Diaphragm structure and diaphragm cylinder

Abstract

To provide a diaphragm structure in which abrasion powder hardly generates on a peripheral face of a shaft body, in comparison with a constitution in which the shaft body is not rotated in a circumferential direction by fitting a pin over both grooves respectively formed on the peripheral face of the shaft body and a peripheral face of a hole of a support body.SOLUTION: A diaphragm structure 100 includes a diaphragm 20, a shaft body 50 fixed to a center of the diaphragm 20, and a support body 32 provided with a hole 32A formed along an axial direction of the shaft body 50, and supporting the shaft body 50 in a manner that the shaft body 50 is movable along an axial direction by fitting a part of the shaft body 50 to the inside of the hole 32A. A shape of a part 52 of the shaft body observed from the axial direction is a shape excluding a complete round, in which a longest distance and a shortest distance from the center of the diaphragm 20 to an outer periphery are different, and a face of a part of the peripheral face of the hole 32A is opposed to a face of a part 32A of the shaft body at a position where a distance from the center is shorter than the longest distance and longer than the shortest distance.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a diaphragm structure and a diaphragm-type cylinder. [Background technology]

[0002] As shown in FIG. 1, claim 1, etc., Patent Document 1 discloses a diaphragm cylinder including: (1) a cylinder body 13 in which a spring chamber 17 and a pressurizing chamber 19 are formed and which is fitted with a diaphragm 16 that separates the spring chamber 17 from the pressurizing chamber 19; (2) a main shaft 22 that is fixed to the diaphragm 16, penetrates the spring chamber 17, and protrudes to the outside of the cylinder body 13; (3) a guide pin 36 that is fixed to the cylinder body 13, engages with a guide groove 35 formed in the main shaft 22, and guides the linear movement of the main shaft 22; (4) a conical coil spring 27 that is fitted to the outside of the main shaft 22 and applies a centripetal force to the main shaft 22 while also applying a spring force in the backward direction; and (5) an advancement-side stopper 32 that is attached to the main shaft 22 and restricts the advance limit position of the main shaft 22 by the fluid supplied to the pressurizing chamber 19. According to Patent Document 1, this diaphragm cylinder is capable of improving the durability of the diaphragm by preventing the diaphragm from bending or tilting. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-304131 Summary of the Invention [Problem to be solved by the invention]

[0004] The diaphragm cylinder disclosed in Patent Document 1 suppresses the rotation of the main shaft 22 around its axis by engaging a guide pin 36 fixed to the cylinder body 13 with a guide groove 35 formed in the main shaft 22 (see FIG. 1 of Patent Document 1). Therefore, when the main shaft 22 reciprocates in the axial direction, the guide pin 36 is pressed against the surface forming the guide groove 35. From another perspective, when the main shaft 22 reciprocates in the axial direction, the rotational force from the main shaft 22, which tends to rotate around its axis, is concentrated on the linear portion of the guide pin 36 that contacts the surface forming the guide groove 35. As a result, wear debris is generated between the guide pin 36 and the surface forming the guide groove 35, and the wear debris remains in the gap between the main shaft 22 and the guide groove 25. The amount of wear debris present in this gap increases with the length of use of the diaphragm cylinder. Due to this mechanism, if a certain amount of wear debris remains in the gap between the main shaft 22 and the guide groove 25, the axial movement of the main shaft 22 may become unstable.

[0005] One of the objects of the present invention is to provide a diaphragm structure that is less likely to generate wear powder on the circumferential surface of the shaft body, compared to a configuration in which grooves are formed on the circumferential surface of the shaft body and on the circumferential surface facing the circumferential surface of the shaft body in the hole of the support body, and a pin is fitted into both grooves, preventing the shaft body from rotating circumferentially. [Means for solving the problem]

[0006] The diaphragm structure of the first embodiment is A diaphragm and a shaft fixed to the center of the diaphragm; a support body to which the peripheral edge of the diaphragm is fixed, a hole formed along the axial direction of the shaft body, a part of the shaft body fitted inside the hole, and supporting the shaft body so that the shaft body is movable along the axial direction; Equipped with a shape of a portion of the shaft body as viewed in the axial direction is other than a perfect circle, with the longest distance from the center of the diaphragm to the outer periphery being a distance D1 and the shortest distance being a distance D2; A portion of the peripheral surface of the hole faces a portion of the surface of the shaft at a position closer to the center than a distance D1 and farther from the center than a distance D2.

[0007] The diaphragm structure of the second embodiment is A diaphragm structure according to a first embodiment, An orthogonal line that is perpendicular to a straight line connecting the center of the diaphragm and the shortest point that is a distance D2 from the center of the diaphragm when viewed from the axial direction, and the orthogonal line that includes the shortest point includes the longest point on the outer periphery of a portion of the shaft that is a distance D1 from the center of the diaphragm when viewed from the axial direction.

[0008] The diaphragm structure of the third embodiment is The diaphragm structure of the first or second aspect, The outer periphery of a portion of the shaft includes at least one first flat surface, the shortest point exists on any one of the at least one first plane, A part of the peripheral surface of the hole is at least one or more second flat surfaces that face the at least one or more first flat surfaces.

[0009] The diaphragm structure of the fourth embodiment is A diaphragm structure according to a third embodiment, A part of the shaft body has a polygonal shape when viewed from the axial direction.

[0010] The diaphragm structure of the fifth embodiment is A diaphragm structure according to a fourth embodiment, The shape of a portion of the shaft body when viewed from the axial direction is a regular polygon.

[0011] The diaphragm structure of the sixth aspect is The diaphragm structure of the fourth or fifth aspect, The portions of the peripheral surface of the hole that face the corners of the shaft face the corners at positions farther than a distance D1 from the center of the diaphragm.

[0012] The diaphragm structure of the seventh aspect is A diaphragm structure according to a first embodiment, When viewed from the axial direction, the intersection of (1) a first orthogonal line perpendicular to a line connecting the center of the diaphragm and the shortest point at a distance D2 from the center of the diaphragm, the first orthogonal line including the shortest point, and (2) a second orthogonal line perpendicular to a line connecting the center of the diaphragm and the longest point at a distance D1 from the center of the diaphragm, the second orthogonal line including the longest point, is located outside a portion of the shaft body when viewed from the axial direction.

[0013] The diaphragm structure of the eighth aspect is A diaphragm structure according to a first embodiment, When viewed from the axial direction, the intersection of (1) an orthogonal line that is perpendicular to a line connecting the center of the diaphragm and the shortest point that is a distance D2 from the center of the diaphragm and that includes the shortest point, and (2) a line connecting the center of the diaphragm and the longest point that is a distance D1 from the center of the diaphragm, is located outside a portion of the shaft body when viewed from the axial direction.

[0014] The diaphragm structure of the ninth aspect is The diaphragm structure of the seventh or eighth aspect, The outer periphery of a portion of the shaft includes at least one first flat surface, the shortest point exists on any one of the at least one first plane, A part of the peripheral surface of the hole is at least one or more second flat surfaces that face the at least one or more first flat surfaces.

[0015] The diaphragm structure of the tenth aspect is A diaphragm structure according to a ninth aspect, a part of the shaft body has a polygonal shape when viewed from the axial direction, the at least one first plane is a plurality of first planes, an outer periphery of a portion of the shaft body is formed by the plurality of first flat surfaces and a plurality of curved surfaces, The plurality of first flat surfaces and the plurality of curved surfaces are arranged alternately in the circumferential direction of the shaft body.

