JP5019039B2 - Seal ring mounting jig - Google Patents

Description

The present invention relates to a jig used for mounting a synthetic resin seal ring divided in one circumferential direction on an annular groove formed on a cylindrical outer peripheral surface.

  In recent years, synthetic resin seal rings have been frequently used in the operating parts of hydraulic equipment. FIG. 3 is a partial cross-sectional view showing a mounting state of this type of seal ring, FIG. 4 is a view of this type of seal ring viewed from a direction parallel to the axis, and FIG. 5 is a conventional seal ring mounting jig. FIG.

  In FIG. 3, reference numeral 1 denotes a housing of the device, 2 denotes a shaft inserted through the housing 1, and an annular groove 2a is formed on the outer peripheral surface of the shaft 2, and a seal ring 3 is formed in the annular groove 2a. Is installed in a semi-contained state. The seal ring 3 is configured such that the end surface 3a opposite to the space to be sealed is pressed in close contact with the inner surface of the annular groove 2a by the hydraulic pressure P on the space to be sealed, and the outer peripheral surface 3b is The sealing function is achieved in close contact with the surface in a slidable manner.

  The seal ring 3 is made of a synthetic resin and has a structure divided at one place in the circumferential direction as shown in FIG. 4 in order to secure the mounting property to the annular groove 2a. When mounting in the annular groove 2a, as shown by a solid line in FIG. 4, the diameter is once expanded so as to open between the divided end portions 3c and 3d, and then, as shown by a one-dot chain line in FIG. The parts 3c and 3d are fitted into the annular groove 2a so as to abut each other.

  Here, a mounting jig 4 as shown in FIG. 5 is used for mounting the seal ring 3 to the annular groove 2 a formed on the outer peripheral surface of the shaft 2. That is, the jig 4 includes a cylindrical fitting tube portion 4a fitted to the outer periphery of the shaft 2, and a fitting tube portion whose tip can reach the outer peripheral position of the annular groove 2a of the shaft 2 in the fitted state. And an enlarged diameter guide portion 4b formed so that the outer peripheral surface gradually becomes smaller in diameter toward the opposite side of the tip from the fitting cylinder portion, and further introduced from the small diameter end portion of the enlarged diameter guide portion 4b. It consists of part 4c. Then, first, the seal ring 3 supplied to the outer periphery of the introduction portion 4c as shown in 3 (A) is pushed out toward the outer periphery of the fitting tube portion 4a via the enlarged diameter guide portion 4b as shown in 3 (B). As a result, as shown by a solid line in FIG. 4, the diameter is expanded so as to open between the divided end portions 3c and 3d, and further, by pushing, it can be repelled from the tip of the fitting cylinder portion 4a by its own restoring force. Snap fit into the annular groove 2a as shown in 3 (C).

As conventional seal ring mounting jigs, those disclosed in the following patent documents are known.
Utility Model Registration No. 2520472 JP 2005-349547 A

  By the way, since the seal ring 3 tends to be used more severely, a synthetic resin having a high elastic modulus excellent in wear resistance and heat resistance such as PEEK (polyetheretherketone). The application of materials is increasing. However, a synthetic resin material having a high elastic modulus such as PEEK is generally excellent in abrasion resistance, but has a strong restoring force when the seal ring 3 is expanded and deformed for mounting. In the mounting process by the mounting jig 4 shown in FIG. 5, when the snap-fitting is performed from the tip of the fitting tube portion 4a into the annular groove 2a by its own restoring force, the divided end portions 3c and 3d are vigorously brought together. There is a risk of colliding and breaking. In particular, when the divided end portions 3c and 3d have a three-dimensional step shape as shown in FIG. 4, there is a possibility that the corners (corners) of the tips collide with each other to cause chipping.

The present invention has been made in view of the above points, and the technical problem is that the synthetic resin seal ring divided in one circumferential direction is attached to the annular groove. once expanded by sealing rings to provide their own seal ring mounting jig vigorous diameter to split ends each other to prevent damage due to collision by the restoring force.

