JP2007069336A - Squeezing jig - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a squeezing jig which can restore an once-expanded annular member to the original diameter when the annular member is fitted in a fitting groove formed on the outer peripheral surface of a cylindrical member. <P>SOLUTION: The squeezing jig comprises a contracting portion 1, a squeezing band 2 extending from the contracting portion 1 to the contracting portion 1 so as to form a loop shape winding portion 2a, and a pulling portion 3, such as a winding device 30, for pulling the end portion of the squeezing band 2 extending toward the opposite side of the loop shape winding portion 2a passing through the contracting portion 1. The diameter of the loop shape winding portion 2a is reduced by pulling the end portion of the squeezing band 2 by winding the squeezing band 2 by means of the winding device 30. Thus, the annular member, such as a seal ring 51, can be squeezed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a tightening jig used for tightening and correcting an annular body after mounting the annular body in a mounting groove formed on an outer peripheral surface of a cylindrical body such as a piston.

Conventionally, for example, a mounting jig described in Patent Document 1 is known as a jig for mounting a piston seal in a mounting groove formed continuously in the circumferential direction on the outer peripheral surface of a piston. .
JP 2001-162553 A

  That is, the mounting jig described in Patent Document 1 is composed of a guide jig and a push-in jig, and a piston seal is extrapolated to the guide jig placed on the piston and pushed in the axial direction by the push-in jig. The piston seal expands while moving along the outer peripheral surface of the conical surface of the guide jig, and when it reaches the outer periphery of the mounting groove of the piston, the mounting is performed by its own diameter reducing force. It is designed to be fitted in the groove.

  Here, FIG. 7 is a partial cross-sectional view showing the mounting state of the combination type piston seal, in which reference numeral 100 is a cylinder, 200 is a piston arranged on the inner periphery of the cylinder 100 so as to be axially movable, In the mounting groove 200b formed continuously in the circumferential direction on the outer peripheral surface 200a of the piston 200, a seal ring 301 made of a synthetic resin having a low friction coefficient, and a close force of the seal ring 301 to the inner peripheral surface 100a of the cylinder 100 A piston seal 300 is attached in which a back ring 302 made of a rubber-like elastic material such as NBR is combined in the radial direction.

  When the combination type piston seal 300 as shown in FIG. 7 is mounted in the mounting groove 200b of the piston 200, for example, using a mounting jig as in Patent Document 1, the buckling 302 is first mounted, and then the seal is sealed. The ring 301 is attached. However, since the seal ring 301 is made of a synthetic resin, unlike the back ring 302 made of a rubber-like elastic material, once the diameter is expanded by a mounting jig or the like, the original diameter can be restored to its original diameter only by its own restoring force. Is not restored. Therefore, it is necessary to correct the seal ring 301 to the original diameter using a tightening jig.

  FIG. 8 is an explanatory view showing the restoration work of the seal ring by the conventional tightening jig. That is, the tightening jig 400 shown in FIG. 8 has a cylindrical shape and a conical diaphragm surface 401 is formed on the inner periphery of the tip, and the back ring 302 and the seal ring 301 are mounted in the mounting groove 200b. From this, the tightening jig 400 is extrapolated to the piston 200 so that the seal ring 301 is squeezed from the outer periphery by the throttle surface 401 to be reduced in diameter. However, the tightening jig 400 having such a configuration needs to be prepared in a size corresponding to each of the diameter dimensions of the piston 200.

  The present invention has been made in view of the above points, and a technical problem thereof is to mount an annular body in a mounting groove formed on an outer peripheral surface of a cylindrical body such as a piston. At this time, the object is to provide a tightening jig for restoring the annular body once expanded in diameter to the original diameter.

  The technical problem described above can be effectively solved by the present invention. That is, the tightening jig according to the invention of claim 1 includes a throttle portion, a tightening band extending from the throttle portion so as to form a looped winding portion and returning to the throttle portion again, and the loop shape passing through the throttle portion. A tension portion that pulls an end portion of the fastening band extending to the opposite side to the winding portion.

  That is, in this tightening jig, the end of the tightening band passed through the throttle portion is pulled by the pulling portion, so that the looped winding portion of the tightening band is reduced in diameter. For this reason, by extrapolating the looped winding part to the annular body expanded in the process of fitting into the mounting groove of the cylindrical body, the diameter of the looped winding part is reduced as described above. The annular body can be tightened.

  According to a second aspect of the present invention, there is provided a tightening jig comprising a winding device in which the tension portion according to the first aspect winds the tightening band around the rotating shaft.

  According to the configuration of the second aspect, as the tightening band is wound around the rotating shaft, the tightening band is pulled through the throttle portion, and the loop-shaped wound portion is reduced in diameter.

  According to a third aspect of the present invention, there is provided a tightening jig according to the second aspect, wherein the throttle portion is formed in a case that supports the rotating shaft of the winding device.

  According to the configuration of the third aspect, since the winding device is supported by the case and the throttle portion is formed in the case, in winding the tightening band (reducing the diameter of the looped winding portion), It is wound around the rotating shaft of the winding device in the case through the throttle portion.

