JPH10184608A - Magnet rodless cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the quantity of generated dust so as to prevent the circumference from being polluted by providing a guide member guiding a slider while holding the non-contact state of the slider side with the cylinder tube side. SOLUTION: When air is fed to a first pressure working chamber S1 through the first port 13 of a first end block 3, a piston 5 is rectilinearly moved in the right direction. In this case, by magnetic attractive force applied between piston magnets 18 and slider magnets 33, a slider 6 is moved following to the piston 5. At this time, by a guide member constituted of guide rails 41 and rail engaging blocks 42, the slider 6 is guided along the lengthwise direction of a cylinder tube 2 and the guide rails 41. Further, a fixed clearance is designed between the respective members 31-34 constituting the slider 6 and the outer circumferential face of the cylinder tube 2. This clearance is always insured at movement of the slider, and the non-contact state is held.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnet rodless cylinder.

[0002]

2. Description of the Related Art Conventionally, various rodless cylinders are known. Among them, for example, not only those having slits on the peripheral surface of the cylinder tube but also those having no slits. Here, FIG. 10 shows an example of the latter rodless cylinder.

[0003] The rodless cylinder shown in FIG.
This is a so-called magnet rodless cylinder 101. Both ends of a cylinder tube 102 made of an aluminum alloy are sealed by end blocks 103. A piston 104 is movably accommodated in a space formed inside the cylinder tube 102. The piston 104 includes a plurality of piston magnets 105, a plurality of piston yokes 106, a pair of piston blocks 107, a piston shaft 108, a nut 109, and the like. In addition, this piston 1
04 separates the cylinder tube 102 into two pressure action chambers S1 and S2. Cylinder tube 1
02, a slider 110 made of aluminum alloy
Is movably provided. The slider 110 is
Slider tube 111, pair of slider covers 11
2, a plurality of slider magnets 113, a plurality of slider yokes 114, a pair of wear rings 115, and a pair of scrapers 116. Wearing 115 is generally made of resin. The wear ring 115 plays a role of reducing the sliding resistance of the slider 110 by sliding with the cylinder tube 102. The scraper 116 is generally made of rubber, and is provided outside the wear ring 115.
The scraper 116 plays a role of scraping dust and the like on the outer peripheral surface of the tube 102 by sliding with the cylinder tube 102. A similar magnet rodless cylinder including the wear ring 115 and the scraper 116 is also disclosed in, for example, Japanese Patent Application Laid-Open No. 8-135611.

In the thus configured magnet rodless cylinder 101, when a fluid such as air is supplied to the first pressure action chamber S1 through the first port 117, the piston 104 moves rightward in the drawing. Conversely, when air is supplied to the second pressure action chamber S2 via the second port 118, the piston 104 moves to the left in the drawing. In this case, the piston magnet 105 and the slider magnet 1
13 by the magnetic attraction force acting between the slider 11
0 moves following the piston 104.

The rodless cylinder 101 of this type using the magnets 105 and 113 has an advantage that the amount of air leakage is smaller than that of a slit type cylinder. Therefore, it is often used in a clean room.

[0006]

However, in the magnet rodless cylinder 101, the wear ring 11 is used.
5 and the scraper 116 always slide with respect to the cylinder tube 102. Therefore, the wear ring 115 is relatively softer than the cylinder tube 102.
When the scraper 116 is worn, dust is likely to be generated. In addition, there is a problem in that the dust generated in the sliding portion scatters to the surroundings, thereby lowering the cleanness of the clean room. Therefore, the appearance of a magnet rodless cylinder that generates a small amount of dust has been desired.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a magnet rodless cylinder which generates a small amount of dust and does not pollute the surroundings.

[0008]

According to the first aspect of the present invention, a piston is movably accommodated inside a cylinder tube, and a slider is movable outside the cylinder tube. And the slider side and the cylinder tube side are kept in a non-contact state in a magnet rodless cylinder in which the slider moves following the piston by a magnetic attractive force acting between the two. In addition, the gist of the present invention is a magnet rodless cylinder characterized in that a guide member for guiding the slider is provided.

