Fluid pressure actuator and method for manufacturing fluid pressure actuator

Abstract

To provide a fluid pressure actuator that prevents leakage of fluid while pressure of the fluid is applied to a tube, and a method of manufacturing the fluid pressure actuator.SOLUTION: A fluid pressure actuator 20 includes: a tube 24 pair expanded and contracted by fluid pressure and having a pair of tubes 24 arranged in parallel; a sealing member 30 in which an insertion part 50 pair with insertion parts 50 to which end parts in the axial direction X of the tubes 24 are inserted, respectively is formed and that seal the end parts of the respective tubes 24; a caulking member 36 for fixing the tube 24 pair to the insertion part 50 pair from an outer side of a sleeve 26; and a filling material 60 disposed in a recessed space 70 on an outer periphery of the insertion part 50 pair astride opposing portions viewed from the axial direction X and coming into contact with the tube 24 pair and the sleeve 26 to fill a gap.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a fluid pressure actuator and a method for manufacturing a fluid pressure actuator.

Background Art

[0002] Patent Document 1 discloses a fluid pressure actuator including a cylindrical tube that expands and contracts by the pressure of a fluid, a stretchable structure in which fiber cords oriented in a predetermined direction are woven, a sleeve that covers the outer peripheral surface of the tube, and a sealing member that seals the end portions in the axial direction of the tube. The tubes are provided in a plurality side by side along a direction orthogonal to the axial direction, and at opposing portions where adjacent tubes face each other, a restraint member is provided extending from one end side to the other end side in the axial direction of the tube. The restraint member resists compression along the axial direction and is deformable in the orthogonal direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As a fluid pressure actuator, it is desirable that the fluid does not easily leak when the tube is under the pressure of the fluid.

[0005] An object of the present disclosure is to provide a fluid pressure actuator in which the fluid does not easily leak when the tube is under the pressure of the fluid and a method for manufacturing the fluid pressure actuator.

Means for Solving the Problems

[0006] The fluid pressure actuator of the first aspect includes a pair of tubes arranged in parallel that expand and contract by the pressure of a fluid, a sleeve that covers the outer peripheral surfaces of the pair of tubes and expands the tubes in the radial direction while restricting axial elongation of the tubes due to the expansion of the tubes, a pair of insertion portions into which the axial ends of the tubes of the pair of tubes are respectively inserted, a sealing member that seals the ends of the respective tubes, a restraining member provided across the axial one end side to the other end side of the pair of tubes and sandwiched between the opposing portions where the respective tubes face each other, a caulking member that fixes the pair of tubes to the pair of insertion portions from the outside of the sleeve, and a filler that is disposed in a concave space on the outer periphery of the pair of insertion portions across the opposing portion when viewed from the axial direction and contacts the pair of tubes and the sleeve to fill the gap.

[0007] When the fluid pressure actuator of this aspect is assembled by caulking with a caulking member, it includes a filler that is disposed in a concave space on the outer periphery of the pair of insertion portions and contacts the pair of tubes and the sleeve to fill the gap. Thereby, the tube is pressed against the insertion portion by the caulking member via the sealing member. Therefore, according to the fluid pressure actuator of this aspect, when fluid is supplied inside the tube, it is difficult for the fluid to leak from between the tube and the insertion portion.

[0008] The fluid pressure actuator of the second aspect is the fluid pressure actuator described in the first aspect, and in the axial direction, it is a length that covers from one end to the other end of the pair of insertion portions.

[0009] In the fluid pressure actuator of this aspect, the axial length of the filler is set to a length that covers from one end to the other end of the pair of insertion portions. Thereby, compared with the case where the axial length of the filler is shorter than the pair of insertion portions, a filler that presses the entire axial length of the pair of insertion portions is obtained.

[0010] In the fluid pressure actuator of the third aspect, in the fluid pressure actuator described in the second aspect, the contact portion of the filler that contacts the insertion portion through the tube follows the shape of the insertion portion.

[0011] In the fluid pressure actuator of this aspect, since the shape of the contact portion follows the shape of the insertion portion, the tube is in close contact with the insertion portion by being pressed by the filler. Therefore, when fluid is supplied inside the tube, it is less likely for the fluid to leak from between the tube and the sealing member compared to the case where the shape of the contact portion does not follow the shape of the insertion portion.

[0012] In the fluid pressure actuator of the fourth aspect, in the fluid pressure actuator described in the second aspect, the filler is deformed following the shape of the pair of insertion portions by the pressing from the outside of the sleeve of the caulking member.

