JPH0224599Y2 - - Google Patents

Description

[Detailed description of the invention] a. Industrial application field This invention relates to an automatic indexing device for a tool post in a machine tool.

b. Prior Art Conventionally, absolute position detection methods have been used for automatic indexing of machine tool turrets, but this method requires special sensors such as rotary switches, absolute encoders, or multiple A sensor was needed. To change the position of the tool on a machine tool's rotating tool post, change the tool post from 1/4 to 1/8 depending on the number of tools.
Since the rotation is performed by rotating one rotation at a time, if you somehow memorize the tool number during machining, you will not need to use the complicated absolute position detection method used in the past to index the rotating tool post. good.

C Problems to be solved by the invention As mentioned above, the indexing of the conventional rotating tool post is
Since it relied on an absolute position detection method, it required a special sensor or a large number of sensors, which caused problems in terms of cost and reliability. This invention solves the above problems by using a small number of simple sensors (for example, a proximity sensor) that detect the position of the rotating tool post and an N-digit ring counter that stores N tool numbers.
The object of the present invention is to provide an automatic indexing device for a tool post that is inexpensive and highly reliable.

d. Means for solving the problem In order to achieve the above object, this invention uses a motor for rotating the rotating tool post and a motor for rotating the rotating tool post, and the number of index positions provided on the rotating tool post by one rotation of the rotating tool post. A rotating shaft that rotates by an integral multiple of N, a first sensor that detects the rotation of the rotating shaft every rotation, a counter that counts the detection signal of the first sensor, and a count value of the counter and a preset command value. a second sensor for detecting the origin position of the rotating tool post; and a second sensor for detecting the origin position of the rotating tool post; The apparatus includes a mismatch circuit that compares whether or not a signal corresponding to the origin position matches the detection signal of the second sensor, and displays an abnormality on a display when they do not match.

e Effect Since it is configured in this way, the indexing member rotates 1/N with one rotation of the prime mover, and the N of the prime mover rotates by 1/N.
The rotation causes the tool number position of the rotating tool post to return to its original position. When the prime mover rotates, the first sensor outputs one pulse per rotation of the prime mover, causing the blade position to shift by one position. These pulses are counted by a ring counter, and the output signal thereof is sent to a matching circuit where it is compared with a command value that predetermines the position of the tool number on the tool rest. When the two signals match, a stop signal is output to stop the motive vehicle, the indexing member stops as the motive vehicle stops, and the turret is fixed at this position. Ring counter is N
In the digit, only one flip-flop is at logic 1 and is cycled by the pulse of the first sensor.

In addition, with the above configuration, the detection signal of the second sensor that detects the origin position of the swivel tool post is compared with whether or not the data of the counter corresponds to the origin position of the swivel tool post, and if they do not match, an indication is displayed by the mismatch circuit. This is to display an abnormality on the device.

f Example Next, an example of this invention will be described with reference to the drawings. Figure 4 is an overall diagram showing the positional relationship of this invention installed on an NC-controlled (not shown) turret lathe. The turret lathe 1 consists of main parts such as a headstock 3, a chuck 5, a bed 7, a carriage 9, a cross feed table 11, and a swivel turret 13.
3, the automatic tool post indexing device 15 of this invention is attached.

Details of the automatic tool rest indexing device 15 are shown in FIG. An indexing member (for example, a driven wheel of a 1/6 turn geneva stop) 19 is provided on the shaft 17 of a rotating tool rest 13 equipped with N blades, for example, 6 blades, and is engaged with the indexing member 19 to lock it. A motor vehicle 21 of a Geneva stop is connected to a turret rotation motor 27 via a shaft 23 and a reduction gear 25. At the right end of the shaft 23 of the Geneva motor vehicle 21, there is a tool post indexing plate 2.
9 is provided, and a first sensor (for example, a proximity switch) 31 is provided adjacent to the index plate 29 to detect this position. Further, at the right end of the shaft 17 of the rotating tool post 13, the tool post origin position (for example, the first
A detection plate 33 is provided for detecting the position of the blade, and a second sensor (for example, a proximity switch) 35 for detecting this position is provided adjacent to the detection plate 33. Further, a turret fixing pin 37 for fixing the rotating turret 13 during cutting work is provided on the cylinder 39, and a pin retraction confirmation sensor 41 is further provided on the cylinder.

A block diagram of the control circuit of this automatic tool post indexing device is shown in FIG. The turret rotation command signal and the detection signal of the first sensor 31 are transmitted through the AND gate 43.
N-digit (for example, 6-digit) ring counter 4
5, the counted value is sent to the matching circuit 47, where it is compared with a preset knife number command value from the NC device, and its output signal is sent to the AND gate 49. A turret rotation command signal is input to the AND gate 49, and its output signal (H level) serves as a stop signal for the turret rotation motor 27 (see FIG. 1). Moreover, the count value of the ring counter 45 is
It is decoded by the decoder 51 and input to the discrepancy circuit 53 together with the detection signal of the second sensor 35, and the output signal (H level) is displayed on a display (not shown) indicating the operating status (normal, abnormal) of this device. Display.

