JPH06262481A - Boring work device - Google Patents

Abstract

PURPOSE:To improve machining accuracy by preventing a spindle from its thermal displacement due to heat generated from a rotor of a built-in motor, in a boring work device in which the built-in motor is used for driving the spindle rotated. CONSTITUTION:A coolant supply clearance 14 is formed of an insertion hole 5a formed in a spindle 5 and the periphery of an operating shaft 11, in a position corresponding to a rotor 9 of a built-in motor 10. One end of this coolant supply clearance 14 is connected to one end of the first supply passage 25 drilled in the operating shaft 11, the other end of the first supply passage 25 is connected to a coolant nozzle 24 drilled in a quill 6 to open toward the point end of a tool 16, the other end of the coolant supply clearance 14 is connected to one end of the second supply passage drilled in the operating shaft 11, and the other end of this second supply passage is connected to a coolant supplier set up in the outside of a spindle head 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boring machine for boring a workpiece.

[0002]

2. Description of the Related Art A conventional boring machine has a spindle head that moves back and forth relative to a workpiece, a spindle rotatably supported by the spindle head, and a quill fixed to the tip of the spindle. An operating shaft that is slidably inserted in the axial direction with relative rotation restricted in the main shaft and the quill, an advance / retreat drive device that advances / retreats this operating shaft according to the machining hole diameter of the workpiece, and the quill front part. A tool provided so as to be movable in the radial direction of the quill by advancing and retracting the operating shaft, and a rotary drive device for rotationally driving the main shaft.

Here, as a rotary drive device for rotationally driving a main spindle, conventionally, in order to cope with high-speed cutting, a rotor fixed to the outer circumference of the main spindle and fixed to the inner circumference of the main spindle head are arranged opposite to the outer peripheral surface of the rotor. There is one in which a main shaft is rotationally driven by a built-in motor composed of a stator.

[0004]

As described above, when the built-in motor is used to drive the main shaft to rotate, the main shaft is thermally displaced by the heat generated by the rotor of the built-in motor, which causes a problem that machining accuracy is deteriorated. .

[0005]

The boring machine of the present invention has been made to solve the above-mentioned problems, and is provided with a spindle head that moves back and forth relative to a workpiece, and the spindle head is provided with this spindle head. Is rotatably supported, a quill is fixed to the tip of the main spindle, the relative rotation is restricted between the main spindle and the quill, and the working shaft is slidably inserted in the axial direction. An advancing / retreating drive device for advancing / retreating according to a diameter is provided, and a tool is provided in the front portion of the quill so as to be movable in the radial direction of the quill by advancing / retreating of the operating shaft. In a boring machine configured to rotationally drive the spindle by a built-in motor that is fixed to the circumference and is arranged to face the outer peripheral surface of the rotor, the spindle is positioned at a position corresponding to the rotor. A coolant supply gap is formed between the formed insertion hole and the outer periphery of the working shaft, and one end of the coolant supply gap is connected to one end of a first supply passage bored in the working shaft. The other end of the coolant is connected to a coolant nozzle bored in the quill and opening toward the tip of the tool, and the other end of the coolant feed gap is connected to one end of a second feed passage bored in the operating shaft. Then this second
The other end of the supply passage is connected to a coolant supply device installed outside the spindle head.

[0006]

With the above construction, when machining a workpiece, first, the spindle is driven to rotate by the built-in motor, the spindle head is advanced with respect to the workpiece, and the quill is inserted into the machining hole of the workpiece. Next, the tool is moved in the radial direction of the quill by the advancing / retreating drive device via the actuating shaft. In this state, the spindle head is moved backward and a predetermined hole is drilled in the work. During machining, the coolant from the coolant supply device is reliably supplied from the coolant nozzle to the tool tip and the workpiece machining surface through the second supply passage, the coolant supply gap, and the first supply passage. Here, before the coolant is supplied from the coolant supply device to the coolant nozzle,
Since it passes through the coolant supply gap formed by the insertion hole formed in the main shaft at the position corresponding to the rotor and the outer periphery of the operating shaft, heat generated from the rotor of the built-in motor is absorbed.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, reference numeral 1 denotes a fixed base, on which a table 2 is slidably guided and supported. The table 2 is driven forward and backward by a table driving motor 3 provided on the fixed base 1.

As shown in FIG. 1, a spindle head 4 is fixed to the front portion of the table 2, and a spindle 5 is rotatable in the spindle head 4 around an axis parallel to the sliding direction of the table 2. Is supported by. At the tip of this spindle 5, the spindle 5
A quill 6 is fixed coaxially with. Further, a cylindrical rotor 8 made of a conductor is fitted and fixed to the outer periphery of the central portion of the main shaft 5 via an insulating member 7, and a minute gap is provided on the outer periphery of the rotor 8 on the inner periphery of the main spindle head 4. The stator 9 arranged so as to face each other is fixed, and the rotor 8 and the stator 9 are fixed.
The built-in motor 10 is constituted by and, and the main shaft 5 is driven to rotate together with the quill 6 by the built-in motor 10.

An actuating shaft 11 is restricted in relative rotation in the main shaft 5 and the quill 6, and an insertion hole 5a is formed in the main shaft 5.
Is supported via bushes 12 and 13 so as to be slidable in the rotation axis direction of the main shaft. A coolant supply gap 14 is formed at a position corresponding to the rotor 8 by the outer periphery of the operating shaft 11, the insertion hole 5a, and the end faces of the bushes 12, 13. Working shaft 11 corresponding to this coolant supply gap 14
A plurality of annular recessed grooves 11a are formed on the outer periphery of the shaft so as to be separated from each other in the axial direction, and the annular recessed grooves 11a absorb the vibration of the operating shaft 11 generated in the coolant supply gap 14 by the high speed rotation of the main shaft 5. The O-rings 15 that are members are fitted in each. Further, a plurality of cutout portions 11b are formed on the outer periphery of the operating shaft 11 in which the annular groove 11a is located so that the coolant can pass through the inner periphery of the O-ring 15.

