JPH0724752A - Method of extracting objective and extracting robot - Google Patents

Abstract

PURPOSE:To provide a method of extracting an objective and an extracting robot whose structure is simplified and lightened and which can handle the objective like a molded part in a short time. CONSTITUTION:A hold means 100 is moved straight in a first direction Z by engaging so as to set the hold means 100 for holding an objective F staying on a move body 2 with a guide means 45 in the first direction Z and rotating the guide means 45 in the first direction Z relating to the movement of the move body 2 and also the objective F can be extracted from the move body 2 by rotating and moving the hold means 100 in a second direction E, following the rotation of the guide means 45 in the first direction Z.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot for moving an object from a moving body, and is particularly suitable for taking out an object such as a molded article from a die such as a moving die of a molding machine. The present invention relates to a method and a robot for taking out an object.

[0002]

2. Description of the Related Art A conventional injection molding machine includes, for example, a movable mold and a fixed mold. The molded product molded between the movable die and the fixed die is taken out from the movable die by a take-out machine which is a robot when the movable die separates from the fixed die.

Specifically, this type of take-out machine is equipped with a swing-type arm that holds a molded product in a detachable manner. This swing-type arm swings or rotates in a certain direction when the movable mold is separated from the fixed mold and the molded product is taken out, and enters between the movable mold and the fixed mold to hold the molded product, and It swings in the opposite direction and takes out the molded product from between the movable mold and the fixed mold.

[0004]

There are the following types of such take-out machines, but each of them has problems. (1) In a system in which the swing type arm is installed in the movable type, the weight of the swing type arm is added to the weight of the movable type, so that when the molded product is taken out, the high speed of the movable type is taken out. I can't move. In addition, since the weight is heavy, the stopping accuracy of the movable mold of the molding machine is poor, which adversely affects the dimensional accuracy of the product, and the life of the molding machine is short.

(2) In the swing type arm fixed to the movable type (Martin type), the swing type arm 200 is swung as shown by an arrow R in FIG. This swing is performed by the cylindrical cam 2 shown in FIG.
It is performed by guiding by the cam groove 250 of 40.

In the system in which the swing type arm of this kind is fixed to the movable type, the total additional weight Wt added to the movable type can be expressed by Formula 1.

[0007]

[Equation 1]

In Expression 1, We represents the equivalent weight when the swing type arm 200 shown in FIG. 4 swings. W1 is a swing-type arm 200
The weight of the holding part 210 of the molded product is shown, and W2 shows the weight of the base 220 of the swing-type arm 200.

The equivalent weight We of the swing type arm 200 due to the Martin type swing is obtained as follows. First, the moment of inertia I is calculated by Equation 2.

[0010]

[Equation 2]

In Equation 2, l1 is the length of the arm 200 and d1 is the diameter of the base 220. Next, the kinetic energy T is obtained by the mathematical formula 3.

[0012]

[Equation 3]

In Equation 3, as shown in FIG. 5, there is a relationship of the cam function θ = f (x) of the cylindrical cam 240.

Me represents the mass of the swing-type arm 200 converted into linear motion. The mass Me of the swing-type arm 200 converted into linear motion is given by
Can be expressed as

[0015]

[Equation 4]

As a result, the equivalent weight We when swinging can be expressed by Equation 5. In Equation 5, θ1 is shown in FIG.
The cam guide angle of the cam groove 250 of the cylindrical cam 240 shown in FIG. The cam guide angle θ1 is 90 degrees.

[0017]

[Equation 5]

The total added weight Wt added to the movable die, including the obtained equivalent weight We, is obtained by the above-mentioned formula 1. In the method of (2), there is an additional weight equivalent to that added to the movable die by the swing motion as described above, and the movable die cannot move at high speed as in the method of (1). There's a problem.

(3) Further, in the system shown in FIGS. 6 to 8, the flange 290 of the swing type arm 270 is
It is rotatably supported by a nut 310 via a bearing 300. In other words, swing type arm 2
The flange 290 of 70 is indirectly set to the nut 310 via the bearing 300.

This nut 310 is used for the ball screw 3
The nut 310 is engaged with the nut 15, and the motor 320 is driven to rotate the ball screw 315 and move the nut 310.

When the nut 310 moves, the cam follower 330 of the flange 290 is guided along the cam groove 350 of the cylindrical cam 340 shown in FIG. 8, and the swing type arm 270 swings. it can. The nut 310 is fixed to the slider 380, and the slider 380 is guided by the slider guide 390. With the slider 380 and the slider guide 390, the nut 310 is moved to the ball screw 315.
It is configured to always maintain a constant angle regardless of the rotation of.

