JP5418270B2 - Feed rate control method and feed rate control device - Google Patents

Description

  The present invention relates to a feed rate control method and apparatus for controlling the relative feed rate of a tool with respect to the workpiece when machining the workpiece with a tool.

  Conventionally, in order to perform high-precision processing, Patent Document 1 describes that the feed speed of a grindstone is controlled so that the rotational driving power of the grindstone is maintained at a target power. That is, the feed rate of the grindstone is controlled so that the machining efficiency of the entire grindstone at a certain moment during machining does not exceed the set upper limit value. Here, the “machining efficiency” corresponds to the machining volume per unit time. For example, when grinding the outer peripheral surface of a cylindrical workpiece with a cylindrical grindstone, the processing efficiency of the entire grindstone can be obtained by multiplying the feed rate of the grindstone by the cutting depth and the grinding width. it can.

Japanese Patent Laid-Open No. 2003-291064

  However, even if the processing efficiency of the entire grindstone at a certain moment is below the set upper limit value, depending on the shape of the grindstone and the work piece, if the processing area by the grindstone at a certain moment is viewed locally, machining in a small area The efficiency is relatively low, and there may be a case where the processing efficiency in other micro regions is relatively high. In such a case, there is a possibility that processing burn may occur in a region where the processing efficiency in the minute region is high. As described above, even if only the processing efficiency of the entire grindstone at a certain moment is monitored, there is a risk that processing burn may occur when viewed locally.

  This invention is made | formed in view of such a situation, and it aims at providing the feed rate control method and feed rate control apparatus which can prevent generation | occurrence | production of local work burn.

In order to solve the above-described problems, the present invention controls the feed rate so that the machining efficiency in the minute region is equal to or less than the set upper limit value.
That is, the feed speed control method according to claim 1 is characterized in that in processing a workpiece with a tool, the feed rate control method controls a relative feed rate of the tool with respect to the workpiece. When the machining area by the tool at each moment during machining is divided into a plurality of minute areas, the feed rate is controlled so that the machining efficiency in each minute area is equal to or less than a set upper limit value.

A feature of the invention according to claim 2 is that the feed speed is controlled so that the maximum value of the machining efficiency of the microscopic area at each moment during machining is equal to or greater than a set lower limit value.
A feature of the invention according to claim 3 is that the workpiece is formed such that concave teeth and convex teeth are continuously formed in the circumferential direction, and the concave teeth mesh with the convex teeth of the counter gear. It is a concavo-convex gear that can transmit power between the two, and is a gear that rotates around a crossing axis that intersects the rotation center axis of the counter gear.
A feature of the invention according to claim 4 is that the tool is a disk-shaped grindstone that grinds the workpiece while rotating around a central axis, and the minute region is a disk-shaped grinding region defined by the disk-shaped grindstone. It is an area divided along the surface of the cross section in the axial direction of the grindstone.

  The feature of the invention according to claim 5 is that the minute region formed by the disc-shaped grindstone at each moment during machining is regarded as a plane, and the disc-shaped grindstone at each moment during machining is relative to the workpiece. When the moving direction is regarded as the straight direction, the machining efficiency in the minute region is the contact arc length with the workpiece at each position on the grindstone surface in the axial section of the disc-shaped grindstone, and the disc-like shape. The calculation is performed by multiplying the normal direction component of the minute area regarded as the planar shape at the relative feed speed of the grindstone with respect to the workpiece.

  The feature of the invention according to claim 6 is that a coefficient representing the difficulty of reaching the coolant is set in accordance with the surface position of the tool, and the machining efficiency in the minute region is the area of the minute region and the minute region. The basic machining efficiency calculated based on the feed speed of the tool to the workpiece is a value corrected by multiplying the coefficient.

In the above, the case where this invention was grasped | ascertained as a feed rate control method was demonstrated. In addition, the present invention can be grasped as a feed speed control device.
That is, the feature of the invention of the feed rate control device according to claim 7 is a feed rate control device for controlling a relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool. When the machining area by the tool at each moment during machining is divided into a plurality of minute areas, the feed rate is controlled so that the machining efficiency in each minute area is equal to or less than a set upper limit value.

  The invention according to claim 8 is characterized in that the feed speed control device controls the NC machine tool based on the NC program, and each of the minute speeds with respect to the feed speed of the tool to the workpiece in the NC program. This is an NC device that is controlled by a feed speed that is corrected so that the machining efficiency in the region is equal to or less than the set upper limit value.

  The feature of the invention according to claim 9 is calculated so that the machining efficiency in each of the micro areas is equal to or less than a set upper limit value when the machining area by the tool at each moment during machining is divided into a plurality of micro areas. An NC program generating device for generating an NC program based on the feed speed, and a relative feed speed of the workpiece of the tool based on the feed speed of the NC program, And an NC device for processing the workpiece.

A feature of the invention of the feed rate control method according to claim 10 is as follows:
In a feed rate control method for controlling a relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool,
When the machining area by the tool at each moment during machining is divided into a plurality of minute areas, the machining efficiency in each minute area is calculated,
Multiplying the calculated machining efficiency in the micro area by a predetermined direction component in the normal direction unit vector of the micro area,
For the multiplication value, integration over the machining area by the tool,
The feed speed is controlled so that the integral value is equal to or less than the set upper limit value.

  A feature of the invention according to claim 11 is that the tool is a disc-shaped grindstone that grinds the workpiece while rotating around a central axis, and the predetermined direction is a rotation axis direction of the disc-shaped grindstone and the disc. It is that it is at least any one of the directions orthogonal to the rotating shaft of a grindstone.

A feature of the invention of the feed rate control device according to claim 12 is that:
In a feed rate control device that controls the relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool,
When the machining area by the tool at each moment during machining is divided into a plurality of minute areas, the machining efficiency in each minute area is calculated,
Multiplying the calculated machining efficiency in the micro area by a predetermined direction component in the normal direction unit vector of the micro area,
For the multiplication value, integration over the machining area by the tool,
The feed speed is controlled so that the integral value is equal to or less than the set upper limit value.

  According to the invention according to claim 1 configured as described above, the relative feed speed of the tool is controlled so that the machining efficiency in the minute region is equal to or less than the set upper limit value. Therefore, even if the processing region by the tool at a certain moment during processing is viewed locally, it is possible to prevent processing burn from occurring in each part.

The lower the relative feed rate of the tool, the more the work burn can be prevented. On the other hand, if the relative feed speed of the tool is lowered, the machining time is prolonged. Therefore, according to the second aspect of the present invention, since the relative feed speed of the tool is controlled so that the maximum value of the machining efficiency in the minute amount region is equal to or larger than the set lower limit value, local machining burn is caused. The processing time can be shortened while preventing the above.
When the workpiece is made as in the invention according to claim 3, the machining efficiency of the respective micro regions at a certain moment is different. Therefore, by applying the present invention to the workpiece, it is possible to prevent the workpiece from being burnt.

According to the invention which concerns on Claim 4, the grinding process by a disk shaped grindstone is made into object. In processing using a disc-shaped grindstone, the contact between the disc-shaped grindstone and the workpiece is continuous, so that it is easy to calculate the processing efficiency in a minute region. Therefore, the desired feed rate control can be reliably performed.
According to the invention which concerns on Claim 5, in the grinding process using a disk shaped grindstone, the processing efficiency of a micro area | region can be calculated without considering the rotation phase (theta) of a disk shaped grindstone. Therefore, the processing efficiency of a minute region can be calculated very easily.

