JPH0389007A - Close plug device for rodless air cylinder - Google Patents

Abstract

PURPOSE: To improve and maintain a seal plug function, and prevent leak of pressure fluid at the time of breakage by providing a seal zone extended on a slot on both sides in a length direction with ball parts which can be engaged with/removed from holding grooves on both sides of the slot, and lip parts to face inclination edge parts of the holding grooves to set the shot in a free condition from a seal holding means. CONSTITUTION: An inner and an outer zones 21, 22 are wider than a width of a center slot 16, and they have flat wall parts 21a, 22a comprising anti- abrasion heat plastic material such as polyurethane or polyester. The wall parts 21a, 22a close to lip parts 29 on side surfaces of the seal zones 21, 22, and respectively facing the inner side and the outer side of a cylinder 10 have holding grooves 25, 26 formed in a cylinder drum part 10 in parallel to the center slot 16 and at an interval in a lateral direction, and leg parts or ball parts 23, 24 in a length direction to be engaged or removed. The holding leg parts 23, 24 of the two seal zones 21, 22 and the inclined seal lip parts 29 are disposed at an interval from the center slot 16, thereby the slot 16 is capable of completely freely sliding a carriage 17.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to fluid-driven rodless cylinders, and more particularly to rodless cylinders of the type with a hollow body or body forming an elongated chamber. This invention relates to a sealing device for air cylinders that do not contain air cylinders. Inside the chamber, a piston member reciprocates, which is connected to a power transmission element through a longitudinally extending slot in the wall of the cylinder.

BACKGROUND OF THE INVENTION Rodless cylinders have long been used for reciprocating motion or positioning objects, typically using a pressurized fluid such as compressed air as a power source.

These rodless cylinders (GB-A-216349
No. 9, EP-A-0147803, US-A-274
No. 5382.

DH-C-046493), unlike traditional cylinders which have a power transmission element protruding from one or both ends thereof, usually have a longitudinally sliding carriage or power transmission element movable on the cylinder body. The power transmission element is directly connected to the piston member inside the cylinder body through a longitudinally extending slot of suitable width. A flexible band-shaped closure element is disposed inside the cylinder chamber and is pressed against the inner wall of the chamber by pressurized fluid to form a closure over the slot. In some cases, a similar sealing strip is provided on the outside of the cylinder body along the longitudinal slot to prevent the ingress of dust. The inner and outer sealing bands pass through the longitudinal passages of the piston and carriage member and are fitted with suitable spreading means to spread apart and bring the respective sealing bands closer to the cylinder body during reciprocating movement of the piston.

(Problems to be solved) GB-A-2163499 and EP-A-01478
According to No. 03, the sealing strip has a sealing portion that forms a plug against the inner wall of the cylinder body adjacent to the longitudinal slot and engages with the inner and outer surfaces of the barrel along said longitudinal slot. and a retaining portion made to do so. The provision of a retaining portion projecting inside the longitudinal slot of the cylinder prevents the power transmission element connected to the reciprocating piston member from being properly guided during the reciprocating movement along the cylinder, as a result of said It becomes impossible to counteract the lateral drag forces acting on the power transmission element. Furthermore, even if the retaining means protrudes into the longitudinal slot, it will not be possible to prevent fluid from leaking out if the sealing portion of the sealing band is damaged. DE-D-8
No. 46493 discloses a V-shaped structure having side surfaces arranged parallel to the radial surface of the longitudinal slot and provided with a longitudinal retaining member projecting into the lateral groove of the cylinder. A sealing device having a sealing band is disclosed, and according to this sealing device, sealing is performed by pressurizing the outer surface of the sealing band against the inner wall of the cylinder near the longitudinal slot between the holding members. be exposed. However, due to the thick central part of the sealing band and the resulting reduced flexibility in the cross-sectional direction, the sealing effect may be reduced, ie, the function may deteriorate due to wear or damage to the sealing band. Still further, if the longitudinal slot and the closure strip are oriented upwardly or placed on the sides, the long closure strip will be removed in a cylinder with a long body if there is no pressurized fluid in the chamber. The problem was that it could not be prevented from falling.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sealing device for a rodless fluid-driven cylinder that solves the problems of conventional sealing devices for rodless cylinders.

