Automotive cooling component and method for producing the automotive cooling component

Abstract

To provide an automotive cooling component that reduces residual burr particles therein, and to provide a method for producing the automotive cooling component.SOLUTION: An automotive cooling component has a case and a cover. The case has a case welded part formed along a peripheral edge of a case opening. The cover has a cover opening that faces the case opening. The cover has a cover welded part formed along a peripheral edge of the cover opening. A direction along a central axis is defined as a first direction, and a direction orthogonal to the central axis is defined as a second direction. Either one of the case welded part and the cover welded part is defined as a first welded part, and the other is defined as a second welded part. At a tip of the first welded part in the first direction, an inclined surface is formed so as to slope away from the second welded part from the inner side to the outer side in the second direction. At a tip of the second welded part in the first direction, a plane intersecting the first direction is formed. The first welded part and the second welded part are joined together by welding.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to automotive cooling components and methods for manufacturing automotive cooling components. [Background technology]

[0002] Electric water pumps and other cooling components for automobiles are used to circulate coolant between the engine and the radiator. Pumps such as electric water pumps have a case and a cover. The case houses the pump's components. The cover covers the opening of the case. The case and cover are made of a resin material and are joined by vibration welding. Friction during vibration welding generates powder burrs. There is a demand for automotive cooling components that are less likely to leave powder burrs inside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6891565 Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by the present disclosure is to provide an automotive cooling part in which powder burrs are less likely to remain inside, and a method for manufacturing an automotive cooling part. [Means for solving the problem]

[0005] In order to solve the above problems, the present disclosure employs the following aspects. (1) An automotive cooling component according to one aspect of the present disclosure includes a case and a cover. The case has a case opening at an end in a first direction along a central axis. The case accommodates components of the automotive cooling component inside in a second direction perpendicular to the central axis. The case has a case weld along the periphery of the case opening. The covers are arranged side by side in the first direction of the case. The cover has a cover opening facing the case opening. The cover has a cover weld along the periphery of the cover opening. One of the case weld and the cover weld is a first weld, and the other is a second weld. In this case, a sloped surface is formed at the tip of the first weld in the first direction, sloping away from the second weld from the inside to the outside in the second direction. A flat surface intersecting the first direction is formed at the tip of the second weld in the first direction. The first weld and the second weld are joined by welding.

[0006] Because an inclined surface is formed at the tip of the first welded portion, the contact area between the first welded portion and the second welded portion is smaller, resulting in greater surface pressure. The temperature of the contact portion rises quickly due to frictional heat between the first welded portion and the second welded portion. The rubbing at the contact portion ends in a short time, and the contact portion melts quickly. This suppresses the generation of powder burrs due to rubbing at the contact portion. The inclined surface of the first welded portion abuts against the second welded portion sequentially, starting from the inside in the second direction. The inside in the second direction of the portion where powder burrs are generated is already melted. The generated powder burrs are less likely to scatter toward the inside in the second direction. This makes it less likely that powder burrs will remain inside the automotive cooling part.

[0007] (2) In the automotive cooling component of the above aspect (1), the volume of the outer weld burr extending outward in the second direction from the weld layer between the first weld portion and the second weld portion is smaller than the volume of the inner weld burr extending inward in the second direction from the weld layer. Since an inclined surface is formed at the tip of the first weld, the volume of the molten region of the first weld decreases from the inside to the outside in the second direction, and therefore the volume of the outer weld burr generated by melting the molten region is smaller than the volume of the inner weld burr.

[0008] (3) In the automotive cooling component described in (1) or (2) above, the automotive cooling component has an inner standing wall and an outer standing wall. The inner standing wall is arranged spaced apart inward in the second direction from the first welded portion and the second welded portion. The outer standing wall is arranged spaced apart outward in the second direction from the first welded portion and the second welded portion. The inner standing wall prevents inner welding burrs from flowing into the inside of the automotive cooling component, and the outer standing wall prevents outer welding burrs from flowing out of the automotive cooling component.