  According to the sixth aspect of the invention, the machining efficiency is determined in consideration of the influence of the coolant during machining. For example, the maximum value of the processing efficiency of the minute region for preventing the processing burn from occurring is lower in the portion where the coolant is difficult to reach than in the portion where the coolant is easily reached. By calculating the machining efficiency of the minute region using the coefficient representing the difficulty of reaching the coolant in this way, it is possible to reliably prevent the occurrence of work burn.

  According to the invention concerning Claim 7, there exists the same effect as the effect in the feed speed control method concerning Claim 1. According to the eighth aspect of the present invention, the feed rate control device is an NC device, and the NC device controls the feed rate that has been input to a desired feed rate. Here, in general, the NC apparatus analyzes an input NC program and interpolates a feed speed for controlling an actual machine tool. For example, at the moment when the feed speed in the NC program is changed, interpolation is performed so that the actual feed speed changes smoothly. Therefore, the NC device may correct the feed speed of the NC program before interpolation to the desired feed speed of the present invention, or the desired feed speed of the present invention relative to the feed speed after interpolation. You may make it correct | amend.

According to the ninth aspect of the present invention, the NC program generation device corrects the desired feed speed of the present invention. That is, the NC device controls the machine tool based on the desired feed rate information of the present invention. In any of these cases, the relative feed rate of the tool can be set to a desired feed rate.
The other features of the above-described feed speed control method of the present invention can be similarly applied to the feed speed control apparatus of the present invention. In this case, the same effect is obtained.

  Moreover, according to the invention which concerns on Claim 10, the total value of the force of the predetermined direction component concerning a tool is computable by using the machining efficiency of each micro area | region. By controlling the feed rate so that the total value of the forces in the predetermined direction component is not more than the set upper limit value, it is possible to obtain an appropriate feed rate according to the support rigidity of the tool with respect to the force in the predetermined direction component. it can.

According to the invention which concerns on Claim 11, it can grasp | ascertain with respect to the force of the component of a rotating shaft direction (axial direction), or the component of a direction (radial direction) orthogonal to a rotating shaft. That is, it is possible to control the feed rate after appropriately considering the support rigidity in the axial direction and radial direction of the tool.
The feature of the invention of the feed rate control device according to claim 12 is the same as the effect of the feed rate control method according to claim 10.

It is an axial sectional view of an oscillating gear device. (A) shows the case where the convex tooth pin is formed separately from the fixed shaft main body and the output shaft main body, and (b) shows the convex tooth pin formed integrally with the fixed shaft main body and the output shaft main body. The case where it is done is shown. It is the enlarged view of the meshing part of a convex-tooth pin (convex tooth) and a rocking gear, Comprising: It is the figure seen from the axial direction of the convex-tooth pin. (A) shows the case where the convex tooth pin is formed separately from the fixed shaft, and (b) shows the case where the convex pin is formed integrally with the fixed shaft. It is a perspective view of a rocking concave tooth. (A) is the figure which looked at the rocking | fluctuation concave tooth from the radial direction outer side of the rocking gear. (B) is the figure which looked at the rocking concave tooth from the rotation center axis direction of the rocking gear. It is a figure which shows the relative operation | movement of the rocking | fluctuation concave tooth of a rocking gear, and a convex-tooth pin (convex tooth). (A1) is the figure seen from the rotation center axis direction of the rocking | fluctuation gear in the relative position of both before a convex-tooth pin meshes with a rocking | fluctuation concave tooth. (A2) is the figure seen from the right side of (a1). (B1) is the figure seen from the rotation center axis direction of the rocking | fluctuation gear in the relative position of both in the state which the convex-tooth pin has meshed | engaged with the rocking | fluctuation concave tooth. (B2) is the figure seen from the right side of (b1). (C1) is the figure seen from the rotation center axis direction of the rocking | fluctuation gear in the state of both when a convex-tooth pin leaves | separates from a meshing state with respect to a rocking | fluctuation concave tooth. (C2) is a view from the right side of (c1). In FIG. 5, the reference axis of the convex tooth pin (the one-dot chain line in the longitudinal direction of the convex tooth pin) and the center position (black circle) of the convex tooth pin are shown. (A) is a figure which shows the movement locus | trajectory of the reference | standard axis | shaft of a convex-tooth pin with respect to a rocking | fluctuation gear, and the center position of a convex-tooth pin when it sees from the rotation center axis direction of a rocking | fluctuation gear. (B) It is a figure which shows the operation | movement locus | trajectory of the reference shaft of the convex-tooth pin with respect to an oscillation gear, and the center position of a convex-tooth pin when it sees from the radial direction of an oscillation gear. The number in the circle matches the axis number. In 1st embodiment, it is a figure explaining the axis | shaft structure of the machine tool required. (A) shows the axis configuration of the machine tool in a plane parallel to the second linear motion axis and the third linear motion axis, and (b) shows the work in a plane parallel to the first linear motion axis and the second linear motion axis. The axis configuration of the machine is shown. The number in the circle matches the axis number. It is a figure which shows a toroidal grindstone (disk-shaped grindstone). (A) is the figure which looked at the toroidal grindstone from the said rotating shaft direction, (b) is the figure seen from radial direction. (A) is a perspective view of a toroidal grindstone, (b) is a figure which shows the micro area | region dA. FIG. 6 is a distribution diagram of machining efficiency Q ″ (w, θ, t) at times t1, t2, and t3. It is a figure which shows setting upper limit Q "set1 and setting lower limit Q" set2. 2nd embodiment: It is a figure which shows the relationship between a toroidal grindstone and a workpiece, and shows feed speed vector F, normal vector N, and contact arc length L. Second embodiment: (a) shows a two-dimensional coordinate of a position w on the surface of the grindstone in the axial section and a contact arc length L with the workpiece 15 at the surface position w of the axial section. It is a figure which shows the contact range with a workpiece. (B) is a figure which shows processing efficiency Q '(w) with respect to the position w on the grindstone surface in an axial cross section. Second Embodiment: Distribution diagram of machining efficiency Q ′ (w, t) at each of times t1, t2, and t3. FIG. 6 is a diagram showing a case where the maximum value of machining efficiency Q ′ (w, t) at each of times t1, t2, and t3 is made to coincide with a set value Q′set. Third embodiment: Distribution diagram of machining efficiency Q ′ (w, t) in consideration of coefficient C at each of times t1, t2, and t3. 4th embodiment: It is a block diagram which shows an apparatus structure. 5th embodiment: It is a block diagram which shows an apparatus structure. 6th embodiment: It is a block diagram which shows an apparatus structure. In 7th embodiment, it is sectional drawing of the power transmission device comprised by the uneven | corrugated gear which has an intersection axis. (A) shows the case where the convex tooth pin is formed separately from the input shaft main body, and (b) shows the case where the convex tooth pin is formed integrally with the input shaft main body. FIG. 20 is a diagram illustrating an axial direction component and a radial direction component in a normal direction unit vector N (w, θ) of a minute region in the eighth embodiment.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying a feed rate control method and apparatus according to the present invention will be described below with reference to the drawings. Here, a case will be described in which the workpiece is an oscillating gear that constitutes an oscillating gear device, and the machining part is a concave tooth of the oscillating gear. This oscillating gear device corresponds to one having two sets of the relationship between the concave and convex gears and the counter gear when the rotational center axis of the concave and convex gear and the rotational center axis of the counter gear intersect. In the following description, the oscillating gear corresponds to the “concave gear” of the present invention, and the fixed shaft 12 and the output shaft 13 correspond to the “counter gear” of the present invention.

