Clamping and holding member

Abstract

To provide means, with a simple structure, for sandwiching and holding a holding object remarkably strongly like friction joint without any damage to the holding object.SOLUTION: A clamp-holding member has: a journal part that performs journaling so as to move forward and backward and a holding body that holds, at a fixed position, a receiving part disposed facing the journal part; a pressing body inserted into the journal part, and capable of pressing a holding object by a pressing part facing the receiving part; and an operation part attached to a shaft part disposed on the pressing body, and capable of operating the pressing body forward and backward without requiring rotation. The shaft part is journaled in a non-rotation state by the journal part so as to axially move forward and backward, and the pressing part can press the holding object when moving the shaft part forward.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a clamping and holding member that clamps and holds an object to be held.

Background Art

[0002] Conventionally, as a member for holding two or more objects to be superposed, a screw-type clamp having a pair of opposing arm portions sandwiching an opening is known (see, for example, Patent Document 1). In such a screw-type clamp, a receiving washer is attached to one arm portion of the clamp body, and a fastening bolt is screwed and attached to the other arm portion. A handle is provided at one end portion of the fastening bolt, and the fastening bolt moves in the direction of the receiving washer while rotating by the operation of the handle. Then, the tip portion of the fastening bolt presses the object to be held, and the receiving washer supports the object to be held that is being pressed, and as a result, the object to be held is clamped and pressed. Also, generally, as a method for holding two or more objects to be superposed, a bolt is inserted into a bolt hole penetrating the object to be held, and the bolt is fastened with a nut to clamp the object to be held with the bolt and the nut, and friction joining is widely performed. In such friction joining, the tensile force generated in the bolt is used to press the object to be held.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The screw clamp described in Patent Document 1 described above presses against the object to be held while the fastening bolt rotates, so that the tip of the fastening bolt presses against the object to be held while sliding in contact with it until the object to be held is clamped with sufficient clamping force. In such a case, there is a problem that the surface of the object to be held is scraped by the sliding contact of the fastening bolt, and multiple concentric circular groove-like scratches are easily generated by pressing while sliding in contact, resulting in damage to the object to be held. In addition, since the fastening bolt is screwed into the arm portion, vibration and forces in the direction perpendicular to the axis are transmitted to the fastening bolt through the object to be held, causing axial play. Therefore, even if the tightening is done strongly, once play occurs, the tightened state is easily loosened, and as a result, the object to be held cannot be clamped, which is a problem. Also, in the case of a friction joint where a bolt is inserted through a bolt hole of the object to be held and the object to be held is clamped with a bolt and a nut, processing for providing a bolt hole in the object to be held is required.

[0005] The present invention has been made by the earnest research of the inventor in view of the above problems, and an object thereof is to provide a means for firmly clamping and holding an object to be held without damaging it.

Means for Solving the Problems

[0006] The In one aspect tightening and holding member of the present invention a pressing body, and inserting the pressing body has a shaft support portion that pivotally supports it so as to be able to move forward and backward, and a holding body that holds a receiving portion disposed opposite to the shaft support portion in a fixed position, provided on the pressing body and, facing the receiving portion and a pressing part that can press the object to be held, and an operating portion that is mounted on a shaft portion provided on the pressing body and enables the pressing body to be advanced and retracted without rotation. The shaft portion surrounding to is axially movable forward and backward without rotation by the shaft support portion, form a columnar shape and the pressing portion is characterized in that it can press the object to be held when the shaft portion advances. is pivotally supported so that rotation about an axis is restricted, and by the rotational operation of the operation part The shaft portion it is displaced is axially movable forward and backward without rotation by the shaft support portion,

[0007] The clamping and holding member of the present invention has a first region where the shaft portion is pivotally supported by the shaft support portion and a second region where the operation portion is mounted. The pressing portion is located at the tip of the first region. The first region has a columnar shape that can engage with the shaft support portion in the circumferential direction. The second region has a male screw spiral groove, and the shaft support portion has a hole that engages with the inserted first region in the circumferential direction.

[0008] In the clamping and holding member of the present invention, the first region of the shaft portion has a polygonal, oval, or elliptical cross-sectional shape, and the hole has a shape corresponding to the cross-sectional shape.

[0009] The clamping and holding member of the present invention is characterized in that the first region has a shape with a notch in a part of its circumferential surface, and the hole has an inner circumferential surface that engages with the notched portion of the first region in the circumferential direction.