Therefore, as the cam follower 330 is guided along the cam groove 350, the swing arm 270 is swung as shown in FIG. 6, and the take-out head 370 of the swing arm 270 moves.
It is designed to carry out molded products from scratch.

In this system, in order to shorten the time for taking out the molded product, it is desired that the take-out head 370 opens the movable die 360 and moves it between the movable die and the fixed die early while moving. However, in this system, the cylindrical cam 34
Since the pressure angle from 0 to the cam follower 330 becomes small, the rotation speed of the take-out head 370 cannot be increased, and it cannot be inserted between the movable die and the fixed die too early.

Further, since the bearing is required, the structure is large and complicated, the weight cannot be reduced, and the molded product cannot be handled in a short time.

In order to solve the above problems, the present invention can simplify the structure and reduce the weight, and can take out an object such as a molded article in a short time and a method of taking out the object. The purpose is to provide a robot.

[0026]

This object is, in the present invention, a method for taking out an object in a moving body from the moving body, and a holding means for holding the object in the moving body. Is engaged with the guide means in the first direction, and the guide means in the first direction is rotated in association with the operation of the moving body, thereby linearly moving the holding means in the first direction. At the same time, the holding means is rotationally moved in the second direction in accordance with the rotation of the guide means in the first direction, whereby the object is taken out from the moving body.

Further, in the present invention, the object is a robot for taking out the object from a movable body which preferably includes the object, and a holding means for holding the object in the moving body. And moving means for taking out the object from the moving body by moving the holding means, wherein the moving means is set by engaging the holding means, and is related to the operation of the moving body. The first guide means for linearly moving the holding means in the first direction by rotating the holding means and the holding means.
And a second guide means that rotates and moves in a second direction with the rotation of the guide means in one direction.

Further, in the present invention, preferably, the first guide means is a ball screw, the holding means has a nut, and the ball screw and the nut are engaged with each other. Further, in the present invention, preferably, the second guide means is a cam and a cam follower that meshes with the cam. And in the present invention,
Preferably, the movable body is a movable mold of a molding machine.

[0029]

According to the above construction, the holding means for holding the object on the moving body is set by directly engaging with the guide means in the first direction. Therefore, by rotating the guide means in the first direction in relation to the operation of the moving body without passing through the bearing, the holding means is linearly moved in the first direction, and the holding means is moved in the first direction. The object is taken out of the moving body by rotating and moving in the second direction with the rotation.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the examples described below are suitable specific examples of the present invention, and therefore, various technically preferable limitations are given, but the scope of the present invention particularly limits the present invention in the following description. Unless otherwise stated, the present invention is not limited to these modes.

FIG. 1 is a view showing a preferred embodiment of the take-out robot of the present invention, and FIG. 2 is a side view of the take-out robot of FIG. The take-out robot 290 in FIGS. 1 and 2 is used to take out a molded product F molded in the injection molding machine 10 in this example.

First, the injection molding machine 10 will be described. The injection molding machine 10 has a movable platen 12 and a fixed platen 14. The movable platen 12 includes a movable mold 2, and the fixed platen 14 includes a fixed mold 4. This movable plate 12 is a drive means 1
By 30 it is possible to move in the direction of arrow Z, which is the first direction.

On the other hand, the fixed die 4 has a passage (not shown) formed therein, through which the material to be molded can be injected into the cavity 16 between the movable die 2 and the fixed die 4.

The molded product F is, for example, a disk-shaped molded product and is used as a rotary information recording medium such as an optical disk or a magneto-optical disk.

Next, the take-out robot 90 will be described. 1 and 2, the take-out robot 90 is
A take-out arm 100 as holding means for detachably holding a molded product F which is an object, and the take-out arm 1
A moving means 92 for taking out the molded product F from the movable die 2 of the molding machine 10 by moving 00, a position sensor 60 for detecting the position of the movable plate 12, and a control device 20 are provided.

First, the take-out arm 100 will be described. As shown in FIGS. 1 and 2, this take-out arm 1
00 is a nut 50, a base portion 101, and an extension portion 102.
And the take-out head 104.

As shown in FIG. 2, this extension 102
Are formed to be inclined at a predetermined angle with respect to the base 101. At the tip of the extension portion 102, a take-out head 104 that detachably holds the molded product F is provided. The take-out head 104 can detachably hold the molded product F by, for example, vacuum suction.