[0016] The diaphragm structure of the eleventh aspect is A diaphragm structure according to a seventh aspect, At least a portion of the shaft body as viewed in the axial direction is a part of an ellipse described by two foci located inside the shaft body, At least a portion of the peripheral surface of the hole is another curved surface opposite to the curved surface corresponding to a portion of the ellipse in a portion of the shaft body, and is another curved surface corresponding to another ellipse drawn by the two foci when viewed from the axial direction.

[0017] The diaphragm structure of the twelfth embodiment is A diaphragm structure according to any one of the first to eleventh aspects, a coil spring disposed between the support body and the diaphragm and pressing the diaphragm from the concave side of the diaphragm; Equipped with.

[0018] The diaphragm type cylinder of the first aspect is A diaphragm structure according to any one of the first to twelfth aspects; a housing that is disposed on the opposite side of the support body with the diaphragm interposed therebetween, the housing having a first through-hole formed in a portion that overlaps with the center of the diaphragm when viewed from the axial direction, the housing gripping the periphery of the diaphragm together with the support body and forming a first space together with the diaphragm; Equipped with the support body forms a second space together with the diaphragm, A second through-hole is formed in the center of the diaphragm, The shaft penetrates the diaphragm through the second through hole and the housing through the first through hole, and moves in the axial direction as the diaphragm deforms due to pressure changes inside the first space or the second space.

[0019] The diaphragm type cylinder of the second aspect is The diaphragm-type cylinder of the first embodiment, the diaphragm has a main body having the second through hole formed at its center, and a penetrating member fixed to a portion of the main body where the second through hole is formed, The diaphragm is fixed to the shaft body via the penetrating member and is detachable from the shaft body.

[0020] The diaphragm type cylinder of the third aspect is A diaphragm-type cylinder according to a second embodiment, the shaft body includes a first shaft body supported by the support body, and a second shaft body detachably fixed to the first shaft body and penetrating the housing through the first through-hole, The penetrating member is sandwiched and gripped by the first shaft body and the second shaft body from both sides in the axial direction. [Effects of the Invention]

[0021] The diaphragm structure of the first embodiment is less likely to generate wear powder on the circumferential surface of the shaft body than a configuration (hereinafter referred to as the comparative configuration) in which grooves are formed on the circumferential surface of the shaft body and on the circumferential surface facing the circumferential surface of the shaft body in the hole of the support body, and a pin is fitted into both grooves to prevent the shaft body from rotating circumferentially.

[0022] The diaphragm structure of the second aspect is less likely to generate wear powder on the circumferential surface of the shaft than the comparative structure.

[0023] The diaphragm structure of the third aspect is less likely to generate wear powder on the circumferential surface of the shaft than a configuration in which the shortest point is on a spherical surface.

[0024] The diaphragm structure of the fourth aspect is less likely to generate wear powder on the circumferential surface of the shaft body than a configuration in which part of the shaft body has an elliptical shape when viewed in the axial direction.

[0025] The diaphragm structure of the fifth aspect can stabilize the reciprocating movement of the shaft body compared to a configuration in which the shape of part of the shaft body when viewed in the axial direction is a polygon other than a regular polygon.

[0026] In the diaphragm structure of the sixth aspect, compared to a configuration in which the portions of the peripheral surface of the hole that face the multiple corners of the shaft face the multiple corners at positions that are a distance D1 from the center of the diaphragm, contact of each corner with the peripheral surface of the hole is suppressed even if the cross section of the shaft is polygonal.As a result, the diaphragm structure of the sixth aspect is less likely to generate wear powder on the peripheral surface of the shaft, even though the cross section of the shaft is polygonal.

[0027] The diaphragm structures of the seventh and eighth aspects are less likely to generate wear powder on the circumferential surface of the shaft than structures other than these.

[0028] The diaphragm structure of the ninth aspect is less likely to generate wear powder on the circumferential surface of the shaft than a structure in which the shortest point is on a spherical surface.

[0029] The diaphragm structures of the tenth and eleventh aspects are less likely to generate wear powder on the circumferential surface of the shaft than structures in which part of the shaft is polygonal when viewed in the axial direction.

[0030] The diaphragm structure of the twelfth embodiment allows the shaft to smoothly reciprocate in response to the spring force of the coil spring for a longer period of time than the comparative configuration.

[0031] The diaphragm type cylinder of the first aspect can achieve smoother axial movement of the shaft in accordance with deformation of the diaphragm for a longer period of time than the diaphragm type cylinder having the comparative configuration.

[0032] The diaphragm type cylinder of the second aspect can extend the period before the diaphragm needs to be replaced compared to the diaphragm type cylinder having the comparative configuration.

[0033] The diaphragm type cylinder of the third aspect has a simple structure and allows the diaphragm to be attached and detached from the shaft body. [Brief explanation of the drawings]

[0034] [Figure 1] 1 is a perspective view of a diaphragm-type cylinder according to an embodiment of the present invention (hereinafter referred to as the present embodiment). FIG. [Figure 2] FIG. 2 is a diagram of the diaphragm-type cylinder of the present embodiment, and is a partially enlarged view of the longitudinal cross section taken along the line II-II in FIG. 1. [Figure 3] FIG. 3 is a cross-sectional view of the diaphragm-type cylinder of the present embodiment taken along the line III-III in FIG. 2. [Figure 4] 3 is a longitudinal cross-sectional view of the diaphragm-type cylinder of the present embodiment when the diaphragm is deformed into a shape different from that in FIG. 2. FIG. [Figure 5] 4 is a view (partially enlarged cross-sectional view) of a portion of a diaphragm-type cylinder according to a first modified example, which corresponds to FIG. 3. FIG. [Figure 6] 4 is a view (partially enlarged cross-sectional view) of a portion of a diaphragm-type cylinder according to a second modified example, which corresponds to FIG. 3. FIG. [Figure 7] 10 is a view (partially enlarged cross-sectional view) of a portion of a diaphragm-type cylinder according to a third modified example, which corresponds to FIG. 3. FIG. [Figure 8] 10 is a view (partially enlarged cross-sectional view) of a portion of a diaphragm-type cylinder according to a fourth modified example, which corresponds to FIG. 3. FIG. [Figure 9] 10 is a view (partially enlarged cross-sectional view) of a portion of a diaphragm-type cylinder according to a fifth modified example, which corresponds to FIG. 3. FIG. [Figure 10] 10 is a view (partially enlarged cross-sectional view) of a portion of a diaphragm-type cylinder according to a sixth modified example, which corresponds to FIG. 3. FIG. [Figure 11] 4A and 4B are views (partially enlarged cross-sectional views) of a portion corresponding to FIG. 3, showing several modified examples of the first rod portion as viewed from the axial direction. [Figure 12] FIG. 10 is a supplementary diagram of the fifth and sixth modified examples. [Figure 13] 10 is a view (partially enlarged cross-sectional view) of a portion corresponding to FIG. 3 in the diaphragm-type cylinders of seventh to ninth modified examples. [Figure 14] FIG. 1 is a longitudinal sectional view of a diaphragm pump according to an application example. DETAILED DESCRIPTION OF THE INVENTION

[0035] Overview Hereinafter, the present embodiment, several modified examples of the present embodiment, and several application examples will be described. First, the present embodiment will be described. Then, several modified examples and several application examples will be described. Please note that in this specification, components having similar functions are denoted by the same or similar reference numerals in each drawing referred to in different embodiments, etc.

[0036] <<Present Embodiment>> The functions, configuration, operation, and effects of this embodiment will be described below in the order of description with reference to the drawings.

