Cylinder guide mechanism and cylinder with guide mechanism

Abstract

A cylinder guide mechanism (12) attached to a cylinder (14) in which a piston rod (22) performs forward and reverse operations in a tube (16), comprising: a floating sleeve (50) designed to perform forward and reverse operations, following the forward and reverse operations of the piston rod (22); a retaining section (70) designed to hold the floating sleeve (50); a guide mechanism (72) with a guide element (96) which is held by the retaining section (70), and a displaceable element (98) which is held on the guide element (96) and is designed to be displaced relative to the guide element (96); and a clamp (102) designed to connect the movable element (98) and the tube (16).

Description

Technical area

[0001] The present invention relates to a cylinder guide mechanism for guiding a piston rod of a cylinder when the piston rod performs forward and backward operations relative to a tube, and to a cylinder equipped with a guide mechanism to which the guide mechanism is attached. State of the art

[0002] As is well known, a cylinder includes a piston that slides within a piston sliding hole formed in a tube, and a piston rod connected to the piston that slides integrally with the piston as the piston moves forward and backward. In this type of cylinder, for example, a predetermined workpiece is attached to the piston rod. In this case, the workpiece moves with the displacement of the piston rod. In other words, the cylinder serves as a transport means for transporting the workpiece.

[0003] However, in such a cylinder, a gap may develop due to size mismatches between the two elements of the piston and the piston slide hole. When a load (hereinafter referred to as a "lateral load") is applied in a direction perpendicular to the axial direction to a distal end of the piston rod protruding from the piston slide hole, another end portion of the piston rod, on the side thereof inserted into the piston slide hole, is displaced in a direction opposite to the direction of the lateral load. Specifically, when the piston rod and piston slide, skew is easily caused, and loosening or rattling of the piston rod is likely to occur.

[0004] It has therefore been widely practiced to provide a guide mechanism to prevent such loosening or rattling of the piston rod. As in Fig. For example, as shown in Figure 1 of JP 2006-105391 A, in a cylinder with a guide mechanism, a piston sliding hole and two guide holes are formed in a tube that clamp the piston sliding hole. A piston rod inserted into the piston sliding hole and guide rods inserted into the respective guide holes are each connected to a connecting plate. Therefore, the guide rods and the plate also perform displacement, following the forward and backward movements of the piston rod.

[0005] Because this configuration connects the piston rod to the guide rods via the connecting plate, chatter is unlikely to occur, even when lateral loads are applied. Furthermore, since it is surprisingly difficult for the piston rod to rotate, rotation-free precision is improved.

[0006] As in Fig. 3 of JP 09-303318 A, in the same manner as in JP 2006-105391 A, a cylinder with a guide mechanism is disclosed, which has a piston rod and two guide rods which are arranged so as to clamp the piston rod between them.

[0007] CN 1 01 191 508 A discloses a cylinder guide mechanism mounted on a cylinder. The cylinder has a piston rod movably received in a tube. The piston rod is coupled to the cylinder guide mechanism via a floating sleeve held by a holding portion. Furthermore, the cylinder guide mechanism comprises a guide mechanism with a guide element held by the holding portion. The guide element, in turn, holds a displaceable element that is designed to be displaceable relative to the guide element. The guide element is connected to the tube by pins. Summary of the invention

[0008] As discussed above, the cylinders with guide mechanisms described in JP 2006-105391 A and JP 09-303318 A are devices in which guide holes are formed in the tube, and the piston rod and guide rods inserted into the guide holes are connected by a connecting plate. Specifically, the cylinder mechanism and the guide mechanism share a single tube and are provided integrally with it.

[0009] Depending on the application environment, there may be cases where it is desirable to add a guide mechanism to an existing cylinder as a commercial retail product. However, when attaching a conventional guide mechanism to such a cylinder, a drilling process is required to form the guide holes in the tube. Accordingly, it is complicated to add a conventional guide mechanism to cylinders available as commercial retail products.

[0010] It is a main object of the present invention to propose a cylinder guide mechanism capable of being designed separately from a cylinder and easily attachable to such an existing cylinder.

[0011] It is another object of the present invention to provide a cylinder guide mechanism that does not require machining when the cylinder guide mechanism is mounted.

[0012] A still further object of the present invention is to provide a cylinder with a guide mechanism which is provided by attaching the above-mentioned cylinder guide mechanism to a cylinder.

[0013] According to one embodiment of the present invention, there is proposed a cylinder guide mechanism mounted on a cylinder in which a piston rod performs forward and backward operations relative to a tube, the cylinder mechanism comprising: a floating sleeve configured to perform forward and reverse operations following the forward and reverse operations of the piston rod; a holding portion configured to hold the floating sleeve; a guide mechanism having a guide member held by the holding portion and a displaceable member held on the guide member and configured to be displaced relative to the guide member; and a clamp designed to connect the movable element to the pipe.

[0014] When a cylinder with a guide mechanism is formed by attaching the cylinder guide mechanism to a cylinder, operations can be performed to fix the floating sleeve to the piston rod and to fix the sliding member to the tube via the clamp. Specifically, the cylinder guide mechanism can be installed without performing a drilling process for forming guide holes on an existing cylinder as a commercial retail product, and without the need for any other type of machining. In other words, the production of a so-called retrofit device is simplified.

[0015] Furthermore, as noted above, the assembly of the cylinder guide mechanism and the cylinder is simple. In other words, the cylinder guide mechanism is simply attached to the cylinder.

[0016] Furthermore, assuming that the floating sleeve can be attached to the piston rod and that the clamp can be connected to the tube, the cylinder guide mechanism can be mounted anywhere on the cylinder. Accordingly, by appropriately selecting the mounting position (and direction) of the guide mechanism, it is possible, for example, to prevent interference with the guide mechanism caused by a predetermined fastener to which the cylinder with the guide mechanism is attached. Thus, the above-described configuration achieves an advantage by increasing the degree of freedom for selecting the mounting position.

[0017] The holding section may be formed by a holding member that holds the floating sleeve, and by a workpiece conveying member that is supported by the guide member simultaneously with the holding member. In this case, a sleeve insertion hole into which the floating sleeve is inserted is formed in the workpiece conveying member, and a clearance of a certain size is formed between an inner wall of the sleeve insertion hole and a side wall of the floating sleeve.

[0018] In such a configuration, a first engagement portion may be formed on the floating sleeve, and a second engagement portion, which engages the first engagement portion, may be formed on the retaining member. A clearance of a certain size is formed between the first engagement portion and the second engagement portion.

[0019] The floating sleeve, the holding element, and the workpiece transfer element are manufactured with unavoidable tolerances. For example, if the center (axial center) of the sleeve insertion hole does not align with the center (axial center) of the piston rod, a condition known as axial center misalignment occurs. In such a case, if no clearance is provided between the inner wall of the sleeve insertion hole and the side wall of the floating sleeve, the floating sleeve cannot be easily attached to the piston rod because axial center misalignment occurs between the piston rod and the floating sleeve.

[0020] However, if a clearance is provided as described above, the floating sleeve can move relatively within the sleeve insertion hole within the specified clearance range. In other words, the floating sleeve is held in a so-called floating position. Since the axial center misalignment is absorbed, the floating sleeve can be easily attached to the piston rod.

[0021] The first engagement portion may be formed as a circumferential groove around the side wall of the floating sleeve. In this case, the second engagement portion may be an insert portion that is inserted into the circumferential groove.

[0022] As a preferred example of a clamp, an elbow-shaped element can also be offered in which two flat sections are connected via a bent section. As a detailed example, an L-shaped clamp with a substantially L-shaped configuration is proposed. In this case, one of the flat sections can abut against an end surface of the tube from which the piston rod protrudes, or it can abut against a rear surface on a side opposite the end surface, and a remaining one of the flat sections can be connected to the sliding element.

[0023] In particular, the one flat portion preferably abuts the above-mentioned rear surface. In this case, only the cylinder itself can be easily removed from the cylinder guide mechanism without removing the cylinder guide mechanism from the predetermined fastening member to which the cylinder guide mechanism is attached.

[0024] To attach the cylinder with a guide mechanism, in which the cylinder guide mechanism is attached to the cylinder, to a fastening element, the clamp can be positioned and fixed, for example, by a connecting element. For this purpose, a connecting element through-hole through which a connecting element is inserted is formed in the holding section. Furthermore, the connecting element through-hole has a larger diameter than the connecting element itself and a connecting element insertion hole formed in the tube.

[0025] In this case, even if the holding portion is positioned to cover the piston rod and the tube, the fastener can be inserted and passed through the fastener through-hole of the holding portion. As noted above, this is because the diameter of the fastener through-hole is larger than the fastener. Furthermore, the fastener, which has passed through the fastener through-hole, passes through the fastener insertion hole of the tube and the insertion hole of the bracket, and is also inserted into a predetermined insertion recess of the fastener. Accordingly, at the same time as the guide mechanism is mounted on the cylinder, the cylinder with the guide mechanism is positioned and fixed to the fastener.

