JPH079297A - Rotary tool holder - Google Patents

Abstract

PURPOSE:To provide a rotary tool holder in which a rotary body for fitting a tool or an intermediate rotary body for supporting this rotary body via a bearing is retained by an unrotary retaining body via a bearing, in which infiltration of chips and working fluid is completely prevented, early stage wearing of the bearing is not caused, durability is excellent, and which is suitable for high speed rotary machining. CONSTITUTION:An intermediate rotary body 1 for supporting via a bearing 3a a tool fitting rotary body 2 whose one end side is adopted as a tool fitting part 2a is rotatably retained by an unrotary retaining body 4 via a bearing 3c, and air supply passages 11, 14a-14c, 16 are provided for introducing air into an inner space 15 of a fitting part for the bearings 3a, 3c. The air introduced into the inner space 15 is blown out to the outside through gaps g1-g3 of relatively rotating parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary tool holder in which a tool mounting rotary body or an intermediate rotary body supporting the rotary body via a bearing is rotatably held by a non-rotating holder via the bearing. , Particularly to the holder suitable for high-speed rotation processing.

[0002]

2. Description of the Related Art In this type of rotary tool holder, cutting chips scattered during machining and machining fluid such as coolant and cutting oil are used as a gap between relative rotary parts, that is, a rotary body for tool mounting serves as a non-rotary holder. In the case where it is held directly, it is inside the gap between them, and in the case where it has an intermediate rotating body such as a holder with a speed increasing mechanism, it is inside the gap between the intermediate rotating body, the non-rotating holding body and the tool mounting rotating body. There is a problem that it easily invades, the bearing is abraded early by the cutting chips being caught, and the lubricating oil of the bearing is invaded by the cutting oil to deteriorate the lubricating function.

Conventionally, in order to prevent the cutting chips and the working fluid from entering the bearing portion as described above, an O-ring or the like made of rubber or synthetic resin is provided at the gap inlet side of the relative rotating portion of the rotary tool holder. A means for fitting a sliding contact type sealing material has been widely adopted. However, in recent years, for example, a tool holder with a speed increasing mechanism has a tool rotation speed of 20,000.
Since the processing speed has been increasing, such as setting the number of times more than once, and at such high-speed processing, the sliding contact type seal material such as the O-ring cannot withstand frictional heat. A non-sliding contact type sealing material composed of a ring made of metal is used.

[0004]

However, in the above-mentioned non-sliding contact type seal material, the open ring-shaped metal ring externally fitted to the inner rotary body of the relative rotary part is centrifuged by the rotation of the inner member. The force expands the diameter and lifts it up from the groove, and in this lifted state it shields the gap of the relative rotating part from the outside, so it is suitable for high-speed rotation, but it is difficult to structurally complete sealing. There is. Therefore, in the rotary tool holder using such a non-sliding contact type seal material, it is not possible to reliably prevent the intrusion of cutting chips and machining liquid into the bearing portion, and shorten the service life due to early wear of the bearing. In addition, the gear having a speed-up mechanism may wear the gear due to the invading chips.

In view of the above situation, the present invention is a rotary tool in which a tool mounting rotary body or an intermediate rotary body supporting the rotary body via a bearing is rotatably held by a non-rotating holding body via the bearing. As a holder for bearings, it is possible to completely prevent invasion of cutting chips and machining liquid from the gap of the relative rotating part, and therefore, the bearing is not worn out at an early stage and has extremely excellent durability, and particularly suitable for high speed rotating machining. Is intended.

[0006]

In order to achieve the above object, a holder for a rotary tool according to claim 1 of the present invention is denoted by the reference numeral of a first embodiment shown in FIG. A tool mounting rotating body 2 having one end side as a tool mounting portion 2a or an intermediate rotating body 1 supporting the rotating body 2 through a bearing 3a.
Are rotatably held by the non-rotating holder 4 via bearings 3c and introduce air into the inner space 15 of the fitting portions of these bearings 3a, 3c.
And the air introduced into the inner space 15 has a gap g between the rotary members 1 and 2 and the non-rotational holding member 4 relative to each other.
_It employs a configuration in which it is spouted from _{1 to} g ₃ to the outside.

According to a second aspect of the present invention, in the rotary tool holder according to the first aspect, the air introduced into the inner space 15 of the fitting portion of the bearings 3a, 3c contains an oil mist. Is.

