Pump mounting structure

Abstract

A housing 2 of a pump has an insertion hole 31 into which a bolt 40 is inserted, and a protruding part 22 formed so as to protrude. A body 102 to be mounted has a fastening hole 50 which is formed corresponding to the insertion hole 31 of the housing 2 and to which the bolt 40 is fastened, and an insertion hole 52 into which the protruding part 22 of the housing 2 is inserted. A mounting structure 100 includes a collar 41 which is provided to protrude from one among the insertion hole 31 and the fastening hole 50 and into which the bolt 40 is inserted, and a fitting hole 53 which is provided to the other among the insertion hole 31 and the fastening hole 50 and into which the collar 41 is fitted.

Description

Pump mounting structure

[0001] The present invention relates to a pump mounting structure.

[0002] Japanese Patent Application Laid-Open Publication No. 2021-4604 discloses an electric pump device mounting structure including an electric pump device and a mounting surface to which the electric pump device is mounted. In this mounting structure, a positioning portion of the electric pump device fits into a positioning portion of the mounting surface of the mounting surface, thereby ensuring the mounting accuracy of the electric pump device to the mounting surface.

[0003] In JP 2021-4604 A, the positioning portion of the electric pump device is a pin portion that is fixed by press-fitting into a hole formed in the end face of the flange portion. Therefore, special processing is required for the hole into which the pin portion is press-fit, which increases the processing time. As a result, the manufacturing cost of the electric pump increases.

[0004] An object of the present invention is to improve the mounting accuracy of a pump to a mounting body at low cost.

[0005] According to one aspect of the present invention, there is provided an attachment structure for attaching a pump housing to a mounting body, wherein the housing has an insertion hole through which a fastening member is inserted, and a protruding portion formed to protrude and having an inlet port for directing liquid to the pump or an outlet port for directing liquid discharged from the pump; the mounting body has a fastening hole formed to correspond to the insertion hole of the housing and through which the fastening member is fastened, and an insertion hole into which the protruding portion of the housing is inserted; and the attachment structure comprises a cylindrical portion protruding from one of the insertion hole and the fastening hole and through which the fastening member is inserted, and a fitting hole formed in the other of the insertion hole and the fastening hole and into which the cylindrical portion fits.

[0006] FIG. 1 is a side view of an electric pump and a mounting body according to an embodiment of the present invention, where the mounting body is shown in cross section. FIG. 2 is a perspective view of an electric pump according to an embodiment of the present invention. FIG. 3 is a plan view of an electric pump according to an embodiment of the present invention. FIG. 4 is a cross-sectional view of a mounting structure according to an embodiment of the present invention, showing a state in which fastening members are not fastened. FIG. 5 is a cross-sectional view of a mounting structure according to an embodiment of the present invention, showing a state in which fastening members are fastened. FIG. 6 is a plan view of an electric pump according to an embodiment of the present invention, where the arrangement of insertion holes is different from the form shown in FIG. 3. FIG. 7 is a side view of an electric pump and a mounting body according to a modified embodiment of the present invention, where the mounting body is shown in cross section.

[0007] Hereinafter, a mounting structure 100 for mounting an electric pump 101 to a mounting target body 102 according to an embodiment of the present invention will be described with reference to the drawings.

[0008] The electric pump 101 is mounted on, for example, a vehicle and discharges a coolant (liquid) for cooling an electric motor mounted on the vehicle or discharges oil (liquid) for lubricating gears mounted on the vehicle. The electric pump 101 may also be used as a fluid pressure supply source that discharges a working fluid (liquid) for driving equipment. The electric pump 101 may also be mounted on industrial machinery other than a vehicle.

[0009] First, the electric pump 101 and the mounting body 102 will be described with reference to Figures 1 to 3. Figure 1 is a side view of the electric pump 101 mounted on the mounting body 102, with the mounting body 102 shown in cross section. Figure 2 is a perspective view of the electric pump 101 alone. Figure 3 is a plan view of the electric pump 101 alone, as viewed from the side indicated by arrow A in Figure 1.

[0010] As shown in FIGS. 1 to 3 , the electric pump 101 has a housing 2 that houses a pump section and a motor section that are connected via a drive shaft 1 (see FIG. 3 ). The housing 2 also houses a controller that controls the operation of the motor section. In this manner, the electric pump 101 is a unit in which the pump section, the motor section, and the controller are housed within the housing 2. The drive shaft 1 is rotatably supported by the housing 2 via bearings. In this embodiment, the pump section is an internal gear pump that has an inner rotor connected to the drive shaft 1 and an outer rotor disposed outside the inner rotor. The configuration of an internal gear pump is similar to a well-known configuration, so a detailed description will be omitted. Note that the pump section is not limited to an internal gear pump, and may be a vane pump or other pump.

