JPH0742711A - Rodless cylinder - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a rodless cylinder that can reduce the sliding resistance of a piston without increasing the size and is excellent in vertical load resistance. [Structure] Since a part of the vertical load applied to each piston 7 and piston yoke 8 is supported by a cylindrical roller, the vertical load applied to each piston 7 itself is reduced. as a result,
The sliding resistance when each piston 7 moves in the cylinder tube 1 can be reduced, and the work transfer efficiency with respect to the air supply amount is improved. Further, since the cylindrical roller is provided on the lower surface of the piston yoke 8 and supports the vertical load applied to the piston yoke 8, the deflection of the piston yoke 8 due to the vertical load is reduced and the vertical load resistance of the rodless cylinder is improved.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Generally, a rodless cylinder divides a cylinder tube into two pressure chambers by a piston interposed in the cylinder tube, and the pressure fluid is supplied to and discharged from the two chambers to move the piston. . Then, the work is attached to a mount table connected to a piston yoke that moves integrally with the piston, and the work is transported.

As shown in FIGS. 5 and 6, the cylinder tube 51 is formed in a tubular shape, and a slit 52 is formed on the upper side thereof in the axial direction of the cylinder tube 51.
End brackets 53 are respectively fitted to both open ends of the cylinder tube 51, and each end bracket 53 is provided with a supply / discharge port 54 formed so as to project toward the inside of the cylinder tube 51.

Inside the cylinder tube 51, a pair of pistons 55 and a piston yoke 56 interposed between the pistons 55 and integrally movably connected to the pistons 55.
Is housed. Then, piston packings 57 for preventing air from leaking from the pressure chambers are fitted to both outer ends of each piston 55. A part of the piston yoke 56 passes through the slit 52 and the cylinder tube 5
The plate-shaped mount table 58 is connected to the exposed portion of the cylinder tube 51. The mount table 58 is for carrying a work.

Further, the portion of the piston yoke 56 accommodated in the cylinder tube 51 is the cylinder tube 51.
Since the inner diameter of the cylinder tube 51 is smaller than the inner diameter of the cylinder tube 51, a gap is formed between its lower surface and the inner wall of the cylinder tube 51. Therefore, only each piston 55 abuts on the inner wall of the cylinder tube 51, and each piston 55 slides on the inner wall of the cylinder tube 51 when carrying a work. Further, when a vertical load is applied to the mount table 58 in the axial direction of the cylinder tube 51,
The load is applied to each piston 55 via the piston yoke 56.

Cylinder tube 5 of piston yoke 56
1 On the upper surface of the exposed portion, the cylinder tube 5
1, an upper guide groove 59 is provided in the axial direction, and the mount table 58 closes the upper opening of the upper guide groove 59. On the other hand, a lower guide groove 60 is recessed in the axial direction of the cylinder tube 51 on the lower surface of the portion of the piston yoke 56 accommodated in the cylinder tube 51. The guide grooves 59 and 60 are formed so as to be the shallowest in the central portion of the piston yoke 56 and deeper toward both outer sides.

A dustproof belt 61, both ends of which are fixed to the end brackets 53, is stretched along the slits 52 and is inserted into the upper guide groove 59 outside the slits 52. On the other hand, inside the slit 52, a seal belt 62 whose both ends are fixed to the end brackets 53 is stretched along the slit 52 and is inserted into the lower guide groove 60. The seal belt 62 is for preventing air from leaking from the slit 52.

The rodless cylinder thus constructed supplies / exhausts air to / from each pressure chamber defined by the piston 55 and the piston yoke 56, and moves the piston 55 and the piston yoke 56. The mount table 58 connected to the piston yoke 56 also moves integrally with the piston 55 and the piston yoke 56 so that the work can be transported.

