 2, in Comparative Examples 1 to 3, the wall thickness is the same in the entire grip portion (that is, in the superposed region and the non-superimposed region). On the other hand, in the embodiment, the wall thickness in the superposed region (the length along the longitudinal direction is 113 mm) is smaller than the wall thickness in the non-superimposed region. In addition, Table 2 also shows the weight of the entire handle pipe and the weight of the overlapping region of the grip portion for Examples and Comparative Examples 1 to 3.

The evaluation of the operational feeling was performed with reference to Comparative Example 1. In Comparative Example 1, although the handle pipe is the heaviest, a feeling of operation without any problem is obtained. Although Comparative Example 2 is lighter than Comparative Example 1, it is inferior to Comparative Example 1 in terms of a feeling of pushing up and a feeling of rigidity. Comparative Example 3 is also lighter than Comparative Example 1, but is inferior to Comparative Example 1 in terms of a feeling of pushing up and a feeling of rigidity.

On the other hand, in the example, the weight is significantly reduced as compared with the comparative example 1, and the feeling of pushing up and the feeling of rigidity are almost the same as those of the comparative example 1, and the feeling of steering is the same as that of the comparative example 1. Better than.

As described above, it was confirmed that the overlapping regions GP1a and GP2a of the grip portions GP1 and GP2 include the thin-walled portion p2, so that a suitable operation feeling can be obtained while reducing the weight. The reason why the feeling of rigidity, the feeling of pushing up, and the feeling of steering are improved by thinning the overlapped regions GP1a and GP2a is presumed as follows.

[Rigidity]
The rider senses the displacement behavior of the grip when a load is applied to the grip via the handle grip. The rider does not feel that the displacement with respect to the load is too small or too large as a preferable displacement behavior, and that the displacement with respect to the load is moderate as a preferable displacement behavior. Therefore, by arranging the thin-walled portion in the superposed region of the grip portion and arranging the thick-walled portion in the non-superimposed region, an appropriate displacement can be realized and a preferable feeling of rigidity can be obtained.

[Feeling of pushing up]
The steering wheel vibrates when a motorcycle travels on a road surface with a gap. The rider feels the vibration behavior of the grip as a feeling of pushing up. If the vibration is large or the vibration decays slowly, the rider feels a great push-up feeling. The logarithmic decrement δ is known as a parameter representing vibration damping. The logarithmic decrement δ is expressed by the following equation using the damping ratio ζ.
δ = 2πζ

The attenuation ratio ζ is the ratio of the attenuation coefficient C to the critical attenuation coefficient C _C as expressed by the following equation.
ζ = C / C _C

The critical damping coefficient C _C is expressed by the following equation using the mass m of the mass point and the spring constant k.
_C C = 2 ^{(mk) 1/2}

Therefore, it can be seen that the smaller the mass m and the smaller the spring constant k, the larger the logarithmic decrement δ and the faster the damping.

When the above items are applied to the vibration of the handle, it can be said that if the mass of the end portion (that is, the overlapping portion) of the grip portion is small and the rigidity is low, the vibration is damped faster. Therefore, since the overlapping region of the grip portion includes the thin-walled portion, the vibration is damped faster, and the rider feels that the feeling of pushing up is reduced.

[Steering feeling]
Since the weight at a position far from the center of gravity of the vehicle is small, the moment of inertia is reduced, and it becomes difficult to feel the weight when tilting the vehicle or maintaining the posture. Therefore, the steering feeling is improved by thinning the overlapping region of the grip portions located at both ends of the steering wheel.

As described above, according to the embodiment of the present invention, the weight can be reduced without sacrificing the feeling of operation, so that the weight of the steering wheel can be reduced at the same time as the rider's fatigue is reduced.

Hereinafter, preferred configurations and modification examples of the handle 20 in the present embodiment will be described.

The wall thickness t2 of the thin portion p2 is preferably smaller than the wall thickness t0 of the mounting portion AP. When the wall thickness t2 of the thin portion p2 is smaller than the wall thickness t0 of the mounting portion AP, further weight reduction can be realized.

