Mold exchange device for injection molding machine

Abstract

To provide an inexpensive mold exchange device for an injection molding machine.SOLUTION: A mold exchange device for an injection molding machine of the present invention includes: an injection molding machine; a mold exchange carriage movably provided next to the injection molding machine; and a carriage control system that controls a stop position of the mold exchange carriage. In the mold exchange device for the injection molding machine, the mold exchange carriage is moved by an induction motor, and the carriage control system has a positioning block whose movement stopping is controlled by a servo motor, and a positioning cylinder that abuts against the positioning block to stop the movement of the mold exchange carriage.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a mold changing device for an injection molding machine.

Background Art

[0002] As a mold changing device for an injection molding machine, the one described in Japanese Patent No. 5090812 (Patent Document 1) is known. This mold changing device controls the position of a self-propelled mold changing carriage by communicating between the control device of a two-mold-mounted injection molding machine and the control device of the self-propelled mold changing carriage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The mold placed on the self-propelled mold changing carriage of the prior art is heavy, and the self-weight of the mold changing carriage for transporting the mold is also large. Therefore, the carriage with a large inertia decelerates as it approaches the side of the injection molding machine and is controlled by a carriage control system to reduce the impact at the time of stopping and ensure the stopping position accuracy.

[0005] The positioning control of the self-propelled mold changing carriage by this carriage control system is performed by a servo motor, and the device is very expensive.

[0006] Therefore, an object of the present invention is to provide a mold changing device that can control the position of a mold changing carriage at low cost.

Means for Solving the Problems

[0007] To achieve the above object, the present invention takes the following means. That is, in an injection molding machine mold changing device having an injection molding machine, a mold changing carriage movably provided laterally of the injection molding machine, and a carriage control system for controlling the stop position of the mold changing carriage, the movement of the mold changing carriage is performed by an induction motor, and the carriage control system includes a positioning block whose movement stop is controlled by a servo motor, and a positioning cylinder that abuts against the positioning block to stop the movement of the mold changing carriage.

Advantages of the Invention

[0008] According to the present invention, since the heavy mold changing carriage is driven by an induction motor and the position control of the positioning block is performed by a servo motor, the carriage control system can be miniaturized, and thus it becomes less expensive than the conventional one.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

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Figure 9

Modes for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. What is shown in FIGS. 1 to 6 is a first embodiment of the present invention.

[0011] The mold exchange device of the injection molding machine includes an injection molding machine 1, a mold exchange carriage 2 movably provided beside the injection molding machine 1, and a carriage control system 3 for controlling the stop position of the mold exchange carriage 2.

[0012] The movement of the mold exchange carriage 2 is performed by an induction motor (not shown).

[0013] The carriage control system 3 includes a positioning block 5 whose movement stop is controlled by a servo motor 4, and a positioning cylinder 6 that abuts against the positioning block 5 to stop the movement of the mold exchange carriage 2.

[0014] The injection molding machine 1 is a two-mold-mounted injection molding machine. Since this two-mold-mounted injection molding machine 1 is substantially the same as that described in Patent Document 1, its detailed configuration will be omitted and will be briefly described below.

[0015] The two-mold-mounted injection molding machine 1 (hereinafter simply referred to as "injection molding machine") has a fixed platen 7, a movable platen 8, and a rotating platen 9 between the two. A mold 11a is attached to the fixed platen 7 and the rotating platen 9, and a mold 11b is attached to the rotating platen 9 and the movable platen 8. In FIG. 1, the molds 11a and 11b are removed and placed on the mold exchange carriage 2 as used molds, and the updated molds 11a and 11b to be carried in are placed on the mold exchange carriage 2.

[0016] The mold exchange carriage 2 is arranged beside the injection molding machine 1. Two guide rails 12 are laid beside the injection molding machine 1. The mold exchange carriage 2 has wheels 13 that run on the guide rails 12. These wheels 13 have drive wheels driven by an induction motor (not shown). On the upper surface of the mold exchange carriage 2, four sets of mold platforms equipped with rollers 14 for carrying the mold in and out between the injection molding machine 1 are provided. The mold exchange carriage 2 is composed of a loading platform 2a for unloading and a loading platform 2b for loading, on which the used molds 10a, b unloaded from the injection molding machine 1 and the updated molds 11a, b to be loaded are placed.

[0017] An LM guide 15 (registered trademark of THK) is provided between the two guide rails 12 in parallel with the guide rails 12 (see FIGS. 4 and 5). A positioning block 5 is movably provided on the LM guide 15. A nut 16a is provided on the positioning block 5, and a ball screw 16 is screwed into this nut 16a. The ball screw 16 is rotationally driven by the servo motor 4. The end of the ball screw 16 and the output shaft of the servo motor 4 are interlocked by a chain 17 or a belt.

[0018] As shown in FIG. 5, a positioning cylinder 6 that abuts against the positioning block 5 to stop the movement of the mold exchange carriage 2 is provided on the mold exchange carriage 2. The positioning cylinder 6 has a stopper pin 18 that can advance and retreat in the vertical direction. In a state where the stopper pin 18 protrudes downward, it abuts against the side surface of the positioning block 5 to stop the movement of the mold exchange carriage 2 and perform positioning. In a state where it moves upward, the stopper pin 18 does not abut against the positioning block 6, so the movement of the mold exchange carriage 2 is allowed.

[0019] Note that the positioning cylinder 6 is provided at two locations, namely, the unloading platform 2a and the loading platform 2b for loading.

[0020] A sensor (not shown) for detecting the positioning block is provided near the positioning cylinder 6. The induction motor is controlled so that the movement of the mold change carriage 2 decelerates and stops upon detection by this sensor.

