WO2023058107A1

WO2023058107A1 - Machining device

Info

Publication number: WO2023058107A1
Application number: PCT/JP2021/036792
Authority: WO
Inventors: 久修小林; 知也森; 淳司久原
Original assignee: 株式会社ジェイテクト
Priority date: 2021-10-05
Filing date: 2021-10-05
Publication date: 2023-04-13
Also published as: CN117940250A

Abstract

A machining device (1, 201) for machining a workpiece (W), which is supported by a workpiece supporting member (20, 30, 40, 60, 220, 230, 240), with a tool (T, T2), the machining device (1, 201) comprising a processing unit (3, 203) that controls machining, or estimates at least one of the state of the workpiece (W) or the tool (T, T2) during machining, the shape of the workpiece (W), the shape of the tool (T, T2), and a machine state of the machining device (1, 201), using contact dynamic stiffness data (Cwc, Kwc) between the workpiece (W) and the workpiece supporting member (20, 30, 40, 60, 220, 230, 240) provided by the contact between the workpiece (W) and the workpiece supporting member (20, 30, 40, 60, 220, 230, 240).

Description

processing equipment

The present disclosure relates to processing equipment.

Patent Document 1 describes a grinding simulation device. Grinding simulation calculates the removal amount of the workpiece based on the relative position of the workpiece and the grinding wheel, calculates the grinding resistance based on the removal amount, and calculates the correction amount of the relative position based on the grinding resistance. This is done by repeating In calculating the correction amount, the support stiffness for supporting the workpiece and the support stiffness for supporting the grinding wheel, which have been measured in advance, are used.

Patent Document 2 describes that when a workpiece is ground by a grinding wheel, the depth of the grinding marks on the workpiece is calculated by taking into consideration the contact static rigidity between the workpiece and the grinding wheel. there is The static contact stiffness used here is calculated using the theoretical static contact stiffness during grinding, not the value measured when the grinding wheel is stationary. Contact static stiffness is represented by the spring constant K between the workpiece and the grinding wheel.

JP 2018-153907 A JP 2015-208812 A

In the devices described in

Patent Documents

1 and 2, the support rigidity of the workpiece support member that supports the workpiece is considered. The rigidity of the support structure for the workpiece by the workpiece support member varies depending not only on the rigidity of the workpiece support member, but also on the state of contact between the workpiece and the workpiece support member. However, it has been found that the devices described in

Patent Literatures

1 and 2 do not consider the change in contact state, and an error occurs in the estimation result of the estimation target.

The present disclosure seeks to provide a processing apparatus that takes into account the state of contact between the workpiece and the workpiece support member and performs desired processing.

One aspect of the present disclosure is a processing apparatus for processing a workpiece supported by a workpiece support member with a tool,
Using contact dynamic stiffness data between the workpiece and the workpiece support member exerted by contact between the workpiece and the workpiece support member, machining is controlled, or the workpiece during machining Alternatively, the processing apparatus includes a processing unit that estimates at least one of the state of the tool, the shape of the workpiece, the shape of the tool, and the mechanical state of the processing apparatus.

According to the above aspect, the processing unit uses contact dynamic stiffness data between the workpiece and the workpiece support member to perform desired processing. The desired target process is a process of controlling machining, or a process of estimating at least one of the state of the workpiece or tool during machining, the shape of the workpiece, the shape of the tool, and the mechanical state of the processing device. is.

The contact dynamic stiffness data is represented by the spring constant and damping coefficient between the workpiece and the workpiece support member exerted by the contact between the workpiece and the workpiece support member. In this way, by using the contact dynamic stiffness data including the spring constant and the damping coefficient, desired processing can be performed with high accuracy.

As described above, according to the above aspect, it is possible to provide a processing apparatus that performs desired processing by considering the contact state between the workpiece and the workpiece support member.

It should be noted that the symbols in parentheses described in the claims indicate the correspondence with specific means described in the embodiments described later, and do not limit the technical scope of the present invention.

1 is a diagram showing a processing apparatus according to Embodiment 1; FIG. 3 is a functional block diagram of a processing estimation device that constitutes the processing device; FIG. FIG. 4 is a schematic diagram showing the state of interference between a workpiece and a grinding wheel during grinding. FIG. 4 is a diagram showing the shape of a workpiece in a grinding simulation by a group of radial line segments, and a diagram showing a state in which the workpiece shown by the radial line segments interferes with the outer peripheral line of the grinding wheel during grinding. be. FIG. 3 is a schematic diagram showing workpiece-side dynamic rigidity and tool-side dynamic rigidity in grinding. FIG. 4 is a diagram for explaining the relationship between a workpiece, a support member, and contact dynamic stiffness; It is a figure which shows the contact dynamic rigidity table acquired by actual measurement. FIG. 10 is a diagram showing a dynamic contact stiffness table obtained by actual measurement and interpolation processing; It is a figure which shows the processing apparatus of Embodiment 2. FIG. FIG. 4 is a schematic diagram showing workpiece-side dynamic rigidity and tool-side dynamic rigidity in cutting.

(Embodiment 1)
1. Configuration of Processing Apparatus 1 The processing apparatus 1 will be described with reference to FIG. The processing apparatus 1 is intended for a processing apparatus that performs grinding processing. The processing device 1 includes a grinder body 2 as a processing device body and a processing section 3 .

The grinding machine main body 2 rotates the workpiece W, rotates a grinding wheel T as a tool that is a rotating body, and rotates the grinding wheel T relative to the workpiece W in a direction intersecting the axis of the workpiece W. The outer peripheral surface or the inner peripheral surface of the workpiece W is ground by bringing the workpiece W closer to the surface. A table traverse type grinder, a wheelhead traverse type grinder, or the like can be applied to the grinder main body 2 . Further, a cylindrical grinder, a cam grinder, or the like can be applied to the grinder main body 2 .

In this embodiment, as shown in FIG. 1, the workpiece W is, for example, a shaft-shaped member. However, the workpiece W is not limited to an axial shape, and may be of any shape.

In this embodiment, the workpiece W includes, as an example, a shaft portion Wa as a non-processed portion and a plurality of processed portions Wb whose outer peripheral surface is to be ground. The processed portion Wb has, for example, a cylindrical outer peripheral surface coaxial with the shaft portion Wa. However, the workpiece W shown in FIG. 1 is only an example, and the grinder main body 2 can grind workpieces having various shapes. Further, the workpiece W has a spindle-side center hole Wc on one axial end face and a tailstock-side center hole Wd on the other axial end face.

The processing unit 3 includes a control device 3a that controls the grinder body 2, and a machining estimation device 3b that estimates an estimation target related to machining. The control device 3a can control the grinding process by controlling the grinder main body 2 . The machining estimating device 3b determines the state of the workpiece W or the grinding wheel T, the shape of the workpiece W, the shape of the grinding wheel T, the shape of the workpiece W, the shape of the grinding wheel T, and the mechanical state of the processing device 1 (grinding machine body 2 machine states). The machining estimating device 3b performs the estimation processing of the estimation target by inputting information used for grinding and performing a simulation.

The machining estimation device 3b can function as a simulation device independent of the grinder main body 2 and the control device 3a, or can function as a simulation device that operates in conjunction with the grinder main body 2 and the control device 3a. . In the former case, the machining estimation device 3b can determine the optimum grinding conditions without actually grinding the workpiece W, for example. In the latter case, the machining estimating device 3b processes in parallel with the grinding of the workpiece W by the grinder main body 2, for example, to correct the grinding conditions and to affect various controls. can operate. Also, the machining estimation device 3b can be an integrated system of the grinder main body 2 and the control device 3a.