Further, as can be seen from the above, it is considered that the balance between the rigidity of the handle pipe 22 and the weight of the end portion affects the operability. By setting the ratio of the weights of the superimposed regions GP1a and GP2a to the weight of the entire handle pipe 22 within a predetermined range, a suitable operation feeling can be obtained more reliably. According to the study of the inventor of the present application, the thin portion p2 of the first superposed region GP1a and the second superposed region GP2a is the first superposed region GP1a and the second.
It was found that it is preferable that the weight (mass) of the superimposed region GP2a is formed so as to be 12% or less of the weight (mass) of the entire handle pipe 22. Table 3 below shows the results of verifying the relationship between the ratio of the weight of the superposed area to the weight of the handle pipe and the feeling of operation. Table 3 shows the ratio (weight ratio) of the weight of the superposed region to the weight of the handle pipe and the evaluation result of the operation feeling for each of the verified examples (Examples and Comparative Examples 1 to 9). As for the evaluation result of the operation feeling, suitable ones are shown as "○" and unsuitable ones are shown as "x". Table 3 also shows the weight of the superposed region, the weight of the entire handle pipe, and the wall thickness of the mounting portion and the grip portion (superimposed region and non-superimposed region) for each example.

From the comparison between Examples in Table 3 and Comparative Examples 2 to 5, it can be seen that a suitable operation feeling can be obtained when the ratio of the weight of the superposed region to the weight of the entire handle pipe is 12% or less. In Comparative Examples 6 to 9, although the ratio of the weight of the superposed region to the weight of the entire handle pipe was 12% or less, a suitable operation feeling could not be obtained. This is because the grip portion does not have a thick portion having a wall thickness greater than or equal to the thickness of the mounting portion (Comparative Examples 7 to 9), and has a thin portion having a wall thickness smaller than that of the thick portion. It is considered that this is due to the fact that it has not been done (Comparative Example 6).

As shown in FIGS. 5A and 5B, the thin portion p2 may be formed over substantially the entire first superimposing region GP1a and the second superimposing region GP2a. When the thin portion p2 is formed over substantially the entire overlapping regions GP1a and GP2a, it is easier to obtain a sufficient weight reduction effect. The boundary portion (step portion) between the thick portion p1 and the thin portion p2 may have an R-shaped corner (the cross section has an arc shape), or as illustrated in FIGS. 5 (a) and 5 (b). It does not have to be rounded in the corner.

Note that FIGS. 5A and 5B exemplify a configuration in which the wall thickness in the thin portion p2 is substantially the same along the longitudinal direction of the handle pipe 22 and is symmetric (symmetric with respect to the central axis). , Is not limited to such a configuration. As shown in FIGS. 6A and 6B, the wall thickness in the thin wall portion p2 may change along the longitudinal direction of the handle pipe 22. In the examples shown in FIGS. 6A and 6B, the wall thickness of the thin portion p2 decreases from the inside (adjacent bending portion side) to the outside.

Further, as shown in FIGS. 7A and 7B, each of the first superimposing region GP1a and the second superimposing region GP2a has a portion having a thickness other than the thin portion p2 (for example, the same thickness as the thick portion p1). The portion having) may be included. In the configuration exemplified in FIG. 7A, the thin portion p2 of the first overlapping region GP1a is at a predetermined position (first position) from the end of the first grip portion GP1 (the end opposite to the first bending portion BP1). ) It is formed up to l1. Further, in the configuration exemplified in FIG. 7 (b), the thin portion p2 of the second superposed region GP2a is located at a predetermined position (the end opposite to the second bent portion BP2) of the second grip portion GP2. 2 positions) It is formed up to l2. From the viewpoint of obtaining a sufficient weight reduction effect, it is preferable that the thin portion p2 is formed as wide (large) as possible in each of the first superposed region GP1 and the second superposed region GP2. Here, the boundary bd1 between the first superimposed region GP1a and the first non-superimposed region GP1b in the first grip portion GP1 is referred to as the first boundary, and the second superimposed region GP2a and the second non-superimposed region GP2b in the second grip portion GP2 are referred to. The boundary bd2 with and is called the second boundary. From the viewpoint of weight reduction, it is preferable that the distance d1 between the first position l1 and the first boundary bd1 and the distance d2 between the second position l2 and the second boundary bd2 are 30 mm or less, respectively.

