CN114007834A

CN114007834A - Manufacturing method and injection molding system

Info

Publication number: CN114007834A
Application number: CN202080045685.5A
Authority: CN
Inventors: 小平弘毅; 柳原裕一
Original assignee: Canon Virginia Inc
Current assignee: Canon Virginia Inc
Priority date: 2019-05-17
Filing date: 2020-05-13
Publication date: 2022-02-01
Anticipated expiration: 2040-05-13
Also published as: JP7313483B2; CN116872430A; WO2020236495A1; CN114007834B; JP2022538728A

Abstract

A method for manufacturing a molded part while changing between a plurality of molds, comprising: a first ejection step of opening the first mold and ejecting the molded part from the first mold; an inspection step of inspecting the ejected molded part to determine whether the molded part is acceptable; a first injection step of closing the first mold and performing injection into the first mold; a second ejection step of, in a case where it is determined that the ejected molded part is acceptable, replacing the first mold with a second mold and ejecting the molded part from the second mold after the first injection step; and a third ejection step of, in a case where it is determined that the molded part ejected in the first ejection step is not acceptable, not replacing the first mold with the second mold and ejecting the molded part from the first mold.

Description

Manufacturing method and injection molding system

Cross Reference to Related Applications

This application claims the benefit of U.S. provisional application 62/849738 filed on 5, 17, 2019.

Technical Field

The present disclosure relates to an injection molding system.

Background

Manufacturing a molded part by an injection molding machine includes: injecting resin into the mold after clamping the mold; pressing the resin into the mold at high pressure to compensate for the volume reduction due to the curing of the resin; holding the molded part in the mold until the resin is cured; and ejecting the molded part from the mold.

Among the above molding methods, a method of using two molds together with one injection molding machine to improve productivity has been proposed. For example, it can be seen that US 2018/0009146/japanese patent publication No.2018-001738/VN20160002505 discusses a system in which the conveying

devices

3A and 3B are arranged on both sides of the injection molding machine 2. In this system, molded parts are manufactured while conveying

devices

3A and 3B replace a plurality of molds for one injection molding machine 2. Fig. 1 to 2 show an injection molding system of US 2018/0009146/japanese patent publication No.2018-001738/VN 20160002505.

In this system, cooling of the mold 100A or 100B is performed on the

conveyor

3A or 3B outside the injection molding machine 2. During cooling of one of the molds 100A/100B, each molding part ejection → clamping → injection/pressure holding process is performed on the other mold 100A/100B by the injection molding machine 2. Since the opening and the molded part ejection are performed by the injection molding machine 2, the

conveyors

3A, 3B do not need a function for the opening and a function for the ejection of the molded part.

This enables the molded part P to be manufactured by one injection molding machine 2 while replacing a plurality of molds. This may reduce the overall cost of the system.

If the time required from the start of the mold replacement process to the other mold ejection process, the injection process, and the pressure holding process, and all the processes until the mold replacement process is completed again, is adapted to the time required for cooling one of the molds, the productivity is improved by a maximum of two times as compared with the ordinary molding. That is, there is an advantage that high productivity can be achieved in addition to suppressing an increase in cost.

Techniques for heating and cooling forming are known. In this technique, a mold is heated in advance to a temperature higher than the heat distortion temperature of the resin, and after the resin is injected into the mold, the mold is cooled. Although this technique can prevent appearance defects of the molded part, it requires equipment for forced heating and cooling. Furthermore, there is a disadvantage that the molding process is longer than the typical molding method.

A method for inspecting/inspecting a molded part is disclosed in japanese patent laid-open No.2007 & 304011. In this case, the molding nut is placed on the rotary table, the capturing unit captures an image of the molding nut, and the quality of the molding nut is determined by analyzing the captured image.

There is a need for a technique of performing injection molding while replacing a plurality of molds and inspecting the molded parts.

Disclosure of Invention

According to at least one aspect of the present disclosure, a method for manufacturing a molded part by an injection molding machine while exchanging between a plurality of molds, the method includes: a first ejection step of opening a first mold in the injection molding machine and ejecting the molded part from the first mold; an inspection step of inspecting the molded part ejected in the first ejection step to determine whether the molded part is an acceptable part; a first injection step of closing the first mold and performing injection into the first mold; a second ejection step of, in a case where it is determined that the molded part ejected in the first ejection step is an acceptable part, replacing a first mold in an injection molding machine with a second mold and ejecting the molded part from the second mold after the first injection step; and a third ejection step of, in a case where it is determined that the molded component ejected in the first ejection step is an unacceptable component, not replacing the first mold with the second mold and ejecting the molded component from the first mold.

This and other embodiments, features, and advantages of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure, when read in conjunction with the accompanying drawings and the provided claims.

Drawings

Fig. 1 shows an injection molding system.

Fig. 2 shows a side view of the injection molding machine.

FIG. 3 illustrates a process of operation of the injection molding system.

FIG. 4 illustrates a process of operation of the injection molding system.

Fig. 5 illustrates the operation of the injection molding system.

Figure 6 shows the basic molding process.

Fig. 7 shows a chuck plate.

Fig. 8 shows a chuck plate.

Fig. 9 shows an injection molding process.

Throughout the drawings, the same reference numerals and characters, unless otherwise specified, are used to denote like features, elements, components or portions of the illustrated embodiments. Further, while the present disclosure will now be described in detail with reference to the figures, this is done in connection with the illustrative exemplary embodiments. It is intended that changes and modifications may be made to the described exemplary embodiments without departing from the true scope and spirit of the present disclosure as defined by the following claims.

Detailed Description

The present disclosure has several embodiments and relies on patents, patent applications, and other references to obtain details known to those skilled in the art. Thus, when a patent, patent application, or other reference is cited or repeated herein, it is understood that it will be incorporated by reference in its entirety for all purposes and for the subject matter recited.

