JPH05250021A - Tool exchange device - Google Patents

Abstract

PURPOSE:To eliminate the measurement of a central position of a tool to be exchanged by inputting the output of an ITV fitted to a spindle to a coordinate detector, calculating deviation between the central position of a tool end face image in a picked-up picture and the central point of image pickup by the coordinate detector, and moving the spindle to a coordinate position corresponding to the amount of deviation. CONSTITUTION:This device is provided with an ITV 12 mounted on a spindle 1 so as to form the end face images of a tool post 5 and the tool for exchange on an image pickup plane, coordinate detector 14 to input the output of the ITV 12, and NC device 15 to move the spindle 1 to the coordinate position based on the amount of deviation calculated by the coordinate detector 14 and to exchange a used tool 4 with the tool for exchange.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool changing device using an ITV (industrial television camera) and a coordinate detecting device.

[0002]

2. Description of the Related Art For example, in a drilling device for a printed wiring board, when a tool such as a drill is worn or damaged,
A device for changing tools is attached. The replacement tool is arranged near the machining table within the movable range of the machining spindle. If the tool wear reaches the limit that can be machined or if it breaks and becomes unusable, move the spindle to a place where no tool is installed and eject the unusable tool.

Next, the structure of a conventional tool changing device will be described with reference to FIG. In FIG. 5, 1 is a spindle, 2 is a chuck, 3 is a collar, 4 is a tool, 5 to 7 are tool posts, and 8 is a tool post.
Is a tool table, and 9 is a processing table. The main shaft 1 is moved in the X-axis and Z-axis directions by a main shaft moving motor (not shown). The tool 4 is held by the chuck 2 of the spindle 1. A tool table 8 on which a replacement tool is arranged is connected to the processing table 9. The processing table 9 is moved along with the tool base 8 in the Y-axis direction by a motor (not shown).

Next, the side view of FIG. 5 will be described with reference to FIG. The replacement tool 10 is held by the tool post 6 on the tool rest 8 via the collar 3 through which the tool passes. The position A is the center position of the empty tool post 5 on which the replacement tool 10 is not mounted, and the position B is the center position of the replacement tool 10.

Next, the operation when the wear of the tool 4 reaches the machining limit and the tool 4 is replaced with the replacement tool 10 will be described by the following procedure AC. A Move spindle 1 over position A. B. Collar 3 lowers spindle 1 to the position of tool post 5. (C) The chuck 2 of the spindle 1 is opened and the tool 4 is released from the spindle 1. D. Raise spindle 1. E Move spindle 1 to position B. (F) Lower the spindle 1 to a position where the replacement tool 10 can be held. Close the chuck 2 of the main shaft 1 and replace the main shaft 1 with the replacement tool 1
Grab 0. KU Raise spindle 1. From the above operation, the position A and the position B must be accurately measured in advance in order to reliably replace the tool.

Therefore, it is necessary to accurately measure the positions A and B, and the center positions of other tool posts when assembling and adjusting the apparatus. Also, similar measurement is required when the tool base 8 is replaced for maintenance or the like. Further, recently, a tool to be used for each type of printed wiring board to be processed is previously mounted on the tool base 8, and the tool base 8 may be replaced every time the type of printed wiring board changes. In this case, measuring the position A and the position B every time the tool base 8 is replaced is problematic in efficiency. Therefore, a tool base 8 in which the center positions of the tool posts 5 to 7 are accurately machined is required, and a mechanism for mounting the tool base 8 on the machining table 9 is also required to be highly accurate.

[0007]

According to the present invention, the ITV is attached to the spindle 1 of FIG. 5, the output of the ITV is input to the coordinate detecting device, and the coordinate detecting device captures the center position and the image of the tool end face image in the image pickup screen. An object of the present invention is to provide a tool changing device which eliminates the measurement of the center position of a tool to be replaced by finding the deviations ΔX and ΔY of the center points and moving the spindle 1 to a coordinate position according to the deviation amount.