According to a second aspect of the present invention, in the first aspect, the guide member has a sliding surface, and the sliding surface is formed of a material harder than the cylinder tube and the slider. did.

According to a third aspect of the present invention, in the first or second aspect, the guide member is provided on a guide rail provided on a frame for supporting the cylinder tube and on the slider and on the guide rail. And a rail engaging block that slidably engages with the rail.

[0011] The invention according to claim 4 is the invention according to claims 1 to 3.
In any one of the above, the plurality of guide members are provided at positions separated from each other. According to a fifth aspect of the present invention, in the fourth aspect, the plurality of guide members are provided symmetrically with respect to a center axis of the cylinder tube.

The "action" of the present invention will be described below. According to the first to fifth aspects of the present invention, when the slider outside the cylinder tube moves following the piston, the guide member holds the slider side and the cylinder tube side in a non-contact state, and that state. Guide the slider with. Therefore, the outer peripheral surface of the cylinder tube and the member on the slider side do not slide, and the generation of dust due to the sliding of both members is avoided. Therefore, even if the rodless cylinder is used, the surroundings will not be contaminated.

According to the second aspect of the present invention, even if dust is generated by sliding between the slider and the guide member, the amount of dust is determined by sliding between the outer peripheral surface of the cylinder tube and the member on the slider side. It is slight compared to the case where it occurs.

According to the third aspect of the invention, when the slider including the rail engaging block moves following the piston, the rail engaging block engaging with the guide rail slides along the guide rail. As a result, the slider is guided along the longitudinal direction of the guide rail.

According to the fourth aspect of the present invention, if the plurality of guide members are provided at positions separated from each other, the load applied to the slider is supported at the plurality of positions, so that the slider can be more reliably guided during movement. Is done.

According to the fifth aspect of the present invention, if the plurality of guide members are provided symmetrically with respect to the center axis of the cylinder tube, the load applied to the slider is evenly supported, so that the slider is more likely to move during movement. Guided reliably.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnet rodless cylinder embodying the present invention will be described below in detail with reference to FIGS.

As shown in FIG. 1 and the like, this magnet rodless cylinder 1 includes a cylinder tube 2, end blocks 3, 4, a piston 5, a slider 6, a support frame 7, and the like.

The cylinder tube 2 is a cylindrical metal member (in this embodiment, a tube made of an aluminum alloy). The left end opening of the cylinder tube 2 is sealed by a first end block 3, and the right end opening is sealed by a second end block 4. As a result, a space is formed inside the cylinder tube 2. Each of the end blocks 3 and 4 includes an end cap 11 and an end plate 12 both made of an aluminum alloy. The end cap 11 is screwed into a hole of the end plate 12. The end of the end cap 11 protruding from the hole is further fitted into the opening of the cylinder tube 2. And the end blocks 3, 4
Are erected on the upper surface of the rectangular support frame 7. Accordingly, the cylinder tube 2 is horizontally supported on the upper surface side of the support frame 7.

As shown in FIG. 2, a first port 13 is formed in the first end block 3. This port 13 communicates with the space inside the cylinder tube 2 via the communication passage 14. A second port 15 is formed in the second end block 4. This port 15
It communicates with the space inside the cylinder tube 2 via the communication passage 16.

The piston 5 is movably housed in the space inside the cylinder tube 2. As a result, the space in the cylinder tube 2 becomes two pressure action chambers S1, S2.
Is divided into As shown in FIG. 2, the piston 5 includes a plurality of piston magnets 18, a plurality of piston yokes 19, a pair of piston blocks 20, a piston shaft 21, a nut 22, and the like. Piston magnet 18 and piston yoke 19
Are disk-shaped members each having a through hole at the center.
These members 18 and 19 are arranged alternately, and further, a piston block 20 is arranged outside the members. The piston block 20 also has a through hole at the center. A piston shaft 21 is inserted into each through hole. Both ends of the piston shaft 21 on which the male thread is formed project from the end faces of the piston blocks 20, and a nut 22 is screwed to the both ends. As a result, the members 18, 19, 20 are integrated. The two piston blocks 20 each include a piston packing 23 and a piston wear ring 24. The piston packing 23 and the piston wear ring 24 slide on the inner peripheral surface of the cylinder tube 2 when the piston 5 moves.

