JP2001353655A - Honing work tool, and working method using the tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize work from preparing work to honing work with a single tool. SOLUTION: This honing work tool 10 is provided with a tool main body 12 having a taper part 14 to be engaged with a taper hole formed in a rotary main shaft of a machine tool, a boring cutter for boring processing fixed to a tip part of the tool main body 12, plural honing sticks 28 provided in the circumferential direction in a tip part range of the tool main body 12 to be capable of advancing or retracting in radial directions of the tool main body 12, a coolant supply passage 12a to jet coolant supplied into the tool main body 12 through the rotary main shaft of the machine tool out of a coolant nozzle provided on a side surface of the tool main body 12, and a honing grinding wheel advancing and retracting means to advance/retract the honing grinding wheel 28 in the radial directions of the tool main body 12 by pressure of coolant supplied to the coolant supply passage 12a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a honing tool mounted on a rotating spindle of a machine tool for processing an inner surface of a cylindrical bore formed in a work, and a method of processing using the honing tool.

[0002]

2. Description of the Related Art Honing processing improves the processing accuracy of the roundness of the inner surface of an inner cylinder bore of a work machined by a precision boring machine, an inner surface grinding machine, or the like, and a surface called a so-called cross hatch is formed on the inner surface. It forms the shape. The honing tool used for the honing process includes a honing head that holds a plurality of square rod-shaped fine-grained grindstones so as to make surface or line contact with the inner surface of the inner cylinder bore of the work. By applying pressure and rotating the honing head in reciprocating motion in the axial direction in synchronization with the rotation, the inner surface of the inner bore of the work is machined. Therefore, one point on the contact surface of the grindstone draws an oblique line with respect to the workpiece surface, and the direction changes when the reciprocating movement direction of the honing head changes, and a cross hatch is drawn on the workpiece surface.

The first prior art is disclosed in Japanese Patent Laid-Open No. 2-106.
There is a honing head disclosed in Japanese Patent Publication No. 268. this is,
A honing tool mounted on a rotating spindle of a machine tool, by supplying a grinding wheel diameter expanding fluid to a honing head diameter expanding fluid passage by a through spindle method,
Due to the supply pressure of the fluid, the pressing shaft moves toward the tip of the honing head against the elastic bias of the spring, and the grinding wheel expands due to sliding contact between the tapered portion of the pressing shaft and the tapered portion of the grinding wheel holder. It is provided with a contact pressure on the inner surface of the cylindrical bore of the work.

[0004] As a second prior art, Japanese Utility Model Application Laid-open No.
There is a honing tool disclosed in the 117856 publication. This is a honing tool mounted on the rotating spindle of a machine tool. By supplying coolant to the oil path of the honing head by a through spindle method, the piston in the cylinder is resilient to the spring by the supply pressure of the coolant. The grindstone moves to the tip side of the honing head against the urging, and the diameter of the grindstone is expanded by the sliding contact between the tapered portion of the grindstone expanding cone at the tip of the piston and the tapered portion of the grindstone holder. Is applied to the contact pressure.

[0005]

In order to perform honing, it is necessary to perform preprocessing for forming a pilot hole such as an inner surface of a cylindrical bore in a work in advance. Since the pre-processing requires relatively high-precision processing, it is generally performed by a machine tool such as a precision boring machine or an internal grinding machine. However, when pre-processing is performed with a machine tool such as a precision boring machine or an internal grinding machine, the pre-processed work is removed and the setup work is re-attached to a dedicated honing machine for honing. Has to be performed, and there is a problem that the processing efficiency is deteriorated.

The first and second prior arts disclose a technique for performing honing using a honing tool mounted on a rotating spindle of a machine tool such as a machining center. In this case, after pre-processing the inner surface of the cylindrical bore of the work with the pre-processing tool, the pre-processing tool is replaced with a honing tool by using an automatic tool changer. It can be performed. There is an advantage that pre-processing to honing can be performed on a single machine tool from work preparation to honing without work setup. However, in addition to the honing tool, a cutter for pre-processing and a grinding tool are further required, increasing costs. There is a problem that also leads to.

An object of the present invention is to solve such a problem of the prior art, and a honing tool capable of performing from pre-processing to honing with a single tool, and machining using the tool. It is intended to provide a way.

[0008]

According to a first aspect of the present invention, there is provided a honing tool mounted on a rotating spindle of a machine tool for machining an inner surface of a cylindrical bore formed in a workpiece. A tool body having a tapered portion that engages with a tapered hole formed in the tool body, a boring cutter fixed to a tip portion of the tool body, and a plurality of circumferentially extending portions in a tip portion region of the tool body. A honing grindstone that is provided and is capable of moving back and forth in the radial direction of the tool body; and a coolant that is supplied to the inside of the tool body via a rotating spindle of the machine tool is ejected from a coolant nozzle provided on a side surface of the tool body. A coolant supply passage, and a honing grinder for moving the honing grindstone back and forth in the radial direction of the tool body by the pressure of the coolant supplied to the coolant supply passage. The honing tool, characterized by comprising a moving means for the gist.

According to a second aspect of the present invention, there is provided a honing tool mounted on a rotating spindle of a machine tool for machining an inner surface of a cylindrical bore formed in a workpiece, wherein the tapered hole is formed in the rotating spindle of the machine tool. A tool body having a tapered portion to be engaged with, an electrodeposition grindstone for grinding fixed to a tip portion region of the tool body, a plurality of circumferentially provided in a tip portion region of the tool body, A honing grindstone capable of moving back and forth in the radial direction of the tool body, and a coolant supply passage for ejecting coolant supplied to the inside of the tool body via a rotating spindle of the machine tool from a coolant nozzle provided on a side surface of the tool body. And a honing grindstone advance / retreat means for moving the honing grindstone in the radial direction of the tool body by the pressure of the coolant supplied to the coolant supply passage. The honing tool, characterized by comprising the gist.

The honing grindstone advance / retreat means includes a pressure chamber formed in the tool body and communicating with the coolant supply passage, first and second pistons provided in the pressure chamber, and the first and second pistons. First and second taper cones that move in the axial direction of the tool body in response to a piston, and the honing grindstone is attached to a radially outer end face, and engages with the taper surfaces of the first and second taper cones. A honing grindstone holder that moves in the radial direction of the tool body according to the axial position of the first and second taper cones, and a return spring that biases the honing grindstone holder radially inward of the tool body. It can be configured to have.

According to a fourth aspect of the present invention, there is provided a machining method for machining an inner surface of a cylindrical bore formed in a work, wherein a boring cutter fixed to a tip end of a tool body and a radial direction of the tool body are provided. A honing tool configured with a honing grindstone that can move forward and backward is mounted on the rotating spindle of the machine tool, and the inner surface of the cylindrical bore formed in the work is bored by the boring cutter. The honing grindstone is advanced in the radial direction of the tool main body by the pressure of the coolant supplied to the inside of the tool main body through the rotary spindle of the machine tool, and the inner surface of the cylindrical bore after the boring of the work is honed. The gist of the present invention is a processing method characterized by the following.

According to a fifth aspect of the present invention, there is provided a machining method for machining an inner surface of a cylindrical bore formed in a work, comprising: an electrodeposited grinding wheel fixed to a tip end region of a tool body; A honing tool having a honing grindstone capable of moving back and forth in the radial direction is mounted on a rotating spindle of a machine tool, and the inner surface of the cylindrical bore formed in the workpiece is ground by the electrodeposition grindstone for grinding. Then, the honing grindstone is advanced in the radial direction of the tool body by the pressure of a coolant supplied to the inside of the tool body via the rotating spindle of the machine tool, and the inner surface of the cylindrical bore after the grinding of the workpiece is honed. The gist is a processing method characterized by processing.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
A preferred embodiment of the present invention will be described. An example of a machine tool to which the honing tool of the present invention is mounted will be described with reference to FIG. The machining center 200 includes a bed 201 serving as a base of the machine, and a column 20 that moves along a guide 203 provided in the rear of the bed 201 in the X-axis direction.
5, a table 209 for moving the workpiece W along the guide 207 provided in the front of the bed 201 in the Z-axis direction and placing the work W, and a guide 211 provided in the front of the column 205 in the Y-axis direction. Along with a spindle head 215 having a spindle 213 to which a tool is attached at the tip.

Here, the column 205 moves in the X-axis direction, the spindle head 215 moves in the Y-axis direction, and the table 209 moves in the Z-axis direction. However, the shaft configuration of the machine tool on which the honing tool of the present invention is mounted is described. Is not limited to this.

FIG. 7 shows a case where a honing tool 10 according to a first embodiment described later is mounted on a main shaft 213. A tapered hole 213 a that engages with the tapered portion 14 of the honing tool 10 is formed at the tip of the main shaft 213. A coolant passage 213b communicating with the coolant passage 12a of the honing tool 10 is formed inside the main shaft 213, and the coolant supplied from the coolant supply source 52 receives the coolant passage 213b of the main shaft 213 and the honing tool Of the workpiece W through the coolant passage 12a.

