JPS62215844A - Tape type apparatus for measuring dynamic friction coefficient - Google Patents

Abstract

PURPOSE:To perform simple and accurate measurement, by setting the tension and speed of a tape running while contacting with an article to be measured and operating dynamic friction coefficient from the tensions of the running tape in the inlet side and outlet side of the article to be measured and the actual speed thereof. CONSTITUTION:The magnetic tape 11 sliding with an article 10 to be measured runs from a supply side reel 12 to a take-up side reel 13, and a tension controller 14, an inlet side tension detector 15, an outlet side tension detector 16, a tape running speed controller 17 and an actual running speed detector 18 are successively arranged in the running route. The article 10 to be measured is mounted on the moving stand 10 positioned between the detectors 15, 16 in a detachable manner and the lap angle of the article 10 to be measured and the tape 11 is changed by the positional control of the moving stand 19. The tension and running speed of the tape 11 are adjusted to set values by the controllers 14, 17 and the outputs of the detectors 15, 16, 18 are inputted to an operation means and operated to make it possible to accurately measure the dynamic friction characteristic of the article 10 to be measured to the magnetic tape 11.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to an apparatus for measuring the coefficient of dynamic friction of a material that comes into sliding contact with a running tape such as a magnetic tape.

[Prior art and its problems] For example, in a magnetic head, the surface that comes into contact with the magnetic tape is made of a combination of various magnetic materials and non-fii materials. Dynamic friction characteristics are important for understanding the durability and changes in characteristics of various equipment such as tape recorders and VTRs, as well as characteristics against magnetic tape.To do this, it is necessary to accurately understand the coefficient of kinetic friction.However, in the past, these No device was known that could continuously and easily measure the coefficient of dynamic friction of sliding materials.

``Object of the Invention'' In view of the current situation, an object of the present invention is to provide a device that can easily measure the coefficient of dynamic friction of a running tape.

``Summary of the Invention J'' The present invention focuses on the fact that the coefficient of dynamic friction can theoretically be measured using Euler's formula based on the tension on the entrance and exit sides of a running tape that runs while contacting the object to be measured, and uses this method. A tension setting means for setting the tension of the traveling tape that runs while contacting the object to be measured; a traveling speed setting means for setting the traveling speed of this traveling tape; and two, the actual traveling speed of the traveling tape. A running speed detector that detects: A pair of tension detectors that detect the tension of the running tape on the inlet and outlet sides of the object to be measured; and the dynamic friction coefficient of the object to be measured is calculated from the output of this pair of tension detectors. The device is characterized in that the entire device is composed of arithmetic means.

Embodiments of the Invention FIG. 1 is a diagram showing the configuration of a device for measuring the coefficient of dynamic friction according to the present invention, FIG. 2 is a diagram of its signal processing system, and FIG. 3 is an enlarged view of the vicinity of the object to be measured. Magnetic tape 1 slidingly in contact with object to be measured 10
1 travels from the supply reel 12 to the take-up reel 13, and during this traveling route, there are a tension regulator 14, an inlet tension detector 15, an outlet tension detector 16,
A tape running speed regulator 17 and an actual running speed detector are sequentially arranged. The object to be measured 10 can be attached to and removed from a movable table 19 located at the middle gate of the inlet tension detector 15 and the outlet tension detector 16. This makes it possible to move on the center line between the tension detectors 15 and 16. By adjusting the position of the moving table 19, the wrap angle θ between the object to be measured 1o and the magnetic tape 11 (FIG. 3) It is possible to change the

The tension adjuster 14 adjusts the tension of the magnetic tape 11 (a roller 14a that is pulled, a spring means 14b that biases the roller 14a to move in a direction in which the tension applied to the magnetic tape 1 increases, and the tension of the spring means 4b). Pulse motor to adjust] 4C. Pulse motor 1
4c, the force of the support arm 14d of the spring means 14b changes, thereby changing the tension applied to the magnetic tape 11. The pulse motor 14c is driven by a tension setting device 4e (FIG. 2).

The tape running speed regulator 17 consists of a capstan 17b driven by a capstan motor 17a such as an AC servo motor, and a pinch roller 17c that runs the magnetic tape 11 sandwiched between the capstan +7b. . The rotational speed of the capstan motor 17a can be arbitrarily adjusted by the output of a tape speed setting device 17d (FIG. 2).

The actual running speed detector detects the actual running speed of the magnetic tape 11 by detecting the rotational speed of the roller a and the rotary encoder bT.

