JP2002139061A - Cooled bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooled bearing device securing a sufficient strength of a bearing member in the case a cooling jacket is installed inside the bearing and preventing a cooling medium from stagnating inside the jacket to lead to a drop of the thermal efficiency. SOLUTION: The cooled bearing device is structured so that each bearing 8 to support a shaft 7 rotatably is furnished with a cooling medium passage 13, wherein the passage 13 is composed of a ring-shaped space 14 formed inside the bearing 8 and a partitioning wall 15 installed inside the ring-shaped space 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling bearing device used for a gear pump for conveying molten resin.

[0002]

2. Description of the Related Art A gear pump for conveying molten resin is provided with a rotor having a pair of meshing gears.
A sliding bearing is employed as a bearing for the rotor. This bearing is cooled to increase the load capacity. As this cooling bearing device, it is common to arrange a hollow jacket inside the bearing and flow a cooling medium through the hollow jacket. However, in the molten resin conveying gear pump, a part of the conveyed molten resin flows through the bearing portion to lubricate the bearing, and the pressure of the lubricating resin is 1,000 kgf / cm ² depending on the type and operating conditions. And may be as high as 400 ° C. or higher. Under such severe conditions, especially inside the bearing,
The mere provision of the hollow jacket causes a problem that the wall thickness of the bearing portion becomes thin and cannot withstand the resin pressure and thermal stress.

In order to reduce the stress of the bearing portion, there is a method of increasing the thickness of the bearing portion by moving the jacket in the outer peripheral direction. However, the cooling medium is further away from the lubricating resin, so that the cooling efficiency is reduced. There was a problem. On the other hand, as a cooling bearing device of this type, for example, Japanese Unexamined Patent Publication No.
The thing described in 21768 gazette is publicly known. In this cooling bearing device, as shown in FIG. 8, holes 30 extending in the axial direction are provided at equal intervals in the circumferential direction of the bearing portion, and adjacent ones of the holes 30 at one end of the hole 30 are formed in the circumferential direction. The meandering cooling medium passage 33 is formed by communicating with the groove 31 and closing the other end with the closing member 32.

[0004]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 9-217 is disclosed.
In the structure disclosed in JP-A-68-68, the hole constituting the jacket must be reduced in order to secure the strength of the bearing, and there is a problem that a sufficient cooling effect cannot be obtained.
In order to increase the cooling effect, it is conceivable to increase the number of holes through which the cooling medium passes. However, simply increasing the number of holes increases the pressure loss of the cooling medium. There was a problem that it became weaker.

Accordingly, the present invention has solved the problem of insufficient strength of the bearing member when the cooling jacket is provided inside the bearing, and has solved the problem that the cooling medium stays inside the jacket and the thermal efficiency is reduced. It is an object to provide a cooling bearing device.

[0006]

In order to achieve the above object, the present invention takes the following measures. That is, a feature of the present invention is that in a cooling bearing device in which a cooling medium passage is provided in a bearing that rotatably supports a shaft portion, the cooling medium passage has an annular space formed inside the bearing. ,
And a partition wall provided in the annular space. According to the present invention having the above-described configuration, the flow resistance of the cooling medium flowing in the annular space can be reduced depending on how the partition wall is provided, so that the cooling efficiency can be increased.

[0007] Further, since the partition wall can function as a reinforcing member, it is possible to minimize a decrease in strength of the bearing even if the annular space is enlarged. Further, since the reduction in strength can be suppressed, the annular space can be made closer to the inner peripheral surface side of the bearing portion, and the cooling efficiency can be increased. The partition wall is preferably provided in a spiral shape. Preferably, the cooling medium passage formed by the spiral partition wall is a double spiral groove.

[0008] The partition wall may be constituted by a circumferential partition wall extending in the circumferential direction and an axial partition wall extending in the axial direction. Preferably, the annular space is surrounded by an inner peripheral surface and an outer peripheral surface, and the partition wall is formed between the inner and outer peripheral surfaces. With such a configuration, the function of the partition wall as a reinforcing member is sufficiently exhibited. The bearing is formed by integrally connecting an inner peripheral member and an outer peripheral member formed of separate members, and the cooling medium passage is formed at a boundary between the inner peripheral member and the outer peripheral member. Is preferred. By employing such a configuration, formation of the cooling medium passage is facilitated.

It is preferable that the partition wall is formed integrally with either the outer peripheral member or the inner peripheral member. Further, among the partition walls, at least the axial partition wall is formed of a separate member from the outer peripheral member and the inner peripheral member, and is coupled to at least one of the side members in the annular space. Can be adopted.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. The gear pump shown in FIGS. 1 to 3 is a gear pump for quantitatively transferring the molten resin in the kneading and granulating system. This gear pump has a block-shaped body 1, a glasses-shaped rotor housing hole 2 is formed through the body 1, and resin inlets are provided on both sides of the rotor housing hole 2 through the rotor housing hole 2. 3 and an outlet 4 are formed.
The rotor housing hole 2 houses a pair of rotors 5 and 5. The rotor 5 includes a gear portion 6 and shaft portions 7 formed on both sides of the gear portion 6. The gear portion 6 is always meshed, and the shaft portion 7 is rotatably supported by a slide bearing 8 fitted in the rotor housing hole 2. The bearing 8 is prevented from falling out of the rotor housing hole 2 by a bearing retainer 10 fixed to the body 1 by bolts 9.