2. Configuration of Grinding Machine Main Body 2 and Control Device 3a An example of the configuration of the grinding machine main body 2 and the control device 3a will be described in detail with reference to FIG. A table traverse type cylindrical grinder is taken as an example of the grinder main body 2 . That is, the grinding machine main body 2 is configured to move the workpiece W in the axial direction of the workpiece W and to move the grinding wheel T in the direction crossing the axis of the workpiece W. Further, in the present embodiment, the case where the grinder main body 2 grinds the cylindrical outer peripheral surface of the workpiece W with the grinding wheel T is taken as an example.

The grinder body 2 includes a bed 10, a table 20, a spindle device 30, a tailstock device 40, a grindstone base 50, and a rest device 60. The table 20, the spindle device 30, the tailstock device 40, and the rest device 60 function as workpiece support members that support the workpiece W. As shown in FIG. The grinding wheel head 50 functions as a tool support member that supports the grinding wheel T. As shown in FIG. That is, the grinder main body 2 grinds the workpiece W supported by the workpiece support member with the grinding wheel T supported by the tool support member. The grinder main body 2 may further include a sizing device (not shown). The grinder main body 2 can also be configured without the rest device 60 . The constituent elements of the grinder body 2 will be described in detail below.

The bed 10 is installed on the installation surface. The bed 10 has a long width (length in the Z-axis direction) on the front side in the X-axis direction (lower side in FIG. 1) and a short width on the rear side in the X-axis direction (upper side in FIG. 1). It is

The bed 10 has a Z-axis guide surface 11 extending in the Z-axis direction on the upper surface on the front side in the X-axis direction. Further, the bed 10 has a Z-axis drive mechanism 12 that drives along a Z-axis guide surface 11 . In this embodiment, the Z-axis driving mechanism 12 includes a ball screw mechanism 12a and a Z-axis motor 12b. A ball screw mechanism 12a extends parallel to the Z-axis guide surface 11, and a Z-axis motor 12b drives the ball screw mechanism 12a.

In order to drive the Z-axis drive mechanism 12, a Z-axis drive circuit and a Z-axis detector 12c (not shown) are provided. The Z-axis drive circuit includes an amplifier circuit and drives the Z-axis motor 12b. The Z-axis detector 12c is, for example, an angle detector such as an encoder in this embodiment, and detects the angle of the rotating shaft of the Z-axis motor 12b. It should be noted that the Z-axis drive mechanism 12 may employ a linear motor or the like instead of the configuration including the ball screw mechanism 12a.

The bed 10 also includes a guide surface 13 extending in a direction crossing the Z-axis direction on the upper surface on the back side in the X-axis direction. In this embodiment, the guide surface 13 is an X-axis guide surface extending in the X-axis direction orthogonal to the Z-axis. Further, the bed 10 is provided with an X-axis drive mechanism 14 that drives along the X-axis guide surface 13 . In the present embodiment, the X-axis driving mechanism 14 is provided with a ball screw mechanism 14a and an X-axis motor 14b. A ball screw mechanism 14a extends parallel to the X-axis guide surface 13, and an X-axis motor 14b drives the ball screw mechanism 14a.

In order to drive the X-axis drive mechanism 14, an X-axis drive circuit (not shown) and an X-axis detector 14c are provided. The X-axis drive circuit includes an amplifier circuit and drives the X-axis motor 14b. The X-axis detector 14c is, for example, an angle detector such as an encoder in this embodiment, and detects the angle of the rotating shaft of the X-axis motor 14b. The X-axis drive mechanism 14 can also employ a linear motor or the like instead of the configuration including the ball screw mechanism 14a.

The table 20 is formed in an elongated shape, and is supported by the Z-axis guide surface 11 of the bed 10 so as to be movable in the Z-axis direction (horizontal left-right direction). Also, the table 20 is fixed to the ball screw nut of the Z-axis ball screw mechanism 12a, and is moved in the Z-axis direction by rotational driving of the Z-axis motor 12b.

The spindle device 30 constitutes a workpiece support member. The spindle device 30 supports the workpiece W and drives the workpiece W to rotate. The spindle device 30 is arranged on one end side of the table 20 in the Z-axis direction. The spindle device 30 includes a spindle housing 31, a spindle 32, a spindle motor 33, a spindle center 34, a spindle detector 35, and a spindle drive circuit (not shown).

The spindle housing 31 is fixed on the table 20. The main shaft 32 is rotatably supported by the main shaft housing 31 via bearings. The spindle motor 33 drives the spindle 32 to rotate.

The spindle center 34 (corresponding to the support center) supports the end surface of the workpiece W at one end in the axial direction (the left end in FIG. 1). Specifically, the spindle center 34 supports the workpiece W in a state of being pressed in the axial direction against a spindle-side center hole Wc formed in the end surface of the workpiece W at one end in the axial direction. In this case, the spindle center 34 supports the spindle-side center hole Wc as one of the elements of the supported portion of the workpiece W. As shown in FIG.

The spindle center 34 is fixed to the spindle 32 and provided rotatably with respect to the spindle housing 31 . However, if the spindle device 30 is provided with a rotating member such as an unillustrated blade, the spindle center 34 is fixed to the spindle housing 31 so as to be non-rotatable with respect to the spindle housing 31 . Also good. Further, the spindle device 30 may be provided with a chuck for gripping the workpiece W instead of the spindle center 34 . The chuck is rotationally driven by being connected to the main shaft 32 .

The spindle detector 35 and the spindle drive circuit are provided to drive the spindle motor 33 . The spindle detector 35 is, for example, an angle detector such as an encoder in this embodiment, and detects the angle of the rotating shaft of the spindle motor 33 . The spindle drive circuit includes an amplifier circuit and drives the spindle motor 33 .

The tailstock device 40 constitutes a workpiece support member together with the spindle device 30 . The tailstock device 40 is arranged on the other end side of the table 20 in the Z-axis direction. The tailstock device 40 is provided movably on the table 20 in the Z-axis direction. The tailstock device 40 includes a tailstock center 41 and an adjustment mechanism 42 . When the grinder main body 2 grinds the inner peripheral surface of the workpiece W, the tailstock device 40 is unnecessary.

The tailstock center 41 (corresponding to the support center) supports the end surface of the other end in the axial direction of the workpiece W (the right end in FIG. 1). Specifically, the tailstock center 41 supports the workpiece W while being pressed in the axial direction against a tailstock-side center hole Wd formed in the end face of the other axial end of the workpiece W. As shown in FIG. In this case, the tailstock center 41 supports the tailstock-side center hole Wd as one of the elements of the supported portion of the workpiece W. As shown in FIG. The tailstock center 41 may be provided so as not to rotate, or may be provided so as to be rotatable.

Further, the tailstock center 41 may be positioned at a fixed position with respect to the workpiece W, or may be provided movably with respect to the workpiece W in the axial direction of the workpiece W. Also good. In the latter case, the tailstock center 41 may be configured so that the pressing force of the workpiece W in the axial direction can be adjusted. The pressing force may be controllable by means of adjusting spring force, means of adjusting fluid pressure, or the like.

In this embodiment, the tailstock device 40 is provided with an adjustment mechanism 42. The adjustment mechanism 42 is composed of, for example, a spring, and the tailstock center 41 is configured to exert a pressing force. Here, when the tailstock center 41 exerts a pressing force on the workpiece W, the spindle center 34 also exerts a pressing force on the workpiece W as a reaction. Specifically, the tailstock center 41 and the spindle center 34 are configured to be able to adjust the axial pressing force of the workpiece W against the workpiece W by the adjustment mechanism 42 . That is, the tailstock center 41 and the spindle center 34 are configured to be able to adjust the supporting force of the workpiece W by the adjustment mechanism 42 . Here, the pressing force against the workpiece W by the tailstock center 41 and the spindle center 34 can be adjusted by an actuator, or can be adjusted by the operator.

The grinding wheel head 50 includes a grinding wheel T, and drives the grinding wheel T to rotate. In addition to the grinding wheel T, the grinding wheel head 50 includes a grinding wheel body 51, a grinding wheel shaft 52, a grinding wheel motor 53, and a grinding wheel driving circuit (not shown).

