JPS60168970A - Packing having lip in utilization of shape memory alloy - Google Patents

Abstract

PURPOSE:To facilitate insertion of a packing and improve sealing effect by installing a shape memory alloy ring into which the shape for developing sealing effect is memorized previously, onto a lip. CONSTITUTION:In order to install a shape memory alloy ring 4 made of Ti-Ni alloy having a reverse-transformation temperature of about 70 deg.C onto a lip, the inside diameter of said ring 4 is expanded by about 1% or more at a room temperature and then fitted. A packing 1 having the ring 4 installed is accommodated into a sealing groove 5, and a rod 6 having an outside diameter of 90mm. is inserted. When the temperature of the fluid to be sealed is raised and the ring 4 is put into the reverse-transformation temperature or more, the inside diameter of the ring tends to contract to a memorized shape, and the packing 1 develops its sealing function effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in packings having lips, such as U-shaped packings, L-shaped packings, V-shaped packings, and soufflepers.

As seal packings for rotating shafts, reciprocating ronds, cylinders, etc., packings having lips made of rubber, plastic, metal, etc., and packings in combination with springs are used. A disadvantage of the packing having these lips is that the tightness decreases over time due to wear and permanent deformation, and the sealing effect decreases.

When used at high temperatures, the sealing effect and service life are further reduced.

To maintain the sealing effect, it is necessary to use heat-resistant packing, increase the tightness, and strengthen the spring. However, if this is done, it becomes difficult to insert the seal into the seal groove, and problems such as the lip of the seal becoming inverted tend to occur.

Therefore, in the present invention, a shape memory alloy ring, which has a diameter or shape memorized in advance to exhibit a sealing effect, is attached to or built into the lip. Thereby, the object is to provide a packing that is easy to insert into a seal groove and has a lip that has a large sealing effect.

The present invention will be described in detail below based on illustrated embodiments.

First, in the embodiment shown in FIGS. 1 and 2, 1 is:
It is a U-shaped gasket with an inner diameter of 89.8m, and 2 is the lip.

The material of this packing 1 is fluororubber, the hardness is 90°,
A mounting seat 3 is recessed in the inner surface of the lip 2. Conventionally, the tightening margin on the inner diameter side of the packing 1 is about 0.7 ml1, but this is set to 0 to 0.2 mm.

4 is a shape memory alloy ring made of a Ti-Ni alloy having a reverse transformation end temperature of approximately 706 C, and is preliminarily memorized to have a wire diameter of 1 ml and an inner diameter of 92 mm.

To attach this ring 4 to the mounting seat 3, ring 4
at 0°C to room temperature, and the inner diameter is approximately 1% or more (approximately 9381
) and then fit into place. To expand the ring,
This is done by pressurizing a jig (such as a tire) with hydraulic pressure.

In this way, the packing 1 with the ring 4 attached,
As shown in FIG. 2, it is sufficient to fit the rod 6 into the seal groove 5 and push in the rod 6 with an outer diameter of 90 mm.

When the temperature of the fluid to be sealed, such as lubricating oil, rises and the ring 4 reaches an advance of BWA degrees or higher (approximately 70 to 80"C), the inner diameter of the ring will try to contract to the memorized value of 92".
The seal 1 can effectively perform sealing.

In the test run, the rod 6 was reciprocated at approximately 0.5 m/sec at a hydraulic pressure of 30 kg/ci using C1-80ssSC heavy oil, and very good results were obtained.

Next, the embodiment shown in FIG. 3 is an embodiment in which a shape memory alloy ring is used for the souffle bar. 1' is a souffle bar made of filled Teflon.

2' is a lip, and a mounting seat 3' is provided on the inner surface. 4
' is T at the reverse transformation completion temperature of about 70'C, similar to the previous example.
An i-Ni alloy shape memory alloy ring that memorizes the dimensions of a wire diameter of 1 and an inner diameter of 35.7 fins. 7 is a rubber O-ring that seals the seal groove 5' side.

As in the previous embodiment, the inner diameter of the ring 4' is expanded at a temperature ranging from 0° C. to room temperature until it can be attached to the seal mounting seat 3' (36.6 mm or more), and then the ring 4' is mounted on the mounting seat 3' at room temperature. Thereafter, it is placed in the seal groove 5' together with the O-ring 7 (diameter 1.5 mm), and the rondro' (diameter 33 fins) is inserted.

The sealing is performed by the force that tends to shrink the ring 4' to its original diameter of 35.7++n when the temperature of the C heavy oil is raised to about 70 to 80'C.

In the test run, Londro' was reciprocated at approximately 100 m/sec, a stroke of 201 cm, and a heavy hydraulic pressure of 5 kg/cd, resulting in a good seal. Furthermore, when tightening with a conventional Q IJ song, a total tightening allowance of about 0°5 was required, and depending on the dimensional accuracy of the packing, the O-ring could come off when the rod was pushed in, but this example Now, an O-ring with a diameter of 1.5 can be sealed with a tightening of 0.2 fins,
It was inserted smoothly into the seal groove.

Contrary to the case of the rod seal mentioned above, in the case of a cylinder seal, if a shape memory alloy ring with a larger outer diameter or a shape memorized to exert a sealing effect is contracted and attached to the mounting seat in advance. However, the ring may be formed into a coil spring shape to facilitate contraction before installation.

Further, depending on the nature and shape of the seal and the state of the seal groove, a shape memory alloy ring may be attached to the lip as it is, with the diameter or shape memorized in advance to provide a sealing effect.

The shape memory alloy ring may be attached to the packing by combining the ring and the packing separately, or by fusing, adhering, or embedding it in the packing. The material of the packing is
Rubber, plastic, metal, and other sealing materials can be used.

[Brief explanation of the drawing]

Fig. 1 is an enlarged vertical sectional view of the main part showing an embodiment of the U-shaped gasket, and Fig. 2 is a longitudinal sectional view showing its use. Fig. 3 is a longitudinal cross-sectional view showing how the embodiment is used in a souffle bar. ...Shape memory alloy ring 5.5'...Seal groove 6.6'...Rod agent Patent attorney Masaharu Yamagami Figure 1 Figure 3 Procedural amendment April 26, 1985 Commissioner of the Japan Patent Office Manabu Shiga 1 Display of the case Packet with a lip using shape memory alloy 3 Person making the amendment Relationship with the case Patent applicant 4 Attorney 6 Number of inventions increased by the amendment None 7 Subject of the amendment "Detailed Description of the Invention" column and (2) Figure 2 is corrected as shown in the attached sheet.

Claims (1)

[Claims] 1 A bar 7 having a lip using a shape memory alloy, in which a shape memory alloy ring whose diameter or shape is memorized to exhibit a sealing effect is attached to or built into the lip.
Kin.