JP2859945B2 - Manufacturing method of sensitivity adjustment device for position detection device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sensitivity adjusting device of a position detecting device for detecting a stroke position of a piston in a hydraulic cylinder.

[Conventional technology]

2. Description of the Related Art Conventionally, a position detecting device for detecting a stroke position of a piston is attached to a hydraulic cylinder such as a hydraulic cylinder or a pneumatic cylinder.

2. Description of the Related Art A conventional position detecting device is configured by disposing a printed circuit board on which a magnetic sensor such as a magnetoresistive element or a Hall element is mounted in a housing made of synthetic resin or the like.

Such a position detecting device is mounted on, for example, the outer peripheral surface of a cylinder tube, and detects a magnetic field of a permanent magnet attached to a piston that slides in the cylinder tube.

That is, the magnetic flux density passing through the magnetic sensor changes according to the position of the piston in the stroke direction (axial direction), and the magnitude of the detection signal output by the magnetic sensor changes accordingly. When the detection signal becomes larger than a preset threshold value, a detection signal which is a signal indicating that the piston has approached the position detecting device is output.

However, in a fluid pressure cylinder, the thickness of the cylinder tube differs depending on the material of the cylinder tube and the pressure of the fluid used. For example, stainless steel has a smaller thickness than an aluminum alloy, and hydraulics have a greater thickness than pneumatics.

When the thickness of the cylinder tube changes in this way, the distance between the position detecting device and the permanent magnet, that is, the distance between the magnetic sensor and the permanent magnet changes, so that the strength of the magnetic field applied to the magnetic sensor changes.

Therefore, if the sensitivity of the position detection device is invariable and constant,
When used for fluid pressure cylinders of different thicknesses, the detection operation width of the position detection device (the width of the detection signal output from the position detection device in the stroke direction of the piston) changes, and a stable detection operation cannot be performed. there were.

For example, if the thickness of the cylinder tube becomes thinner, the detection operation width becomes larger, thereby lowering the detection accuracy. If the thickness becomes too thin, multipoint operation (detection operation occurs multiple times depending on the position in the stroke direction) Do).

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a method of manufacturing a sensitivity adjustment device that can easily adjust the sensitivity of a position detection device.

[Means for solving the problem]

In order to solve the above-mentioned problems, a manufacturing method according to the present invention includes a step of bonding a sheet-shaped body made of a soft magnetic material and a spacer plate made of a synthetic resin plate with an adhesive layer, and Attaching a double-sided tape with, and a step of cutting the sheet-shaped body, the adhesive layer, the spacer plate, and the laminated body composed of the double-sided tape into predetermined dimensions while leaving the mount. It becomes.

[Action]

The sheet-like body and the spacer plate are adhered to each other by the adhesive layer, and a double-sided tape is attached to the sheet-like body to form a laminate.

The laminate is cut leaving the backing portion, so that a number of sensitivity adjusting devices are stuck to the backing.

By peeling off each of the sensitivity adjusting devices from the mount, an adhesive layer is exposed on the surface, and the device is attached to a magnetic sensor or the like using the adhesive layer.

The adjustment plate reduces the magnetic flux passing through the magnetic sensor,
Adjust the sensitivity of the position detection device.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of a sensitivity adjusting device 10 according to the present invention, and FIG.
FIG. 3 is a sectional front view of the position detecting device 2 having the sensitivity adjusting device 10 according to the present invention, and FIG. 3 is a plan view of the sensitivity adjusting device 10.

In FIG. 2, a position detecting device 2 is attached to an outer peripheral surface of a cylinder tube 4 of a fluid pressure cylinder 3, and a piston 5 sliding on an inner peripheral surface of the cylinder tube 4.
It is operated by the magnetic field of the permanent magnet 6 attached to the. The permanent magnet 6 has an N pole or an S pole along the stroke direction of the fluid pressure cylinder 3 (the direction of the arrow M1 in FIG. 1).

The position detecting device 2 includes a housing 11, a printed circuit board 12,
Light emitting diode 13, magnetic sensor 14, sensitivity adjustment device 10,
It is composed of lead wires 17 and the like.

The housing 11 is made of a non-magnetic material such as a synthetic resin, and is formed in a housing or container shape.

