JPH041963A - Tension detecting device - Google Patents

Abstract

PURPOSE:To improve the stability for the tape loading/unloading operations by controlling the reference positions of a tension/position converter and a position/electricity converter synchronously with the movement of a tape. CONSTITUTION:An arm 1 and a spring 2 are provided to receive the tension of a tape 7 and to convert it into the position displacement together with a magnet 3 and the Hall elements 4a and 4b which convert the position displacement into an electric signal, and a movable substrate 5 which moves to change the reference positions of the arm 1, the spring 2 and the elements 4a and 4b respectively in response to the position change of the tape 7. Thus the substrate 5 turns according to the movement of the tape 7 even in a tape loading or unloading state. Therefore the tension is always detected. Then the stability is improved for the tape loading/unloading operations.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tension detection device, and particularly to a tape tension detection device for a tape recorder.

[Conventional technology]

Conventionally, in this type of tension detection device, the reference position of the arm and spring, which is a tension-position converter, is fixed on the same board as the arm fulcrum together with the detection element, which is a position-electrical converter. The arm came within the detection range of the detection element only when used.

[Problem to be solved by the invention]

In the conventional tension detection device described above, the reference position is fixed, so the arm does not enter the detection range of the detection element during tape loading and tape unloading.
There is a problem in that it is impossible to detect tape tension, and therefore closed-loop control of tape tension is not possible, making it impossible to stably perform tape loading and unloading.

[Means to solve the problem]

The tension detection device of the present invention includes a tension-position converter that receives tension and converts it into a positional displacement, a position-electrical converter that converts this positional displacement into an electrical signal, and a position of an object whose tension is to be determined. and a reference position converting device that changes the reference positions of the tension-position converter and the position-electric converter in accordance with changes in the tension-position converter and the position-electric converter.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a plan view showing the configuration of an embodiment of the present invention.

This embodiment includes an arm 1 and a spring 2 as a tension-position converter that receives the tension of the tape 7 and converts it into positional displacement;
A magnet 3 and Hall elements 4a and 4b as a position-electrical converter that converts this positional displacement into an electric signal, and an arm 1. Spring 2. It has a movable substrate 5 as a reference position changing device that moves so as to change the reference positions of the Hall elements 4a, 4b.

That is, the post 1b is in contact with the tape 7 at the other end of the arm 1 which constitutes a tension-position converter and has an arm fulcrum 1a fixed on the fixed substrate 6 at one end. Also, the magnet 3 and Hall elements 4a and 4b that constitute a position-electrical converter
For, magnet 3 is on arm 1, while
The spring fulcrum 2a of the spring 2 that supports the Hall elements 4a and 4b and the arm 1 is installed on a movable substrate 5 that is rotatable about the arm fulcrum 1a.

According to this embodiment, the movable substrate 5 also rotates about the arm fulcrum 1a via the spring 2, following the movement of the arm 1. That is, no matter what position the arm 1 moves, the magnet 3 will always exist between the Hall elements 4a and 4b. Therefore, even during tape loading or tape unloading, since the movable substrate 5 rotates as the tape 7 moves, the tension can always be detected.

〔Effect of the invention〕

As explained above, the present invention enables closed-loop control of tape tension during loading and unloading by controlling the reference positions of the tension-position converter and the position-electric converter in synchronization with the movement of the tape. This has the effect of improving the stability of tape loading and tape unloading.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the configuration of an embodiment of the present invention. 1...Arm, 2...Spring, 3...Magnet,
4a. 4b... Hall element, 5... Movable substrate, 6... Fixed substrate, 7... Tape.

Claims (1)

[Claims] A tension-position converter that receives tension and converts it into positional displacement; a position-electrical converter that converts this positional displacement into an electrical signal; and a tension-position converter that converts the tension into an electrical signal; A tension detection device comprising a position converter and a reference position conversion device that changes a reference position of the position-electrical converter.