<First embodiment>
(1) Axis Configuration of Machine Tool A machine tool as a control target by the feed speed control method and the feed speed control device of the first embodiment has a six-axis configuration having three orthogonal linear motion axes and three rotation axes. This will be described as a case. As will be described later, one rotation axis is an axis that rotates around an axis parallel to a predetermined linear movement axis among the three linear movement axes, and the remaining two rotation axes are parallel to the other one linear movement axis. An axis that rotates around an axis. That is, the remaining two rotation axes are axes that rotate about axes parallel to each other.

(2) Configuration of Oscillating Gear Device A configuration of an oscillating gear device in which the oscillating gear that is the object of processing of the present invention is used will be described with reference to FIGS. Here, FIG. 1A shows a case where the convex tooth pins 12b and 13b are formed separately from the fixed shaft main body 12a and the output shaft main body 13a, and FIG. 1B shows a convex tooth pin. The case where 12b and 13b are integrally formed with respect to the fixed shaft main body 12a and the output shaft main body 13a is shown. In the following, description will be made mainly with reference to FIG. 1 (a), and only differences from FIG. 1 (a) will be described with reference to FIG. 1 (b).

  The oscillating gear device is used as a speed reducer and has attracted attention as a speed reducer capable of obtaining a very large reduction ratio. As shown in FIG. 1 (a), the oscillating gear device mainly includes an input shaft 11, a fixed shaft 12 (corresponding to the “mating gear” of the present invention), and an output shaft 13 (the “mating member of the present invention”. The outer ring 14, the inner ring 15 (corresponding to the “concave gear” of the present invention), and the rolling elements 16.

  The input shaft 11 constitutes a rotor of a motor (not shown) and is a shaft that rotates when the motor is driven. The input shaft has a cylindrical shape and rotates around a rotation center axis A (shown in FIG. 1A). An inclined surface 11 a is formed on the inner peripheral surface of the input shaft 11. The inclined surface 11a is a cylindrical inner peripheral surface having an axis B inclined at a slight angle with respect to the rotation center axis A as a central axis.

  The fixed shaft 12 (corresponding to the “mating gear” of the present invention) is fixed to a housing (not shown). The fixed shaft 12 includes a fixed shaft main body 12a and a plurality of convex tooth pins 12b. The fixed shaft main body 12a is a cylindrical member having the axis A as the rotation center axis. A plurality of (G1) convex pins 12b (corresponding to the “convex teeth of the counter gear” of the present invention) are supported at equal intervals in the circumferential direction of the rotation center axis A on the axial end surface of the fixed shaft main body 12a. Yes. Each convex tooth pin 12b is formed in a columnar shape or a cylindrical shape, and both ends thereof are supported by the fixed shaft main body 12a so that the convex tooth pins 12b are arranged radially. Further, each convex tooth pin 12b is fixed to the fixed shaft main body 12a so as to be rotatable about the axial direction of the convex pin 12b (reference axial direction) and the radial axis of the fixed shaft main body 12a. It is supported. Furthermore, a part of the convex pin 12b protrudes from the axial end surface of the fixed shaft main body 12a. That is, the fixed shaft 12 functions as a gear having convex teeth with the number of teeth Z1.

  In the above description, as shown in FIGS. 1A and 2A, the convex pin 12b of the fixed shaft 12 is formed separately from the fixed shaft main body 12a, and the fixed shaft main body 12a I was supported. In addition, as shown in FIGS. 1B and 2B, the convex pin 12b can be formed integrally with the fixed shaft body 12a. In this case, the integrally formed convex tooth pin 12b is a portion corresponding to the fixed shaft main body 12a, similar to the portion protruding from the axial end surface of the fixed shaft main body 12a of the convex tooth pin 12b when formed separately. Projects from the axial end face.

  The output shaft 13 (corresponding to the “counter gear” of the present invention) is supported so as to be rotatable around the rotation center axis A with respect to a housing (not shown), and is connected to an output member (not shown). The output shaft 13 includes an output shaft main body 13a and a plurality of convex tooth pins 13b. The output shaft main body 13a is a cylindrical member having the axis A as the rotation center axis. That is, the output shaft main body 13a is provided coaxially with the input shaft 11 and the fixed shaft main body 12a.

  A plurality of (G4) convex pins 13b (corresponding to “the convex teeth of the mating gear” of the present invention) are supported at equal intervals in the circumferential direction of the rotation center axis A on the axial end surface of the output shaft main body 13a. Yes. And each convex-tooth pin 13b is formed in the column shape or cylindrical shape, and the both ends are supported by the output-shaft main body 13a so that the said convex-tooth pin 13b may be arrange | positioned radially. Further, each convex tooth pin 13b is attached to the output shaft main body 13a so as to be rotatable about the axial direction (reference axial direction) of the convex tooth pin 13b and the radial axis of the output shaft main body 13a. It is supported. Further, the axial end surface that supports the convex pin 13b in the output shaft main body 13a is opposed to the axial end surface that supports the convex pin 12b in the fixed shaft main body 12a with a predetermined distance in the axial direction. It is provided as follows. Furthermore, a part of the convex pin 13b protrudes from the axial end surface of the output shaft main body 13a. That is, the output shaft 13 functions as a gear having convex teeth with the number of teeth Z4.

  In the above description, the convex pin 13b of the output shaft 13 is formed separately from the output shaft main body 13a and supported by the output shaft main body 13a. In addition, as shown in FIG. 1B and FIG. 2B, the convex pin 13b can be integrally formed with the output shaft main body 13a. In this case, the integrally formed convex tooth pin 13b has a portion corresponding to the output shaft main body 13a in the same manner as the portion protruding from the axial end surface of the output shaft main body 13a of the convex tooth pin 13b when formed separately. Projects from the axial end face.

  The outer ring 14 is formed in a cylindrical shape having a raceway surface on the inner peripheral surface. The outer ring 14 is press-fitted to the inclined surface 11 a of the input shaft 11. That is, the outer ring 14 is integrated with the input shaft 11 and can rotate about the rotation center axis B.

  The inner ring 15 (corresponding to the “concave gear” of the present invention) is formed in a substantially cylindrical shape. A rolling surface 15 a is formed on the outer peripheral surface of the inner ring 15. Furthermore, a plurality (G2) of swinging concave teeth 15b are formed at equal intervals in the circumferential direction on the end surface of one of the inner rings 15 in the axial direction (the right side in FIG. 1A). Further, a plurality (G3) of swinging concave teeth 15c are formed at equal intervals in the circumferential direction on the end surface of the inner ring 15 on the other side in the axial direction (left side in FIG. 1A).

  The inner ring 15 is spaced apart inward in the radial direction of the outer ring 14 and sandwiches a plurality of rolling elements (spheres) 16. That is, the inner ring 15 has a rotation center axis B inclined with respect to the rotation center axis A. Therefore, the inner ring 15 can rotate around the rotation center axis B with respect to the input shaft 11. Furthermore, the inner ring 15 can rotate around the rotation center axis A as the input shaft 11 rotates around the rotation center axis A by driving the motor.

  Furthermore, the inner ring 15 is disposed between the axial direction of the fixed shaft 12 and the output shaft 13. Specifically, the inner ring 15 is disposed between an axial end surface that supports the convex pin 12b of the fixed shaft main body 12a and an axial end surface that supports the convex pin 13b of the output shaft main body 13a. Yes. Then, one swinging concave tooth 15 b of the inner ring 15 meshes with the convex tooth pin 12 b of the fixed shaft 12. The other swinging concave tooth 15 c of the inner ring 15 meshes with the convex tooth pin 13 b of the output shaft 13.

