Method for manufacturing rotary machine

Abstract

This method for manufacturing a pump 1 involves: using bolt fastening places A1 and A3 among a plurality of bolt fastening places A as a plurality of positioning fastening places A1 and A3 formed in such a manner that a positioning hole B2 between a body 3 and a pump cover 4 also serves as a bolt insertion hole; inserting a positioning pin P into the positioning hole B2 in the plurality of positioning fastening places A1 and A3; positioning the pump cover 4 on the body 3; bolt-fastening bolt fastening places A other than the plurality of positioning fastening places A1 and A3 in a state in which the pump cover 4 is positioned on the body 3 by the positioning pin P; removing the positioning pin P; and bolt-fastening the plurality of positioning fastening places A1 and A3.

Description

Manufacturing method of a rotating machine

[0001] The present invention relates to a method for manufacturing a rotating machine.

[0002] JPH10-68389A discloses a gear pump having a case, a cover bolted to the case, a shaft rotatably supported by the case and the cover via bushings, and a knock pin engaging with the case and the cover.

[0003] Using knock pins to position the cover increases the cost of the parts, requires a process for pressing the knock pins, and requires space for installing pin holes for the knock pins.

[0004] The present invention has been made in view of the above problems, and aims to improve positioning.

[0005] According to one aspect of the present invention, there is provided a method for manufacturing a rotating machine having a housing, a cover that is positioned on and bolted to the housing, and a shaft that is supported rotatably from the housing to the cover, wherein the housing and cover have three or more bolt fastening points, wherein at least two of the bolt fastening points are multiple positioning and fastening points formed by positioning holes in the housing and cover that also serve as bolt insertion holes, and positioning pins are inserted into the positioning holes at the multiple positioning and fastening points to position the cover on the housing, and with the cover positioned on the housing by the positioning pin, bolt fastening points other than the multiple positioning and fastening points, and the positioning pin is removed and the multiple positioning and fastening points are bolt fastened.

[0006] Fig. 1 is a side view of a pump according to an embodiment of the present invention, Fig. 2 is a plan view of the pump according to an embodiment of the present invention, and Fig. 3 is an explanatory diagram of a method for manufacturing the pump.

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0008] FIG. 1 is a side view of a pump 1. The pump 1 is a rotating machine, a hydraulic rotating machine that pressurizes and discharges hydraulic oil as a working fluid. The pump 1 is driven by a drive source such as an engine or an electric motor. Various pumps that suck in hydraulic oil stored in a tank, increase the pressure of the sucked hydraulic oil, and discharge the oil can be used as the pump 1, such as a vane pump, a piston pump, or a gear pump. In this embodiment, a case where the pump 1 is a vane pump will be described.

[0009] The pump 1 includes a pump mechanism 2, a body 3 that houses the pump mechanism 2, and a pump cover 4 that closes an opening of the body 3. The pump mechanism 2 includes a drive shaft 2s to which power from a drive source is transmitted, a rotor 2r that is connected to the drive shaft 2s and is driven to rotate by the power of the drive source, a plurality of vanes 2v that are provided so as to be able to reciprocate radially relative to the rotor 2r, and a cam ring 2c that houses the rotor 2r and has an inner cam surface against which the tips of the vanes 2v slide as the rotor 2r rotates.

[0010] The body 3 has an accommodation recess 3a that accommodates the pump mechanism 2. The accommodation recess 3a accommodates a cam ring 2c that accommodates a rotor 2r and vanes 2v. The body 3 and pump cover 4 have insertion holes 3b, 4a for a drive shaft 2s, and the drive shaft 2s is inserted in this order through the insertion hole 4a of the pump cover 4, the rotor 2r, and the insertion hole 3b of the body 3, and is connected to the rotor 2r. The body 3 corresponds to a housing.

[0011] The drive shaft 2s is a shaft that is rotatably supported from the body 3 to the pump cover 4. The drive shaft 2s is rotatably supported by the body 3 via a bush 5 provided in the insertion hole 3b, and is rotatably supported by the pump cover 4 via a bush 6 provided in the insertion hole 4a.

