JP7737473B2 - Multi-tasking machine - Google Patents

Description

The present invention relates to a multi-tasking machine that efficiently and appropriately changes tools using an automatic tool changer.

Machine tools use automatic tool changers that store multiple tools and automatically change tools as needed. Patent Document 1 below discloses an automatic tool changer that has a tool magazine that stores multiple tools and is attached to a turret, and uses a tool change mechanism to exchange the tool attached to the turret for a tool stored in the tool magazine. The time required for tool changes is reduced by preparing the next tool to be used on the tool post while machining is being performed with the tool on the tool post, and by preparing the next tool to be used on the tool spindle while machining is being performed with the tool on the tool post.

Japanese Patent Application Laid-Open No. 2005-125483

However, changing tools during machining using the conventional machine tools described above poses a problem. When machining a workpiece using the machine tools described above, chips from the workpiece and coolant used for cooling purposes are scattered around while the tool on the turret is being used for machining. When changing tools in a machining chamber in such an environment, the scattered chips can get into the tool mounting section of the tool spindle, preventing the tool from being properly mounted and reducing machining accuracy. On the other hand, changing tools after machining on the turret is complete increases the cycle time, reducing machining efficiency.

Therefore, in order to solve this problem, the present invention aims to provide a multi-tasking machine that performs appropriate tool changes while shortening machining time.

A multi-tasking machine according to one aspect of the present invention comprises a work spindle unit that imparts rotation to a workpiece gripped by a chuck mechanism, a turret unit that performs machining on the workpiece gripped by the work spindle unit using a turret tool that is swivel-indexed from among a plurality of turret tools, a tool spindle unit that performs machining on the workpiece gripped by the work spindle unit by rotating an exchangeable spindle head tool, an automatic tool changer that exchanges the spindle head tool with respect to the tool spindle unit, an openable and closable separation shutter provided between the turret unit and the tool spindle unit, and a control device that controls the driving of each of the devices and the separation shutter, and the control device controls the driving of the workpiece gripped by the work spindle unit. In a machining process in which continuous machining is performed by the turret device and the tool spindle device, if the separation shutter is closed, the automatic tool changer is caused to change the spindle head tool of the tool spindle device in parallel with the machining of the workpiece by the turret device . In this case, if it is confirmed that the separation shutter is closed according to the detection result of the open/closed state of the separation shutter, the spindle head tool is changed in parallel with the machining of the workpiece by the turret device, and if it is not confirmed that the separation shutter is closed, the spindle head tool is made to wait at a position just before the change, and the spindle head tool is changed after the machining of the workpiece by the turret device is completed .

According to the above configuration, when the processing of the workpiece held by the workpiece spindle device is a sequence of processing by the turret device and processing by the tool spindle device, if it is confirmed that the separation shutter is closed, the tool spindle device can be protected from chips and other particles produced by the workpiece processing performed by the turret device, and tools for the tool spindle device are changed by the automatic tool changer in parallel with the processing.

1 is a perspective view showing a main structure of an embodiment of a multi-tasking machine; 1 is a side view showing a main structure of an embodiment of a multi-tasking machine; FIG. 2 is a side view showing a tool spindle device of the multi-tasking machine. FIG. 2 is a perspective view of the overall appearance of the multi-tasking machine. FIG. 2 is a side view showing the multi-tasking machine with the machine body cover removed. FIG. 1 is a diagram conceptually illustrating a control system for a multi-tasking machine. 10 is a flowchart showing processing in an automatic tool changing program. FIG. 10 is a simplified front view of the multi-tasking machine showing the switching state of the separation shutter. FIG. 10 is a simplified front view of the multi-tasking machine showing the switching state of the separation shutter.

An embodiment of the multi-tasking machine according to the present invention will be described below with reference to the drawings. FIGS. 1 and 2 are a perspective view and a side view showing the main structure of the multi-tasking machine of this embodiment. This multi-tasking machine 1 includes an opposed twin-axis lathe, in which a first workpiece spindle unit 3 and a second workpiece spindle unit 4 are arranged symmetrically to impart rotation to the gripped workpiece W, and a first turret unit 5 and a second turret unit 6 are arranged with multiple turret tools Ta corresponding to the machining of the workpiece W. In addition, a tool spindle unit 2 is provided in the center of the machine body to perform machining that is difficult to perform on a lathe.

