JP2001228077A - Instrument and method for measuring friction force - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction force measuring instrument, constituted so as to be capable of measuring the dynamic friction force caused by the rolling contact of a rubber roller with paper and to make the same agree with design condition. SOLUTION: The friction force measuring instrument is equipped with a roller block 14, to which a rubber roller S1 is attached, a servo motor 15 for rotating the rubber roller S1, a base 35 fixedly attached to a paper S2 to bring the paper S2 into contact with the rubber roller S1, a speed-adjusting part 29 and a weight 18 both of which vary the rotational speed of the rubber roller S1 and the contact pressure of the rubber roller S1 to the paper S2 and a load cell 19 for measuring the friction force generated between the rubber roller S1 and the paper S2 by the rotation of the rubber roller, under a condition made variable by the speed adjusting part 29 and the weight 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frictional force measuring device and a frictional force measuring method for measuring a frictional force of a rubber roller or the like for taking out or transporting a medium such as paper.

[0002]

2. Description of the Related Art An automatic teller machine (ATM), an electrophotographic copying machine (PPC), a printer, or the like is provided with a take-out device for taking out a medium such as a bill or a paper, or a carrying device for carrying. In recent years, the processing efficiency in society and offices has been greatly improved by technological improvements in these take-out devices or transfer devices.

In a take-out device or a transfer device, media such as a rubber roller and a rubber belt are separated and taken out one by one from media in a stacked state, and the taken-out medium is conveyed.

By the way, the behavior of the medium to be taken out or the medium to be conveyed depends on the magnitude of the frictional force generated between the mediums and the magnitude of the frictional force generated between the medium and the rubber roller (or rubber belt). Depends on.

For this reason, when designing a take-out device and a transport device, it is necessary to grasp in advance the relationship between the frictional force generated between the rubber roller (or rubber belt) and the medium.

On the other hand, it is generally known that the Coulomb-Amonton's law widely holds for the coefficient of friction of a member. However, when the rubber material comes into contact with a medium such as paper, this rule may not always be obeyed. For example,
The coefficient of friction between the rubber material and the paper changes depending on the contact pressure between the rubber material and the paper, the rotation speed of the rubber material, the ambient temperature of the rubber material, and the like.

For example, JIS-K "Rubber" does not specify a method for measuring the coefficient of friction.

Further, JIS-P8147 “Test method for friction coefficient of paper and paperboard” defines a method of measuring a friction coefficient for contact between “paper” and “paper”. The method of measuring the coefficient of friction is not defined in JIS.

Generally, in accordance with JIS-P8147, a method is adopted in which one of the paper-to-paper contacts is changed to a rubber material for measurement.

In this measurement method, a paper piece is fixedly provided on a horizontal plate, a rubber piece is placed on the paper piece, a weight is placed on the rubber piece, and the weight is pulled by a tension mechanism. There is a method of measuring a coefficient of friction by giving a relative sliding motion between a paper piece and a rubber piece by pulling the paper piece.

Also, a paper piece is fixedly provided on an inclined plate, a rubber piece is placed on the paper piece, and a weight is placed on the rubber piece, and the inclined plate is rotated to be inclined. There is a method of measuring a coefficient of friction by giving a relative sliding motion between a piece of paper and a piece of rubber.

[0012]

However, in the former method, a change in dynamic friction from static friction can be recorded dynamically, but cannot be measured by changing the slip speed structurally.

Further, in the former method, the frictional force is measured by sliding at the surface contact, and does not reproduce the rolling frictional force of a paper feed roller or the like.

On the other hand, the latter method measures the slip angle by the slope method, and cannot measure the dynamic friction coefficient.

What is required in the field of designing a paper take-out device or a paper transport device is the design of a rotating body (or a traveling body) such as a rubber roller (or a rubber belt). This is a measurement, and the specific value is A at a load of about 1N to 20N and 0.1 m / sec to 5 m / sec.
This corresponds to general design conditions in a paper transport device such as a TM, a PPC, and a printer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has a frictional force measurement method capable of measuring a dynamic frictional force due to rolling contact between a rotating body (or a traveling body) and a medium in accordance with design conditions. It is an object to provide an apparatus and a method for measuring frictional force.

