JPH0624612Y2 - Shaft seal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a shaft sealing device in which a rotary shaft of a machine body such as a pump is sealed by a mechanical seal.

[Prior Art] Conventionally, in this type of shaft seal device, as shown in FIG. 2, a sleeve liner (3) is provided around the circumference of a rotating shaft (2) inserted in a machine body (1). When incorporating the mechanical seal (4), a seal cover (7) attached to the machine body (1) via bolts (5) and nuts (6).
While incorporating a stationary side seal portion composed of a seal ring (10) fixed via an O-ring (8) and a knock pin (9) into the inner diameter portion (71) of the rotary shaft (2), Collar (11), coil spring (12),
Compression ring (13) and packing (14)
A rotary side seal part composed of a mating ring (15) fixed via the above is incorporated, and the mating ring (15) of the rotary side seal part is elastically attached to the seal ring (10) of the stationary side seal part. A pressure-sliding contact is made to form a mechanical seal by the stationary side seal part and the rotary side seal part, and the seal cover (7) is provided with a quenching hole (16) communicating with an inner diameter part (71) thereof, In some cases, quenching is performed by injecting and discharging the cooling fluid (W) into the stationary side seal portion from the quenching hole (16).

[Problems to be Solved by the Invention] However, in the shaft sealing device having such a conventional structure, the cooling effect by quenching is mainly the stationary side seal portion of the mechanical seal, and the rotating side seal which is the operating side. The effect on the department is small. Ie sleeve liner (3)
Outer peripheral surface of the tip part (3a) and mating ring (1
Since the cooling effect of a part of the cooling fluid (W) that has entered the front surface of the packing (14) through the gap between the inner peripheral surface of (5) and the inner peripheral surface is small, the packing (14) of the rotating side seal part is not affected by heat transfer or the like. When exposed to a high temperature, there is a problem that malfunction of the packing (14) is likely to occur due to curing or the like.

[Purpose of Invention] The present invention has been made under the above circumstances, and its purpose is not only to quench the stationary side seal portion of the mechanical seal but also to cool the rotating side seal portion. An object of the present invention is to provide a shaft sealing device that can be raised.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention seals the shaft circumference of a rotary shaft inserted in a machine body with a mechanical seal, and the mechanical seal is attached to the machine body. A stationary side seal part, which is assembled and fixed in the inner diameter part of the sealed cover, and a rotating side, which is provided on the outer circumference of a sleeve liner mounted around the axis of the rotary shaft via a packing and is in sliding contact with the stationary side seal part. A shaft sealing device comprising a seal portion, wherein the seal cover is provided with a quenching hole for injecting and discharging a cooling fluid from the stationary seal portion side to the inner peripheral space thereof, wherein the outer peripheral surface of the rotating shaft is At the position corresponding to the inner peripheral side of the packing, a step portion having a smaller diameter on the stationary seal portion side is formed, and the tip end portion of the sleeve liner extends from the outer periphery of the step portion of the rotary shaft to the inner periphery of the stationary seal portion. A space portion protruding toward the space and having a space into which the cooling fluid from the quenching hole can flow is formed between the inner peripheral surface of the tip portion and the outer peripheral surface of the small diameter portion of the rotating shaft. It is a thing.

[Operation] That is, according to the present invention, with the above configuration,
The tip of the sleeve liner, which protrudes from the outer circumference of the step portion of the rotary shaft toward the inner peripheral space of the stationary side seal portion, has a space between the inner peripheral surface of the tip portion of the sleeve liner and the outer peripheral surface of the small diameter portion of the rotary shaft. It is significantly cooled by the cooling fluid flowing from the quenching hole side. Therefore, the packing mounted on the outer circumference of the sleeve liner is cooled via this sleeve liner.

[Embodiment] Hereinafter, the present invention will be described in detail with reference to an embodiment shown in FIG. In the illustrated embodiment according to the present invention, the same parts as those of the conventional device shown in FIG.

