JPS6350125B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a numerically controlled multi-axis machine tool incorporated into a transfer machine.

Generally, three-dimensional numerical control (NC) machine tools are equipped with one main spindle for machining, and the necessary machining is performed by moving the spindle or the workpiece to a predetermined processing position. When it is necessary to change a tool, NC machine tools either use an automatic tool changer (ATC) to change the tool, or use a turret to replace the spindle with the tool with the spindle at the machining position.

Recently, from the perspective of FMS (flexible manufacturing system), it has become necessary to incorporate processing units with NC into transfer machines. This requirement is to realize efficient processing with high flexibility in the area of medium-sized, medium-volume production. However, conventional processing units with NC cannot be directly integrated into transfer machines due to various problems. In other words, when incorporating a processing unit with 3D NC into a transfer machine, it is difficult to control the position of the workpiece using the transfer machine's workpiece transport device.
Basically, the workpiece side is fixed, and the processing unit with NC controls the position of three-dimensional movement with respect to the spindle. At this time, the following problems occur with conventional 3D NC processing units.

(1) In transfer machines, single-axis three-dimensional
If a processing unit with NC is used, the number of stations will be required depending on the processing content, which will significantly increase the initial equipment cost and eliminate the benefits of equipment improvement.

(2) Conventional transfer machines are mainly configured with multi-axis head type dedicated processing units, so the transfer pitch (distance between dedicated processing units) between stations can be set small. On the other hand, when a single-axis NC machining unit is incorporated into a transfer machine, the movement range of the machining spindle increases depending on the type of machining, so the transfer pitch of the transfer machine must be significantly increased. As a result, the transfer machine occupies a larger equipment area than conventional ones. Furthermore, if the movement range of the spindle becomes large, the processing unit with NC will not be able to secure the required movement range of the spindle on the existing transfer machine, and it will not be possible to install it as is.

(3) If the movement distance of the spindle is long, the loss time during movement of the spindle will be large, and this will inevitably reduce the productivity of the transfer machine.

(4) When tools need to be replaced, the conventional ATC type or turret type has a limited operating speed, which impairs the function of the transfer machine as a mass production machine.

The purpose of the present invention is to reduce the movement range of the tool head of a NC-equipped processing unit as much as possible, to enable the NC-equipped processing unit to be incorporated into a transfer machine, and to reduce the time required for moving the tool head and changing tools. The aim is to minimize the size and increase machining efficiency.

Based on the above object, the present invention provides a tool head whose position can be controlled by numerical control, with a plurality of spindles and tools spaced apart in the transfer direction, and these spindles and tools correspond to the machining position of the workpiece. The moving range of the tool head is set to be small in accordance with the distance between the tools in the transfer direction.

Hereinafter, the present invention will be specifically explained based on an embodiment shown in the drawings.

First, FIG. 1 shows a numerically controlled multi-axis machine tool 1 for transfer machines according to the present invention. This numerically controlled multi-axis machine tool 1 has a Y-direction movable table 4 slidably placed on the Y-direction guide surface 3 of a base 2, and a movable column 6 slidable on the X-direction guide surface 5 of the movable table 4. A tool head 8 is slidably attached to a Z-direction guide surface 7 of the movable column 6. Here, the Y direction corresponds to the transfer direction of the transfer machine 50, which will be described later, and the X direction corresponds to the advance/retreat direction of the tool head 8, that is, the processing direction, and these X-Y directions are orthogonal in the horizontal plane. in a state.
Further, the Z direction corresponds to the vertical direction of the tool head 8, and is set perpendicular to the plane in the XY direction. The tool head 8 slidably supports a plurality of, for example, two main shaft cylinders 9 and 10 in the Y direction, that is, the transfer direction, in a state where they can selectively protrude at two positions, upper and lower. Of course, these main shaft cylinders 9, 10 hold appropriate tools 13, 14 by rotatable main shafts 11, 12. The movable table 4 is moved in the Y direction (transfer direction) by a feed motor 46 as a drive means, and the movable column 6 is moved forward and backward by the main shaft 1.
1 and 12 in the X direction (processing direction), and a feed motor 48 is used to move the tool head 8 up and down. Of course, these feed motors 46, 47, 4
8 is connected to the movable table 4, the movable column 6, and the tool head 8, respectively, by means such as a feed screw (not shown), and the amount of rotation thereof can be detected by an encoder or the like. The main shafts 11 and 12 and the tools 13 and 14 are rotated by the rotational force of a main shaft motor 15 attached to the back side of the movable column 6.

