JP2652276B2 - Core exchange robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core changing robot used for exchanging a core of a mold in a molding machine using a mold such as an injection molding machine.

[0002]

2. Description of the Related Art In a molding machine using a mold such as an injection molding machine, the mold is exchanged for the next molded product when a predetermined number of products are molded. When molding a small number of products in large quantities, the entire mold is replaced.However, when molding small and large variety of products, such as small gears, wheels, or lenses, in small quantities, respectively, From the viewpoint of the efficiency of the mold exchange and the price of the mold, the mold is composed of a mother mold and a plurality of cores that are used by being interchangeably mounted on this mold. I have.

[0003] From the viewpoint of automating a molding operation performed continuously while exchanging such cores, a plurality of cores are accommodated in a core stocker, and cores are taken out of the core stocker to form a mother die. Attempts have been made to use a core exchange robot that attaches to a core mounting hole or vice versa. However, in this case, since the molding machine, the core stocker, and the robot are separate from each other, when they are combined for automation, it may take a lot of time to adjust the mutual relationship such as the positional relationship. In particular, for robots and core stockers, if the robot is a Cartesian coordinate system with relatively low degree of freedom, the positional relationship between the hand position and the core must be accurately determined. It takes time and effort to fix the unit. In addition, a separate core stocker or robot is disposed around the molding machine and interferes with the operation of other equipment and the operator.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a core changing robot which can easily automate core changing in a molding machine for core changing.

[0005]

The core exchange robot has a structure in which a base fixed on a platen of a molding machine, an arm movable with respect to the base, and a hand at the tip of the arm are provided.

A core accommodating portion for accommodating the replacement core is formed at a fixed position of the machine base.

[0007] The moving area of the hand includes the core accommodating portion and the mother die mounting hole attached to the platen.

[0008]

The structure in which the core accommodating portion for accommodating the replacement core is formed at a fixed position on the machine base of the core exchanging robot fixes the positional relationship between the hand and the core accommodating portion.

[0009]

EXAMPLE An example of an injection molding machine will be described as an example.

FIG. 1 shows a fixed platen 1 on which a core changing robot 2 is mounted.

A fixed mold 3a is attached to the fixed platen 1. This mold 3a is composed of a matrix 4a and a core mounting hole 5a.
a of the fixed side core 6a (FIG. 2).
In FIG. 1, the movable core 6b is attached to the fixed core 6a in a state of being integrally connected thereto, and the movable core 6b can be seen outside.

[0012] movable mold 3b is attached to the movable platen 7, composed of a matrix 4 b and core 6b of the mounted movable in its mounting hole 5b (FIG. 3, FIG. 5). Each of the molds 3 has a mold temperature control mechanism in the matrix 4 (a, b).

The core exchange robot 2 includes a machine base 8, a first arm 9, a second arm 10, and a hand 11, and is fixed on the upper surface of the fixed platen 1 with a stay 12 with the longitudinal direction of the machine base 8 in the left-right direction. Have been. The machine base 8 is formed in the front rail section 13 and the rear core accommodating section 14, and the rail section 13 is provided.
The ball screw / nut mechanism 15 is provided inside the rail portion 13.
And is driven by a servo motor 16. On the other hand, 4
A plurality (a plurality) of core accommodation holes 17 and a suction tool hole 19 in which one suction tool 18 is accommodated are provided. A temperature control liquid is introduced into the core accommodating portion 14, or the temperature around the core accommodating hole 17 is adjusted by an electric heater or the like.

Each of the core receiving hole 17 and the suction tool hole 19 has a half-hole shape, and
(Fig. 2) is accommodated in such a manner that about 1/3 of the core (6) fits in the form of being laid in the front-rear direction with the fixed core 6a as the front.
These are formed in a line in the longitudinal direction of the rail portion 13, and each of the receiving holes is provided with an engaging projection 20 (FIG. 9) so that the posture of the core 6 to be received is constant. Has been. Also, the opening / closing claw 30 of the hand 11
A space 21 for moving up and down with an open state (described later)
Are provided on both sides.

The first arm 9 is disposed in a direction perpendicular to the machine base 8 in a horizontal plane, that is, in the front-rear direction. The first arm 9 slidably holds the rail portion 13 with a front dovetail structure, and It is arranged inside the part 13 and is coupled to the ball nut 22 of the ball screw and nut mechanism 15 driven by the servo motor 16. Therefore, the first arm 9 moves left and right along the rail 13 when the servo motor 16 is driven. A sensor Sd for detecting the presence of the first arm 9 is provided at a position substantially at the center of the machine base 8 and directly above the core mounting hole 5a.
(FIG. 4) is arranged.

