JP2022001392A - Machine tool - Google Patents

Abstract

To make it less likely to break down in a machine tool having a cutting tool for cutting a circular work-piece.SOLUTION: A machine tool 1 comprises a main spindle 3, and a cutting tool 5. The main spindle 3 has a holding part 7 which holds a circular work-piece W and is rotatable around an axis O1. The cutting tool 5 is located on a front side of the main spindle 3, and rotates around a rotation center O2 crossing the axis O1 of the main spindle 3. The cutting tool 5 has a blade part 11. The blade part 11 is located so that a cut part of the circular work-piece W is positioned on a circulating locus C of the blade part 11 when the cutting tool 5 rotates around the rotation center O2.SELECTED DRAWING: Figure 3

Description

The present invention relates to a machine tool, and more particularly to a machine tool having a cutting tool for cutting a circular workpiece.

In a conventional machine tool, a chamfering tool is moved in the axial direction by moving a machining axis up and down in a vertical lathe, and a gearwork is chamfered.
Further, Patent Document 1 discloses a technique in which the bite 6 reciprocates to chamfer as a method for grinding the end of the cylindrical work 2.

Japanese Unexamined Patent Publication No. 8-294801

In the above-mentioned machine tool, the ball screw of the machining shaft is liable to break down due to the fine ascending / descending motion (reciprocating motion) of the machining shaft.

An object of the present invention is to make it difficult for a failure to occur in a machine tool having a cutting tool for cutting a circular workpiece.

Hereinafter, a plurality of aspects will be described as means for solving the problem. These aspects can be arbitrarily combined as needed.

The machine tool according to the apparent aspect of the present invention includes a spindle and a cutting tool.
The spindle has a holding portion that holds the circular workpiece and can rotate around the axis.
The cutting tool is located on the front side of the spindle and rotates around a center of rotation that intersects the axis of the spindle.
The cutting tool has a blade portion.
The blade portion is arranged so that the cut portion of the circular workpiece is positioned on the circumferential locus of the blade portion when the cutting tool rotates around the center of rotation.
In this machine tool, the cutting tool rotates to cut the machined portion of the circular workpiece. As described above, unlike the conventional machine tool, the machine tool is less likely to break down because there is no raising / lowering operation of the machining shaft.

The circular workpiece may have an inner peripheral gear or an outer peripheral gear.
The blade portion has a bifurcated shape and may cut both sides in the circumferential direction of either one of the inner peripheral gear and the outer peripheral gear when moving on the circumferential locus.
In this machine tool, both sides in the circumferential direction of one tooth are cut by one cutting operation, so that the machining efficiency is good.

When the blade moves on the circumferential locus, it cuts both sides of the tooth in the circumferential direction of either the inner gear or the outer gear at the same time, and at the same time, cuts one side of the tooth in the circumferential direction on both sides of the tooth. May be good.
In this machine tool, since both sides of one tooth in the circumferential direction and one side of the tooth in the circumferential direction of the tooth are cut by one cutting operation, the machining efficiency is good.

The blade portion may be cut by passing through the workpiece portion of the circular workpiece when the spindle is stopped rotating.
In this machine tool, since the circular workpiece is stopped, the cutting tool can accurately cut the machined portion of the circular workpiece.

For the spindle, the holding portion may be rotated by a predetermined angle around the axis between the machining of the circular workpiece by the cutting tool and the next machining.
In this machine tool, before the cutting tool cuts the circular work, the position of the machined portion of the circular work is changed in the rotational direction from the position at the time of the previous cutting by the holding portion. Therefore, the cutting process is continuously executed along the circumferential direction of the circular workpiece.

The orbital locus of the blade includes the first rotation position before the blade machined the machined portion of the circular workpiece and the second rotation position after the blade machined the machined portion of the circular workpiece. May be good.
The blade portion rotates from the first rotation position to the second rotation position along the orbital locus to cut the machined portion of the circular workpiece in the middle of the rotation, and the first rotation from the second rotation position along the orbital locus. By rotating to the position in the same rotation direction as the cutting operation, the machined portion may be in a state where it can be cut next after the rotation.
In this machine tool, the cutting tool blade can be cut by rotating from the first rotation position to the second rotation position to perform cutting, and then rotating from the second rotation position to the first rotation position. Become a state. Since the cutting tool has the same rotation direction in all rotation operations, the overall rotation operation becomes smooth.