A seal member 11 is fixed to the bearing retainer 10, and the seal member 11 and the shaft portion 7 are prevented from flowing out of the molten resin by a labyrinth seal. One end of the shaft 7 of the rotor 5 is
The rotor 5 is driven to rotate in the direction of the arrow in FIG. 3, and the molten resin is conveyed from the resin inlet 3 to the outlet 4 by the gear unit 6. The sliding bearing 8 is configured as a cooling bearing device in which a cooling medium passage 13 is formed.

The cooling medium passage 13 includes an annular space 14 formed inside the bearing 8 and a partition wall 15 provided in the annular space 14. FIG.
Next, as shown in a development view in the circumferential direction,
Are provided spirally. With this partition wall 15,
In the annular space 14, a cooling medium passage 13 formed of two spiral grooves is formed, and the cooling medium inlet 1 is formed at an end of one of the grooves.
6 and a cooling medium outlet 17 is formed at the end of the other groove. The cooling medium inlet 16 and outlet 17
An inlet pipe 18 and an outlet pipe 19 penetrating the bearing retainer 10 and the seal member 11 are connected.
The inlet pipe 18 and the outlet pipe 19 are connected to a cooling medium supply device (not shown).

Since the cooling medium passage 13 has a double spiral groove structure, the inlet 16 and the outlet 17 can be provided close to each other. The cooling medium supplied to the inlet pipe 18 from the cooling medium supply device enters the spiral groove from the cooling medium inlet 16 and flows through the annular space 14 through the cooling medium passage 13,
After cooling the bearing 8, it is returned from the cooling medium outlet 17 through the outlet pipe 19 to the cooling medium supply device. Although oil is used as the cooling medium, the cooling medium is not limited to oil.

The bearing 8 is formed by integrally connecting an inner peripheral member 20 and an outer peripheral member 21 to each other.
The cooling medium passage 13 is formed at a boundary between the outer peripheral side member 21 and the cooling medium passage 13. In this embodiment, the inner peripheral member 20
An annular concave portion forming the annular space 14 is formed on the outer peripheral surface of the spiral partition wall 1 shown in FIG.
5 are integrally formed. And, this inner peripheral side member 20
The outer peripheral side member 21 is fitted into and integrated. This integration includes welding and welding after shrink fitting.

In the integrated state, the outer peripheral surface of the partition wall 15 is in contact with the inner peripheral surface of the outer peripheral member 21. That is, the annular space 14 is
And the outer peripheral surface of the annular concave portion of the inner peripheral member 20, and the partition wall 15 is formed between the inner and outer peripheral surfaces. Since the partition wall 15 is formed between the inner and outer peripheral surfaces of the annular space 14, the partition wall 15 functions as a reinforcing member. Therefore, even if the annular space 14 is enlarged, the reduction in bearing strength can be reinforced.

As shown in FIG. 1, the inner diameter of the annular space 14 is DJ, the outer diameter of the shaft portion 7 is DR, the height of the annular space 14 is h,
When the thickness of the partition wall 15 is W, it is preferable to satisfy the following relationship. 1.1DR ≦ DJ ≦ 1.4DR, preferably 1.2D
R ≦ DJ ≦ 1.3DR. 0.5h <W <1.5h. When the inner diameter DJ of the annular space 14 is smaller than 1.1DR,
The thickness of the bearing portion is reduced, and a problem of strength occurs. Also,
When it is larger than 1.4DR, the thermal efficiency is reduced. If the thickness W of the partition wall 15 is too large, the area of the passage 13 becomes small, so that the pressure loss of the cooling medium increases, and if it is too small, the effect as a reinforcing material is lost.

In this flow path structure, the cooling medium flowing into the cooling medium passage 13 from the cooling medium inlet 16 becomes a flow path that returns automatically after reaching the end in the axial direction, so that the flow is smooth. Heat efficiency is improved. In addition,
In the present invention, an annular concave portion may be provided in the inner peripheral surface of the outer peripheral member 21 and the partition wall 15 may be provided in the concave portion. Also,
It is not limited to the double spiral groove structure. FIG. 5 shows another embodiment of the present invention, in which a circumferential partition wall 15a extending in the circumferential direction is used instead of the spiral partition wall.
And an axial partition wall 15b extending in the axial direction.

