JP3388558B2 - Oilless scroll vacuum pump - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oilless scroll vacuum pump. 2. Description of the Related Art Conventionally, a technique of vacuuming a container is to put food in a plastic bag, evacuate the air, prevent the adhesion of bacteria floating in the air, and prevent food from spoiling. From ordinary life to low-temperature technologies, such as vacuum cars, blood collection test tubes, and outer walls of thermos bottles or containers that store medical, industrial, or laboratory cooling refrigerants to prevent heat conduction due to convection of air. It is widely used up to. In order to apply a vacuum to the inside of the closed container, a vacuum pump is connected to a suction port of the closed container, and air and other gases are sucked by the vacuum pump. [0002] Recently, an oilless scroll type has attracted attention as a vacuum pump. The scroll action of the oilless scroll vacuum pump is shown in FIG. Referring to FIGS. 2 and 4, the peripheral wall 11 will be described.
Scroll 10 having a first wrap 13 formed in a concave space surrounded by a fixed wrap 10 and a second wrap 21 capable of being fitted to the first wrap 13
By rotating the orbiting scroll 20 around the fixed scroll 10 without rotating, the closed space 2 formed between the two wraps 13 and 21 is formed.
2 is configured to be variable. Therefore, the orbiting scroll 20 is moved with a constant radius around the center of the wrap 2 of the fixed scroll 10 so that the contact point between the two wraps forming the closed space 22 functioning as a compression chamber gradually moves toward the center. The gas taken in from the suction port by the orbital movement is taken into the closed space 22 formed by the two wraps 13 and 21 while wrapping around the winding end end of the second wrap 21, and the orbiting scroll 2
With the revolution of 0, the pressure is increased while moving toward the center while gradually reducing the volume, and the closed space 2
2 is discharged to the outside when it is electrically connected to the discharge port 17. Therefore, in the case of this embodiment, it is extremely important to secure the sealed state of the space 22 formed between the wraps 13 and 21 in order to increase the compression efficiency and the degree of vacuum. Therefore, as shown in FIG. 3, chip seals 31A and 31B made of a self-lubricating resin material are interposed between the facing sliding surfaces on the axial end surface of the wrap. That is, as shown in FIG. 3, an involute-shaped wrap 13 (21) is protruded from the front side of the disc-shaped end plate of the scroll member 10 (20) functioning as a fixed scroll or an orbiting scroll. Lapping groove 13a communicating from the center to the periphery on the end face side
(21a) is recessed, and the tip seal 31 is
A and 31B are connected and fitted. A dust seal 32 is attached to the outer peripheral end surface of the disk-shaped end plate of the scroll member 10 (20) in an annular shape in order to prevent external air from entering the inside. [0004] The oilless scroll type vacuum pump constructed as described above sucks out the gas in the closed vessel and pressurizes and compresses it, so that it is included in the gas together with heat generation. The water vapor is liquefied, and only the compressed gas is discharged from the discharge port, and the remaining moisture is accumulated below the discharge port in the final space formed by the swirling scroll and the fixed scroll. Each time the compressed gas is sent into the final space from the closed space at the preceding stage, the compressed gas collides with the accumulated moisture, and the moisture is applied to the wrapping wall of the rotating scroll and the fixed scroll forming the final space. collide. At that time, an abnormal sound is likely to occur. For this purpose, gas ballast is provided, the atmospheric pressure is introduced into the closed vessel, the partial pressure of water vapor is reduced, and exhaustion is performed without liquefaction. There was a problem. The present invention has been made in view of the above-described drawbacks of the related art, and has as its object to provide a vacuum pump that efficiently drains water. It is another object of the present invention to provide a vacuum pump having a water draining device with a simple configuration and low cost. According to the present invention, a closed space formed between two scrolls is rotated from the suction port provided on the outer peripheral side to the center while rotating the orbiting scroll meshing with the fixed scroll. Oilless exhaust that gradually reduces and moves toward the discharge port provided on the side
In the scroll type vacuum pump, the discharge port is
In the final spot volume on the sliding surface of the fixed scroll
The sliding surface communicates with the atmosphere near the lower side of the discharge port.
Providing a drain hole through which the drain hole is formed.