Referring to the drawings, arrow symbols X and Y in each figure indicate horizontal directions orthogonal to each other, and arrow symbol Z indicates a vertical (standing) direction with respect to the ground.

Fig. 1-2 show an injection molding system 1 of US 2018/0009146/japanese patent publication No.2018-001738/VN20160002505 and are provided herein for information/descriptive purposes only.

The injection molding system 1 includes an injection molding machine 2,

conveyors

3A and 3B, and a control apparatus 4. The injection molding system 1 manufactures molded parts while replacing a plurality of molds for one injection molding machine 2 using the

conveyors

3A and 3B. Two molds 100A and 100B are used.

The molds 100A/100B are a pair of a fixed mold 101 and a movable mold 102 that opens/closes with respect to the fixed mold 101. The molded part is molded by injecting a molten resin into a cavity formed between the fixed mold 101 and the movable mold 102. The

clamping plates

101a and 102a are fixed to the fixed mold 101 and the movable mold 102, respectively. The

clamping plates

101a and 102a are used to lock the mold 100A/100B to the molding operation position 11 (mold clamping position) of the injection molding machine.

For the mold 100A/100B, a self-closing unit 103 is provided to maintain a closed state between the fixed mold 101 and the movable mold 102. The self-closing unit 103 makes it possible to prevent the mold 100A/100B from opening after the mold 100A/100B is unloaded from the injection molding machine 2. The self-closing unit 103 maintains the mold 100A/100B in a closed state using magnetic force. The self-closing units 103 are located at a plurality of positions along the opposing surfaces of the fixed mold 101 and the movable mold 102. The self-closing unit 103 is a combination of an element on the side of the fixed mold 101 and an element on the side of the movable mold 102. With respect to the self-closing unit 103, two or more pairs of self-closing units are generally installed for one of the molds 100A and 100B.

The conveyor 3A loads and unloads the mold 100A onto and from the molding operation position 11 of the injection molding machine 2. The conveyor 3B loads and unloads the mold 100B onto and from the molding operation position 11. The conveyor 3A, the injection molding machine 2, and the conveyor 3B are arranged in a line in this order in the X-axis direction. In other words, the conveyor 3A and the conveyor 3B are arranged laterally with respect to the injection molding machine 2 to sandwich the injection molding machine 2 in the X-axis direction. The

conveyors

3A and 3B are arranged to face each other, and the conveyor 3A is arranged on one side in the lateral direction of the injection molding machine 2, and the conveyor 3B is arranged on the adjacent other side, respectively. The forming operation position 11 is located between the conveyor 3A and the conveyor 3B. The

conveyors

3A and 3B respectively include a frame 30, a conveying unit 31, a plurality of rollers 32, and a plurality of rollers 33.

The frame 30 is a skeleton of the

conveyors

3A and 3B, and supports a conveying unit 31 and a plurality of

rollers

32 and 33. The conveying unit 31 is an apparatus that moves the mold 100A/100B back and forth in the X-axis direction and removes and inserts the mold 100A/100B with respect to the molding operation position 11.

The conveying unit 31 is an electrically driven cylinder having a motor as a driving source, and includes a rod that moves forward and backward with respect to the electrically driven cylinder. The electric driving cylinder is fixed to the frame 30, and the fixed die 101 is fixed to the edge portion of the rod. For the transfer unit 31, both fluid actuators and electric actuators may be used, wherein the electric actuators may provide better positional or velocity control accuracy when transferring the mold 100A/100B. For example, the fluid actuator may be an oil hydraulic cylinder or a pneumatic cylinder. The electric actuator may be a rack and pinion mechanism having a motor as a drive source, a ball screw mechanism having a motor as a drive source, or the like, in addition to the electric drive cylinder.

The conveying unit 31 is independently arranged for each of the

conveyors

3A and 3B. However, a common support member that supports the molds 100A and 100B may be used, and a single common conveying unit 31 may be arranged for the support member. The case where the conveying unit 31 is arranged independently for each of the

conveyors

3A and 3B makes it possible to cope with the case where the moving stroke is different between the mold 100A and the mold 100B at the time of conveying. For example, there is a case where the molds cannot be simultaneously conveyed due to a difference in width of the molds (width in the X direction) or a difference in thickness of the molds (width in the Y direction).

The plurality of rollers 32 are configured such that one row of rollers is arranged in the X-axis direction, wherein two rows are separately configured in the Y-axis direction. The plurality of rollers 32 rotate about the revolution axis in the Z-axis direction, and contact the side surfaces of the mold 100A/100B (the side surfaces of the

clamping plates

101a and 102 a) and support the mold 100A/100B from the sides to guide the movement of the mold 100A/100B in the X-axis direction. The plurality of rollers 33 are configured such that one row of rollers is arranged in the X-axis direction, wherein two rows are separately configured in the Y-axis direction. The plurality of rollers 33 rotate about the revolving axis in the Y direction, and support the bottom surface of the mold 100A/100B (the bottom surfaces of the

clamping plates

101a and 102 a) and the mold 100A/100B from below to smooth the movement of the mold 100A/100B in the X direction.

The control device 4 includes a controller 41 for controlling the injection molding machine 2, a controller 42A for controlling the conveyor 3A, and a controller 42B for controlling the conveyor 3B. Each of the

controllers

41, 42A, and 42B includes, for example, a processor such as a CPU, a RAM, a ROM, a storage device such as a hard disk, and an interface (not shown) connected to a sensor or an actuator. The processor executes programs stored in the storage device. An example of a program (control) executed by the controller 41 is described below. Controller 41 is communicatively connected to

controllers

42A and 42B and provides instructions to

controllers

42A and 42B related to the delivery of molds 100A/100B. If the loading and unloading of the mold 100A/100B is finished, the

controllers

42A and 42B transmit a signal of completion of the operation to the controller 41. Further, the

controllers

42A and 42B transmit an emergency stop signal to the controller 41 when an abnormal phenomenon occurs.