[0012] A sealing member (not shown) is provided between the insertion hole 4a of the pump cover 4 and the drive shaft 2s, closer to the tip of the drive shaft 2s (upper side in FIG. 1) than the bushing 6. The drive shaft 2s may be supported directly by the body 3 or the pump cover 4 without the bushing 5 or the bushing 6.

[0013] Two arcuate suction ports 4b, 4c that open to correspond to the suction regions of the cam ring 2c are formed in the surface of the pump cover 4 on which the rotor 2r slides. Inside the cam ring 2c, multiple pump chambers (not shown) are formed by the outer peripheral surface of the rotor 2r, the inner peripheral cam surfaces of the cam ring 2c, and adjacent vanes 2v. The suction ports 4b, 4c are connected to a tank (not shown) via a tank passage, and hydraulic oil is introduced into the pump chambers through the suction ports 4b, 4c.

[0014] The pump mechanism 2 draws hydraulic oil into a pump chamber as the rotor 2r rotates, increases the pressure of the drawn hydraulic oil, and discharges it into a high-pressure chamber 3c. The high-pressure chamber 3c is formed in an annular shape at the bottom of the accommodation recess 3a, and is connected to a fluid pressure device (e.g., a power steering device, a transmission, etc.) (not shown) outside the pump 1 via a discharge passage (not shown).

[0015] A pump cover 4 is disposed in contact with one side surface (upper side in FIG. 1) of the rotor 2r and cam ring 2c of the pump mechanism 2, and a side plate 7 is disposed in contact with the other side surface (lower side in FIG. 1). The pump cover 4 and side plate 7 are disposed with both sides of the rotor 2r and cam ring 2c sandwiched between them, sealing the pump chamber. One side surface of the rotor 2r is in sliding contact with the pump cover 4, and one side surface of the cam ring 2c is in contact with the pump cover 4. The side plate 7 is provided between the bottom of the installation recess 3a and the rotor 2r, and the other side surface of the rotor 2r is in sliding contact with the side plate 7, and the other side surface of the cam ring 2c is in contact with the side plate 7.

[0016] Two discharge ports 7a, 7b that guide hydraulic oil from the pump chamber to the high-pressure chamber 3c are formed in the side plate 7. The discharge ports 7a, 7b have an arc-shaped opening that corresponds to the discharge area of ​​the cam ring 2c, and discharge the hydraulic oil discharged from the pump chamber to the high-pressure chamber 3c.

[0017] Two positioning pins (not shown) are provided on the pump cover 4, the cam ring 2c, and the side plate 7. The positioning pins restrict the relative rotation of the pump cover 4 and the side plate 7 with respect to the cam ring 2c, and determine the positions of the suction area of ​​the cam ring 2c and the suction ports 4b, 4c of the pump cover 4, and the discharge area of ​​the cam ring 2c and the discharge ports 7a, 7b of the side plate 7.

[0018] The side plate 7, rotor 2r, and cam ring 2c are housed in the housing recess 3a. In this state, the housing recess 3a is sealed by attaching the pump cover 4 to the body 3 with bolts 8. The pump 1 has a plurality of bolt fastening points A, as will be described next.

[0019] Figure 2 is a plan view of the pump 1. As shown in Figure 2, the pump 1 has a total of four bolt fastening points A, namely, bolt fastening points A1 to A4. The bolt fastening points A are points where the body 3 and the pump cover 4 are fastened by bolts, and at each bolt fastening point A, a bolt 8 is inserted through the pump cover 4 and tightened to the body 3, thereby fastening the pump cover 4 to the body 3 with the bolts.