  Since the inner ring 15 swings around the rotation center axis A with respect to the fixed shaft 12, a part of one swinging concave tooth 15b of the inner ring 15 (upper part in FIG. 1A) is Although meshing with the convex pin 12b of the fixed shaft 12, the other part of the one swinging concave tooth 15b (the lower portion in FIG. 1A) is the convex pin 12b of the fixed shaft 12. It is away from. Further, since the inner ring 15 swings around the rotation center axis A with respect to the output shaft 13, a part of the other swinging concave tooth 15c of the inner ring 15 (the lower part in FIG. 1A) is The other oscillating concave tooth 15c (the upper part of FIG. 1A) is engaged with the convex tooth pin 13b of the output shaft 13. It is away from.

  For example, the number of teeth Z1 of the convex tooth pin 12b of the fixed shaft 12 is set to be smaller than the number of teeth Z2 of one swinging concave tooth 15b of the inner ring 15, and the number of teeth of the convex pin 13b of the output shaft 13 is set. Z4 and the number of teeth Z3 of the other swinging concave tooth 15c of the inner ring 15 are set to be the same. Thereby, the output shaft 13 decelerates (differential rotation) with respect to the rotation of the input shaft 11. That is, in this example, differential rotation is performed between the inner ring 15 and the fixed shaft 12, but differential rotation is not performed between the inner ring 15 and the output shaft 13. However, by setting the number of teeth Z4 of the convex pin 13b of the output shaft 13 and the number of teeth Z3 of the other swinging concave tooth 15c of the inner ring 15 to be different from each other, differential rotation occurs between them. You can also These can be appropriately set according to the reduction ratio.

  In the oscillating gear device shown in FIG. 1 (a), the meshing portion of the convex tooth pin 12b of the fixed shaft 12 that generates differential rotation and one oscillating concave tooth 15b of the inner ring 15 is shown in FIG. 2 (a). As shown. Further, in the oscillating gear device shown in FIG. 1 (b), the meshing portion between the convex tooth pin 12b of the fixed shaft 12 that generates differential rotation and one oscillating concave tooth 15b of the inner ring 15 is shown in FIG. ) As shown. Here, Fig.2 (a) shows the case where the convex-tooth pin 12b in the fixed axis | shaft 12 is formed separately with respect to the fixed axis | shaft main body 12a. FIG. 2B shows the case where the convex pin 12b on the fixed shaft 12 is integrally formed with the fixed shaft main body 12a. The present embodiment can be applied to both cases of FIGS. When differential rotation occurs between the output shaft 13 and the inner ring 15, the meshing portion between the convex pin 13b of the output shaft 13 and the other swinging concave tooth 15c of the inner ring 15 is also shown in FIG. a) Same as (b). In the following description, only the meshing portion between the fixed shaft 12 and the swing gear 15 will be described.

  Here, the swinging concave tooth 15b has a shape as shown in FIGS. That is, the cross-sectional shape of the swinging concave tooth 15b in the direction orthogonal to the tooth gap direction is generally a semicircular arc concave as shown in FIGS. 2 and 4A. Specifically, the cross-sectional shape has a shape in which an opening edge portion having an arcuate concave shape hangs down. Furthermore, as shown in FIG. 3 and FIG. 4B, the swinging concave teeth 15b are shaped so that the groove width widens toward both ends in the tooth groove direction. This is because the number of teeth Z1 of the convex pin 12b is different from the number of teeth Z2 of the swinging concave tooth 15b.

(2) Generation method of NC program for processing concave teeth of swing gear (2.1) Basic concept Next, the swing of the inner ring 15 (hereinafter referred to as “oscillation gear”) in the swing gear device described above will be described. A method for generating an NC program for machining the moving concave teeth 15b will be described. The same applies to the generation method of the NC program for machining the rocking concave teeth 15c of the rocking gear 15. First, a three-dimensional CAD model or mathematical model of the oscillating gear 15 and the convex tooth pin 12b is generated. This model is an operation model in which the swing gear 15 and the fixed shaft 12 rotate differentially.

  Subsequently, a relative movement locus of the convex pin 12b with respect to the swinging concave tooth 15b when the two are differentially rotated is extracted (trajectory extraction step). When extracting the relative movement locus, the movement locus of the convex pin 12b is extracted assuming that the swinging concave tooth 15b is fixed and the convex pin 12b moves relative to the swinging concave tooth 15b. The movement locus of this convex tooth pin 12b includes a central axis 12X (hereinafter referred to as “reference axis”) of the convex tooth pin 12b and a center point 12C (hereinafter referred to as “the central axis”) of the convex tooth pin 12b. (Referred to as “pin center point”). The reference axis 12X of the convex pin 12b corresponds to an axis parallel to the intersection line between the tooth thickness center plane of the convex pin 12b and the reference conical surface.

  Subsequently, an NC program which is an operation locus of the machining tool is generated by performing coordinate conversion of the relative operation locus of the convex tooth pin 12b with respect to the extracted swing gear 15 (coordinate conversion process). This NC program corresponds to an operation locus of a processing tool for processing the swinging concave tooth 15b in the workpiece coordinate system. Details of this will be described later.

  In addition, based on the produced | generated NC program, NC apparatus processes the rocking | fluctuation concave tooth 15b of the rocking | fluctuation gear 15 by moving a processing tool relatively with respect to a disk shaped workpiece | work. Here, the machining tool is moved relative to the disc-shaped workpiece so that the relative motion trajectory of the machining tool with respect to the disc-shaped workpiece matches the motion trajectory of the convex tooth pin 12b extracted above. Here, the disk-shaped workpiece is a material that forms the shape of the swing gear 15 before the processing of the swing concave teeth 15b.

Hereinafter, the locus extraction process and the coordinate conversion process will be described in detail.
(2.2) Trajectory Extraction Step The trajectory extraction step will be described with reference to FIGS. 5 (a1) (a2) (b1) (b2) (c1) (c2). In each figure of FIG. 5, the shape of the convex-tooth pin 12b shows only the part of the convex-tooth pin 12b which protrudes with respect to the fixed shaft main body 12a of the fixed shaft 12 shown to Fig.2 (a) (b). That is, in each figure of FIG. 5, the convex-tooth pin 12b has shown the common part of the convex-tooth pin 12b shown to Fig.2 (a) (b).

  In a state before the convex tooth pin 12b meshes with the swinging concave tooth 15b, as shown in FIG. 5 (a1), the rotational center axis direction of the swinging gear 15 (“B” in FIGS. 1 (a) and 1 (b)). When viewed from the above, the reference shaft 12X of the convex pin 12b is inclined to the right in FIG. 5 (a1) with respect to the tooth gap direction 15X of the swinging concave tooth 15b. Furthermore, as shown in FIG. 5 (a2), when viewed from the direction perpendicular to the tooth gap direction 15X of the contact surface of the reference conical surface of the swinging concave tooth 15b, the reference axis 12X of the convex tooth pin 12b is Further, the swinging concave tooth 15b is inclined to the left side in FIG. 5 (a2) with respect to the tooth gap direction 15X. In both figures, the pin center point 12C of the convex tooth pin 12b is located at a position shifted from the tooth gap direction 15X of the swinging concave tooth 15b.

  Next, in a state where the convex pin 12b is engaged with the swinging concave tooth 15b, as shown in FIGS. 5 (b1) and (b2), the tooth groove direction 15X of the swinging concave tooth 15b and the reference of the convex pin 12b. The axis 12X coincides. Naturally, the pin center point 12C of the convex tooth pin 12b also coincides with the tooth gap direction 15X of the swinging concave tooth 15b.