The rotation of the blade portion from the second rotation position to the first rotation position may be faster than the rotation of the blade portion from the first rotation position to the second rotation position.
In this machine tool, the time from the end of cutting to the next state in which cutting is possible is shortened.

The machine tool may further include a tool drive mechanism for rotating the cutting tool.

Since the machine tool according to the present invention does not raise and lower the machining shaft, it is unlikely to break down.

The schematic perspective view of the machine tool which concerns on 1st Embodiment. Schematic front view of a machine tool. Sectional drawing which shows the cutting process by a machine tool schematically. Partially enlarged view of FIG. Schematic partial plan view showing cutting by a machine tool. Schematic partial plan view showing cutting by a machine tool. A block diagram showing a control configuration of a machine tool. A flowchart showing a machine tool cutting control operation. The cross-sectional view which shows typically the cutting process by the machine tool which concerns on 2nd Embodiment.

1. 1. First Embodiment (1) Basic Configuration The machine tool 1 will be described with reference to FIGS. 1 to 6. FIG. 1 is a schematic perspective view of a machine tool according to the first embodiment. FIG. 2 is a schematic front view of a machine tool. FIG. 3 is a cross-sectional view schematically showing a cutting process by a machine tool. FIG. 4 is a partially enlarged view of FIG. 5 and 6 are schematic partial plan views showing cutting by a machine tool.

The machine tool 1 is a device for chamfering a circular work W. The chamfering process chamfers the tooth profile ridge, which is the corner between the end face and the tooth surface in the work.

The circular work W is a gear work having an inner peripheral gear 21 and an outer peripheral gear 23. Specifically, the machine tool 1 chamfers the inner peripheral gear 21 of the circular work W. In the following description, when the individual teeth of the inner peripheral gear 21 are described, the teeth 21A are used.
More specifically, as shown in FIGS. 3 and 4, the circular work W has a tubular portion 25 and a flange portion 27, and the inner peripheral gear 21 is formed on the inner peripheral surface of the tubular portion 25. It is a spline gear, and the outer peripheral gear 23 is formed on the outer peripheral surface of the flange portion 27.

The machine tool 1 includes a spindle 3 and a cutting tool 5.
The spindle 3 is a work rotating device that rotates the circular work W. The spindle 3 has a holding portion 7. The holding portion 7 holds the circular work W and can rotate around the axis O1. Specifically, the holding portion 7 is a chuck mechanism that holds the outer peripheral surface (the end portion on the opposite side of the flange portion 27) of the cylindrical portion 25 of the circular work W.

The cutting tool 5 is arranged on the front side of the spindle 3 and rotates around a rotation center O2 that intersects the axis O1 of the spindle 3. Specifically, the machine tool 1 further includes a tool drive mechanism 9 for rotating the cutting tool 5. Specifically, the tool drive mechanism 9 is a mechanism provided on a general lathe for cutting a work by a rotary tool (drill, end mill), and is a drive shaft provided perpendicular to the tool drive shaft and supporting the cutting tool 5. It has a shaft, a transmission mechanism that transmits and connects the two, a motor that rotates the tool drive shaft, and the like.
The cutting tool 5 has a blade portion 11. As shown in FIGS. 5 and 6, the blade portion 11 has a bifurcated shape.

As shown in FIG. 3, when the cutting tool 5 rotates around the rotation center O2, the blade portion 11 has a machined portion W1 (inner peripheral gear 21) of the circular work W on the circumferential locus C of the blade portion 11. It is arranged so that (partly described later) is located. In the first embodiment, the cutting tool 5 rotates clockwise in FIG.
Specifically, the orbital locus C of the blade portion 11 is a first rotation position C1 before the blade portion 11 processes the machined portion W1 of the circular work W, and the blade portion 11 is a machined portion W1 of the circular work W. It includes the second rotation position C2 after processing.

In this machine tool 1, the cutting tool 5 rotates, so that the blade portion 11 cuts the machined portion W1 of the circular work W. As described above, unlike the conventional machine tool 1, the machine tool 1 is less likely to break down because there is no raising / lowering operation of the machining shaft.

