JPH023136B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slip tester that measures the slip resistance coefficient between two objects to be measured when they come into contact with each other, and in particular measures the slip resistance coefficient in curved contact or point contact. This invention relates to a slip tester suitable for.

Conventionally, the slip resistance coefficient between a non-slip material for stairs and the bottom of a covering such as a shoe sole has been measured using a pendulum-type floor slip tester that measures the slip resistance coefficient of floor finishing materials. This was done based on the principle shown in the figure.

To explain this, 1 is a hammer, which is swingable about a point O as a fulcrum. The hammer 1
A shoe sole material 2 is attached to the lower end of the shoe so as to be movable in the direction of arrow A, and a spring 3 is interposed between the shoe sole material 2 and the lower end of the hammer 1.

First, the hammer 1 is lifted to a lifting position (indicated by the solid line) at a predetermined height B, and then the hammer 1 is released and the hammer 1 is swung as shown by the arrow C. The sole material 2 is made to come into sliding contact with the surface of the anti-slip material 4 for stairs fixed below the hammer 1 when the shoe sole material 2 becomes vertical as shown by the one-dot chain line position. Here, the slip resistance coefficient between the anti-slip material 4 and the sole material 2 is:
It can be determined by the height D of the swing-up position of the hammer 1, which is indicated by the two-dot chain line position.

However, in such a conventional test method, when the anti-slip material 4 for stairs and the shoe sole material 2 come into sliding contact,
The spring 3 vibrates, and the contact pressure between the anti-slip material 4 and the shoe sole material 2 fluctuates due to the vibration of the spring 3, resulting in a drawback that accurate measurement values cannot be obtained.

In addition, since the conventional measuring method is based on the assumption that walking is performed on a flat floor surface, the manner of contact of the shoe sole material 2 with the anti-slip material 4 is as shown in FIG. This corresponds to the case where the heel of the shoe 5 contacts the shoe 4.

However, slipping when walking on stairs occurs at the moment when the toe area of the sole comes into contact with the tip of the stair tread, as shown in FIG. 3, when descending the stairs. Therefore, the conventional measuring method has the disadvantage that only a slip resistance coefficient that does not correspond to the actual conditions can be obtained.

The present invention has been made in order to eliminate the above-mentioned conventional drawbacks, and it does not cause large errors in measurement values due to spring vibrations, etc., and also allows two objects to be measured to be contacted at any part and at any contact angle. An object of the present invention is to provide a slip tester that can measure the slip resistance coefficient when the contact is made, and is suitable for measuring the slip resistance coefficient in line contact or point contact.

The present invention will be explained below based on embodiments shown in the drawings.

4 to 9 show an embodiment in which the present invention is applied to a stair slip tester for measuring the slip resistance coefficient between a stair anti-slip material and a shoe sole.

The base 6 has three leg screws 7 screwed together in the vertical direction, and is placed on a suitable installation surface via the leg screws 7. Therefore, the level of the base 6 can be obtained by rotating the leg screws 7 and adjusting the amount of protrusion of the lower end of the leg screws 7 from the base 6.

A rotary table 9 is rotatably supported on the base 6 about a rotary table shaft 8 extending in the horizontal direction. Further, a support 10 is erected on the base 6,
A pulley 11 is rotatably supported at the upper end of this column 10. Further, a motor 12 is attached to the base 6, and the rotating shaft of the motor 12 is connected to the input shaft of a speed reducer (not shown) housed in a gearbox 13. A take-up pulley (not shown) is attached to the output shaft of the reduction gear, and one end of the thread 14 is wound around the take-up pulley. This thread 1
The other end of 4 is attached to the end of the rotating table 9 on the opposite side to the rotating table shaft 8. Further, the middle portion of the thread 14 is wound around the pulley 11.

Near the end of the rotating table 9 on the shaft 8 side, two supports 15 are erected to face each other.
A fan-shaped plate 17 is rotatably supported on each of these supports 15 via a shaft 16 extending parallel to the rotary table shaft 8, and a rotary member 18 having an L-shaped cross section is provided between each of the fan-shaped plates 17. is fixed.

Further, a scale 19 is attached to the arcuate peripheral edge of one of the sector plates 17. moreover,
One of the supports 15 is provided with a scale support portion 20 for indicating the scale 19.

A fixing screw 21 is horizontally screwed into the support 15, and the tip of the fixing screw 21 is connected to the fan-shaped plate 1.
7, the fan-shaped plate 17 and the rotating member 18 can be fixed at a desired rotating position. A sector-shaped scale plate 17 is attached to the base 6 with its center aligned with the rotary table shaft 8, and a scale 23 is provided on the arc-shaped peripheral edge of the scale plate 22. On the other hand, a scale support needle 24 for indicating the scale 23 is attached to the rotating table 9.

A support 40 is erected at the end of the rotation table 9 opposite to the rotation table shaft 8, and a horizontal portion 40a is integrally provided at the upper end of the support 40. Further, a rotating table shaft 8 is provided at the tip of the horizontal portion 40a.
A suspension shaft guide portion 40b is provided that extends perpendicularly thereto. A long hole 25 is provided in the guide portion 40b in a direction perpendicular to the rotary table shaft 8, and a suspension shaft 26 passes through the long hole 25. Two nuts 27 are screwed onto the suspension shaft 26 above and below the guide portion 40b.