  Next, in a state where the convex pin 12b is disengaged from the meshing state with respect to the swinging concave tooth 15b, as shown in FIG. 5 (c1), the rotational center axis direction of the swinging gear 15 (FIG. 1 (a)). ) When viewed from (B) “B”), the reference shaft 12X of the convex pin 12b is inclined to the left in FIG. 5 (c1) with respect to the tooth gap direction 15X of the swinging concave tooth 15b. Yes. Furthermore, as shown in FIG. 5 (c2), when viewed from the direction orthogonal to the tooth gap direction 15X of the contact surface of the reference conical surface of the swinging concave tooth 15b, the reference axis 12X of the convex tooth pin 12b is Further, the swinging concave tooth 15b is inclined to the left side of FIG. 5 (c2) with respect to the tooth gap direction 15X. In both figures, the pin center point 12C of the convex tooth pin 12b is located at a position shifted from the tooth gap direction 15X of the swinging concave tooth 15b.

  That is, the operation locus of the reference shaft 12X of the convex pin 12b and the operation locus of the pin center point 12C are as shown in FIG. The motion trajectory of the reference shaft 12X can be expressed by being decomposed into a first linear motion shaft, a second linear motion shaft, a third linear motion shaft, a fourth rotational shaft, a fifth rotational shaft, and a sixth indexing shaft. . Here, in FIG. 6 and the following figures, the numbers in the circles correspond to the numbers of the respective axes. For example, the axis indicated by the numeral “1” in ○ is the first linear movement axis.

  That is, the first linear movement shaft is a reference position (predetermined position) of the convex tooth pin 12b, which is a concave tooth formation surface (in the present embodiment, “axial end surface”) of the disk-shaped workpiece (swing gear 15). ) To move in a direction perpendicular to the surface in contact with. The second linear movement shaft moves the reference position of the convex tooth pin 12b on the surface in contact with the concave tooth forming surface of the disk-shaped workpiece (swinging gear 15) in the tooth groove direction of the swinging concave tooth 15b. It is an axis to be made. The third linear movement shaft is a reference position of the convex pin 12b that moves on the surface in contact with the concave tooth forming surface of the disk-shaped workpiece (oscillating gear 15) in a direction perpendicular to the second linear movement shaft. It is an axis to be made.

  The fourth rotation axis is an axis that rotates the reference position of the convex pin 12b around the first linear movement axis. The fifth rotation axis is an axis that rotates the reference position of the convex pin 12b around the third linear movement axis. The fourth rotation axis and the fifth rotation axis shown here are axes that rotate around the pin center point 12C of the convex tooth pin 12b. The sixth indexing shaft is an axis that coincides with the rotation center axis B (shown in FIGS. 1A and 1B) of the oscillating gear 15 and calculates the rotational phase of the oscillating gear 15.

(2.3) Coordinate transformation process (coordinate transformation means)
Here, the machine tool in the present embodiment is intended for a machine configuration having first to sixth axes. That is, the NC program in the present embodiment is represented by the three linear motion axes and the three rotation axes, similarly to the operation locus of the convex pin 12b described above. That is, in the coordinate conversion process, an NC program including three linear motion axes and three rotation axes is generated so as to perform substantially the same operation as the operation locus of the convex tooth pin 12b. This NC program includes a feed speed relative to the disk-shaped workpiece of the machining tool.

  In the machining process, machining is performed based on the NC program whose coordinates are converted in the coordinate conversion process. That is, as shown in FIG. 7, the first linear motion shaft, the second linear motion shaft, the third linear motion shaft, the fourth rotational shaft (around the pin center point 12C), and the fifth rotational shaft (around the pin center point 12C). The swinging concave teeth 15b are machined by relatively moving the disk-shaped workpiece and the processing tool by six axes including the sixth indexing shaft (around the rotation center axis B of the rocking gear 15). . That is, when the processing tool is a pin-shaped processing tool, the pin-shaped processing tool is moved so as to perform the same operation as that of the convex pin 12b. Further, in the case of a rotary belt-like tool, the linear portion of the tool is operated in the same manner as a pin-shaped machining tool.

(3) Processing tool Next, the processing tool in this embodiment is demonstrated with reference to FIG. As shown in FIG. 8, in the present embodiment, a toroidal grindstone 30 is used. However, it is not limited to the toroidal grindstone 30 as long as it is a processing tool that can express the outer peripheral shape of the convex pin 12b.

  As shown in FIG. 8B, the outer peripheral shape of the toroidal grindstone 30 is formed such that the axial center portion protrudes radially outward. And the axial direction cross-sectional shape of the shape of this protrusion part is made into semicircular arc shape. The swinging concave teeth 15 b are processed mainly by the protruding portion of the toroidal grindstone 30.

(4) Description of Feed Speed Control of the Present Embodiment Here, when machining the swinging concave tooth 15b as described above, the contact portion between the toroidal grindstone 30 and the disk-shaped workpiece (“machining with a tool of the present invention”). Corresponds to the “region”), which changes in a complex manner at each moment during processing. For example, at a certain moment, the entire axial direction at the protruding portion of the toroidal grindstone 30 is machining a disk-shaped workpiece, or at another moment, only a part of the axial direction at the protruding portion of the toroidal grindstone 30 is a disk-shaped workpiece. Or processing. Further, when attention is paid to a certain moment during machining, the volume to be machined may be different in the machining area of the toroidal grindstone 30 that is in contact with the disk-shaped workpiece.

  When the toroidal grindstone 30 is moved relative to the disc-shaped workpiece in accordance with the feed rate of the NC program generated as described above, the processing burn is generated at a local portion of the disc-shaped workpiece with extremely high processing efficiency. May occur. Therefore, the local portion of the toroidal grindstone 30 is locally observed so as to grasp which local portion has the degree of processing efficiency. And all of the processing efficiency for every local site | part is below a setting upper limit, Comprising: The disk shape of the toroidal grindstone 30 so that the maximum value in the processing efficiency of a local site | part becomes more than a setting lower limit. The feed rate relative to the workpiece is changed.

  Therefore, first, the processing area by the toroidal grindstone 30 is divided into a plurality of minute areas. Here, as shown in FIGS. 8A and 8B, the position coordinates of each part of the outer peripheral surface of the toroidal grindstone 30 are the position w on the grindstone surface in the axial section (hereinafter referred to as the “surface position w of the axial section”). And the rotational phase θ. That is, the reference point w0 of the surface position w of the axial section and the reference point θ0 of the rotational phase θ are as shown in FIGS. 8 (a) and 8 (b). And the micro area | region dA with the process area | region (outer peripheral surface) by the toroidal grindstone 30 is as showing to Fig.9 (a) (b). That is, each minute region dA is determined by the minute width dw of the surface position w of the axial cross section of the toroidal grindstone 30, the minute phase dθ of the rotational phase θ of the toroidal grindstone 30, and the radius r (w) of the toroidal grindstone 30 at the position w. Can be represented.

  Here, the overall machining efficiency at time t (hereinafter, referred to as “total machining efficiency”) Q (t) is expressed by Expression (1). In the formula (1), Q ″ (w, θ, t) is the machining efficiency in each minute region dA. Here, the machining efficiency corresponds to the machining volume per unit time. ), By integrating the machining efficiency Q ″ (w, θ, t) of all the minute regions at a certain time t with respect to the rotational phase θ and the surface position w of the axial section of the toroidal grindstone 30, The overall processing efficiency Q (t) can be obtained.