The controller is arranged for each of the injection molding machine 2, the conveyor 3A, the conveyor 3B, but one controller may control all three machines. The

conveyors

3A and 3B may be controlled by a single controller to achieve more reliable and coordinated operation.

The injection molding machine 2 comprises an injection device 5, a clamping device 6 and a take-out robot 7 for ejecting the molded parts. The injection device 5 and the clamping device 6 are arranged on the frame 10 in the Y-axis direction.

The injection device 5 includes an injection cylinder 51 arranged to extend in the Y-axis direction. The injection cylinder 51 includes a heating device (not shown) such as a band heater, and melts the resin introduced from the hopper 53. The screw 51a is integrated into the injection cylinder 51, and by the rotation of the screw 51a, plasticizing and metering of the resin introduced into the injection cylinder 51 are performed, and by moving the screw 51a in the axial direction (Y-axis direction), the molten resin can be injected from the injection nozzle 52.

In fig. 2, a shutoff nozzle is shown as an example of the nozzle 52. With the opening/closing mechanism 56 of fig. 2, a pin 56a for opening/closing the discharge port 52a is arranged. The pin 56a is connected to an actuator (cylinder) 56c via a link 56b, and by the operation of the actuator 56c, the discharge port 52a is opened and closed.

The injection cylinder 51 is supported by a drive unit 54. In the drive unit 54, a motor for plasticizing and measuring the resin by rotationally driving the screw 51a, and a motor for driving the screw 51a to move forward/backward in the axial direction are arranged. The drive unit 54 is movable forward/backward in the Y-axis direction along the rails 12 on the frame 10, and in the drive unit 54, an actuator (e.g., an electrically driven cylinder) 55 for causing the injection apparatus 5 to move forward/backward in the Y-axis direction is arranged.

The clamping device 6 performs clamping and opening and closing of the mold 100A/100B. In the clamping device 6, the following are sequentially arranged in the Y-axis direction: a fixed platen 61, a movable platen 62, and a movable platen 63. A plurality of tie rods 64 pass through the platens 61-63. Each of the tie bars 64 is a shaft extending in the Y-axis direction, one end of which is fixed to the fixed platen 61. Each of the tie bars 64 is inserted into a respective through hole formed in the movable platen 62. The other end of each of the tie bars 64 is fixed to the movable platen 63 by an adjusting mechanism 67. The

movable platens

62 and 63 are movable in the Y-axis direction along the rails 13 on the frame 10, and the fixed platen 61 is fixed to the frame 10.

The toggle mechanism 65 is disposed between the movable platen 62 and the movable platen 63. The toggle mechanism 65 moves the movable platen 62 forward/backward in the Y-axis direction with respect to the movable platen 63 (in other words, with respect to the fixed platen 61). The toggle mechanism 65 includes links 65a to 65 c. The link 65a is rotatably connected to the movable platen 62. The link 65b is pivotally connected to the movable platen 63. The link 65a and the link 65b are pivotably connected to each other. The link 65c and the link 65b are pivotably connected to each other. Link 65c is pivotally connected to arm 66 c.

The arm 66c is fixed to the ball nut 66 b. The ball nut 66b engages the ball screw shaft 66a extending in the Y-axis direction, and is moved forward/backward in the Y-axis direction by the rotation of the ball screw shaft 66 a. The ball screw shaft 66a is supported by the movable platen 63 so as to be freely rotatable, and the motor 66 is supported by the movable platen 63. The motor 66 rotationally drives the ball screw shaft 66a while detecting the amount of rotation of the motor 66. Driving the motor 66 while detecting the amount of rotation of the motor 66 enables clamping, opening, and closing of the mold 100A/100B to be performed.

The injection molding machine 2 includes sensors 68 for measuring the clamping force, wherein each sensor 68 is, for example, a strain gauge provided on the tie bars 64, and calculates the clamping force by detecting distortion of the tie bars 64.

The adjustment mechanism 67 includes: a nut 67b supported to rotate freely on the movable platen 63, a motor 67a as a driving source, and a transmission mechanism for transmitting the driving force of the motor 67a to the nut 67 b. Each of the tie rods 64 passes through a hole formed in the movable platen 63, and is engaged with a nut 67 b. By rotating the nut 67b, the engagement position between the nut 67b and the tie bar 64 in the Y-axis direction changes. That is, the position at which the movable platen 63 is fixed with respect to the tie bars 64 changes. Thereby, the space between the movable platen 63 and the fixed platen 61 can be changed, and thereby the clamping force and the like can be adjusted.

The molding operation position 11 is a region between the fixed platen 61 and the movable platen 62.

The mold 100A/100B introduced into the molding operation position 11 is sandwiched between the fixed platen 61 and the movable platen 62 and is thereby clamped. The opening and closing is performed by moving the movable platen 62 based on the movement of the movable mold 102.

The takeout robot 7 includes a rail 71 extending in the X-axis direction, and a movable rail 72 movable on the rail 71 in the X-axis direction. The movable rail 72 is arranged to extend in the Y-axis direction, and a slider 73 is arranged on the movable rail 72. The slider 73 is guided by the movable rail 72 to move in the Y-axis direction, and moves up and down along the elevating shaft 73a in the Z-axis direction. At the lower end of the elevating shaft 73a, a vacuum head 74 is disposed, and on the vacuum head 74, a chuck plate 75 dedicated to molding parts is mounted.

The take-out robot 7, after being opened, moves the vacuum head 74 between the fixed mold 101 and the movable mold 102 as shown by the broken lines in fig. 2 by the rail 71, the movable rail 7, and the slider 73, holds the molded part, and conveys the molded part to the outside of the mold 100A/100B.

The capture device 76 is located above the stationary platen 61. The capturing device 76 captures the molded part in a state where the vacuum head 74 holds the molded part to enable inspection of the molded part.