As means for effectively solving the technical problem described above, the seal ring mounting jig according to the present invention is divided into annular grooves formed on the outer peripheral surface of the seal ring mounting target part at one place in the circumferential direction. In a mounting jig for mounting a synthetic resin seal ring , the fitting can be fitted to the outer periphery of the seal ring mounting target part and the tip can reach the outer circumferential position of the annular groove in the fitted state. The fitting includes a tube portion, and a diameter-enlarged guide portion that extends from the fitting tube portion to the side opposite to the tip thereof and whose outer peripheral surface gradually increases in diameter toward the fitting tube portion side. A tapered surface is formed on the outer peripheral surface of the cylindrical portion so that the diameter gradually decreases toward the tip thereof, and the seal ring can be slid while being reduced in diameter by its own restoring force, and an inclination angle of the tapered surface is 10 to 30 °. It is characterized by being .

  According to the seal ring mounting jig according to the present invention, the seal ring once expanded in the diameter increasing guide portion reduces the diameter of the tapered surface formed on the outer peripheral surface of the fitting tube portion by its own restoring force. However, since it slides toward the tip of the fitting tube portion, the seal ring moves smoothly to the tip of the fitting tube portion. And since this seal ring is snap-fitted into the annular groove after being reduced in diameter to some extent by moving to the tip of the fitting tube portion, the restoring force (reducing force) at the time of snap fitting Therefore, it is possible to effectively prevent the split ends of the seal ring from colliding with force and breaking. Moreover, since the fitting cylinder portion can at least make the outer diameter on the side of the enlarged diameter guide portion a required size, it is possible to ensure the wall thickness necessary for maintaining strength.

  Hereinafter, a preferred embodiment of a seal ring mounting jig according to the present invention will be described with reference to the drawings. FIG. 1 is a half sectional view showing a partial section of this embodiment, and FIG. 2 is a half sectional view showing a use state of the seal ring mounting jig of FIG.

  In FIG. 2, reference numeral 2 is a shaft, and this shaft 2 corresponds to a seal ring mounting target part described in claim 1. An annular groove 2a is formed on the outer peripheral surface of the shaft 2, and the seal ring mounting jig 100 according to the present invention is used for mounting the seal ring 3 in the annular groove 2a.

  The seal ring 3 is the same as that shown in FIG. 4 described above. That is, the seal ring 3 is made of a highly elastic synthetic resin material having excellent wear resistance, such as PEEK, and is divided at one place in the circumferential direction. It has a structured.

  The seal ring mounting jig 100 is made of, for example, metal, can be fitted to the outer periphery of the shaft 2, and in the fitted state, the fitting tube portion 101 in which the tip 101 a can reach the outer peripheral position of the annular groove 2 a of the shaft 2. A diameter-enlarging guide portion 102 that extends from the fitting cylinder portion 101 to the side opposite to the tip 101a and whose outer peripheral surface 102a gradually increases in diameter toward the fitting cylinder portion 101 side, and further this diameter expansion. It consists of a cylindrical introduction part 103 extending from the small-diameter end of the guide part 102. Further, on the outer peripheral surface of the fitting cylindrical portion 101, there are a large-diameter cylindrical surface 101b extending from the large-diameter end portion of the outer peripheral surface 102a of the diameter-enlarging guide portion 102, and a tapered surface 101c that gradually becomes smaller in diameter toward the tip 101a. Is formed.

In addition, since the outer diameter of the large diameter cylindrical surface 101b of the fitting cylinder part 101 is larger than the outer diameter of the axis | shaft 2, naturally the inner diameter of the diameter reduction state of the seal ring 3 shown by FIG. 2 or FIG. The diameter is larger than φ3, and the outer diameter of the introduction portion 103 is smaller than the inner diameter φ3 in the reduced diameter state. The inclination angle θ (see FIG. 1) of the tapered surface 101c with respect to the large-diameter cylindrical surface 101b is 10 to 30 ° . If the angle is less than 10 °, the entire length of the mounting jig becomes long and difficult to handle, and the range of the thin wall by the tapered surface 101c becomes long and the strength decreases. This is because the restoring force cannot be reduced sufficiently.

