JP2538333B2 - Gear cutting machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a gear cutting machine, and in particular, when machining a Magariba bevel gear, both a crown gear and a bevel gear can be used as a virtual gear, which is high speed and small in size. The present invention relates to a gear cutting machine that can be made easier and has excellent workability.

[Conventional technology]

Conventionally, in the case of machining a magnifying glass gear, the machining is performed by a cutter attached to a gear machining machine representing a part of an imaginary gear that is commonly meshed with the small gear and the large gear. When the annular milling cutter is used, the relationship is conceptually represented as shown in FIG.

There are cases where a crown gear (a bevel gear with a cone angle of 90 °) is used as a virtual gear and a case where a bevel gear is used. The relationship with the large and small gears at that time is shown in Fig. 6 (in the case of a crown gear) and It is as shown in FIG. 7 (in the case of a bevel gear).

Figure 8 (in the case of crown gear) and 9 (in the case of bevel gear) are two-dimensionally showing the positional relationship between the machine and the cutter in that case.
It is as follows.

In FIGS. 8 and 9, the cutter 40 is held by a rotating body that rotates on the central axis 42 of the virtual gear 41.

The cutter shaft 43 that holds the cutter inside the rotating body is set parallel to the virtual gear center axis by a distance E or is separated by a certain distance.
Can be set at an angle θ with respect to. This changes depending on the virtual gear used.

In this way, the cutter 40 is rotated (thin arrow) for cutting, and the center axis 45 of the workpiece 44 and the center axis 42 of the virtual gear 41, which are indicated by the thick arrows, are set to the ratio of the number of teeth. A predetermined gear can be processed by rotating with. With regard to these basic types, techniques such as Japanese Patent Publication No. 30-3900 are known.

[Problems to be Solved by the Invention]

In the above-mentioned known technique, there are the following problems when machining a magaly beaker gear.

(A) It is difficult to increase the speed because the rotating body that holds the cutter and represents the virtual gear becomes large.

(B) Since many parts need to be prepared, that is, set up, for processing the gear, it requires a long time and skill.

(C) The workability is poor because the distance from the operating position to the work attachment / detachment section of the machine is long.

(D) The entire machine is large and requires a large floor area.

(E) Further, JP-A-62-162417 discloses the above-mentioned Japanese Patent Publication No. 30-3900.
Although it compensates for the drawback of No. 3, there is a major drawback that the cutter rotation center axis cannot be arbitrarily tilted with respect to the center axis of the virtual gear.

An object of the present invention is to solve the above problems and to provide a gear cutting machine which can be used as a virtual gear in both crown gears and bevel gears, which can be speeded up and downsized, and which is remarkably simple in setup operation. It was developed.

[Means for solving the problem]

In order to solve the above problems and to achieve the object, the present invention provides a work gear holding unit and a cutter unit on a bed, which is a gear cutting machine, and the cutter unit includes a column and a blade shaft head. Then, the column is arranged so that it can move forward and backward in a transverse direction orthogonal to the direction of movement of the work holding unit, and the tool shaft head is vertically movable in the column, and the tool shaft head is the axial center line of the inner hole. Is arranged so as to be orthogonal to the advancing / retreating direction of the column, and an oscillating body is rotatably fitted in the inner hole. The oscillating body has an inner hole formed at the center of the base end portion and is connected to a motor. The shaft is pierced through the shaft, and the tip surface is notched at an angle of θ with respect to the direction orthogonal to the axis, and a shaft head inner hole is formed inside. The displacement bearing has the blade spindle arranged on the same axis as the blade shaft head. In addition, the displacement shaft is pivotally supported in the shaft inner hole at an angle of θ with respect to the axis of the tool spindle, and the transmission shaft, the displacement shaft, and the tool spindle are configured to co-operate. The tool spindle is configured to be displaceable in the range of 0 to 2θ, and the work holding unit moves the work spindle head through the swivel base on the table that moves back and forth in the cutter unit direction, and the tip of the work spindle moves above the swivel axis. A technical measure was taken: a gear cutting machine arranged so as to be positioned.

[Action]

In the present invention configured as described above, a cutter can be attached to the tip of the blade main spindle to set the blade main spindle at a desired inclination angle, the swing body supporting the blade main spindle can be rotated, and the swing body Since the blade head supporting the blade can make vertical and horizontal sideways motions, it is possible to automatically combine the vertical and horizontal sideways motions to automatically create a virtual gear necessary for the cutter to perform gear cutting. It operates to draw the surface profile of teeth. Further, even if the shape of the gear to be machined is different, the direction of the cutter main shaft can be inclined, so that the cutting edge can be set on the tooth crest surface portion of the virtual gear that matches the shape of the gear.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view, in which the vertical direction is called the Y-axis direction, the left-right direction is called the X-axis direction, and the front-back direction is called the Z-axis direction. 2 is a sectional view taken along the line AA in FIG. 1, in which the inclination angle of the main shaft of the blade is 0.
FIG. 3 shows a state in which the main axis of the blade is tilted at 2θ.

