JPH081326Y2 - Hydraulic cylinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a hydraulic cylinder, and is particularly suitable for mounting a magnet on a piston rod in a cylinder equipped with a position detection device using a magnetic sensor. .

(Prior Art) FIG. 7 shows an example of a conventional cushion cylinder device, in which a is a cylinder, b is a cylinder head, c is a piston rod, d is a piston, and e is a bottom.

A head side cushion plunger f and a bottom side cushion plunger g are provided at the positions indicated by P'and Q ', respectively.

Thus, in the conventional cushion device, the flow of the liquid is mechanically restricted to increase the internal liquid pressure to relieve the liquid, or the valve is restricted to adjust the movement of the cylinder to exert the cushion effect. Things are used.

(Problems to be solved by the invention) However, in order to electrically perform the above cushioning effect, a position detecting device in which a magnet is attached to a piston rod and a magnetic sensor is attached to a cylinder is generally used.

In this case, in a pneumatic cylinder, a non-magnetic material such as stainless steel is used for the cylinder tube and a magnet is attached to the piston part, but when the pressure is high like a hydraulic cylinder, the wall thickness becomes large and it becomes expensive.

Further, if the magnet is directly attached to the magnetic substance, there is a problem that the performance of the magnet deteriorates.

It is an object of the present invention to solve the above-mentioned problems and to provide a cylinder equipped with a position detecting device using a magnetic sensor, in which a magnet can be attached to a piston rod very easily like a conventional cushion plunger. is there.

(Means and Actions for Solving the Problems) The present invention has been made in view of the above points, and in a cylinder provided with a position detection device using a magnetic sensor, a magnet case and a collar in which a magnet is housed are provided. Attach the piston to the stepped part of the piston rod, attach the piston, and tighten the nut to fix the magnet to attach the cylinder head side position detection magnet to the piston rod and store the magnet in the hole at the tip. A cylinder bottom side position detection magnet is attached to the piston rod by attaching the non-magnetic shaft to the piston rod end center hole. The conventional piston rod has a stepped portion for the head cushion and a hole for the bottom cushion. To easily attach the magnet to the piston rod using You can

It is also possible to make the magnet case unnecessary by using a magnet whose outer surface is covered with a non-magnetic material such as resin.

(Example) Next, the Example of this invention is described based on drawing.

FIG. 1 shows the structure of a cylinder device with a position detecting device using a magnetic sensor of the present invention.

1 is a cylinder, 2 is a piston rod, 3 is a piston, 4 is a bottom, 5 is a cylinder head, 6 is a nut, 7 is a main seal, 8
Is a collar, 9 is a shaft, 10 and 19 are magnets,
X and Y indicate the head side magnetic sensor and the bottom side magnetic sensor, respectively.

Further, P is a head side magnet mounting portion, and Q is a bottom side magnet mounting portion.

FIG. 2 shows a detailed structure of the cylinder head side position detecting magnet mounting portion P.

In FIG. 2, the cylinder head side magnet 10 is plate-shaped and is housed in non-magnetic magnet cases 11 and 12. These magnet cases 11, 12 and color 8
Is attached to the stepped portion of the piston rod 2, the piston 3 is attached, and the nut 6 is tightened to attach the magnet 10 to the piston rod.

FIG. 3 shows another embodiment of the magnet mounting part,
The magnet is a ring-shaped magnet ring as shown in 13, and magnet cases 15 and 16 having an L-shaped cross section.
The magnet 13 is attached by storing the magnet 13 inside. 17
Indicates color.

FIG. 4 shows another embodiment of mounting the magnet, in which the outer surface of the magnet ring 13 is covered with a non-magnetic material covering material 18 such as Al, Cu or resin.
Magnet case 1 in Fig. 3 by mounting 13
5,16 can be obsolete.

Next, FIG. 5 shows the detailed structure of the mounting portion of the cylinder bottom side position detecting magnet shown by Q in FIG.
In the figure, the cylinder bottom side magnet 19 is housed in the groove of the tip portion of the shaft 9 which is a plate-shaped non-magnetic material, and a collar 20 which is a cylindrical non-magnetic material is mounted and fixed by caulking the tip. The shaft 9 is mounted in a hole at the center of the end of the piston rod 2 and fixed by a pin 21, and the nut 6 is tightened to prevent the pin 21 from coming off.

FIG. 6 shows an embodiment different from that shown in FIG. 5, in which a hole is formed in the center of a shaft 22 made of a non-magnetic material, a magnet 23 is attached to the tip of the hole, and is fixed by a non-magnetic spacer 24. The fixing by the collar 20 as shown in FIG. 5 is unnecessary.

(Effects of the Invention) The present invention is constructed as described in detail above, and uses the stepped portion for the head cushion and the hole for the bottom cushion of the piston rod of the conventional cushion cylinder as it is, and a magnet for detecting the position on the cylinder head side. A magnet for detecting the position of the cylinder bottom side can be mounted very easily.

Therefore, it is possible to obtain a cylinder equipped with a position detecting device using a magnetic sensor, which can inexpensively attach a magnet to the piston rod without increasing the number of machining points of the piston rod and increasing the size of the cylinder. .

In addition, by using a magnet whose outer surface is coated with a non-magnetic material such as resin, the magnet case can be dispensed with and the deterioration of the performance of the magnet can be reliably prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a cylinder with a position detecting device using a magnetic sensor of the present invention, and FIG. 2 is an embodiment of a cylinder head side position detecting magnet mounting portion of FIG. 3 and 4 each show another embodiment. FIG. 5 shows an embodiment of a magnet mounting portion for position detection on the cylinder bottom side, FIG. 6 shows another embodiment of the same, and FIG. 7 shows a conventional cushion cylinder device. 1 ... Cylinder, 2 ... Piston rod 3 ... Piston, 4 ... Bottom 6 ... Nut, 8 ... Collar 9,9 '... Shaft, 10 ... Magnet 11, 12 ... Magnet case 13 ... Magnet ring 15, 16 ... Magnet case, 17 … Color 18… Cover, 19,19 ′… Magnet X… Cylinder head side position detector Y… Cylinder bottom side position detector

Claims (2)

[Scope of utility model registration request] 1. A cylinder (1) having a cylinder head side position detecting device (x) and a cylinder bottom side position detecting device (Y) using magnetic sensors, in which cylinder head side magnets (10), (13) are provided. The non-magnetic magnet cases (11), (12), (15, 16) and the collars (8), (17) housed therein are attached to the piston rod stepped portion, and the collars (8), (17) are attached. By connecting the piston (3) and tightening the nut (6), the cylinder head side position detecting magnets (10) and (13) are attached to the piston rod (2), and the cylinder head side position detecting device (x ) Is formed,
The cylinder bottom side magnets (19), (23) are housed in the holes provided at the tips of the non-magnetic material shafts (9), (22), and the non-magnetic material shafts (9), (22) are pistoned. A cylinder bottom side position detection device (y) is formed by mounting the cylinder bottom side position detection magnets (19), (23) on the piston rod (2) by attaching to the end center hole of the rod (2). A hydraulic cylinder characterized by. 2. A hydraulic cylinder according to claim 1, wherein the outer surface of the magnet (13) is covered (18) with a non-magnetic substance such as Al, Cu, resin, and mounted on the piston stepped portion.