  According to the tightening jig according to the first to third aspects of the present invention, the loop-shaped winding portion of the tightening band is extrapolated to the annular body whose diameter has been expanded in the process of fitting into the mounting groove of the cylindrical body, By pulling the end of the tightening band that has passed through the portion with the tension portion, the looped winding portion is reduced in diameter and the annular body is tightened, so that the operation of reducing the diameter of the annular body can be easily performed, Since the size of the loop-shaped wrapping portion freely changes depending on the amount of tension of the tightening band from the restricting portion, it can be used regardless of the outer diameter of the annular body to be tightened or the cylindrical body to be attached.

  Hereinafter, preferred embodiments of a fastening jig according to the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view schematically showing a first form of a fastening jig according to the present invention. As shown in FIG. 1, the tightening jig includes a narrowing portion 1, a tightening band 2 extending from the narrowing portion 1 so as to return to the narrowing portion 1 again by forming a loop-shaped winding portion 2 a, A tension portion 3 is provided for pulling the end portions 2b, 2b of the fastening band 2 that extends to the opposite side of the loop-shaped winding portion 2a through the throttle portion 1.

  Therefore, according to the tightening jig having the configuration shown in FIG. 1, in the state where the throttle portion 1 is fixed, the end 2b of the tightening band 2 is pulled by the tension portion 3, or the tension portion 3 is fixed. By moving the portion 1 toward the loop-shaped wrapping portion 2a side of the tightening band 2, in other words, by pulling the end portion 2b of the tightening band 2 through the throttle portion 1 with the tension portion 3, the loop shape The diameter of the winding part 2a is reduced.

  Therefore, after the loop-shaped winding portion 2a is extrapolated to an annular body (not shown) to be tightened, the loop-shaped winding portion 2a can be tightened by reducing the diameter of the loop-shaped winding portion 2a as described above. Further, since the size of the loop-shaped winding portion 2a changes steplessly depending on the amount of tension of the tightening band 2 from the narrowed portion 1, it is possible to cope with various diameters of the annular body.

  2 is a cross-sectional view showing a more specific configuration of the fastening jig according to the present invention, and FIG. 3 is a cross-sectional view taken along line III-III in FIG. That is, in the tightening jig according to this embodiment, a slit 11 corresponding to the narrowed portion 1 in FIG. 1 is formed in the case 10, and the winding device 30 corresponding to the pulling portion 3 in FIG. Is provided.

  Specifically, it has a cylindrical surface-shaped concave surface portion 12 that is gently curved, and a slit 11 as a diaphragm portion is elongated at a central portion of the concave surface portion 12 in a direction substantially parallel to the axis of the cylindrical surface. Has been established.

  The winding device 30 as the pulling portion 3 extends in a direction substantially parallel to the axial center of the cylindrical surface of the concave portion 12 in the case 10 and is rotatable on the side walls 13 and 14 of the case 10 via bearings (not shown). The rotary shaft 31 is pivotally supported, and a handle 32 is provided at one end of the rotary shaft 31. In addition, the winding device 30 is preferably provided with a lock mechanism that can restrain the rotation of the rotary shaft 31 and the handle 32.

  The fastening band 2 is made of a band-shaped material, and is led out from the inside of the case 10 to the outside of the concave surface portion 12 of the case 10 through the slit 11 to form a looped winding portion 2a. , It passes through the slit 11 again and extends so as to return to the inside of the case 10. That is, the tightening band 2 passes through the slit 11 so as to overlap each other, and the end 2b extending into the case 10 on the side opposite to the loop-shaped winding portion 2a overlaps with the rotating shaft 31 of the winding device 30. It is fixed and wound around the outer periphery of the rotating shaft 31 rotated by the handle 32. Further, the width w of the slit 11 is slightly larger than 2t, where t is the thickness of the fastening band 2. The tightening band 2 is flexible so that it can be wound around the rotary shaft 31, and it is difficult to damage a seal ring, which will be described later, and has the required tensile strength and durability. The material is not limited.

  Next, the process of mounting the piston seal on the piston using the fastening jig having the above-described configuration will be described with reference to FIGS. 4 is a cross-sectional view of the usage state cut at the same position as FIG. 2, and FIG. 5 is a cross-sectional view taken along line VV in FIG.

  4 and 5, reference numeral 4 is a piston, and a mounting groove 4 a continuous in the circumferential direction is formed on the outer peripheral surface thereof. The mounting groove 4a is formed with a seal ring 51 made of a synthetic resin having a low friction coefficient such as PTFE and a seal ring 51 made of a rubber-like elastic material such as NBR by using a jig as described in Patent Document 1, for example. A piston seal 5 is attached in combination with a buckling 52 located on the inner periphery.

  Here, since the seal ring 51 is made of a synthetic resin, once the diameter of the seal ring 51 is larger than the outer diameter of the piston 4 in the mounting process in the mounting groove 4a, the original diameter can be restored to the original diameter only by its own restoring force. Is not restored. The tightening jig according to the illustrated form is used to correct such a seal ring 51 to the original diameter.

