JPS6057961B2 - Unmanned automatic turning device with two headstocks - Google Patents

Description

[Detailed Description of the Invention] By providing two headstocks, the present invention can perform automatic turning of a workpiece by minimizing the non-machining time of the workpiece, and also improves machining accuracy. The present invention relates to an unmanned automatic turning device that can be achieved.

Conventionally, for the purpose of labor saving in machining such as turning of workpieces, numerical control lathes, workpiece feeders, and robot devices have been combined to perform workpiece mounting, turning, transfer of workpieces, and removal of processed products. A numerically controlled lathe system that performs all of the above is provided.

However, with this conventional numerically controlled lathe system, it is necessary to transfer the workpiece as described above and turn both ends of the workpiece separately before completing machining of the workpiece. system in advance 2
There are times when it is necessary to prepare a series, and there are many cases where manual intervention is unavoidable when transferring workpieces. Not only will the labor savings be incomplete, but also the need for a two-line system in terms of equipment will cause increased costs, including the expansion of equipment space, and will also reduce the accuracy of machining, such as hole machining. There are problems such as errors occurring between hole positions due to the transfer of the holes. Therefore, an object of the present invention is to significantly promote unmanned labor-saving in automatic turning of a workpiece as compared to the conventional numerically controlled lathe system described above, and to achieve cost reduction and improvement in machining accuracy in workpiece machining. Can unmanned automatic turning equipment? It is about providing.

In order to achieve this objective, according to the present invention, two workpiece turning headstocks facing each other on approximately one axis are provided so as to be able to approach and separate from each other, and the two headstocks are directed from the feed axis direction perpendicular to the one axis. In an unmanned automatic turning device that is provided with a turning section that can be fed and moved by the turning section, the turning section is constituted by two turning tables that are fed and driven independently, and each of the two turning tables is moved by the second turning section. By making it correspond to each of the two headstocks, it is possible to redundantly perform turning on the workpiece with each headstock, and also to remove the machined workpiece from one of the two headstocks and transfer it to the other headstock. A robot device is installed to attach the unprocessed workpiece,
When the machined workpiece is removed from one of the two headstocks by the robot device, the two headstocks approach each other to automatically transfer the workpiece between the two headstocks, and then An unmanned automatic turning device equipped with two headstocks is provided, characterized in that an unmachined workpiece is mounted on an empty headstock to continuously perform machining on both sides of the workpiece in the axial direction. It is.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 is a schematic plan view showing an example of an unmanned automatic turning device.