[0017]

According to the present invention, in order to solve the above-mentioned problems, a first aspect of the present invention comprises a first attaching means for attaching a rotating or running object to be measured, and a first attaching means for attaching the object to be measured. Drive means for rotating or running, second mounting means for fixedly attaching the medium and contacting the medium with the object to be measured, rotation or running speed of the object to be measured, medium for the object to be measured A variable means for varying at least one of the contact pressure with respect to and the ambient temperature of the measured object, and between the medium and the medium by rotating or traveling the measured object under conditions varied by the variable means. Measuring means for measuring the generated frictional force.

According to a seventh aspect of the present invention, there is provided a first attaching step of attaching a rotating or running object to be measured, and a second attaching step of fixingly attaching a medium and bringing the medium into contact with the object to be measured. And a variable step of changing at least one of the rotation or running speed of the object to be measured, the contact pressure of the object to be measured with the medium, and the ambient temperature of the object to be measured, and conditions changed by the variable step. And measuring the frictional force generated between the medium and the medium by rotating or running the object.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings.

FIG. 1 is a front view showing a frictional force measuring device 1 according to one embodiment of the present invention, and FIG. 2 is a plan view thereof.

The frictional force measuring device 1 has a base plate 2, and legs 3 and 3 made of a vibration-proof rubber are mounted on both sides of the bottom surface of the base plate 2 to block external vibrations. At the center of the upper surface of the base plate 2, support plates 5 and 5 are attached so as to face each other at a predetermined interval. Support plate 5,
The first shaft 4 is provided between the upper ends of the shafts 5. A vertical pendulum 7 is attached to the center of the first shaft 4 via a bearing 6.

A second shaft 8 is provided at the lower end of the vertical pendulum 7, and a block 10 is suspended on the second shaft 8 via a bearing 9. A rod 11 is mounted substantially horizontally on one side of the block 10, and a male screw portion 12 is formed on the outer peripheral surface of the rod 11. A counterweight 13 is screwed onto the male screw portion 12. The counterweight 13 is movable left and right by rotating.

A roller block 14 is attached to the other side of the block 10. Rod 11 and roller block 1
By adjusting the position of the counterweight 13, the weight of the rod 4 can be statically balanced, and the axis of the rod 11 becomes substantially horizontal in the balanced state.

The roller block 14 is provided with a rubber roller S1 as a rotating body which is an object to be measured. A servo motor 15 is attached to the roller block 14, and the shaft of the rubber roller S 1 is connected to the servo motor 15 via a belt 16.

A mounting plate 17 is provided on the roller block 14 at a position vertically above the axis of the rubber roller S1. On the mounting plate 17, a weight 18 as a variable means of different weight is provided. Are selectively placed.
That is, after the right and left balance is achieved by the counterweight 13, the vertical force generated at the contact point P between the rubber roller S1 and a sheet S2 described later becomes the load F of the weight 18.

On the other hand, a load cell 19 made of a piezoelectric element is provided on one end side of the base plate 2. The load cell 19 is mounted on the sub-base 21 and the sub-base 2
1 is mounted on the base plate 2 via a slide guide 20. A hook 23 is provided at the tip of the rod 11, and a measurement hook 24 that engages with the hook 23 is provided at the tip of the load cell 19.

A screw 22 is attached to the sub-base 21, and the screw 22 is screwed into one end surface of the base plate 2. By turning the screw 22, the sub-pace 21 can be moved a small distance in the left-right direction, and the measuring hook 24 of the load cell 19 can be brought into contact with the hook 23 of the rod 11 without play. Due to the contact between the hook 23 and the measuring hook 24, a horizontal component force μF generated when the rubber roller S1 rotates in the direction of the arrow is generated as a tensile force of the load cell 19.

On the other end side of the base plate 2, a base 35 on which a sheet S2 as a medium is placed is provided. One end of the sheet S2 is placed on the base 35. A clamp member 34 for clamping is provided. Further, a radiation thermometer 26 for measuring the temperature of the surface of the rubber roller S1 is provided above the base plate 2.