The center portion of a suspension plate 28 is fixed to the lower end of the suspension shaft 26, and the upper ends of two linear members 29 made of nylon wire or the like are attached to both ends of the suspension plate 28, respectively. Attached to the lower ends of these wire members 29 are both ends of a round heel resting rod 30 made of a light material such as an aluminum alloy. Note that the two wire members 29 have the same length. Further, strain gauges 31a to 31d are attached to the upper and lower surfaces of the suspension plate 28,
These gauges 31a to 31d are connected to a strain meter (not shown).

Next, a method of measuring the slip resistance coefficient using this slip tester will be explained.

First, the rotating table 9 is leveled, and the anti-slip material 4 for stairs to be measured is attached to the rotating member 18. At this time, the tread surface 4a of the anti-slip material 4 is horizontal, and the tip of the tread surface 4a is positioned on the shaft 8 side. Next, by rotating the rotating member 18 while looking at the scale 19 and the scale support 20, the tread surface 4a is tilted at an angle with respect to the horizontal plane. Note that this angle is made equal to the desired contact angle between the sole and the anti-slip material to be measured.

Next, the vicinity of the toe of the sole of the shoe 5, to which a weight (not shown) of an appropriate weight is attached, is placed on the tip of the tread 4a of the anti-slip material 4, as in the case of actually going down the stairs. do. Further, the heel portion of the sole of the shoe 5 is placed on the heel placement rod 30. At this time, it is confirmed whether the wire material 29 is vertical.

In addition, in this embodiment, since the suspension shaft 26 can be moved along the elongated hole 25, the heel portion can always be appropriately placed on the heel placement rod 30 even for shoes 5 of different sizes. , measurements can be made on a variety of different shoe sizes.

Next, by rotating the nut 27 with respect to the suspension shaft 26, the heel resting rod 30 is moved up and down, and as shown in FIG. Adjust so that the line e-e' connecting the contact part with the bottom is horizontal. Thereby, the contact angle between the anti-slip material 4 and the sole becomes the above-mentioned angle.
Then, if necessary, the verticality of the wire material 29 is confirmed again.

Next, the motor 12 is driven to cause the winding pulley to wind the thread 14, thereby rotating the rotating table 9 very slowly. and,
Due to the rotation of the rotating table 9, the inclination angle θ of the line ee' with respect to the horizontal plane when the shoe 5 starts to slide on the anti-slip material 4, and the linear member 29 suspending the heel of the shoe 5. Find the lowering force Wh. Note that the inclination angle θ can be determined by the scale 23 and the scale support needle 24, and the force Wh is equal to the load acting on the suspension plate 28, so the strain gauge 3
It can be determined by measuring the strains 1a to 31d using the strain meter.

Here, the total weight of the shoe 5 and the weight attached to the shoe 5 is W, the tangential force circle W f is the force exerted on the sole by the anti-slip material 4, and the force circle W _f is the force exerted on the sole by the anti-slip material 4. If the force in the normal direction applied to the shoe sole is W _t and the force in the normal direction applied to the sole from the heel placement rod 30 is W _h , then when the heel part of the shoe sole is placed on the shoe sole as described above, the line If the wire member 29 is vertical, the tangential force acting on the sole from the heel mounting rod 30 is zero (even after the rotating table 9 is rotated and the wire member 29 is tilted). Since the linear member 29 is swingable around the suspension plate 28, even if the shoe 5 tries to move in the tangential direction, no resistance force is applied to the shoe 5 from the heel placement rod 30. (No), anti-slip material 4
The slip resistance coefficient μ between the shoe sole and the shoe sole can be calculated using the following formula.

μ=W _f /W _h =Wsinθ/W・cosθ− _Wh =sinθ/cosθ−C (1) Here, C=W _h /W (2) In addition, evaluation of the slip resistance of anti-slip materials for stairs However, it is necessary to measure the slip resistance coefficient μ at various contact angles (0 to 30 degrees) and check whether the slip resistance coefficient μ shows a high value over the entire range of these contact angles. In this embodiment, the contact angle can be arbitrarily selected by fixing the rotating member 18 at various rotational positions as described above, so that the slip resistance coefficient μ can be easily measured for various contact angles. Can be done.

In addition, in this embodiment, the rotating table 9 is connected to the motor 12.
Since it is rotated by winding the thread 14,
The vibrations of the drive mechanism such as the motor 12 are less likely to be transmitted to the rotating table 9, and the possibility that the vibrations will affect the measurement of the slip resistance coefficient μ can be eliminated.

In addition, since the above formula (1) holds when the weight of the wire member 29 and heel resting rod 30 can be ignored, the wire member 29 and heel resting rod 30 should be arranged as much as possible as in this embodiment. Preferably, it is made of light material.

