JPH067222Y2 - mechanical seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a static type / inward flow type mechanical seal used for axially sealing a rotating shaft of a machine body.

[Prior Art] Conventionally, in this type of mechanical seal, as illustrated in FIG. 3, a main ring that is a rotary ring around the rotary shaft (2) inserted into the seal box (1) of the machine body is used. Place the ting ring (3), and attach this mating ring (3)
Collar (5) tightened with set screw (4)
The mating ring (3) with the knock pin (6) protruding from the collar (5).
While fixed by engaging with the seal box (1)
A seal cover (9) fixed to a bolt (8) via an intermediate seal cover (7) is attached to the atmosphere side (A) of the inside, and an inner diameter formed by this seal cover (9) and the intermediate seal cover (7). The coil spring (10) and the biasing force of the coil spring (10) are attached to the retainer (11).
And a compression ring (13) which is transmitted to a seal ring (12) which is a fixed ring via the compression ring (13), and a knock pin (14) protruding from the compression ring (13) is engaged with the retainer (11). In addition, a long drive pin (15) in which the compression ring (13) is bridged along the axial direction of the inner diameter portion formed by the seal cover (9) and the intermediate seal cover (7).
There is a structure in which the seal ring (12) is assembled and integrated in a cartridge type so that the seal ring (12) is pressed and slidably brought into contact with the mating ring (3) by engaging with the mating ring.

And, in such a conventional mechanical seal, a sliding portion between the mating ring (3) and the seal ring (12) from a flushing hole (not shown) facing the seal box (1) of the machine body. Flushing is performed by injecting and extracting the self-liquid into.

[Problems to be Solved by the Invention] However, in the above-described conventional structure, in particular, as the coil spring (10) arranged in the inner diameter portion formed by the seal cover (9) and the intermediate seal cover (7), A long one wound with the same diameter is used, which increases the seal cover installation length in the axial direction, and the working parts of the mechanical seal on the stationary side depend on the mating engagement and are difficult to standardize. Therefore, it cannot be assembled compactly, the whole device inevitably becomes large and the cost becomes high, and the weight also increases, which makes it difficult to handle, and the drive pin that prevents the compression ring from rotating is long and Since the arm is long, it is easily deformed or damaged.

Further, since the leaked liquid is likely to collect in the inner diameter portion of the seal cover, there is a problem that the leaked liquid easily solidifies by entering the coil spring and causes malfunctions.

[Object of the Invention] The present invention has been made under the circumstances described above. The purpose of the present invention is to provide a mechanical seal that has a short mounting length and can be assembled in a compact body. To provide.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention fixes a rotary ring around the axis of a rotary shaft that is inserted into a seal box of an airframe, while maintaining the seal box on the atmosphere side. A case is provided in the inner diameter portion of the seal cover attached to, and a fixed ring elastically biased by a coil spring wound in a conical shape is provided in the case. It is configured such that it is assembled into a compression ring, which is prevented from rotating by a protruding drive pin, through a knock pin so as to be pressed and slidably contact with the rotary ring, and in this case, the coil spring A large diameter drain hole is opened in the case directly below, the compression ring is extended to the atmosphere side, and a water partition is provided on the atmosphere side end surface of the case, It is preferable that a partition wall is formed around the coil spring by the water partition portion and the extension portion of the compression ring.

[Operation] That is, according to the present invention, when the seal ring of the stationary side mechanical seal of the mating ring of the moving side mechanical seal assembled around the rotary shaft in the seal box of the machine body is elastically pressed and slidably contacted. As a coil spring which is an assembly operating part of the stationary side mechanical seal, a conical spring wound in a conical shape is used, and by assembling and integrating with another assembly operating part in the case, The static mechanical seal is compactly assembled, its mounting length is shortened, the use of a retainer like the conventional mechanical seal is not required, and the radial volume of the seal ring is reduced, which results in a large diameter. Eliminating the use of the seal cover on the other side to prevent it from being affected by the mating dimensions of the other device, we have standardized the mechanical seal side. Moreover, it can be mounted on a narrow shaft seal in the radial direction.

In addition, since a large-diameter drain hole is opened in the bottom of the case that is directly below the coil spring, the leaked liquid is quickly discharged to the outside, and by forming a partition wall around the coil spring, The leaked liquid is prevented from coming into contact with the coil spring or drive pin in the case, which prevents it from entering the coil spring and solidifying and sticking to it, thus clogging the stationary mechanical side. Occurrence of malfunction of the seal assembly working component is prevented.