[0013] In the fluid pressure actuator of this aspect, since the caulking member deforms the filler so as to follow the shape of the pair of insertion portions when fixing the pair of tubes to the pair of insertion portions, the tube is in close contact with the insertion portion by being pressed by the filler. Therefore, when fluid is supplied inside the tube, it is less likely for the fluid to leak from between the tube and the sealing member compared to the case where the filler does not deform before and after the time when the caulking member fixes the pair of tubes to the pair of insertion portions.

[0014] The manufacturing method of the fluid pressure actuator according to the fifth aspect includes a pair of tubes arranged in parallel that expand and contract by the pressure of a fluid. An insertion portion pair having insertion portions into which the end portions in the axial direction of the tubes of a sealing member for sealing the end portions of the tube pair are respectively inserted is formed. A procedure of inserting into the insertion portion pair, a procedure of providing a restraint member at an opposing portion where the respective tubes face each other from one end side to the other end side in the axial direction of the tube pair, a procedure of disposing a filler in a concave space on the outer periphery of the insertion portion pair across the opposing portion as viewed from the axial direction, a procedure of covering the outer peripheral surface of the tube pair with a sleeve which is a stretchable structure body in which a fiber cord oriented in a predetermined direction is woven, and a procedure of filling the gap between the tube pair and the sleeve with the filler while fixing the tube pair to the insertion portion pair using a caulking member from the outside of the sleeve.

[0015] The manufacturing method of the fluid pressure actuator according to this aspect includes a procedure of disposing a filler in a concave space on the outer periphery of the insertion portion pair across the opposing portion as viewed from the axial direction, and a procedure of filling the gap between the tube pair and the sleeve with the filler while fixing the tube pair to the insertion portion pair. Therefore, according to the manufacturing method of the fluid pressure actuator according to this aspect, a fluid pressure actuator in which fluid is less likely to leak from between the tube and the insertion portion when fluid is supplied inside the tube can be obtained.

Effect of the Invention

[0016] According to the present disclosure, a fluid pressure actuator in which fluid is less likely to leak from between the tube and the sealing member when fluid is supplied inside the tube is provided.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments for realizing the technology of the present disclosure will be described in detail with reference to the drawings.

[0019] In addition, for components and processes that perform the same functions, the same reference numerals are given throughout the drawings, and duplicate explanations may be omitted as appropriate. Further, the present disclosure is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present disclosure.

[0020] Note that the "arrow Z+ direction" and "arrow Z- direction" in each drawing are examples of the axial direction X in the present disclosure. Also, the "arrow Y+ direction" and "arrow Y- direction" in each drawing are examples of one of the alignment directions Z in the present disclosure. Further, the "arrow X+ direction" and "arrow X- direction" in each drawing are examples of the width direction Y in the present disclosure.

[0021] In the following description, "one side" refers to the "+" side of the arrow X, arrow Y, and arrow Z, and "the other side" refers to the "-" side of the arrow X, arrow Y, and arrow Z. That is, when the axial direction X, the alignment direction Z, and the width direction Y are described without adding "one side" or "the other side", it may refer to both the "+" side and the "-" side.

[0022] <Configuration of the fluid pressure actuator 20> FIG. 1 shows a fluid pressure actuator 20 according to an embodiment of the present disclosure. The fluid pressure actuator 20 includes an actuator main body portion 22, a sealing member 30, and a sealing member 31.

[0023] As also shown in FIG. 2, the actuator main body portion 22 has a pair of tubes 24, a sleeve 26, a restraint member 28, a locking ring 34, and a caulking member 36. The fluid pressure actuator 20 according to the present embodiment further has a pair of packing materials 60.

[0024] The tube 24 is a cylindrical member that can expand and contract due to elastic deformation, and expands and contracts due to a change in the pressure of the internal fluid. Note that in the state where the fluid pressure actuator 20 is assembled, the longitudinal direction of the tube 24 coincides with the axial direction X. Also, as shown in FIG. 2, the tubes 24 are arranged in parallel in the state where the fluid pressure actuator 20 is assembled.

[0025] Note that the tube 24 can be made of an elastic material such as butyl rubber. As the fluid supplied to the tube 24, air can be used. In this case, the fluid pressure actuator 20 becomes a pneumatic actuator. When the fluid pressure actuator 20 is driven hydraulically, it is preferably at least one selected from the group consisting of NBR (nitrile rubber) with high oil resistance, hydrogenated NBR, chloroprene rubber, and epichlorohydrin rubber.

[0026] The sleeve 26 is a cylindrical member that covers the outer periphery of the tube 24. The sleeve 26 is a stretchable structure in which fiber cords oriented in a predetermined direction are woven, and the oriented cords intersect at a predetermined angle θ with respect to the axial direction X. By having such a shape, the sleeve 26 undergoes a pantograph deformation that changes the angle θ and follows the contraction and expansion of the tube 24 while restricting the contraction and expansion of the tube 24.