[0011] The housing 2 has a main body 10 and a protrusion 22 formed to protrude from the main body 10. In the following description, the axial direction of the drive shaft 1 will also be simply referred to as the "axial direction."

[0012] The main body 10 has a rectangular portion 11 with a rectangular outer periphery, a circular portion 12 formed integrally with the rectangular portion 11 and with a circular outer periphery, and a cover portion 20 attached to the circular portion 12 via bolts 3 as fastening members and sealing the opening of the circular portion 12. A pump portion is housed in a first circular portion 12a on the distal end side of the circular portion 12, and a motor portion is housed in a second circular portion 12b on the proximal end side of the circular portion 12. A controller is housed within the rectangular portion 11. The cover portion 20 has an outer diameter identical to that of the circular portion 12 and is attached to the end face of the circular portion 12. A protrusion 22 is formed to protrude from the cover portion 20 of the main body 10. The protrusion 22 protrudes parallel to the axial direction of the drive shaft 1, and the central axis O of the protrusion 22 is offset from the central axis of the drive shaft 1.

[0013] A suction port 21a (see FIG. 3) for introducing liquid into the pump section is provided on the surface of the cover section 20. A discharge port 22a (see FIG. 3) for introducing liquid discharged from the pump section to the outside is provided on the tip surface of the protrusion 22.

[0014] In the main body 10, the dimension of the rectangular portion 11 in the direction perpendicular to the drive shaft 1 is larger than the outer diameter of the circular portion 12. Therefore, the rectangular portion 11 has an end face 11a that extends radially from the outer circumferential surface of the circular portion 12. The end face 11a abuts against an end face 102a of the mounting body 102, thereby determining the axial position of the electric pump 101 relative to the mounting body 102.

[0015] A plurality of flanges 30 are formed on the outer peripheral surface of the rectangular portion 11. End faces 30a of the flanges 30 and end faces 11a of the rectangular portion 11 are formed as a continuous surface. The flanges 30 are formed with insertion holes 31 through which bolts 40 serving as fastening members for fixing the electric pump 101 to the mounting body 102 are inserted.

[0016] The mounting body 102 is a case of a device that uses the liquid discharged from the electric pump 101. The device is, for example, a transmission or a transaxle device.

[0017] 1, the mount 102 is formed to correspond to the insertion hole 31 of the housing 2 of the electric pump 101, and has a fastening hole 50 (see FIG. 4) into which the bolt 40 is fastened, an accommodating recess 51 that accommodates a portion of the housing 2, and an insertion hole 52 formed in the bottom surface of the accommodating recess 51 and into which the protrusion 22 of the housing 2 is inserted. The fastening hole 50 and the accommodating recess 51 are formed to open on an end surface 102a of the mount 102. An internal thread is formed on the inner peripheral surface of the fastening hole 50, into which the external thread of the bolt 40 is threaded.

[0018] When attaching the electric pump 101 to the attachment target 102, the circular portion 12 of the housing 2 of the electric pump 101 is accommodated in the accommodation recess 51 of the attachment target 102, and the end face 11a of the rectangular portion 11 of the housing 2 is abutted against the end face 102a of the attachment target 102 while the protrusion 22 of the housing 2 is inserted into the insertion hole 52 of the attachment target 102. Then, the bolt 40 is inserted into the insertion hole 31 of the housing 2 and fastened to the fastening hole 50 of the attachment target 102, thereby pressing the end face 30a of the flange 30 and the end face 11a of the rectangular portion 11 of the housing 2 against the end face 102a of the attachment target 102, and attaching the electric pump 101 to the attachment target 102. When the electric pump 101 is attached to the attachment target 102, the space between the housing 2 and the bottom surface of the accommodation recess 51 of the attachment target 102, specifically the space between the cover part 20 and the bottom surface of the accommodation recess 51, becomes the storage part 4 in which the liquid is stored. The storage part 4 is faced by the suction port 21a provided on the surface of the cover part 20.