As shown in FIGS. 1 to 3, the slider 6
Is movably provided outside the cylinder tube 2. The slider 6 of the present embodiment includes a slider body 3
1, a pair of slider covers 32, a plurality of slider magnets 33, and a plurality of slider yokes 34. However, no wear ring or scraper was used.

The slider main body 31 is made of metal (in this embodiment, made of aluminum alloy) and has a hole at the center. An internal thread is carved on the inner wall surface at both ends of the hole. The slider cover 32 is also a cylindrical metal member (in the present embodiment, made of an aluminum alloy). The slider cover 32 having an external thread formed on the outer peripheral surface thereof is fixed to the slider body 1 by being screwed into both ends of the hole. The inner diameter of the slider cover 32 is set to a value slightly larger than the outer diameter of the cylinder tube 2. The reason is to ensure a predetermined clearance between the slider 6 and the outer peripheral surface of the cylinder tube 2 when sliding.

The slider magnet 33 and the slider yoke 34 are both disk-shaped members having a through hole at the center. The inner diameter of each through hole is also set to a value slightly larger than the outer diameter of the cylinder tube 2. This is also to secure the clearance. Slider magnet 33
The slider yoke 34 includes a pair of slider covers 32.
They are alternately arranged between them. The magnetic pole of the slider magnet 33 is
The opposite of the magnetic pole. Therefore, both magnets 1
A suction force acts between 8, 33.

Slider body 31 constituting slider 6
Has a work mounting stage 35. The work mounting stage 35 is located above the slider body 31 and projects horizontally toward both sides in the width direction of the cylinder tube 2. Further, the slider body 31 is
It has. The overhang portions 36 are provided in a pair on the left and right below the work mounting stage 35. These projecting portions 36 also project horizontally toward both sides in the width direction of the cylinder tube 2.

Next, the rodless cylinder 1 of this embodiment
The structure of the guide member will be described. As shown in FIGS. 1 and 3, the rodless cylinder 1 includes a guide rail 41 that constitutes a guide member. In this embodiment, a plurality of guide rails 41 (specifically, two
Book). The guide rail 41 is straight, rectangular in cross section, and has an equal cross section. The length of the guide rail 41 is substantially equal to the length of the cylinder tube 2. Both guide rails 41 are disposed on the upper surface side of the support frame 7 so as to sandwich the cylinder tube 2. Also, the cylinder tube 2 and each guide rail 41
And are in a parallel relationship. The two guide rails 41 that are separated from each other are provided symmetrically with respect to the center axis of the cylinder tube 2 as shown in FIG. Each of the guide rails 41 is formed of a material harder than the cylinder tube 2 and the slider 6 (specifically, the slider body 31 and the slider cover 32). In this embodiment, since the members 2, 31, and 32 are made of an aluminum alloy, the guide rail 41 is made of a harder material (eg, stainless steel).

On the other hand, the slider 6 has a rail engaging block 42 constituting a guide member. In this embodiment, a plurality of rail engagement blocks 42 (two in detail)
It is. The rail engaging blocks 42 are respectively provided on the lower surfaces of the overhang portions 36 of the slider 6. The rail engagement block 42 has an engagement groove 43 on the lower surface side. The rail engagement block 42 has a substantially U-shaped cross section. The cross-sectional shape of the engagement groove 43 is substantially equal to the cross-sectional shape of the guide rail 41 and is rectangular. These rail engagement blocks 42 are slidably engaged with both guide rails 41. Double rail engagement block 42
Are also separated from each other in the same manner as the guide rail 41. The rail engagement block 42 is provided symmetrically with respect to the center axis of the cylinder tube 2. At least a sliding portion of each of the rail engaging blocks 42 is preferably made of a material harder than the cylinder tube 2 and the slider 6 (specifically, the slider body 31 and the slider cover 32). Therefore, in the present embodiment in which the members 2, 31, and 32 are made of an aluminum alloy, the entire rail engaging block 42 is formed using a harder material (for example, stainless steel).