Here, the case where the so-called through spindle coolant system is adopted has been described. However, the machine tool on which the honing tool of the present invention is mounted is not limited to this system.
That is, it goes without saying that a configuration in which the coolant is directly supplied to the coolant passage 12a inside the tool without passing through the inside of the main shaft 213 may be adopted.

As described above, in the machine tool to which the honing tool of the present invention is mounted, the honing tool 10 as in the first embodiment described later, that is, the tapered portion 14 engaging with the tapered hole 213a formed in the main shaft 213. A honing head 12 having a horn, a plurality of honing grindstones 28 provided in the circumferential direction in the distal end region of the honing head 12 and capable of moving back and forth in the radial direction, and a pre-processing tool fixed to the distal end of the honing head 12. By using the honing tool 10 having a certain cutter 40,
On one machine tool, a single tool can perform from pre-processing to honing of the bore Wb formed in the workpiece W.

Honing tool 10 according to the first embodiment
Includes a cylindrical honing head 12 and a honing head holder 16 rotatably connected to the honing head 12 via a bearing 16c. At the rear end of the honing head 12, a tapered hole 213a at the tip of the main shaft 213 of the machining center 200 as shown in FIG.
The honing head 12 is provided at its tip with a cutter 40 for precision boring as a pre-processing tool. In FIG. 1, the cutter 40 comprises a throw-away tip and a holder for holding the throw-away tip, but it goes without saying that another cutter for precision boring may be used.

FIG. 5 shows the machining center 2 shown in FIG.
00 is a main part configuration block diagram. A machining center 200 for using the honing tool 10 according to the present embodiment includes a spindle 2 rotatably supported by a spindle head 215.
13, a table 209 for fixing the work W in a face-to-face state with respect to the main shaft 213, and feed motors Mx and M for relatively moving the main shaft 213 and the work W in X, Y, and Z axis directions orthogonal to each other.
NC for controlling y, Mz and feed motors Mx, My, Mz
The device 44 includes, as main components, a machine control device 46 that controls a spindle motor Ms that rotationally drives the spindle 213. The machining center 200 further includes a coolant supply source 52 for supplying a coolant to the honing tool 10, and a pneumatic source 48 for supplying pressurized air for detecting a processing state described later in a pneumatic manner.

The honing head 12 has a coolant passage 12a formed along the center axis thereof. The coolant passage 12a is a coolant pressure passage for supplying pressure for biasing a grindstone, which will be described later, to the inner surface of a bore Wb (see FIG. 5) formed in the work W near the center along the central axis of the honing head 12. 12b and a coolant branch passage 12c for supplying coolant to the machining area toward the inner surface of the bore Wb. The coolant pressure passage 12b communicates with a pressure chamber 21 described below, the coolant branch passage 12c communicates with a coolant nozzle 38a provided on the outer surface of the honing head 12, and the coolant nozzle 38a is formed on the nozzle plate 38. I have. In the present embodiment, a coolant supply passage is formed by the coolant passage 12a and the coolant branch passage 12c. Coolant nozzle 3 on nozzle plate 38
Since the nozzle plate 8a is formed, a plurality of types of nozzle plates provided with coolant nozzles having various diameters are prepared, and the nozzle plates are appropriately replaced, so that an optimum coolant nozzle can be selected according to processing conditions.

The honing head 12 further has a first central bore 12e formed along its central axis. First and second pistons 18 and 19 are provided above the center bore 12e so as to be movable in the axial direction.
The second piston 19 has a center hole 19a and is formed in a ring shape, and is disposed more distally than the first piston 18. The first piston 18 is provided with a connecting rod 1 extending from the lower surface thereof along the central axis of the honing head 12.
8a. First and second pistons 18, 19
As shown in FIG. 1, the pressure chambers 21 are axially spaced apart from each other in the first center bore 12e, and a pressure chamber 21 communicating with the coolant pressure passage 12b is defined therebetween.