[0009] (4) A manufacturing method for an automotive cooling part according to one aspect of the present disclosure is a manufacturing method for an automotive cooling part having a case and a cover. The case has a case opening at an end in a first direction along a central axis. The case houses components of the automotive cooling part on the inside in a second direction perpendicular to the central axis. The case has a case weld along the periphery of the case opening. The covers are arranged side by side in the first direction of the cases. The cover has a cover opening facing the case opening. The cover has a cover weld along the periphery of the cover opening. One of the case weld and the cover weld is a first weld, and the other is a second weld. An inclined surface is formed at the tip of the first weld in the first direction, sloping away from the second weld from the inside to the outside in the second direction, and a flat surface is formed at the tip of the second weld in the first direction, intersecting the first direction, and the first weld and the second weld are joined by welding.

[0010] Because an inclined surface is formed at the tip of the first welded portion, the contact area between the first welded portion and the second welded portion is smaller, resulting in greater surface pressure. The temperature of the contact portion rises quickly due to frictional heat between the first welded portion and the second welded portion. The rubbing at the contact portion ends in a short time, and the contact portion melts quickly. This suppresses the generation of powder burrs due to rubbing at the contact portion. The inclined surface of the first welded portion abuts against the second welded portion sequentially, starting from the inside in the second direction. The inside in the second direction of the portion where powder burrs are generated is already melted. The generated powder burrs are less likely to scatter toward the inside in the second direction. This makes it less likely that powder burrs will remain inside the automotive cooling part.

[0011] (5) In the manufacturing method of an automotive cooling part described in (4) above, a plane intersecting the first direction is formed on the inside of the inclined surface at the tip of the first direction of the first welded portion in the second direction, and the first welded portion and the second welded portion are joined by welding. The flat surface of the first welded portion abuts against the second welded portion, thereby preventing damage to the tip of the first welded portion.

[0012] (6) In the method for manufacturing an automotive cooling component according to (4) or (5), a region of the first welded portion that melts due to welding is defined as a melted region, and the height of the inclined surface in the first direction is smaller than the height of the melted region in the first direction. The fusion zone has a distal end zone with an inclined surface and a proximal end zone without an inclined surface. In the proximal end zone without an inclined surface, welding is performed with low surface pressure at the contact points. At this time, welding between the first and second welded portions progresses slowly, resulting in a thicker welded layer. This prevents a decrease in welding strength.

[0013] (7) In the method for manufacturing an automotive cooling component according to any one of (4) to (6) above, the width of the second welded portion in the second direction is larger than the width of the first welded portion in the second direction. As a result, welding is performed while maintaining contact between the tip of the first welded portion, on which the inclined surface is formed, and the second welded portion. [Effects of the Invention]

[0014] The present disclosure makes it possible to provide an automotive cooling part in which powder burrs are less likely to remain inside, and a method for manufacturing an automotive cooling part. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 2 is a cross-sectional view of a pump according to an embodiment. [Figure 2] FIG. 4 is a cross-sectional view of a case welded portion and a cover welded portion. [Figure 3] FIG. 3 is a first explanatory diagram of a method for manufacturing a pump according to an embodiment. [Figure 4] FIG. 6 is a second explanatory diagram of the method for manufacturing the pump according to the embodiment. [Figure 5] Graph showing changes in each part due to vibration welding. [Figure 6] 10 is a graph showing the relationship between the inclination angle of the inclined surface and the weight of powder burrs remaining inside the pump. [Figure 7] 10 is a graph showing the relationship between the inclination angle of the inclined surface and the burst strength of the pump. DETAILED DESCRIPTION OF THE INVENTION

[0016] An automotive cooling component and a manufacturing method thereof according to an embodiment will be described below with reference to the drawings. The automotive cooling component according to the embodiment is, for example, a pump such as an electric water pump that circulates coolant between an engine and a radiator of an automobile. 1 is a cross-sectional view of a pump 1 according to an embodiment. The pump 1 draws in a fluid through a suction port 23 and discharges the fluid through a discharge port 24. The pump 1 is formed in a substantially cylindrical shape.