[0020] The two bolt fastening points A1 and A3 are disposed opposite each other across the drive shaft 2s. Therefore, the two bolt fastening points A1 and A3 are disposed at opposing positions. The distance (linear distance) between the bolt fastening points A1 and A3 is longer than the distance between the bolt fastening points A1 and A2 and the distance between the bolt fastening points A1 and A4. The bolt fastening points A1 and A3 are used as positioning fastening points, as will be described below with reference to FIG. 3.

[0021] 3A and 3B are explanatory diagrams of a manufacturing method of the pump 1. In FIG. 3A and 3B, an assembly process of the pump cover 4 will be described, which includes three steps, a first step to a third step, shown in order from the top in FIG.

[0022] First, the bolt fastening point A will be further described. The bolt fastening points A2 and A4 (see the second step in the center of Figure 3) have a bolt insertion hole B1 and a threaded hole C. The bolt insertion hole B1 is formed in the body 3 and the pump cover 4. The bolt insertion hole B1 is a normal bolt insertion hole and is formed by a cast hole. Therefore, the bolt insertion hole B1 does not have the high machining precision required for a positioning hole. The threaded hole C has a female thread formed therein, into which the bolt 8 is fastened. Note that the bolt insertion hole B1 may be formed only in the pump cover 4.

[0023] The bolt fastening points A1 and A3 have a positioning hole B2 and a threaded hole C. That is, the bolt fastening points A1 and A3 differ from the bolt fastening points A2 and A4 in that they have a positioning hole B2 instead of a bolt insertion hole B1. Note that, for ease of explanation, the diameter of the positioning hole B2 is exaggerated in Figure 3 compared to the bolt insertion hole B1.

[0024] The positioning holes B2 are used to position the body 3 and the pump cover 4, and are machined with high precision for positioning. The bolt fastening points A1 and A3 where the positioning holes B2 are formed are formed as multiple positioning fastening points where the positioning holes B2 also serve as bolt insertion holes. Hereinafter, the bolt fastening points A1 and A3 will also be referred to as the positioning fastening points A1 and A3.

[0025] Next, the process of assembling the pump cover 4 will be described. The pump cover 4 is assembled to the body 3 using an assembly device (not shown). The assembly device is an automated assembly device that includes a cover setting device that supplies and sets the pump cover 4 to the body 3, a positioning device that performs positioning using positioning pins P (see the second step in the center of Figure 3), and a screw driver that can tighten bolts at multiple bolt fastening locations A.

[0026] The screw driver includes a screw driver main body that fastens the bolts, a moving device such as a robot that moves the screw driver main body to a predetermined bolt fastening location A and sets it in place, and a bolt supply device that supplies bolts 8 to the screw driver main body. The screw driver may be of a single-axis configuration or a multi-axis configuration.

[0027] In the first step, the cover setting device sets the pump cover 4 on the body 3. In the first step, by setting the pump cover 4 on the body 3, the position of the pump cover 4 relative to the body 3 is roughly adjusted.

[0028] In the second step, a positioning device positions the pump cover 4 on the body 3 using the positioning pins P. The positioning pins P are installed in the positioning device as positioning jigs. In other words, the positioning pins P are not components of the pump 1. Therefore, the pump 1 does not require positioning pins for positioning the pump cover 4 on the body 3, thereby reducing parts costs.

[0029] A plurality of positioning pins P (two in this example) are provided corresponding to the positioning and fastening points A1 and A3. Each positioning pin P is movable between a positioning position and a retracted position (not shown) by a positioning device, and is also movable in the vertical direction. The positioning position is the position of the positioning pin P corresponding to the positioning and fastening points A1 and A3, and the retracted position is a retracted position from the positioning and fastening points A1 and A3. The retracted position constitutes the fixed position of the positioning pin P in the assembly device.

[0030] Therefore, in the second step, each of the two positioning pins P moves from its retracted position to its positioning position and descends toward the corresponding positioning hole B2. As a result, the positioning pins P are inserted into the positioning holes B2 at multiple positioning and fastening points A1, A3, and the pump cover 4 is positioned on the body 3. The pump cover 4 is positioned on the body 3 at two points.