However, when a heavy work is transported in this type of rodless cylinder, the load of the work is entirely applied to the sliding contact surface between each piston 55 and the inner wall of the cylinder tube 51, and the sliding resistance of each piston 55 is increased. It gets bigger. That is, the air pressure that opposes the sliding resistance of each piston 55 has to be supplied to the pressure chamber, which is extremely disadvantageous when a work having a large weight is transported.

Further, the piston yoke 56 does not directly contact the inner wall of the cylinder tube 51, and each piston 55
Since it is only connected and supported by, the bending may occur when a large vertical load is applied to the axis of the cylinder tube 51. That is, when the piston yoke 56 is bent, the pistons 55 connected to the piston yoke 56 come into contact with the inner wall of the cylinder tube 51 at an angle with respect to the axis, and the sliding resistance increases. It was

Therefore, as shown in FIG. 7, guide grooves 63 are provided on both side surfaces of the cylinder tube 51 along the axial direction, and the tips of the support arms 64 formed to extend from both sides of the mount table 58 are guided. It is proposed that the groove 53 is slidably engaged. In the rodless cylinder thus configured, the support arm 64
The vertical load applied to the piston yoke 56 and each piston 55 is reduced to improve the vertical load resistance.

[0012]

However, in the rodless cylinder shown in FIG. 7, since the support arm 64 is formed so as to project to the side of the cylinder tube 51, it cannot be used in a narrow place and the place of use is limited. There was a problem that it would be done. Further, since the support arm 64 slides in the guide groove 63 of the cylinder tube 51,
There has been a problem that the sliding resistance increases accordingly.

The present invention has been made to solve the above problems, and its object is to reduce the sliding resistance of a piston without increasing the size of the rod, and to provide a rod excellent in vertical load resistance. To provide a less cylinder.

[0014]

In order to achieve the above object, the invention according to claim 1 forms a slit extending in the axial direction on the outer circumference of the upper portion of the cylinder tube, and enables a piston to move in the cylinder tube. A rodless cylinder that accommodates a piston yoke between the pistons and exposes a part of the piston yoke to the outside of the cylinder tube through the slit to serve as a workpiece mounting portion. The gist of the present invention is that the rotating body is rotatably supported on the lower surface of the cylinder tube in the traveling direction with respect to the inner wall of the cylinder tube.

According to a second aspect of the present invention, a slit extending in the axial direction is formed on the outer periphery of the lower portion of the cylinder tube, a piston is movably accommodated in the cylinder tube, and a piston yoke is arranged between the pistons. In addition, in a rodless cylinder in which a part of the piston yoke is exposed to the outside of the cylinder tube through the slit and used as a mounting portion for the work, on the outer surface of the piston yoke on the slit side, with respect to the inner wall of the cylinder tube, The main point is that the rotating body is supported so as to be rollable in the traveling direction.

[0016]

Therefore, in the invention described in claim 1, since a part of the vertical load applied to each piston and the piston yoke is received by the rotating body, the vertical load applied to each piston itself can be reduced. As a result, it is possible to reduce the sliding resistance when each piston moves in the cylinder tube, and the work transfer efficiency with respect to the air supply amount is improved. Also,
Since the rotating body is provided on the lower surface of the piston yoke and supports the vertical load applied to the piston yoke, the deflection of the piston yoke due to the vertical load is reduced and the vertical load resistance is improved.

The invention according to claim 2 can reduce the vertical load applied to each piston itself even when the work is hung and conveyed. As a result, sliding resistance when each piston moves in the cylinder tube can be reduced, and the work transfer efficiency with respect to the air supply amount is improved. Further, since the rotating body supports the vertical load applied to the piston yoke, the deflection of the piston yoke due to the vertical load is reduced, and the vertical load resistance is improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment embodying the present invention will now be described with reference to FIGS.
It will be described with reference to FIG. As shown in FIGS. 1 and 2, the cylinder tube 1 is formed in a tubular shape, and a slit 2 is formed on the upper side thereof in the axial direction of the cylinder tube 1. End brackets 3 are respectively fitted to both open ends of the cylinder tube 1, and each end bracket 3 is provided with a supply / discharge port 4 formed so as to project toward the inner side of the cylinder tube 1. The slit 2
A dustproof belt 5 made of urethane rubber, both ends of which are fixed to the end brackets 3, is stretched on the outer side of, and a seal belt 6 made of urethane rubber, whose both ends are fixed to the end brackets 3, is provided inside the slit 2. It is stretched.