[0026] In the manner described above, with such a configuration and by means of a simple operation, it is possible to attach the cylinder guide mechanism to the cylinder, and at the same time, the cylinder with guide mechanism can be attached to the fastening member.

[0027] A positioning element may also be provided in the connecting element through-hole, which is inserted therein and configured to position a workpiece. According to this feature, a workpiece can be easily positioned on the workpiece transport element. This allows the workpiece to be easily attached to the workpiece transport element, simplifying the transport of the workpiece.

[0028] In the case where the workpiece is transported by the cylinder with a guide mechanism, a workpiece support hole can be formed in the holding section. By supporting the workpiece on the holding section using the workpiece support hole, it is possible to transport the workpiece with the forward and backward movements of the piston rod and the floating sleeve.

[0029] According to another embodiment of the present invention, a cylinder with a guide mechanism is further provided, to which the cylinder guide mechanism having one of the above-described configurations is attached. Specifically, with such a cylinder with a guide mechanism, the above-described advantages and effects are achieved based on the above-described cylinder guide mechanism. Short description of the drawings Fig. 1 is a schematic perspective view of a cylinder with a guide mechanism according to a first embodiment of the present invention; Fig. 2 is an exploded perspective view of the cylinder with guide mechanism according to the first embodiment; Fig. 3 is a schematic side view of the cylinder with guide mechanism according to the first embodiment; Fig. 4 is a schematic exploded view from the side of the cylinder with guide mechanism according to the first embodiment; Fig. 5 is a schematic sectional view of the cylinder with guide mechanism according to the first embodiment; Fig. 6 is a schematic plan view of a holding plate (holding member) forming part of the guide mechanism; Fig. 7 is a schematic side view at a time when a piston rod, a floating sleeve, a holding portion, and guide grooves (guide member) of the cylinder with guide mechanism arrive at a top dead center position; Fig. 8 is a schematic perspective view of the cylinder with guide mechanism according to a second embodiment; Fig. 9 is a schematic side view of the cylinder with guide mechanism according to the second embodiment; Fig. 10 is a schematic perspective view of the cylinder with guide mechanism according to a third embodiment; Fig. 11 is a schematic side view of the cylinder with guide mechanism according to the third embodiment; Fig. 12 is a schematic perspective view of the cylinder with guide mechanism according to a fourth embodiment; Fig. 13 is a schematic exploded perspective view of the cylinder with guide mechanism according to the fourth embodiment; Fig. 14 is a schematic sectional view of the cylinder with guide mechanism according to the fourth embodiment; Fig. 15 is a schematic sectional view at a time when a holding portion is displaced in the cylinder with guide mechanism according to the fourth embodiment; Fig. 16 is a schematic perspective view of a flange member attachable to the cylinder with guide mechanism according to the fourth embodiment; Fig. 17 is a schematic side view showing a modified example in which a flange member is provided to the cylinder with guide mechanism according to the fourth embodiment; and Fig. Fig. 18 is a schematic side view showing a modified example in which the flange member is arranged at a position other than that shown in Fig. 17 is provided. Description of the embodiments

[0030] A detailed description of preferred embodiments of a cylinder guide mechanism according to the present invention, as well as a cylinder with a guide mechanism to which the cylinder guide mechanism is attached, is given below with reference to the accompanying drawings. In the following description, the cylinder guide mechanism is also referred to simply as a "guide mechanism."

[0031] The Fig. 1 to 3 are a schematic overall perspective view, a schematic exploded perspective view and a schematic overall side view of a cylinder 1 equipped with a guide mechanism according to a first embodiment, respectively, and Fig. 4 is a schematic exploded side view of a guide mechanism 12. The guide mechanism-equipped cylinder 10 is formed by attaching the guide mechanism 12 to a cylinder 14.

[0032] To begin with, I will describe cylinder 14 as it is in Fig. 5, such a cylinder 14 comprises a tube 16, a piston 20 inserted into a piston sliding hole 18 formed in the tube 16, and a piston rod 22 connected to the piston 20. An opening of the piston sliding hole 18 is closed by a collar 24, and a distal end of the piston rod 22 is exposed to the surroundings of the piston 16 via a through hole 26 formed substantially at the center of the collar 24. Hereinafter, the side on which the piston rod 22 is exposed is referred to as an upper side, and the opposite side is referred to as a lower side. Specifically, in the tube 16, for example,an end portion or end surface covered by the collar 24, being a side at which the distal end of the piston rod 22 is exposed, defines an upper end portion or end surface, while a closed surface forming a rear surface on a side opposite to the upper end surface defines a lower end surface.

[0033] The piston 20 includes a disc portion 28 with a substantially uniform diameter and a cylindrical protruding portion 30 having a smaller diameter and protruding outward from a lower end surface of the disc-shaped portion 28. When the piston 20 is at a bottom dead center, the lower end surface of the cylindrical protruding portion 30 rests on an inner wall of the lower end surface of the tube 16. A small gap (first chamber 32) is formed between the inner wall of the lower end surface of the tube 16 and the lower end surface of the disc-shaped portion 28.

[0034] On a side wall of the piston 20, an annular recess 34, which is diametrically recessed inward so as to encircle the side wall, is formed near the lower end surface of the disc-shaped portion 28. An annular piston seal 36, which forms a seal between the side wall of the piston 20 and the inner wall of the tube 16, is installed in the annular recess 34. Furthermore, a plurality of receiving holes 38, which are diametrically recessed inward, are formed near the upper end surface of the disc-shaped portion 28. Permanent magnets 39 are respectively received in the receiving holes 38.

[0035] A pin insertion hole 40 and a rod insertion hole 42, which is continuous with the pin insertion hole 40, are formed substantially in the center of the piston 20. The pin insertion hole 40 and the rod insertion hole extend along a thickness direction of the piston 20. The pin insertion hole 40 is formed up to a substantially middle portion in the thickness direction from the lower end surface of the piston 20, and the rod insertion hole 42 is formed from the substantially middle portion in the thickness direction to the upper end surface of the piston 20.

[0036] A lower end portion of the piston rod 22 is inserted into the rod insertion hole 42. A bolt hole (not shown) is formed in the lower end portion of the piston rod 22. By inserting a bolt (not shown) through the bolt insertion hole 40 and screwing it into the bolt hole, the piston rod 22 and the piston 20 are connected to each other.

[0037] As noted above, the upper end portion of the piston rod 22 passes through the through-hole 26 of the collar 24. A sleeve 43 and a rod seal 44 are disposed between an inner wall of the through-hole 26 and a side wall of the piston rod 22. The piston rod 22 is displaced while sliding relative to the sleeve 43 and the rod seal 44. Furthermore, the collar 22 is locked into engagement with the tube 16 by an annular locking member 46. This positions and fixes the collar 24 at a position near the opening of the piston sliding hole 18. A seal 47, which seals a gap between the side wall of the collar 24 and the inner wall of the piston sliding hole 18, is attached to the side wall of the collar 24.

[0038] A bottomed connecting hole 48 is formed in the upper end portion of the piston rod 22. Threads (not shown) are formed on an inner peripheral wall of the connecting hole 48. A lower end portion of a floating sleeve 50 (see Fig. 1 to 4), which forms part of the guide mechanism 12, is screwed to the thread.

[0039] The piston sliding opening 18 is divided into a first chamber 32 and a second chamber 52, with the disc-shaped portion 28 of the piston 20 forming a boundary between the chambers. Specifically, the first chamber 32 is formed between an inner wall of the lower end surface of the tube 16 and the lower end surface of the disc-shaped portion 28, and the second chamber 52 is formed between the upper end surface of the disc-shaped portion 28 and a lower end surface of the collar 24. Movement of a working fluid from the first chamber 32 to the second chamber 52 or in a direction opposite thereto is prevented by the piston seal 36. Furthermore, movement of the working fluid from the second chamber 52 to the atmosphere or in a direction opposite thereto is prevented by the piston seal 44.

[0040] A first port 54 communicating with the first chamber 32 and a second port 56 communicating with the second chamber 52 are formed in the tube 16. A working fluid (e.g., air) is supplied to the first chamber 32 and the second chamber 52 through the first port 54 and the second port 56, or the working fluid is discharged from the first chamber 32 and the second chamber 52.

[0041] As in the Fig. As shown in FIGS. 1 to 3, four tie rod insertion holes 58 (connector insertion openings) are formed in a continuous manner along a thickness direction (i.e., a longitudinal direction from the lower end portion to the upper end portion) in the tube 16. Elongated tie rods 60 serving as connecting members are inserted through the respective tie rod insertion holes 58. The respective tie rods 60 are provided with threaded holes 64 (see FIG. Fig. 3) a predetermined fastening element 62 (predetermined element) provided on the lower end side of the tube 16, whereby the cylinder 10 with guide mechanism is positioned and fixed to the fastening element 62. At the same time, the tube 16 is connected to the fastening element 62.

