JP6193146B2 - Method for measuring parallelism of injection molding machine, measuring device for injection molding machine, and injection molding machine - Google Patents

Description

  The present invention relates to a parallelism measuring method for an injection molding machine, a parallelism measuring device for an injection molding machine, and an injection molding machine.

  An injection molding machine molds a molded product by filling a cavity space in a mold apparatus in a mold-clamped state with a liquid molding material and solidifying the filled molding material (see, for example, Patent Document 1). The mold apparatus includes a fixed mold and a movable mold. The fixed mold is attached to the fixed platen, and the movable mold is attached to the movable platen. The injection molding machine performs mold closing, mold clamping, and mold opening by moving the movable platen back and forth with respect to the fixed platen.

JP 2008-238742 A

  Conventionally, a displacement sensor attached to the tip of a rod has been used to measure the parallelism of two members (for example, a fixed platen and a movable platen) of an injection molding machine. Since the posture of the rod is not stable and the measurement direction of the displacement sensor is not stable, the measurement accuracy is poor.

  The present invention has been made in view of the above problems, and has as its main object to provide a method for measuring the parallelism of an injection molding machine with improved measurement accuracy.

In order to solve the above problems, according to one aspect of the present invention,
A measuring device of an injection molding machine that measures a linear distance between a first member and a second member,
A measurement unit that contacts the first member and measures a linear distance between the first member and the second member;
A base portion that determines the posture of the measuring portion relative to the second member by contacting the second member ;
There is provided a measuring apparatus for an injection molding machine that includes a position adjusting unit that connects the base unit and the measuring unit and adjusts the position of the measuring unit with respect to the base unit in the measuring direction of the measuring unit.

  According to one aspect of the present invention, a method for measuring the parallelism of an injection molding machine with improved measurement accuracy is provided.

It is a figure which shows the state at the time of mold opening completion of the injection molding machine by one Embodiment of this invention. It is a figure which shows the state at the time of the completion | finish of mold closing of the injection molding machine by one Embodiment of this invention. It is a figure which shows the parallelism measuring apparatus of the injection molding machine by one Embodiment of this invention.

  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 a state at the completion of mold opening of an injection molding machine according to an embodiment of the present invention. FIG. 2 is a view showing a state at the completion of mold closing of the injection molding machine according to the embodiment of the present invention. Hereinafter, the moving direction of the movable platen 13 when the mold is closed (right direction in FIGS. 1 and 2) is assumed to be the front, and the moving direction of the movable platen 13 when the mold is opened (left direction in FIGS. 1 and 2) is assumed to be the rear. To do.

  For example, as shown in FIG. 1, the injection molding machine 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, a mold clamping motor 26, and a control device 80.

  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 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 able to advance and retreat. 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 forward and backward with respect to the frame 11. However, the rear platen 15 is fixed to the frame 11, and the fixed platen 12 is fixed to the frame 11. 11 may be freely advanced and retracted.

  The tie bar 16 is parallel to the mold opening / closing direction and extends according to the mold clamping force. A mold clamping force sensor 18 is provided on at least one tie bar 16. The mold clamping force sensor 18 is, for example, a strain sensor, detects an actual value of the mold clamping force by detecting distortion of the tie bar 16, and outputs a signal indicating the actual value to the control device 80. The control device 80 performs feedback control so that the deviation between the actual value of the mold clamping force and the set value becomes zero.

  The mold clamping force sensor 18 is not limited to a strain sensor that detects the strain of the tie bar 16. For example, a load cell may be used as the mold clamping force sensor.

  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 drives 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 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 clamping motor 26 has an encoder 26a. The encoder 26 a detects the actual value of the rotation angle of the output shaft of the mold clamping motor 26 and outputs a signal indicating the actual value to the control device 80. The control device 80 performs feedback control so that the deviation between the actual value of the rotation angle and the set value becomes zero.

  The control device 80 includes a storage unit such as a memory and a CPU, and controls the mold clamping motor 26 by causing the CPU to execute a control program stored in the storage unit.

  In the mold closing process, the mold clamping motor 26 is driven to operate the toggle mechanism 20 and the movable platen 13 is advanced. The movable mold 33 approaches the fixed mold 32.