[0019] When the electric pump 101 is attached to the object to be attached 102 and the motor part of the electric pump 101 is driven, the pump part of the electric pump 101 draws liquid from the storage part 4 through the suction port 21a, discharges the pressurized liquid, and guides it into the insertion hole 52 of the object to be attached 102 through the discharge port 22a.

[0020] A small gap exists between the outer peripheral surface of the circular portion 12 of the housing 2 and the inner peripheral surface of the accommodating recess 51. There is also a small gap between the outer peripheral surface of the protruding portion 22 of the housing 2 and the inner peripheral surface of the insertion hole 52. An O-ring 5 is provided on the outer peripheral surface of the protruding portion 22 as a sealing member. The O-ring 5 is compressed between the outer peripheral surface of the protruding portion 22 and the inner peripheral surface of the insertion hole 52, sealing the gap between the two. Therefore, liquid guided to the insertion hole 52 through the discharge port 22a of the protruding portion 22 is prevented from leaking into the accommodating recess 51 through the gap between the protruding portion 22 and the insertion hole 52, and is supplied to the equipment through the insertion hole 52. In other words, the O-ring 5 prevents communication between the discharge side and the suction side of the pump unit, thereby preventing a decrease in the performance of the pump unit. An O-ring (not shown) is also provided between the end face 11a of the rectangular portion 11 of the housing 2 and the end face 102a of the mounting body 102 as a sealing member to seal the gap between the two.

[0021] Here, when the electric pump 101 is fixed to the mounting body 102 using only the bolts 40, gaps exist between the outer peripheral surface of the circular portion 12 of the housing 2 and the inner peripheral surface of the accommodating recess 51, and between the outer peripheral surface of the protruding portion 22 of the housing 2 and the inner peripheral surface of the insertion hole 52, so there is a risk that the central axis O of the protruding portion 22 may be misaligned with the central axis of the insertion hole 52 when inserted into the insertion hole 52. In this case, the compression amount of the O-ring 5 will not be uniform in the circumferential direction, and the sealing performance of the O-ring 5 will be impaired.

[0022] Therefore, in this embodiment, in order to improve the mounting accuracy of the electric pump 101 to the mounting base 102, that is, to improve the positioning accuracy of the protrusion 22 relative to the insertion hole 52, the mounting structure 100 for mounting the electric pump 101 to the mounting base 102 includes the following configuration in addition to the bolt 40. The mounting structure 100 will be described in detail below, mainly with reference to Figures 3 to 5. Figure 4 is a cross-sectional view of the mounting structure 100, showing a state in which the bolt 40 is not fastened. Figure 5 is a cross-sectional view of the mounting structure, showing a state in which the bolt 40 is fastened.

[0023] A press-fit hole 32 having an inner diameter larger than the inner diameter of the insertion hole 31 is formed at the opening of the insertion hole 31 formed in the flange 30 of the housing 2. A collar 41 serving as a cylindrical portion is press-fitted into the press-fit hole 32. In other words, the inner diameter of the press-fit hole 32 and the outer diameter of the collar 41 are approximately the same.

[0024] The inner diameter of the collar 41 is approximately the same as the inner diameter of the insertion hole 31. Therefore, the bolt 40 can be inserted through the hollow portion of the collar 41 (see FIG. 5). The length (axial length) of the collar 41 is greater than the depth of the press-fit hole 32. Therefore, when the collar 41 is press-fitted into the press-fit hole 32 and the end face of the collar 41 abuts against the bottom surface of the press-fit hole 32 (the state shown in FIG. 4), a portion of the collar 41 protrudes from the insertion hole 31. In other words, a portion of the collar 41 protrudes from the end face 30a of the flange 30.

[0025] A fitting hole 53 having an inner diameter larger than the inner diameter of the fastening hole 50 is formed at the opening of the fastening hole 50 formed in the attached body 102 corresponding to the insertion hole 31. A part of the collar 41 (the part protruding from the insertion hole 31) fits into the fitting hole 53. The inner diameter of the fitting hole 53 is approximately the same as the inner diameter of the press-fit hole 32. Therefore, the housing 2 is positioned relative to the attached body 102 by the collar 41 provided across the press-fit hole 32 and the fitting hole 53.

