JP2000205148A - Multistage route pump and manufacture of rotor housing of multistage route pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form the wall surface of a pump chamber with high precision by combining a plurality of block pieces about the axial line of a rotating shaft with a plurality of bulkheads for partitioning adjacent pump chambers to constitute a rotor housing. SOLUTION: In the manufacture of a rotor housing, rough block pieces forming the bases of block pieces 17, 18 are firstly die-molded. Rough circumferential wall surfaces and rough positioning grooves are preliminarily formed on the inside wall surfaces of the rough block pieces. The die-molded rough block pieces are temporarily connected, and the rough circumferential wall surface and rough positioning grooves are finished in the state keeping this connected state. Wall pieces 37, 38 formed separately from the block pieces 17, 18 are then press fitted to the positioning grooves. After the wall piece 37 and the wall piece 38 are assembled to the block piece 17 and the block piece 18, respectively, the connecting surfaces 171, 181 of the block pieces 17, 18 and the connecting surfaces of the wall pieces 37, 38 are finished by grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a state in which a plurality of rotating shafts are arranged in parallel, rotors are arranged on the respective rotating shafts, rotors on adjacent rotating shafts are engaged with each other, and the rotors are engaged with each other. The present invention relates to a multi-stage roots pump formed in a rotor housing such that a plurality of pump chambers accommodating a plurality of rotors as one set are arranged in the axial direction of the rotation shaft, and a method of manufacturing the rotor housing.

[0002]

2. Description of the Related Art In a multi-stage roots pump disclosed in Japanese Patent Application Laid-Open No. H8-14172, a rotor housing forming a pump chamber so as to be arranged in a plurality in the axial direction of a pair of rotating shafts is formed by joining a pair of outer shells. It is configured. A plurality of partitions are integrally formed in each outer shell, and the partitions of one outer shell and the partitions of the other outer shell are opposed and joined. The partition walls opposingly joined divide the plurality of pump chambers in the axial direction of the rotation shaft.

[0003]

The rotor housed in the pump chamber rotates in the pump chamber to pump the fluid, but in order to efficiently pump the fluid, the rotating rotor and an arbitrary portion on the wall surface where the pump chamber is formed. It is important to ensure a minute clearance with high precision and uniformity. Processing of the inner peripheral surface of the outer shell integrally formed with the partition must be performed separately for a pair of outer shells, but a part of the inner peripheral surface of the pump chamber accommodating the rotating rotor is a circumferential surface, and The outer shell is joined at this circumferential portion. Therefore, processing the inner peripheral surface of each outer shell separately makes it difficult to secure a highly-accurate processed surface of the circumferential surface when a pair of outer shells are joined to form a rotor housing. Further, the end face of the partition wall, which forms the wall surface of the pump chamber, is processed using a side cutter. However, it is difficult to perform processing for obtaining a high flatness. Furthermore, it is necessary to machine the wall surfaces of the plurality of pump chambers one by one, which increases the working time for the machining.

A first object of the present invention is to make it possible to form a wall surface of a pump chamber of a multi-stage roots pump with high precision. A second object is to reduce the manufacturing time of the rotor housing.

[0005]

For this purpose, the present invention provides a method of arranging a plurality of rotating shafts in parallel, arranging rotors on each of the rotating shafts, and engaging rotors on adjacent rotating shafts with each other. A multi-stage roots pump formed in a rotor housing such that a plurality of pump chambers accommodating a plurality of meshed rotors as a set are arranged in the axial direction of the rotating shaft. The cylinder block that forms the peripheral wall surface of the chamber and a plurality of partition walls that partition adjacent pump chambers are separately provided, and the cylinder block is configured by joining a plurality of block pieces in a direction around the axis of the rotation shaft. Then, the rotor housing is configured by combining the plurality of block pieces and the plurality of partition walls.

[0006] The structure in which the cylinder block composed of a plurality of block pieces and the partition are separated allows high-precision machining of the wall surface for forming the pump chamber and shortens the time required for manufacturing the rotor housing.

