JPS6134923B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a turret tool rest for a numerically controlled machine tool.

A numerically controlled machine tool has several basic operations that are absolutely required for its intended machining function. For example, in a typical numerically controlled lathe, the workpiece is rotated, the tool is moved relative to the workpiece in the radial and axial directions by two slide mechanisms, and the tool is automatically moved. This corresponds to the tool exchange operation for replacement use. In general, these operations are required to be able to operate independently,
Therefore, in order to satisfy this requirement, conventional numerically controlled lathes have been equipped with sufficient mechanisms and control means to perform each operation independently.
Among these, if we focus on the tool exchange operation, that is, the tool post, the tool exchange operation can be performed reliably and quickly.
Turret tool rests are often used because they have sufficient rigidity to support tools and are easy to avoid interference between tools other than the tool being used and the workpiece. However, when configuring a turret tool post, it is necessary to have means for controlling its rotational position and positioning, and in many cases these tend to be more complicated than the means for configuring other basic operations, reducing the reliability of the machine. This has become a major factor in the increase in machine costs, and has also become a factor pushing up machine costs.

In contrast, in recent years, a plurality of tools are arranged parallel to the axial direction of the workpiece on a slide table for moving the tool in the radial direction relative to the workpiece, and the necessary tools are moved by the movement of the slide table. is used relative to the workpiece. A numerically controlled lathe using a so-called comb-type turret has appeared. The feature of this lathe is that while it has the basic functions absolutely required of the numerically controlled lathe mentioned above, the mechanism does not require an independent means for automatically changing tools. Therefore, compared to the turret turret system,
Its structure is extremely simple, and it is excellent in terms of both reliability and cost. However, due to the way the tools are attached and arranged, tool support rigidity is weak, and setup work to avoid interference between unused tools and the workpiece becomes complicated. This method has disadvantages such as the amount of movement of the slide table in the radial direction being much larger than the amount of movement that is originally required, and it cannot be used in anything other than small-sized lathes.

The purpose of the present invention is to solve the above-mentioned comb blade type tool rest system concept,
In other words, by combining the advantages of changing tools using the slide table movement mechanism with the advantages of the turret tool post system, reliability and
It is an object of the present invention to provide a turret tool rest for a numerically controlled machine tool that has excellent workability and is advantageous in terms of cost.

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the drawings.

FIG. 1 is a conceptual diagram of a headstock sliding type numerically controlled lathe equipped with a turret tool rest according to the present invention, and FIG. 2 is a sectional view showing details of the turret tool rest.

In Fig. 1, 1 is a leg, 2 is a bed fixed to the top surface of leg 1, 3 is a main body with an L-shaped box structure fixed to the top surface of bed 2, and 4 is a main body 3 inserted through it. A guide bush 5 fitted in the hole 1 is arranged parallel to the center line of the guide bush 4.
A guide rod whose end is inserted into the main body 3 and whose other end is inserted into and supported by a block 6 fixed to the upper surface of the bed 2. The guide rod 7 rotates while gripping the workpiece and supports a main shaft arranged on the center line of the guide bush 4. a headstock 8 which is mounted on the guide rod 5 and is slidable in the direction of the center line;
1 is a servo motor that controls the sliding movement of the headstock 7 using a well-known feed screw mechanism; 9 is a main motor that is supported by the leg 1 and rotates the main shaft; It has a support shaft that is fitted and supported in a hole through which it is inserted, and holds multiple tools on its outer circumferential surface, and at the same time performs arbitrary selection and indexing of tools by rotating itself. , is a turret head that is slidable in the direction of its support axis, that is, in a direction perpendicular to the center line of the guide bush 4.

