JP2003214368A - Rotary pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of reduced sealing ability of some conventional seal material for the rotary pump such that the seal material is freely fit to the annular groove provided on the end face of the rotor and is forced onto the sealing surface utilizing pressure difference applied to the seal material however, when pressure difference is not generated to the seal material during stop condition, etc., the seal material is not pressed onto the sealing surface. <P>SOLUTION: A rubber annular elastic body 42 and the annular seal material 43 are installed in the annular groove formed on the end face of the outer rotor 15. The resilience of the elastic body 42 continuously presses the seal material 43 onto a side plate 6 and a center plate 8. With this composition, the seal material 43 is pressed onto the sealing surface by the elastic body 42 even if almost no pressure difference is acting on the seal material 43 and favorable sealing ability is ensured. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary pump that utilizes the volume change of a closed space formed between a cylinder and a rotor, and is a technique suitable particularly for a non-lubricated gas compressor. .

[0002]

2. Description of the Related Art As a conventional technique of this type of rotary pump,
The technique disclosed in Japanese Patent Laid-Open No. 59-51191 is known. In the rotary pump disclosed in this publication, a sealing material is mounted in an annular groove provided on an end surface (a plate facing surface) of a rotor in a loosely fitted state. It is pressed against the plate) to ensure the sealing property.

[0003]

However, according to the conventional technique disclosed in the above publication, when the pressure difference hardly acts on the sealing material, such as when the rotary pump is stopped,
The sealing material will not be pressed against the sealing surface (plate) and the sealing performance will deteriorate. The present invention has been made in view of the above circumstances, and an object thereof is to provide a rotary pump in which the sealing material can maintain a good sealing property even when the pressure difference hardly acts on the sealing material. In offer.

[0004]

According to the invention of claim 1, the rotor is provided with a groove for mounting the sealing material, and the elastic body for pressing the sealing material toward the sealing surface is arranged in the groove. Is characterized by. By providing in this way, the sealing material is pressed against the sealing surface by the elastic body even when the pressure difference hardly acts on the sealing material, such as when the pump is stopped, and good sealing performance is maintained. You can

According to the second aspect of the present invention, an annular groove is provided on the plate-opposing surface of the rotor, and an annular sealing material is mounted in the annular groove. Further, the sealing material is applied to the plate inside the annular groove. It is characterized in that an elastic body that is pressed toward is arranged. With this arrangement, the elastic body presses the sealing material against the plate, which is the sealing surface, even when the pressure difference hardly acts on the sealing material, such as when the pump is stopped. Can be kept.

According to a third aspect of the present invention, in the rotary pump according to the first or second aspect, the elastic body is a rubber member which is elastically deformable. As described above, by using the rubber member as the elastic body,
The effect of can be obtained.

A fourth aspect of the present invention is characterized in that, in the rotary pump according to the first or second aspect, the elastic body is a leaf spring bent in a wave shape. As described above, the effect of claim 1 can also be obtained by using a corrugated leaf spring as the elastic body.

The invention of claim 5 is characterized in that, in the rotary pump according to claim 1 or 2, the elastic body is a compression coil spring. As described above, the effect of claim 1 can be obtained by using the compression coil spring as the elastic body.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described using a plurality of examples and modifications. [First Embodiment] FIGS. 1 to 5 are drawings for explaining a two-cylinder type rolling piston rotary pump (hereinafter referred to as a rotary pump) used for vehicle-mounted hydrogen gas circulation, FIG. 1 is a sectional view taken along the axial direction of the rotary pump, and FIG. 2 is a sectional view of an essential part of the rotary pump as seen from the axial direction.

As shown in FIG. 1, a rotary pump 1 includes a housing 2, two rotors 3 that rotate in the housing 2, and a drive unit 4 that eccentrically drives the two rotors 3.
Have. Reference numeral 5 shown in FIG. 1 is a rubber O-ring for sealing the joint portion of each member.

The housing 2 includes two side plates 6, two cylinders 7 and one center plate 8.
Are laminated and fastened firmly by a plurality of fastening bolts 9. On the upper side of the cylinder 7 in the figure, the cylinder 7 and the rotor 3 generated by the eccentric rotation of the rotor 3
1 that separates the enclosed space between the suction chamber and the compression chamber
1 is installed. The vane 11 is mounted on the upper side of the cylinder 7 so as to be slidable in the vertical direction, and is constantly pressed by the compression coil spring 12 toward the rotor 3. The compression coil spring 12 is mounted so that the vane 11 is constantly pressed by the convex plug 13 fixed to the upper side of the cylinder 7. The pressure of the working fluid is increased by gradually reducing the volume of the compression chamber by the rotation of the rotor 3, and when the pressure rises above an arbitrary set pressure, the discharge valve 14 shown in FIG. 2 opens to compress the working fluid. Are sent out of the rotary pump 1.

