JP3353979B2 - Scroll air compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type air compressor suitable for use in, for example, compressing air and storing the compressed air in an air tank. The present invention relates to a scroll type air compressor.

[0002]

2. Description of the Related Art Generally, a compressor has a compressor body and an air tank for storing compressed air discharged from the compressor body. The compressor body has a casing, a base end projecting out of the casing, and a tip end having a casing. A drive shaft extending into the casing and serving as a crank, a orbiting scroll positioned in the casing and rotatably mounted on the crank of the drive shaft and provided with a spiral wrap portion; And a fixed scroll provided with a spiral wrap portion overlapping the wrap portion of the orbiting scroll, and formed between the wrap portion of the fixed scroll and the wrap portion of the orbiting scroll. A compression chamber that discharges air from the discharge port while compressing air sucked from the port,
A scroll type air compressor including a suction filter connected to the suction port is known.

[0003] A discharge port of the compressor body is connected to an air tank through a pipe, and a pressure-holding valve is provided in the middle of the pipe or in a joint or the like connecting the air tank to a tip end of the pipe. The compressed air discharged from the discharge port is allowed to flow toward the tank, and the compressed air is prevented from flowing in the opposite direction.

In the scroll type air compressor according to the prior art, the orbiting scroll is turned by rotating the drive shaft from the outside with an electric motor or the like, and external air is sucked from a suction port, and the air is drawn into the compression chamber. The compressed air is discharged from the discharge port while being compressed, and the compressed air is stored in an air tank.

[0005]

According to the above-mentioned prior art, when external air is sucked into the compressor body during the compression operation, dust in the air is suctioned by a suction filter provided at a suction port of the compressor body. And so on.

For this reason, while the compression operation is continued, dusts and the like adhere to the suction filter and gradually accumulate therein.
The suction filter may be clogged. Then, when the suction filter is clogged, the flow of air to the suction port is interrupted, and the compression efficiency of the air is reduced, resulting in a problem that the performance is reduced early.

The present invention has been made in view of the above-mentioned problems of the prior art. The present invention provides a scroll-type air compressor which can prevent clogging of a suction filter and can maintain compression performance for a long period of time. It is intended to be.

[0008]

In order to solve the above-mentioned problems, a feature of the configuration adopted by the present invention is that a discharge passage connecting between a discharge port of a compressor body and an air tank has the above-mentioned structure. A check valve that allows the compressed air of the machine body to flow from the discharge port to the air tank and prevents the air from flowing in the reverse direction, and is provided to bypass the check valve and is provided from the air tank to the compressor body. There is provided a flow rate regulating means for regulating the flow rate when the compressed air flows backward, and a switching valve for selectively switching between the check valve and the flow rate regulating means.

[0009]

According to the above configuration, during the compression operation, the external air sucked from the suction port through the suction filter is compressed in the compression chamber and discharged from the discharge port. At this time, the switching valve is switched so that the compressed air discharged from the discharge port flows through the check valve to the discharge passage toward the air tank, and the compressed air discharged from the discharge port is supplied to the air tank.

On the other hand, when the compression operation is stopped,
If the switching valve is switched so that a part of the compressed air stored in the air tank flows back to the compressor body by bypassing the check valve, the compressed air is discharged to the discharge port of the compressor body. Flows through the compression chamber toward the suction port while rotating the orbiting scroll in the reverse direction, and is discharged from the suction port to the outside via the suction filter. The compressed air flows in the suction filter in a direction opposite to that in the compression operation, so that dust and the like attached to the suction filter can be discharged.

When the compressed air flows backward from the air tank toward the compressor body, a flow rate regulating means provided in the discharge passage regulates the flow rate of the compressed air discharged from the air tank. This prevents high-pressure compressed air from entering the compression chamber of the compressor main body from the air tank and reversely rotating the orbiting scroll at high speed.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

First, FIGS. 1 to 4 show a first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a package formed in a substantially rectangular box shape, and the package 1 is formed by joining panels made of a thin metal plate by means such as spot welding.