The honing head 12 further has a second center bore 12f formed on the tip side from the first center bore 12e, and the inner diameter of the second center bore 12f is equal to the first center bore. It is larger than the inner diameter of 12e. As will be described later, first and second tapered cones 20 and 22 formed in a truncated cone shape are provided in the second center bore 12f as driving members for driving the grindstone in the radial direction. The first and second tapered cones 20, 22 have tapered surfaces 20a, 22a, and are disposed such that the respective tapered surfaces 20a, 22a face each other in the second central bore 12f. The first taper cone 20 is
It has a central hole 20b penetrating and formed along its central axis. The connecting rod 18a of the first piston 18 is
The first piston 18 and the second taper cone 22 are integrally moved in the axial direction by extending through the center hole 20b of the taper cone 20 and the tip thereof is connected to the second taper cone 22. . Also, a seat 20 is provided at the tip of the small diameter of each of the first and second tapered cones 20, 22.
c, 22b are provided, and a compression coil spring 24 is disposed between the seats 20c, 22b around the connecting rod 18a. The compression coil spring 24 urges the first and second tapered cones 20, 22 in a direction away from each other.

On the outer peripheral surface of the honing head 12, three recesses 30 are formed at regular intervals in the circumferential direction as a grindstone holder accommodating portion.
6 is disposed so as to be movable in the radial direction. The honing grindstone holder 26 has a pair of legs 26 extending radially inward.
a, the pair of legs 26a are axially separated from each other, and a tapered surface 26b is formed at a tip end thereof. Leg 26a of honing wheel holder 26
Extends into the second central bore 12f from an opening 30a formed in the radial direction between the recess 30 and the second central bore 12f, and has a tapered surface 26b formed by the first and second tapered cones 20. , 22 are slidably in contact with the tapered surfaces 20a, 22b.

On the outer surface of the honing grindstone holder 26, a columnar honing grindstone 28 is mounted. Further, a honing grindstone 28 is provided on the outer peripheral surface of the honing head 12.
In addition, two return springs 34 are provided to bias the honing wheel holder 26 radially inward. More specifically, although the honing grindstone 28 is divided into three parts so that the return spring 34 escapes between the three, the contact of the return spring 34 with the inner surface of the bore Wb is prevented.
Treated as two honing stones. Further, as shown in FIG. 1, a circumferential groove may be formed in the honing grindstone holder 26 so that the return spring 34 can further escape radially inward.

The honing head holder 16 has a joint 16a for coupling to a stationary portion such as the spindle head 215.
And a bore 16b through which the honing head 12 passes. A bearing 16c for rotatably supporting the honing head 12 is disposed in the bore 16b.
A peripheral groove 16d is formed on the inner peripheral surface of the bore 16b.
Inside the honing head holder 16, the joint 1
An air passage 16e is formed from 6a to the circumferential groove 16d. On the other hand, inside the honing head 12, three air passages 12g are bored in the axial direction.
2g at one end is a honing head holder 16
Communicates with the air passage 16e through the peripheral groove 16d, and communicates with the air nozzle 36 at the other end.

Hereinafter, the operation of the present embodiment will be described. Prior to the start of the honing process, the honing tool 10 is attached to the main shaft 213 by fitting the tapered portion 14 of the honing tool 10 into the tapered hole 213a of the main shaft 213 of the machining center 200. At this time, the joint 16a of the honing head holder 16 is
And a corresponding joint (not shown) provided on the spindle head 215 and other stationary parts. When the honing tool 10 is attached to the main shaft 213, the coolant supply source 52 supplies the coolant to the coolant passage 213 provided along the central axis of the main shaft 213.
b, communicating with the coolant passage 12a of the honing head 12 via a coolant joint 39 provided at the rear end of the honing head 12. At the same time, the air pressure source 48 is connected to the air passage 48 a and the air passage 1 of the honing head holder 16.
6e, and communicates with the air passage 12g of the honing head 12 via the circumferential groove 16d.

The work W is fixed to a table 209 provided opposite the honing tool 10. At this time, a bore Wb as a prepared hole is already formed in the work W by pre-processing. When the work W is fixed to the table 209,
The machining center 200 starts precision boring by the cutter 40 as a pre-processing step. That is, according to a machining command from the machine control device 46, the spindle motor Ms
Starts rotating at a predetermined rotation speed, and the feed motors Mx, My, and Mz relatively move the spindle head 215 and the work W according to a movement command from the NC device 44, and the center axis of the spindle 213 and the bore of the work W are moved. Match the center axis of Wb,
The main shaft 213 and the workpiece W are relatively moved in the Z-axis direction. At this time, based on a first pressure command from the machine control device 46, the coolant supply source 52
The coolant is supplied to the coolant passage 2 of the main shaft 213 at a pressure of
13b. The first pressure can be appropriately determined in a pressure range in which the honing wheel holder 26 does not advance outward in the radial direction in consideration of the spring force of the return spring 34 and the spring force of the coil spring 24. The machine control device 46 includes:
Furthermore, a pneumatic supply command is issued to the pneumatic source
The air pressure in the air passage 48a is monitored by the pressure gauge 50 provided at the position a. The processing status can be monitored by the change in the air pressure.