The present invention maintains the longitudinal slot in a completely free state, released from the closure retaining means, and provides guide surfaces for the power transmission member on both sides of the slot, while in the absence of pressurized fluid. The object of the present invention is to provide a sealing band for a rodless cylinder, which tightly engages the sealing band with a longitudinal groove in the body. A further object of the present invention is to provide a rodless cylinder having a sealing device that enhances and maintains the sealing function of the holding member and prevents pressurized fluid from leaking even if the sealing band is damaged. .

(Means for Solving Problems) In order to achieve the above object, the present invention provides a body portion having a longitudinal slot formed therein and a side wall extending radially; a piston member that reciprocates within the body portion; A sealing device for a rodless air cylinder comprising a power transmission means operatively connected to the piston member through a slot, the sealing device extending longitudinally at least over the slot and extending longitudinally over the piston member. a first sealing band that freely passes through the passage in the direction; and a first sealing band that is disposed on both sides of the sealing band and that engages with a retaining groove in the body on both sides of the slot.
a seal band holding means having a removable longitudinal bead-like member, and the seal band further includes an inclined lip projecting outward from the longitudinal bead-like member, and an inclined lip portion protruding outward from the longitudinal bead-like member; the bead and the retaining groove having a sealing abutment inner surface projecting inwardly from the bead.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

The general features of rodless air cylinders are described below. As shown in FIG. 1, the air cylinder comprises a hollow body in the form of a body 10, hermetically closed at both ends by two heads or end cups 11, 12, forming a cylindrical chamber 13. A buffer and sealing gasket 15 is provided at both ends inside the cylindrical chamber 13.
The piston member 14 provided with the piston member 14 is adapted to slide. A longitudinally extending slot 16 (see FIG. 4) is formed on one side of the wall of the cylindrical body 10, and this slot is connected to a piston 14 and a stem connected to an external carriage 17 forming a power transmission element. The section 17' is passing through.

The stem 17' and the carriage 17, which extend through the slot 16 towards the piston 14 and are mechanically connected thereto, may be manufactured in any manner and in any shape, e.g. It can also be manufactured and designed by integral die casting or the like to increase mechanical strength.

The cylinder rads 11 and 12 are manufactured separately and are attached to the barrel l, for example by bolts or similar means.

It may also be attached to a valve and may have a confirmation or closure valve. Additionally, each head may include a shock absorbing and decelerating device as seen in conventionally known methods. Such a device may include, for example, an air hole 19.
It has a tube 18 with a suitable sealing gasket (not shown) attached to its free end, which communicates with the piston 14 and has precision threads (not shown) for precise adaptation to the deceleration of the piston 14. . Matching conical holes 20 are formed at each end of the piston 14, and these holes 2
0 into which the tube 18 fits at one end of the piston movement.

Sealing means are provided along the longitudinal slot 16 of the cylinder to seal the inside and outside of the cylinder chamber 13, thereby preventing pressurized fluid from escaping during reciprocating movement of the piston 14. As shown in an enlarged detail in FIG. 4, such closure means are in the form of flexible bands 21, 22 which extend unobstructed in the longitudinal direction formed in the piston 14 and the carriage body. freely pass through the passages.

The inner and outer bands 21 , 22 are flat walls, both of which have a width greater than the width of the central slot 16 and are made of a material capable of withstanding mechanical loads, for example an abrasion-resistant thermoplastic material such as polyurethane or polyester. It has portions 21a and 22a. Lip portion 29 on the side of sealing band 21.22
The four facing walls 21a, 22a on the inner and outer sides of the cylinder 10, adjacent to the inner and outer sides of the cylinder 10, each have a respective retaining groove 25, 26 formed in the cylinder body 10 parallel to and laterally spaced apart from the central slot 16. and longitudinal legs or beads 23, 24 that engage and disengage. In order to avoid overlapping of the retaining grooves 25 of the inner sealing band 21 and the retaining grooves 26 of the outer sealing band 22, the width of the outer sealing band 22 is wider than the width of the inner sealing band 21, as shown in the figure. .