The rotor 3 is a cylindrical outer rotor 15
And the inner rotor 16 inside thereof have a double structure, and the outer rotor 15 and the inner rotor 1
An elastic body 17 (rubber O-ring) is arranged between 6 and
The outer rotor 15 is provided so as to allow a minute movement in the radial direction. With this structure, the outer peripheral surface of the rotor 3 can be moved while sliding on the inner peripheral surface of the cylinder 7, and the leakage of the working fluid from the outer peripheral sliding surface of the rotor 3 that divides the compression chamber and the suction chamber can be prevented. Thus, it is possible to suppress the decrease in volume efficiency.

The drive unit 4 is driven by an electric motor (not shown), and the shaft 2 rotatably attached to the housing 2 by a bearing 21.
2 and an eccentric adapter 24 fixed to the shaft 22 via a key 23. The eccentric rotation of the eccentric adapter 24 is transmitted to the inner rotor 16 and the outer rotor 15 via a bearing 25. In this way, by interposing the bearing 25 between the eccentric adapter 24 and the rotor 3, the rotor 3 can rotate, and each of the rotor 3 and the cylinder 7, the rotor 3 and the side plate 6, and the rotor 3 and the center plate 8 can be rotated. Sliding speed is reduced. The eccentric adapter 24 is provided so as to eccentrically rotate the two rotors 3 by shifting them by 180 °, and the balancer 2 is also provided.
6 is provided to balance the rotation. Reference numeral 27 shown in FIG. 1 denotes ring members fixed to both ends of the shaft 22.

The fluid path through which the working fluid flows will be described with reference to the sectional view around the suction hole 31 and the discharge hole 32 of the rotary pump 1 shown in FIG. Here, the fluid path will be described along the flow of the working fluid. The working fluid flowing from the outside of the rotary pump 1 is along the axial direction of the cylinder 7,
After that, it is distributed into the respective cylinders 7 through the suction holes 31 (see the upper left of FIG. 2) which go into the cylinders 7. Cylinder 7
When the working fluid that has flowed into the interior of the compression chamber and has been compressed in the compression chamber rises to a pressure equal to or higher than the set pressure, the working fluid passes through the discharge hole 32 provided on the side of the vane 11 and flows through the discharge valve 14 disposed in the discharge hole 32. After the valve is opened, it is pumped to the outside of the rotary pump 1 through the discharge hole 32 along the axial direction of the cylinder 7. Here, the side surface of the vane 11 on the discharge hole 32 side has a concave shape with a half-moon cutout formed therein for guiding the working fluid to the discharge passage.

The vicinity of the discharge valve 14 will be described with reference to FIGS. 3 and 4. Note that FIG. 3 shows the discharge holes 32 along the axial direction.
FIG. 4 is a sectional view of the periphery and FIG. 4 is a sectional view of the discharge valve 14. As shown in FIG. 3, when there is two or more cylinders 7 and the working fluid discharged from each cylinder 7 is merged into one discharge hole 32 and discharged to the outside of the rotary pump 1 as in this embodiment. As described above, the working fluid discharged from the cylinder 7 on the upstream side passes through the discharge valve 14 on the downstream side, so that a pressure loss occurs when passing through the valve guide 33 that regulates the opening degree of the leaf spring-shaped discharge valve 14. Will end up. Therefore, in this embodiment, as shown in FIG. 4, the working fluid pumped from the upstream side is inclined by inclining the surface (the surface shown in FIG. 4α) of the valve guide 33 through which the working fluid pumped from the upstream side flows. It prevents the flow of the water from being disturbed.

The seal structure of the rotor 3 and the housing 2 will be described with reference to FIG. In addition, FIG. 5 shows the outer rotor 1.
It is an enlarged view of 5 end faces. An annular groove 41 is provided in an end surface of the outer rotor 15 (opposing surface of the side plate 6 and the center plate 8), and an annular elastic body 42 (for example, a rubber member) made of a rubber member is provided inside the annular groove 41.
A rubber O-ring) and a ring-shaped sealing material 43 are attached. The depth of the annular groove 41 is deeper than the thickness (axial length) of the elastic body 42 and shallower than the sum of the thickness of the elastic body 42 and the thickness of the sealing material 43.
Is set in a compressed state. By providing in this way, the restoring force of the elastic body 42 always acts in the direction of pressing the sealing material 43 against the side plate 6 and the center plate 8.

In the rotary pump 1 having the above-mentioned structure, there is almost no pressure difference between the compression chamber and the inner side of the outer rotor 15 even when the pump is stopped, and the pressure difference hardly acts on the sealing material 43. The elastic body 42 strongly presses the sealing material 43 against the side plate 6 and the center plate 8 which are sealing surfaces, and the sealing material 43 can maintain good sealing performance.
Further, the rotary pump 1 adopting the above configuration can avoid the problem that the corrosive fluid constantly invades the inside of the outer rotor 15 (the drive unit 4 etc.) even when the working fluid is the corrosive fluid. The good operation can be maintained for a long time.