The grinding wheel T is shaped like a disc. The grinding wheel T is used to grind the outer peripheral surface or the inner peripheral surface of the workpiece W. The grinding wheel T is configured by fixing a plurality of abrasive grains with a binder. As the abrasive grains, general abrasive grains made of ceramic materials such as alumina and silicon carbide, and superabrasive grains such as diamond and CBN are applied.

Binders include vitrified (V), resinoid (B), rubber (R), silicate (S), shellac (E), metal (M), electrodeposition (P), magnesia cement (Mg), and the like. . Further, the grinding wheel T has a structure having pores and a structure having no pores. Depending on the type of binder and the presence or absence of pores, the grinding wheel T may be elastically deformable or substantially non-elastically deformable. The elastic modulus of the elastically deformable grinding wheel T varies depending on the type of binder, the presence or absence of pores, the porosity, and the like.

The wheelhead main body 51 is formed, for example, in a rectangular shape in plan view, and is supported by the X-axis guide surface 13 of the bed 10 so as to be movable in the X-axis direction (horizontal front-back direction). The wheelhead main body 51 is fixed to the ball screw nut of the X-axis ball screw mechanism 14a, and is moved in the X-axis direction by the rotational drive of the X-axis motor 14b. The grinding wheel head main body 51 constitutes a tool support member that supports the grinding wheel T. As shown in FIG.

The grindstone shaft 52 is rotatably supported by the grindstone head main body 51 via bearings. A grinding wheel T is fixed to the tip of the grinding wheel shaft 52 , and the grinding wheel T rotates as the grinding wheel shaft 52 rotates. The grinding wheel motor 53 rotates the grinding wheel shaft 52 . A hydrostatic bearing, a rolling bearing, or the like is used as the bearing.

The grinding wheel motor 53 transmits rotational driving force to the grinding wheel shaft 52 via, for example, a belt. However, the grinding wheel motor 53 may be arranged coaxially with the grinding wheel shaft 52 . In general, the rotation speed of the grinding wheel T driven by the grinding wheel motor 53 is higher than the rotation speed of the workpiece W driven by the spindle motor 33 . The grinding wheel drive circuit is provided to drive the grinding wheel motor 53 . The grinding wheel drive circuit includes an amplifier circuit and drives the grinding wheel motor 53 .

The rest device 60 is provided on the upper surface of the bed 10 and constitutes a workpiece support member that supports the outer peripheral surface of the workpiece W as one of the elements of the supported portion of the workpiece W. The rest device 60 is configured to be able to adjust the pressing force against the outer peripheral surface of the workpiece W by, for example, including a spring or the like. That is, the rest device 60 is configured so that the rigidity value of the workpiece W can be adjusted. Here, the pressing force applied to the outer peripheral surface of the workpiece W by the rest device 60 can be adjusted by an actuator, or can be adjusted by the operator.

The control device 3a is a CNC (Computer Numerical Control) device and a PLC (Programmable Logic Controller) device that execute machining control. That is, the control device 3a controls the positions of the table 20 and the wheelhead 50 by driving the Z-axis driving mechanism 12 and the X-axis driving mechanism 14 as moving devices based on the grinding program. In other words, the control device 3a moves the workpiece W and the grinding wheel T relatively closer to each other and away from each other by controlling the positions of the table 20, the grinding wheel head 50, and the like. Further, the control device 3 a controls the spindle device 30 and the wheelhead 50 . That is, the control device 3a controls the rotation of the spindle 32 and the rotation of the grinding wheel T. As shown in FIG.

Further, when the axial pressing force on the workpiece W by the tailstock center 41 and the spindle center 34 can be adjusted by an actuator, the control device 3a controls the actuator to adjust the axial pressing force. can be adjusted. Further, when the radial pressing force exerted by the rest device 60 on the outer peripheral surface of the workpiece W can be adjusted by an actuator, the control device 3a adjusts the radial pressing force by controlling the actuator. can do.

3. Configuration of Manipulation Estimating Device 3b The configuration of the manipulating estimating device 3b will be described with reference to FIG. The machining estimation device 3b includes a command value acquisition unit 101, an estimation unit 102, a workpiece-side dynamic stiffness table storage unit 103, a grinding wheel-side dynamic stiffness table storage unit 104, a dynamic stiffness determination condition acquisition unit 105, a dynamic stiffness determination unit 106, A correction amount calculation unit 107 and an output unit 108 are provided.

The command value acquisition unit 101 acquires a command value for controlling the grinder body 2 in grinding. When the machining estimating device 3b is a simulation device independent of the grinding machine main body 2 and the control device 3a, the command value acquiring unit 101 inputs the grinding processing program and the configuration information of the grinding machine main body 2, A command value for controlling each part of the grinder main body 2 is generated by calculation. Further, when the machining estimating device 3b functions as a simulation device that operates in conjunction with grinding by the grinder main body 2 and the control device 3a, the command value acquisition unit 101 acquires the command value directly from the control device 3a. can do.

The estimating unit 102 performs a grinding simulation using the command value acquired by the command value acquiring unit 101 to obtain the state of the workpiece W or the grinding wheel T, the shape of the workpiece W, the grinding wheel At least one of the shape of T and the mechanical state of the grinder body 2 is estimated.

The state of the workpiece W includes, for example, the vibration state and temperature state of the workpiece W. The state of the grinding wheel T includes, for example, the vibration state and temperature state of the grinding wheel T, the grinding resistance generated in each part of the outer peripheral surface of the grinding wheel T, the sharpness of the grinding wheel T, and the state of the abrasive grains constituting the grinding wheel T. and so on. The state of abrasive grains includes, for example, the average protrusion amount of abrasive grains, the distribution of abrasive grains, and the like. The shape of the workpiece W includes a shape at an intermediate stage of grinding and a shape at the end of grinding. The shape of the grinding wheel T includes a shape at an intermediate stage of grinding and a shape at the end of grinding. The mechanical state of the grinder body 2 includes the vibration state, temperature state, and the like of the parts constituting the grinder body 2 .

In this embodiment, the estimating unit 102 sequentially changes the shape of the workpiece W through a grinding simulation, thereby obtaining the shape of the workpiece W, the state of the workpiece W, and the mechanical state of the grinder main body 2. As an example, consider a case where is an estimation target. In this embodiment, the grinding simulation is performed assuming that the grinding wheel T does not deform. The estimating section 102 can also estimate the grinding resistance generated for each portion of the outer peripheral surface of the grinding wheel T, in addition to the estimation target.

The estimation unit 102 includes an interference amount calculation unit 111 , a grinding efficiency calculation unit 112 , a grinding characteristic determination unit 113 and a grinding resistance calculation unit 114 .

The interference amount calculator 111 calculates the relative position between the workpiece W and the grinding wheel T, the shape of the outer peripheral surface of the workpiece W, and the outer periphery of the grinding wheel T obtained by using the command value acquired by the command value acquiring unit 101. The amount of interference between the workpiece W and the grinding wheel T is calculated based on the surface shape. The amount of interference corresponds to the amount of grinding in the radial direction of the workpiece W at each portion of the workpiece W in the circumferential direction. In other words, the amount of interference is the amount of removal of the workpiece W ground by the grinding wheel T, more specifically, the amount of removal in the radial direction of the workpiece W at each portion of the workpiece W in the circumferential direction. The amount of interference, as shown in FIG. 3, is the volume of the portion where the workpiece W and the grinding wheel T interfere (hatched area in FIG. 3: interference region).

