JPH10315111A - Curved surface machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curved surface machining device which can remove roughness and unevenness in the high precision polishing of a free curved surface. SOLUTION: A work 7 is moved in x-, y-, z- axis direction by a three-axis direct-moving sliding part 2 to make the path of a cutting tool 8 agree with the curved surface 9 of the work 7 and a suitable depth of cut is given to a one-axis direct-moving sliding part 3 moving in z-axis direction to machine the surface of the work 7 into a curved surface. A tool pressing force by the cutting tool 8 is input to a personal computer 6a via a force sensor 5 and the personal computer 6a calculates the amount of several kinds of control based on the difference between a target tool pressing force and the measured tool pressing force and high pressure air is introduced into an air cylinder 10 with double cylinder chambers according to a control parameter based on the amount of control to control the tool pressing force by the cutting tool 8. This can remove the roughness and unevenness of the curved surface to produce the high precision curved surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a lens, for example,
The present invention relates to a curved surface processing apparatus for finishing a curved surface portion of a workpiece such as a mirror or a mold with ultra-precision, and in particular, to obtain a high-quality finished surface by removing minute waviness of the processed surface of the workpiece. To a curved surface processing apparatus capable of performing

[0002]

2. Description of the Related Art There are many known techniques relating to a curved surface processing apparatus for precisely processing and finishing a curved surface of a workpiece. For the mirror finishing of a curved mold, a method of using a processing tool having a low elastic coefficient, which is easily elastically deformed and easily adapts to a surface to be processed (polished surface), as a polisher has been put to practical use. In many cases, this polisher is usually used for polishing in combination with free abrasive grains such as diamond powder and silica.

[0003] As a known technique for performing finishing processing with high shape accuracy using these processing tools, Japanese Patent Application Laid-Open No. 61-26525 is known.
No. 7 discloses a “precision curved surface processing method”. As a mechanism for maintaining a constant pressure for keeping a tool pressing force of a working tool constant, a method disclosed in Japanese Patent Application Laid-Open No. 61-265657, a method disclosed in Japanese Patent Application Laid-Open Nos. 7-100751 and 8-197404, and the like are disclosed. Disclosures are given.

Further, in the above-mentioned known techniques, a spring or a weight is used as a pressing mechanism. However, in Japanese Patent Application Laid-Open Nos. 7-68456 and 7-241766, an air cylinder, a piezo element, and a ball screw feeder are disclosed. An active machining mechanism such as a mechanism is used. In addition, in the case of this pressurizing mechanism, a feedback control is performed to detect a pressing force applied from the processing tool to the work side and to make the pressing force constant.

[0005]

The above-mentioned prior arts each have a characteristic, and have a function of precisely finishing the surface without destroying the shape of the pre-processed surface.
For example, there is a problem that it is not possible to effectively remove the waviness of a roughness curve having a long cycle waviness as compared with a surface roughness curve of a wavelength of about 1 [mm]. Therefore, in the related art, a processing method of removing the waviness as much as possible by enlarging the tool contact area of the processing tool with the workpiece is merely adopted.

However, with this processing method, it has been difficult to remove the undulation of a curved surface having a mixture of a concave surface and a convex surface. That is, in the curved surface processing, it is necessary to correct both the roughness and the undulation of the curved surface for the precision curved surface finishing, but there is no technology that satisfies both of them in the conventional technology.

The present invention has been made in view of the above circumstances, and uses a processing tool whose shape has been adjusted so as to finish the surface roughness with high precision, and has a undulation having a period longer than the contact length of the processing tool. It is an object of the present invention to provide a curved surface processing apparatus capable of easily removing a surface and performing a highly accurate curved surface processing.

[0008]

In order to achieve the above object, a curved surface processing apparatus according to a first aspect is a processing apparatus for performing a curved surface processing while following a processing tool on a surface of a workpiece. The apparatus includes a three-axis linearly moving slide part for moving a workpiece in three orthogonal (X, Y, Z-axis) directions, and moving the processing tool parallel to one of the three axes. A one-axis linear slide unit to be held, a thrust generating mechanism for applying a thrust to the one-axis linear slide to apply a tool pressing force to the workpiece by the processing tool, and a thrust generating mechanism. A force sensor for detecting a tool pressing force applied to a workpiece, and a tool by the thrust generating mechanism unit based on a control parameter calculated based on a difference between the output value of the force sensor and a target tool pressing force, based on a difference between the force sensor and the target tool pressing force. A special feature is to provide a control mechanism for controlling the pressing force. To.

