JPH10220593A - Sealing device for water pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the squeak of a sliding part by forming second and third sealing members, brought into sliding contact with the surface of a water pump shaft, of polytetrafluoroethylene, forming first and second rigid members, fitted into the core metal inner diameter side of the sealing member, of metal, and mounting the end part of the second rigid member to an outer ring of a bearing. SOLUTION: A water pump shaft rotatory-driven by a drive source is supported to a housing through a water pump bearing 3, and a water pump sealing device 6 is arranged between the bearing 3 and a water pump chamber. This sealing device 6 is composed of a first sealing member 7 formed of L- shaped core metal 7a and rubber material 7b, a second sealing member 8 made of polytetrafluoroethylene resin (PTFE resin) and brought into close contact with the surface of the shaft 1, a first rigid member 9 of channel cross section pressed into the inner peripheral surface of the core metal 7a of the first sealing member 7, a third sealing member 10 made of PTFE resin and brought into close contact with the surface of the shaft 1, and a second rigid member 11 for clamping the third sealing member 10 together with the first rigid member 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water pump sealing device for an automobile, and more particularly, to a water pump sealing device which is excellent in waterproof effect, has a long service life and is easy to assemble.

[0002]

2. Description of the Related Art A water pump for cooling an engine of an automobile is configured such that an impeller mounted on an end of a shaft of a water pump is rotated in a water pump chamber and cooling water is circulated in a water jacket of the engine. It has become. In such a water pump bearing device, since the bearing portion and the water pump chamber are adjacent to each other, water enters the bearing portion side by the sealing device, and the water flows to the outside through the bearing seal portion and the like. Leakage should be almost completely prevented. As a conventional water pump sealing device, for example, as shown in FIG.
A water pump sealing device 26 provided in a space 21 between a bearing seal 20 for sealing the inside of a water pump bearing 3 for supporting the water pump shaft 1 and a water pump chamber 4 filled with cooling water. Are known. This sealing device 26
Is a seal case 22 fitted and fixed to the inner end of the housing 2, and the elastic member 2 held by the seal case 22.
A seal member 23 to which the impeller 5a is fixed, and a sealing ring 24 provided at an end of the impeller boss portion 5b to which the impeller 5a is attached.
And a spring 25 arranged around the elastic member 23a to urge the seal member 23 into contact with the side surface of the sealing ring 24.
And a mechanical seal composed of: When the impeller 5a rotates, the end face of the seal member 23 is in close contact with the side surface of the sealing ring 24 to prevent water from leaking to the water pump bearing 3 side.

[0003]

The mechanical seal of the sealing device constructed as described above can be completely sealed under the conditions of a cooling water temperature of 100 ° C., an internal water pressure of 2 kgf / cm ² , and a rotation speed of 10,000 rpm. It is made to become. However, troubles such as breakage of the water pump bearing due to water leakage from the sliding portion in the sealing device of the water pump or generation of so-called squeal noise in the sliding portion due to poor lubrication have been a long-standing problem of mechanical seals. It is. As one of the causes of water leakage from the sliding portion of the conventional mechanical seal, as described above, the sealing material (the seal member 23) of the mechanical seal contains carbon (or ceramic). Since the sliding member is a hard member, the presence of hard foreign matter in the cooling water may damage the sliding surface. In recent years, lip-type seals have also been developed as mechanical seal alternatives, but in any case, if foreign matter is present in the cooling water,
Abnormal wear occurs due to the foreign matter being caught, leading to early leakage. Another problem is that the sealing device of the water pump has a relatively complicated structure and a large number of parts, so that the assembling operation is complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problem, and it is possible to prevent the generation of squeal noise from a sliding portion and to prevent water leakage for a long time even if foreign matter is present in cooling water. Easy and reliable assembling work
It is intended to provide a sealing device for a tap pump.