A ball bearing row (not shown) is formed in the rail engaging block 42 in two columns. These ball bearing rows are provided by rail engagement blocks 42
A bearing peripheral circuit is formed along the longitudinal direction of the rail, and a plurality of steel balls are rollably accommodated in the bearing peripheral circuit. Accordingly, the ball substantially serves as a sliding portion in the rail engaging block 42.

That is, the rodless cylinder 1 of the present embodiment has two guide members including the guide rail 41 and the rail engagement block 42. Since the guide rail 41 is provided on a fixed member such as the support frame 7 and the cylinder tube 2,
It becomes immovable relative to the fixed member. On the other hand, since the rail support block 42 is provided on the slider 6 which is a movable member, the rail support block 42 is relatively movable with respect to the fixed member and the guide rail 41.

Next, the operation of the thus configured magnet rodless cylinder 1 will be described. When air is supplied to the first pressure action chamber S1 through the first port 13 of the first end block 3, the pressure of the air causes the piston 5 to move linearly rightward in FIG. Conversely, when air is supplied to the second pressure action chamber S2 via the second port 15, the pressure of the air causes the piston 5 to move linearly to the left in FIG. In this case, the piston magnet 18
The slider 6 moves following the piston 5 by the magnetic attraction force acting between the slider 6 and the slider magnet 33.

At this time, the guide member including the guide rail 41 and the rail engaging block 42 guides the slider 6 along the longitudinal direction of the cylinder tube 2 and the guide rail 41. As described above, the slider 6 is designed in advance so that a predetermined clearance is provided between each of the members 31, 32, 33, 34 constituting the slider 6 and the outer peripheral surface of the cylinder tube 2. The clearance is always ensured even when the slider 6 moves. That is, the member 3 on the slider 6 side
1-34 and the cylinder tube 2 side are always kept in a non-contact state.

Next, the characteristic effects of this embodiment will be enumerated below. (A) In this embodiment, when the slider 6 moves, the guide member holds the slider 6 side and the cylinder tube 2 side in a non-contact state, and guides the slider 6 in that state. Therefore, the outer peripheral surface of the cylinder tube 2 and the members 31 to 34 on the slider 6 side do not slide, and the generation of dust due to the sliding of the members 2 and 6 is avoided. Therefore, even if the rodless cylinder 1 is used, dust does not scatter around, so that the surroundings are not polluted. For this reason, unlike a conventional product using a wear ring or a scraper, the magnet rodless cylinder 1 suitable for use in a clean room can be realized. The reason why the wear ring and the scraper can be omitted is that the members 31 to 34 on the slider 6 side are omitted.
And the cylinder tube 2 side is always kept in a non-contact state.

(B) In this embodiment, the sliding surface of the guide rail 41 constituting the guide member and the ball which is a substantial sliding portion in the rail engaging block 42 are both formed by the cylinder tube 2 and the slider 6. Is also formed of a hard material. Therefore, even if they slide, they will not be easily scraped off, and no dust will be generated under normal use conditions. Further, even if dust is generated in the portion, the amount of dust is extremely small as compared with that of the conventional product. That is, it can be said that such a configuration has certainly contributed to the reduction of dust.

(C) In the present embodiment, the guide rail 41
The two guide members, which are composed of a rail and a rail engagement block 42, are provided at positions separated from each other. Accordingly, since the load applied to the slider 6 is supported at two places, there is an advantage that the slider 6 is more reliably guided during movement, unlike the case of one place. Therefore, the non-contact state between the cylinder tube 2 side and the slider 6 side is reliably maintained. Therefore, it can be said that such a configuration also contributes to the reduction of dust. Further, when the combination of the guide rail 41 and the rail engagement block 42 is employed, the manufacture of the guide member is relatively easy. This also contributes to cost reduction.