Reference numeral 2 denotes a compressor main body provided at an intermediate position in the vertical direction in the package 1. The compressor main body 2 includes a casing 3, a drive shaft 4, an orbiting scroll 5, a fixed scroll 6, and a suction filter 10 to be described later. And so on.

Reference numeral 3 denotes a casing constituting the outer shape of the compressor main body 2, and the casing is formed in a stepped cylindrical shape from a large diameter portion 3A on one side and a small diameter portion 3B on the other side.

Reference numeral 4 denotes a drive shaft rotatably supported in a small diameter portion 3B of the casing 3 via a bearing (not shown). The drive shaft 4 has a base end extending from one end of the casing 3 to the outside. A small-diameter pulley 24 to be described later is attached, and the distal end side extends into the large-diameter portion 3A of the casing 3, and the distal end portion is a crank 4A which is eccentric with a predetermined dimension.

Reference numeral 5 denotes an orbiting scroll whose one end is rotatably mounted on a crank 4A of the drive shaft 4. The orbiting scroll 5 includes a disk-shaped end plate 5A and a head plate 5A.
A spiral wrap portion 5 erected on the other side surface of the end plate 5A, the center side of the end plate 5A being the winding start end, and the outer peripheral side being the end end of winding.
B.

Reference numeral 6 denotes a fixed scroll provided opposite to the orbiting scroll 5 and attached to the other end of the large-diameter portion 3A of the casing 3. The fixed scroll 6 includes a disk-shaped end plate 6A and one end plate 6A. A spiral wrap portion 6B is provided upright on the side surface, and the center side of the end plate 6A is a winding start end, and the outer peripheral side is a winding end end.

Here, the fixed scroll 6 and the orbiting scroll 5 are disposed such that their respective wrap portions 6B, 5B overlap with each other, and a plurality of compression chambers 7, 7,, are provided between the respective wrap portions 6B, 5B. ... are formed.

A suction port 8 is formed on the outer peripheral side of the fixed scroll 6, and a suction port communicating with the outermost compression chamber 7 among the compression chambers 7, and a suction port 9 is formed at the center of the fixed scroll 6 and has the most central compression. In the compression operation, external air is sucked from the suction port 8 into the compression chamber 7 on the outermost peripheral side through a suction filter 10 described later, and compressed in each compression chamber 7. After that, the compressed air in the most central compression chamber 7 is discharged from the discharge port 9 to the air tank 17 via a discharge pipe 11 and the like described later.

Reference numeral 10 denotes a suction filter attached to the suction port 8 from the outside of the casing 3. The suction filter 10 is scattered in the air when suctioning external air into the compression chamber 7 during the compression operation. Dust and the like are attached to a filter (not shown) provided therein and removed.

Reference numeral 11 denotes a discharge pipe which forms a discharge passage connecting the discharge port 9 of the compressor body 2 and the air tank 17,
Reference numeral 12 denotes a pressure-holding valve as a check valve provided in the middle of the discharge pipe 11. The pressure-holding valve 12 allows compressed air to flow from the discharge port 9 of the compressor body 2 to the air tank 17. This prevents the compressed air in the air tank 17 from flowing backward through the discharge pipe 11 and leaking when the compression operation is stopped.

Reference numeral 13 denotes a bypass pipe provided so as to bypass the pressure holding valve 12, and one end of the bypass pipe 13 is disposed between the pressure holding valve 12 and the discharge port 9 of the compressor body 2. The other end is connected to a solenoid valve 15 described later, and is selectively connected to the air tank 17 by the solenoid valve 15.

Reference numeral 14 denotes a throttle valve provided as a flow rate regulating means provided in the middle of the bypass pipe 13. The throttle valve 14 is compressed from the air tank 17 when the solenoid valve 15 is switched to the exhaust position (b). The flow rate of the compressed air is reduced by restricting the compressed air exhausted toward the machine body 2 in the direction indicated by the arrow in FIG.

Reference numeral 15 denotes a solenoid valve as a switching valve provided between the pressure holding valve 12 and the throttle valve 14 and the air tank 17, and the solenoid valve 15 is constituted by a spring offset type 3-port 2-position solenoid valve or the like. The solenoid valve 15 is connected to a control unit 16 described later.
And is selectively switched to the supply position (a) or the exhaust position (b) by power supply (control signal) from the control unit 16.