According to claim 3 of the present invention, the holder body 1
From the center hole 18 to the inner space 15 of the fitting portion of the bearing 3b.
Air is introduced into the tool mounting rotary body 2 corresponding to the center hole 18, and the air flow speed increasing mechanism 40 is integrally provided.

[0009]

During machining, the air introduced into the inner space of the fitting portion of the bearing passes through the bearing and is passed between the non-rotation holder and the tool mounting rotor or the intermediate rotor, or the tool mounting rotor. Since it spouts to the outside from the gap of the relative rotating part such as between the and the intermediate rotating body, cutting chips and machining liquid cannot enter these gaps,
Premature wear of the bearing due to the intrusion is prevented. However, by adopting such a means, the seal material mounted in the gap portion in the conventional rotary tool holder becomes completely unnecessary. In order to eject air from the gap, compressed air is introduced into the inner space from the air supply passage, or air is sucked into the rotary tool holder itself from the air supply passage and discharged from the gap. By providing the pump mechanism, the atmospheric pressure in the inner space of the bearing fitting portion may be set to be higher than the external atmospheric pressure (usually 1 atmospheric pressure).

Further, as described in the invention of claim 2, if an oil mist is mixed in such introduced air, the operating bearing will be constantly refueled by the passing air. As a result, the rotary tool holder has a longer life.

Further, according to the third aspect of the invention, the air introduced from the center hole 18 of the holder body 1 into the inner space of the fitting portion of the bearing accelerates its air flow by the speed increasing mechanism 40. Even in a narrow inner space, air can be circulated and ejected to the outside, whereby the intrusion of cutting chips can be reliably prevented.

[0012]

1 shows a rotary tool holder A with a speed increasing mechanism according to a first embodiment of the present invention. Reference numeral 1 in the figure denotes a cylindrical holder body that is an intermediate rotating body, and the front end side is a cylindrical portion 1
a, the rear end side forms a tapered shank portion 1b, and the intermediate portion is provided with a flange portion 1c for gripping a manipulator. Reference numeral 2 denotes a substantially round shaft-shaped tool mounting rotary body having a taper collet chuck type tool mounting portion 2a at its front end. The tool mounting portion 2a is inserted into the cylindrical portion 1a of the holder body 1 so as to project outward. , Which are rotatably held by the holder body 1 via four bearings 3a having the same diameter in the middle portion and a bearing 3b having a small diameter in the rear end portion. Reference numeral 4 denotes a short cylindrical non-rotating holder that is fitted onto the cylindrical portion 1a of the holder body 1 via bearings 3c and 3c.

Thus, the cylindrical portion 1a of the holder body 1 is formed with the side openings 6 between the innermost portion of the bearings 4a ... And the bearing 4b and at two to three circumferential positions. ,
Each pivot pin 7a fixed across each of these openings 6
The planetary gears 7 are rotatably attached to the respective bearings via bearings 3d and 3d. These planetary gears 7 mesh with a sun gear 8 fixed to the outer circumference of the tool mounting rotary body 2 and an internal gear 9 fixed to the inner circumference of the non-rotation holder 4.
As a result, a speed increasing mechanism that significantly increases the rotation of the holder body 1 and transmits it to the tool mounting rotary body 3 is configured. Further, a locking ring 10 having a locking recess 10a facing the front is externally fitted and fixed to the front side of the flange part 1c on the holder body 1, and a substantially L-shaped cross section is formed at the front end of the cylindrical part 1a. The front end ring member 1d is externally fitted and screwed, and an annular small gap g ₁ is formed between the inner circumference of the front end ring member 1d and the outer circumference of the non-rotation holder 4.

The non-rotation holding member 4 abuts on the bearings 3c, 3c at the front inner circumference having a small inner and outer diameter, and has a main ring member 4a fixed to the rear inner circumference with the internal gear 9 and a front outer circumference thereof. Screwed to the front end ring member 4b having a substantially L-shaped cross section
And a rear end ring member 4c having a substantially L-shaped cross section that is internally fitted to the rear end side of the main ring member 4a and fixed by screws. The inner circumferences of both ring members 4b and 4c and the holder body 1 are Small annular gaps g ₂ and g ₃ are formed between the outer periphery and the outer periphery, and the stopper pin 11 is held in a state of protruding rearward on the cylinder portion 4d protruding outward from the main ring member 4a in the radial direction. There is.