Fig. 3 shows a flowchart of the processing performed by the controller 41. When the flowchart begins to execute, one of the molds 100A and 100B cools on its respective conveyor while the other mold is in the process of holding pressure after injection in the injection molding machine 2.

In S1, the mold 100A/100B in the injection molding machine 2 and the mold 100A/100B on the conveyor 3A/3B are replaced (replaced).

The molds 100A/100B conveyed into the injection molding machine 2 in step 1 are cooled in advance outside the injection molding machine.

In S2, the mold 100A/100B in the injection molding machine 2 is opened.

In S3, the removal robot 7 removes (ejects) the molded component from the opened mold 100A/100B.

In S4, the capturing device 76 captures an image of the molded part held by the takeout robot 7, and inspects the molded part. In the case where the period of time for analyzing the captured image is an extended period, the process may be performed in parallel with the process of step 5.

In S5, a series of processes of clamping, injection into the mold 100A/100B, and pressure holding are performed.

In S6, it is determined whether the molded part is considered acceptable or unacceptable based on the result of inspecting the molded part. In the present embodiment, the molded component is inspected for the surface condition and the shape of the molded component based on the captured image. The molded part may be inspected for its color based on the captured image.

If it is determined that the molded part is acceptable, the process returns to S1 and the molds 100A and 100B are replaced.

If it is determined that the molded part is not acceptable, the molds 100A and 100B are not replaced, and the process proceeds to S7. In S7, the process waits until the molding material injected into the mold in S5 is sufficiently cooled. Once sufficiently cooled, the unacceptable component is discarded by moving it to a different location than the acceptable component. Then, the process proceeds to S1, where the molds 100A and 100B are replaced.

As described above, in the flowchart of fig. 3, if the molded part is acceptable, the molds 100A and 100B are replaced, and the process is repeated. If the molded part is unacceptable, the molds 100A and 100B are not replaced and the opening and ejection process is performed for the same mold 100A/100B. This enables rapid remanufacturing of molded parts when the ejected molded part is unacceptable. The process also enables the order of the ejected parts to be maintained as needed, such as when the molded part a and molded part B need to be loaded in the storage container alternately.

Fig. 4 shows a flowchart of the processing performed by the controller 41. S1 to S5 in fig. 4 are the same as S1 to S5 in fig. 3, and a description thereof will not be given here.

In S8, the molds 100A and 100B are replaced after the compaction process.

In S9, it is determined whether the molded part is considered acceptable or unacceptable based on the result of inspecting the molded part. If it is determined that the molded part is acceptable, return is made to S2.

If it is determined that the molded part is not acceptable, the flow proceeds to S10. In S10, the process waits until the molding material injected into the mold in S5 is sufficiently cooled. Once sufficiently cooled, the unacceptable component is discarded by moving the unacceptable component to a different location than the acceptable component. Then, the process proceeds to S1, where the molds 100A and 100B are replaced. This enables rapid remanufacturing of molded parts when the ejected molded part is unacceptable.

As described above, in the flowchart of fig. 4, the molds 100A and 100B are replaced before determining whether the molded part is acceptable, and it is determined whether the molded part is acceptable before opening the replaced mold 100A/100B. In the event that the molded part is acceptable, the wait time until determining whether the molded part is acceptable may be reduced or eliminated. In the case where the molded part is unacceptable, the molds 100A and 100B are replaced again, and the molds 100A/100B used in manufacturing the unacceptable part are returned to the injection molding machine 2. Because the rate at which acceptable molded parts are manufactured is greater than the likelihood that the molded parts are unacceptable, the time required to perform the entire process can be reduced.

In the flowchart of fig. 4, the checking process is performed in S4, and the determining process is performed in S9. In another exemplary embodiment, when the inspection process is started in S4, the inspection process and the determination process may be performed in parallel with the clamping, injection, holding pressure process in S5 and the replacement process in S8. In this case, the determination process in S9 may be performed between S5 and S8.

If the determination processing in D9 is completed before the completion of the process in S5 or immediately after the completion of the process in S5, the same process shown in fig. 3 is performed. That is, the replacement process in S8 is omitted, and the molds 100A, 100B are replaced in S1 in a case where it is determined in S9 that the molded part is acceptable, and the process in S10 and the process in S2 are performed in a case where it is determined in S9 that the molded part is not acceptable.

As described above, the present embodiment can switch between the process in fig. 3 and the process in fig. 4 based on the time of the acquisition and checking process. The process of fig. 4 provides an enhancement to the process of fig. 3, for example, in the case where the period of time for performing image processing and analysis on the captured image is long and the determination process is not completed after the hold-down process is completed.

Fig. 5 shows a flowchart of the processing performed by the controller 41. More specifically, the controller 41 manages the number of molded parts manufactured by both the mold 100A and the mold 100B, and updates the planned number of molded parts based on the manufacture of unacceptable parts.

At the start of execution of the flowchart, one of the molds 100A and 100B is cooled on its conveyor, while the other mold is in the process of holding pressure after injection in the injection molding machine 2.

In S51, the controller 41 sets the number of molded parts manufactured by each of the mold 100A and the mold 100B. In an exemplary embodiment, the controller 41 performs the process in response to an input by a user. The controller 41 assigns a plan number "n" to a variable Na indicating the remaining number of molded parts manufactured by the mold 100A. The controller 41 assigns a plan number "m" to the variable Nb indicating the remaining number of molded parts manufactured by the mold 100B.

In S52, it is determined whether the remaining number Na is equal to 0. If Na is equal to 0, the process proceeds to S57. If Na is not equal to 0, the process proceeds to S53. In S53, the mold 100A is conveyed into the injection molding machine 2. If the mold 100A is already in the injection molding machine 2 at this time, the controller 41 does not perform any processing.

In S54, the basic molding process P shown in fig. 6 is performed with the mold 100A.