According to a second aspect of the present invention, in the first aspect,
The axes of the plurality of rotation shafts are on a first plane, and the cylinder block is joined on a second plane passing through a straight line at an intermediate position between the axes of the plurality of rotation shafts on the first plane. And a pair of block pieces.

The cylinder block has a two-part structure consisting of a pair of block pieces joined on a second plane. The configuration in which the cylinder block is divided into two is the simplest in terms of production.

According to a third aspect of the present invention, in the second aspect,
The second plane was the same as the first plane. The configuration in which the second plane is the same as the first plane facilitates setting of the shape of the pump chamber for increasing the pumping efficiency.

According to a fourth aspect of the present invention, in any one of the second and third aspects, the cylinder block is
It consisted of a pair of block pieces having the same peripheral wall shape.

[0011] Such a shape of the pair of block pieces enhances the manufacturing efficiency of the block pieces. According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the partition is constituted by a pair of wall pieces joined on a second plane passing through the straight line.

The partition has a two-part structure consisting of a pair of wall pieces joined at the second plane. The configuration in which the partition is divided into two is the simplest in terms of production. In the invention of claim 6, in any one of claims 1 to 5, a plurality of positioning grooves are formed in parallel on an inner wall surface of the plurality of block pieces, and the partition wall is formed in the positioning groove. I fit it.

The configuration in which the partition is fitted in the positioning groove makes it possible to ensure a high precision and uniform clearance between the wall of the pump chamber formed by the partition and the rotor.

According to the invention of claim 7, in claim 6,
The partition was pressed into the positioning groove. The configuration in which the partition is press-fitted into the positioning groove is optimal with respect to ease of assembling the cylinder block and the partition.

According to the invention of claim 8, the rough block pieces of the plurality of block pieces are temporarily joined so as to form a cylinder block forming the peripheral wall surface of the pump chamber, and the plurality of pumps are held in a state where this joining is maintained. The peripheral wall surface of the chamber was formed by grinding.

In the state where the coarse block pieces of the plurality of block pieces are joined, the arc-shaped wall surfaces of the plurality of pump chambers can be collectively processed with high precision. According to the ninth aspect of the present invention, in the eighth aspect, a positioning groove for fitting a plurality of partition walls that partition adjacent pump chambers is formed before or after the grinding of the peripheral wall surface.

According to a tenth aspect of the present invention, in the ninth aspect, after the peripheral wall surface is ground and after the positioning grooves are formed, the wall pieces constituting the partition walls are pressed into the positioning grooves of the respective block pieces. .

The rotor is assembled into an assembly of the block pieces and the wall pieces after the wall pieces are pressed into the positioning grooves of the respective block pieces. The work procedure of assembling the rotor into the assembly of the block piece and the wall piece after press-fitting the wall piece into the positioning groove of the block piece improves the workability of assembling the rotor housing.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, a multi-stage roots pump 10
A front housing 13 is joined to a front end of the rotor housing 12 through a partition plate 14, and a rear housing 15 is connected to a rear end of the rotor housing 12 by a partition plate 16.
Are joined through. The rotor housing 12 includes a cylinder block 11 and a plurality of partition walls 33, 34, 35, 3.
6 As shown in FIG.
1 comprises a pair of block pieces 17 and 18, each partition 3
3, 34, 35 and 36 are composed of a pair of wall pieces 37 and 38. The space between the partition plate 14 and the partition wall 33 is a first pump chamber 39, and the space between the partition walls 33 and 34 is a second pump chamber 40. The space between the partitions 34, 35 is a third pump chamber 41, and the space between the partitions 35, 36 is a fourth pump chamber 42. The space between the partition 36 and the partition plate 16 serves as a fifth pump chamber 43.

The front housing 13 and the rear housing 15 have a pair of rotating shafts 19, 20 bearings 21, 22.
It is rotatably supported through. Both rotating shafts 19, 2
0 are arranged in parallel with each other. The rotating shaft 19 is passed through an insertion hole 49 between the hole forming walls 376 and 386 of the wall pieces 37 and 38, and the rotating shaft 20 is inserted through a through hole 50 between the hole forming walls 377 and 387 of the wall pieces 37 and 38. Has been passed through.

