JPS61200391A - Scroll type fluid machinery - Google Patents

Abstract

PURPOSE:To make it possible to effectively cool the bearings and a motor portion of scroll type fluid machinery through a driving rotary shaft by forming a circulating path for cooling water in the driving rotary shaft of the scroll type fluid machinery. CONSTITUTION:The inside of the driving rotary shaft 4 of scroll type fluid machinery is formed into a cavity into which a pipe 16b is inserted, and the end of the above shaft 4 is covered with a closing plate 12. The pipe 16b extrudes from the lower end of the driving rotary shaft 4, and its extruding portion is connected with a feeding pipe joint 16 for cooling water. In addition, the lower end of the driving rotary shaft 4 is connected with a discharging pipe joint 15 for cooling water. Accordingly, the cooling water fed into the pipe 16b overflows from the pipe 16b into the driving rotary shaft 4 at the upper end of the above shaft 4, and flows between the pipe 16b and the inner peripheral wall of the driving rotary shaft 4 and then into a discharging pipe. Thus each member of the scroll type fluid machinery can be effectively cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling device for a scroll-type fluid machine.

[Conventional technology]

Recently, as a general type of scroll type fluid machine consisting of a fixed scroll, an orbiting scroll, a rotating shaft with a crankshaft, a casing, etc., there is a type as shown in Japanese Patent Application Laid-Open No. 59-58188 (see Fig. 4). (illustrated).

In this type of fluid machine, generally fixed scroll A
In the lap retaining chamber C where the wrap A1 of the orbiting scroll B meshes with the wrap B1 of the orbiting scroll B, high temperature heat is generated due to fluid confinement compression. Due to the flapping phenomenon of the orbiting scroll B due to the position of the center of gravity being deviated from the center of the orbiting bearing, and various other reasons, a large load is constantly applied to the orbiting bearing, and as a result, the vicinity of the bearing also becomes high temperature.

However, normally the back chamber E of the orbiting scroll B is filled with air.1. Therefore, the heat of the swing bearing part is transmitted through the air in the back chamber E and radiated to the outside from the casing F, and the heat of A3 in the lap engagement chamber C is radiated to the outside from the wall of the fixed scroll A. In addition, although not shown, atomized lubricating oil is circulated in various internal parts by appropriate means for the purpose of lubrication and cooling, thereby achieving cooling of the high-temperature parts.

[Problem that the invention seeks to solve]

In the scroll-type fluid machine of the conventional configuration described above, cooling is performed to some extent, although it is insufficient, but when this type of fluid machine is operated as an oil-free vacuum pump with the orbiting scroll back chamber E also being vacuumed, Since the air in this chamber E is thin, heat dissipation is cut off, and in addition, there is no cooling with lubricating oil, which causes various problems such as expansion and deformation of various parts due to high heat, resulting in decreased performance and shortened lifespan. , it is impossible to use it unless some kind of cooling means is provided.

[Means for solving problems]

The rotating shaft is also used as a motor shaft and is hollow almost to the crankshaft end, and a shaft sealing device is installed between the motor shaft end side of the rotating shaft and an end fitting with a cooling water inlet and outlet attached to the casing cover. The motor room and the cooling water outlet chamber are isolated from each other, and the cooling water inlet is provided with a pipe extending to the vicinity of the end of the crankshaft, and the pipe is inserted into the hollow part of the rotating shaft with a gap between them, and the cooling water flowing in from the inlet is inserted into the hollow part of the rotating shaft. The cooling system is characterized in that the cooling system is reversed at the tip of the pipe, flows backward through the gap between the pipe and the rotating shaft, and reaches the outlet.

[For production]

The cooling water flowing in from the cooling water inlet passes through the pipe, reaches the tip of the crankshaft, cools the swing bearing through the thickness of the crankshaft, and then reverses and flows back between the pipe and the rotating shaft including the crankshaft. As a result, not only the swing bearing is actively cooled, but also the rotating shaft bearing and the motor portion that cause heat generation through the rotating shaft are cooled, and the cooling water that has absorbed heat reaches the outlet section. The cooling water is isolated from the bearing and the motor chamber at the shaft sealing device, and there is no risk of causing any trouble.

〔Example〕

To explain the embodiment shown in FIGS. 1 to 8, 1 is a fixed scroll which also serves as an upper cover, and has a wrap 1a facing downward and an intermediate casing 2 connected to the lower surface. motor casing 3
are connected.

4 is a rotating shaft with a crankshaft, the upper part of which is supported by a bearing 5 on the intermediate casing 2, and the lower part supported by a bearing 7 on a lower cover 6 provided at the lower end of the motor casing 3; 4a is integrally formed with a through hole 4b extending over the entire length to form a hollow rotating shaft.
a, the wrap 8a is engaged with the wrap 1a of the fixed scroll 1, and the end plate part is provided with a thrust bearing 10 between it and the upper wall of the intermediate casing 2, and is rotated by an appropriate number of pin cranks 11. The rotary shaft 40 rotates to perform the rotation movement.

Reference numeral 12 designates a cover plate which also serves as a bearing plate and is provided at the end of the crankshaft 4a and is fixed to the crankshaft 4a with bolts 18.

Reference numeral 14 denotes a motor fitted into the motor casing 3, and the rotary shaft 4 serves as the motor shaft.