That is, when there is no power supply from the control unit 16, the solenoid valve 15 is switched to the supply position (a) as shown in FIG. 2, and the discharge port 9 of the compressor body 2 is connected via the pressure holding valve 12. It is connected to the air tank 17. As a result, the compressed air discharged from the discharge port 9 of the compressor body 2 flows through the discharge pipe 11 to the air tank 17 via the pressure holding valve 12 in the direction indicated by the arrow in FIG.

On the other hand, when power is supplied from the control unit 16, the solenoid valve 15 is switched to the exhaust position (b) as shown in FIG.
Is connected to the air tank 17 via the throttle valve 14. As a result, a part of the compressed air in the air tank 17 flows in the direction of the arrow in FIG. 3 toward the compressor body 2 via the bypass pipe 13 and the like, and flows in from the discharge port 9 of the compressor body 2. Then, the air passes through each compression chamber 7 and is exhausted from the suction port 8 to the outside through the suction filter 10. As described above, when the solenoid valve 15 is switched to the exhaust position (b) and the compressed air flows back through the compressor body 2, the compression operation is stopped.

Reference numeral 16 denotes a control unit constituted by a microcomputer or the like. An input side of the control unit 16 is connected to a pressure sensor 20 provided in an air tank 17 described later, and an output side is connected to the solenoid valve 15. It is connected. The control unit 16 controls the solenoid valve 15 and the like based on a detection signal of a pressure sensor 20 provided in an air tank 17 described later.

Reference numeral 17 denotes an air tank provided in the package 1 at a position below the compressor main body 2. The air tank 17 is fixed to a bottom plate of the package 1 via a fixing table 18, Is provided with a mounting table 19 for mounting the compressor body 2. The air tank 17
Is connected to a discharge port 9 of the compressor body 2 via a discharge pipe 11 and the like, and stores compressed air discharged from the discharge port 9 during a compression operation.

Reference numeral 20 denotes a pressure sensor provided in the air tank 17, which detects the pressure in the air tank 17 and outputs a detection signal to the control unit 16. That is, as shown in FIG. 4, when the pressure in the air tank 17 increases and exceeds a predetermined upper limit pressure P1 (at time t1), the pressure in the air tank 17 decreases and the predetermined lower limit pressure P2 is reduced. When it falls below (at time t2), a detection signal is output to the control unit 16.

Reference numeral 21 denotes a drive motor located in the package 1 and mounted on the upper side of the compressor main body 2 via a mount 22. The drive motor 21 has an output shaft 21A which is supplied with power from the outside. Is driven to rotate. The power supply to the drive motor 21 is controlled by an instruction from the control unit 16. That is, the output side of the control unit 16 is the drive motor 2
The control unit 16 outputs a signal to the power supply for the drive motor 21 based on the detection signal of the pressure sensor 20, whereby the drive motor 21 is connected to the power supply for the drive motor 21. Driving and stopping are controlled.

Reference numeral 23 denotes a large-diameter pulley fixed to the tip of the output shaft 21A of the drive motor 21, and 24 denotes a small-diameter pulley fixed to one end of the drive shaft 4 of the compressor body 2, respectively. The output shaft 21 of the drive motor 21 is connected to the diameter pulley 23 by a belt 25.
The rotation drive of A is transmitted to the drive shaft 4.

The scroll type air compressor according to the present embodiment has the above-described configuration. Next, the operation thereof will be described with reference to FIG.

First, when the compression operation is started, the drive motor 21 is driven, and the rotation of the output shaft 21A is transmitted to the drive shaft 4 via the belt 25 or the like.
Performs a turning motion with a turning radius of a predetermined size. The compression chambers 7, 7,... Defined between the wrap portions 5B, 6B by this swirling motion are continuously reduced, and the suction ports 8 are formed.
The compressed air is discharged from the discharge port 9 while the external air sucked through the suction filter 10 is sequentially compressed in the compression chambers 7.