Further, as shown in FIGS. 8A and 8B, the thin portion p2 may be formed so as to protrude from the non-superimposed regions GP1b and GP2b. In the configuration exemplified in FIG. 8A, the thin-walled portion p2 is located at a predetermined position (first position) in the first non-superimposed region GP1b from the end of the first grip portion GP1 (the end opposite to the first bent portion BP1). 3 positions) It is formed up to l3. Further, in the configuration exemplified in FIG. 8B, the thin-walled portion p2 is located at a predetermined position in the second non-overlapping region GP2b from the end of the second grip portion GP2 (the end opposite to the second bent portion BP2). (4th position) It is formed up to l4. From the viewpoint of rigidity, it is preferable that the distance d3 between the third position l1 and the first boundary bd1 and the distance d4 between the fourth position l4 and the second boundary bd2 are 30 mm or less, respectively.

Further, as shown in FIGS. 9A and 9B, the wall thickness of the grip portions GP1 and GP2 does not have to be the smallest at the outer end (the end not connected to the bending portion). In the configuration exemplified in FIG. 9A, the first superimposed region GP1a has a portion p3 at the outer end, which is not a thin portion p2 (that is, the wall thickness is not smaller than the thick portion p1). The outer diameter of this portion p3 is smaller than the outer diameter of the thin-walled portion p2. Further, in the configuration exemplified in FIG. 9B, the second superimposed region GP2a has a portion p3 at the outer end, which is not a thin portion p2 (that is, the wall thickness is not smaller than the thick portion p1). The outer diameter of this portion p3 is smaller than the outer diameter of the thin-walled portion p2. As described above, the first superimposed region GP1a and the second superimposed region GP2a may each include a thin portion p2 at least in a part thereof.

10 (a), (b) and (c) show examples of the shapes of the superimposed regions GP1a and GP2a in the cross section orthogonal to the longitudinal direction of the handle pipe 22. In FIGS. 10A, 10B, and 10C, the thick portion p1 of the non-superimposed regions GP1b and GP2b is shown by a dotted line.

In the example shown in FIG. 10A, the wall thickness in the thin wall portion p2 is smaller than the wall thickness in the thick wall portion p1 over the entire circumferential direction. As described above, when the wall thickness is thinned in the entire circumferential direction, the weight reduction effect is higher than that in the configuration in which the wall thickness is partially thinned in the circumferential direction.

In the examples shown in FIGS. 10 (b) and 10 (c), the wall thickness in the thin wall portion p2 is partially smaller than the wall thickness in the thick wall portion p1 in the circumferential direction. In the example shown in FIG. 10B, regions having a small wall thickness and regions having a large wall thickness (regions having the same wall thickness as the thick portion p1) are alternately arranged along the circumferential direction. In the example shown in FIG. 10 (c), the wall thickness continuously decreases and increases along the circumferential direction, and the contour of the inner peripheral surface is shaped like a spline curve. As described above, the configuration in which the wall thickness is partially thinned in the circumferential direction has an advantage that the bending rigidity of the first grip portion GP1 and the second grip portion GP2 can be easily adjusted.

Conventionally, it is known that a weight for reducing vibration is attached to the inside of the grip portion of the handle of the motorcycle, but the handle 20 in the present embodiment is inside the first grip portion GP1 and the second grip portion GP2. It is not necessary to have a weight attached to be located at.