The basic molding process P is a standard process of transferring the mold into the injection molding machine 2.

In this embodiment, the basic molding process includes opening the mold, ejecting the molded part, capturing and inspecting the molded part, clamping, injecting, and holding pressure. However, the basic molding process may be replaced based on the molded parts and the molding process employed by the injection molding machine 2. During the inspection of the basic molding process P, the take-out robot 7 maintains holding the molded component. In another exemplary embodiment, a work bench and an inspection apparatus may be provided near the injection molding system 1, and an inspection process may be performed on the work bench.

In S55, it is determined whether the molded part ejected in S54 is acceptable. If the molded part is acceptable, the process proceeds to S56. In S56, the remaining amount Na of the mold 100A is decreased by 1.

If the molded part is not acceptable, the process proceeds to S57, and the remaining amount Na is not reduced. That is, the molded parts will be remanufactured to the same number of unacceptable parts.

In S57, it is determined whether the remaining number Nb is equal to 0. If Nb is equal to 0, the process proceeds to S62. If Na is not equal to 0, the process proceeds to S58. In S58, the mold 100B is conveyed into the injection molding machine 2. If the mold 100B is already in the injection molding machine 2 at this time, the controller 41 does not perform processing.

In S59, the basic molding process P shown in fig. 6 is performed using the mold 100B.

In S60, it is determined whether the molded part ejected in S59 is acceptable. If the molded part is acceptable, the process proceeds to S61. In S61, the remaining number Nb of the die 100B is reduced by 1.

If the molded part is not acceptable, the process proceeds to S62, and thus the remaining amount Nb is not reduced. That is, the molded parts will be remanufactured to the same number of unacceptable parts.

In S62, it is determined whether both the remaining number Na and the remaining number Nb are equal to 0. If Na and Nb are equal to 0, the process ends. If Na or Nb is not equal to 0, the process returns to S52.

The process of fig. 5 is repeated until Na and Nb are equal to 0.

As described above, in the present embodiment, the preset number of manufactured molded parts may be changed based on the result of the inspection apparatus in response to determining that the molded parts are unacceptable. The above-described embodiments also provide an efficient manufacturing method for performing injection molding while replacing a plurality of molds, the method including an inspection process in the manufacturing process.

In another exemplary embodiment, the inspection process for the molded part is included in injection molding in which assembly in a mold or insert molding is performed while replacing a plurality of molds. The following describes the configuration and process flow for assembly in a mold.

Fig. 7 is provided herein for the purpose of providing information only. EX1 of fig. 7 indicates one example of the chuck plate 75. The chuck plate 75 includes a holding portion 75A and a holding portion 75B. The vacuum head 74 causes the chuck plate 75 to rotate about the axis 74a, and causes the chuck plate 75 to displace, so that the positions of the holding portion 75A and the holding portion 75B change. This provides for switching the holding portion facing the molded component, handling different molded components in a short time, without the need to replace the chuck plate 75. EX2 of fig. 6 shows another example of the chuck plate 75. The chuck plate 75 includes a holding portion 75A and a holding portion 75B. The vacuum head 74 includes a guide rail 74b and a slider 74c that moves along the guide rail 74b, and a chuck plate 75 is disposed on the slider 74 c. Moving the slider 74c causes the chuck plate 75 to be displaced to change the positions of the holding portion 75A and the holding portion 75B. This provides for switching the holding portion facing the molded component, handling different molded components in a short time, without the need to replace the chuck plate 75.

Fig. 9 is a flowchart illustrating an example of a control method of the injection molding system 1 executed by the controller 41. In the following example, a case is conceived where the molding operation is performed while the molds 100A and 100B are replaced in the following manner: molding using the mold 100A → molding using the mold 100B → molding using the mold 100A, and the like. However, when the mold 100B is opened, the molded part a molded in the mold 100A is placed in the mold 100B. Then, a resin is injected in the mold 100B accommodating the molded part a, and the molded part B integrated with the molded part a is manufactured.

At the start of this process flow, the mold 100B into which the resin has been injected is unloaded from the injection molding machine 2 to the conveyor 3B. The following description describes the process after this step. In step S1 of fig. 5, the cooled mold 100A is loaded into the injection molding machine 2. The mold a includes a molded part a made of resin injected in the previous cycle and then hardened in a cooling process. In step S2, the motor 66 is driven to move the movable platen 62 away from the fixed platen 61. The fixed mold 101 is fixed to the fixed platen 61 by a fixing mechanism 610, and the movable mold 102 is fixed to the movable platen 62 by the fixing mechanism 610. Accordingly, the movable mold 102 is separated from the fixed mold 101, and the mold 100A is opened.

In step S3, the takeout robot 7 drives the holding portion 75A to remove the molded component a left on the side of the movable mold 102 of the mold 100A. The removed molded component a continues the process of being held by the holding portion 75A until step S12.

In step S4, the clamping device 6 drives the motor 66 to drive the toggle mechanism 65 to perform clamping of the mold 100A with the fixed platen 61 and the movable platen 62.

In step S5, preparation for injection into the mold 100A is performed by the injection machine 5. Injector 5 drives actuator 55 to move injector 5 to move nozzle 52 so that it contacts mold 100A.

In step S6, injection of the molten resin and pressure holding are performed. The injection machine 5 is driven to fill molten resin from the nozzle 52 into the cavity in the mold 100A and to press the resin into the mold 100A at high pressure so as to compensate for the volume reduction due to the solidification of the resin. During the process of step S6, the actual clamping force is measured by the sensor 68. During molding, since the temperature of the mold 100A gradually increases, the mold 100A thermally expands. There are cases where a difference is generated in the initial clamping force and the clamping force after a lapse of time. Therefore, the clamping force at the next clamping can be corrected based on the measurement result of the sensor 68.