A plurality of rotors 23, 24,
25, 26, 27 are integrally formed, and the same number of rotors 28, 29, 30, 31, 32 are integrally formed on the rotating shaft 20. The rotors 23 to 32 are
Are seen to be in the directions of the axes 191 and 201 of FIG. The thicknesses of the rotors 23, 24, 25, 26, 27 are reduced in this order, and the rotors 28, 29, 30, 3
The thicknesses of 1, 32 are reduced in this order. Rotor 2
3 and 28 have the same thickness, and the rotors 24 and 29 have the same thickness. The rotors 25 and 30 have the same thickness,
The rotors 26 and 31 have the same thickness. Rotor 27,3
2 has the same thickness. The rotors 23 and 28 are housed in the first pump chamber 39 in a state of meshing with each other, and the rotors 24 and 29 are housed in the second pump chamber 4 in a state of meshing with each other.
0. The rotors 25 and 30 are housed in the third pump chamber 41 in a state of meshing with each other, and the rotors 26 and 31 are in a state of meshing with each other in the fourth pump chamber 42.
Is housed in The rotors 27 and 32 are housed in the fifth pump chamber 43 in a state of being engaged with each other.

A driving section 44 is mounted on the rear housing 15. The rotating shafts 19 and 20 are for the rear housing 1
5 and protrudes into the drive unit 44, and each rotating shaft 1
Gears 45 and 46 are fastened to the projecting end portions of the gears 9 and 20 in a state where the gears 45 and 46 mesh with each other. The rotating shaft 19 is rotated in the direction of arrow R1 in FIGS. The rotation of the rotating shaft 19 is transmitted to the rotating shaft 20 via the gears 45 and 46, and the rotating shaft 20 rotates in the opposite direction to the rotating shaft 19 as shown by an arrow R2 in FIGS.

As shown in FIGS. 1 and 7, a passage 371 is formed in the wall piece 37, and an entrance 373 of the passage 371 is formed on an end surface 372 of the wall piece 37. A pair of circumferential wall surfaces 174 and 175 are provided on the inner circumferential wall surface of the block piece 17.
Are formed. A plurality of positioning grooves 172 are formed on the inner peripheral wall surface of the block piece 17 in parallel with each other, and the wall piece 37 is press-fitted into each positioning groove 172. FIG.
As shown in FIG. 8, a passage 381 is formed in the wall piece 38, and an outlet 383 of the passage 381 is formed on an end surface 382 of the wall piece 38. A pair of circumferential wall surfaces 184 and 185 are formed on the inner circumferential wall surface of the block piece 18. A plurality of positioning grooves 1 are formed on the inner peripheral wall of the block piece 18.
82 are formed, and each positioning groove 182 has a wall piece 3.
8 is press-fitted. The rotors 23 to 27 are circumferential wall surfaces 17
4 and 184 while maintaining a small clearance, and the rotors 28 to 32 rotate while maintaining a small clearance between the circumferential wall surfaces 175 and 185.

As shown in FIG. 2 to FIG.
7, 18 are circumferential wall surfaces 174, 175, 184, 185
Are the same shape. Block piece 17,
The joining surfaces 171 and 181 of 18 are joined on the plane S1, and the joining surfaces 374 and 384 of the wall pieces 37 and 38 are joined on the plane S1. The passages 371 of the wall pieces 37, 38 joined to each other
381 is connected.