The first and second work spindle devices 3, 4 (hereinafter, when describing both devices generically, they will be referred to as work spindle devices 3, 4) have a spindle rotatably mounted on a cylindrical headstock 12, to which is attached a chuck mechanism 11 that grips and releases the workpiece W to be machined. The chuck mechanism 11 rotates on the spindle when driven by a spindle motor, allowing the gripped workpiece W to be phased during machining and rotate at a predetermined speed.

The workpiece spindle devices 3 and 4 are mounted on the spindle slide 13 and are configured to move in the Z-axis direction on the front inclined surface of the bed 7. The center line of the spindle is designed to be horizontal and oriented in the width direction of the machine body, but in this embodiment, the Z-axis direction refers to the direction parallel to this center line. The spindle slide 13 is assembled to slide on a guide rail parallel to the Z-axis, and a ball screw mechanism enables linear movement by converting the rotational output of the Z-axis servo motor 14 into linear motion.

Next, the first turret device 5 and the second turret device 6 (hereinafter, when describing both devices collectively, they will be referred to as turret devices 5 and 6) use tools arbitrarily selected from a plurality of turret tools Ta to perform predetermined processing, such as cutting, on the workpiece W. The turret devices 5 and 6 are configured such that a plurality of turret tools Ta are attached at equal intervals in the circumferential direction to a disk-shaped turret 15, which serves as a tool rest, and any turret tool Ta can be rotated and indexed to a processing position on the circumference by controlling the rotation of an indexing servo motor 16.

To move the turret tool Ta to the machining position, the turret devices 5 and 6 are configured to move the turret 15 in the YL-axis and XL-axis directions, which are angled 45 degrees from the horizontal and vertical directions, on an XY plane perpendicular to the Z-axis. The bed 7 has a rear inclined surface 701 parallel to the YL-axis, on which a roughly triangular base slide 17 is mounted so that it can slide along the YL-axis. Furthermore, a turret slide 18 is mounted on the base slide 17 so that it can slide along the XL-axis. The base slide 17 and turret slide 18 are each equipped with a ball screw mechanism, and the rotational output of the YL-axis servo motor 19 or XL-axis servo motor 20 is converted into linear motion, enabling linear movement in each axial direction.

Next, Figure 3 is a side view showing the tool spindle unit 2. The tool spindle unit 2 has a spindle servo motor and tool spindle built into the spindle head 21, and various spindle head tools Tb housed in the automatic tool changer 8 (see Figure 5) can be replaced using the tool mounting section located at the bottom end of the spindle head 21. The spindle head 21 is rotatably attached to the spindle slide 22, and is configured so that the rotation of the B-axis motor 23 is transmitted via a rotation transmission mechanism.

The tool spindle unit 2 is mounted on the bed 7 so that the base slide 25 slides parallel to the Y-axis direction, and the spindle slide 22 is attached to the base slide 25 so that it slides vertically in the X-axis direction. Both the spindle slide 22 and the base slide 25 have a ball screw mechanism that converts the rotational output of the Y-axis servo motor or X-axis servo motor into linear motion, enabling linear movement in each axis direction.

Next, Figure 4 is an oblique view of the overall appearance of the multitasking machine 1. In addition to the aforementioned first workpiece spindle device 3, the multitasking machine 1 also includes an automatic tool changer 8 and an automatic workpiece transport device 9, which are covered by a machine body cover 100. The gantry-type automatic workpiece transport device 9 is installed so as to protrude upward from the machine body cover 100, and is configured to move the gripped workpiece W inside the machine body. The automatic tool changer 8 has a tool magazine installed in a magazine cover 101 that protrudes forward from the front of the machine body.

5 is a side view showing the multitasking machine 1 with the machine body cover 100 removed. The multitasking machine 1 has an automatic workpiece transport device 9 attached to a tower-shaped frame structure 30, and a chuck mechanism 32 that grips the workpiece W can move in three axial directions. The automatic tool changer 8 has a tool magazine 31 mounted on top of an exchanger main body 33 and supported by two pillars and a frame-structured support structure connected to the bed 7. The automatic tool changer 8 includes a shift device configured within the exchanger main body 33 for raising and lowering the spindle head tool Tb, and a tool changer 35 for changing the spindle head tool Tb between the shift device and the tool spindle device 2.

The multitasking machine 1 has machining chambers for the workpiece spindle units 3 and 4 behind the front doors 105 and 106. Workpieces W can be machined simultaneously in each machining chamber, and tools can also be changed in the tool spindle unit 2. However, if these tasks are performed simultaneously in one space, flying chips and coolant can adhere to the spindle head tool Tb and the workpiece W, causing adverse effects. In particular, if chips or other particles adhere to the spindle head tool Tb during tool changes in the tool spindle unit 2, proper installation cannot be achieved, resulting in reduced machining accuracy. Therefore, the multitasking machine 1 is provided with two separation shutters 28A and 28B on both sides of the tool spindle unit 2 in the width direction, as shown by the dashed lines in FIG. 1.