The base 101 is directly fixed or fixed to the nut 50. The nut 50 engages with a ball screw 45 described later.

Next, the moving means 92 will be described. As shown in FIGS. 1 and 2, the moving means 92 is, as described above, for moving the molded product F from the moving mold 2 or removing it and moving it to another place. The moving unit 92 includes a drive unit 110. By driving the drive unit 110, the take-out arm 100 can be linearly moved in the first direction Z and can be swung, rotated, or swung in the second direction E. There is.

As shown in FIG. 1, the moving means 92 moves the take-out arm 100 along the Z direction (first direction) by a predetermined stroke S, and at the same time, the moving means 92.
2, the take-out arm 100 is swung in the rotation direction E (second direction) by a predetermined swing angle α,
Alternatively, it can be rotated or swung.

In this way, the moving means 92 can take out the molded product F from the movable mold 2 by linearly moving the take-out arm 100 in the first direction Z and rotationally moving it in the second direction E. It is like this.

The drive unit 110 of the moving means 92 has the following structure. A pulley 42 is fixed to an output shaft 41 of the motor 40, and a belt 44 is set between the pulley 42 and another pulley 43. A ball screw 45 is connected to the pulley 43, and by driving the motor 40, the ball screw 45 can be rotated in the arrow R direction. In other words, the rotation direction of the ball screw 45 is counterclockwise when viewed from the left end of the ball screw 45.

One end and the other end of the ball screw 45 are supported by support members 46 and 47. As shown in FIG. 1, the nut 50 of the take-out arm 100, which is a holding means, is directly engaged with the ball screw 45. The ball screw 45 is a first guide unit that linearly moves and guides the take-out arm 100 and the nut 50 in the first direction Z.

When the ball screw 45 is rotated counterclockwise as viewed from the left end of the ball screw 45, the nut 50 integrated with the take-out arm 100 is
In FIG. 1, it can move to the left along the first direction Z.

The nut 50 has the above-mentioned take-out arm 1
00 base 101 is fixed. Further, a support member 52 is fixed to the nut 50, and a cam follower 54 is set on the support member 52.

The cylindrical cam 60a is a ball screw 45.
Are arranged in parallel with. The cam groove 6 is provided on the cylindrical cam 60.
2 is formed. The cam follower 54 is guided in the cam groove 62. This cam groove 62
1 has a first cam groove guide portion 70 and a second cam groove guide portion 72, as particularly shown in FIG.

As shown in FIG. 1, the first cam groove guide portion 70 is formed so as to extend obliquely downward to the left. Also, the second
As shown in FIG. 1, the cam groove guide portion 72 is formed in a horizontal direction or a direction parallel to the ball screw 45. The first cam groove guide portion 70 and the second cam groove guide portion 72 are smoothly connected. The cylindrical cam 60 and the cam follower 54 form a second guide unit that guides the take-out arm 100 and the nut 50 by rotationally moving in the second direction E.

The position sensor 60 is a linear position detecting sensor such as a linear encoder. That is, the position sensor 60 can detect the position of the movable die 2 with the fixed die 4 as a reference.

The control device 20 comprises a drive means 1 for the movable platen 12.
It is connected to the motor 30 and the motor 40 and controls the driving means 130 and the motor 40. The position sensor 60 is connected to the control device 20, and the position information of the movable die 2 obtained by the position sensor 60 is given to the control device 20.

Operation Next, steps ST1 to ST12 shown in the flowchart of FIG.
It will be described based on. First, in step ST1,
The movable platen 12 and the fixed platen 14 of FIG. 1 are closed. At this time, the resin is injected into the cavity and the molded product F is molded.

When the movable platen 12 and the fixed platen 14 are closed, the take-out arm 100 is at the initial position A indicated by the chain double-dashed line, as shown in FIGS. 1 and 2.
Is located in. In this initial state, the cam follower 54 of FIG. 1 is located in the first cam groove guide portion 70 of the cam groove 62.

The drive means 13 is instructed by the controller 20.
When 0 is driven, the movable platen 12 starts to separate from the fixed platen 14 (step ST2). When the movable platen 12 starts to separate from the fixed platen 14 in this manner, the position sensor 60 outputs the encoder value as a pulse. Therefore, the control device 20 obtains the encoder value which is the position information of the movable platen 12 from the position sensor 60.

