JPH04274832A - Blank sucking up device - Google Patents

Abstract

PURPOSE:To allow the shockless suction and transfer of a blank with the blank sucking up device and to speed up the entire part of operations. CONSTITUTION:The blank sucking up device including a vacuum cup (11) and a lifting means (20) is constituted by forming the lifting means (20) of a servo mechanism including a driving shaft (21), etc., and providing an upper limit height setter (34), an upper limit approach height setter (35), a lower limit approach height setter (36), and an suction detector (37) and providing a control means (30) which outputs a control signal S3 for lifting a vacuum cupthe upper limit approach height HL or above and at a highspeed Vh at the other heights.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blank suction device. Mainly used as a destack device for press machines.

0002

2. Description of the Related Art FIG. 4 shows an example of a destacking device equipped with a blank suction device. In the figure, 2 is a pallet that stores a large number of stacked blanks W, 3 is a lifter that pushes up the blanks W above the holding claw 5, and 4 is a magnetic force that separates and holds the blanks W one by one by magnetic force. Separation means, 1 is 1 delivered from the blank suction device
This conveyance means is formed from a magnetic conveyor or the like that conveys the blanks W to a press machine or the like (not shown) in the X direction. The surface height of the uppermost blank W held by the magnetic separation device 4 is the lower limit height LLL, and the conveyance means 1
The height delivered to is the upper limit height HHL.

[0003] Here, the blank suction device comprises a suction means 10 including a vacuum cup 11, an air box 12, an air hose 13, etc., and an elevating means 20. The elevating means 20 is for elevating the vacuum cup 11 between the upper limit height HHL and the lower limit height LLL in the direction of arrow Y,
It is generally composed of a cylinder device 29 having the relevant stroke. The stroke of the cylinder device 29 is such that the vacuum cup 11 can be lowered to the position of the holding claw 5 when replacing the pallet 2.

[0004] Therefore, the cylinder device 29 is moved downward to press the vacuum cup 11 against the blank W at the lower limit height LLL. After the vacuum cup 11 adsorbs the blank W, if the cylinder device 29 is then raised to the upper limit height HHL, only one blank W can be sucked up and delivered to the conveying means 1.

[0005]

[Problems to be Solved by the Invention] Nowadays, it is applied to various blanks W due to diversification, and even higher speeds are desired. It has been pointed out that it is becoming impossible to meet these demands.

That is, the general operating speed of the cylinder device 29 is at a limit where it cannot keep up with the further increase in speed. In principle, the stroke of the cylinder device 29 only needs to be the distance between the upper limit height HHL and the lower limit height LLL. On the other hand, it is difficult to further improve the speed control characteristics of the cylinder device 29. Therefore, if there is a delay in the electromagnetic valve operation time or the operation of the cylinder device 29 itself, the vacuum cup 11 will force the blank W downward more strongly than necessary due to coasting. As a result, the magnetic separation means 2
Even if one blank W is separated at step 4, the vacuum cup 11 will adsorb the two blanks W, making smooth suction impossible. This problem becomes more serious as the operating speed of the cylinder device 29 increases.

On the other hand, the operating speed characteristics of the cylinder device 29 also cause problems in the blank W suction process. For example, if the rising speed is not completely reduced at the upper limit height HHL, the blank W will be strongly collided with the conveying means 1, and the blank W will drop or be bruised due to the reaction.

[0008] An object of the present invention is to provide a blank suction device that can pick up and transfer blanks without shock and can greatly increase the overall speed.

[0009]

[Means for Solving the Problems] The invention as claimed in claim 1 provides a vacuum cup for sucking blanks, and a vacuum cup that is placed between the lower limit height at which the blank is held and the upper limit height at which the blank is delivered. A blank suction device comprising: a lifting means for raising and lowering the vacuum cup; An upper limit height setting device, an upper limit approach height setting device, a lower limit approach height setting device, and a suction detector are provided, and the descending speed of the vacuum cup is switched from high speed to low speed at the lower limit approach height, and the rising speed is changed. The present invention is characterized in that a control means is provided for outputting a control signal for switching from adsorption of the blank to a high speed up to the upper limit approach height and to a lower speed at the upper limit approach height.

[0010] Furthermore, the invention according to claim 2 is characterized in that the lower limit approach height setter is attached to the drive shaft for engaging with the blank held at the lower limit height and detecting the actual distance to the blank. It is characterized by being formed from a distance detector.

[0011]

According to the first aspect of the invention, an upper limit height, an upper limit approach height, and a lower limit approach height are set in each setting device in advance. here,
When the drive starts, the control means drives and controls the servo mechanism. That is, the vacuum cup is lowered at high speed and switched to low speed at the lower limit approach height. Therefore, the vacuum cup can be soft-touched to the blank at the lower limit height and can reliably suction one blank. After this suction, the vacuum cup is raised at high speed until it reaches the upper limit approach height, and then switched to low speed. The sucked-up blank is delivered to a conveying means or the like without shock at the upper limit height. Therefore,
By setting the upper limit approach height and the lower limit approach height to appropriate and small values, suction and delivery can be performed without shock, and the overall speed can be increased.

