JP2675721B2 - Rodless cylinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rodless cylinder in which a magnetic material is incorporated in a collar member and the displacement movement of a piston can be detected by a magnetic sensor.

[0002]

2. Description of the Related Art In recent years, various types of rodless cylinders have been adopted as a work transfer device in a factory or the like.
This rodless cylinder has the advantage that the occupied area is small and the handling is simple because the cylinder length can be made shorter than the cylinder having a rod.

[0003] By the way, a conventional rodless cylinder is
A piston in which a wear ring as a collar member is attached to both sides of a piston yoke made of a non-magnetized material such as aluminum is disposed in a cylinder, and the slide is slidably displaced along the longitudinal direction thereof while being connected to the piston. Have a table. The upper surface of the cylinder is formed with a slit that communicates the bore with the outside along the moving direction of the slide table. The slit is closed by a seal member that engages with the slide table.
A magnet is attached to the outer peripheral surface of the piston yoke to detect the position of the piston when the slide table to which the work is fixed is slidably displaced along the slit. The magnet is held on the outer peripheral surface of the piston yoke through a magnet holder,
The position of the piston is detected by detecting the magnetic field effect from this magnet by a magnetic sensor provided on the outer surface of the cylinder.

[0004]

However, in the conventional rodless cylinder, in order to attach the magnet to the outer peripheral surface portion of the piston yoke, mechanical processing for forming a recess in the outer peripheral surface portion must be performed. There is Further, since the magnetic sensor for detecting the magnetic field effect from the magnet is usually provided on the outer surface of the cylinder, it is necessary to mount the magnet in close proximity to the magnetic sensor. In order to generate, the pair of magnets must be attached in combination with their polarities. As a result, when assembling the rodless cylinder in a factory or the like, there is a problem that the mounting direction of the magnet to the recess is incorrect.

The present invention has been made in order to eliminate these disadvantages. The magnet for urging the magnetic sensor is preferably held by a set of wear rings as a collar member, and The wear ring is made of, for example, synthetic resin, and one magnet is arranged so as to face the long groove on the one side surface of the cylinder tube, and the other magnet is disposed on the opposite side surface facing the one side surface of the cylinder tube. It is an object of the present invention to provide a rodless cylinder that does not need to be mechanically machined in the piston yoke without erroneous mounting of the magnet by arranging the rod in the long groove.

[0006]

To achieve the above object, the present invention comprises a cylinder and a slide table, the cylinder reciprocating in a cylinder tube and a bore defined in the cylinder tube. And a long groove for mounting a magnetic sensor extending in the longitudinal direction on the outer surface of the cylinder tube is defined, and the slide table is connected to the piston, and at both ends of the piston. recess is attached a set of collar members on one collar member of small Do <br/> Kutomo is that defined in the outer peripheral portion
The magnetic body for urging the magnetic sensor is held by .

Further, according to the present invention, a magnetic body for urging a magnetic sensor is incorporated in the outer peripheral portion of each of the collar members,
The one magnetic body is arranged along the long groove on the one side surface side of the cylinder tube, and the other magnetic body is arranged along the long groove on the opposite side surface facing the one side surface of the cylinder tube. Is characterized by.

[0008]

In the rodless cylinder according to the present invention, the slide table is displaced as the piston reciprocates in the bore defined by the cylinder tube.
In this case, the position of the piston can be detected by detecting the magnetic field from the magnetic body mounted on the end of the piston and incorporated in the collar member with the magnetic sensor mounted in the long groove of the cylinder tube. .

Further, a magnetic body for urging the magnetic sensor is incorporated in each of a set of collar members, one magnetic body is disposed so as to be oriented in a long groove on one side surface of the cylinder tube, and the other magnetic body is arranged. Since the body is arranged so as to face the long groove on the opposite side surface facing the one side surface of the cylinder tube, when assembling the rodless cylinder in a factory or the like, any one of the pistons is inserted in the bore of the cylinder tube. The end may be inserted first, and the piston may be inserted in any direction.

[0010]

Preferred embodiments of the rodless cylinder according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a rodless cylinder according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views of the rodless cylinder shown in FIG. 1, respectively.