[0042] Next, the guide mechanism 12 will be described. The guide mechanism 12 includes the floating sleeve 50, a holding portion 70 that holds the floating sleeve 50, and a linear guide 72 (guide mechanism) held on the holding portion 70.

[0043] As in Fig. As shown in Fig. 4, a lower end portion of the floating sleeve 50 is formed as a small-diameter threaded portion. The threaded portion is inserted into the connecting hole 48 formed in the upper end portion of the piston rod 22 and screwed with the thread formed on the inner peripheral wall of the connecting hole 48. Accordingly, when the floating sleeve 50 is connected to the piston rod 22, the piston rod 22 and the floating sleeve 50 extend coaxially along the same axis.

[0044] At a large-diameter upper end portion of the floating sleeve 50, an annular groove 74 (circumferential groove) is provided, which is diametrically recessed inward and encircles the side wall. The annular groove 74 acts as a first engagement portion for holding the floating sleeve 50 to the holding portion 70.

[0045] In addition, a screw hole 76 with a bottom for inserting a screwdriver or wrench is formed in a recessed manner on the upper end surface of the floating sleeve 50.

[0046] In this case, the holding section 70 comprises a holding plate (holding element) 78 and an L-shaped plate 80 (workpiece transport element) which holds the holding plate 78. In these features, the holding plate 78 shows as in Fig. 6, a substantially Y-shape is formed. Therefore, a U-shaped groove 82 is formed in its distal end portion, which is forked. A portion at an upper end portion of the floating sleeve 50, in which the annular groove 74 is formed, is inserted into the U-shaped groove 82.

[0047] A width dimension W1 of an opening of the U-shaped groove 82 is selected to be smaller than a diameter of the upper end portion of the floating sleeve 50. Therefore, a side wall of the lower end surface of the annular groove 74 of the floating sleeve 50 abuts against the retaining plate 78, and as a result, the floating sleeve 50 is locked therein. Accordingly, the floating sleeve 50 is prevented from coming out of the U-shaped groove 82. Specifically, a region near the U-shaped groove 82 serves as an insertion portion (second engagement portion) for engaging with the annular groove 74 by inserting into the annular groove 74.

[0048] In this case, the width dimension W1 of the U-shaped groove 82 is slightly larger than the diameter D1 of a portion of the floating sleeve 50 corresponding to the bottom wall of the annular groove 74. Therefore, a certain clearance 84 with a predetermined distance is formed between the bottom wall of the annular groove 74 (first engagement portion) and the inner wall of the U-shaped groove 82 (second engagement portion).

[0049] The holding plate 78 is connected to the L-shaped plate 80, for example by welding (see Fig. 1 to 3) and thereby held on the L-shaped plate 80. As a result, the floating sleeve 50 is held on the L-shaped plate 80 by the holding plate 78. In this case, moreover, the fork-shaped distal end portion of the holding plate 78 is oriented toward the first terminal 54 and the second terminal 56, and its plate-shaped rear end portion also faces the linear guide 72.

[0050] On a flat roof wall section 85 of the L-shaped plate 80 there is a sleeve insertion opening 86 (cf. Fig. 1 and Fig. 2) formed in a thickness-through manner. The upper end portion of the floating sleeve 50 is inserted into the sleeve insertion opening 86. The upper end surface of the floating sleeve 50 and the upper end surface of the L-shaped plate 80 are substantially coplanar.

[0051] As in the Fig. 1 and Fig. 3, the diameter D2 of the sleeve insertion hole 86 is slightly larger than the diameter D3 of the upper end surface of the floating sleeve 50. Therefore, a certain clearance 88 having a fixed distance is formed between the inner wall of the sleeve insertion hole 86 and the side wall of the upper end surface of the floating sleeve 50.

[0052] As in the Fig. 1 and Fig. As shown in Fig. 2, four tie rod through-holes 90 (connector through-holes) through which the tie rods 60 pass, and two workpiece holding holes 91 are formed in a thickness-through manner in the roof wall portion 85. The four tie rod through-holes 90 are arranged at positions corresponding to the vertices of a square and are formed to face the tie rod insertion holes 58 formed in the tube 16. On the other hand, the workpiece holding holes 91 are formed closer to the sleeve insertion hole 86 than the rod through-holes 90 and at positions sandwiching the sleeve insertion hole 86.

[0053] The workpiece holding holes 91 are members for fastening a predetermined workpiece (not shown). Specifically, for example, in the case where threaded engagement holes are formed in the workpiece, bolts can be inserted from the lower end surface side of the roof wall portion 85 of the L-shaped plate 80 through the workpiece holding holes 91 and screwed into the threaded engagement holes. As shown in Fig. 6, the holding plate 78 naturally has a shape and size that does not interfere with the workpiece holding holes 91. Otherwise, through holes 92 connected to the workpiece holding holes 91 may be formed in the holding plate 78.

[0054] Instead of holding the workpiece with bolts, the workpiece can also be held by stepped pins inserted through the workpiece holding holes 91.

[0055] A guide member 96, which is formed by the linear guide 72 as a guide mechanism, is welded, for example, to a downwardly hanging wall portion 94 that is bent and hangs from the roof wall portion 85 of the L-shaped plate 80. This holds the linear guide 72 to the support portion 70. Since the support plate 78 is held to the L-shaped plate 80 as described above, the support plate 78 is also indirectly held to the guide member 96. Specifically, the support portion 70 is held by the guide member 96.

[0056] In this case, the linear guide 72 is a so-called circulating ball linear guide. Specifically, a slider 98, which serves as a sliding element, is displaced relative to the guide element 96 by a plurality of balls 100 circulating in guide grooves 101 formed in the guide element 96. It should be understood that the slider 98 moves along the guide grooves 101.

[0057] An L-shaped bracket 102 serving as a bracket is attached to the slider 98 and the tube 16. Specifically, the L-shaped bracket 102 includes a roof wall portion 104 (flat portion) and a downwardly hanging wall portion 106 (flat portion) that is substantially curved and hangs downward from the roof wall portion 104. The L-shaped bracket 102 is an elbow-shaped member in which an intersection angle of the roof wall portion 104 and the downwardly hanging wall portion 106 forms an angle of approximately 90°. In other words, the roof wall portion 104 and the downwardly hanging wall portion 106 are connected via a curved portion.

[0058] Of these elements, the downwardly hanging wall portion 106 is attached (held) to the slider 98 by bolts 108. On the other hand, four tie rod locking holes 110 are formed in the roof wall portion 104, and the pipe 16 is attached (held) to the roof wall portion 104 by the tie rods 60, the heads of which are locked in the respective tie rod locking holes 110.

[0059] The cylinder 10 with a guide mechanism according to the first embodiment is constructed substantially as described above. Next, the operations and advantages regarding the attachment process of the guide mechanism 12 to the cylinder 14 and the movement actions of the cylinder 14 will be described.

[0060] In order to attach the guide mechanism 12 to the cylinder 14 and at the same time to attach the cylinder 10 with guide mechanism to the predetermined fastening element 62 (cf. Fig. 3), first, the threaded portion of the floating sleeve 50, which forms part of the preassembled guide mechanism 12, is inserted into the connecting hole 48 of the piston rod 22. Subsequently, the floating sleeve 50 is rotated by a screwdriver, wrench, or the like inserted into the screw hole 76 of the floating sleeve 50. Accordingly, the threaded portion of the floating sleeve 50 is screwed to the thread of the connecting hole 48.

[0061] Next, the lower end surface of the tube 16 is brought into abutment against a predetermined position of the fastening member 62. At this time, the positions of the tie rod insertion holes 58 coincide with the positions of the threaded holes 64 formed in the fastening member 62. Specifically, the tie rod insertion holes 58 are arranged to merge into the threaded holes 64.

[0062] In such a state, the lower end surface of the roof wall portion 104 of the L-shaped bracket 102 of the guide mechanism 12 is brought into abutment against the upper end surface of the pipe 16, so that the tie rod locking holes 110 are adjacent to the tie rod insertion holes 58 of the pipe 16. Furthermore, the threaded portions of the tie rods 60 are passed through the tie rod through holes 90 of the L-shaped plate 80, the tie rod locking holes 110, and the tie rod insertion holes 58 of the pipe 16, and are screwed into the threaded holes 64. The diameters of the head portions of the tie rods 60 are smaller than the diameters of the tie rod through holes 90, so that the tie rods 60 can easily pass through the tie rod through holes 90.

[0063] Furthermore, because the diameters of the head portions of the tie rods 60 are larger than the diameters of the tie rod locking holes 110, the head portions of the tie rods 60 are locked at positions near the openings of the tie rod locking holes 110. Accordingly, the tie rods 60 connect the L-shaped bracket 102 to the pipe 16 and simultaneously connect the pipe 16 to the fastener 62. Thanks to the above features, along with the attachment of the guide mechanism 12 to the cylinder 14, the cylinder 14 is positioned and fixed to the fastener 62.

