JPH0129313Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention Industrial application field For example, the technical field of mechanical seals used as sealing devices for the bearings of water pumps, which are engine cooling engines of automobiles, and bearing seals combined therewith; This is a similar technical field for waterproof seals.

BACKGROUND ART FIG. 4 shows the structure of a generally used sealing device for a bearing for a water pump.

1 is the water pump shaft, 2 is the bearing seal, 3
4 is an outer ring of the bearing, 4 is a pump housing, 6 is an impeller, 8 is a mechanical seal, and 9 is a drain hole for draining water that has entered from the mechanical seal portion and accumulated in the space 7.

Generally, a mechanical seal is a sealing means used as a waterproof sealing device for the above-mentioned pump, but its waterproofing effect is still not perfect, and water inside the pump chamber may leak from the mechanical seal and enter the space 7. cannot be completely prevented.

On the other hand, although the inside of the bearing is sealed with the bearing seal 2, if water gets inside the bearing,
Bearing life may be shortened. Therefore, a drain hole 9 is formed in the space 7 to sufficiently drain the water that has entered the space 7.Currently, this drain hole 9 is used as a sealing device for a water pump bearing. It has become indispensable.

The problem that the idea aims to solve The above conventional device has the following drawbacks.

1 The water pump shaft 1, bearing seal 2, outer ring 3 and rolling elements are one unit,
All of the above-mentioned parts can be assembled at once by simply assembling this unit into the housing 4, but the mechanical seal 8 needs to be assembled separately into the housing, which requires a large number of assembly steps.

2. The axial positioning of the mechanical seal 8 is done at the fitting part with the housing 4.
The machining accuracy of the housing 4 itself is poor, and the installation position of the mechanical seal tends to vary in the axial direction. As a result, the pressure of the spring of the mechanical seal 8 changes, which adversely affects sealing performance.
It is difficult to obtain stable quality as a water pump.

The above-mentioned drawbacks can be overcome by integrating the mechanical seal and the bearing seal into a single unit that is incorporated into the outer ring. However, when an integrated seal is used, the following new problems arise.

The above-mentioned integrated seal has US Patent No.
No. 3,511,513 is known, but since it uses an integrated seal, the space 7 is eliminated, and it is necessary to devise a position for forming the drain hole.

In the case of the known example, the fitting part of the mechanical seal with the housing is eliminated and water is drained directly from inside the mechanical seal to a drain hole formed in the housing, but water accumulates in the space adjacent to the seal. Water is not drained directly to the drain hole, so the draining effect is insufficient.

Furthermore, because the mechanical seal part is not fitted into the inner circumference of the housing and is positioned within the housing only at the fitting part with the bearing outer ring formed on the outer circumference of the bearing seal, it is not firmly fixed within the housing. . Therefore, the mechanical seal itself tends to wobble in the radial and axial directions, and the sealing performance also deteriorates.

Also, since the mechanical seal and the housing are sealed with an O-ring, the force exerted by the spring of the mechanical seal against the sliding surface is reduced by this O-ring.
This is suppressed by the ring, making it necessary to increase the pressing force itself. Therefore, the frictional force on the sliding surface of the mechanical seal increases, causing wear on the sliding surface and increasing rotational torque.

Means for solving the structural problems of the invention In the present invention, in a seal unit in which a mechanical seal and a bearing seal are combined,
One end of the elastic mantle of the outer cylinder of the mechanical seal and the outer peripheral surface of the bearing seal are intended to fit into the outer ring of the bearing, and the other end of the outer cylinder mantle of the mechanical seal is intended to fit tightly into the housing, and the mechanical seal The outer sleeve of the mechanical seal and the elastic body of the bearing seal are joined at their mutual end faces, and the end face of the outer sleeve of the mechanical seal and the outer peripheral surface extending between the bearing outer ring and the housing are radially, axially, and radially arranged. A means for solving the above-mentioned problems is a waterproof seal unit in which a directional and annular water passage is formed and the annular passage is located in a drain hole of a housing.

