JPS6343427Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a scroll compressor in which an axial fan is provided within a casing to effectively cool an orbiting scroll and bearings.

Conventionally, there has been known a scroll compressor which comprises a fixed scroll fixed to a casing, a drive shaft which is rotatably supported by the casing and has one end which is a rotating shaft extending linearly from a motor and the other end which is a crankshaft, and a revolving scroll which is rotatably supported by the crankshaft portion of the drive shaft, and which is configured so that by revolving the revolving scroll relative to the fixed scroll, air sucked in through an intake port is compressed and discharged from a discharge port.

However, the reality is that in such conventional scroll compressors, no cooling method is employed other than opening the inside of the casing to the outside. For this reason, in an oil-free scroll compressor that does not supply oil into the compression chamber, compression heat is generated by the compression action, and this heat of compression is transferred to each scroll member and thermally expands, causing each scroll member to come into contact with each other. This may cause Conventionally, a method of increasing the clearance between scroll members has been used to avoid such contact, but with this method, when the discharge pressure during compression is low, the temperature rise is small, so the compression efficiency is reduced. The disadvantage was that it decreased. On the other hand, in the oil-free scroll compressor mentioned above, bearings are filled with lubricant such as grease, but when the bearing temperature rises, the lubricant deteriorates prematurely or leaks from the bearing sealing member. However, there was a drawback that caused damage to the bearing.

The present invention was devised in view of the problems of the prior art, and by disposing an axial fan in the casing and sending cooling air to the back side of the orbiting scroll, the invention directly cools the orbiting scroll. An object of the present invention is to provide a scroll compressor that can effectively cool a drive shaft, a first bearing that pivotally supports an orbiting scroll, and a second bearing that pivotally supports an orbiting scroll.

In order to achieve this object, the present invention includes a cylindrical casing having a fan chamber formed therein and having at least one side open, a fixed scroll fixedly provided on the open side of the casing, and a fixed scroll fixed to the open side of the casing. A motor attached to the other side, a drive shaft extending axially from the motor into the casing and having a tip end serving as a crankshaft, and a first drive shaft for pivotally supporting the base end of the drive shaft in the casing. a bearing, an orbiting scroll arranged in a fan chamber so as to overlap with the fixed scroll to form a compression chamber, and a second bearing for pivotally supporting the orbiting scroll on a crankshaft at the tip of the drive shaft. an axial flow fan located between the first and second bearings and fixed to the drive shaft so as to send cooling air directly to the back side of the orbiting scroll; an intake port formed in the casing located closer to the motor than the axial fan so as to communicate with the casing, and an intake port located closer to the orbiting scroll than the axial fan so as to communicate the fan chamber with the outside; an exhaust port formed in the fan chamber, a suction port provided in the orbiting scroll to suck air from the fan chamber into the compression chamber and closed by a dust intrusion prevention filter, and air compressed in the compression chamber. and a discharge port provided on the fixed scroll for discharging.

With this configuration, while the external air taken in from the intake port by the rotation of the axial fan is sent to the back side of the orbiting scroll and exhausted from the exhaust port,
In addition to cooling the orbiting scroll and the first and second bearings, air inside the fan can be sucked in from the suction port through the filter, so even when a filter is provided at the suction port, the compression chamber remains under negative pressure. The situation can be prevented.

The present invention will be described below along with embodiments shown in the drawings.

In the drawings, reference numeral 1 denotes a cylindrical casing with a bottom, and inside the casing 1 there is formed a fan chamber 2 which is open on one side in the axial direction, and a bearing hole 1B is formed in a boss part protruding from a bottom plate 1A. has been done.

A fixed scroll 3 is fixedly provided to the casing 1 so as to close the opening side of the fan chamber 2. Here, the fixed scroll 3 has an end plate 3A.
and a wrap portion 3 erected on one side of the mirror plate 3A.
B, and a radiation fin 3C formed on a surface facing the wrap portion 3B, and the wrap portion 3B is formed in an involute or a spiral shape close to an involute. A discharge port 4 is formed at the center of the mirror plate 3A.

In addition, a motor 5 is mounted on the bottom plate 1A side of the casing 1.
The motor 5 is provided with a drive shaft 6 protruding into the fan chamber 2 of the casing 1 . Here, the drive shaft 6 is formed integrally with a rotating shaft 6A extending linearly from a rotor (not shown) of the motor 5 and serving as a base end, and at a distal end of the rotating shaft 6A, It consists of a crankshaft 6B extending into the fan chamber 2, and the axis of the rotating shaft 6A and the axis of the crankshaft 6B are eccentric by a distance δ, and the rotating shaft 6A is coaxial with the fixed scroll 3. It is designed to be the heart.

