JPH01130079A - Rotary pump - Google Patents

Abstract

PURPOSE:To improve the efficiency of a pump as well as to facilitate the manufacture of it by letting either of the inner circumferential surface of a casing or the outer circumferential surface of a rotor be composed of an elastic body. CONSTITUTION:A rotor 2 in a circular form arranged in a casing 3 is so mounted on the eccentric shaft section 10 of a driving shaft 1 as to be loosely rotatable via a bearing 11, and is formed into one wherein the inner circumferential body made of an elastic body 21 in a ring form is coupled outwardly with a fixture 22 in the same ring form. And numbers of projections 23 ranged over a whole length in the axial direction are arranged at equal intervals in the circumferential direction on the outer circumferential surface of a rotor 2 formed by the elastic body 21. When the rotor 2 is rotated eccentrically while coming in contact with the inner circumferential surface of the casing 3, the projections 23 are deflected toward the circumferential direction, no slip thereby occurs at contacting points between the elastic body 21 and the inner circumferential surface of the casing 3.

Description

[Detailed description of the invention] 【Technical field】

The present invention relates to a rotary pump of a type in which a circular beam is rotated eccentrically within a casing to gradually shift the contact position between the inner circumferential surface of the casing and the outer circumferential surface of the rotor.

[Background technology]

An example of the above type of rotary pump is shown in FIG. A circular rotor 2, which is freely rotatably attached to an eccentric shaft portion 10 of a drive shaft 1 via a bearing 11, is eccentrically rotated within a casing 3 by the rotation of the drive shaft 1, and the casing 3
A shutter 4, which is swingably attached to the rotor 2, is slidably fitted into a groove 20 provided on the outer peripheral surface of the rotor 2. As the rotor 2 eccentrically rotates, the contact position between the outer peripheral surface of the rotor 2 and the inner peripheral surface of the casing 3 gradually shifts, and at this time, the contact position between the outer peripheral surface of the rotor 2 and the inner peripheral surface of the casing 3 changes. As the suction pressurized chamber 5 surrounded by the suction chamber 5 and the shutter 4 moves, its volume changes, and the fluid sucked from the suction port 31 is discharged to the discharge port 32. Here, in this type of rotary pump, the degree of sealing of the suction pressurizing chamber 5 formed between the outer circumferential surface of the rotor 2 and the inner circumferential surface of the casing 3 having a larger diameter than this is related to the discharge pressure. It has a huge impact on the ability to
For this reason, the dimensions of the outer diameter of the rotor 2 and the inner diameter of the casing 3, as well as the amount of eccentricity of the eccentric shaft portion 10, must be kept with extremely high precision, and in order to meet these requirements, advanced design and manufacturing technology is required. It has become. Moreover, as is clear from the fact that the diameter of the rotor 2 inscribed in the casing 3 is different from that of the casing 3, and at the same time, the rotation of the rotor 2 itself is regulated by the shutter 4 (this means that when the rotor 2 comes into contact with the casing 3, The friction loss caused by this sliding causes power loss and reduced efficiency, and the shutter 4
This will give a reaction force to the fitting part between the rotor 2 and the rotor 2.
The rotor 2 is required to have a high degree of strength and durability, and for this reason, including the design and manufacturing technology,
The cost has become quite high.

[Purpose of the invention] The present invention has been made in view of these points, and its object is to provide a rotary pump of this type that has high capacity and efficiency and is easy to manufacture. [Disclosure of the invention]