The device consists of two headstocks 1 that are arranged facing each other on one axis (Z-axis).
0a, 10b, and these headstocks 10a, 10b are each independently provided with respective feed mechanisms each having a Z-axis feed motor 12a, 12b, so that they move toward each other on the Z-axis and toward each other. It is now possible to move in the direction of separation. Further, both headstocks 10a and 10b are used for the workpiece. That is, the chuck devices 14a and 14b for holding the workpieces are respectively provided, and the workpieces Wl and W2 held by the chuck devices 14a and 14b can be rotated by a built-in main shaft motor (not shown). It is composed of one. On the other hand, a turning table 16 is provided which is movable in the x-axis direction perpendicular to the z-axis direction, which is the moving direction of the headstocks 10a and 10b, and the turning table 16 has a workpiece held on the headstock 10a side. A blade group 18a that performs turning on W1 and a blade group 18b that performs turning on workpiece W2 held on the headstock 10b side are provided. The turning table 16 is fed and moved to the headstocks 10a and 10b by a feed mechanism having an x-axis feed motor 20. Note that the feed motors 12a, 12b, 20 of the respective feed mechanisms in the Z-axis direction and the X-axis direction described above will be described below as being constituted by DC servo motors in the case of this embodiment. This device is also equipped on both sides with a well-known numerical control device 22 and a control unit device 24 in which a speed control unit, etc., which will be described later, is built-in, and on the other hand, a robot device 26 with well-known functions such as transporting and processing workpieces.
A workpiece feeder 28 for placing a large number of works W and sequentially feeding them to the turning section is also provided at the front part of the apparatus. Note that the work feeder 28 is a conventionally well-known device having a configuration for circulating a large number of works W on its upper surface, and the robot device 26 is a workpiece feeder 28.
The above unprocessed workpiece W is held, and the workpiece W is transported and loaded into, for example, the chuck device 14a of the headstock 10a (the loaded workpiece is shown as W1), and the chuck device of the headstock 10b is also loaded. 14b, the illustrated workpiece W2 is transferred to the workpiece feeder 28 again.
It has the function of sending it back to the top. The unmanned automatic turning apparatus configured by having the above-mentioned devices uses the group of cutters 18a on the turning table 16 to axially side the workpiece W1 on one headstock 10a. The same workpiece W1 is then moved to the position where the workpiece W2 is held in the headstock 10b by the approach movement of both headstocks 10a and 10b. After removing it, it is delivered and loaded, and then the group of cutters 18b on the turning table 16 performs the desired automatic turning on the opposite side of the same workpiece W1 in the axial direction under the command of the numerical control device 22. There are things that can be processed. In other words, the workpiece is transferred by moving one or both of the headstocks 10a, 10b in the Z-axis direction,
It is characterized by the ability to ultimately perform desired automatic turning on both sides of the workpiece in the axial direction to obtain a finished product, and in the following, based on this characteristic action, a large number of workpieces w will be continuously machined unattended. The machining cycle for automatic turning and the control system necessary for its execution will be explained below. Second
The figure is a graph showing a machining cycle performed by the unmanned automatic turning device shown in FIG. 2 shows a process of transporting two workpieces W1 and loading them onto the chuck device 14a of one headstock 10a.

If the workpiece W2 previously delivered from the headstock 10a is already loaded on the chuck device 14b of another headstock 10b while the process in this area "゛A" is progressing, the workpiece W2 In contrast, feed is given to the blade group 18b of the turning table 16 and the headstock 10b, and automatic turning is performed under the commands of the numerical control device 22. It shows an automatic turning process for workpiece W2. and area “4B’5
While the process of area "A'3" is progressing, the process of area "A'3" is completed and the workpiece W1 is waiting for the start of automatic turning on the headstock 10a. Area "C" is being machined by the process of area "B". This shows a process in which the completed workpiece W2 is removed from the chuck device 14b of the headstock 10b by the robot device 26 and returned to the workpiece feeder 28.At the same time as the play starts in the area 46C9, the area 46A99 is removed.
Feed is applied to the workpiece W1 loaded on the headstock 10a to the headstock 10a and the turning table 16, and automatic turning is started and progressed in the process of the area ゜゜D゛ by the cutter group 8a. Next, when the process in area "゜D" is completed and the turning process on one side of the workpiece W1 in the axial direction is completed, the workpiece W1 is moved from the headstock 10a to the headstock 10b which is already empty in the process in area ゜゜C゛. The process of the area "゜E゛" in which the information is exchanged is executed. That is, the workpiece W1 is transferred from the chuck device 14a of the headstock 10a to the chuck device 14b of the headstock 10b by the relative approach of the headstocks 10a and 10b.
At this time, the chuck device 14b of the headstock 10b holds one side in the axial direction of the workpiece W1 that has already been turned by the headstock 10a, so the posture of the workpiece W1 held by the chuck device 14b is tilted. This avoids the risk of causing errors in turning or misalignment of the subsequent workpiece W1. Headstock 10
When the workpiece W1 is delivered or transferred to b, the workpiece W1 is transferred again through the process in area "B".
Turning is performed on the opposite side of the shaft in the axial direction. FIG. 3 is a block diagram of a control system installed in the unmanned automatic turning machine shown in FIG. 1 to implement the above-mentioned machining cycle, and the same elements and devices as shown in FIG. 1 are the same. It is indicated by the reference number .