In addition, in practice, when measuring the slip resistance coefficient μ as described above, instead of using actual shoes,
Test loading plate 3 as shown in Figures 12 and 13
2 with a sole material 33 attached to the back side can be used. Here, the test loading plate 32
A column 34 is erected on the surface of the test plate 32, and a cutout 36 of a weight 35 placed on the test loading plate 32 is fitted into the column 34.

In addition, a spirit level 37 is provided on the surface of the test loading plate 32.
is provided, and the e-
It is now possible to check the horizontality of the e′ line.

FIG. 14 shows another embodiment of the present invention, in which instead of the linear member 29 and heel mounting rod 30 for suspending the heel of the shoe 5 in the previous embodiment, a material with a very low coefficient of friction such as fluororesin is used. The heel resting surface 3 is made of a small material.
8 is provided on a rotary table 9 so that it can be moved up and down and fixed at any position.

Also in this embodiment, if the heel part of the sole is placed on the heel placement surface 38 instead of the heel placement rod 30,
Since the force in the tangential direction acting from the heel resting surface 38 to the sole can be ignored, by detecting the force W _h in the normal direction acting from the heel resting surface 38 to the sole of the shoe by an appropriate means. , the slip resistance coefficient μ can be measured from the above equation (1).

Note that instead of the surface 38 having a very small coefficient of friction, rollers or the like may be used to support the heel portion so that no force is applied in the tangential direction.

Further, each of the above embodiments is an example in which the present invention is applied to a slip tester for stairs. Needless to say, it can also be applied to machines.

As described above, the slip tester according to the present invention measures the slip resistance coefficient between a first object to be measured, such as a non-slip material for stairs, and a second object to be measured, such as a shoe sole, when they come into contact with each other. When doing so, the second measurement object is placed on the first measurement object so as to be in contact with a predetermined portion, and the second measurement object is placed in a portion other than the predetermined portion, By supporting both objects so that no force is applied in the tangential direction, and tilting both objects together in this state until the second object begins to slide, the slip resistance coefficient can be adjusted. By measuring the value of The slip resistance coefficient can be measured,
This provides an excellent effect that is suitable for measuring the slip resistance coefficient in line contact or point contact.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the measurement principle of a conventional slip tester, and Fig. 2 shows the slip resistance coefficient between the anti-slip material for stairs and the sole obtained by the slip tester shown in Fig. 1. An explanatory diagram showing the contact state between the corresponding anti-slip material for stairs and the sole of the shoe, FIG. 3 is an explanatory diagram showing the state of contact between the non-slip material for stairs and the sole of the shoe when actually going down the stairs, and FIG. 4 is a perspective view showing an example of a non-slip material for stairs, FIG. 5 is a perspective view showing an embodiment of the slip tester according to the present invention, FIG. 6 is a front view showing the embodiment, and FIG. A side view showing an example; FIG. 8 is a plan view showing the example; FIG. 9 is a front view showing the suspension plate in the example; FIGS. 10 and 11 are explanatory diagrams showing the measurement method in the example; FIGS. 12 and 13 are perspective views showing test loading plates used in place of actual shoes in the embodiment, and FIG. 14 is a principle diagram showing another embodiment of the present invention. 5...Shoes, 6...Base, 8...Rotating stand shaft, 9...
...Turning table, 12...Motor, 14...Thread, 16...
...Axis, 18...Rotating member, 19...Scale, 20...
...Scale indicator, 21...Fixing screw, 23...Scale, 24...Scale indicator needle, 25...Elongated hole, 26...
... Suspension shaft, 27... Nut, 28... Suspension plate, 2
9... Linear material, 30... Heel placement rod, 31a to 31
d...Strain gauge, 33...Shoe sole material, 38
...Sole placement surface.

Claims (1)

[Scope of Claims] 1. In a slip tester for measuring the slip resistance coefficient between a first object to be measured and a second object to be measured when they come into contact, a base and a horizontal a rotating table rotatably supported around a rotating shaft extending in the direction; a means for detecting a rotation angle of the rotating table; and a rotating table driving device for rotating the rotating table; a first measurement object support device that is provided on the rotating table and fixedly supports the first measurement object;
The other part of the second measurement object, which is provided on the rotary table and partially placed on the first measurement object, is placed on the second measurement object by the second measurement object. A second measurement object that is supported in such a way that even if an object tries to move in the tangential direction of the first measurement object, no resistance force is applied in that direction, or only a negligible amount is applied. A slip tester comprising: a support device; and a load detection device that detects the load of the second measurement object acting on the second measurement object support device. 2 The second measurement object support device includes a measurement object placement member on which the second measurement object is placed, and a wire member that swingably suspends the measurement object placement member. A slip tester according to claim 1, which is formed by: 3. The slip tester according to claim 1, wherein the second measurement object support device has a measurement object placement surface with a small friction coefficient on which the second measurement object is placed. 4 The first measurement object support device includes a rotation member that is rotatable about a rotation axis extending in the horizontal direction and to which the first measurement object is fixed, and an arbitrary The slip tester according to claim 1, 2 or 3, further comprising a fixing means for fixing the rotation angle. 5. Claims 1, 2, 3, or 4, wherein the second measurement object supporting device is capable of moving the position of supporting the second measurement object with respect to the rotating table. Slip tester as described in section.