JP-7857254-B2 - Turret control device and turret lathe

JP7857254B2JP 7857254 B2JP7857254 B2JP 7857254B2JP-7857254-B2

Inventors

田口矩義

Assignees

シチズンマシナリー株式会社

Dates

Publication Date: 20260512
Application Date: 20230630

Claims (4)

A drive unit rotates a turret, which has multiple turret surfaces to which tool holders including tools are attached, around a predetermined center of rotation, A control unit that controls the operation of the drive unit, A receiving unit that receives input information regarding the tool layout, which specifies the arrangement of the tool holder on the turret surface, A center of gravity calculation unit calculates the center of gravity of the turret in the tool layout based on the information regarding the tool layout input to the reception unit, the information regarding the weight and center of gravity of the tool holder attached to the turret surface, and the information regarding the weight and center of gravity of the turret itself. The system includes an eccentricity calculation unit that calculates the eccentricity of the center of gravity position of the turret calculated by the center of gravity position calculation unit with respect to the position of the rotation center, The control unit controls the rotational speed of the turret by the drive unit based on the eccentricity, and is a turret control device.
The system includes a notification unit that displays information prompting a change in the tool layout, The turret control device according to claim 1, wherein the control unit controls the notification unit to notify information prompting a change in the tool layout when the eccentricity is greater than a preset threshold.
The system includes an overshoot detection unit that detects the amount of overshoot when an indexing operation is performed in which the turret is rotated at a predetermined rotational speed and the tool holder is stopped at the indexing position. The turret control device according to claim 1, wherein the control unit controls the drive unit to reduce the rotation speed when the overshoot amount is greater than a predetermined threshold.
A turret device including a turret having multiple turret surfaces that rotate around a predetermined center of rotation and to which tool holders including tools are attached, A spindle that holds the workpiece to be machined by the tool attached to the turret, The system includes a control device for controlling the spindle and the turret, The control device is a turret lathe having the turret control device described in any one of claims 1 to 3.

Description

This invention relates to a turret control device and a turret lathe. Some machine tools, such as automatic lathes, are equipped with a turret tool post. The turret of the tool post is formed in a rectangular prism shape, and tool holders, each fitted with a tool such as a drill or reamer, are attached to the multiple circumferential surfaces of this prism. Each turret surface is fitted with a tool holder selected according to the type of machining required for the workpiece. However, because machining is performed sequentially on the workpiece using the tool holders mounted on separate turret surfaces, it is necessary to rotate the turret and switch the tool holders to perform indexing operations as the machining process progresses. To shorten the tool holder switching time, a layout is sometimes adopted in which multiple tool holders used for machining are placed on adjacent turret surfaces in the rotational direction. Furthermore, especially when the number of tool holders attached to the turret is small, the tool holders are concentrated within a specific angular range of the turret. This results in an uneven weight balance around the center of rotation, which can cause the turret to overshoot during indexing operations with specific tool holders, making it impossible to precisely control the stopping position. Moreover, overshoot can occur again during the return movement to the correct stopping position after this overshoot, resulting in hunting behavior. Furthermore, even a slight deviation in the stopping position can cause a phase shift in the engagement of the curvilinear coupling when the turret rotates, resulting in a misalignment of the stopping position. Therefore, a turret rotation speed determination device has been proposed that increases the rotation speed of the turret while ensuring accuracy in the stopping position (see, for example, Patent Document 1). Japanese Patent Publication No. 2000-218470 This is a schematic perspective view showing the main external appearance of a turret lathe.This is a schematic front view showing the turret as seen from the direction of its axis C2.This is a block diagram showing the configuration of the control device 30 that controls the operation of the turret lathe.This figure shows the centroid position m1 of the tool holder T1 in the local coordinate system.This figure shows the centroid position m4 of the tool holder T4 in the local coordinate system.These are schematic diagrams showing the centroid position M'(X', Y') of the turret in the global coordinate system and the eccentricity δ from the rotation center (axis C2) according to the layout of an example tool holder, and show a layout in which the tool holders are concentrated within the angular range θ1.These are schematic diagrams showing the centroid position M′(X′, Y′) of the turret in the global coordinate system and the eccentricity δ from the rotation center (axis C2) according to the layout of an example tool holder, and show a layout in which the tool holders are distributed within the angular range θ2 (>θ1).This is a flowchart detailing the operation of the control device. Embodiments of the turret control device and turret lathe according to the present invention will be described below with reference to the drawings. Figure 1 is a schematic perspective view showing the main external appearance of the turret lathe 100, Figure 2 is a schematic front view showing the turret 22 as viewed in the direction of its axis C2, and Figure 3 is a block diagram showing the configuration of the control device 30 that controls the operation of the turret lathe 100. The turret lathe 100 is one embodiment of the turret lathe according to the present invention. The turret lathe 100 comprises the spindle 10 and turret device 20 shown in Figure 1, and the control device 30 shown in Figure 3. In addition to the spindle 10, turret device 20, and control device 30, the turret lathe 100 also includes a cutting fluid device for spraying cutting fluid onto the workpiece W during machining, but these are omitted from this explanation. Furthermore, the turret lathe 100 may also include a second spindle (rear spindle) and a second turret device. The spindle 10 is equipped with a holding mechanism at its tip, such as a collet chuck, which holds the workpiece W, mainly bar stock. The spindle 10 is rotatable around an axis C1 parallel to the z-axis direction (the longitudinal direction of the spindle 10), under the control of the control device 30. Furthermore, the spindle 10 is also rotatable parallel to the z-axis, under the control of the control device 30. The turret device 20 comprises a main body 21 and a turret 22. The turret 22 is formed, for example, in the shape of a regular dodecagonal prism. The shape of the turret 22 is not limited to a regular dodecagonal prism; it may be a regular decagonal prism, a regular octagonal prism, or other regular polygonal prisms. Furthermore, the shape of the turret 22 is no