JPH0318782Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a packing that can be easily installed with a low assembly load and that can provide stable sealing performance.

(Prior Art) As this type of gasket, those shown in FIGS. 7 to 9 are known. That is, FIGS. 7 to 9 are cross-sectional views showing various conventional packings. The packing 101 shown in FIG. The seal portion 10 is stored between
2b comes into contact with the annular surface 106 of the case 105 to perform a sealing action. The sealing portion 202b of the packing 201 shown in FIG. 8 is curved and comes into contact with the annular surface 206 of the case 205 to perform a sealing action, and the packing 3 shown in FIG.
01 is specifically constituted by an O-ring, which performs a sealing action by being compressively deformed between the annular surface 306 of the case 307 and the stem 308 as shown in the figure. In addition, each of the above packskin 1
01, 201, and 301 are all integrally formed of an elastic material such as nitrile rubber.

(Problems to be Solved by the Invention) However, in the case of the above-mentioned gaskets 101 and 201, as shown by broken lines in FIGS. Therefore, these seal portions 102b,
There is a problem in that a wavy gap occurs in 202b, and the desired sealing effect cannot be expected. Further, the packing 301 made of an O-ring shown in FIG. 9 has a disadvantage in that it must be deformed under pressure under a high load in order to maintain the sealing effect.

The present invention was developed in view of the above-mentioned conventional problems.The purpose of this invention is to be able to easily install it with a low assembly load, absorb the variation in dimensions of the mating part, and to be able to install it reliably and stably. It provides a seal that can maintain high sealing performance.

(Means for Solving the Problems) In order to achieve the above object, this invention consists of an annular surface formed toward the outer diameter side from the fitting circumferential surface of the case into which the small diameter portion of the stem is fitted; It is an annular packing that is installed between the stepped part provided at one end, and the one end of the bent part made of rubber-like elastic material has a fixed part that is thicker than the bent part and is attached to the small diameter part of the stem. The packing is characterized in that a seal portion is provided at the other end to contact the annular surface, and a ring having higher rigidity than the seal portion is fixed to the side surface of the seal portion.

(Function) Therefore, the rigidity of the seal portion that contacts the annular surface of the case is increased by the ring, so that
When the seal is assembled, the seal portion does not sink in, and its sealing performance is maintained stably and at a high level. In addition, since the bent part is elastically deformed by a predetermined load received from the annular surface, the reaction force should ensure the contact surface pressure of the seal part with the annular surface, and the stem can move freely in the axial direction. be. Therefore, variations in case dimensions can be effectively absorbed,
Moreover, it can be easily installed with a low assembly load.

(Example) An example of the present invention will be described below based on the accompanying drawings.

Fig. 1 is a half-cut sectional view of the packing according to the present invention;
Figure 2 is a half-cut sectional view showing the assembled state of the packing.
3a, b, and c are half-cut sectional views for explaining the deformation process of the packing, and FIG. 4 is a graph showing the relationship between the load and the amount of compression of the packing.

The packing 1 shown in FIG. 1 has a main body 2 formed into a cylindrical shape from an elastic material such as nitrile rubber. A thick fixing portion 2a that comes into contact with the small diameter portion 51 and step portion 52 of the stem 4 fitted within the circumferential surface 50
The lower end portion constitutes a sealing portion 2b, and between the fixed portion 2a and the sealing portion 2b, there is a bent portion (thinner than the fixed portion 2a) 2c that elastically deforms under a predetermined load as described later. Continuously formed.
A ring (specifically, an O-ring) 3 made of a material having a higher rigidity than the elastic material constituting the main body 2 is baked onto the outer periphery of the seal lip portion 2b of the main body 2. ing.