[0026] When the collar 41 is fitted into the fitting hole 53 (the state shown in FIG. 4 ), a gap exists between the end face of the collar 41 and the bottom surface of the fitting hole 53. In other words, the length of the collar 41 is smaller than the sum of the depths of the press-fit hole 32 and the fitting hole 53. Therefore, when the collar 41 is provided across the press-fit hole 32 and the fitting hole 53, a gap is prevented from occurring between the end face 11 a of the rectangular portion 11 of the housing 2 and the end face 102 a of the mounted body 102. Therefore, when the bolt 40 is threaded into the fastening hole 50, the axial force of the bolt 40 presses the end face 30 a of the flange 30 and the end face 11 a of the rectangular portion 11 of the housing 2 against the end face 102 a of the mounted body 102.

[0027] The press-fit hole 32 and the fitting hole 53 are formed in the insertion hole 31 and the fastening hole 50, respectively, to which the bolt 40 is attached. Therefore, the press-fit hole 32 and the fitting hole 53 can be machined together with the insertion hole 31 and the fastening hole 50, thereby reducing the number of machining steps. Furthermore, compared to machining the press-fit hole 32 and the fitting hole 53 in locations different from the insertion hole 31 and the fastening hole 50, machining accuracy can be improved.

[0028] When attaching the electric pump 101 to the mounting base 102, the collar 41 is press-fit into the press-fit hole 32 in advance. Then, when inserting the protruding portion 22 of the housing 2 into the insertion hole 52 of the mounting base 102 while accommodating the circular portion 12 of the housing 2 in the accommodating recess 51 of the mounting base 102, the collar 41 is fitted into the fitting hole 53 of the mounting base 102 (the state shown in FIG. 4 ). Attaching the electric pump 101 to the mounting base 102 via the collar 41 improves the mounting accuracy of the electric pump 101 to the mounting base 102, thereby improving the positioning accuracy of the protruding portion 22 with respect to the insertion hole 52. As a result, the central axis O of the protruding portion 22 coincides with the central axis of the insertion hole 52, and the compression amount of the O-ring 5 is uniform in the circumferential direction, resulting in good sealing performance of the O-ring 5. After the electric pump 101 is attached to the mounting body 102 via the collar 41 , the electric pump 101 is fixed to the mounting body 102 using the bolts 40 .

[0029] Next, the position where the collar 41 is provided will be described with reference to Figures 3 and 6. Figure 6 shows a different embodiment from that shown in Figure 3, and the arrangement of the insertion holes 31 is different from that shown in Figure 3.

[0030] In this embodiment, flanges 30 are formed on three of the four side surfaces of the rectangular portion 11, and the electric pump 101 is fixed to the mounting body 102 by three bolts 40. That is, in this embodiment, three corresponding insertion holes 31 and fastening holes 50 are formed. Three insertion holes 31a, 31b, and 31c are shown in Figures 3 and 6.

[0031] By providing collars 41 in all three insertion holes 31a, 31b, 31c, the mounting accuracy of the electric pump 101 to the mounting base 102 is improved, but the number of steps required to process the press-fit holes 32 and the fitting holes 53 increases accordingly. Therefore, in order to reduce the number of steps required to process the press-fit holes 32 and the fitting holes 53, it is preferable to provide collars 41 and fitting holes 53 in some of the corresponding multiple insertion holes 31 and fastening holes 50. Two collars 41 are sufficient to determine the mounting position of the electric pump 101 to the mounting base 102, so it is preferable to provide collars 41 in at least two insertion holes 31.

[0032] However, even if the collar 41 is provided in only one insertion hole 31, the mounting accuracy of the electric pump 101 to the mounting body 102 is improved, so a configuration in which only one collar 41 is provided may be adopted.

[0033] When determining which of the multiple corresponding insertion holes 31 and fastening holes 50 to provide the collar 41 and fitting hole 53, it is preferable to select the insertion hole 31 and fastening hole 50 that are longest from the central axis O of the protrusion 22. This is because the longer the distance between the collar 41 and the central axis O of the protrusion 22, the greater the effect of reducing vibration of the electric pump 101 relative to the attached body 102. In Figure 3, the insertion hole 31a that is longest from the central axis O of the protrusion 22 and the fastening hole 50 corresponding thereto are selected as the one to provide the collar 41 and fitting hole 53.

