JPH0614156Y2 - Torque transmission device for mechanical seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a torque transmission device of a mechanical seal applied to a shaft sealing portion of a shaft sealing mechanism.

(Prior Art) A torque transmission device of a mechanical seal applied to a shaft-sealing portion of a shaft-sealed device is conventionally known as shown in FIG.

That is, a key groove b is formed in the inner peripheral portion of a rotary seal ring B to which a metal reinforcing ring A is fitted and fixed by, for example, shrink fitting, and the key groove b and the key groove d formed in the rotary shaft D are formed. A key E is interposed between them, and metal annular spacers F1 and F2 are arranged on both sides of the rotary seal ring B in the axial direction.
The rotary seal ring B is sandwiched via 1 and F2, and an O-ring G is provided to secure the seal between the rotary seal ring B and the spacers F1 and F2. Therefore, the torque of the rotary shaft D is transmitted to the rotary seal ring B via the key E, and the seal end surface of the rotary seal ring B and the seal end surface of the stationary seal ring H are hermetically sealed.

Further, a torque transmission device shown in FIG. 6 is known. This torque transmission device holds a rotary seal ring B by a pair of spacers F1 and F2, which are attached to the rotary shaft D so as to be simultaneously rotatable with the rotary seal ring B and the spacer F.
An O-ring G is provided to ensure a tight seal between 1 and F2. Therefore, the torque of the rotating shaft D is once transmitted to the spacers F1 and F2, and due to the frictional force generated from here between the spacers F1 and F2 and the sandwiched surface of the rotating seal ring B, the rotating seal ring B is rotated.
The rotary sealing ring B and the stationary sealing ring H are sealed and axially sealed.

(Problems to be Solved by the Invention) In the torque transmission device shown in FIG. 5, since the key E is used as the torque transmission mechanism, a large torque can be transmitted, so that even a mechanical seal for high load can be transmitted. It can be said that this is an applicable mechanism.

However, since the rotary seal ring B is generally formed of an ultra-hard brittle material such as ceramics, tungsten carbide, and silicon carbide, forming the key groove b on the rotary seal ring B is troublesome. That is, since the rotary seal ring B made of the above-mentioned super-hard brittle material is molded by sintering, it is necessary to perform processing for forming the key groove b on the molding die, which deteriorates the workability of the die. . Moreover, the space corresponding to the key groove b is the rotary seal ring B.
In addition to reducing the strength of the rotary seal ring B,
Since stress concentrates on the corners of the key groove b, if a large load is shocked upon the rotation start of the rotary shaft D and the key groove b is shocked, cracks or breaks will occur from the stress concentrated portion, and the stress will be deteriorated over time. It becomes a factor that destroys the rotary seal ring B.

On the other hand, in the torque transmission device shown in FIG.
Since the torque is transmitted by the frictional force generated between 1, F2 and the rotary seal ring B, the rotary seal ring B is cracked or broken like the device shown in FIG. Although there is no danger of destroying B, torque transmission is performed only by the above-mentioned frictional force, so if the attachment force of the rotary seal ring B by the spacers F1, F2 is insufficient,
Relative rotation occurs between the two F1 and F2, and torque cannot be properly transmitted. Further, if the clinging force becomes excessive, surface distortion will occur in the rotary seal ring B and the sealing force will be significantly reduced, and no matter how great the clinging force is, relative rotation can be reliably prevented. No, it has the disadvantage that a large torque cannot be transmitted.

The present invention has been made in view of such circumstances, and enables transmission of a large torque, avoids a problem that cracks and breaks occur in the rotary seal ring, and simplifies the rotary seal ring molding die. It is an object of the present invention to provide a mechanical seal torque transmission device capable of improving the workability of a mold.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a rotary side sealing element provided with a rotary sealing ring made of a hard brittle material that rotates simultaneously with a rotary member of a shaft-sealed device, A mechanical seal having a stationary side sealing element provided with a stationary sealing ring fixed to the casing side of a shaft sealing device, wherein a sealing end face of a rotary sealing ring and a stationary sealing ring are slidably contacted to form a shaft sealing portion. A metal reinforcing ring is externally fitted and fixed on the outer periphery of the rotary seal ring, and a metal annular retainer is attached to the rotating member via a torque transmission mechanism so as to be rotatable at the same time, and the reinforcing ring and the annular retainer are engaged with each other. They are configured to be engaged with each other via a mechanism and to transmit torque from the annular retainer to the rotary seal ring via the reinforcing ring.

(Operation) According to the present invention, torque transmission from the rotary member to the rotary sealing ring made of a hard and brittle material is interposed between the rotary member and the annular retainer made of metal, and the annular retainer made of metal. And a metal reinforcing ring that is externally fitted and fixed to the outer circumference of the rotary seal ring, and the rotary seal ring made of hard brittle material is not directly subjected to a large impact load locally. The rotating seal ring made of brittle material is effectively prevented from cracking or breaking.

