JP5796346B2 - Manufacturing method of stator housing - Google Patents

Description

  The present invention relates to a method of manufacturing a stator housing (also referred to as a frame) that functions as a housing for accommodating a stator of an electric motor, and more particularly, a stator housing having a coolant passage for a cooling medium, such as a water-cooled stator housing. It is related with the manufacturing method.

  Patent Document 1 proposes a structure of a water-cooled stator housing having cooling water passages that are continuous in the circumferential direction while repeating meandering several times within the axial length.

Japanese Utility Model Publication No. 5-88185

  In the technique described in Patent Document 1, since the stator housing is manufactured by casting or aluminum die casting, a so-called collapsible core ( Sand cores, salt cores, or low melting point soluble metal cores) are required, and there is still room for improvement in terms of productivity and economy.

  The present invention has been made paying attention to such problems, and easily manufactures a stator housing having a plurality of meandering refrigerant passages without using a collapsible core typified by a sand core. The present invention provides a method for manufacturing a stator housing.

The present invention provides a casting made of an inner peripheral mold and an outer peripheral mold for manufacturing a cylindrical stator housing having a refrigerant passage continuous in the circumferential direction while repeating meandering within an axial length. Prepare a mold. The inner peripheral mold has a jacket core that controls the formation of the refrigerant passage with a substantially comb shape, and two mold elements in the middle of the flow path length in the axial direction of the stator housing in the refrigerant passage. It is assumed that it is divided into Then, both mold elements including the jacket core are abutted in the axial direction of the stator housing to form an inner peripheral mold, and an outer peripheral mold is combined with the inner peripheral mold to separate the inner peripheral mold from the outer peripheral mold. are have rows casting by pouring molten metal into the product shape portion space was, with the shape of the jacket core and to form a refrigerant passage of the reverse shape that is transferred.

  According to the present invention, it is possible to manufacture a stator housing having refrigerant passages meandering several times by simply preparing a mold composed of a combination of an inner peripheral type and an outer peripheral type, which is essential in the past. By eliminating the need for the collapsible core, productivity and economy are excellent.

  More specifically, the material for the collapsible core and the equipment for manufacturing the core are not necessary, and there are no restrictions on the casting method. For example, the HPDC method (high pressure die casting method) In addition, select any casting method according to the number of production from the gravity casting method, low pressure casting method, LPDC (low pressure die casting method), SDC (squeeze die casting method or molten metal forging method), etc. Since it can be manufactured, both productivity and economy are good.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows schematic structure of the water-cooled motor as a 1st form for implementing this invention. FIGS. 2A and 2B are views showing a relationship between a stator housing and a cooling water passage formed therein, and FIG. 2A is a perspective view of the stator housing alone, and FIG. 2B is a cooling water passage formed inside the stator housing. FIG. 3 is a perspective view showing only a cooling water passage extracted from a stator housing for easy understanding. FIG. The schematic explanatory drawing at the time of mold opening of the metal mold | die structure for casting the stator housing shown in FIG. Explanatory drawing at the time of the mold clamping of the outer periphery type | mold in FIG. (A), (B) is explanatory drawing at the time of clamping of the outer periphery type | mold and inner periphery type | mold in FIG. The perspective view which shows another example of a cooling water channel | path as a 2nd form for implementing this invention. Explanatory drawing of the draft set to the jacket core shown in FIG.

  1 and 2 are views showing a more specific first embodiment for carrying out the present invention. FIG. 1 shows a schematic structure of a water-cooled motor used as a drive source of an electric vehicle, for example, and FIG. 2 shows details of the stator housing 1 in FIG.

  As shown in FIG. 1, a cylindrical stator housing (hereinafter simply referred to as “housing”) 1 has a predetermined wall thickness, for example, by an aluminum alloy or the like by a die casting method such as the HPDC method (high pressure die casting method). It was manufactured as an integral part. As is well known, the housing 1 houses a rotor together with a stator (not shown), and the openings on both sides thereof are closed or sealed by the front and rear housing covers 2 and 3.

  2A shows the external shape of the housing 1 alone shown in FIG. 1, and FIG. 2B shows the tertiary of the cooling water passage 6 formed as a refrigerant passage inside the housing 1. In order to make the original shape easy to understand, only the cooling water passage 6 is extracted from the housing 1 of FIG.

  Between the inner peripheral wall portion 4 and the outer peripheral wall portion 5 of the housing 1 shown in FIG. 2A, as shown in FIG. 2B, meandering several times within the axial length of the housing 1 A single cooling water passage 6 is formed as a refrigerant passage continuous in the circumferential direction while repeating the above. A portion of the cooling water passage 6 corresponding to the U-turn folded portion 7 faces both end faces of the housing 1 as openings 7 a, and these openings 7 a are attached to both end faces of the housing 1. The housing covers 2 and 3 are closed.

  The cooling water passage 6 is filled with a partition wall 8 or the like other than the region of the cooling water passage 6 itself shown in FIG. 2B with a partition wall 8 interposed between the inner peripheral wall portion 4 and the outer peripheral wall portion 5 of the housing 1. As a result, a space as the cooling water passage 6 is secured. The cooling water passage 6 is a specific location in the circumferential direction of the housing 1, and the continuity is cut off at an intermediate position 9 that bisects the flow path length in the axial direction of the housing 1.

  In other words, a part of the partition wall 8 interposed between the inner peripheral wall part 4 and the outer peripheral wall part 5 exists at a position corresponding to the intermediate position 9, and the partition wall corresponding to the intermediate position 9 Is the intermediate partition wall 8a, the continuity of the cooling water passage 6 is interrupted by the presence of the intermediate partition wall 8a, and one of the end portions of the cooling water passage 6 at the positions closest to both sides of the intermediate partition wall 8a is the cooling water. The start end 10 of the passage 6 and the other end 11 of the cooling water passage 6 are provided. And since the inflow port 12 and the outflow port 13 for cooling water are formed adjacent to the outer peripheral wall portion 5 of the housing 1 shown in FIG. The start end portion 10 communicates with the inflow port 12 and the end portion 11 of the cooling water passage 6 communicates with the outflow port 13.

  As a result, between the inner peripheral wall portion 4 and the outer peripheral wall portion 5 of the housing 1, continuous in the circumferential direction while repeating meandering within the axial length of the housing 1 from the inflow port 12 toward the outflow port 13. A one-way single cooling water passage 6 is formed.

  FIG. 3 shows an example of a mold structure for manufacturing the housing 1 by a die casting method. The mold 14 is roughly divided into an inner peripheral mold 15 and an outer peripheral mold 16, and the inner peripheral mold 15 includes a fixed mold 25A as a pair of half-shaped mold elements that can approach and separate from each other in the left-right direction in FIG. It is divided into the movable mold 25 </ b> B and mainly controls the molding of the inner peripheral wall portion 4 including the cooling water passage 6 of the housing 1. A split surface between the fixed mold 25A and the movable mold 25B (which is a butting surface of both when mold clamping described later) is set at a position that bisects the housing 1 in the axial direction. On the other hand, the outer peripheral mold 16 is divided into an upper mold 26A and a lower mold 26B as a pair of halved mold elements that can approach and separate from each other in the vertical direction of FIG. I'm in charge of molding. A split surface of the upper mold 26A and the lower mold 26B (which is a butting surface of both when mold clamping described later) is set at a position that bisects the housing 1 in the radial direction.

  The fixed mold 25A and the movable mold 25B are positioned on the outer peripheral side of the core body 17 in addition to the solid cylindrical core body 17 that controls the molding of the inner peripheral wall 4 as shown in FIG. A jacket core 18 for controlling the formation of the water passage 6 is provided. Each of the jacket cores 18 can be understood as a shape in which the shape of the cooling water passage 6 shown in FIG. 2 is divided into two equal parts in the axial direction of the housing 1, and the developed shape forms a substantially comb shape. Yes. As a result, when the core bodies 17 and 17 of the fixed mold 25A and the movable mold 25B are abutted with each other as shown in FIG. 5, the jacket cores 18 and 18 are also abutted with each other, substantially as shown in FIG. The cooling water passage 6 functions as a metal core having the same shape. The core here refers to a metal core that constitutes a part of the mold 14 and can be used repeatedly unlike a conventional collapsible core.

  At the time of mold clamping, as shown in FIG. 3, with the fixed mold 25A and the movable mold 25B facing away from each other, the upper and lower molds 26A and 26B are clamped from above and below with the movable mold 25B as the center. The state shown in FIG. From the state of FIG. 4, the movable mold 25B and the upper and lower molds 26A and 26B are moved as a set toward the fixed mold 25A, and the fixed mold 26A and the movable mold 26B are clamped.

  FIG. 5 shows a state in which the upper mold 26A and the lower mold 26B, which are the mold elements of the outer peripheral mold 16, are clamped in addition to the fixed mold 25A and the movable mold 25B that are the mold elements of the inner peripheral mold 15, respectively. . FIGS. 5A and 5B are the same, and only the viewing direction is different. However, in FIGS. 2A and 2B, the upper and lower molds 26A and 26B are not shown to show the shape of the inner jacket core 18 in a perspective view.

  As is clear from FIGS. 4 and 5, the core bodies 17 and 17 of the fixed mold 25A and the movable mold 25B, which are the mold elements of the inner mold 15, are brought into contact with each other inside the outer mold 16 composed of the upper and lower molds 26A and 26B. At the same time, the jacket cores 18 and 18 are abutted with each other. As a result, a product shape portion space corresponding to the shape of the housing 1 in FIG. 2 is isolated and formed between the inner peripheral die 15 and the outer peripheral die 16 in the clamped state. At the same time, the shapes of the two jacket cores 18 and 18 that face each other coincide with the shape of the cooling water passage 6 shown in FIG.

  Therefore, in the mold-clamping state as shown in FIG. 5, die casting is performed by pouring molten metal into the product shape part space formed separately between the inner peripheral die 15 and the outer peripheral die 16 by a known method. Thus, the housing shown in FIG. 2A having the inverted shape in which the shapes of the inner peripheral die 15 and the outer peripheral die 16 are transferred in a form including the shape of the cooling water passage 6 shown in FIG. 1 will be cast.

  In this case, a position corresponding to the intermediate position 9 in FIG. 2B, that is, a part of the butted portion between the jacket cores 18 and 18 shown in FIG. Is formed, and a predetermined intermediate partition wall 8a is formed as an inverted shape of the butted portion 19. Therefore, in this portion, the continuity as the cooling water passage 6 is cut off on both sides of the intermediate partition wall 8a, and as described with reference to FIG. 2, the cooling water passage 6 in the position closest to both sides of the intermediate partition wall 8a. One of the terminal portions is formed as the start end portion 10 of the cooling water passage 6 and the other is formed as the end portion 11 of the cooling water passage 6.

  An inflow port 12 that opens to the outer periphery of the housing 1 and communicates with the start end portion 10 of the cooling water passage 6 and an outflow port 13 that communicates with the end portion 11 of the cooling water passage 6. Can be formed at the same time as the die-casting by a so-called casting method, but may be formed by machining in a later process.

  FIG. 6 shows another example of the cooling water passage 6 formed in the housing 1 as a second embodiment for carrying out the present invention.

  In this example, partition wall corresponding portions 9 are set at two locations facing the circumferential direction of the housing 1 in the cooling water passage 6 that continues in the circumferential direction while repeating meandering within the axial length of the housing 1, An intermediate partition wall 8a is formed in each of the inverted shapes of the partition equivalent portions 9.

  By disconnecting the continuity as the cooling water passage 6 at the intermediate partition walls 8a set in two places in this way, the cooling water passages 6A and 6B of the first and second systems which are independent from each other in the circumferential direction of the housing 1 are obtained. Can be formed. In this case, for example, one of the end portions of the cooling water passage 6 at the position closest to both sides of the one partition equivalent portion 9 is the start end portion 10 of the first cooling water passage 6A, and the other is the end of the second cooling water passage 6B. Part 11. Similarly, one of the end portions of the cooling water passage 6 at the positions closest to both sides of the other partition wall equivalent portion 9 is the start end portion 10 of the second cooling water passage 6B, and the other is the end portion 11 of the first cooling water passage 6A. It becomes.

  As described above, in the first and second embodiments, the cooling water passage 6 is formed by using the jacket core 18 that is abutted in the axial center direction of the housing 1. There is no need to use a collapsible core. Therefore, not only materials for collapsible cores and equipment for core production are not required, but there are no restrictions on casting methods. For example, in addition to HPDC method (high pressure die casting method), gravity casting The housing 1 is cast by selecting an arbitrary casting method according to the number of production, etc., from among other methods, low pressure casting method, LPDC (low pressure die casting method), SDC (squeeze die casting method or molten metal forging method), etc. Therefore, both productivity and economy are excellent.

  In addition, when the mold is opened, the fixed mold 25A having the jacket core 18 and the movable mold 25B are separated from each other in the direction to be separated from each other, and are extracted from the housing 1 as a product. It can disperse | distribute to the type | mold 25B, and generation | occurrence | production of a chip | tip defect | deletion, a crack, etc. can be suppressed.

  Further, in the cooling water passage 6, the partition wall equivalent portion 9 is located in the middle of the flow path length in the axial direction of the housing 1, more specifically, at a position that bisects the flow path length in the axial direction of the housing 1. Since the intermediate partition wall 8a is formed as the inverted shape, the inflow port 12 and the outflow port 13 can be formed on both sides of the intermediate partition wall 8a of the housing 1 by casting or machining. . Since the inflow port 12 and the outflow port 13 can be set directly on the outer peripheral surface of the housing 1 in this way, it is possible to reduce the size of the extra protrusions as much as possible when assembling as an electric motor (motor) and to make the apparatus compact. it can.

  Furthermore, since it becomes easy to divide the cooling water passage 6 into two systems by increasing the partition equivalent portion 9 as in the second embodiment, the circle of the housing 1 can be obtained by forming the cooling water passage 6 into a plurality of systems. It is also possible to reduce the strength of the cooling effect in the circumferential direction and make it uniform.

  Here, as shown in FIGS. 3 to 5, when the fixed mold 25 </ b> A and the movable mold 25 </ b> B, which are the mold elements of the inner peripheral mold 15, are moved toward and away from each other, that is, when the mold clamping and mold opening operations are performed, the core body 17. In addition, it is usual to set a draft angle for the jacket core 18. FIG. 7B schematically shows a part of the jacket core 18 used in the above-described form. Both the jacket cores 18, 18 are set to the axial length of the housing 1. As described above, the channel length in the axial direction is abutted at a position that bisects the channel length. When the draft angle set for the jacket core 18 is taken into consideration, the relationship between the dimension a on the base side when the jacket cores 18 and 18 are butted together and the dimension b of the butted portion is a> b <a.

  On the other hand, as shown in FIG. 7A, the jacket core 18 is set only to one of the fixed mold 25A and the movable mold 25B, for example, the movable mold 25B side, and the jacket core 18 is abutted against the fixed mold 25A. Assuming that the casting is performed, and considering the draft angle set for the jacket core 18, the relationship between the dimension a on the base side of the jacket core 18 and the dimension c of the butted portion is a> c.

  Thereby, in the thing of the 1st, 2nd form shown to (B) of FIG. 7, the said dimensional relationship becomes a> b <a and b> c, and it is in the butt | matching part of jacket cores 18 and 18 mutually. The cross-sectional change, that is, the change in the cross-sectional area of the cooling water passage 6 that is formed as the inverted shape of the jacket cores 18 and 18 can be made smaller than that shown in FIG. it can. As a result, it is not necessary to increase the flow resistance of the cooling water in the cooling water passage 6.

  Needless to say, the present invention can be similarly applied to a casting method using a mold, as described above, other than the die-casting method.

1 ... Stator housing 6 ... Cooling water passage (refrigerant passage)
6A ... 1st cooling water passage (1st refrigerant passage)
6B ... second cooling water passage (second refrigerant passage)
8a ... Intermediate partition 10 ... Start end 11 ... Terminal 14 ... Mold 15 ... Inner peripheral mold 16 ... Outer peripheral mold 17 ... Core body 18 ... Jack core 25A ... Fixed mold (mold element)
25B ... Movable type (mold element)

Claims (4)

A method of manufacturing a cylindrical stator housing having a refrigerant passage continuous in the circumferential direction while repeating meandering within an axial length by a casting method,
Molds for casting consist of inner and outer peripheral molds,
The inner peripheral type is divided into two type element in the middle of the flow path length in the axial direction of the stator housing of the refrigerant passage Rutotomoni,
Each mold element is provided with a jacket core that controls the formation of the refrigerant passage by forming a substantially comb shape.
Both mold elements including the jacket core are abutted in the axial direction of the stator housing to form an inner peripheral mold and an outer peripheral mold in combination with this.
Characterized by forming the refrigerant passage of the reverse shape to have the line casting by pouring molten metal into quarantine formed product shape portion space, the shape of the jacket core has been transferred between the inner mold and the outer peripheral-type A method for manufacturing a stator housing. The inner peripheral type stator housing according to claim 1, characterized in that it is divided into two type element in the flow path length bisecting position in the axial direction of the stator housing of the refrigerant passage Production method. In one place in the circumferential direction of the stator housing, by separating the continuity as the refrigerant passage by forming a partition wall in the refrigerant passage at a position that bisects the flow path length in the axial direction of the stator housing,
3. The method of manufacturing a stator housing according to claim 2 , wherein one of the end portions of the refrigerant passage at positions closest to both sides of the partition wall is formed as a starting end portion of the refrigerant passage and the other is formed as an end portion of the refrigerant passage . In Nica plants circumferential direction of the stator housing, by breaking the continuity of the refrigerant passage forms a partition wall in the flow path length bisecting position in the axial direction of the stator housing of the refrigerant passage, Forming the first and second two refrigerant passages independent of each other in the circumferential direction of the stator housing;
One of the end portions of the refrigerant passage at the positions closest to both sides of the one partition wall is formed as the first end portion of the first refrigerant passage, and the other is formed as the end portion of the second refrigerant passage ,
4. One of the end portions of the refrigerant passage at the positions closest to both sides of the other partition wall is formed as a start end portion of the second refrigerant passage, and the other is formed as an end portion of the first refrigerant passage. Method for manufacturing a stator housing.

Images