[0027] As the cords constituting the sleeve 26, it is preferable to use fiber cords of aromatic polyamide (aramid fiber) or polyethylene terephthalate (PET). However, it is not limited to such types of fiber cords, and for example, cords of other high-strength fibers such as PBO fiber (polyparaphenylene benzobisoxazole) may also be used.

[0028] The restraint member 28 is provided between a pair of tubes 24. The restraint member 28 is in the shape of a long plate and is arranged such that its longitudinal direction is along the axial direction X of the tube 24, and it is arranged from one end to the other end of the tube 24 while touching a part of the outer periphery of the tube 24. More specifically, as shown in FIG. 12 described later, the restraint member 28 is sandwiched between the opposing portions where a pair of tubes 24 face each other in a state where the fluid pressure actuator 20 is assembled.

[0029] Note that the restraining member 28 is formed of a material that does not expand or contract under pressure and is capable of flexurally deforming in a direction in which the ends approach each other. As the restraining member 28, a so-called leaf spring can be used. The dimensions of the leaf spring are determined according to the size and specifications of the fluid pressure actuator 20, such as the magnitude of the force that causes the actuator main body 22 to bend and deform (see also FIG. 12). Also, the material of the leaf spring is not particularly limited, but typically, a material that is easily flexurally deformable and resistant to compression, such as a metal such as stainless steel, may be used. Alternatively, it may be formed of a thin plate of carbon fiber reinforced plastic (CFRP) or the like.

[0030] The locking ring 34 is a ring-shaped member that is disposed outside the sleeve 26 so as to sandwich the sleeve 26 between itself and a locking portion 58 described later, and locks the sleeve 26 to the semi-base end portion 40. As a result, the sleeve 26 is folded back to the outer periphery via the locking ring 34. Note that the locking ring 34 can be made of a material such as metal, hard plastic, fiber, or rubber.

[0031] The caulking member 36 is disposed so as to cover a portion of the outer periphery of the actuator main body 22 where the insertion portion 50 is inserted, and crimps the actuator main body 22 to the insertion portion 50 described later. As a result, the actuator main body 22 is fixed to the insertion portion 50 of a sealing member 30 described later. As the caulking member 36, metals such as aluminum alloy, brass, and iron can be used.

[0032] Note that the description of the filler 60 will be given later.

[0033] The caulking member 36 is disposed so as to cover a portion of the outer periphery of the actuator main body 22 where the insertion portion 50 is inserted, and crimps the actuator main body 22 to the insertion portion 50 described later. As a result, the actuator main body 22 is fixed to the insertion portion 50 of a sealing member 30 described later. As the caulking member 36, metals such as aluminum alloy, brass, and iron can be used.

[0034] As shown in FIGS. 3 to 7, the sealing member 30 has a first sealing member 30A and a second sealing member 30B that are divided at the middle in the arrangement direction Z. First, the first sealing member 30A will be described with reference to FIGS. 3 to 5. In the following description, the side where the actuator main body 22 is located as viewed from the sealing member 30 and the sealing member 31 may be referred to as the inner side in the axial direction X.

[0035] The first sealing member 30A has a semi-base end portion 40 and an insertion portion 50. The semi-base end portion 40 has a mounting portion 32, a locking portion 58, and a large-diameter portion 54.

[0036] As shown in FIGS. 3 and 4, the mounting portion 32, the locking portion 58, and the large-diameter portion 54 are each formed in a substantially semi-cylindrical shape. Also, the centers of the arcs in the mounting portion 32, the locking portion 58, and the large-diameter portion 54 (the center in the full circle when the arc extends over the entire circumference) are arranged along the axial direction X and coincide with the central axis S of the fluid pressure actuator 20 in the assembled state as described later. In the following description, the chord side (arrow Z− side) of the semi-circle in the mounting portion 32, the locking portion 58, and the large-diameter portion 54 may be referred to as the "back side", and the opposite side (arrow Z+ side) may be referred to as the "front side". Also, in the following description, when referring to the diameters of the mounting portion 32, the locking portion 58, and the large-diameter portion 54, it shall refer to the diameter of the semi-circle (twice the radius of the semi-circle).

[0037] The dividing surface 33, which is the surface on the back side of the semi-base end portion 40, is a flat surface along the axial direction X passing through the midpoint in the arrangement direction Z of the sealing member 30 as shown in FIG. 6. That is, the dividing surface 33 overlaps with the surface that divides the sealing member 30 into the first sealing member 30A and the second sealing member 30B in the arrangement direction Z as shown in FIG. 6 described later.