Also, since the operating parts such as the coil spring and compression ring are installed on the stationary side, there is no decrease in operability due to the effect of viscous torque when the leak liquid is a highly viscous liquid. In addition, it is possible to prevent the influence of slurry collision such as erosion and impact, and thereby improve viscosity resistance, slurry resistance and vibration resistance.

[Embodiment] The present invention will be described below with reference to the embodiments shown in FIGS. 1 and 2.

FIG. 1 schematically shows a first embodiment of a mechanical seal according to the present invention, in which (21) is a seal box of an airframe. This machine's seal box (21)
A rotary shaft (22) is inserted therein, and a mating ring (23) is arranged at a portion located inside the seal box (21) around the rotary shaft (22). . The mating ring (23) is a set screw (24) and is provided with a first O 2 on the circumference of the rotary shaft (22).
Collar (2
6), a first knock pin (28) which is fitted and held from the outside in a loosely fitted state via a second O-ring (27) and which is projected to the collar (26) is provided with the mating ring ( The mating ring (23), set screw (24), first O-ring (25), collar (2)
6), the second O-ring (27) and the first knock pin (28) constitute an assembly operating part of the dynamic mechanical seal.

On the other hand, a seal cover (30) is attached to an end surface of the seal box (21) of the machine body on the atmosphere side (A) through a gasket (29) by fastening with a bolt (not shown). ), The case (31) is arranged and fixed in an uneven engagement so as not to be pulled out toward the atmosphere side (A), and the case (31) is located on the seal box (21) side. The end surface is a small diameter mouth portion (31a) through which a seal ring (36) described later is inserted through an O-ring (38), and the atmosphere side (A) is opened to form a step as a large diameter mouth portion (31b). It consists of a formed cylinder.

A coil spring (32) wound in a conical shape is arranged in the case (31), and the coil spring (32) has one end (32a) on the large diameter side on the atmosphere side ( The other end (32b) is supported by the compression ring (34), while being positioned and held by the snap ring (33) in (A). The compression ring (34) corresponds to the case (3).
In order to transmit the biasing force of the coil spring (32) to the seal ring (36), the drive pin (35) protruding from the inner wall of the small diameter mouth portion (31a) of 1) is engaged to prevent rotation. The seal ring (36) is engaged with a second knock pin (37) projecting from the compression ring (34) to prevent rotation, and the case (31) ) Is inserted through a small O-ring (31a) through a third O-ring (38) and is assembled and integrated in a cartridge type so as to press and slide against the mating ring (23). ), Coil spring (32), snap ring (33), compression ring (34), drive pin (35), seal ring (36) and third O-ring (37). Those that make up the assembly working components of the mechanical seal.

Further, in the figure, (40) is a large-diameter drain hole opened at the bottom of the case (31) corresponding to just below the coil spring (32). From this drain hole (40) into the case (31). The leaked liquid that tries to accumulate is quickly discharged to the outside.

Further, FIG. 2 shows a second embodiment according to the present invention, which extends to the end (34a) on the atmosphere side (A) of the compression ring (34) in the above-mentioned first embodiment,
In addition, the water partition (5
0) is provided, and a partition wall is formed around the coil spring (32) by the water partition part (50) and the extension part (34a) of the compression ring (34) so that the leaked liquid prevents the coil spring (32). ).

That is, according to the present invention, the stationary side mechanical seal seal ring (36) is attached to the moving side mechanical seal mating ring (23) assembled around the rotary shaft (22) in the seal box (21) of the airframe. In elastically slidingly contacting with each other, a conical spring wound in a conical shape is used as the coil spring (32) which is an assembly operation part of the static mechanical seal, The end side is locked by the snap ring (33), and is assembled into the case (31) together with other assembly actuating parts so that the stationary side mechanical seal can be assembled compactly and its mounting length And eliminates the use of retainers like traditional mechanical seals to reduce the radial volume of the seal ring (36), which Eliminating the use of diameter of the seal cover (30), so as not affected by Togo dimensions of the counterpart equipment, to allow standardization of the mechanical seal side, moreover,
It can be mounted on a narrow shaft seal portion in the radial direction.

