JP6315559B2 - Injection molding machine and motor - Google Patents

Description

  The present invention relates to an injection molding machine and a motor.

  An injection molding machine includes a mold clamping device that performs mold opening, mold clamping, and mold closing of a mold device, an injection device that fills a cavity space in the mold device with a molding material, and an ejector device that projects a molded product in the mold device. (For example, refer to Patent Document 1). A mold clamping device, an injection device, an ejector device, etc. have a motor which operates a movable part.

JP 2011-183705 A

  There is a demand for improvement in the performance of motors mounted on machines such as injection molding machines.

  This invention is made | formed in view of the said subject, Comprising: It aims at provision of the injection molding machine which can improve the performance of a motor.

In order to solve the above problems, according to one aspect of the present invention,
An injection molding machine equipped with a motor,
The motor includes a core, an insulator fixed to an end surface of the core, a coil wound around the core and the insulator, an insulating sheet that insulates the core and the coil, and positions of the core and the insulator. Have alignment pins to align,
At least one of the core and the insulator has an insertion groove into which the alignment pin is inserted,
The alignment pin is inserted into the insertion groove together with a part of the insulating sheet, so that the core and the insulator are aligned, and at least one of the core and the insulator is aligned with the alignment. The pin is fixed with the insulating sheet in between ,
The coil is wound around the wall surface of the recess formed in the core and the wall surface of the recess formed in the insulator,
At least one corner of the wall surface of the concave portion of the core and the wall surface of the concave portion of the insulator is formed with a stress relaxation groove having a circular arc shape in cross section for reducing stress generated in the corner portion by winding of the coil,
An injection molding machine is provided in which the insertion groove is the stress relaxation groove, and a gap is formed in the insertion groove in a state where the alignment pin is inserted into the insertion groove .

  According to one aspect of the present invention, an injection molding machine that can improve the performance of a motor is provided.

It is a figure which shows the injection molding machine by one Embodiment of this invention. It is a figure which shows the stator of the mold clamping motor by one Embodiment of this invention. It is sectional drawing along the III-III line of FIG. It is a figure which shows the stator of the mold clamping motor by a 1st modification. It is sectional drawing along the VV line of FIG. It is a figure which fractures | ruptures and shows the insulator of FIG. It is a figure which shows the stator of the mold clamping motor by a 2nd modification.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In each of the drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and description thereof will be omitted.

  FIG. 1 is a view showing an injection molding machine according to an embodiment of the present invention. As shown in FIG. 1, the injection molding machine includes a mold clamping device 10, an injection device 50, and an ejector device 60.

  The mold clamping apparatus 10 performs mold closing, mold clamping, and mold opening of the mold apparatus 30. For example, as shown in FIG. 1, the mold clamping device 10 includes a frame 11, a fixed platen 12, a movable platen 13, a rear platen 15, a tie bar 16, a toggle mechanism 20, and a mold clamping motor 26. In the description of the mold clamping device 10, the moving direction (right direction in FIG. 1) of the movable platen 13 when the mold is closed is referred to as the front, and the moving direction (left direction in FIG. 1) of the movable platen 13 when the mold is opened To do.

  The fixed platen 12 is fixed to the frame 11. A fixed mold 32 is attached to a surface of the fixed platen 12 facing the movable platen 13.

  The movable platen 13 is movable along a guide (for example, a guide rail) 17 laid on the frame 11, and is movable back and forth with respect to the fixed platen 12. A movable mold 33 is attached to the surface of the movable platen 13 facing the fixed platen 12.

  By moving the movable platen 13 back and forth with respect to the fixed platen 12, mold closing, mold clamping, and mold opening are performed. The fixed mold 32 and the movable mold 33 constitute a mold apparatus 30.

  The rear platen 15 is connected to the fixed platen 12 via a plurality of (for example, four) tie bars 16, and is placed on the frame 11 so as to be movable in the mold opening / closing direction. The rear platen 15 may be movable along a guide laid on the frame 11. The guide of the rear platen 15 may be the same as the guide 17 of the movable platen 13.