Both the retaining legs 23.24 and the retaining grooves 25.26 have protruding portions or opposing surfaces which are suitably sloped or curved to enhance the sealing effect and to prevent the reciprocating movement of the piston 14. The legs of each seal band are engaged with and separated from the holding groove.

Each of the sealing bands 21 and 22 is formed by molding or extrusion molding a plastic material so that the respective holding legs 23.2
4 is integrally formed. At the same time, during the reciprocating movement of the piston 14 and the power transmission carriage 17, the sealing band 21,
In order to increase their resistance to bending and stretching to which they are subjected, as well as their resistance to normal mechanical compression, both sealing bands 21, 22 are each fitted with a metal plate 27, 28 on the side facing the cylinder body 10. It is being The plates 27, 28 can be attached after each plastic strip is extruded, or alternatively the reinforcing wires 27' can be attached or bonded during molding or extrusion.

As shown in an enlarged view in FIG. 4, the dust-proof sealing effect of the outer sealing band 22 as well as the fluid sealing effect of the inner sealing band 21 is achieved by two raised inclined lips 29 in the longitudinal direction of each sealing band. It is ensured that these beveled lips 29 are perfectly aligned with the corresponding beveled edges 30 of the respective outer surfaces of the retaining grooves 25 , 26 located at a further distance from the central slot 16 . .

As shown in FIG. 4, the holding legs 23.2 of the two sealing bands
4 and an inclined sealing valley 29 are spaced from the central slot 16, which allows the slot 16 to be completely free to slide the carriage 17. Furthermore, by using a sealed band made of thermoplastic material with a metal reinforcing plate bonded to the side facing the slot 16, mechanical bending and stretching loads caused by sliding the carriage 17 on the plastic band can be avoided. Dislodgement is prevented by the metal reinforcing plate, which avoids continuous and dangerous elongation or stretching, while the beveled lip 29 of the plastic sealing strip ensures the sealing action and further improves the operating conditions.

As shown in FIGS. 1 and 2, there are usually two sealing bands 21.
, 22 have their legs 23, 24 engaged in the retaining grooves 25, 26, but only the parts through which the piston 14 and the power transmission carriage 17 pass are fitted with two sealing bands 21, 2.
2 are arranged at intervals so that the piston 14 can reciprocate. At the same time, the piston 14 and the carriage 17 have longitudinal passages 31, 32 which are pointed towards the end of the piston 14, thereby increasing the distance between the sealing bands 21 and 22 during the reciprocating movement of the piston 14. widen or narrow.

A dustproof sealing gasket 33 cooperating with the carriage 17 is mounted around the outer surface of the carriage 17 and presses against an outer sealing strip 22 flush with the cylinder wall. The dust-proof sealing gasket 33 is urged against the outer surface of the cylinder 1-0 and the outer sealing band 22 by a spring 34, and always maintains the cleanliness thereof. The dust-tight sealing gasket 33 may be formed in any shape and may be mounted on the carriage 17 in combination with a plurality of rollers, spheres or similar rotating members 36 (see FIG. 3), if desired. , the rotating member 36 can be mounted on a suitable rotating track provided between the carriage 17 and the opposing surfaces of the cylinder body or hollow body 10 of the cylinder.

As already mentioned, the sealing strips 21, 22 are spaced apart from the central slot 16 in the cylinder 7 position.
[Acts on 10. The central slot 16 thus forms a completely free passage for the shaft or stem 17' connecting the power transmission carriage 17 to the piston 14. This allows the side walls 16a, 16b of the slot throat 16 to be used as mounting and guiding surfaces for the carriage 17 and to withstand the lateral loads acting on the carriage 17. In this case, the carriage 17 is accurately guided during the reciprocating movement of the piston 14, and damage to the cylinder is avoided.

As functionally shown in FIG.
The guiding effect of the carriage 17 can be improved by inserting an anti-friction bar 35 in 7'.

