JPS6159054B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sliding contact surface of a mechanical seal in an underwater motor, particularly for rotating a pump for pumping muddy water, by increasing the lubricating effect of oil. The purpose is to increase the durability of mechanical seals.

To explain the drawings of the embodiment, 1 is a motor shaft extending vertically from the motor chamber into the oil chamber 3 and led out to the axle box 2, and 4 is a motor shaft that is loosely connected to the motor shaft 1 and fitted into the hole edge of the boundary wall 5. The attached stationary side annular support 6 is a stationary side sliding ring supported by the support 4 and having a front end surface formed as a sliding surface 6a that is in contact with a sliding surface 7a of a rotating side sliding ring 7 described later. be. The rotating side sliding ring 7 is supported by the rotating side annular support 8 while being loosely engaged with the motor shaft 1, and as the motor shaft 1 rotates, the rotating side sliding ring 7 also rotates. The action of the pressing spring 9 maintains a watertight sliding contact between the sliding surfaces 6a and 7a.

Near the inner periphery of the opposing sliding surfaces 6a and 7a, the inner periphery of the rotating sliding ring 7 is eccentric from the axis of the motor shaft 1 as shown in FIG. 2A, or As shown in B, by providing a large diameter part in a part of the inner circumferential circle of the rotating side sliding ring 7, an intermittent contact surface 1 that communicates with the oil chamber 3 when the motor shaft 1 rotates is formed.
0 is formed. Further, in order to prevent muddy water from entering between the contact surfaces, the outer peripheral surfaces of both sliding rings 6 and 7 that come into contact with the pumped liquid are made to coincide concentrically.

When the motor shaft 1 rotates, an intermittent contact surface 10 that communicates with the oil chamber 3 is formed near the inner periphery of the contact surfaces of both the sliding rings 6 and 7, thereby providing lubrication between the contact surfaces of both the sliding rings. The effect is enhanced. That is, the third
As the motor shaft 1 rotates, the oil adhering to the surface 10a which is in a non-contact state at the position shown in Figure A is impregnated into the surface 10b which is in a contact state at the rotational position shown in Figure 3B, and is newly brought into a non-contact state. The oil adhering to the surface 10a' that has reached this condition also impregnates the surface 10b' that comes into contact at the rotational position shown in FIG. 3C, and oil is naturally replenished as the motor shaft 1 rotates. That's what happens. Note that even if the inner circumferential circle of the fixed side sliding ring 6 is made eccentric from the axis of the motor shaft 1, or a large diameter portion is provided in a part of the inner circumferential circle of the fixed side sliding ring 6, the above effect can be achieved. The effect is the same.

In conventional mechanical seals for submersible motors, the inner circles of the stationary sliding ring and rotating sliding ring are concentric and have the same diameter, allowing oil to be naturally supplied to the entire sliding surface as the motor shaft rotates. The sliding surface is simply kept lubricated by the oil that has been impregnated with it from the beginning. Therefore, the durability of the mechanical seal is poor, and replenishment of oil requires a special device with a complicated mechanism.

However, in the sliding contact surface of the present invention, an intermittent contact surface is formed as the motor shaft rotates, and oil is naturally replenished to the sliding surfaces of the stationary sliding ring and the rotating sliding ring. The lubricating effect can be maintained without the need for special equipment, and the durability of the mechanical seal can be significantly improved. Moreover, since the outer circumferential circles of both sliding rings remain concentric and have the same diameter, a structure that prevents the intrusion of external liquid is maintained, so there is an advantage that the sliding surfaces will not be worn out due to the intrusion of muddy water or the like.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional side view of a main part of a mechanical seal having a sliding contact surface according to the present invention, and FIGS. 2A and 2B are plan views illustrating aspects of the inner circumferential circle for forming an interrupted contact surface according to the present invention. , FIGS. 3A to 3C are explanatory diagrams showing the state of oil impregnation from the intermittent contact surface as the motor shaft rotates. 1... Motor shaft, 3... Oil chamber, 6... Fixed side sliding ring, 7... Rotating side sliding ring, 10... Intermittent contact surface.

Claims (1)

[Claims] 1. Between the contact surfaces of the rotating side sliding ring attached to the circumferential side of the motor shaft led out from the oil chamber and the stationary side sliding ring supported by a stationary body and playing with the motor shaft, By making the inner circumference of the rotating side sliding ring eccentric from the axis of the motor shaft, or by providing a large diameter part in a part of the inner circumferential circle of the rotating side sliding ring,
When the motor shaft rotates, an intermittent contact surface communicating with the oil chamber is formed near the inner periphery of the contact surfaces of both sliding rings, and the outer peripheral surfaces of both sliding rings are concentrically aligned. A sliding contact surface of a mechanical seal in an underwater motor, characterized by: