JPH0128385Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to mechanical seals, and in particular to a sliding mechanical seal consisting of a floating seat that rotates with the shaft and a seal ring that is attached to the stationary body. The aim is to provide technology that integrates parts.

[Conventional technology]

Conventionally, for example, in a mechanical seal as shown in FIG. 8, in which a floating seat that rotates with the shaft and a seal ring carried on the housing side slide in pressure contact to seal the shaft, a seal ring 50 is used.
An outer cylinder 52 is inserted and fixed to the end of the housing 51.
They are fitted together with a packing 53 and a spring retainer 54, and are fixed to each other by adhesive or the like, and at the same time are elastically biased by a coil spring 55. Further, a floating sheet 56 that is in sliding contact with the seal ring 50 is press-fitted into the outer end periphery 58a of a sleeve 58 which is inserted and fixed onto the shaft 57 via a buffer rubber 59, and the sleeve 58 is inserted into the outer cylinder 52. After that, the inner end is bent outward to form a caulked edge 60 to integrate all parts, and this mechanical seal is assembled into the shaft seal of the equipment using a special assembly jig. It is something.

[Problem that the invention attempts to solve]

Therefore, in the above configuration, the length of the sleeve 58 becomes long and deep drawing is performed, so a special material is used to prevent aging cracking, and post-processing is required to caulk the sleeve 58 to integrate the rotating side and the stationary side. In addition to requiring a process, it is also necessary to apply a sealant to seal with the shaft 57, which not only increases costs, but also causes problems such as deformation of the sleeve 58 due to the caulking process, resulting in poor dimensional accuracy. had.

The present invention was developed in view of the above problems, and aims to reduce production costs by omitting a sleeve made of a special material that requires dimensional accuracy in a mechanical seal.

[Means for solving problems]

The mechanical seal of the present invention has a floating sheet supported on a rotating side member that is externally fixed to the shaft side, and a seal ring supported on a fixed side member that is fixedly installed on the housing side, and both sliding surfaces apply appropriate pressing force. configuring an axial engagement means between the rotating side member and the stationary side member so as to bring them into close contact with each other;
After the mechanical seal is installed, the engaging means is removed in its assembled state.

That is, the above-mentioned engagement means has a plurality of engagement protrusions extending from the engagement cylinder press-fitted into the outer cylinder of the fixed member to the outer edge of the case of the rotating member, and is formed on the inner surface of the distal end of the engagement protrusions. It has a structure in which the engaging claw engages with the outer edge of the case, and constitutes a mechanical seal before assembly in which a floating sheet airtightly supported on the outer cylinder side is elastically pressed against a seal ring fixed to the case. After installation, the engaging protrusion is bent and removed to release the fixed member and rotating member.

[Effect]

According to the above configuration, the rotating side member and the fixed side member are
Due to the elastic biasing structure, the seal ring is constantly pressed so as to protrude in the axial direction, so when both members are engaged via the engagement means, the engagement protrusion comes into pressure contact with the back surface of the outer edge of the case, causing both members to be unified. After the mechanical seal is interposed between the housing and the shaft, the engaging protrusion is broken and the engaging claw is released from the outer edge of the case. At the same time, the seal ring slides closely against the floating seat, allowing free rotation. exerts its effect.

〔Example〕

Embodiments of the mechanical seal of the present invention will be described below with reference to the drawings. FIGS. 1 to 5 show the first embodiment. Reference numeral 1 denotes a stationary side member fixedly installed on the housing a side, and a seal ring 3 is carried on the end of an outer cylinder 2 in which a flange-like outer wall 2b is inserted and fixed to the end of the shaft hole of the housing a. The seal ring 3 is fitted onto the outer circumferential end of the inner wall 2a of an annular body having a substantially U-shaped cross section, and is attached to an appropriate number of anti-rotation protrusions 4 bulging out evenly on the outer circumference of the inner wall 2a. It is engaged with a rotation stopper notch 5 so as to be slidable in the axial direction. Further, reference numeral 6 is inserted into the inner wall 2a of the outer cylinder 2, and both ends are connected to the bottom wall 2c.
This is a packing formed by closely contacting the rear surface of the seal ring 3 and fixed by adhesive etc., and the packing 6
The coil spring 7 inserted into the seal ring 3 is elastically biased to expand the packing 6 in the axial direction through the spring retainers 8, 8, and presses the seal ring 3 in the direction of arrow A. Reference numeral 9 denotes the outer wall portion 2 of the outer cylinder 2.
b An engagement tube made of hard synthetic resin with a cylindrical base 9a press-fitted into the inner periphery, and a plurality of (three in this embodiment) engagement protrusions 9 protruding from the cylindrical base 9a in parallel with the axis.
An engaging claw 9c is formed inward at the b end, and
A half-cut groove 9 for removing bending is provided at the base end of the engagement protrusion 9b.
d. Reference numeral 10 denotes a rotating member that rotates integrally with the shaft b side, and includes an annular groove 12a of a cushioning rubber 12 fixed to the case 11, which has a substantially U-shaped cross section, by adhesive or baking.
The floating sheet 13 is fitted and integrated into the case 11, and the outer circumferential portion of the case 11 is bent in the outer radial direction to form an outer edge 1 that engages with the engagement claw 9c of the engagement tube 9.
It consists of 4.

The fixed side member 1 and the rotating side member 10 press against the seal ring 3 and the floating seat 13 against the elasticity of the coil spring 7, while slightly pushing the end of the engagement protrusion 9a of the engagement tube 9 in the outer radial direction. While opening, the engaging claws 9c are engaged with the rear surface of the outer edge 14 to integrate them, and the packing 6, coil spring 7, and buffer rubber 12 are integrated by the tightening margins.

As shown in FIG. 1, the mechanical seal having the above structure is constructed by inserting the outer cylinder 2 of the fixed side member 1 onto the shaft a, and then fixing it on the inner surface of the inner cylinder part 11b of the case 11 of the rotating side member 10. The shaft hole 12b of the buffer rubber 12 is inserted airtightly, and the impeller 15 is attached to the shaft, for example, as shown in FIG. The outer wall portion 2b is inserted and fixed in an airtight manner. Therefore, the rotating side member 10 is the fixed side member 1.
The engaging protrusion 9 is held in a pressed position against the
c is spaced apart from the outer edge 14 of the case 11, and the coil spring 7 is compressed, resulting in a structure that applies appropriate surface pressure to the sliding surfaces of the seal ring 3 and the floating seat 13. From this state, the tip of the engagement protrusion 9a of the engagement tube 9 is bent in the direction of arrow B, and the end is removed from the half-cut groove 9d, completing the assembly of the mechanical seal.

That is, in the mechanical seal having the above configuration, the engagement means for integrating the stationary side member 1 and the rotating side member 10 is the engagement claw 9c of the engagement tube 9 press-fitted into the outer tube 2.
engages with the outer edge 14 of the case 11, and after assembly, the engaging protrusion 9b of the engaging tube 9 is bent and removed, making it possible to omit parts that require high precision such as a sleeve. It is.

Next, FIGS. 6 and 7 show other embodiments of the engagement tube 9 in the mechanical seal. The engagement cylinder 9 is molded from hard synthetic resin or the like, and requires a press-fitting allowance when inserting and fixing the cylindrical base 9a into the outer wall 2b of the outer cylinder 2. However, in this embodiment, this press-fitting allowance is required. This shows one way to provide compensation.

That is, the cylindrical shape of the engagement tube 9 is improved by the structure in which the hole snap spring 17 having appropriate elasticity is press-fitted into the circular groove 16 provided around the inner diameter surface of the cylindrical base 9a of the engagement tube 9. An elastic force is applied to the base portion 9a in the outer diameter direction, and together with the material of the engaging tube 9, a press-fitting margin can be provided between the inner diameter of the outer wall portion 2b of the outer tube 2. It is also possible to shorten the length of the shaped base portion 9a.

[Effect of idea]

As mentioned above, the mechanical seal of the present invention eliminates the need for a sleeve that requires high-precision machining, so it eliminates the incidence of aging cracking, improves dimensional accuracy, and exhibits an excellent shaft sealing effect. In addition, since the engagement means between the stationary side member and the rotating side member does not require post-processing such as caulking, problems such as deformation of the sleeve do not occur. is extremely large.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of the first embodiment of the mechanical seal of the present invention when assembled, Fig. 2 is a half-cut sectional view showing the state during operation, and Fig. 3 is a perspective view of the engagement tube. , FIG. 4 is an end view of the same, FIG. 5 is a sectional view taken along the line - in FIG. 4, FIG. 6 is a front sectional view of the second embodiment when assembled, and FIG. The perspective view and FIG. 8 are half-cut sectional views showing a conventional mechanical seal. DESCRIPTION OF SYMBOLS 1... Fixed side member, 2... Outer cylinder, 3... Seal ring, 6... Packing, 7... Coil spring, 9... Engaging tube, 9b... Engaging protrusion, 9c...
...Engagement claw, 10... Rotating side member, 11... Case, 12... Buffer rubber, 13... Floating sheet, 14... Outer edge, 16... Annular groove, 17...
...Snat spring, a...housing, b...shaft.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A floating sheet supported on a rotating side member that is externally fixed to the shaft side, and a seal ring supported on a fixed side member that is fixedly installed on the housing side. An end portion of the engaging means extending from the rotating side member is engaged and integrated with the outer edge of the rotating side member so as to be brought into close contact with an appropriate pressing force, and
A mechanical seal characterized in that the engaging portion of the engaging means can be bent and removed to release both of the members. (2) The engagement means consists of an engagement tube made of synthetic resin that is inserted into the outer tube of the rotating side member with an appropriate tightness, and an engagement projection end protrudes from the cylindrical base of the engagement tube. 2. The mechanical seal according to claim 1, wherein the mechanical seal engages with the outer edge of the case of the rotating member, and the engaging protrusion is bent and removed.