[0010] The clamping and holding member of the present invention has a first region where the shaft portion has a circular cross-section and is pivotally supported by the shaft support portion and a second region where the operation portion is mounted. The pressing portion is located at the tip of the first region. The second region has a male screw spiral groove formed on its outer circumferential surface and a notch surface formed by notching the male screw spiral groove along the axial direction. The hole has an insertion fitting portion that is arranged at the opening and has a diameter larger than that of the first region. The insertion fitting portion has an engagement surface whose length from the axial center gradually decreases on its inner circumferential surface. An intervening member is inserted into the opening and surrounds the second region. The outer circumferential surface of the intervening member is circumferentially locked to the opening, and the inner circumferential surface is circumferentially locked to the engagement surface.

[0011] The clamping and holding member of the present invention is characterized in that the pressing portion has a concavo-convex surface that abuts against the object to be held.

[0012] The clamping and holding member of the present invention is characterized in that the receiving portion is in surface contact with the object to be held and has a support member that can tilt with respect to the object to be held.

[0013] The clamping and holding member of the present invention is characterized in that the receiving part has a concave part with a spherical or curved bottom surface, the support member has a convex part on a protruding surface along the shape of the bottom surface, and the support member is arranged on the receiving part such that the convex part can be in sliding contact with the concave part.

[0014] The clamping and holding member of the present invention is characterized in that the support member has a concavo-convex contact surface that contacts the object to be held.

[0015] The clamping and holding member of the present invention is characterized in that in the direction along the axis of the shaft portion, the center of the support member and the center of the pressing portion are displaced.

Advantages of the Invention

[0016] According to the present invention, with a simple structure, it is possible to hold the object to be held extremely firmly without damaging the object to be held and in the same manner as frictional joining.

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

Figure 14

Figure 15

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments of the tightening and holding member of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the appearance of the tightening and holding member of the present embodiment, and FIG. 2 is a cross-sectional view showing the tightening and holding member of the present embodiment. The tightening and holding member 1 includes a shaft support portion 2 and a holding body 4 that holds a receiving portion 3 disposed opposite to the shaft support portion 2 in a fixed position so as to form a substantially C shape, G shape, U shape, or V shape.

[0019] Further, the fastening and holding member 1 has a compression friction joining structure. That is, the fastening and holding member 1 arranges a pair of objects to be held between the shaft support portion 2 and the receiving portion 3, the tip of the pressing body 10 (described later) presses the object to be held, and the support member 20 (described later) supports the object to be held. Thereby, the pair of objects to be held are joined by the compressive axial force acting on the pressing body 10, and the structure in which there is no play in the direction perpendicular to the axis of the pressing body 10 with respect to the shaft support portion 2 firmly maintains the friction joining state in which the pressing body 10 presses the object to be held and the support member 20 supports the object to be held.

[0020] The shaft support portion 2 pivotally supports the pressing body 10 so as to be able to advance and retreat. Specifically, it has a hole portion 6 for inserting the pressing body 10 so that the pressing body 10 can be pivotally supported so as to be able to advance and retreat. The pressing body 10 has a shaft portion 12, a pressing portion 14 that can press the object to be held, and an operation portion 16 for enabling the pressing body 10 (shaft portion 12) to be advanced and retreated without rotation.

[0021] FIG. 3 is a perspective view showing the shaft portion 12 of the present embodiment. In the shaft portion 12, a first region 12a that can be inserted into the hole portion 6 from one end side to the middle portion is formed, and a second region 12b to which the operation portion 16 can be attached from the other end side to the middle portion is formed.

[0022] The cross-sectional shape of the first region 12a is set so as to be substantially the same as the hole shape of the hole portion 6. Here, it is set to a hexagonal cross-sectional shape that is locked in the circumferential direction by the inner peripheral surface of the hole portion 6. Note that the cross-sectional shape of the first region 12a may be any shape that can be engaged with the hole portion 6 in the circumferential direction. For example, in addition to a polygonal shape, an elliptical shape, an oval shape, etc., a shape having one or more pairs of two-sided widths, a cross-sectional D shape in which a part of the peripheral surface is cut out, etc. may be used. Of course, since the shape of the hole portion 6 is set to correspond to the cross-sectional shape of the first region 12a, when the first region 12a is set to a hexagonal cross-sectional shape, the shape of the hole portion 6 is preferably set to a hexagonal shape. Note that the cross-sectional shape of the first region 12a and the cross-sectional shape of the hole portion 6 do not necessarily have to match, and the shapes of each may be set so as not to rotate relative to each other during insertion. However, it is desirable to determine the shape and dimensions so that there is no play, an unnecessary amount of clearance, between the first region 12a and the hole portion 6, the outer peripheral surface of the first region 12a is substantially in close contact with the inner peripheral surface of the hole portion 6, and the shaft portion 12 does not rattle in the direction perpendicular to the axis.