[0037] <Function and configuration of the diaphragm-type cylinder of this embodiment> Fig. 1 is a perspective view of a diaphragm type cylinder 10 of this embodiment. Fig. 2 is a view of the diaphragm type cylinder 10, and is a partially enlarged view of the longitudinal section taken along the II-II cutting line in Fig. 1. Fig. 3 is a transverse section of the diaphragm type cylinder 10 taken along the III-III cutting line in Fig. 2. Fig. 4 is a longitudinal section of the diaphragm type cylinder 10 when the diaphragm 20 has deformed into a shape different from that in Fig. 2.

[0038] As shown in Fig. 2, the diaphragm-type cylinder 10 includes a diaphragm 20, a housing 30, an O-ring OR, a coil spring 40, a disk-shaped plate 45, and a rod 50 (an example of a shaft). The diaphragm-type cylinder 10 has a function of deforming the diaphragm 20 with air injected from an external device (one example is a control device (not shown) and a compressor (not shown) controlled by the control device), causing the rod 50 to reciprocate within a predetermined range in the axial direction relative to the housing 30. In this embodiment, a structure including at least the diaphragm 20, the rod 50, and a portion of a first housing 32 (described later) where a through-hole 32A is formed is referred to as a diaphragm structure 100.

[0039] [Diaphragm] The diaphragm 20 has a function of moving the rod 50 along its axial direction (the direction along the axis indicated by the symbol CL in the drawing) by deforming. As shown in FIG. 2, the diaphragm 20 includes, for example, a main body 22 and a central cylinder 23. The main body 22 is a rectangular, deformable rubber member including a disk-shaped portion 22B, an outer peripheral edge portion 22C (an example of an edge), and a protrusion 22D. A through-hole 22A (an example of a second through-hole) is formed in the center of the disk-shaped portion 22B. The protrusion 22D connects the disk-shaped portion 22B and the outer peripheral edge portion 22C around the entire circumference and protrudes toward one side in the thickness direction. Note that the shape of the main body 22 shown in FIG. 4 is the shape in a substantially natural state, i.e., a state in which the main body 22 is substantially undeformed, while the shape of the main body 22 shown in FIG. 2 is the shape in a state in which the main body 22 is elastically deformed and subjected to tensile stress. As mentioned above, the main body 22 is rectangular as an example, but this is due to the shape of the housing 30. Therefore, it should be noted that the shape of the main body 22 may be circular or other shapes depending on the shape, structure, etc. of the housing 30 that grips the main body 22. The central tube 23 has a ring member 24 and a cylindrical member 25. Here, the central tube 23 is an example of a penetrating member, and the ring member 24 is another example of a penetrating member. The ring member 24 is a ring-shaped member with a through-hole 24A (another example of a second through-hole) formed in the center, and is fixed to the center portion of the main body 22, i.e., the portion where the through-hole 24A is formed. The ring member 24 is made of metal, for example. Note that, as shown in FIGS. 2 and 4, the outer diameter of the ring member 24 is set to be larger than the width of the first rod portion 52 and the diameter of the second cylindrical portion 54B, which will be described later. As shown in FIGS. 2 and 4, the cylindrical member 25 is a tube that protrudes in the axial direction from the ring member 24. Specifically, the cylindrical member 25 is arranged along the axial direction around the axis CL and protrudes toward the second rod portion 54 in the axial direction (relative to the first rod portion 52). The through hole 25A of the cylindrical member 25 has a larger diameter than the through hole 24A of the ring member 24. Therefore, a step is formed between the cylindrical member 25 and the ring member 24. As shown in FIGS. 2 and 4, the cylindrical member 25 supports the rod 50 by bringing its outer circumferential surface into contact with the circumferential surface that forms the second through hole 34A in the second housing 34 and bringing its inner circumferential surface into contact with the outer circumferential surface of the rod 50 (specifically, the outer circumferential surface of the second cylindrical portion 54B, which will be described later) to support the rod 50. As shown in FIGS. 2 and 4, the diaphragm 20 fixes a rod 50 that passes through the through-holes 22A and 24A via the ring member 24. In other words, the rod 50 is fixed to the center of the diaphragm 20. More specifically, the axis of the rod 50 and the axis of the diaphragm 20 are the same. The symbol CL in each drawing indicates the axis of the rod 50. It should be noted that in the description herein, the term "axial direction" refers to the direction along the axis of the rod 50.

[0040] [Housing and O-ring] The housing 30 has the functions of accommodating the diaphragm 20 and part of the rod 50 therein, forming a pressurized space for deforming the diaphragm 20, and supporting the rod 50 so that the rod 50 can move along the axial direction. As shown in Fig. 1, the housing 30 is a three-dimensional object that is rectangular when viewed in the axial direction and has a thickness (or height) that is thinner (or shorter) than the length of one side when viewed in the axial direction. As shown in Figs. 1, 2, and 4, the housing 30 has a first housing 32 (an example of a support) and a second housing 34 (an example of a case). The first housing 32 is disposed at one end in the axial direction, and the second housing 34 is disposed opposite the first housing 32 at the other end in the axial direction.

[0041] (1st housing) The first housing 32 has a through-hole 32A (one example of a hole) formed in its center when viewed in the axial direction (see FIGS. 1, 2, and 4). A circular recess 32B is formed in the surface of the first housing 32 facing the second housing 34, surrounding the through-hole 32A. The first housing 32 also has a through-hole OH1 that penetrates from its outer circumferential surface to the recess 32B. A portion of the rod 50 is fitted inside the through-hole 32A. The outer peripheral edge portion 22C of the diaphragm 20 (main body 22) is disposed outside the recess 32B in the first housing 32, and the first housing 32 and the second housing 34 grip the outer peripheral edge portion 22C to fix the outer peripheral edge portion 22C. With the above-described configuration, the first housing 32 forms a space R1 (an example of a second space) surrounded by the diaphragm 20 and the rod 50. As described above, a portion of the rod 50 is fitted inside the through hole 32A. As shown in FIG. 3, the through hole 32A has a rectangular inner peripheral surface when viewed in the axial direction. The first housing 32 allows the rod 50 fitted in the through hole 32A to move along the axial direction in relation to the shape of the peripheral surface of the rod 50, which will be described later. That is, the through hole 32A in the first housing 32 functions as a plain bearing for the rod 50, which moves back and forth in the axial direction. However, the first housing 32 does not simply function as a plain bearing; it supports the rod 50 so that the rod 50 cannot rotate, or is almost unable to rotate, around its axis.

[0042] (Second housing and O-ring) As shown in FIGS. 1, 2, and 4, the second housing 34 is disposed on the opposite side of the first housing 32 with the diaphragm 20 interposed therebetween. A through-hole 34A (an example of a first through-hole) is formed in the second housing 34 at its center as viewed in the axial direction and in a portion that overlaps with the center of the diaphragm 20 as viewed in the axial direction. Furthermore, an endless circumferential groove 34C is formed around the entire circumferential surface of the second housing 34 that forms the through-hole 34A. An O-ring OR is fitted into the circumferential groove 34C. The O-ring OR is compressed and deformed while sandwiched between the cylindrical member 25 and the second housing 34, and functions to block the gap between the cylindrical member 25 and the second housing 34 in the axial direction. A circular recess 34B is formed on the surface of the second housing 34 facing the first housing 32, surrounding the through-hole 34A. Furthermore, a through-hole OH2 is formed in the second housing 34, penetrating from its outer circumferential surface to the recess 34B. The cylindrical member 25 of the central cylinder 23 and a part of the rod 50 arranged inside the cylindrical member 25 are fitted inside the through-hole 34A. The outer peripheral edge portion 22C of the diaphragm 20 (main body 22) is arranged outside the recess 34B in the second housing 34, and the second housing 34 and the first housing 32 fix the outer peripheral edge portion 22C. With the above-described configuration, the second housing 34 forms a space R2 (an example of a first space) surrounded by the diaphragm 20 and the rod 50. The through hole 34A in the second housing 34 functions as a sliding bearing for the rod 50 that reciprocates in the axial direction. The through hole OH2 is also connected to the external device described above, and functions as an air supply port for supplying compressed air from the external device to the space R2.