Further, in the invention of claim 2, since the lower limit approach height setting device is formed of a distance detector that descends together with the drive shaft, even if there is a disturbance such as a change in the blank loading height, it can be absorbed. Blanks can be adsorbed without shock, and there is no need to manually set the lower limit approach height. Moreover, since the range of high-speed descent can be expanded, even higher speeds can be achieved.

[0013]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. (First Embodiment) As shown in FIG. 1, this blank suction device has a lifting means 20 formed from a servo mechanism, and is provided with setting devices 34, 35, 36, 37 and a control means 30.
The structure is such that the blank W can be picked up and transferred without shock, and the overall speed can be significantly increased. This embodiment is intended to be used by being incorporated into the destack device shown in FIG. 4 mentioned above. Therefore, the same reference numerals are given to the same or common components as in the conventional example, and the explanation thereof will be simplified or omitted.

In FIG. 1, the elevating means 20 is formed of a servo mechanism instead of the cylinder device 29. That is, the drive shaft 21 is provided with a rack 22 and is held so as to be vertically and slidably movable. Guide bar 25 and guide 26
This is to reduce the mass of the drive shaft 21 while ensuring stable and reliable sliding. A pinion 23 rotated by a motor 24 is meshed with this rack 22 . Therefore, if the motor 24 is controlled to rotate in a predetermined direction, the drive shaft 21
In other words, the vacuum cup 11 can be raised and lowered.

Next, the upper limit height setting device 34, the upper limit approach height setting device 35, and the lower limit approach height setting device 36 set the delivery height to the conveying means 1 at the upper limit height HHL and the upper limit height setting device 36, which is the upper limit height setting device 34, upper limit approach height setting device 35, and lower limit approach height setting device 36. When the height of the blank W is the lower limit height LLL, the values of the upper limit height HLL, the upper limit approach height HL slightly below the upper limit height HHL, and the lower limit approach height LL slightly above the lower limit height LLL, respectively. This is to set the . Upper limit height HHL
The equivalent value signal S5, the upper limit approach height HL equivalent value signal S4, and the lower limit approach height LL equivalent value signal S2 are input to the control panel 31.

However, the signal at the lower limit height LLL is not set by a setting device, but by a suction detector 37 built in the air box 12 that generates a suction signal when the blank W is suctioned by the vacuum cup 11. It is obtained as signal S3. Furthermore, the rotation speed and rotation angle of the motor 24 are as follows:
It is detected as the detection signal d of the encoder 33, and the control panel 3
1 is input.

Here, the control means 30 includes a control panel 31 that outputs a control signal S1 based on each input signal, and a control panel 31 that outputs a control signal S1 based on each input signal.
and a driver 32 that controls the rotation of the motor 24 at a high speed Vh and a low speed Vl based on the following. Specifically, the descending speed V of the vacuum cup 11 is switched from high speed Vh to low speed Vl at the lower limit approach height LL, and the ascending speed V is changed to high speed Vh from sucking the blank W to the upper limit approach height HL.
and outputs a control signal S1 for switching to low speed Vl at the upper limit approach height HL.

Next, the operation will be explained with reference to FIG. The control panel 31 outputs a lowering control signal S1 at high speed Vh to the driver 32 based on the blank suction command. Then, the motor 24 sets the high speed Vh as the target value,
As shown in FIG. 2, the drive shaft 21 rapidly rises to a high speed
Descend at The encoder 33 outputs a detection signal d.

When the vacuum cup 11 reaches the preset lower limit approach height LL (signal S2), the control panel 31 (control means 30) changes the control signal S1 to the low speed Vl.
Switch to. Therefore, the motor 24 is decelerated and lowers the vacuum cup 11 at a low speed Vl below the lower limit approach height LL. Therefore, vacuum cup 11
performs a soft touch on the blank W at the lower limit height LLL or within a certain height in the vertical direction around this lower limit height LLL. Therefore, the blank W is attracted to the vacuum cup 11 which has been evacuated in advance.

Then, the suction signal S3 is output from the suction detector 37.
is issued, the control panel 31 changes the control signal S1 to high speed V.
Switch to h increase control. As a result, the vacuum cup 11 is moved up to the upper limit approach height HL by the blank W at high speed Vh.
suck up. When the upper limit approach height HL is reached, the control panel 31 determines that the vacuum cup 11 has reached the upper limit approach height HL based on the setting value of the upper limit approach height setting device 35 (signal S4) and the detection signal d from the encoder 33. Automatically determines
Control signal S1 is switched to low speed Vl. Therefore, the motor 24 is rapidly decelerated and the vacuum cup 11 is slowly raised.