[0023] The second region 12b has a male screw spiral groove with a left-handed thread on the outer peripheral surface for arranging the operation portion 16 described later. In addition, the second region 12b is set so that the maximum radius (the crest diameter of the male screw) is smaller than the minimum radius in the first region 12a (for example, the length from the axis to one side in the hexagonal cross-sectional shape). The pressing portion 14 forms the tip of the first region 12a, and the surface that contacts the object to be held is configured in an uneven shape.

[0024] The operation part 16 is a substantially cylindrical member having a female thread portion with a left-handed thread on its inner peripheral surface, and is attached to the shaft portion 12 so as to surround the second region 12b. That is, the operation part 16 is attached to the shaft portion 12 by screwing into the male thread spiral groove of the second region 12b, and further supports the shaft portion 12 so as to be reciprocally movable in the axial direction within the range where the operation part 16 and the second region 12b are screwed together. Thereby, the advance and retreat operation of the shaft portion 12 can be performed by rotating the operation part 16.

[0025] Further, the outer peripheral surface of the operation part 16 is set to a hexagonal shape so that it can be engaged with a fastening tool such as a wrench. Of course, the outer shape may be a structure that can be engaged with a fastening tool such as a multi-sided shape other than a hexagon, a shape having at least one set of two-sided widths formed by two surfaces parallel to each other across the axis, a shape including a plurality of irregularities, etc.

[0026] Also, the axial displacement of the operation part 16 is restricted with respect to the shaft support portion 2. For example, a position restricting cover 18 for fixing the operation part 16 to the shaft support portion 2 is attached. The position restricting cover 18 surrounds the operation part 16 and the shaft portion 12, and axially engages with the operation part 16 to restrict the axial displacement of the operation part 16. That is, the position restricting cover 18 has a substantially cylindrical shape, and has an engaging portion 18a that protrudes radially inward at one end of the inner peripheral surface and axially engages with the operation part 16.

[0027] Also, the position restricting cover 18 is fixed to the shaft support portion 2. Specifically, the position restricting cover 18 has a female thread portion 18b with a right-handed thread on the inner peripheral surface surrounding the shaft support portion 2, and the shaft support portion 2 has a male thread portion that screws into the female thread portion 18b. The position restricting cover 18 is fixed to the shaft support portion 2 by screwing the respective thread portions together.

[0028] The receiving part 3 is tiltably installed with a support member 20 that supports an object to be held, which is pressed by the pressing body 10. Specifically, the receiving part 3 forms a recess 8 on the extension line of the axis of the hole part 6 for tiltably installing the support member 20 with respect to the object to be held. The recess 8 has a bottom surface with a substantially hemispherical shape so that the support member 20 can be in sliding contact. The installation of the support member 20 in the recess 8 can be performed by a fastening member such as a bolt. Therefore, a female screw hole 8a may be formed at the center of the bottom surface of the recess 8. The female screw hole 8a shall be formed on the extension line of the axis of the hole part 6.

[0029] FIG. 4 is a cross-sectional view showing the support member 20 of the present embodiment. The support member 20 has a convex-shaped convex surface portion 22 that fits into the recess 8 and an aspherical contact surface 24 that contacts the object to be held, and further has an insertion hole 26 that penetrates the central portions of the convex surface portion 22 and the contact surface 24. The contact surface 24 is set to have a cross-sectional area such that the shear strength is stronger than the shear strength in the second region. For example, when the cross-sectional area of the contact surface 24 is S and the cross-sectional area at the effective diameter of the second region is A,

Equation

[0030] The contact surface 24 may be, for example, a surface with unevenness. Such unevenness is fine unevenness or the like that suppresses the sliding between the friction surfaces with respect to the object to be held and functions to adhere to the object to be held. The uneven contact surface 24 can be formed by shot peening, arranging an anti-slip material, etc. Instead of providing fine unevenness, treatments such as applying an anti-slip paint or spraying an anti-slip spray may be performed.

[0031] Also, the uneven shape of the contact surface 24 may be a mountain shape, a wave shape, etc., and may extend continuously or intermittently in a predetermined direction. Also, it may be fine unevenness formed in the circumferential direction and the radial direction such as a so-called knurl. Of course, the shape and size of the unevenness are not particularly limited, and can be set to an appropriate shape and size as long as it can adhere to the object to be held. Note that the height of the uneven shape of the contact surface 24 can be set so that the contact surface with the object to be held can be deformed and indented. In particular, if this deformation is set within the range where it remains in the elastic deformation region, the object to be held can be firmly clamped without being damaged. Of course, it is also possible to set it so that it reaches the plastic deformation region.