  In the present embodiment, the fixed platen 12 is fixed to the frame 11 and the rear platen 15 is movable in the mold opening / closing direction with respect to the frame 11, but the rear platen 15 is fixed to the frame 11 and fixed. The platen 12 may be movable in the mold opening / closing direction with respect to the frame 11.

  The tie bar 16 is parallel to the mold opening / closing direction and extends according to the mold clamping force. At least one tie bar 16 is provided with a mold clamping force detector. The mold clamping force detector may be of a strain gauge type, and detects the mold clamping force by detecting tie bar distortion.

  The clamping force detector is not limited to the strain gauge type, and may be a piezoelectric type, a capacitive type, a hydraulic type, an electromagnetic type, or the like, and the mounting position thereof is not limited to the tie bar 16.

  The toggle mechanism 20 is disposed between the movable platen 13 and the rear platen 15, and is attached to the movable platen 13 and the rear platen 15, respectively. As the toggle mechanism 20 expands and contracts in the mold opening and closing direction, the movable platen 13 advances and retreats with respect to the rear platen 15.

  The mold clamping motor 26 moves the movable platen 13 via the toggle mechanism 20. Between the mold clamping motor 26 and the toggle mechanism 20, a ball screw mechanism is provided as a motion conversion unit 27 that converts the rotational motion of the mold clamping motor 26 into a linear motion and transmits the linear motion to the toggle mechanism 20.

  The mold closing is performed by the mold clamping motor 26 moving the movable platen 13 forward. After completion of the mold closing, a mold clamping force is generated by multiplying the propulsive force of the mold clamping motor 26 with the toggle magnification, and the mold clamping is performed by the mold clamping force. A cavity space 34 is formed between the movable mold 33 and the fixed mold 32 during mold clamping, and the cavity space 34 is filled with a liquid molding material. The molding material in the cavity space 34 is solidified and becomes a molded product. Thereafter, the mold clamping motor 26 opens the mold by moving the movable platen 13 backward.

  The injection device 50 fills the mold device 30 with a molding material. The injection device 50 includes a cylinder 51, a screw 52, a metering motor 53, and an injection motor 54. In the description of the injection device 50, unlike the description of the mold clamping device 10, the moving direction of the screw 52 at the time of filling (left direction in FIG. 1) is the front, and the moving direction of the screw 52 at the time of weighing (right direction in FIG. 1). Is described as the rear.

  The cylinder 51 heats the molding material supplied from the supply port 51a. The supply port 51 a is formed at the rear part of the cylinder 51. A heating source such as a heater is provided on the outer periphery of the cylinder 51. A nozzle 56 is provided at the front end of the cylinder 51.

  The screw 52 is disposed in the cylinder 51 so as to be rotatable and reciprocated.

  The metering motor 53 rotates the screw 52 to feed the molding material forward along the spiral groove of the screw 52. The molding material is gradually melted by the heat from the cylinder 51 while being fed forward. As the liquid molding material is fed to the front of the screw 52 and accumulated in the front part of the cylinder 51, the screw 52 is retracted.

  The injection motor 54 advances the screw 52 to fill the cavity space 34 of the mold apparatus 30 with the liquid molding material accumulated in front of the screw 52. Thereafter, the injection motor 54 pushes the screw 52 forward and applies pressure to the molding material in the cavity space 34. The shortage of molding materials due to shorts and sink marks can be replenished.

  In addition, although the injection apparatus of this embodiment is an inline screw system, a pre-plastic system may be used. A pre-plastic injection device supplies a molding material melted in a plasticizing cylinder to the injection cylinder, and injects the molding material from the injection cylinder into a mold device. In the plasticizing cylinder, a screw is rotatably or rotatably and reciprocally disposed, and in the injection cylinder, a plunger is reciprocally disposed. The pre-plastic injection device includes a motor that rotates a screw, a motor that advances and retracts a plunger, and the like.