(D) In the present embodiment, the guide rail 41
The two guide members, which are composed of a rail and a rail engaging block 42, are provided symmetrically with respect to the center axis of the cylinder tube 2. Therefore, since the load applied to the slider 6 is equally supported on the left and right, unlike the case of the asymmetric,
There is an advantage that the slider 6 is more reliably guided during the movement. Therefore, the cylinder tube 2 side and the slider 6
The non-contact state with the side is reliably maintained. Therefore, it can be said that such a configuration also contributes to the reduction of dust.

Note that the present invention is not limited to the above-described embodiment, but can be changed to, for example, the following forms. In the above embodiment, the cross-sectional shape of the guide rail 41 and the cross-sectional shape of the engaging groove 43 of the rail engaging block 42 are not limited to a rectangular shape, but can be changed to, for example, a circular cross-sectional shape. .

The guide rail 41 may not be straight but may be curved. The rail engagement block 42 may of course be installed at a position other than the overhang 36 on the slider 6.

The two guide members may be provided asymmetrically. ◎ The number of guide members is not limited to two. For example, in another example of the magnet rodless cylinder 51 shown in FIG. 4, only one guide rail 41 is provided, and the rail engagement block 42 is provided only on the projecting portion 36 on the same side as the guide rail 41. In this way, it is possible to avoid complication of the structure.
However, the configuration of the above embodiment is superior in that the load applied to the slider 6 is more evenly supported. Furthermore, there are three or more guide members (3,4,5,6,
7,8 ...).

In the above-described embodiment, a guide rail 41 having a rectangular cross section as a fixed side engaging portion is provided on the support frame 7 side, and a rail engaging block 42 having a substantially U-shaped cross section as a moving side engaging portion is provided. It was provided on the slider 6 side. Instead of this, another example of the magnet rodless cylinder 6 shown in FIG.
As in 1, the bar-shaped block 62 as the moving-side engaging portion may be provided on the slider 6 side, and the guide rail 63 having a U-shaped cross section as the fixed-side engaging portion may be provided on the support frame 7 side. Even in this configuration, the rod-shaped block 62 is guided by the engagement groove 64 of the guide rail 63 having a U-shaped cross section,
In addition, the slider 6 side and the cylinder tube 2 side are held in a non-contact state.

The rod-shaped block 62 as the moving side engaging portion
Instead of the example of FIG.
The following configuration may be adopted. In another example of the magnet rodless cylinder 71 shown in FIG. 6, a guided ridge 72 having a rectangular cross section as a moving-side engaging portion is provided on the slider 6.
Is formed integrally with the lower surface of the overhanging portion 36 of FIG. These guided ridges 72 are slidably engaged with engaging grooves 64 of a guide rail 63 having a U-shaped cross section as a fixed-side engaging portion. The surface (that is, the sliding surface) of the guided ridge 72 is the cylinder tube 2 and the slider body 31.
It is formed of a material harder than the like. Here, the hard layer 73 is formed by performing a hardening treatment on the sliding surface.
Is formed. In addition, a method of covering the sliding surface with a hard metal layer, a hard ceramic layer, or the like may be used.
Therefore, in this alternative example, the guided ridge 72 having a hard sliding surface is guided by the engaging groove 64 of the U-shaped guide rail 63, and the slider 6 side and the cylinder tube 2 side are in a non-contact state. Is held.

◎ Guide rail 41 as fixed side engaging portion
Instead of the above-described embodiment in which the support frame 7 and the support frame 7 are separate bodies, the following configuration may be adopted. In another example of the magnet rodless cylinder 81 shown in FIG. 7, a guide rail portion 82 having a rectangular cross section as a fixed-side engaging portion is integrally formed on the upper surface of the support frame 7. These guide rail portions 82 are slidably engaged with engagement grooves 43 of a rail engagement block 42 having a U-shaped cross section as a moving-side engagement portion. In this case, the support frame 7 is preferably made of a hard material such as stainless steel.

The slider 92 may be configured like another example of the magnet rodless cylinder 91 shown in FIGS. In the slider 92 of this another example, the annular groove for mounting a wear ring and the annular groove for mounting a scraper, which have been left in the above-described embodiment, are both attached to the slider cover 32.
Are omitted from the inner peripheral surface. Therefore, the entire slider 92 is shortened accordingly. With this configuration, there is an advantage that a large stroke length of the slider 6 can be ensured as compared with the configuration of the embodiment. Further, the weight of the slider 92 can be reduced.