[0064] In the manner described above, according to the first embodiment, the floating sleeve 50 is attached (connected) to the piston rod 22 in such a manner that the floating sleeve 50 extends substantially coaxially with the piston rod 22, and the slider 98 is attached to the tube 16 through the L-shaped bracket 102. Therefore, the manufacture of a so-called retrofit device attached to an existing cylinder 14 is facilitated.

[0065] Simultaneously with the attachment of the guide mechanism 12 to the cylinder 14, the cylinder 14 is also positioned and fixed to a predetermined fixing member 62. Specifically, the assembly of the cylinder 10 with the guide mechanism and the attachment of the cylinder 10 with the guide mechanism to the fixing member 62 can be performed efficiently. Furthermore, both the assembly and fixing processes are simple, and there is no particular need for machining in either case.

[0066] When manufacturing the floating sleeve 50, the retaining plate 78, and the L-shaped plate 80, tolerances are inevitably generated in the dimensions of the respective fasteners 62. Therefore, in the first embodiment, the clearance 84 is formed between the inner wall of the U-shaped groove 82 of the retaining plate 78 and the bottom wall of the annular groove 74 of the floating sleeve 50. At the same time, the clearance 88 is formed between the inner wall of the sleeve insertion opening 86 of the L-shaped plate 80 and the side wall of an upper end portion of the floating sleeve 50.

[0067] If such clearances 84, 88 were not provided, a misalignment of the axial centers between the floating sleeve 50 and the piston rod would occur if the center axes of the piston sliding hole 18, the U-shaped groove 82, and the sleeve insertion hole 86 did not exactly align. In such a case, inserting the lower end portion of the floating sleeve 50 into the connecting hole 48 of the piston rod 22 and screwing the floating sleeve could not be easily performed.

[0068] In contrast, according to the present embodiment, since the clearances 84, 88 are provided, the floating sleeve 50 can be displaced relative to the holding portion 70 within the range of the clearance, that is, the clearances 84, 88, that are provided. Specifically, while the floating sleeve 50 is held in a state supported by the holding plate 78 and thus by the holding portion 70, the floating sleeve 50 can be connected to the piston rod 22 in such a manner that its center axis coincides with the center axis of the piston rod 22.

[0069] By providing the clearances 84, 88 in the manner described above, when an axial misalignment occurs between the piston sliding hole 18, the U-shaped groove 82 and the sleeve insertion hole 86, this axial misalignment is absorbed and the floating sleeve 50 can be attached to the piston rod 22.

[0070] In addition, a workpiece (not shown) is fixed to the L-shaped plate 80 via bolts or the like passing through the workpiece holding holes 91. Accordingly, the workpiece is held on the cylinder 10 with a guide mechanism.

[0071] The cylinder 10 with guide mechanism is operated in the following manner. When the piston rod 22 and the floating sleeve 50 are at their bottom dead center positions, a working fluid (e.g., air) is discharged from the Fig. 5 into the first chamber 32. The piston 20 receives a pressure force from the working fluid supplied to the first chamber 32. This causes the piston 20 and piston rod 22 to rise. At this time, the working fluid held in the second chamber 52 is discharged via the second port 56.

[0072] As the piston rod 22 rises, the floating sleeve 50 also rises. Furthermore, since the floating sleeve 50 is held by the support plate 78 and the L-shaped plate 80 supporting the support plate 78 is also supported by the guide member 96, the support portion 70 and the guide member 96 rise, following the rise of the floating sleeve 50. At this time, since the balls 100 circulate in the guide grooves 101, the slider 98 is held at its original position. Accordingly, the slider 98 descends relative to the guide member 96.

[0073] Finally, the piston rod 22, the floating sleeve 50, the holding section 70 and the guide element 96 arrive at their top dead center positions, as shown in Fig. 7. This transports the workpiece by the stroke of the floating sleeve 50 and the piston rod 22.

[0074] Since the guide element 96 is in a straight line (in the direction Z1) in Fig. 3 rises upward, the floating sleeve 50, which is held on the guide member 96 via the holding portion 70, also rises upward in a straight line without any inclination. Therefore, the piston rod 22 and the piston 20 also rise upward in a straight line. Accordingly, loosening or rattling due to an inclination of the piston rod 22 and the piston 20 is avoided.

[0075] In addition, since the tube 16 is protected by the guide member 96, etc., even if the above-mentioned lateral loads act on the cylinder 10 with guide mechanism, these lateral loads are unlikely to be transmitted to the piston rod 22 and the guide sleeve 50. As a result, loosening or rattling is more effectively prevented.

[0076] Furthermore, since the holding portion 70 is connected to the guide member 96, rotation of the floating sleeve 50 held by the holding portion 70 and rotation of the piston rod 22 are unlikely to occur. Therefore, the non-rotational precision is also improved.

[0077] When the piston rod 22 and the floating sleeve 50, which are arranged at their top dead center positions, return to their bottom dead center positions, a working fluid (e.g., air) is supplied from the second port 56 to the second chamber 52 (see FIG. Fig. 5). The piston 20 receives a pressure force from the working fluid supplied to the second chamber 52 and descends. The working fluid held in the first chamber 32 is discharged via the first port 54.

[0078] Following the descent of the piston 20, the piston rod 22 and the floating sleeve 50 also descend. In particular, both the holding portion 70 and the guide element 96 descend. Since the balls 100 circulate in the guide grooves 101, the slider 98 is held in its original position. Accordingly, the slider 98 rises relative to the guide element 96.

[0079] When the working fluid is supplied to the interior of the tube 16 in the manner described above and the forward and backward movements of the piston rod 22 occur, the floating sleeve 50 and the guide member 96 also perform forward and backward movements in the same directions and following the movements. Although maintaining the same position, the slider 98 of the linear guide 72 is displaced relative to the guide member 96.

[0080] Finally, the piston rod 22, the floating sleeve 50, the holding section 70 and the guide element 96 return to the positions shown in Fig. 3 and reach their bottom dead center positions. When the floating sleeve 50 and the piston rod 22 return from the top dead center positions to their bottom dead center positions, a workpiece other than the one described above can be transported.

[0081] In addition, after returning from the top dead center position to the bottom dead center position, the floating sleeve 50, the piston rod 22 and the piston 20 descend in a straight line because the guide member 96 descends in a straight line (in the direction of the arrow Z2) in Fig. 7. Accordingly, loosening or rattling is also avoided in this case by an inclined position of the piston rod 22 and the piston 20. It goes without saying that the rotation-free precision is also improved.

[0082] Although in the first embodiment, the lower end surface of the roof wall portion 104 of the L-shaped bracket 102 is brought into abutment against the upper end surface of the pipe 16 and the L-shaped bracket 102 and the pipe 16 are connected to each other by the tie rods 60, the flat portion may also be brought into abutment against a lower end surface of the pipe 16. Such a configuration will be described as a second embodiment. The structural elements that are the same as those shown in the Fig. 1 to 7 are provided with substantially the same reference numerals and the detailed description of these features is omitted here.

[0083] Fig. Fig. 8 is a schematic perspective overall view of a cylinder 120 with guide mechanism according to a second embodiment, and Fig. 9 is a schematic overall side view of the cylinder. In a guide mechanism 122 of the guide mechanism cylinder 120, an L-shaped bracket 124 includes a bottom wall portion 126 (flat portion) and a vertical wall portion 127 (flat portion) that rises upward in a substantially vertical direction from the bottom wall portion 126. Of these elements, the vertical wall portion 127 is attached to the slider 98 via bolts 108 in the same manner as the downwardly hanging wall portion 106 of the L-shaped bracket 102 in the guide mechanism cylinder 10 according to the first embodiment.

[0084] Four tie rod insertion holes 128 are formed in the bottom wall portion 126 to penetrate in the thickness direction (vertical direction). Furthermore, two tabs 130 are formed in the bottom wall portion, which protrude symmetrically to the left and right sides. Bolt insertion holes 132 are formed to penetrate the respective tabs 130.

[0085] In this case, in the fastening member 62, in addition to the threaded holes 64 into which the tie rods 60 are screwed, other threaded holes 136 are formed into which bolts 134 are screwed. The bottom wall portion 126 wound around the lower end surface of the pipe 16 is positioned and fixed in a state of being received between the fastening member 62 and the pipe 16 by screwing the tie rods 60 into the threaded holes 64 and by screwing the threaded portions of the bolts 134, which have been passed through the bolt insertion holes 132, into the threaded holes 136.

[0086] In the second embodiment, the guide mechanism 122 is further attached to the cylinder 14 by passing the threaded portions of the tie rods 60, which have been passed through the tie rod through holes 90 of the L-shaped plate 80, through the tie rod insertion holes 58 of the tube 16 and the tie rod insertion holes 128 of the L-shaped bracket 124, and then screwing them into the threaded holes 64. Furthermore, the cylinder 120 with the guide mechanism is attached to the fastening member 62 by screwing in the tie rods 60 and the bolts 134.

[0087] The diameters of the head portions of the tie rods 60 are larger than the diameter of the tie rod insertion holes 58 of the tube 16. Therefore, the tie rods 60 are blocked by the tube 16.

[0088] In the event that any maintenance is to be performed on the cylinder 14, if it becomes necessary to remove the cylinder 14, a screwdriver, wrench, or the like can be inserted from the tie rod insertion holes 90 of the L-shaped plate 80, and the tie rods 60 can be released by unscrewing them. The tie rods 60 can be pulled out by passing them through the tie rod through holes 90, and the tie rods 60 can remain inserted through the tie rod insertion holes 58 of the tube 16.

[0089] Furthermore, a screwdriver, wrench, or the like is inserted into the screw hole 76 of the floating sleeve 50, and the floating sleeve 50 is detached from the piston rod 22 by unscrewing the floating sleeve 50. In the manner described above, the cylinder 14 is released from the restraint by the guide mechanism 122.

[0090] Subsequently, the cylinder 14 is removed from between the bottom wall portion 126 of the L-shaped bracket 124 and the top wall portion 85 of the L-shaped plate 80, whereupon the cylinder 14 is exposed to the surroundings of the guide mechanism 122. In other words, the cylinder 14 is removed from the guide mechanism 122.

[0091] Subsequently, maintenance or the like is performed on the cylinder 14. Assuming that the tie rods 60 are inserted between the bottom wall portion 126 of the L-shaped bracket 124 and the top wall portion 85 of the L-shaped plate 80 and then screwed into the threaded holes 64, the cylinder 14 can be reattached to the guide mechanism 122. During the maintenance period, another prepared cylinder 14 can also be attached to the guide mechanism 122, and the workpiece transfer can be performed with it.

[0092] During the time the cylinder 14 is removed and reattached in the manner described above, the guide mechanism 122 remains attached to the fastener 62 by the bolts 134 that positioned and fixed the L-shaped bracket 124 by screwing it into the threaded holes 136 of the fastener 62. In other words, when the cylinder 14 is removed from the guide mechanism 122 and when it is reattached to the guide mechanism 122, there is no particular need to remove the guide mechanism 122 from the fastener 62. Therefore, both removal and reattachment can be performed easily.

[0093] The operation and other advantageous effects of the cylinder 120 with guide mechanism according to the second embodiment are the same as those of the cylinder 10 with guide mechanism according to the first embodiment, so the detailed description of these features is omitted here.

[0094] By using two L-shaped clamps, one of the L-shaped clamps can be configured to abut the lower end surface of the tube 16, while the remaining L-shaped clamp can be configured to abut the upper end surface of the tube 16. Such a configuration will be described as a third embodiment. The structural elements that are the same as those shown in the Fig. 1 to 9 are generally provided with the same reference numerals and the detailed description of these features will now be omitted.

[0095] Fig. 10 is a schematic perspective overall view of a cylinder 140 with a guide mechanism according to a third embodiment, and Fig. Figure 11 is a schematic side view of the cylinder. A guide mechanism 142 of the cylinder 140 with guide mechanism includes a first L-shaped bracket 144 and a second L-shaped bracket 146.

[0096] The first L-shaped bracket 144 is constructed in substantially the same shape as the L-shaped bracket 124 and includes a first bottom wall portion 148 (flat portion) and a first vertical wall portion 150 (flat portion) that is long and extends upward in a substantially vertical direction from the first bottom wall portion 148. Of this feature, four tie rod insertion holes 128 are formed in the first bottom wall portion 148 so as to penetrate in the thickness direction (vertical direction). Furthermore, two extended portions 152 are formed in the first bottom wall portion 148, which protrude symmetrically outwardly on the left / right sides. Bolt insertion holes 154 are formed so as to penetrate through the respective extended portions 152.

[0097] The other first vertical wall portion 150 is attached to the slider 98 via bolts 108. Furthermore, the second L-shaped bracket 146 is positioned and fixed to the first vertical wall portion 150. Specifically, the second L-shaped bracket 146 includes a second bottom wall portion 156 (flat portion) and a second vertical wall portion 158 (flat portion) that is short and extends upward in a substantially vertical direction from the second bottom wall portion 156. Insertion holes are formed to penetrate the first vertical wall portion 150 and the second vertical wall portion 158 so that when the second vertical wall portion 158 abuts against the first vertical wall portion 150, the through holes overlap each other. Bolts 160 are passed through the insertion holes. Furthermore, nuts 162 are screwed to the bolt 160.Accordingly, the first L-shaped bracket 144 and the second L-shaped bracket 146 are connected.

[0098] In the same manner as the top wall portion 104 of the L-shaped bracket 102 in the first embodiment, the second bottom wall portion 156 covers the upper end surface of the tube 16. Four tie rod locking holes 110 are formed in the second bottom wall portion 156.

[0099] In the third embodiment, the threaded portions of the tie rods 60, which pass through the tie rod through holes 90 of the L-shaped plate 80, are further passed through the tie rod locking holes 110 formed in the second bottom wall portion 156 of the second L-shaped bracket 146, the tie rod insertion holes 58 formed in the tube 16, and the tie rod insertion holes 128 formed in the first bottom wall portion 148 of the first L-shaped bracket 144, and then screwed into the threaded holes 64 formed in the fastening member 62. Accordingly, the guide mechanism 142 is mounted to the cylinder 14, and the cylinder 140 with the guide mechanism is also attached to the fastening member 62.

[0100] The diameters of the head portions of the tie rods 60 are larger than the diameters of the tie rod blocking holes 110. Therefore, the tie rods 60 are blocked by the second bottom wall portion 156 of the second L-shaped bracket 146.

[0101] Here, threaded holes 166 are formed in the fastening member 62 for screwing in bolts 164 passed through the bolt insertion hole 154 of the first bottom wall portion 148. The first bottom wall portion 148, which is wound around the lower end surface of the pipe 16, is positioned and fixed in a state in which it is interposed between the fastening member 62 and the pipe 16 by screwing the tie rods 60 into the threaded holes 64 and by screwing threaded portions of the bolts 164, which are passed through the bolt insertion holes 154, into the threaded holes 166.

[0102] Furthermore, in the third embodiment, a holding plate 168 which holds the floating sleeve is formed by a small flat plate-shaped member having a U-shaped groove 82 formed therein.

[0103] In the event that any type of maintenance needs to be performed on the cylinder 14, if it becomes necessary to remove the cylinder 14, a screwdriver, wrench, or the like can be inserted from the tie rod through holes 90 of the L-shaped plate 80 and the tie rods 60 can be unscrewed. The tie rods 60 can be pulled out by passing through the tie rod through holes 90, and the tie rods 60 can remain inserted into the tie rod locking holes 110 of the second L-shaped bracket 146.

[0104] Furthermore, a screwdriver, wrench, or the like is inserted into the screw hole 76 of the floating sleeve 50, and the floating sleeve 50 is detached from the piston rod 22 by unscrewing the floating sleeve 50. In the manner described above, the cylinder 14 is released from the restraint by the guide mechanism 142.

[0105] Subsequently, the cylinder 14 is removed from its position between the first bottom wall portion 148 of the first L-shaped bracket 144 and the second bottom wall portion 156 of the second L-shaped bracket 146, whereupon the cylinder 14 is exposed to the surroundings of the guide mechanism 142. In other words, the cylinder 14 is removed from the guide mechanism 142.

[0106] Assuming that the cylinder 14 on which maintenance work and the like have been performed is subsequently inserted between the first bottom wall portion 148 of the first L-shaped bracket 144 and the second bottom wall portion 156 of the second L-shaped bracket 146, and further, the tie rods 60 are screwed into the threaded holes 64, the cylinder 14 can be reattached to the guide mechanism 142. During the maintenance operation, another prepared cylinder 14 can also be attached to the guide mechanism 142, and the transfer of workpieces can be performed thereby.

[0107] During the time the cylinder 14 is removed and then reattached in the manner described above, the guide mechanism 142 remains attached to the fastener 62 by the bolts 164 that positioned and fixed the first L-shaped bracket 144 by screwing it into the threaded holes 166 of the fastener 62. In other words, when the cylinder 14 is removed from the guide mechanism 142, and also when it is reattached to the guide mechanism 142, there is no particular need to remove the guide mechanism 142 from the fastener 62. Therefore, both the removal and reattachment can be easily performed.

[0108] The operations and other advantageous effects of the guide mechanism cylinder 140 according to the third embodiment are the same as those of the guide mechanism cylinder 10 according to the first embodiment and the guide mechanism cylinder 120 according to the second embodiment. Therefore, a detailed description of these features will be omitted here.

[0109] The fastener through-holes represented by the tie rod through-holes 90 may also contain positioning elements that are inserted therein and serve to position the workpiece. Such a configuration is described as a fourth embodiment. Structural elements that are the same as those used in the Fig. 1 to 11 are generally referred to by the same names and a detailed description of these features is omitted.