Further, since a large diameter drain hole (40) is opened at the bottom of the case (31), which is directly below the coil spring (32), the leaked liquid can be promptly discharged to the outside through the drain hole (40). In addition, as shown in FIG. 2, a partition wall is formed around the coil spring (32) to prevent leakage of the leaked liquid from the coil spring (32) and the drive pin (35) in the case (31). It is possible to prevent the malfunction of the assembly working parts of the stationary side mechanical seal from occurring by contacting with liquid etc. to prevent it from entering the coil spring (32) and solidifying and fixing so as to prevent clogging. Is what makes it possible.

Further, a drive pin (35) is projectingly provided on the inner wall of the small diameter mouth portion (31a) of the case (31), and the drive pin (3
Since the rotation prevention is provided by engaging 5) with the compression ring (34), the drive pin (35) is shortened and the moment arm of the drive pin (35) can be shortened. .

Further, since the operating parts such as the coil spring (32) and the compression ring (34) are assembled on the stationary side, there is no decrease in operability due to the influence of the viscous torque when the leaked liquid is a highly viscous liquid. In addition, even in the case of slurry liquid, it is possible to prevent the effects of slurry collision such as erosion and impact, and by this,
It is intended to improve viscosity resistance, slurry resistance and vibration resistance.

[Effects of the Invention] As is apparent from the above description, according to the present invention, the mating ring of the moving side mechanical seal assembled to the shaft circumference of the rotary shaft in the seal box of the machine body is fitted with the stationary side mechanical seal. When elastically pressing and slidingly contacting the seal ring, one conical spring wound in a conical shape is used as a coil spring that is an assembly operating component of the stationary side mechanical seal, and a case is used together with other assembly operating components. The static mechanical seal can be assembled compactly and the mounting length can be shortened, which reduces the volume of the seal ring in the radial direction. Therefore, the weight can be reduced and the handling can be simplified, and the mechanical size is not affected by the mating dimensions of the counterpart device. It is possible to standardize the tool side, and moreover, it is possible to mount it on the shaft seal portion that is narrow in the radial direction.

In addition, since a large-diameter drain hole is opened in the bottom of the case that is directly below the coil spring, the leaked liquid can be quickly discharged to the outside, and a partition wall should be formed around the coil spring. This prevents the leaked liquid from coming into contact with the coil spring or drive pin in the case, which causes the static mechanical seal to be installed due to clogging caused by the leaked liquid entering the coil spring. It is possible to reliably prevent malfunction of parts.

In addition, since the operating parts such as the coil spring and compression ring are installed on the stationary side, there is no decrease in operability due to the effect of viscous torque when the leak liquid is a highly viscous liquid. In addition, it is possible to prevent the influence of the slurry collision such as erosion and impact, and thereby, it is possible to improve the viscosity resistance, the slurry resistance and the vibration resistance, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing a first embodiment of a mechanical seal according to the present invention, FIG. 2 is a schematic sectional view showing a second embodiment according to the present invention, and FIG. FIG. 3 is a schematic sectional view of an essential part showing an example of the mechanical seal of FIG. (21) Airframe seal box, (22) rotating shaft, (2
3) rotating ring (mate ring), (28) first knock pin, (30) seal cover, (31) case,
(32) coil spring, (34) compression ring, (34a) extension, (35) drive pin,
(36) Fixed ring (seal ring), (37) second knock pin, (40) drain hole, (50) water partition, (A)
Atmosphere side.

Claims (3)

[Scope of utility model registration request] 1. A rotary ring is fixed to the circumference of a rotary shaft inserted in a seal box of a machine body, and a case is provided in an inner diameter portion of a seal cover attached to the atmosphere side of the seal box. A fixed ring that is elastically biased by a coil spring that is wound in a conical shape is provided on the compression ring that is secured to the compression ring by a drive pin that protrudes in the case, and a knock pin is inserted between the compression ring and the compression ring. Mechanical seal that is integrally assembled so as to be engaged with and brought into sliding contact with the rotary ring. 2. The mechanical seal according to claim 1, wherein a drain hole having a large diameter is opened in a case corresponding to a position directly below the coil spring. 3. A compression ring is extended to the atmosphere side, and a water partition portion is provided on the atmosphere side end surface of the case, and a partition wall is provided around the coil spring by the water partition portion and the extension portion of the compression ring. It formed, The mechanical seal of Claim 1 or 2 characterized by the above-mentioned.