Now, as shown in Fig. 2, the tool head 8 is placed at a predetermined distance in the Y direction (transfer direction), and
Storage holes 16 and 17 are formed in the X direction, and the main shaft cylinders 9 and 10 are held slidably in the X direction at the respective storage holes 16 and 17. These main shaft cylinders 9 and 10 rotatably support main shafts 11 and 12 by bearings 18 and 19, respectively. As mentioned above, the main shafts 11 and 12 hold the tools 13 and 14 at their respective tips, and their rear ends only rotate while allowing movement in the X direction relative to the sleeves 22 and 23 due to splines 20 and 21. They fit together in a state that accepts them. These sleeves 22 and 23 are connected to bearings 24 and 2, respectively.
5 rotatably supported in storage holes 16 and 17, and gears 26 and 27 are fixed at the rear end side. These gears 26 and 27 are connected to the aforementioned main shaft motor 1.
It is engaged with a drive gear 29 attached to a motor shaft 28 of No. 5. The tool head 8 also forms a cam plate storage chamber 31 facing the cylinder 30 and the two storage holes 16 and 17 at the center. The cylinder 30 is connected to a pressure source through ports 32 and 33 at both ends, and has a piston 35 slidably housed therein with its open end closed with a lid 34. The piston rod 36 of this piston 35
is slidably and rotatably held in the axial direction in the guide hole 37 of the tool head 8, and the cam plate 38 is fixed in the cam plate storage chamber 31, and the pinion 39 is fixed at the end. is forming. This pinion 39 is engaged with a rack 41 rotatably inserted into a guide hole 40. In addition,
This rack 41 is driven by a drive means (not shown). Then, as shown in FIG.
Two protrusions 42 and 43 are formed, and these protrusions 42 and 43 correspond to notches 44 and 45 formed on the outer periphery of the main shaft cylinders 9 and 10.

The numerically controlled multi-axis machine tool 1 described above operates as follows. First, the operator moves the rack 41 in the axial direction, rotates the cam plate 38, and engages the protrusion 43 with a desired notch 45 corresponding to the main shaft 12, for example. When pressure fluid is sent to the port 33 in this state, the piston 35 moves toward the piston rod 3.
6 is moved forward in the X direction. At this time, the engaged main shaft cylinder 10 projects from the tool head 8 together with the piston rod 36, and the tool 14 at the tip of the main shaft 12 is advanced to a suitable position for machining.
Thereafter, when the main shaft motor 15 is started, its rotation is transmitted to the main shaft 12 via the drive gear 29, gear 27, and spline 21, so that the tool 14 at the tip of the main shaft 12 is ready for necessary cutting. Note that since the rotation of the main shaft motor 15 is also transmitted to the main shaft 11 that is not engaged with the protrusion 42 of the cam plate 38, the tool 13 is in an idle state. Next, the numerically controlled multi-axis machine tool 1 controls the rotation amount of the feed motors 46 and 48 in the Y direction and the Z direction, moves the position of the main spindle 12 in the protruding state to the machining position, and at the same time controls the rotation amount of the feed motor 47 in the X direction. The rotation moves the movable column 6 forward and sends out the tool 14 of the main shaft 12 in a protruding state to the position of the workpiece 49. Of course, the rotational speed of the feed motor 47 is in a rapid feed state during air cutting, and automatically changes to the cutting feed speed from the time the tool 14 approaches the workpiece 49 until the machining is completed. Further, when the machining is completed, the feed motor 47 moves the tool 14 backward at a fast return speed.

Now, the maximum machining area in the transfer direction (Y direction) of this numerically controlled multi-axis machine tool 1 is the machinable area for the workpiece 49 in the transfer direction,
In other words, it can be defined as the total movement range in the transfer direction by each of the tools 13 and 14, where this is defined as A, the number of spindles in the transfer direction is n, and the movement range of the tool head 8 in the transfer direction, that is, each tool. When the movement range of 13 and 14 in the transfer direction is L, it is expressed by the following formula.

A≒L×n Here, the meaning of “≒ (approximately equal)” in the above formula includes overlapping adjacent movement areas L, as shown in FIG. The overlapping area of the movement area L is located approximately at the center of the workpiece 49, and is commonly used for the main shafts 11 and 12 in the transfer direction, for example, as a tool exchange position. Further, in this overlapping region, since the main shafts 11 and 12 can both move, different cutting operations can be performed on the workpiece 49 within that range without moving the workpiece 49 at that station.

Therefore, in this embodiment, the number of spindles n=
2, the movement range L of the tool head 8 is approximately 1/2 of the maximum machining range A, as shown in FIG.