As a material for forming the handle pipe 22, a non-ferrous metal material such as an aluminum alloy or a magnesium alloy can be preferably used. The embodiment of the present invention has great significance when the handle pipe 22 is formed of a non-ferrous metal material. When the handle pipe 22 is formed from an iron-based material such as steel, it is difficult to reduce the weight by reducing the wall thickness because the wall thickness is small, and when a composite material is used, it becomes very expensive and can be manufactured. This is because the energy required is also large. On the other hand, when the handle pipe 22 is made of a non-ferrous metal material, the wall thickness tends to increase as a whole when trying to secure the required rigidity under the restriction of the shape due to the riding posture of the rider. According to the embodiment of the present invention, by making good use of the relatively thick wall thickness (selectively forming the thin wall portion p2 as described above), the required rigidity is satisfied while the rider's fatigue is reduced. Can be planned.

Subsequently, a method of manufacturing the handle pipe 22 in the present embodiment will be described with reference to FIG. 11. FIG. 11 is a flowchart showing an example of a method for manufacturing the handle pipe 22.

First, a tubular workpiece is prepared (step S1). Here, a workpiece made of an aluminum alloy is prepared. For example, a workpiece (hydrostatic pressure extruded material) produced by a hydrostatic extrusion method is prepared, and then a workpiece is prepared by drawing. The hydrostatic pressure extrusion method is a kind of extrusion molding, and is a method of extruding a billet through a liquid (fluid) having an appropriate viscosity, instead of extruding the billet directly. As the workpiece, an extruded material other than the hydrostatic extruded material (for example, one produced by direct extrusion or indirect extrusion) or a drawn material may be used. The drawn material has excellent dimensional accuracy. Further, by using the extruded material, a workpiece having a uniform wall thickness can be obtained. By using the hydrostatic pressure extrusion method described above, it is possible to obtain a workpiece having higher strength than a general extruded material. Further, since the workpiece with higher dimensional accuracy can be obtained by performing the drawing process, the change in the moment of inertia of area is small and the uniformity of deformation is further improved. The workpiece prepared here (after drawing) has a constant outer diameter and inner diameter (that is, a constant wall thickness) over the entire workpiece. As the aluminum alloy, for example, an Al-Mg-Zu-Cu based aluminum alloy can be preferably used.

Next, processing (diameter reduction processing) is performed to make the outer diameter of the region to be the first grip portion GP1 and the second grip portion GP2 of the workpiece smaller than the outer diameter of the region to be the mounting portion AP. Here, swaging processing (also referred to as “rotary cold forging processing”) is performed (step S2). The diameter reduction processing (drawing processing) may be a method other than the swaging processing (for example, spinning processing).

After that, the workpiece is processed to thin a part of the region to be the first grip portion GP1 and the second grip portion GP2 (step S3). This thinning step can be suitably performed by, for example, machining (for example, cutting).

Subsequently, a solution treatment is performed on the workpiece (step S4). The temperature and time of the solution treatment are set according to the composition of the aluminum alloy. The solution treatment is performed, for example, at 470 to 480 ° C. for 1 to 3 hours.

Then, the workpiece is bent (step S5). By this bending process, the first bent portion BP1 and the second bent portion BP2 are formed.

Next, the workpiece is subjected to artificial aging treatment (step S6). The artificial aging treatment is performed, for example, at 115 to 125 ° C. for 3 to 6 hours and then at 170 to 180 ° C. for 6 to 12 hours. The solution heat treatment and the artificial aging treatment may be collectively referred to as T7 heat treatment. In this embodiment, bending is performed between the solution treatment and the artificial aging treatment in the T7 heat treatment.

Next, a shot peening process is performed on the workpiece (step S7). The shot peening process is performed to improve the fatigue strength.

After that, the workpiece is anodized (step S8). The alumite treatment is a step of forming an anodizing film on the surface of the aluminum alloy.

In this way, the handle pipe 22 can be obtained. According to the manufacturing method of the present embodiment, the effect that the flatness of the first bent portion BP1 and the second bent portion BP2 of the handle pipe 22 can be reduced can be obtained. The reason for this will be described below.