[0034] When determining which two of the three or more corresponding insertion holes 31 and fastening holes 50 will be provided with the collar 41 and the fitting hole 53, it is preferable to select two that maximize the area of ​​an imaginary triangle whose vertices are the central axis O of the protrusion 22 and the centers of the two insertion holes 31. This is because the larger the area of ​​the imaginary triangle, the greater the effect of reducing vibration of the electric pump 101 relative to the attached body 102. In the embodiment shown in FIG. 3 , as indicated by the two-dot chain lines, there are three imaginary triangles: an imaginary triangle T1 whose vertices are the central axis O of the protrusion 22 and the centers of the two insertion holes 31 a, 31 b; an imaginary triangle T2 whose vertices are the central axis O of the protrusion 22 and the centers of the two insertion holes 31 a, 31 c; and an imaginary triangle T3 whose vertices are the central axis O of the protrusion 22 and the centers of the two insertion holes 31 b, 31 c. Of these, the imaginary triangle T1 has the largest area. 3, the insertion holes 31a, 31b and the corresponding fastening holes 50 are selected as the two holes for providing the collar 41 and the fitting hole 53. Note that the imaginary triangles T1, T2, and T3 are drawn on a plan view of the electric pump 101 as seen in the axial direction of the drive shaft 1, as shown in FIG.

[0035] Furthermore, when determining two of the three or more corresponding insertion holes 31 and fastening holes 50 in which to provide the collar 41 and the fitting hole 53, it is preferable that the angle formed by the line segment connecting the central axis O of the protrusion 22 and the centers of the two insertion holes 31 (the angle of the vertex of the central axis O of the protrusion 22 in the imaginary triangle, which is the angle α1, α2, and α3 shown in FIG. 6 ) be close to 60°. In other words, it is preferable to select two of the insertion holes 31 and fastening holes 50 such that the imaginary triangle having the vertices of the central axis O of the protrusion 22 and the centers of the two insertion holes 31 is closest to an equilateral triangle. In the embodiment shown in FIG. 6 , as indicated by the two-dot chain lines, there are three imaginary triangles: an imaginary triangle T1 having the vertices of the central axis O of the protrusion 22 and the centers of the two insertion holes 31 a, 31 b; an imaginary triangle T2 having the vertices of the central axis O of the protrusion 22 and the centers of the two insertion holes 31 a, 31 c; and an imaginary triangle T3 having the vertices of the central axis O of the protrusion 22 and the centers of the two insertion holes 31 b, 31 c. The imaginary triangle T2 is flattened, with the angle α2 of the vertex of the central axis O of the protrusion 22 being close to 180°, and the protrusion 22 and the two insertion holes 31a, 31c being aligned in a substantially straight line. In this case, the electric pump 101 is more likely to vibrate in the rotational direction around the protrusion 22 relative to the mounting body 102. The imaginary triangle T3 is also flattened, with the angle α3 being close to 180°. On the other hand, the imaginary triangle T1 is closest to an equilateral triangle, with the angle α1 of the vertex of the central axis O of the protrusion 22 being closest to 60°. Therefore, in the embodiment shown in FIG. 6 , the insertion holes 31a, 31b and the corresponding fastening holes 50 are selected as the two for providing the collar 41 and the fitting hole 53.

[0036] In this embodiment, the pump unit is an internal gear pump that sucks in liquid through the suction port 6 and discharges liquid through the discharge port 7 during one rotation. The suction port 6 is formed as an arc-shaped opening on the back surface of the cover unit 20 and communicates with the suction port 21a. The discharge port 7 is formed as an arc-shaped opening on the back surface of the cover unit 20 and communicates with the discharge port 22a. As such, the pump unit, which is an internal gear pump, performs one suction and one discharge per rotation. Therefore, the pump unit is divided into an suction side region 8 and a discharge side region 9 by a boundary line D that passes through the center of the drive shaft 1 and the midpoint C of the suction port 6 and the discharge port 7 in the rotational direction of the drive shaft 1. Therefore, a pressure difference occurs across the boundary line D in the pump unit, which is likely to cause vibrations in the vertical direction of the pages in Figures 3 and 6 due to the pressure difference. For this reason, when determining two of the three or more corresponding insertion holes 31 and fastening holes 50 in which to provide the collar 41 and fitting hole 53, it is preferable to select the two that sandwich the boundary line D. By providing the collar 41 on either side of the boundary line D, it is possible to reduce vibration of the electric pump 101 relative to the attached body 102. In the embodiment shown in Figures 3 and 6, the insertion holes 31a, 31b and the corresponding fastening holes 50 that are provided on either side of the boundary line D are selected as the two in which to provide the collar 41 and fitting hole 53.