As is clear from the block diagram, in this control system, control signals are sent and received from the numerical controller 22 to the robot 26, and at the same time, the speed control unit 34 of the X-axis feed mechanism built in the control unit device 24, the headstock 10a or 10b
(7) Speed control unit 36 of the Z-axis direction feed mechanism, speed control unit 3 of the spindle motor of the headstock 10a or 10b
8. The control signal is configured to be sent and received to the Z-axis feed motor current control circuit 40 for setting the pressing force of the workpiece when transferring the workpiece W from the headstock 10a to the headstock 10b. In addition, the speed control unit 3 in the X-axis direction
4 is connected to the X-axis feed DC motor 20, and on the other hand, the Z-axis speed control unit 36 connects the Z-axis feed DC motor 12a of the headstock 10a or the headstock 10b (7) Z via a switching circuit 42. It is connected to the axial direction feeding DC motor 12b. Furthermore, the spindle motor speed control unit 38 controls the spindle motor 30 (
(not shown in Fig. 1) or the spindle motor 3 of the headstock 10b
2 (also not shown in FIG. 1). That is, the speed control unit 36 acts as a common speed control unit for the DC motors 12a, 12b by the action of the switching circuit 42, and similarly, the speed control unit 38 acts as a common speed control unit for the main shaft motors 30, 32 by the action of the switching circuit 44. The respective switching timings are designated by command signals from the numerical control device 22 in accordance with the machining cycle shown in FIG. 2 mentioned above. In the control system shown in FIG. 3, each speed control unit 34, 36, 38, etc. may be configured using a servo amplifier unit used in a conventional numerically controlled machine tool. In addition, the z-axis feed motor current control circuit 40 for setting the pressing force of the workpiece is connected to the headstock 1.
For example, when transferring the workpiece W from the headstock 10a to the headstock 10b, the DC motor 12 in the Z-axis feeding direction
The output of the DC mofuta 12a is controlled by controlling the field current of a, and the transfer force is adjusted according to the dimensions, size, weight, etc. of the workpiece W. As a result, the transfer force of the workpiece W is controlled.
is accurately gripped by a chuck device 14b (see FIG. 1) on the headstock 10b side to improve the accuracy of the subsequent turning process. FIG. 4 shows an embodiment of the current control circuit for the Z-axis feed motor, in which a voltage signal indicating the amount of current of the feed DC motor 12a sent from the speed control unit 36 in the Z-axis direction is connected to the terminal 48. has been entered. The current set by the volume 58 is supplied to the Z-axis feeding DC motor 12a via the operational amplifier 60 until the voltage input reaches the voltage value set by the volumes 54 and 56. ing. Note that the voltage signal input to the input terminal 48 and the volume 54
Comparison with the voltage values set by and 56 is performed by comparator circuits 50 and 52. In addition, a configuration is adopted in which a manual signal is inputted from the input terminal 64 to the OR circuit 62, so that it is possible to select whether the current control circuit is enabled or disabled, and when the current control circuit is enabled, the headstock 10a ( 7) Since it is necessary to break the position control loop in the Z-axis direction, a configuration is adopted in which the position error signal input to the input terminal 66 is invalidated by the analog switch 68. FIG. 5 is a circuit diagram showing a specific embodiment of the switching circuit 42 or 44 shown in FIG. Or when the A2S signal comes out,
The contacts of the relay 74 or 76 are switched, thereby switching the output of the speed control unit 36 or 38 (Fig. 3) to either the feed DC motor 12a or 12b (Fig. 3), or the main shaft motor. 30 or 32 (FIG. 3).

In addition, the times shown in the upper row of Figure 5. on the road, 78,80
is the output terminal of the speed control unit 36 or 38, 82, 8
4 is a switching contact of the relays 74 and 76, 86 and 88 are output terminals of one of the outputs of the speed control unit 36 or 38, and 90
, 92 are the other output terminals. As is clear from the above explanation, according to the unmanned automatic turning equipment shown in Figs. This makes it possible to perform continuous, unmanned turning on both sides of the workpiece, and furthermore, it becomes possible to continuously and automatically turn a large number of workpieces using a robot device and a work feeder.

In particular, the workpiece transfer action between the headstocks not only minimizes the non-machining time in the machining process, but also significantly improves the workpiece gripping accuracy with the chuck devices on both headstocks, resulting in improved turning accuracy. It also leads to improvement. In addition, in order to perform machining on both sides of a workpiece in the axial direction using a conventional numerically controlled lathe system, a two-line system is required, which tends to cause an expansion of the machining space at the machining site. In this embodiment, it is not necessary to secure a large machining space, and it is possible to inevitably reduce the machining cost. In the examples shown in FIGS. 1 to 5, since a single turning table 16 is provided, both workpieces W can be machined at the same time even when the workpieces W are loaded on both the headstocks 10a and 10b. However, an embodiment of the present invention that improves this and makes simultaneous machining possible will be described below with reference to FIGS. 6 to 8.

In the embodiment shown in FIGS. 6 to 8, the same elements as those in the previous embodiment are designated by the same reference numerals. Now, referring to Figure 6,
This embodiment differs from the previous embodiment in that two turning tables 16a and 1 are used instead of the turning table 16 in the previous example.
6b is provided, and the turning table 16a is connected to the X-axis direction feed motor 2.
0a allows forward movement in the X-axis direction relative to the headstock 10a, while the turning table 16b is moved by the x-axis direction feed motor 2.
0b, it is configured to be able to feed and move in the x-axis direction relative to the headstock 10b.

Since the feed movement of both turning tables 16a and 16b is independently controlled by the numerical control device 22,
The turning table 16a is rotated by the headstock 10a by its cutter group 18a.
At the same time that the turning table 16b is turning the workpiece W1 on the headstock 10b, the turning table 16b can turn the workpiece W2 on the headstock 10b using its blade group 18b. As a result, according to this embodiment, it is possible to achieve the effect that the machining process for each workpiece W can be carried out more efficiently. FIG. 7 is a block diagram of the control system in this embodiment.

As is clear from comparing the block diagram of FIG. 7 with the block diagram of the control system of the previous embodiment shown in FIG. 3, no switching circuit means is used in this embodiment. In other words, the DC servo motor 20 for feeding in the X-axis direction
a, 20B, . DC servo motor 12 for feeding in the Z-axis direction
a, 12b1 Each spindle motor 30 of the headstock 10a, 10b
, 32 are each independently controlled by the numerical control device 22. Therefore, speed control units for each of the motors are provided independently. That is, for the motor 20a, the speed control unit 34
For the a1 motor 20b, the speed control unit 34b1
For the motor 12a, a speed control unit 36a1 For the motor 12b, a speed control unit 36b1 For the main shaft motor 30, a speed control unit 38a1 For the main shaft motor 3
2, a speed control unit 38b is inserted between each numerical control device 22. and headstock 10
A current control circuit 40 that sets the workpiece pressing force when transferring the workpiece W from a to the headstock 10b is provided to control the current of the feeding DC servo motor 12a in the Z-axis direction. Further, the robot device 26 is connected to the numerical control device 22.
Needless to say, it is provided to carry out various functions such as transporting, mounting, and removing workpieces under the instructions of the following. Next, the machining cycle of this embodiment will be explained with reference to the graph of FIG. 8 and FIG. 6.

Area '4 in the graph of the machining cycle shown in Figure 8
N2 is a process in which the robot device 26 transports the work w from the work feeder 28 to the chuck device 14a of the headstock 10a and loads it as the work W1.