The separation shutters 28A, 28B are movable in the longitudinal direction of the machine body along the Y-axis guide rail, and are configured to be opened and closed by the extension and retraction of air cylinders arranged in the same axial direction. The multitasking machine 1 can switch between machining chambers using the separation shutters 28A, 28B, and as shown in Figure 8, can be divided into a first machining space 10A consisting of the first workpiece spindle unit 3 and turret unit 5, a second machining space 10B consisting of the second workpiece spindle unit 4 and second turret unit 6, and a tool exchange space 10C for the tool spindle unit 2.

Figure 6 is a conceptual diagram of the control system of the multi-tasking machine 1. The control device 50 that drives the multi-tasking machine 1 has a microprocessor (CPU) 51, ROM 52, RAM 53, non-volatile memory 54, etc. connected via a bus line 57. The CPU 51 controls the entire control unit, and the ROM 52 stores the system programs and control parameters executed by the CPU 51, while the RAM 53 temporarily stores calculation data, etc.

The control device 50 is equipped with a programmable logic controller (PLC) 56 connected to an I/O unit 55, and a sequence program created in ladder format controls the drive units of various machining devices, such as the tool spindle unit 2 of the multi-tasking machine 1. Machining programs and the like are stored in non-volatile memory 54, and each function command is converted into the required signal by the sequence program, which is then output from the I/O unit 55 to the tool spindle unit 2 and the like.

In the multitasking machine 1, continuous workpiece machining is performed by the first or second turret unit 5, 6 and the tool spindle unit 2, and the tool spindle unit 2 is replaced with a corresponding tool by the automatic tool changer 6. In this embodiment, an automatic tool change program is stored to efficiently perform such tool changes. Figure 7 is a flowchart showing the processing of the automatic tool change program. In particular, continuous workpiece machining by the first turret unit 5 and the tool spindle unit 2 will be described, but the same applies to continuous workpiece machining by the second turret unit 6 and the tool spindle unit 2.

8 and 9 are simplified front views of the multitasking machine 1 showing the switching status of the separation shutters 28A and 28B. Because the separation shutters 28A and 28B move in the Y-axis direction, which penetrates the drawing, they are only shown in the closed state separating the interior space of the machine. First, when workpiece machining is performed by the first turret unit 5, the separation shutter 28A is closed to separate the first machining space 10A from the tool exchange space 10C (S101). Next, the first turret unit 5 rotates and indexes to position a corresponding one of the multiple turret tools Ta attached to the turret 15 at a machining position on the circumference, and machining is performed with the turret tool Ta on the workpiece W gripped by the chuck mechanism 11 of the first workpiece spindle unit 3 (S102).

Next, the spindle head tool Tb is replaced in preparation for subsequent machining by the tool spindle unit 2. To do this, the separation shutter 28A must be closed, and an open/close determination is made based on a signal from a detection switch provided on the air cylinder (S103). If the separation shutter 28A is closed (S103: YES), the spindle head tool Tb is replaced on the tool spindle unit 2 (S104). Tool replacement performed by the automatic tool changer 6 involves the spindle head tool Tb taken out of the tool magazine 31 being lowered by the shift device, and then being replaced with the spindle head tool Tb attached to the tool spindle unit 2 by the tool changer 35.

In the past, a tool change command (T code) to the tool spindle unit 2 only caused movement in preparation for the change, but in this embodiment, the T code command processing has been modified so that the process up to tool change by the tool changer 35 is carried out continuously. Therefore, even if machining is being performed by the first turret unit 5 in the first machining space 10A, tool change is carried out in parallel within the tool change space 10C separated by the separation shutter 28A. Then, when workpiece machining is completed (S105: YES), the separation shutter 28A opens (S106), and machining is performed by the tool spindle unit 2 (S107), as shown in FIG. 9.

When changing tools on the tool spindle unit 2, the separation shutter 28A must be closed during machining to avoid being affected by chips and the like. However, if the separation shutter 28A cannot be closed due to a malfunction or other reason (S104: NO), a warning is displayed on the operation panel 110 or other device located at the center of the front of the machine body while machining continues on the first turret unit 5 (S111). However, machining by the first turret unit 5 continues, and tool change on the tool spindle unit 2 is carried out only partway. In other words, the tool change command at this time is a tool call command to prepare for change, as in the past (S112).