[0005]

That is, in order to solve the above-mentioned problems, the present invention provides a water pump sealing device according to the present invention, which comprises a first shell formed by fixing a rubber material around a cored bar. When the first seal member is fitted into the inner diameter side of the core metal of the first seal member and is fitted to the water pump shaft, the inner diameter side is elastically deformed toward the water pump chamber side on the surface of the water pump shaft. A second synthetic resin made in sliding contact with the surface of the water pump shaft.
A groove-shaped first rigid member that is fitted to the inner diameter side of the core of the first seal member so as to sandwich the second seal member between the first seal member and the seal member. And when the first seal member is fitted on the inner diameter side of the core metal and fitted on the water pump shaft, the inner diameter side is elastically deformed toward the water pump chamber side on the surface of the water pump shaft to form the water pump. A third seal member made of synthetic resin that slides on the shaft surface, a cylindrical portion fitted with an inner peripheral surface of the metal core of the first seal member by appropriately forming a drainage hole in the circumferential direction and The third sheet comprising a flange formed toward
A second rigid member for sandwiching a water member between the first rigid member and the first rigid member.
The synthetic resin of the second seal member and the third seal member is made of polytetrafluoroethylene, the first rigid member and the second rigid member are made of metal, and the end of the second rigid member is a water pump. Characterized by being mounted on the outer ring of a bearing for a vehicle.

Alternatively, a sealing device for a water pump according to the present invention is a first type wherein a rubber material is fixed around a metal core.
The seal member is fitted into the inner diameter side of the core of the first seal member, and the inner diameter side is fitted with the water when fitted to the water pump shaft.
A second synthetic resin seat that elastically deforms on the surface of the water pump shaft toward the water pump chamber and slides on the surface of the water pump shaft.
A seal member, a groove-shaped first rigid member fitted into the core inner diameter side of the first seal member so as to sandwich the second seal member between the first seal member, When the first seal member is fitted on the inner diameter side of the cored bar and fitted on the water pump shaft, the inner diameter side is elastically deformed on the surface of the water pump shaft toward the water pump chamber and the surface of the water pump shaft. A third seal member made of synthetic resin, which slides on the third seal member; and a cylindrical portion fitted with the inner peripheral surface of the core bar of the first seal member by appropriately forming a drainage hole in the circumferential direction. A second rigid member, comprising a formed flange portion, for holding the third seal member between the first rigid member and the second rigid member; The surface of the water pump shaft is elastically deformed outward (toward the water pump chamber) to closely contact the water pump bearing surface and the first A fourth seal member made of felt seal for bringing the side surface into contact with the outer side surface of the seal member, and the fourth seal member having an L-shaped cross section on the outer side surface of the first seal member; A third rigid member for integrally fixing the water member, and a water pump sealing device comprising:
The synthetic resin of the second seal member and the third seal member is made of polytetrafluoroethylene, the first rigid member and the second rigid member are made of metal, and the end of the second rigid member is a water pump. Characterized by being mounted on the outer ring of a bearing for a vehicle.

[0007] Alternatively, the third seal member may be thinner than the second seal member.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial sectional view of a water pump provided with a water pump sealing device of the present invention, and FIG. 2 is a partially enlarged view of the water pump sealing device. In order to avoid redundant description, the same elements will be described using the same reference numerals as those described in the related art. A water pump shaft 1 that is rotationally driven by a drive source (not shown) is supported by a housing 2 via a water pump bearing 3. A boss 5b having an impeller 5a attached to an end thereof is fixed to the water pump shaft 1.
The impeller 5a rotates in the water pump chamber 4. The water pump bearing 3 and the water pump chamber 4
A sealing device 6 for a water pump is arranged between the two.