While the process of this area '6A'2 is progressing, the headstock 1 has already been removed.
Work W2 transferred from the headstock 10a to 0b
is loaded, the headstock 10b and the turning table 16b
By this feeding, the group of blades 18b performs a desired automatic turning process on one side of the workpiece W2 in the axial direction. region"'
B' shows the turning process of this workpiece W2. On the other hand, when the process indicated by the area “゜A゛” is completed, the area “゜”
Workpiece W1 loaded on the headstock 10a as shown by C
On the other hand, automatic turning is performed on one side of the workpiece W1 in the axial direction by the blade group 18a by feeding the headstock 10a and the turning table 16a. Then, since the automatic turning process of the workpiece W2 that has been carried out in this area ゜゛B゛ is completed, at the end of the process, the workpiece that has been machined from the headstock 10b by the robot device 26 in the process shown in the area ゛D゛. W2 is removed and returned to the workpiece feeder 28.As a result, the chuck device 14b of the headstock 10b becomes empty.When the printing in area 64D99 progresses, the process in area 6°C99 progresses in parallel. Therefore, when the chuck device 14 becomes empty, the automatic turning process for one side of the workpiece W1 loaded on the headstock 10a in the axial direction is completed.
As a characteristic operation process of the present invention, the headstock 1
0a and 10b are relatively close to each other in the Z-axis direction and the workpiece W1
is moved from the headstock 10a to the headstock 10b. When transferring the workpiece W1, one side of the workpiece W1, which has already been automatically turned, is gripped by the chuck device 14b of the headstock 10b, so the workpiece W1 can be transferred accurately without tilting or shifting. This means that it can be maintained. When the process in area "E" is completed, automatic turning is performed again on the opposite side of the workpiece W1 in the axial direction by the process in area "B". The chuck device 14a of the headstock 10a, which became empty upon completion of the process, is again loaded with a new workpiece W in the process of area ゜゜A゛. As is clear from the two embodiments of the present invention described above, according to the present invention, two headstocks are provided, and these two headstocks move toward and away from each other approximately on one axis. Therefore, the transfer of the workpiece is achieved automatically and unmanned, and accurate gripping of the workpiece is ensured, so that the efficiency of the unmanned automatic turning process and the accuracy of the turning process are improved.

Furthermore, since the scale of processing equipment for processing both sides of the workpiece in the axial direction is kept to a minimum, an effect of reducing processing costs can also be obtained.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an embodiment of an unmanned automatic turning machine equipped with two headstocks, Fig. 2 is a graph explaining a machining cycle according to the embodiment, and Fig. 3 is a control of the embodiment. 4 is a circuit diagram showing an embodiment of the motor current control circuit in the control system, FIG. 5 is a circuit diagram showing an embodiment of the switching circuit, and FIG. 6 is a circuit diagram showing an embodiment of the motor current control circuit in the control system. FIG. 7 is a block diagram of the control system of the embodiment, and FIG. 8 is a graph diagram explaining the machining cycle of the embodiment. 10a, 10b...headstock, 12a, 12b...Z
DC servo motor for axial feed, 14a, 14b...
・Chuck device, 16, 16a, 16b...turning table,
18a, 18b... cutlery group, 20, 20a, 20b...
...DC servo motor for feeding in the X-axis direction, 22... Numerical control device, 26... Funeral pot device, 28... Work feeder.

Claims (1)

[Claims] 1. Two workpiece turning headstocks facing each other on a substantially uniaxial line are provided so as to be able to approach and separate from each other, and a turning section is provided that can feed and move toward the two headstocks from a feed axis direction perpendicular to the uniaxial line. In unmanned automatic turning equipment,
The turning processing section is constituted by two turning tables which are fed and driven independently, and each of the two turning tables is connected to the two turning tables.
By making it correspond to each of the two headstocks, it is possible to redundantly perform the turning of the workpiece on each headstock, and the above-mentioned two
A robot device is provided that removes a machined workpiece from one of the two headstocks and attaches an unprocessed workpiece to the other headstock, and the machined workpiece is removed from one of the two headstocks by the robot device. When the workpiece is removed, the two headstocks approach each other to automatically transfer the workpiece between the two headstocks, and then an unprocessed workpiece is attached to the empty headstock so that both sides of the workpiece in the axial direction are transferred. An unmanned automatic turning device equipped with two headstocks, characterized in that machining can be performed continuously.