Further, by the cooperation of the torque transmission mechanism and the engagement mechanism, a large torque can be transmitted to the rotary seal ring, and further, the processing for assembling the torque transmission mechanism and the engagement mechanism to the rotary seal ring can be omitted, The rotary seal ring molding die is simplified accordingly.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a half cross-sectional view showing an embodiment of the present invention, in which a mechanical seal 1 and a rotary side sealing element 10 that rotates simultaneously with a rotary member (rotary shaft in this embodiment) 2 of various shaft-sealed devices. It has a fixed-side sealing element 20 fixed to the casing 3 of the shaft-sealed device.

The rotary side sealing element 10 includes a rotary seal ring 11 and a reinforcing ring 1.
The stationary-side sealing element includes a stationary sealing ring 21 formed of, for example, a carbon-based material, a stationary ring 22 formed of a rusted metal such as stainless steel, and an annular retainer 23. And the annular retainer 23 is non-rotatably and liquid-tightly fitted and held in the casing 3, and the annular retainer and the stationary ring 22 are provided in plural at equal intervals in the circumferential direction (not shown). ) To hold the stationary ring 22 in a non-rotatable manner and a plurality of stationary rings 22 and stationary sealing rings 21 are provided at equal intervals in the circumferential direction. (Only the locking pin is shown) to hold the stationary sealing ring 21 non-rotatable. Further, an O-ring 5 made of an elastic body is provided between the annular retainer 23 and the stationary ring 22 and between the stationary ring 22 and the stationary sealing ring 21, respectively.
Is interposed and sealed, and the spring 6 is interposed between the annular retainer 23 and the stationary ring 22 by being compressed in the axial direction. Therefore, the spring force of the spring 6 urges the stationary seal ring 21 toward the rotary seal ring 11 side to seal the respective seal end faces to form the shaft seal portion 30.

The rotary seal ring 11 is formed of, for example, an ultra-hard brittle material such as silicon carbide, and a reinforcing ring 12 made of rusted metal such as stainless steel is externally fitted and fixed to the outer periphery by, for example, shrink fitting, and the center The rotary member 2 is inserted into the hole 11A, and one axial end of the central hole 11A is in contact with the step surface 2A of the rotary member 2.

The annular retainer 13 is made of rusted metal such as stainless steel, and has a disk portion 13A, a locking piece 13B, one end side boss portion 13C, and the other end side boss portion 13D. As shown in FIG. 2, a plurality of locking pieces 13B are arranged at equal intervals in the circumferential direction on the outer peripheral portion of the disk portion 13A toward the one end side in the axial direction (the reinforcing ring 12 side in FIG. 1). (For example, four) are formed to extend. Further, as shown in FIGS. 1, 3, and 4, a plurality of locking pieces 13B are formed on the outer circumference of the reinforcing ring 12 by forming locking grooves 12A with which the locking pieces 13B are respectively engaged. The engaging mechanism 7 is formed by engaging the engaging groove 12A with the engaging groove 7.

The key groove 13 is formed on the inner peripheral surface of the other end side boss portion 13D of the annular retainer 23 and the outer peripheral surface of the rotating member 2, respectively.
d and 2B are formed, and the key grooves 13d and 2B and the key 8A constitute the torque transmission mechanism 8. That is, the annular retainer 13 is attached to the rotating member 2 via the torque transmission mechanism 8 so as to be simultaneously rotatable. Further, a nut 9 is screwed into the male screw portion 2a of the rotating member 2, and the other end surface (rear end surface) of the other end side boss portion 13D of the annular retainer 13 is pressed by the tip of the nut 9 to rotate through the one end side boss portion 13C. The sealing ring 11 is pressed against the step surface 2A of the rotating member 2. Then, between the rotary seal ring 11 and the rotary member 2 and the rotary seal ring 1
An O-ring 31 made of an elastic material is provided between 1 and the boss portion 13C on one end side of the annular retainer 13 for sealing. Reference numeral 32 in the figure denotes a circulating hole for the sealing liquid.

In the above configuration, the rotary member 2 to the rotary side sealing element 1
Torque transmission from the rotary member 2 to the torque transmission mechanism 8
Is transmitted to the ring-shaped retainer 13 via the ring retainer 13 and the ring-shaped retainer 13 is transmitted from the ring-shaped retainer 13 via the engagement mechanism 7 to the rotary seal ring 11 externally fitted and fixed by shrink fitting. Done by

Since the torque transmission mechanism 8 is composed of the key grooves 2B and 13d and the key 8A, a large torque can be transmitted.
Moreover, since the keyways 2B and 13D are formed in the rotating member 2 and the annular retainer 13 which are made of a material having high toughness, a large load is applied to the torque transmitting mechanism 8 due to the rotational starting force of the rotating member 2. Keyway 2B, 13d
Even if a large stress concentration occurs in the corners of the above, the torque transmission mechanism 8 will not be damaged due to cracks or breaks from this stress concentration portion.

