JPS62282239A - Method and apparatus for endurance test of motorcycle - Google Patents

Abstract

PURPOSE:To shorten an endurance testing time, by a method wherein the front wheel of a motorcycle is mounted on a front wheel supporting means forwardly declined at the angle corresponding to the stress applied to a steering stem and the load corresponding to the load at the time of jumping is repeatedly imposed on the center-of-gravity part of the motorcycle. CONSTITUTION:A motorcycle 1 having front and rear wheels 3, 4 mounted thereto is placed on the front and rear wheel supporting stands 11, 14 of a tester through dummy cushions 9, 9 and a brake panel 8 is supported by an arm lever 25. The piston levers 16, 20 arranged between the supporting stands 11, 14 so as to repeatedly apply load to a car body are fixed to a dummy engine 5 and a step 7. In this state, downward loads W1, W2 corresponding to load are repeatedly applied to the motorcycle 1 on the basis of an actually measured load value applied to the motorcycle 1 at the time of jumping. Therefore, the stress acting on the motorcycle at each time of jumping can be faithfully reproduced in a testing chamber and a required repeated test can be performed within a short time.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Field of Industrial Application) The present invention particularly relates to a method and apparatus for testing the durability of motocross.

(Prior Art) Motorcycles for riding on rough roads are particularly required to have strong and durable body and suspension parts. For this reason, in addition to the normal durability tests at the prototype stage, this type of bike must be subjected to long-term driving tests on rough roads by experienced riders, or as described in Japanese Utility Model Publication No. 84561/1983. The bike is repeatedly tested by placing the bike on top of a roller with such unevenness.

However, in the former test method, individual differences between riders will occur, and for example, if an actual riding test is conducted with the endurance mileage of this type of bike set to 2000 km and the number of jumps set to 10 times per I km, However, it took almost a month to complete the test, which was a negative burden in terms of labor, time, and economy.

There is a problem that the load on the load becomes significantly large, and the latter test method is only a test of running on rough roads, and cannot reproduce the impact caused by jumping, and although it is good for testing the suspension, The problem is that it is not suitable for investigating wIP8.

(Purpose) The present invention was made in view of the above problem, and its purpose is to faithfully reproduce the impact that a motorcycle receives during a jump, and to conduct the necessary repeated tests in a short period of time. The purpose of the present invention is to provide a new durability test method for motocross bikes that can be carried out in the future, and an apparatus therefor.

(Means for Accomplishing the Object) That is, in order to achieve the object, the present invention provides a means for placing a front wheel holder in front of a test bike at an angle corresponding to the stress applied to the steering stem. To provide a motorcycle durability test method and device in which a downward force corresponding to the load is repeatedly applied to the center of gravity of the motorcycle based on the measured value of the load applied to the motorcycle during a jump in this state.

(Example) The details of the present invention will be explained below based on an example.When a motorcycle that generally travels at high speed on rough roads rides on a convexity formed on the ground, the motorcycle 1 becomes as shown in FIG. like,
Draw a flight line determined by the speed and the inclination angle e of the convex part, and then use the flying blade shoe, the height h of the convex part, the inclination angle θ, and the bike 1.
After flying a distance HD corresponding to the speed of , it lands with its rear wheels first.

For this reason, every time the bike 1 jumps, an impact load proportional to the vehicle weight including the rider, the height h of the convex part, and the flying distance HD is applied, and also due to the front wheel landing later. , the steering stem 2 (Fig. 1) has casters (
A moment M is applied which is determined by the front wheel's angle of inclination) and the impact load.

The present invention tests the durability of each part of the bike 1 by repeatedly subjecting it to a load equivalent to the actual load applied during a jump. This figure shows an example of a device that can be used.

A front wheel holder 1 for supporting the front wheel 3 of the test bike 1 is mounted on the board indicated by reference numeral 10 in the figure, and the lower end thereof is pivoted downwardly in front of the board 10 by means of a fulcrum pin 12. The upper end is adjustable (attached to the slide par 13) so that the inclination angle α can be changed so that the component force of the downward load by the first cylinder 15 becomes a load equivalent to the stress applied when the front wheel 3 lands on the ground. Further, behind it, a rear wheel cradle] 4 that supports the test bike 1 and the contact wheels 4 so as to be almost horizontal is disposed.