FIG. 3 is a block diagram showing a drive control system of the measuring device 1.

In the figure, reference numeral 27 denotes a control unit, to which the servomotor 15 is connected via a control circuit.
A switch 28 is connected to the control unit 27, and the rotation of the servomotor 15 is controlled by opening and closing the switch 28.

The servo motor 15 is connected to the control unit 27 via a speed adjuster 29 as a variable means, and the rotational speed of the servo motor 15 is adjusted by the speed adjuster 29.

FIG. 4 is a block diagram showing an information input system of the measuring device 1.

The load cell 19 is connected to a personal computer 33 via an AD converter 31. The analog output of the load cell 19 is AD-converted and taken into the personal computer 33.

The radiation thermometer 26 is connected to a personal computer 33 via a converter 32, and the output of the radiation thermometer 26 is similarly converted and taken into the personal computer 33.

The data taken into the personal computer 33 is output by a known general calculation software as time series data, for example, as a graph as shown in FIG.

Next, a description will be given of a friction force measuring method using the above-described apparatus.

First, without placing the weight 18 on the placing plate 17, the counterweight 13 is adjusted to balance the right and left static around the second axis 8. After a while, placing plate 1
A weight 18 having a desired weight, for example, 1N to 20N is placed on the 7 and the switch 28 is turned on. As a result, the control unit 27 controls the drive motor 15 via the speed adjustment unit 29 to change the desired rotation speed, for example, the sheet speed from 0.1 m / sec to 5 m.
/ Sec is rotated stably at such a speed as to convey at a speed of / sec. Due to this rotation, the rubber roller S1 is rotated via the belt 16, and the dynamic friction force generated between the rubber roller S1 and the paper S2 acts on the load cell 19 as μF. This dynamic friction force is taken into the personal computer 33 via the AD converter 31.
At this time, the rubber roller S is measured by the radiation thermometer 26.
1 is measured and taken into the personal computer 33 as data.

According to this measuring method, the load between the rubber roller S1 and the paper S2 can be changed under various conditions by changing the load of the weight 18, the rotation speed of the drive motor 15, and the ambient temperature of the rubber roller S1. The generated dynamic friction force can be measured.

Therefore, when designing the unloading device or the transporting device, the relationship between the frictional force between the rubber roller S1 and the medium can be grasped in advance, and the reliability can be improved.

FIG. 6 is a block diagram showing a dynamic friction force measuring device according to a second embodiment of the present invention.

The same parts as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In the second embodiment, a rubber belt 41 is used instead of a rubber roller as an object to be measured. The rubber belt 41 includes a driving roller 42 and a driven roller 43
And the drive roller 42 is connected to the drive motor 15 via the belt 16.

When the drive motor 15 is rotated, the belt 1
The rubber belt 41 travels via the drive roller 6 and the drive roller 42, and the dynamic friction force generated between the rubber belt 41 and the sheet S2 is generated in the load cell 19 as μF. This dynamic friction force is converted by the AD converter 3
The data is taken into the personal computer 33 via the PC 1. At this time, the surface temperature of the belt 16 is measured by the radiation thermometer 26, and is taken into the personal computer 33 as data.

According to this measuring method, the load between the rubber belt 41 and the paper S2 can be changed under various conditions by changing the load of the weight 18, the rotation speed of the drive motor 15, and the ambient temperature of the rubber belt 41. Can be measured, and the same operational effects as those of the first embodiment can be obtained.

In the first and second embodiments, the dynamic friction force generated between the rubber roller and the paper is measured. However, the present invention is not limited to this.
With any other material, it is possible to measure the dynamic friction force generated between the rotating body and the fixed surface.

In the first and second embodiments, the rubber roller block 14 is not movable in the vertical direction. However, the present invention is not limited to this.
The rubber roller block 14 may be mounted movably in the vertical direction.