Thus, the cutter 4 of the honing tool 10
When 0 engages with the workpiece W, precision boring is actually started. At this time, the coolant is supplied from the coolant supply source 52 to the coolant conduit 52 a, the rotary joint 217 at the rear end of the spindle 213, and the coolant passage 2 of the spindle 213.
13b, the coolant joint 39, the coolant passage 12a of the honing tool 10, and the coolant nozzle 38a ejects the coolant to the inner surface of the bore Wb. As described above, the supply pressure of the coolant at this time does not advance from the recess 30 due to the spring force of the return spring 34 while securing the pressure necessary for precision boring. Alternatively, the pressure is such that the honing grindstone 28 does not come into contact with the inner surface of the bore Wb even if it advances. In other words, the return spring 34 is selected so as to exert a spring force necessary to prevent the honing grindstone holder 26 from going out of the recess 30 while securing the pressure necessary for precision boring.

During the precision boring, air of a predetermined pressure is supplied from the air pressure source 48 to the air nozzle 48 through the air passage 48a, the air passage 16e of the honing head holder 16, the circumferential groove 16d, and the air passage 12g of the honing head 12. From 36, it is ejected toward the inner surface of the bore Wb as a precision prepared hole subjected to precision boring. During this time, the machine control device 46
The air pressure in the air passage 48a is continuously monitored by the pressure gauge 50. The pressure in the air passage 48a is based on the original pressure supplied by the air pressure source 48, the air passage 48a, the air passage 16e of the honing head holder 16, the circumferential groove 16d, and the air supply passage formed by the air passage 12g of the honing head 12. It is affected by the pressure loss in the pipe and the nozzle loss of the air nozzle 36. Further, the nozzle loss of the air nozzle 36 may be affected by the influence of the distance between the air nozzle 36 and the inner surface of the bore Wb, particularly when the air nozzle 36 is disposed close to the inner surface of the bore Wb. Affected by the inner surface properties of

For example, while the precision boring is started and the honing tool 10 enters the bore Wb of the workpiece W,
When the air nozzle 36 is hidden in the bore Wb, the air passage 48
When the pressure in the air passage 48a increases stepwise and the precision boring progresses and the cutter 40 emerges from the opposite side of the workpiece W, the pressure in the air passage 48a decreases stepwise. In particular, when the cutting edge of the cutter 40 is worn, the cutting amount is reduced and the diameter of the bore Wb formed by precision boring is reduced, so that the pressure in the air passage 48a is increased. The machine control device 46 monitors the pressure in the air passage 48a with the pressure gauge 50 to determine when to replace the cutter 40. That is, when the pressure in the air passage 48a during the precision boring operation becomes higher than the predetermined pressure, the machine control device 46 gives an indication of tool change to the operator.

When the precision boring as pre-processing is performed on the inner surface of the bore Wb of the workpiece W as described above,
Without pulling out the honing tool 10 from the bore Wb,
Subsequently, honing processing is started on the inner surface of the bore Wb. That is, the Z-axis coordinate of the main shaft 213 is transmitted from the NC device 44 to the machine control device 46 every moment, and the Z-axis coordinate of the main shaft 213 becomes a predetermined value and becomes the cutter 40.
Is determined to have penetrated the workpiece W, the machine control device 4
6 issues a command to the NC device 44 to start a honing processing program, and rotates the spindle motor Ms at a predetermined rotation speed suitable for honing processing. The machine controller 46 also issues a command to the coolant supply source 52 to supply coolant at a predetermined second pressure. The second pressure is higher than the first pressure, and as described later, the honing grindstone holder 26 is advanced radially outward from the recess 30 to remove the honing grindstone 2.
8 is a pressure that can be pressed against the inner surface of the bore Wb with a predetermined pressing force.

The coolant supply source 52 supplies the coolant to the coolant passage 1 of the honing head 12 at the second pressure.
2a, the coolant W from the coolant nozzle 38a
The coolant is jetted toward the inner surface of the piston b, and the pressure is transmitted to the pressure chamber 21 through the coolant pressure passage 12b, and urges the first and second pistons 18 and 19 away from each other. As a result, the first and second tapered cones 20, 22 perform an approaching operation to each other. When the first and second tapered cones 20 and 22 move closer to each other, the honing grindstone is engaged through the engagement between the respective tapered surfaces 20a and 22a and the tapered surface 26b formed on the leg 26a of the honing grindstone holder 26. The holder 26 is pushed radially outward from the recess 30 and pressed against the inner surface of the bore Wb. In this state, the main shaft 213 is caused to reciprocate in the Z-axis direction while rotating, and the two are synchronized to form the bore Wb.
The inner surface is honed. Since the inner surface of the bore Wb of the work W is ground as the honing process progresses, the pressure in the air passage 48a gradually decreases. When the pressure in the air passage 48a reaches a predetermined value, the machine control device 46 determines that honing has been completed, moves the spindle 213 upward (to the right in FIG. 7), and causes the honing tool 10 to move the work W
Pulled out of.