That is, according to the present invention, as shown in FIG. 1, the rotary shaft (2) at a position corresponding to the rotary side seal portion of the mechanical seal.
Is formed in a stepped manner so that the seal cover (7) side has a small diameter, and the sleeve liner (3) fitted around the rotary shaft (2) is fitted to the seal ring (1) of the stationary side seal portion.
It has been extended to the middle of 0). That is, the sleeve liner (3) extends from the inner peripheral position of the packing (14) that seals the inner periphery of the mating ring (15), which is the rotating side seal part, to the inner periphery of the seal ring (10), which is the stationary side seal part. The tip portion (3a) reaching the space projects from the outer circumference of the step portion (2a) of the rotary shaft (2) to the outer circumferential space on the side of the small diameter portion (2b), whereby the tip end portion (3) of the sleeve liner (3).
A space (17) is formed between the inner peripheral surface of (a) and the outer peripheral surface of the rotating shaft (2), and a quenching hole (16) provided in the seal cover (7) is formed in the space (17). ), The cooling fluid (W) is allowed to flow in.

Therefore, according to the present invention, with the above structure, the cooling fluid (W) injected from the quenching hole (16).
In addition to the quenching effect of the stationary side seal part of the mechanical seal, the space part (17) formed between the rotary shaft (2) and the sleeve liner (3) at the position corresponding to the rotary side seal part is cooled. By allowing the fluid (W) to flow in, the packing (14) of the rotation side seal portion can be cooled.

This is because the tip portion (3a) of the sleeve liner (3) extends from the outer circumference of the step portion (2a) of the rotary shaft (2) to the small diameter portion (2b).
Since it projects to the outer peripheral space on the side, the contact area with the cooling fluid (W) is large and the cooling is significantly performed, so that the packing (1
In addition to the cooling action by the cooling fluid (W) that has entered the gap between the outer peripheral surface of the tip portion (3a) of the sleeve liner (3) and the inner peripheral surface of the mating ring (15), 4) This is because the liner (3) is cooled by the tip portion (3a).

[Effects of the Invention] As is clear from the above description, according to the present invention, since the tip end of the sleeve liner is separated from the outer peripheral surface of the rotating shaft, the contact area with the cooling fluid increases and the outer circumference of the sleeve liner increases. Since the packing of the mounted seal on the rotary side is effectively cooled through this sleeve liner, it is possible to reliably prevent the malfunction of the packing due to hardening of the seal on the rotary side as in the past. It has an excellent effect of being able to.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an essential part showing an embodiment of a shaft sealing device according to the present invention, and FIG. 2 is a schematic sectional view of an essential part of a conventional shaft sealing device. (1) ...... Airframe, (2) ...... Rotation axis, (3) ...... Sleeve liner, (4) ...... Mechanical seal, (7) ...... Seal cover, (71) ...... Inside diameter part, (10) ...... Still side seal part (seal ring), (14) ...... Packing, (15) …… Rotary side seal part (mate ring), (16) …… Quenching hole, (17) …… Space part, (W) ... Cooling fluid.

Claims (1)

[Scope of utility model registration request] 1. A stationary-side seal portion formed by mechanically sealing a shaft periphery of a rotary shaft inserted in a machine body with a mechanical seal, and fixing the mechanical seal by incorporating it into an inner diameter portion of a seal cover mounted on the machine body. And a rotary side seal part which is provided on the outer circumference of a sleeve liner mounted around the axis of the rotary shaft via a packing and is in sliding contact with the stationary side seal part, and the stationary side seal part side of the seal cover. From the shaft sealing device provided with a quenching hole for injecting and discharging the cooling fluid into the inner peripheral space thereof, the stationary side seal portion side is located at a position corresponding to the inner peripheral side of the packing on the outer peripheral surface of the rotating shaft. A step portion having a small diameter is formed, and a tip portion of the sleeve liner protrudes from an outer periphery of the step portion of the rotary shaft toward an inner peripheral space of the stationary side seal portion, and the tip portion and the small diameter portion of the rotary shaft. Between , Shaft seal and wherein the cooling fluid from the quenching hole has a space portion that can flow.