Apparatus for molding hairpin

Abstract

An apparatus for molding a hairpin inserted into a stator core includes a clamping unit including a connection bracket mounted on a front end of a robot arm and at least one clamper mounted on the connection bracket and configured to be reciprocally driven in opposite directions in a straight line, and a mold unit detachably coupled with the at least one clamper and configured to press mold a head portion of the hairpin by a molding jig configured to be driven by the at least one clamper.

Claims

1. An apparatus for molding a hairpin inserted into a stator core, the apparatus comprising: a clamping unit including a connection bracket mounted on a front end of a robot arm and at least one clamper mounted on the connection bracket and configured to be reciprocally driven in opposite directions in a straight line; and a mold unit detachably coupled with the at least one clamper and configured to press mold a head portion of the hairpin by a molding jig configured to be driven by the at least one clamper.

2. The apparatus of claim 1, wherein: the at least one clamper comprises a pair of clampers, each of which comprises a first end mounted on the connection bracket and a second end on which a fitting end protrudes; and the pair of clampers is configured to reciprocate to become closer and farther with reference to a central portion of the connection bracket.

3. The apparatus of claim 2, wherein the fitting end is slidably inserted into a mounting slot formed in the molding jig.

4. The apparatus of claim 2, wherein the mold unit is detachably coupled with the connection bracket at a position between the pair of clampers by a fixing chuck.

5. The apparatus of claim 4, wherein the fixing chuck comprises: a fixing block mounted on the connection bracket; and a plurality of fixing pins disposed along an exterior circumference of the fixing block, and configured to be inserted into the fixing block and to protrude from the fixing block.

6. The apparatus of claim 4, wherein the mold unit comprises: a fixing plate coupled to the connection bracket through the fixing chuck; a support bar fixed to the fixing plate; and at least one molding jig coupled with the at least one clamper and configured to be driven by the at least one clamper to move along the support bar to mold the head portion of the hairpin.

7. The apparatus of claim 6, wherein: the at least one molding jig comprises a first jig and a second jig coupled with the at least one clamper; and the first jig and the second jig are configured to move to be closer or farther along a guide bar.

8. An apparatus for molding a hairpin inserted into a stator core, the apparatus comprising: a clamping unit including a connection bracket mounted on a front end of a robot arm and a pair of clampers mounted on the connection bracket and configured to be reciprocally driven in opposite directions in a straight line, wherein each clamper of the pair of clampers comprises a first end mounted on the connection bracket and a second end on which a fitting end protrudes; and a mold unit detachably coupled with the connection bracket at a position between the pair of clampers by a fixing chuck, detachably coupled with the pair of clampers, and configured to press mold a head portion of the hairpin by a pair of molding jigs configured to be driven by the pair of clampers.

9. The apparatus of claim 8, wherein the pair of clampers is configured to reciprocate to become closer and farther with reference to a central portion of the connection bracket.

10. The apparatus of claim 8, wherein: each molding jig of the pair of molding jigs comprises a mounting slot; and the fitting ends of the pair of clampers are slidably inserted into the mounting slots.

11. The apparatus of claim 8, wherein the fixing chuck comprises: a fixing block mounted on the connection bracket; and a plurality of fixing pins disposed along an exterior circumference of the fixing block, and configured to be inserted into the fixing block and to protrude from the fixing block.

12. The apparatus of claim 8, wherein the mold unit comprises: a fixing plate coupled to the connection bracket through the fixing chuck; and a support bar fixed to the fixing plate, wherein the pair of molding jigs is configured to be driven by the pair of clampers to move along the support bar to mold the head portion of the hairpin.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 schematically illustrates a structure of a hairpin winding type stator of a drive motor applied to an exemplary embodiment.

(2) FIG. 2 is a perspective view of an apparatus for molding hairpins according to an exemplary embodiment.

(3) FIG. 3 illustrates an operation of an apparatus for molding hairpins according to an exemplary embodiment.

(4) FIG. 4 is a perspective view of an apparatus for molding hairpins according to an exemplary embodiment.