FIG. 12 is a flowchart showing a method of manufacturing a handle pipe according to a reference example. In the manufacturing method of the reference example, first, an extruded material is prepared as a workpiece (step S11), and then drawing processing is performed (step S12).

Subsequently, the workpiece is subjected to a swaging process (step S13), and then an annealing process for softening the workpiece (step S14).

Next, a bending process is performed (step S15), and then a solution treatment process is performed (step S16). After that, a correction process is performed (step S17).

Subsequently, artificial aging treatment (step S18), shot peening treatment (step S19), and alumite treatment (step S20) are sequentially performed.

In the manufacturing method of the reference example, since the solution treatment (step S16) is performed after the bending process (step S15), high temperature holding and quenching are performed after molding into the product shape, and the deformation due to the heat treatment becomes large. Therefore, it is necessary to perform a straightening treatment (step S17) after the solution treatment.

On the other hand, in the manufacturing method of the present embodiment, the solution treatment (step S4) is performed before the bending process (step S5), so that the straightening treatment is unnecessary. Further, since the bending process is performed after the workpiece is hardened to some extent by the solution heat treatment, the cross-sectional shape of the first bent portion BP1 and the second bent portion BP2 is less likely to change. Therefore, the flatness of the first bent portion BP1 and the second bent portion BP2 can be reduced. Here, the flatness is defined as (maximum diameter-minimum diameter) / 100 / average diameter. When the flattening ratio is large, the difference in rigidity depending on the load direction increases. Therefore, from the viewpoint of the uniformity of rigidity, the flatness of the first bent portion BP1 and the second bent portion BP2 is preferably small, and specifically, the first bent portion BP1 and the second bent portion BP2, respectively. The flatness in the central portion of the above is preferably 5% or less. Further, since the manufacturing method of the present embodiment does not require annealing treatment, it is possible to reduce the time and energy required for manufacturing.

It should be noted that the bending process can be performed without any problem even after the solution treatment, because the workpiece can have sufficient plastic deformability even if it becomes hard to some extent by the solution treatment. FIG. 13 shows examples of stress-strain curves after annealing and solution treatment for workpieces made of aluminum alloy. From FIG. 13, it can be seen that even after the solution treatment, the yield ratio obtained by dividing the yield point by the tensile strength is small, and the yield point has sufficient plastic deformability.

As in the method illustrated in FIG. 11, the prepared workpiece is preferably one produced by the hydrostatic pressure extrusion method (hydrostatic pressure extrusion material). This is because the hydrostatic pressure extruded material is superior in strength to a general extruded material, so that the thickness can be made thinner and the weight can be further reduced.

In the example shown in FIG. 11, the thinning process is performed between the swaging process and the solution processing, but the timing of the thinning process is not limited to this example. The thinning process may be performed between the artificial aging treatment and the shot peening treatment, between the shot peening treatment and the alumite treatment, or may be performed after the alumite treatment.

Further, during the swaging process, the wall thickness of the regions that become the superimposed regions GP1a and GP2a may be smaller than the wall thickness of the regions that become the non-superimposed regions GP1b and GP2b. That is, the thinning process may be performed at the same time as the swaging process. For example, a stepped core metal including a portion having a relatively large outer diameter (large diameter portion) and a portion having a relatively small outer diameter (small diameter portion) is prepared, and a portion serving as a grip portion GP1 and GP2 of the workpiece. By performing a swaging process so that the inner peripheral surface of the stepped core is in contact with the stepped core metal, a thick portion p1 is formed corresponding to the small diameter portion, and a thin portion p2 is formed corresponding to the large diameter portion. be able to.

The embodiment of the present invention can be suitably used for a configuration in which the outer diameter of the attachment portion AP of the handle pipe 22 is larger than the outer diameter of the grip portions GP1 and GP2 (so-called “taper handle”). When a handle pipe for a tapered handle is manufactured by, for example, swaging, the wall thickness increases from the center portion (mounting portion) of the handle pipe toward the end portion side. Therefore, the weight of the handle pipe is likely to increase. As in the embodiment of the present invention, the first grip portion GP1 and the second grip portion GP2 of the handle pipe 22 include the thin-walled portion p2, so that the weight reduction in the tapered handle can be suitably realized.