On the bed 2 of the gear cutting machine 1, a pair of parallel sliding guides 3, 3 oriented in the Z-axis direction are arranged on the front side (right side in the figure), and on the back side on the bed 2. Is provided with a pair of parallel sliding guides 4, 4 which are orthogonal to the sliding guides 3, 3 and are oriented in the X-axis direction.

A work holding unit 5 is slidably arranged along the slide guides 3, 3 on the front side slide guides 3, 3.
A cutter unit 6 is slidably arranged along the slide guides 4, 4 on the rear side slide guides 4, 4.

In the work holding unit 5, the table 7 is slidably arranged on the sliding guides 3, 3, and the tip end of the feed screw 8 provided on the table 7 is projected outside the bed 2 and the tip end portion is formed. A servo motor 9 is connected to the table 7, and the table 7 is rotated by the forward / reverse rotation of the servo motor 9 to move the table 7 to the cutter unit 6.
It is configured to move forward and backward.

A notch surface 7A is formed by flatly notching the front right side in the figure on the upper surface of the table 7, and a wall surface 7B of the notch surface 7A is centered on a pivot shaft 10 standing on the upper left rear edge of the table 7. Is formed on the circumferential surface. A swivel base 11 that can swivel and fix around the swivel shaft 10 is mounted on the table 7, and a work spindle head 12 is fixedly disposed on the swivel base 11. Then, the rotary shaft 10 does not coincide with the apex (indicated by P in FIG. 8) of the pitch cone of the work W, so that the work main shaft 13
It is located below the tip.

A work spindle 13 is rotatably supported on the work spindle head 12, and is configured to be driven via a servo motor 14 and a worm gear (not shown). The work W can be attached to and detached from the tip of the work spindle 13. Is configured.

With the above configuration, the work holding unit 5 drives the servo motor 9 to move the table 7 forward and backward with respect to the column 15, and the swivel base 11 is swung to a shape suitable for the work W.
It is possible to rotate and fix the work spindle 13 about the center of the work piece 10, and to rotate the work spindle 13 by driving the servo motor 14.

The cutter unit 6 is mounted on the slide guides 4, 4 on the column 1
5 is slidable along the slide guides 4, 4 in a transverse direction at right angles to the advancing / retreating direction of the table 7, and the tip end of the feed screw 16 provided on the column 15 is fixed to the outer surface of the bed 2. The column 15 is configured to be movable back and forth along the X-axis direction by the forward and reverse rotations of the servo motor 17.

Elevating guides 18, 18 are integrally formed at the front and rear ends of the left end surface of the column 15 in the figure, and a hole 15A is formed in the left end surface of the column 15. A feed screw 19 is vertically arranged in the hole 15A, and an upper end portion of the feed screw 19 is connected to a servo motor 20 arranged above the column 15.

Then, the guide portions 21A of the tool shaft head 21 are slidably fitted to both the elevating guides 18 and 18, and the feed screw 1
The base end of 9 is screwed into the female screw portion 21B (Fig. 2) of the blade shaft head 21, and the forward and reverse rotation of the servomotor 20 rotates the feed screw 19 so that the blade shaft head 21 moves up and down. It is configured.

As shown in FIG. 2, the blade shaft head 21 is formed in a substantially cylindrical shape having an outer rectangular inner hole that is long in the Z-axis direction, and a substantially cylindrical rocking body 22 is provided in a horizontal inner hole 21C. It is loosely fitted to rotate.

A flange 22A is formed at the base end portion of the oscillating body 22, and a large-diameter head portion 22B is formed at the tip end portion. Further, a worm wheel portion 22C corresponding to the worm 23 is engraved along the peripheral surface in the longitudinal middle portion of the outer peripheral surface of the oscillating body 22, and the worm 23 is meshed with the worm wheel portion 22C to form the worm wheel. The tip of 23 is connected to a servo motor 24 (FIG. 1) arranged above the tool shaft head 21. Then, the worm 23 is rotated by driving the servo motor 24, and the oscillating body 22 is rotated.

A transmission shaft 25 is rotatably supported in the inner hole 22D of the oscillating body 22, and a base end portion of the transmission shaft 25 is connected to a motor 26 arranged outside the blade shaft head 21 and the transmission shaft 25 The tip portion projects into the head internal hole 22E of the head portion 22B, and the transmission gear 31 is attached to the tip portion.
Has been fixed.

A circular bearing portion 22F inclined by an angle θ with respect to the axis C ³ of the transmission shaft 25 is formed in the head inner hole 22E of the oscillating body 22, and the displacement bearing 27 is formed in the bearing portion 22F. It is attached so as to be rotatable.