FIG. 2 shows details of the turret section including the turret head 10. Here, 10 is a turret head, 10a is a support shaft that is integrated with the turret head 10 and has the same central axis, 11 is a cutting tool held on the outer peripheral surface of the turret head 10, and 12 is a drill. 13 and 14 are main body 3
15 is a rotation preventing rod arranged parallel to the support shaft 10a and supported through the main body 3; 16 is a cylinder block provided on the support shaft 10a. The end of the piston 18 is fitted onto the outer periphery of the piston 18.
9 to form a cylinder having a right cylinder chamber 18a and a left cylinder chamber 18b, and is fitted onto the rotation stopper rod 15 via a bush 17 so as to be slidable in the axial direction. Reference numeral 20 indicates a positioning pin which is inserted into a guide hole 18c provided in the cylinder block 16 in parallel with the support shaft 10a so as to be movable in the axial direction, and is always urged in the projecting direction by a back-up spring 21. Reference numeral 22 indicates the support shaft 10a. A positioning plate 22a is fixed to the turret head 10 by a wedge-type fastening member 22a, and a positioning plate 23 is provided on its side surface, which is concentric with the support shaft 10a and corresponds to the positioning pins 20 and the number and angle of the tool mounting positions of the turret head 10. It is provided. 24 is the support shaft 10
A feed screw shaft 27 is rotatably supported by a bearing 26 fitted in a gear box 25 which is disposed on the center line of the main body 3 and is additionally fixed to the main body 3; A feed nut fitted and fixed to the opposite end of the support shaft 10a from the turret head 10, 28 a servo motor that rotates under the control of a numerical control device (not shown), 29 a feed screw gear fixed to the feed screw shaft 24, Reference numeral 30 denotes a motor shaft gear fixed to the output shaft of the servo motor 28, and the feed screw gear 29 and the motor shaft gear are always in mesh with each other to control the rotation of the output shaft of the servo motor 28 to the feed screw shaft 24 at a certain level. It constitutes a first transmission means that transmits transmission at a rotation ratio Rg.

31 is arranged parallel to the support shaft 10a, and the main body 3
and a bearing 32 fitted in the gearbox 25, respectively.
33 is a rotatably supported intermediate shaft, 34 is a fixed intermediate gear fixed to one end of the intermediate shaft 31 and constantly meshing with the feed screw gear 29 at a rotation ratio of 1/Rg, and 35 is an axially supported intermediate shaft 31 at the other end. A sliding intermediate gear 37, which is provided so as to be slidable and whose rotational direction is regulated by a sliding key 36, is pivotally supported by the main body 3 and swings, and one end thereof is engaged with the sliding intermediate gear 35. , a hydraulic cylinder 38 whose other end is supported by the main body 3
a switching lever connected to the tip of the piston 38a;
Reference numeral 39 denotes a support shaft gear fixed to the support shaft 10a that can mesh with the sliding intermediate gear 35 at a rotation ratio Rg, and these constitute a second transmission means equipped with a means for disconnecting the transmission operation. has been done.

Next, the operation of the turret tool rest having such a configuration will be explained. The servo motor 28 is rotated and the turret head 10 is retracted from the center line of the guide bush 4 to a range where the cutting edge of the cutting tool 11 has a distance greater than the maximum radius of the workpiece by the aforementioned feed screw mechanism, and the sliding intermediate gear A point is determined at which the teeth of the gear 35 and the support shaft gear 39 can mesh with each other, and this point is used as a tool change point to stop the turret head 10. Thereafter, the hydraulic cylinder 38 is operated and the switching lever 37 engages the sliding gear 35 with the support gear 38. When pressure oil is fed into the cylinder left chamber 18b formed in the cylinder block 16, the cylinder block 16
moves relative to the left with respect to the support shaft 10a, and as will be described later, the positioning plate 2 that was in pressure contact with the support shaft 10a
2, and at the same time, the positioning pin 20 comes out of the positioning bush 23 due to this action. As a result, the rotation direction of the support shaft 10a is no longer restricted. Next, when a rotation command is given to the servo motor 28 for a rotation angle corresponding to the rotation angle required for tool indexing of the turret head 10, the output shaft of the servo motor 28 rotates, and the rotation is sent from the motor shaft gear 30. Rotation ratio Rg for screw gear 29
The transmission is transmitted to the intermediate shaft 31 by the fixed intermediate gear 34 that meshes with the feed screw gear 29 at a rotation ratio of 1/Rg, and the rotation ratio of the sliding intermediate gear 35 and the support shaft gear 39 is Rg. The engagement of the two also rotates the support shaft 10a.
At this time, the feed screw shaft 24 and the support shaft 10a both have the same rotation speed of the rotation ratio Rg with respect to the output shaft of the servo motor 28, and are rotating in the same direction. This means that the feed nut 27 rotates together with the feed screw shaft 24,
The turret head 1 is rotated with no relative axial displacement between the feed screw shaft 24 and the feed nut 27.
0 is the only one performing rotational indexing operation.
Thus, when the servo motor 28 has completed the required rotation, the turret head 10 has completed its position indexing and will place the next required tool in its use position.