Further, in the present invention, the outer circumferential portion of the outer cylinder sleeve of the mechanical seal is formed in a stepped shape consisting of three outer circumferential surface portions having different outer diameters and two radial plane portions communicating the outer circumferential surface portions, The outer circumferential surface portion with the smallest outer diameter and the outer circumferential surface of the bearing seal are intended to fit closely into the bearing outer ring, and the one radial flat portion communicating with the outer circumferential surface portion is the outermost surface of the bearing outer ring. The outer circumferential surface portion having a large diameter is brought into close contact with the housing, and the intermediate outer circumferential surface portion, the other radial plane portion, the housing, and the outer ring end surface form a space continuous in the circumferential direction, and the space portion and A plurality of water passages are formed in a radial manner at the joint portion of the mechanical seal and the bearing seal to communicate with the water drain hole, and the other water passages that are continuous with the water passages are connected to the outer cylinder of the mechanical seal. The problem was solved by the above-mentioned waterproof seal unit formed by grooves formed in the outer circumferential surface portion of the sleeve with the smallest diameter and the radial plane portion communicating with the outer circumferential surface portion.

Effect Since the present invention has the above-mentioned configuration,
The mechanical seal can be integrated with the bearing by incorporating it into the bearing together with the bearing seal, and even if water intrudes into the mechanical seal, it will flow from the space between the bearing seal and the mechanical seal to the water drain hole in the housing via the water passage. It can be discharged directly from

Embodiment In FIGS. 1 to 3, the mechanical seal 11 includes an inner cylinder 41 with a channel-shaped cross section fitted onto the shaft 10, and a buffer ring 2 disposed within the channel of the inner cylinder 41.
a seat ring 1 held on its inner periphery via;
A driven ring 3 is provided with an annular convex portion 3' in contact with the end surface of the seat ring 1 and receives thrust from a bellows 4 and a spring 6, which will be described later. It consists of an outer cylinder 5 forming a spring housing space around the sleeve portion, an elastic jacket C made of rubber or the like bonded to the outer surface of the flange 5'' of the outer cylinder and the outer periphery of the outer cylinder 5. One end of the bellows 4 is fitted into the driven ring 3, and the other end is in contact with the flange 5'' of the outer cylinder 5.The spring 6 is installed between the spring seat 7 on the driven ring 3 and the flange at the other end of the bellows 4. is included.

The outer circumference of the elastic sleeve C is formed into a step-like shape by outer peripheral surface portions 14, 15, 16 having different outer diameters, and radial plane portions 17, 18 connecting these.

Here, 9 is a housing having an inner periphery to be sealed, and 8 is an outer ring of a bearing B fitted into the shaft hole.

The outer periphery 16 of the mantle C of the mechanical seal 11 having the largest outer diameter is closely fitted to the inner periphery of the housing 9, and for the outer ring 8 of the bearing, the outer periphery 16 of the outer ring C has the largest outer diameter. Small outer peripheral surface portion 14
are designed to fit together.

Next, a plurality of protrusions 12 are formed on the end surface of the sleeve C. Further, the bearing seal 31 for sealing grease for the bearing B has a donut-shaped core 32 whose outer periphery is covered with a thick joining elastic body 33, and has a lip 34 with a bifurcated cross section on its inner periphery. There is. A recess 13 corresponding to the plurality of protrusions 12 of the mechanical seal is formed on one end surface of the elastic body 33.
It is provided continuously around the circumference of 3.

By tightly connecting the protrusion 12 to any circumference of the recess 13 of the bearing seal 31, the mechanical seal 11 and the bearing seal 31 are joined to form a unit.

Of course, the outer diameter of the bearing seal 31 and the outer circumferential surface portion 14 of the mechanical seal 11 have the same diameter, and are integrally fitted into the enlarged diameter portion of the outer ring 8.

Six grooves 20 are formed in the radial direction on the end surface of the elastic sleeve C of the mechanical seal 11 on the side of the bearing seal 31, and grooves 21 are formed in the outer circumferential surface 14 in the axial direction communicating with the grooves. Also formed in the radial plane 17 is a groove 22 that communicates with the grooves 20 and 21 and opens to the outer circumferential surface portion 15.

The outer circumferential surface portion 15 is connected to the housing 9 between the radial flat portion 18, the housing 9, and the end surface of the bearing outer ring 8.
An annular passage 23 is formed along the inner peripheral surface of the housing, and the space 23 communicates with a drain hole 24 of the housing.