  The ejector device 60 projects a molded product from the mold device 30 after the mold is opened. The ejector device 60 includes an ejector rod 61 and an ejector motor 62. In the description of the ejector device 60, as in the description of the mold clamping device 10, the moving direction (right direction in FIG. 1) of the movable platen 13 when the mold is closed is the front, and the moving direction of the movable platen 13 when the mold is opened (see FIG. (Left direction in 1) will be described as the rear.

  The ejector rod 61 is inserted into the through hole of the movable platen 13 and can be moved forward and backward with respect to the movable platen 13. As the ejector rod 61 advances and retreats, the protruding member 35 disposed in the movable mold 33 is advanced and retracted, and the protruding member 35 protrudes the molded product from the movable mold 33.

  The ejector motor 62 advances and retracts the ejector rod 61. Between the ejector motor 62 and the ejector rod 61, a motion conversion unit 63 that converts the rotational motion of the ejector motor 62 into the linear motion of the ejector rod 61 is provided. The motion conversion unit 63 is configured by, for example, a ball screw mechanism.

  FIG. 2 is a view showing a stator of a mold clamping motor according to an embodiment of the present invention. FIG. 3 is a cross-sectional view taken along line III-III in FIG. In FIG. 2, illustration of a coil is abbreviate | omitted for convenience of explanation.

  The stator 70 includes a split core 71, an insulator 72, a coil 73 (see FIG. 3), an insulating sheet 74, and an alignment pin 75 (see FIG. 3). The alignment pin 75 corresponds to the alignment member described in the claims.

  The split core 71 is made of a magnetic material, and may be formed by laminating electromagnetic steel plates in the motor axial direction (left-right direction in FIG. 2) in order to reduce eddy current loss. Concave portions 71a are formed on both side surfaces (divided surfaces) of the split core 71, and a coil 73 is wound around the wall surface of the concave portion 71a.

  The insulators 72 are respectively fixed to both end surfaces of the split core 71 in the motor axial direction, and a plurality (only one is shown in FIG. 2) is used. Concave portions 72a are formed on the three sides of each insulator 72, ie, both side surfaces and end surfaces (end surfaces opposite to the split core 71), and a coil 73 is wound around the wall surface of the concave portion 72a.

  The wall surface of the recess 71a of the split core 71 and the wall surface of the recess 72a of the insulator 72 are formed continuously. An annular groove is formed by the recesses 72 a of the plurality of insulators 72 and the recesses 71 a of the split core 71.

  The coil 73 is wound around the split core 71 and the insulator 72. The winding method of the coil 73 may be concentrated winding. When a ring-shaped core is used instead of the split core 71, the coil may be wound by either concentrated winding or distributed winding.

  The alignment pin 75 is used for alignment of the split core 71 and the insulator 72. The alignment pin 75 is formed integrally with the insulator 72 and is inserted into the insertion groove 76 formed in the split core 71. The insertion groove 76 corresponds to the insertion portion described in the claims.

  As shown in FIG. 3, the alignment pin 75 and the insertion groove 76 are formed so as not to protrude from the wall surface of the concave portion 71 a of the split core 71 in order to secure an installation space for the coil 73. The cross-sectional shape of the alignment pin 75 may be circular, and the cross-sectional shape of the insertion groove 76 may be a shape in which a part of the circle is missing. The diameter of the alignment pin 75 may be smaller than the diameter of the insertion groove 76.

  A plurality (four in FIG. 3) of alignment pins 75 may be formed, and a plurality of insertion grooves 76 may be formed corresponding to the plurality of alignment pins 75. The interval between the alignment pins 75 before being inserted into the insertion groove 76 may be narrower than the interval between the insertion grooves 76. The split core 71 and the insulator 72 can be fixed by press-fitting the alignment pin 75 into the insertion groove 76.

  Note that the diameter of the alignment pin 75 before being inserted into the insertion groove 76 may be slightly larger than the diameter of the insertion groove 76. The alignment pin 75 can be press-fitted into the insertion groove 76. In this case, the cross-sectional shape of the alignment pin 75 may be a shape in which a part of the circle is missing so that the alignment pin 75 does not protrude from the wall surface of the recess 71a. The cross-sectional shape of the alignment pin 75 may be an elliptical shape, and is not particularly limited.