[0037] In the above, three methods have been described for determining two of the three or more corresponding insertion holes 31 and fastening holes 50 in which to provide the collars 41 and fitting holes 53: two in which the area of ​​an imaginary triangle having vertices formed by the central axis O of the protrusion 22 and the centers of the two insertion holes 31 is largest, two in which the imaginary triangle having vertices formed by the central axis O of the protrusion 22 and the centers of the two insertion holes 31 is closest to an equilateral triangle, and two in which the boundary line D is sandwiched between the two. The two in which to provide the collars 41 and fitting holes 53 may be determined so as to satisfy all three or two of the three.

[0038] According to the above embodiment, the following advantageous effects are achieved.

[0039] The through-hole 31 through which the bolt 40 is inserted is provided with the press-fit hole 32 into which the collar 41 is press-fitted, and the fastening hole 50 into which the bolt 40 is fastened is provided with the fitting hole 53 into which the collar 41 is fitted. This allows the press-fit hole 32 and the fitting hole 53 to be machined together with the through-hole 31 and the fastening hole 50. In other words, the through-hole 31 and the press-fit hole 32 can be machined in the same machining process, and the fastening hole 50 and the fitting hole 53 can be machined in the same machining process. This reduces the number of machining steps, thereby improving the mounting accuracy of the electric pump 101 to the mounting body 102 at low cost.

[0040] Furthermore, compared to machining a positioning pin and its insertion hole at a position separate from the insertion hole 31 and the fastening hole 50, machining the insertion hole 31 and the press-fit hole 32 in the same machining process, and machining the fastening hole 50 and the fitting hole 53 in the same machining process, improves the machining accuracy of the press-fit hole 32 and the fitting hole 53. As a result, the mounting accuracy of the electric pump 101 to the mounting body 102 is improved.

[0041] Furthermore, when a collar 41 and a fitting hole 53 are provided in some of the multiple corresponding insertion holes 31 and fastening holes 50, the vibration of the electric pump 101 relative to the mounting body 102 can be reduced by appropriately selecting the insertion holes 31 and fastening holes 50 in which the collar 41 and the fitting hole 53 are provided.

[0042] Modifications of the above embodiment will be described below. The following modifications are also within the scope of the present invention, and it is possible to combine the following modifications with the configuration of the above embodiment, or to combine the following modifications with each other.

[0043] (1) In the above embodiment, the electric pump 101 has been described as an example of the object to be attached to the attachment base 102. However, the object to be attached to the attachment base 102 is not limited to the electric pump 101 and may simply be a pump. In this case, only the pump unit is housed within the housing 2, and the drive shaft 1 is rotatably supported by the housing 2. In other words, the motor unit and the controller are not housed within the housing 2.

[0044] (2) In the above embodiment, the electric pump 101 is fixed to the mounting base 102 by three bolts 40. However, the number of bolts 40 that fix the electric pump 101 to the mounting base 102 is not limited to three and may be one, two, four or more. When there is one bolt 40, a collar 41 and a fitting hole 53 are provided in the insertion hole 31 and the fastening hole 50 to which the bolt 40 is attached.

[0045] (3) In the above embodiment, the collar 41 is press-fitted into the press-fit hole 32 formed in the insertion hole 31, and a portion of the collar 41 protrudes from the insertion hole 31. In other words, the collar 41 is a separate member from the flange 30 in which the insertion hole 31 is formed. Alternatively, the press-fit hole 32 may not be formed in the insertion hole 31, and the collar 41 and the flange 30 may be formed integrally. In other words, as long as a cylindrical portion protruding from the insertion hole 31 is provided, the cylindrical portion may be a separate member from the flange 30 or may be integral with the flange 30.

[0046] (4) In the above embodiment, the collar 41 is press-fitted into the press-fit hole 32 formed in the insertion hole 31 of the electric pump 101, and the collar 41 is fitted into the fitting hole 53 formed in the fastening hole 50 of the mount base 102. Alternatively, a press-fit hole into which the collar 41 is press-fitted may be formed in the fastening hole 50 of the mount base 102, and a fitting hole into which the collar 41 is fitted may be formed in the insertion hole 31 of the electric pump 101. In this embodiment, the fastening hole 50 may not be formed with a press-fit hole, and the collar 41 and the mount base 102 may be formed integrally. In other words, as long as a cylindrical portion protruding from the fastening hole 50 is provided, the cylindrical portion may be either a separate member from the mount base 102 or integral with the mount base 102. In this manner, the mounting structure 100 includes a cylindrical portion protruding from one of the insertion hole 31 and the fastening hole 50, and a fitting hole formed in the other of the insertion hole 31 and the fastening hole 50 into which the cylindrical portion is fitted.