[0110] The Fig. 12 to 14 are a schematic perspective view, a schematic exploded perspective view, and a schematic cross-sectional view, respectively, of a cylinder 180 with a guide mechanism according to a fourth embodiment. The cylinder 180 with a guide mechanism is formed by attaching a guide mechanism 182 to a cylinder 14.

[0111] In this case, a flat plate 184 and an L-shaped plate 186 are provided on the side of a lower end surface of the tube 16. Tie rod threaded holes 188, which overlap the tie rod insertion holes 58 of the tube 16, and first tie rod through holes 190 are formed in the flat plate 184 and the L-shaped plate 186. As discussed below, the tie rods 60, which have passed through the first tie rod through holes 190, are screwed into the tie rod threaded holes 188. Accordingly, the tube 16 is connected to the flat plate 184, and the L-shaped plate 186 is clamped and gripped between the tube 16 and the flat plate 184. Specifically, in the fourth embodiment, the flat plate 184 becomes the "predetermined member."

[0112] Through holes 192, 194 are formed between the adjacent tie rod threaded holes 188, 188 and between the first tie rod through holes 190, 190, respectively. The tie rod threaded holes 188 and through holes 192 penetrate the flat plate 184 in the thickness direction, and the first tie rod through holes 190 and through holes 194 penetrate the L-shaped plate 186 in the thickness direction. The positions of the tie rod threaded holes 188 correspond to the positions of the first tie rod through holes 190, and the positions of the through holes 192 correspond to the through holes 194.

[0113] In addition, a bolt receiving opening 198 into which a thread is cut is formed in a vertical wall portion 196 of the L-shaped plate 186.

[0114] On the other hand, the guide mechanism 182 includes a floating sleeve 200, a holding portion 202 which holds the floating sleeve 200, and a linear guide 204 (guide mechanism) which guides the floating sleeve 200 over the holding portion 202.

[0115] The floating sleeve 200 includes a shaft portion 206, a blocking portion 208, and a head portion 210, whose diameters increase in this order. The shaft portion 206 is inserted into the connecting hole 48 formed in the upper end portion of the piston rod 22, and a threaded portion formed on its side wall is screwed into a thread formed in the connecting hole 48.

[0116] An annular projection 212 is formed on the shaft portion 206 at its upper portion near the locking portion, projecting outward in a diametrical direction. The annular projection 212 has a smaller diameter than the locking portion 208. Furthermore, a bottomed screw hole 214 for inserting a screwdriver, a wrench, or the like is formed in a recessed manner on the upper end surface of the head portion 210, which is connected to an upper surface of the locking portion 208.

[0117] In the fourth embodiment, the holding portion 202 includes an L-shaped arm member 216 (workpiece transporting member) for transporting workpieces and a retaining ring 218 (holding member) for holding the floating sleeve 200 on the L-shaped arm member 216. Here, the shaft portion 202 of the floating sleeve 200 is passed through the retaining ring 218.

[0118] The inner diameter of the retaining ring 218 is selected to be substantially equivalent to the maximum diameter of the annular projection 212. On the other hand, the thickness of the retaining ring 218 is greater than the thickness of the annular projection 212. Accordingly, the annular projection 212 only abuts a portion of the inner wall of the retaining ring 218. In other words, a large portion of the inner wall of the retaining ring 218 remains spaced from the shaft portion 206.

[0119] A sleeve insertion hole 222 is formed on a flat roof wall portion 220 of the L-shaped arm member 216 so as to penetrate in the thickness direction. An annular stepped portion 224 is formed in the sleeve insertion hole 222, so that the sleeve insertion hole 222 consists of a small-diameter hole 226 and a large-diameter hole 228. The small-diameter hole 226 has a larger diameter than the shaft portion 206 and the blocking portion 208, but has a smaller diameter than the head portion 210. Furthermore, the large-diameter hole 228 has a larger diameter than the head portion 210.

[0120] The shaft portion 206 and the blocking portion 208 of the floating sleeve 200 pass through the small-diameter opening 226. As noted above, the shaft portion 206 is also screwed into the connecting hole 48. This screw connection holds the retaining ring 218 between the upper surface of the piston rod 22 and the bottom surface of the blocking portion 208. This prevents the floating sleeve 200 from being pulled out of the sleeve insertion hole 222. Specifically, the floating sleeve 200 is held to the L-shaped arm member 216 by the retaining ring 218.

[0121] The side wall of the blocking portion 208 is spaced from the inner wall of the small-diameter opening 226. Furthermore, the head portion 210 of the floating sleeve 200 is spaced from both the inner wall of the large-diameter opening 228 and the annular stepped portion 224. Specifically, a predetermined clearance is formed between the floating sleeve 200 and the L-shaped arm member 216.

[0122] Therefore, the floating sleeve 200 is not obstructed by the L-shaped arm member 216. In this case, too, a floating state is finally achieved in which the floating sleeve 200 can move relatively within the sleeve insertion opening 222 with a certain amount of play.

[0123] Furthermore, the upper end surface of the head portion 210 is placed in a state where it is received in the sleeve insertion opening 222. In other words, the upper end surface of the head portion 210 is positioned lower than the upper end surface of the L-shaped arm portion 216.

[0124] In addition, four second tie rod through-holes 230 (connector through-holes) through which the tie rods 60 pass, and four workpiece holding holes 232 are formed in the roof wall portion 220 in a thickness-through manner. The four second tie rod through-holes 230 are positioned at locations corresponding to the vertices of a square and are formed to face the tie rod insertion holes 58 formed in the tube 16. On the other hand, the workpiece holding holes 223 are formed closer to the sleeve insertion hole 222 than the second tie rod through-holes 230 and at positions between the respective adjacent second tie rod through-holes 230, 230.

[0125] Stepped pins 234 (positioning elements) are inserted into the second tie rod through-holes 230. Specifically, each of the stepped pins 234 is formed by linearly connecting a fastening insert 236 having a cylindrical or columnar shape, a large-diameter stopper 238 whose diameter is larger than the second tie rod through-holes 230, and a positioning insert 240 for positioning the workpiece. The fastening inserts 236 are inserted into the second tie rod through-holes 230, and the exposed positioning inserts 240 are inserted into predetermined positioning holes formed in the workpiece.

[0126] On the other hand, the workpiece holding holes 232 serve as members for attaching the workpiece to the L-shaped arm member 216. For example, in the case where threaded engagement holes are formed in the workpiece, bolts can be inserted through the workpiece holding holes 232 from the lower end surface side of the roof wall portion 220 of the L-shaped arm member 216 and screwed into the threaded holes. Otherwise, in the same manner as the second tie rod through holes 230, the stepped pins can be inserted, and the workpiece can be held by the stepped pins.

[0127] A bottomed cutout 244, shaped in the form of a bisected elongated hole, is formed in a downwardly hanging wall portion 242, which is bent and hangs downward from the roof wall portion 220 of the L-shaped arm portion 216. Furthermore, threaded holes 246 are formed in the downwardly hanging wall portion 242, and a guide member 250, which forms the linear guide 204 as a guide mechanism, is connected to the downwardly hanging wall portion 242 via screws 248 screwed into the threaded holes 244. By means of this connection, the guide member 250 is held on the L-shaped arm member 216. The guide member 250 is arranged so that the bottomed cutout 244 remains exposed.

[0128] Screw insertion holes 252 through which the screws 248 are passed, and a rivet hole 254 are formed in the guide member 250. A shaft portion of a rivet passed through the rivet hole 254 is crushed, thereby preventing the rivet 256 from being pulled out of the rivet hole 254. The crushed shaft portion enters the bottomed cutout 244.

[0129] As noted above, the floating sleeve 200 is held in the L-shaped arm member 2016 by the retaining ring 218. Therefore, the floating sleeve 200 is also indirectly supported by the guide member 250.

[0130] In this case, guide grooves 260 are formed in the guide member 250, and ball grooves 264 are also formed in a slider 262 as a member that is displaced. The slider 262 is displaced relative to the guide member 250 because a plurality of balls 266 perform a sliding movement in the guide grooves 260 and the ball grooves 264.

[0131] Bolt-receiving holes 270, 272 for passing connecting bolts 268 are formed in the slider 262. The connecting bolt 268, which has passed through the bolt-receiving hole 270, is screwed into the bolt-receiving opening 298 of the L-shaped plate 168. On the other hand, the connecting bolt 268, which has passed through the bolt-receiving hole 272, is screwed into a bolt-receiving opening 276 of an L-shaped bracket 274 (described later). Accordingly, the L-shaped plate 168 and the L-shaped bracket 274 are connected to the slider 262.

[0132] In addition, a semicircular cutout 277, which serves to avoid interference with the rivet 256, is formed in the slider 262.

[0133] A ball cover 268, whose side end surfaces are bent at approximately 90°, is arranged to cover the slider 262. A plurality of retaining windows 280 are formed in the side end surfaces. The guide grooves 260 and the ball grooves 264 perform a sliding movement in a state in which the respective balls 266 are inserted into the retaining windows 280.