  The insertion groove 76 may be formed in parallel with the motor axial direction and may extend from one end of the split core 71 to the other end. The insertion groove 76 can be formed by laminating electromagnetic steel plates having the same shape in the motor axial direction.

  The insertion groove 76 only needs to be able to insert the alignment pin 75, and the length of the insertion groove 76 is not particularly limited. For example, the insertion groove 76 may be formed only at the end of the split core 71.

  As shown in FIG. 3, the alignment pin 75 is inserted into the insertion groove 76 together with a part of the insulating sheet 74. Thereby, alignment with the split core 71 and the insulator 72 is performed, and the wall surface of the recessed part 71a of the split core 71 and the wall surface of the recessed part 72a of the insulator 72 are flush. At the same time, the split core 71 and the alignment pin 75 are fixed with the insulating sheet 74 interposed therebetween. By inserting the alignment pin 75 into the insertion groove 76, alignment of the split core 71 and the insulator 72 and fixing of the insulating sheet 74 are performed, so that assembly workability of the stator 70 is good. Further, since the alignment pin 75 presses the insulating sheet 74 against the split core 71 so as to be in close contact, the heat of the coil 73 easily escapes to the split core 71 via the insulating sheet 74. The temperature rise of the coil 73 can be suppressed, and the rated torque can be increased. Since the motor of an injection molding machine requires a magnitude of torque rather than the magnitude of the rotation speed, it is effective that the torque is large.

  The insertion groove 76 may be formed anywhere on the wall surface of the recess 71a, but may be formed at a corner of the recess 71a. The adhesion of the insulating sheet 74 is good at the corner where the shape of the wall surface of the recess 71a changes, and the heat dissipation is good.

  FIG. 4 is a view showing a stator of a mold clamping motor according to a first modification. FIG. 5 is a cross-sectional view taken along the line VV in FIG. FIG. 6 is a diagram showing the insulator of FIG. 4 in a broken view. In FIG. 4, illustration of a coil is abbreviate | omitted for convenience of explanation.

  In the first modification, the alignment pin 75A (see FIG. 5) is formed integrally with the split core 71 and is inserted into an insertion groove 76A formed in the insulator 72. A part of the insulating sheet 74A is inserted into the insertion groove 76A together with the alignment pin 75A.

  The insulating sheet 74 </ b> A protrudes from the split core 71 to the insulator 72 side and covers the joint between the split core 71 and the insulator 72. A cut is formed in the insulating sheet 74A, and the alignment pin 75A passes through the cut.

  The alignment pin 75A projects from the split core 71 toward the insulator 72, passes through the cut of the insulating sheet 74A, and presses the insulating sheet 74A against the insulator 72. The cut may be filled with an insulating material such as resin.

  As described above, the alignment pin 75A is inserted into the insertion groove 76A together with a part of the insulating sheet 74A. Thereby, alignment with the split core 71 and the insulator 72 is performed, and the wall surface of the recessed part 71a of the split core 71 and the wall surface of the recessed part 72a of the insulator 72 are flush. At the same time, the insulator 72 and the alignment pin 75A are fixed with the insulating sheet 74A interposed therebetween.

  By inserting the alignment pin 75A into the insertion groove 76A, alignment of the split core 71 and the insulator 72 and fixing of the insulating sheet 74A are performed, so that assembly workability is good. Further, since the alignment pin 75A presses the insulating sheet 74A against the insulator 72 to bring it into intimate contact, the insulating sheet 74A is in intimate contact with the split core 71, and the heat of the coil 73 is applied to the split core 71 via the insulating sheet 74A. Easy to escape. The temperature rise of the coil 73 can be suppressed, and the rated torque can be increased. Since the motor of an injection molding machine requires a magnitude of torque rather than the magnitude of the rotation speed, it is effective that the torque is large.

  The insertion groove 76A may be formed anywhere on the wall surface of the recess 72a, but may be formed at a corner of the recess 72a as shown in FIG. The adhesiveness of the insulating sheet 74A is good at the corner where the shape of the wall surface of the recess 72a changes, and the heat dissipation is good.