Effects According to the present invention, it is easy to join the mechanical seal and the bearing seal, and since the mechanical seal and the bearing seal are integrated with the bearing, it is possible to reduce the number of man-hours required to incorporate the device into the housing. At the same time, since both a part of the mechanical seal and the bearing seal are fitted and fixed to the outer ring, the positioning accuracy of the seal is improved, wobbling of the seal can be completely prevented, and sealing performance can be improved.

Furthermore, the water that has entered the mechanical seal is drained from the space 25 between the mechanical seal and the aforementioned grooves 20 and 2.
1, 22, and 23 directly to the drain 24, the drainage effect is significantly improved.

Moreover, since there is no member that obstructs the axial movement of the mechanical seal by the spring, the contact pressure on the sliding surface of the mechanical seal can be set to the optimum condition, preventing rapid wear of the sliding surface and increased contact pressure. An increase in rotational torque can be prevented.

In the case of this embodiment, the passageway provided at the joint between the mechanical seal and the bearing seal is designed to allow both seals to be attached and removed, and to be formed on at least one of their opposing surfaces (on the mechanical seal side in this embodiment). Therefore, processing of the water passage becomes extremely easy.

In addition, since the water passage itself is formed by a plurality of grooves formed in the radial direction and the annular passage 23, there is no need to align the water passage and the water drain, and they can be assembled without considering their direction. Seal assembly man-hours can be further reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of the article of the present invention shown in a state of use, FIG.
A side view taken along the - line in the figure, and FIG. 4 is a longitudinal sectional view of the conventional device. 11... Mechanical seal, 31... Bearing seal, 5... Outer cylinder, C... Elastic sleeve, 8... Bearing outer ring, 9... Housing, 33... Elastic body part, 1
4, 15, 16... Outer peripheral surface portion, 20... Radial groove, 22... Radial groove, 21... Axial groove, 2
3...Annular groove, 25...Space, 24...Drain hole, 12...Protrusion, 13...Recess.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a seal unit in which a mechanical seal and a bearing seal are combined, one end of the elastic sleeve of the outer cylinder of the mechanical seal and the outer peripheral surface of the bearing seal fit into the outer ring of the bearing. the other end of the elastic sleeve of the outer cylinder of the mechanical seal is tightly fitted into the housing, the sleeve of the mechanical seal and the elastic body of the bearing seal are joined at their mutual end surfaces, A waterproof seal in which radial, axial, radial, and annular water passages are formed on the end face of the sleeve and on the outer peripheral surface spanning the bearing outer ring and the housing, respectively, and the annular passages are located in the water drain hole of the housing. Unit (2) The outer periphery of the outer cylindrical sleeve of the mechanical seal is formed into a stepped shape consisting of three outer circumferential surface portions having mutually different outer diameters and two radial plane portions connecting the outer circumferential surface portions, The outer circumferential surface portion having the smallest outer diameter and the outer circumferential surface of the bearing seal are intended to fit closely into the outer ring, and the one radial flat portion communicating with the outer circumferential surface portion is brought into contact with the end surface of the bearing outer ring. Preferably, the outer circumferential surface portion with the largest outer diameter is brought into close contact with the housing, and a space portion continuous in the circumferential direction is formed between the intermediate outer circumferential surface portion, the other radial plane portion, the housing, and the outer ring end surface. , the space portion and the water drain hole are communicated with each other, and a plurality of water passages are formed in a radial manner at the joint portion of the mechanical seal and the bearing seal, and the other water passages are connected to the water passages. The waterproof type according to claim 1, wherein the water channel is formed by a groove formed in the smallest diameter outer circumferential surface portion of the outer cylindrical sleeve of the mechanical seal and a radial plane portion communicating with the outer circumferential surface portion. Seal unit (3) enables the joint portion of the mechanical seal and the bearing seal to be attached and detached, and forms a plurality of radial grooves in at least one of the joint portions of both seals, and when the two seals are joined, A waterproof seal unit (4) according to claim 2 of the registered utility model, in which the groove portion serves as a water passage. The waterproof seal unit (5) according to claim 3, wherein a circumferentially continuous groove is formed at an end opposite to the protrusion to fit into the protrusion and join both seals. is formed on the end face of the mechanical seal, and the groove is formed on the bearing seal.