Next, FIG. 4 shows a state in which the numerically controlled multi-axis machine tool 1 of the present invention is sequentially installed at each processing station in an in-line type transfer machine 50. The work 49 is intermittently fed in the transfer direction (Y direction) at regular intervals, that is, at intervals of transfer pitches P, by a work transfer device (not shown) of the transfer machine 50.
When the workpiece 49 stops at a predetermined station, the numerically controlled multi-axis machine tool 1 moves the tool head 8 forward in conjunction with the movement stop of the workpiece 49, and moves the workpiece 49 with the tool 14 of the main spindle 12 in the forward state.
Perform the necessary processing. As already mentioned, in this embodiment, the number of main axes in the transfer direction (Y direction) is n=2, so the movement range L of the tool head 8 is
is given by A/2, and the amount of movement of the numerically controlled multi-axis machine tool 1 in the Y direction, that is, in the transfer direction, is A/2. As a result, even when the transfer pitch P of the transfer machine 50 is small, the numerically controlled multi-axis machine tool 1 can be installed sequentially along the transfer machine 50 while securing the operating space and without mutual interference. It becomes possible. This also means that the transfer pitch P of the transfer machine 50 can be made as small as possible, which is effective in shortening the overall length of the transfer machine 50. In addition, the main shaft 11,
Since the moving distance of the spindle 12 in the Y direction becomes smaller, the loss time when moving the main axis is reduced to 1/n compared to that of a single axis. In addition, tool exchange is performed on spindles 11 and 12.
Because this is done by selectively advancing the ATC device, the replacement time is shorter than that of conventional ATC devices.

In the above embodiment, two tools 13 and 14 are arranged in the Y direction (transfer direction), but the number of tools installed may be three or more. can be set even smaller. Further, the installation positions of the plurality of tools may be different in height and may be shifted in the transfer direction. Further, the tool selection means is configured for each of the two main shafts 11, 12 by the cylinder 30, cam plate 38, and notches 44, 45, but this selection mechanism may be provided in common for the four main shafts 11, 12. It is also possible to replace it with other known ones. Further, the driving means in the transfer direction and the processing direction may be constituted by a cylinder. Furthermore, although FIG. 4 illustrates an in-line type transfer machine 50, this transfer machine can be constructed as a rotary type. In the case of a rotary transfer machine, the transfer direction is tangential to the transfer circle.

According to the present invention, since a plurality of spindles are arranged in the transfer direction, the amount of movement of the spindle can be made smaller than the maximum machining area. unit), the transfer machine can be made smaller, and since the amount of movement of the spindle is small, there is less loss time in spindle position control, and multiple tools can be selected by protruding in the machining direction. Compared to conventional ATC, the mechanism is simpler and the time required to change tools is reduced. The present invention is extremely significant in that it enables the incorporation of a numerically controlled multi-axis machine tool into a transfer machine and contributes to the development of FMS in transfer machines.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a numerically controlled multi-axis machine tool for transfer machinery according to the present invention, FIG. 2 is a horizontal sectional view of the spindle selection mechanism and spindle drive mechanism, and FIG.
The figure is a front view of the spindle selection means, Figure 4 is a plan view of the numerically controlled multi-axis machine tool of the present invention incorporated into an in-line transfer machine, and Figure 5 is a diagram showing the maximum machining area and movement area. It is an explanatory diagram showing a relationship. 1...Numerically controlled multi-axis machine tool, 2...Base,
3... Y direction guide surface, 4... Movable table, 5...
...X direction guide surface, 6...Movable column, 7...Z direction guide surface, 8...Tool head, 9, 10...Main shaft cylinder, 11, 12...Main shaft, 13, 14...Tool, 15... Main shaft motor, 27... Gear, 30...
...Cylinder, 35...Piston, 38...Cam plate, 39...Pinion, 41...Rack, 42,
43...Protrusion, 44,45...Notch, 46,4
7, 48...Feed motor, 49...Work, 50
...transfer machine.

Claims (1)

[Scope of Claims] 1. A numerically controlled multi-axis machine tool installed at the station of a transfer machine, which has a tool head having a plurality of spindles spaced apart in the transfer direction, and a tool head attached to each of the spindles and having its own machining area. It has a tool, a means for driving the tool head in the transfer direction, a means for selecting the main spindle, and a means for driving the selected main spindle in the machining direction, and the number n of spindles in the transfer direction, the number n of spindles for each tool, When the movement range of the tool head in the transfer direction is L, and the maximum machining area in the transfer direction by multiple tools is A, A≒L×n, the transfer direction of the tool head is larger than the machining area of the workpiece in the transfer direction. A numerically controlled multi-axis machine tool for transfer machinery, characterized by a small directional movement range.