JPH04129603A - Headstock for automatic lathe - Google Patents

Abstract

PURPOSE:To perform high speed rotation during a cutting work and to perform high-speed and accurate division during division of a work by effecting division rotation of a main spindle after the main spindle is separated away from a rotary transmission shaft by means of a switching means, and effecting division of the work. CONSTITUTION:A gear, such as a gear 55 on the dive side, and a C shaft motor 51 are separated away from a main spindle 2 during machining by means of a fixed cutter 11. The main spindle 2 is rotated through coupling of a spline 41 between a rotary transmission shaft 4 and the main spindle 2 with the aid of a spindle motor 3. Thus, high-speed rotation of the main spindle 2 is practicable through reduction of the generation of vibration and noise during machining. During machining by using a rotary cutter 12, the main spindle 2 is separated away from the spindle motor 3 and division of a work W is effected through division rotation of the main spindle 2 with the aid of only the C shaft motor 51. Thereby, load inertia during rotation is reduced, and high-speed and accurate division of the work W can take place.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to the headstock of an automatic lathe, and particularly to an automatic lathe that continuously rotates a workpiece and processes it with a fixed cutter, and also indexes the workpiece and processes it with a rotating cutter. Regarding the headstock of a lathe.

(Prior art) The spindle that has chucked the workpiece is continuously rotated at a predetermined speed, and the workpiece is turned using a fixed cutting tool such as a cutting tool, and the spindle is rotated in sections to index the workpiece.
2. Description of the Related Art There is a headstock of an automatic lathe that can perform secondary processing such as drilling using a rotating cutting tool such as an end mill or a drill.

Among such headstocks, there are those in which the main shaft is rotated at high speed and rotated in divided rotations by one motor, and those in which the main shaft is rotated at high speed and rotated in divided rotations by two motors, respectively.

In other words, when a single motor is used, the rotation is usually transmitted by a belt or the like to rotate the main shaft at high speed, and when indexing is performed, the motor is stopped at a predetermined position, and then the indexing position is determined by a positioning means or the like. .

In addition, when using two motors, a spindle motor that rotates at high speed for turning and a C-axis motor that rotates separately for indexing the workpiece are connected to the main shaft via belts, gear drives, etc. When turning is performed using a cutting tool, the main shaft is rotated by a spindle motor, and when drilling or the like is performed using a rotary cutter, the main shaft is rotated in parts by a C-axis motor.

(Problems to be Solved by the Present Invention) However, when conventionally configured to perform high-speed rotation and divided rotation with one motor, one motor has two functions of high-speed rotation and divided rotation. Therefore, the number of indexing operations is limited, and if belt drive is used, there is a problem in that the indexing position inevitably shifts during divided rotation, making it impossible to accurately index the workpiece.

Also, when using two conventional motors,
Since the main shaft and spindle motor are always connected,
When a workpiece is indexed by the C-axis motor and the indexed position is clamped, the spindle motor rotates in conjunction with the workpiece, thereby increasing the load inertia during divided rotation. For this reason, there is a problem that the indexing takes time and the indexing becomes inaccurate.

The present invention was made in view of these problems, and is an automatic lathe that is capable of high-speed rotation of a workpiece during turning processing and is capable of indexing the workpiece at high speed and accuracy. The purpose is to provide a headstock.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a headstock for an automatic lathe in which a workpiece is continuously rotated and machined by a fixed cutter, and the workpiece is rotated in sections to be indexed and machined by a rotary cutter. , comprising a rotation transmission shaft and a main shaft, a chucking means for inserting a workpiece into these shafts and chucking the tip of the workpiece; a continuous rotation driving means for continuously rotating the rotation transmission shaft and the main shaft via a belt; A switching means for connecting or disconnecting the rotation transmission shaft and the main shaft, and an indexing means for rotating the main shaft in parts and indexing the workpiece after the main shaft is separated from the rotation transmission shaft by the switching means. It is characterized by:

(Function) According to the above configuration, during machining with a fixed blade, the continuous rotation drive means rotates the rotation transmission shaft and the main shaft via the belt.

In this case, the rotation transmission shaft and the main shaft are connected by the switching means, and the indexing means is not connected to the main shaft, so that the main shaft can be rotated at high speed.

On the other hand, when machining with a rotary cutter, the main shaft is separated from the rotation transmission shaft by the switching means, and then the indexing means rotates the main shaft in parts to index the workpiece. It can be rotated.