  In the mold clamping process, the mold clamping motor 26 is driven in a state where the movable mold 33 and the fixed mold 32 are in contact with each other, and a mold clamping force obtained by multiplying the propulsive force by the mold clamping motor 26 with a toggle magnification is generated. A cavity space is formed between the fixed mold 32 and the movable mold 33 in the clamped state. A molded product is molded by filling the cavity space with a liquid molding material and solidifying the filled molding material.

  In the mold opening process, the mold clamping motor 26 is driven to operate the toggle mechanism 20, and the movable platen 13 is moved backward. After the mold is opened, the molded product is ejected from the mold apparatus 30.

  The injection molding machine 10 may have a hydraulic cylinder instead of the mold clamping motor 26 as a drive unit for the movable platen 13. The injection molding machine 10 may have a linear motor for opening and closing the mold and an electromagnet for clamping. When the mold clamping force is generated by the attractive force of the electromagnet, a magnetic sensor that detects the strength of the magnetic field around the electromagnet may be used as the mold clamping force sensor. In the present embodiment, a mold clamping force is generated by multiplying the propulsive force of the mold clamping motor 26 by the toggle magnification. However, the toggle mechanism 20 is not necessary, and the propulsive force of the mold clamping motor 26 is not amplified and is moved as it is. 13 may be transmitted.

  FIG. 3 is a view showing a parallelism measuring device for an injection molding machine according to an embodiment of the present invention. The parallelism measuring device 40 measures the parallelism between the first member and the second member. One of the first member and the second member may be the fixed platen 12 and the other may be the movable platen 13.

  The combination of the first member and the second member is not particularly limited. For example, one of the first member and the second member may be the rear platen 15 and the other may be the movable platen 13. One of the first member and the second member may be a fixed mold 32 and the other may be a movable mold 33.

  The parallelism measuring device 40 includes a measuring unit 50, a base unit 60, and a position adjusting unit 70.

  The measuring unit 50 measures a linear distance between the first member and the second member. The straight line distance may be a difference from a predetermined reference.

  The measurement unit 50 may be a contact type, and includes, for example, a movable unit 51, a guide unit 52, a displacement sensor unit 53, and an urging unit 54.

  The movable portion 51 is movable with respect to the base portion 60 and is not rotatable. The movable part 51 is movable along the guide part 52. The movable part 51 may be movable and rotatable with respect to the base part 60, and the movable part 51 and the guide part 52 may be screwed together.

  The movable part 51 may have a ball 55 as a contact that contacts the first member. Although a cone may be used instead of the ball 55, damage due to contact can be suppressed as compared to the case where a cone is used.

  The movable portion 51 has a ball holder 56 that holds the ball 55. The ball holder 56 may hold the ball 55 rotatably. The ball 55 is rotatable around its center. Friction between the ball 55 and the first member can be reduced, and the measurement position can be easily changed.

  The displacement sensor unit 53 measures the amount of displacement from the reference position of the movable unit 51 when the movable unit 51 and the first member are in contact with each other. By measuring the amount of displacement of the movable portion 51 by changing the measurement position, the variation in the linear distance between the first member and the second member can be measured, and the parallelism between the first member and the second member can be measured. It can be measured.

  The urging unit 54 urges the movable unit 51 toward the reference position. The urging portion 54 may be constituted by a spring, for example, and urges the movable portion 51 toward the reference position by the elastic restoring force of the spring. The measurement position can be changed while pressing the movable portion 51 against the first member.

  In addition, although the measurement part 50 of this embodiment is a contact type, a non-contact type may be sufficient and it is not necessary to have the movable part 51 in the case of a non-contact type. In the case of the non-contact type, the displacement sensor unit 53 is not particularly limited, but may be any of an optical type, an ultrasonic type, an eddy current type, and a capacitance type.

  The base unit 60 determines the posture of the measurement unit 50 with respect to the second member by contacting the second member. Since the measurement direction of the measurement unit 50 is stabilized, the measurement accuracy of the measurement unit 50 is good, and the parallelism measurement accuracy can be improved.

