JP2753339B2 - Multi-function pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to a multifunctional pump in which a vacuum pump and a compressor are arranged on the same rotating plane.

<Prior Art> A multifunctional pump in which a plurality of vanes are provided slidably in the radial direction at equal intervals on the circumference of a rotor eccentrically rotating in a pump housing, and a compressor and a vacuum pump are arranged on the same rotation plane is known. It is.

<Problem to be Solved by the Invention> In this type of multifunctional pump, in a compressor region, when the vane ejection force due to the rotational centrifugal force is smaller than the vane pushing force due to the compressor pressure, the outer periphery of the rotor is inside the pump housing. A pressure leaks from the vane tip to the vacuum side in the seal section where the volume of the pump chamber shifts from the contraction operation to the expansion operation in contact with the circumference, and the vacuum performance is reduced. In order to prevent this, it is necessary to manage the clearance between the outer periphery of the rotor in the seal section and the inner periphery of the pump housing. Then, a very precise tolerance is required, and there is a problem that the clearance management is extremely difficult.

<Means for Solving the Problems> The present invention has been made in view of the above problems,
A rotor is rotatably housed in the pump housing, and a plurality of vanes are provided on the circumference of the rotor so as to be slidable in the radial direction. The vanes are formed between the pump housing and the rotor by the vanes. The space is circumferentially divided into a plurality of pump chambers, a vacuum suction port is opened at the beginning of the expansion pump chamber whose volume increases due to the rotation of the rotor, and a compressor suction port is opened at the end of the expansion pump chamber. A pump having a compressor discharge port opened at the end of a contraction pump chamber whose volume is reduced by rotation of the rotor, wherein a plastic coating layer is formed on the outer periphery of the rotor.

<Operation> With the above configuration, by rotating the rotor inside the pump housing by rotating the rotor, the coating layer is pressed against the inner peripheral surface of the pump housing in the seal section. The film thickness adapts plastically to the pump housing and keeps the clearance in the seal section to a minimum.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings. Reference numeral 10 denotes a pump housing.
It comprises a center housing 12 having a hollow hole 11, and a pair of side housings 13, 14 bolted to both sides of the center housing 12. In the site housings 13 and 14, a rotating shaft 15 penetrating through the hollow hole 11 has a hollow hole.
It is rotatably mounted around an axis which is eccentric with a predetermined amount by 11 axes. A rotor 17 is mounted concentrically on the rotating shaft 15, and the rotor 17 is rotatably housed in the hollow hole 11. A plurality of vane grooves are formed radially on the circumference of the rotor 11 at equal angular intervals on the circumference, and the vanes 18 are slidably held in these vane grooves. Both ends of the rotor 17 and the vane 18 are slidably in contact with the inner surfaces of the side housings 13 and 14 with an appropriate side clearance.

Annular grooves 17A, 17B are formed on both side surfaces of the rotor 17, and vane pressing rings 21, 22 are formed in these annular grooves 17A, 17B.
Are rotatably accommodated in the radial direction. The outer peripheries of the vane pressing rings 21 and 22 contact both sides of the inner ends of the plurality of vanes 18 to press the vanes 18 against the inner surface of the hollow hole 11.

A crescent-shaped space is formed in the hollow hole 11 with the rotor 17, and the space is circumferentially divided into a plurality of pump chambers 23 by a plurality of vanes 18. Each pump room 23
Changes in volume due to the rotation of the rotor 17. For example, rotor 17
When the rotor rotates in the direction indicated by the arrow in FIG.
, The volume of each pump chamber located in the lower half increases, and the volume of each pump chamber located in the upper half decreases. Hereinafter, each pump chamber located in the lower half is called an expansion pump chamber, and each pump chamber located in the upper half is called a contraction pump chamber.

A vacuum suction port 31 is opened at the start end of the expansion pump chamber in the rotation direction, and a compressor suction port 32 is opened at the rotation end of the expansion pump chamber. A compressor discharge port 33 is opened at the end of the contraction pump chamber in the rotation direction. Vacuum suction port 31
Is connected to a vacuum tank (not shown), the compressor suction port 32 is connected to the atmosphere via an air breather (not shown), and the compressor discharge port 33 is connected to an operating device (not shown).

