JP5799746B2 - Manufacturing method of electric motor - Google Patents

Description

The present invention relates to the production how the electric motor to generate a rotating force by a magnetic force.

  In recent years, electric motors in which permanent magnets and coils are arranged on a rotor (rotor) are used in electric vehicles and the like. This electric motor has a high energy density in response to demands for smaller size, higher output, and higher speed. For this reason, the rotor is likely to become high temperature, causing a loss of the entire motor and demagnetization of a permanent magnet used in the motor.

  Therefore, for example, it is necessary to monitor the temperature of the permanent magnet in the rotor and control the motor in accordance with the temperature of the permanent magnet. However, since the rotor on which the permanent magnet is arranged is a rotating body, it is difficult to transmit the temperature measurement result to the stator (stator) side by wire.

  Therefore, the temperature of the permanent magnet of the rotor is measured by a temperature sensor disposed on the rotor and transmitted to the stator wirelessly (for example, Patent Document 1), or laser light is applied to a transparent member whose refractive index changes depending on the temperature disposed on the rotor. And a method of estimating the rotor temperature from the refraction of the transmitted laser light has been proposed (for example, Patent Document 2). Furthermore, a method of attaching a thermocouple to the permanent magnet of the rotor and outputting to the stator side via a slip ring is also conceivable.

JP 2006-94576 A JP 2010-35265 A

  However, in the configuration using radio or laser light as described above, the structure of the motor becomes complicated and the cost increases. In addition, when wireless is used, the accuracy of measurement values may be reduced due to the influence of noise mixed in the wireless signal. In addition, in the configuration using the slip ring, the contact portion may be worn out by long-term use, or the contact portion may be damaged due to the influence of vibration, which may reduce the reliability of the measurement value.

The present invention aims at providing such a problem in view of the long-term stable production how a motor that can be inexpensively realize a configuration for monitoring the temperature of the rotor.

  In order to solve the above-mentioned problems, an annular stator of the present invention, and a rotor that is inserted into the stator ring and is rotatably supported in the circumferential direction in a state of being separated from the inner peripheral surface of the stator. A manufacturing method for manufacturing an electric motor includes a cylindrical molding jig having an outer diameter smaller than an inner diameter of a stator, and a notch portion that is an axial notch formed on a part of the outer periphery thereof, and a notch A molding jig insertion process for inserting a temperature measuring section having a smaller cross-sectional area than the section into the stator ring and introducing the solidified material before solidification into the gap between the molding jig and the stator. The method includes a step, an extraction step of extracting the molding jig from the stator after the solidified material is solidified, and a rotor insertion step of inserting the rotor into the stator ring.

  Prior to the molding jig insertion step, there may be further provided an adhesion step for adhering the temperature measuring portion to the surface of the molding jig on the side of the notch portion.

  A groove is formed in the cutout portion in the axial direction, and the temperature measurement unit may be disposed in the groove in the molding jig insertion step or the bonding step.

In order to solve the above-mentioned problems, the present invention includes an annular stator, and a rotor that is inserted into the stator ring and rotatably supported in the circumferential direction in a state of being separated from the inner peripheral surface of the stator. A manufacturing method for manufacturing an electric motor is such that a winding is inserted into a slot portion, which is a groove extending in the axial direction of the stator, provided on the inner peripheral surface of the stator, and wound around an intervening portion of two adjacent slot portions. A coil winding process for winding a wire to generate a coil , an adhesion process for bonding a temperature measurement unit to a side surface of a forming jig , and a temperature measurement unit for measuring temperature in the slot portion, having an outer diameter smaller than the inner diameter of the stator A molding jig insertion process for inserting a cylindrical molding jig into the stator ring, an introduction process for introducing a solidified material before solidification into the slot, and a molding jig after the solidified material is solidified Is extracted from the stator. And extraction step, the rotor, and having a rotor insertion step for inserting into the stator ring.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to implement | achieve the structure which monitors the temperature of a rotor stably for a long time at low cost.

It is sectional drawing of an electric motor. It is sectional drawing of an electric motor. It is a flowchart which shows the manufacturing method of an electric motor. It is explanatory drawing for demonstrating the shaping | molding jig | tool with which the temperature measurement part was adhere | attached. It is explanatory drawing for demonstrating the shaping | molding jig | tool in the modification 1. FIG. 10 is a flowchart showing a method for manufacturing an electric motor in Modification 1. It is explanatory drawing for demonstrating the shaping | molding jig | tool in the modification 2. 10 is a flowchart showing a method for manufacturing an electric motor in Modification 2.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Electric motor 100)
1 and 2 are cross-sectional views of the electric motor 100. FIG. FIG. 1 shows a cross section including the rotating shaft of the electric motor 100, and FIG. 2 shows a cross section taken along line II-II in FIG. As shown in FIG. 1, the electric motor 100 includes a stator (stator) 120, a rotor (rotor) 122, a temperature measurement unit 124, and a fixing unit 126.