Further, since the engagement mechanism 7 is composed of the plurality of locking grooves 12A formed in the reinforcing ring 12 and the locking pieces 13B of the annular retainer 13 which are respectively locked in the locking grooves 12A, the torque transmission mechanism. Similar to item 8, it has a function of transmitting a large torque. And the locking groove 12A
And the locking piece 13B are both formed on the reinforcing ring 12 and the annular retainer 13 made of a material having high toughness, and the load can be dispersed and received by the plurality of locking grooves 12A and the locking piece 13B. As a result, a large load is impacted on the engagement mechanism 7 via the annular retainer 13 when the rotary member 2 starts to rotate, and a large stress concentration occurs at the corners of the locking groove 12A and the root of the locking piece 13B. Even if occurs, the engaging mechanism 7 will not be damaged by cracks or breaks from these stress concentration portions.

That is, according to the present invention, by providing the engagement mechanism 7 and the torque transmission mechanism 8, the torque is transmitted while avoiding stress concentration on the rotary seal ring 11 made of the super-hard brittle material. Therefore, the rotary seal ring 11 is not cracked or broken.

In the embodiment described above, the rotary shaft is used as the rotary member 2, but a sleeve that rotates simultaneously with the rotary shaft is externally fitted,
The sleeve may be a rotating member, and the rotary seal ring 11 and the annular retainer 13 may be externally fitted. In addition, the annular retainer 13 includes a plurality of locking pieces 1 from the disk portion 13A.
Although the description is made with the configuration in which 3B is bent, a plurality of locking pieces 13B may be attached to the disk portion 13A by welding.

(Effects of the Invention) As described above, according to the present invention, torque transmission from the rotating member to the rotary sealing ring made of a hard and brittle material is achieved by the torque transmission provided between the rotating member and the metal annular retainer. The rotary seal ring formed by a hard and brittle material is formed by a mechanism and an engagement mechanism between a metal annular retainer and a metal reinforcing ring fitted and fixed to the outer periphery of the rotary seal ring. Large load at startup is not locally applied. Therefore, unlike the conventional case, it is not necessary to form a key groove in the rotary seal ring, so that the deterioration of the strength of the rotary seal ring can be suppressed, and the rotary seal ring is cracked or broken, which causes the rotary seal to rotate over time. It is possible to avoid the inconvenience that the ring is destroyed.

Further, since the torque transmission is performed by the cooperation of the torque transmission mechanism and the engagement mechanism, a large torque can be transmitted, so that it can be applied to a mechanical seal for high load and can be applied to a rotary seal ring. Since the groove processing for assembling the torque transmission mechanism and the engagement mechanism can be omitted, the rotary seal ring molding die is simplified and the workability is improved.

[Brief description of drawings]

1 is a half sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view of an annular retainer, FIG. 3 is a plan view showing a part of an engaging mechanism, FIG. 4 is a front view of the same, and FIG. FIG. 6 is a half sectional view showing an example of a conventional device, and FIG. 6 is a half sectional view showing another example of a conventional device. DESCRIPTION OF SYMBOLS 1 ... Mechanical seal 2 ... Rotating member (rotating shaft) 3 ... Casing 7 ... Locking mechanism 8 ... Torque transmission mechanism 10 ... Rotating side sealing element 11 ... Rotating sealing ring 12 ... Reinforcement ring 13 ... Annular retainer 20 ... Rotating side sealing element 21 ... Stationary sealing ring 30 ... Shaft sealing part

Claims (1)

[Scope of utility model registration request] 1. A rotary-side sealing element provided with a rotary sealing ring made of a hard and brittle material, which rotates simultaneously with a rotary member of an equipment to be sealed.
In a mechanical seal having a stationary side sealing element provided with a stationary sealing ring fixed to the casing side of a device to be shaft-sealed, and slidingly contacting the sealing end faces of the rotary sealing ring and the stationary sealing ring to form a shaft sealing portion, A metal reinforcing ring is externally fitted and fixed to the outer periphery of the rotary seal ring, a metal annular retainer is attached to the rotating member via a torque transmission mechanism so as to be rotatable at the same time, and the reinforcing ring and the annular retainer are engaged. A torque transmission device for a mechanical seal, characterized in that the torque is transmitted from an annular retainer to a rotary seal ring via a reinforcing ring by engaging with each other via a coupling mechanism.