JPH0713155Y2 - Magnetic proximity switch for piston position detection - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic proximity switch for use in detecting the piston position of a fluid pressure cylinder.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 7 and 8, a magnetic proximity switch for detecting the piston position of a fluid pressure cylinder is often used in the form of a small cylinder (actual application 2). -1033). This proximity switch 30 is provided with a groove 32 having a circular cross-section that matches the outer shape of the proximity switch along the inner cylinder hole on the outer surface of the body 31 of the fluid pressure cylinder. The mounting screw hole 34 is aligned with the open portion 33 of the groove 32, the mounting screw 35 is tightened, and the tip of the mounting screw 35 is pressed against the groove bottom to be fixed.

When the proximity switch 30 is mounted on the body 31 of the fluid pressure cylinder, it is necessary for an operator to align the mounting screw hole 34 with the opening 33 of the groove 32 and then tighten the mounting screw 35. , There was a problem that I had to do the work well.

In order to avoid such a problem, as shown in FIG. 7, a magnetic proximity switch 40 with an indicator lamp has been conventionally used. In this proximity switch 40, since the indicator light accommodating portion 41 is provided in a protruding manner, it is not necessary for an operator to align the mounting screw hole 42 with the opening portion 33 of the groove 32, but as an LE as an indicator light.
Since electronic components such as D, Zener diode, and resistor are incorporated in the indicator light housing portion 41 adjacent to the cylindrical switch housing portion, there is a problem that the total length of the switch becomes long. In particular, this proximity switch becomes long when the switch is mounted in the groove 32 of the body 31 of the cylinder.
The switch protrudes from the groove 32 and should be avoided as much as possible.

The present inventor has studied the above-mentioned problems and has found that they are caused by the use of a metal cylinder having a circular cross section in the switch case. That is, when the switch case 36 made of a metal tube having a circular cross section, which is relatively free from the problems of cost and strength, is used like the conventional proximity switch shown in FIG. The operator installs the mounting screw hole 34 into the groove 3
It is necessary to protect the reed switch 37 by using an insulating sheet 38 and a heat shrinkable tube 39 for measuring the internal insulation, so that the reed switch 37 is not surrounded by the reed switch 37. , LED,
Since there is no space for accommodating electronic parts such as a Zener diode and a resistor, and these parts are incorporated in a position adjacent to the reed switch 37, the total length of the proximity switch becomes long.

[0006]

SUMMARY OF THE INVENTION The technical problem of the present invention is to prevent rotation of the switch body case in the circumferential direction and to attach it to the body of the fluid pressure cylinder more easily. (EN) It is possible to obtain a magnetic proximity switch for a fluid pressure cylinder, which is miniaturized so that its overall length is as short as possible, and which is conveniently mounted in the groove of the body of the cylinder.

[0007]

In order to solve the above problems, the magnetic proximity switch for piston position detection of the present invention is
The switch body case is made of a synthetic resin, and is mainly composed of a cylindrical portion for accommodating the reed switch and a rectangular cylindrical portion continuously arranged in parallel for accommodating electronic parts including the operation display LED. The cylindrical portion is to be fitted in a groove having a circular cross section provided in the body of the fluid pressure cylinder, and the square tube portion is shaped to fill the opening portion by being fitted in the opening portion of the groove of the fluid pressure cylinder. And a reed switch is housed in the cylindrical portion of the switch body case, and an electronic component including an operation display LED is housed in the rectangular tube portion so as to overlap with the reed switch. A solid fixing portion is integrally connected to the front end side of the, and a mounting screw hole is formed in the fixing portion from the side where the square tube portion is provided.

[0008]

When the magnetic proximity switch is mounted in the switch mounting groove of the fluid pressure cylinder, the cylindrical portion of the switch body case is fitted in the groove of circular cross section provided in the body of the fluid pressure cylinder, and at the same time, the square tubular portion is The switch body case is fixed in the groove of the body by fitting it into the open portion of the groove and inserting the mounting screw into the screw hole provided in the solid fixing portion.

When fixed in this manner, the rotation of the cylindrical portion of the switch body case can be prevented by the square tubular portion. Also, because the switch body case is made of synthetic resin, there is no need to insulate the insulation sheet inside the switch body case or to protect the reed switch with a heat-shrinkable tube. By only providing the rectangular tube portion, it becomes possible to provide an accommodation space along the reed switch for accommodating the electronic components including the operation display LED, and the proximity switch is shortened and miniaturized accordingly. The protrusion from the groove is suppressed. Further, an electronic component including an operation display LED is housed in a rectangular tube portion that prevents the switch body case from rotating, thereby eliminating structural waste.

[0010]

1 to 3 show the structure of a magnetic proximity switch for detecting piston position according to the present invention. The switch body case 2 of the proximity switch 1 is made of a synthetic resin, and is mainly provided with a cylindrical portion 2a for accommodating the reed switch 3 and a parallel connection with the cylindrical portion 2a, and mainly includes an operation display LED 4a. Part 4
And a cylindrical portion 2b for accommodating
As shown in FIG. 6, a is formed so as to fit into a groove 22 having a circular cross section provided in the body 21 of the fluid pressure cylinder 20, and the square tube portion 2b is fitted into the opening 23 of the groove 22. The shape is formed so as to fill the open portion 23. Therefore, the surface of the rectangular tube portion 2b of the switch body case 2 is substantially in the same plane as the surface of the body 21 of the cylinder 20.