[0043] [Coil springs and disc-shaped plates] 2 and 4, the coil spring 40 is disposed in the space R1 along the axial direction, that is, disposed between the first housing 32 and the diaphragm 20, and has the function of applying pressure to the diaphragm 20 from the concave side of the main body 22. Here, the coil spring 40 shown in FIG. 2 is in a state where it is slightly compressed from its natural length, and the coil spring 40 shown in FIG. 4 is in a state where it is compressed further than the coil spring 40 shown in FIG. 2. Furthermore, disk-shaped plate 45 has disk 45A that penetrates the center in the thickness direction and ring-shaped peripheral wall 45B on the periphery of disk 45A. In the above description, coil spring 40 is disposed between first housing 32 and diaphragm 20, and applies pressure to diaphragm 20 from the concave side of main body 22. However, in this embodiment, coil spring 40 does not function by contacting main body 22, but rather coil spring 40 is configured to sandwich disk-shaped plate 45 between itself and main body 22, in other words, to function via disk-shaped plate 45.

[0044] 〔rod〕 The rod 50 has the function of moving in the axial direction in accordance with the deformation of the diaphragm 20 (see FIGS. 2 and 4). As shown in FIGS. 2 and 4, the rod 50 has a first rod portion 52 (a part of the shaft and an example of the first shaft), a second rod portion 54 (an example of the second shaft), and a screw 56. The first rod portion 52 and the second rod portion 54 are aligned along the axial direction and are connected by the screw 56, for example.

[0045] 2 and 4, the first rod portion 52 is a portion of the rod 50 that is supported by the first housing 32. From another perspective, the first rod portion 52 is fitted into the through-hole 32A of the first housing 32 and is supported by the first housing 32 so that the rod 50 is movable in the axial direction. For this reason, the length of the first rod portion 52 is designed to be longer than the length (or depth) of the through-hole 32A (see FIGS. 2 and 4). In this embodiment, the first rod portion 52 is rectangular (square) when viewed in the axial direction, as shown in Fig. 3. The first rod portion 52 has the same rectangular cross section at each position from one end to the other in the axial direction (see Figs. 2 and 3). Therefore, the first rod portion 52 is prismatic, as an example. Furthermore, the first rod portion 52 has a through-hole (not shown) centered on the axis.

[0046] The second rod portion 54 has a first cylindrical portion 54A and a second cylindrical portion 54B. The first cylindrical portion 54A has a diameter smaller than the width of the first rod portion 52. The first cylindrical portion 54A has a female thread (not shown) centered on the axis. The second cylindrical portion 54B is, for example, formed integrally with the first cylindrical portion 54A and has a diameter larger than that of the first cylindrical portion 54A. The second cylindrical portion 54B is fitted into the through-hole 34A of the second housing 34 and is supported by the second housing 34 so that the rod 50 is movable in the axial direction. Therefore, the length of the second cylindrical portion 54B is longer than the length (or depth) of the through-hole 34A (see FIGS. 2 and 4).

[0047] 2 and 4, the screw 56 has its head positioned on the opposite side of the second rod portion 54 across the first rod portion 52, and its neck (male thread portion) passes through a through-hole (not shown) in the first rod portion 52 and is tightened by a female thread (not shown) in the first cylindrical portion 54A. Therefore, the second rod portion 54 is detachably fixed to the first rod portion 52. Also, as shown in FIGS. 2 and 4, the first rod portion 52, the first cylindrical portion 54A, and the second cylindrical portion 54B are lined up in the axial direction in this order, and the first cylindrical portion 54A forms a step portion connecting the first rod portion 52 and the second cylindrical portion 54B. The rod 50 has its first cylindrical portion 54A passing through the through hole 24A of the ring member 24 of the diaphragm 20, and the first rod portion 52 and the second cylindrical portion 54B of the second rod portion 54 clamp the ring member 24 from both sides in the axial direction to hold the ring member 24. In this embodiment, when the male thread portion of the screw 56 is tightened by the female thread (not shown) of the first cylindrical portion 54A, the first rod portion 52 and the second cylindrical portion 54B press against the ring member 24 from both sides in the axial direction of the ring member 24. Therefore, in this embodiment, the rod 50 is fixed to the center of the ring member 24 (diaphragm 20).

[0048] <Relationship between the rod and the first housing> Up to this point, each component of this embodiment has been described separately, but below, the relationship between the rod 50 (particularly the first rod portion 52) and the through-hole 32A of the first housing 32 will be described.

[0049] As described above, the shape of the first rod portion 52 of the rod 50 as viewed in the axial direction is, for example, a rectangle (a polygon, specifically a square, which is an example of a regular polygon) (see FIG. 3). That is, the shape of the first rod portion 52 as viewed in the axial direction is a shape other than a perfect circle. Furthermore, the center (axis) of the diaphragm 20 and the center O (axis) of the first rod portion 52 overlap in the axial direction. Here, as shown in FIG. 3, the longest distance from the center O to the outer periphery of the first rod portion 52 is defined as distance D1, and the shortest distance is defined as distance D2. 3, when viewed from the axial direction, the through hole 32A of the first housing 32 is composed of four curved surfaces corresponding to the four relief holes 32A1 required for processing at the four corners and four straight lines corresponding to the four flat surfaces 34A2 connecting the relief holes 32A1. That is, the through hole 32A of the first housing 32 is composed of a plurality of curved surfaces corresponding to the plurality of (four in this embodiment) relief holes 32A1 and a plurality of (four in this embodiment) flat surfaces 32A2 (an example of a second flat surface) connecting the relief holes 32A1. Here, as shown in Figure 3, most of the four planes 32A2 on the circumferential surface of the through hole 32A from the center O, i.e., most of the surfaces on the circumferential surface of the through hole 32A, face the circumferential surface 52A of the first rod portion 52 (an example of the first plane; in this embodiment, the circumferential surface 52A is four planes) at a position closer to the center O than distance D1 and farther than distance D2 (for example, the position of distance D3 in Figure 3). The first housing 32 of this embodiment satisfies the above relationship (hereinafter referred to as the "first relationship between the rod 50 of this embodiment and the through hole 32A"), and supports the rod 50 by fitting the first rod portion 52 into the through hole 32A so that the rod 50 can move along the axial direction.

[0050] Furthermore, instead of the above-described first relationship, another relationship as shown below may be satisfied. Specifically, as shown in FIG. 3, when viewed in the axial direction, the first rod portion 52 has an intersecting plane that intersects with an imaginary circle VC that is centered at the center O and has a radius that is less than the distance D1 and greater than the distance D2. Furthermore, the through hole 32A includes an opposing surface that intersects with the imaginary circle VC and faces the intersecting plane of the first rod portion 52. That is, the other conditions are: (1) the first rod portion 52 has a shape other than a perfect circle when viewed in the axial direction and has the above-described intersecting plane, and (2) the through hole 32A includes an opposing surface that faces the above-described intersecting plane (hereinafter referred to as the "second relationship between the rod 50 and the through hole 32A of this embodiment").

[0051] The above is a description of the function and configuration of the diaphragm type cylinder 10 of this embodiment.