The rodless cylinder 10 has a cylinder tube 12 and a slide table 14. A bore 16 extending longitudinally inside the cylinder tube 12
(See FIG. 2), and the bore 16 is in communication with the outside through a slit 18 defined in the end face. As shown in FIGS. 2 and 4, the sensor mounting long groove 20 extending in the longitudinal direction is formed on both side surfaces of the cylinder tube 12.
a, 20b and elongated grooves 20c, 20d for accommodating lead wires, and fluid bypass passages 22a, 22b for centralized piping are also defined to extend in the longitudinal direction.

In FIG. 2, the upper portion of the cylinder tube 12 is provided with first sliding surfaces 24a, 24b which are inclined inward toward the slit 18 side described later. The first
The slit 1 is provided between the sliding surface 24a and the first sliding surface 24b.
8 is defined, and the slit 18 is formed so as to communicate the bore 16 with the outside.

Both ends of the cylinder tube 12 configured as described above are hermetically closed by end caps 40a and 40b in which ports 38a and 38b are defined (see FIG. 1). A magnetic sensor 41 for detecting the position of the slide table 14 by detecting a magnetic field effect from a magnetic body described later at a predetermined portion of the long groove 20a or 20b provided on the side surface of the cylinder tube 12.
Is attached. Note that FIG. 1 shows a state in which the magnetic sensor 41 is mounted in the long groove 20b.

Next, the slide table 14 integrally formed with the piston 70 will be described. As shown in FIGS. 1, 2 and 5, the slide table 14 includes a table portion 44, and a groove 52 extending in the longitudinal direction through the central portion of the slide table 14 is defined in the table portion 44. Is made. A cover member 45 is provided on the upper portion of the table portion 44, and long grooves 46a and 46b are provided on the bottom portion so as to extend in the longitudinal direction.
Supporting members 48a and 48b for supporting the slide table 14 are fitted and fixed to the 6b. The support member 4
8a and 48b are engaged with the first sliding surfaces 24a and 24b of the cylinder tube 12 to guide the slide table 14 when the piston 70 reciprocates and to support a load acting on the slide table 14. Second sliding surfaces 50a, 50b capable of preventing the change in the inner diameter of the bore 16 are provided. The support members 48a and 48b are formed of, for example, a synthetic resin material having excellent wear resistance and low friction resistance.

Between the slide table 14 and the cylinder tube 12, a pair of opposed slidable contact members 54a, 54b which are disposed substantially parallel to the support members 48a, 48b are interposed (FIG. 1, FIG. 1). 2, see FIG. 5). The upper portions of the sliding contact members 54a, 54b are fixed to the elongated holes defined in the slide table 14, while the sliding contact members 54a, 54b are
The lower part of b is branched into an outer side surface portion and an inner side surface portion, and both of the branched front end portions are formed in sliding contact with the upper surface of the cylinder tube 12. Therefore, the sliding contact members 54a, 54
The outer side surface portion of b can prevent dust from entering from the outside, and the inner side surface portion can support the support member 48.
It is possible to prevent the lubricating oil attached to a and 48b from flowing out.

FIG. 5 shows a piston 70 integrally formed with the slide table 14. The piston 70 has a first pressure receiving surface 72 and a second pressure receiving surface 74 on the opposite side,
Cushion seals 76a and 76b are provided therein (see FIG. 3). As shown in FIGS. 2 and 3, a belt separator 78 is provided above the cylindrical piston 70.
The a and 78b are fixed to the piston yoke 80, and the roller 84 arranged above the piston yoke 80 is fixed to the inside of the slide table 14. The roller 84 is for slidingly contacting a second seal member, which will be described later, during the movement of the slide table 14 to facilitate the transfer thereof.