The stopper pin 11 includes an outer cylinder 11a slidably fitted in the cylinder portion 4d in a direction parallel to the holder body 1, and a check valve 12 screwed into the outer cylinder 11a so that the check valve 12 is provided inside the tip. And an inner cylinder 11b loaded with
A coil spring 11c mounted between the rear end of the outer cylinder 11a and the inner rear end of the cylinder portion 4a is biased in the rearward protruding direction. Further, the stopper pin 11 has
Lock nut 13a and outer cylinder 11 screwed into the inner cylinder 11b
The anti-rotation member 13 is fixed between the rear end face a and the tip of the anti-rotation member 13 protruding toward the axial center of the holder main body 1 when the rotary tool holder A is not used. The holder main body 1 and the non-rotational holding body 4 are engaged with each other so that they cannot rotate relative to each other by fitting into the locking recess 10a of the stop ring 10. 1
3b is fixed to the main ring member 4a to prevent the rotation preventing member 13
It is a guide pin that penetrates through.

On the other hand, an annular space 14a is formed between the inner periphery of the front ring member 4b on the rear end side and the outer periphery of the main ring member 4a in the non-rotation holder 4, and this annular space 14a is formed in the main ring member 4a. The inner space 15 of the fitting portion of the bearings 3c, 3c is provided through the bent passages 14b formed at a plurality of circumferential positions.
The through hole 14c that is communicated with the front ring member 4b and is communicated with the annular space 14a that is formed on the side of the front ring member 4b is communicated with the inner rear portion of the cylinder portion 5a through the pipe 16.
The inner space 15 is defined by the side opening 6 of the holder body 1.
At the rear side of the bearing 3b, a communication space is formed over the entire gear arrangement portion from the inner peripheral side of the non-rotational holding body 4 to the outer peripheral side of the tool mounting rotary body 2 through a gap around the planetary gear 7 in. Due to the circular shield plate 17 arranged, the shank portion 1b
The side center hole 18 is blocked.

In the rotary tool holder A having the above structure, when the shank portion 1b of the holder body 1 is fitted into the spindle S of the machine tool, the tip of the stopper pin 11 is the recess D of the fixed engaging portion F on the machine tool side. Cylinder part 4d
Is pushed into the non-rotational holder 4 and the anti-rotation member 13 is released from the locking recess 10a on the holder body 1 side.
Is held in a non-rotating state, and the holder body 1 becomes rotatable. Therefore, when the holder body 1 is rotated by driving the spindle S, the planetary gear 7 engages with the internal gear 9 of the non-rotating holder 4 to make several revolutions per revolution of the holder body 1, so that the tool mounting Rotating body 2 is holder body 1
Therefore, the tool can rotate at a speed several times faster, and a tool (not shown) mounted on the tool mounting portion 2a can perform high-speed machining.

Therefore, the fixed engagement portion F on the machine tool side is set so as to supply the compressed air to the concave portion D from the internal introduction passage H, and the supplied compressed air is supplied to the check valve 12.
When it is opened, it flows into the stopper pin 11, and from the cylinder portion 4c, the pipe 16, the through hole 14c, the annular space 14
a, through the meandering passage 14b into the inner space 15,
Bearing 3a ... and bearings 3c, through the 3c, than the small gap g ₂ between the small gap g ₁ and non-rotating support 4 between the front side and the tool mounting rotating body 2 of the cylindrical portion 1a of the holder body 1 In addition to ejecting to the outside of the front, it also ejects from the small gap g ₃ between the rear side of the cylindrical portion 1a and the non-rotational holding body 4 to the outside of the rear, so that the cutting chips and the working liquid being processed are in these small gaps g _{1 to} g _3.
Prevents further intrusion. If oil mist is mixed in the compressed air, each bearing 3
a and 3c are constantly supplied with oil in the compressed air passing therethrough, and the bearing 3b and the bearing 3d of the planetary gear 7 are also replenished with oil. The life is longer.

FIG. 2 shows a rotary tool holder B with a speed increasing mechanism according to a second embodiment of the present invention. In this holder B, the annular space 14a between the rear end side inner circumference of the front ring member 4b of the non-rotational holding body 4 and the outer circumference of the main ring member 4a does not communicate with other parts, and the annular space 14a Although there is no communication between 14a and the inside of the cylinder portion 4d, there is no circular shield plate 17 in the first embodiment, and there is a spiral around the outer periphery of the end of the tool mounting rotary body 2 corresponding to the center hole 18 of the holder body 1. An airflow speed increasing mechanism 40 such as a blade for a pump or a blade for an axial flow pump is integrally provided. FIG. 3 shows a structure in which an airflow speed increasing mechanism 40 including blades for a centrifugal pump is provided on the outer peripheral portion of the distal end portion of the tool mounting rotary body 2.

