JPH041409Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial field of application) This invention is a device that is interposed between a first member and a second member that penetrates the first member and rotates relative to the first member, and This invention relates to improvements in sealing members that receive fluid pressure.

(Prior art) As a conventional sealing member, for example, the one shown in Fig. 3 is known (Utility Model No. 57-179649).
(see publication). In FIG. 3, 1 is a first member which is a part of a casing etc., a second member 2 which is a part of an output shaft etc. passes through this first member 1, and the second member 2 is a part of an output shaft etc. It is rotatably supported by one member 1, and a sealed chamber in which, for example, viscous fluid is sealed is formed between both members 1 and 2. First member 1 and second member
A seal member 3 is interposed between the first member 2 and the first member 2 to partition the sealed chamber. That is, the seal member 3 is fitted into a circumferential groove 4 formed in the inner peripheral wall of the first member 1. A pressure-receiving groove 5 is formed in the end surface (the right-hand end surface in FIG. 3) that receives the pressure of the viscous fluid among both end surfaces of the seal member 3, and this pressure-receiving groove 5 connects the seal member 3 with the first member side portion 6. It is divided into a second member side portion 7. Further, a deformation groove 8 is formed on the end surface of the seal member 3 on the opposite side exposed to the atmosphere (the left end surface in FIG. 3). And the bottom 5a of the pressure receiving groove 5
The height H from the first member side portion 6 to the end surface 6a and the height H from the second member side portion 7 to the end surface 7a are equal.

When the pressure P of the viscous fluid in the sealed chamber acts on the pressure receiving groove 5 through between both members 1 and 2, the pressure receiving groove 5 portion of the sealing member 3 is pushed by this pressure P;
At this time, the first member side portion 6 and the second member side portion 7 are subjected to pressure inward and outward in the radial direction with a projected area of height H,
They are equally pushed and expanded toward the outer circumferential side and the inner circumferential side, respectively, and seal the gap between the first member 1 and the second member 2.

(Problems to be solved by the invention) However, such conventional seal members 3
In this case, when the pressure P in the pressure receiving groove 5 increases, the first member side portion 6 and the second member side portion are separated depending on the projected area of the height H, although there is a difference in length in the circumferential direction. 7 were receiving pressure inward and outward in the rotational radial direction of the second member 2, the outer circumferential side of the first member side portion 6 came into pressure contact with the first member 1, and at the same time the inner circumferential side of the second member side portion 7 also came into contact with the second member 1. It was in pressure contact with member 2. Therefore, when the second member 2 rotates, the seal member 3 rotates together with the second member 2, and the outer peripheral side of the first member side portion 6 comes into sliding contact with the wall surface of the circumferential groove 4 of the first member 1. Ta. Therefore, even though the inner peripheral side of the second member side portion 7 should be in sliding contact, the first
Since the outer circumferential side of the member side portion 6 is in sliding contact, the circumferential speed of the outer circumferential side of the first member side portion 6 is faster than that of the inner circumferential side of the second member side portion 7, so that wear on the outer circumferential side is further accelerated. will be done. Further, the rotating seal member 3 has its deformed groove 8 side end surfaces 6b, 7.
b is pushed against the inner wall surface of the circumferential groove 4 by the pressure P of the viscous fluid in the pressure receiving groove 5 and comes into sliding contact with the inner wall surface of the circumferential groove 4, and there may be no lubrication between these surfaces. , wear of the deformed groove 8, especially the side end surface 6b, is accelerated. As a result, when the pressure P of the hydraulic oil in the pressure receiving groove 5 increases, the wear of the seal member 3 is accelerated and the durability of the seal member 3 is reduced.

Therefore, the object of this invention is to provide a sealing member that can improve durability.

(Means for Solving the Problems) In order to solve these problems, this invention includes a first member and a second member that is provided concentrically with the first member and is rotatable relative to the first member. a member, a circumferential groove formed in the first member, and a sealing member installed in the circumferential groove to partition a sealed chamber in which a fluid is sealed, the end face of the sealing member receiving pressure of the fluid. and a first member side portion and a second member side portion separated by the pressure receiving groove, and when the sealing member is not installed in the circumferential groove, the seal member has a pressure receiving groove formed in the circumferential groove. The height to the end surface of the second member side portion is lower than the height to the end surface of the first member side portion.

(Function) In the seal member according to this invention, the height from the bottom of the pressure receiving groove to the end surface of the second member side portion is lower than the height from the bottom of the pressure receiving groove to the end surface of the first member side portion. Therefore, the area projected from the pressure receiving groove toward the inner peripheral side of the second member side portion is smaller than the area projected from the pressure receiving groove toward the outer peripheral side of the first member side portion. Therefore, when the pressure of the fluid in the pressure receiving groove increases, the force that pushes the second member side portion toward its inner circumference is greater than the force that pushes the first member side portion toward its outer circumference due to the pressure of the fluid. is smaller. Therefore, the sealing member does not rotate together with the rotating second member, but is fixed to the first member and comes into sliding contact with the second member.

(Example) Hereinafter, an example of this invention will be described based on the drawings.