7 and 7 are bearings such as angular ball bearings,
The outer ring of the bearing 7 is press-fitted into the bearing hole 1B of the casing 1, and the inner ring is press-fitted into the rotating shaft 6A, so that the drive shaft 6 is moved in the axial direction with respect to the casing 1.
It is mounted so that it cannot be displaced in the radial direction. The bearing 7 is, for example, a front-to-front combination bearing or a back-to-back combination bearing as shown in the figure.The bearing 7 is filled with lubricating oil, and its open end is sealed by an oil seal 8.

Next, reference numeral 9 denotes an orbiting scroll provided on the same axis as the crankshaft 6B, and the orbiting scroll 9 includes an end plate 9A, a lap portion 9B provided upright on one side of the end plate 9A, and the wrap portion 9B. If it is from the bearing hole 9C formed on the opposing surface, the wrap portion 9B
It is also formed in an involute or a spiral shape close to an involute, and a suction port 10 is provided at the end of the end plate 9A. And the lap part 9
B is attached so as to overlap the lap part 3B of the fixed scroll 3 at a predetermined angle shift, and a plurality of compression chambers 11 are formed between each of the lap parts 3B and 9B. It is configured to compress the air sucked in from the compressor and discharge it from the discharge port 4. In the figure, 12 is a filter for blocking the suction port 10 to prevent dust from entering.

13, 13 are bearings such as angular ball bearings like the bearing 7, and the outer ring of the bearing 13 is press-fitted into the bearing hole 9C of the orbiting scroll 9, and the inner ring is attached to the crankshaft 6.
By being press-fitted into B, the orbiting scroll 9 is attached to the crankshaft 6B so as not to be displaceable in the axial and radial directions. The bearing 13 is also a front-to-back combination bearing or a back-to-back combination bearing, for example, and the inside of the bearing 13 is filled with lubricant, and the open end of the bearing hole 9C is sealed with an oil seal 14.

On the other hand, 15 is a plurality of auxiliary cranks provided at different positions between the fixed scroll 3 and the orbiting scroll 9, and the auxiliary cranks 15 have a distance between the axis of the fixed scroll 3 and the axis of the orbiting scroll 9. It is eccentric by δ, and when the drive shaft 6 rotates, the orbiting scroll 9 revolves around the axis of the fixed scroll 3 with a radius δ by the auxiliary crank 15.

Next, 16 is an axial flow fan provided in the fan chamber 2, and the axial flow fan 16 includes a boss portion 16A fixed to the rotating shaft 6A between the bearings 7 and 13, and a plant around the boss portion 16A. Multiple blades installed 1
It consists of 6B, 16B,...

Furthermore, 17, 17, ... are air intake ports located on the side of the motor 5 from the axial flow fan 16 and formed in the peripheral wall of the casing 1 so as to communicate the fan chamber 2 with the outside, and 18, 18, ... are the fan chambers. The orbiting scroll 9 is connected to the axial flow fan 16 so as to communicate the flow fan 2 with the outside.
An exhaust port formed in the peripheral wall of the casing 1 is shown on the side. As the axial fan 16 rotates, external air taken in from the intake port 17 is exhausted to the outside from the exhaust port 18 via the fan chamber 2.

In the scroll compressor configured in this manner, when the motor 5 rotates, the drive shaft 6 also rotates while being supported by the bearing 7 . As a result, the axial flow fan 16 fixed to the rotating shaft 6A also rotates, and the intake port 17,
External air from 17 is sucked into the fan chamber 2,
This air is sent toward the back of the orbiting scroll 9 as shown by the arrow in the figure by the blade 16B, and is sent to the exhaust port 1.
It is exhausted to the outside from 8 and 18.

On the other hand, the rotation of the drive shaft 6 is also transmitted to the orbiting scroll 9 via the crankshaft 6B and the bearing 13.
Here, since the axis of the orbiting scroll 9 and the axis of the fixed scroll 3 are eccentric by a distance δ, and the axis of each shaft of the auxiliary crank 15 is also eccentric by a distance δ, the orbiting scroll 9 is eccentric from the axis of the fixed scroll 3. Performs circular motion relative to. A part of the external air sucked into the fan chamber 2 by the rotation of the axial fan 16 is sucked through the suction port 10, gradually compressed within the compression chamber 11, and then discharged from the discharge port 4. At this time, the radial direction acting on the orbiting scroll 3 by the compressed air in the compression chamber 11,
The pressing force in the axial direction is the bearing 13, the drive shaft 6, and the bearing 7.
, the orbiting scroll 9 is not displaced in the radial and axial directions, and the airtightness of the compression chamber 11 can be ensured.