[0017] In this application, the Z direction and R direction of the cylindrical coordinate system are defined as follows. The Z direction (first direction) is the direction along the central axis C of the pump 1. The +Z direction is the direction in which the cover 20 is disposed as viewed from the case 30, and the -Z direction is the direction in which the cap 10 is disposed as viewed from the case 30. The R direction (second direction) is a direction perpendicular to the Z direction and is the radial direction of the pump 1. The +R direction is a direction away from the central axis C of the pump 1, and the -R direction is a direction approaching the central axis C of the pump 1. The +R direction is sometimes called the outside of the R direction, and the -R direction is sometimes called the inside of the R direction.

[0018] The pump 1 has a case 30, a cover 20, and a cap 10. The case 30, the cover 20, and the cap 10 are made of a thermoplastic resin material such as polyphenylene sulfide (PPS). The cap 10 may be made of a metal material such as aluminum.

[0019] Case 30 accommodates the components of pump 1 inside in the R direction. Case 30 has a case first opening (case opening) 31 at the end in the +Z direction and a case second opening 32 at the end in the -Z direction. The cover 20 is arranged next to the case 30 in the +Z direction and covers the case first opening 31. The cover 20 has a cover opening 21 at the end in the -Z direction. The cover opening 21 faces the case first opening 31. The cover 20 is formed with a suction port 23 and a discharge port 24 for a fluid. The cap 10 is arranged next to the case 30 in the −Z direction and covers the case second opening 32. The cap 10 is detachable from the case 30.

[0020] The pump 1 includes a shaft 2 , a motor 4 , a control board 15 , and an impeller 8 . The shaft 2 is disposed coaxially with the central axis C. The −Z direction end of the shaft 2 is supported by the case 30, and the +Z direction end is supported by the cover 20. The motor 4 has a rotor 5 and a stator 6. The rotor 5 is disposed around the shaft 2 and is rotatable. The stator 6 is disposed around the rotor 5 and is supported by a case 30.

[0021] The control board 15 is disposed in the −Z direction of the case 30 and is housed inside the cap 10. The control board 15 controls the operation of the motor 4. Impeller 8 is fixed in the +Z direction of rotor 5. Impeller 8 is housed inside cover 20. Inlet port 23 of cover 20 opens in the +Z direction of impeller 8. Outlet port 24 of cover 20 opens in the tangential direction of the outer periphery of impeller 8. The rotor 5 of the motor 4 is rotated under the control of the control board 15. The impeller 8 rotates together with the rotor 5, and the fluid is sucked in through the suction port 23 and discharged from the discharge port 24.

[0022] 2 is an enlarged view of part P in FIG. 1, and is a cross-sectional view of cover welded portion 25 and case welded portion 35. Cover 20 has cover welded portion 25, and case 30 has case welded portion 35.

[0023] Cover weld 25 is formed along the periphery of cover opening 21. Cover weld 25 is approximately annular when viewed from the -Z direction. Cover weld 25 protrudes in the -Z direction. The ±R direction side surfaces of cover weld 25 are tapered surfaces that are slightly inclined with respect to the Z direction. A tip surface 27 of cover weld 25 in the -Z direction is a plane that intersects with the Z direction. Tip surface 27 may also be a plane that is perpendicular to the Z direction.

[0024] Case weld 35 is formed along the periphery of first case opening 31. Case weld 35 is approximately annular when viewed from the +Z direction. Case weld 35 protrudes in the +Z direction. The ±R direction side surfaces of case weld 35 are tapered surfaces that are slightly inclined with respect to the Z direction. R direction width 35r of case weld 35 is smaller than R direction width 25r of cover weld 25. The +Z direction end of case weld 35 is melted region 38. Vibration welding, which will be described later, melts melted region 38, joining case weld 35 and cover weld 25.

[0025] A flat surface 37 and an inclined surface 36 are formed at the tip of case weld 35 in the +Z direction. Flat surface 37 is formed on the inside of the R direction (-R direction). Flat surface 37 intersects with the Z direction. Flat surface 37 may be perpendicular to the Z direction. For example, width 37r of flat surface 37 in the R direction is approximately one-third of width 35r of case weld 35. Inclined surface 36 is formed on the outside of the R direction (+R direction). Inclined surface 36 inclines away from cover weld 25 from the inside to the outside in the R direction. In the example of FIG. 2, inclined surface 36 is flat. Inclined surface 36 is inclined at an inclination angle θ with respect to flat surface 37.