  Further, the machining efficiency Q ″ (w, θ, t) in the minute region is expressed by the area dA of the minute region and the feed rate vector F (relative to the workpiece of the toroidal grindstone 30 in the minute region at time t. w, θ, t) and the normal vector N (w, θ) in each minute region are expressed as shown in Equation (2). That is, the machining efficiency Q ″ (w, θ, t in the minute region ) Is obtained by multiplying the minute area dA by the normal direction component of the minute region at the feed rate F.

  FIG. 10 shows an example of the distribution of the machining efficiency Q ″ (w, θ, t) of each minute region at each of the times t1, t2, and t3. For example, the machining efficiency Q ″ ( w, θ, t1) shows the maximum value Q ″ max (t1) when the surface position w of the axial cross section of the toroidal grindstone 30 is slightly w = 0 from the vicinity of the center. The processing efficiency Q ″ (w, θ, t2) of the region shows the maximum value Q ″ max (t2) when the surface position w of the axial cross section of the toroidal grindstone 30 is near the center. Processing of the micro region at time t3 The efficiency Q ″ (w, θ, t3) also shows the maximum value Q ″ max (t3) when the surface position w of the axial cross section of the toroidal grindstone 30 is slightly w = 0 from the vicinity of the center. The machining efficiency Q ″ (w, θ, t3) of the minute region at time t3 shows a maximum value when the surface position w of the axial cross section of the toroidal grindstone 30 is slightly on the w = W side from the vicinity of the center. The

  The maximum value Q "max (t1) of the machining efficiency Q" (w, θ, t1) of the micro area at time t1 is the maximum value of the machining efficiency Q "(w, θ, t2) of the micro area at time t2. The maximum value Q "max (t2) is larger than Q" max (t2), and the maximum value Q "max (t2) is larger than the maximum value Q" max (t3) of the processing efficiency Q "(w, θ, t3) of the minute region at time t3. As described above, when the times are different, the maximum value Q ″ max (t) of the processing efficiencies Q ″ (w, θ, t) of the minute regions at the respective times is different.

  In this way, the disk shape of the toroidal grindstone 30 is such that all of the machining efficiency Q ″ (w, θ, t) in each divided minute region is equal to or less than the set upper limit value Q ″ set1, as shown in FIG. The feed rate relative to the workpiece is changed. For example, the relationship between the corrected feed rate Fn (t) and the uncorrected feed rate F0 (t) is expressed as shown in Equation (3). As a result, the maximum value of the machining efficiency Q ″ (w, θ, t) in the minute region can be set to the set upper limit value Q ″ set1 or less, so that even when viewed locally, the occurrence of machining burn can be prevented. .

  Further, with respect to the disc-shaped workpiece of the toroidal grindstone 30 such that the maximum value of the machining efficiency Q ″ (w, θ, t) in each divided minute region is equal to or larger than the set lower limit value Q ″ set2, as shown in FIG. The relative feed rate will be changed. That is, the relationship between the corrected feed rate Fn (t) and the corrected feed rate F0 (t) is expressed as in equation (4). Thereby, since processing efficiency can be set as high as possible, the prolongation of processing time can be prevented.

  Here, in order to satisfy the above equations (3) and (4), the set upper limit value Q "set1 and the set lower limit value Q" set2 may be set to the same value. When the set value in this case is Q "set, the relationship between the corrected feed rate Fn (t) and the uncorrected feed rate F0 (t) is expressed by equation (5). Thereby, even when viewed locally, the occurrence of work burn can be prevented, and the work time can be shortened as much as possible.

  In this way, the corrected feed speed Fn (t) is calculated at each time t. Then, the machine tool is controlled so that the feed speed at each time t becomes the corrected feed speed Fn (t). As described above, even when the swinging concave teeth 15b of the swinging gear 15 having a very complicated shape are processed, the processing time can be shortened as much as possible while preventing local processing burn. it can. That is, highly accurate machining can be realized while preventing the machining time from being prolonged.

<Second embodiment>
In the first embodiment, the machining efficiency Q ″ (w, θ, t) in the micro region has been described using the rotational phase θ and the surface position w of the axial section as parameters. The calculation process is very complicated to calculate w, θ, t). Therefore, a method that can more simply calculate the machining efficiency in a minute region will be described below.

  However, since a condition is required to perform the simple calculation, the condition will first be described with reference to FIG. In the processing region where the workpiece 15 is processed by the toroidal grindstone 30, the range in the rotational phase θ direction of the toroidal grindstone 30 is very small. When actually trying to process with high accuracy, the rotational phase θ in contact with the toroidal grindstone 30 becomes very small. If it does so, as shown in FIG. 12, the micro area | region by the toroidal grindstone 30 in each moment during processing can be considered as plane P shape. Then, the feed velocity vector F (w, θ, t) and the normal vector N (w, θ) in each minute region are simplified to a relational expression that does not use the rotational phase θ as a parameter as shown in Expression (6). it can.

  Furthermore, when the relative movement direction of the toroidal grindstone 30 with respect to the work piece 15 includes almost no rotational motion and can be regarded as a linear motion, the feed speed vector F (w, θ, As in equation (7), t) can be simplified to a relational expression that does not use the surface position w of the axial section as well as the rotational phase θ as a parameter.

  When the above condition is satisfied, the machining efficiency Q ′ (w, t) in the minute region can be expressed as in Expression (8).

  Here, in the toroidal grindstone 30, the contact arc length L with the workpiece 15 at the surface position w of the axial cross section is a radial cross section passing through the surface position w of the axial cross section of a certain toroidal grindstone 30 as shown in FIG. In the shape, it is the length in the circumferential direction in contact with the workpiece 15. For example, at a certain time t, the contact range between the toroidal grindstone 30 and the workpiece 15 in the two-dimensional coordinates of the surface position w of the axial section of the toroidal grindstone 30 and the rotational phase θ of the toroidal grindstone 30 is shown in FIG. Suppose that it is an enclosed range as shown in a). In this case, the contact arc length L1 at the surface position w1 of the axial cross section is the length shown in FIG. That is, the contact arc length L1 varies depending on the surface position w of the axial cross section. If it does so, in the case of a contact range as shown to Fig.13 (a), it represents like FIG.13 (b).

  In this way, by simplifying on the premise of the above conditions, the machining efficiency Q ′ (w, t) of a minute region at a certain time t can be calculated very easily. Then, when the machining efficiency Q ′ (w, t) of each minute region at each of the times t1, t2, and t3 is calculated, an example of the distribution is as shown in FIG. The parameters are the surface position w and the time t of the axial section, and can be represented by two-dimensional coordinates. Then, the maximum values Q′max (t1), Q′max (t2), and Q′max (t3) at times t1, t2, and t3 are also as shown in FIG.

  Here, in the second embodiment, the setting upper limit value and the setting lower limit value described in the first embodiment will be described as the same value Q′set. Then, as shown in FIG. 15, the feed speed Fn (so as to coincide with the maximum values Q′max (t1), Q′max (t2), and Q′max (t3) at each of the times t1, t2, and t3. t) is corrected.

  That is, the relationship between the corrected feed rate Fn (t) and the corrected feed rate F0 (t) is expressed as shown in Equation (9). As a result, the arithmetic processing is facilitated, and even when viewed locally, the occurrence of processing burn can be prevented, and the processing time can be shortened as much as possible.