  The base part 60 may be in contact with the parallelism measurement surface of the second member at at least three points. The at least three points may not be on the same straight line but may be at the vertex of a polygon, for example. The backlash caused by slight distortion of the parallelism measurement surface of the second member is less than when the contact is surface contact, and the measurement direction of the measurement unit 50 is easily determined.

  The measurement direction of the measurement unit 50 is a direction perpendicular to the plane including the at least three points. The measuring unit 50 may measure a linear distance between the first member and the second member on the straight line L1 that is equidistant from the at least three points. The movable part 51 may move on the straight line L1. The straight line L1 is perpendicular to the plane including the at least three points.

  The base portion 60 may include at least three balls 61 as contactors that make point contact with the second member. Although a cone may be used instead of the ball 61, damage due to contact can be suppressed as compared with the case where a cone is used.

  The base portion 60 may include a ball holder 62 that holds the at least three balls 61. The ball holder 62 may hold each ball 61 rotatably. Each ball 61 is rotatable about its center. Friction between each ball 61 and the second member can be reduced, and the measurement position can be easily changed.

  The position adjustment unit 70 adjusts the position of the measurement unit 50 with respect to the base unit 60 in the measurement direction of the measurement unit 50. The measurement range of the measurement unit 50 can be expanded.

  The position adjustment unit 70 connects the base unit 60 and the measurement unit 50 and is extendable in the measurement direction of the measurement unit 50. For example, the position adjustment unit 70 includes a first rod 71, a second rod 72, a third rod 73, a first intermediate plate 74, and a second intermediate plate 75.

  The first rod 71 connects the measurement unit 50 and the first intermediate plate 74. The second rod 72 connects the first intermediate plate 74 and the second intermediate plate 75. The third rod 73 connects the second intermediate plate 75 and the base portion 60. The first rod 71 and the third rod 73 may be disposed on the straight line L1, and the second rod 72 may be disposed in parallel with the straight line L1.

  One end of the second rod 72 may be inserted through the through hole of the second intermediate plate 75. One end of the second rod 72 forms a male screw 76, and the male screw 76 is screwed with a female screw 77. The female screw 77 is rotatably held with respect to the second intermediate plate 75.

  By rotating the female screw 77, the position of the second rod 72 relative to the second intermediate plate 75 can be adjusted. Therefore, the distance between the second intermediate plate 75 and the first intermediate plate 74 can be adjusted, and the position of the measurement unit 50 with respect to the base unit 60 can be adjusted.

  The other end of the second rod 72 may be inserted through the through hole of the first intermediate plate 74. The other end of the second rod 72 forms a male screw 78, and the male screw 78 is screwed with the female screw 79. The female screw 79 is rotatably held with respect to the first intermediate plate 74.

  By rotating the female screw 79, the position of the second rod 72 with respect to the first intermediate plate 74 can be adjusted. Therefore, the distance between the second intermediate plate 75 and the first intermediate plate 74 can be adjusted, and the position of the measurement unit 50 with respect to the base unit 60 can be adjusted.

  In the present embodiment, the relative positions of both the first intermediate plate 74 and the second intermediate plate 75 and the second rod 72 are variable, but either the first intermediate plate 74 or the second intermediate plate 75 is used. The relative position between the one and the second rod 72 may be variable. Further, the relative position between the second intermediate plate 75 and the third rod 73 may be variable, and the interval between the second intermediate plate 75 and the base portion 60 may be variable. Further, the relative position between the first intermediate plate 74 and the first rod 71 may be variable, and the interval between the measurement unit 50 and the first intermediate plate 74 may be variable.

  Next, referring to FIG. 3 again, a parallelism measuring method using the parallelism measuring apparatus 40 having the above configuration will be described.

  The operator adjusts the position of the measurement unit 50 with respect to the base unit 60 by expanding and contracting the position adjustment unit 70. Next, the operator inserts the parallelism measuring device 40 between the first member and the second member.

  The base unit 60 determines the posture of the measuring unit 50 with respect to the second member by contacting the second member. Since the measurement direction of the measurement unit 50 is stabilized, the measurement accuracy of the measurement unit 50 is good, and the parallelism measurement accuracy can be improved.