Therefore, in the automatic tool changer 6, the spindle head tool Tb removed from the tool magazine 31 is lowered by the shift device and waits in a position ready for exchange with the tool changer 35. The end of machining being performed in the first machining space 10A is then confirmed (S113). Once machining is completed (S113: YES), a tool change is then performed based on the tool change command (M code). That is, the spindle head tool Tb waiting outside the machining chamber is exchanged for the spindle head tool Tb attached to the tool spindle device 2 by the tool changer 35 (S114). Then, machining is performed by the tool spindle device 2 (S107), as shown in FIG. 9.

Incidentally, in the multi-tasking machine 1, machining may be performed simultaneously on the second workpiece spindle unit 4 when a tool is changed on the tool spindle unit 2. In such cases, the open/closed state of the separation shutter 28B is also checked, and a tool change on the tool spindle unit 2 is performed in step S104 or steps S112 and S114 corresponding to that open/closed state. Furthermore, in this embodiment, there may be cases in which continuous workpiece machining is performed on a workpiece W held by the second workpiece spindle unit 4 by the second turret unit 6 and the tool spindle unit 2, and even in such cases, a tool change on the tool spindle unit 2 is performed in the same manner.

According to this embodiment, when consecutive workpiece machining is performed by the first or second turret unit 5, 6 and the tool spindle unit 2, even if machining is being performed by one or both of the first and second turret units 5, 6, it is possible to perform a tool change on the tool spindle unit 2 by closing the separation shutters 28A, 28B. Therefore, machining by the tool spindle unit 2 can be started after machining by the first or second turret unit 5, 6 has finished, without waiting for a tool change, which shortens the machining time.

Although one embodiment of the present invention has been described, the present invention is not limited to this embodiment, and various modifications are possible without departing from the spirit of the present invention.
For example, the tool change flowchart shown in Fig. 7 is an explanation that takes into consideration only the machining of the first turret unit 5. The multi-tasking machine 1 is configured as a bilaterally symmetrical opposed two-spindle lathe, but the present invention may also be applied to a multi-tasking machine such as a single-spindle lathe in which the first turret unit 5 and the tool spindle unit 2 are provided relative to the first workpiece spindle unit 3.

REFERENCE SIGNS LIST 1... Multi-tasking machine 2... Tool spindle device 3... First workpiece spindle device 4... Second workpiece spindle device 5... First turret device 6... Second turret device 8... Automatic tool changer 9... Automatic workpiece transport device 10A... First machining space 10B... Second machining space 10C... Tool change space 11... Chuck mechanism 15... Turret 21... Spindle head 28A, 28B... Separation shutter 31... Tool magazine 35... Tool changer 50... Control device Ta... Turret tool Tb... Spindle head tool

Claims (2)

a work spindle device that rotates the work held by the chuck mechanism;
a turret device that performs machining on a workpiece held by the workpiece spindle device using a turret tool that is rotationally indexed from among a plurality of turret tools;
a tool spindle device that performs machining on a workpiece held by the workpiece spindle device by rotating an exchangeable spindle head tool;
an automatic tool changer that changes the spindle head tool for the tool spindle device;
an openable and closable separation shutter provided between the turret device and the tool spindle device;
a control device that controls the driving of each of the devices and the separation shutter;
and
When the separation shutter is closed in a machining process in which continuous machining is performed on a workpiece held by the workpiece spindle device using the turret device and the tool spindle device, the control device causes the automatic tool changer to change the spindle head tool of the tool spindle device in parallel with machining of the workpiece by the turret device,
According to the detection result of the open/closed state of the separation shutter, if it is confirmed that the separation shutter is closed, the spindle head tool is replaced in parallel with the processing of the workpiece by the turret device, and if it is not confirmed that the separation shutter is closed, the spindle head tool is made to wait at a position just before replacement, and the spindle head tool is replaced after the processing of the workpiece by the turret device is completed . the work spindle device and the turret device have an opposing two-axis structure consisting of a first work spindle device and a second work spindle device, and a first turret device and a second turret device, with the tool spindle device disposed therebetween, and two separation shutters are disposed on both sides of the tool spindle device in the width direction to separate the first turret device and the second turret device,
2. The multi-tasking machine according to claim 1, wherein the control device detects the open/closed states of the two separation shutters during a machining process in which a workpiece held by the first or second workpiece spindle device is continuously machined by the corresponding first or second turret device and the tool spindle device, and causes the automatic tool changer to change the spindle head tool of the tool spindle device.