At the tip of the quill 6, one end is fixed to the quill 6, the other end is provided with a tool 16, and the other end is provided with a tool holder 17 which is elastically displaceable in the radial direction of the quill 6. A taper 11c is formed at the tip of the operating shaft 11, and a tool 16 provided on the tool holder 17 is quilled via a movable pin 18 or the like provided so as to be movable in the radial direction of the quill 6 by advancing and retracting the taper 11c. 6 is displaced by the elasticity of the holder 17 in the radial direction.

As shown in FIG. 2, the rear end of the operating shaft 11 is supported by a bracket 20 via a bearing 19 so as to be relatively rotatable and immovable in the axial direction. A nut 22 screwed to a feed screw 21 is fixed to the bracket 20, and the feed screw 21 is rotationally driven by a rotary motor 23. As described above, the advancing / retreating drive device of the operating shaft 11 is configured, and when the feed screw 21 is rotated by the rotary motor 23, the bracket 20 fixed to the nut 22 advances and retreats, and the operating shaft 11 moves through the bearing 19. It is designed to be moved back and forth.

A coolant nozzle 24 having one end opening toward the tip of the tool 16 is bored in the quill 6, and the other end of the coolant nozzle 24 is a first supply passage 25 bored in the operating shaft 11. Is connected to one end of. The other end of the first supply passage 25 has the coolant supply gap 14
Is connected to one end of. The other end of the coolant supply gap 14 communicates with one end of a second supply passage 26 that is formed in the operating shaft 11 by penetrating the rear end portion of the operating shaft 11. A distributor 27 is connected to the other end of the second supply passage 26, and is connected to a coolant supply device 28 installed outside the spindle head 4 via the distributor 27.

Next, the operation of the above configuration will be described. When a workpiece (not shown) is fixed to a jig base (not shown) such that the processed hole is coaxial with the quill 6, the built-in motor 10 drives the spindle 5 to rotate, and the table driving motor 3 operates to move the spindle head 4 forward. Then, the quill 6 is inserted into the processed hole of the work. Next, the rotary motor 23 is operated to retract the operating shaft 11 by a predetermined amount, and the tool 16 is moved to a predetermined processing position. In this state, the spindle head 4 is retracted by the operation of the table drive device 3, and a predetermined hole is drilled in the work. During processing, the coolant from the coolant supply device 28 is distributed to the tip of the tool 16 by the distributor 27 and the second supply passage 2.
6, the coolant is supplied from the coolant nozzle 24 through the coolant supply gap 14 and the first supply passage 25.

Here, before the coolant is supplied from the coolant supply device 28 to the coolant nozzle 24, the main shaft 5 is located at a position corresponding to the rotor 9 of the built-in motor 10.
Since the coolant is passed through the coolant supply gap 14 formed by the insertion hole 5a formed in the above and the outer periphery of the operating shaft 11, the coolant cools the heat generated from the rotor 8 of the built-in motor 10 and the tool 16. It also serves to remove cutting heat and chips by supplying axial center coolant to the tip and work surface. As a result, thermal displacement of the spindle 5 can be prevented,
This has the effect of improving processing accuracy.

[0015]

According to the boring machine of the present invention, a coolant supply gap is formed by the through hole formed in the main shaft at the position corresponding to the rotor of the built-in motor and the outer periphery of the operating shaft. One end is connected to one end of a first supply passage that is bored in the operating shaft, and the other end of the first supply passage is connected to a coolant nozzle that is bored in the quill and opens toward the tip of the tool. The other end of the second supply passage is connected to one end of a second supply passage formed in the operating shaft, and the other end of the second supply passage is connected to a coolant supply device installed outside the spindle head. Absorbs heat generated from the rotor of the built-in motor when passing through the coolant supply gap, prevents thermal deformation of the spindle, and improves machining accuracy.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a front portion of a boring machine which is an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of the rear portion of the boring machine which is an embodiment of the present invention.

[Explanation of symbols]

 4 main spindle head 5 main spindle 5a insertion hole 6 quill 8 rotor 9 stator 10 built-in motor 11 working shaft 14 coolant supply gap 16 tool 19 bearing 20 bracket 21 feed screw 22 nut 23 rotary motor 24 coolant nozzle 25 first supply passage 26 second 2 Supply passage 28 Coolant supply device

Claims (1)

[Claims] 1. A spindle head which moves back and forth relative to a work is provided, a spindle is rotatably supported on the spindle head, and a quill is fixed to the tip of the spindle so that relative rotation is achieved between the spindle and the quill. A forward / backward drive device is provided which is regulated and slidably inserted in the axial direction, and which moves forward / backward according to the machining hole diameter of the workpiece. The spindle is provided movably in the radial direction of the quill, and the spindle is fixed by a built-in motor including a rotor fixed to the outer circumference of the spindle and a stator fixed to the inner circumference of the spindle head and arranged to face the outer circumferential surface of the rotor. In the boring machine adapted to be rotationally driven, a coolant supply gap is formed between the insertion hole formed in the main shaft and the outer periphery of the working shaft at a position corresponding to the rotor,
One end of the coolant supply gap is connected to one end of a first supply passage bored in the operation shaft, and the other end of the first supply passage is bored in the quill and opened toward the tip of the tool. The coolant is connected to a nozzle, the other end of the coolant supply gap is connected to one end of a second supply passage bored in the operating shaft, and the other end of the second supply passage is installed outside the spindle head. A boring machine that is connected to a supply device.