That is, one axial partition wall 15b is provided in the annular space 14, and a plurality of circumferential partition walls 15a protruding from the side surface of the axial partition wall 15b form the cooling medium passage 13. I have. A cooling medium inlet 16 is connected to one end of the passage 13, and an outlet 17 is connected to the other end. FIG. 6 shows another embodiment of the present invention, in which two axial partition walls 15b are provided 180 degrees apart in the circumferential direction. Thus, by providing an even number of the axial partition walls 15b, the cooling medium inlet 1
6 and outlet 17 can be provided close to the same side.

In the flow channel structure shown in FIG.
The cooling medium flowing into the cooling medium passage 13 from 6 becomes a flow path that automatically returns after reaching the end in the axial direction, so that the flow is smooth and the thermal efficiency is improved.
That is, the temperature is about 140 ° C. in the vicinity of the inlet 16, about 150 ° C. in the middle, and about 160 ° C. in the outlet 17, so that the temperature of the cooling medium in the axial direction is averaged and uniform cooling can be achieved. As shown in FIG. 7, the number of the circumferential partition walls 15a is n, and the number of the circumferential partition walls 15a is n.
a is W1, the width of the cooling medium passage 13 formed by the adjacent circumferential partition walls 15a is W2, the width of the annular space 14 is W3, and the height of the annular space 14 is h. Is preferably satisfied.

W1 ≦ (1/2) · W2, n · W1 ≦ (1
/ 2) · W3, 0.5h <W1 By satisfying such a relationship, pressure loss of the cooling medium can be prevented, the cooling effect can be enhanced, and the partition wall 1
5 can exhibit the effect as a reinforcing rib. In each of the above embodiments, the spiral partition wall 15 and the axial and circumferential partition walls 15a and 15b are integrally cut from the inner peripheral member 20 to prevent fatigue due to a heat cycle. Preferred above. However, the partition walls 15 may be formed separately from the bearing 8 and integrally joined by spot welding or the like.

Further, the partition wall integrally cut and the partition wall separately connected may be combined. In this case, the circumferential partition wall 15a is integrally cut out, and the axial partition wall 15b is formed.
If they are separately formed, processing becomes easy. Note that the present invention is not limited to the embodiments described above.

[0022]

According to the present invention, the problem of insufficient strength of the bearing member when the cooling jacket is provided inside the bearing is solved, and the problem that the cooling medium stays inside the jacket and the thermal efficiency is reduced is solved. Can be solved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a gear pump according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a circumferential development of an annular space (cooling jacket).

FIG. 5 is a circumferential development of an annular space (cooling jacket) showing another embodiment.

FIG. 6 is a circumferential development of an annular space (cooling jacket) showing another embodiment.

FIG. 7 is a sectional view of an annular space.

FIG. 8 is a circumferential development view of a cooling jacket showing a conventional example.

[Explanation of symbols]

 7 Shaft 8 Bearing 13 Cooling medium passage 14 Annular space 15 Partition wall

Continued on the front page (72) Inventor Nobuki Nagami 2-3-1, Shinhama, Araimachi, Takasago City, Hyogo Prefecture Inside Kobe Steel, Ltd. Takasago Works (72) Inventor Kazuo Iriya 2-3-1, Shinama, Araimachi, Takasago City, Hyogo Prefecture Kobe Steel, Ltd. Takasago Works (72) Inventor Koji Okuma 2-3-1, Shinhama, Arai-machi, Takasago-shi, Hyogo F-term in Kobe Steel Works, Takasago Works 3J017 EA02 FA02 GA01

Claims (8)

[Claims] 1. A cooling bearing device in which a cooling medium passage is provided in a bearing that rotatably supports a shaft portion, wherein the cooling medium passage is formed in an annular space formed inside the bearing and in the annular space. A cooling bearing device comprising a partition wall provided. 2. The cooling bearing device according to claim 1, wherein the partition wall is provided in a spiral shape. 3. The cooling bearing device according to claim 2, wherein the cooling medium passage formed by the spiral partition wall is a double spiral groove. 4. The cooling bearing device according to claim 1, wherein the partition wall includes a circumferential partition wall extending in a circumferential direction and an axial partition wall extending in an axial direction. 5. The annular space is surrounded by an inner peripheral surface and an outer peripheral surface, and the partition wall is formed between the inner and outer peripheral surfaces. A cooling bearing device according to one of the preceding claims. 6. The bearing is formed by integrally connecting an inner peripheral member and an outer peripheral member, which are separate members, and the cooling medium passage is provided at a boundary between the inner peripheral member and the outer peripheral member. The cooling bearing device according to any one of claims 1 to 5, wherein the cooling bearing device is formed. 7. The cooling bearing device according to claim 6, wherein the partition wall is formed integrally with one of the outer peripheral member and the inner peripheral member. 8. The partition wall, wherein at least the axial partition wall is formed of a separate member from the outer peripheral member and the inner peripheral member, and at least one of the side members in the annular space. 7. The cooling bearing device according to claim 6, wherein the cooling bearing device is coupled to the cooling bearing device.