Here, in addition to the technical ideas described in the claims, the technical ideas grasped by the above-described embodiments are listed below together with their effects. (1) The guide member according to claim 1 or 2, wherein the guide member is provided on the fixed side member so as not to be relatively movable with respect to the cylinder tube, and is provided on the slider and relative to the guide rail. A magnet rodless cylinder, comprising a rail engagement block movably engaged.

(2) The magnet rodless cylinder according to claim 2, wherein the cylinder tube and the slider are made of aluminum or an aluminum alloy, and the guide member is made of stainless steel. With this configuration, it is possible to reduce the amount of dust generated, and to reduce the cost because an inexpensive material is used.

(3) The cylinder according to any one of claims 4 and 5, wherein the number of the guide members is two. With this configuration, it is possible to more reliably support the load of the slider while avoiding complication of the configuration.

The technical terms used in this specification are defined as follows. "Fluid: refers to gases such as nitrogen, oxygen, argon, carbon dioxide, hydrogen, and air such as mixtures thereof, as well as liquids such as water, alcohol, oil, and so-called critical fluids."

[0047]

As described in detail above, according to the first to fifth aspects of the present invention, it is possible to provide a magnet rodless cylinder which generates a small amount of dust and does not pollute the surroundings. .

In particular, according to the second aspect of the present invention, the amount of generated dust can be further reduced. Claim 4,
According to the fifth aspect of the invention, the slider is more reliably guided during the movement, so that the non-contact state is reliably maintained.

[Brief description of the drawings]

1A is a plan view of a magnet rodless cylinder according to an embodiment of the present invention, FIG. 1B is a front view thereof, and FIG. 1C is a left end view.

FIG. 2 is a partially broken cross-sectional view taken along line AA of FIG.

FIG. 3 is a cross-sectional view taken along line BB of FIG.

FIG. 4 is a cross-sectional view of another example of a magnet rodless cylinder.

FIG. 5 is a cross-sectional view of another example of a magnet rodless cylinder.

FIG. 6 is a sectional view of another example of a magnet rodless cylinder.

FIG. 7 is a cross-sectional view of another example of a magnet rodless cylinder.

FIG. 8 is a plan view of another example of a magnet rodless cylinder.

FIG. 9 is a partially cutaway sectional view of another example of the magnet rodless cylinder of FIG. 8;

FIG. 10 is a partially cutaway sectional view of a conventional magnet rodless cylinder.

[Explanation of symbols]

1, 51, 61, 71, 81, 91: magnet rodless cylinder, 2: cylinder tube, 5: piston,
6, 92 slider, 7 support frame as a frame, 41 guide rails constituting a guide member, 42
Rail engaging block constituting a guide member, 62: a bar-shaped block constituting a guide member, 63: guide rail constituting a guide member, 72: guided ridge constituting a guide member, 82: guide constituting a guide member Rail section.

Claims (5)

[Claims] A piston is movably accommodated inside a cylinder tube, and a slider is movably provided outside the cylinder tube. The slider follows the piston by a magnetic attraction force acting between the two. A magnet rodless cylinder which is adapted to move, comprising a guide member for guiding the slider while holding the slider side and the cylinder tube side in a non-contact state. 2. The magnet rod according to claim 1, wherein the guide member has a sliding surface, and the sliding surface is formed of a material harder than the cylinder tube and the slider. Less cylinder. 3. The guide member includes a guide rail provided on a frame supporting the cylinder tube, and a rail engaging block provided on the slider and slidably engaged with the guide rail. The magnet rodless cylinder according to claim 1, wherein the cylinder is configured. 4. The magnet rodless cylinder according to claim 1, wherein a plurality of said guide members are provided at positions separated from each other. 5. The magnet rodless cylinder according to claim 4, wherein the plurality of guide members are provided symmetrically with respect to a center axis of the cylinder tube.