(2) Control Configuration The control configuration of the machine tool 1 will be described with reference to FIG. 7. FIG. 7 is a block diagram showing a control configuration of a machine tool. The machine tool 1 has a controller 51.
The controller 51 is a computer having a processor (for example, a CPU), a storage device (for example, ROM, RAM, HDD, SSD, etc.) and various interfaces (for example, an A / D converter, a D / A converter, a communication interface, etc.). It is a system. The controller 51 performs various control operations by executing a program stored in the storage unit (corresponding to a part or all of the storage area of the storage device).

The controller 51 may be composed of a single processor, or may be composed of a plurality of independent processors for each control.
A part or all of the functions of each element of the controller 51 may be realized as a program that can be executed by the computer system constituting the control unit. In addition, a part of the function of each element of the control unit may be configured by a custom IC.
The controller 51 is connected to the spindle 3 and the tool drive mechanism 9, and can specifically drive those motors.
Although not shown, the controller 51 is connected to a sensor that detects the size, shape, and position of the circular work W, a sensor and a switch for detecting the state of each device, and an information input device.

(3) Cutting operation The cutting operation control operation will be described with reference to FIG. FIG. 8 is a flowchart showing a machine tool cutting control operation.

(3-1) Approximate operation The blade portion 11 of the cutting tool 5 rotates from the first rotation position C1 to the second rotation position C2 to cut the circular work W. After that, the holding portion 7 rotates the circular work W by a predetermined angle, so that the position of the portion to be cut W1 next to the circular work W is arranged on the circumferential locus C of the blade portion 11. By repeating the above operation, the cutting process is continuously executed along the circumferential direction of the circular work W. That is, the circular work W is intermittently rotated by a predetermined angle (an angle corresponding to one pitch), and the machined portion W1 is cut by the blade portion 11 of the cutting tool 5 when the rotation is stopped.

(3-2) Detailed operation The control flowchart described below is an example, and each step can be omitted or replaced as necessary. Further, a plurality of steps may be executed at the same time, or some or all of them may be executed in an overlapping manner.
Further, each block of the control flowchart is not limited to a single control operation, and can be replaced with a plurality of control operations represented by a plurality of blocks.
The operation of each device is the result of a command from the control unit to each device, and these are represented by each step of the software application.

In step S1, it is determined whether or not all the teeth 21A of the inner peripheral gear 21 of the circular work W have been chamfered. Specifically, the controller 51 executes the above determination. If everything is chamfered, the process is complete. If there is a tooth 21A that has not been chamfered, the process proceeds to step S2.

In step S2, the blade portion 11 moves along the circumferential locus C in the same rotation direction as the cutting operation, that is, rotates from the second rotation position C2 (post-machining position) to the first rotation position C1 (pre-machining position). .. As a result, the blade portion 11 is in a state where the cut portion W1 of the circular work W can be cut next. Specifically, the controller 51 controls the tool drive mechanism 9 to execute the above operation. As described above, since the cutting tool 5 has the same rotation direction in any of the rotation operations, the entire rotation operation becomes smooth.
In the rotation from the second rotation position C2 to the first rotation position C1, the blade portion 11 accelerates and decelerates from the stopped state to the stopped state. The rotation angle from the second rotation position C2 to the first rotation position C1 is, for example, 270 degrees.

In step S3, as shown in FIGS. 5 and 6, the holding portion 7 rotates the circular work W around the axis O1 by a predetermined angle. As a result, the next cut portion W1 of the circular work W is located on the circumferential locus C of the blade portion 11. In this way, the spindle 3 moves the next machined portion W1 of the circular work W to the machining position between the machining of the circular workpiece W by the cutting tool 5 and the next machining. Specifically, the controller 51 controls the spindle 3 to execute the above operation.
It should be noted that step S3 may be executed at the same time as or in duplicate with step S2, or may be executed before step S2.

In step S4, the blade portion 11 rotates from the first rotation position C1 (pre-machining position) to the second rotation position C2 (post-machining position) along the circumferential locus C, so that the machined portion W1 of the circular work W is cut. To cut. Specifically, the controller 51 controls the tool drive mechanism 9 to execute the above operation.
In the rotation from the first rotation position C1 to the second rotation position C2, the blade portion 11 accelerates and decelerates from the stopped state to the stopped state. The rotation angle from the first rotation position C1 to the second rotation position C2 is, for example, 90 degrees.