[0032] The insertion hole 26 has a concave portion 28 whose diameter is enlarged so that the head of the bolt 19 fits on the contact surface 24 side. The bottom of the concave portion 28 is set to a spherical shape that is substantially concentric with the spherical surface portion 20. Further, the insertion hole 26 has an inverted taper shape in which its inner diameter is larger than the outer diameter of the bolt 19 and gradually increases in diameter from the concave portion 28 side toward the convex surface portion 22 side.

[0033] Therefore, the support member 20 is installed in the recess 8 so that the insertion hole 26 communicates with the female screw hole 8a, and as a result, it is disposed opposite to the pressing portion 14. Then, the bolt 19 is inserted into the insertion hole 26 and screwed into the female screw hole 8a, and the support member 20 is fixed to the receiving portion 3. Since there is a gap 50 between the insertion hole 26 and the bolt 19 as shown in FIG. 5(a), the support member 20 arranged in the recess 8 can tilt by the amount of the gap 50 as shown in FIG. 5(b). If the gap 50 is configured in a substantially conical shape (frustum shape), the tilting angle of the support member 20 can be increased, which is effective. Here, since the spherical convex surface portion 22 of the support portion 29 fits into the recess 8, it tilts in substantially all directions in a plan view. That is, in the state shown in FIG. 5, it can tilt in the left-right direction, forward, and backward.

[0034] Next, the axial displacement of the shaft portion 12 (pressing body 10) accompanying the rotational operation of the operation portion 16 will be described. As described above, the shaft portion 12 is screwed into the operation portion 16 and locked in the circumferential direction with respect to the hole portion 6, that is, the relative rotation with respect to the shaft support portion 2 is restricted. Further, the axial displacement of the operation portion 16 with respect to the shaft support portion 2 is restricted by the position regulating cover 18. Therefore, when torque is applied to the operating portion 16, the shaft portion 12 is displaced in the axial direction while remaining non-rotating with respect to the shaft support portion 2. That is, when the operating portion 16 is rotated, the rotation of the shaft portion 12 is restricted by the shaft support portion 2, so as a result, the operating portion 16 rotates relative to the shaft portion 12. Also, the operating portion 16 and the shaft portion 12 that are screwed together can be screwed axially by the relative rotation of the operating portion 16 with respect to the shaft portion 12. However, since the axial displacement of the operating portion 16 is restricted, only the shaft portion 12 is displaced in the axial direction while remaining non-rotating with respect to the shaft support portion.

[0035] Thereby, when the operating portion 16 is rotated clockwise (rotated in the clockwise direction), the shaft portion 12 is displaced in a direction approaching the receiving portion 3. On the other hand, when the operating portion 16 is rotated counterclockwise (rotated in the counterclockwise direction), the shaft portion 12 is displaced in a direction retreating from the receiving portion 3.

[0036] When the clamping and holding member 1 clamps the object to be held between the pressing portion 14 and the support member 20, first, as shown in FIG. 6(a), the operating portion 16 is rotated counterclockwise to retract the shaft portion 12 with respect to the support member 20, and a space is provided between the pressing portion 14 and the support member 20 to an extent that the object to be held can be arranged.

[0037] Next, the object to be held is arranged in the space between the pressing portion 14 and the support member 20. Here, two objects to be held are arranged in a stacked state. Therefore, after arranging the object to be held in the space between the pressing portion 14 and the support member 20 as shown in FIG. 6(b), the operating portion 16 is rotated clockwise to advance the shaft portion 12 toward the support member 20 as shown in FIG. 6(c). By further rotating the operating portion 16 clockwise, the pressing portion 14 comes into contact with and presses the object to be held. That is, the pressing body 10 presses the object to be held by the advancement of the shaft portion 12.

[0038] When the object to be held is clamped by the pressing body 10 and the support member 20, the support member 20 can suppress the displacement of the object to be held in the direction orthogonal to the axis. For example, when the object to be held is subjected to a rightward external force as shown by the arrow A in FIG. 7, the support member 20 that supports the object to be held tilts to support the object to be held more firmly. That is, the unevenness of the friction surface and / or the contact surface 24 between the object to be held and the support member 20 engages (wedges) with the object to be held, so that a rightward external force along the arrow A acts on the support member 20, and a couple force acts to tilt the support member 20 to a posture in which the right end as shown in FIG. 5(b) protrudes. Therefore, a part of the support member 20 presses the object to be held toward the pressing body 10 so as to protrude toward the object to be held side.