Next, the operation of this device will be explained with reference to the flowchart shown in FIG. The turret fixing pin 37 is removed by the turret rotation command (step A), and after confirming the signal from the pin retraction confirmation sensor 41,
Start the swing motor 27. The rotation of the swing motor 27 is transmitted to the speed reducer 25, the shaft 23, the prime mover 21, the indexing member 19, the shaft 17, and the swing turret 13 in this order (Step B).

As the driving shaft 23 rotates, a pulse signal is sent from the first sensor 31 to the AND gate 43 once per rotation, and the output signal is input to the ring counter 45 by AND with the turret rotation command signal. (Steps C and D).

If there is a pulse from the second sensor 35 that detects the origin position of the rotating tool post (for example, the position of the first tool) while the ring counter is counting pulses, this pulse is input to the discrepancy circuit 53. Further, a signal obtained by decoding ring counter data (a signal corresponding to the origin position of the tool post, for example, the first tool position) by the decoder 51 is also input to the mismatch circuit 53. If the two signals do not match, the output signal (H level) indicates an abnormality on the display that displays the operating state of this device. If both signals match and if there is no signal of the second sensor to the mismatch circuit, the respective signals enter the match circuit 47 of step G (steps E, F).

The signal entering the matching circuit 47 is
It is compared with the blade number command value from the NC device, and if they match, the output is sent to the AND gate 49.
If they do not match, the signal is returned to step E (step G). Since the AND gate 49 contains the turret rotation command signal, the AND gate 49 outputs a signal to stop the turret rotation motor 27 based on this and the output signal of the matching circuit 47. After the swing motor is stopped, the swing tool rest is fixed by the tool rest fixing pin 37, and the tool rest indexing operation is completed (steps H and I).

In this way, even if we add a sensor for confirmation, we only need two simple sensors and N digits (6 in the example).
By using a ring counter (memory is non-volatile, for example), it is possible to accurately automatically index a rotating tool rest to which N (in the embodiment, six) blades are attached.

g. Effects As understood from the explanation of the embodiments above, the present invention can be summarized as follows. A rotating shaft 23 that rotates by an integral multiple of the number of indexed positions N, and a rotating shaft 2
The first sensor 31 detects the rotation of No. 3 every rotation.
, a counter 45 that counts the detection signal of the first sensor 31, and a matching circuit 47 that outputs a stop signal for the motor 27 when the counted value of the counter 45 matches a preset command value. The automatic indexing device includes a second sensor 35 that detects the origin position of the rotating tool post 13, and a second sensor 35 that detects the origin position of the rotating tool post 13 when the signal from the counter 45 is a signal corresponding to the origin position of the rotating tool post 13. It is provided with a mismatch circuit 53 that compares whether or not it matches the detection signal and displays an abnormality on a display when there is a mismatch.

With the above configuration, in the present invention, when the preset command value and the count value of the counter 45 match, the motor 27 is stopped and the rotation of the rotating tool post 13 is stopped. In the invention, the signal of the second sensor 35 that detects the origin position of the swivel tool post 13 is compared with the data of the counter 45 to see if it corresponds to the origin position of the swivel tool post 13, and if they do not match, the mismatch circuit 53 According to
Since the abnormality is displayed on the display, the presence or absence of the abnormality can be detected every rotation of the rotating tool post 13. Therefore, for example, even if an abnormality (for example, failure) occurs in one or both of the first and second sensors 31, 35, it can be detected as an abnormal state.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of this invention, FIG. 2 is a block diagram of the control circuit, FIG. 3 is a control flowchart of the tool post, and FIG. 4 is an overall diagram of a turret lathe using this invention. Explanation of the symbols representing the main parts of the drawing, 1...
Turret lathe, 13... Swivel turret, 15... Turret indexing device, 19... Indexing member, 21... Drive wheel, 27... Turret rotating motor, 29... Index plate, 31... First sensor, 33...Detection plate, 35
...Second sensor, 43...And gate, 45...
...Ring counter, 47... Matching circuit, 49...
AND gate, 51... decoder, 53... mismatch circuit.

Claims (1)

[Scope of utility model registration request] Motor 27 for rotating the rotating tool post 13
, a rotating shaft 23 that rotates by an integral multiple of the number N of indexing positions provided in the rotating tool post 13 by one rotation of the rotating tool post 13, and a first sensor 31 that detects the rotation of the rotating shaft 23 every rotation. , a counter 45 that counts the detection signal of the first sensor 31, and a counter 45.
The origin position of the rotating tool post 13 is detected by an automatic indexing device for the tool post, which is equipped with a matching circuit 47 that outputs a stop signal for the motor 27 when the counted value of the above matches a preset command value. A comparison is made between the second sensor 35 and the detection signal of the second sensor 35 to see if the signal from the counter 45 matches the detection signal of the second sensor 35 when the signal corresponds to the origin position of the rotating tool post 13. An automatic indexing device for a tool post, comprising: a discrepancy circuit 53 for displaying an abnormality.