A second arm 10 is disposed on the first arm 9 in a vertical direction. The second arm 10 includes a sliding piece 23 and a cylinder device 24.
Is held by a dovetail groove structure so as to be slidable in the front-rear direction, and is moved to positions A, B, and C (FIG. 5) by a ball screw / nut mechanism 25 arranged inside the first arm 9. And position detection sensors Sa, Sb, S
c (FIG. 6). Above the sliding piece 23, a cylinder device 24 is rotatably supported by a shaft 26 in the front-rear direction. Reference numeral 27 denotes a servomotor that drives the ball screw / nut mechanism 25. The cylinder device 24 includes an air cylinder 28 and a piston 29. The air cylinder 28 is rotatable by a servo motor 30 from a vertical position to a substantially horizontal position (FIG. 4). It is installed as a front-back direction. The hand 11 is a grip-type centripetal gripping type having two fingers (two opening / closing claws 31) and is operated by air pressure.
Touch sensors Sf and Sb are provided on the front and lower surfaces of the opening / closing claw 31, respectively.
And a grip sensor Sg that issues a grip completion signal to the NC device when the opening / closing 31 grips the core 6.

The home position of the hand 11 is such that the first arm 9 is at the left end of the machine base 8 (the side opposite to the front), the second arm 10 is at the position A, and the cylinder device 24 is retracted to the upper end U position. It is a position that did. When the cylinder device 24 is contracted to the upper end, the lower surface of the hand 11 is higher than the upper end of the core 6 accommodated in the core accommodation portion 14,
Conversely, when the cylinder device 24 extends to the lower end, the gripping location of the hand 11 faces the position of the core mounting hole 5a of the master block 4a. The position where the cylinder device 24 is contracted to the upper end and the position extended to the lower end are determined by the detection switches Su,
Detected at SL. After all, the hand 11 moves the moving area to the core housing 14 and the matrix 4 attached to the fixed platen 1.
a includes a core mounting hole 5a.

The core 6 (FIG. 2) comprises a fixed core 6a and a movable core 6b. The fixed-side core 6a has a disk shape as a whole, is provided with a notch 32 on the front surface for maintaining a constant posture (at the time of storage), engagement grooves 33a on both side surfaces, and a rear parting surface PL. It has been. The movable-side core 6b has a cylindrical shape having two stages as a whole, and has the above-described fixed-side core 6a.
A front portion 34 having an outer diameter equal to the outside diameter thereof and a rear portion 35 having a smaller diameter than the front portion 34. The boundary between the front portion 34 and the rear portion 35 is a flange-like shoulder surface 36.
It has become. The front surface of the front portion 34 is a parting surface PL, and engagement grooves 33b are formed on both side surfaces. A fitting projection 37 is provided forward on the movable parting surface PL, and a fitting hole 38 is provided at a corresponding position on the fixed parting surface PL. Symbol 39
Is a molding cavity (FIG. 2), and reference numeral 40 is an eject pin (FIG. 3), which is arranged at the center of the movable core 6b.

The suction tool 18 (FIG. 10) is mounted on the movable core 6.
a front part 34 'and a rear part 35' having the same dimensions as b,
On the front surface, there is provided a suction unit in which a number of small-diameter suction disks 41 are assembled. The suction tool hole 19 is a portion corresponding to the movable core of the core receiving hole 17. A vacuum applying tube 42 connected to a vacuum pump is always connected to the suction tool 18.

As shown in FIG. 3, an air actuator 44 (a, b) having an engagement pin 43 (a, b) and a solenoid valve having a solenoid 45 are provided on the fixed-side matrix 4a and the movable-side matrix 4b. An engagement mechanism 47 (a, b) comprising a detection switch Ss (a, b) for detecting the presence of the core 46 (a, b) and the core 6 (a, b) is formed. Engagement pin 43
(A, b) is the engagement groove 3 whose tip is the core 6 (a, b).
3 (a, b) is engaged with the core 6 and is always urged in the engagement direction by the return spring 48. The solenoid 45 (a, b) is turned on and off by an NC device (numerical control device) provided in the injection molding machine. When the solenoid 45 is turned on, the solenoid valve 46 (a, b) is set to the state (1).
Through which the air actuator 44 (a, b)
Is supplied to the core 6 and the engagement pins 43 (a, b) are
It is retracted from the engagement groove 33 (a, b) of (a, b). When the solenoid 45 (a, b) is OFF, the solenoid valve 46 (a, b) is always returned to the state (2) by the return spring 49 (a, b).
The air supply to (a, b) is cut off and the air is released from this.