[0008]

To achieve this object, according to the present invention, a distance L from the center of the main shaft 1 in the Y-axis direction is used.
A lens 11 having a focal length longer than that of the tip of the used tool 4,
The ITV 12 for forming the end surface images of the tool post 5 and the replacement tool 10 on the imaging surface, and the output of the ITV 12 are input,
The coordinate detection device 14 for obtaining the deviations ΔX25 and ΔY24 between the center position 26 of the tool end surface image and the imaging center point 23 in the image pickup screen 21, the deviation amount obtained by the coordinate detection device 14, and the spindle 1 and I.
The NC device 15 is provided which moves the spindle 1 to a coordinate position obtained by adding the distance L of the TV 12 and replaces the used tool 4 with the replacement tool 10.

[0009]

Next, the construction of the tool changing mechanism according to the present invention will be described with reference to FIG. In FIG. 1, 11 is a lens and 12 is IT
V and 13 are codes, 14 is a coordinate detection device, 15 is an NC device, and others are the same as those in FIG. The ITV 12 is attached to the main shaft 1 such that the center of the ITV 12 is located at a distance L from the center of the main shaft 1 in the Y-axis direction.

The spindle 1 and the ITV 12 are connected, and the ITV 12 also moves as the spindle 1 moves. ITV12
The lens 11 is attached to the lens and has a focal length longer than that of the tip of the tool 4. Therefore, by selecting the height of the main axis, the end surface images of the tool post 5 and the replacement tool 10 can be formed on the image pickup surface of the ITV 12. ITV
Reference numeral 12 is connected to the coordinate detecting device 14 via the cord 13, and the output of the coordinate detecting device 14 is connected to the NC device 15.

Next, the image pickup screen of the coordinate detecting device 14 is shown in FIG.
Will be explained. The coordinate detecting device 14 detects the deviation Δ between the center position 26 of the tool end surface image and the imaging center point 23 in the imaging screen 21.
It is assumed that X25 and ΔY24 can be obtained. N
The C device 15 moves the spindle 1 to the coordinate position obtained by adding the displacement amount obtained by the coordinate detection device 14 and the distance L between the spindle 1 and the ITV 12, and replaces the tool 4 with the replacement tool 10.

Although the processing method of the coordinate detecting device 14 will be described later, the deviations ΔX25 and ΔY2 between the center position 26 of the end face image 22 of the replacement tool and the image pickup center point 23 in the image pickup screen 21 of FIG.
4 can be obtained in pixel units. Therefore, if the image pickup size per pixel is clear, the shifts ΔX25 and ΔY24 can be calculated as the physical shift amount by the following formula.

The displacement amount x in the X direction is x (mm) = ΔX (pixels) × α (mm / pixel) The displacement amount y in the Y direction is y (mm) = ΔY (pixels) × β (mm / pixel) , Α is the image pickup size of 1 pixel in the X direction β is the image pickup size of 1 pixel in the Y direction

Further, the ITV 12 and the spindle 1 are separated by a distance L in the Y-axis direction, and the movement amounts Lx and Ly for moving the spindle 1 from the current value to the tool center position determined by the coordinate detecting device 14 are as follows. It can be calculated by the formula. Lx = x (mm) Ly = L (mm) + y (mm)

Next, a method for obtaining the center point of the image picked up by the coordinate detecting device 14 will be described with reference to FIGS. ITV
12 is the clock signal 2 generated by the oscillation circuit 216.
The vertical synchronizing signal 200 and the horizontal synchronizing signal 201 generated based on 04 are supplied. The ITV 12 outputs the video signal 202 in synchronization with this synchronization signal. The video signal 202 is sliced by the binarization circuit 207 at the waveform slice level Tth to obtain a binary image signal 203.