Therefore, when indexing a workpiece, the main shaft can be completely separated from the continuous rotation drive means and rotated in divided rotations, which reduces the load inertia during divided rotation and enables high-speed and accurate indexing. become.

(Embodiment) Hereinafter, one embodiment of the headstock of an automatic lathe according to the present invention will be described based on the drawings.

FIG. 1 is a cross-sectional view showing the overall configuration of this embodiment, and the headstock 1 of this apparatus has a main spindle 2 that inserts and chucks a workpiece W, which is continuously rotated at high speed by a spindle motor 3. A fixed cutting tool 11 such as a cutting tool installed in front of the workpiece W is used to turn the workpiece W, and the main shaft 2 is rotated in sections to index the workpiece W.
For example, it is configured so that drilling and the like can be performed alternately using a rotary cutting tool 12 such as an end mill or a drill.

The headstock 1 has the above-mentioned main spindle 2, and the workpiece W is inserted behind and coaxially with the main spindle 2 in the same way as the main spindle 2, and a rotation transmission is transmitted to which high-speed rotation is transmitted from the spindle motor 3 during turning with a fixed blade. Shaft 4 and bearing 91.92 respectively
etc., so that it can rotate freely.

The main shaft 2 is provided with a chuck 21 at its tip for chucking the workpiece W, and a chuck 21 at the center thereof.
A toggle mechanism 22 is provided in conjunction with the toggle mechanism 22 to apply an external force to the chuck 21 when chucking the workpiece W. The toggle mechanism 22 is provided with a sleeve 22a having an inclined surface whose rear end is cut diagonally so as to be rotatable and slidable in the axial direction.
The lever 22b is slid to press the protrusion of the lever 22b by its inclined surface, and the lever 22b is swung about the fulcrum 22c to operate the chuck 21 and chuck the workpiece W.

A spline 23 having at least three key grooves extending in the axial direction is formed on the side surface of the rear end of the main shaft 2, while a spline 23 having at least three key grooves extending in the axial direction is formed in front of the spline 23. The passive side clutch cone 54 to be joined is fixed.

Further, the spindle motor 3 is provided with a pulley portion 31 on which the V-belt 32 is passed, and in order to rotate the rotational transmission shaft 4, the spindle motor 3 continuously rotates the pulley portion 31 at a constant high speed. let

Further, as described above, the rotation transmission shaft 4 is inserted through the workpiece W and is rotatably mounted on the headstock 1 by a bearing 92. A spline 41 having the same shape as the spline 23 of the main shaft 2 is formed, and a pulley part 42 to which the rotation of the spindle motor 3 is transmitted via the V-belt 32 is formed at the center thereof, and further at the rear end thereof. A fixed position stop sensor 43 is provided to detect whether or not the rotation transmission shaft 4 is stopped at a predetermined position (angular change).

As shown in FIG. 2, the splines 23.41 of the main shaft 2 and the rotation transmission shaft 12 are engaged with each other via bosses 65, and the rotation transmission shaft 4 and the main shaft are engaged with each other through bosses 65. A switching mechanism 6 is provided as a switching means for switching the connection with the main shaft 2, and an indexing mechanism 5 is provided as an indexing means for rotating the main shaft 2 in divisions and indexing the workpiece in cooperation with the switching mechanism 6. .

The switching mechanism 6 includes a connecting portion 61 that connects or disconnects the main shaft 2 and the rotation transmission shaft 4, and a switching drive portion 62 as a switching means that slides the connection portion 61 to switch the connection between the main shaft 2 and the rotation transmission shaft 4. The connecting portion 61 and the switching drive portion 62 are connected via a rod 63.

The connecting portion 61 includes an outer ring portion 64 to which one end of the rod 63 is connected, an outer bearing 94 attached to the inner periphery of the outer ring portion 64, and an indexing mechanism supported by the outer bearing 94 to be described later. Drive side gear 55 constituting 5
and an inner bearing 93 attached to the inner periphery of the drive side gear 55, and is rotatably supported inside the inner bearing 93 and engaged with the spline 23 of the main shaft 2 and the spline 41 of the rotary transmission shaft 4. As shown in FIG.
It consists of a boss 65 that slides on the top.

In this embodiment, the length of the boss 65 is made shorter than the length of the spline 23 of the main shaft 2.
When sliding in the direction, all the bosses 65 move onto the main shaft 2, and the main shaft 2 and the rotation transmission shaft 4, which were connected via the boss 65,
Make sure that they are completely separated.

