JPS6039581Y2 - Fixed part structure of fixed sealing ring in mechanical seal - Google Patents

Description

[Detailed Description of the Invention] (1) Purpose of the Invention The present invention relates to a fixed part structure of a fixed sealing ring in a mechanical seal such as a submersible pump.

Conventionally, the fixed part of the fixed sealing ring in a mechanical seal is the gap between the outer circumferential surface I'd of the metal fixed sealing ring 1' and the inner circumferential surface 3'c of the ring groove, as shown in FIG. 4A. by interposing an O-ring 6', or as shown in Fig. 4B,
It has a structure in which an L-shaped rubber backing 6'' is adhered from the back end surface 1''b of the fixed sealing ring 1'' to the outer peripheral surface I'd.

However, the one in which an O-ring 6' is interposed as shown in FIG. 4A has the disadvantage that the sealing portion is a line contact and the sealing effect of the gap G is poor.

Further, although it can be applied to metal objects, it is difficult to apply to fired crystals due to molding considerations.

On the other hand, when the L-shaped rubber backing 6'' is attached as shown in Fig. 4B, it becomes a heat insulating layer on the back side of the fixed sealing ring 1'', so the heat dissipation property of the heat generated on the sliding surface is poor, and it does not last for a long time. If used, there is a risk that heat will accumulate and cause seizure on the sliding surface.

The object of the present invention is to eliminate such conventional drawbacks and provide a fixed part structure of a fixed sealing ring that has a perfect sealing effect, excellent heat dissipation, and is highly durable.

(2) Structure of the invention In the fixing part structure of the fixed sealing ring in the mechanical seal according to the invention, the front end surface is a sliding surface that contacts the rotating sealing ring, and the back end surface is a non-sliding surface.The fixing part is made of silicon carbide. The sealing ring is housed in an annular groove recessed in the inner wall of the seal box along the outer periphery of the rotating shaft so that the non-sliding surface faces the bottom of the groove, and the outer circumferential surface of the fixed sealing ring and the inside of the annular groove By press-fitting a buffer backing in which a coating layer made of rubber or soft synthetic resin is formed on the inner and outer circumferential surfaces of the metal core ring into the gap between the inner circumference and the curved surface, the inner circumference of the buffer backing and The contact surface between the fixed sealing ring outer circumferential surface and the contact surface between the buffer backing outer circumferential surface and the ring groove inner circumferential surface are configured to be brought into close contact with each other in surface contact.

To explain the drawings illustrating the embodiment, reference numeral 1 denotes a fixed sealing ring whose front end surface 1a is a sliding surface that contacts the rotary sealing ring 2, and whose back end surface 1b is a non-sliding surface, and is made of silicon carbide. It is being

Reference numeral 3 denotes an annular groove recessed in a fixed body 5 such as the inner wall of a seal box along the outer periphery of the rotating shaft 4, and the groove 3 is an annular groove recessed in a fixed body 5 such as an inner wall of a seal box.
The stationary sealing ring 1 is housed in such a manner that it comes into contact with the groove bottom surface 3b, and a buffer backing 6 (described later) is press-fitted into the gap between the outer circumferential surface 1d of the stationary sealing ring 1 and the ring groove inner circumferential surface 3C.

The buffer backing 6 is made of rubber or soft material on the inner and outer circumferential surfaces of the metal core ring 8, for example, by the same method as described in Utility Model Publication No. 1983-45166, page 1, column 2, 3-1': ff. A coating layer 7 made of baked synthetic resin is formed, and is applied to the outer peripheral surface 1d of the fixed sealing ring and the inner peripheral surface 3c of the ring groove.
By press-fitting into the gap between They are brought into close contact with each other in surface contact.

In order to further strengthen this close contact state, for example, as shown in FIG. Using the backing 6, the outer peripheral surface 1d of the fixed sealing ring 1 is formed into an inclined surface having approximately the same angle as the buffer backing inner peripheral surface 6C, and the ring groove inner peripheral surface 3c has approximately the same angle as the buffer backing outer peripheral surface 6d. Formed on an inclined surface.

Then, as shown in FIG. 3A, after fitting the fixed sealing ring 1 into the annular groove 3, as shown in FIG.
By press-fitting the buffer backing 6 along the outer circumferential surface 1d, a wedge action is generated in the circumferential direction, and the close contact effect between the mating and abutting surfaces can be significantly enhanced.

Reference numeral 9 designates a holding plate for preventing rotation and escape of the buffer backing 6, reference numeral 10 designates a bellows that supports the rotary sealing ring 2 from the back side, reference numeral 11 designates a retainer, and reference numeral 12 designates a pressing spring.

(3) Effects of the invention According to the structure of the invention, the buffer backing 6 in which the metal core ring 8 is wrapped in the coating layer 7 allows surface contact between the outer peripheral surface 1d of the fixed sealing ring 1 and the inner peripheral surface 3c of the ring groove. The adhesion becomes strong and the sealing effect is perfect.

Unlike the conventional structure in which an O-ring is interposed, this structure can also be applied to baked products, and since the fixed sealing ring 1 is made of silicon carbide, it has excellent wear resistance.

Also, unlike the conventional structure in which an L-shaped rubber backing is attached, the back end surface 1b of the fixed sealing ring 1 is the ring bottom surface 3 of the ring groove 3.
Since it is in direct contact with b, the heat dissipation is extremely good, and there is an advantage that seizure does not occur on the sliding surface even if used for a long time.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional side view of the main part of the mechanical seal according to the structure of the invention, A and B in Fig. 2 are half sectional views of the buffer backing in the structure of the invention, and A-C in Fig. 3 are other views of the mechanical seal with the structure of the invention. 4A and 4B are longitudinal sectional side views of essential parts illustrating the fitting procedure in the embodiment, and FIGS. 4A and 4B are longitudinal sectional side views of essential parts illustrating the fixing part structure of a fixed sealing ring in a conventional mechanical seal. 1... Silicon carbide fixed sealing ring, 1a
...Front side end surface, 1b... Back side end surface, 1
d...Outer peripheral surface, 2...Rotating sealing ring, 3
......Ring groove, 3b...Ring groove bottom surface, 3c
......Inner peripheral surface of the ring groove, 4...Rotating shaft, 6.
...Buffer backing, 6c...Inner circumferential surface of loose backing, 6d...Outer circumferential surface of buffer backing, 7...Coating layer, 8...・Metal core ring.

Claims (1)

[Scope of utility model registration request] A fixed sealing ring 1 made of silicon carbide, whose front end surface 1a is a sliding surface that contacts the rotating sealing ring 2 and whose back end surface 1b is a non-sliding surface, is recessed in the inner wall of the seal box along the outer periphery of the rotating shaft 4. The outer peripheral surface 1 of the fixed sealing ring 1 is accommodated in the provided ring groove 3 so that the non-sliding surface faces the groove bottom surface 3b.
A buffer backing 6 on which a coating layer 7 made of a comb or soft synthetic resin is formed by baking a comb or soft synthetic resin on the inner and outer circumferential surfaces of the metal core ring 8 is press-fitted into the gap between the ring groove inner circumferential surface 3c and the inner circumferential surface 3c of the metal core ring 8. By doing so, the contact surface between the buffer backing inner circumferential surface 6c and the fixed sealing ring outer circumferential surface 1d and the buffer backing outer circumferential surface 6c
A fixed part structure of a fixed sealing ring in a mechanical seal configured such that the opposing surfaces of and annular groove inner circumferential surface 3c are brought into close contact with each other in surface contact.