JPS58191953A - Measuring device of ground pressure distribution of tyre - Google Patents

Abstract

PURPOSE:To detect automatically ground pressures of a front wheel and a rear wheel and to measure accurately the ground pressure distribution in the whole of the ground contacting face of a tyre, by moving a pressure sensing plane plate, which is pressed by the ground contacting face of the tyre to detect the ground pressure, in the direction, where this plane plate is deviated from the running position of the tyre, when the tyre gets over the plane plate. CONSTITUTION:When the tyre is run from one slope 4 in the direction of an arrow P in a figure, the front wheel passes on one pressure sensing paper 9a, which is arranged on a pressure sensing plane plate 3, with a prescribed ground pressure, and the ground pressure distribution chart of the front wheel is left on the pressure sensing paper 9a. When the front wheel passes through a trigger bar 6, the front wheel presses downward the rear frame material of the trigger bar 6, and therefore, a pawl 6a of the trigger bar 6 is pulled upward with a pivotal fulcrum 10 as the center, and the trigger bar 6 is disengaged from the pressure sensing plane plate 3, and the plane plate 3 is moved for a distance longer than the width of the tyre in the direction orthogonal to the running direction of the tyre by a spring 7, and as the result, a pressure sensing paper 9b is placed in the running position of the tyre. Thereafter, the rear wheel passes on the other pressure sensing paper 9b on the pressure sensing plane plate 3, and the ground pressure distribution chart of the rear wheel is left on the pressure sensing paper 9b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for measuring the distribution of ground pressure in various parts of a tire's contact surface.

Conventionally, as shown in Figure 1, there is a conventional method for measuring the ground pressure of a tire. C
) is pressed, and the pressing force detected by the load detector (b) is divided by the contact area of the tire to calculate the ground contact pressure. However, with this method, if the grooves or sipes of the tread of the tire (C) are located in the contact area of the load sensor (4), the actual contact area cannot be determined, so the ground contact pressure cannot be accurately measured.

Furthermore, this type of measurement can only measure the average pressure of only a portion of the tire's contact surface, and in order to measure the pressure distribution state of the entire ground pressure, it is necessary to bury a large number of load detectors (b). This significantly complicates the workability of assembling the device, measuring, etc., and also requires time and effort to measure the front wheels and rear wheels individually when #j is determined using an actual vehicle.

An object of the present invention is to provide a tire ground pressure distribution measuring device that can accurately measure the ground pressure distribution over the entire ground surface and can solve the above-mentioned problem.

The ground pressure distribution map of the present invention is hereinafter referred to as the “equipment” (hereinafter referred to as the device).
(1) will be explained based on the drawings. FIG. 2 is a perspective view schematically showing the apparatus of the present invention. In the figure, the device (1) includes a slope (4) (4), which becomes the tire running surface, and a support plate (
2) and a support body (toward) comprising a trigger extension stand (5); and a pressure-sensitive flat plate (3) made of a synthetic resin plate placed on the support plate (2) in the tire running direction; Pressure sensitive plate (3
) consists of a trigger rod (6) for moving the pressure-sensitive plate (3) after the tire has run over it. The trigger rod (6) has a U-shape, and has a side frame member pivotally supported by a trigger extension table (5), and claws (6a) are provided at both ends of the side frame member.
631) is a retaining hole (631) drilled in the side of the pressure-sensitive plate (3).
8) prevents the pressure sensitive plate (3) from moving due to the extended spring (7). Also feeling 9a
) (9b) are pasted apart from each other by the moving distance.

However, when measuring the ground pressure distribution of a tire using the lever device (1), when the tire is run from direction P in the figure through one slope (4), the front wheel is placed on the pressure-sensitive plate (3). The ground pressure distribution map of the front wheel is left on the pressure sensitive paper (9a''l-h) at a predetermined ground pressure.Also, when the front wheel passes the trigger rod (6), In order to push down the rear material of the trigger rod (6), the pivot point (
The pawl (6a) of the trigger rod (6) is pulled upwards centering on the pressure-sensitive plate (3), and
As a result of the spring (7) moving a distance exceeding the width of the tire in a direction perpendicular to the tire running direction, the other pressure-sensitive paper (9b) on the pressure-sensitive flat plate (3) moves to the tire running position. It will be located in After that, the rear wheel moves from the slope (4) to the other pressure sensitive paper (9b) on the pressure sensitive plate (3).
), and the pressure-sensitive paper (9b) K leaves a 45-minute diagram of the rear wheel's contact with the ground.

Note that the pressure-sensitive paper (9a) (9) is used to measure the ground pressure distribution.
b) #i, one that shows shading depending on the magnitude of the ground pressure, or one that has been commonly used, such as a book that changes color, can be adopted. In addition, in this embodiment, in order to improve the sensitivity of the ground pressure distribution on the pressure-sensitive paper (9a) (9b), an elastic sheet with projections υ regularly arranged on one side is placed on the pressure-sensitive paper (9a) (9b). The α force is arranged so that the protrusion 02 faces the pressure sensitive paper (9a) (9b). Here, the protrusion (c) is preferably a hemispherical one, but any other type can be used as long as it helps improve sensitivity and reproducibility. It is desirable to consist of the body.

As mentioned above, the device of the present invention is capable of automatically and accurately measuring the ground pressure of each front and rear tire at the same time.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional ground pressure measuring method, FIG. 2 is a schematic diagram of a measuring device of the present invention, and FIG. 3 is a partial front view of an elastic sheet. (3)...-Pressure-sensitive flat plate, (9a), (9b)...Pressure-sensitive paper 0 force...Elastic sheet. Patent applicant: Sumitomo Rubber Industries, Ltd.

Claims (1)

[Scope of Claims] (1) When the tire crosses over, a pressure-sensitive flat plate is pressed on the tire contact surface and is used to detect the ground pressure. The device according to claim 1, wherein pressure-sensitive paper is placed on a flat clapperboard. (3) Pressure-sensitive paper is placed on a pressure-sensitive flat plate 1, and an elastic sheet having protrusions regularly arranged on one side thereof is placed on top of the pressure-sensitive paper so that the protrusions face the pressure-sensitive paper. The device according to paragraph 1. (4) Claim 8, in which the protrusion is a rubber elastic protrusion
Apparatus described in section. (5) The device according to claim 3, wherein the protrusion has a hemispherical shape.