The switching drive section 62 transmits an output from a hydraulic cylinder or the like (not shown) to one end of the rod 63 via a lever 62a, and a connecting section 61 connected to the other end of the rod 63.
Outer ring portion 64, drive side gear 55, and boss 65
etc. at the same time in the axial direction of the main shaft 2 or the rotation transmission shaft 4.

As shown in the same figure, the indexing mechanism 5 also includes a C-axis motor 51 that rotates the pinion 52 in parts, an idle gear 53 that meshes with the pinion 52 and transmits the rotation of the C-axis motor 51, and a bearing in the connecting part 61. A drive side gear 55 is rotatably supported between 93 and 94 and meshes with the idle gear 53 according to the operation of the switching mechanism 6, and a drive side gear 55 is fixed to the main shaft 2 and frictionally joined to the drive side gear 55. and a passive side clutch cone 54 constituting a clutch.

Then, the driving side gear 55 and the passive side clutch cone 5
4 have friction slopes 55a and 54a, respectively.
is formed, and when the drive side gear 55 moves in the direction of the main shaft 2 and both friction slopes 55a and 54a are frictionally joined, a gear portion 55b formed on the upper outer periphery of the drive side gear 55
meshes with gear portion 53b of idle gear 53, main shaft 2 and C-axis motor 51 are connected via pinion 52, idle gear 53, etc., and from C-axis motor 51 to main shaft 2
It is configured such that the divided rotation is transmitted to and indexes the workpiece W.

As shown in FIG. 1, the headstock 1 having the above-mentioned configuration slides on a guide table 11 formed on the base 10 of the device via a servo motor or a ball screw (not shown). It is composed of

Next, the operation of the headstock configured as described above will be explained with reference to the drawings. However, first the turning process is performed using a fixed blade, and then the drilling process is performed using a rotating blade.

First, in order to perform turning processing using the fixed cutter 11,
The boss 65 is positioned by the switching drive unit 62 on the spline 23 of the main shaft 2 and on the spline 41 of the rotation transmission shaft 4, and the main shaft 2 and the rotation transmission shaft 4 are connected (see FIG. 1 or 2). ), and in that state, for example, a programmable controller (not shown) (hereinafter referred to as P
The spindle motor 3 is driven by a command from a motor such as C.

Then, the pulley part 31 rotates, and the rotational force is applied to the pulley part 31 and transmitted to the rotating power transmission shaft 4 via the V-belt 32 that is passed to the pulley part 31.
The rotation transmission shaft 4 is transmitted to the pulley portion 42 to rotate the rotation transmission shaft 4. The rotational force is transmitted to the boss 65 via the spline connection between the spline 41 of the rotation transmission shaft 4 and the boss 65, and further transmitted to the main shaft via the spline connection between the boss 65 and the spline 23 of the main shaft 2. 2 and rotates the main shaft 2.

At this time, as shown in FIG. 1 or 2, the gear portion 55b of the drive side gear 55 is replaced by the gear portion 53b of the idle gear 53.
The friction slope 55 of the drive side gear 55 does not mesh with the
a is a passive clutch cone 54 attached to the main shaft 2;
Since the C-axis motor 51 is not in contact with the friction slope 54a of
and the main shaft 2 are separated.

Therefore, according to this embodiment, during machining with the fixed cutter 1, the main shaft 2 rotates in a state separated from the drive side gear 55, idle gear 53, and other gears and the C-axis motor 51, and the drive side gear 55 and Since large-diameter parts such as the idle gear 53 do not rotate, the main shaft 2 can be rotated at high speed while reducing noise due to vibration and wind noise.

In addition, since the rotation is transmitted from the spindle motor 3 to the main shaft 2 by a spline connection via the boss 65 between the main shaft 2 and the rotation transmission shaft 4, vibration and noise are prevented from occurring when the main shaft 2 rotates at high speed. It can be further reduced.

Next, drilling is performed using the rotary blade 12.

In this case, first, the fixed position stop sensor 43 detects whether or not the main shaft 2 and the rotation transmission shaft 4 are stopped at a predetermined position (angle), and then the machining cycle is started. If the main shaft 2 is not stopped at a predetermined position, the spindle motor 3 is rotated by a command from a PC or the like to position the main shaft 2 at a predetermined position.