The dustproof belt 5 is detachably fitted to the upper fitting portion 2a formed outside the slit 2, and the seal belt 6 is detachably fitted to the lower fitting portion formed inside the slit 2. It is supposed to do. Therefore, the seal belt 6 prevents the pressure fluid (air in this embodiment) supplied from the supply / discharge port 4 from leaking from the slit 2, and the dust-proof belt 5 prevents dust and the like from entering the cylinder tube 1. .

Inside the cylinder tube 1, a pair of pistons 7 are interposed, and the pistons 7 are interposed between the pistons 7.
A piston yoke 8 is connected to the piston yoke 8 so that the piston yoke 8 can move integrally therewith. Piston packing 9 is fitted to both outer ends of each piston 5 to prevent air from leaking from the pressure chamber. An insertion recess 10 into which the supply / discharge port 4 can be inserted is provided on the outer surface of each piston 7 facing the supply / discharge port 4. Further, the interior of the cylinder tube 1 is divided into two pressure chambers by the pistons 7 and the piston yokes 8, and air is supplied to and discharged from the supply / discharge ports 4 to / from the pressure chambers so that the pistons 7 and the piston yokes 8 are removed. It is designed to move in the axial direction.

As shown in FIG. 2, the piston yoke 8 has a body portion 8a disposed inside the cylinder tube 1, a head portion 8b exposed to the outside of the cylinder tube 1 through the slit 2, and the body portion 8a. Neck part 8 for connecting to the head part 8b
and c. A plate-shaped mount table 11 serving as a work mounting portion is connected to the head portion 8b. An upper guide groove 12 is provided on the upper surface of the head portion 8b in the axial direction of the cylinder tube 1, and the mount table 11 closes the upper opening of the upper guide groove 12. The upper guide groove 12 is formed so as to be the shallowest in the central portion of the piston yoke 8 and deeper toward each piston 7. Further, the dustproof belt 5 is inserted into the upper guide groove 12 so that the dustproof belt 5 is not caught even if the head portion 8b of the piston yoke 8 moves.

On the other hand, on the lower surface of the body portion 8a of the piston yoke 8, a lower guide groove 13 is formed in the axial direction of the cylinder tube 1.
Is recessed. The lower guide groove 13 is formed in the central portion of the piston yoke 8 so as to be the shallowest.
It is formed deeper toward the side. Further, the seal belt 6 is inserted into the lower guide groove 13, and the body portion 8a
The seal belt 6 is prevented from being caught even when is moved.

At both outer ends of the lower surface of the body portion 8a, a supporter 14 is provided so as to cover a part of the lower opening of the lower guide groove 13.
Is provided. As shown in FIG. 3, the supporter 14 has a plate-shaped supporter body 15 having two through holes 16 formed on each of the left and right sides thereof, and the piston yoke 8 is inserted by bolts 17 inserted into the through holes 16. Is screwed to both outer ends of the lower surface of the. A groove portion 18 is provided in the central portion of the support body 15 from the front side toward the back side, and a pair of left and right shaft supporting holes (in FIG. A plurality of numbers 19 are shown only on the right side in front of the number. Both ends of a shaft 21 in which a cylindrical roller 20 as a rotating body is inserted in the axial direction are inserted into the shaft support hole 19. Then, the cylindrical roller 20 rotates about the shaft 21.