A curved surface processing apparatus according to a second aspect is characterized in that the thrust of the thrust generating mechanism is loaded by a double-chamber air cylinder.

According to a third aspect of the present invention, in the curved surface processing apparatus according to the second aspect, air pressure supplied from a high-pressure air source to each chamber of the double-chamber air cylinder is controlled by an electromagnetic valve. The resolution is 0.05 [kg
f / cm] or less.

According to a fourth aspect of the present invention, in the curved surface processing apparatus according to the first aspect, the control parameter is adjusted by an operator to a difference between the tool pressing force and the target tool pressing force at a certain time. It is characterized by being multiplied by a possible proportional coefficient.

According to a fifth aspect of the present invention, in the curved surface processing apparatus according to the first aspect, the control parameters are set such that the tool pressing force and the target tool pressing force at a certain time and a time range slightly before the time. And a product obtained by multiplying the integral value of the difference from the above by a proportional constant that can be adjusted by the operator.

According to a sixth aspect of the present invention, in the curved surface machining apparatus according to the first aspect, the control parameters are set such that the tool pressing force and the target tool pressing force at a certain time and a time slightly earlier than the time are set. , Which is obtained by multiplying the slope of the difference by a proportional constant that can be adjusted by the operator.

According to a seventh aspect of the present invention, in the curved surface processing apparatus according to the first aspect, the control parameter is adjusted by an operator to a difference between the tool pressing force and the target tool pressing force at a certain time. A control parameter multiplied by a possible proportional coefficient, and a control parameter obtained by multiplying an integral value of a difference between the tool pressing force and a target tool pressing force in a certain time period and a slightly earlier time range by a proportional constant adjustable by an operator. And a combination of at least two control parameters of control parameters obtained by multiplying the slope of the difference between the tool pressing force and the target tool pressing force at a certain time and slightly before that by a proportional constant adjustable by an operator. It is characterized by consisting of

According to an eighth aspect of the present invention, in the curved surface processing apparatus according to the first aspect, the processing tool comprises a processing portion and a shaft portion for holding the processing portion on a tool spindle. , The processed part is felt, nylon, cotton,
It is characterized by being made of silk fiber impregnated with polyurethane resin.

According to a ninth aspect of the present invention, there is provided the curved surface machining apparatus according to the eighth aspect, wherein a portion of the machining portion that contacts the workpiece is formed in an arc shape.

A curved surface processing apparatus according to a tenth aspect is the curved surface processing apparatus according to the first aspect, wherein the processed portion is made of an elastic whetstone mainly composed of polyvinyl acetal,
It is characterized in that the outermost layer is used in a semi-dissolved state by impregnating moisture from the surface layer.

According to a eleventh aspect of the present invention, in the curved surface machining apparatus according to the first aspect, the three-axis linearly moving slide portion has one of two axes other than the cutting direction axis. The present invention is characterized in that a tilting mechanism that can rotate around is provided.

According to a twelfth aspect of the present invention, in the curved surface machining apparatus according to the first aspect, the three-axis linearly moving slide portion is rotatable around two axes other than the cutting direction axis. It is characterized by adding a part.

For example, the workpiece is placed on a three-axis linear slide unit so as to move the workpiece along the curved surface of the processing surface of the workpiece, and the workpiece is moved by the one-axis linear slide unit. It is configured to be able to move along a direction parallel to one of the three axes. The thrust generating mechanism applies a tool pressing force to the processing tool to apply a thrust to the workpiece, detects the thrust by a force sensor, and calculates a difference between the tool pressing force and the target tool pressing force based on the detection signal. The thrust of the processing tool is automatically controlled by a control parameter obtained based on the difference, and the surface roughness and undulation of the workpiece are processed and finished to perform high-precision curved surface finishing. In addition, the material of the processing portion of the processing tool is devised, or one axis other than the three axes is formed as two axes so that a workpiece having a complicated curved surface is precisely machined.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a curved surface processing apparatus according to the present invention will be described in detail with reference to the drawings. First, a schematic configuration of an embodiment of a curved surface processing apparatus of the present invention will be described with reference to FIG. The curved surface processing apparatus 1 is roughly divided into a three-axis linearly moving slide portion 2 on which a workpiece 7 is placed, and a one-axis that holds a processing tool 8 and moves along one of the three axes. A linear slide unit 3, a thrust generating mechanism unit 4 for applying a thrust to the one-axis linear slide unit 3 to apply a tool pressing force to the workpiece 7, and a force sensor 5 for detecting the tool pressing force
And a control mechanism unit 6 that calculates control parameters with reference to the output value of the force sensor 5 and the target tool pressing force, and adjusts and controls the tool pressing force by the processing tool 8.