  In order to mount the annular ring 2a of the shaft 2 using the seal ring mounting jig 100 having the above-described configuration, first, the fitting cylinder portion 101 of the seal ring mounting jig 100 is placed on the outer periphery of the shaft 2 at its end. The seal ring 3 is supplied from the side as shown in FIG. Since the outer diameter of the introduction portion 103 is smaller than the inner diameter φ3 of the reduced diameter state of the seal ring 3, the supply of the seal ring 3 to the introduction portion 103 can be performed smoothly.

  Next, the seal ring 3 on the outer periphery of the introduction portion 103 is pushed out toward the fitting cylinder portion 101 via the outer periphery of the diameter-enlarged guide portion 102 by a finger or an appropriate pressing jig (not shown). Then, since the seal ring 3 moves toward the larger diameter side of the diameter-expanding guide portion 102, the diameter of the seal ring 3 is gradually increased and deformed so as to open between the divided end portions 3c and 3d shown in FIG. As shown in B), it rides on the large-diameter cylindrical surface 101b of the fitting tube portion 101.

  The seal ring 3 riding on the large-diameter cylindrical surface 101b of the fitting cylinder 101 is further pushed to slide the taper surface 101c of the fitting cylinder 101 while reducing its diameter by its restoring force. As shown in FIG. 2C, the front end 101a of the combined tube portion 101 is snap-fitted into an annular groove 2a formed on the outer peripheral surface of the shaft 2.

In the process in which the seal ring 3 is pushed out toward the tip 101 a with the tapered surface 101 c formed on the outer peripheral surface of the fitting cylinder 101, the diameter reducing force derived from its own restoring force is applied to the tip of the fitting cylinder 101. Since it acts as an axial movement force of the seal ring 3 toward 101a, the movement is performed smoothly. Since the outer diameter φa of the tip 101a of the fitting cylinder 101 is smaller than the outer diameter φb of the large cylindrical surface 101b, the seal ring 3 is reduced in diameter to some extent by moving the tapered surface 101c to the tip 101a. The Therefore, the restoring force (diameter reduction force) when snap-fitted from the tip 101a of the fitting tube portion 101 into the annular groove 2a of the shaft 2 is reduced, and a seal made of a synthetic resin material having a high elastic modulus such as PEEK. It is possible to effectively prevent the split end portions 3c and 3d of the ring 3 from colliding with force and breaking.

  In addition, since the fitting cylinder portion 101 can have at least the outer diameter on the enlarged diameter guide portion 102 side, in other words, the outer diameter of the large-diameter cylindrical surface 101b, it is necessary to maintain the strength. Thickness can be secured.

It is a semi-sectional view showing a partial cross section of a preferred embodiment of a seal ring mounting jig according to the present invention. FIG. 2 is a half cross-sectional view showing a usage state of the seal ring mounting jig of FIG. 1. It is a fragmentary sectional view which shows the mounting state of the synthetic resin seal ring. It is the figure which looked at the seal ring made from a synthetic resin from the direction parallel to an axial center. It is a half cross-sectional view showing a conventional seal ring mounting jig.

Explanation of symbols

2 shafts (parts subject to seal ring installation)
2a annular groove 3 seal ring 100 seal ring mounting jig 101 fitting tube portion 101a tip 101b large diameter cylindrical surface 101c taper surface 102 enlarged diameter guide portion 103 introduction portion

Claims (1)

In a mounting jig for mounting a synthetic resin seal ring divided in one circumferential direction in an annular groove formed on the outer peripheral surface of a seal ring mounting target part, the fitting is fitted on the outer periphery of the seal ring mounting target part. A fitting cylinder part whose tip can reach the outer peripheral position of the annular groove in the fitted state, and extending from the fitting cylinder part to the side opposite to the tip and the outer peripheral surface of the fitting part A diameter-increasing guide portion that gradually increases in diameter toward the joint tube side, and gradually decreases in diameter toward the tip on the outer peripheral surface of the fitting tube portion, and the seal ring is contracted by its own restoring force. A seal ring mounting jig characterized in that a taper surface slidable while being formed is formed , and an inclination angle of the taper surface is 10 to 30 ° .

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