[0026] The height 38z of the melted region 38 in the Z direction decreases from the inside to the outside in the R direction due to the presence of the inclined surface 36. The volume of the melted region 38 per unit length in the R direction decreases from the inside to the outside in the R direction. The height 36z of the inclined surface 36 in the Z direction is smaller than the height 38z of the melting region 38 in the Z direction. For example, the height 36z of the inclined surface 36 is approximately half the height 38z of the melting region 38. As a result, the width in the R direction of the lower half of the melting region 38 in the -Z direction is the same as the width 35r of the case weld portion 35.

[0027] Pump 1 has an inner space 41s and an outer space 42s. Inner space 41s is formed in the -R direction of case welded portion 35 and cover welded portion 25. Outer space 42s is formed in the +R direction of case welded portion 35 and cover welded portion 25. As shown in FIG. 1 , the peripheries of inner space 41s and outer space 42s are covered by case 30 and cover 20.

[0028] The -R direction of the inner space 41s is covered by an inner standing wall 41w. The inner standing wall 41w is disposed at a distance in the -R direction from the case welding portion 35 and the cover welding portion 25. The inner standing wall 41w protrudes from the case 30 in the +Z direction, but may protrude from the cover 20 in the -Z direction.

[0029] The +R direction of outer space 42s is covered by outer standing wall 42w. Outer standing wall 42w is disposed at a distance in the +R direction from case weld portion 35 and cover weld portion 25. Outer standing wall 42w protrudes from cover 20 in the -Z direction, but may protrude from case 30 in the +Z direction.

[0030] A method for manufacturing pump 1 of this embodiment, including vibration welding of case weld portion 35 and cover weld portion 25, will be described. Fig. 3 is a first explanatory diagram of a manufacturing method of pump 1 in this embodiment, and Fig. 4 is a second explanatory diagram. First, the components of pump 1 are housed inside case 30. Cover 20 is arranged in the +Z direction of case 30.

[0031] Case weld 35 and cover weld 25 are vibration-welded together. Specifically, as shown in FIG. 3 , flat surface 37 of case weld 35 abuts against tip surface 27 of cover weld 25. The abutment of flat surface 37 of case weld 35 reduces damage to the tip of case weld 35 compared to when flat surface 37 is not present at the tip of case weld 35. Cover 20 is vibrated linearly in the R direction. Vibrating cover 20 prevents vibration of the pump components housed inside case 30. Case 30 is pressed in the +Z direction toward cover 20. The abutting portion between case weld 35 and cover weld 25 melts due to frictional heat. Cover 20 moves in the -Z direction by an amount corresponding to height 38z of melted region 38 in case weld 35.

[0032] Vibration welding causes case weld 35 and cover weld 25 to thermally melt. As described above with reference to FIG. 2, R-direction width 35r of case weld 35 is smaller than R-direction width 25r of cover weld 25. Heat from case weld 35 is less likely to escape to the surroundings than from cover weld 25. Therefore, case weld 35 melts preferentially.

[0033] Figure 4 shows the state after vibration welding is completed. Melting of melting area 38 of case weld 35 forms a weld layer 40 between case weld 35 and cover weld 25. Weld layer 40 joins case weld 35 and cover weld 25. The thickness of weld layer 40 in the Z direction is smaller than height 38z of melting area 38 (see Figure 3). Melting of melting area 38 creates inner and outer weld burrs 41 and 42. Inner weld burr 41 extends from weld layer 40 in the -R direction, and outer weld burr 42 extends from weld layer 40 in the +R direction.

[0034] The inner weld burr 41 is accommodated in the inner space 41s, and the outer weld burr 42 is accommodated in the outer space 42s. An inner standing wall 41w (see FIG. 1) that covers the -R direction of the inner space 41s prevents the inner weld burr 41 from flowing into the inside of the pump 1. An outer standing wall 42w (see FIG. 1) that covers the +R direction of the outer space 42s prevents the outer weld burr 42 from flowing out of the pump 1.

[0035] As described above with reference to Figure 2, an inclined surface 36 is formed at the tip of case weld 35. Inclined surface 36 slopes away from cover weld 25 from the inside to the outside in the R direction. The volume of melted region 38 per unit length in the R direction decreases from the inside to the outside in the R direction. Therefore, the volume of outer weld burr 42 generated by melting of melted region 38 is smaller than the volume of inner weld burr 41.