  As shown in FIG. 2, the stator 120 is formed in an annular shape so that a center hole 120a is formed. In the main body (stator core 120 b) of the stator 120, a plurality of (for example, eight) slot portions 120 c are provided at equal intervals in the circumferential direction of the stator 120. The slot portion 120c is configured by a groove in the stator 120 that extends in the axial direction of the rotation shaft.

  The center hole 120a of the ring of the stator 120 and the slot portion 120c are connected by a communication portion 120d, and a winding is wound around the interposition portion 120e between two adjacent slot portions 120c via the communication portion 120d. Thus, the coil 120f is formed.

  One coil 120f is arranged for each combination of two adjacent slot portions 120c. The partition plate 120g functions as a partition disposed in the communication portion 120d after the winding of the winding is completed.

  Mold resin is introduced into the gap between the slot 120c and the coil 120f, and the coil 120f is fixed with the mold resin (molding).

  As shown in FIG. 1, a through hole 100 c is provided in the end surface 100 b of the casing 100 a of the electric motor 100. The electric wire of the coil 120f is led out of the housing 100a through the through hole 100c. Further, bearings 100e are provided on the end faces 100b and 100d of the casing 100a, respectively.

  The rotor 122 is inserted through the ring of the stator 120 (center hole 120a). Then, the rotor 122 is arranged in the circumferential direction of the rotor 122 via the shaft 122b to the bearing 100e with the outer peripheral surface 122a spaced apart from the inner peripheral surface 120h in the ring of the stator 120 with a gap (air gap). It is pivotally supported. This air gap is, for example, about 0.5 mm to 1 mm.

  The main body (rotor core 122c) of the rotor 122 is provided with a through hole 122d through the shaft 122b at the center. Further, a portion (large diameter portion 122e) having a larger diameter than the other portions of the shaft 122b is fixedly installed in a state where the shaft 122b is inserted into the through hole 122d of the rotor 122.

  A plurality of permanent magnets 122f are fixed to the rotor core 122c at equal intervals in the circumferential direction of the rotor 122 on the outer peripheral side of the through hole 122d. The permanent magnet 122f is arranged so that either the N pole or the S pole faces the inner peripheral surface 120h of the stator 120.

  The temperature measurement unit 124 is a measuring element for measuring the temperature of the rotor 122, and is configured by a thermocouple in the present embodiment.

  As shown in FIG. 1, the temperature measurement unit 124 is guided from the through hole 100 c to the inside of the housing 100 a, and as shown in FIGS. 1 and 2, a portion of the stator 120 that faces the outer peripheral surface 122 a of the rotor 122. Arranged.

  As described above, by using an inexpensive thermocouple as the temperature measuring unit 124, the manufacturing cost of the electric motor 100 can be suppressed. Further, since the thermocouple is relatively small (for example, the diameter of the strand is about 0.1 mm), the thermocouple can be easily arranged even if the gap between the rotor 122 and the stator 120 of the electric motor 100 is narrow.

  The fixing portion 126 is made of a mold resin, and fixes the temperature measuring portion 124 to a portion of the stator 120 that faces the outer peripheral surface 122a of the rotor 122.

  A control unit (not shown) controls the number of revolutions of the electric motor 100 based on the temperature measured by the temperature measurement unit 124.

  For example, using a tester that can directly measure the temperature of the rotor 122 (for example, the temperature of the permanent magnet 122f), which is the temperature to be monitored, the operating status (load, rotation speed, magnet loss, etc.) of the motor 100 and monitoring The association data indicating the relationship between the temperature of the target (here, the permanent magnet 122f) and the measurement value of the temperature measurement unit 124 may be recorded in advance as a table.

  In this case, the control unit estimates the temperature to be monitored from the operating state of the electric motor 100 and the measured value measured by the temperature measuring unit 124 based on the pre-recorded association data, and controls the electric motor 100.

  Hereinafter, a method for manufacturing the above-described electric motor 100 will be described with reference to the flowchart of FIG.

(Method for manufacturing electric motor 100)
FIG. 3 is a flowchart showing a method for manufacturing the electric motor 100. As shown in FIG. 3, first, a winding is inserted into a slot portion 120c provided on the inner peripheral surface 120h of the stator 120, and the winding is wound around an interposition portion 120e between two adjacent slot portions 120c. 120f is generated (coil winding step S200).

  Subsequently, the forming jig and the temperature measuring unit 124 are prepared, and the temperature measuring unit 124 is bonded to the surface on the notch portion side of the forming jig (bonding step S202). Such a forming jig and its notch will be described with reference to FIG.

  FIG. 4 is an explanatory diagram for explaining the molding jig 300 to which the temperature measurement unit 124 is bonded. 4A is a front view of the molding jig 300, and FIG. 4B is a sectional view taken along line IV (b) -IV (b) of FIG. 4A. These are the elements on larger scale of FIG.4 (b).

  The molding jig 300 is a cylindrical member having an outer diameter smaller than the inner diameter of the stator 120. However, in order to reduce the amount of mold resin that oozes into the gap between the inner peripheral surface of the stator 120 and the outer peripheral surface of the molding jig 300 when the mold resin is introduced in the introduction step S206, which is a subsequent step, molding is performed. It is desirable that the outer diameter of the jig 300 be close to the inner diameter of the stator 120 as long as it can be fitted. The molding jig 300 has a notch 302 that is a notch in the axial direction formed on a part of the outer periphery thereof. The height L of the notch 302 in the radial direction of the shaft 122b is, for example, about 0.2 mm.

  The temperature measuring unit 124 is bonded to the notch 302 with an adhesive. For example, the adhesive melts at a lower temperature (for example, 80 degrees) than the heat resistance temperature (for example, 180 degrees) of the mold resin used as the fixing portion 126 and the molding temperature (for example, 120 degrees) for solidification. Used. Here, it is assumed that the temperature measurement unit 124 has a smaller cross-sectional area than the notch 302.

  By performing the bonding step S202, it is possible to easily place the temperature measurement unit 124 at a desired position only by inserting the molding jig 300 in the molding jig insertion step S204 described later.

  Then, the molding jig 300 to which the temperature measuring unit 124 is bonded is inserted into the ring of the stator 120 (molding jig insertion step S204).

  Subsequently, the solidified material before solidification is introduced into the gap between the molding jig 300 and the stator 120 (introduction step S206). Here, the solidifying material is a mold resin before the fixing portion 126 described above is solidified.

  Then, after the mold resin is heated and the mold resin is solidified to function as the fixing portion 126, the molding jig 300 is extracted from the stator 120 (extraction step S208). In the present embodiment, since an adhesive that melts at a low temperature is used in the bonding step S <b> 202, the adhesive melts and the temperature measuring unit 124 is separated from the molding jig 300 during heating for solidifying the mold resin. In addition, only the molding jig 300 can be easily extracted.

  Finally, the rotor 122 is inserted into the ring of the stator 120 (rotor insertion step S210), and the rotor 122 and the stator 120 are covered with the casing 100a. At this time, the cover is covered with the members constituting the end faces 100b and 100d of the housing 100a so that the shaft 122b is pivotally supported by the bearing 100e (completion step S212).

  FIG. 4D shows a partially enlarged view of FIG. In the molding jig insertion step S204 described above, an adhesive that bonds the temperature measurement unit 124 and the molding jig 300 is interposed. Therefore, in the introduction step S206, since the mold resin does not enter between the temperature measurement unit 124 and the molding jig 300, the temperature measurement unit 124 is exposed from the mold resin as shown in FIG. Touching the air in the air gap. In the present embodiment, the temperature measuring unit 124 is partially embedded in the mold resin and partially exposed. However, the temperature measuring unit 124 may be completely buried in the mold resin.

  As described above, according to the method for manufacturing the electric motor 100 of the present embodiment, the temperature measuring unit 124 is arranged closest to the permanent magnet 122f among the non-rotating parts of the electric motor 100 in order to measure the temperature of the air gap. It can be arranged on the inner peripheral surface 120 h of the ring of the stator 120.

  For example, in the PM (Permanent Magnet) motor in which the permanent magnet 122f is arranged on the rotor 122 like the electric motor 100, the thermal resistance between the inner peripheral surface 120h side of the stator 120 and the permanent magnet 122f is small and heat transfer is easy. Therefore, a temperature difference hardly occurs between the temperature of the air gap and the permanent magnet 122f, and the control unit that controls the electric motor 100 can accurately estimate the temperature of the permanent magnet 122f from the measured value of the temperature measuring unit 124.

  In addition, since the mold is formed by the molding jig 300 and the stator 120, the temperature measuring unit 124 can be easily molded simply by introducing mold resin into the gap. At this time, since the molding of the temperature measuring unit 124 can be performed simultaneously with the molding of the coil 120f, the work load for arranging the temperature measuring unit 124 is reduced.

(Modification 1)
Next, the molding jig 400, the notch portion 402, the groove 404, the bonding step S420, the fixing portion 426, and the convex portion 426a in Modification 1 will be described. In Modification 1, the molding jig 400, the notch 402, the groove 404, the bonding step S420, the fixing portion 426, and the convex portion 426a are different from the above embodiment. The description of the same configuration as the above embodiment is omitted, and only the molding jig 400, the notch portion 402, the groove 404, the bonding step S420, the fixing portion 426, and the convex portion 426a having different configurations will be described.

  FIG. 5 is an explanatory diagram for explaining the forming jig 400 in the first modification. 5A shows a front view of the forming jig 400, and FIG. 5B is a cross-sectional view taken along line V (b) -V (b) of FIG. 5A. These are the elements on larger scale of FIG.5 (b).

  As shown in FIGS. 5A and 5B, the molding jig 400 is a cylindrical member having an outer diameter smaller than the inner diameter of the stator 120, similar to the molding jig 300. The molding jig 400 has a notch 402 that is a notch in the axial direction formed on a part of its outer periphery. As shown in FIG. 5C, a groove 404 is formed in the notch 402 in the axial direction.

  FIG. 6 is a flowchart showing a method for manufacturing the electric motor in the first modification. After the coil winding step S200, the forming jig 400 and the temperature measuring unit 124 are prepared, and the temperature measuring unit 124 is bonded to the groove 404 of the notch 402 of the forming jig 400 (bonding step S420). Here, when the bonding step S420 is not performed, the temperature measurement unit 124 is disposed in the groove 404 in the molding jig insertion step S204.

  FIG. 5D shows a partially enlarged view of the position corresponding to FIG.

  The fixing portion 426 is made of a mold resin like the fixing portion 126. As shown in FIG. 5D, the fixed portion 426 has a convex portion 426 a that protrudes toward the radial center of the inner peripheral surface 120 h of the stator 120 at a position corresponding to the groove 404.

  By arranging (for example, bonding) the temperature measurement unit 124 in the groove 404 of the notch 402, the temperature measurement unit 124 is configured so that the mold resin (fixing unit 426) is the ring of the stator 120 after heating the mold resin. A part or all of the protrusions 426a raised in the inner diameter direction are embedded.

  Thus, in the configuration in which only the convex portion 426a protrudes in the inner diameter direction, it is only necessary to maintain only the distance between the tip of the convex portion 426a and the rotor 122 with high accuracy compared to the configuration in which the entire mold resin is raised in the inner diameter direction. Molding along the design dimensions of the resin becomes easy. Further, the temperature measurement unit 124 can measure the temperature of the air gap more accurately by arranging the temperature measurement unit 124 on the convex portion 426a and reducing the volume of the mold resin near the temperature measurement unit 124.

(Modification 2)
Next, the molding jig 500, the bonding step S520, the molding jig insertion step S522, the introduction step S524, and the fixing portion 526 in Modification 2 will be described. In the modified example 2, the molding jig 500, the bonding step S520, the molding jig insertion step S522, the introduction step S524, and the fixing portion 526 are different from the above embodiment. The description of the same configuration as the above embodiment is omitted, and only the molding jig 500, the bonding step S520, the molding jig insertion step S522, the introduction step S524, and the fixing portion 526 having different configurations will be described.

  FIG. 7 is an explanatory diagram for explaining the forming jig 500 in the second modification. 7A shows a front view of the forming jig 500, and FIG. 7B is a cross-sectional view taken along the line VII (b) -VII (b) of FIG. 7A. These are the elements on larger scale of FIG.7 (b).

  The molding jig 500 is a cylindrical member having an outer diameter smaller than the inner diameter of the stator 120, similar to the molding jig 300. However, as shown in FIGS. 7A, 7 </ b> B, and 7 </ b> C, the molding jig 500 is not provided with the notch 302. The temperature measuring unit 124 is bonded to the side surface of the molding jig 500 with an adhesive.

  FIG. 8 is a flowchart showing a method for manufacturing the electric motor in Modification 2. After the coil winding step S200, the forming jig 500 and the temperature measuring unit 124 are prepared, and the temperature measuring unit 124 is bonded to the surface of the side surface of the forming jig 500 (bonding step S520). Here, when the bonding step S520 is not performed, the temperature measurement unit 124 is disposed in the slot portion 120c in the molding jig insertion step S522.

  Then, the molding jig 500 to which the temperature measurement unit 124 is bonded is inserted into the ring of the stator 120 so that the temperature measurement unit 124 is arranged in the slot 120c (molding jig insertion step S522).