As shown in FIG. 5, the piston yoke 8 is
0, and piston packings 79a and 79b and wear rings (collar members) 81a and 81b are attached to the front and rear ends of the piston, respectively, and the recesses 82a on the outer peripheral surfaces of the wear rings 81a and 81b are attached. , 8
Magnetic bodies 83a and 83b are fitted into 2b. In this case, the wear rings 81a and 81b are formed in substantially the same shape, and the magnetic bodies 83a and 83b are formed in the recesses 82a and 82b defined at predetermined positions on the outer peripheral surfaces of the wear rings 81a and 81b. Since it is incorporated, the wear ring 81 in which the magnetic body 83a (b) is incorporated
When a (b) is attached to the front end portion and the rear end portion of the piston 70, the magnetic body 83a incorporated in one wear ring 81a and the magnetic body 83b incorporated in the other wear ring 81b are on opposite sides. It is arranged so as to point in the direction. The wear rings 81a and 81b are preferably integrally formed of synthetic resin such as polyacetal. The cross-sectional shape of the magnetic bodies 83a and 83b may be a substantially semi-elliptical shape as shown in FIG. 2, or, as shown in FIGS. 7 and 8, a substantially circular cross section or a ring shape, respectively. Magnetic material 89a, 89
b, 91 may be used. The magnetic bodies 83a, 83b,
The shape of 89a, 89b, and 91 makes it possible to change the magnetic field action.

Further, inside the slide table 14, scrapers 85a and 85b for removing dust adhering to the upper surface of a first seal member, which will be described later, are provided at the front and rear ends of the support members 48a and 48b. ing. As described above, the scraper 85a, 85b and the sliding contact member 54a, 54b surround and seal the sliding portion between the support members 48a, 48b. In FIG. 3, reference numeral 86 indicates a passage for a first seal member described later to enter the piston, and reference numeral 87 indicates a cushion ring.

FIG. 6 shows a seal member fitted to the step portions 36a and 36b. The first sealing member 90 includes tongue pieces 92a, 92
b, and bulges 94a, 94b are further provided above the tongue pieces 92a, 92b. The bulges 94a, 9
The engagement piece 9 is directed upward from the base 4b so as to slightly expand.
6a and 96b extend. The bulging portions 94a, 94
b, when the internal pressure is applied to the piston 70,
6a, 36b, and the engagement pieces 96a, 96b engage inner surfaces 98a, 98b for defining the slit 18. This first seal member 90
Is integrally formed of a flexible synthetic resin body as a whole. On the other hand, the second seal member 97 is for closing the slit 18, and is fitted in a groove 99 extending in a longitudinal direction from above the slit 18 defined on the upper end surface of the cylinder tube 12. The first seal member 90
Penetrates into the passage 86 of the piston 70, and both ends thereof together with the second seal member 97 end caps 40a, 4a.
It is fixed to 0b.

Next, the operation of the rodless cylinder 10 configured as described above will be described.

First, at the time of assembling the rodless cylinder 10 in a factory or the like, a pair of wear rings 81a and 81b, which are attached to both ends of the piston 70, have magnetic bodies 83a and 83b for detecting a magnetic field by the magnetic sensor 41.
It can be easily incorporated into the concave portions 82a and 82b.
Therefore, unlike the conventional case, it is not necessary to perform mechanical processing on the piston yoke 80, and it is not necessary to use a holding member such as a holder for a magnetic body, so that the number of parts can be reduced. Also, the wear rings 81a, 81
b are formed to be substantially the same, and the magnetic bodies 83a,
Since 83b is disposed in the recesses 82a and 82b of the wear rings 81a and 81b attached to both ends of the piston 70 so as to be directed in directions opposite to each other, the piston 70 is provided in the bore 16 of the cylinder tube 12. When arranging
It may be inserted inside, and the direction in which the piston 70 is incorporated does not matter. As a result, the magnetic bodies 83a and 83b are different from the conventional ones.
By designating the assembling direction of the piston 70 according to the polarity of 1, the rodless cylinder 10 can be easily assembled without mistaking the assembling direction of the piston 70.

After the rodless cylinder 10 is assembled in this manner, the work is fixed to the upper surface of the slide table 14. When compressed air is introduced from the port 38a, the compressed air presses the first pressure receiving surface 72 through a passage defined inside the cushion ring 87. As a result, the piston 70 is displaced leftward (in the direction of arrow X) in FIG. At this time, since the piston 70 is integrally formed with the slide table 14 via the piston yoke 80, the slide table 14 is displaced along with the piston 70, and is similarly moved to the left side.
At this time, the belt separators 78a and 78b operate to separate the first seal member 90 and the second seal member 97 between the slide table 14 and the piston 70. Therefore, the work placed on the slide table 14 can be transferred to the left side in FIG. When compressed air is introduced into the port 38b, the opposite operation is performed.