[0052] <Operation of the diaphragm-type cylinder of this embodiment> Next, the operation of the diaphragm type cylinder 10 of this embodiment will be described with reference to FIGS. First, an external device (not shown) is operated, for example, by pulse-controlling the compressed air supplied from a compressor, whereby compressed air is intermittently injected into the space R2 through the through-hole OH2 functioning as an air supply port. In this case, when compressed air is injected into the space R2 of the diaphragm-type cylinder 10 in the state shown in FIG. 2 through the through-hole OH2, the air pressure inside the space R2 increases, and the diaphragm 20 (main body 22) is pressurized. The diaphragm 20 gradually deforms as the pressure increases, compressing the coil spring 40. As a result, the diaphragm-type cylinder 10 changes from the state shown in FIG. 2 to the state shown in FIG. 4. That is, the rod 50 moves from a position where the ring member 24 contacts the second housing 34 to a position where it contacts the first housing 32. Note that when the diaphragm 20 deforms as compressed air is injected into the space R2 through the through-hole OH2, and the volume of the space R2 increases, the volume of the space R1 decreases by the same amount because the air inside the space R1 is exhausted to the outside through the through-hole OH1. Next, when the supply of compressed air from the compressor of the external device is stopped, the through-hole OH2 is opened to the atmosphere, and the air inside the space R2 is discharged to the outside through the through-hole OH2, while external air is injected into the space R1 through the through-hole OH1. Accordingly, the diaphragm 20 (main body 22), which had been pressurized by the compressed air inside the space R2, is released from the pressure, and the coil spring 40, which had been compressed by the diaphragm 20, gradually approaches its natural length. As a result, the diaphragm-type cylinder 10 changes from the state shown in FIG. 4 to the state shown in FIG. 2. In this manner, as the diaphragm 20 deforms due to a change in pressure in the space R1 or the space R2, the rod 50 moves back and forth within a predetermined range in the axial direction. The above is a description of the operation of the diaphragm type cylinder 10 of this embodiment.

[0053] <Effects of this embodiment> The effects of this embodiment will be described below.

[0054] [First effect] As mentioned above, the diaphragm cylinder disclosed in Patent Document 1 (hereinafter referred to as the comparative embodiment) suppresses rotation of the spindle around its axis by engaging a guide pin fixed to the cylinder body with a guide groove formed in the spindle (see Figure 1 of Patent Document 1). Therefore, when the spindle reciprocates in the axial direction, the rotational force from the spindle, which attempts to rotate around its axis, is concentrated on the straight portion of the guide pin that contacts the surface forming the guide groove. As a result, wear debris is generated between the guide pin and the surface forming the guide groove. The amount of wear debris increases with the length of use of this diaphragm cylinder. Furthermore, if a certain amount of wear debris exists in the gap between the spindle and the guide groove, the axial movement of the spindle may become unstable. In contrast, in the diaphragm-type cylinder 10 (and the diaphragm structure 100) of this embodiment, the rod 50 and the through hole 32A of the first housing 32 have the first or second relationship described above. Therefore, when the rod 50 attempts to rotate around its axis during reciprocating axial movement of the rod 50, the circumferential surface 52A of the first rod portion 52 comes into contact with the circumferential surfaces (four flat surfaces 32A2) that constitute the through hole 32A. That is, in this embodiment, the rotational force of the rod 50 is received by the circumferential surface of the through hole 32A, rather than being received by only the linear portion of the guide pin, as in the comparative embodiment described above. Therefore, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment is less likely to generate wear powder on the circumferential surface of the rod 50 (first rod portion 52) than the comparative example.

[0055] [Second effect] For example, even if the peripheral surface of the rod 50 is a curved surface and the through hole 32A is also a curved surface, in other words, even if the curved surfaces are in surface contact with each other (see the sixth variant in Figure 10 described later), this configuration will achieve the first effect described above as long as it has the first or second relationship described above. In this embodiment, as shown in FIG. 3 , (1) the circumferential surface 52A of the first rod portion 52 has multiple flat surfaces, and (2) the circumferential surface of the through hole 32A facing each of the multiple flat surfaces is one of the multiple flat surfaces 34A2. Therefore, when the rod 50 attempts to rotate around its axis during reciprocating axial movement, any one of the flat surfaces of the circumferential surface 52A of the first rod portion 52 contacts one of the flat surfaces 32A2 of the through hole 32A that the first rod portion 52 faces. That is, the rod 50 reciprocates through a predetermined axial section while maintaining surface contact with any one of the flat surfaces 32A2. As a result, in this embodiment, the contact area between the rod 50 and the circumferential surface of the through hole 32A during reciprocating movement is larger than in a configuration in which curved surfaces make surface contact with each other. Therefore, in the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment, the rod 50 can move more smoothly than in a configuration in which curved surfaces are in surface contact with each other. Accordingly, a configuration in which flat surfaces are in surface contact with each other is less likely to generate wear powder on the circumferential surface of the rod 50 (first rod portion 52) than in a configuration in which curved surfaces are in surface contact with each other.

[0056] [Third effect] 3, the first rod portion 52 of the rod 50 of this embodiment is a regular polygon (a square in this embodiment) when viewed in the axial direction, and each of the flat surfaces (four flat surfaces in this embodiment) constituting the circumferential surface 52A thereof faces four flat surfaces 32A2 of the through hole 32A, which has a square shape when viewed in the axial direction. That is, in this embodiment, the first rod portion 52 and the through hole 32A form a combination of four pairs of opposing surfaces. As described above, the rod 50 of this embodiment is fixed to the center of the diaphragm 20 (see FIG. 2). The main body 22 constituting the diaphragm 20 is a deformable rubber member, i.e., an elastic member. The rod 50 may rotate slightly around its axis due to the attachment of the main body 22 when it reciprocates within a predetermined range in the axial direction in response to deformation of the diaphragm 20 due to pressure changes in the space R1 or R2 (see FIGS. 2 and 3). In this case, the main body 22 may twist in one direction during the forward movement of the rod 50, and twist in the opposite direction during the backward movement to eliminate the twisting that occurred during the forward movement. Accordingly, the flat surfaces constituting the circumferential surface 52A of the first rod portion 52 and the flat surfaces 32A2 of the through hole 32A, for example, contact each other at pairs of four opposing surfaces during the forward movement, and contact each other at pairs opposite to the pairs during the forward movement during the backward movement. Therefore, the same pairs of rods are less likely to come into contact with each other on the outward and return journeys. In particular, in the present embodiment, the shape of the first rod portion 52 when viewed from the axial direction is a regular polygon, so the contact area between the pairs of rods on the outward journey and the contact area between the pairs of rods on the return journey are the same. In other words, the contact load (magnitude of friction) that the rod 50 receives from the first housing 32 is also the same on the outward journey and the return journey. Therefore, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment has a good balance of reciprocating movement. Accordingly, it can be said that the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment has a long product life.

[0057] [Fourth Effect] 3, the through hole 32A in this embodiment is configured with four relief holes 32A1 required for machining at the four corners and four flat surfaces 32A2 connecting the relief holes 32A1 when viewed in the axial direction. The first rod portion 52 fitted into the through hole 32A has a rectangular (square) shape when viewed in the axial direction. Each of the four corners of the first rod portion 52 is located inside each of the relief holes 32A1. Therefore, even if the rod 50 rotates slightly (by a tolerance) around its axis during reciprocating axial movement, the four corners of the first rod portion 52 do not come into contact with the circumferential surface of the through hole 32A. Therefore, the diaphragm-type cylinder 10 (and diaphragm structure 100) of this embodiment is less likely to generate wear debris on the circumferential surface of the rod 50 (first rod portion 52) than in a case where the four corners of the first rod portion 52 can contact the circumferential surface of the through hole 32A.