In the displacement bearing 27, a tool spindle 28 is axially supported in an inner hole 27A. The base end portion of the tool spindle 28 projects outside the displacement bearing 27, and the transmission gear 32 is fixed to the projecting portion.
A cutter 29 can be attached to the tip of 28.

As shown in FIG. 2, the base end of the displacement bearing 27 has a desired angle θ (for example, 10 °) with respect to the axis C ¹ of the tool spindle 28.
A displacement shaft 30 in which the position of the axis C ² is changed is rotatably supported. On the displacement shaft 30, two transmission gears 33 and 34 are arranged in parallel, one meshes with the transmission gear 32 of the cutting tool spindle 28, and the other meshes with the transmission gear 31 of the transmission shaft 25. and the positional relationship, the tip end portion of the displacement shaft 30 is fitted to displace the bearing 27 to the bearing portion 22F of the head in the hole 22E, straight to the axial center line C ¹ of the tool spindle 28 and the axial line C ³ of the transmission shaft When set to, it is configured to be fitted into the shaft hole 22G formed at the base end of the head inner hole 22E. Then, when the displacement bearing 27 is rotated along the bearing portion 22F with the displacement shaft 30 as the rotation center, as shown in FIG. 3, the shaft center line C ¹ of the blade main shaft 28 becomes the shaft center line of the transmission shaft 25. The inclination angle is 2θ (for example, 20 °) with respect to C ³ . That is,
The tool spindle 28 can be tilted about the displacement axis 30 with respect to the axis C ³ of the transmission shaft 25 within a range of 0 ° to 2θ, and the tool spindle 28 can be tilted at any tilt angle. 28 is a transmission shaft 25 and a transmission gear driven by the motor 26.
It can be rotated at a constant speed through 31 to 34.

With the above configuration, the turning angle of the swivel base 11 and the inclination angle of the displacement bearing 27 are determined by the gear specifications of the work W and the gear cutting method, and the positions are fixed during cutting.

Further, the servo motors and other driving machines perform desired control by a control mechanism (including NC control) in a general switchboard (not shown), and the cutter 29 rotates (spins) for cutting and the virtual gear. Gear cutting can be performed by rotating (revolving) the circumference of the rotation center axis.

In FIG. 4, the virtual gear shaft 35 is an imaginary point determined by the position of the vertex of the pitch cone of the work W. This point is x
Axis reference position Xo, Y Axis reference position Yo, x, y
It is possible to calculate that the positions are apart from each other. Then, from the center of the virtual gear, the center line C of the oscillator 22 is
R is the distance to ³ (the center line C ² when the inclination angle of the displacement bearing 27 is 0 °), and the angle θ ₁ from the vertical plane passing through the virtual gear center.
The distant position is the cutting start point P ₁ , from which the angle θ ₂
The rotated position is the cutting end point P ₂ . These R, θ ₁ and θ ₂ are also calculated.

Here, the point on the way between P _{1 and} P ₂ is θ, which is the angle from the vertical plane passing through the center of the virtual gear, and the distance from the reference position on the X axis and Y axis in X and Y coordinates is X axis X = R -SIN? -X Y-axis Y = y-R-COS?

At this time, the axis C ³ of the tool shaft head 21 also rotates from the reference position by θ ₂ . When the number of teeth of the work W is Zw and the number of teeth of the virtual gear is Zc, the axis line C ³ of the oscillator 22 (when the inclination angle of the displacement bearing 27 is θ °, the axis line C ^{1 of the} tool spindle 28) ) Is rotated by θ ₂ , the work spindle 13 rotates around its axis C ¹ . A predetermined cutting process is performed by rotating only.

When the cutting process for one tooth is completed, the table 7 retracts in the Z-axis direction to a position where the work W and the cutter 29 do not interfere with each other. Then, it returns from the center point P ₂ of the oscillating body 22 to the point P ₁ , and during this time, the work spindle 13 subtracts or increases the angle of one tooth of the work W from the rotation angle required for cutting, that is, Only rotate in the opposite direction to cutting. Next, the table advances in the cutter direction along the Z axis to process the next tooth. By repeating this, all teeth can be processed.

These required series of operations are performed by controlling the NC of each servo motor. That is, with reference to the pulse signal of the servo motor 14 for driving the work spindle 13, the X-axis servo motors 17, Y in the cutter unit 6 are used.
The axial servomotor 20 changes the position and speed as the machining progresses, and at the same time, the servomotor for driving the oscillator 22.
24 is a control with a certain synchronism. The above description has been given by using the annular milling cutter as an example. However, even if a CBN tool or a cup grindstone is used in place of the cutter, it is possible to fabricate a magnifying bevel gear by a completely swinging motion. Another method of gear cutting is to change the depth of cutting as the virtual gear and the work make a creative motion. At this time, if the series of operations described above is further synchronized with the movement of the table 7 in the Z-axis direction by the servo motor 9, it can be easily performed. The machine according to the present invention is
Even when using a disk-shaped front hob for the cutter, the blade spindle 28
This can be easily realized by using the driving motor 26 as a servo motor and simultaneously controlling a series of operations with other servo motors 14. Further, in the case of hypoidia, it can be easily processed by changing the Y-axis reference position by the offset amount.