[0036] Vibration welding generates powder burrs in addition to welding burrs. The mechanism by which powder burrs are generated will be explained with reference to Figure 5. Figure 5 is a graph showing the changes in each part due to vibration welding. The horizontal axis of Figure 5 represents time, and the vertical axis represents temperature and thickness. Vibration welding has a vibration process and a pressure holding process. The vibration process has a friction region I, a transition region II, and a steady state region III. The pressure holding process has a solidification region IV.

[0037] In friction region I, the temperature of the resin material that makes up both case weld portion 35 and cover weld portion 25 rises due to friction between them. When the temperature of the resin material exceeds the melting temperature, transition region II begins. In the transition region II, the resin material exceeds its glass transition point and softens and deforms. In the transition region II, the amount of melting in the melting region 38 and the thickness of the welding layer 40 increase. In the steady state region III, the melting of the resin material progresses, and the melting amount increases in the melted region 38. In the steady state region III, the thickness of the weld layer 40 does not increase, and an inner weld burr 41 and an outer weld burr 42 occur. In the solidification region IV, the deposition layer 40 cools and solidifies.

[0038] In friction area I, the case welded portion 35 and the cover welded portion 25 rub against each other, generating powder burrs of the resin material. The generated powder burrs scatter inside and outside of pump 1. Powder burrs remaining inside pump 1 may affect the performance and durability of pump 1. A pump and a method for manufacturing a pump that is less likely to generate powder burrs inside is needed.

[0039] As described above, an inclined surface 36 is formed at the tip of the case welding portion 35. At the start of vibration welding, only the flat surface 37 of the case welding portion 35 abuts against the tip surface 27 of the cover welding portion 25. In the abutting portion between the two, the friction region I starts. Since the contact area of the abutting portion is small and the surface pressure is large, the temperature of the resin material rises rapidly. When the temperature of the resin material exceeds the melting temperature, the transition region II starts in the abutting portion. By forming the inclined surface 36 at the tip of the case welding portion 35, the transition region II starts rapidly in the abutting portion. In the transition region II, since the resin material softens and melts, powder burrs do not occur. Thereby, the generation of powder burrs is suppressed.

[0040] The tip of the case welding portion 35 melts and the cover welding portion 25 moves in the -Z direction. The inclined surface 36 is inclined so as to separate from the cover welding portion 25 from the inner side to the outer side in the R direction. The inclined surface 36 abuts against the tip surface 27 of the cover welding portion 25 in order from the inner side in the R direction. In the inclined surface 36, the friction region I starts in order from the inner side in the R direction, and powder burrs are generated. However, inside the R direction of the portion where the friction region I has started on the inclined surface 36, the resin material has already melted. Therefore, the generated powder burrs are unlikely to scatter to the inner side in the R direction. Most of the powder burrs generated on the inclined surface 36 scatter to the outer side in the R direction. Thereby, it is difficult for powder burrs to remain inside the pump 1.

[0041] FIG. 6 is a graph showing the relationship between the inclination angle θ of the inclined surface 36 and the weight of the powder burrs remaining inside the pump 1. The horizontal axis in FIG. 6 is the inclination angle θ of the inclined surface 36 shown in FIG. 2. The cases where θ is A deg and B deg (A < B) are examples, and the case where θ is 0 deg is a comparative example. In the comparative example where θ is 0 deg, only the flat surface 37 is formed at the tip of the case welding portion 35, and the inclined surface 36 is not formed. The vertical axis in FIG. 6 is the weight of the powder burrs remaining inside the pump 1. The powder burrs remaining inside the pump 1 were collected from the cleaning liquid used to clean the inside of the pump 1 and weighed.

[0042] Compared to the comparative example where θ is 0°, the weight of powder burrs remaining inside pump 1 is smaller in the examples where θ is Adeg and Bdeg. In the examples, it is thought that the scattering of powder burrs inward in the R direction is suppressed by the case welded part 35 having inclined surface 36. When θ is Bdeg, the weight of powder burrs remaining inside pump 1 is smaller than when θ is Adeg. When θ is Bdeg, inclined surface 36 of case welded part 35 gradually abuts against cover welded part 25. Therefore, it is thought that the surface pressure is always high at the abutting point between the two, and transition region II begins quickly.