On the other hand, the portion of the inner wall of the cylinder tube 1 corresponding to the supporter 14 is provided with a steel belt 22 in the axial direction.
The steel roller 22 is in contact with the cylindrical roller 20. Therefore, when the body portion 8 a of the piston yoke 8 moves in the cylinder tube 1, the cylindrical roller 20 rolls on the steel belt 22. Further, packings 23 are fitted along the steel belt 22 on both left and right sides of the steel belt 22 to prevent air from leaking from the embedded portion of the steel belt 22.

Next, the operation of the rodless cylinder configured as described above will be described. In FIG. 1, when air is supplied from the left supply / exhaust port 4, each piston 7 and piston yoke 8 move to the right due to the air pressure, and the mount table 11 also moves to the right because it is connected to the piston yoke 8. . Then, in the supporting device 14 screwed to the lower surface of the piston yoke 8, the cylindrical roller 20 moves while rolling the steel belt 22. That is, the cylindrical roller 20
Is pivotally supported by the support main body 15, so that it moves integrally with the piston yoke 8 while rolling on the upper surface of the steel belt 22. On the other hand, the air accumulated in the pressure chamber on the right side increases in air pressure in the pressure chamber when the piston 7 moves to the right side.
Air is discharged from the right supply / discharge port 4.

During the movement of each piston 7 and piston yoke 8, a vertical load due to the weight of the work placed on the mount table 11 is applied to the sliding contact surface between each piston 7 and the inner wall of the cylinder tube 1. Further, this vertical load is also applied to the contact surface between the cylindrical roller 20 and the steel belt 22. That is, the vertical load is distributed and applied to the sliding contact surface of each piston 7 and the contact surface of the cylindrical roller 20, and the vertical load applied to each piston 7 itself is much smaller than that without the supporter 14. Therefore, the sliding resistance of each piston 7 also decreases.

The lower surface of the piston yoke 8 is in contact with the upper surface of the steel belt 22 via the support 14,
Since the supporter 14 supports the vertical load applied to the piston yoke 8, the deflection generated in the piston yoke 8 itself is reduced. Therefore, each piston 7 connected to the piston yoke 8 properly contacts the inner wall of the cylinder tube 1 without tilting with respect to the axis line, so that the sliding resistance does not increase.

When the air is further supplied from the left supply / discharge port 4, the pistons 7 and the piston yoke 8 move to the right inside the cylinder tube 1 and reach the right end of the cylinder tube 1. At this time, the right piston 7
The supply / exhaust port 4 begins to be inserted into the insertion recess 10 formed in the pressure recess, and residual air in the pressure chamber is gradually discharged from only a small gap between the inner peripheral surface of the insertion recess 10 and the outer peripheral surface of the supply / discharge port 4. It Therefore, when the piston 7 comes into contact with the right end of the cylinder tube 1, the residual air in the pressure chamber acts as an air cushion and reduces the impact when the piston 7 comes into contact.

As described above, in the embodiment, since the support 14 having the cylindrical roller 20 is provided on the lower surface of the piston yoke 8, the cylindrical roller 20 receives a vertical load and the vertical load applied to each piston 7 itself is reduced. You can Then, by reducing the vertical load applied to each piston 7, the sliding resistance of each piston 7 can also be reduced. It is especially effective when the vertical load is large.

Further, since the piston yoke 8 rolls the steel belt 22 via the support device 14, the vertical load applied to the piston yoke 8 can be supported by the support device 14, and the deflection of the piston yoke 8 itself can be reduced. can do. Therefore, each piston 7 connected to the piston yoke 8 does not come into contact with the inner wall of the cylinder tube 1 while being inclined with respect to the axis, but properly slides against the inner wall of the cylinder tube 1. That is, it is possible to prevent an increase in sliding resistance that occurs when each piston 7 tilts and comes into sliding contact with the inner wall of the cylinder tube 1. Also in this case, it is particularly effective when the vertical load is large.

Further, in this embodiment, since the supporter 14 as the vertical load resistant member is provided in the cylinder tube 1, it is possible to use the rodless cylinder in a narrow space. That is, the vertical load resistance can be improved even though the rodless cylinder can be used in a narrow space.

