JPS5925914Y2 - Mechanical seal for screen shaft - Google Patents

Description

[Detailed description of the invention] The present invention is based on a mechanical seal that seals the part where the rotating shaft of the sufnon passes through in a paper stock screening device.As shown in FIG. The porous hole is divided into a raw material inflow chamber 2 and a passed raw material receiving chamber 3 by a recessed member, and a rotary shaft 4 is inserted through the center of the tank bottom so that the upper end protrudes into the raw material inflow chamber 2, and the upper end of the rotary shaft 4 is The output of the motor 6 is transmitted to the rotating shaft 4 by a transmission mechanism consisting of a large pulley 7, a power belt 8, and a power sheep 9 to rotate the screen rotor 5, and also to rotate the screen rotor 5 from the raw material inlet chamber 10 to the raw material inflow chamber. 2, the raw material is filtered by the screen cylinder 12 while avoiding clogging of the screen surface of the screen cylinder 12 by the action of the blades 11 of the screen rotor 5, and passes through the screen cylinder 12. In a screen device that discharges the raw material that has flowed into the raw material receiving chamber 3 from the raw material outlet 13 and discharges a part of the raw material that has not passed through the screen cylinder 12 from the bottom of the raw material inlet chamber 2, the rotating shaft penetrating portion at the bottom of the tank is used. In this seal, a dome-shaped seal housing 14 with a through hole at the top is connected to the rotating shaft 4.
The seal housing 1 is provided so as to cover the opening 15 of the tank bottom plate through which the intermediate portion of the seal housing 1 is penetrated, and the upper end portion of the rotating shaft 4 is penetrated.
4 is sealed with a mechanical seal.

A conventional sealing device for sealing the rotating shaft through-hole of the seal housing 14 has a flat friction surface 1 as shown in FIG.
6, the thrust bearing 18 on the stationary side is prevented from rotating by a rotation stopper pin 19, and is loosely inserted into the rotation shaft through hole 20 of the seal housing 14. The thrust bearing 17 on the rotating side is fitted with a rotation stopper pin 2 in an annular groove 22 provided in a snob 21 fitted on the rotating shaft 4.
3 is fitted so as to rotate together with the sleeve 21 and is located above the fixed side thrust bearing 18, and the fixed side thrust bearing 18 is connected to the spring 2.
4 on the rotating side thrust I/bearing nong 17, and sealing nongs 25 and 26 are arranged between the through hole 20 and the fixed side thrust bearing 18 and between the annular groove 22 and the rotating side thrust bearing 17. By providing this, a seal can be established between the rotating shaft 4 and the through hole 20.

When the screen rotor 5 is rotated in the above manner, the water level of the raw material in the tank becomes lower at the center than at the periphery as shown by the imaginary line 27, and the thrust bearings 17 and 18 rise above the water surface, causing the friction surface 16 to dry. As a result, the frictional resistance between the thrust bearings 17, 18 increases, causing severe wear and heating, so conventionally the thrust bearings 17, 18 are cooled and the friction surfaces 16 are lubricated.

However, in the past, water was continuously supplied to a chamber 28 provided at the bottom of the tank, and the water in the chamber 28 was forced into the seal housing 14 and rose between the thrust bearing 18 on the fixed side and the sleeve 21. A groove 29 is formed inside the friction surface 16 by the thrust bearing 17 and 18 from the air gap.
The water in the groove 29 is pushed out to the friction surface 16 for lubrication and cooling, and the thrust bearing 17
．． If foreign matter is mixed into the water that reaches the temperature of 18, the friction surface 16 is rapidly worn down and the sealing function is lost, which is a disadvantage.

The present invention was made to eliminate the above-mentioned drawbacks and provide a mechanical seal for the screen shaft with excellent lubrication and cooling effects. In a mechanical seal for a screen shaft in which a thrust bearing is provided and a stationary thrust bearing that presses against the rotating thrust bearing is provided in the rotating shaft through-hole, water is injected between the two thrust bearings from outside the thrust bearing. It is characterized by being equipped with an injection device that

Embodiments of the present invention will be described below with reference to the drawings.

3 and 4 show an example of the present invention, in which the seal in the through hole 20 of the seal housing 14 through which the rotating shaft 4 of the screen rotor passes is inserted into the thrust bearing 17 on the rotating side, as shown in FIG. 2. In this structure, a pool wall 31 is provided all around the outer edge of the through-hole type acid part 30 of the seal housing, and the pool 3 is formed on the through-hole type acid part 30.
form 2.

The pool wall 31 has a plurality of injection ports 33 opening between the two thrust bearings 17 and 18, and a flow path 3 connected to the injection ports 33.
4, and the annular flow path 35 communicates with a pipe 37 via a communication flow path 36 provided in the seal housing.

The pipe 37 communicates with a water supply source via a pressure gauge 38 and a flow control valve 39.

In FIG. 3, 40 indicates a tank bottom plate, 41 and 42 indicate bearings, and the same reference numerals as in FIGS. 1 and 2 indicate the same members.

In this embodiment, when the screen rotor 5 is rotated, the flow rate control valve 39 is opened to direct water from the pipe 37 to the flow path 36.
．． 35, 34, and the injection port 33 injects between both thrust bearings 17, 18.

The thrust bearing is cooled by the water injected from the injection port 33, and a portion of the water enters the friction surface 16 of the thrust bearing to lubricate it.

The water discharged from the injection port 33 accumulates in the pool 32, and eventually overflows from the pool 32 and falls into the tank 1.

The water injection pressure is adjusted by an operator checking the pressure gauge 38 and appropriately changing the opening degree of the flow rate control valve 39.

In the above-mentioned embodiment, a pool was formed in the through-hole acid part of the rotating shaft so that water could be injected from the pool wall to the thrust bearing. The present invention, which may be implemented by spraying water, has the above-described configuration, and since lubricating and cooling water is not introduced inside the thrust bearing, even if foreign matter gets mixed into the water, the friction surface will not be damaged. It has the advantage of being able to maintain excellent lubrication and cooling effects without the need for a filter for the cooling water.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the screen processing device, Fig. 2 is an explanatory diagram of a conventional mechanical seal for the screen shaft, Fig. 3 is an explanatory diagram of the present invention, and Fig. 4 is an explanatory diagram of the water injection device in the present invention. be. 1... Tank, 4... Rotating shaft, 5...
... Screen rotor, 14 ... Seal housing, 16 ... Friction surface, 17 ... Rotating side thrust bearing, 18 ... Fixed side thrust bearing , 20...Rotating shaft through hole, 3
1...pool wall, 33...spout, 3
7...Piping, 39...Flow control valve.

Claims (1)

[Scope of utility model registration request] A mechanical seal for a screen shaft, in which a rotating side thrust bearing is provided on the protrusion in the tank of a rotating shaft that extends through the bottom of the tank, and a stationary side thrust bearing that presses against the rotating side thrust bearing is provided on the rotating shaft through-hole. A mechanical seal for a screen shaft, characterized in that it is equipped with an injection device that injects water between both thrust bearings from the outside of the thrust bearing.