A light emitting diode 13, a magnetic sensor 14, a comparator (not shown), and other circuit components are mounted on the printed circuit board 12, and form a detection circuit for detecting the stroke position of the piston 5. The printed circuit board 12 is disposed inside the housing 11, and is fixed by filling a synthetic resin or the like.

The light emitting diode 13 lights up according to the detection state based on the detection signal of the magnetic sensor 14.

The magnetic sensor 14 detects the magnetic field of the permanent magnet 6 and outputs a detection signal according to the strength of the magnetic field. For example, a magnetic resistance element, a Hall element, or the like is used.

The magnetic sensor 14 is arranged so that sensitivity to the magnetic field in the stroke direction of the fluid pressure cylinder 3 (direction of the arrow M1) is maximized.

The lead wire 17 is for outputting a detection signal from the above-described detection circuit and for supplying power to the detection circuit.

The sensitivity adjustment device 10 is attached to the upper surface of the magnetic sensor 14 (the surface opposite to the permanent magnet 6).

In FIG. 1, the sensitivity adjusting device 10 includes an adjusting plate 16, a spacer 15, and double-sided tapes 21 and 22.

The adjustment plate 16 is for reducing the strength of the magnetic field applied to the magnetic sensor 11, is made of a soft magnetic material such as an amorphous alloy, and has a plate shape slightly larger than the area of the magnetic sensor 14.

The spacer 15 is disposed between the adjustment plate 16 and the magnetic sensor 14, and is a plate made of a nonmagnetic material such as a synthetic resin. By setting the thickness of the spacer 15 to an appropriate value, the sensitivity of the position detecting device 2 is adjusted.

The spacer 15 and the adjustment plate 16 are bonded and integrated by a double-sided tape 22 interposed therebetween,
A double-sided tape 21 for adhering to the magnetic sensor 14 is attached to the other surface of 15.

The sensitivity adjusting device 10 is arranged and attached so that the longitudinal direction of the adjusting plate 16 is parallel to the direction of the magnetic field (the direction of the arrow M1) to which the magnetic sensor 14 senses.

 Next, a method for manufacturing the sensitivity adjustment device 10 will be described.

4 to 6 are views showing a manufacturing process of the sensitivity adjusting device 10.

As shown in FIG. 4, first, a rectangle made of, for example, an amorphous alloy having a thickness of about several tens of microns (for example, trade name “Magneseal” manufactured by Tajima Steel Co., Ltd.) and each side having a length of about several centimeters. Sheet 16B, a double-sided tape 22B of the same size as the sheet 16B, a spacer plate 15B made of a synthetic resin plate such as polycarbonate, and a backing sheet 2 on one side.
The double-sided tapes 21B to which 1b is attached are attached in this order to produce a laminate 10B as shown in FIG.

Next, as shown in FIG. 6, the laminated body 10B is placed on a suitable table with the side of the mount 21b facing down, and cut by a single-tooth cutter so as to have the outer shape of the sensitivity adjusting device 10. By using a single-tooth cutter, it is possible to cut neatly without losing the outer shape.

When cutting the laminate 10B, the laminate 10B is cut at a predetermined pitch in the vertical direction along the vertical cutting line M2, and then cut at a predetermined pitch in the horizontal direction along the horizontal cutting line M3. Also, mount 21
Half cut so as not to cut b.

As a result, a large number of the sensitivity adjustment devices 10 are aligned and adhered on the mount 21b.

When attaching the sensitivity adjustment device 10 to the magnetic sensor 14, one sensitivity adjustment device 10 is separated from the laminate 10B by peeling the sensitivity adjustment device 10 from the mount 21b, and the adhesive surface is thereby exposed. Then, it is attached to the surface of the magnetic sensor 14 using the adhesive surface.

FIG. 7 is a diagram showing a state of a magnetic field generated by the permanent magnet 6.

In FIG. 7, a curve Ha indicated by a solid line is a sensitivity adjusting device.
It shows the strength of the magnetic field due to the effective component (the component in the direction of the arrow M1) of the magnetic flux passing through the magnetic sensor 14 when there is no 10.

Further, a curve Hb shown by a broken line shows the strength of the magnetic field due to the effective component of the magnetic flux passing through the magnetic sensor 14 when the sensitivity adjusting device 10 is provided.