[0134] A lower stopper member 282 and an upper stopper member 284 are welded, for example, to a lower end surface and an upper end surface of the slider 262. The displacement of the ball cover 278 is regulated by means of the lower stopper member 282 and the upper stopper member 284.

[0135] The slider 262 and the tube 16 are connected via the L-shaped bracket 274. Specifically, the L-shaped bracket 274 includes a roof wall portion 286 (flat portion) and a downwardly hanging wall portion 288 (flat portion) that hangs downward from the roof wall portion 286. The intersection angle of the roof wall portion 286 and the downwardly hanging wall portion 288 forms an angle of approximately 90°.

[0136] The downwardly hanging wall portion 288 is attached (held) to the slider 262 by screwing the connecting bolts 268 into the bolt receiving holes 276 in the manner described above. On the other hand, four tie rod locking holes 240 are formed in the roof wall portion 286, and the pipe 16 is attached (held) to the roof wall portion 286 via the tie rods 60, the heads of which are locked in the respective tie rod locking holes 290.

[0137] The cylinder 180 with a guide mechanism according to the fourth embodiment is essentially constructed as described above. Next, the operation and advantageous effects of the cylinder will be explained.

[0138] During the fastening of the guide mechanism 182 to the cylinder 14 by means of the connecting bolts 268, the slider 262 is connected to the tube via the L-shaped plate 186 and the L-shaped bracket 274. The screwed-in connecting bolts 268 are fully received inside the bolt receiving holes 270, 272. Furthermore, the slider 262 is covered by the ball cover 278, with the balls 266 held in its holding windows 280. At the same time, the ball cover 278 is covered by the guide member 250. Here, the balls 266 are inserted into the holding windows 280, into the ball grooves 264 and the guide grooves 260. Furthermore, the lower stopper member 282 and the upper stopper member 284 are connected to the slider 262.

[0139] Before or after these actions, the shank portion of the rivet 256, which has been previously inserted into the rivet hole 254 and exposed on the rear surface (an end surface facing the downwardly hanging wall portion 242) of the guide member 250, is crushed or folded. Furthermore, the screws 248, which have been passed through the screw insertion holes 252, are screwed into the threaded holes 246. In the manner described above, the linear guide 204 is held on the L-shaped arm member 2016. The crushed shank portion of the rivet 256 enters the cutout 244 at the bottom of the L-shaped arm member 2016.

[0140] Next, the shaft portion 206 of the floating sleeve 200 is passed through the small-diameter hole 226 of the sleeve insertion hole 222 and the retaining ring 218 and inserted into the connecting hole 48 of the piston rod 22. Subsequently, the floating sleeve 200 is rotated by a screwdriver, wrench, or the like inserted into the screw hole 214 of the floating sleeve 200. Accordingly, the threaded portion of the floating sleeve 200 is screwed into the thread of the connecting hole 48.

[0141] At this time, the retaining ring 218 is clamped between the upper surface of the piston rod 22 and the bottom end surface of the locking portion 208 of the floating sleeve 200. At this time, because the retaining ring 218 supports the floating sleeve 200, the floating sleeve 200 is prevented from being pulled out of the sleeve insertion opening 222. Specifically, the floating sleeve 200 is held by the retaining ring 218 on the L-shaped arm member 216.

[0142] Next, the lower end surface of the tube is brought into abutment against a predetermined position of the L-shaped plate 186 above the flat plate 184. At this time, the positions of the tie rod insertion holes 58 of the tube 16 are aligned with the positions of the first tie rod through holes 190 and the tie rod threaded holes 188. Specifically, the first tie rod through holes 190 and the tie rod insertion holes 58 are arranged to connect to the tie rod threaded holes 188.

[0143] In this state, the L-shaped bracket 274 is arranged so that the tie rod locking holes 290 overlap the tie rod insertion holes 58. Furthermore, threaded portions of the tie rods 60 are passed through the second tie rod through holes 230 of the L-shaped arm member 216, the tie rod locking holes 290, and the tie rod insertion holes 58, and are screwed into the tie rod threaded holes 188. The diameters of the head portions of the tie rods 60 are smaller than the diameters of the second tie rod through holes 230, so that the tie rods 60 can easily pass through the second tie rod through holes 230.

[0144] Furthermore, since the diameters of the head portions of the tie rods 60 are larger than the diameters of the tie rod locking holes 290, the head portions of the tie rods 60 are locked at positions near the openings of the tie rod locking holes 290. Accordingly, the tie rods 60 connect the L-shaped bracket 274 to the pipe 16, and also connect the pipe 16 to the flat plate 184 and the L-shaped plate 186. Accordingly, the guide mechanism 182 is attached to the cylinder 14, thereby forming the cylinder 180 with a guide mechanism.

[0145] In this way, the fourth embodiment also facilitates the manufacture of a so-called retrofitted device in which the guide mechanism 182 is attached to an existing cylinder 14. Stepped pins, for example, can also be used to attach the cylinder 180 with the guide mechanism to another element. Specifically, ends of the stepped pins can be inserted into the through holes 192, 194, while other ends of the pins can be inserted into positioning holes of another predetermined element.

[0146] In the fourth embodiment, a side wall of the blocking portion 208 of the floating sleeve 200 is spaced from the inner wall of the small-diameter opening 226, and its head portion 210 is spaced from both the inner wall of the large-diameter opening 228 and the annular stepped portion 224. Specifically, a predetermined clearance is formed between the floating sleeve 200 and the L-shaped arm member 216. Accordingly, within the range of this clearance, the floating sleeve 200 can be displaced relative to the holding portion 202.

[0147] Therefore, at the time when axial misalignment occurs between the floating sleeve 200 and the piston rod 22, the floating sleeve 200 can be connected to the piston rod 22 in such a manner that its central axis coincides with the central axis of the piston rod 22, with the floating sleeve 200 being held in a state of being held by the retaining ring 218 and thus by the holding member 202.

[0148] Furthermore, the fastening inserts 236 of the stepped pins 234 are inserted into the second tie rod through-holes 230. The stepped pins 234 are positioned by abutting their stopper elements 238 against the roof wall portion 220, and their positioning inserts 240 are exposed in an outwardly protruding manner.

[0149] The positioning inserts 240 are inserted into the positioning holes of the workpiece. This allows the workpiece to be positioned.

[0150] In addition, a workpiece (not shown) is held by the L-shaped arm member 216 via bolts or stepped pins or the like, which are inserted through the workpiece holding holes 232. Accordingly, the workpiece is supported by the cylinder 180 with guide mechanism.

[0151] The cylinder 180 with guide mechanism is actuated in the same way as the cylinder 10 with guide mechanism. In particular, when the piston rod 22 and the floating sleeve 200 are at their bottom dead center positions, a working fluid (for example, air) is discharged from the Fig. 5. The piston 20 receives a pressure force from the working fluid supplied to the first chamber 32. This causes the piston 20 and piston rod 22 to rise. At this time, the working fluid held in the second chamber 52 is discharged to the outside via the second port 56.

[0152] As the piston rod 22 rises, the floating sleeve 200 also rises. Since the floating sleeve 200 is held by the retaining ring 218, and since the L-shaped arm member 216 that holds the retaining ring 218 is also held by the guide member 250, the holding portion 202 and the guide member 250 rise, following the rise of the floating sleeve 200. At this time, since the balls 266 perform a sliding movement, the slider 262 is held at its original position. Accordingly, the slider 262 descends relative to the guide member 250.

[0153] When the guide member 250 abuts the upper stop member 284, further upward movement of the guide member 250 is prevented. Specifically, the piston rod 22, the floating sleeve 200, the holding portion 202, and the guide member 250 arrive at their top dead center positions, as shown in Fig. 15. Accordingly, the workpiece is transported by the stroke of the floating sleeve 200 and the piston rod 22.

[0154] When the piston rod 22 positioned at the top dead center and the floating sleeve 200 return to their bottom dead center positions, a working fluid (for example, air) is supplied from the second port 56 to the second chamber 52 (see Fig. 5). The piston 20 receives a pressure force from the working fluid supplied to the second chamber 52 and descends. The working fluid held in the first chamber 32 is discharged to the outside via the first port 54.

[0155] Following the downward movement of the piston 20, the piston rod 22 and the floating sleeve 200 also descend. At the same time, both the holding section 202 and the guide element 250 descend. Since the balls 266 perform a sliding movement at this time, the slider 262 is held in its original position. Accordingly, the slider 262 rises relative to the guide element 250.

[0156] In addition, the guide member 250 abuts against the lower stopper member 282, and the roof wall portion bent in the cutout 244 with the bottom of the L-shaped arm member 216 abuts against the collapsed shaft portion of the rivet 256. Accordingly, upward displacement of the guide member is prevented. Specifically, the piston rod 22, the floating sleeve 200, the holding portion 202, and the guide member 250 arrive at their bottom dead center positions, as shown in Fig. 14. When the floating sleeve 200 and the piston rod 22 return from their top dead center positions to their bottom dead center positions, another workpiece different from the above-mentioned workpiece can be transported.