[0009] As shown in FIG.
When the first seal member 7 formed of a V-shaped core metal 7a and a rubber material 7b is fitted to and slidably contacted with the water pump shaft 1, the inner diameter side is outside on the surface of the water pump shaft 1 (water pump). A second seal member 8 made of a synthetic resin, for example, a polytetrafluoroethylene resin (hereinafter referred to as PTFE resin), which is elastically deformed toward the chamber side and adheres to the surface of the water pump shaft 1.
And an L-shaped metal core 7 of the first seal member 7 such that the second seal member 8 is sandwiched between the first seal member 7 and the second seal member 8.
a A first rigid member 9 of a groove-shaped cross section (not limited to a groove type) which is press-fitted into the inner peripheral surface or fitted with a small gap, and whose inner diameter side is fitted and slidably contacted with the water pump shaft 1. A third seal member 10 made of a synthetic resin, for example, PTFE resin, which elastically deforms outward (toward the water pump chamber) on the surface of the water pump shaft 1 and closely adheres to the surface of the water pump shaft 1;
The first seal member 7 is provided with a drain hole 11c in the circumferential direction.
A cylindrical portion 11a press-fitted into the inner peripheral surface of the L-shaped core metal 7a or fitted with a slight gap, and a flange portion 11 radially inward.
b, a second rigid member having an L-shaped cross section for sandwiching the third seal member 10 with the first rigid member 9;
It consists of.

The first seal member 7 is manufactured by baking and fixing a rubber member 7b to an L-shaped core bar 7a such as a steel plate. PT
The second seal member 8 and the third seal member 10 made of FE are formed by LLC (Lon) due to the chemical stability of PTFE.
g Life Coolant) and the fact that they have abrasion resistance under a constant water pressure and utilize these properties. The second seal member 8 has a function of strengthening the sealing because it is elastically deformed outward (water side) when receiving a pressure from the water side, and has a sealing performance together with the third seal member. It will be even more reliable. It is preferable that the third seal member 10 is slightly thinner than the second seal member so as to have a followability from the viewpoint of sealing performance. The first rigid member 9 has a function as a backup member for preventing the second seal member 8 from deforming and sagging when pressure is applied to the second seal member 8. In addition, a metal such as a steel plate or a ceramic or a resin having high rigidity can be used. Further, the first rigid member 9 has a function of holding the second seal member 8 and the third seal member 10 at an appropriate position without interfering with each other by forming a groove-shaped backup member. Have. The second
The end of the cylindrical portion 11a of the rigid member 11 is press-fitted to the outer ring 31 of the water pump bearing 3. The outer ring 31 is provided with a groove 31a, and a seal member 12 of a leap type is provided between the outer ring 31 and the water pump shaft 1.

Next, a drain hole 11c formed in the second rigid member 11 is for discharging water that has entered the space 16, and a drain passage (not shown) is provided in the case 2 side. ) To discharge to the outside. The second seal member 8 contains carbon fiber and graphite as fillers. In this case, the amount of the carbon fiber to be blended is preferably 20% by weight or less, and the amount of graphite is preferably 5% by weight or less. Under water-lubricated conditions, the carbon fibers do not decrease in pressure, and the above weight is optimal, and if mixed more, the carbon fiber becomes hard and brittle as a seal member, and the seal performance also deteriorates. In addition, graphite is effective as a solid lubricant at the time of low lubrication, but when the blending amount is increased to 5% by weight or more, it becomes hard and brittle,
Sealing performance is degraded.

As shown in FIG. 3, the sealing device 6 for a water pump having the above-described structure is provided with a metal core 7 of a first seal member 7.
a The second seal member 8 made of PTFE resin is fitted on the inner diameter side, and then the first rigid member 9 is fitted on the inner diameter side of the metal core 7a, and the second seal member 8 made of PTFE resin is inserted. Then, the third seal member 10 is connected to the metal core 7 of the first seal member 7.
a second rigid member 11 is fitted on the inner diameter side of the core 7a of the first seal member 7 so that the third seal member 10 is sandwiched between the third seal member 10 and the first rigid member 9. Into a unit (ASSEMBLY). The sealing device 6 of the water pump which has been unitized in advance in this way is
At the time of assembling the water pump, the rigid member 11 can be fixed simply by fitting it to the outer ring 31 of the bearing 3, so that not only the number of assembling steps is reduced but also the assembling work becomes extremely easy.