[0038] The attachment portion 32 has a diameter larger than the outer diameter of the tube 24, and an insertion portion 50 extends axially in the X direction from one end side of the attachment portion 32. Further, the attachment portion 32 has a flow path R that communicates from the connection hole H on the front side through the radial center portion of the insertion portion 50 to the other end side in the X direction (arrow X+ side) (see also Fig. 6). An air supply hose (not shown) is connected to the connection hole H, and compressed air is supplied to the flow path R. The through hole 32T is a hole that penetrates from the front surface to the back surface of the attachment portion 32 on the outside in the X direction of the connection hole H of the attachment portion 32 (the right back side in the drawing in Figs. 3 and 4). The mounting hole 32I is a hole that penetrates from the outer surface of the attachment portion 32 in the X direction (the front left surface in Fig. 2) to the through hole 32T. The mounting hole 32I is, for example, a female thread into which a male threaded member (not shown) is inserted. The fluid pressure actuator 20 is fixed to a shaft member (not shown) by the male threaded member pressing the shaft member (not shown) passed through the through hole 32T.

[0039] The locking portion 58 is a portion that extends from the inner surface of the attachment portion 32 in the X direction toward the other side in the X direction, and has a diameter smaller than that of the attachment portion 32 as shown in Figs. 3 and 4. Note that the length of the locking portion 58 in the X direction is appropriately set according to the shape of the above-described locking ring 34.

[0040] The large-diameter portion 54 is a portion that extends from the surface of the other end side of the locking portion 58 toward the other side in the X direction, and has a diameter larger than that of the locking portion 58 as shown in Figs. 3 and 4. Note that the length of the large-diameter portion 54 in the X direction is appropriately set according to the shape of the above-described caulking member 36.

[0041] A groove-shaped insertion groove 42 is formed in the dividing surface 33. As shown in FIG. 4, the insertion groove 42 is formed on the back side of the semi-base end portion 40, extending from the surface on the other end side of the large-diameter portion 54 toward the other end side in the axial direction X, and is a groove-shaped portion that is open on the large-diameter portion 54 side in the axial direction X. The shape of the insertion groove 42 is appropriately set according to the shape of the restraining member 28. More specifically, the length W in the width direction Y, which is the distance between the side wall surfaces 42S in the insertion groove 42, is slightly larger than the size in the width direction Y of the restraining member 28. Also, the size T in the depth direction of the insertion groove 42, which is the length from the dividing surface 33 to the flat surface 42F in the insertion groove 42, is slightly larger than half of the thickness direction of the restraining member 28. Further, the length D in the axial direction X of the insertion groove 42, which is the length from the insertion portion 50 side to the bottom surface 42B in the insertion groove 42, is set such that in the fluid pressure actuator 20 after assembly, the restraining member 28 is not compressed in the axial direction X and the restraining member 28 is sandwiched to such an extent that one end does not come out of the insertion groove 42. An insertion portion 42H into which the end portion of the restraining member 28 can be inserted is formed by the insertion groove 42 of the first sealing member 30A and the insertion groove 42 of the second sealing member 30B described later.

[0042] As shown in FIG. 4, the boss 44 is a portion that protrudes rearward from the surface on the back side of the mounting portion 32, and is, for example, substantially cylindrical in shape. Also, as shown in FIG. 4, the recess 46 is a circular hole that is recessed toward the front side at a position on the back surface of the mounting portion 32 that is line-symmetrical with the boss 44 with respect to the central axis of the fluid pressure actuator 20. Note that the diameter of the recess 46 is slightly larger than the diameter of the boss 44, and the depth of the recess 46 is larger than the height of the boss 44.

[0043] As shown in FIGS. 3 to 6, the insertion portion 50 is formed with a plurality of tapered portions that taper inward in the axial direction X connected in the axial direction X. Also, the tapered portion of the insertion portion 50 has an oval shape that is long in the width direction Y when viewed from the axial direction X. Further, the insertion portion 50 is inserted into one end side of the tube 24.

[0044] Incidentally, the area of the insertion portion 50 viewed from the axial direction X is slightly larger than the cross-sectional area of the flow path R of the tube 24. More specifically, in a state where the insertion portion 50 is inserted into one end side of the tube 24, the portion having the large diameter of the tapered portion of the tube 24 is shaped such that the tube 24 is deformed along the ellipse and still bites into the inner surface of the tube 24.

[0045] As the first sealing member 30A, a metal such as stainless steel can be preferably used, but it is not limited to such a metal, and a hard plastic material or the like may be used.

