JPS61247889A - Hydraulic pump - Google Patents

Abstract

PURPOSE:To make compact by providing a projected/recessed band for pumping out from the inner to the outercircumference on the surface of a disc at the flow-in path side while providing a projected/recessed band for pumping in from the outer to the inner circumference on the surface at the delivery side. CONSTITUTION:A casing 3 for containing a disc 1 is provided with a suction port 4 and a delivery port 5. First projected/recessed band 6 is formed with a groove partitioned by the curves (b), (c) and the remaining section on the surface of said disc 1 at the suction port side while second projected/recessed band 7 is formed in the opposite direction from said band 6 on the other surface or the surface at the delivery port side. Consequently, a small hydraulic pump can be obtained by simply rotating single disc in the casing.

Description

Description: TECHNICAL FIELD This invention relates to fluid pumps, particularly rotary fluid pumps suitable for obtaining relatively small flows of pressurized fluid.

(Prior Art) Conventionally, as a pump for obtaining a small flow rate of pressurized fluid, for example, a small flow rate of pressurized air of 0.2 to 0.5 atm, an air supply pump installed in an aquarium fish tank is a typical example. As shown in the figure, the diaphragm is moved back and forth at high speed using the vibrator of the magnetic device.
Generally, air is supplied by opening and closing valves provided at the air intake port and the air discharge port, respectively, during intake and exhaust. However, pumps with such diaphragms and valves have short lifespans due to fatigue damage of the valves that open and close at high speeds, and they are reciprocating pumps that avoid the generation of vibration noise. It is extremely difficult to do so, and it cannot be used in small consumer devices. On the other hand, centrifugal blowers also exist as air pumps, and although they are suitable as a source of a large amount of low-pressure air, the pressurizing pressure is only about 0.1 atm, so
The generated pressure is too small to be used as a pressurized air supply source for an air bearing reservoir.

(Objective) The object of the present invention is to provide a compact and highly reliable fluid pump, and more specifically, to a pressurized air supply source for static air bearings in information equipment and other devices such as high-speed laser printers and laser discs. The object of the present invention is to provide a suitable fluid pump.

(Structure) The fluid pump of the present invention is composed of a rotationally driven disk and a casing that surrounds the disk to form a pressurized fluid passage.
A concavo-convex band divided by a curve that pumps out from the inner circumference toward the outer circumference, and a concavo-convex band that pumps in from the outer circumference toward the inner circumference on the disk surface on the fluid discharge port side or on the casing surface facing the disk. Each band is formed.

The present invention will be explained below with reference to embodiments of the drawings.

In FIG. 1, reference numeral 1 indicates a disk fixed to the tip of a shaft 2 which is rotationally driven by a suitable motor (not shown), and 3 indicates its casing. A fluid inlet 4 formed around the shaft 2 is provided in one side wall of the casing 3, and a fluid outlet 5 is provided in the center of the other side wall.

As shown in FIG. 2, on the surface of the fluid inlet side of the disk l, there is a groove extending from the center to the outer periphery of the disk and toward the rear in the rotational direction of the disk as indicated by arrow a. Depth 20 ~ divided by curved line and C
A first uneven band 6 is formed by the 120 μm groove and the remaining part, and the first uneven band 6 is formed on the other surface, that is, the surface on the fluid discharge port side, as shown in FIG. The disk was tilted in the opposite direction, that is, toward the front in the direction of rotation of the disk. A second uneven band 7 similar to the first uneven band is formed. The curve forming the uneven zone may be a spiral, a circular arc, or a part of an involute curve. The first uneven band and the second uneven band are made to have the same depth, or the first uneven band is slightly deeper. Further, the depth of the first uneven zone may be uniform, but in order to improve the performance as a pump, it is desirable that the depth becomes gradually deeper from the outer circumference toward the center. The gap between the disk surface and the inner wall surface of the casing is set to 10 to 30 μm, and an inflow passage 8 is formed between the first uneven band surface and the casing, and a fluid passage 9 is formed between the second uneven band surface and the casing. Each is formed.