Reference numerals 15 and 19 denote two cylinders disposed between them, and a piston rod 16 protruding from the first cylinder 15 in front of the two cylinders is attached to the engine, which forms the center of gravity of the test bike 1, through a ball joint 17. This dummy engine 5 is combined with a plate-shaped dummy engine 5 attached to the
It is configured so that the load at the time of landing is applied to
As shown in FIG. 2, a bar-shaped mounting bracket 22 is attached to the 7s-not+'>n/7-t end via a ball joint 21, and rods provided at both ends of this mounting bracket 22 are attached to the end. 23.23 is connected to each step 7.7 fixed to the frame 6 via a ball joint 24.24, so that the same load upon landing is applied to the step 7.

In addition, the reference numeral 25 in the figure indicates an arm rod fixed to the lyceter brake panel 8 to suppress the back and forth movement of the test bike 1.

The front and rear wheel cradle of the device configured in this way] 1.14 is connected to the front and rear wheels 3 via a rigid dummy cushion 9.9.
．． 4 is mounted on the bike 1, the brake panel 8 is supported by the arm rod 25, and each cylinder 15 is disposed between the pedestal 11 and ]4 so as to apply repeated loads to the vehicle body.
．． 19 piston rod) 6.20% dummy engine 5 and fixed in step 7.7.

In this state, for example, let's say that the bike 1 flies at a speed of about 40 meters per hour over a bump with a height of 0.7 meters for a distance of 10 meters, and the stress applied to the step 7 and the cushion arm 6a at that time is actually measured. This is converted into a load, and based on this, the oil pressure to be supplied to the first cylinder 15 and the second cylinder ]9 is set to 428.6, 9, and 1, respectively.
A tensile force of 9 is applied to the first cylinder 15, and the stress applied to the steering stem 2 when the front @3 lands is actually measured and converted into a load, and the above-mentioned downward tensile force of the first cylinder 15 is calculated. Fix the front wheel cradle with an angle of inclination α such that the force is equal to the above load.

Then, increase the bike's service life to 2000 m.
, 1 is set as the number of jumps per m traveling, tlo times, and a total of 20,000 downward loads Wl and W2 are repeatedly applied to the dummy engine 5 and step 7. This results in
With the required time of 50 to 55 hours per 91 test bikes, the impact load applied to the frame 6 and the suspension area at the time of landing can be repeatedly applied, and at the same time, the steering stem 2 has a The stress applied when the front wheel subsequently lands on the ground can be applied repeatedly.

After completing this test, it is sufficient to carefully check each part of the frame and the undercarriage to see if there are any cracks or the like.

Although not shown in the diagram, this device has a built-in device for each part of the car body so that in the unlikely event that a part of the car body is damaged during the test, the test can be stopped at that point. A limit switch is installed to stop the device.

In addition, the above-mentioned test device has two cylinders]5.19
It is configured to distribute the load to the dummy engine 5 and the frame 6, but with a single cylinder, only the part of the frame 6 near the center of gravity of the car body receives the full British impact load when landing. It can also be configured to add

In general, the above-described durability test can be applied not only to two-wheeled bikes but also to three-wheeled bikes called three-wheelers, four-wheeled bikes called multi-wheeled bikes, and the like.

(Effects) As described above, according to the present invention, the front wheel holder, which has an angle corresponding to the stress applied to the steering stem, is mounted on the front wheel of the motorcycle as a means, and is placed at the center of gravity of the motorcycle when jumping. By repeatedly applying a load equivalent to the load of The development of new bikes, etc. can be greatly promoted without being able to do so.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a test device showing an embodiment of the present invention, FIG. 2 is a perspective view of the main parts of the same device, and FIG. 3 is an explanatory diagram showing a motorcycle in a jumping state. ]... Babaira... Steering stem

Claims (1)

[Claims] 1. The front wheel of a test bike is placed on a front-sloping front wheel receiving means with an angle corresponding to the stress applied to the steering stem, and based on the actual measured value of the load applied to the bike during a jump in this state. A motorcycle durability test method, characterized in that a downward force corresponding to the load is repeatedly applied to the center of gravity of the motorcycle. 2. A front wheel support means with a forward downward angle corresponding to the stress applied to the steering stem, a nearly horizontal rear wheel support means, and a load corresponding to the load applied to the bike during a jump at least on the test bike. A motorcycle durability test device comprising a load applying means that repeatedly applies a load to the center of gravity of the bicycle. 3. The motorcycle durability testing device according to claim 2, wherein a universal joint is interposed between the load applying means and the attachment portion to the center of gravity of the motorcycle.