Thus, compression heat is generated by the compression action in the compression chamber 11, and this compression heat is transmitted to the fixed scroll 3 and the orbiting scroll 9, and is further transmitted to the bearings 7, 13, via the casing 1 and the drive shaft 6. The signal is transmitted to the auxiliary crank 15 and the like. As a result, the scrolls 3 and 9 undergo thermal expansion in the radial and axial directions due to the heat of compression, causing the wrap portions 3B and 9B to come into contact and gouging, or the bearings 7 and 13 and the auxiliary crank 1
The lubricating oil sealed in the 5th grade is about to melt and leak.

However, in the present invention, as described above, external cooling air constantly circulates inside the fan chamber 17 due to the rotation of the axial fan 16, and the back surface of the orbiting scroll 9 and the inside of the casing 1 are exposed to this cooling air. Therefore, deformation of the scrolls 3 and 9 due to thermal expansion, deterioration of the lubricating oil in the bearings 7 and 13, and leakage from the oil seals 8 and 14 can be prevented. Therefore, even when the scroll compressor is of an oil-free type, its life can be extended, and the clearance between the wrap portions 3B and 9B can be narrowed, so that the compression efficiency can be increased.

Furthermore, a suction port 10 is provided in the end plate 9A of the orbiting scroll 9, and the suction port 10 is closed by a filter 12 for preventing dust from entering.
Since the cooling air is sent to the back side of the holder and is pressurized, even if the filter 12 is provided at the suction port 10, it is possible to prevent the compression chamber 11 from becoming a negative pressure, and the air to the suction port side can be prevented from becoming negative pressure. Filter can be installed.

In the embodiment, the casing 1 has been described as having the bottom plate 1A, but the casing 1 is formed into a cylindrical body with openings at both ends, and the bottom plate made of a separate member is fixed to the casing 1 together with the motor 5. It is also possible to have a structure in which the fan chamber 2 is closed off.

The scroll compressor according to the present invention is as described above in detail, and has a fan chamber formed within the casing, and each axial flow fan that takes in external air from an intake port located on the motor side in the fan chamber. Since it is mounted on the drive shaft between the bearings and the exhaust port is located on the orbiting scroll rather than on the axial flow fan, the orbiting scroll and fixed scroll can be constantly cooled, and each scroll can be cooled by thermal expansion. As a result, deformation can be prevented, and accidents such as deterioration or leakage of lubricating oil in each bearing portion due to heat can be prevented. In addition, the bearing between the orbiting scroll and the crankshaft and the bearing between the rotating shaft and the casing receive all the loads acting on the orbiting scroll in the axial and radial directions. Since the orbiting scroll can have a non-contact configuration with respect to the scroll, compression efficiency can be increased even at low compression, and application to an oil-free compressor is facilitated. Moreover, since the axial flow fan can be provided inside the casing, the number of parts is small, and since the motor is attached to the casing, a small scroll compressor directly connected to the motor can be easily manufactured. moreover,
Since the axial fan is used to send air toward the suction port, there are many advantages such as there is no risk of negative pressure in the compression chamber even if a filter is provided at the suction port.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view of a scroll compressor according to the present invention. 1...Casing, 2...Fan chamber, 3...Fixed scroll, 4...Discharge port, 5...Motor, 6
... Drive shaft, 7, 13 ... Bearing, 9 ... Orbiting scroll, 10 ... Suction port, 11 ... Compression chamber, 1
6... Axial flow fan, 17... Intake port, 18... Exhaust port.

Claims (1)

[Scope of utility model registration request] A cylindrical casing having a fan chamber formed therein and having at least one side open; a fixed scroll fixedly provided on the opening side of the casing; a motor attached to the other side of the casing; a drive shaft extending axially into the casing and having a tip end serving as a crankshaft; a first bearing for pivotally supporting the base end of the drive shaft in the casing;
an orbiting scroll arranged in a fan chamber so as to overlap with the fixed scroll to form a compression chamber; a second bearing for pivotally supporting the orbiting scroll on a crankshaft at the tip of the drive shaft; An axial fan located between the first and second bearings and fixed to the drive shaft communicates the fan chamber with the outside so as to send cooling air directly to the back side of the orbiting scroll. an intake port formed in the casing located closer to the motor than the axial fan; and an intake port formed in the casing located closer to the orbiting scroll than the axial fan to communicate the fan chamber with the outside. a suction port provided in the orbiting scroll for sucking the air in the fan chamber into the compression chamber and closed by a filter for preventing dust intrusion; and a suction port for discharging the air compressed in the compression chamber. and a discharge port provided on the fixed scroll.