[0039] As described above, according to the clamping and holding member 1 of the present embodiment, the operating portion 16 is rotated to displace the shaft portion 12 along the axial direction, and the shaft portion 12 is displaced in the axial direction while remaining non-rotating. Therefore, the pressing portion 14 presses without sliding on the surface of the object to be held. Thus, the object to be held can be clamped without being damaged between the pressing portion 14 and the support member 20.

[0040] Further, since the shaft portion 12 does not rattle in the axial direction within the hole portion 6, the shaft portion 12 and the operating portion 16 cannot rotate relative to each other due to vibrations transmitted from the object to be held or external forces in the direction orthogonal to the axis. Therefore, the pressing body 10 does not displace in the axial direction, and the object to be held can be clamped and held extremely firmly in the same manner as the tensile friction joint in which the object to be held is clamped and joined by a conventional bolt and nut, and a compression friction joint can be realized. Therefore, the clamping and holding member 1 can perform friction joining in a state where the tip portion (pressing portion 14) of the pressing body 10 is pressed against the object to be held and the object to be held is clamped extremely firmly. Further, since the pressing body 10 is prevented from rattling in the direction orthogonal to the axis with respect to the shaft support portion 2, the friction joining state can be maintained even if an external force in the direction orthogonal to the axis or the like acts on the pressing body 10 via the object to be held.

[0041] Further, since the support member 20 is installed to be tiltable, when an external force is applied in a direction in which the object to be held can escape from the state of being pinched between the pressing body 10 and the support member 20, the support member 20 tilts and presses the object to be held toward the pressing body 10 to pinch the object to be held more firmly. Therefore, it is possible to prevent the object to be held from being removed. When pinching a tapered object to be held, the support member 20 can tilt along the taper and pinch it in a close contact state.

[0042] In the above-described embodiment, the cross-sectional shape of the first region 12a of the shaft portion 12 and the shape of the hole portion 6 are substantially hexagonal, and the rotation of the shaft portion 12 is locked within the hole portion 6 so that the pressing body 10 does not rotate relative to the shaft support portion 2. However, the structure in which the pressing body 10 does not rotate relative to the shaft support portion 2 is not limited to this. For example, an intervening member may be disposed between the shaft portion 12 and the hole portion 6 so that the pressing body 10 does not rotate relative to the shaft support portion 2.

[0043] FIG. 8 is a diagram showing another configuration example of the pressing body. The pressing body 30 can be configured by a shaft portion 32, an intervening member 34, a pressing portion 14, an operation portion 16, a position regulating cover 18, and the like. In this case, the hole portion 6 has a fitting hole 40 in which the intervening member 34 can be disposed at its open end.

[0044] The shaft portion 32 has a first region 32a having a circular cross-section that can be inserted into the hole portion 6 from one end side to the middle portion, and a second region 32b to which the operation portion 16 can be attached from the other end side to the middle portion. The first region 32a is set to have a larger diameter than the second region 32b. The shape of the hole portion 6 is a circular shape or the like through which the shaft portion 32 can be inserted, and is set to a circular shape having a size substantially corresponding to the outer shape and outer diameter of the first region 32a. Therefore, the first region 32a can be inserted into the hole portion 6 so as to be able to advance and retreat without play.

[0045] On the second region 32b, a male thread portion with a left-handed thread is formed on the outer peripheral surface. The second region 32b has a notch surface 38 in which the male thread portion is notched along the axial direction. The second region 32b is set such that the maximum outer diameter is smaller than the outer diameter of the first region 32a.

[0046] The intervening member 34 forms an annular shape, with an inner peripheral surface configured to be insertable with the second region 32b and an outer peripheral surface configured to be insertable into the fitting hole 40. Further, the intervening member 34 has an engaging surface 36 whose length from the center sequentially decreases on its outer shape. The fitting hole 40 has a hole shape for inserting the intervening member 34. That is, the fitting hole 40 has a hole shape corresponding to the outer shape of the intervening member 34, and a part of the inner peripheral surface engages with the engaging surface 36 in the circumferential direction.

[0047] The assembly of the pressing body 30 is performed by inserting the shaft portion 32, through which the second region 32b has been inserted into the intervening member 34, into the hole portion 6. At this time, the shaft portion 32 is inserted into the hole portion 6 until the intervening member 34 reaches the position where it is to be inserted into the fitting hole 40. Then, the operating portion 16 is screwed onto the male screw portion of the second region 32b, and the position regulating cover 18 is fixed to the shaft support portion 2.