[0157] When the above actions are performed, the anti-twist precision is also improved for the same reasons discussed in connection with the first embodiment. In other words, the fourth embodiment also achieves the same advantages and effects as the first to fourth embodiments.

[0158] One in Fig. 16 can also be attached to the cylinder 180 with guide mechanism. As shown in Fig. 17, the flange member 300 may be disposed between the L-shaped bracket 274 and the L-shaped arm member 216 and provided such that the tie rods 60 pass through it. As shown in Fig. 18, the flange member 300 can also be used instead of the flat plate 184. In this case, the cylinder 180 with guide mechanism can be attached to a workpiece or other fixed member via the flange member 300. Accordingly, the attachment process is further simplified.

[0159] Furthermore, without using the flat plate 184 or the flange member 300, in the same manner as in the first embodiment, the tie rods 60 can be screwed into the fixed fastening member 62 (see Fig. 3).

[0160] In addition, instead of the stepped pins 234, the shank portions of bolts or the like may be inserted into the second tie rod through holes 230, and a workpiece may be positioned by means of these bolts.

[0161] The present invention is not limited to the first to fourth embodiments described above, and various modifications can be made without departing from the scope of the present invention.

[0162] For example, in all of the first to fourth embodiments, the guide mechanisms 12, 122, 142, 182 are mounted on the cylinder 14 such that the guide member 96 is positioned on the rear surface side of the first port 54 and the second port 56, or in other words, such that a phase shift of 180° exists between both port openings 54, 56 and the guide member 96. However, the guide member 96 may also be arranged to face both port openings 54, 56 (with a phase shift of 0°), or the guide member 96 may be arranged with a phase shift of 90° between the guide member 96 and both ports 54, 56.

[0163] As can be seen, the guide mechanisms 12, 122, 142, 182 can be mounted on the cylinder 14 in any direction. In other words, the degree of freedom in mounting the guide mechanisms 12, 122, 142, 182 is high. Therefore, it is possible to arrange the guide mechanisms 12, 122, 142, 182 in positions that do not interfere with a specific position of the fastening element 62.

[0164] Furthermore, for simplicity and ease of understanding, the piston rod 22 has been shown exposed on the upper side of the tube 16, while its opposite side has been shown arranged on the lower side. However, during actual use of the cylinders 10, 120, 140, 180 with guide mechanisms, there is no particular requirement that the directions in which the piston rod 22 and the floating sleeve 50, 200 extend coincide with the vertical direction. For example, the cylinders 10, 120, 140, 180 with guide mechanisms can be used in orientations in which the piston rod 22 and the floating sleeve 50, 200 extend in a horizontal direction.

[0165] In particular, the upward and downward directions in the description do not necessarily imply a vertical direction during actual use. In actual use, the upward and downward directions may coincide with a horizontal direction, or the cylinders 10, 120, 140, 180 with guide mechanisms may be inclined relative to the vertical direction and the horizontal direction. Of course, the cylinders 10, 120, 140, 180 with guide mechanisms may be used in orientations where the upward and downward directions in the above description correspond to a vertical upward direction and a vertical downward direction, respectively, or conversely, the cylinders 10, 120, 140, 180 with guide mechanisms may be used in orientations where the upward and downward directions in the above description correspond to a vertical downward direction and a vertical upward direction, respectively.

Claims

[1] A cylinder guide mechanism (12) mounted on a cylinder (14) in which a piston rod (22) performs forward and reverse operations in a tube (16), comprising: a floating sleeve (50) configured to perform forward and reverse operations following the forward and reverse operations of the piston rod (22); a holding portion (70) configured to hold the floating sleeve (50); a guide mechanism (72) having a guide element (96) held by the holding section (70) and a displaceable element (98) held on the guide element (96) and configured to be displaced relative to the guide element (96); and a clamp (102) configured to connect the displaceable element (98) and the tube (16). [2] The cylinder guide mechanism (12) according to claim 1, wherein: the holding section (70) comprises a workpiece transport element (80) configured to transport a workpiece and a holding element (78) configured to hold the floating sleeve (50) on the workpiece transport element (80); a sleeve insertion opening (86) into which the floating sleeve (50) is inserted is formed in the workpiece transport element (80); and a clearance (88) exists between an inner wall of the sleeve insertion opening (86) and a side wall of the floating sleeve (50). [3] The cylinder guide mechanism (12) according to claim 2, wherein: a first engagement part (74) is formed on the floating sleeve (50) and a second engagement part (82) which engages with the first engagement part (74) is formed on the holding element (78); and a clearance (84) is provided between the first engagement part (74) and the second engagement part (82). [4] The cylinder guide mechanism (12) according to claim 3, wherein the first engagement part (74) is a circumferential groove (74) formed around the side wall of the floating sleeve (50), and wherein the second engagement part (82) is an insertion portion (82) inserted into the circumferential groove (74). [5] The cylinder guide mechanism (12) according to any one of claims 1 to 4, wherein the bracket (102) is an elbow-shaped member in which two flat portions (104, 106) are connected via a bent portion. [6] The cylinder guide mechanism (12) according to claim 5, wherein one of the flat portions (104) of the bracket (102) abuts against an end surface of the tube (16) at which the piston rod (22) is exposed or against a rear surface on a side opposite the end surface, and wherein a remaining one of the flat portions (106) is connected to the displaceable member (98). [7] The cylinder guide mechanism (12) according to any one of claims 1 to 6, wherein: a connecting element passage opening (90) for passing through a connecting element (60) is formed in the holding section (70), wherein the connecting element (60) is designed to connect the pipe (16) to a fixed element (62), and the connecting element passage opening (90) has a larger diameter than a connecting element insertion opening (58) formed in the tube (16) and through which the connecting element (60) is inserted. [8] The cylinder guide mechanism (182) according to claim 7, further comprising a positioning member (234) inserted into the connecting member through-hole (90) and configured to position a workpiece. [9] The cylinder guide mechanism (12) according to any one of claims 1 to 8, wherein a workpiece holding opening (91) is formed in the holding portion (70) and is configured to hold a workpiece. [10] A cylinder (10) with a guide mechanism comprising a cylinder (14) in which a piston rod (22) performs forward and backward operations relative to a tube (16), and a cylinder guide mechanism (12) attached to the cylinder (14), the cylinder guide mechanism (12) having the following elements: a floating sleeve (50) configured to perform forward and reverse operations following the forward and reverse operations of the piston rod (22); a holding portion (70) configured to hold the sleeve (50); a guide mechanism (72) having a guide element (96) held by the holding section (70) and a displaceable element (98) held on the guide element (96) and configured to be displaced relative to the guide element (96); and a clamp (102) connected to the movable element (98) and the tube (16). [11] The cylinder (10) with guide mechanism according to claim 10, wherein: the holding section (70) comprises a workpiece transport element (80) configured to transport a workpiece and a holding element (78) configured to hold the floating sleeve (50) on the workpiece transport element (80); a sleeve insertion opening (86) into which the floating sleeve (50) is inserted is formed in the workpiece transport element (80); and a clearance (88) is provided between an inner wall of the sleeve insertion opening (86) and a side wall of the floating sleeve (50). [12] The cylinder (10) with guide mechanism according to claim 11, wherein: a first engagement part (74) is formed on the floating sleeve (50) and a second engagement part (82) which engages with the first engagement part (74) is formed on the holding element (78); and a clearance (84) is provided between the first engagement part (74) and the second engagement part (82). [13] The cylinder (10) with guide mechanism according to claim 12, wherein the first engagement part (74) is a circumferential groove (74) formed around a side wall of the floating sleeve (50), and wherein the second engagement part (82) is an insertion portion (82) inserted into the circumferential groove (74). [14] The cylinder (10) with guide mechanism according to one of claims 10 to 13, wherein the bracket (102) is an elbow-shaped member in which two flat portions (104, 106) are connected via a bent portion. [15] The cylinder (10) with guide mechanism according to claim 14, wherein one of the flat portions (104) of the bracket (102) abuts against an end surface of the tube (16) at which the piston rod (22) is exposed or against a rear surface on a side opposite to the end surface, and wherein a remaining one of the flat portions (106) is connected to the displaceable member (98). [16] The cylinder (10) with guide mechanism according to one of claims 10 to 15, wherein: a connecting element passage opening (90) for passing a connecting element (60) is formed in the holding part (70), wherein the connecting element (60) is designed to connect the tube (16) to a fixed element (62), and wherein a connecting element insertion opening (58) is formed for inserting the connecting element (60) in the tube (16); and the connecting element passage opening (90) has a larger diameter than the connecting element (60) and the connecting element insertion opening (58). [17] The cylinder (10) with guide mechanism according to claim 16, further comprising a positioning element (234) which is inserted into the connecting element through-hole (90) and is designed to position a workpiece. [18] The cylinder (10) with guide mechanism according to one of claims 10 to 17, wherein a workpiece holding opening (91) is formed in the holding part (70) and is designed to hold a workpiece.

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