The three-axis linear slide 2 has a structure capable of linearly moving along the X, Y, and Z axes, and is controlled by a controller (not shown). The workpiece 7 is positioned and controlled by the three-axis linear slide unit 2 at a position corresponding to the shape of the curved surface 9 on the surface thereof. In this example, a three-axis linear slide unit 2
The force sensor 5 is mounted on the device, and the workpiece 7 is mounted on the force sensor 5.

In this embodiment, the one-axis linear slide unit 3 is configured to move along the Z-axis direction, and includes a main body mechanism 3a that holds the processing tool 8 and moves in the Z-axis direction. The processing tool 8 includes a processing portion 8a that comes into contact with the curved surface 9 of the workpiece 7 and a support shaft 8c for holding the processing portion 8a on a tool spindle 8b.

In this embodiment, the thrust generating mechanism 4 includes a double-chamber air cylinder 10, a first solenoid valve 11, and a second solenoid valve 12.
And a high-pressure air source 13 and the like. The double-chamber air cylinder 10 includes a forward drive chamber 10a and a reverse drive chamber 10b.
And a piston 14 separating the two chambers 10a and 10b.
Is connected to the one-axis linear slide unit 3. The resolution of the first and second solenoid valves 11 and 12 is 0.05 [kgf
/ Cm]. In the case where the curved surface 9 of the workpiece 7 and the processing tool 8 are in point contact with each other, the above-described resolution is necessary in order to realize the processing of a very small amount of 1 [μm] or less from the surface layer without breaking the curved surface shape. Become.

The force sensor 5 is a so-called load cell, and a personal computer 6a of the control mechanism 6 via a load cell amplifier 15.
Linked to Processing tool 8 detected by force sensor 5
Is detected in real time by the force sensor, and this detection signal is input to the personal computer 6 via the load cell amplifier 15 and stored. Control signals 1 and 2 for opening and closing the first and second solenoid valves 11 and 12 are sent from the personal computer 6. The control signal 1 is a PID control signal (proportional, integral, differential), and the control signal 2 is a constant control signal.

The computer 6a calculates control parameters to be described in detail later. When the tool pressing force of the processing tool 8 is different from the standard tool pressing force, the calculation by the personal computer 6 calculates the difference and obtains the control parameter by a predetermined control parameter calculation method. The control based on this control parameter is performed. Signals 1 and 2 are emitted. Thereby, the first and second solenoid valves 11, 1
2, the high-pressure air from the high-pressure air source 13 is sent to the forward drive chamber 10 and / or the reverse drive chamber 10b.

As a result, the one-axis linear slide unit 3 operates, and the tool pressing force by the processing tool 8 can be adjusted and controlled. By appropriately adjusting the method of the adjustment control using the control parameters, it is possible to perform highly accurate machining of the curved surface 9 having various shapes. In particular, in the curved surface processing apparatus 1 of the present invention, in addition to the three-axis linearly moving slide part 2,
, The movement in the Z-axis direction can be freely performed irrespective of the movement of the three-axis linear slide unit 2, and not only high-precision processing of the surface roughness but also undulation can be easily removed.

Next, how to obtain three types of control parameters will be described with reference to FIGS. FIG. 2 shows a control parameter consisting of the control value A. In the figure, the abscissa indicates the processing elapsed time T, the ordinate indicates the pressing force F, and the curve Fa indicates the change in the tool pressing force by the processing tool 8.
F ₀ indicates the target pressing force. In this example, F
₀ is a constant value, but is not limited to this.
The tool pressing force on the curve Fa at a given time T ₁ is P _1, and the difference (deviation) between P ₁ and F ₀ is D. The control value A consists of those hanging proportional coefficient K ₁ to the deviation D. Incidentally, the proportional factor K ₁ is a coefficient of an operator adjustable, corresponds to the adjustment factor discretion for obtaining the operator to allow the removal of the curved surface precision or undulation desired. The control using the control amount A is intended to improve responsiveness and responsiveness.