The injection molding machine equipped with the molds 3 (a, b) is of a normal type such as an electric type, and is equipped with the NC device as described above, and controls the temperature of the mold 3, opens and closes the mold, and measures the resin. , Injection and other injection molding processes are controlled as usual, and the NC unit has a core exchange mode that can be designated from the operation panel, and energizes and deenergizes the solenoids 45 (a, b).
A sequence program for instructing a core replacement procedure such as moving the movable platen 7 back and forth as part of driving of the ball screw / nut mechanisms 15 and 25 and core replacement operation;
And the data such as the use order of the core 6 based on the molding plan are programmed machine controller (PMC)
And a management control unit (NC).

When the molding using the core 6 this time has completed the predetermined amount, the core exchange operation is performed as follows by instructing the core exchange from the operation panel. In this case, the initial state is the core storage hole 17 of the core exchange robot 2.
(A, b) accommodates three spare cores 6 and a suction tool 18 in a suction tool hole 19. Spare core 6
In the figure, the auxiliary fixed side and movable side cores 6 (a, b) selected in advance in accordance with the forming work plan (plan) are integrally connected with the fitting projection 37 and the fitting hole 38. The cores 6a and 6b used this time are used for the matrix 4 (a and b), respectively.
Is installed. The core receiving portion 14 has a receiving hole 17 in which the core 6 (a, b) used this time is stored.
Are left empty.

In response to the core exchange command, first, the movable platen 7 is moved forward and the fixed and movable molds 3 (a, b) are moved.
Is brought into the mold touch state (FIG. 8), the movable-side engaging mechanism 47b is operated. That is, the solenoid 45b of the movable mold 3b is urged, and air is supplied to the air actuator 44b via the electromagnetic valve 46b, so that the engagement pin 4
3b is retracted from the engagement groove 33b of the movable core 6b, and the engagement between the movable master block 4b and the movable core 6b is released.

At this time, in the NC device, the PMC
The exchange of signals and instructions for confirmation and the transfer of data between these and the shared RAM and the input / output circuit, etc., and the transfer of data are performed mainly by the CPU for the NC and the CPU for the NC. Since there is no feature, description of this point is omitted. Hereinafter, the operation of each section will be mainly described.

Next, the movable platen 7 is retracted to the mold opening position. Since the movable-side core 6b is integrally attached to the fixed-side core 6a with the fitting protrusion 37, the movable-side core 6b is thereby pulled out of the movable-side mother die 4b's core mounting hole 5b to be fixed. It remains (FIG. 7).

After confirming that the movable platen 7 is in the mold opening position, the ball screw / nut mechanism 25 is extended, and the sliding piece 23 is moved to the rear B position while the cylinder device 24 is contracted. At the same time, ball screw and nut mechanism 1
5, the first arm 9 is moved right (forward) on the machine base 8 to the center core exchange position D (FIG. 4). Next, the cylinder device 24 is extended, the hand 11 is moved downward by the piston 29, and the second arm 10 is further advanced slightly so that the front surface of the opening / closing claw 31 is brought into contact with the shoulder surface 36 of the movable core 6b. Then, the touch sensor Sf is activated, and the opening / closing claw 31 is moved by the signal to move the rear portion 35 of the movable core 6b.
To grip.

The NC device drives the engagement mechanism 47a based on the grip completion signal from the grip sensor Sg. That is, the solenoid 45a is energized to set the solenoid valve 46a in the state (2).
The air actuator 44a is driven, and the engagement pin 43
a is retracted from the engagement groove 33a.

The sliding piece 23 of the second arm 10 is reverse to a further position C from the position B, lifting core 6 that is bunch withdrawn from the core mounting hole 5a of the stationary platen 1. When the completion of extraction is detected by detecting the position of the detection switch Sc, the cylinder device 24 contracts and lifts the extracted core 6, and then the ball screw / nut mechanism 25 causes
Advanced into position. Furthermore, ball screw / nut mechanism 1
5 is driven, the first arm 9 is moved in the left-right direction on the core accommodating portion 14 together with the second arm 10, and the held core 6 is positioned immediately above the core accommodating hole 17 of the vacant seat.