Further, the side housing 14 is provided with a drain port 41 and an oil storage space 42 in front of the drain port 41.
Although not shown, the rotating shaft is attached to the side housing 13.
A lubrication port for lubricating the 15 bearings is provided separately, and a lubrication oil pump is connected to this port. Therefore, when the lubricating oil that has lubricated the bearing portion is drained, a part of the lubricating oil is stored in the oil storage space.

The present invention relates to a multi-function pump as described above,
A plastic film layer 51 is formed on the outer periphery of the film 17. This coating layer 51 is formed by, for example, a chemical conversion treatment with a phosphate or a surface treatment with molybdenum coating.

In the above configuration, it is assumed that the rotor 17 is rotated in the direction of the arrow in FIG. Among the pump chambers 23 partitioned by the plurality of vanes 18, the volume of the expansion pump chamber increases, and the volume of the contraction pump chamber decreases. Now, assuming that the pump chamber immediately after the volume shifts from the decreasing action to the increasing action is designated as 23A, this pump chamber 23A is first opened to the vacuum suction port 31 with the rotation of the rotor 17, and air is sucked from the vacuum tank. To perform a vacuum action, and then to pump chamber 23
A continues to expand while passing through the vacuum suction port 31 and maintaining a sealed state, and the inside of the pump chamber 23A is maintained in a negative pressure state. When the pump chamber 23A opens to the compressor suction port 32, air in the atmosphere is sucked from the compressor suction port 32 into the pump chamber 23A in a negative pressure state. Thereafter, the pump chamber 23A shifts to a contraction pump chamber, and the air in the pump chamber 23A is compressed.

Thus, the pump chamber 23A is
, Compressed air is discharged from the compressor discharge port 33.

In the above-mentioned pumping operation, the factor for improving the pumping performance is that the clearance of the seal section 50 that transitions from the contraction pump chamber to the expansion pump chamber is sealed in a state where the clearance is optimal.

Therefore, in the present invention, the rotor layer 17 having the coating layer 51 having a uniform thickness formed on the outer periphery is assembled into the pump housing 10 and rotated, so that the coating layer 51 is formed on the inner peripheral surface of the pump housing 10 in the seal section 50. The thickness of the coating layer 51 is adjusted to the inner peripheral surface of the pump housing 10 to keep the clearance of the seal section 50 to a minimum.

In particular, due to variations in rotor outer diameter and pump housing inner diameter accuracy, as shown in FIG.
When the center deviation amount L of the center 02 of the rotor 17 assembled with respect to the normal eccentric center 01 of the rotor 17 is present, the thickness of the coating layer 51 is increased by pressing against the inner peripheral surface of the pump housing 10. The outer periphery of the coating layer 51 changes plastically into a film t1-t2,
It becomes a concentric circle with respect to the rotation center of 17 and the above-mentioned center deviation amount L
To ensure that the seal section 50 has a minimum proper clearance.

<Effects of the Invention> As described above, according to the present invention, in a pump configured to perform the functions of a vacuum and a compressor in one rotation plane, since a plastic film layer is formed on the outer periphery of the rotor, Even if there is some variation in the accuracy of each part, the clearance of the seal section is corrected to the minimum by plastic change due to the initial adaptation of the coating layer to the pump housing, pump performance is improved, and the coating layer improves seizure resistance. It has a great effect.

[Brief description of the drawings]

The drawings show an embodiment of the present invention, and FIG.
FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 10 Pump housing, 11 Hollow hole, 15 Rotary shaft, 17 Rotor, 18 Vane, 23 Pump chamber, 31
... vacuum suction port, 33 ... compressor discharge port, 50 ... seal section, 51 ... coating layer.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F04C 18/344 351 F04C 25/02 F04C 23/00

Claims (1)

(57) [Claims] A rotor is rotatably housed in a pump housing, and a plurality of vanes are provided on a circumference of the rotor so as to be slidable in a radial direction, and are formed between the pump housing and the rotor by the vanes. The formed crescent-shaped space is divided into a plurality of pump chambers on the circumference, and a vacuum suction port is opened at the start end of the expansion pump chamber whose volume increases due to the rotation of the rotor, and at the end of the expansion pump chamber. A pump in which a compressor suction port is opened and a compressor discharge port is opened at an end of a contraction pump chamber whose volume is reduced by rotation of the rotor, wherein a plastic coating layer is formed on an outer periphery of the rotor. Multifunctional pump.