[0043] As described above, in vibration welding, the case 30 is pressed in the +Z direction toward the cover 20. Increasing this pressure is thought to increase the surface pressure at the contact point between the case weld 35 and the cover weld 25. However, it is known that increasing the pressure causes the two to weld more quickly, thinning the weld layer 40 and reducing the weld strength. If the weld strength decreases, there is a possibility that the weld layer 40 will break (burst) if the internal pressure of the pump 1 increases.

[0044] In this embodiment, an inclined surface 36 is formed at the tip of case weld portion 35. This increases the surface pressure at the contact point between case weld portion 35 and cover weld portion 25 without increasing the pressure, which allows transition region II to begin quickly and suppresses the generation of powder burrs.

[0045] As described above with reference to FIG. 2, the height 36z of the inclined surface 36 in the Z direction is smaller than the height 38z of the melting region 38 in the Z direction. In the tip region 38a of the melting region 38 in the +Z direction where the inclined surface 36 exists, vibration welding is performed with high surface pressure at the contact portion. In contrast, in the base region 38b of the melting region 38 in the -Z direction where the inclined surface 36 does not exist, vibration welding is performed with low surface pressure at the contact portion. At this time, welding between the case weld portion 35 and the cover weld portion 25 progresses slowly, and the weld layer 40 becomes thicker. This prevents a decrease in welding strength.

[0046] Figure 7 is a graph showing the relationship between the inclination angle θ of the inclined surface and the burst strength of pump 1. The horizontal axis of Figure 7 is the inclination angle θ, the same as the horizontal axis of Figure 6. The vertical axis of Figure 7 is the burst strength of pump 1. The burst strength of pump 1 is the pressure at which welded layer 40 ruptures when suction port 23 and discharge port 24 are sealed and the internal pressure of pump 1 is increased.

[0047] The examples where θ was Adeg and Bdeg exceeded the lower limit of the burst strength required for a product, as did the comparative example where θ was 0 deg. In the examples, welding progressed slowly in the base end region 38b in the -Z direction of the molten region 38, where the inclined surface 36 was not present. This is thought to have resulted in a thicker welded layer 40 and ensured sufficient weld strength. The burst strength of the examples was slightly reduced compared to the comparative example. In the examples, it is thought that the influence of the tip end region 38a in the +Z direction, where the inclined surface 36 was present, made the welded layer 40 slightly thinner compared to the comparative example. When θ was Bdeg, the burst strength was slightly reduced compared to when θ was Adeg. In the former, it is thought that the tip end region 38a in the +Z direction, where the inclined surface 36 was present, was larger, making the welded layer 40 slightly thinner compared to the latter.

[0048] As described above in detail, the pump 1 of this embodiment includes a case 30 and a cover 20. The case 30 has a case first opening 31 at its end in the Z direction along the central axis C. The case 30 houses the components of the pump 1 on its inner side in the R direction, which is perpendicular to the central axis C. The case 30 has a case weld 35 along the periphery of the case first opening 31. The cover 20 is arranged next to the case 30 in the Z direction. The cover 20 has a cover opening 21 facing the case first opening 31. The cover 20 has a cover weld 25 along the periphery of the cover opening 21. One of the case weld 35 and the cover weld 25 is referred to as a first weld, and the other is referred to as a second weld. In this case, an inclined surface 36 is formed at the tip of the first weld in the Z direction, sloping away from the second weld from the inside to the outside in the R direction. At the tip of the second welded portion in the Z direction, a tip surface 27 that intersects with the Z direction is formed. The first welded portion and the second welded portion are joined by vibration welding. In the embodiment, the case weld 35 is the first weld and the cover weld 25 is the second weld. Alternatively, the cover weld 25 may be the first weld and the case weld 35 may be the second weld.