[0048] Even with such a pressing body 30, the pressing body 30 can be displaced in the axial direction while remaining non-rotatable with respect to the object to be held. Therefore, the pressing portion 14 presses without sliding on the surface of the object to be held. Thus, the object to be held can be clamped without being damaged between the pressing portion 14 and the support member 20. Also, since the shaft portion 32 does not play in the axial direction within the hole portion 6, the pressing body 30 does not displace in the axial direction, and a friction joining state in which the object to be held is clamped and held extremely firmly can be maintained.

[0049] Also, although the support member 20 is disposed opposite to the pressing body 10, the positions of the support member 20 and the pressing body 10 can be set as appropriate. That is, the axis of the bolt 19 inserted through the support member 20 may be located on the extension line of the axis of the hole portion 6, or may be biased toward the anti-holder 4 side with respect to the axis of the hole portion 6. That is, the axis c2 of the bolt 19 shown by the dashed-dotted line in FIG. 9 is biased toward the anti-holder 4 side with respect to the axis c1 of the hole portion 6 shown by the dashed line. The support member 20 may be displaced in the direction perpendicular to the axis from the front of the pressing body 10 and arranged. In the state shown in Fig. 9, when a force in the direction of the anti-holder 4 indicated by the arrow A acts on the object to be held, the support member 20 tilts such that the end on the holder 4 side presses the object to be held toward the pressing body 10 side. That is, the pressing position by the support member 20 is in the vicinity of the position facing the axis of the pressing body 10, and the holding by clamping the object to be held can be performed more stably.

[0050] Further, the convex surface portion 22 of the support member 20 is spherical, but of course, it is not limited thereto, and it may be a cylindrical convex surface portion 22 as shown in Fig. 10. When it is cylindrical, the directions of tilting in two opposite directions are determined. When the convex surface portion 22 is cylindrical, the bottom surface shape of the concave portion 8 is preferably a concave cylindrical surface so that the convex surface portion 22 can be slidably fitted. Also, the shape of the contact surface 24 of the support member 20 in plan view can be appropriately set, and in addition to the circular shape as shown in Fig. 1 and the rectangular shape as shown in Fig. 10, it may be a non-rectangular polygon such as a triangular shape or a pentagonal shape, an elliptical shape, an oval shape, etc.

[0051] Also, although the above-described pressing body has been described as being able to advance and retreat while the shaft portion is non-rotatable with respect to the shaft support portion, as long as at least the pressing portion does not slide on the object to be held, the shaft portion may be configured to rotate. For example, the pressing body may be configured such that the pressing portion is formed separately from the shaft portion and the pressing portion is loosely fitted to the shaft portion so that the shaft portion can rotate relative to the pressing portion.

[0052] Fig. 11 is a cross-sectional view showing a clamping and holding member. The pressing body 60 can be composed of a shaft portion 62 and a pressing portion 64. The shaft portion 62 is a male screw-like member having spiral stripes formed on substantially the entire outer peripheral surface. The pressing portion 64 is formed so as to be attachable to the tip of the shaft portion 62 and has a concavo-convex surface facing the support member 20, that is, a concavo-convex surface that contacts the object to be held. Further, the shaft support portion 2 has a female screw spiral groove that engages with the spiral stripes of the shaft portion 62 on the inner peripheral surface forming the hole portion 6.

[0053] Here, FIG. 12 is a diagram showing an example of the connection between the shaft portion 62 and the pressing portion 64. As shown in FIG. 12(a), the pressing portion 64 has a cross-sectional concave shape that can cover the tip of the shaft portion 62 and surround the outer peripheral surface, and a convex portion 62a that protrudes radially inward is provided on the inner peripheral surface. On the other hand, a circumferential groove 64a is formed on the outer peripheral surface of the tip side of the shaft portion 62. Here, the convex portion 62a interferes with the outer peripheral surface of the shaft portion 62, and its protruding length is set so as to be loosely fitted into the circumferential groove 64a.

[0054] The mounting of the pressing portion 64 to the shaft portion 62 is performed by arranging the pressing portion 64 on the tip side of the shaft portion 62 and pressing the pressing portion 64 in the axial direction so that the convex portion 62a fits into the circumferential groove 64a. As a result, the pressing portion 64 is rotatably supported with respect to the shaft portion 60.