[Advantages of the Invention] The present invention configured as described above has the following advantages.

(A) Since the cutter main shaft can be supported in an inclined shape without using the conventional large revolving body that holds the cutter and expresses the virtual gear, there is an effect that the speed can be increased.

(B) Since skill and time are not required for the setup for machining the gear, there is an effect that workability is superior and productivity can be improved.

(C) Since the entire machine can be made compact, there is an effect that the required floor area can be reduced and the factory space can be utilized.

(D) When machining a hypoid gear, by offsetting the small gear and the large gear by changing the ascending / descending reference position of the tool shaft head, there is an effect that the offset mechanism of the work spindle can be dispensed with.

(E) By making the distance from the reference plane for machining or assembling the work to the cone apex by changing the reference position of the horizontal feed and the reference position of the table, the adjustment mechanism in the work spindle direction becomes unnecessary. There is an effect that can be.

[Brief description of drawings]

The drawings relate to an embodiment of the present invention, in which FIG. 1 is a perspective view and FIG.
The figure is a cross-sectional view taken along the line A-A in FIG.
3), and FIG. 3 shows the first when the angle of inclination of the blade axis is 2θ.
Fig. 4 is a cross-sectional view taken along the line AA in the drawing, Fig. 4 is a conceptual diagram showing the movement of the blade main shaft, and Figs. 5 to 9 are perspective views showing the relationship between the cutter, the work, and the virtual gear 0 in the conventional example. 1 ... Tooth cutter, 2 ... Bed 3, 4 ... Sliding guide, 5 ... Work holding unit, 6 ... Cutter unit, 7 ... Table, 7A ... Notch surface, 7B ... Wall surface, 8 …… Feed screw, 9 …… Servo motor, 10 …… Swivel axis, 11 …… Swivel base, 12 …… Work spindle head, 13 …… Work spindle, 14 …… Servo motor, W …… Work, 15 …… Column, 16 …… Feed screw, 17 …… Servo motor, 18 …… Lift guide, 19 …… Feed screw, 20 …… Servo motor, 21 …… Cut shaft head, 21A …… Guide section, 21B …… Female thread section , 21C …… Inner hole, 22 …… Oscillator, 22A …… Flange, 22B …… Head, 22C …… Warm wheel part, 22D …… Inner hole, 22E …… Head inner hole, 22F …… Bearing part , 22G …… Shaft hole, 23 …… worm, 24 …… Servo motor, 25 …… Transmission shaft, 26 …… Motor, 27 …… Displacement bearing, 27 A …… Inner hole, 28 …… Tool spindle, 29 …… Cutter, 30 …… Displacement axis, 31,32,33,34 …… Transmission gear, 35 …… Virtual gear central axis.

Claims (1)

(57) [Claims] 1. A spiral tooth gear cutting machine having a work holding unit and a cutter unit on a bed, wherein the cutter unit is composed of a column and a blade shaft head.
A column is arranged so as to be able to move forward and backward in a direction orthogonal to the forward and backward direction of the work holding unit, and a blade shaft head is vertically movable in the column. The blade shaft head has an axial center line of the inner hole of the column. The oscillating body is horizontally arranged so as to be orthogonal to the advancing / retreating direction, the oscillating body is fitted in the inner hole, and the oscillating body is freely rotatable along the inner hole peripheral surface by the worm arranged between the oscillating body and the column. The oscillating body is formed such that a conduction shaft connected to an external motor penetrates through an inner hole at the center of the base, and the front end surface of the shaft head inner hole is formed at an angle θ with respect to the direction orthogonal to the axis. The displacement bearing in the shaft head inner hole is loosely fitted to the base of the shaft head inner hole with the displacement shaft of the base end portion thereof rotated so that the tip of the shaft center line contacts the extension of the shaft center line of the conduction shaft at a θ angle. The main shaft of the tool is fitted in the inner hole of the displacement bearing so as to incline at an angle of θ with respect to the axis of the displacement shaft. The main shaft, the displacement shaft, and the transmission shaft are configured to move together, and the shaft center line of the blade main shaft on the same axis as the transmission shaft is displaceable within a range of 0θ to 2θ about the displacement shaft. The holding unit is provided with a work spindle head on a table that moves back and forth in the direction of the cutter unit via a swivel base, and the tip of the work spindle is located above the swivel axis, and each drive unit is an NC-controlled servo. A gear cutting machine characterized by being driven and controlled by a motor.