The adjustment of the clamping force is performed by adjusting the position of the movable platen 63 relative to the tie bars 64 by driving the motor 67. The accuracy of the clamping force can be improved by adjusting the clamping force by correcting the initial value of the position of the movable platen 63 relative to the tie bars 64 based on the measurement results of the sensors 68. The adjustment of the position of the movable platen 63 with respect to the tie bars 64 may be performed at any time (e.g., steps S6, S7, S13 to S15 in the flowchart of fig. 5).

In step S7, processing related to the clamping device 6 is executed. First, the mold 100A is unlocked by the fixing mechanism 610. The motor 66 is driven to drive the toggle mechanism 65. This results in the clamping force being removed, the movable platen 62 slightly separating relative to the fixed platen 61, and creating a space for the interchangeable molds 100A and 100B.

In step S8, the mold 100A is unloaded or ejected from the molding operation position 11 to the conveyor 3A. After the mold 100A is ejected from the molding operation position 11, the mold 100A is cooled to a suitable temperature during a predetermined period of time. The mold typically includes a channel extending inside the mold, and a temperature controller is connected via a hose to an interface of the channel formed on the surface of the mold while the mold is ready for injection molding. The fluid at a certain temperature flows out from a temperature controller inside the mold to maintain the mold at a certain temperature. During the injection molding process, which includes a cooling process, the fluid generally always flows inside the mold.

Typically, after step S8, the mold 100A is still heated by the molten resin injected into the mold 100A. During cooling by the fluid from the temperature controller, the temperature drops to a predetermined temperature, for example 60 degrees celsius. The cooling process continues until a predetermined period of time has elapsed since the start of the cooling process.

In some injection molding processes, such as heating and cooling molding, the cooling process includes a dedicated temperature controller to cool the mold to a particular temperature that is different from the temperature at which the mold receives molten resin from the injection machine.

In step S9, the mold 100B is loaded from the conveyor 3B to the molding operation position 11. In step S10, the movable platen 62 is separated from the fixed platen 61 by driving the motor 66. The fixed mold 101 is fixed to the fixed platen 61 by a fixing mechanism 610, and the movable mold 102 is fixed to the movable platen 62 by the fixing mechanism 610. Accordingly, the movable mold 102 is separated from the fixed mold 101, and the mold 100B is opened against the force of the self-closing unit 103. In step S11, the molded component B, which is integral with the molded component a, left on the side of the movable mold 102 of the mold 100B is removed by driving the take-out robot 7 and using the holding portion 75B conveyed to the outside of the injection molding machine 2.

In step S12, the molded component a held by the holding portion 75A is placed in the metal mold B. In step S13, clamping of the mold 100B is performed. In step S14, preparation for injection into the mold 100B is performed by driving the actuator 55 to move the injection machine 5. This causes nozzle 52 to contact mold 100B.

In step S15, injection of the molten resin and pressure holding are performed. In step S16, the processing related to the chucking device 6 is executed, which is the same as the processing of step S7. In step S17, the mold 100B is unloaded from the molding operation position 11 to the conveyor 3B.

As described above, in the present embodiment, the cooling of the mold 100A/100B is performed on the

conveyor

3A or 3B outside the injection molding machine 2. Also, during cooling of one of the molds 100A or 100B, each process of molding part ejection → clamping → injection/pressure holding is performed on the other of the molds 100A or 100B by the injection molding machine 2. Since the opening and the molded part ejection are performed by the injection molding machine 2, the

conveyors

3A, 3B need not include a function for opening and a function for molded part ejection.

Therefore, the molded part B integrated with the molded part a can be manufactured by one injection molding machine 2 while replacing the plurality of molds 100A and 100B, while avoiding an increase in cost of the injection molding system 1. Since the injection molding system 2 molds the molded part B after the molding of the molded part a, it is not necessary to manufacture a large number of molded parts a in advance. Therefore, the risk of storing an excessive stock of molded parts a can be reduced.

Fig. 8 is an illustrative view of a chuck plate of another exemplary embodiment. Fig. 8 shows a chuck plate 74e connected to the end of the axis 74 d. The chuck plate 74e includes a plurality of holding portions 75A on one surface and a plurality of holding portions 75B on the other surface. The holding portion facing the molded component can be switched by rotating the chuck plate 74e about the axis 74 d. The rotation angle is not limited to 180 degrees. Any angle that enables the retaining portion to properly grasp and retain the molded part is suitable.

If it is necessary to cool the molded part sufficiently before placing it in the mold 100B, the molded part A may be cooled on the table during one or more cycles that have passed through the replacement of the molds 100A and 100B. In this case, the molded part a may be placed on a table for a period of time longer than the number of cycles required to cool the molded part. This enables the use of the molded part a molded before one or more replacement cycles as a molded part to be placed in the mold 100B.

The sensor may be mounted in the mold 100A/100B to enable detection of the molded part a being placed in the mold 100B. The sensors may be placed in the mold 100B or may be attached at different locations in the injection molding machine 2. A pressure sensor or an optical sensor may be used as the sensor.

An image of the placement condition may be obtained with a camera mounted near the molding operation position 11, where placement may be determined based on the obtained image.

A table may be prepared to adjust the holding direction of the molded component a held by the takeout robot 7. The repositioning of the profiled section a can also be carried out on a table. In this case, a configuration may be created in which a sensor mounted near the work table or on the take-out robot 7 is associated to change the hold to a certain orientation such that the molded part is placed in the mold 100B.

In the case where the molded part a is unacceptable, the molded part B including the molded part a does not become acceptable. Therefore, it should be performed to check (verify) whether the molded part a is acceptable before placing the molded part a in the mold 100B.

In the inspection process (inspection process), for example, a camera located in the injection molding machine 2 captures an appearance image of the molded part. The molded part is inspected for surface conditions and shapes of the molded part based on the captured image. The molded part may be inspected for its color based on the captured image. A capture device that uses radiation (such as X-rays) to capture the internal structure of the molded part may be used during the inspection process. In the case where the inspection step for the molded part B is performed outside the injection molding machine 2, the inspection step for the molded part a performed in the injection molding machine 2 may be only appearance inspection.