After that, when pressure oil is fed into the cylinder right chamber 18a of the cylinder block 16, the cylinder block 16
moves relative to the right direction with respect to the support shaft 10a, presses itself against the positioning plate 22, and at the same time, this movement causes the positioning pin 20 to move against the positioning bush 23.
The support shaft 10a is pushed in by the biasing force of the backup spring 21 to position the support shaft 10a in the rotational direction. That is, in this state, the turret head 10 has two guide shafts, the support shaft 10a and the rotation stopper rod 15 via the cylinder block 16 integrated with the support shaft 10a, and can slide in the axial direction along these. It becomes a possible mobile object. Then, the hydraulic cylinder 38 is operated in the return direction, and the switching lever 37 causes the intermediate sliding gear 35 to slide and disengage from the support shaft gear 39. Thereafter, when the servo motor 28 is rotated, the turret head 10 can move the support shaft 10a, that is, the turret head 10, forward or backward as desired by the required amount in a direction perpendicular to the center line of the guide bush 4 by the aforementioned feed screw mechanism.

If it becomes necessary to change the tool again, the turret head 10 can be moved back to the tool change point and the above operation can be repeated. At this time, the sliding intermediate gear 35 and the support shaft gear 39 mesh with each other without any problems because the phase relationship between the teeth when they are separated is completely restored and reproduced.

A headstock sliding type lathe having such a turret tool post has the basic operating functions of rotation of the main spindle, sliding operation of the headstock 7, sliding operation of the turret head 10, and tool exchange operation to perform desired product machining. I can do it.

Note that the use of the rotation of the servo motor 28 to rotate and index the turret head 10 is because the numerical control device considers the turret head 10 to have moved in the axis even though it does not make any sliding movement. Although the above considerations are required or a special correction function is required in the numerical control device, these can be handled in exactly the same way as in the case of the lathe having the wedge-shaped tool rest described above.

It goes without saying that the present invention is not limited to this embodiment, but can also be applied to, for example, general numerically controlled lathes with fixed spindles and other machine tools.

As described above, the turret tool rest for a numerically controlled machine tool according to the present invention has the following remarkable effects.

(1) While maintaining the basic functions necessary for a machine tool, there is no need for an independent operating mechanism or control means, making the machine configuration extremely simple.

(2) For example, when used in a numerically controlled lathe, the turret tool post system has the advantages of high tool support rigidity, and it is easy to avoid interference between tools other than the one being used and the workpiece, while at the same time, a comb-shaped tool It has the advantage of the simplification of the structure of the platform type, and compensates for the disadvantage of the comb-type tool rest in that the amount of movement of the slide table in the radial direction increases.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of a headstock sliding type numerically controlled lathe equipped with a turret turret according to the present invention, and Fig.
FIG. 3 is a detailed cross-sectional view of the turret tool post shown in the figure. 3...Main body, 10...Turret head, 10
a... Support shaft, 15... Rotating stopper rod, 16... Cylinder block, 20... Positioning pin, 22...
...Positioning plate, 23...Positioning button, 24
...Feed screw shaft, 27...Feed nut, 28...
Servo motor, 29...Feed screw gear, 30...
Motor shaft gear, 31...Intermediate shaft, 34...Fixed intermediate gear, 35...Sliding intermediate gear, 37...Switching lever, 38...Hydraulic cylinder, 39...Support shaft gear.

Claims (1)

[Claims] 1. a main body, a turret head having a support shaft that supports a plurality of tools and is rotatably and slidably supported by the main body, and positioning means for positioning the turret head only in the direction of rotation thereof;
a feed screw shaft disposed on the center line of the support shaft; a feed nut screwed into the threaded portion of the feed screw shaft and fixed to the support shaft; a drive source that rotates under numerical control; a first transmission means for transmitting the rotation of the output shaft of the drive source to the feed screw shaft; and a first transmission means for transmitting the rotation of the output shaft of the drive source to the feed screw shaft; A turret tool rest for a numerically controlled machine tool, comprising a second transmission means for causing rotation, and a decoupling means provided on the second transmission means for decoupling the transmission operation.