At this time, no control signal is supplied from the control unit 16 to the solenoid valve 15, and the solenoid valve 15 is in the supply position (a) as shown in FIG. Is connected to the air tank 17 via the discharge pipe 11 and the pressure holding valve 12, so that the compressed air discharged from the discharge port 9 is directed toward the air tank 17 via the discharge pipe 11 and the pressure holding valve 12. 2
It flows in the direction indicated by the arrow in the middle and is supplied to the air tank 17.

However, when the compressed air continues to be supplied to the air tank 17 by the above-described compression operation and the pressure in the air tank 17 exceeds the upper limit pressure P1 (at time t1 in FIG. 4), the pressure sensor 20 Detects this and outputs a detection signal to the control unit 16. And
The control unit 16 determines, based on this detection signal,
A signal is output to stop the drive motor 21 to stop the compression operation, and immediately thereafter, power is supplied to the solenoid valve 15.
As a result, the solenoid valve 15 is automatically switched from the supply position (a) to the exhaust position (b), and the discharge port 9 of the compressor body 2 and the air tank 17 are connected via the bypass pipe 13 and the throttle valve 14. Will be done.

As a result, a part of the compressed air in the air tank 17 flows back to the compressor body 2 through the bypass pipe 13 and the throttle valve 14, and the compressed air flows from the discharge port 9 into the compression chamber 7. Inflow. Then, the compressed air flows while rotating the orbiting scroll 5 in the reverse direction from the center compression chamber 7 of the compression chambers 7 to the outermost compression chamber 7, and flows from the suction port 8 through the suction filter 10. Exhaust to the outside. In this manner, by passing air through the suction filter 10 in a direction opposite to that in the compression operation, dust or the like attached to the suction filter 10 can be discharged to the outside.

At this time, by providing the throttle valve 14, the flow rate of the compressed air flowing from the air tank 17 toward the compressor body 2 is regulated. That is, the compressed air in the air tank 17 has a very high pressure, and when this compressed air flows directly into each compression chamber 7 through the discharge port 9 of the compressor body 2, the orbiting scroll 5 rapidly reversely rotates. However, since there is a possibility that the orbiting scroll 5 may be damaged, the throttle valve 14 prevents the orbiting scroll 5 from rapidly reversely rotating, and has a flow rate suitable for discharging dust or the like attached to the suction filter 10. It has been adjusted to be.

Further, after a lapse of a predetermined time T from the time point t1 in FIG. 4 (time point t2), the control unit 16 stops supplying power to the solenoid valve 15, and the solenoid valve 15 returns to the supply position ( Switch to a). Thereby, the backflow of the compressed air from the air tank 17 to the compressor body 2 is automatically stopped. Note that t in FIG.
The predetermined time T from 1 to t2 is an optimal exhaust time for discharging the dust adhering to the suction filter 10, and is stored in the control unit 16 in advance.

Next, at time t3 in FIG. 4, that is, when the compressed air in the air tank 17 is used and decreases and falls below the lower limit pressure P2, the detection signal of the pressure sensor 20 is sent to the control unit 16. The control unit 16 instructs to drive the drive motor 21 based on the output. Thus, the compression operation is started again, and the compressed air is supplied to the air tank 17.

Thus, in the present embodiment, in the middle of the discharge pipe 11, the bypass pipe 13 that bypasses the pressure holding valve 12 is arranged.
An air tank 17 is provided in the middle of the bypass pipe 13.
A throttle valve 14 for regulating the flow rate of the compressed air flowing backward from the compressor toward the compressor body 2 is connected, and between the pressure holding valve 12 and the throttle valve 14 and the air tank 17, a pressure holding valve 12 side and a throttle valve are connected. Solenoid valve 15 for selectively switching between 14 side
During the compression operation, the solenoid valve 15 is switched to the supply position (a) by the control signal of the control unit 16 so that the discharge port 9 of the compressor body 2 is connected to the discharge pipe 11 as shown in FIG. , Connected to the air tank 17 through the pressure holding valve 12 and the compressor body 2
Compressed air discharged from the discharge port 9 of the air tank 1
7 can be supplied.