(5) FIG. 5, which includes FIGS. 5A and 5B, illustrates an operation of an apparatus for molding hairpins according to an exemplary embodiment.

(6) FIG. 6 and FIG. 7 sequentially illustrate a method for inserting hairpins by using an apparatus for molding hairpins according to an exemplary embodiment.

(7) The following reference numerals can be used in conjunction with the drawings: 1: stator 3: stator core 5: slot 7: coil 9: dummy core 10: hairpin 11: head portion 13: leg portion 15: decoated portion 20: clamping unit 21: robot arm 23: connection bracket 25: clamper 27: driving portion 29: fitting end 30: fixing indentation 31: fixing chuck 33: fixing block 35: fixing pin 40: mold unit 41: fixing plate 43: mounting hole 45: support bar 47: guide bar 50: molding jig 51: first jig 53: second jig 55: mounting slot 57: molding surface 60: uncoiler 70: heating device 80: bending device 90: cutting device 100: molding apparatus 110: extracting gripper unit

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

(8) Hereinafter, the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

(9) In order to clarify embodiments of the present invention, parts that are not connected to the description will be omitted, and the same elements or equivalents are referred to with the same reference numerals throughout the specification.

(10) In the following description, dividing names of components into first, second, and the like is to divide the names because the names of the components are the same as each other, and an order thereof is not particularly limited.

(11) FIG. 1 schematically illustrates a structure of a hairpin winding type stator of a drive motor applied to an exemplary embodiment.

(12) Referring to FIG. 1, a hairpin winding type stator 1 of a drive motor applied to an exemplary embodiment may be applied to a drive motor for an electric vehicle such as a hybrid electric vehicle that outputs driving torque from electrical energy.

(13) Such a drive motor includes a stator 1, a rotor (not shown) disposed with a certain gap with the stator 1, and a plurality of permanent magnets (not shown) installed on the rotor.

(14) The stator 1 includes a stator core 3 formed as a stack of a plurality of electrical steel sheets, and stator coils (hereinafter called hairpins) 10 of a hairpin type are wound on the stator core 3 through a plurality of slots 5.

(15) In addition, the rotor includes a rotor core formed as a stack of a plurality of electrical steel sheets in an axial direction, and the permanent magnet is installed by being inserted in insertion holes provided in the rotor core.

(16) In addition, the hairpins 10 are flat coils, having a pair of leg portions 13 on both sides of a head portion 11, and are generally U-shaped or V-shaped. The hairpins 10 may be formed as flat coils of a square cross-section.

(17) The hairpins 10 are inserted into the predetermined layer (indicated by dotted lines in the drawing) of a slot 5 in the stator core 3. At this time, decoated portions 15 formed at ends of the pair of leg portions 13 protrudes exteriorly from the slot 5 to be exposed below a bottom of the stator core 3, and the decoated portions 15 are welded to form an electrically connected coil winding.

(18) Although it is described above that an exemplary embodiment of the present invention is applied to the stator 1 of a hairpin winding type for a drive motor, the scope of the present invention is not necessarily limited thereto. It may be understood that the technical disclosure of an exemplary embodiment may be applied to a drive motor having the hairpins 10 of various types and uses.

(19) FIG. 2 is a perspective view of an apparatus for molding hairpins according to an exemplary embodiment. FIG. 3 illustrates an operation of an apparatus for molding hairpins according to an exemplary embodiment. FIG. 4 is a perspective view of an apparatus for molding hairpins according to an exemplary embodiment. FIG. 5, which includes FIGS. 5A and 5B, illustrates an operation of an apparatus for molding hairpins according to an exemplary embodiment.

(20) An apparatus for molding hairpins and a method of inserting a hairpin using the same according to an exemplary embodiment unwinds a coil 7 spiral-wound on an uncoiler 60, molds the coil 7 into the hairpins 10 each having the head portion 11, and then inserts the hairpins 10 into the stator core 3, thereby achieving automation of an overall process.