According to this embodiment, the honing tool 10
However, since it is equipped with the cutter 40 for precision boring and the honing grindstone 28 provided so as to be able to advance and retreat in the radial direction, it is possible to perform the operations from precision boring to honing without changing tools. Become. Further, according to the honing process 10 of the present embodiment, air of a predetermined pressure is supplied from the pneumatic source 48 to the air passage 48 a and the honing head holder 1.
6, air passage 16e, circumferential groove 16d, honing head 1
The air is blown from the air nozzle 36 into the bore Wb of the work W toward the inner peripheral surface through the second air passage 12g, and the air passage 48a
Since the honing processing is performed while constantly monitoring the internal pressure, the honing processing can be performed even in a general-purpose machine such as a machining center. At this time, general-purpose machines such as machining centers have a minimum number of auxiliary machines, that is, a coolant supply source capable of supplying coolant with the first and second coolant pressures, a control device therefor, and a pneumatic system that provides air pressure to the inner surface of the bore. The honing method according to the present embodiment can be implemented by providing a control device that determines a machining state based on changes in the pressure source and the air pressure and controls the machining process.

Next, a honing tool 100 according to a second embodiment of the present invention will be described with reference to FIG. In FIG. 6, a honing tool 1 according to a second embodiment of the present invention is shown.
00, like the first embodiment, includes a column-shaped honing head 102 and a honing head holder 106 rotatably connected to the honing head 12 via a bearing (not shown). At the rear end of the honing head 102, the main shaft 2 of the machining center 200 is mounted.
13 (see FIG. 6) is provided with a tapered portion 104 that fits into the tapered hole 213a at the tip. Also in the present embodiment, the machining center 200 for using the honing tool 100 can be configured substantially in the same manner as in FIG. 7, and the main components are as shown in FIG.

The honing tool 10 according to the first embodiment
In the above, a cutter 40 for precision boring was fixed to the honing head 12 as a pre-processing tool.
In the pre-processing tool of the honing tool 100 according to the embodiment, an inner surface grinding wheel 112 for grinding the inner surface of the bore Wb formed in the work W is provided. Further, the grinding wheel 112 for inner surface grinding can be preferably a so-called electrodeposition grinding wheel in which a CBN abrasive grain or a diamond abrasive grain is firmly bonded to a base material, whereby the main shaft 213 is advanced only once in the axial direction. It is possible to complete the internal grinding process by operating.

Other configurations are the same as those of the first embodiment. FIG. 5 shows a honing grindstone 110 for honing work fixed to a honing grindstone holder 108 provided to be able to advance and retreat in the radial direction. Coolant nozzle 11
Nozzle plate 114 with 4a, air nozzle 11
6, the return spring 118 is shown.

Hereinafter, the operation of the present embodiment will be described. Second
Prior to the start of the honing process according to the embodiment, the tapered portion 104 of the honing tool 100 is fitted into the tapered hole 213a of the main shaft 213 of the machining center 200, and the honing tool 100 is attached to the main shaft 213 (see FIG. 5). The honing tool 100 first starts internal grinding of the bore Wb by the internal grinding wheel 112 as preprocessing. That is, the spindle motor Ms starts rotating at a predetermined rotation speed according to a machining command from the machine control device 46, and the feed motors Mx, My, and Mz move the spindle 213 and the workpiece W according to a movement command from the NC device 44. The main shaft 213 is moved relatively to make the center axis of the main shaft 213 coincide with the center axis of the bore Wb of the workpiece W.
And the workpiece W are relatively moved in the axial direction. At this time, the coolant supply source 52 supplies the coolant at a predetermined first pressure based on a first pressure command from the machine control device 46. The first pressure can be appropriately determined in a pressure range in which the honing grindstone holder 108 does not advance outward in the radial direction in consideration of the spring force of the return spring 118. The machine control device 46 further issues a pneumatic supply command to the pneumatic source 48, and the pressure gauge 5 provided in the air passage 48a.
By 0, the air pressure in the air passage 48a is monitored.