As shown in FIG. 2 and FIG.
8, a fluid inlet 183 is formed so as to communicate with the first pump chamber 39. As shown in FIGS. 5 and 7,
A fluid discharge port 173 is formed in the block piece 17 so as to communicate with the fifth pump chamber 43. Fluid inlet 18
The fluid introduced from 3 into the first pump chamber 39 is pressure-fed from the inlet 373 of the partition wall 33 via the passages 371 and 381 to the second pump chamber 40 by the rotation of the rotors 23 and 28. The fluid introduced into the second pump chamber 40 is rotated by the rotation of the rotors 24 and 29 from the inlet 373 of the partition wall 34 to the outlet 38 via the passages 371 and 381.
The pressure is sent from 3 to the third pump chamber 41. Similarly, the third
From the pump chamber 41 to the fourth pump chamber 42 and from the fourth pump chamber 42 to the fifth pump chamber 43, the fluid flows through the passages 371,
381. The fluid pumped to the fifth pump chamber 43 is discharged from the fluid discharge port 173 to the outside.

The rotor housing 12 is manufactured as follows. First, the rough block pieces 47 and 48 shown in FIG. 6 on which the block pieces 17 and 18 are based are molded. Coarse circumferential wall surfaces 471, 47 are provided on the inner peripheral wall surfaces of the coarse block pieces 47, 48.
2,481,482 and coarse positioning grooves 473,483
Are formed in advance. Molded coarse block piece 4
7, 48 are temporarily joined as shown by the solid lines in FIG. 6, and rough circumferential wall surfaces 471, 472,
481, 482 and rough positioning grooves 473, 483 are finished. By performing these finishing processes, the circumferential wall surfaces 174, 175, and 18 shown in FIGS.
4, 185 and positioning grooves 172, 182 are formed.

Next, as shown in FIG. 9, the wall pieces 37 and 38 formed separately from the block pieces 17 and 18
72,182. Block piece 17 and wall piece 37
After the wall pieces 38 are assembled to the block pieces 18, the joining surfaces 171 and 18 of the block pieces 17 and 18 are assembled.
1 and the joining surfaces 374, 384 of the wall pieces 37, 38 are ground. The fluid inlet 183 and the fluid outlet 173 are formed thereafter. In the first embodiment, the following effects can be obtained.

(1-1) Between the circumferential wall surfaces 174 and 184 of the cylinder block 11 and the rotating rotors 23 to 27, and between the circumferential wall surfaces 175 and 185 and the rotating rotors 28 to 32.
Strict clearance accuracy is required. In a state where the pair of coarse block pieces 47 and 48 are joined, the rough circumferential wall surfaces 471 and 481 and the circumferential wall surfaces 472 and 482 are processed to form the circumferential wall surfaces 174 and 184 and the circumferential wall surfaces 175 and 185.
In the finishing process, the circumferential wall surfaces 174 and 184 are finished in a series and the circumferential wall surfaces 175 and 184 are finished.
185 are finished in a series. In addition, the thickness of the rough block pieces 47 and 48 in the state of being joined and held is made uniform in a series, and the occurrence of distortion during grinding is also made uniform in any circumferential direction of the inner peripheral wall. Accordingly, the circumferential wall surfaces 174 and 184 and the circumferential wall surfaces 175 and 185 have high shape accuracy, and the small clearance is equal to the circumferential wall surface 17.
4, 184 and the circumferential wall surfaces 175, 185 are uniformly secured with high accuracy at any part in the circumferential direction.

(1-2) Rotors 23 to 32 and partition walls 33 to 3
Strict clearance accuracy is required between the opposing end faces between the end faces. For that purpose, the end faces of the partition walls 33 to 37 facing the end faces of the rotors 23 to 32 must have high flatness and high parallelism. End faces 37 of wall pieces 37, 38 constituting partition walls 33, 34 separate from block pieces 17, 18.
It is easy to increase the flatness and parallelism of 2,375,382,385, and the flatness and parallelism of the end faces of the partition walls 33 to 37 are secured with high accuracy.

(1-3) Since the circumferential wall surfaces 174, 184, 175, and 185 of the pump chambers 39 to 43 are formed at one time, the number of processing steps and processing on the circumferential wall surfaces of the pump chambers 39 to 43 are performed. The time is shorter than before. This results in a cost reduction of the multi-stage roots pump 10.