[Second Embodiment] A seal structure of a rotor 3 and a housing 2 in the second embodiment will be described with reference to FIG. Note that FIG. 6 is an enlarged view of the end surface of the outer rotor 15. In the second embodiment, a metal leaf spring bent in a wave shape is used as the elastic body 44 that presses the sealing material 43 against the sealing surface. By providing in this way, the same effect as that of the first embodiment can be obtained. Further, by using the elastic body 44 made of a corrugated leaf spring, reliability with respect to strength can be improved. Further, the variation of the pressure for pressing the sealing material 43 against the sealing surface is also caused by the elastic body 42 made of a rubber member (see the first embodiment).
It can be reduced compared to.

[Third Embodiment] A seal structure of the rotor 3 and the housing 2 in the third embodiment will be described with reference to FIG. Note that FIG. 7A is a view of the outer rotor 15 viewed from the axial direction with the seal member 43 removed, and FIG. 7B is an enlarged view of the end surface of the outer rotor 15. In the third embodiment, a plurality of helical compression coil springs are used as the elastic body 45 that presses the sealing material 43 against the sealing surface. The elastic body 45 made of a compression coil spring is arranged in the annular groove 41 at equal intervals as shown in FIG.
As shown in FIG. 7B, a concave portion 46 for accommodating and holding a part of the elastic body 45 (compression coil spring) is formed in the annular groove 41 where the (compression coil spring) is arranged. By providing in this way, the same effect as that of the first embodiment can be obtained.

[Modification] In the above embodiment, an example in which the present invention is applied to a rotary pump that circulates hydrogen gas is shown.
The present invention may be applied to a rotary pump that circulates another gas. Further, the present invention may be applied to a rotary pump (for example, a refrigerant compressor) in which a lubricant is mixed in a working fluid, instead of the non-lubricated rotary pump shown in the above embodiment.
In the above embodiment, the two-cylinder type using the two cylinders 7 and the two rotors 3 is shown as an example of the rotary pump, but the present invention is applied to the one-cylinder type or the three-cylinder or more rotary pumps. May be.

In the above embodiment, the rolling piston type rotary pump is shown as an example of the rotary pump, but the present invention may be applied to other types of rotary pumps. That is, when the sealing material 43 is used to seal the rotationally driven rotor 3 and the cylinder 7, the present invention may be applied so that the sealing material 43 is pressed against the sealing surface. Also,
Even if the seal material 43 that seals the rotor 3 that is driven to rotate and the side surface plate is not an annular shape but a rod shape or a spiral shape, the seal material 43 is pressed against the sealing surface. The present invention may be applied.

[Brief description of drawings]

FIG. 1 is a cross-sectional view taken along the axial direction of a rotary pump.

FIG. 2 is a cross-sectional view of a main part of the rotary pump as seen from the axial direction.

FIG. 3 is a sectional view of a discharge hole along an axial direction.

FIG. 4 is a sectional view of a discharge valve.

FIG. 5 is an enlarged view of an outer rotor end surface.

FIG. 6 is an enlarged view of an outer rotor end surface.

FIG. 7 is a view of the outer rotor as seen from the axial direction and an enlarged view of an end surface of the outer rotor.

[Explanation of symbols]

1 rotary pump 2 housing 3 rotor 6 Side plate 7 cylinders 8 Center plate 15 Outer rotor 41 annular groove 42 Elastic body (rubber member) 43 Seal material 44 Elastic body (corrugated leaf spring) 45 Elastic body (compression coil spring)

Claims (5)

[Claims] 1. A rotary pump that rotates a rotor in a housing having a cylinder and utilizes a volume change of a sealed space formed between the cylinder and the rotor, wherein a sealing material is attached to the rotor. A rotary pump, wherein a groove is provided, and an elastic body that presses the sealing material toward a sealing surface is arranged in the groove. 2. A rotary pump utilizing a volume change of a sealed space formed between the cylinder and the rotor, the rotor being rotated in a housing having a cylinder and plates for closing both ends of the cylinder. An annular groove is provided on the plate-opposing surface of the rotor, and an annular sealing material is mounted in the annular groove. Further, an elastic body that presses the sealing material toward the plate is provided inside the annular groove. A rotary pump characterized by being arranged. 3. The rotary pump according to claim 1 or 2, wherein the elastic body is an elastically deformable rubber member. 4. The rotary pump according to claim 1 or 2, wherein the elastic body is a leaf spring bent in a wave shape. 5. The rotary pump according to claim 1 or 2, wherein the elastic body is a helical compression coil spring.