The disk 1 is rotated at approximately 6,000 to 15,000 rpm, and the air in the inlet passage 8 is compressed from its inner circumference to its outer circumference, and then in the outlet passage 9 from the outer circumference to its inner circumference. The fluid that has flowed in flows out from the discharge port 5. In this case, it is important that the pressure is high even if the flow rate is small. The fluid flow behavior in this pump is different from that of a centrifugal pump.

Although the viscous force of the fluid is the main force, the action of the centrifugal pump is also added to the fluid passage. Diameter 90
When the mm disc is rotated at 900 rpm and the flow rate is zero, the pressure inside the pump is 0.2 atm on the inlet passage side.
A pressure of 0.1 atm on the outflow passage side and 0.3 atm overall was obtained.

The pressure of the outflow air becomes smaller as the flow rate increases. Figure 4 is a curve showing the relationship between the pressure and flow rate of outflow air when the size of the gap between the disk surface and the inner wall surface of the casing is used as a parameter.
2 represents medium and L3 represents small.

The second uneven band provided on the fluid discharge side may be provided on the surface 3a of the casing 3 facing the disk instead of being provided on the disk surface. In this case, the second uneven band is formed in the same direction as the first uneven band, that is, inclined in the direction opposite to the rotational direction of the disk.

FIG. 5 shows an example of a specific structure of a fluid pump integrated with a drive motor, in which the shaft 12 of the disk 11 is supported at both ends by ball bearings 20 provided in the casing 13. A rotor 22 of a motor 21 is fixed to one shaft end. motor 2
1 is a well-known motor mainly composed of a drive coil 24 fixed to a case 23 and a magnet 25 fixed to a rotor 22 driven by the coil.

Air flowing in from the suction port 26 provided in the motor case 23 passes through a filter 27 provided in the suction port 26 , a hole 28 provided in the rotor 22 , and a filter 27 provided in the suction port 26 . Suction port 29 provided in the casing 13. It passes through the inlet passage 16, the outlet passage 17, and the outlet 15 of the casing 13, and is sent from the outlet 30 to, for example, an air bearing for a scanner of a high-speed laser printer via a suitable air supply pipe.

The pump of the present invention can pump not only air but also air by appropriately adjusting the depth of the uneven zone of the disk and the gap between the inflow and outflow passages.
Applicable to water and other liquids.

(Effects) According to the present invention, it is possible to obtain a small and highly reliable fluid pump that rotates only one disk within a casing.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a fluid pump showing an embodiment of the present invention, FIG. 2 is a plan view showing one side of a disk constituting the pump, FIG. 3 is a plan view showing the other side, and FIG. The figure is a diagram showing the relationship between the pressure of outgoing air and the flow rate of air, and FIG. 5 is a sectional view showing one side of the fluid pump of the present invention integrated with a drive motor. 1... Disc, 3... Casing, 3a.
...Casing inner surface, 4...Fluid inlet, 5...
...Fluid discharge port, 6...First uneven band, 7...
Second uneven zone.

Claims (1)

[Claims] A disk that is driven to rotate, supports the central axis of rotation of this disk, surrounds the periphery and both sides of the disk, has a fluid intake port near the center of one side wall, and a fluid discharge port near the center of the other side wall. casings, each having a casing, which is defined on the fluid inlet side surface of the disk by a curved line that extends from the center to the outer circumference of the disk and tilts toward the rear in the rotational direction of the disk. A first uneven band is formed on a surface of the disk on the fluid outlet side, and a second uneven band is formed in an opposite direction to the first uneven band, or a second uneven band is formed on a surface of the disk on the fluid outlet side, or opposite to the disk on the fluid outlet side. A fluid pump characterized in that a second uneven band is formed in the same direction as the first uneven band on a casing surface.