FIG. 3 shows a method of calculating a control parameter consisting of the control value B. The tool pressing force on the curve Fa at a position that goes back from the given time T ₁ by the specified time ΔT _{2 and} goes back by the time T ₁ and ΔT _{2 is set} to P ₁ and P _2, and these values and the target tool pressing are set. The area S within the time ΔT ₂ between the force F ₀ and the force F ₀ is obtained. Control amount B is determined from multiplied by the proportional coefficient K ₂ to the area S. In addition,
Proportional coefficient K ₂ is an adjustment factor of discretion of the operator as well as the proportionality factor K ₁ of the. The control amount B makes it easy to adjust the following operation of the processing tool 8 to follow the curved surface 9 with respect to the phase of the undulation.

FIG. 4 shows a method of calculating a control parameter consisting of the control value C. Time Δ specified from any time T ₁
T ₃ only back the data, the time at that time and T _0. The tool pressing forces at times T ₁ and T ₀ are P ₁ and P ₃ , and the inclination angle θ between the line P ₃ P ₁ connecting P ₃ and P ₂ and the line of the target tool pressing force F ₀ is obtained. This tan θ is obtained. The control amount C is obtained by multiplying the tan θ by a proportional coefficient K ₃ . It should be noted that the proportional coefficient K ₃ is calculated by using the above K ₁ , K ₂
Is an adjustment coefficient of the operator's discretion as in the case of The control amount C facilitates the adjustment of the following operation of the processing tool 8 to the curved surface 9 with respect to the undulation phase.

When the workpiece 7 is processed by the processing tool 8, the control amounts A, B, and C are calculated by the personal computer 6a. Control signals 1 and 2 are issued from the personal computer 6a to the first and second solenoid valves 11 and 12,
In the present invention, the control amounts A, B, and C can be independently issued as control command values, respectively.
And a control command value is issued to the first and second solenoid valves. In this case, how to adjust the values of the proportional constants K ₁ , K ₂ , and K ₃ is appropriately set according to the purpose of processing. That is, adjustment control is performed for the case where the purpose is to improve only the surface roughness while maintaining the shape of the pre-processed surface, or the case where the purpose is to remove the swell of a specific cycle while improving the surface roughness. Are different.

FIG. 5 is a schematic view showing a basic processing mode for improving the surface roughness, and FIG. 6 is a schematic view showing a processing mode for removing the waviness along with the improvement of the surface roughness. 6, a curve E indicates the curved surface 9 of the workpiece 7 and a curve F indicates the tool path of the processing tool 8. The operation of the processing tool 8 is controlled via the first and second solenoid valves 11 and 12 by adjusting the control amounts A, B and C so that the tool trajectory of the processing tool 8 is as shown in the figure. Thus, the processing tool 8 can be removed by strongly contacting the overlapping portion G shown in the drawing. Conversely, it is possible to control the processing tool 8 to make weak contact with the valley that does not overlap. That is, according to the present invention, a finished curved surface having a desired processing accuracy can be obtained by adjusting and controlling the control amounts A, B, and C according to the curved surface shape of the workpiece 7.

In FIG. 5, a spring 16 is shown in addition to the multi-chamber air cylinder 10 as a means for pressing the processing tool 8 of the thrust generating mechanism 4, but absorbs vibration during processing in the processing tool 8. This is also applicable to the case of FIG.

As described above, the processing tool 8 comprises the processing portion 8a and the shaft portion 8c which come into contact with the curved surface 9 of the workpiece 7, and the processing portion 8a has a large contact area which comes into contact with the curved surface 9; It is desirable that the material easily fits into a curved surface. For this reason,
The processed portion 8a is made of an elastic member, and its shape is an arc shape as an example. The foamed urethane resin has a drawback that the wettability with the processing liquid is low, the processing tool 8 easily floats on the water quality of the processing liquid, and the efficiency is hardly increased. Further, the felt has a high polishing efficiency, but has a drawback that the tool shape is significantly worn and deformed during processing and the shape of the curved surface 9 is easily broken. Therefore, in the present invention, for example, a material obtained by impregnating a fibrous material of felt, nylon, cotton, or silk with a polyurethane resin is used.