FIG. 3 shows a circuit for obtaining the coordinates Xa, Xb and Xc in the X direction, and FIG. 4 shows the coordinates Ya, Yb in the Y direction.
And a circuit for obtaining Yc. The binary image signal 203 in FIG. 3 is a flip-flop (hereinafter referred to as FF) 20.
8 and the gate 212, the output 204 of the FF208
Is connected to the inverter 209 and the gate 212. The output of the inverter 209 is the clock signal 20 at the gate 210.
4 and the horizontal synchronizing signal 201 are ANDed and the counter 2
It has 11 count pulse signals. Therefore,
The counter 211 has the FF reset,
Moreover, when the horizontal synchronizing signal 201 is active, the clock pulse 204 is counted.

The output signal of the counter 211 is the data bus 2
It is connected to the CPU 214 via 40. CPU2
14 can always know the value of the counter 211. The gate 212 obtains the logical product of the output 204 of the FF 208, the binary image signal 203 and the clock signal 204.

The output of the gate 212 becomes the count pulse signal of the counter 213. Therefore, the counter 213
Counts clock pulses 204 only when FF 208 is set and binary image signal 203 is active. The output signal of the counter 213 is the data bus 2
It is connected to the CPU 214 via 40. CPU 214
Can always know the value of the counter 213.

Now, consider the operation when the scanning line n250 crosses over the end surface image 22 of the replacement tool 4 on the imaging screen 21. At time ta, the FF 208 is reset and the horizontal sync signal 201 becomes active. Therefore, the counter 211 starts counting clock pulses.

When the binary image signal becomes active at time tb, the FF 208 is set. Therefore, the counter 211 stops the counter. Since the value of the counter 211 is the number of clocks = the number of pixels, it means that the position Xa in FIG. 2 is obtained by the number of clocks. On the other hand, the counter 213 starts counting the clock 204. When the binary image signal is disabled at time tc, the counter 213
Stops counting. The counter 213 is Xb in FIG.
This means that the value of −Xa is obtained by the number of clocks.

The CPU 214 has variables N and M,
The initial value is N = M = 0. When the horizontal synchronizing signal 201 is disabled, the CPU 214 will use the counter 2
The value of 13 is read and the value is set as Nxb. The value of the previous counter 213 is set to N, Nxb and N are compared, and the larger value is newly stored as N. At this time, Nx
If the b value is larger than N, the value of the counter 211 is read and stored as M. When this is operated on the entire imaging screen 21, the variable N of the CPU 214 becomes the value of Xb-Xa in FIG. 2 as a final result. Further, the variable M becomes the Xa value in FIG. Therefore, Xc in FIG. 2 can be calculated by the following formula. Xc = (N / 2) + M (pixel)

Next, a method for obtaining Ya, Yb and Yc in FIG. 2 will be described with reference to FIG. The binary image signal 203 in FIG.
It is connected to the gate 220 and the gate 227. Gate 22
0 is logically ANDed with the vertical synchronizing signal 200 and is connected to the set input of the FF 221. Therefore, the FF 221 is set when the binary image signal becomes active while the vertical synchronizing signal is active.

The output 222 of the FF 221 is the inverter 22.
3 and gate 227. The output of the inverter 223 is logically ANDed with the logical negation signal of the horizontal synchronizing signal 201 at the gate 224 and becomes a count pulse signal of the counter 226. Therefore, the counter 226 is
When 221 is reset, the number of pulses of the horizontal synchronizing signal 201 is counted. The output signal of the counter 226 is connected to the CPU 214 via the data bus 240.

The CPU 214 can know the value of the counter 226 at any time. The gate 227 obtains the logical product of the output 222 of the FF 221 and the binary image signal 203. The output of the gate 227 becomes the count pulse signal of the counter 228. Therefore, the counter 228 counts the pulses of the binary image signal 203 only when the FF 221 is set and the binary image signal 203 is active.

The output signal of the counter 228 is the data bus 2
It is connected to the CPU 214 via 40. CPU 214
Can always know the value of the counter 228. When this is operated until the vertical synchronization signal is disabled, the counter 226 has obtained Ya in FIG. 2 and the counter 228 has obtained Yb-Ya in scanning line units. Therefore, Yc can be calculated by the following equation.

Yc = (value of counter 228/2) + value of counter 226 From the above results, ΔX and ΔY are obtained by the following equations. ΔX = Xd−Xc ΔY = Yd−Yc

According to the present invention, when the wear of the tool reaches the working limit and the tool is replaced, the procedure of the following ke-ni is performed. Move the ITV12 to position A. The ITV 12 is lowered to a position where the end face image of the co-tool post 5 is formed on the image pickup surface of the ITV 12. The coordinate detecting device 14 obtains the deviations ΔX25 and ΔY24 between the center coordinates of the tool post 5 and the center point 23 of the ITV. Shift amount determined by coordinate detection device 14, spindle 1 and ITV
The spindle 1 is moved to the coordinate position obtained by adding the distance L of 12. The spindle 1 is lowered to a position where the collar 3 is held by the tool post 5. The chuck 2 of the main spindle 1 is opened, and the tool 4 is released from the main spindle. So the spindle 1 is lifted. Move ITV12 above position B. H. The ITV 12 is lowered to a position where the end surface image of the exchange tool 10 is imaged on the ITV imaging surface. By the coordinate detecting device 14, deviations ΔX25 and ΔY24 between the center coordinates of the replacement tool 10 and the center point 23 of the ITV 12 are detected.
Ask for. The amount of deviation obtained by the coordinate detection device 14, the spindle 1 and the ITV
The spindle 1 is moved to the coordinate position obtained by adding the distance L of 12. G Lower the spindle 1 to a position where the replacement tool 10 can be held. 1 Close the chuck 2 of the spindle 1 and replace the spindle 1 with the replacement tool 1
Grab 0. D Ascend the spindle 1.

[0028]

According to the present invention, the ITV is attached to the spindle 1, the output of the ITV is input to the coordinate detecting device, and the coordinate detecting device shifts the deviation ΔX between the center position of the tool end face image in the image pickup screen and the image pickup center point. And ΔY are obtained, and the spindle 1 is moved to the coordinate position corresponding to the amount of deviation, so that the measurement of the center position of the tool to be replaced can be eliminated.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a tool changing device according to the present invention.

FIG. 2 is an image view of a tool end surface in an image pickup screen of a coordinate detection device.

FIG. 3 is an explanatory diagram for obtaining coordinates Xa, Xb, and Xc in the X direction of the image captured by the coordinate detection device.

FIG. 4 is an explanatory diagram for obtaining Y-direction coordinates Ya, Yb, and Yc of an image captured by the coordinate detection device.

FIG. 5 is a configuration diagram of a tool changing device according to a conventional technique.

FIG. 6 is a side view of FIG.

[Explanation of symbols]

 1 Spindle 2 Chuck 3 Color 4 Tool 5-7 Tool Post 8 Tool Table 9 Processing Table 10 Replacement Tool 11 Lens 12 ITV 13 Code 14 Coordinate Detection Device 15 NC Device

Claims (1)

[Claims] 1. A lens (11) mounted at a position separated from the center of the main shaft (1) in the Y-axis direction by a distance L and having a focal length longer than the tip of a used tool (4). ,
The ITV (12) that forms the end surface image of the tool post (5) and the replacement tool (10) on the imaging surface and the output of the ITV (12) are input, and the tool end surface image in the imaging screen (21) is displayed. The coordinate detection device (14) that obtains the deviations ΔX (25) and ΔY (24) between the center position (26) and the imaging center point (23), the deviation amount obtained by the coordinate detection device (14), and the spindle (1). ITV (1
Move the spindle (1) to the coordinate position obtained by adding the distance L of 2) and replace the used tool (4) with the replacement tool (10) N
A tool changer comprising a C device (15).