The interference amount calculation unit 111 geometrically calculates the interference amount through arithmetic processing. Here, the interference amount calculator 111 stores the shape of the outer peripheral surface of the workpiece W and the shape of the outer peripheral surface of the grinding wheel T. FIG. As shown in the right part of FIG. 4, the outer peripheral surface shape of the workpiece W is represented by a plurality of radial line segment groups on the polar coordinates with the rotation center Ow of the workpiece W as the origin. That is, the interference amount calculation unit 111 calculates a plurality of points connecting the division points (white points in FIG. 4) on the outer peripheral surface obtained by dividing the workpiece W into equal angles (α) and the rotation center Ow (origin) of the workpiece W. A group of line segments is stored as the shape of the outer peripheral surface of the workpiece W. Division points indicated by white dots in FIG.

The interference amount calculator 111 calculates each line segment of the workpiece W and the line representing the shape of the outer peripheral surface of the grinding wheel T from the relative position (the distance between the axes) of the workpiece W and the grinding wheel T and the shape of the outer peripheral surface of the grinding wheel T. (black dots in FIG. 4). The interference amount calculator 111 stores the determined intersection point (black point in FIG. 4) as the shape of the outer peripheral surface of the workpiece W after the workpiece W has been removed by the grinding wheel T. FIG. In other words, the interference amount calculator 111 changes the shape of the outer peripheral surface of the workpiece W that is stored.

Then, the interference amount calculation unit 111 calculates the area of a triangle ΔOw-a1-a2 formed by adjacent points a1 and a2 among the points defining the outer peripheral surface shape of the workpiece W before removal and the origin Ow. The area of a triangle ΔOw-b1-b2 consisting of the points b1 and b2 (the intersection with the grinding wheel T) and the origin Ow is subtracted. The area after subtraction is calculated for all adjacent points that define the outer peripheral surface shape of the workpiece W.

Then, the interference amount calculation unit 111 integrates the areas after each subtraction, and multiplies the integrated total area by the thickness of the workpiece W to calculate the interference amount (removal amount). In the above description, the area of the portion to be removed is calculated by calculating the areas of the two types of triangles and calculating the difference between the areas. Alternatively, the area of the removed portion may be calculated by directly calculating the rectangle a1-a2-b1-b2.

As shown in FIG. 2 , the grinding efficiency calculator 112 calculates the grinding efficiency Z′ based on the interference amount calculated by the interference amount calculator 111 . The grinding efficiency Z' is calculated by calculating the amount of interference per unit time, that is, the volume of the workpiece W ground by the grinding wheel T in the unit time.

The grinding characteristic determination unit 113 determines the grinding characteristic kc based on the material of the workpiece W, the types of abrasive grains and binder of the grinding wheel T, the state of the outer peripheral surface of the grinding wheel T, and the like. The state of the outer peripheral surface of the grinding wheel T is expressed using an index representing, for example, the wear state and sharpness of the abrasive grains of the grinding wheel T. FIG. Here, the grinding characteristic determination unit 113 stores grinding characteristics in each state in advance through experiments, analyses, or the like.

The grinding resistance calculator 114 calculates the grinding resistance Fn in the normal direction (X-axis direction) of the outer peripheral surface of the workpiece W based on the grinding efficiency Z' and the grinding characteristics kc. The grinding resistance Fn is obtained by multiplying the grinding efficiency Z' by the grinding characteristic kc (Fn=kc*Z').

The grinding characteristic kc has a substantially linear relationship such that the grinding resistance Fn in the normal direction (X-axis direction) increases as the grinding efficiency Z' increases. The relationship of the grinding characteristic kc changes when, for example, the grinding wheel T wears. For example, when the grinding wheel T wears, the grinding resistance Fn in the normal direction increases with respect to the grinding efficiency Z'.

The workpiece-side dynamic rigidity table storage unit 103 stores dynamic rigidity data Cw and Kw regarding the workpiece W side when the workpiece W side and the grinding wheel T side are divided by using the machining part as a boundary. The workpiece-side dynamic rigidity table storage unit 103 includes a dynamic rigidity table storage unit 103a related to the workpiece W, a dynamic rigidity table storage unit 103b related to the workpiece support members (20, 30, 40, 60), and a contact dynamic rigidity table storage unit 103c. including.

The dynamic stiffness table storage unit 103a relating to the workpiece W stores dynamic stiffness data Cwa, Kwa of the workpiece W (hereinafter referred to as workpiece dynamic stiffness data). The workpiece dynamic stiffness data Cwa, Kwa can be acquired by, for example, known hammering of the workpiece W, FEM analysis, and the like. When there are multiple types of workpieces W to be ground, the dynamic stiffness table storage unit 103a stores workpiece dynamic stiffness data Cwa and Kwa for each of the multiple types of workpieces W. FIG.

The dynamic stiffness table storage unit 103b for the workpiece support members (20, 30, 40, 60) stores the dynamic stiffness data Cwb, Kwb (hereinafter referred to as support member dynamic stiffness data) of the workpiece support members (20, 30, 40, 60). ) is stored. The support member dynamic stiffness data Cwb and Kwb can be acquired by hammering, FEM analysis, etc., on each of the spindle device 30, the tailstock device 40, and the rest device 60, which constitute the workpiece support member.

When the grinder main body 2 is capable of setting up a plurality of types of work support members (20, 30, 40, 60), the dynamic rigidity table storage unit 103b stores a plurality of types of work support members (20, 60). 30, 40, 60) are stored. When the support member dynamic stiffness data Cwb and Kwb change according to the processing conditions and the like, the dynamic stiffness table storage unit 103b stores the correspondence relationship between the processing conditions and the support member dynamic stiffness data Cwb and Kwb. do.

The contact dynamic stiffness table storage unit 103c stores contact dynamic stiffness data Cwc, Kwc between the workpiece W and the workpiece support members (20, 30, 40, 60). Since the contact dynamic stiffness data Cwc and Kwc change according to the processing conditions and the like, the contact dynamic stiffness table storage unit 103c stores the correspondence relationship between the processing conditions and the contact dynamic stiffness data Cwc and Kwc.

The contact dynamic stiffness data Cwc, Kwc include contact dynamic stiffness data between the center holes Wc, Wd and the support centers 34, 41. If the grinder main body 2 has a chuck for gripping the workpiece W, the contact dynamic stiffness data Cwc, Kwc will include the contact dynamic stiffness data between the workpiece W and the chuck. Further, the contact dynamic stiffness data Cwc, Kwc include contact dynamic stiffness data between the outer peripheral surface of the workpiece W and the rest device 60 . If the grinder main body 2 does not have the rest device 60 , the contact dynamic stiffness data Cwc, Kwc do not include the contact dynamic stiffness data between the outer peripheral surface of the workpiece W and the rest device 60 .

The grinding wheel side dynamic stiffness table storage unit 104 stores dynamic stiffness data Ct and Kt (tool side dynamic stiffness data) on the grinding wheel T side when the work piece W side and the grinding wheel T side are divided by using the machining part as a boundary. memorize That is, the grinding wheel side dynamic stiffness table storage unit 104 stores the dynamic stiffness data Ct and Kt of the grinding wheel head 50 including the grinding wheel T. FIG. The grinding wheel dynamic stiffness table storage unit 104 stores grinding wheel dynamic stiffness data Ct and Kt for each type of grinding wheel T, for example.

In addition, when the grinding wheel T is supported by a hydrostatic bearing and the pressure of the hydrostatic bearing can be controlled, the grinding wheel side dynamic stiffness data Ct and Kt are calculated according to the pressure of the hydrostatic bearing. Data may change. Therefore, the grinding wheel side dynamic stiffness table storage unit 104 may store the damping coefficient Ct and the spring constant Kt according to the pressure of the hydrostatic bearing as the processing condition. When the dynamic stiffness data Ct and Kt change according to the machining conditions and the like, the grinding wheel dynamic stiffness table storage unit 104 stores the correspondence relationship between the machining conditions and the grinding wheel dynamic stiffness data Ct and Kt. .