The contact point P of the rubber roller S 1, the axis of the second shaft 8 attached to the vertical pendulum 7,
The 9 measurement hooks 24 are arranged on the same straight line so that no moment is generated by rotation. But,
The diameter of the rollers used in the paper transport device or the like is not uniform. For this reason, in the first and second embodiments, when the diameter of the rubber roller S1 of the measured object is changed, the contact point P of the rubber roller S1, the axis of the second shaft 8, the load cell 1
The 9 measuring hooks 24 are offset, which creates a moment and affects the measured data.

On the other hand, by attaching the rubber roller block 14 so as to be movable up and down, the contact point P of the rubber roller S1, the axis of the second shaft 8, and the measuring hook 24 of the load cell 19 are always in the same direction. It can be arranged on a line, preventing the occurrence of a moment and without affecting measurement data.

[0049]

As described above, according to the present invention, the dynamic frictional force generated between the measured object and the medium can be measured under various conditions, so that the information necessary for the design can be obtained in advance. There is an effect that the reliability of the take-out device or the transfer device can be improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a friction force measuring device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a frictional force measuring device.

FIG. 3 is a block diagram showing a drive control system of the measuring device.

FIG. 4 is a block diagram showing an information input system of the measuring device.

FIG. 5 is a graph illustrating a friction coefficient generated between a rubber roller and a sheet.

FIG. 6 is a configuration diagram showing a friction force measuring device according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rubber roller (rotating body / measured body) 14 ... Roller block (first mounting means) 15 ... Servo motor (driving means) 18 ... Weight (variable means) 19 ... Load cell (measuring means) 29 ... Speed adjusting unit (Variable means) 35 ... base (second mounting means)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yukio Asari 70 Yanagimachi, Yuki-ku, Kawasaki-shi, Kanagawa F-term in Toshiba Yanagimachi Plant (reference) 2F051 AA15 AB01 AB09 AC01 BA00

Claims (10)

[Claims] 1. A first attaching means for attaching a rotating or running object to be measured, a driving means for rotating or running the object to be measured, and a medium fixedly attached, and the medium is attached to the object to be measured. A second mounting means for contacting the object, a rotation or running speed of the object to be measured, a contact pressure of the object to be measured against the medium, and a variable means for changing at least one of the ambient temperature of the object to be measured, Measuring means for measuring a frictional force generated between the medium and the medium by rotation or running of the measured object under the conditions changed by the variable means. . 2. The frictional force measuring device according to claim 1, wherein the rotation or running speed of the object to be measured is adjusted by a speed adjuster. 3. The apparatus according to claim 1, wherein the contact pressure of the object to be measured with respect to the medium is changed by selectively placing weights having different weights on the upper part of the object to be measured. Friction force measuring device. 4. The apparatus according to claim 1, wherein the ambient temperature of the object is detected by a radiation thermometer. 5. The frictional force measuring device according to claim 1, wherein said first mounting means is supported by a supporting means, and is connected to said measuring means via said supporting means. 6. A pendulum which is rotatably attached to a fixed first shaft, and wherein the supporting means is rotatably provided below a pendulum via a second shaft, wherein The measuring means comprises a rod horizontally provided on the other end of the block, and a balance with the first mounting means movably provided on the rod. 6. A balancer for maintaining a balance so as to maintain, and a sensor for detecting, via the rod, a frictional force generated between the medium to be measured during rotation or running of the measured object. Friction force measuring device. 7. A first attaching step of attaching a rotating or running object to be measured, a second attaching step of fixedly attaching a medium and bringing the medium into contact with the object to be measured, and the object to be measured. A variable step of varying at least one of the rotation or running speed of the object, the contact pressure of the object to be measured with the medium, and the ambient temperature of the object to be measured. A measurement step of measuring a friction force generated between the medium and the medium by rotating or running the body. 8. The method according to claim 7, wherein the rotation or traveling speed of the object is adjusted by a speed adjuster. 9. The apparatus according to claim 7, wherein the contact pressure of the object to be measured with respect to the medium is changed by selectively placing weights having different weights above the object to be measured. Friction force measurement method. 10. The method according to claim 7, wherein the ambient temperature of the object is detected by a radiation thermometer.