When the main shaft 2 is positioned at a predetermined position, the switching drive section 62 moves the connecting section 61 forward, that is, in the direction of the main shaft 2, via the rod 63 in response to a command from a PC or the like.

Then, the boss 65 of the connecting portion 61 completely moves onto the spline 21 of the main shaft 2 as shown in FIG. 3 while engaging the spline 41 of the main shaft 2 and the rotation transmission shaft 4, and
The connection between the rotation transmission shaft 4 and the rotary transmission shaft 4 is disconnected.

Further, as shown in the same figure, the drive side gear 55 is pressed against the passive side clutch cone 54 fixed to the main shaft 2, and its friction slope 55a is frictionally connected to the friction slope 54a of the passive side clutch cone 54, and The gear part 55b on the upper part of the driving side character 5 meshes with the gear part 53b of the idle gear 53.

Therefore, the drive side gear 55 is connected to the pinion 52 via the idle gear 53, so when the C-axis motor 51 rotates the pinion 52 in divided rotations, the drive side gear 55 rotates in divided rotations via the idle gear 53. Then, the rotational force is transmitted to the passive side clutch cone 54 that is frictionally connected to the drive side gear 55, the main shaft 2 rotates, and the workpiece W is indexed.

At that time, the boss 65 has completely moved onto the spline 23 of the main shaft 2, and the main shaft 2 is disconnected from the rotational transmission shaft 4 and the spindle motor 3, while the split rotation from the C-axis motor 51 is carried out by the pinion 52, the idle The transmission is carried out through the gear 53, the driving gear 55, the passive clutch cone 54, and the main shaft 2, so the main shaft 2 is connected to the spindle motor 3.
Since the workpiece is rotated separately and divided, the load inertia during the divided rotation is reduced accordingly, and the indexing of the workpiece becomes faster and more accurate.

Therefore, according to this embodiment, during machining with a fixed blade, gears such as the drive side gear 55 and the C-axis motor 51 from the main shaft 2 are
Since the main shaft 2 is rotated by the spindle motor 3 via the spline connection between the rotary transmission shaft 4 and the main shaft 2, vibration and noise generation can be reduced during machining, and the main shaft 2 can rotate at high speed. In addition, when machining with a rotating blade, the main spindle 2 and spindle motor 3 are separated and the main spindle 2 is dividedly rotated only by the C-axis motor 51 to index the workpiece W, so that the load during rotation is reduced. Inertia is reduced, and the workpiece W can be indexed quickly and accurately.

(Effects of the Invention) As explained above, according to the present invention, when turning with a fixed knife, the indexing means is separated from the main spindle, and the main spindle is rotated by the continuous rotation driving means via the rotary transmission shaft. Large-diameter parts such as the drive gear do not rotate, reducing noise caused by vibration and wind noise, and the main shaft can be rotated at high speed.

In addition, when machining with a rotary blade, the main spindle and continuous rotation drive means are completely separated by the switching means, and the main spindle is rotated in parts by the indexing means to index the workpiece, so that the continuous rotation drive means is connected. The load inertia will be reduced to the extent that it has not been used, and high-speed and accurate indexing will be possible.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the overall configuration of an embodiment of an automatic lathe according to the present invention, FIG. FIG. 3 is a cross-sectional view showing a state of connection of main parts when the main shaft is dividedly rotated in the present device. 1... Headstock 2... Main spindle 3... Spindle motor (continuous rotation drive means) 4...
・Rotary transmission shaft 5... Indexing mechanism (indexing means) 6... Switching mechanism 11... Fixed cutter 12... Rotating cutter W... Work (switching means)

Claims (1)

[Claims] 1. A headstock of an automatic lathe that continuously rotates a workpiece and processes it with a fixed cutter, and also indexes the workpiece and processes it with a rotating cutter, comprising a rotation transmission shaft and a main shaft, and a workpiece mounted in these shafts. chucking means for inserting the rotary transmission shaft and the main shaft to chuck the tip of the workpiece; continuous rotation driving means for continuously rotating the rotary transmission shaft and the main shaft via a belt; switching means for connecting or disconnecting the rotary transmission shaft and the main shaft; A headstock for an automatic lathe, characterized in that the headstock of an automatic lathe is provided with indexing means for rotating the main shaft in parts and indexing a workpiece after the main shaft is separated from the rotation transmission shaft by a switching means.