  In this straightening operation, the loop diameter or circumferential length of the loop-shaped winding portion 2a is set to the seal ring 51 by fully pulling out the fastening band 2 from the slit 11 of the case 10 to the outside, as shown by a one-dot chain line in FIG. This loop-shaped winding portion 2 a is extrapolated to a seal ring 51 mounted in the mounting groove 4 a of the piston 4.

  Next, when the rotating shaft 31 is rotated by manually rotating the handle 32 of the winding device 30, the end 2 b of the tightening band 2 is wound around the outer periphery of the rotating shaft 31. Is pulled into the case 10 through the slit 11, the diameter of the looped winding portion 2 a is reduced, and the seal ring 51 is tightened from the outer periphery. Therefore, by tightening the seal ring 51 to such an extent that the back ring 52 made of a rubber-like elastic material on its inner periphery is appropriately compressed, the seal ring 51 is plastically deformed in the direction of diameter reduction and corrected (restored) to a preferred diameter. ).

  If the winding device 30 is provided with a lock mechanism capable of restraining the rotation of the rotary shaft 31 and the handle 32, the diameter of the loop-shaped winding portion 2a can be set to a desired value with an appropriate tightening force applied to the seal ring 51. Can be time-constrained.

  In addition, the size of the loop-shaped winding portion 2a is freely changed according to the winding amount of the tightening band 2 by the winding device 30, so that the radius of the seal ring 51 to be tightened is within the radius of curvature of the concave portion 12 of the case 10. If it is, it can respond to the seal ring 51 of various radii.

  In the above-described embodiment, the tension portion 3 (winding device 30) is configured to pull both end portions 2b and 2b of the fastening band 2, but only one end portion 2b is pulled. Also good. FIG. 6 is an explanatory view schematically showing a second embodiment of the fastening jig according to the present invention as such an example.

  That is, in this embodiment, as shown in FIG. 6, the narrowed portion 1 and the one end portion 2 c fixed to the narrowed portion 1 form a single looped winding portion 2 a so as to pass through the narrowed portion 1. A fastening band 2 that extends, and a tension part 3 that pulls the other end 2d of the fastening band 2 that protrudes through the throttle part 1 to the opposite side of the loop-shaped winding part 2a are provided.

  Therefore, also in the configuration of FIG. 6, the end portion 2 d of the tightening band 2 is pulled by the tension portion 3 in a state where the throttle portion 1 is fixed, or the throttle portion 1 is fixed to the tightening band 2 while the tension portion 3 is fixed. By moving the loop-shaped winding part 2a toward the loop-shaped winding part 2a, in other words, by pulling the end part 2b of the tightening band 2 that has passed through the throttle part 1 with the tension part 3, the loop-shaped winding part 2a is reduced in diameter. . However, in this case, for example, if the pulling speed by the pulling portion 3 is constant, the diameter reduction speed becomes slower than that in FIG.

  The configuration according to this embodiment is also applied to, for example, FIGS. 2 and 3 to fix the one end 2c of the fastening band 2 to the slit 11 in the case 10 or the vicinity thereof, and to wind the other end 2d as a tension portion. It can be made to wind around 30 rotating shafts 31.

  In addition, as the tension | pulling part 3, various things, such as what advances / retreats with a screw shaft with respect to the aperture | diaphragm | squeeze part 1, other than the winding device 30 as mentioned above, can be considered.

It is explanatory drawing which shows schematically the 1st form of the fastening jig | tool which concerns on this invention. It is sectional drawing which shows the specific structure of the fastening jig | tool which concerns on this invention. It is the III-III sectional view in FIG. It is sectional drawing of the use condition cut | disconnected in the same position as FIG. It is VV sectional drawing in FIG. It is explanatory drawing which shows schematically the 2nd form of the clamping jig which concerns on this invention. It is a fragmentary sectional view which shows the mounting state of the combination type piston seal. It is explanatory drawing which shows the restoration operation | work of the seal ring by the conventional jig | tool.

Explanation of symbols

1 Diaphragm 10 Case 11 Slit (diaphragm)
12 Concave parts 13 and 14 Side wall 2 Tightening band 2a Loop winding part 2b-2d End part 3 Tension part 30 Winding device (tensile part)
31 Rotating shaft 32 Handle 4 Piston 4a Mounting groove 5 Piston seal 51 Seal ring 52 Back ring

Claims (3)

  The throttle part (1, 11), the tightening band (2) extending from the throttle part (1, 11) to the loop part (2a) and returning to the throttle part (1, 11); A tension portion (3) for pulling the end portions (2b, 2d) of the tightening band (2) extending to the opposite side of the loop-shaped winding portion (2a) through the throttle portions (1, 11). Tightening jig.   2. The tightening treatment according to claim 1, characterized in that the tension part (3) comprises a winding device (30) for winding the end part (2b, 2d) of the tightening band (2) around the rotating shaft (31). Ingredients.   The tightening jig according to claim 2, wherein the throttle part (11) is formed in a case (10) that supports the winding device (30).

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