FIG. 4 is a partial sectional view of a second embodiment of the water pump sealing device 6 of the present invention. As shown in FIG. 4, the sealing device 6 of the water pump has a first seal member 7 formed of an L-shaped core 7a and a rubber member 7b.
And the inner surface is elastically deformed outward (toward the water pump chamber) on the surface of the water pump shaft 1 when the water pump shaft 1 is brought into sliding contact with the water pump shaft 1 so that the inner surface of the water pump shaft 1 is in close contact with the water pump shaft 1 The second seal member 8 made of resin, for example, PTFE resin, and the L of the first seal member 7 is sandwiched between the second seal member 8 and the first seal member 7. A first rigid member 9 having a groove-shaped cross section (not limited to a groove shape) which is press-fitted into the inner peripheral surface of the U-shaped core bar 7a or fitted with a slight gap, and is brought into sliding contact with the water pump shaft 1. When the inner diameter side is outside the surface of the water pump shaft 1 (water pump chamber side)
A third seal member 10 made of a synthetic resin, for example, PTFE resin, which is elastically deformed and adheres to the surface of the water pump shaft 1.
A water drain hole 11c is formed in the circumferential direction, and is press-fitted into the inner peripheral surface of the L-shaped core metal 7a of the first seal member 7 or fitted radially inward with the cylindrical portion 11a fitted with a slight gap. Forming a flange portion 11b, and connecting the third seal member 10 to the first seal member 10b.
A second rigid member having an L-shaped cross section sandwiched between the rigid member 9 and an inner diameter side of the second rigid member having an L-shaped cross section when the sliding member is brought into sliding contact with the water pump shaft 1 is located outside the surface of the water pump shaft 1 (toward the water pump chamber). The fourth seal made of felt seals elastically deforms to adhere to the water pump bearing surface and to make the side surface 14a contact and adhere to the outer end surface of the first seal member 7.
And a third rigid member 13 having an L-shaped cross section and integrally fixing the fourth seal member 14 to the outer end surface of the first seal member 7. You.

The felt material of the fourth seal member 14 is a seal that does not allow foreign substances having a size of 0.5 to 1.0 μ or more to pass therethrough and allows cooling water to pass therethrough. As a material, PPS (polyphenylene sulfide) or the like is preferable in consideration of water resistance and made of resin. The resin content for improving the abrasion resistance of the felt is preferably 30% by weight. In addition, the fourth seal member 14 made of felt is connected to the first seal member.
The outer end surface of the screw member 7 is integrated with the second rigid member 9 and is fixed between them by using an adhesive.

The sealing device 6 for a water pump having the above-described structure is constructed such that PTFE is provided on the inner side of the core 7a of the first seal member 7.
A second seal member 8 made of resin is fitted, and then a first rigid member 9 is fitted on the inner diameter side of the core bar 7a to clamp the second seal member 8 made of PTFE resin. 3 seal member 1
0 is fitted on the inner diameter side of the core bar 7a, and the second rigid member 11 is fitted on the inner diameter side of the first seal member 7a so as to sandwich the third seal member. The fourth sealing member 14 made of felt is fixed to the outer end surface of the sealing member 7 with the third rigid member 13 and assembled to form a unit (ASSEM).
BLY).

[0016]

As described above in detail, the warp of the present invention is described.
According to the sealing device of the water pump, since the seal members do not slide with each other, water leakage can be prevented even if foreign matter is mixed in the cooling water. The second seal member and the third seal member that are in contact with the water pump shaft have PTFE.
Since a chemically and physically stable resin is used, it is possible to provide a water pump sealed structure having high followability and high reliability. Further, since the second seal member has a structure in which foreign matters do not come due to the fourth seal member made of felt, abnormal wear hardly occurs. Therefore, since the sealing device for the water pump is unitized in advance and attached to the outer ring of the bearing, the assembling work becomes extremely easy.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a water pump provided with a water pump sealing device of the present invention.