[0049] Since an inclined surface 36 is formed at the tip of the first welded portion, the contact area between the first welded portion and the second welded portion is smaller, resulting in greater surface pressure. The temperature of the contact portion rises quickly due to frictional heat between the first welded portion and the second welded portion. The rubbing at the contact portion ends in a short time, and the contact portion melts quickly. This suppresses the generation of powder burrs due to rubbing at the contact portion. The inclined surface 36 of the first welded portion abuts against the second welded portion sequentially from the inside in the R direction. The inside in the R direction of the portion where powder burrs are generated has already melted. The generated powder burrs are less likely to scatter in the R direction. This makes it less likely that powder burrs will remain inside the pump 1.

[0050] The volume of outer weld burrs 42 extending outward in the R direction from the weld layer 40 between the first welded portion and the second welded portion is smaller than the volume of inner weld burrs 41 extending inward in the R direction from the weld layer 40. Since an inclined surface 36 is formed at the tip of the first welded portion, the volume of the melted region 38 of the first welded portion decreases from the inside to the outside in the R direction. Therefore, the volume of the outer weld burr 42 generated by melting of the melted region 38 is smaller than the volume of the inner weld burr 41.

[0051] The pump 1 has an inner standing wall 41w and an outer standing wall 42w. The inner standing wall 41w is disposed inward in the R direction and spaced apart from the first welded portion and the second welded portion. The outer standing wall 42w is disposed outward in the R direction and spaced apart from the first welded portion and the second welded portion. The inner standing wall 41w prevents the inner welding burr 41 from flowing into the inside of the pump 1. The outer standing wall 42w prevents the outer welding burr 42 from flowing out of the pump 1.

[0052] The manufacturing method of the pump 1 of the embodiment is a manufacturing method of a pump 1 having a case 30 and a cover 20. The case 30 has a case first opening 31 at an end in the Z direction along the central axis C. The case 30 houses the components of the pump 1 on the inside in the R direction, which is perpendicular to the central axis C. The case 30 has a case weld 35 along the periphery of the case first opening 31. The cover 20 is arranged next to the case 30 in the Z direction. The cover 20 has a cover opening 21 facing the case first opening 31. The cover 20 has a cover weld 25 along the periphery of the cover opening 21. One of the case weld 35 and the cover weld 25 is referred to as the first weld, and the other is referred to as the second weld. An inclined surface 36 is formed at the tip of the first welded portion in the Z direction, sloping away from the second welded portion from the inside to the outside in the R direction, and a tip surface 27 that intersects with the Z direction is formed at the tip of the second welded portion in the Z direction, and the first welded portion and the second welded portion are joined by vibration welding.

[0053] Since an inclined surface 36 is formed at the tip of the first welded portion, the contact area between the first welded portion and the second welded portion is smaller, resulting in greater surface pressure. The temperature of the contact portion rises quickly due to frictional heat between the first welded portion and the second welded portion. The rubbing at the contact portion ends in a short time, and the contact portion melts quickly. This suppresses the generation of powder burrs due to rubbing at the contact portion. The inclined surface 36 of the first welded portion abuts against the second welded portion sequentially from the inside in the R direction. The inside in the R direction of the portion where powder burrs are generated has already melted. The generated powder burrs are less likely to scatter in the R direction. This makes it less likely that powder burrs will remain inside the pump 1.

[0054] A plane 37 intersecting the Z direction is formed inside in the R direction of the inclined surface 36 at the tip of the first weld in the Z direction, and the first weld and second weld are joined by vibration welding. By having flat surface 37 of the first welded portion abut against the second welded portion, damage to the tip of the first welded portion is suppressed compared to when flat surface 37 is not present at the tip of the first welded portion.

[0055] The area of ​​the first weld that is melted by vibration welding is referred to as melted area 38. Height 36z of inclined surface 36 in the Z direction is smaller than height 38z of melted area 38 in the Z direction. The melting region 38 has a distal region 38a where the inclined surface 36 is present and a proximal region 38b where the inclined surface 36 is not present. In the proximal region 38b where the inclined surface 36 is not present, vibration welding is performed with low surface pressure at the contact points. At this time, welding between the first and second welded portions progresses slowly, and the weld layer 40 becomes thicker. This prevents a decrease in welding strength.

[0056] The width of the second welded portion in the R direction is greater than the width of the first welded portion in the R direction. As a result, vibration welding is carried out while maintaining contact between the tip of the first weld portion, on which the inclined surface 36 is formed, and the second weld portion.