In the above cutting operation (step S4), when the blade portion 11 passes through the cut portion W1 of the circular work W and cuts, the spindle 3 is stopped rotating. Therefore, the cutting tool 5 can accurately cut the machined portion W1 of the circular workpiece W.
The machined portion W1 will be specifically described. In the above cutting operation (step S4), the blade portion 11 cuts both sides of the tooth 21A of any one of the inner peripheral gears 21 in the circumferential direction when moving on the circumferential locus C. Further, when the blade portion 11 moves on the circumferential locus C, the inner peripheral gear 21 cuts one side of the teeth 21A on both sides in the circumferential direction at the same time as the above-mentioned teeth 21A. In this machine tool 1, one cutting operation of the cutting tool 5 cuts both sides of one tooth 21A in the circumferential direction and one side of the tooth 21A on both sides in the circumferential direction, so that the machining efficiency is good.

The rotation of the blade portion 11 from the second rotation position C2 to the first rotation position C1 in the above-mentioned cutting preparation operation (step S2) is larger than the rotation of the blade portion 11 from the first rotation position C1 to the second rotation position C2. It's fast. Therefore, the time from the end of cutting to the state where the next cutting is possible is shortened.

2. 2. 2nd Embodiment In the 1st embodiment, the inner peripheral gear of the circular work is chamfered, but the outer peripheral gear may be chamfered.
Such an embodiment will be described as a second embodiment with reference to FIG. FIG. 9 is a cross-sectional view schematically showing the cutting process by the machine tool according to the second embodiment.

Since the basic structure and operation of the second embodiment are the same as those of the first embodiment, the differences will be mainly described.
The circular work W is a gear work having an inner peripheral gear 21 and an outer peripheral gear 23. Specifically, the machine tool 1 chamfers the outer peripheral gear 23 of the circular work W.

The blade portion 11 is arranged so that when the cutting tool 5 rotates around the rotation center O2, the cut portion W1 (a part of the outer peripheral gear 23) of the circular work W is positioned on the circumferential locus C of the blade portion 11. , Have been placed. In the second embodiment, the cutting tool 5 rotates counterclockwise in FIG.
Specifically, the orbital locus C of the blade portion 11 is a first rotation position C1 before the blade portion 11 processes the machined portion W1 of the circular work W, and the blade portion 11 is a machined portion W1 of the circular work W. It includes the second rotation position C2 after processing.

In this machine tool 1, the cutting tool 5 rotates to cut the machined portion W1 of the circular work W. As described above, unlike the conventional machine tool 1, the machine tool 1 is less likely to break down because there is no raising / lowering operation of the machining shaft.
The blade portion 11 of the cutting tool 5 rotates from the first rotation position C1 to the second rotation position C2 to cut the circular work W. After that, the holding portion 7 rotates the circular work W by a predetermined angle to arrange the position of the next cut portion W1 of the circular work W on the circumferential locus C of the blade portion 11. By repeating the above operation, the cutting process is continuously executed along the circumferential direction of the circular work W. That is, the circular work W is intermittently rotated by a predetermined angle (an angle corresponding to one pitch), and the machined portion W1 is cut by the blade portion 11 of the cutting tool 5 when the rotation is stopped.

More specifically, the blade portion 11 moves along the circumferential locus C in the same rotation direction as the cutting operation, that is, from the second rotation position C2 (post-machining position) to the first rotation position C1 (pre-machining position). Rotate. As a result, the blade portion 11 is in a state where the cut portion W1 of the circular work W can be cut next. As described above, since the cutting tool 5 has the same rotation direction in any of the rotation operations, the entire rotation operation becomes smooth.

Next, the holding portion 7 rotates the circular work W around the axis O1 by a predetermined angle. As a result, the portion W1 to be cut next to the circular workpiece W is located on the circumferential locus C of the blade portion 11. In this way, the spindle 3 moves the next machined portion W1 of the circular work W to the machining position between the machining of the circular workpiece W by the cutting tool 5 and the next machining.

Next, the blade portion 11 rotates from the first rotation position C1 (pre-machining position) to the second rotation position C2 (post-machining position) along the circumferential locus C, so that the cut portion W1 of the circular work W is moved. To cut.
In the above cutting operation, when the blade portion 11 passes through the cut portion W1 of the circular work W and cuts, the spindle 3 is stopped rotating. Therefore, the cutting tool 5 can accurately cut the machined portion W1 of the circular workpiece W.