FIG. 1 is a diagram showing an embodiment of this invention.
First, the configuration will be explained. In FIG. 1, 11 is a casing as a first member in which a center hole 12 is formed, and a rotating shaft 13 as a second member is concentrically inserted (through) into this center hole 12. 13 is rotatably supported by the casing 11. Inside the casing 11 is a sealed chamber (not shown).
(located on the right side in FIG.
A plurality of resistance plates are provided which are respectively engaged with and arranged close to each other, and this sealed chamber is filled with a viscous fluid such as silicone oil, thereby forming a so-called viscous coupling spring. In order to prevent the enclosed viscous fluid from flowing out through the gap between the casing 11 and the rotating shaft 13 to the outside (to the left in FIG. 1), a sealing member 14 made of an elastic material is interposed in this gap. A seal member 14 is fitted into a circumferential groove 15 formed in the inner circumferential wall of the seal member 11 . The end face (first
A pressure-receiving groove 16 is formed on the right end surface in the figure, and the cross-sectional shape of the pressure-receiving groove 16 is such that its outer circumferential side is perpendicular to this end surface, and its inner circumferential side is a gentle curve that continues to the end surface. ing. The pressure receiving groove 16 allows the seal member 14 to connect the first member side portion 17 and the second member side portion 17.
When the seal is not installed, the height Ha from the bottom 16a of the pressure groove 16 to the end surface 17a of the first member side portion 11 is greater than the height Ha from the bottom 16a of the pressure groove 16 to the second member side. The height Hb of the portion 18 to the end surface 18a is small. Therefore, the area B projected from the pressure receiving groove 16 toward the inner peripheral side of the second member side portion 18 is smaller than the area A projected from the pressure receiving groove 16 toward the outer peripheral side of the first member side portion 17. It's summery. On the other hand, a deformation groove 19 having the same shape as the pressure receiving groove 16 is formed on the end face (left end face in FIG. 1) of the seal member 14 opposite to the end face receiving the pressure of the viscous fluid.

Next, the action will be explained.

When the viscous coupling spring rotates and the temperature and pressure of the viscous fluid increases, the casing 11
Fluid pressure P acts on the pressure receiving groove 16 from between the rotating shaft 13 and the rotating shaft 13, and due to the pressure P of the fluid in the pressure receiving groove 16,
The pressure receiving groove 16 portion of the seal member 14 is pressed. At the same time, the second member side portion 18 is pushed toward the inner circumference, and the first member side portion 17 is also pushed toward the outer circumference. The force pushing toward the inner circumference at this time
PB is smaller than the force PA pushing toward the outer circumference due to the difference in areas A and B. Therefore, when the pressure P of this fluid increases, the pushing force PA−PB
The first member side portion 17 is pressed against the outer periphery of the circumferential groove 15 more strongly than the second member side portion 18 by the difference. Therefore, when the rotating shaft 13 rotates, the seal member 1
4 is fixed to the circumferential groove 15 of the housing 11, and its inner peripheral side comes into sliding contact with the rotating shaft 13. The circumferential speed of the outer periphery of the rotary shaft 13 is slower than the circumferential speed of the outer circumferential side of the seal member 14 when the seal member 14 rotates together with the rotary shaft 13.
4 wear is suppressed. Further, since the seal member 14 is fixed to the circumferential groove 15, the deformed groove side end surface 20 of the seal member 14 on the atmosphere side is in pressure contact with the inner wall surface of the circumferential groove 15 without sliding contact. The end face 20 also does not wear out. As a result, even if the pressure P of the fluid in the pressure receiving groove 16 increases, the wear resistance of the seal member 14 is improved.

Note that this example is a case in which the first member is a rotating casing and the second member is a rotating shaft, but the same applies if either the first member or the second member is fixed. It acts on

Next, another embodiment in which the thickness l of the second member side portion 22 is smaller than the thickness L of the first member side portion 21 is shown in FIG. The height hb from the bottom 23a of the pressure groove 23 to the end surface 22a of the second member side portion 22 is lower than the height ha from the bottom 23a of the pressure groove 23 to the end surface 21a of the first member side portion 21. can be used and functions similarly to the above embodiment.

Further, although not shown in the drawings, the same effect as in the above embodiment can be obtained when the height of the end face of the sealing member on the deformation groove side is made uniform.

(Effect of the invention) As explained above, according to this invention, when the seal is not installed, the height from the bottom of the pressure groove to the end face of the first member side is lower than the height from the bottom of the pressure groove to the end face of the first member side. Since the height to the end face of the sealing member is reduced, the sealing member is fixed to the first member when fluid pressure is applied to the pressure receiving groove, and it is possible to prevent the sealing member from accelerating wear. As a result, the wear resistance of the seal member can be improved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the sealing member according to this invention, FIG. 2 is a cross-sectional view showing another embodiment of the sealing member according to this invention, and FIG. 3 is a cross-sectional view showing a conventional sealing member. It is a diagram. 11... Casing (first member), 13... Rotating shaft (second member), 14... Seal member, 16,
23...Pressure receiving groove, 16a, 23a...Bottom, 1
7, 21...first member side portion, 17a, 21a...
...End face, 18, 22...Second member side portion, 18
a, 22a...end surface.

Claims (1)

[Scope of utility model registration request] a first member, a second member that is provided concentrically with the first member and is rotatable relative to the first member; a circumferential groove formed in the first member; A sealing member that partitions an enclosed sealed chamber, the sealing member having a pressure-receiving groove formed in an end face receiving the pressure of the fluid, and a first member side portion and a second member side portion separated by the pressure-receiving groove. a member side portion, the height from the bottom of the pressure receiving groove to the end surface of the first member side portion to the end surface of the second member side portion when the seal member is not installed in the circumferential groove; A seal member characterized by being lowered.