[0058] [Fifth Effect] The diaphragm-type cylinder 10 (and the diaphragm structure 100) of this embodiment is provided with a coil spring 40 that is disposed between the first housing 32 and the diaphragm 20 and presses the diaphragm 20 from the concave side of the main body 22. The rod 50 of this embodiment changes its relative position with respect to the housing 30 in accordance with the amount of expansion and contraction of the coil spring 40. As explained in the first effect, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment is less likely to generate wear powder on the circumferential surface of the rod 50 (first rod portion 52) than the comparative example. Therefore, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment can smoothly reciprocate the shaft in response to the spring force of the coil spring for a longer period of time than the comparative embodiment. Accordingly, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment can achieve stable reciprocating movement of the rod 50 for a longer period of time than the comparative embodiment.

[0059] [Sixth Effect] Furthermore, as explained in the fifth effect, the diaphragm-type cylinder 10 (and the diaphragm structure 100) of this embodiment can realize stable reciprocating movement of the rod 50 over the long term, compared to the comparative embodiment. Accordingly, in this embodiment, the main body 22 of the diaphragm 20 can repeat stable deformation over the long term. In other words, from a long-term perspective, the main body 22, which is an elastic body, is less likely to develop a particular habit. Therefore, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment can achieve smooth axial movement of the rod 50 accompanying deformation of the diaphragm 20 (main body 22) for a longer period of time than in the comparative embodiment. Accordingly, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment can shorten the period until the diaphragm 20 (or main body 22) needs to be replaced, compared to the comparative embodiment.

[0060] [Seventh Effect] In the diaphragm-type cylinder 10 (and the diaphragm structure 100) of this embodiment, the first rod portion 52 and the second cylindrical portion 54B of the second rod portion 54 clamp the ring member 24 of the diaphragm 20 from both sides in the axial direction to hold the diaphragm 20. Therefore, the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment has a simple configuration, and the diaphragm 20 can be attached and detached from the rod 50. In other words, it can be said that the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment is easy to maintain.

[0061] [Eighth Effect] The diaphragm-type cylinder 10 (and the diaphragm structure 100) of this embodiment prevents or suppresses rotation of the rod 50 around its axis by the first rod portion 52, which is a part of the rod 50. Furthermore, the through-hole 32A of the first housing 32 into which the first rod portion 52 is fitted is not a recess but passes through the first housing 32. If the through-hole 32A were a recess, the end of the rod 50 on the axial side of the first rod portion 52 could not be used as an acting part (a part that exerts an action such as pushing or pulling) on ​​an object (not shown). Therefore, in the diaphragm type cylinder 10 (and the diaphragm structure 100) of this embodiment, both end portions of the rod 50 can be used as acting portions for pushing an object (not shown), for example. Note that this effect is achieved when the hole formed in first housing 32 is through-hole 32A and excludes the case where the hole is a recess, but the above-mentioned first to seventh effects are achieved even when the hole is a recess. In other words, it should be noted that modified examples in which the hole formed in first housing 32 is a recess rather than a through-hole are also included in the technical scope of the present invention.

[0062] The above is a description of the effects of this embodiment. Also, the above is a description of this embodiment.

[0063] <<Multiple Modifications and Multiple Application Examples>> As described above, one example of the present invention has been described using the above-described embodiment, but the present invention is not limited to this embodiment. The technical scope of the present invention also includes, for example, the multiple modified examples and multiple application examples described below. Furthermore, the technical scope of the present invention also includes, for one of the above-described embodiment and the multiple modified examples described below, (1) a form in which some of the components are replaced with components of another form (not shown), (2) a form in which some or all of the components of another form are added to the components (not shown), and other forms. In other words, the technical scope of the present invention also includes forms in which the technologies disclosed in this specification are combined. The same applies to the multiple application examples described below.

[0064] For example, in this embodiment, the rod 50 has been described as having a first rod portion 52, a second rod portion 54, and a screw 56. It has also been described that when the male threaded portion of the screw 56 is tightened by the female thread of the first cylindrical portion 54A, the first rod portion 52 and the second cylindrical portion 54B are configured to be in pressure contact with each other from both axial sides of the ring member 24. However, it is also possible to provide a male thread on one or the other of the first rod 52 and the second rod 54, and form a female thread on the other or one of the rods, so that they are directly connected. In this case, the screw 56 is not necessary, and the diaphragm-type cylinder 10 can be made more compact by shortening its axial length.

[0065] In addition, in this embodiment, the rod 50 has been described as having the first rod portion 52, the second rod portion 54, and the screw 56. However, these may be configured as an integrated unit.

[0066] In addition, in this embodiment, the first rod portion 52 of the rod 50 has been described as being rectangular when viewed in the axial direction (see FIG. 3). However, like the first rod portion 52D of the diaphragm-type cylinder 10D (and diaphragm structure 100D) of the first modified example shown in FIG. 5, the four corners of the first rod portion 52 may be chamfered to form a plurality of (four, as an example) curved surfaces 52D1. With this configuration, even if there is manufacturing variation or tolerance variation in the rod 50 or the through-hole 32A, the four corners of the rod 50 will never come into contact with the through-hole 32A. Although the first rod portion 52D of this modified example is manufactured by chamfering the four corners of the first rod portion 52, it is also possible to form a plurality (four, for example) of flat surfaces 52D2 (an example of a first flat surface) and a plurality (four, for example) of curved surfaces 52D1 by machining the peripheral surface of a cylinder (not shown), for example. In this way, the rod 50 can be manufactured from a cylinder, and therefore the rod 52D can be provided with high precision and at low cost.

[0067] Furthermore, for example, as in a diaphragm-type cylinder 10E (and a diaphragm structure 100E) of a second modified example shown in FIG. 6, the through hole 32A formed in the first housing 32 of the above-described embodiment may be replaced with a through hole 32E. In this modified example, the through hole 32E as viewed from the axial direction is such that the four straight lines constituting the four planes 32A2 of the above-described embodiment are changed to compound lines 32E1 each consisting of two straight lines and an arc line between the two straight lines that is recessed toward the first rod portion 52. In the case of this modified example, the rod 50 and the through hole 32A of the first housing 32 also have the first or second relationship described in the above-described embodiment. The effects of this modification are similar to those of the above-described embodiment.

[0068] Furthermore, for example, the first rod portion 52 of the above-described embodiment may be replaced with a first rod portion 52F, as in a diaphragm-type cylinder 10F (and diaphragm structure 100F) of a third modified example shown in FIG. 7. In this modified example, the rectangular outer periphery of the first rod portion 52 as viewed from the axial direction in the above-described embodiment (the four straight lines constituting the four planes 32A2) is changed to a compound line with each central portion recessed toward the axis. In this modified example, the rod 50 and the through hole 32A of the first housing 32 also have the first or second relationship described in the above-described embodiment. The effects of this modification are similar to those of the above-described embodiment.

[0069] Furthermore, for example, as in a diaphragm-type cylinder 10G (and a diaphragm structure 100G) of a fourth modified example shown in FIG. 8, the through hole 32A formed in the first housing 32 of the above-described embodiment may be replaced with a through hole 32G. In this modified example, the through hole 32G as viewed from the axial direction is modified such that the four straight lines constituting the four planes 32A2 of the above-described embodiment are replaced with compound lines 32G1 each consisting of two straight lines and an arc line between the two straight lines that protrudes toward the first rod portion 52. Furthermore, the first rod portion 52 of the above-described embodiment is modified to the first rod portion 52F of the second modified example (see FIG. 7). In this modified example, the rod 50 and the through hole 32A of the first housing 32 also have the first or second relationship described in the above-described embodiment. The effects of this modification are similar to those of the above-described embodiment.