The workpiece side dynamic stiffness (Cw, Kw) and the grinding wheel side dynamic stiffness (Ct, Kt) will be described with reference to FIG. The workpiece side dynamic stiffness (Cw, Kw) includes the workpiece W and is the workpiece W side dynamic stiffness regarding the table 20 , the spindle device 30 , the tailstock device 40 and the rest device 60 .

The workpiece-side dynamic rigidity (Cw, Kw) is the dynamic rigidity exerted when the workpiece W is supported by the spindle device 30, the tailstock device 40, and the rest device 60 as workpiece support members constituting the grinder body 2. is. Workpiece side dynamic stiffness (Cw, Kw) is defined by damping coefficient Cw and spring constant Kw. The damping coefficient Cw is a value that represents the relationship between the relative speed of the workpiece W with respect to the reference position of the grinder body 2 and the external force that the workpiece W receives. The spring constant Kw is a value that represents the relationship between the relative position of the workpiece W with respect to the reference position of the grinder body 2 and the external force that the workpiece W receives.

As shown in FIG. 5, the workpiece side dynamic stiffness (Cw, Kw) consists of workpiece dynamic stiffness (Cwa, Kwa), support member dynamic stiffness (Cwb, Kwb), workpiece W and workpiece support member ( 20, 30, 40, 60) and contact dynamic stiffness (Cwc, Kwc).

The contact dynamic stiffness (Cwc, Kwc) is the dynamic stiffness between the workpiece W and the workpiece support members (20, 30, 40, 60), which is the workpiece W and the workpiece support members (20, 30, 60). 40, 60). Contact dynamic stiffness (Cwc, Kwc) is defined by damping coefficient Cwc and spring constant Kwc. The damping coefficient Cwc is a value that represents the relationship between the relative speed between the workpiece W and the workpiece support members (20, 30, 40, 60) and the external force that the workpiece W receives. The spring constant Kwc is a value that represents the relationship between the relative position between the workpiece W and the workpiece support members (20, 30, 40, 60) and the external force that the workpiece W receives.

Here, the contact dynamic stiffness (Cwc, Kwc) differs depending on the adjustment factor relating to the support force of the workpiece support members (20, 30, 40, 60) and the factors of the workpiece W to be supported. The relationship between the contact dynamic stiffness (Cwc, Kwc), the supporting force adjusting element, and the supported portion of the workpiece W will be described with reference to FIG.

FIG. 6(a) shows a case where the workpiece W is a small-diameter shaft, and the sizes (opening diameters) of the spindle-side center hole Wc and the tailstock-side center hole Wd formed in both end surfaces of the workpiece W are small. indicates In FIG. 6(b), the workpiece W is a large-diameter shaft, and the sizes (opening diameters) of the spindle-side center hole Wc and the tailstock-side center hole Wd formed in both end surfaces of the workpiece W are large. indicate the case. The sizes of the center holes Wc and Wd use the opening diameters of the center holes Wc and Wd as indices.

In FIG. 6(a), the axial pressing force against the workpiece W by the spindle center 34 and the tailstock center 41 is F1. In FIG. 6(a), the radial pressing force of the rest device 60 against the outer peripheral surface of the workpiece W is F2. In FIG. 6(b), the axial pressing force on the workpiece W by the spindle center 34 and the tailstock center 41 is F11. In FIG. 6(b), the radial pressing force of the rest device 60 against the outer peripheral surface of the workpiece W is F12.

In FIGS. 6(a) and 6(b), the relationship between the pressing forces is F1<F11 and F2<F12. Further, the contact areas between the center holes Wc, Wd and the support centers 34, 41 are larger in FIG. 6(b) than in FIG. 6(a). Further, the contact area between the outer peripheral surface of the workpiece W and the rest device 60 is larger in FIG. 6(b) than in FIG. 6(a).

Here, the contact dynamic stiffness (Cwc, Kwc) changes depending on the forces that the contacting members press against each other. The contact state between the center holes Wc and Wd of the work piece W and the support centers 34 and 41 changes due to changes in the axial pressing force exerted on the work piece W by the spindle center 34 and the tailstock center 41. changes, the dynamic contact stiffness (Cwc, Kwc) changes. In addition, the contact state between the outer peripheral surface of the workpiece W and the rest device 60 changes due to the change in the radial pressing force applied to the workpiece W by the rest device 60, and the contact dynamic stiffness (Cwc, Kwc) changes.

In a configuration in which the workpiece W is gripped by the chuck, the contact state between the workpiece W and the chuck changes due to changes in the gripping force of the chuck with respect to the workpiece W, and contact movement occurs as the contact state changes. The stiffness (Cwc, Kwc) changes.

Furthermore, the contact dynamic stiffness (Cwc, Kwc) also changes depending on the contact area. The difference in the size of the spindle-side center hole Wc and the size of the tailstock-side center hole Wd, which are elements of the supported portion, changes the contact area, and the contact dynamic stiffness is caused by the change in the contact area. (Cwc, Kwc) changes. In addition, the contact area changes due to the difference in the size of the support surface of the rest device 60 and the outer diameter of the workpiece W, and the contact dynamic stiffness (Cwc, Kwc) changes as the contact area changes. .

In addition, in a configuration in which the workpiece W is gripped by the chuck, the contact area between the workpiece W and the chuck changes due to the difference in the size of the gripping surface of the chuck and the gripping diameter of the workpiece W. changes, the dynamic contact stiffness (Cwc, Kwc) changes.

As shown in FIG. 5, the grinding wheel side dynamic stiffness is the dynamic stiffness related to the grinding wheel T and the grinding wheel head 50 . Grinding wheel side dynamic stiffness is defined by damping coefficient Ct and spring constant Kt. The damping coefficient Ct is a value that represents the relationship between the relative speed of the grinding wheel T with respect to the reference position on the grinding wheel head 50 and the external force that the grinding wheel T receives. The spring constant Kt is a value that represents the relationship between the relative position of the grinding wheel T with respect to the reference position on the grinding wheel head 50 and the external force that the grinding wheel T receives. The grinding wheel side dynamic stiffness (Ct, Kt) is the dynamic stiffness (Cta, Kta) of the grinding wheel T and the dynamic stiffness (Ctb, Ktb) exerted when the grinding wheel T is supported by the grinding wheel head main body 51. including.

The contact dynamic stiffness table storage unit 103c will be described in detail with reference to FIGS. 7 and 8. FIG. The contact dynamic stiffness table storage unit 103c stores a contact dynamic stiffness table including contact dynamic stiffness data Cwc, Kwc. Specifically, as shown in FIG. 7, the dynamic contact stiffness table includes conditions A1, A2, and A3 for adjustment elements relating to the supporting force of the workpiece W, and conditions for elements of the supported portion of the workpiece W. It is a table containing contact dynamic stiffness data Cwc and Kwc corresponding to B1, B2 and B3. The contact dynamic stiffness table may be a table including mass M in addition to damping coefficient Cwc and spring constant Kw.

　In FIG. 7, the adjustment elements related to the support force of the workpiece W are the adjustment elements related to the support force of the workpiece W by the workpiece support members (20, 30, 40, 60). For example, the supporting force adjustment element includes the center pressing force by the spindle center 34 and the tailstock center 41 . Further, the supporting force adjustment element includes the pressing force by the rest device 60 . Therefore, the conditions A1, A2, and A3 for the adjustment elements of the supporting force are conditions in which the center pressing force and the rest pressing force are changed.

Note that if the rest device 60 is not provided, the rest pressing force is not considered. Further, when the workpiece support member is a chuck that grips the workpiece W and is configured to be able to adjust the gripping force, the adjusting element related to the supporting force of the workpiece W is the gripping force of the chuck. becomes.