Thus, the inner surface grinding by the inner surface grinding wheel 112 as the pre-processing is started. At this time, as in the first embodiment, the coolant flows from the coolant supply source 52 through the inside of the main shaft 213 and the inside of the honing head 102, and is jetted from the coolant nozzle 114a to the inner surface of the bore Wb. As described above, the supply pressure of the coolant at this time is adjusted in accordance with the spring force of the return spring 118 and the coil spring 24 while securing the supply amount of the coolant necessary for the inner surface grinding, so that the honing grindstone holder 108 is moved in the radial direction. Or the pressure at which the honing grindstone 110 does not come into contact with the inner surface of the bore Wb.

During the internal grinding, air of a predetermined pressure from the pneumatic source 48 flows through the inside of the honing head holder 106 and the inside of the honing head 102, and the air nozzle 1
16 to the bore W of the workpiece W on which the internal grinding is performed
It is ejected toward the inner surface of b. During this time, the machine control device 4
6, the pressure gauge 50 continues to monitor the air pressure in the air passage 48a. When the grinding wheel 112 for inner surface grinding is worn or the grinding wheel is clogged, the cutting amount decreases. Therefore, when the inner surface grinding wheel 112 is in such a state, the main shaft 213
The diameter of the inner surface formed by the inner surface grinding by one forward movement of the above becomes smaller, and the pressure in the air passage 48a increases. The machine controller 46 controls the air passage 4 by the pressure gauge 50.
8a, the internal grinding wheel 1 is monitored.
Twelve replacement times are determined. That is, the machine control device 4
Reference numeral 6 indicates to the operator an indication of tool change when the pressure in the air passage 48a during the inner surface grinding processing becomes higher than a predetermined pressure.

When the inner surface of the bore Wb of the workpiece W is ground as described above and the pre-processing step is completed, the honing processing is started without pulling out the honing tool 100 from the bore Wb, and the machine control unit 46 sets the NC. A command is issued to the device 44 to start a honing process program, and the spindle motor Ms is rotated at a predetermined rotation speed suitable for the honing process. Machine control unit 46
Also issues a command to the coolant supply source 52 to supply coolant at a predetermined second pressure. The second pressure is a pressure higher than the first pressure, as in the first embodiment, and causes the honing grindstone 110 to advance radially outward to the inner surface of the bore Wb on which the inner surface grinding has been performed. This is the pressure that can be pressed.

When the coolant supply source 52 supplies the coolant at the second pressure, the honing wheel holder 108
Is pushed radially outward from the recess of the honing head 12, and the honing grindstone 110 is pressed against the inner surface of the bore Wb on which the inner surface grinding has been performed. In this state, the spindle 21
3 is reciprocated in the Z-axis direction while rotating, and the inner surface of the bore Wb is honed. Bore Wb of workpiece W with progress of honing
Is ground, the pressure in the air passage 48a gradually decreases. When the pressure in the air passage 48a reaches a predetermined value,
The machine control device 46 determines completion of the honing processing, moves the main shaft 213 upward (to the right in FIG. 7), and the honing tool 100 is pulled out of the workpiece W.

According to this embodiment, the honing tool 10
0 is provided with a grinding wheel 112 for internal grinding fixed to the honing head 12 and a honing grindstone 110 provided to be able to advance and retreat in the radial direction, so that the tool is not changed from the internal grinding to the honing. It is possible to do. In addition, the honing tool 10 according to the present embodiment
The first is that honing can be performed with general-purpose machine tools such as machining centers with minimal modification.
This is the same as the embodiment.

[0043]

According to the present invention, since the honing tool includes the pre-processing tool and the honing grindstone provided so as to be able to advance and retreat in the radial direction, it can be used for precision boring, internal grinding, and the like. It is possible to perform from pre-processing to honing without changing tools. Also, when shifting from the pre-processing step to the honing step, machining is performed without pulling out the honing tool from the cylindrical bore of the work, so that the roundness of the inner surface of the cylindrical bore that has been subjected to honing is significantly higher precision. be able to.

Further, there is provided machining status monitoring means for monitoring a machining status by a change in pressure in an air supply path for supplying the air to the honing head from an air pressure source for supplying air at a predetermined pressure to the honing head. Therefore, honing can be performed even on a general-purpose machine tool such as a machining center.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a honing tool according to a first embodiment of the present invention.

FIG. 2 is a side view of the honing tool of FIG. 1;

FIG. 3 is a sectional view taken along line III-III of FIG.