The embodiment of the present invention is not limited to the tapered handle. That is, the embodiment of the present invention can also be used in a configuration in which the outer diameters of the grip portions GP1 and BP2 are the same as the outer diameter of the mounting portion AP.

Further, in the description so far, the motorcycle is exemplified as the saddle-mounted vehicle, but the saddle-mounted vehicle is not limited to this. The handle according to the embodiment of the present invention is suitably used for various saddle-type vehicles such as bicycles, snowmobiles, ATVs (All Terrain Vehicles), and personal watercrafts. In this case, the steering wheel according to the embodiment of the present invention can be suitably used for the steering device capable of changing the traveling direction of various saddle-mounted vehicles.

As described above, in the saddle-mounted vehicle handle 20 of the embodiment of the present invention, each of the first grip portion GP1 and the second grip portion GP2 of the handle pipe 22 has a wall thickness of t0 or more of the mounting portion AP. It includes a thick portion p1 having t1 and a thin portion p2 having a wall thickness t2 smaller than the wall thickness of the thick portion p1. Specifically, the thick portion p1 is a first non-superimposition region (a region that does not overlap with the first handle grip 21A) GP1b of the first grip portion GP1 and a second non-superimposition region (second handle) of the second grip portion GP2. (Area that does not overlap with the grip 21B) It is formed in GP2b, and the thin-walled portion p2 is specifically the first grip portion GP.
1 is formed in the first superimposing region (region overlapping with the first handle grip 21A) GP1a and the second superimposing region (region overlapping with the second handle grip 21B) GP2a of the second grip portion GP2. Since the first grip portion GP1 and the second grip portion GP2 include the thick portion p1, a sufficient sense of rigidity can be ensured. Further, since the first grip portion GP1 and the second grip portion GP2 include the thin-walled portion p2, the weight is lighter than, for example, when the entire first grip portion GP1 and the second grip portion GP2 are the thick-walled portion p1. Can be achieved. Further, the thick portion p1 is arranged in the regions (first non-superimposition region GP1b and second non-superimposition region GP2b) located relatively inside the first grip portion GP1 and the second grip portion GP2, and relatively outside. By arranging the thin-walled portion p2 in the region located in (the first superimposing region GP1a and the second superimposing region GP2a), the feeling of pushing up can be reduced. Therefore, the rider's fatigue can be suppressed. As described above, according to the embodiment of the present invention, the weight of the handlebar 20 for a saddle-mounted vehicle can be reduced while reducing the fatigue of the rider.

When the wall thickness t2 of the thin portion p2 is smaller than the wall thickness t0 of the mounting portion AP, further weight reduction can be realized.

From the viewpoint of more reliably obtaining a sufficient weight reduction effect and a reduction in the feeling of pushing up, the thin-walled portion p2 is a respective of the first superposed region GP1a of the first grip portion GP1 and the second superposed region GP2a of the second grip portion GP2. It is preferable that the mass is formed so as to be 12% or less of the mass of the entire handle pipe 22.

Further, from the viewpoint of weight reduction, it is preferable that the thin portion p2 is formed as wide (large) as possible in each of the first superposed region GP1a and the second superposed region GP2a. For example, the thin portion p2 of the first superposed region GP1a may be formed from the end of the first grip portion GP1 (the end opposite to the first bent portion BP1) to a predetermined position (first position) l1. The thin portion p2 of the second superposed region GP2a may be formed from the end of the second grip portion GP2 (the end opposite to the second bent portion BP2) to a predetermined position (second position) l2. .. The boundary bd1 between the first superposed region GP1a and the first non-superimposed region GP1b in the first grip portion GP1 is called the first boundary, and the boundary between the second superposed region GP2a and the second non-superimposed region GP2b in the second grip portion GP2. When bd2 is referred to as a second boundary, the distance d1 between the first position l1 and the first boundary bd1 and the distance d2 between the second position l2 and the second boundary bd2 are preferably 30 mm or less, respectively.