On the other hand, according to a command from the control device 20, the motor 40 is driven at the same time as or when the driving means 130 is driven, and the rotational force of the motor 40 causes the two pulleys 42, 43 and the belt 44 to rotate. Via the ball screw 45, the ball screw 45 rotates in the direction of arrow R in FIG. Then, the control device 20 detects the position information of the movable mold 2 detected by the position sensor 60,
A target value that is a target position to which the take-out arm 100 is desired to be moved is calculated (step ST3).

Based on this target value, the control device 20
A servo control signal is given to the motor 40, and the motor 40 is servo-controlled by the rotation angle corresponding to the target value (step ST4). By the servo control drive of this motor 40,
The ball screw 45 rotates in the R direction in FIG. Therefore, the take-out arm 100 and the nut 52 move along the left direction (the arrow Z direction) which is the first direction in FIG. 1 to move from the state of the position A to the direction of the position B, and at the same time, the take-out arm 100 and the nut 52. Position A along the clockwise direction which is the second direction E in FIG.
It rotates in the direction of position B from the state.

At this time, the cam follower 54 moves from the first cam groove guide portion 70 of FIG. 1 to the second cam groove guide portion 72 via the connecting portion 73. That is, in FIG. 1, the cam follower 54 moves from the upper right to the lower left. The cam follower 54 is connected to the second cam groove guide portion 7 via the connecting portion 73.
After entering 2, take-out arm 100 and nut 50
Does not swing or rotate, but only moves to the left (the arrow Z direction), which is the first direction in FIG. 1, and the take-out arm 100 and the nut 50 move to the position C in FIG.

After that, the take-out head 104 is shown in FIG.
As shown in FIG.
When the product contacts the molded product F (step ST5), the eject pin (not shown) operates to discharge the molded product F from the movable mold 2 (step ST6). Otherwise, when the take-out head 104 has not arrived at the molded product F, the process returns to step ST3. The discharged molded product F is adsorbed and held on the take-out head 104 side (step ST
7).

When it is confirmed that the molded product F is adsorbed and held on the take-out head 104 side, the control device 20
A signal is given to the driving means 130 to move the movable platen 12 to the fixed platen 1.
4 side to start closing the molding machine 10 (step ST
8). The movable platen 12 moves to the fixed platen 14 side to move to the molding machine 10.
When is started to be closed, the position sensor 60 provides the controller 20 with position information of the movable platen 12 which is an encoder value.

The controller 20 calculates a target value corresponding to the target position to which the mounting arm 104 and the nut 50 are to be moved, from this position information (step ST9). Then, the control device 20 gives a servo position control signal to the driving unit 130 to control the servo position of the motor 40 (step ST10).

The motor 40 is driven by this servo position control signal.
Is rotated in the reverse direction, the take-out arm 100 and the nut 50
Follows the reverse order of that described above. That is, FIG.
The cam follower 54 moves from the second cam groove guide portion 72 to the first cam groove guide portion 70 via the connecting portion 73. That is, in FIG. 1, the cam follower 54 moves from the lower left to the upper right.

The cam follower 54 has the second cam groove guide portion 7
While being guided by 2, the take-out arm 100
Moves only to the right in FIG. 1, and does not swing or rotate.

The cam follower 54 has the second cam groove guide portion 7
When guided by 2, the take-out arm 100 further moves rightward in FIG. 1 and rotates in the direction from position B to position A in FIGS. 1 and 2. Thereby, the take-out head 104 of the take-out arm 100
With the molded product F being held, it comes out between the movable mold 2 and the fixed mold 4, and the take-out arm 100 reaches the position A.

When the movable platen 12 of the molding machine 10 is closed (step ST11), the molded product F is ejected from the ejection arm 100 (step ST12), and a series of ejection operations is completed.

As described above, in the embodiment of the present invention, the so-called take-out arm 100 is directly fixed to the ball screw or the nut 50 screwed to the ball screw 45. For this reason, the cam follower 54 has the cam groove guide portion 7
The direction of the force applied to 0 (hereinafter referred to as the pressure angle) is not only the first direction Z as in the conventional case but also the resultant force of the rotation direction R of the ball screw 50. As long as the component of the force related to the moving direction R matches the traveling direction of the cam follower 54, the swing of the take-out arm 100 can be greatly swung even if the movement in the first direction Z is a small amount. .