The cylindrical portion 2a of the switch body case 2
As can be seen from FIGS. 1 and 3, the reed switch 3 is housed in. In addition, the electronic component 4 is housed in the rectangular tube portion 2b so as to overlap the reed switch 3. The electronic component 4 includes an operation display LED 4a, a Zener diode 4b, and a resistor 4c, which are mounted on a substrate 4d and are electrically connected by printed wiring.

The electronic component 4 is housed in the switch body case 2 so as to be superposed on the reed switch 3, but since the switch body case 2 is made of synthetic resin, it is insulated by an insulating sheet or a lead by a heat shrink tube. Switch 3
Does not need to be protected, and it is possible to provide an accommodation space along the reed switch 3 for accommodating the electronic component 4 only by providing the rectangular tube portion 2b that fits into the opening 23 of the groove of the body 21. , The internal space can be effectively used.

A portion of the switch body case 2 corresponding to the operation display LED 4a has a window for visual recognition made of transparent or translucent resin.
In addition, in the switch body case 2 in which the electronic component 4 is housed, resin is injected to fix the respective parts housed therein.

A solid fixing portion 2c is integrally connected to the tip end side of the cylindrical portion 2a accommodating the reed switch 3 and the fixing portion 2c is provided with the square tube portion 2b. A screw hole 5 into which a mounting screw 6 is inserted is opened. In the figure, reference numeral 7 indicates a lead wire led out along the groove 22 of the body 21 of the fluid pressure cylinder.

When the magnetic proximity switch 1 having the above structure is mounted in the switch mounting groove 22 of the fluid pressure cylinder 20, the cylindrical portion 2a of the switch body case 2 is provided in the body 21 of the fluid pressure cylinder and has a circular cross section. Simultaneously with fitting into 22, the rectangular tube portion 2b is fitted into the open portion 23 of the groove, and the mounting screw 6 is screwed into the screw hole 5 provided in the solid fixing portion 2c. By fixing the switch body case 2 in this manner, the rotation of the cylindrical portion 2a of the switch body case can be suppressed by the square tube portion 2b.

Further, since the switch body case 2 is made of synthetic resin, it is possible to easily connect the rectangular tube portion 2b which fits into the opening 23 of the groove 22 of the body to the case. By only providing the rectangular tube portion 2b, the switch main body case 2 can be provided with a rotation preventing function, and at the same time, an accommodation space for accommodating the electronic component 4 along the reed switch 3 can be provided, which is the total length of the proximity switch 1. Can be shortened and miniaturized, and the proximity switch 1 can be prevented from protruding from the groove 22 of the body.

FIG. 4 shows a second embodiment of the magnetic proximity switch according to the present invention. In the magnetic proximity switch 11 of this embodiment, the lead wire 17 led out from the switch body case 12 is led out orthogonally to the groove 22 of the body 21 of the fluid pressure cylinder. Since the other configurations and actions are substantially the same as those of the first embodiment, the same reference numerals are given to the main parts and the description thereof will be omitted. 5 and 6 show the fluid pressure cylinder 2
The state of attachment of the magnetic proximity switches 1 and 11 of the first and second embodiments to the body 21 of No. 0 is shown in FIG.
Is a piston rod, and 25 is a hole for inserting a screw for mounting a fluid pressure cylinder.

[0018]

According to the magnetic proximity switch for detecting piston position of the present invention described in detail above, the switch body case is integrally formed of synthetic resin by connecting the cylindrical portion and the square tubular portion in series. Rotation of the switch body case in the circumferential direction can be prevented by a simple means, and it can be more easily attached to the body of the fluid pressure cylinder, and the reed switch is housed in the cylindrical portion of the switch body case. At the same time, since the electronic parts including the operation display LED are housed in the square tube portion so as to be overlapped with the reed switch, the overall length can be shortened as much as possible, and the overall size can be reduced. Installation can be convenient.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a configuration of a first embodiment of a magnetic proximity switch of the present invention.

FIG. 2 is an end view of the same.

3 is a sectional view taken along the line AA in FIG.

FIG. 4 is a side sectional view showing the configuration of a second embodiment of the magnetic proximity switch of the present invention.

FIG. 5 is a plan view showing how the proximity switches of the first and second embodiments are attached to a fluid pressure cylinder.

FIG. 6 is an end view of the same.

FIG. 7 is a perspective view illustrating a method of attaching a conventional magnetic proximity switch to a fluid pressure cylinder.

FIG. 8 is a sectional view of a conventional magnetic proximity switch.

[Explanation of symbols]

1,11 Magnetic proximity switch, 2,12 Switch body case, 2a Cylindrical part,
2b Square tube part, 2c Fixed part, 3
Reed switch, 4 electronic parts,
4a LED for operation display, 5 mounting screw holes,
20 fluid pressure cylinder, 21 body,
22 groove, 23 open part.

Claims (1)

[Scope of utility model registration request] 1. A switch body case mainly comprising a cylindrical portion for accommodating a reed switch and a rectangular cylindrical portion continuously arranged in parallel for accommodating electronic parts including an LED for operation display. , Made of synthetic resin, the cylindrical portion is fitted in a groove having a circular cross section provided in the body of the fluid pressure cylinder, and the rectangular tube portion is fitted in an opening portion of the groove of the fluid pressure cylinder, The reed switch is formed into a shape that fills the open part, and the reed switch is housed in the cylindrical portion of the switch body case, and the electronic part including the operation display LED is housed in the square tube portion so as to overlap the reed switch. A solid fixing part is integrally connected to the tip side of the cylindrical part accommodating the above, and a mounting screw hole is opened in this fixing part from the side where the square tube part is provided. Magnetic proximity switch piston position detector according to claim.