[0031] With the pump cover 4 positioned on the body 3 by the positioning pins P as described above, in the second step the screwdriver main body, which was in its fixed position, is set to the bolt fastening points A2 and A4 by the moving device. In addition, bolts 8 are supplied to the screwdriver main body from the bolt supply device, and the screwdriver main body tightens the supplied bolts 8 to fasten the bolt fastening points A2 and A4.

[0032] As a result, with the pump cover 4 positioned on the body 3 by the positioning pin P, the bolt fastening points A other than the multiple positioning and fastening points A1 and A3 (i.e., bolt fastening points A2 and A4) are bolted. In the case of a single-axis screw driving machine, the bolt fastening points A2 and A4 can be bolted by sequentially fastening the bolts at the screw driving machine main body. In the case of a multi-axis screw driving machine, the bolt fastening points A2 and A4 can be bolted simultaneously at the screw driving machine main body.

[0033] As described above with reference to FIG. 2, the two positioning fastening points A1 and A3 are disposed opposite each other with the drive shaft 2s therebetween, and are thus disposed at a large radial distance from each other.

[0034] Therefore, when the pump cover 4 is positioned on the body 3 in the second step and the bolt fastening points A2 and A4 are fastened with bolts, even if the pump cover 4 shifts within the range of play at the positioning fastening points A1 and A3, the positional shift of the pump cover 4 can be suppressed.

[0035] Furthermore, by suppressing the displacement of the pump cover 4 as described above, it is possible to suppress leakage of hydraulic oil and deterioration of pulsation when the port timing is determined by the suction ports 4b and 4c. The suction ports 4b and 4c correspond to flow paths.

[0036] In the third step, the positioning device removes the positioning pin P, and then the screw driver tightens bolts at the multiple positioning and fastening points A1, A3. For example, after bolt tightening at the bolt fastening points A2, A4 is completed, the positioning pin P is raised by the positioning device while the screw driver body remains seated on at least one of the bolt fastening points A2, A4. In this case, when the positioning pin P is removed from the positioning hole B2, the screw driver body can hold the product (the pump 1 under manufacture), preventing the product from being lifted by the positioning pin P. The positioning pin P may be raised by a method different from that described above.

[0037] The raised positioning pin P is moved to the retracted position by the positioning device, and after the positioning pin P has moved to the retracted position, the screw fastener body is set at the positioning and fastening points A1 and A3 by the moving device. This prevents interference between the screw fastener and the positioning pin P.

[0038] By tightening the bolts at the bolt tightening points A2 and A4 in the second step, the pump cover 4 is already positioned and fixed to the body 3 in the third step. Therefore, in the third step, the screw tightening tool main body set at the positioning and fastening points A1 and A3 can tighten the bolts 8 as is, thereby performing the bolt tightening without causing misalignment of the pump cover 4. After completing tightening at the positioning and fastening points A1 and A3, the screw tightening tool main body returns to its fixed position, thereby completing the series of automatic cycles of the assembly device.

[0039] In the pump 1, by positioning and bolting the pump cover 4 to the body 3 in this manner, tilting of the drive shaft 2s supported by the body 3 and the pump cover 4 is prevented, and deterioration of vibration and noise of the pump 1 is suppressed.

[0040] As described above, in the pump 1, the two positioning fastening points A1 and A3 are disposed opposite each other with the drive shaft 2s therebetween, and are thus disposed in a dispersed manner in the circumferential direction.

[0041] For this reason, the positioning hole B2 does not necessarily have to have a larger diameter than the normal bolt insertion hole B1, but even if a positioning hole B2 with a larger diameter reduces the bolt seating surface and reduces the axial force of the bolt 8 to some extent, it is possible to prevent the imbalance of the axial force. Also, at the two positioning fastening points A1, A3, the axial force can be increased by increasing the fastening length between the bolt 8 and the threaded hole C, but by distributing them as described above, it becomes possible to use a common bolt 8 at multiple bolt fastening points A.