[0047] (5) In the above embodiment, the discharge port 22a is provided on the tip surface of the protrusion 22 of the cover part 20. Alternatively, a suction port may be provided on the tip surface of the protrusion 22 of the cover part 20. In this case, the discharge port is provided on the surface of the cover part 20. In this way, the protrusion 22 of the cover part 20 is provided with a discharge port that guides liquid discharged from the pump part or a suction port that guides liquid to the pump part.

[0048] (6) In the above embodiment, the mounting base 102 has an accommodation recess 51 that accommodates a portion of the housing 2 of the electric pump 101, and an insertion hole 52 formed in the bottom surface of the accommodation recess 51 and into which the protrusion 22 of the housing 2 is inserted. However, the accommodation recess 51 is not an essential component of the present invention. In this case, as shown in FIG. 7 , the accommodation recess 51 is not formed in the end surface 102a of the mounting base 102, and the insertion hole 52 is formed in the end surface 102a of the mounting base 102. Furthermore, the suction port 21a that introduces liquid to the pump section communicates with a suction port (not shown) formed in the end surface 102a of the mounting base 102. The flange 30 is formed on the outer peripheral surface of the circular portion 12, not on the outer peripheral surface of the rectangular portion 11.

[0049] (7) The cross section of the collar 41 as a cylindrical portion may not be a perfect circle, but may be an arc shape with a partially open section (for example, a C-shape).

[0050] The configuration, operation, and effects of the embodiment of the present invention will be described below.

[0051] This embodiment is a mounting structure 100 for mounting a housing 2 of a pump (electric pump 101) to a mounting base 102. The housing 2 has an insertion hole 31 through which a fastening member (bolt 40) is inserted, and a protrusion 22 formed on the housing 2 and provided with an inlet 21a for introducing liquid into the pump or an outlet 22a for introducing liquid discharged from the pump. The mounting base 102 has a fastening hole 50 formed corresponding to the insertion hole 31 of the housing 2 and into which the fastening member (bolt 40) is fastened, and an insertion hole 52 into which the protrusion 22 of the housing 2 is inserted. The mounting structure 100 includes a cylindrical portion (collar 41) protruding from one of the insertion hole 31 and the fastening hole 50 and through which the fastening member (bolt 40) is inserted, and a fitting hole 53 formed on the other of the insertion hole 31 and the fastening hole 50 into which the cylindrical portion (collar 41) fits.

[0052] In this configuration, a cylindrical portion is provided on one of the insertion hole 31 through which the fastening member (bolt 40) is inserted and the fastening hole 50 into which the fastening member (bolt 40) is fastened, and a fitting hole 53 into which the cylindrical portion fits is provided on the other, so that the machining of the cylindrical portion and the fitting hole 53 can be performed simultaneously with the machining of the insertion hole 31 and the fastening hole 50. Therefore, the mounting accuracy of the pump (electric pump 101) to the mounting target body 102 can be improved at low cost.

[0053] The cylindrical portion (collar 41 ) is press-fitted into a press-fit hole 32 formed in one of the insertion hole 31 and the fastening hole 50 and having an inner diameter substantially the same as the inner diameter of the fitting hole 53 .

[0054] In this configuration, the press-fit holes 32 and the fitting holes 53 can be machined at the same time as the insertion holes 31 and the fastening holes 50. Therefore, the mounting accuracy of the pump (electric pump 101) to the mounting target body 102 can be improved at low cost.

[0055] In addition, a plurality of corresponding insertion holes 31 and fastening holes 50 are provided, and the cylindrical portion (collar 41) and the fitting hole 53 are provided in some of the plurality of corresponding insertion holes 31 and fastening holes 50.

[0056] In this configuration, the number of steps required to process the cylindrical portion (collar 41) and the fitting hole 53 can be reduced.

[0057] In addition, three or more corresponding insertion holes 31 and fastening holes 50 are provided, and of the three or more corresponding insertion holes 31 and fastening holes 50, the cylindrical portion (collar 41) and the fitting hole 53 are provided in the two that form the largest area of ​​a virtual triangle with the protrusion 22 and the two insertion holes 31 as vertices.