(1-4) The cylinder block 11 has a flat surface S
This is a two-part configuration composed of a pair of block pieces 17 and 18 joined at 1. The configuration in which the cylinder block 11 is divided into two is the simplest in manufacturing the cylinder block 11 including the plurality of pump chambers 39 to 43.

(1-5) The angular range θ1 of the circumferential wall surfaces 174, 184 around the axis 191 of the rotating shaft 19, and the circumferential wall surfaces 175, 18 around the axis 201 of the rotating shaft 20.
The larger the angle range θ2 of 5, the higher the pumping efficiency in the pump chambers 39 to 43. Assembling of the rotors 23 to 32 into the pump chambers 39 to 43 is performed after assembling the block pieces 17 and 18 and the wall pieces 37 and 38 as shown in FIG. The configuration in which the joining surfaces 171 and 181 of the block pieces 17 and 18 are joined on the plane S1 facilitates the incorporation of the rotors 23 to 32 into the pump chambers 39 to 43, and the degree of freedom in setting the shapes of the pump chambers 39 to 43 is increased. Will be the highest. The degree of freedom in setting the shapes of the pump chambers 39 to 43 is as follows.
Pump chambers 39 to 4 in which the angle ranges θ1 and θ2 are increased.
3 can be set. Therefore, the block piece 17,
The configuration in which the bonding surfaces 171 and 181 of the 18 are bonded on the plane S1 facilitates setting of the shapes of the pump chambers 39 to 43 for increasing the pumping efficiency.

(1-6) The straight line L is the rotation axis 1 parallel to each other.
The axis 19 is located at an intermediate position equidistant from the axes 191 and 192 on the plane S1 passing through the axes 191 and 201 of the axes 9 and 20.
It is parallel to 1,201. A pair of block pieces 17, 18
Is symmetrical with respect to the straight line L except for the fluid outlet 173 and the fluid inlet 183, that is, 1
It has a rotational symmetry of 80 °. Such a fluid outlet 173
And the main-shaped block piece 1 excluding the fluid inlet 183
The rough block pieces 47 and 48, which are the bases of Nos. 7 and 18, can be formed by the same mold. Therefore, the symmetry of the main shape of the block pieces 17 and 18 increases the manufacturing efficiency of the block pieces.

(1-7) The partition walls 33 to 37 have a two-part structure composed of a pair of wall pieces 37 and 38 joined at the plane S1. The configuration in which the partitions 33 to 37 are divided into two is the simplest in manufacturing the rotor housing 12 including the plurality of pump chambers 39 to 43.

(1-8) The joint surface 374 of the wall pieces 37, 38
384 are joined at the plane S1 by the insertion holes 49 and 50.
This facilitates the installation of the rotating shafts 191 and 201 into the motor. (1-9) The shape of the pair of wall pieces 37 and 38 is the same, and is symmetrical with respect to the straight line L except for the passages 371 and 381, that is, 180 ° rotationally symmetric about the straight line L. The wall pieces 37 and 38 having such a shape can be formed by the same mold, thereby increasing the production efficiency.

(1-10) The positioning grooves 172 and 182 formed on the inner peripheral wall surface of each of the block pieces 17 and 18 are annular grooves that make a round around the inner peripheral wall surface of the cylinder block 11. It is easy to increase the parallelism of the plurality of positioning grooves 172, 182, and the parallelism of the annular groove formed by the positioning grooves 172, 182 is high. A plurality of positioning grooves 172 with high parallelism
The configuration in which the wall pieces 37 and 38 are fitted into the 182 includes the end faces 372 and 382 and the end faces 37 that form the wall surface of one pump chamber.
The parallelism between 5,385 is increased. Therefore, the end faces 3 of the wall pieces 37 and 38 which are the wall surfaces on which the pump chambers 39 to 43 are formed.
The minute clearance between the rotors 72, 382, 375, 385 and the rotors 23 to 32 can be uniformly secured with high accuracy.