  By the way, when the coil is wound, a force for expanding the recess 72a is generated as indicated by an arrow in FIG. 6, and a large stress is generated at the corner of the recess 72a. The greater the number of turns of the coil 73, the greater the stress generated at the corner of the recess 72a.

  The insertion groove 76A functions as a stress relaxation groove that reduces the stress generated in the corner by being formed in the corner of the recess 72a. The stress relaxation groove may include a curved portion such as an arc shape or an elliptic arc shape in a cross-sectional view. Note that the stress relaxation groove may include an obtuse polygonal line portion in a cross-sectional view. It is sufficient that the maximum stress generated in the corner portion is reduced as compared with the case where the stress relaxation groove is not formed.

  By forming the stress relaxation groove in the resin insulator 72 having a lower breaking strength than that of the metal split core 71, the insulator 72 can be prevented from being damaged when the coil is wound. Further, the number of turns of the coil 73 can be increased, and the torque can be increased. Since the motor of an injection molding machine requires a magnitude of torque rather than the magnitude of the rotation speed, it is effective that the torque is large. A convex stress relaxation portion may be formed instead of the concave stress relaxation groove, but in this case, the installation space of the coil 73 is narrowed.

  FIG. 7 is a view showing a stator of a mold clamping motor according to a second modification. In FIG. 7, illustration of a coil is abbreviate | omitted for convenience of explanation.

  In the second modification, the alignment pin 75B is separated from the split core 71 and the insulator 72, and both an insertion groove (not shown) formed in the split core 71 and an insertion groove 76B formed in the insulator 72 are provided. Inserted into. A part of the insulating sheet 74B is inserted into the insertion groove 76B or the like.

  The insulating sheet 74 </ b> B protrudes from the split core 71 toward the insulator 72, and covers the joint between the split core 71 and the insulator 72.

  Unlike the first modification, an alignment pin 75B is disposed on the opposite side of both the split core 71 and the insulator 72 with the insulating sheet 74B as a reference. Therefore, the insulating sheet 74B does not need to be cut.

  As described above, the alignment pin 75B is inserted into the insertion groove 76B together with a part of the insulating sheet 74B. Thereby, alignment with the split core 71 and the insulator 72 is performed, and the wall surface of the recessed part 71a of the split core 71 and the wall surface of the recessed part 72a of the insulator 72 are flush. At the same time, each of the split core 71 and the insulator 72 and the alignment pin 75B are fixed with the insulating sheet 74B interposed therebetween.

  By inserting the alignment pin 75B into the insertion groove 76B, the alignment of the split core 71 and the insulator 72 and the fixing of the insulating sheet 74B are performed, so that the assembly workability is good. In addition, since the alignment pin 75B presses the insulating sheet 74B against both the split core 71 and the insulator 72 to bring them into close contact with each other, the heat of the coil 73 easily escapes to the split core 71 and the like via the insulating sheet 74B. The temperature rise of the coil 73 can be suppressed, and the rated torque can be increased. Since the motor of an injection molding machine requires a magnitude of torque rather than the magnitude of the rotation speed, it is effective that the torque is large.

  The insertion groove 76B may be formed anywhere on the wall surface of the recess 72a, but may be formed at a corner of the recess 72a. At the corner where the shape of the wall surface of the recess 72a changes, the adhesiveness of the insulating sheet 74B is good and the heat dissipation is good.

  By the way, when the coil is wound, a force for expanding the recess 72a is generated as indicated by an arrow in FIG. 6, and a large stress is generated at the corner of the recess 72a. The greater the number of turns of the coil 73, the greater the stress generated at the corner of the recess 72a.

  The insertion groove 76B functions as a stress relaxation groove that reduces stress generated in the corner by being formed in the corner of the recess 72a. The damage of the insulator 72 at the time of coil winding can be suppressed. Further, the number of turns of the coil 73 can be increased, and the torque can be increased. Since the motor of an injection molding machine requires a magnitude of torque rather than the magnitude of the rotation speed, it is effective that the torque is large.