[0070] Furthermore, for example, as in a diaphragm-type cylinder 10H (and diaphragm structure 100H) of a fifth modified example shown in FIG. 9, the through hole 32A formed in the first housing 32 of the above-described embodiment may be replaced with a through hole 32H. When viewed from the axial direction, the through hole 32H has a rectangular shape with four curved corners, and when viewed from the axial direction, the first rod portion 3252H also has a rectangular shape with four curved corners. In this modified example, the rod 50 and the through hole 32A of the first housing 32 also have the first or second relationship described in the above-described embodiment. In this modification, there are no corners (ridges) on the outer periphery of the first rod portion 52H or on the through hole 32H, so even if the rod 50H rotates slightly (by about the tolerance) around its axis during reciprocating axial movement of the rod 50H and the first rod portion 52H comes into contact with the circumferential surface of the through hole 32H, there is no possibility of the corners and surfaces coming into contact. The effects of this modification are similar to those of the above-described embodiment.

[0071] Furthermore, for example, as in a diaphragm-type cylinder 10I (and a diaphragm structure 100I) of a sixth modified example shown in FIG. 10 , the through hole 32A formed in the first housing 32 of the above-described embodiment may be replaced with a through hole 32I, and the first rod portion 52 may be replaced with a first rod portion 52I. Specifically, the through hole 32I viewed from the axial direction is a portion surrounded by a compound line formed by superimposing an elongated rectangular through hole and an ellipse. Furthermore, the first rod portion 52I viewed from the axial direction is a portion of an ellipse facing each other along a pair of curved surfaces of the through hole 32I. In this modified example as well, the rod 50 and the through hole 32A of the first housing 32 have the first or second relationship described in the above-described embodiment. In this modified example, a relatively large gap is formed between the through hole 32I and the first rod portion 52I, but the presence of this relatively large gap does not affect the control of the air pressure inside the space R2. In fact, the presence of this relatively large gap makes it possible to eliminate the through hole OH1 of the first housing 32. The effects of this modification are similar to those of the above-described embodiment.

[0072] In this embodiment, the shape of the first rod portion 52 of the rod 50 as viewed in the axial direction is, for example, square, as shown in Fig. 3. However, as long as the relationship between the shape of the first rod portion 52 as viewed in the axial direction and the first housing 32 satisfies the first or second relationship described above, the shape of the first rod portion 52 as viewed in the axial direction does not have to be square. For example, as shown in Figures 11(a) to 11(h), the shape of the first rod portions 52a to 52h when viewed from the axial direction may be a triangle (equilateral triangle, isosceles triangle, or right-angled triangle), a pentagon, a hexagon, a heptagon, an octagon, a decagon, or any other polygon. Furthermore, in the case of a quadrangle, it may be a rectangle (not shown) instead of a square as in this embodiment. That is, the shape of the first rod portions when viewed from the axial direction may be a regular polygon or a polygon other than a regular polygon, as shown in Figures 11(a) to 11(h). In these cases, the shape of the first rod portion as viewed in the axial direction satisfies any one of the following first, second, and third conditions, assuming the above-mentioned first or second relationship. In other words, the technical scope of the present invention includes all forms that satisfy these conditions. (First condition) The first condition is as follows: "When viewed from the axial direction of the rod 50, an orthogonal line (dotted line L2) perpendicular to a straight line (dashed line L1) connecting the center O of the diaphragm 20 and the shortest point that is a distance D2 from the center of the diaphragm 20, and the orthogonal line (dotted line L2) that includes the shortest point includes the longest point on the outer periphery of a part (first rod portion 52) of the rod 50 that is a distance D1 from the center O when viewed from the axial direction." From this condition, if the rod 50 attempts to rotate around its axis when it moves back and forth in the axial direction, the circumferential surface of the first rod portion 52 will come into contact with the circumferential surface that forms the through hole of the first housing 32. In other words, this condition can be said to be a condition for preventing or suppressing rotation of the rod 50 around its axis when it moves back and forth in the axial direction. 11(a) to 11(h), the shape of the first rod portion when viewed in the axial direction is polygonal, but this condition may be satisfied even if the shape is not polygonal. Furthermore, within the technical scope of the present invention, the shape of the first rod portion when viewed in the axial direction may be a shape other than a polygon. (Second condition) The second condition is as follows: "(1) The outer periphery of a portion of the rod 50 (first rod portion 52) includes at least one or more planes PL (first planes), (2) the shortest point at a distance D2 from the center of the diaphragm 20 is located on one of the at least one or more planes PL, and (3) a portion of the periphery of the through hole of the first housing 32 is at least one or more planes (second planes (not shown)) that face the at least one or more planes PL." From this condition, when the rod 50 moves back and forth in the axial direction, the flat surfaces of the first rod portion 52 and the through-hole of the first housing 32 come into contact with each other. In other words, this condition can be said to be a condition that reduces the contact load during the reciprocating movement of the rod 50 (realizes smooth movement) while preventing or suppressing rotation of the rod 50 about its axis when the rod 50 moves back and forth in the axial direction. (Third condition) The third condition is that the first and second conditions are satisfied.

[0073] Further, the following can be said about the fifth modified example in FIG. 9 and the sixth modified example in FIG. For example, as shown in Figures 12(a) and 12(b), the first rod portion 52H of the fifth modified example in Figure 9 and the first rod portion 50I of the sixth modified example in Figure 10 satisfy the following conditions, assuming the above-mentioned first relationship or second relationship. (Fourth condition) "When viewed from the axial direction of the rod 50, an intersection IP1 between (1) an orthogonal line OL1 (an example of a first orthogonal line) that is perpendicular to a straight line SL1 connecting the center O of the diaphragm 20 to the shortest point at a distance D2 from the center O and that includes the shortest point, and (2) an orthogonal line OL2 (an example of a second orthogonal line) that is perpendicular to a straight line SL2 connecting the center O to the longest point at a distance D1 from the center O and that includes the longest point, exists outside a part (first rod portion 52) of the rod 50 when viewed from the axial direction." This condition can be said to be a condition that provides the effect of the fifth modification of FIG. The first rod portion 52H of the fifth modified example shown in FIG. 9 further satisfies the following condition. (Fifth condition) "When viewed from the axial direction of the rod 50, (1) an orthogonal line OL1 that is perpendicular to a line SL1 connecting the center O of the diaphragm 20 to the shortest point at a distance D2 from the center O, and that includes the shortest point, and (2) an intersection point IP2 of a line SL2 connecting the center O to the longest point at a distance D1 from the center O, exist outside a part of the rod 50 (first rod portion 52) when viewed from the axial direction." This condition can be said to be a condition that provides the effect of the fifth modification of FIG.

[0074] In addition, in the sixth modified example of Figures 10 and 12(b), the first rod portion 52I is an ellipse when viewed from the axial direction, and the through hole 32I formed in the first housing 32 when viewed from the axial direction is described as being the portion surrounded by a composite line that is a long rectangular through hole and an ellipse superimposed on each other. However, the sixth modified example may be further modified, as in the seventh modified example diaphragm-type cylinder 10J (and diaphragm structure 100J) of Figure 13(a), so that the through hole 32I is an ellipse described by the same two foci FP as in the case of the first rod 52I when viewed from the axial direction. 13(b), a portion of the first rod portion 52I when viewed from the axial direction may be a curved surface corresponding to an ellipse, and the remainder may be a surface 52I1 that does not correspond to an ellipse. Also, as in the ninth modified example shown in FIG. 13(c), a portion of the first housing 32J when viewed from the axial direction may be a curved surface corresponding to an ellipse, and the remainder may be a surface 32J1 that does not correspond to an ellipse. Furthermore, although not shown, a configuration in which the eighth modified example and the ninth modified example are combined may be used. The eighth and ninth modifications satisfy the fourth condition described above. The sixth modification and the eighth to ninth modifications can be considered to be embodiments encompassed in the following invention. At least a portion of a shaft body (for example, the first rod 52I) as viewed in the axial direction of the shaft body is a part of an ellipse described by two foci FP located inside the shaft body, At least a portion of the peripheral surface of the hole (for example, the first housing 32I) is another curved surface that faces the curved surface corresponding to a portion of the ellipse in a portion of the shaft body, and is another curved surface corresponding to another ellipse drawn by the two foci when viewed from the axial direction. Diaphragm.