In addition, in FIG. 7, the elements of the supported portion of the workpiece W are the elements of the portion of the workpiece W that come into contact with the spindle center 34, the tailstock center 41, and the rest device 60. For example, the elements of the supported portion of the workpiece W include the sizes (opening diameters) of the center holes Wc and Wd. The element of the supported portion of the workpiece W includes the area of the portion of the outer peripheral surface of the workpiece W that contacts the rest device 60 (rest contact area). The rest contact area varies depending on the configuration of the rest device 60, the outer diameter of the workpiece W, and the like. Therefore, the conditions B1, B2, B3 for the elements of the supported portion of the workpiece W are conditions in which the size of the center holes Wc, Wd and the rest contact area are changed.

Note that if the rest device 60 is not provided, the rest contact area is not considered. Further, when the workpiece supporting member is a chuck that grips the workpiece W, the element of the supported portion of the workpiece W is the gripping area of the chuck.

The contact dynamic stiffness table shown in FIG. 7 is a data table obtained by actually measuring the first conditions (conditions A1, A2, A3 and conditions B1, B2, B3). It becomes a table limited to one condition.

However, since there are a wide variety of conditions that are actually used, the dynamic contact stiffness table shown in FIG. 7 may not be sufficient. Therefore, the hatched portion in FIG. 8 is supplemented by performing interpolation processing using the contact dynamic stiffness table obtained by actual measurement.

That is, as a premise, as shown in FIG. 7, the contact dynamic stiffness table storage unit 103c stores the first conditions (conditions A1, A2, A3 and conditions B1, B2, B3) and the actually measured contact dynamic stiffness data Cwc , Kwc is stored in advance. Then, by performing interpolation processing using the contact dynamic stiffness data Cwc, Kwc for the first conditions (conditions A1, A2, A3, and conditions B1, B2, B3), a second condition different from the first condition Contact dynamic stiffness data Cwc, Kwc for (conditions A1h, A2h and conditions B1h, B2h) are generated. The contact dynamic stiffness table storage unit 103c additionally stores the generated contact dynamic stiffness data Cwc and Kwc.

The interpolation process can use, for example, an empirical formula that defines the relationship between the supporting force adjustment element of the workpiece W, the element of the supported portion of the workpiece W, the damping coefficient Cwc, and the spring constant Kwc. Also, the interpolation processing may use machine learning, theoretical calculation, or the like.

As shown in FIG. 2, the dynamic stiffness determining condition acquisition unit 105 acquires the dynamic stiffness determining condition when performing the grinding process with the grinder body 2 . Specifically, the dynamic stiffness determination condition acquisition unit 105 acquires the dynamic stiffness determination condition at the time of estimation by the estimation unit 102 (at the time of processing). The dynamic stiffness determination condition acquired by the dynamic stiffness determination condition acquisition unit 105 is information used by the dynamic stiffness determination unit 106 to calculate each dynamic stiffness. The dynamic stiffness determination conditions to be acquired include, for example, the type of workpiece W, the type of workpiece support member, the type of grinding wheel T, the pressing force by the support centers 34 and 41, the pressing force by the rest device 60, and the like.

When the machining estimating device 3b is a simulation device independent of the grinder main body 2, the dynamic stiffness determination condition acquisition unit 105 inputs the mechanical configuration of the grinder main body 2 and the grinding program to obtain the dynamic stiffness Get the conditions for determining Further, when the machining estimating device 3b functions as a simulation device that operates in conjunction with grinding by the grinder body 2, the dynamic stiffness determination condition acquisition unit 105 obtains the mechanical configuration of the grinder body 2 from the control device 3a. and the conditions for determining the dynamic stiffness may be obtained by inputting a grinding program, or information on the conditions may be obtained directly from the control device 3a of the grinder main body 2. FIG.

The dynamic stiffness determination unit 106 determines dynamic stiffness data that affects the grinding process. The dynamic stiffness determining unit 106 separately determines the workpiece side dynamic stiffness data Cw, Kw and the grinding wheel side dynamic stiffness data Ct, Kt. That is, the dynamic stiffness determining section 106 includes a workpiece side dynamic stiffness determining section 121 and a grinding wheel side dynamic stiffness determining section 122 .

The workpiece side dynamic stiffness determination unit 121 corresponds to the type of workpiece W acquired by the dynamic stiffness determination condition acquisition unit 105 from the dynamic stiffness table stored in the dynamic stiffness table storage unit 103a regarding the workpiece W. Workpiece dynamic rigidity data Cwa, Kwa are determined. Further, the workpiece-side dynamic stiffness determination unit 121 selects the dynamic stiffness determination condition acquisition unit 105 from the dynamic stiffness table stored in the dynamic stiffness table storage unit 103b regarding the workpiece support members (20, 30, 40, 60). Determine the support member dynamic stiffness data Cwb and Kwb corresponding to the type of workpiece support member acquired in .

Furthermore, the workpiece-side dynamic stiffness determination unit 121 acquires conditions for determining the contact dynamic stiffness data Cwc, Kwc from the dynamic stiffness determination condition acquisition unit 105 . Then, the workpiece-side dynamic stiffness determining unit 121 acquires the supporting force adjustment elements and the elements of the supported portion of the workpiece W, as shown in FIGS. 7 and 8 . The workpiece-side dynamic stiffness determination unit 121 selects the contact dynamic stiffness table stored in the contact dynamic stiffness table storage unit 103c, the supporting force adjustment element, and the contact stiffness corresponding to the element of the supported portion of the workpiece W. Determine the dynamic stiffnesses Cwc and Kwc.

The grinding wheel dynamic stiffness determination unit 122 selects the type of grinding wheel T acquired by the dynamic stiffness determination condition acquisition unit 105 from the grinding wheel dynamic stiffness table stored in the grinding wheel dynamic stiffness table storage unit 104. Determine the corresponding dynamic stiffness data Ct, Kt.

A correction amount calculation unit 107 calculates a correction amount for relative displacement of the grinding wheel T and the workpiece W in the X-axis direction due to the grinding force Fn based on each dynamic rigidity data determined by the dynamic rigidity determination unit 106. calculate. A correction amount for displacement can be obtained from each dynamic rigidity data and the grinding force Fn. That is, the correction amount for the displacement can be calculated from the grinding force Fn, the workpiece side dynamic stiffness data Cw, Kw, and the grinding wheel side dynamic stiffness data Ct, Kt.

However, in the present embodiment, the workpiece side dynamic stiffness data Cw, Kw include workpiece dynamic stiffness data Cwa, Kwa, support member dynamic stiffness data Cwb, Kwb, and contact dynamic stiffness data Cwc, Kwc. That is, the correction amount for the displacement is calculated from the grinding resistance Fn, the workpiece side dynamic stiffness data Cwa, Kwa, Cwb, Kwb, Cwc, Kwc, and the grinding wheel side dynamic stiffness data Ct, Kt.

The correction amount calculation unit 107 outputs the calculated correction amount to the estimation unit 102 . Based on the relative position between the workpiece W and the grinding wheel T, the shape of the outer peripheral surface of the workpiece W, and the shape of the outer peripheral surface of the grinding wheel T, which are acquired by the command value acquiring unit 101, as described above, the estimation unit 102 , to estimate the estimation target. However, due to the grinding force Fn, the relative position between the workpiece W and the grinding wheel T is different from the relative position determined by the command value.

Therefore, when estimating the estimation target, the estimation unit 102 uses the relative position calculated by the correction amount calculation unit 107 as the relative position between the workpiece W and the grinding wheel T in addition to the relative position acquired by the command value acquisition unit 101. A relative position to which a correction amount is added is used. That is, the estimation unit 102 estimates the estimation target based on the relative position based on the command value and the correction amount calculated using each dynamic stiffness data.