The present invention is not limited to the above-described embodiments, but can be embodied with the following modifications without departing from the spirit of the invention. (1) As shown in FIG. 4, when the work W is hung on the mount table 11 and transported, the steel belts 22 are embedded in the inner wall of the cylinder tube 1 on both left and right sides of the slit 2. Then, the supporter 14 may be provided at a position corresponding to the steel belt 22 on the body portion 8a of the piston yoke 8 so as to abut the steel belt 22. Also in this case, the vertical load resistance is improved and the sliding resistance of each piston 7 can be reduced. This is particularly effective when transporting a heavy work piece.

(2) Supporters 14 may be provided on both the lower surface and the upper surface of the body portion 8a of the piston yoke 8. in this case,
It can be used both when the work is placed and used and when the work is suspended. That is, it is not necessary to make two types of rodless cylinders for placing the work and suspending the work.

(3) Instead of the cylindrical roller 20, a spherical roller may be used to form the supporter 14. (4) Instead of screwing the supporter 14 on which the cylindrical roller 20 is installed to the piston yoke 8, the cylindrical roller 20 is installed directly on the lower guide groove 13 of the piston yoke 8 to
0 may roll on the inner wall of the cylinder tube 1.

(5) In this embodiment, the supporter 14 is screwed to both outer ends of the lower surface of the piston yoke 8.
Only one may be screwed in the center of the lower surface of the. Of course, a plurality of screws may be attached so as to cover the entire lower surface of the piston yoke 8.

(6) Instead of burying the steel belt 22 inside the cylinder tube 1, the cylindrical roller 20 may directly roll the inner wall of the cylinder tube 1. (7) In this embodiment, the pistons 7 and the mount table 11 are connected to the piston yoke 8 so as to be integrally movable, but the pistons 7, the mount table 11 and the piston yoke 8 may be integrally formed.

[0037]

As described above in detail, according to the present invention, the sliding resistance of the piston can be reduced without increasing the size, and the vertical load resistance is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the structure of a rodless cylinder of this embodiment.

FIG. 2 shows the rodless cylinder of FIG.
It is sectional drawing seen from the direction.

FIG. 3 is a perspective view showing a supporter.

FIG. 4 is a sectional view showing another example.

FIG. 5 is a sectional view showing a configuration of a conventional rodless cylinder.

FIG. 6 shows the rodless cylinder of FIG.
It is sectional drawing seen from the direction.

FIG. 7 is a sectional view showing a conventional rodless cylinder.

[Explanation of symbols]

1 ... Cylinder tube, 2 ... Slit, 7 ... Piston,
8 ... Piston yoke, 20 ... Cylindrical roller.

Claims (2)

[Claims] 1. A cylinder (1) is formed with a slit (2) extending in the axial direction on the outer periphery of the upper part thereof, and a piston (7) is movably accommodated in the cylinder tube (1). A piston yoke (8) is arranged between the piston yoke (8) and the piston yoke (8).
A part of the cylinder tube (1) is exposed to the outside of the cylinder tube (1) through the slit (2) to serve as a mounting portion for the work, and the inner wall of the cylinder tube (1) is attached to the lower surface of the piston yoke (8). On the other hand, the rodless cylinder is characterized in that the rotating body (20) is rotatably supported in the traveling direction. 2. A cylinder (1) is formed with an axially extending slit (2) on the lower periphery thereof, and a piston (7) is movably accommodated in the cylinder tube (1). A piston yoke (8) is arranged between the piston yoke (8) and the piston yoke (8).
In the rodless cylinder, a part of which is exposed to the outside of the cylinder tube (1) through the slit (2) and used as a mounting portion for a work, on the outer surface of the piston yoke (8) on the slit (2) side, For the inner wall of the cylinder tube (1), the rotating body (2
0) is supported so that it can roll in the traveling direction.