When the thin portion p2 is formed over substantially the entire of each of the first superposed region GP1a and the second superposed region GP2a, it is easier to obtain a sufficient weight reduction effect.

When the wall thickness in the thin wall portion p2 is smaller than the wall thickness of the thick wall portion p1 over the entire circumferential direction (that is, the wall thickness is thinned in the entire circumferential direction), the wall thickness is partially thinned in the circumferential direction. Compared to the existing configuration, the weight reduction effect is high.

When the wall thickness of the thin wall portion p2 is partially smaller than the wall thickness of the thick wall portion p1 in the circumferential direction, it is easy to adjust the bending rigidity of the first grip portion GP1 and the second grip portion GP2.

The wall thickness in the thin portion p2 may be substantially the same along the longitudinal direction of the handle pipe 22 and may be symmetric, or may vary along the longitudinal direction of the handle pipe 22.

The handle 20 for a saddle-mounted vehicle according to the embodiment of the present invention does not have to include a weight attached so as to be located in the first grip portion GP1 and the second grip portion GP2.

The embodiment of the present invention has great significance when the handle pipe 22 is formed of a non-ferrous metal material. This is because when the handle pipe 22 is formed from an iron-based material such as steel, the wall thickness is small, and it is difficult to reduce the weight by reducing the wall thickness. On the other hand, when the handle pipe 22 is made of a non-ferrous metal material, the wall thickness tends to increase as a whole when trying to secure the required rigidity under the restriction of the shape due to the riding posture of the rider. According to the embodiment of the present invention, by making good use of the relatively thick wall thickness (selectively forming the thin wall portion as described above), the required rigidity is satisfied and the rider's fatigue is reduced. Can be planned.

The embodiment of the present invention is suitable for a configuration in which the outer diameter od1 of the attachment portion AP of the handle pipe 22 is larger than the outer diameter od2 of each of the first grip portion GP1 and the second grip portion GP2 (so-called "taper handle"). Can be used for. When a handle pipe for a tapered handle is manufactured by, for example, swaging, the wall thickness increases from the center portion (mounting portion) of the handle pipe toward the end portion side. Therefore, the weight of the handle pipe is likely to increase. As in the present invention, when the first grip portion GP1 and the second grip portion GP2 of the handle pipe 22 include the thin-walled portion p2, weight reduction in the tapered handle can be suitably realized.

From the viewpoint of uniformity of rigidity, it is preferable that the flatness of the first bent portion BP1 and the second bent portion BP2 is small, and specifically, the flatness in the central portion of the first bent portion BP1 and the second bent portion BP2. The rate is preferably 5% or less.

In the production method according to the embodiment of the present invention, the solution treatment is performed before the bending process. When the solution treatment is performed after the bending process, high temperature holding and quenching are performed after molding into the product shape, so that the deformation due to the heat treatment becomes large. Therefore, it is necessary to perform a straightening treatment after the solution treatment. On the other hand, in the production method of the present invention, the solution treatment is performed before the bending process, so that the straightening treatment becomes unnecessary. Further, since the bending process is performed after the workpiece is hardened to some extent by the solution heat treatment, the cross-sectional shape of the first bent portion BP1 and the second bent portion BP2 is less likely to change. Therefore, the flatness of the first bent portion BP1 and the second bent portion BP2 can be reduced.

The prepared workpiece is preferably one produced by an extrusion method (extruded material), and more preferably one produced by a hydrostatic pressure extrusion method (hydrostatic pressure extruded material). The extruded material has excellent wall thickness uniformity. The hydrostatic pressure extruded material is superior in strength to a general extruded material.