That is, the rotary tool wheel of the second embodiment is
In Ruder B, when mounted on the spindle S, the first
For increasing the rotation speed of the tool mounting rotor 2 as in the embodiment
Higher speed machining is possible, but the holder from the spindle S side
-The flow of air supplied from the center hole 18 of the main body 1
High-speed rotation of the airflow speed increasing mechanism 40 provided on the outer peripheral portion of the rotating body 2.
The pressure is increased due to the rotation to become compressed air, and the compressed air
The inner space 15 is passed through the bearing 3b, that is, the non-rotational holder 4
Arrangement of gears from the inner peripheral side to the outer peripheral side of the tool mounting rotor 2
Flows into the communication space over the entire part, and the bearings 3a ...
The cylindrical portion 1a of the holder body 1 passes through the receivers 3c, 3c.
Gap g between the front side of the tool and the tool mounting rotor 2₁And non-return
Small gap g with rolling holder 4₂When spouting out further forward
A small gap between the rear side of the cylindrical portion 1a and the non-rotational holding body 4.
g₃From the rear to the outside and cut in the same way as the first embodiment.
The powder or processing liquid has these small gaps.₁~ G₃Intrude more
Completely prevent it. Therefore, the compressed air supply
In the holder A for rotary tools of the first embodiment, the side through method is used.
In contrast to the formula, the holder for the rotary tool of the second embodiment
-B is a center-through type, and in this embodiment
The air supplied to the inside of the holder body 1 is compressed air.
Even if it is not, the air flow increase provided inside the holder body 1
The air becomes the air pressure increased and increased by the speed mechanism 40,
Gap g₁~ G ₃The jet output from can be increased. Shi
However, even in this second embodiment, the
It goes without saying that oil mist can be mixed in as in the above.
Yes.

FIG. 4 shows a rotary tool holder C according to a third embodiment of the present invention. In this holder C, a tool mounting rotary body 20 is provided at the lower portion of a box-shaped fixed casing 19 which is a non-rotating holder, and two pairs of front and rear bearings 21a, 21a and 21b,
21b is rotatably supported horizontally and is horizontally held in a state in which the front end side taper collet chuck type tool mounting portion 20a is projected outward, and in the casing 19 above this, it is vertically arranged above. Primary transmission shaft 22 of shaft center
A secondary transmission shaft 23 having a horizontal shaft center disposed in the middle is rotatably held via a pair of bearings 21c, 21c and 21d, 21d, respectively. Then, casing 1
The portion for holding the primary transmission shaft 22 constitutes a cylindrical portion 19a protruding upward, the upper end of the primary transmission shaft 22 is exposed at the opening 24 of the upper end surface thereof, and the cylindrical portion 19a has a cylindrical shape. The drive shaft cover 25 is closely fitted to the outside.

The primary transmission shaft 22 has a bevel gear 26 at its lower end.
The outer cylinder 22a provided with a and the outer periphery of the upper end are sawtooth-shaped engaging portions 27
The inner cylinder 22b, which is a, is key-engaged to both
It is fixed and integrated by a bolt 22c that is screwed onto the inner circumference extending over 2b. Further, the secondary transmission shaft 23 is provided with a bevel gear 26a that meshes with the bevel gear 26a of the primary transmission shaft 22 at the front end, and a spur gear 28a is fixed between the front and rear bearings 21d, 21d. It meshes with a spur gear 28b fixed in the middle of the body 20. A drive shaft 29 that can move forward and backward in the axial direction is arranged in the drive shaft cover 25, and the saw blade-shaped engaging portion 27 b at the tip of the drive shaft 29 is connected to the saw blade-shaped engaging portion of the primary transmission shaft 22. Two
When the drive shaft 29 is rotationally driven by meshing with 7a, this rotation is transmitted from the primary transmission shaft 22 to the tool mounting rotary body 20 through the secondary transmission shaft 23, and the tool mounting rotary body 20 is rotated.
The required processing is performed by the rotation of the rotary tool (not shown) attached to the tool mounting portion 20a.

