JPH0120314B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vane type rocking motor, and more particularly to a shaft sealing mechanism in a vane type rocking motor.

[Prior Art] A vane-type swing motor configured as shown in FIG. A shaft 8 that projects out of the motor body 1 from the blade plate 7 and the shaft insertion hole 4
A vane-type swing motor is already known, which consists of a vane 6 equipped with a vane 6 and which swings the vane 6 by supplying and discharging pressure fluid to the pressure chamber 2 between the vane plate 7 and the stopper 3. be.

In such a vane type swing motor, as shown in FIG. 3, the motor main body 1 and the vane 6
is sealed between the shaft insertion hole 4 and a sealing member 9 made of an elastic material such as synthetic rubber attached to the shaft 8, and is also sealed by an O-ring 10. In particular, the shaft 8 The sealing member 9 is brought into pressure contact with the inner surface of the shaft insertion hole 4 of the motor body 1 over a relatively wide surface necessary for sealing. Therefore, the frictional resistance between the inner surface of the shaft insertion hole 4 and the sealing member 9 increases, and since the sealing member 9 is made of an elastic material such as synthetic rubber, it is difficult to obtain accurate finished dimensions. However, variations in characteristics occur, and the motor cannot be operated stably unless the fluid pressure supplied to the motor body is increased.

[Problems to be Solved by the Invention] The present invention enables reliable sealing between the shaft insertion hole of the motor body and the sealing member of the shaft in a small sealing area, thereby reducing friction on the sealing surface. The problem to be solved is to make the vane type swing motor swingable with low fluid pressure.

[Means for Solving the Problems] The present invention provides the above-mentioned vane type rocking motor, in which an annular protrusion and an annular groove adjacent thereto are provided on the inner surface of the shaft insertion hole from the pressure chamber side,
The above-mentioned protrusions are brought into pressure contact with the sealing member mounted on the shaft, and the grooves are kept in a non-contact state with respect to the sealing member, thereby solving the above-mentioned problems.

[Operation] A narrow protrusion in the axial direction provided on the inner surface of the shaft insertion hole of the motor body presses against the sealing member of the shaft, and a portion of the sealing member is pressed into the concave strip adjacent to the protrusion. Because of this, the motor body and shaft are sealed in a narrow area, and the frictional resistance between them is also reduced.

[Embodiment] The present invention is a vane-type swing motor having the basic configuration as shown in FIG. 2 described above, in which the shaft seal mechanism is improved.

To provide a supplementary explanation of the configuration of the vane-type swing motor shown in FIG. Locking holes 14, 14 are provided at eccentric positions in the pressure chamber 2, and by fitting the locking protrusions 15, 15 of the stopper 3 into the locking holes 14, 14, the pressure chamber 2
Stopper 3 is installed inside.

The vane 6 has a vane cylindrical portion 17 on which the vane plate 7 is fixed on the shaft 8, and this vane cylindrical portion 17 is attached to a sealing material 18 provided on the stopper 3.
A shaft 8 is brought into airtight and slidable contact with the motor body 1 and has seal members 9 on both ends thereof, and is projected to the outside of the motor body 1 through a bearing 19 fitted in the shaft insertion hole 4.

Although not shown, ports for supplying and discharging pressure fluid are provided on both sides of the stopper 3 in the motor body 1, respectively.

In the vane-type swing motor having such a configuration, the shaft insertion hole 4 of the motor body 1 has an annular protrusion 21 and an annular protrusion 21 on its inner surface from the pressure chamber 2 side, as shown in detail in FIG. Annular grooves 22 are provided adjacent to each other, and the protrusions 21 are pressed into contact with the sealing member 23 attached to the shaft 8 in a pressed state, and in this state, the grooves 22 are pressed against the sealing member 23. are in contact.
The protrusion 21 has a narrow width in the axial direction of the shaft 8, and locally presses against the planar sealing member 23 to the extent that it creates a recessed portion as shown in the figure, thereby providing effective sealing. Moreover, since the contact area is relatively small, the seal member 23
The frictional force between the two becomes very small. The sealing member 23 is formed into an annular shape with a square cross section, and does not require particularly high dimensional accuracy.

Furthermore, the groove 2 in the shaft insertion hole 4
2 has a diameter larger than that of the protrusion 21,
A sealing surface 24 that is sealed by the above-mentioned O-ring 10 is provided, and furthermore, a bearing insertion portion 25 into which the above-mentioned bearing 19 is fitted is formed on the shaft end side of the sealing surface 24.

In the above embodiment, the vane plate 7 is formed by covering the outer periphery of the core metal fixed to the vane columnar part 17 with a flexible material 26 such as synthetic rubber. It is also possible to mold the sealing member 23 and the sealing member 23 integrally.

In such a vane-type swing motor, when pressure fluid is supplied and discharged from ports (not shown) formed on both sides of the stopper 3 of the motor body 1, the vanes 6 swing within the pressure chamber 2. However, when the vane 6 swings, the shaft 8
The protrusion 21 on the inner surface of the shaft insertion hole 4 of the motor body 1 presses against the sealing member 23 of the motor body 1 in a pressed state and seals between the two, so that the pressure fluid supplied to the pressure chamber 2 flows into the pressure chamber. 2 is effectively prevented from leaking. In addition, since the above-mentioned seal portion has a narrow width in the axial direction, the seal is reliable, but the frictional force between the sealing surfaces is small, and therefore the frictional resistance against the swinging of the vane 6 is small. Even if the pressure of the fluid is relatively low, the vane 6 can swing without any problem.

[Effects of the Invention] In the present invention, when the shaft is inserted into the shaft insertion hole of the motor body, the narrow protrusion in the axial direction on the inner surface of the shaft insertion hole is pushed into the sealing member to effectively seal the shaft. Also, since a part of the sealing member escapes into the annular groove adjacent to the protrusion, the sealing area between the motor body and the shaft is small, and the frictional resistance between the two is small, so that low-pressure fluid cannot be used. The vane can be driven without any trouble.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of a main part of an embodiment of the present invention;
FIG. 2 is a longitudinal sectional front view showing the basic configuration of a vane type swing motor, and FIG. 3 is an enlarged sectional view of a conventional sealing mechanism. 1... Motor body, 2... Pressure chamber, 3... Stopper, 4... Shaft insertion hole, 6... Vane, 7
... Feather plate, 8 ... Shaft, 9, 23 ... Seal member, 21 ... Protrusion, 22 ... Concave strip.

Claims (1)

[Scope of Claims] 1. A motor body having a pressure chamber with a stopper and a shaft insertion hole, a vane having a blade plate inserted into the pressure chamber and a shaft protruding from the shaft insertion hole to the outside of the motor body. The motor body and the vane are sealed between the shaft insertion hole and a sealing member made of an elastic material attached to the shaft, which allows pressurized fluid to enter the pressure chamber between the vane plate and the stopper. In a vane-type swing motor that swings a vane by supplying and discharging air, an annular protrusion and an annular groove adjacent thereto are provided on the inner surface of the shaft insertion hole from the pressure chamber side, and the protrusion is 1. A shaft sealing mechanism for a vane-type swing motor, characterized in that the groove is in pressure contact with a sealing member attached to a shaft in a pressed state, and the groove is in a non-contacting state with respect to the sealing member.