It is characterized by being inclined downward from the side toward the outside
And According to the present invention, a closed space formed between both scrolls is rotated from the suction port provided on the outer peripheral side to the discharge center provided on the center side while revolving the orbiting scroll meshing with the fixed scroll. In an oilless scroll type vacuum pump which exhausts while gradually reducing and moving toward a port, the discharge port is slid on the fixed scroll.
It is provided in the final spot volume of the moving surface, and the discharge
If a drain hole communicating with the atmosphere is provided near the lower side of the output port,
In both cases, this drain hole is directed outward from the opening side of the sliding surface.
Since it is tilted downward, no water is accumulated below the discharge port, and no abnormal sound is generated by the water. Furthermore, good drainage can be achieved.
Wear. The present invention will be described below in detail with reference to an embodiment shown in the drawings. However, dimensions, materials, shapes, relative positions, and the like of the components described in this embodiment are not merely intended to limit the scope of the present invention, but are merely illustrative examples, unless otherwise specified. Absent. FIG. 1 is a basic configuration diagram according to the present invention. In the figure, the vacuum pump body 1 is connected to a rotating shaft of a motor 5 via a pulley 42 and a belt 34, and drives the orbiting scroll in the vacuum pump body 1 by the rotation of the motor 5, and via a pipe 4. The gas in the closed container 7 is sucked out, and the closed container 7 is evacuated. FIG. 2 shows a scroll type vacuum pump according to an embodiment of the present invention.
As described above, the fixed scroll 10 and the revolving scroll 2
And a frame 40 for supporting these at a predetermined position or pivotably. The fixed scroll 10 is fixed to the end face of the frame 40 and forms a spiral wrap 13 upright in a concave space surrounded by a peripheral wall 11 having a port 16 functioning as a suction port. And a discharge port 17 for discharging the compressed gas at substantially the center thereof.
A drain hole 15 is provided. Swivel scroll 20
Is housed in the recessed space in the frame 40, and the fixed scroll
A spiral wrap 21 having substantially the same shape as the wrap 13 of the screw 10 is formed upright on one surface of an end plate abutting on the peripheral wall 11 and the wraps 13 and 21 are joined together by one.
The fitting is shifted by 80 degrees. Cooling fins 33 and 23 are formed on the back side of the scrolls 10 and 20, respectively, so that the inside of the scrolls can be cooled by air cooling. The wraps 13 and 21 of the scrolls are respectively provided in the grooves formed in the end surfaces thereof in contact with the scrolls on the other side, and the self-lubricating seals composed of the tip seals 31A and 31B described with reference to FIG. And a ring-shaped self-lubricating sealing member 32 is fitted into a groove recessed in an end surface of the turning scroll 20 which comes into contact with the end plate. The airtightness with the outside in the concave space 12 is maintained. On the other hand, the frame 40 supports a main drive crankshaft 41 having a pulley 42 attached to one end thereof along a center axis, and the main drive crankshaft 41
The driven crankshaft is supported at positions deviated from each other by 120 degrees (three places). Each of these crankshafts 41 and 43 has a revolving scroll 2
The rotating scroll 20 is prevented from rotating by the driving rotation of the main driving crankshaft 41, and the fixed scroll 10 is fixed at a constant radius. Is configured to be able to revolve around the center of the lap. The suction port 16 has a pipe 4
Are connected to each other, and the tip is connected to the sealed container 7 shown in FIG. FIG. 6 is a view showing a relationship between a fixed scroll and a drain hole of the vacuum pump according to the first embodiment of the present invention. In the figure, a discharge port 17 is provided at the center of the fixed scroll 10, and a wrap 13 stands up from the sliding surface 14 in a spiral shape so as to surround the discharge port 17 from below. The drain hole 15 is provided below the discharge port 17 in such a manner that its opening diameter is in contact with the inner wall of the wrap 13 and is inclined downward from the opening of the sliding surface 14 toward the outside as shown in FIG. Have been. FIG.
FIG. 7 is a view showing the operation of the scroll by using a fixed scroll provided with, and viewed from the back side of FIG. 6. Next, the operation of this embodiment will be described with reference to FIGS.
This will be described with reference to FIG. In FIG. 1, when the power supply of a vacuum pump 1 (not shown) is turned on, the turning scroll 20 starts to be driven. Now, the gas in the space a in FIG. 4A is driven by the wrap 21 of the orbiting scroll 20 so that the gas b in FIG.