In the inspection process, the molded part a is removed by the take-out robot 7, one or more cameras capture an appearance image in a state where the molded part a is held by the take-out robot 7, analyze the captured image, and output a result indicating whether the molded part a is acceptable. The captured image may be analyzed by dedicated hardware.

The molded part a removed by the take-out robot 7 may be placed at a predetermined position outside the injection molding machine 2, and an inspection process for the molded part a may be performed outside the injection molding machine 2. In this case, the take-out robot 7 does not hold the molded part a during a period from when the take-out robot 7 removes the molded part a from the mold 100A to when the take-out robot 7 places the molded part a in the mold 100B.

After determining that the molded part is unacceptable, there are several options. In the first option, the mold 100A is not removed from the molding operation position 11 in the injection molding machine 2, and injection molding using the mold 100A is performed anew. In a case where the mold 100A has been previously removed from the injection molding machine 2 before the inspection process is performed, the mold 100A is moved to the injection molding machine 2 again, and the injection molding using the mold 100A is performed again. After this, the molded part a is re-inspected. If it is determined that the molded part A is acceptable, the molded part A is placed in the mold 100B. If it is determined that the molded part A is acceptable, the mold 100A is removed from the injection molding machine 2 and the mold 100B is moved into the injection molding machine 2.

In the second option, another acceptable part is prepared in advance outside the injection molding machine 2, and the prepared molded part a is held by the take-out robot 7 and used in place of the unacceptable part. In this case, based on the determination indicating that the molded part a is unacceptable, the control device 4 controls the takeout robot 7 so that the unacceptable part is removed from the takeout robot 7 and the unacceptable part is discarded. The prepared molded part a is held by the take-out robot 7 and placed in the mold 100B. If it is determined that the molded part a is acceptable, the molded part a just removed from the mold 100A by the take-out robot 7 is placed in the mold 100B.

In the third option, the take-out robot 7 places the molded part a at a predetermined position outside the injection molding machine 2. In this case, after placing the molded part a at the predetermined position, the take-out robot 7 holds another molded part a determined to be acceptable and places it in the mold 100B. This flow is effective in the case where the time required to inspect the molded component a is relatively long.

In a second option, it is preferable to produce some of the molded parts a beforehand. That is, the mold 100A is placed at the molding operation position 11, and injection molding is performed until a predetermined number (for example, 10) of acceptable molded parts a are produced. The injection molding machine 2 operates in a mode of performing injection molding using only the mold 100A. In the case where a predetermined number of acceptable molded parts a are produced, the injection molding machine 2 enters a mode in which the mold 100A and the mold 100B are alternately used for injection molding. A mode of performing injection molding using only the mold 100A can be realized in the third option.

In the injection molding process after it is determined in the first option that the molded part a is defective and the injection molding process for producing a predetermined number of molded parts a in advance, it is not necessary to cool the mold 100A at a position other than the molding operation position 11. In other words, it is not necessary to cool the mold 100A in a state where the mold 100A is removed from the injection molding machine 2. However, there is a difference between the pressure applied to the mold 100A/100B in the case where the mold is cooled on the conveyor 3A/3B and the pressure applied to the mold 100A/100B in the case where the mold 100A/100B is cooled at the molding operation position 11 in the injection molding machine 2, and therefore the quality of the mold 100A/100B may be different in each case.

In the above injection molding process, the mold 100A may be cooled in a state where the mold 100A is moved out of the molding operation position 11. The mold 100A may be cooled in a state where the mold 100A is at the molding operation position 11, and the fixed platen 61 and the movable platen 62 may be separated from the mold 100A. This makes the pressure applied to the mold 100A similar to the pressure in the state where the mold 100A is cooled on the conveyor 3A.

In the above-described embodiment, the clamping, injection/pressure holding, opening, and ejection are performed in the state where the mold 100A/100B is in the molding operation position 11, but this is not to be considered as limiting. It is not necessary to perform all the processes at the forming operation position 11. Part of the process may be performed at a different location than the forming operation location 11.

In the above-described embodiment, the cooling process is performed in a state where the mold 100A/100B is on the conveyor 3A/3B, but this is not to be construed as limiting. It is not necessary to perform the cooling process on the

conveyors

3A and 3B. The cooling process may be performed at a position where the mold 100A/100B does not contact the fixed platen 61 and the movable platen 62. For example, the cooling process may be performed in a state where a portion of the mold 100A/100B is in the injection molding machine 2 and another portion of the mold is outside the injection molding machine 2. In the case of a configuration in which a part of either of the

conveyors

3A and 3B is located in the injection molding machine 2, the cooling process may be performed in a state in which a part of the mold 100A/100B is in the injection molding machine 2 and another part of the mold 100A/100B is on either of the conveyors 3A/3B.

Definition of

In addressing the description, specific details are set forth in order to provide a thorough understanding of the disclosed examples. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present disclosure.

It will be understood that if an element or component is referred to herein as being "on," "against," "connected to," or "coupled to" another element or component, it can be directly on, against, connected to, or coupled to the other element or component, or intervening elements or components may be present. In contrast, if an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or component, there are no intervening elements or components present. When used, the term "and/or" includes any and all combinations of one or more of the associated listed items, if so provided.

For ease of description, spatially relative terms such as "under … … (under)", "under … … (beneath)", "under … … (below)", "under", "over … … (above)", "upper", "proximal", "distal", and the like may be used herein to facilitate describing the relationship of one element or feature to another or multiple elements or features as shown in the various figures. It will be understood, however, that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, spatially relative terms such as "under … …" may encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Similarly, the spatially relative terms "proximal" and "distal" may also be interchangeable as applicable.