Therefore, in order to make the force component relating to the rotating direction R coincide with the traveling direction of the cam follower 54, the take-out arm 100 overlaps the rotating operation in the arrow R direction and the linear operation in the arrow Z direction. Pay attention to the part you do,
The rotation direction R of the takeout arm 100 may be aligned with the direction of spiral rotation progress (hereinafter referred to as turning) of the ball screw or the spiral groove of the ball screw 50. Specifically, when the arm 100 is rotated rightward with respect to the linear traveling direction Z, the ball screw or the ball screw 45
When the spiral groove is formed in the right turning direction and the arm 100 is rotated left with respect to the straight traveling direction Z, the screw groove of the ball screw or the ball screw 45 may be set in the left turning direction.

After the molding machine started the mold opening operation, the take-out head entered early between the movable mold and the fixed mold,
After that, an operation that follows the movable linear motion can be performed. Then, even during the mold opening operation, the taking out operation of the molded product can be performed, the taking out time in the injection molding cycle can be shortened, and the production capacity is increased. Since a single ball screw can generate rotational and linear motion power, it has a simple structure and high reliability.

In the conventional method, there is a problem of the pressure angle between the cylindrical cam and the cam follower, so that it is difficult to use a cam that allows the take-out head to enter the mold at an early stage of mold opening. On the other hand, in the embodiment of the present invention, the take-out head can be inserted into the mold very early. As described above, since the pressure angle between the cylindrical cam and the cam follower is small and there is no restriction on the pressure angle, even if the movement in the first direction is a small amount, the swing of the takeout arm can be swung greatly. This is because it is possible to shorten the linear motion section in which the takeout arm swings.

Further, unlike the conventional example shown in FIGS. 6 to 8, a slider and a slider for keeping the nut at a constant angle regardless of the rotation of the ball screw without using a bearing. You don't need a guide. Therefore, the structure of the take-out robot can be simplified correspondingly, and the weight and the size can be reduced.

The present invention is not limited to the above embodiment. For example, the present invention is applicable not only to molded articles as objects, but also to objects in other fields. The first guide means is not limited to the ball screw or the ball screw, and other means can be applied. Further, the shape of the cam groove of the cylindrical cam constituting the second guide means can be set arbitrarily.

[0069]

As described above, according to the present invention, it is not necessary to use a bearing, which has been conventionally required, and the structure can be simplified and the weight can be reduced. It can be handled in a short time.

[Brief description of drawings]

FIG. 1 is a view showing a preferred embodiment of a robot of the present invention and a molding machine.

FIG. 2 is a side view of the molding machine and robot shown in FIG.

FIG. 3 is a flowchart showing an operation example in the embodiments of FIGS. 1 and 2.

FIG. 4 is a diagram showing a conventional robot.

5 is a diagram showing the shape of a cam used in the conventional example of FIG.

FIG. 6 is a side view showing another conventional robot.

7 is a front view of the conventional robot of FIG.

8 is a diagram showing the shape of a cam in the conventional robot of FIG.

[Explanation of symbols]

 2 movable mold 4 fixed mold 10 molding machine 12 movable plate 14 fixed plate 16 cavity 20 controller 40 motor 45 ball screw (first guide means) 54 cam follower (second guide means) 60 position sensor 60a cylindrical cam ( Second guide means) 62 guide groove 90 take-out robot 92 moving means 100 take-out arm 104 take-out head 130 drive means F molded product (object) A, B position

Claims (5)

[Claims] 1. A method of taking out an object on a moving body from the moving body, wherein holding means for holding the object on the moving body is set by engaging with a guide means in a first direction. By rotating the guide means in the first direction in association with the operation of the moving body, the holding means is linearly moved in the first direction, and the holding means is moved by the guide means in the first direction. A method of taking out an object, wherein the object is taken out of the moving body by rotating and moving in a second direction with rotation. 2. From a movable body equipped with an object,
A robot for taking out the object, comprising: holding means for holding the object in the moving body, and moving means for taking out the object from the moving body by moving the holding means, The moving means includes a first guide means that linearly moves the holding means in the first direction by rotating the holding means in association with the movement of the moving body, and the holding means. And a second guide means that rotates and moves in a second direction in accordance with the rotation of the guide means in the first direction. 3. The object take-out robot according to claim 2, wherein the first guide means is a ball screw, the holding means has a nut, and the ball screw and the nut are engaged with each other. 4. The object take-out robot according to claim 2, wherein the second guide means is a cam and a cam follower engaged with the cam. 5. The movable body is a movable mold of a molding machine,
The object taking-out robot according to any one of claims 2 to 4.