As shown in FIG. 2, the gasket 1 is attached and held between the stepped portion 52 of the stem 4 and the annular tapered surface 53 of the case guide 5.
In the illustrated assembled state, the bent portion 2c is the tapered surface 5.
The seal portion 2b is elastically deformed in response to the assembly force Ρ from the case 5, and is pressed against the tapered surface 53 of the case 5 to perform a sealing action. At this time, since the rigidity of the seal part 2b is increased by the ring 3 constituted by an O-ring, the seal part 2b will not be easily deformed during assembly, and the wavy gap caused by the seal part 2b will not be easily deformed. This is prevented, the sealing performance is maintained stably and at a high level, and leakage of grease from the direction of arrow a in the figure and intrusion of dust from the direction of arrow b in the figure are effectively prevented. Moreover, the seal portion 2b
As a result of increasing the rigidity of the packing 1, the bent portion 2c of the packing 1 is elastically deformed, so that the reaction force can ensure the contact pressure of the sealing portion 2b against the tapered surface 53, and Can move. Therefore, variations in the dimensions of the case 5, which is the mating component, can be effectively absorbed, and the packing 1 can be reliably attached and held with a low assembly load. Furthermore,
As a result of the bending portion 2b being elastically deformed as shown in FIG. 53, the sealing performance of the seal portion 2b is further improved.

Here, the relationship between the deformation of the packing 1 and the load will be mentioned based on FIGS. 3 and 4.
If the load acting on the packing 1 is Ρ = 0, the amount of deformation (amount of compression) δ = 0 (the fourth
The state of the gasket 1 at this time is shown in FIG. 3a (same as FIG. 1), and no deformation occurs in the gasket 1. After that, if the applied load Ρ is gradually increased, the amount of deformation δ of the seal 1 increases in proportion to the increase in this load Ρ, as shown in Figure 4, but when this load Ρ is Ρmax (point B in Figure 4)
), the amount of deformation increases, but conversely the load (that is, the load to be borne by the packing 1) rapidly decreases, and from this point the bent portion 2c of the packing 1 begins to undergo elastic deformation. 3b shows the state of the packing 1 just before elastic deformation occurs in the bent portion 2c, and FIG. 3c shows the state of the packing 1 when the bent portion 2c undergoes elastic deformation. Therefore, the packing 1 has a relatively low load Ρ=
If Ρmax is applied, elastic deformation occurs in the bent portion 2c, so that the packing 1 can be easily installed with a resisting assembly load.

Next, modified embodiments of the present invention are shown in FIGS. 5 and 6, and each of the gaskets 11 and 21 shown in these figures has its seal portions 12b and 22b.
Ring 1 made of metal or resin with a rectangular cross section
3 and 23 are baked on, and both gaskets 11,
21 differs only in the shape of the bent portions 12c and 22c, and both have the same functions and effects as described in the first embodiment.

(Effects of the invention) As is clear from the above explanation, according to the invention, a bent part that is elastically deformed under a predetermined load is continuously formed between the fixed part of the packing and the seal part, and the seal part is Since the ring is fixed to the side surface, the rigidity of the seal part is increased by the ring, and it does not easily deform, and when the seal is assembled, the seal part is prevented from digging in, and its sealing performance is improved. This has the effect of keeping the temperature stable and high. Furthermore, according to the present invention, the bent portion of the packing elastically deforms under a predetermined load, so it is possible to effectively absorb variations in dimensions of the mating parts, and the packing can be easily installed with a low assembly load. You can get the effect that you can.

[Brief explanation of the drawing]

Fig. 1 is a half-cut sectional view of the packing according to the present invention;
Figure 2 is a half-cut sectional view showing the assembled state of the packing, Figures 3 a, b, and c are half-cut sectional views to explain the deformation process of the packing, and Figure 4 is the load and compression amount of the packing. A graph showing the relationship between
FIG. 6 is a half-cut sectional view of a packing according to a modified embodiment of the present invention, and FIGS. 7 to 9 are partial sectional views showing conventional packing. Explanation of codes, 1, 11, 21... Patsukin, 2
...Body, 2a...Fixed part, 2b, 12b, 22
b... Seal part, 2c, 12c, 22c... Bent part, 3, 13, 23... Ring.

Claims (1)

[Scope of utility model registration request] It is an annular packing that is installed between an annular surface formed from the fitting circumferential surface of the case into which the small diameter portion of the stem is fitted toward the outer diameter side, and a stepped portion provided at one end of the small diameter portion. A fixing part that is thicker than the bent part and attached to the small diameter part of the stem is provided at one end of the bent part made of a rubber-like elastic material, and a sealing part that contacts the annular surface is provided at the other end. A seal characterized by a ring that is more rigid than the seal part fixed to the side of the seal part.