On the other hand, when the compression operation is stopped, the solenoid valve 15 is switched to the exhaust position (b) by the control signal of the control unit 16 at a predetermined time (t1) shown in FIG. The discharge port 9 of the compressor main body 2 is connected to the air tank 17 via the bypass pipe 13 and the throttle valve 14, and a part of the compressed air in the air tank 17 flows back toward the compressor main body 2.
Can be exhausted through the suction filter 10. Thus, dust and the like adhering to the suction filter 10 can be effectively removed.

Therefore, it is possible to reliably prevent the suction filter 10 from being clogged, and to set the suction port 8 in the compression operation.
It can be reliably prevented that the flow of air is blocked and the compression efficiency of air is reduced.

Further, by providing the throttle valve 14, the flow velocity of the compressed air flowing backward from the air tank 17 toward the compressor body 2 can be regulated, and the high-pressure compressed air
To prevent the orbiting scroll 5 from rotating in the compression chamber 7 of the compressor body 2 at high speed and reversely rotating at high speed, and to reliably prevent the orbiting scroll 5 from being damaged.

Further, the control unit 16 and the pressure sensor 20 and the like allow the air tank 1 during the compression operation.
When the pressure in the chamber 7 exceeds the upper limit pressure P1 (at time t1), the compression operation is stopped, the solenoid valve 15 is switched to the exhaust position (b), and the dust of the suction filter 10 is removed. 10 can be automatically removed at appropriate time intervals, so that the maintenance such as maintenance of the suction filter 10 can be eliminated, and the compression performance of the scroll air compressor can be maintained for a long time. it can.

FIGS. 5 and 6 show a second embodiment of the present invention.
The feature of this embodiment is that the switching valve is switched by operating a manual switch from the outside, the compressed air in the air tank is caused to flow backward to the compressor body, and the dust of the suction filter is removed. It is in. In this embodiment, the same components as those of the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals, and the description thereof will be omitted.

In the figure, reference numeral 31 denotes a manual switch connected to the input side of the control unit 16. The manual switch 31 is mounted on, for example, the side surface of the package 1 so that an operator can operate it from outside. I have.

As shown in FIG. 6, when the operator turns on the manual switch 31 during the compression operation (at time t1 '), an interrupt signal is output to the control unit 16, and based on this, the control unit 16 Instructs to stop the drive motor 21 to stop the compression operation,
Immediately thereafter, power is supplied to the solenoid valve 15. As a result, the solenoid valve 15 is automatically switched from the supply position (a) to the exhaust position (b), and the discharge port 9 of the compressor body 2 and the air tank 17 are connected via the bypass pipe 13 and the throttle valve 14. Be connected. As a result, a part of the compressed air in the air tank 17 flows back toward the compressor main body 2, and dust and the like attached to the suction filter 10 are discharged to the outside.

Further, after a lapse of a predetermined time T from the time point t1 'in FIG. 6 (time point t2'), the control unit 16 stops supplying power to the solenoid valve 15, and the solenoid valve 15 is switched to the supply position. Switching to (a). Thereby, the backflow of the compressed air from the air tank 17 to the compressor body 2 is automatically stopped. Immediately after this, the control unit 16 instructs to drive the drive motor 21 and restarts the compression operation.

Thus, according to the present embodiment, even during the compression operation, the operator can arbitrarily operate the manual switch 31 to temporarily stop the compression operation and automatically remove the dust from the filter 10. it can. Thus, for example, when the worker notices that dust or the like is clogged in the suction filter 10 during the compression operation and the compression efficiency is reduced, the operator turns on the manual switch 31 so that the suction filter 10 is clogged. Dust and the like can be automatically removed.

Therefore, it is not necessary to completely stop the compression operation in order to remove the dust from the suction filter 10, so that the maintainability, work efficiency and the like of the suction filter 10 can be greatly improved.

In the above embodiment, the suction filter 10
When the solenoid valve 15 is switched to the exhaust position (b) in order to discharge dust and the like adhering to the compressor, the compressed air in the air tank 17 flows through each of the compression chambers 7 in the compressor body 2. The present invention is not limited to this. As shown in FIG. 7, when the solenoid valve 15 is switched to the exhaust position (b), the compressed air in the air tank 17 flows directly back to the suction filter 10. A circuit configuration may be used.