(1-11) The structure in which the wall pieces 37 and 38 constituting the partition walls 33 to 36 are press-fitted into the positioning grooves 172 and 182 is made up of the block pieces 17 and
This is optimal in terms of the ease of assembling the wall pieces 37 and 38 constituting the partition walls 18 with the partition walls 33 to 36.

(1-12) Assembling of the rotors 23 to 32 into the cylinder block 11 is performed while joining the assembled body of the block piece 17 and the wall piece 37 and the assembled body of the block piece 18 and the wall piece 38. Is the most workable. Positioning grooves 172, 182 of block pieces 17, 18
The procedure for assembling the rotors 23 to 32 into the assembled body of the block piece 17 and the wall piece 37 and the assembled body of the block piece 18 and the wall piece 38 after the wall pieces 37 and 38 are pressed into the rotor housing 12 is as follows. Improve the workability of assembly.

Next, a second embodiment shown in FIG. 10 will be described. The same components as those in the first embodiment are denoted by the same reference numerals. In this embodiment, the pin 51 is connected to the joint surfaces 171 and 181 of the block pieces 17 and 18 and the positioning groove 17.
Joining surface 37 of wall pieces 37, 38 fitted in 2,182
It is pressed into the border with 4,384. Positioning groove 17
The wall pieces 37 and 38 fitted into the positioning grooves 182 and 182 are fixed to the positioning grooves 172 and 182 by press-fitting the pins 51. Assembling and fixing the wall pieces 37 and 38 to the block pieces 17 and 18 by press-fitting the pins 51 is also easy.

Next, a third embodiment shown in FIGS. 11 and 12 will be described. The same components as those in the first embodiment are denoted by the same reference numerals. In this embodiment, a cylinder block 53 constituting a rotor housing 52 is constituted by a pair of block pieces 54 and 55 joined on a second plane S2 which is orthogonal to the first plane S1 and passes through a straight line L. I have. The wall pieces 37 and 38 have concave portions 378 and 389 and convex portions 38.
The partition wall is formed by press fitting with 8,379. The wall pieces 37, 38 are fitted into the positioning grooves 541, 551 so that the rotary shafts 19, 20 are inserted therethrough.
Is performed in a state in which

Also in this embodiment, (1-1) to (1-4), (1-6),
The same effects as (1-7) and (1-9) to (1-11) can be obtained.

In the present invention, the following embodiments are also possible. (1) A cylinder block is formed by joining three or more block pieces around the axis of a rotating shaft. (2) In the first embodiment, the positioning grooves 473,
The circumferential wall surface 47 of the rough block pieces 47, 48 without 483
1, 481, 472, 482 are ground and the circumferential wall surface 17
4, 184, and the positioning grooves 172, 1
Grinding 82. (3) The insertion holes 49 and 50 through which the rotating shafts 19 and 20 are inserted are formed after the rotor housing 12 is assembled. (4) In the second embodiment, the positioning grooves 172,
The wall pieces 37 and 38 are fixed to the block pieces 17 and 18 only by the pins 51 without providing the 182. (5) The present invention is applied to a multi-stage roots pump having rotors on three or more rotating shafts.

[0044]

As described above in detail, according to the present invention, the cylinder block forming the peripheral wall surface of the pump chamber and the plurality of partition walls partitioning the adjacent pump chambers are separated from each other, and the cylinder block is formed around the axis of the rotating shaft. A plurality of block pieces are joined in the direction to form the cylinder block, and the plurality of block pieces and the plurality of partition walls are combined to form a rotor housing. In addition, there is an excellent effect that the manufacturing time of the rotor housing can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan sectional view showing a first embodiment.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3A is a sectional view taken along line BB of FIG. 1; (B) is FIG.
CC sectional view taken along the line.

FIG. 4 is a sectional view taken along line DD of FIG. 1;

FIG. 5 is a sectional view taken along line EE of FIG. 1;

FIG. 6 is a perspective view showing a state where a pair of coarse block pieces are joined.