3. 3. Common items of the embodiment The following points are common to the first embodiment and the second embodiment.
The machine tool (for example, machine tool 1) includes a spindle and a cutting tool.
The spindle (for example, the spindle 3) holds a circular work (for example, the circular work W) and has a holding portion (for example, a holding portion 7) that can rotate around the axis (for example, the axis O1). There is.
The cutting tool (for example, the cutting tool 5) is arranged on the front side of the spindle and rotates around the center of rotation (for example, the center of rotation O2) intersecting the axis of the spindle.
The cutting tool has a blade portion (for example, the blade portion 11).
The blade portion is arranged so that the cut portion (for example, the cut portion W1) of the circular workpiece is positioned on the orbital locus (for example, the orbital locus C) of the blade portion when the cutting tool rotates around the center of rotation. , Have been placed.
In this machine tool, the cutting tool rotates to cut the machined portion of the circular workpiece. As described above, unlike the conventional machine tool, the machine tool is less likely to break down because there is no raising / lowering operation of the machining shaft.

4. Other Embodiments Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the invention. In particular, the plurality of embodiments and modifications described herein can be arbitrarily combined as needed.
The present invention is also applicable to a device for removing burrs and excess meat.
The shape and type of the circular work are not particularly limited. The circular work does not have to be a gear.

The shape of the cutting tool blade is not limited. The shape of the blade does not have to be bifurcated.
The cutting tool blade may cut only on both sides of one tooth in the circumferential direction. Alternatively, the blade may process more teeth at once than in the embodiment.

The angular positional relationship between the first rotation position and the second rotation position of the blade portion is not particularly limited.
Since it is only necessary to realize the timing at which the blade can be cut after positioning the circular workpiece, it is not necessary to stop at the first rotation position or the second rotation position, and the blade portion moves from the first rotation position to the second rotation position and the second rotation position. The speed of movement from the two rotation positions to the first rotation position may be the same.

The present invention can be widely applied to a machine tool having a cutting tool for cutting a circular workpiece.

1: Machine tool 3: Main shaft 5: Cutting tool 7: Holding part 9: Tool drive mechanism 11: Blade part 21: Inner peripheral gear 21A: Teeth 23: Outer peripheral gear 51: Controller C: Circumferential locus C1: First rotation position C2 : Second rotation position O1: Axial center O2: Rotation center W: Circular work

Claims (8)

A spindle that holds a circular workpiece and has a rotating retainer around the axis,
A cutting tool, which is arranged on the front side of the spindle and rotates around a rotation center intersecting the axis of the spindle, is provided.
The cutting tool has a blade portion and has a blade portion.
The blade portion is arranged so that the cut portion of the circular workpiece is positioned on the circumferential locus of the blade portion when the cutting tool rotates around the rotation center.
Machine Tools. The circular work has an inner peripheral gear or an outer peripheral gear, and has an inner peripheral gear or an outer peripheral gear.
The first aspect of claim 1, wherein the blade portion has a bifurcated shape and cuts both sides in the circumferential direction of any one of the inner peripheral gear and the outer peripheral gear when moving on the circumferential locus. Machine Tools. When the blade portion moves on the circumferential locus, the blade portion is simultaneously on both sides in the circumferential direction of either one of the inner peripheral gear or the outer peripheral gear, and at the same time on both sides in the circumferential direction of the tooth, one side in the circumferential direction of the tooth. 2. The machine tool according to claim 2. The machine tool according to any one of claims 1 to 3, wherein the blade portion passes through the machined portion of the circular work and cuts when the spindle is stopped rotating. The machine tool according to claim 4, wherein the spindle rotates the holding portion by a predetermined angle around the axis between the machining of the circular workpiece by the cutting tool and the next machining. The orbital locus of the blade portion is a first rotation position before the blade portion processes the machined portion of the circular work, and a first rotation position after the blade portion processes the machined portion of the circular work. Includes 2 rotation positions
The blade portion rotates from the first rotation position to the second rotation position along the orbital locus to cut the cut portion of the circular work, and the second rotation position is along the orbital locus. The machine tool according to claim 4, wherein the machine tool is rotated to the first rotation position in the same rotation direction as the cutting operation, so that the machined portion can be cut next. The sixth aspect of claim 6, wherein the rotation of the blade portion from the second rotation position to the first rotation position is faster than the rotation of the blade portion from the first rotation position to the second rotation position. Machine Tools. The machine tool according to any one of claims 1 to 7, further comprising a tool drive mechanism for rotating the cutting tool.

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