In each of the above embodiments, the bypass pipe 1
Although the throttle valve 14 is provided as a flow rate regulating means in the middle of 3, the flow rate regulating means may be integrally incorporated as a throttle valve 14 'in the solenoid valve 15 as shown in FIG.

Further, in each of the above embodiments, the package 1
Inside the compressor body 2, air tank 17 and drive motor 2
Although a so-called package-type scroll-type air compressor accommodating 1 and the like has been described as an example, the present invention is not limited to this. Furthermore, the present invention can be applied to a scroll-type air compressor in which a drive motor is integrally accommodated in a casing 3 of the compressor body 2.

[0056]

As described above in detail, according to the present invention, the discharge passage connecting the discharge port of the compressor body and the air tank bypasses the check valve provided in the middle of the discharge passage. And a switching valve for selectively switching between the check valve and the flow rate regulating means is provided, so that when the compression operation is stopped, the switching valve is switched to the flow rate regulating means side, so that air The tank can be connected to the compressor main body through the flow rate regulating means, and the compressed air in the air tank can flow back toward the compressor main body through the flow rate regulating means.

Thus, air in the opposite direction to that during the compression operation can be circulated through the suction filter, and dust and the like adhering to the suction filter can be effectively discharged. Therefore, it is possible to reliably prevent the suction filter from being clogged,
The compression performance of the scroll air compressor can be maintained for a long period of time.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a state in which a scroll type air compressor according to a first embodiment of the present invention is accommodated in a package.

FIG. 2 is a circuit diagram showing a state during a compression operation of the scroll air compressor of FIG.

FIG. 3 is a circuit diagram showing a state in which dust is removed from a suction filter.

FIG. 4 is a time chart showing an operation state of the scroll compressor.

FIG. 5 is a circuit diagram showing a state during a compression operation of a scroll compressor according to a second embodiment of the present invention.

FIG. 6 is a time chart showing an operation state of the scroll compressor.

FIG. 7 is a circuit diagram showing a modified example of the scroll air compressor according to the first embodiment.

[Explanation of symbols]

 Reference Signs List 2 compressor body 3 casing 4 drive shaft 4A crank 5 orbiting scroll 5B, 6B lap portion 6 fixed scroll 7 compression chamber 10 suction filter 11 discharge pipe 12 pressure holding valve (check valve) 14 throttle valve (flow rate regulating means) 15 solenoid valve (Switching valve) 17 Air tank

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-172070 (JP, A) JP-A-5-71472 (JP, A) JP-A-62-149321 (JP, A) JP-A-60-1985 78617 (JP, A) JP-A-4-265481 (JP, A) JP-A-5-113186 (JP, A) JP-A-4-352285 (JP, A) JP-A-1-315308 (JP, A) Japanese Utility Model Application No. 3-122290 (JP, U) Japanese Utility Model Application No. 44-2019 (JP, Y1) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04C 18/02 311 F04B 39/16 F04C 29 / 00

Claims (1)

(57) [Claims] 1. A compressor comprising: a compressor main body; and an air tank for storing compressed air discharged from the compressor main body. The compressor main body includes a casing, a base end protruding outside the casing, and a distal end inside the casing. A orbiting scroll that is extended into a crank, a orbiting scroll that is located inside the casing and is pivotally attached to the crank of the driving shaft, and is provided with a spiral wrap portion, and is opposed to the orbiting scroll. A fixed scroll provided and provided with a spiral wrap portion overlapping the wrap portion of the orbiting scroll, and air sucked from a suction port formed between the wrap portion of the fixed scroll and the wrap portion of the orbiting scroll. In a scroll-type air compressor including a compression chamber that discharges from a discharge port while compressing, and a suction filter connected to the suction port, A discharge passage connecting the discharge port of the compressor body and the air tank has a reverse passage that allows the compressed air of the compressor body to flow from the discharge port to the air tank and prevents the compressed air from flowing in the opposite direction. A stop valve, a flow rate regulating means provided to bypass the check valve and regulates a flow rate when compressed air flows backward from the air tank toward the compressor body, and the check valve and the flow rate regulating means. A scroll type air compressor comprising a switching valve for selectively switching.