[0046] As shown in FIG. 2, the second sealing member 30B is a member having a shape that is symmetric with respect to the first sealing member 30A. As shown in FIG. 6, the first sealing member 30A and the second sealing member 30B can be overlapped with each other on the back surfaces. More specifically, in FIG. 6, the boss 44 of the first sealing member 30A fits into the recess 46 of the second sealing member 30B, and the boss 44 of the second sealing member 30B fits into the recess 46 of the first sealing member 30A, whereby the first sealing member 30A and the second sealing member 30B are overlapped.

[0047] Then, as shown in FIG. 6, in a state where the first sealing member 30A and the second sealing member 30B are overlapped with each other at the split surfaces 33, the combination of each pair of the insertion portions 50 is an example of the "insertion portion pair" in the embodiment. In a state where the first sealing member 30A and the second sealing member 30B are overlapped, the sealing member 30 which is a combination of the first sealing member 30A and the second sealing member 30B is an example of the "sealing member pair" in the present embodiment. Also, as shown in FIG. 2, the pair of tubes 24 respectively inserted into the pair of insertion portions 50 is an example of the "tube pair" in the present embodiment. Further, as shown in FIG. 6, the state where the semi-base end portions 40 are combined is an example of the "base end portion" in the present embodiment. Also, as shown in FIG. 6, the state where the insertion grooves 42 face each other is an example of the "base end portion" in the present embodiment.

[0048] The sealing member 31 provided on the other end side (the right side in the drawing in FIG. 1) in the axial direction X of the fluid pressure actuator 20 has a lid portion 38 and a pair of insertion portions 50.

[0049] The lid portion 38 of the sealing member 31 is the same as the mounting portion 32 of the sealing member 30, except that the connection hole H and the flow path R are not formed in the mounting portion 32 of the sealing member 30 and the tip is shaped like an R. Further, the sealing member 31 is the same as the sealing member 30, except that the pair of insertion portions 50 are integrated with the lid portion 38. That is, the pair of insertion portions 50 in the sealing member 31 are another example of the "insertion portion pair" in the present embodiment.

[0050] As shown in FIGS. 8 and 9, the filler 60 has an outer contact portion 64 that bulges outward and an inner contact portion 62 that is recessed inward.

[0051] As shown in FIG. 8, the outer contact portion 64 is a portion that bulges in an arc shape when the filler 60 is viewed from the front. The arc shape of the outer contact portion 64 is shaped to follow the inner diameter of the caulking member 36.

[0052] As shown in FIG. 8, the inner contact portion 62 is a portion that is recessed in an arc shape from the corner portion of the surface on the opposite side of the outer contact portion 64 when the filler 60 is viewed from the front. The arc shape of the inner contact portion 62 is shaped to follow the rounding formed on both sides in the width direction Y of the insertion portion 50. That is, the inner contact portion 62 is an example of the "contact portion" according to the present embodiment.

[0053] Further, the length L of the filler 60 shown in FIG. 9 is made equal to the length in the axial direction X of the insertion portion 50.

[0054] Note that, as will be described later, the filling material 60 is not particularly limited as long as it can transmit the force pressed from the caulking member 36 through the sleeve 26 to the pair of insertion portions 50 through the pair of tubes 24 when the caulking member 36 is caulked. As an example of the material of the filling material 60, it is formed using a material such as polypropylene (PP) resin, which is a thermoplastic resin, or cork.

[0055] Subsequently, the assembly procedure of the fluid pressure actuator 20 in the present embodiment will be described.

[0056] <Assembly of the fluid pressure actuator 20> As shown in FIGS. 2 and 10 to 13, on one end side of the fluid pressure actuator 20 in the present embodiment, the sealing member 30 and the actuator main body portion 22 are assembled as follows.

[0057] First, as shown in FIGS. 10 and 11, the insertion portions 50 of the first sealing member 30A and the second sealing member 30B are inserted into the respective ones of the pair of tubes 24 until one end abuts against the large diameter portion 54.

[0058] Also, as shown in FIG. 10, the first sealing member 30A and the second sealing member 30B are overlapped, and one end of the restraining member 28 is inserted into the insertion portion 42H (the portion where the insertion grooves 42 face each other). As a result, the movement of the restraining member 28 in one direction (the semi-base end portion 40 side) of the arrangement direction W, the width direction Y, and the axial direction X is restricted by the side wall surface 42S, the flat surface 42F, and the bottom surface 42B of the insertion portion 42H. In other words, the insertion portion 42H positions the restraining member 28 along the axial direction X and sandwiches the restraining member 28 between the opposing portions of the pair of tubes 24.

[0059] By the way, in a state where the pair of insertion portions 50 shown in FIG. 11 are inserted into the tubes 24 respectively, a concave space 70 is formed on the outer periphery of the pair of insertion portions 50 across the opposing portions where the insertion portions 50 face each other.