FIG. 4 is a view taken in the direction of arrows IV-IV in FIG. 1;

FIG. 5 is a block diagram of a main part configuration of the machine tool of FIG. 7;

FIG. 6 is a side view of a honing tool according to a second embodiment of the present invention.

FIG. 7 is a side view of a machine tool on which the honing tool of the present invention is mounted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Honing tool 12 ... Honing head 14 ... Taper part 16 ... Honing head holder 20 ... Second taper cone 21 ... Pressure chamber 22 ... First taper cone 26 ... Honing grindstone holder 28 ... Honing grindstone 34 ... Return spring 40 ... Boring Machining cutter 209 Table 213 Main spindle 100 Honing tool 102 Honing head 104 Tapered portion 106 Honing head holder 108 Honing grindstone holder 110 Honing grindstone 112 Internal grindstone 116 Air nozzle 36 Air nozzle 114a ... Coolant nozzle 38a ... Coolant nozzle 16e ... Air passage 16d ... Peripheral groove 12g ... Air passage 12a ... Coolant passage 200 ... Machining center W ... Work Wb ... Bore

Claims (5)

[Claims] 1. A honing tool mounted on a rotating spindle of a machine tool for machining an inner surface of a cylindrical bore formed in a workpiece, the honing tool having a tapered portion engaging with a tapered hole formed in the rotating spindle of the machine tool. A tool body, a boring cutter fixed to the tip of the tool body, a plurality of cutters provided in the circumferential direction in a tip region of the tool body,
A honing grindstone capable of moving back and forth in the radial direction of the tool body, and a coolant supply for jetting coolant supplied to the inside of the tool body via a rotating spindle of the machine tool from a coolant nozzle provided on a side surface of the tool body. A honing tool comprising: a passage; and a honing grindstone advance / retreat means for causing the honing grindstone to advance / retreat in a radial direction of the tool main body by a pressure of the coolant supplied to the coolant supply passage. 2. A honing tool mounted on a rotating spindle of a machine tool for machining an inner surface of a cylindrical bore formed in a workpiece, the honing tool having a tapered portion engaging with a tapered hole formed on the rotating spindle of the machine tool. A tool body, and an electrodeposited grinding wheel for grinding fixed to a tip region of the tool body, a plurality of circumferentially provided in a tip region of the tool body,
A honing grindstone capable of moving back and forth in the radial direction of the tool body, and a coolant supply for jetting coolant supplied to the inside of the tool body via a rotating spindle of the machine tool from a coolant nozzle provided on a side surface of the tool body. A honing tool comprising: a passage; and a honing grindstone advance / retreat means for causing the honing grindstone to advance / retreat in a radial direction of the tool main body by a pressure of the coolant supplied to the coolant supply passage. 3. The honing grindstone advance / retreat means includes a pressure chamber formed in the tool body and communicating with the coolant supply passage; first and second pistons provided in the pressure chamber; First and second taper cones that move in the axial direction of the tool body in response to the second piston, and the honing grindstone is attached to a radially outer end face and engages with the taper surfaces of the first and second taper cones. A honing grindstone holder that moves in the radial direction of the tool body in accordance with the axial position of the first and second taper cones; and a return spring that biases the honing grindstone holder radially inward of the tool body. The honing tool according to claim 1 or 2, comprising: 4. A machining method for machining an inner surface of a cylindrical bore formed in a work, comprising: a boring cutter fixed to a tip portion of a tool body; and a honing grindstone capable of moving forward and backward in a radial direction of the tool body. A honing tool configured to be mounted is mounted on a rotating spindle of a machine tool, and the inner surface of a cylindrical bore formed in the workpiece is bored by the boring cutter, via a rotating spindle of the machine tool. A machining method characterized in that the honing grindstone is advanced in a radial direction of the tool body by the pressure of a coolant supplied to the inside of the tool body, and the inner surface of the cylindrical bore after the boring of the workpiece is honed. . 5. A machining method for machining an inner surface of a cylindrical bore formed in a workpiece, comprising: an electrodeposited grinding wheel fixed to a tip end region of a tool body for grinding; and a honing grindstone capable of moving back and forth in a radial direction of the tool body. Mounting a honing working tool comprising a rotating spindle of a machine tool, grinding an inner surface of a cylindrical bore formed in the work by the electrodeposition grindstone for grinding, and a rotating spindle of the machine tool. A machining operation in which the honing grindstone is advanced in the radial direction of the tool body by the pressure of a coolant supplied to the inside of the tool body via the tool body, and the inner surface of the cylindrical bore after the grinding of the workpiece is honed. Method.