  The embodiments of the injection molding machine and the like have been described above. However, the present invention is not limited to the above-described embodiments and the like, and various modifications can be made within the scope of the gist of the present invention described in the claims. Improvements are possible.

  For example, although the structure shown in FIGS. 2-7 is applied to a stator, it may be applied to a rotor. The structure shown in FIGS. 2 to 7 is applied to the mold clamping motor 26, but may be applied to a measuring motor 53, an injection motor 54, an ejector motor 62, and the like. Moreover, although the structure shown in FIGS. 2-7 is applied to the motor mounted in an injection molding machine, you may apply to the motor mounted in machines other than an injection molding machine.

  2 and 3 may protrude from the split core 71 to the insulator 72 side and cover the joint between the split core 71 and the insulator 72 as in the first modification. In this case, a cut is formed in the insulating sheet 74, and the alignment pin 75 passes through the cut. The alignment pin 75 protrudes from the insulator 72 toward the split core 71, passes through the cut of the insulating sheet 74, and presses the insulating sheet 74 against the split core 71. The cut may be filled with an insulating material such as resin.

10 Mold clamping device 11 Frame 12 Fixed platen 13 Movable platen 26 Mold clamping motor 30 Mold device 32 Fixed mold 33 Movable mold 34 Cavity space 50 Injection device 51 Cylinder 52 Screw 53 Metering motor 54 Injection motor 56 Nozzle 60 Ejector device 61 Ejector rod 62 Ejector motor 70 Stator 71 Split core 72 Insulator 73 Coil 74 Insulating sheet 75 Positioning pin 76 Insertion groove

Claims (6)

An injection molding machine equipped with a motor,
The motor includes a core, an insulator fixed to an end surface of the core, a coil wound around the core and the insulator, an insulating sheet that insulates the core and the coil, and positions of the core and the insulator. Have alignment pins to align,
At least one of the core and the insulator has an insertion groove into which the alignment pin is inserted,
The alignment pin is inserted into the insertion groove together with a part of the insulating sheet, so that the core and the insulator are aligned, and at least one of the core and the insulator is aligned with the alignment. The pin is fixed with the insulating sheet in between ,
The coil is wound around the wall surface of the recess formed in the core and the wall surface of the recess formed in the insulator,
At least one corner of the wall surface of the concave portion of the core and the wall surface of the concave portion of the insulator is formed with a stress relaxation groove having a circular arc shape in cross section for reducing stress generated in the corner portion by winding of the coil,
The insertion groove is the stress relaxation groove, and a gap is formed in the insertion groove in a state in which the alignment pin is inserted into the insertion groove . The injection molding machine according to claim 1 , wherein the stress relaxation groove is formed at a corner of the wall surface of the recess of the insulator. The injection molding machine according to claim 2, wherein the insertion groove is the stress relaxation groove formed in a corner portion of the wall surface of the concave portion of the insulator . Core, insulator fixed to end surface of core, coil wound around core and insulator, insulating sheet for insulating core and coil, and alignment pin for aligning positions of core and insulator Have
At least one of the core and the insulator has an insertion groove into which the alignment pin is inserted,
The alignment pin is inserted into the insertion groove together with a part of the insulating sheet, so that the core and the insulator are aligned, and at least one of the core and the insulator is aligned with the alignment. The pin is fixed with the insulating sheet in between ,
The coil is wound around the wall surface of the recess formed in the core and the wall surface of the recess formed in the insulator,
At least one corner of the wall surface of the concave portion of the core and the wall surface of the concave portion of the insulator is formed with a stress relaxation groove having a circular arc shape in cross section for reducing stress generated in the corner portion by winding of the coil,
The motor, wherein the insertion groove is the stress relaxation groove, and a gap is formed in the insertion groove in a state where the alignment pin is inserted into the insertion groove . The motor according to claim 4 , wherein the stress relaxation groove is formed at a corner of the wall surface of the recess of the insulator. The motor according to claim 5 , wherein the insertion groove is the stress relaxation groove formed at a corner of the wall surface of the recess of the insulator .

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