[0057] In the embodiment, inclined surface 36 and flat surface 37 are formed at the tip of case weld 35. Alternatively, only inclined surface 36 may be formed at the tip of case weld 35. In this case, inclined surface 36 is inclined so as to move away from cover weld 25 from the end of case weld 35 in the -R direction to the end of case weld 35 in the +R direction.

[0058] In the embodiment, the inclined surface 36 is a flat surface. However, the inclined surface 36 may be a curved surface. The inclined surface 36 may be a curved surface that bulges outward from the case welded portion 35, or a curved surface that is recessed inward from the case welded portion 35. In this embodiment, the case weld portion 35 and the cover weld portion 25 are joined by vibration welding. Alternatively, the case weld portion 35 and the cover weld portion 25 may be joined by welding such as spin welding. Spin welding generates powder burrs, just like vibration welding.

[0059] The automotive cooling component of the embodiment is a pump such as an electric water pump, but the automotive cooling component of the present disclosure can also be applied to various cooling components other than pumps, such as valves and cooling modules in which a pump and a valve are integrated.

[0060] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modified examples may be combined as appropriate. [Explanation of symbols]

[0061] C…Central axis 1...Pump (automotive cooling part) 20...Cover 21...Cover opening 25...Cover welded part 27...Tip surface (plane) 30…cases 31...Case first opening (case opening) 35...Case welded part 36…Slope surface 37…Plane 38...Melting area 40...welding layer 41...Inner welding burr 41w…Inner standing wall 42...Outer welding burr 42w…Outside standing wall

Claims

1. a case having a case opening at an end in a first direction along a central axis, accommodating pump components on an inner side in a second direction perpendicular to the central axis, and having a case welding portion along a periphery of the case opening; a cover arranged next to the case in the first direction, having a cover opening facing the case opening, and having a cover welding portion along a periphery of the cover opening; When one of the case weld portion and the cover weld portion is a first weld portion and the other is a second weld portion, a sloped surface is formed at a tip of the first welded portion in the first direction, the sloped surface being inclined from the inside to the outside in the second direction so as to move away from the second welded portion; a plane intersecting the first direction is formed at a tip of the second welded portion in the first direction, The first welded portion and the second welded portion are joined by welding. Automotive cooling parts.

2. a volume of an outer weld burr extending outward in the second direction from a welding layer between the first weld portion and the second weld portion is smaller than a volume of an inner weld burr extending inward in the second direction from the welding layer; The automotive cooling component according to claim 1.

3. an inner standing wall disposed inward in the second direction and spaced apart from the first welded portion and the second welded portion; an outer standing wall disposed outward in the second direction and spaced apart from the first welded portion and the second welded portion; 3. The automotive cooling component according to claim 1 or 2.

4. a case having a case opening at an end in a first direction along a central axis, accommodating pump components on an inner side in a second direction perpendicular to the central axis, and having a case welding portion along a periphery of the case opening; a cover arranged next to the case in the first direction, having a cover opening facing the case opening, and having a cover welding portion along a periphery of the cover opening, When one of the case welded portion and the cover welded portion is a first welded portion and the other is a second welded portion, an inclined surface is formed at the tip of the first welded portion in the first direction, inclined so as to move away from the second welded portion from the inside to the outside in the second direction, and a flat surface intersecting the first direction is formed at the tip of the second welded portion in the first direction, so that the first welded portion and the second welded portion are joined by welding. Manufacturing method for automotive cooling parts.

5. a plane intersecting the first direction is formed on the inner side, in the second direction, of the inclined surface at the tip of the first welded portion in the first direction, and the first welded portion and the second welded portion are joined by welding; The method for manufacturing an automotive cooling part according to claim 4.

6. When a region of the first welded portion that melts due to the welding is defined as a melted region, a height of the inclined surface in the first direction being smaller than a height of the melted region in the first direction; The method for manufacturing an automotive cooling part according to claim 4 or 5.

7. a width of the second welded portion in the second direction that is greater than a width of the first welded portion in the second direction; The method for manufacturing an automotive cooling part according to claim 4 or 5.

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