From the above description and the accompanying drawings, it is clear that the closure device according to the invention has a number of advantages over conventional devices. In particular, the use of inclined and curved retaining legs and retaining grooves provides an auxiliary sealing effect by the inclined sound part 29 and a snap-fitting effect of the retaining legs into the retaining grooves.

Furthermore, by using a reinforcing metal plate made to connect to the piston body or power transmission carriage,
The closure band can be manufactured by simple extrusion of a wear-resistant thermoplastic material, such as polyurethane or polyester, i.e., during this extrusion, two lateral slopes each ensure a tight closure on each side of the closure band. Forms a labial seal. In addition, retaining elements in the form of flexible longitudinal legs that engage in retaining grooves parallel to the central slot ensure complete freedom of the central slot and guide the carriage precisely. In addition, even if fluid pressure fluctuates on the holding groove 25 due to incomplete sealing of the sound part 29, the opposing holding groove 2
Since the legs 23 of the inner seal band 21 are pressurized against the wall surface of the valve 5, the pressurized fluid will not leak to the outside in any case.

This works well when a vibration or continuous lateral load is applied to the cylinder that momentarily causes the lateral lips 29 of each sealing band to disengage from their sealing surface. In this way, an improved closure device is obtained at a relatively low cost.

[Brief explanation of drawings]

The invention will be explained in more detail with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view of a rodless cylinder having a sealing device according to the present invention, FIG. 2 is a partially enlarged view showing details of FIG. 1, and FIG.
Cross-sectional view taken along line 3-3, 10 cylinder body, 11
．． tz cylinder head, 13: chamber, 14: piston, 15: buffer/tight gasket, 16: slot,
17: Power transmission carriage, 17': Stem, 18: Tube, 19: Air hole, 20: Conical hole, 21, 22:
Tight stopper band, 21a, 22a: Wall portion, 23, 24: Leg portion or beads, 25, 26: Retaining groove, 27.28: Reinforcement plate, 27': Reinforcement wire, 29: Sound portion, 30: Incline Edge, 33: Dustproof gasket. 34: Spring, 35: Anti-friction bar, 36 Two-rotation member. ----Co21 Fig, 5 Procedural amendment: '11: Flat bottom December 22, 1997 1, Display of $ 1999 Patent M No. 2 86 2, Name of invention Sealing device for rodless empty streak ring 3 , Relationship to the case of the person making the amendment Patent Applicant's Address and Name: Univers Soceta Bel Azioni 4, Agent 6, Contents of Amendment (1) The scope of the patent claims will be amended as shown in the attached sheet. (2) Add the following between lines 8 and 9 on page 16 of the specification. 5, in addition to the low-friction member 35 slidingly contacting the side walls 16a, 16b of the central slot 16
A low friction member 36' (the reference numeral 36 is used twice in FIGS. 3 and 5) is provided on the side wall of the carriage 17 and slides on the flat guiding surface 26' of the retaining groove 26. . This improves stability against lateral movement of the carriage 17. (3) In the 5th line of page 18 of the specification, the phrase ``Figure 5 is a sectional view showing another embodiment of the present invention'' was replaced with ``Figure 5 is a sectional view showing another embodiment of the present invention.''
"A cross-sectional view showing an enlarged part of the cross-sectional view in the figure." Above (Attachment) Claim 1 includes: a body having a radially extending side wall and having a longitudinal slot formed therein; a piston member that reciprocates within the body; and a piston member that is operable through the slot. A sealing device for a rodless air cylinder having a power transmission means connected to a rodless air cylinder, the sealing device comprising:
at least one first sealing strip extending longitudinally over the slot and freely passing through a longitudinal passage formed in the piston member; and retaining means for the seal band, which has bead-like members that can be engaged with and detached from holding grooves formed in the body on both sides of the body, and further, the seal band has a bead-shaped member in the longitudinal direction. The bead-shaped part and the retaining groove are formed into a bead-shaped member. A closure device characterized in that it has a sealing abutment inner surface projecting from the closure. 2. A second sealing band is attached to the outer surface of the slot, and the second sealing band has a longitudinal holding spherical portion that can be engaged with and detached from a longitudinal holding groove on the outside of the body, and The seal according to claim 1, wherein the second outer seal band is larger than the inner seal band, and the outer holding grooves are arranged at a wider interval than the inner holding grooves. Device. 3. Claim characterized in that the spherical part of the sealing band and the retaining groove on the side facing the central slot of the cylinder have portions that protrude oppositely and have surfaces that are sloped or curved in agreement with each other. The sealing device according to item 1 or 2. 4. The sealing device according to claim 1 or 2, wherein each sealing band has reinforcing means. 5. A sealing device according to claim 4, characterized in that said reinforcing means comprises a longitudinally extending metal plate on the side of the intermediate wall facing the central slot of the cylinder. 6. The sealing device according to claim 5, characterized in that a metal reinforcing plate is disposed between the longitudinal holding portions of the sealing band. 7. The sealing device according to claim 4, wherein the reinforcing means includes a reinforcing wire embedded in the sealing band. 8. The power transmission means has a carriage that slides on the outer surface of the cylinder body, a dustproof gasket is attached around the carriage, and the above-mentioned 3. The sealing device according to claim 1, further comprising a biasing means for biasing the dustproof gasket. 9. The sealing device according to claim 8, further comprising a guide means for said power transmission carriage. 10. A closure device according to claim 9, characterized in that said guide means comprises an anti-friction member mounted between the connecting stem of said carriage and the side wall of said longitudinal slot. 11. A closure device according to claim 9, characterized in that said guide means have a sliding track for a rotating element between opposing surfaces of said cylinder body and power transmission carriage. 12. The sealing device according to claim 9, further comprising a low-friction member between the side surface of the carriage and the side surface of the holding groove of the sealing band.