[0060] Here, in the present embodiment, as shown in FIG. 10, when viewed from the axial direction X, the filler 60 is disposed across the opposing portions of the 24 pairs of tubes. More specifically, on both sides in the width direction of the restraining member 28, the inner contact portions 62 of the pair of fillers 60 are respectively arranged so as to contact the 24 pairs of tubes. In other words, in the present embodiment, the fillers 60 are respectively disposed in the concave spaces 70 formed on the outer peripheries of the 50 pairs of insertion portions. In other words, the fillers 60 are in contact with the 24 pairs of tubes and the sleeves 26 within the range of the axial length in the X direction of the 50 pairs of insertion portions, filling the gaps in the concave spaces 70.

[0061] Next, while draping the sleeve 26 up to the locking portions 58 of the tubes 24 and the sealing member 30, the outer peripheral surface of the restraining member 28 is covered, and the locking ring 34 is attached at the position of the locking portion 58 from the radially outer side of the sleeve 26, thereby locking the sleeve 26 to the locking portion 58.

[0062] Next, the sleeve 26 is folded back up to the insertion portion 50 of the sealing member 30 so that the locking ring 34 is on the inner side, and the caulking member 36 is disposed from the radially outer side of the sleeve 26 so as to span the insertion portion 50 and the locking portion 58, and the filler 60 is caulked together with the caulking machine (not shown). As a result, at one end in the axial direction X of the actuator main body portion 22, the tubes 24, the restraining member 28, the sleeve 26, and the filler 60 are fixed to the sealing member 30. In other words, in the present embodiment, by caulking the filler 60 together with the tubes 24, the restraining member 28, and the sleeve 26, the gaps with the 24 pairs of tubes and the sleeve 26 are filled.

[0063] Next, on the other side in the axial direction X of the tubes 24, the sleeve 26, and the restraining member 28, the restraining member 28 is inserted into the insertion portion 42H in the sealing member 31.

[0064] Next, while taking care that the restraining member 28 does not come off from the insertion portion 42H of the sealing member 31, each of the pair of insertion portions 50 of the sealing member 31 is inserted into the other side in the axial direction X of the pair of tubes 24.

[0065] Next, while draping the sleeve 26 up to the locking portion 58 of the tube 24 and the sealing member 31, cover the outer peripheral surface of the restraining member 28, and attach the locking ring 34 from the radially outer side of the sleeve 26 at the position of the locking portion 58, thereby locking the sleeve 26 to the locking portion 58.

[0066] Next, fold back the sleeve 26 up to the insertion portion 50 of the sealing member 31 so that the locking ring 34 is on the inner side, and arrange the caulking member 36 from the radially outer side of the sleeve 26 so as to span the insertion portion 50 and the locking portion 58, and crimp it with a crimping machine (not shown). Thereby, at the other end in the axial direction X of the actuator main body portion 22, the tube 24, the restraining member 28, and the sleeve 26 are fixed to the sealing member 31.

[0067] By sealing one end and the other end of the tube 24 to the sealing member 30 and the sealing member 31 by the above procedure, the fluid pressure actuator 20 is assembled.

[0068] Subsequently, the operation of the fluid pressure actuator 20 in the present disclosure will be described.

[0069] <Operation of the fluid pressure actuator 20> As shown in FIG. 12, the fluid pressure actuator 20 is used such that the sealing member 30 on one end side is fixed to a robot hand or the like (not shown), and the sealing member 31 on the other end side becomes a free end.

[0070] First, with the airtightness of the second sealing member 30B released, when compressed air is introduced from the connection hole H of the first sealing member 30A, the pressure in the tube 24 connected to the first sealing member 30A increases. The tube 24 connected to the first sealing member 30A elastically deforms and expands due to the increase in internal pressure. The sleeve 26 undergoes a pantograph deformation so that the angle θ increases, and a force acts in the direction of shortening the length of the actuator main body 22. At this time, since the shortening of the actuator main body 22 is restricted by the restraining member 28 disposed at the opposing portion where the pair of tubes 24 are arranged, the outer peripheral wall on the side where the first sealing member 30A is disposed shortens when viewed from the axial direction X. As a result, the restraining member 28 bends and deforms, and as shown by the two-dot chain line in FIG. 12, the entire actuator main body 22 curves toward the left side of the drawing.

[0071] Similarly, with the airtightness of the first sealing member 30A released, when compressed air is introduced from the connection hole H of the second sealing member 30B, the outer peripheral wall on the side where the second sealing member 30B is disposed shortens for the actuator main body 22 when viewed from the axial direction X. As a result, the restraining member 28 bends and deforms, and as shown by the two-dot chain line in FIG. 12, the entire actuator main body 22 curves toward the right side of the drawing.