[0042] Note that part or all of the manufacturing method of the pump 1 embodied by the assembly device may be performed by a person. Furthermore, the manufacturing method of the pump 1 may be applied to rotating machines other than the pump 1, such as motors. The plurality of bolt fastening points A may be three or more bolt fastening points A, and the plurality of positioning fastening points A1, A3 may be some of the plurality of bolt fastening points A, and may be at least two of them.

[0043] The configuration, operation, and effects of the embodiment of the present invention will be described below.

[0044] A manufacturing method for a pump (1) includes a body (3), a pump cover (4) that is positioned on and bolted to the body (3), and a drive shaft (2s) that is supported rotatably from the body (3) to the pump cover (4), and the body (3) and pump cover (4) have a plurality of bolt fastening points (A), and bolt fastening points (A1, A3) among the plurality of bolt fastening points (A) are formed as a plurality of positioning fastening points (A1, A3) formed by positioning holes (B2) in the body (3) and pump cover (4) that also serve as bolt insertion holes, and positioning pins (P) are inserted into the positioning holes (B2) at the plurality of positioning fastening points (A1, A3) to position the pump cover (4) on the body (3), and with the pump cover (4) positioned on the body (3) by the positioning pins (P), bolt fastening points (A) other than the plurality of positioning fastening points (A1, A3) are performed, and the positioning pins (P) are removed and the plurality of positioning fastening points (A1, A3) are bolted.

[0045] According to this configuration, the positioning pin P is used as a jig for positioning, and the pump 1 does not need to include the positioning pin P, thereby reducing costs. Furthermore, the positioning pin P as a jig is removed after being inserted into the positioning hole B2, eliminating the need for a press-fitting process. Furthermore, because the positioning hole B2 is integrated with the bolt insertion hole, there is no need to reserve space for installing the positioning hole B2. Therefore, a positioning configuration that is advantageous in terms of cost, manufacturing, and space can be obtained, and positioning can be improved.

[0046] The plurality of positioning fastening points A1, A3 includes two positioning fastening points A1, A3 arranged opposite to each other across the drive shaft 2s. Note that in this embodiment, the plurality of positioning fastening points A1, A3 are two positioning fastening points A1, A3.

[0047] According to this configuration, the two positioning and fastening points A1, A3 are disposed dispersedly in the circumferential direction, so that the imbalance of the axial force of the bolt 8 can be suppressed.

[0048] The pump 1 is a hydraulic rotary machine, and the pump cover 4 is formed with suction ports 4b and 4c as flow paths.

[0049] According to this configuration, the positioning pin P prevents the pump cover 4 from shifting out of position, so that leakage of hydraulic oil and deterioration of pulsation can be prevented when determining port timing at the suction ports 4b and 4c.

[0050] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments.

[0051] This application claims priority based on Japanese Patent Application No. 2024-45157, filed with the Japan Patent Office on March 21, 2024, the entire contents of which are incorporated herein by reference.

Claims

1. A manufacturing method for a rotating machine having a housing, a cover that is positioned on and bolted to the housing, and a shaft that is supported rotatably from the housing to the cover, wherein the housing and the cover have three or more bolt fastening points, wherein at least two of the bolt fastening points are multiple positioning fastening points formed by positioning holes in the housing and the cover that also serve as bolt insertion holes, positioning pins are inserted into the positioning holes at the multiple positioning fastening points to position the cover on the housing, with the cover positioned on the housing by the positioning pins, bolting the bolt fastening points other than the multiple positioning fastening points, and removing the positioning pins and bolting the multiple positioning fastening points.

2. A method for manufacturing a rotating machine according to claim 1, wherein the plurality of positioning and fastening points include two positioning and fastening points arranged opposite each other with the shaft in between.

3. A method for manufacturing a rotating machine according to claim 2, wherein the rotating machine is a hydraulic rotating machine, and a flow path is formed in the cover.

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