In this case, however, it is set so that compressed air can be supplied from the machine body side through the drive shaft cover 25, and this compressed air flows into the casing 19 through the opening 24 and the bearings 21c, 21c. And bearing 21
d, 21d, and a gap 30 between the primary and secondary transmission shafts 22, 23 and the inner surface of the casing 19 to enter an inner space 31 between the bearings 21a, 21 and the bearings 21b, 21b of the tool mounting rotary body 20. , Further passes through the bearings 21a, 21, and a small annular gap g ₄ between the outer periphery of the tool mounting rotary body 20 on the front side and the ring-shaped end plate 19b of the casing 19.
It is designed to blow out more. Therefore, also in this rotary tool holder C, as in the case of the first and second embodiments, there is no intrusion of cutting chips or machining liquid into the interior from the small gap g ₄ during machining. It is needless to say that the oil mist can be mixed into the compressed air in the third embodiment as well.

The rotary tool holder of the present invention has a structure in which a tool mounting rotary body having one end side as a tool mounting portion is rotatably held by a non-rotating holder via a bearing, or Any structure may be used as long as the intermediate rotating body supported via the bearing is rotatably held by the non-rotating holding body via the bearing, and includes holders of various structures other than the first to fourth embodiments described above. . In addition, the arrangement of the air supply path that introduces air into the inner space of the fitting part of the bearing, the configuration of the pump mechanism etc. when the air is introduced by the holder side self-contained system, the gap configuration of the relative rotating part that should eject air, etc. With respect to the detailed configuration, various designs can be changed other than the embodiment.

[0025]

According to the first aspect of the present invention, the rotating body for tool mounting or the intermediate rotating body supporting the rotating body through the bearing is rotatably held by the non-rotating holder through the bearing. As a holder for tools, with an extremely simple structure,
It is possible to completely prevent intrusion of cutting chips and machining fluid from the gap of the relative rotating part, and thus the bearing is not prematurely worn and has excellent durability. Moreover, the seal mounted in the gap part in the conventional rotary tool holder. A material can be eliminated, and a material suitable for high-speed rotation processing can be provided.

According to the second aspect of the invention, as the holder for the rotary tool, there is provided a holder having excellent durability, particularly the bearing, and thus the entire holder.

According to the third aspect of the present invention, the air or compressed air introduced into the holder main body at atmospheric pressure or a pressure close to the atmospheric pressure is further increased in pressure by the air flow speed increasing mechanism. Therefore, it is not particularly necessary to introduce compressed air from the outside, and by further increasing the speed and pressure, it is possible to prevent cutting chips and machining fluid from entering the gap between the relative rotating parts more completely. It is possible to prevent early wear of the bearing.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a main part of a rotary tool holder according to a first embodiment of the present invention.

FIG. 2 is a semi-longitudinal side view of a rotary tool holder according to the second embodiment.

FIG. 3 is a perspective view showing a main part of the second embodiment.

FIG. 4 is a vertical sectional side view of a rotary tool holder according to the third embodiment.

[Explanation of symbols]

1 Holder Main Body (Intermediate Rotating Body) 2 Tool Mounting Rotating Body 2a Tool Mounting Part 3a Bearing 3c Bearing 4 Non-Rotating Holding Body 11 Stopper Pin (Air Supply Path) 14a Annular Space (Air Supply Path) 14b Bent Path (Air Supply Path) ) 14c Through hole (air supply path) 15 Inside space 16 Pipe (air supply path) 18 Center hole (air supply path) 19 Casing (non-rotation holding body) 20 Tool mounting rotor 20a Tool mounting part 21a Bearing 30 Gap ( Air supply path) 31 Inner space 40 Airflow speed increasing mechanism A to C Holder for rotary tool g _{1 to} g ₄ Small gap

Claims (3)

[Claims] 1. A tool mounting rotary body having one end as a tool mounting portion or an intermediate rotary body supporting the rotary body via a bearing is rotatably held by a non-rotating holder via a bearing. An air supply path for introducing air into the inner space of the fitting portion of the bearing is provided, and the air introduced into the inner space is ejected to the outside from the gap between the relative rotating portions of the two rotating bodies and the non-rotating holding body. A rotating tool holder that is composed. 2. The rotary tool holder according to claim 1, wherein the air introduced into the inner space of the fitting portion of the bearing contains oil mist. 3. The air is introduced from the center hole of the holder main body into the inner space of the fitting portion of the bearing, and the tool mounting rotary body corresponding to the center hole is integrally provided with an air flow speed increasing mechanism. The rotary tool holder described in 1 or 2.