According to these curves Ha and Hb, the largest peak directly above the permanent magnet 6 and the two smaller peaks on both sides thereof are:
These peaks respectively appear, but these peaks are smaller when the sensitivity adjusting device 10 is provided than when the sensitivity adjusting device 10 is not provided.

This is because a part of the magnetic flux that has passed through the magnetic sensor 14 passes through the adjustment plate 16, so that the magnetic flux that passes through the magnetic sensor 14 decreases.

The line Ls in FIG. 7 indicates a threshold value for the position detection device 2 to output a detection signal.

As a result, the operation width Eb of the position detection device 2 when the sensitivity adjustment device 10 is provided is equal to the operation width when the sensitivity adjustment device 10 is not provided.
It is smaller than Ea.

That is, the provision of the adjustment plate 16 reduces the operation width of the position detection device 2. As the distance between the adjusting plate 16 and the magnetic sensor 14 decreases, that is, as the thickness of the spacer 15 decreases, the magnetic sensor 14
The magnetic flux passing through is reduced, and the operating width is reduced. Therefore, the sensitivity of the position detecting device 2 can be adjusted by setting the thickness of the spacer 15 appropriately.

Since the strength of the magnetic field applied to the magnetic sensor 14 varies depending on the thickness of the cylinder tube 4 and the strength of the permanent magnet 6, the spacer 15 (spacer plate 15B) may be used in accordance with the specifications of the fluid pressure cylinder 3. ) May be set and the sensitivity of the position detection device 2 may be adjusted.

According to the above-described embodiment, since the sensitivity of the position detecting device 2 can be adjusted by attaching the sensitivity adjusting device 10 to the surface of the magnetic sensor 14, the sensitivity adjustment is extremely easy.

Sensitivity adjusting device using various spacers 15 with different plate thickness
10 may be prepared and selected according to the sensitivity specification of the position detecting device 2.

Also, the laminated body 10B
, The production of the laminate 10B is easy.

In addition, since many sensitivity adjustment devices 10 are finished in a state of being aligned and adhered on the mount 21b, the sensitivity adjustment devices 10 do not fall apart and component management is easy. The sensitivity adjusting device 10 is peeled off from the mount 21b of the laminate 10B and the magnetic sensor 14 is removed.
The mounting work of the sensitivity adjustment device 10 is extremely easy, and the manufacturing cost of the position detection device 2 can be reduced.

In the above-described embodiment, the laminate 10B and the sensitivity adjusting device 1
0 size, shape, quantity, structure, structure of position detecting device 2,
The shape and the like can be variously changed in addition to the above.

〔The invention's effect〕

According to the present invention, it is possible to provide a method of manufacturing a sensitivity adjustment device that can easily perform a sensitivity adjustment device of a position detection device.

In addition, since a large number of sensitivity adjustment devices are aligned and adhered on the backing sheet, the sensitivity adjustment devices do not fall apart and component management is easy. Since the sensitivity adjusting device can be peeled off from the mount of the laminate and used, the mounting work of the sensitivity adjusting device is extremely easy, and the manufacturing cost of the position detecting device can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a sensitivity adjusting device according to the present invention, FIG. 2 is a sectional front view of a position detecting device having the sensitivity adjusting device according to the present invention, FIG. 6 are diagrams showing a manufacturing process of the sensitivity adjusting device, and FIG. 7 is a diagram showing a state of a magnetic field by a permanent magnet. 2 ... Position detecting device, 10 ... Sensitivity adjusting device, 10B ... Laminate, 1
5B: spacer plate, 16B: sheet, 21B: double-sided tape,
21b: Mount, 22B: Double-sided tape (adhesive layer).

Claims (1)

(57) [Claims] 1. A step of bonding a sheet-shaped body made of a soft magnetic material and a spacer plate made of a synthetic resin plate with an adhesive layer, and a step of attaching a double-sided tape with a mount to the outer surface of the spacer plate; Cutting the laminated body composed of the sheet-shaped body, the adhesive layer, the spacer plate, and the double-sided tape to a predetermined size while leaving the backing sheet. Manufacturing method of sensitivity adjustment device.