In particular, in the present embodiment, the correction amount calculator 107 outputs the calculated correction amount to the interference amount calculator 111 of the estimation unit 102 . As described above, the interference amount calculation unit 111 calculates the relative position between the workpiece W and the grinding wheel T acquired by the command value acquisition unit 101, the shape of the outer peripheral surface of the workpiece W, and the shape of the outer peripheral surface of the grinding wheel T. Based on this, the amount of interference between the workpiece W and the grinding wheel T is calculated. However, due to the grinding force Fn, the relative position between the workpiece W and the grinding wheel T is different from the relative position determined by the command value.

Therefore, the interference amount calculation unit 111 uses the relative position calculated by the correction amount calculation unit 107 in addition to the relative position acquired by the command value acquisition unit 101 as the relative position between the workpiece W and the grinding wheel T used to calculate the interference amount. The relative position to which the correction amount is added is used. That is, the interference amount calculator 111 calculates the interference amount based on the relative position based on the command value and the correction amount calculated using each dynamic stiffness data.

Since the interference amount calculation unit 111 calculates the interference amount considering the correction amount, the grinding efficiency calculation unit 112, the grinding characteristic determination unit 113, and the grinding resistance calculation unit 114 are calculated based on the interference amount considering the correction amount. Grinding efficiency Z', grinding characteristic kc, and grinding force Fn are obtained.

The output unit 108 outputs the estimation target estimated by the estimation unit 102 . That is, the output unit 108 outputs the state of the workpiece W or the grinding wheel T, the shape of the workpiece W, the shape of the grinding wheel T, and the mechanical state of the processing device 1 (the mechanical state of the grinder main body 2) during the grinding process. equivalent). The output unit 108 may, for example, teach the estimation result to a teaching device (not shown). The output unit 108 can also output the estimation result to the control device 3 a of the grinder body 2 . In this case, the control device 3a can correct the grinding conditions, for example, using the estimation result. That is, the control device 3a can control the grinding process using the estimation result.

The control device 3a can also use the estimation result to control the adjusting mechanism 42 of the tailstock device 40 to adjust the pressing force by the spindle center 34 and the tailstock center 41. Further, when the grinder main body 2 is equipped with a chuck, the control device 3a can also adjust the gripping force of the chuck using the estimation result. The control device 3a can also adjust the pressing force of the rest device 60 using the estimation result. Note that the control device 3a can appropriately select a controlled object using the estimation result.

In addition, the control device 3a uses the estimation results to perform the various processes described above. In addition, the control device 3a can also control processing using various dynamic stiffnesses determined by the dynamic stiffness determination unit 106 regardless of the estimation result. For example, the control device 3a adjusts the pressing force by the spindle center 34 and the tailstock center 41 and the gripping force of the chuck using various dynamic stiffnesses determined by the dynamic stiffness determination unit 106, regardless of the estimation results. , the pressing force of the rest device 60 can also be adjusted.

4. Effect According to the present embodiment, the control device 3a of the processing unit 3 uses the contact dynamic stiffness data Cwc, Kwc between the workpiece W and the workpiece support members (20, 30, 40, 60) to determine the desired perform the processing for the purpose of The desired target process is the process of controlling the machining, or the state of the workpiece W or the grinding wheel T during machining, the shape of the workpiece W, the shape of the grinding wheel T, and the mechanical status of the processing apparatus 1. This is a process of estimating at least one.

The contact dynamic stiffness data Cwc and Kwc are the values of the workpiece W and the workpiece support members (20, 30, 40, 60) exerted by the contact between the workpiece W and the workpiece support members (20, 30, 40, 60). is represented by a spring constant Kwc and a damping coefficient Cwc between By using the contact dynamic stiffness data Cwc, Kwc including the spring constant Kwc and the damping coefficient Cwc in this way, desired processing can be performed with high accuracy.

Further, as shown in FIGS. 7 and 8, the dynamic contact stiffness table includes adjustment elements relating to the support force of the workpiece support members (20, 30, 40, 60) and elements of the supported portion of the workpiece W. , and contact dynamic stiffness data Cwc, Kwc are stored in advance. Therefore, the workpiece-side dynamic stiffness determining unit 121 easily determines the contact dynamic stiffness data Cwc, Kwc using the adjustment elements and the elements of the supported portion at the time of processing and the correspondence stored in the contact dynamic stiffness table. can be determined to

In addition, as shown in FIG. 8, the contact dynamic stiffness table storage unit 103c additionally stores contact dynamic stiffness data obtained by performing interpolation processing. By generating the contact dynamic stiffness data Cwc, Kwc for conditions that have not been actually measured in this way, it becomes possible to estimate the estimation target with high accuracy and to control the control target.

In addition, the workpiece side dynamic stiffness data is separated into workpiece dynamic stiffness data Cwa, Kwa, support member dynamic stiffness data Cwb, Kwb, and contact dynamic stiffness data Cwc, Kwc. Separating each dynamic stiffness data in this way facilitates determination of each dynamic stiffness data. For example, even if the workpiece W and the workpiece support members (20, 30, 40, 60) are the same, only the contact dynamic stiffness data Cwc, Kwc will be Be changed. Therefore, arithmetic processing becomes easy. For example, when the estimation processing by the machining estimation device 3b and the control of the grinding processing by the control device 3a are performed at the same time, high-precision grinding processing can be realized by performing the arithmetic processing at high speed.

(Embodiment 2)
A processing apparatus 201 of this embodiment will be described with reference to FIG. The processing device 201 is intended for a processing device that performs cutting. The processing device 201 includes a lathe body 202 as a processing device body and a processing unit 203 .

The lathe body 202 turns the workpiece W by rotating the workpiece W and moving the cutting tool T2 relative to the workpiece W. The processing unit 203 includes a control device 203a that controls the lathe body 202, and a machining estimation device 203b that estimates an estimation target related to machining. The control device 203 a can control cutting by controlling the lathe body 202 . The machining estimating device 203b determines the state of the workpiece W or the cutting tool T2, the shape of the workpiece W, the shape of the cutting tool T2, and the mechanical state of the processing device 201 (the lathe body 202) during cutting by the lathe body 202. corresponding to the machine state). The machining estimating device 203b performs the estimation processing of the estimation target by inputting information used for cutting and performing a simulation.

The lathe body 202 includes, for example, a bed 210, a spindle device 220, a tailstock device 230, a rest device 240, and a tool table 250. The spindle device 220, the tailstock device 230, and the rest device 240 function as workpiece support members. The spindle device 220 is fixed to the upper surface of the bed 210, supports one end of the workpiece W, and drives the workpiece W to rotate. The spindle device 220 includes a spindle housing 221, a spindle 222, a spindle motor 223, a chuck 224, a spindle detector 225, and a spindle drive circuit (not shown).

The spindle housing 221 is fixed on the bed 210. The main shaft 222 is rotatably supported by the main shaft housing 221 via bearings. The spindle motor 223 drives the spindle 222 to rotate. A chuck 224 is fixed to the spindle 222 and grips one end of the workpiece W. As shown in FIG. The spindle detector 225 and the spindle drive circuit are provided to drive the spindle motor 223 .

The tailstock device 230 is arranged on the bed 210 so as to face the spindle device 220 in the Z-axis direction. The tailstock device 230 is provided on the bed 210 so as to be movable in the Z-axis direction. The tailstock device 230 includes a tailstock center 231 that supports the other end of the workpiece W. As shown in FIG.

The rest device 240 is fixed on the bed 210 and supports the outer peripheral surface of the workpiece W at the intermediate portion in the axial direction. In particular, the rest device 320 is arranged at a position that resists the cutting load that the workpiece W receives from the cutting tool T2.

The tool rest 250 includes a Z-axis slide table 251, an X-axis slide table 252, a turret (rotary tool rest) 253, and a plurality of cutting tools T2. The Z-axis slide table 251 is supported on the Z-axis guide surface 211 of the bed 210 so as to be movable in the Z-axis direction, and is moved in the Z-axis direction by the Z-axis drive mechanism 212 provided on the bed 210 .