[0055] Of course, the connection between the shaft portion 62 and the pressing portion 64 is not limited to the above, and can be performed by an appropriate method. For example, as shown in FIG. 12(b), a spherical tip portion 62b may be provided on the shaft portion 60, and the pressing portion 64 may surround the tip portion 62b and be locked in the axial direction. That is, the pressing portion 64 may have a concave portion 64b with a narrowed opening, and the tip portion 62b may be fitted into the concave portion 64b while the tip portion 62b and / or the concave portion 64b is elastically deformed. Even in this case, the pressing portion 64 can be connected to the shaft portion 62 so as to be relatively rotatable. The pressing portion 64 may be set with a cross-sectional area or the like so that the shear strength is stronger than that of the shaft portion 62. For example, the cross-sectional area S of the pressing portion 64 with respect to the cross-sectional area A at the effective diameter of the thread of the shaft portion 62 is

Equation

[0056] According to the above configuration, since the uneven surface of the pressing portion 64 abuts against the object to be held, the friction between the pressing portion 64 and the object to be held can be set larger than the friction between the pressing portion 64 and the shaft portion 62. Therefore, when the pressing portion 64 is in contact with the object to be held, it is possible to prevent the pressing portion 64 from idling with respect to the shaft portion 62 and coming into sliding contact with the object to be held.

[0057] FIG. 13 is a diagram showing an example of the shaft portion 70. The shaft portion 70 may have different male screw structures on one end side and the other end side. That is, the shaft portion 70 is formed by a right-handed helical thread on one end side (the region corresponding to the first region described above), and a supported screw portion 72 that is screwed into a female screw helical groove provided on the inner peripheral surface of the shaft support portion 2 is arranged. Further, the shaft portion 70 arranges both screw portions 74 of male screw helical grooves of both right-handed and left-handed screws in which a right-handed helical groove and a left-handed helical groove are formed to overlap in the same region on the other end side (the region corresponding to the second region described above).

[0058] Both screw portions 74 are formed by overlapping two types of male screw helical grooves, a first male screw helical groove that is a right-handed screw and a second male screw helical groove that is a left-handed screw, in the same region. On both screw portions 74, substantially crescent-shaped threads 76 that are continuous in the plane direction perpendicular to the axis (screw axis) are alternately provided on one side (the right side in FIG. 13) and the other side (the left side in FIG. 13) of the shaft portion 70. By configuring the threads 76 in this way, two types of helical grooves, a helical groove that turns clockwise and a helical groove that turns counterclockwise, can be formed between the threads 76. Therefore, both screw portions 74 can be screwed with any female screw body of a right-handed screw and a left-handed screw.

[0059] When the pressing body 10 is configured using the shaft portion 70, as shown in FIG. 14, in the shaft portion 70, the supported screw portion 72 is screwed into and supported by the shaft support portion 2 within the hole portion 6, and the operation portion 16 is screwed into the second male screw helical groove of both screw portions 74. Note that the first male screw helical groove of both screw portions 74 can be screwed with the hole portion 6. Further, the axial position of the operation portion 16 with respect to the shaft support portion 2 is regulated by the position regulating cover 18.

[0060] The pressing body 10 rotates the operation part 16 relative to the shaft part 70, and rotates the shaft part 70 in the opposite direction by the reaction of the torque applied to the operation part 16. That is, as shown in Fig. 15(a), when the operation part 16 is rotated clockwise, the shaft part 70 rotates counterclockwise with respect to the shaft support part 2 and is displaced in a direction of retreating from the support member 20 due to the reaction of the torque applied to the operation part 16. Also, as shown in Fig. 15(b), when the operation part 16 is rotated counterclockwise, the shaft part 70 rotates clockwise with respect to the shaft support part 2 and is displaced toward the support member 20 due to the reaction of the torque applied to the operation part 16.

[0061] In this way, by screwing the operation part 16 onto both screw parts 74 of the shaft part 70, when torque is applied to the operation part 16, a torque in the opposite direction acts on the shaft part 70, causing the shaft part 70 to rotate and be displaced in the axial direction. Thereby, the object to be held can be pressed, and the object to be held can be clamped and held.

[0062] Also, although the pressing part 64 is configured separately from the shaft part, since the cross-sectional area of the pressing part 64 is set so that its shear strength is stronger than that of the shaft part, it is possible to prevent the pressing part 64 from being sheared and broken prior to the shaft part even when it is in direct contact with the object to be held. Also, it is possible to prevent the pressing by the pressing body 10 from being released due to vibrations from the object to be held and forces in the direction orthogonal to the shaft. This is because the shaft part 70 cannot rotate relative to the hole part 6 and the operation part 16 simultaneously.