When the slide table 14 is displaced, the position of the slide table 14 is detected by the magnetic sensor 41 mounted in the long groove 20b defined on the side surface of the cylinder tube 12. That is,
Piston 7 formed integrally with slide table 14
0 is displaced with the movement of the slide table 14, and wear rings 81a and 81b attached to the piston 70.
Of the magnetic body 8 incorporated in the recesses 82a and 82b on the outer peripheral surface of the
By detecting the magnetic field effect from 3a and 83b by the magnetic sensor 41, the position of the piston 70, in other words, the position of the slide table 14 can be detected. The detection signal detected by the magnetic sensor 41 is introduced into an external device such as a controller via a lead wire.

[0025]

According to the rodless cylinder of the present invention, the following effects can be obtained.

In other words, the slide table is displaced as the piston reciprocates in the bore defined in the cylinder tube. In this case, the position of the piston can be detected by detecting the magnetic field generated by the magnetic substance incorporated in the pair of collar members attached to both ends of the piston with the magnetic sensor attached to the long groove of the cylinder tube. It will be possible.

Further, one magnetic body incorporated in each of the collar members is disposed so as to face the long groove on one side surface side of the cylinder tube, and the other magnetic body faces the one side surface of the cylinder tube. It is arranged so as to face the long groove on the opposite side surface. In this way, since the magnetic bodies are arranged so as to be directed in mutually opposite directions, the cylinder may be inserted into the bore of the cylinder tube from either end. As a result, since the direction in which the piston is installed is not specified by the polarity of the magnet as in the conventional case, there is an effect that the rodless cylinder can be easily assembled without making a mistake in the direction in which the piston is installed.

Further, since the magnetic body can be easily incorporated in the outer peripheral portion of the collar member, mechanical processing as in the conventional case is not required, and a holding member for holding the magnetic body is not required. There is an advantage that the number of points can be reduced and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a rodless cylinder according to an embodiment of the present invention.

FIG. 2 is a sectional view of the rodless cylinder shown in FIG.

FIG. 3 is a sectional view of the rodless cylinder shown in FIG.

FIG. 4 is a perspective view of a cylinder tube constituting the rodless cylinder shown in FIG.

FIG. 5 is a perspective view of a piston and a slide table constituting the rodless cylinder shown in FIG. 1;

6 is a partially omitted longitudinal sectional view showing an engagement state between a first seal member and a slit of the rodless cylinder shown in FIG. 1;

FIG. 7 is a cross-sectional view showing a modified example of a magnetic body.

FIG. 8 is a cross-sectional view showing a modified example of a magnetic body.

[Explanation of symbols]

 10 ... Rodless cylinder 12 ... Cylinder tube 14 ... Slide table 16 ... Bore 18 ... Slit 20a, 20b ... Long groove 41 ... Magnetic sensor 48a, 48b ... Support member 54a, 54b ... Sliding contact member 70 ... Piston 81a, 81b ... Wear ring 82a, 82b ... Recesses 83a, 83b ... Magnetic body 90 ... First seal member 97 ... Second seal member

Front Page Continuation (72) Inventor Naoki Hoshi 4-2-2 Kinnodai, Taniwahara-mura, Tsukuba-gun, Ibaraki SMC Corporation Tsukuba Technology Center (56) References Showa 61-206104 (JP, U) Showa Flat 3-2903 (JP, U) Actually open Sho 61-193204 (JP, U)

Claims (2)

(57) [Claims] A cylinder and a slide table,
The cylinder has a cylinder tube and a piston that reciprocates in a bore defined in the cylinder tube, and has a long groove extending in the longitudinal direction on the outer surface of the cylinder tube for mounting a magnetic sensor. image form, the slide table is connected to the piston, a set collar member is mounted in the opposite ends of the piston
It is, in the one of the collar member even without low, defined on the outer peripheral portion
Magnetic coercive for biasing the magnetic sensor by recesses
A rodless cylinder characterized by being held . 2. The rodless cylinder according to claim 1, wherein a magnetic body for urging a magnetic sensor is incorporated in the outer peripheral portion of each of the collar members, and the one magnetic body is a long groove on one side surface of a cylinder tube. along disposed, the other magnetic bodies rodless cylinder, characterized in that arranged along the long groove of the side surface of the opposite side opposite to the one side surface of the cylinder tube.