JPH0650695Y2 - mechanical seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement in the structure of a mechanical seal that seals a rotating shaft portion of, for example, a hot water circulation pump or a domestic well water pump.

[Prior Art] Conventionally, in a mechanical seal used in a hot water circulation pump of this type, as shown in FIG. 3, a rotary shaft (3) inserted into a housing (2) of a machine body (1).
When shaft-sealing, the mating ring (4), which is a fixed ring, is press-fitted into the fitting concave ring portion (21) formed on the housing (2) side through a cup gasket (5) having an L-shaped cross section. While inserting and fixing, a seal ring (7), which is a rotary ring, is arranged on the impeller (6) mounted and fixed on the rotary shaft (3) side, and the outer peripheral portion of the seal ring (7) is packed (8). Bake and hold the sliding surface of the mating ring (4) in sliding contact with the sliding surface of the mating ring (4), and further, the outer periphery of the end of the packing (8) by a garter spring (9). ) Is attached to the shaft circumference and the seal ring (7) is attached to the coil spring (1
There is a structure in which the shaft is sealed by elastically pressing and urging in the axial direction toward the mating ring (4) side by the urging force of (0).

However, in the mechanical seal having the above-mentioned conventional structure, as shown in FIG. 4, the cup gasket (5) for inserting and fixing the mating ring (4) into the fitting concave ring portion (21) of the housing (2) is used. Since the outer peripheral surface (5a) of (1) is a flat surface, the insertion force when inserting the mating ring (4) into the fitting concave ring portion (21) of the housing (2) is large, Not only is the attachment work cumbersome, but the sealing properties are poor.

Therefore, in order to make up for the drawbacks of such a conventional structure,
As shown in FIG. 6 and FIG. 6, a bead portion (51) is formed on the outer peripheral surface (5a) of the cup gasket (5) so as to project in the circumferential direction. And a sealing margin is provided between the sealing portion on the fitting concave ring portion (21) side of the housing (2) and the sealing surface on the mating ring (4) side so as to enhance the sealing performance in the press-fitted fitting state. Is the current situation.

[Problems to be solved by the invention] However, in the case where the bead portion (51) is formed so as to project in the circumferential direction on the outer peripheral surface (5a) of the cup gasket (5), the housing (2) There was a problem that the slip force between the fitting concave ring portion (21) and the mating ring (4) was reduced, and the mounting state of the mating ring (4) became unstable.

[Object of the Invention] The present invention has been made under the above circumstances. The purpose of the present invention is to make it easy to assemble the mating ring and maintain a stable mounting state. The purpose is to provide the mechanical seal.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a mating ring through a cup gasket having an L-shaped cross section in a fitting concave ring portion of a machine housing through which a rotary shaft is inserted. A mechanical seal that is inserted and fixed, and a sealing ring that is fixed to the rotating shaft side is elastically slidably contacted with the mating ring to seal the shaft. The plurality of bead portions and the plurality of rib portions extending so as to connect the bead portions in the axial direction are integrally formed to project.

[Operation] The plurality of bead portions which are continuous in the circumferential direction are brought into pressure contact with the fitting concave ring portion of the housing to improve the sealing property of the cup gasket. The ribs that extend in the axial direction between these bead parts have a reinforcing function to prevent deformation such as twisting of the bead part when press-fitting the cup gasket into the fitting concave ring part, and a mating ring during use. Has a slip preventing function of preventing the cup gasket from slipping in the circumferential direction with respect to the fitting concave ring portion by the sliding torque acting on the sliding surface. Further, since the plurality of concave portions defined by the bead portions and the rib portions function like suction cups, a stable mounting state is maintained.

[Embodiment] The present invention will be described below with reference to an embodiment shown in FIGS. 1 and 2. In the illustrated embodiment according to the present invention, the parts having the same structures as those of the mechanical seal and the cup gasket of the conventional structure shown in FIGS. 3 to 6 are designated by the same reference numerals, and the description thereof will be omitted.

In the mechanical seal of this embodiment, two bead portions (51) (51) are formed on the outer peripheral surface (5a) of the cup gasket (5) in a juxtaposed manner along the circumferential direction, and the bead portion (51) is formed. A rib portion (52) extending axially between (51)
... are formed so as to integrally project from each other at a predetermined distance in the circumferential direction. Therefore, the bead portions (51) (51) are reinforced by the rib portions (52), so that the fitting concave ring portion (2) of the housing (2) shown in FIG.
Deformation such as twisting of the bead portions (51) (51) when the cup gasket (5) is press-fitted into 1) is prevented. Further, the plurality of recesses (53) defined by the bead portions (51) (51) and the rib portions (52) are sucker-like with respect to the inner peripheral surface of the fitting recessed ring portion (21). It functions and maintains a stable mounting state by its suction force.

[Effects of the Invention] As is apparent from the above description, according to the present invention, the mating ring is inserted and fixed to the fitting concave ring portion of the machine body housing through which the rotary shaft is inserted through the cup gasket having an L-shaped cross section. Then, in this mechanical seal in which a seal ring fixed to the rotating shaft side is elastically slidably contacted to the mating ring to seal the shaft, a plurality of circumferentially continuous mechanical seals are formed on the outer peripheral surface of the cup gasket. Since the bead portion and the plurality of rib portions extending so as to connect the bead portions in the axial direction are integrally formed to project, the work of assembling the cup gasket holding the mating ring is performed. It is possible to increase the slip force in the circumferential direction with the fitting concave ring part of the machine body housing by forming the rib part protruding. Therefore, an excellent effect that the attachment state of the mating ring can be stabilized by the suction force of the plurality of defined recesses is exerted.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view showing an embodiment of a cup gasket used in a mechanical seal according to the present invention, FIG. 2 is a side view of the same, and FIG. 3 is a conventional mechanical seal mounted on a machine body. FIG. 4 is a schematic main part sectional view showing a state, FIG. 4 is a schematic main part enlarged sectional view of a conventional cup gasket, and FIG. 5 is a schematic main part enlarged sectional view showing another example of a conventional cup gasket. FIG. 6 is a side view of the conventional cup gasket shown in FIG. (1) ... Airframe, (2) ... Housing, (21) ... Mating concave ring, (3) ... Rotating shaft, (4) ... Mating ring, (5) ... Cup gasket, (5a) …… Outer peripheral surface, (51) …… Bead portion, (52) …… Rib portion, (7) …… Seal ring, (10) …… Coil spring.

Claims (1)

[Scope of utility model registration request] 1. A mating ring is inserted and fixed through a cup gasket having an L-shaped cross section in a fitting concave ring portion of a body housing through which the rotary shaft is inserted, and the mating ring is fixed to the rotary shaft side. A mechanical seal in which a seal ring is elastically slidably contacted to seal the shaft, and a plurality of circumferentially continuous bead portions are connected to the outer peripheral surface of the cup gasket in the axial direction. The mechanical seal is characterized in that a plurality of ribs extending in such a manner are integrally formed to project.