<Third embodiment>
Next, in the third embodiment, in addition to the second embodiment, when calculating the machining efficiency Q ′ (w, t) in a micro region, the coefficient C (w, t) representing the difficulty of reaching the coolant ). Here, when performing a grinding process or a cutting process, a coolant is used in order to reduce heat generated by the process or to perform a process with high accuracy. Depending on the shape of the workpiece and the shape of a tool such as a grindstone, there are sites where the coolant can easily reach and sites where the coolant is difficult to reach. In the part where the coolant is difficult to reach, the cooling performance is low compared to the part where the coolant is easy to reach. Work burn may occur. Therefore, in the present embodiment, the machining efficiency Q ′ (w, t) in the minute region is corrected using the coefficient C (w) representing the difficulty of reaching the coolant.

  Specifically, the machining efficiency Qc ′ (w, t) in the micro area after correction is expressed as shown in Expression (10). Here, the coefficient C (w) is a function using the surface position w of the axial section as a parameter, assuming that the difficulty of reaching the coolant varies depending on the surface position w of the axial section.

  In this case, at each of the times t1, t2, and t3, the maximum values Q'max (t1), Q'max (t2), and Q 'of the times t1, t2, and t3 described in the second embodiment. max (t3) is corrected to the maximum values Qc′max (t1), Qc′max (t2), and Qc′max (t3) as indicated by the broken line in FIG. In the example illustrated in FIG. 16, the central portion of the surface position w of the axial cross section is illustrated as a portion where the coolant does not easily reach. In this way, considering the difficulty of reaching the coolant, the processing time can be shortened as much as possible while preventing the occurrence of local processing burn more reliably.

<Fourth embodiment>
Next, in the present embodiment, a specific configuration for realizing the above-described embodiment will be described with reference to FIG. As shown in FIG. 17, the feed speed control device of the present embodiment includes an NC program generation device 110, an NC device 120, and various information storage units 131 to 134.

  The NC program generation device 110 corresponds to a so-called CAM, and generates an NC program by inputting a material shape, a product shape, processing conditions, and the like. This NC program contains information on the relative feed rate of the tool to the workpiece.

  The NC device 120 is a control device that inputs an NC program and controls a machine tool. The NC device 120 includes a feed speed correction unit 121, an interpolation processing unit 122, and a control unit 123. The feed speed correction unit 121 corrects the feed speed included in the input NC program. Since this correction method is as described in the first to third embodiments, a detailed description is omitted. This correction is performed using machine information 131, tool information 132, work piece information, and set value information 134. The set value information 134 includes a set lower limit value Q "set1, a set upper limit value Q" set2, and the like.

  Subsequently, the interpolation processing unit 122 of the NC device 120 interpolates the feed speed corrected by the feed speed correction unit 121 to the feed speed for controlling the actual machine tool, using various stored information. ing. For example, the feed rate in the NC program is interpolated so as to change continuously and smoothly. Subsequently, the control unit 123 of the NC device 120 controls a servo motor (not shown) for each axis of the machine tool based on the corrected and interpolated NC program.

<Fifth embodiment>
Next, in this embodiment, it is set as the structure which reversed the order of the feed speed correction | amendment part and the interpolation process part with respect to 4th embodiment. Here, in 5th embodiment, about the same structure as 4th embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  That is, as shown in FIG. 18, the feed rate control device of this embodiment includes an NC program generation device 110, an NC device 220, and various information storage units 131 to 134. The NC device 220 includes an interpolation processing unit 221, a feed speed correction unit 222, and a control unit 123.

  The interpolation processing unit 221 of the NC device 220 interpolates the feed rate included in the NC program generated by the NC program generation device 110 to the feed rate for controlling the actual machine tool using various stored information. To do. Subsequently, the feed speed correction unit 222 corrects the feed speed interpolated by the interpolation processing unit 221. Since this correction method is as described in the first to third embodiments, a detailed description is omitted. The above-described interpolation and correction are performed using the machine information 131, the tool information 132, the workpiece information 133, and the set value information 134.

<Sixth embodiment>
Next, in the present embodiment, a feed speed correction unit is included in the NC program generation device, not in the NC device, as compared with the fourth embodiment. Here, in the sixth embodiment, the same components as those in the fourth embodiment are denoted by the same reference numerals and description thereof is omitted.
As shown in FIG. 18, the feed rate control device of the present embodiment includes an NC program generation device 310, an NC device 320, and various information storage units 131 to 134.

  The NC program generation device 310 includes an NC program generation unit 311 corresponding to the NC program generation device 110 in the fourth embodiment. The NC program generation unit 311 corresponds to a so-called CAM, and generates an NC program by inputting a material shape, a product shape, processing conditions, and the like. This NC program contains information on the relative feed rate of the tool to the workpiece.

  Furthermore, the NC program generation device 310 includes a feed speed correction unit 312 that corrects the feed speed included in the NC program generated by the NC program generation unit 311. Since this correction method is as described in the first to third embodiments, a detailed description is omitted. This correction is performed using machine information 131, tool information 132, work piece information, and set value information 134.

  The NC device 320 includes an interpolation processing unit 321 and a control unit 322. The interpolation processing unit 321 interpolates the feed rate of the NC program input from the NC program generation device 310 to the feed rate for controlling the actual machine tool using various stored information. For example, the feed rate in the NC program is interpolated so as to change continuously and smoothly. Subsequently, the control unit 322 controls a servo motor (not shown) for each axis of the machine tool based on the interpolated NC program.

<Seventh embodiment>
In the above embodiment, the case of the oscillating gear of the oscillating gear device has been described as the object to be processed. The oscillating gear device is configured to have two sets of relations between the concave and convex gears and the counter gears that intersect with each other. A power transmission device having a configuration having one set of the relationship between the concave and convex gears and the mating gear will be described with reference to FIGS.
20A shows a case where the convex tooth pin 112b is formed separately from the input shaft main body 112a. FIG. 20B shows a case where the convex tooth pin 112b is formed by the input shaft main body 112a. The case where it is integrally formed with respect to is shown.

  As shown in FIGS. 20A and 20B, the power transmission device includes an input shaft 112 and an output shaft 115. The input shaft 112 (corresponding to the “counter gear” of the present invention) has a configuration substantially similar to that of the output shaft 13 in the first embodiment. The input shaft 112 includes an input shaft main body 112a and a plurality of convex tooth pins 112b. The input shaft main body 112a is a cylindrical member having an axis A as a rotation center axis. The input shaft main body 112a is supported so as to be rotatable around the rotation center axis A with respect to a housing (not shown) via a bearing.

  The output shaft 115 (corresponding to the “concave gear” of the present invention) has substantially the same end face shape as one of the inner rings (oscillating gears) 15 in the first embodiment. That is, a plurality (G2) of concave teeth 115b are formed at equal intervals in the circumferential direction on one end surface of the output shaft 115 in the axial direction (left side in FIGS. 20A and 20B). The output shaft 115 is supported by a housing (not shown) via a bearing so as to be rotatable about a rotation center axis B inclined with respect to the rotation center axis A. And the other axial direction of output shaft 115 (the right side of Drawing 20 (a) (b)) is connected with other power transmission members.

  As described above, when the concave teeth of the output shaft 115 that rotates about the rotation center axis B that intersects the rotation center axis A of the input shaft 112 are processed, the feed speed control method according to the above-described embodiment and The device can be applied as well. And the same effect is produced.

<Eighth embodiment>
The feed rate control in the present embodiment is performed so that the total value Q _A (t) of the axial direction component force of the toroidal grindstone 30 is equal to or less than the set value Q _A set and the radial direction component force of the toroidal grindstone 30 is controlled. The feed speed of the toroidal grindstone 30 is controlled so that the total value Q _R (t) is equal to or less than the set value Q _R set. Hereinafter, this will be described in detail with reference to FIG.