  The base part 60 may be in contact with the parallelism measurement surface of the second member at at least three points. The at least three points may not be on the same straight line but may be at the vertex of a polygon, for example. The backlash caused by slight distortion of the parallelism measurement surface of the second member is less than when the contact is surface contact, and the measurement direction of the measurement unit 50 is easily determined.

  In a state where the base unit 60 is pressed against the second member, the measuring unit 50 measures the linear distance between the first member and the second member. The urging portion 54 urges the movable portion 51 toward the reference position and presses the movable portion 51 against the first member. The displacement amount from the reference position of the movable unit 51 is measured by the displacement sensor unit 53. The displacement amount of the movable part 51 represents a linear distance between the first member and the second member.

  Thereafter, the operator changes the measurement position. While pressing the base portion 60 against the second member, the measurement position may be changed while the movable portion 51 is pressed against the first member. When the urging portion 54 is elastically deformed, a change in the linear distance between the first member and the second member can be absorbed.

  By measuring the amount of displacement of the movable portion 51 by changing the measurement position, the variation in the linear distance between the first member and the second member can be measured, and the parallelism between the first member and the second member can be measured. It can be measured.

  Based on the measurement result of the parallelism, the operator adjusts the postures of the first member and the second member with respect to the frame 11 to improve the parallelism between the first member and the second member. A molded product with good quality can be obtained stably.

  As mentioned above, although embodiment of the parallelism measuring method of an injection molding machine, etc. was described, the present invention is not limited to the above-mentioned embodiment, and within the scope of the gist of the present invention described in the claims, Various modifications and improvements are possible.

  For example, the injection molding machine 10 of the above embodiment is a horizontal type with a horizontal mold opening / closing direction, but may be a vertical type with a vertical mold opening / closing direction.

DESCRIPTION OF SYMBOLS 10 Injection molding machine 12 Fixed platen 13 Movable platen 15 Rear platen 32 Fixed mold 33 Movable mold 40 Parallelism measuring apparatus 50 Measuring part 51 Movable part 52 Guide part 53 Displacement sensor part 54 Energizing part 60 Base part 61 Ball 62 Ball holder 70 Position adjustment unit

Claims (6)

A measuring device of an injection molding machine that measures a linear distance between a first member and a second member,
A measurement unit that contacts the first member and measures a linear distance between the first member and the second member;
A base portion that determines the posture of the measuring portion relative to the second member by contacting the second member ;
A measurement apparatus for an injection molding machine , comprising: a position adjustment unit that connects the base unit and the measurement unit and adjusts a position of the measurement unit with respect to the base unit in a measurement direction of the measurement unit. The position adjustment unit includes a first rod coupled to the measurement unit, a third rod coupled to the base unit, and a second rod coupling the first rod and the third rod. ,
  By adjusting the position of the first rod and / or the third rod and the second rod, the position of the measurement unit with respect to the base unit is adjusted,
  2. The measurement device for an injection molding machine according to claim 1, wherein the second rod is disposed to be shifted in parallel with respect to the first rod and the third rod. The base portion contacts the parallelism measurement surface of the second member at at least three points that are not collinear.
The measurement device for an injection molding machine according to claim 1, wherein the measurement unit measures the linear distance in a direction perpendicular to a plane including the at least three points . The measurement of the injection molding machine according to any one of claims 1 to 3, wherein the measurement unit includes a contact that contacts the first member and a contact holder that rotatably holds the contact. apparatus. A stationary platen to which a stationary mold is attached;
A movable platen to which a movable mold is attached;
An injection molding machine provided with the measuring apparatus of any one of Claims 1-4 . A method for measuring parallelism of an injection molding machine that measures the parallelism between the first member and the second member using the measuring device according to any one of claims 1 to 4 ,
The position adjustment unit adjusts the position of the measurement unit with respect to the base unit in the measurement direction of the measurement unit,
Determine the posture of the measurement unit relative to the second member at the base portion that contacts the second member,
The linear distance between the first member and the second member in the measurement portion in contact with said first member is measured,
A method for measuring parallelism of an injection molding machine , wherein variations in the linear distance measured at a plurality of measurement positions are measured as the parallelism.

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