[0072] In the present disclosure, since the restraining member 28 has a length in the width direction Y, it is difficult to bend in a direction other than the plate thickness direction, that is, the arrangement direction Z intersecting the axial direction X in the sealing members 30 and 31.

[0073] Thus, in the fluid pressure actuator 20 of the present embodiment, by supplying compressed air to the tube 24 of the first sealing member 30A or the second sealing member 30B, the fluid pressure actuator 20 can be bent and deformed toward the side of the sealing member 30 to which compressed air is supplied. In other words, the fluid pressure actuator 20 in the present embodiment can be bent and deformed toward both sides in the arrangement direction Z by supplying compressed air to any one of the sealing members 30.

[0074] Further, as shown in FIG. 13, when viewing the axial cross-section of the insertion portion 50 of the assembled fluid pressure actuator 20, a pair of packing members 60 are respectively arranged in contact with the sleeve 26 and the pair of tubes 24. In other words, the pair of packing members 60 are pressed from the caulking member 36 via the sleeve 26 and contact the pair of insertion portions 50 via the tubes 24, thereby pressing the tubes 24 against the respective insertion portions 50.

[0075] Subsequently, the operation and effects of the fluid pressure actuator 20 according to the present disclosure will be described.

[0076] <Operation and effects> When the fluid pressure actuator 20 of the present embodiment is assembled by caulking with the caulking member 36, it is disposed in the concave space 70 on the outer periphery of the pair of insertion portions 50 and includes a packing member 60 that contacts the pair of tubes 24 and the sleeve 26 to fill the gap. Thereby, the tube 24 is pressed against the insertion portion 50 by the caulking member 36 via the sealing member 30. Therefore, according to the fluid pressure actuator 20 of the present embodiment, when fluid is supplied inside the tube 24, it is difficult for the fluid to leak from between the tube 24 and the insertion portion 50.

[0077] Further, in the fluid pressure actuator 20 of the present embodiment, the length of the packing member 60 in the axial direction X is set to cover the length from one end to the other end of the pair of insertion portions 50. Thereby, compared with the case where the length of the packing member 60 in the axial direction X is shorter than the pair of insertion portions 50, a packing member 60 that presses the entire length of the pair of insertion portions 50 in the axial direction X can be obtained.

[0078] Further, in the fluid pressure actuator 20 of the present embodiment, since the shape of the contact portion follows the shape of the insertion portion 50, the tube 24 is in close contact with the insertion portion 50 by being pressed by the packing member 60. Therefore, compared with the case where the shape of the contact portion does not follow the shape of the insertion portion 50, when fluid is supplied inside the tube 24, it is difficult for the fluid to leak from between the tube 24 and the sealing member 30.

[0079] In addition, the manufacturing method of the fluid pressure actuator 20 according to the present embodiment includes a procedure of disposing the filler 60 in the concave space 70 on the outer periphery of the pair of insertion portions 50 across the opposing portions when viewed from the axial direction X, and a procedure of filling the gap between the pair of tubes 24 and the sleeve 26 with the filler 60 while fixing the pair of tubes 24 to the pair of insertion portions 50. Therefore, also according to the manufacturing method of the fluid pressure actuator 20 according to the present embodiment, a fluid pressure actuator 20 in which fluid is less likely to leak from between the tube 24 and the insertion portion 50 when fluid is supplied inside the tube 24 can be obtained.

[0080] [First Modification Example] In addition, in the above description, the shape of the filler 60 has followed the shape of the insertion portion 50 before being caulked and assembled by the caulking member 36, but the technology of the present disclosure is not limited to this. For example, the filler 60 may not follow the shape of the insertion portion 50 before being caulked by the caulking member 36, and may be deformed to follow the shape of the insertion portion 50 by being caulked together with the tube 24 by the caulking member 36. In other words, the filler 60 may be deformed to follow the shape of the insertion portion 50 by the pressing from the outside of the sleeve 26 of the caulking member 36. In this case, the filler 60 may be a member that plastically deforms when caulked, or may be a member that elastically deforms when caulked.

[0081] In addition, in the fluid pressure actuator 20 of this modification example, since the filler is deformed so as to follow the shape of the pair of insertion portions when the caulking member fixes the pair of tubes to the pair of insertion portions, the tube is in close contact with the insertion portion by being pressed by the filler. Therefore, compared with the case where the filler does not deform before and after the time when the caulking member fixes the pair of tubes to the pair of insertion portions, fluid is less likely to leak from between the tube and the sealing member when fluid is supplied inside the tube.