First, the total value Q _A (t) of the forces in the axial direction component of the toroidal grindstone 30 is expressed by Expression (11). The axial direction of the toroidal grindstone 30 is the axial direction of the toroidal grindstone 30. In Formula (11), Q ″ (w, θ, t) is the machining efficiency in each minute region dA described in the above embodiment. That is, according to Formula (11), the machining efficiency Q at a certain time t. "(w, θ, t) is multiplied by the axial direction component V _A (w, θ) in the normal direction unit vector N (w, θ) of the minute region, and the machining region by the toroidal grindstone 30 is obtained for the multiplied value By performing the integration over a period of time, it is possible to obtain the total value Q _A (t) of the axial component force applied to the toroidal grindstone 30 at a certain time t. FIG. 21 shows the normal direction unit vector N (w, θ) of the minute region and the axial direction component V _A (w, θ) in the normal direction unit vector N (w, θ) of the minute region. .

Further, the total value Q _R (t) of the radial component of the toroidal grindstone 30 is expressed by the equation (12). The radial direction of the toroidal grindstone 30 is the axial direction of the toroidal grindstone 30. In Expression (12), Q ″ (w, θ, t) is the machining efficiency in each minute region dA described in the above embodiment. That is, according to Expression (12), the machining efficiency Q at a certain time t. “(w, θ, t) is multiplied by the radial direction component V _R (w, θ) in the normal direction unit vector N (w, θ) of the minute area, and the machining area by the toroidal grindstone 30 is obtained for the multiplied value By performing the integration over a period of time, it is possible to obtain a total value Q _R (t) of the radial component force applied to the toroidal grindstone 30 at a certain time t. FIG. 21 shows the radial direction component V _R (w, θ) in the normal direction unit vector N (w, θ) of the minute region.

The total value Q _A (t) of the forces in the axial direction component of the toroidal grindstone 30 and the total value Q _R (t) of the forces in the radial direction component of the toroidal grindstone 30 calculated in this way are the upper limit of each setting. The relative feed speed of the toroidal grindstone 30 with respect to the disk-shaped workpiece is changed so that the values are equal to or less than the values Q _A set and Q _R set. For example, the relationship between the corrected feed rate Fn (t) and the uncorrected feed rate F0 (t) is a relationship represented by equations (13) and (14).

According to the present embodiment, by using the machining efficiency Q ″ (w, θ, t) of each minute region, the total value Q _A (t), the force of the axial direction component or the radial direction component applied to the toroidal grindstone 30 is obtained. Q _R (t) can be calculated, and feed rate control is performed so that the total value Q _A (t), Q _R (t) of these forces is below the set upper limit value Q _A set, Q _R set Thereby, it can be set as the suitable feed rate according to the support rigidity of the toroidal grindstone 30 with respect to the force of an axial direction component or a radial direction component.

  Note that the processing efficiency of the micro region can be calculated by the method described in the first embodiment described above, or can be calculated by the simplified method described in the other embodiments.

11: input shaft 11a: inclined surface 12: fixed shaft 12a: fixed shaft main body 12b: convex tooth pin 12C: pin center point 12X: reference shaft 13: output shaft 13a: output shaft main body 13b: convex tooth Pin 14: Outer ring 15: Inner ring (oscillating gear), 15a: Rolling surface, 15b, 15c: Oscillating concave tooth 15X: Tooth groove direction 16: Rolling element 30: Toroidal grindstone

Claims (12)

In a feed rate control method for controlling a relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool,
The feed speed is controlled so that the machining efficiency in each of the micro regions is equal to or lower than a set upper limit when the machining region by the tool at each moment during machining is divided into a plurality of micro regions. Speed control method. In claim 1,
A feed rate control method, wherein the feed rate is controlled so that the maximum value of the machining efficiency of the minute region at each moment during machining is equal to or greater than a set lower limit value. In claim 1 or 2,
The workpiece is a concavo-convex gear in which concave teeth and convex teeth are continuously formed in the circumferential direction, and the concave teeth mesh with the convex teeth of the counter gear to transmit power to the counter gear. And a feed speed control method characterized by being a gear that rotates around a crossing axis that intersects the rotation center axis of the counter gear. In any one of Claims 1-3,
The tool is a disc-shaped grindstone that grinds the workpiece while rotating around a central axis,
2. The feed rate control method according to claim 1, wherein the minute region is a region obtained by dividing a processing region by the disc-shaped grindstone along a surface of an axial section of the disc-shaped grindstone. In claim 4,
When the minute area formed by the disc-shaped grindstone at each moment during machining is regarded as planar, and the relative movement direction of the disc-shaped grindstone at each moment during machining is regarded as a straight direction In addition,
The processing efficiency in the minute region is determined by the contact arc length with the workpiece at each position on the grindstone surface in the axial section of the disc-shaped grindstone, and the relative feed speed of the disc-shaped grindstone with respect to the workpiece. A feed speed control method comprising: calculating by multiplying the normal direction component of the minute area regarded as the planar shape in In any one of Claims 1-5,
According to the surface position of the tool, set a coefficient representing the difficulty of reaching the coolant,
The machining efficiency in the minute area is corrected by multiplying the basic machining efficiency calculated based on the area of the minute area and the feed speed of the tool in the minute area with respect to the workpiece by the coefficient. Feed rate control method, characterized in that In a feed rate control device that controls the relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool,
The feed speed is controlled so that the machining efficiency in each of the micro regions is equal to or lower than a set upper limit when the machining region by the tool at each moment during machining is divided into a plurality of micro regions. Speed control device. In claim 7,
The feed rate control device controls the NC machine tool based on the NC program, and the machining efficiency in each of the micro regions is equal to or less than a set upper limit value with respect to the feed rate of the tool to the workpiece in the NC program. A feed rate control device, characterized in that the feed rate control device is an NC device that controls the feed rate so corrected. In claim 7,
An NC program based on the feed speed calculated so that the machining efficiency in each of the micro areas is equal to or lower than a set upper limit value when the machining area by the tool at each moment during machining is divided into a plurality of micro areas. NC program generating device for generating
An NC device for controlling the relative feed rate of the workpiece of the tool based on the feed rate of the NC program and machining the workpiece with the tool;
A feed rate control device comprising: In a feed rate control method for controlling a relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool,
When the machining area by the tool at each moment during machining is divided into a plurality of minute areas, the machining efficiency in each minute area is calculated,
Multiplying the calculated machining efficiency in the micro area by a predetermined direction component in the normal direction unit vector of the micro area,
For the multiplication value, integration over the machining area by the tool,
A feed rate control method, wherein the feed rate is controlled so that the integral value is equal to or less than a set upper limit value. In claim 10,
The tool is a disc-shaped grindstone that grinds the workpiece while rotating around a central axis,
The feed rate control method, wherein the predetermined direction is at least one of a rotation axis direction of the disc-shaped grindstone and a direction orthogonal to the rotation axis of the disc-shaped grindstone. In a feed rate control device that controls the relative feed rate of the tool with respect to the workpiece when machining the workpiece with a tool,
When the machining area by the tool at each moment during machining is divided into a plurality of minute areas, the machining efficiency in each minute area is calculated,
Multiplying the calculated machining efficiency in the micro area by a predetermined direction component in the normal direction unit vector of the micro area,
For the multiplication value, integration over the machining area by the tool,
A feed speed control device that controls the feed speed so that the integral value is equal to or less than a set upper limit value.

Images