On the other hand, it is particularly desirable to use a grinding stone of fixed abrasive for high precision processing in the polishing processing. In the present invention, an elastic grindstone mainly composed of polyvinyl acetal is used as an example. In the case of using fixed abrasive grains, the number of rotations of the tool, the material properties of the distribution of abrasive grains on the tool,
It is excellent in ease of cleaning after processing, etc., and enables efficient and high-precision processing. Further, the elastic grindstone in the present invention is used by impregnating the surface layer thereof with water at the time of use to make the outermost layer semi-dissolved. In general, in the case of the conventional PVA grinding stone itself, for example, in the case of fine particles finer than # 3000 for mirror finishing, there is a problem that the particles are easily clogged, the sharpness is reduced, and scratches occur. In contrast,
The elastic whetstone of the present invention can obtain an abrasive holding force suitable for mirror polishing because the outermost layer is in a semi-molten state, generates an appropriate whetstone, and greatly reduces the occurrence of clogging and scratching. Can be done.

FIGS. 7A and 7B show another embodiment of the curved surface processing apparatus of the present invention. Although the control mechanism 6 and the three-axis linearly moving slide 2, the first and second solenoid valves 11, 12 and the like shown in FIG. 1 are not shown in the drawing, they are of course applicable. In addition, although the hanging tool 17 for holding the weight is provided on the uniaxial linear slide unit 3, the hanging tool 17 is naturally applied also in FIG. The curved surface processing apparatus 1a of this example is suitable for polishing a workpiece 7a having a cylindrical shape as shown in the figure, and has an inclined table 18 having a B-axis for rotating around a Y-axis. It is characterized by points. Note that due to the use of the tilt table 18,
The force sensor 5a is arranged at the position shown. The provision of the tilt table 18 having the B axis enables four-axis control. The B-axis is used to always keep the angle between the rotation axis of the processing tool 8 and the curved surface 9a of the workpiece 7 constant.
a, so that there is a merit that the tool pressing force can be accurately detected. This is particularly effective when deterioration in shape accuracy due to polishing is regarded as a problem.

FIGS. 8A and 8B show another embodiment of the curved surface processing apparatus of the present invention. This curved surface processing apparatus 1b is suitable for polishing a toric workpiece 7b having different radii of curvature in two orthogonal directions and a workpiece having a free-form surface. A structural feature is that a tilt table 19 having an A-axis for enabling rotation about the X-axis is employed. As the processing tool, a tire-shaped elastic processing tool 20 as shown is used. Note that the tilt table 19 having the A axis is
This is because the angle formed by the rotation axis of the elastic processing tool 20 and the YZ sectional curve of the workpiece 7b is always constant at the processing point. Thereby, the same peripheral speed portion on the elastic processing tool 20 can always be brought into contact with the curved surface 9b of the workpiece 7b, and there is an advantage that the tool pressing force against the curved surface 9b can be accurately detected. In addition, it is effective especially when deterioration of shape accuracy due to polishing is regarded as a problem.

[0038]

【The invention's effect】

1) According to the curved surface processing apparatus according to claim 1 of the present invention,
By providing the copying operation means and a means for generating a separate tool trajectory, it is possible to detect the undulation of the machined surface (curved surface) with respect to the target ideal shape by the force sensor, and to detect the tool pressing force. It is possible to adjust the response characteristic of the copying operation to a desired state by calculating and evaluating the waveform. For this reason, undulation of a curved surface can be removed in addition to finishing processing for improving the accuracy of curvature.

2) According to the curved surface processing apparatus according to the second aspect of the present invention, the use of a multi-chamber air cylinder makes it possible to avoid the impact pressure and to reduce the response speed due to the mechanical friction of the cylinder. Can cover lowness.

3) According to the curved surface processing apparatus according to the third aspect of the present invention, the air pressure in each chamber of the multi-chamber cylinder can be controlled independently, so that the responsiveness and the degree of freedom are improved. Can be achieved. In addition, by setting the resolution to 0.05 [kgf / cm] or less, the shape of the curved surface can be reduced by 1
[Μm] Fine polishing with a thickness of not more than [μm] is possible.

4) According to the curved surface processing apparatus of the fourth aspect of the present invention, the responsiveness and responsiveness of pressurization can be easily adjusted by using the control parameters.

5) According to the curved surface processing apparatus according to claim 5 of the present invention, by using this control parameter,
Adjustment for delaying the follow-up operation of the processing tool to the workpiece with respect to the undulation phase can be easily performed.

6) According to the curved surface processing apparatus according to the sixth aspect of the present invention, by using the control parameters, it is possible to easily adjust the following operation of the processing tool to the processing surface with respect to the phase of the undulation. .

7) According to the curved surface processing apparatus according to the seventh aspect of the present invention, since the control parameters of the fourth, fifth, and sixth aspects are used in combination, the degree of freedom of the following operation of the processing tool to the processed surface is achieved. And undulation can be efficiently removed in actual processing in which undulations of different periods are mixed.

