JP2506801Y2 - Oil rotary vacuum pump - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil rotary pump used in various vacuum equipment fields.

[0002]

2. Description of the Related Art A conventional oil rotary pump is shown in FIGS. The oil rotary pump mainly includes a pump mechanism P, a motor 20, and a coupling chamber C.

The pump mechanism P comprises a pump body 10, a pump case 11, and a pump shaft 13 projecting toward a motor from a pump front wall 12 which is a front portion of the pump body 10. In the pump case 11, the pump body 1
Oil is added to lubricate and cool 0.

The coupling chamber C between the pump mechanism P and the motor 20 has a box-shaped structure in which the left and right side surfaces are open. Inside the coupling chamber C, the motor shaft 21 of the motor 20 and the pump shaft 13 and 13 are connected by a coupling 30. An axial fan 40 for air-cooling the pump mechanism P is attached to an exposed portion of the pump shaft 13 between the coupling 30 and the pump front wall 12, so that the pump shaft 13 rotates in conjunction with the rotation of the pump shaft 13. It has become.

Since the motor shaft 21 and the axial flow fan 40 rotate in the coupling chamber C, the left and right side plates 32 are attached to the left and right side surfaces as safety covers to prevent people from being caught in them. The left and right side plates 32 are provided with slit holes 33 for sending air to the axial fan 40, and the air that has flowed in from this is the axial fan 4.
After being directed to the pump front wall 12 by 0, it is discharged from the clearance between the side plate 32 and the pump front side surface 14, and along the cooling fins having the uneven shape provided on the pump front side surface 14 and the outer surface of the pump case 11. Flowing.

[0006]

In the conventional oil rotary pump described above, the slit hole 33 for sending air to the axial fan 40 has not been devised so far, but only a plurality of slit-shaped holes are provided at the upper end of the side plate. From the bottom to the bottom.

That is, in both the left and right side plates 32, 5 to 20 horizontal slit holes 33 are formed at equal intervals from the upper end to the lower end of the side plate.

However, in this configuration, not all of the air taken in from the slits 33 is made to flow backward by the axial fan 40, but some of the taken air is again discharged from the slits 33 by the axial fan 40. Was done. This point will be described in detail below.

The axial fan 40 rotates around the pump shaft 13. At this time, relative to the pump shaft height, the relative movement direction of the blades of the axial flow fan 40 with respect to the side plate 32 is reversed on the upper side and the lower side. For example, when the blade rotates above the pump shaft height in a direction approaching the side plate 32, when the blade reaches the pump shaft height in due course, the blade rotates below the pump shaft height away from the side plate 32. While the blade moves toward the side plate 32, a part of the air taken into the coupling chamber is conversely discharged by the blade from the slit hole.

Therefore, the air taken in from the slit hole 33 cannot be efficiently sent to the pump side, which deteriorates the cooling efficiency of the pump. If the pump is not sufficiently cooled, the oil temperature in the pump case 11 becomes high, causing poor lubrication or an increase in vapor pressure, which causes a problem that the performance as a vacuum pump deteriorates.

An object of the present invention is to eliminate such drawbacks and efficiently cool the pump by air.

[0012]

The present invention, which has been made to solve the above problems, provides a pump mechanism, a motor, and a coupling chamber for connecting the pump shaft of the pump mechanism and the motor shaft of the motor. In the oil rotary pump that air-cools the pump mechanism by the axial fan provided in the coupling chamber, one of the left and right case side plates of the coupling chamber has a slit hole for taking air into the axial fan. A slit for air intake to the axial fan is provided from near the height of the pump shaft to near the lower end, and by providing this slit hole on the other case side plate from near the height of the pump shaft to near the upper end. The feature is that the holes are asymmetrical.

[0013]

In the oil rotary pump of the present invention, the slit holes provided in the side plate are not provided uniformly from the upper end to the lower end of the side plate, but slit holes are provided in consideration of the air flow due to the rotational movement of the axial fan. There is.

That is, since the relative movement direction of the blades of the axial fan with respect to the side plate is reversed on the upper side and the lower side of the pump shaft height as a reference, the moving direction of the blade approaches the side plate. Do not provide slit holes in the side plate on either the upper side or the lower side. Then, on the side opposite to the above in which the moving direction of the blades is the direction away from the side plate, slit holes are provided as in the conventional case.