The tension detectors 15.16 on the inlet and outlet sides are commercially available, and their outputs are input to the telesion analyzer 20.21. The output of the tension analyzer 20, 21 is input to the calculation means (computer) 23 together with the output of the tachometer 22 which receives input from the actual running speed detector. Arithmetic means 2
3 adjusts the running speed of the cab stan motor 1 fa of the tape running speed regulator 17 to be equal to the set speed based on the actual running speed signal of the magnetic tape 11 fed back through the actual running speed detector and the tachometer 22. control so that Further, the calculation means 23 calculates the output of the tension analyzers 20, 2] and the inclination angle θ of the magnetic tape 1] with respect to the object to be measured 1o.
Based on this, the coefficient of dynamic friction is calculated using the following formula, and the calculation results are displayed on the display 24, printer 25 and X-Y
It is displayed on the plotter 26.

In other words, the dynamic friction coefficient port is connected to the inlet side tension detector 15.
When the tape tension at the outlet tension detector 16 is T1 and 2, u = (loqe(T2/
TI))/(θT[/0).

The wrap angle θ is the magnetic tape 1 stretched linearly between the inlet tension detector 15 and the outlet tension detector 16.
1, the distance β by which the object to be measured]O is moved and the front radius of the object to be measured 10 can be automatically calculated by inputting them into the calculating means 23.

In this apparatus having the above configuration, the object to be measured] O is set between the inlet side tension detector 15 and the outlet side tension detector 16. After setting the tape tension using the tension setting device 74e and setting the tape running speed using the tape speed setting device 17d, the take-up reel 13 and the capstan motor 17a are driven. Then, when the tape speed detected by the actual running speed detector becomes equal to the tape speed set by the tape speed setting device 17d, a measurement start signal is given. Then, the calculation means 23 uses the entrance tension T1 and the exit tension T2 detected by the entrance tension detector 15 and the exit tension detector 16, and the separately calculated wrap angle θ, to calculate the above calculation formula. Based on this, the dynamic friction coefficient of the object to be measured]0 is calculated and outputted to the display 24, printer 25, and XY block 26.

Tension setting device 14e and tape speed setting device +7d
Since the tension and running speed can be set arbitrarily, the coefficient of dynamic friction can be measured under all sliding contact conditions. Furthermore, by changing the position of the object to be measured 10 and performing measurements, more diverse data can be obtained. Data such as the average value and standard deviation of the magnetic tape 11 during its entire running can also be easily obtained by the calculation means 23. It is also possible to measure environmental conditions by comparing the data obtained when the entire snowmaking process in Figure 1 is placed in a constant temperature layer with the data obtained when it is placed under specific conditions. In addition, if a constant temperature layer that can be controlled by a computer is used, the conditions of the constant temperature layer can be automatically controlled by the computer of this device, making it possible to measure the friction coefficient under a wide range of environmental conditions without human intervention. can be done. These data are accurate because there are no individual differences between the measurers, and objective evaluation of sliding contact materials can facilitate material development.

Furthermore, by using different materials for the magnetic tape 11, it is possible to consider combination issues such as compatibility between the magnetic tape 11 and the object to be measured 1o.

"Effects of the Invention" As described above, according to the tape-type friction coefficient measuring device of the present invention, the dynamic friction characteristics of the object to be measured with respect to the running tape can be easily and accurately measured. By accurately investigating the properties of the materials that make up the bond, we can contribute to the development of better sliding contact materials.

[Brief explanation of drawings]

FIG. 1 is a plan view of a tape dynamic friction coefficient measuring device according to the present invention, FIG. 2 is a signal processing system diagram thereof, and FIG. 3 is an enlarged view of the object to be measured and a pair of tension detectors. 10...Object to be measured, 11...Magnetic tape, ]2...
- Supply side reel, 13... Winding side reel, 14...
Tension adjuster, 14e...Tension setting device, 1
5... Entrance side tension detector, 16... Outlet side tension detector, 17... Tape running speed regulator, 1
7d...Tape running speed setter,...Tora running speed detector, 2o, 21...Tension analyzer 23
...Calculating means, 26...X-Y plotter.

Claims (1)

[Claims] Tension setting means for setting the tension of the running tape running while contacting the object to be measured; Running speed setting means for setting the running speed of this running tape; Running speed detector for detecting the actual running speed of the running tape; A pair of tension detectors detecting the tension of the running tape on the inlet side and the outlet side of the object to be measured; and calculation means for calculating the coefficient of kinetic friction of the object to be measured from the outputs of the pair of tension detectors. Tape type dynamic friction coefficient measuring device.