The X-axis slide table 252 is supported by an X-axis guide surface 251a on a Z-axis slide table 251 so as to be movable in the X-axis direction. move to The turret 253 is rotatably provided on the X-axis slide table 252 about an axis parallel to the Z-axis direction. A plurality of cutting tools T2 are fixed to the outer peripheral surface of the turret 253 . The multiple cutting tools T2 can be different types of tools.

The control device 203a is a CNC (Computer Numerical Control) that executes machining control.
Control) device and PLC (Programmable Logic Controller) device. That is, the control device 203a controls the position of the cutting tool T2 by driving the Z-axis drive mechanism 212 and the X-axis drive mechanism 251b as moving devices based on the cutting program. That is, the control device 203a relatively moves the workpiece W and the cutting tool T2 by controlling the position of the cutting tool T2. Further, the control device 203a performs rotation control of the main shaft 222 and rotation control of the turret 253. FIG.

A modification estimation device 203b of this embodiment has the same configuration as the modification estimation device 3b of Embodiment 1 shown in FIG. However, the grinding in Embodiment 1 is changed to cutting, and the grinding wheel T is changed to a cutting tool T2.

Next, the workpiece-side dynamic stiffness (Cw, Kw) and the tool-side dynamic stiffness (Ct, Kt) in this embodiment will be described with reference to FIG. The workpiece-side dynamic rigidity (Cw, Kw) is the dynamic rigidity exerted when the workpiece W is supported by the spindle device 220, the tailstock device 230, and the rest device 240 as workpiece support members that constitute the lathe body 202. be. Workpiece side dynamic stiffness (Cw, Kw) is defined by damping coefficient Cw and spring constant Kw. The damping coefficient Cw is a value that represents the relationship between the relative speed of the workpiece W with respect to the reference positions of the spindle device 220, the tailstock device 230 and the rest device 240 and the external force that the workpiece W receives. The spring constant Kw is a value that represents the relationship between the relative position of the workpiece W with respect to the reference positions of the spindle device 220, the tailstock device 230 and the rest device 240 and the external force that the workpiece W receives.

As in the first embodiment, the workpiece side dynamic stiffness (Cw, Kw) is composed of workpiece dynamic stiffness (Cwa, Kwa), support member dynamic stiffness (Cwb, Kwb), workpiece W and workpiece support. contact dynamic stiffness (Cwc, Kwc) between members (20, 30, 40, 60).

The tool-side dynamic stiffness (Ct, Kt) is the dynamic stiffness related to the tool table 250 including the cutting tool T2. Tool-side dynamic stiffness (Ct, Kt) is defined by damping coefficient Ct and spring constant Kt. The damping coefficient Ct is a value that represents the relationship between the relative speed of the cutting tool T2 with respect to the reference position on the tool rest 250 and the external force that the cutting tool T2 receives. The spring constant Kt is a value that represents the relationship between the relative position of the cutting tool T2 with respect to the reference position on the tool rest 250 and the external force that the cutting tool T2 receives.

The processing device 201 in this embodiment has the same effects as the processing device 1 in the first embodiment.

(others)
In the above embodiment, the grinding process using the grinder main body 2 and the cutting process using the lathe main body 202 have been described as examples. In addition to these, cutting using a machining center is similarly applicable.

Claims

In a processing device (1, 201) for processing a workpiece (W) supported by workpiece support members (20, 30, 40, 60, 220, 230, 240) with tools (T, T2),
using contact dynamic stiffness data (Cwc, Kwc) between the workpiece and the workpiece support member exerted by the contact between the workpiece and the workpiece support member, or A processing device ( 1,201).
moreover,
Adjustment elements (34, 41, 60, 224, 231, 240) relating to the support force of the workpiece support member, elements (W, Wc, Wd) of the supported portion of the workpiece, and the contact dynamic stiffness data (Cwc, Kwc) and a contact dynamic stiffness table storage unit (103c) for pre-storing the corresponding relationship;
a dynamic stiffness determination unit (106) for determining the contact dynamic stiffness data using the adjustment elements and the supported part elements at the time of processing and the correspondence stored in the contact dynamic stiffness table storage unit; and,
with
The processing unit controls machining using the contact dynamic stiffness data determined by the dynamic stiffness determination unit, or controls the state of the workpiece or the tool during machining, the shape of the workpiece, the 2. The processing device according to claim 1, wherein at least one of a tool shape and a machine state of said processing device is estimated.
The contact dynamic stiffness table storage unit
A correspondence relationship between first conditions (A1, A2, A3, B1, B2, B3) regarding the adjustment elements and the elements of the supported portion and the contact dynamic stiffness data actually measured under the first conditions is stored in advance. and
Furthermore, by performing interpolation processing using the contact dynamic stiffness data for the first condition, the contact dynamic stiffness acquired for the second conditions (A1h, A2h, B1h, B2h) different from the first condition 3. The processing device according to claim 2, further storing data.
the element of the supported portion is a center hole (Wc, Wd) formed in the axial end face of the workpiece;
said workpiece support member comprises a support center (34, 41, 231) for axially pressing said workpiece against said center hole;
4. The processing apparatus according to claim 2, wherein said contact dynamic stiffness data is contact dynamic stiffness data between said center hole and said support center.
The support center is configured to be able to adjust the pressing force in the axial direction of the workpiece with respect to the workpiece,
The contact dynamic stiffness data is data that changes as the contact state between the center hole of the workpiece and the support center changes due to changes in the pressing force of the support center,
The processing unit uses the contact dynamic stiffness data to determine at least one of a state of the workpiece or the tool during machining, a shape of the workpiece, a shape of the tool, and a mechanical state of the processing device. 5. The processing apparatus according to claim 4, which estimates and adjusts the pressing force by said support center based on the estimation result.
the workpiece support member is a chuck (224) that grips the workpiece;
4. The processing apparatus according to any one of claims 1 to 3, wherein said contact dynamic stiffness data is contact dynamic stiffness data between said workpiece and said chuck.
The chuck is configured to be able to adjust a gripping force on the workpiece,
The contact dynamic stiffness data is data that changes as the contact state between the workpiece and the chuck changes due to changes in the gripping force of the chuck,
The processing unit uses the contact dynamic stiffness data to determine at least one of a state of the workpiece or the tool during machining, a shape of the workpiece, a shape of the tool, and a mechanical state of the processing device. 7. The processing apparatus according to claim 6, which estimates and adjusts said gripping force by said chuck based on the estimation result.
The workpiece support member is a rest device (60, 240) that supports the outer peripheral surface of the workpiece formed in a shaft shape,
The processing apparatus according to any one of claims 1 to 3, wherein said contact dynamic stiffness data is contact dynamic stiffness data between the outer peripheral surface of said workpiece and said rest device.
The rest device is configured to be able to adjust the pressing force against the outer peripheral surface of the workpiece,
The contact dynamic stiffness data is data that changes as the contact state between the outer peripheral surface of the workpiece and the rest device changes due to a change in the pressing force applied by the rest device,
The processing unit uses the contact dynamic stiffness data to determine at least one of a state of the workpiece or the tool during machining, a shape of the workpiece, a shape of the tool, and a mechanical state of the processing device. 9. The processing apparatus according to claim 8, which estimates and adjusts said pressing force by said rest device based on the estimation result.
The processing unit is
the contact dynamic stiffness data (Cwc, Kwc);
support member dynamic stiffness data (Cwb, Kwb), which is the dynamic stiffness of the workpiece support member; and
Using the workpiece dynamic stiffness data (Cwa, Kwa), which is the dynamic stiffness of the workpiece,
2. Controlling machining or estimating at least one of the state of the workpiece or the tool, the shape of the workpiece, the shape of the tool, and the mechanical state of the processing device during machining. 10. The processing apparatus according to any one of items 1 to 9.