JPS6229724Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a mechanical seal, and its purpose is to prevent slurry from clogging between the shaft packing and the shaft, causing leakage due to the slurry.
It is an object of the present invention to provide a mechanical seal that can remove slurry without causing smooth axial movement of a moving ring and deterioration of the sealing effect.

Hereinafter, as an example, the configuration will be described in the case where the present invention is applied to a pump. 1 is a pump casing, 2 is a shaft, 3 is an impeller attached to the shaft end, and 4 is a fixed ring fixed to the inner circumference of the casing, which is attached to the lid of the casing 1 via a buffer ring 5.
Reference numeral 6 denotes a rotating ring that rotates together with the shaft 2, and is fixed on the shaft 2 by a key 7. A movable ring 8 is rotatably fitted onto the shaft 2 via a shaft packing 9 between the fixed ring 4 and the rotating ring 6, and has an engaging piece 10 that engages with the rotating ring 6. A spring 11 provided between the fixed ring and the fixed ring is applied to keep the fixed ring in constant contact with the fixed ring. As the shaft packing 9, an O-ring, a U-ring, a V-ring, etc. are usually used. Reference numeral 12 indicates a sliding contact surface between the movable ring 8 and the shaft, and 13 indicates a contact surface between the movable ring 8 and the fixed ring 4. The movable ring 8 is fitted onto the shaft via the shaft packing 9, and the engagement piece It rotates together with the rotating ring 6 via the ring 10, and is constantly pressed in the direction of the stationary ring 4 by the spring 11, making close contact with it and sliding against the contact surface 13, so that it is tightly sealed and completely sealed. The feature of the present invention is that in the movable ring 8, the movable ring 8
A circumferential groove 14 is formed on the sliding contact surface 12 between the shaft 2 and the shaft 2 at a position closer to the liquid (rotating ring side) than the shaft packing 9, and one or more holes 15 are formed that penetrate from this groove 14 to the outside. This is the point.

In the present invention, by forming the grooves 14 and holes 15 as described above, slurry can be concentrated in the grooves 14 due to the centrifugal force generated at the inner peripheral edge of the grooves 14 when a pump or the like is driven, and can escape through the holes 15 and be discharged together with water. It became like that. Therefore, defects such as slurry clogging between the shaft packing 9 and the shaft 2 are eliminated, and a drop in sealing effect can be prevented without interfering with liquid leakage or movement of the movable ring in the axial direction due to the slurry. Summer.

As shown in FIG. 3, the engagement piece 10 of the movable ring 8
Normally, the portion is configured to engage with the engagement piece 16 of the rotating ring 6 and rotate with the rotation of the rotating ring 6, but when a relatively large through hole 16 is formed in this engagement piece 10, Slurry generated in the spring 11 portion can be discharged from this through hole,
Together with the grooves 14 and holes 15 formed on the sliding contact surface 12 of the movable ring, the slurry removal effect is increased, and the center of gravity of the movable ring 8 can be set closer to the fixed ring 4, resulting in improved driving stability. is obtained, and the sealing effect can be improved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a pump to which the present invention is applied, Fig. 2 is a plan view of the main parts showing the state of engagement between the rotating ring and the movable ring, and Fig. 3 is an exploded perspective view of the vicinity of the shaft. . 1... Casing, 2... Shaft, 4... Fixed ring,
6... Rotating ring, 8... Moving ring, 9... Shaft packing, 10... Engaging piece, 11... Spring, 12
...Sliding contact surface, 14... Groove, 15... Hole, 16
...through hole.

Claims (1)

[Claims for Utility Model Registration] (1) A fixed ring fixed to the casing, a rotating ring rotating together with the shaft, and a shaft packing inserted between the fixed ring and the rotating ring, which is rotatably fitted onto the shaft and engaged with the rotating ring. A mechanical seal consisting of a movable ring which has an engaging piece and a movable ring which is always urged by a spring provided between the rotary ring and the fixed ring so as to be in contact with the fixed ring, the movable ring having a sliding contact surface with the shaft. A mechanical seal characterized in that a circumferential groove is formed at a position on the liquid side of the shaft packing, and a movable ring is incorporated therein having one or more holes passing through the groove to the outside. (2) The mechanical seal according to claim 1 of the utility model registration, wherein a through hole is formed in the engaging piece of the movable ring that engages with the rotating ring.