(21) For such a purpose, an apparatus 100 for molding hairpins according to an exemplary embodiment includes a clamping unit 20 and a mold unit 40.

(22) Referring to FIG. 2, the clamping unit 20 is configured at a front end of a multi-axis robot arm 21.

(23) The clamping unit 20 includes a connection bracket 23 mounted on the front end of the robot arm 21.

(24) A pair of clampers 25 is mounted on the connection bracket 23.

(25) The pair of clampers 25 is reciprocally driven in opposite directions in a straight line.

(26) That is, the pair of clampers 25 is formed in a lengthy rod shape, where first ends of the clampers 25 are mounted on the connection bracket 23, and may reciprocate to become closer and farther with reference to a central portion of the connection bracket 23.

(27) At this time, a driving portion 27 driving the pair of clampers 25 may be operated by a pneumatic cylinder.

(28) Alternatively, the pair of clampers 25 may be operated by a drive motor.

(29) The pair of clampers 25 respectively includes second ends facing each other, and a fitting end 29 protrudes on each facing surface of the second ends.

(30) The mold unit 40 is detachably fitted to the fitting end 29.

(31) At this time, the mold unit 40 is detachably coupled with the connection bracket 23 at a position between the pair of clampers 25, by a fixing chuck 31.

(32) Referring to FIG. 3, the fixing chuck 31 includes a fixing block 33 and a fixing pin 35. The fixing block 33 is mounted on a fixing indentation 30 of the connection bracket 23. A plurality of the fixing pins 35 may be disposed along an exterior circumference of the fixing block 33, and may operate to be inserted into the fixing block 33 (refer to the drawing on the left in FIG. 3) and protrude from the fixing block 33 (refer to the drawing on the right in FIG. 3).

(33) The fixing pin 35 has a basic state of being inserted into the fixing block 33, and for coupling to the mold unit 40, protrudes from the fixing block 33 to be coupled with a mounting hole 43 of the mold unit 40.

(34) The fixing pin 35 of the fixing chuck 31 may be pneumatically operated.

(35) Meanwhile, referring to FIG. 4, the mold unit 40 fixed to the connection bracket 23 through the fixing chuck 31 incudes a fixing plate 41, a plurality of support bars 45, and a pair of molding jigs 50.

(36) In more detail, the mold unit 40 is coupled to the fixing chuck 31 through the fixing plate 41.

(37) The fixing plate 41 is formed with the mounting hole 43 for coupling to the fixing chuck 31.

(38) The mounting hole 43 is formed as a hole that may be coupled with the fixing block 33 and the fixing pin 35 installed on the fixing block 33.

(39) In addition, the plurality of support bars 45 are fixed to the fixing plate 41 and the fixing plate 41 is mounted with the pair of molding jigs 50 through the plurality of support bars 45.

(40) The pair of molding jigs 50 includes a first jig 51 and a second jig 53. The first jig 51 and the second jig 53 are slidably coupled with the support bar 45, supported by a plurality of guide bars 47, and reciprocally driven in a straight line along the guide bars 47.

(41) In addition, each of the first jig 51 and the second jig 53 is formed with a mounting slot 55 into which the fitting end 29 of the pair of clampers 25 may be slidably inserted.

(42) That is, the mold unit 40 is mounted on the clamping unit 20 through the fixing chuck 31 while the fitting end 29 is inserted into the mounting slot 55.

(43) Referring to FIGS. 5A and 5B, by the operation of the pair of clampers 25, the first jig 51 and the second jig 53 in the mold unit 40 may become closer or farther and may be brought tightly close together to form the coil 7 therebetween.

(44) At this time, the first jig 51 and the second jig 53 move along the guide bar 47.

(45) Molding surfaces 57 of the first jig 51 and the second jig 53 are formed in shapes corresponding to a desired shape of the head portion 11 of the hairpins 10.

(46) That is, according to an apparatus 100 for molding hairpins according to an exemplary embodiment, the mold unit 40 may be replaced from the clamping unit 20 according to a desired shape of the head portion 11 of the hairpins 10.