FIG. 7 is a perspective view showing a state before a wall piece 37 is fitted to the block piece 17;

FIG. 8 is a perspective view showing a state before a wall piece 38 is fitted to the block piece 18;

FIG. 9 is a perspective view showing a state in which wall pieces 37 and 38 are assembled to block pieces 17 and 18;

FIG. 10 shows a second embodiment, in which block pieces 17,
The perspective view which shows the state which assembled the wall pieces 37 and 38 to 18.

FIG. 11 is a longitudinal sectional view showing a third embodiment.

FIG. 12 is a longitudinal sectional view.

[Explanation of symbols]

11, 53: cylinder block, 12, 52: rotor housing, 17, 18, 54, 55: block piece, 17
1,181: joining surface, 172, 182: positioning groove, 1
9, 20: rotating shaft, 191, 201: axis, 23 to 23
... rotor, 33-36 ... partition walls, 37, 38 ... wall pieces, 37
4,384: joining surface, 39 to 43: pump chamber, 47,4
8: coarse block piece, S1: (first) plane, S2: (second) plane, L: straight line.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinya Saito 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. Inside Toyota Industries Corporation (72) Inventor Naoki Takahashi 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. F-term in Toyota Industries Corporation (reference) 3H041 AA00 BB09 CC15 DD01 DD05 DD31

Claims (10)

[Claims] 1. A plurality of rotating shafts are arranged in parallel, rotors are arranged on each of the rotating shafts, rotors on adjacent rotating shafts are engaged with each other, and a set of a plurality of rotors engaged with each other is provided. In a multi-stage roots pump formed in the rotor housing so that a plurality of pump chambers are accommodated in the axial direction of the rotating shaft, a cylinder block forming a peripheral wall surface of the pump chamber,
A plurality of partition walls for partitioning adjacent pump chambers are separated from each other, and a plurality of block pieces are joined in a direction around an axis of the rotation shaft to constitute the cylinder block, and the plurality of block pieces and the plurality of block pieces are combined. A multi-stage roots pump comprising the rotor housing in combination with a partition. 2. An axis of the plurality of rotation shafts is on a first plane, and the cylinder block is a second line passing through a straight line at an intermediate position of the plurality of rotation shafts on the first plane.
The multi-stage roots pump according to claim 1, wherein the multi-stage roots pump is constituted by a pair of block pieces joined on a plane. 3. The multi-stage roots pump according to claim 2, wherein the second plane is the same as the first plane. 4. The multi-stage roots pump according to claim 2, wherein said cylinder block is composed of a pair of block pieces having the same peripheral wall shape. 5. The multi-stage roots pump according to claim 2, wherein said partition is constituted by a pair of wall pieces joined on a second plane passing through said straight line. 6. The positioning device according to claim 1, wherein a plurality of positioning grooves are formed in parallel on an inner wall surface of said plurality of block pieces, and said partition wall is fitted in said positioning groove. The multi-stage roots pump according to the above. 7. The multi-stage roots pump according to claim 6, wherein said partition is press-fitted into said positioning groove. 8. A plurality of rotating shafts are arranged in parallel, rotors are arranged on each of the rotating shafts, rotors on adjacent rotating shafts are engaged with each other, and one set of a plurality of rotors engaged with each other is provided. In a method for manufacturing a rotor housing of a multi-stage roots pump formed in a rotor housing so that a plurality of pump chambers are accommodated in the axial direction of the rotary shaft, a cylinder block forming a peripheral wall surface of the pump chamber is constituted. And a method of manufacturing a rotor housing of a multi-stage roots pump in which a plurality of rough block pieces are temporarily joined to each other, and the peripheral wall surfaces of the plurality of pump chambers are formed by grinding while holding the joined pieces. 9. A method for manufacturing a rotor housing for a multi-stage roots pump according to claim 8, wherein a positioning groove for fitting a plurality of partitions for partitioning adjacent pump chambers is formed before or after the peripheral wall surface is ground. . 10. The multi-stage roots pump according to claim 9, wherein after the peripheral wall surface is ground and after the positioning groove is formed, a wall piece constituting the partition is pressed into the positioning groove of each block piece. How to make rotor housing.