[0063] Specifically, the shaft part 70 has a supported screw part 72 screwed into the hole part 6 and both screw parts 74 screwed into the operation part 16, and the axial displacement directions due to relative rotation are different. When only the shaft part 70 is rotated clockwise, the region (supported screw part 72) screwed into the hole part 6 is displaced axially toward the support member 20 side. In contrast, the region (both screw parts 74) of the shaft part 70 screwed into the operation part 16 is displaced axially so as to retreat from the support member 20.

[0064] Therefore, since the shaft portion 70 tends to be displaced in opposite directions in the two regions (the screw portion 72 to be supported and the double screw portions 74), as a result, the shaft portion 70 cannot rotate relative to the hole portion 6 and the operation portion 16 at the same time. Thus, the pressing body 10 can be frictionally joined in a state where it is not displaced in the axial direction and firmly holds the object to be held. Further, the pressing body 10 can maintain the state of frictional joining even when receiving vibration or an external force in a direction orthogonal to the axis through the object to be held.

Explanation of Signs

[0065] 1... fastening and holding member, 2... shaft support portion, 3... receiving portion, 4... holding body, 10, 30, 60... pressing body, 12, 32, 62, 70... shaft portion, 14, 64... pressing portion, 16... operation portion, 18... position regulating cover, 20... support member, 22... convex portion, 24... contact surface, 26... insertion hole, 34... intervening member, 40... fitting hole, 62a... convex portion, 64a... circumferential groove, 72... screw portion to be supported, 74... double screw portions.

Claims

**Claim 1**: A pressing body, a shaft support portion that axially supports the pressing body so as to be insertable and retractable, a holding body that holds a receiving portion disposed opposite to the shaft support portion in a fixed position, a pressing portion provided on the pressing body that can press a holding target facing the receiving portion, and an operation portion that is mounted so as to surround a shaft portion provided on the pressing body and enables the pressing body to be advanced and retracted without rotation. The shaft portion has a columnar shape and is axially supported by the shaft support portion so that rotation around the axis is restricted. By the rotational operation of the operation portion, it is displaceable in the axial direction while remaining non-rotating. The pressing portion is a clamping and holding member characterized in that it can press the holding target when the shaft portion advances. **Claim 2** The shaft portion has a first region axially supported by the shaft support portion and a second region on which the operation portion is mounted. The pressing portion is located at the tip of the first region. The first region has a columnar shape that can engage with the shaft support portion in the circumferential direction. The second region has a male screw spiral groove. The shaft support portion has a hole that engages with the inserted first region in the circumferential direction, characterized in that it is the clamping and holding member according to Claim 1. **Claim 3** The first region of the shaft portion has a cross-sectional shape that is polygonal, oval, or elliptical. The hole has a shape corresponding to the cross-sectional shape, characterized in that it is the clamping and holding member according to Claim 2. **Claim 4** The first region has a shape with a notch in a part of its circumferential surface. The hole is characterized in that its inner circumferential surface engages with the notched portion of the first region in the circumferential direction, and it is the clamping and holding member according to Claim 2. **Claim 5** The shaft portion has a first region with a circular cross-section axially supported by the shaft support portion and a second region on which the operation portion is mounted. The pressing portion is located at the tip of the first region. The second region has a male screw spiral groove formed on its outer circumferential surface and a notch surface formed by notching the male screw spiral groove along the axial direction. The hole has an insertion fitting portion arranged at the opening and having a diameter larger than that of the first region. The insertion fitting portion has an engagement surface whose length from the axis gradually decreases on its inner circumferential surface. It includes an intervening member inserted into the opening and surrounding the second region. The intervening member is characterized in that its outer circumferential surface is circumferentially locked to the opening and its inner circumferential surface is circumferentially locked to the engagement surface, and it is the clamping and holding member according to Claim 2. **Claim 6** The pressing portion has a concavo-convex surface that contacts the holding target, characterized in that it is the clamping and holding member according to any one of Claims 1 to 5. **Claim 7** The receiving part has a support member that makes surface contact with the object to be held and is tiltable with respect to the object to be held, and is the clamping and holding member according to any one of claims 1 to 6.

8. The receiving part has a recess with a spherical or curved bottom surface, The support member has a convex portion on a protruding surface along the shape of the bottom surface, The clamping and holding member according to claim 7, wherein the support member is disposed on the receiving part such that the convex portion can be in sliding contact with the recess.

9. The clamping and holding member according to claim 7 or 8, wherein the support member has an uneven contact surface that contacts the object to be held.

10. The clamping and holding member according to any one of claims 7 to 9, wherein the center of the support member and the center of the pressing part are offset in a direction along the axis of the shaft part.

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