(47) The hairpins 10 molded by using an apparatus 100 for molding hairpins may be inserted into the stator core 3 as follows.

(48) FIG. 6 and FIG. 7 illustrate a sequential method for inserting hairpins by using an apparatus for molding hairpins according to an exemplary embodiment.

(49) Referring to FIG. 6, according to an inserting method of hairpins according to an exemplary embodiment of the present invention, the spiral-wound coil on the uncoiler 60 is unwound first.

(50) At this time, the coil is coated with an insulating film of an enamel material on a copper wire.

(51) Subsequently, the coil is supplied to a heating device 70.

(52) The heating device 70 is a device that heats the coil and peels off the insulating film of the enamel material.

(53) A predetermined portion of the coil is decoated by the heating device 70 to form the decoated portion 15 on the coil.

(54) Subsequently, the coil having the decoated portion 15 is supplied to a bending device 80.

(55) The bending device 80 forms a leg portion 13 and the head portion 11 in the coil.

(56) At this time, the bending device 80 may include a computerized numerical control (CNC) bending device, or a press bending device.

(57) The CNC bending device and the press bending device may be implemented as known in the art.

(58) The bending device 80 is to bend the coil in multiple stages to two-dimensionally form the leg portion 13 and the head portion 11.

(59) The coil formed with the leg portion 13 and the head portion 11 is cut by a predetermined length by using a cutting device 90.

(60) The hairpins 10 are formed in a shape having two leg portions 13 at both sides of the head portion 11.

(61) Here, the decoated portion 15 is formed at the distal end of each leg portion 13 from the head portion 11.

(62) The hairpins 10 may be welded at the decoated portions 15 after being inserted into the stator core 3.

(63) Subsequently, the head portion 11 is molded by the mold unit 40 of a molding apparatus 100.

(64) In more detail, the mold unit 40 corresponding to a desired shape of the head portion 11 is loaded on the clamping unit 20.

(65) That is, while the molding jig 50 is inserted into the pair of clampers 25, the fixing block 33 is coupled with the fixing chuck 31 of the connection bracket 23.

(66) The head portion 11 that has been two-dimensionally formed at the bending device 80 is interposed between the first jig 51 and the second jig 53.

(67) The first jig 51 and the second jig 53 are brought tightly close together by the pair of clampers 25, and thereby the head portion 11 is three-dimensionally formed.

(68) At this time, the molding apparatus 100 molds the hairpins 10 and simultaneously, the molding apparatus 100 moves the molded hairpins 10 to be inserted into the stator core while molding the hairpins 10.

(69) For example, the molding apparatus 100 may mold the hairpins 10 and simultaneously may insert the molded hairpins 10 into the slot 5 of the stator core 3.

(70) Alternatively, referring to FIG. 7, the molding apparatus 100 may mold the hairpins 10 and align the molded hairpins 10 into a dummy core 9 at the same time, and then may simultaneously insert the hairpins 10 aligned in the dummy core 9 into the stator core 3 by an extracting gripper unit 110.

(71) Therefore, according to an apparatus for molding hairpins and a method of inserting a hairpin using the same according to an exemplary embodiment, molding the hairpins 10 and inserting the molded hairpins may be simultaneously performed by using the molding apparatus 100, thereby improving productivity by reducing an overall cycle time.

(72) That is, according to an apparatus for molding a hairpin and a method of inserting a hairpin using the same, full automation from molding of the hairpins 10 to inserting the molded hairpins into the stator core may be enabled.

(73) In addition, according to an apparatus for molding hairpins and a method of inserting a hairpin using the same according to an exemplary embodiment, a loading space for loading molded hairpins and a carrier or moving system for the loaded hairpins may be removed, thereby minimizing a work space and reducing investment cost.

(74) In addition, according to an apparatus for molding hairpins and a method of inserting a hairpin using the same according to an exemplary embodiment, depending on a desired shape of the head portion 11 of the hairpins 10 to be molded, the mold unit 40 may be easily replaced in the clamping unit 20, thereby being capable of handling various types.

(75) While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.