  Then, a solidified material (mold resin) before solidification is introduced into the slot portion 120c (introduction step S524).

  FIG. 7D shows a partially enlarged view of the vicinity of the slot 120 c in the second modification.

  The fixing part 526 is the mold resin introduced into the gap between the slot part 120c and the coil 120f described above, and the temperature measurement part 124 is embedded in the fixing part 526 as shown in FIG. .

  Thus, in the modified example in which the temperature measuring unit 124 is inserted and fixed into the slot 120c, the molding jig 500 used for molding the conventional coil 120f can be used as it is. Therefore, the temperature measuring unit 124 can be arranged near the air gap without preparing a new dedicated molding jig, and the controller of the electric motor 100 can estimate the temperature of the permanent magnet 122f from the temperature of the air gap. It becomes.

  Further, as shown in the above-described embodiments and modifications, part or all of the temperature measurement unit 124 is embedded in the fixing unit, so that the temperature measurement unit 124 can be reliably fixed and durability can be improved. .

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  In the embodiment described above, the bonding step is performed before the molding jig insertion step, but the molding jig insertion step may be performed without performing the bonding step.

  In the above-described embodiment, the permanent magnet 122f is disposed on the rotor 122 and the temperature of the permanent magnet 122f is monitored. However, a coil is disposed on the rotor instead of the permanent magnet, and the temperature of the coil is monitored. Also good.

  In the above-described embodiment, the control unit estimates the temperature to be monitored based on the association data recorded in advance and controls the electric motor 100. However, the association data is not recorded in advance. In any case, the measurement value itself of the temperature measurement unit 124 or a value obtained by adding a predetermined constant to the measurement value of the temperature measurement unit 124 may be regarded as the temperature to be monitored.

  Each step in the method for manufacturing an electric motor of the present specification does not necessarily have to be processed in time series in the order described in the flowchart, and may include processing in parallel or by a subroutine.

The present invention can be utilized in the manufacture how the electric motor to generate a rotating force by a magnetic force.

S200: Coil winding step S202, S420, S520 ... Adhesion step S204, S522 ... Molding jig insertion step S206, S524 ... Introduction step S208 ... Extraction step S210 ... Rotor insertion step 100 ... Electric motor 120 ... Stator 120c ... Slot 120e ... 120 f ... coil 120 h ... inner peripheral surface 122 ... rotor 122a ... outer peripheral surface 124 ... temperature measuring parts 126, 426, 526 ... fixed parts 300, 400, 500 ... molding jigs 302, 402 ... notch part 404 ... groove

Claims (4)

A method of manufacturing an electric motor comprising: an annular stator; and a rotor that is inserted into the stator ring and is rotatably supported in the circumferential direction in a state of being separated from the inner peripheral surface of the stator,
A cylindrical molding jig having an outer diameter smaller than the inner diameter of the stator and having a notch that is an axial notch formed on a part of the outer periphery thereof, and a cross-sectional area smaller than that of the notch and a temperature. A temperature measuring part for measuring the molding jig insertion step of inserting the stator into the stator ring,
An introduction step of introducing a solidified material before solidification into the gap between the molding jig and the stator;
An extraction step of extracting the molding jig from the stator after the solidified material is solidified;
A rotor insertion step of inserting the rotor into the stator ring;
The manufacturing method characterized by having.   The manufacturing method according to claim 1, further comprising an adhesion step of adhering the temperature measurement unit to a surface on the side of the notch portion of the molding jig before the molding jig insertion step. The notch is formed with a groove in the axial direction,
The manufacturing method according to claim 1, wherein, in the molding jig insertion step or the bonding step, the temperature measurement unit is disposed in the groove. A method of manufacturing an electric motor comprising: an annular stator; and a rotor that is inserted into the stator ring and is rotatably supported in the circumferential direction in a state of being separated from the inner peripheral surface of the stator,
A coil is formed by inserting a winding into a slot portion provided in an inner peripheral surface of the stator and extending in the axial direction of the stator, and winding a winding around an intervening portion of the two adjacent slot portions. A coil winding process to generate
An adhesion step of adhering the temperature measuring unit to a side surface of the forming jig;
A molding jig insertion step of inserting a temperature measurement part for measuring temperature into the slot part and a cylindrical molding jig having an outer diameter smaller than the inner diameter of the stator into the stator ring;
An introduction step of introducing a solidified material before solidification into the slot portion;
An extraction step of extracting the molding jig from the stator after the solidified material is solidified;
A rotor insertion step of inserting the rotor into the stator ring;
The manufacturing method characterized by having .

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