[0082] [Second Modification Example] Further, in the above description, the length of the packing material 60 in the axial direction X was set to the length of the pair of insertion portions 50 in the axial direction X. However, the technology of the present disclosure is not limited thereto. When the packing material 60 is caulked by the caulking member 36, the length is not limited as long as it can contact the pair of sleeves 26 and tubes 24 and press the pair of tubes 24.

[0083] Further, in the above description, the inner contact portion 62 of the packing material 60 that contacts the insertion portion 50 via the tube 24 was assumed to follow the shape of the insertion portion 50. However, the technology of the present disclosure is not limited thereto. When the packing material 60 is caulked by the caulking member 36, the shape of the inner contact portion 62 is not particularly limited as long as it can contact the pair of sleeves 26 and tubes 24 and press the pair of tubes 24. For example, the shape of the inner contact portion 62 may be linear when viewed from the axial direction X, or may bulge toward the pair of insertion portions 50.

[0084] Further, in the above description, the outer contact portion 64 of the packing material 60 that contacts the insertion portion 50 via the tube 24 was assumed to follow the shape inside the caulking member 36. However, the technology of the present disclosure is not limited thereto. When the packing material 60 is caulked by the caulking member 36, the shape of the outer contact portion 64 is not particularly limited as long as it can contact the pair of sleeves 26 and tubes 24 and press the pair of tubes 24. For example, the shape of the outer contact portion 64 may be linear when viewed from the axial direction X, or may be concave toward the inner side in the radial direction.

[0085] Even in these modified examples, those having the same configuration as the present embodiment can obtain the same operations and effects as the present embodiment.

[0086] As described above, the embodiments of the present disclosure have been described with reference to the accompanying drawings. However, it is obvious that those having ordinary knowledge in the technical field to which the present disclosure pertains can conceive of various modification examples or application examples within the scope of the technical idea described in the claims. Naturally, these are also understood to belong to the technical scope of the present disclosure.

Explanation of Reference Numerals

[0087] 20 Fluid pressure actuator, 22 Actuator main body part, 24 Tube, 26 Sleeve, 28 Restraining member, 30 Sealing member, 30A First sealing member, 30B Second sealing member, 31 Sealing member, 32 Mounting part, 32T Through hole, 32I Mounting hole, 34 Locking ring, 36 Crimping member, 38 Cover part, 40 Half base end part, 42 Insertion groove, 42B Bottom surface, 42F Flat surface, 42H Insertion part, 42S Side wall surface, 44 Boss, 46 Recess, 50 Insertion part, 54 Large diameter part, 58 Locking part, 62 Inner contact part, 64 Outer contact part, 70 Concave space

Claims

1. A pair of tubes having a pair of parallel tubes that expand and contract by the pressure of a fluid, A sleeve that covers the outer peripheral surfaces of the pair of tubes and expands in the radial direction while restricting the axial elongation of the tubes due to the expansion of the tubes, An insertion portion pair having insertion portions into which the axial ends of the tubes of the tube pair are respectively inserted, and a sealing member that seals the ends of the respective tubes, A restraint member provided from one axial end side to the other end side of the tube pair and sandwiched between opposing portions where the respective tubes face each other, A caulking member that fixes the tube pair to the insertion portion pair from the outside of the sleeve, A filler that is disposed in a concave space on the outer periphery of the insertion portion pair across the opposing portion as viewed from the axial direction, and contacts the tube pair and the sleeve to fill the gap, A fluid pressure actuator comprising the above.

2. The filler has a length that covers from one end to the other end of the insertion portion pair in the axial direction, The fluid pressure actuator according to claim 1.

3. The contact portion of the filler that contacts the insertion portion through the tube follows the shape of the insertion portion, The fluid pressure actuator according to claim 2.

4. The filler is deformed following the shape of the insertion portion pair by the pressing from the outside of the sleeve of the caulking member, The fluid pressure actuator according to claim 2.

5. A pair of tubes having a pair of parallel tubes that expand and contract by the pressure of a fluid, and an insertion portion pair having insertion portions into which the axial ends of the tubes of the tube pair are respectively inserted, the insertion portion pair being formed by a sealing member that seals the ends of the tube pair, and a procedure for inserting into the insertion portion pair, A procedure of providing a restraining member to an opposing portion where the respective tubes face each other from one axial end side to the other end side of the tube pair; A procedure of disposing a filling material in a concave space on the outer periphery of the insertion portion pair across the opposing portion as viewed from the axial direction; A procedure of covering the outer peripheral surface of the tube pair with a sleeve which is a stretchable structure in which a fiber cord oriented in a predetermined direction is woven; A procedure of filling a gap between the tube pair and the sleeve with the filling material while fixing the tube pair to the insertion portion pair using a caulking member from the outside of the sleeve; A method for manufacturing a fluid pressure actuator, comprising the above.

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