[0021] Thus, the attracted blank W is delivered to the magnetic conveyor of the transport means 1 while being soft-touched at the upper limit height HHL. At the upper limit height HHL, the motor 24 is stopped.

According to this embodiment, the elevating means 20 is formed of a servo mechanism including a drive shaft 21, a motor 24, etc., and each setting device 34, 35, 36, 37 and a control means 30 are provided. , the vacuum cup 11 forming the adsorption means 10 is raised and lowered at a low speed Vl below the lower limit approach height LL and above the upper limit approach height HL, and at a high speed Vh otherwise. Transfer to 1 can be performed without shock, and the entire process can be made faster.

[0023] Also, the lower limit height LL for adsorbing the blank W
L is not set by a setting device, but the suction detector 37 detects that the vacuum cup 11 has actually suctioned a blank W, so that two blanks W may be suctioned due to insufficient descent or two blanks W due to overstroke. Adsorption etc. can be avoided.

(Second Embodiment) As shown in FIG. 3, this embodiment has the same basic configuration as the first embodiment shown in FIG. It consists of a distance detector which is attached to the blank W and interacts with it to detect the actual distance to the blank W. That is, in the first embodiment, the lower limit approach height LL is set in advance, and the height LL
It was determined in the control panel 31 based on the detection signal d of the encoder 33 whether or not the actual distance between the vacuum cup 11 and the blank W (DS in FIG. possible) is detected (detection signal DL),
This height is automatically set as the height DLL corresponding to the lower limit approach height LL.

Therefore, the control means 30 detects the detection height D which is one step lower than the lower limit approach height LL in the first embodiment.
As shown by the two-dot chain line in Fig. 2, Vh descends at high speed until LL.
Control signal S to switch to low speed Vl at detection height DLL
Outputs 1. The distance detector is selected from an optical type using a laser beam, a capacitance type, and the like.

[0026] In this second embodiment, in addition to achieving the same effects as the first embodiment, such as shockless adsorption and increased overall speed, the height of the blank W, which is held below, is much closer to that of the first embodiment. Since Vh can be lowered at high speed to (DLL), even higher speed can be achieved.

[0027]

[Effect of the invention] As described above, according to the invention of claim 1,
The elevating means is formed of a servo mechanism including a drive shaft, a motor, etc., and is equipped with an upper limit height setter, an upper limit approach height setter, a lower limit approach height setter, and a suction detector. Since the configuration is provided with a control means that raises and lowers the vacuum cup at a low speed above the height and at a high speed at other times, the blank suction and delivery can be performed without shock, and the overall speed can be significantly increased.

[0028] Furthermore, according to the invention of claim 2, claim 1
In addition to the effects of the invention, since the configuration is such that the speed is switched to low speed at a detection height that is one step lower than the lower limit approach height, the high-speed descending range is expanded and even higher speeds are achieved.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation.

FIG. 3 is an overall configuration diagram showing a second embodiment.

FIG. 4 is a diagram for explaining a conventional blank suction device incorporated in a destack device.

[Explanation of symbols]

1 Transport means 2 Pallet 3 Lifter 4 Magnetic separation means 5 Holding claw 10 Adsorption means 11 Vacuum cup 12 Air box 13 Air hose 20 Lifting means 21 Drive shaft 22 Rack 23 Pinion 24 Motor 25 Guide bar 26 Guide 29 Cylinder device 30 Control means 31 Control panel 32 Doll driver 33 Encoder 34 Upper limit height setter 35 Upper limit approach height setter 36 Lower limit approach height setter (distance detector) 37 Adsorption detector W Blank HHL Upper limit height HL Upper limit approach height LL Lower limit approach height LLL Lower limit height DLL Detection height

Claims (2)

[Claims] Claim 1: The vacuum cup is formed to include a vacuum cup for sucking blanks, and a lifting means for raising and lowering the vacuum cup between the lower limit height at which the blank is held and the upper limit height at which the blank is delivered. In the blank suction device, the elevating means is formed of a servo mechanism including a drive shaft that holds the vacuum cup, a motor that applies elevating power to the drive shaft, and an upper limit height setting device and an upper limit approach height. A height setting device, a lower limit approach height setting device, and a suction detector are provided, and the descending speed of the vacuum cup is switched from high speed to low speed at the lower limit approach height, and the rising speed is changed from adsorbing the blank to the upper limit approach height. A blank suction device comprising a control means for outputting a control signal for switching to a high speed and a low speed at an upper limit approach height. 2. The lower approach height setter is formed by a distance detector mounted on the drive shaft that engages a blank held at a lower height to detect the actual distance to the blank. The blank suction device according to claim 1, characterized in that: