JP2003314480A - Pump and method of assembling the pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To assemble a housing, a casing and an end frame of a pump wherein the casing for enclosing a rotor, and the housing and the end frame closing both ends of the casing, are independently fastened with fasteners, by aligning them without causing enlargement in size, complication of machining and the increase of machining man-hours. <P>SOLUTION: The outer peripheries of the housing 1, casing 3 and end frame 2 are respectively provided with socket and spigot joints 21, 23, 24 coming in close contact with the inner surface of an imaginary cylinder. A socket and spigot implement 30 of the cylinder is fitted to the socket and spigot joint 21 of the housing 1, and centering is performed with the socket and spigot implement to assemble the casing 3 and end frame 2. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casing for housing a rotor, a housing for sandwiching the casing and an end frame, and a pump for centering and fastening the casing and the end frame without providing mutual fitting portions. The present invention relates to a method of assembling a pump. Note that the following description will be given by taking the Wankel type vacuum pump as an example.

[0002]

2. Description of the Related Art A Wankel type vacuum pump, as shown in FIGS. 3 and 4, has a triangular rotor 4 inside a casing 3 whose both ends are closed by a housing 1 and an end frame 2.
, The internal gear 5 integrated with the rotor 4 is meshed with the fixed pinion 6, and the rotor 4 is rotated while revolving the crankshaft 8 along the outer periphery of the pinion 6, and the eccentric motion causes the rotor outer periphery and the casing to rotate. A chamber (pump chamber) 12 formed between the inner surface and the inner surface is changed in volume to perform intake and exhaust.

This pump has two chambers 12, and intake air is made to correspond to each chamber 12 and an intake hole 13 (which communicates with an intake port 18) provided in a side housing (housing 1 in the figure) is provided. From).

Exhaust is performed from the exhaust holes 14 provided in the housing 1 through the check valves 15 provided at the outlets of the exhaust holes 14.

Both ends of the crankshaft 8 are supported by the housing 1 and the end frame 2 via bearings 7, and the eccentric shaft 8a of the crankshaft is fitted with the rotor 4 via bearings 9. Therefore, the housing 1, the casing 3, and the end frame 2 need to be centered and fastened.

For the purpose of centering, the housing 1 and the end frame 2 are concentrically fitted to each other by providing interlocking braces 19 and 20 between the casing 3 and the casing 3. The internal gear 5 of the rotor 4 is meshed with the pinion 6, and then the casing 3 is butted against the housing 1. At this time, the casing 3 is rotated in the rotor revolution direction so that the rotor 4 rotating while revolving does not interfere with the inner surface of the casing. It is necessary to finely adjust the posture of the casing by turning it to the position, and the hands and hands 19 and 20 are required for the work.

[0007]

The inner surface of the casing 3 of the Wankel pump has a bilobal shape. The diameter of the anchor 20 provided on the outer periphery of the casing 3 needs to be set with reference to the outer diameter of the casing 3 on the major axis side.
In the structure shown in FIGS. 3 and 4 in which the anchor 20 and the anchor 19 are provided on the outer side thereof, the size and weight of the pump are increased.

Further, a pump for ensuring performance by performing side seal of the rotor 4 by a clearance seal, that is, between the rotor 4 and the housing 1 and between the rotor 4 and the end frame 2.
The pump that minimizes the clearance C between them to reduce the exhaust leakage from the chamber 12 is provided with both ends of the casing 3 and the inner surfaces of the housing 1 and the end frame 2 (sliding surface with the rotor) for managing the clearance C. Although the required flatness and surface roughness are secured by grinding, the protruding anchors 19 become an obstacle, complicating the processing of the housing 1 and the end frame 2, and increasing the number of processing steps.

The present invention aims to eliminate these problems.

[0010]

In order to solve the above-mentioned problems, according to the present invention, a housing, a casing, and an end frame, which are independent of each other, are provided with anchors which are in close contact with the inner surface of a virtual cylinder. The casing and end frame provide the pump with the maximum diameter of the anchor.

Further, one end of the cylindrical shape of the brazing jig is fitted to the brazing jig on the outer circumference of the pump housing described above,
After that, center the casing and the end frame with the anchor on the outer periphery on the inner surface of the anchor jig, and assemble them in order.After fastening the housing, casing and end frame, remove the anchor jig from the end frame side. Provide a way.