[0075] In addition, in the above-described embodiment and multiple modified examples, the diaphragm structure 100 and the like have been described as constituting a part of the diaphragm cylinder 10 and the like. However, as long as the diaphragm structure 100 and the like has the basic configuration, it may be configured to constitute a part of a device other than the diaphragm cylinder 10, for example. For example, the diaphragm structure 100 and the like may constitute a part of the diaphragm pump 10K of the application example shown in FIG. 14. Although not shown, the diaphragm structure 100 or the like may form part of a pump including a pair of diaphragm pumps 10K that share the rod 50. Furthermore, although not shown, the diaphragm structure 100 and the like may form part of a speaker, a power source, or other device.

[0076] The above is a description of several modified examples and several application examples of this embodiment. [Explanation of symbols]

[0077] 10 Diaphragm type cylinder 100 diaphragm structure 20 diaphragm 22 Main Unit 22A through hole 22B Disk shaped part 22C outer edge 22D protrusion 23 Penetrating member 24 Ring member 24A through hole (another example of the second through hole) 25 Cylinder member 25A through hole 30 Housing 32 First housing (an example of a support) 32A Through hole (example of hole) 32A2 Plane (an example of a second plane) 32B dent 34C circumferential groove 34 Second housing (example of enclosure) 34A through hole 40 Coil spring 45 Disc-shaped plate 45A Disc 45B Peripheral wall 50 Rod (example of shaft) 52 First rod section 52A Peripheral surface (an example of the first plane) 52D First rod section 52D1 Curved surface 52D2 Plane (example of first plane) 54 Second rod section 54A First cylindrical section 54B Second cylindrical section 56 Screw CL axis D1 longest distance D2 Shortest distance OH1 through hole OH2 through hole OL1 Orthogonal line (an example of the first orthogonal line) OL2 Orthogonal line (an example of a second orthogonal line) OR O-ring R1 space (second space) R2 space (second space) VC Virtual Circle

Claims

1. A diaphragm and a shaft fixed to the center of the diaphragm; a support body to which the peripheral edge of the diaphragm is fixed, a hole formed along the axial direction of the shaft body, a part of the shaft body fitted inside the hole, and supporting the shaft body so that the shaft body is movable along the axial direction; Equipped with a shape of a portion of the shaft body as viewed in the axial direction is other than a perfect circle, with the longest distance from the center of the diaphragm to the outer periphery being a distance D1 and the shortest distance being a distance D2; a portion of the peripheral surface of the hole faces a portion of the surface of the shaft body at a position that is closer to the center than a distance D1 and farther from the center than a distance D2; Diaphragm structure.

2. an orthogonal line perpendicular to a straight line connecting the center of the diaphragm and the shortest point at a distance D2 from the center of the diaphragm as viewed from the axial direction, the orthogonal line including the shortest point including a longest point at a distance D1 from the center of the diaphragm on an outer periphery of a part of the shaft as viewed from the axial direction; The diaphragm structure according to claim 1 .

3. an outer periphery of a portion of the shaft body includes at least one first flat surface; the shortest point exists on any one of the at least one or more first planes, a part of the peripheral surface of the hole is at least one or more second flat surfaces opposed to the at least one or more first flat surfaces; The diaphragm structure according to claim 1 or 2.

4. The shape of a portion of the shaft body as viewed from the axial direction is polygonal. The diaphragm structure according to claim 3.

5. The shape of a portion of the shaft body as viewed from the axial direction is a regular polygon. The diaphragm structure according to claim 4.

6. a portion of the peripheral surface of the hole facing the plurality of corners of the shaft body faces the plurality of corners at a position farther than a distance D1 from the center of the diaphragm; The diaphragm structure according to claim 4 or 5.

7. When viewed from the axial direction, an intersection of (1) a first orthogonal line perpendicular to a line connecting the center of the diaphragm and the shortest point at a distance D2 from the center of the diaphragm, the first orthogonal line including the shortest point, and (2) a second orthogonal line perpendicular to a line connecting the center of the diaphragm and the longest point at a distance D1 from the center of the diaphragm, the second orthogonal line including the longest point, exists outside a portion of the shaft when viewed from the axial direction. The diaphragm structure according to claim 1 .

8. When viewed from the axial direction, an intersection of (1) an orthogonal line that is orthogonal to a line connecting the center of the diaphragm and the shortest point that is a distance D2 from the center of the diaphragm, and that includes the shortest point, and (2) a line connecting the center of the diaphragm and the longest point that is a distance D1 from the center of the diaphragm, exists outside a portion of the shaft when viewed from the axial direction. The diaphragm structure according to claim 1 .

9. an outer periphery of a portion of the shaft body includes at least one first flat surface; the shortest point exists on any one of the at least one or more first planes, a part of the peripheral surface of the hole is at least one or more second flat surfaces opposed to the at least one or more first flat surfaces; The diaphragm structure according to claim 7 or 8.

10. a part of the shaft body has a polygonal shape when viewed from the axial direction, the at least one first plane is a plurality of first planes, an outer periphery of a portion of the shaft body is formed by the plurality of first flat surfaces and a plurality of curved surfaces, The plurality of first flat surfaces and the plurality of curved surfaces are arranged alternately in the circumferential direction of the shaft body. The diaphragm structure according to claim 9.

11. At least a portion of the shaft body as viewed in the axial direction is a part of an ellipse described by two foci located inside the shaft body, At least a part of the peripheral surface of the hole is another curved surface opposite to the curved surface corresponding to the part of the ellipse in the part of the shaft body, and is another curved surface corresponding to the other ellipse described by the two foci when viewed from the axial direction. The diaphragm structure according to claim 7.

12. a coil spring disposed between the support body and the diaphragm and pressing the diaphragm from the concave side of the diaphragm; The diaphragm structure according to any one of claims 1 to 11, comprising:

13. A diaphragm structure according to any one of claims 1 to 12; a housing that is disposed on the opposite side of the support body with the diaphragm interposed therebetween, the housing having a first through-hole formed in a portion that overlaps with the center of the diaphragm when viewed from the axial direction, the housing gripping the periphery of the diaphragm together with the support body and forming a first space together with the diaphragm; Equipped with the support body forms a second space together with the diaphragm; A second through hole is formed in the center of the diaphragm, the shaft penetrates the diaphragm through the second through-hole and the housing through the first through-hole, and moves in the axial direction in response to deformation of the diaphragm due to a pressure change inside the first space or the second space. Diaphragm type cylinder.

14. the diaphragm has a main body having the second through hole formed at its center, and a penetrating member fixed to a portion of the main body where the second through hole is formed, The diaphragm is fixed to the shaft body via the penetrating member and is detachable from the shaft body.

14. The diaphragm-type cylinder according to claim 13.

15. the shaft body includes a first shaft body supported by the support body, and a second shaft body detachably fixed to the first shaft body and penetrating the housing through the first through hole, The penetrating member is sandwiched and held by the first shaft body and the second shaft body from both sides in the axial direction.

15. The diaphragm-type cylinder according to claim 14.

Images