FIG. 2 is a partially enlarged view of the first embodiment of the water pump sealing device of the present invention.

FIG. 3 is an exploded view showing a procedure for assembling the first embodiment of the water pump sealing device of the present invention.

FIG. 4 is a partially enlarged view of a second embodiment of the water pump sealing device of the present invention.

FIG. 5 is a partial sectional view of a water pump provided with a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water pump shaft 2 Housing 3 Water pump bearing 4 Water pump chamber 5 Impeller 6 Sealing device 7 First seal member 7a Core 7b Rubber material 8 Second seal member made of PTFE resin 9 First Rigid member 10 Third seal member 10a Core 10b Rubber material 11 Second rigid member 13 Third rigid member (Second embodiment) 14 Fourth seal member (Second embodiment)

Claims (3)

[Claims] 1. A first seal member formed by fixing a rubber material around a metal core, and a first seal member is fitted to the inner diameter side of the metal core and fitted to a water pump shaft. At this time, the inner side is elastically deformed toward the water pump chamber on the surface of the water pump shaft, and slides on the surface of the water pump shaft.
A groove-shaped first rigid member that is fitted to the inner diameter side of the core of the first seal member so as to sandwich the second seal member between the first seal member and the seal member. And when the first seal member is fitted on the inner diameter side of the core metal and fitted on the water pump shaft, the inner diameter side is elastically deformed toward the water pump chamber side on the surface of the water pump shaft to form the water pump. A third seal member made of synthetic resin that slides on the shaft surface, a cylindrical portion fitted with an inner peripheral surface of the metal core of the first seal member by appropriately forming a drainage hole in the circumferential direction and The third sheet comprising a flange formed toward
A second rigid member sandwiching the sealing member between the first rigid member and the second rigid member, wherein the synthetic resin for the second sealing member and the third sealing member is provided. Wherein the first rigid member and the second rigid member are made of metal, and ends of the second rigid member are attached to the outer ring of a water pump bearing. Sealing device. 2. A first seal member formed by fixing a rubber material around a core bar, and the first seal member is fitted on the inner diameter side of the core bar and fitted to a water pump shaft. At this time, the inner side is elastically deformed toward the water pump chamber on the surface of the water pump shaft, and slides on the surface of the water pump shaft.
A groove-shaped first rigid member that is fitted to the inner diameter side of the core of the first seal member so as to sandwich the second seal member between the first seal member and the seal member. And when the first seal member is fitted on the inner diameter side of the core metal and fitted on the water pump shaft, the inner diameter side is elastically deformed toward the water pump chamber side on the surface of the water pump shaft to form the water pump. A third seal member made of synthetic resin that slides on the shaft surface, a cylindrical portion fitted with an inner peripheral surface of the metal core of the first seal member by appropriately forming a drainage hole in the circumferential direction and The third sheet comprising a flange formed toward
A second rigid member having an L-shaped cross section for holding a water member between the first rigid member and the second rigid member having an L-shaped cross section; The first seal member is made of a felt seal which is elastically deformed to be in close contact with the surface of the water pump bearing and is in close contact with the outer side surface of the first seal member.
A water pump sealing device comprising: a seal member; and a third rigid member integrally fixing the fourth seal member to an outer side surface of the first seal member. The synthetic resin of the second seal member and the third seal member is made of polytetrafluoroethylene, the first rigid member and the second rigid member are made of metal, and the end of the second rigid member is for a water pump. A sealing device for a water pump, which is mounted on an outer ring of a bearing. 3. The water pump sealing device according to claim 1, wherein the third seal member has a smaller thickness than the second seal member.