A part of the region to be the first grip portion GP1 and the second grip portion GP2 may be thinned. Each of the first grip portion GP1 and the second grip portion GP2 has a thick portion p1 having a wall thickness t1 equal to or larger than the wall thickness t0 of the mounting portion AP, and a wall thickness t2 smaller than the wall thickness t1 of the thick portion p1. By including the thin-walled portion p2, the weight can be reduced and the rider's fatigue can be suppressed.

The step of thinning a part of the region to be the first grip portion GP1 and the second grip portion GP2 can be preferably performed by, for example, machining.

Further, in the manufacturing method according to the embodiment of the present invention, the outer diameter of the region to be the first grip portion GP1 and the second grip portion GP2 of the workpiece is reduced to be smaller than the outer diameter of the region to be the mounting portion AP. Includes process (diameter reduction process). This diameter reduction step can be preferably performed by, for example, swaging. In that case, in the diameter reduction step, a part of the region to be the first grip portion GP1 and the second grip portion GP2 can be thinned.

According to the embodiment of the present invention, the weight of the steering wheel for a saddle-mounted vehicle can be reduced while reducing the fatigue of the rider. The handle for a saddle-type vehicle according to the embodiment of the present invention is suitably used for various saddle-type vehicles.

1 Motorcycle (saddle-mounted vehicle)
2 Body frame 3 Engine 4 Front wheels 5 Rear wheels 6 Seat seats 7 Fuel tank 8 Upper bracket 9 Under bracket 10a 1st main frame 10b 2nd main frame 11 Down frame 12a 1st lower frame 12b 2nd lower frame 13 Head pipe 14a, 14b Rear arm 15a 1st rear frame 15b 2nd rear frame 16 Pivot shaft 17 Front fork 20 Handle 21A 1st handle grip 21Af 1st handle grip flange 21B 2nd handle grip 21Bf 2nd handle grip flange 22 Handle pipe 30 Steering device 31 Steering rotation device AP mounting part BP1 1st bending part BP2 2nd bending part GP1 1st grip part GP1a 1st superimposing area GP1b 1st non-superimposing area GP2 2nd grip part GP2a 2nd superimposing area GP2b 2nd non-superimposing Area p1 Thick part p2 Thin part

Claims (5)

A mounting part located in the center of the longitudinal direction and attached to the steering rotating device,
The first grip located at one end in the longitudinal direction,
The second grip located at the other end in the longitudinal direction,
A first bent portion located between the mounting portion and the first grip portion and extending from one end of the mounting portion to one end of the first grip portion in a direction different from that of the mounting portion.
A second bent portion located between the mounting portion and the second grip portion and extending from the other end of the mounting portion to one end of the second grip portion in a direction different from the mounting portion.
It is a manufacturing method of a handle pipe for a saddle-type vehicle having
Step (A) of preparing a tubular workpiece made of a metal material, and
The step (B) of performing processing to make the outer diameter of the region to be the first grip portion and the second grip portion of the workpiece smaller than the outer diameter of the region to be the mounting portion.
After the step (B), a step (C) of performing a solution treatment on the workpiece and a step (C).
A method for manufacturing a handle pipe for a saddle-mounted vehicle, comprising the step (D) of bending the workpiece after the step (C). The method for manufacturing a handle pipe for a saddle-mounted vehicle according to claim 1, wherein the workpiece prepared in the step (A) is a workpiece manufactured by an extrusion method. Further including the step (E) of thinning a part of the region to be the first grip portion and the second grip portion,
Each of the first grip portion and the second grip portion has a thick portion having a wall thickness equal to or larger than the wall thickness of the mounting portion and a thin portion having a wall thickness smaller than the wall thickness of the thick portion. The method for manufacturing a handle pipe for a saddle-type vehicle according to claim 1 or 2, which includes the method. The method for manufacturing a handle pipe for a saddle-type vehicle according to claim 3, wherein the step (E) is performed by machining after the step (B). The step (B) is performed by swaging.
The method for manufacturing a handle pipe for a saddle-mounted vehicle according to claim 3, wherein in the step (B), the step (E) is also performed.

Images