The position of the empty core receiving hole 17 is stored in the shared RAM of the NC unit at the time of the previous core replacing operation.
When the NC device drives the ball screw / nut mechanism 15,
When the completion of the contraction of the cylinder device 24 is confirmed by the detection switch Su, the PMC CPU
The position of the vacant core receiving hole 17 is read from the CPU, and the data and the data of the current position of the first arm 9 (central core replacement position) are transmitted to the NC CPU.
The required amount of movement of the first arm 9 required to make the position 1 the position of the empty core receiving hole 17 is calculated, and pulses based on the calculated amount are distributed to the servo circuit.

The cylinder device 24 is extended by the movement completion signal of the first arm 9, and the core 6 is fitted into the core receiving hole 17 immediately below. When the lower surface of the tip of the opening / closing claw 31 moves down the space 21 and reaches the bottom, the lowering of the cylinder device 24 is stopped by the signal from the touch sensor Sb on the lower surface of the opening / closing claw, and the opening / closing claw 31 of the hand 11 is opened. The child 6 is released into the core receiving hole 17. Core 6 is fixed core 6a
Due to the notch 20 formed in the lower part of the front surface of the boss and the engaging projection 20 at the corresponding location of the core receiving hole 17, the receiving hole 17 is always accommodated in the same posture. The engaging projection 20 is provided in each core receiving hole 17.

The cylinder device 24 moves to the upper end by the OFF signal of the grip sensor Sg, then the first arm 9 moves to the left end, and the hand 11 reaches the home position and stops. Thereby, the collection and storage of the core 6 used so far are completed.

Next, the NC device reads out the position of the core storage hole 17 in which the core 6 to be used next is stored from the data in the shared RAM according to the program, and performs NC control in the same manner as described above.
After processing inside the device, the first arm 9 is moved and the hand 1 is moved.
1 is changed from the home position to the position of the target new core 6, the cylinder device 24 is extended, the hand 11 is lowered, and the core 6 in the core receiving hole 17 is gripped at the rear portion 35 of the movable core 6b. Carry.

The cylinder device 24 contracts and the core 6 is pulled out of the core receiving hole 17. Then, the first arm 9 is D
The second arm 10 is moved from the position A to the position C, and the cylinder device 2 is moved thereat.
4 is extended to the lower end. When extension to the lower end is confirmed by the detection switch SL, the second arm 10 is advanced to the position B, and the fixed-side core 6a of the core 6 that has been gripped is inserted into the core-mounting hole 5a of the fixed-side mold 4a. (FIG. 6).

When the operation of the detection switch Ssa is confirmed, the solenoid 45a of the engagement mechanism 47a is deenergized, the air of the air actuator 44a is released via the electromagnetic valve 46a, and the engagement pin 43a is projected by the return spring 48a. Then, the fixed core 6a mounted is fixed to the matrix 4a. At the same time, using the operation of the detection switch Ssa as a signal, the opening / closing claw 31 of the hand 11 is opened and the core 6 is released. Next, upon confirming the OFF signal of the grip sensor Sg, the cylinder device 24 contracts, the hand 11 is raised from that position to the upper end, and then the second arm 10 is moved forward and the first arm 9 is moved left. Move and hand 11
To the home position. The movable core 6b is attached to the parting surface of the fixed mother block 4a together with the fixed core 6a because the fitting protrusion 37 is fitted in the fitting hole 38 of the fixed core 6a. (FIG. 7).

After confirming that the detection switch Su is ON, the movable platen 7 is advanced to the mold touch position. At the same time, the movable-side engaging mechanism 47b is driven, and the movable-side engaging pin 43b is retracted from the movable-side core mounting hole 5b as in the case of the fixed-side. Therefore, when the movable master block 4b is brought into the mold touch state with the fixed master block 4a,
The movable core 6b remaining on the parting surface of the fixed master block 4a is smoothly stored in the core storage hole 5b of the movable master block 4b (FIG. 8).

The detection switch Ssb is turned on, and the signal is used as a signal to deenergize the solenoid 45b, and the engagement pin 43b engages with the engagement groove 33b of the movable core 4b in the same manner as described above. The movable core 6b is fixed to the matrix 4b. Then, the movable platen 7 is retracted while separating the movable-side core 6b from the fixed-side core 6a, and the fixed platen 1,
It is assumed that a new core 6 (a, b) is mounted on each of the movable platens 7. This makes a new core 6
The mounting of (a, b) is completed.