Then, as shown in (A) and (B) alternately below, they are taken into the closed spaces indicated by c, d, e, f, and g and compressed, and finally the discharge port 17 is opened. The compressed gas is discharged to the outside from the discharge port 17 after reaching the space h. On the other hand, the gas taken in from the closed container is
Water droplets are liquefied by being compressed. Therefore, the water generated from the compressed gas is accumulated on the wrap 13 below the discharge port 17 as shown by the oblique line in FIG. 6 unless the drainage treatment is performed. However, since the drainage hole 15 is provided as shown in the figure. Are discharged along the slope. As described above, the water is discharged to the outside of the vacuum pump 1 through the drain hole 15 opened below the final space i, and no abnormal noise as a water hammer is generated. FIG. 7 is a diagram showing a relationship between another fixed scroll and a drain hole. This embodiment has an opening center offset from the center of the fixed scroll 10 by approximately 40 degrees to the lower left as a discharge port in which a hole for discharging compressed gas and a drain hole are integrated. And a discharge port 24 having an opening in contact with the outer diameter of the opening. As shown in FIG. 8, the discharge port 24 is provided to be inclined downward from the sliding surface 14 to the outside. Accordingly, the water generated from the compressed gas is discharged from the discharge port 24 along with the discharge of the compressed gas along with the inclination thereof. Next, the operation of another embodiment will be described with reference to FIG. FIG. 5 is a diagram viewed from the back surface of FIG. Now, the gas in the space a in FIG. 5A is taken into b in FIG. 5B by driving the wrap 21 of the orbiting scroll 20, and as shown in FIGS. 5A and 5B alternately. Then, the compressed gas is taken into the closed spaces indicated by c, d, e, f, and g and compressed, and finally reaches the space h where the discharge port 24 is opened, and the compressed gas is discharged from the discharge port 24 to the outside. Things. On the other hand, the gas taken in from the closed container liquefies the water droplets, and is discharged together with the compressed gas to the outside of the vacuum pump by the discharge port 24 opened below the final space i. Discharge port 24
Is inclined downhill toward the outside, so that moisture is discharged along the slope. According to the present invention, since a drain hole is provided below the discharge port as described above, or a hole which serves both as the compressed gas discharge and the water drain hole is provided deviated downward from the center of the fixed scroll, so that the compression Does not emit abnormal noise due to moisture generated from gas. [0016] As described, according to above, in the present invention, draining
Since the holes discharge the moisture generated from the compressed gas,
It is possible to provide an oil-less scroll type vacuum pump that does not generate abnormal noise and has high durability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a basic configuration diagram of the present invention. FIG. 2 is a diagram showing one embodiment of a scroll type vacuum pump according to the present invention. FIG. 3 is a perspective view showing a scroll member and a sealing element. FIG. 4 is a schematic view showing the operation of a scroll. FIG. 5 is a schematic view showing another scroll operation. FIG. 6 is a diagram showing a relationship between a fixed scroll and a drain hole. FIG. 7 is a diagram showing a relationship between another fixed scroll and a drain hole. FIG. 8 is a view showing a cross section of the fixed scroll shown in FIG. 7; [Description of Signs] 1 Oilless scroll type vacuum pump main body 4 Piping 5 Motor 7 Closed vessel 10 Fixed scroll 15 Drain hole 16 Suction port 17 Discharge port 20 Swivel scroll 24 Discharge port 31 Self-lubricating seal member 32 dust seal

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F04C 25/02 F04C 18/02

Claims (1)

(57) [Claims] 1. A revolving gear that meshes with a fixed scroll.
Formed between both scrolls while revolving the scroll
To the center from the suction port provided on the outer peripheral side
Do not gradually reduce and move toward the discharge port provided on the
Oilless scroll type vacuum pump that exhausts air
AndConnect the discharge port to the final slide on the sliding surface of the fixed scroll.
Provided in the pot volume, below the discharge port on the sliding surface
A drain hole communicating with the atmosphere is provided near the side, The drain hole is downward from the opening side of the sliding surface to the outside.
Be tilted toward Oilless disk characterized by
Roll type vacuum pump.