However, does the present invention include a casing and an eccentric rotating part? lI'
! The outer circumferential surface of the rotor is surrounded by the inner circumferential surface of the casing due to the shift of the contact position between the outer circumferential surface of the rotor and the inner circumferential surface of the casing due to the eccentric rotation of the rotor. In a rotary pump that changes the volume of a suction pressurized chamber, one of the inner circumferential surface of the casing and the outer circumferential surface of the rotor is formed of an elastic body.
The airtightness of the suction pressurization chamber is increased by utilizing the flexure of the elastic body. The present invention will be described in detail below based on the illustrated embodiments.
The figures and FIG.
A ring-shaped metal fitting 22 is attached to the inner peripheral surface of a ring-shaped elastic body 21 through a bearing 11.
It is formed as an insert. In addition, on the outer circumferential surface of the holder 2 formed into an oval shape by the elastic body 21, as shown in FIGS. . On the other hand, the casing 3 provided with the circular cylinder 30 that houses the rotor 2 is! As is clear from Figure @2,
It consists of a main body 33 and a cover 34, and has an inlet 31 and an outlet 32, and supports the drive shaft 1 by bearings 12, 12. Furthermore, one end of the shutter 4 protruding into the casing 3 is swingably supported between the suction port 31 and the discharge port 32. The shutter 4 has a distal end slidably fitted into a groove 20 formed on the outer peripheral surface of the rotor 2, and seal members 40 and 40 are provided on both sides of the shutter. In FIG. 2, 15 is a retaining ring, 24 is an O-ring receiver that holds the O-rings 25 and 26 between the metal fitting 22 and the inner surface of the casing 3, and 28 is integrated with the outer circumference of the axial end surface of the rotor 2. This is an annular projection that is formed to make the outer peripheral side of the rotor 2 airtight or watertight, and at the same time reduce the frictional resistance with the casing 3. Now, in this rotary pump l2, when the rotor 2 is in the position shown in FIG. The suction pressurized chambers 5 surrounded by the suction ports 31 and
and the discharge port 32, and from this state, the rotation of the drive shaft 1 causes the rotor 2 to
If the rotor 2 is eccentrically rotated in the direction shown by the arrow in the figure, the rotor 2 can freely rotate with respect to the eccentric shaft portion 10, and
Since the rotation of the rotor 2 is restricted by fitting with the shutter 4, the rotor 2 gradually shifts the point of contact with the inner peripheral surface of the casing 3, and as shown in FIG. The volume of the suction pressurization chamber 5 connected to the outlet 32 is reduced to discharge to the discharge port 32, and at the same time, the volume of the suction pressurization chamber 5 connected to the suction port 31 is increased to discharge air from the suction port 31. Take an inhalation. As the rotation of the rotor 2 further progresses, as shown in FIG.
As shown in b), the suction pressurization chamber 5, which had been in the suction process, shifts to the pressurization and discharge process, and a new suction pressurization chamber 31 connected to the suction port 31 is created, and as shown in FIG. as well as! @4 Return to the state shown in Figure (c). During this time, the shutter 4 slides within the groove 20 of the rotor 2 and at the same time swings in proportion to the amount of eccentricity of the rotor 2. Here, the discharge pressure in this rotary pump is affected by the degree of sealing of the suction pressurizing chamber 5, and for this reason, the contact area between the outer circumferential surface of the rotor 2 and the inner circumferential surface of the casing 3 is in a state with no gap. However, since the outer peripheral surface of the rotor 2 is formed of the elastic body 21, the dimensional accuracy of the outer diameter of the rotor 2, the inner diameter of the casing 3, or the amount of eccentricity of the eccentric shaft portion 10 is Even if the elastic body 2 is rough,
The deflection of 1 absorbs the roughness of precision and ensures the contact between the outer circumferential surface of the rotor 2 and the inner circumferential surface of the casing 3, and the sliding fitting part with the shutter 4 is also highly airtight or watertight. shall be. Furthermore, due to the difference between the circumferential length of the outer diameter of the rotor 2 and the circumferential length of the inner diameter of the casing 3, when the rotor 2 contacts the inner circumferential surface of the casing 3 due to its eccentric rotation, the rotor 2 and the casing 3 should normally be in contact with each other as described above. However, in this rotary pump, as shown in FIG. 5, as the elastic body 21, especially its protrusion 23, bends in the circumferential direction,
This does not cause slippage at the contact point between the elastic body 21 and the inner peripheral surface of the casing 3, and therefore no sliding frictional resistance acts between the rotor 2 and the casing 3. Note that the shutter 4 provided in the casing 3 does not necessarily have to be swingable, and as shown in FIG. The width of the part is narrow and the width of the back part is wide.
As shown in the figure, the shutter 4 may be formed integrally with the casing 3 if the tip portion of the shutter 4 is provided with a bulge having a circular cross section. In the above embodiment, the outer circumferential surface of the rotor 2 is formed of the elastic body 21, but the inner circumferential surface of the casing 3 may be formed of the elastic body 36, as shown in PIS8. Further, in this case, it is preferable to provide a large number of protrusions 37 on the inner circumferential surface of the elastic body 36, similar to when the outer circumferential surface of the rotor 2 is formed of the elastic body 21. In addition, the present invention is not limited to the form shown in the drawings, but may be of a type in which the rotor 2 that rotates eccentrically within the casing 3 contacts the inner circumferential surface of the casing 3. is casing 3
The shutter 4 may be slidably supported by the rotor 2, or the shutter 4 may be provided on the rotor 2 side.

【Effect of the invention】

As described above, in the present invention, since the inner periphery of the casing or the outer periphery of the rotor is formed of an elastic body, even if the dimensional accuracy of both and the accuracy of the amount of eccentricity of the rotor are slightly rough, the deflection of the elastic body will compensate for this. It absorbs and keeps the suction pressure chamber sealed, increasing the discharge pressure and efficiency. Therefore, it can be manufactured as a synthetic resin molded product and can be provided at low cost, and it also prevents the rotor from slipping against the casing. Since this is replaced by the deflection of the elastic body of the rotor, it is possible to obtain a highly efficient fish with no loss, and the strength required for the rotor is also small.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of one embodiment of the present invention, FIG.
Figures (,) to (d) are cross-sectional views showing the same operation as above, Figure 5 is an enlarged cross-sectional view of the same as above, Figures 6 (a) and (t)) are cross-sectional views of other embodiments, Figure 7 is a cross-sectional view of another embodiment, t5
8 is a cross-sectional view of yet another embodiment, and tjSS is a cross-sectional view of a conventional example, in which 2 is a rotor, 3 is a casing, and 5 is a cross-sectional view of a conventional example.
21 represents an inhalation pressurization chamber, and 21 represents an elastic body. Agent Patent attorney Ishi 1) Tsuyoshi 72 Rotor 3 Casing Fig. 2 Fig. 3 Fig. 5 Fig. 8

Claims (4)

[Claims] (1) It is equipped with a casing and a rotor that is driven to rotate eccentrically and rolls into contact with the inner circumferential surface of the casing, and the outer circumferential surface of the rotor is A rotary pump that changes the volume of a suction pressurizing chamber surrounded by a casing inner circumferential surface and a casing inner circumferential surface, characterized in that either one of the casing inner circumferential surface and the rotor outer circumferential surface is formed of an elastic body. rotary pump. (2) The outer circumferential surface of the rotor is formed of an elastic body having protrusions arranged in the circumferential direction.
Rotary pump as described in section. (3) The rotary pump according to claim 1, wherein the inner peripheral surface of the casing is formed of an elastic body having protrusions arranged in the circumferential direction. (4) Claim 1, characterized in that the shutter is formed integrally with the casing, and the shutter projects from the inner peripheral surface of the casing and slidably fits into a groove provided on the outer peripheral surface of the rotor. Rotary pump as described in section.