[0021] An intermediate carriage 19 for loading and unloading molds is provided between the injection molding machine 1 and the mold change carriage 2. The intermediate carriage 19 has wheels 21 that run on a rail 20 so that it can move parallel to the mold change carriage 2. The movement stop of the intermediate carriage 19 is controlled by a servo motor 4 for driving the positioning block (see Fig. 6). A nut 22 is provided on the intermediate carriage 19, and a ball screw 23 is screwed into this nut 22. The ball screw 23 is rotationally driven by the servo motor 4.

[0022] Next, the operation of the carriage control system 3 during mold change will be described. During mold change, the mold change carriage 2 loads the update molds 11a and b onto the loading platform 2a for loading, and the unloading platform 2b is an empty platform, prepared as a space for accommodating the used mold. The mold change carriage 2 is moved by driving the induction motor so that the unloading platform 2a is positioned at a predetermined position on the side of the injection molding machine 1. At this time, when the sensor detects the positioning block 5, it is controlled to decelerate and stop.

[0023] As shown in Fig. 5, the mold change carriage 2 stops at an accurate position when the stopper pin 18 of the positioning cylinder 6 of the mold change carriage 2 abuts against the positioning block 5.

[0024] The positioning control of the positioning block 5 is performed by controlling the servo motor 4 based on the platen position data of the injection molding machine 1 so that the mold change carriage 2 stops at an appropriate position.

[0025] After the unloading platform 2a of the mold change carriage 2 stops at an accurate position, the used molds 10a and b removed from the injection molding machine 1 are unloaded onto the empty unloading platform 2a. This state is the state shown in Fig. 1.

[0026] Thereafter, in order to carry the renewal molds 11a and 11b into the injection molding machine 1, the mold exchange carriage 2 is moved by the drive of the induction motor.

[0027] Prior to this, the position of the positioning block 5 is changed to the position for the renewal molds 11a and 11b. This position change is changed by controlling the servo motor 4 according to the platen position data of the injection molding machine 1 so that it becomes the proper stop position of the mold exchange carriage 2.

[0028] After the position of the positioning block 5 is changed, the mold exchange carriage 2 is moved by the drive of the induction motor so that the loading platform 2b for loading is located at a predetermined position on the side surface of the injection molding machine 1. When the sensor detects the positioning block 5, it is decelerated and stopped.

[0029] The mold exchange carriage 2 stops at the exact position by the stopper pin 18 of the positioning cylinder 6 of the mold exchange carriage 2 abutting against the positioning block 5. This state is shown in Fig. 2.

[0030] After the mold exchange carriage 2 stops at the exact position, the renewal molds 11a and 11b are carried into the injection molding machine 1.

[0031] Thereafter, the stopper pin 18 of the positioning cylinder 6 is moved upward to release the contact with the positioning block 5, and the induction motor is driven to move the mold exchange carriage 2 to the mold preparation warehouse.

[0032] In addition, when controlling the position of the positioning block 5, the position of the intermediate carriage 19 is also simultaneously performed by the servo motor 4.

[0033] Conventionally, the intermediate carriage was fixedly provided on the side of the injection molding machine, but in this embodiment, it will be arranged at a more accurate position when changing the mold.

[0034] According to the above embodiment, the position control of the positioning block 5 can be achieved with a small servo motor 4, which can be made into a less expensive device compared to the large servo motors that drive the conventional large-weight mold-exchanging carriage.

[0035] What is shown in FIGS. 7 to 9 is the second embodiment of the present invention. The difference from the first embodiment is that the positioning block 5 is connected to the intermediate carriage 19.

[0036] In the second embodiment, the LM guide 15 is arranged between the mold-exchanging carriage 2 and the intermediate carriage 19. The positioning block 5 is provided on this LM guide 15, and the control of the position of the positioning block 5 is performed by the servo motor 4, which is the same as in the first embodiment.

[0037] The positioning block 5 and the intermediate carriage 19 are connected via a connecting plate. The positioning cylinders 6 are provided at two locations on the side surface of the mold-exchanging carriage 2.

[0038] The functions and effects of the second embodiment are the same as those of the first embodiment.

[0039] The present invention is not limited to what is shown in the above embodiments. For example, the injection molding machine is not limited to the two-mold mounting type, and may be a two-material injection molding machine, a molding machine for a stack mold, etc. The intermediate carriage is not limited to being movable. Also, the concave-convex relationship of the contact between the positioning block and the positioning cylinder may be reversed. The arrangement relationship between the loading platform for unloading and the loading platform for loading may also be reversed.

[0040] The scope of the present invention is defined not by the above description, but by the claims, and includes all modifications within the meaning and scope equivalent to the claims.

Explanation of Reference Numerals

[0041] 1 Injection molding machine 2 Mold-exchanging carriage 2a Loading platform for unloading 2b Loading platform for loading 3. Bogie control system 4 servo motors 5 Positioning Block 6 Positioning cylinder 7 Fixed type board 8 Movable mold board 9 Rotating platen 10a, b Used mold 11a,b Mold for renewal 12 Guide rail 13 wheels 14 Laura 15 LM guide 16 ball screw 16a nut 17 Chain 18 Stopper pin 19 Intermediate bogie 20 Rails (for intermediate carriages) 21 Wheels (for intermediate trucks) 22 Nut (for intermediate truck) 23 Ball screw (for intermediate carriage) 24 Blocks (connected with intermediate bogies)

Claims

【Claim 1】 In an injection molding machine mold changing device having an injection molding machine, a mold changing carriage movably provided laterally of the injection molding machine, and a carriage control system for controlling a stop position of the mold changing carriage, the movement of the mold changing carriage is performed by an induction motor, the carriage control system has a positioning block whose movement stop is controlled by a servo motor, and a positioning cylinder that abuts against the positioning block to stop the movement of the mold changing carriage, in an injection molding machine mold changing device.

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