Reference numeral 15 denotes an end fitting fixed to the lower cover 6, which has a cooling water outlet 15a on the side and a joint 16 with a cooling water inlet 16a screwed onto the lower part. A pipe 16b is integrally erected and fixed so as to communicate with the water inlet 16a, and the pipe 16b is inserted into the through hole 4b of the rotating shaft 4 and extends slightly in front of the cover plate 12, and the outer diameter and the through hole are fixed. 4b is arranged so as to have a gap between it and the wall surface.

Reference numeral 17 denotes a mechanical seal as a shaft sealing device interposed between the bearing 7, the lower part of the rotating shaft 4, and the end fitting 15. An O-ring 18 is provided between the end fitting 15 and the cooling water outlet 15a. This serves as a barrier between the bearing 7 and the motor 14.

A7 The fixed scroll intermediate casing 2 and motor casing 3 each have a water jacket 1 around the entire circumference.
b, 2a, and 3a are provided to connect these, and
The lower cover 6 is provided with a through hole 6a, and the cooling water outlet 15 is provided with a through hole 6a.
A communication pipe 19 is connected between the hole 6a and the through hole 6a. Therefore, the cooling water flowing into the pipe 1 from the cooling water inlet 16a
6b, and then reversed at the upper end to form the pipe 16b.
It descends inside the through hole 4b on the outer periphery and reaches the cooling water outlet 15a, and then from inside the communication pipe 19 to each water jacket 1b.
- After passing through 2a and 3a sequentially, the liquid flows out to the outside through an upper outlet 1 (!J) provided in the fixed scroll 1.

In addition, 20 shows a balance weight, 21 shows a shaft seal, and 22 shows a counterweight.

Next, the effect will be explained. Due to the rotation of the rotating shaft 4 with a crankshaft, the orbiting scroll 8 performs a rotating movement around the rotating shaft 8, and as a result, the wraps 1a and 8a are engaged to sequentially compress the fluid sucked in from the suction port 1d and discharge it. Exit 1
A compression action is performed to discharge from e.

In this case, a separately provided cooling water pressure source (not shown) is connected to the cooling water inlet 16a.
6a, l:p The cooling water that has flowed in rises in the pipe 16b, reaches the top of the pipe 16b, flows out of the pipe, and then reverses itself and descends in the through hole 4b. This flow of cooling water sequentially cools high-temperature parts such as the swing bearing 9, the bearing 5, and the motor 14 through the thickness of the crankshaft 4a and the rotating shaft 4. Thus, the cooling water reaches the cooling water outlet 15a, and further passes through the communication pipe 19 through the water jackets 8a, etc. 2a, l.
b, and flows out to the outside through the upper outlet port 1c while cooling the entire outer surface of the fluid machine. Therefore, when used as an oil-less vacuum pump, the back chamber of the orbiting scroll 8 is also evacuated. Even if there is, high-temperature parts such as the swing bearing 9, the bearing 5, and the motor 14 are effectively cooled by the constantly replaced cooling water.

In the above embodiment, water jackets 1b and 2a
・In 3a, the outside of the fluid machine is also cooled, but it is not limited to this. It is possible to cool only the center, or to introduce cooling water pressure sources separately for the center and the outside. It's okay.

〔Effect of the invention〕

In the present invention, the rotary shaft with a crankshaft is made hollow so that it can also be used as a motor shaft, and a pipe communicating with the cooling water inlet is installed in the hollow part, so that the cooling water is reversed at the crankshaft part and the shaft is rotated outside the pipe. High temperature slewing bearing when descending inside,
Since the rotating shaft bearing and motor part are cooled,
Even if the back of the orbiting scroll is used in a vacuum state as an oil-less vacuum pump as well as a normal scroll-type fluid machine, each part can be sufficiently cooled, so there is no risk of abnormal expansion or distortion of each part due to high temperature. However, it is possible to create a stable and high-performance machine.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing one embodiment of the present invention, Figs. be. In the figure, 1 is a fixed scroll, 2 is an intermediate casing, 3 is a motor casing, 4 is a rotating shaft with a crankshaft, 4a is a crankshaft, 6 is a lower cover, 8 is an orbiting scroll, 1
4 is a motor, 15 is an end fitting, 15a is a cooling water outlet, 1
6 is a joint, 16a is a cooling water inlet, 16b is a pipe, 17
indicates a mechanical seal.

Claims (1)

[Claims] (1) In a scroll consisting of a fixed scroll, an orbiting scroll, a rotating shaft with a crankshaft, and a casing, the rotating shaft is also used as a motor shaft and is hollow almost to the end of the crankshaft, and the motor shaft end side of the rotating shaft is covered with a casing cover. A shaft sealing device is provided between the end fitting with the cooling water inlet and outlet attached to the motor chamber to isolate the motor chamber and the cooling water outlet chamber, and a pipe is installed at the cooling water inlet to reach the vicinity of the end of the crankshaft. The pipe is inserted into the hollow part of the rotating shaft with a gap, and the cooling water flowing in from the inlet is reversed at the tip of the pipe,
A scroll-type fluid machine characterized in that a cooling system is formed such that the flow flows backward through the gap between the pipe and the rotating shaft and reaches the outlet.