Claims (1)

[Scope of Claims] 1. A body having a radially extending side wall and having a longitudinal slot formed therein, a piston member reciprocating within the body, and operatively connected to the piston member through the slot. In a sealing device for a rodless air cylinder having a power transmission means, the sealing device includes:
at least one first sealing strip extending longitudinally over the slot and freely passing through a longitudinal passage formed in the piston member; and retaining means for the seal band, which has bead-like members that can be engaged with and detached from holding grooves formed in the body on both sides of the body, and further, the seal band has a bead-shaped member in the longitudinal direction. and an inclined edge formed on an outer surface of the holding groove, and the bead-like part and the holding groove protrude from the bead-like member. A sealing device characterized in that it has a sealing abutting inner surface. 2. A second sealing band is attached to the outer surface of the slot, and the second sealing band has a longitudinal holding bead that can be engaged with and detached from a longitudinal holding groove on the outside of the body; Further, the second outer sealing band is larger than the inner sealing band, and the outer holding grooves are arranged at a wider interval than the inner holding grooves. Sealing device. 3. A claim characterized in that the beads and the retaining groove of the sealing band on the side facing the central slot of the cylinder have portions that protrude oppositely and have surfaces that are sloped or curved in agreement with each other. The sealing device according to item 1 or 2. 4. The sealing device according to claim 1 or 2, wherein each sealing band has reinforcing means. 5. A sealing device according to claim 4, characterized in that said reinforcing means comprises a longitudinally extending metal plate on the side of the intermediate wall facing the central slot of the cylinder. 6. The sealing device according to claim 5, wherein a metal reinforcing plate is disposed between the holding beads in the longitudinal direction of the sealing band. 7. The sealing device according to claim 4, wherein the reinforcing means includes a reinforcing wire embedded in the sealing band. 8. The power transmission means has a carriage that slides on the outer surface of the cylinder body, a dustproof gasket is attached around the carriage, and the above-mentioned 3. The sealing device according to claim 1, further comprising a biasing means for biasing the dustproof gasket. 9. The sealing device according to claim 8, further comprising a guide means for said power transmission carriage. 10. A closure device according to claim 9, characterized in that said guide means comprises an anti-friction member mounted between the connecting stem of said carriage and the side wall of said longitudinal slot. 11. A closure device according to claim 9, characterized in that said guide means have a sliding track for a rotating element between opposing surfaces of said cylinder body and power transmission carriage.