Then, the air at the moment when it is taken in from the slit hole is not discharged again from the slit hole because the blade is rotating in the direction away from the side plate, that is, the direction in which the air is drawn. At the position where the blade advances toward the side plate as the rotation progresses, there is no slit hole, so that the air is not discharged to the outside. As described above, the air once entering the coupling chamber through the slit hole is not released again from the slit hole, and efficient air cooling can be performed.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of an oil rotary pump according to an embodiment of the present invention. 3 is a front view of the conventional oil rotary pump, the oil rotary pump according to the present invention is also the front view of the oil rotary pump according to the present invention since the parts shown in FIG. 3 are not different. Also,
4 (a) is a sectional view taken along the line AA 'in FIG. 3, that is, a sectional view at the position of the axial fan, FIG. 4 (b) is a left side plate as viewed in b, and FIG. Shows the right side plate of.

This oil rotary pump mainly includes a pump mechanism P.
And a motor 20 and a coupling chamber C.

The pump mechanism comprises a pump body 10, a pump case 11, and a pump shaft 13 projecting from the pump front wall 12 which is the front surface of the pump body 10 toward the motor. In the pump case 11, the pump body 10
Contains oil to lubricate and cool the.

The coupling chamber C between the pump mechanism P and the motor 20 has a box-shaped structure in which the left and right side surfaces are open. In this coupling chamber C, the motor shaft 21 of the motor 20 and the pump shaft 13 and 13 are connected by a coupling 30. An axial fan 40 for air-cooling the pump mechanism P is attached to an exposed portion of the pump shaft 13 between the coupling 30 and the pump front wall 12, so that the pump shaft 13 rotates in conjunction with the rotation of the pump shaft 13. It has become.

Since the motor shaft 21 and the axial fan 40 rotate in the coupling chamber C, the left and right side plates 3 serve as safety covers on the left and right side surfaces to prevent people from being caught in them.
2a and 32b are attached. The left and right side plates 32
Slit holes 33a and 33b are provided in a and 32b according to the rotation direction of the axial fan 40. That is, as shown in FIG. 4, when the axial fan 40 rotates to the left, a slit 33a is provided in the left side plate 32a from near the pump shaft height to the lower end, and in the right side plate 32b, a slit 33a is formed from the pump shaft height to the upper end. A slit 33b is provided over the area.

Next, the operation of this configuration will be described.

As shown in FIG. 4, the rotation range of the axial fan 40 is divided into four by 90 degrees.
In the B, C, and D quadrants, when the axial fan 40 rotates, air flows in through the slit holes 33a in the B quadrant. In the B quadrant, the blades of the axial fan 40 move in a direction away from the left side plate 32a, that is, in a direction of sucking in air that has flowed in from the slit 33a. There is no.
Next, in the C quadrant, the blade of the axial fan 40 is the right side plate 32b.
Exercise in the direction toward. At this time, a part of the air is fanned by the blades and tries to move toward the right side plate 32b.
Since there is no slit hole in the quadrant, it is not released to the outside. Subsequently, in the D quadrant, air is sucked from the slit hole 33b by the same action as in the B quadrant, and in A quadrant, the inflowing air is prevented from being released to the outside by the same action as in the C quadrant. By continuing the same rotation thereafter, the taken-in air is sent backward without re-ejecting the air to the outside.

[0024]

As described above in detail, according to the present invention, the slit hole provided in the side plate is arranged in consideration of the rotation direction of the axial fan, so that the air taken in from this slit hole is prevented. It will not be released again from the slit hole to the outside. As a result, the air can be efficiently sent toward the pump mechanism, and the cooling performance is significantly improved.

Cooling performance As a result of measuring the temperature of the rear surface of the pump case, a temperature difference of several degrees was measured as compared with the conventional device of FIG. 2 and the effect of the cooling performance according to the present invention was confirmed.

[Brief description of drawings]

FIG. 1 is a perspective view of an oil rotary pump according to an embodiment of the present invention.

FIG. 2 is a perspective view of a conventional oil rotary pump.

FIG. 3 is a front view of an oil rotary pump according to an embodiment of the present invention and a conventional oil rotary pump.

FIG. 4 is a sectional view of an oil rotary pump according to an embodiment of the present invention at a position of an axial fan.

[Explanation of symbols]

 P: Pump mechanism C: Coupling chamber 10: Pump main body 11: Pump case 12: Pump shaft 20: Motor 21: Motor shaft 30: Coupling 32a: Left side plate 32b: Right side plate 33a, 33b: Slit hole 40: Axial flow fan

Claims (1)

(57) [Scope of utility model registration request] 1. A pump mechanism, a motor, and a coupling chamber for connecting the pump shaft of the pump mechanism and the motor shaft of the motor. The pump mechanism is provided by an axial fan provided in the coupling chamber. In an air-cooled oil rotary pump, one of the left and right case side plates of this coupling chamber is provided with slit holes for taking in air to the axial fan from the height of the pump shaft to the vicinity of the lower end, and the other case The oil rotary vacuum pump is characterized in that the slit holes for introducing air into the axial fan are asymmetrical by providing the slit holes on the side plates from near the height of the pump shaft to near the upper end.