[0012]

The pump of the present invention uses the cylindrical brazing jigs fitted to the outer periphery of the housing, the casing and the end frame to fit the respective brazings, and thereby aligns the three members by the method of the present invention. It can be carried out. Therefore, it is possible to reduce the size of the pump by eliminating the anchor (cylindrical portion) 19 provided on the housing 1 and the end frame 2 in FIG.

Further, in the case where the casing outer periphery of the anchor is formed by a plurality of protrusions, the casing outer periphery can be made non-circular to reduce the extraneous weight, and the casing can be made slimmer to reduce the body size, and the pump can be made smaller and lighter. Becomes possible.

[0014]

1 and 2 show an embodiment of the present invention. In the illustrated Wankel-type vacuum pump, a casing 3 is sandwiched between a housing 1 and an end frame 2 (these two are side housings), and the three are connected by bolts B.

A triangular rotor 4 is housed in the casing 3, and an internal gear 5 provided on the rotor 4 meshes with a pinion 6 fixed to the housing 1.

A crankshaft 8 supported by the housing 1 and the end frame 2 is passed inside the rotor 4 through a bearing 7. The eccentric shaft 8a of the crankshaft is arranged concentrically with the internal gear 5. Are fitted to the bearing 9 incorporated in the rotor 4.

The crankshaft 8 is connected to the output shaft of a motor 10. When the crankshaft 8 is rotated by the motor 10, the rotor 4 meshed with the pinion 6 revolves around the pinion 6 while rotating. Reference numeral 11 denotes a weight balancer attached to the crankshaft 8 for the purpose of reducing the vibration generated by the eccentric movement of the rotor 4.

The inner surface of the casing 3 has a bilobal shape slightly larger than the movement trajectory of the apex of the rotor 4, and the chamber 1 formed between this inner surface and the outer peripheral surface between the apexes of the rotor.
The rotational movement of the rotor 4 accompanied by the revolution of the rotor 4 causes a volume change, and intake and exhaust are repeated.

The housing 1 has an intake hole 13 and an exhaust hole 1
The gas in the chamber 12 which has been provided with two 4 each and has moved to the compression stroke is transferred from the exhaust hole 14 to the check valve 15 provided in each exhaust hole.
Through the drain pipe 16 to the outside. Each intake hole 13 communicates with an intake port 18.

An apex seal 17 is incorporated in each apex of the rotor 4 so as to be slidable in the radial direction. The apex seal 17 is pressed against the inner surface of the casing 3 by the centrifugal force generated by the rotation of the rotor, so that the outer circumference of the rotor and the inner surface of the casing. The seal between them is made.

The seal between the rotor 4 and the housing 1 and between the end frame 2 is made between the rotor 4 and the housing 1 and the end frame 2 by making the thickness of the casing 3 slightly thicker than the thickness of the rotor 4. A clearance C for rotating the rotor is generated, and the clearance C is made as small as possible without using the side seal member.

On the outer periphery of the housing 1 on the casing side, there is provided a perfect circular anchor 21 which is concentric with the axial center of the pump.
Further, a plurality of protrusions 22 are provided on the outer periphery of the casing 3 in a scattered manner in the circumferential direction, and the tips of the protrusions 22 are attached to the anchor 21.
The protrusions 22 form the anchor 23 on the outer circumference of the casing aligned on a circle concentric with and having the same diameter. The outer periphery of the casing 3 excluding the protrusion forming portion is substantially parallel to the inner surface, so that the casing 3 is slim and has almost no bulkiness.

On the outer periphery of the end frame 2, the anchor 2
A true circular anchor 24 having the same diameter and the same diameter as 1 is provided.
Like the anchor 23, the anchors 21 and 24 may be configured by aligning the tips of a plurality of protrusions on a perfect circle. The anchors 23 and 24 are required to have the maximum diameter portions of the casing 3 and the end frame 2, respectively.

Reference numeral 30 is an immobilizing jig used when assembling the pump. The internal gear 5 of the rotor 4 is engaged with the pinion 6 fixed to the housing 1 at a designated position to assemble the rotor 4, and the crankshaft 8 is further attached to the bearing 7 in the pinion 6 and the bearing 9 in the rotor 4. insert.

Next, the anchor jig 30 is fitted to the anchor 21 of the housing 1, and then the anchor 23 of the casing 3 is closely attached to the inner surface of the anchor jig 30 to fix the casing 3 to the anchor jig. Centering is carried out at 30, and in this state, the casing 3 is inserted at the abutment point with the housing 1. At this time, the casing 3 is rotated by using the brazing jig 30 as a guide so that the apex portion of the rotor 4 does not interfere with the inner surface of the casing 3 (in order to eliminate the interference due to the influence of the tolerance of the gear), and the casing posture is slightly changed. Make adjustments.

When the work is completed, this time, the end frame 2 provided with the anchor 24 on the outer periphery is centered by the anchor jig 30 and fitted to the crankshaft 8, and the end frame 2 is fitted to the casing 3. It is fastened to the housing 1 with the bolt B via.

After that, the anchor jig 30 is pulled out from the end frame 2 side.

In addition to the above work, the weight balancer 11 is attached to the crankshaft 8, the motor 10 is connected, the lid 25 of the weight balancer chamber is attached, and the like to complete the assembly of the pump.

The bolts B have projections 22 at opposite positions.
The seals 26 on both end surfaces of the casing 3 are disposed between the bolt B and the inner surface of the casing 3 through the elongated holes provided in the casing 3.

Although the Wankel type vacuum pump has been described above as an example, the present invention can be applied to pumps other than the Wankel type pump. A pump to which the present invention is applied is
It does not matter whether it is a vacuum pump or a compression pump.

[0031]

As described above, in the Wankel type pump of the present invention, the housing for fastening and the casing, the casing, and the outer periphery of the end frame are provided with the centering wax, respectively. The assembly can be performed by the method of the present invention in which the inner surface of the cylindrical anchoring jig is fitted, the centering of the three members is performed by the anchoring jig, and the anchoring jig is removed after fastening. There is no need to fit the end frame and casing directly.
Therefore, it is possible to eliminate the increase in the size and weight of the pump due to the installation of the anchor.

[0032] At least, when the anchor on the outer circumference of the casing is formed by providing a plurality of protrusions, the outer circumference of the casing can be made non-circular to remove the extraneous thickness of the casing, which is effective in reducing the size and weight of the pump. Appears more prominently.

Further, since the rotor sliding surfaces of the housing and the end frame and the abutting surfaces against the casing can be aligned on the same plane, the rotor sliding surfaces can be easily processed with a small number of man-hours, and also in terms of productivity and cost. Be advantageous

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a pump according to an embodiment.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view of a conventional Wankel type vacuum pump.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

[Explanation of symbols]

1 housing 2 end frame 3 casing 4 rotor 5 Internal gear 6 pinion 8 crankshaft 8a Eccentric shaft 10 motors 11 weight balancer 12 chambers 13 Intake hole 14 Exhaust hole 15 Check valve 17 Apex Seal 18 Inhalation port 21, 23, 24 22 protrusion 25 lid 26 seal 30 anchor jig

Claims (3)

[Claims] 1. A pump that houses a rotor and forms a pumping chamber between the rotor and the outer circumference of the rotor, and a housing that closes both ends of the casing and an end frame that are independently fastened by fasteners. A pump characterized in that the housing, the casing, and the end frame are each provided with an anchor which closely adheres to the inner surface of the virtual cylinder so that the casing and the end frame have the maximum outer diameter. 2. The pump according to claim 1, wherein at least the outer circumference of the casing is formed by aligning the tips of a plurality of protrusions scattered on the outer circumference on a circle concentric with the pump. 3. One end of the cylindrical shape of the brazing jig is fitted to the brazing wire on the outer circumference of the housing of the pump according to claim 1, and thereafter, the casing and the end frame having the brazing material on the outer circumference are connected to the brazing jig of the brazing jig. A method for assembling a pump, which comprises centering on an inner surface and sequentially assembling, and after fastening a housing, a casing, and an end frame, pulling out an anchor jig from the end frame side.