In this manner, the replacement of the core 6 with the old one is completed. The operator cancels the core exchange mode by operating the operation panel, and returns the injection molding machine to the normal injection molding operation. If the core 6 is simply collected in the core accommodating portion 14, the operation will be substantially in the first half, and if the core 6 is newly installed, the operation will be substantially in the latter half.

The core changing robot 2 also has a function as a robot for taking out a molded product in a normal injection molding operation, and operates as follows. That is, first, as described above, the core replacement or the mounting of the core 6 is completed,
When the core exchange mode is canceled, the core exchange robot 2 is driven again by the NC device, and the hand 11 moves from the home position to the position of the suction tool hole 19 at the right end of the machine base 8 and descends to move the suction tool. 18 is gripped at the position of the rear portion 35 'and lifted to the upper end position. Then, the first arm 9 moves to the position D in the center of the machine base 8 and the second arm 1 moves.
When the injection molding operation in which the 0 moves to the position B and waits is activated,
After opening the mold in the molding cycle, the cylinder device 2
4 extends to the lower end, and the second arm 9 moves slightly forward to suck the molded product on the suction plate 41.

After the second arm 9 is slightly retracted by the amount described above to take out the product from the molding cavity 39, the suction disk 4
The product is dropped by releasing the adsorption of 1 and stored in the lower product box. When the product box is placed on the side of the injection molding machine, after taking out the product as described above, the cylinder device 24 contracts to the upper end, and the servo motor 30
The cylinder device 24 is pivoted about the axis 26 (FIG. 1) to a substantially horizontal position (FIG. 4, dashed line), and then the suction is performed after the cylinder device 24 is extended to transport the product to the position of the product box. It is released.

The above is one embodiment. The core exchange robot may be provided on the upper surface of the movable platen. Further, each arm and hand of the core exchange robot may be driven by fluid pressure such as air pressure, or may be a ball screw / nut mechanism using a servomotor. In the case of a ball screw / nut mechanism using a servomotor, the position of each arm and hand may be stored as a set value on a program instead of being detected by a sensor. The air actuator used in the above embodiment can be replaced by an electromagnetic solenoid. The core storage holes provided in the core exchange robot may be formed at fixed positions on the machine base, and are not limited to four.

[0041]

Since the core exchange robot has a function of a core stocker for accommodating a spare core, a mold having a mother die and a plurality of cores which are exchangeably mounted on the mother die can be used. In the injection molding machine to be used, the core exchange robot can be easily automated simply by mounting the core exchange robot on the platen. Moreover, at that time, troublesome adjustment such as the relationship between the hand and the storage position of the core in the robot is not required, and the work involved in the automation of core replacement is simplified.

Since the core changing robot itself has the core storing section, no extra space for the core changing device is required around the injection molding machine.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a portion of a fixed platen.

FIG. 2 is a perspective view of a core.

FIG. 3 is a plan view showing a mechanism, part of which is omitted.

FIG. 4 is a side view, partly in section, and partly omitted.

FIG. 5 is a simplified front view.

FIG. 6 is a simplified front view.

FIG. 7 is a simplified front view.

FIG. 8 is a simplified front view.

FIG. 9 is a plan view showing a core receiving hole.

[Explanation of symbols]

 2 core exchange robot 4 mother die 6 core 8 machine stand 9 first arm 10 second arm 11 hand 14 core accommodation part 17 core accommodation hole 18 suction tool 19 gripping device

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Susumu Ito 3580 Kobaba, Oshino-mura, Oshino-mura, Minamitsuru-gun, Yamanashi Pref. 3580 No. FANUC Co., Ltd.Product Development Research Center (72) Inventor Kikuo Watanabe Fukushima Co., Ltd.Product Development Research Center, Oshino-mura, Minamitsuru-gun, Yamanashi Prefecture 3580 Kobaba FANUC CORPORATION Product Development Laboratory (72) Inventor Toshio Matsukura 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Industrial Co., Ltd. (72) Inventor Kaoru 2-chome Hatagaya, Shibuya-ku, Tokyo 43-2 O Olympus Optical Co., Ltd. (72) Inventor Hiroshi Kubo 2-43-2, Hatagaya, Shibuya-ku, Tokyo Inside O-Limpus Optical Industry Co., Ltd. Kazunari Tokuda 2-43-2, Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd.

Claims (1)

(57) [Claims] 1. A core accommodating portion comprising a machine base fixed on a platen, an arm movable with respect to the machine base, and a hand provided at the tip thereof, and accommodating a replacement core at a fixed position of the machine base. Wherein the moving area of the hand includes a core accommodating portion and a core mounting hole of a mother die attached to the platen.