JPS6211282B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanically simple and highly reliable magnetic measuring device, and in particular to a general-purpose measuring device that is accurate and easy to read when measuring the length of long objects. .

Magnetic scales are generally flat, and a method is used in which a magnetic medium is coated on the scale and a predetermined magnetic scale pattern is recorded.However, demagnetization and demagnetization due to external magnetism or friction, etc. For,
Its uses tended to be limited. Furthermore, because of the flat plate shape, it was difficult to measure the inside of the curved groove.

The present invention eliminates the above-mentioned drawbacks, uses digital display to eliminate visual misreading of long scales, and uses linear scales to increase the amount of slides that can be stored in the device, that is, the maximum length of the slides. It is characterized by the ability to easily perform processing that causes magnetic changes to the length.

An embodiment of the present invention will be described below based on the drawings.

FIG. 1 shows the structure of a sliding scale 1 according to the invention. The linear nonmagnetic base material 2 may be made of metal, resin, or fiber. Magnetic metal wires 3 are wound around this at regular intervals to correspond to conventional printed scales for visual reading. The winding pitch of the magnetic metal wire 3 is arbitrarily set depending on the application. The cross sections of the non-magnetic base material 2 and the magnetic metal wire 3 are not limited to circular shapes, but may also be rectangular shapes. In addition, the surface is coated with resin 4.
This prevents the magnetic metal wire 3 from loosening and changing the winding pitch, and allows smooth sliding during winding.

FIG. 2 shows a digital measuring device using the sliding scale 1. As shown in FIG. The sliding measure 1 is guided by a guide part 5,
It is wound onto the drum 6. Since the winding on the drum 6 can be done in several rows or more in one stage as shown in B, the entire length of the slide measure 1 can be increased. The magnetic detector 7 is installed at a position approximately 0.5 mm away from the running position of the slide measure 1, and when the magnetic metal wire 3 for detection of the slide measure 1 runs in front of the magnetic detector 7, it emits a pulse at each winding pitch. This is counted and the movement dimension is displayed on the display 8. The magnetic detector 7 is a known one using a magnetoresistive element. The drum 6 may be rotated by a hand-cranked type with a handle attached or by a coiled spring used in a conventional tape measure, but the figure shows an electric type in which a motor 10 is operated using a battery 9 as a power source.

FIG. 3 shows a circuit that detects and counts magnetic changes. The output of the magnetic detector 7 is transmitted to the differential amplifier circuit 1.
1. After passing through the waveform shaping circuit 12 and direction discrimination circuit 13, it is counted by the up-down counter 14 and displayed on the display 8.
Display the dimensions.

According to the above method, since the non-magnetic base material 2 has a circular cross-section, it is possible to measure objects whose surface to be measured is curved compared to the flat plate of a normal scale, such as an S-shaped object or the circumferential surface of a groove wheel. When measuring, you can make accurate contact and get accurate measurements. Further, since the magnetic wire 3 is continuously wound in a spiral around the base material 2, it is possible to provide the sliding measure 1 that is easy to manufacture and accurate. The magnetic detection output does not depend on the moving speed of the sliding scale 1, and stable results can be obtained.
The sliding scale 1 is in a non-contact state and does not generate frictional resistance or wear due to movement, so it has a long life, and the discrimination ability of the magnetic detector 7 is 1.
mm or less, and can be used for general purposes.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram of a sliding scale according to the present invention, where A is a plan view and B is a sectional view. FIG. 2 shows an embodiment of a length measuring device using the sliding scale shown in FIG. A is a plan view of the main body, and B is a sectional view of the drum portion. FIG. 3 is a circuit block diagram for counting and displaying magnetic changes. Explanation of symbols 1: Slide measure, 2: Non-magnetic base material,
3: Magnetic metal wire, 4: Resin coating, 6: Drum,
7: Magnetic detector, 8: Display, 11: Differential amplifier circuit, 12: Waveform shaping circuit, 13: Direction discrimination circuit,
14: Up-down counter.

Claims (1)

[Claims] 1. In a method of determining the pull-out position of a slide measure that can be pulled out and rewinded from a drum housed in the main body of the device using a magnetic detector composed of a magnetoresistive element, a line with a circular cross section is attached to the slide measure. What is claimed is: 1. A measuring device characterized by using a non-magnetic material in the form of a shape, winding a magnetic wire material in a spiral shape at regular intervals to cause a magnetic change, and further coating the surface with a resin.