The term "about" as used herein means, for example, within 10%, within 5%, or less. In some embodiments, the term "about" can mean within measurement error.

The terms first, second, third, etc. may be used herein to describe various elements, components, regions, sections and/or regions. It will be understood that these elements, components, regions, sections and/or regions should not be limited by these terms. These terms are only used to distinguish one element, component, region, section or section from another region, region or section. Thus, a first element, component, region, section or section discussed below could be termed a second element, component, region, section or section without departing from the teachings herein.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The use of the terms "a" and "an" and "the" and similar referents in the context of describing the disclosure (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. In particular, these terms, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof not expressly stated. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. For example, if the range 10-15 is disclosed, then 11, 12, 13, and 14 are also disclosed. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.

It will be appreciated that the methods and compositions of the present disclosure may be incorporated in the form of a variety of embodiments, only a few of which are disclosed herein. Variations of those embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the disclosure to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

Combinations of any of the exemplary embodiments disclosed above are also included as embodiments of the present disclosure. While the above exemplary embodiments discuss illustrative embodiments, these embodiments are not to be considered as limiting.

Claims

1. A method for manufacturing a molded part by an injection molding machine while changing between a plurality of molds, the method comprising:

a first ejection step of opening a first mold in the injection molding machine and ejecting the molded part from the first mold;

an inspection step of inspecting the molded part ejected in the first ejection step to determine whether the molded part is an acceptable part;

a first injection step of closing the first mold and performing injection into the first mold;

a second ejection step of, in a case where it is determined that the molded part ejected in the first ejection step is an acceptable part, replacing the first mold in the injection molding machine with a second mold and ejecting the molded part from the second mold after the first injection step; and

a third ejection step of, in a case where it is determined that the molded component ejected in the first ejection step is an unacceptable component, not replacing the first mold with the second mold and ejecting the molded component from the first mold.

2. The method of claim 1, wherein the shape of the first mold is different from the shape of the second mold.

3. The method of claim 1, wherein the inspecting step comprises analyzing a captured image of the molded part.

4. The method of claim 1, wherein the inspecting step is completed before initiating a change from the first mold to the second mold.

5. The method of claim 1, further comprising:

a placing step of placing the molded part ejected from the first mold into a cavity in the second mold; and

a second injection step of closing the second mold in which the molding member is placed and performing injection into the second mold.

6. The method of claim 5, wherein the placing step includes placing a molded part ejected from the first mold, inspected as an acceptable part, that is different from the unacceptable part, in a cavity in the second mold in the event that the molded part ejected from the first mold is an unacceptable part.

7. A method for manufacturing a molded part by an injection molding machine while alternating between a plurality of molds, the method comprising:

a first replacement step of replacing the first mold in the injection molding machine with a second mold;

a second ejection step of ejecting the molded part from the second mold after the first replacement step in a case where the molded part ejected in the first ejection step is an acceptable part; and

a second replacement step of, in a case where the molded part ejected in the first ejection step is an unacceptable part, not ejecting the molded part from the second mold and replacing the second mold in the injection molding machine with the first mold.

8. The method of claim 7, wherein the shape of the first mold is different from the shape of the second mold.

9. The method of claim 7, wherein the inspecting step comprises analyzing a captured image of the molded part.

10. The method of claim 7, wherein the inspecting step is completed before initiating a change from the first mold to the second mold.

11. The method of claim 7, further comprising:

12. The method of claim 11, wherein the placing step includes placing a molded part ejected from the first mold, inspected as an acceptable part, that is different from the unacceptable part, in a cavity in the second mold in the event that the molded part ejected from the first mold is an unacceptable part.

13. A method for manufacturing a molded part by an injection molding machine while alternating between a plurality of molds, the method comprising:

a setting step of setting, for each of the plurality of molds, the number of molded parts to be manufactured;

an ejection step of opening a mold and ejecting the molded part from the mold;

an inspection step of inspecting the molded part ejected in the ejection step to determine whether the molded part is an acceptable part; and

an updating step of updating the number of molded parts manufactured based on the number of molded parts determined as unacceptable parts based on a result of the checking step.

14. The method of claim 13, wherein the shape of each of the plurality of molds is different from one another.

15. The method of claim 13, wherein the updating step updates the number of molded parts manufactured for each of the plurality of molds.

16. An injection molding system comprising:

an injection molding machine;

a first conveyor located on a side of the injection molding machine and configured to convey a mold;

a second conveyor located on another side of the injection molding machine and configured to convey molds; and

a control unit for controlling the operation of the display unit,

wherein the improvement of the injection molding system comprises:

an inspection unit configured to inspect the molded part ejected from the mold to determine whether the molded part is an acceptable part, and

wherein the control unit updates a preset manufacturing number of the molded component based on a result made by the inspection unit.

17. The injection molding system of claim 16, wherein the inspection unit is an image capture unit.

18. The injection molding system of claim 16, further comprising a take-out unit configured to remove a molded part from the mold, wherein the inspection unit inspects the molded part held by the take-out unit.

19. The injection molding system of claim 16, further comprising a table on which molded parts ejected from the mold are placed, wherein the inspection unit inspects the molded parts placed on the table.

20. A method for manufacturing a molded part by an injection molding machine while changing between a plurality of molds, the method comprising:

a first injection step for injecting a material into a first mold positioned at a molding operation position of the injection molding machine;

a first ejection step for ejecting a molded part produced from the material injected in the first injection step from the first mold;

a second injection step for injecting a material into the first mold;

a determination step of determining whether the molded part ejected in the first ejection step is an unacceptable part;

a second ejection step for ejecting a molded part produced from the material injected in the second injection step from the first mold; and

a replacing step, performed after the determining step and before the second ejecting step, for transporting the first mold out of the molding operation position and transporting a second mold into the molding operation position, wherein the second mold is different from the first mold.