[0058] In addition, three or more corresponding insertion holes 31 and fastening holes 50 are provided, and of the three or more corresponding insertion holes 31 and fastening holes 50, the cylindrical portion (collar 41) and the fitting hole 53 are provided in the two holes such that the imaginary triangle with the protrusion 22 and the two insertion holes 31 as vertices is closest to an equilateral triangle.

[0059] In addition, three or more corresponding insertion holes 31 and fastening holes 50 are provided, and of the three or more corresponding insertion holes 31 and fastening holes 50, the cylindrical portions (collars 41) and fitting holes 53 are provided in only two of them, which are on either side of an imaginary line D that passes through the center of the drive shaft 1 and divides the pump section into a discharge side region and a suction side region.

[0060] These configurations can reduce the number of steps required for processing the cylindrical portion (collar 41) and the fitting hole 53, and can also reduce vibration of the pump (electric pump 101) relative to the mounting body 102.

[0061] 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.

[0062] This application claims priority based on Japanese Patent Application No. 2023-51958, filed with the Japan Patent Office on March 28, 2023, the entire contents of which are incorporated herein by reference.

Claims

1. A mounting structure for mounting a pump housing to a mounting object, comprising: The housing includes: an insertion hole through which a fastening member is inserted; a protruding portion provided with a suction port for introducing liquid into the pump or a discharge port for introducing liquid discharged from the pump, The object to be attached is a fastening hole formed in the housing corresponding to the insertion hole, into which the fastening member is fastened; an insertion hole into which the protrusion of the housing is inserted; The mounting structure includes: a cylindrical portion provided to protrude from one of the insertion hole and the fastening hole, and through which the fastening member is inserted; a fitting hole provided in the other of the insertion hole and the fastening hole, into which the cylindrical portion fits; Three or more of the insertion holes and the fastening holes corresponding to each other are provided, A pump mounting structure in which the cylindrical portion and the fitting hole are provided in the two of three or more corresponding insertion holes and fastening holes that form the largest area of ​​an imaginary triangle with the protrusion and the two insertion holes as vertices.

2. A mounting structure for mounting a pump housing to a mounting object, comprising: The housing includes: an insertion hole through which a fastening member is inserted; a protruding portion provided with a suction port for introducing liquid into the pump or a discharge port for introducing liquid discharged from the pump, The object to be attached is a fastening hole formed in the housing corresponding to the insertion hole, into which the fastening member is fastened; an insertion hole into which the protrusion of the housing is inserted; The mounting structure includes: a cylindrical portion provided to protrude from one of the insertion hole and the fastening hole, and through which the fastening member is inserted; a fitting hole provided in the other of the insertion hole and the fastening hole, into which the cylindrical portion fits; Three or more of the insertion holes and the fastening holes corresponding to each other are provided, A pump mounting structure in which, among three or more corresponding insertion holes and fastening holes, the cylindrical portion and the fitting hole are provided in the two holes such that an imaginary triangle with the protrusion and the two insertion holes as vertices is closest to an equilateral triangle.

3. A mounting structure for mounting a pump housing to a mounting body, comprising: The housing includes: an insertion hole through which a fastening member is inserted; a protruding portion provided with a suction port for introducing liquid into the pump or a discharge port for introducing liquid discharged from the pump, The object to be attached is a fastening hole formed in the housing corresponding to the insertion hole, into which the fastening member is fastened; an insertion hole into which the protrusion of the housing is inserted; The mounting structure includes: a cylindrical portion provided to protrude from one of the insertion hole and the fastening hole, and through which the fastening member is inserted; a fitting hole provided in the other of the insertion hole and the fastening hole, into which the cylindrical portion fits; Three or more of the insertion holes and the fastening holes corresponding to each other are provided, Of the three or more corresponding insertion holes and fastening holes, the cylindrical portion and the fitting hole are provided in two that pass through the center of the drive shaft of the pump and are on either side of an imaginary line that divides the pump into a discharge side region and a suction side region.

4. The pump mounting structure according to any one of claims 1 to 3, The cylindrical portion is press-fitted into a press-fit hole formed in one of the insertion hole and the fastening hole and having an inner diameter substantially the same as the inner diameter of the fitting hole.

5. The pump mounting structure according to any one of claims 1 to 3, a plurality of the insertion holes and the fastening holes corresponding to each other are provided, The cylindrical portion and the fitting hole are provided in some of a plurality of corresponding insertion holes and fastening holes.