8) According to the curved surface processing apparatus according to the eighth aspect of the present invention, the processed part of the processing tool is made of a material such as a felt impregnated with a polyurethane resin, so that the curved surface shape is not broken. Effective processing can be performed, and the life of the processing tool can be improved.

9) According to the curved surface processing apparatus of the ninth aspect of the present invention, by forming the portion of the processing portion in contact with the curved surface of the processing tool in an arc shape, the contact area with the workpiece can be improved. The adaptability can be improved, and high-precision processing can be performed.

10) According to the curved surface processing apparatus of the tenth aspect of the present invention, high-efficiency and high-precision processing can be performed by using the elastic grindstone of the present invention, and the occurrence of clogging and scratches is greatly reduced. Can be reduced.

According to the eleventh aspect of the present invention, a high-precision machining of a cylinder-shaped machining surface becomes possible.

12) According to the curved surface processing apparatus of the twelfth aspect of the present invention, high precision processing of a toroidal surface or a free-form surface can be performed.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a curved surface processing apparatus of the present invention.

FIG. 2 is a time and tool pressing force diagram for explaining a method of calculating a control amount A;

FIG. 3 is a time and tool pressing force diagram for explaining a method of calculating a control amount B;

FIG. 4 is a time and tool pressing force diagram for explaining a method of calculating a control amount C;

FIG. 5 is a schematic view showing processing along the curvature roughness by the curved surface processing apparatus of the present invention.

FIG. 6 is a schematic diagram for explaining a processing method for removing waviness by the curved surface processing apparatus of the present invention.

FIG. 7 is a partial configuration diagram showing another embodiment of the curved surface processing apparatus of the present invention.

FIG. 8 is a partial configuration diagram showing still another embodiment of the curved surface processing apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Curved surface processing device 1a Curved surface processing device 1b Curved surface processing device 2 3-axis linear slide unit 3 1-axis linear slide unit 3a Main body mechanism unit 4 Thrust generation mechanism unit 5 Force sensor 5a Force sensor 6 Control mechanism unit 6a Personal computer 7 Object 7a Workpiece 7b Workpiece 8 Working tool 8a Working part 8b Tool spindle 8c Shaft part 9 Curved surface 9a Curved surface 9b Curved surface 10 Double chamber air cylinder 10a Forward drive chamber 10b Retreat drive chamber 11 First electromagnetic valve 12 Second Solenoid valve 13 high-pressure air source 14 piston 15 load cell amplifier 16 spring 17 hanging tool 18 tilt table 19 tilt table 20 elastic processing tool

Claims (12)

[Claims] 1. A processing apparatus for performing a curved surface processing while following a processing tool on a surface of a workpiece, the apparatus comprising:
A three-axis linearly-moving slide part for moving the workpiece in the direction of the axis (X, Y, Z-axis), and a one-axis linearly-movable slide part for moving parallel to one of the three axes and holding the processing tool A thrust generating mechanism for applying a thrust to the single-axis linear slide portion to apply a tool pressing force to the workpiece by the processing tool; and a tool pressing applied to the workpiece by the thrust generating mechanism. A force sensor for detecting a force, and a control mechanism for controlling a tool pressing force by the thrust generating mechanism with a control parameter calculated based on a difference between the output value of the force sensor and a target tool pressing force. And a curved surface processing apparatus characterized in that: 2. The curved surface processing apparatus according to claim 1, wherein the thrust of the thrust generating mechanism is applied by a double-chamber air cylinder. 3. The air pressure supplied from a high-pressure air source to each chamber of the double-chamber air cylinder is controlled by a solenoid valve, and the resolution is adjusted to a sensitivity of 0.05 [kgf / cm] or less. The curved surface processing apparatus according to claim 2, wherein 4. The control parameter according to claim 1, wherein the control parameter is obtained by multiplying a difference between the tool pressing force at a certain time and the target tool pressing force by a proportional coefficient adjustable by an operator. Curved surface processing equipment. 5. The control parameter is obtained by multiplying an integral value of a difference between the tool pressing force and a target tool pressing force in a certain time period and a slightly earlier time range by a proportional constant adjustable by an operator. The curved surface processing apparatus according to claim 1, wherein: 6. The method according to claim 6, wherein the control parameter is obtained by multiplying a slope of a difference between the tool pressing force and a target tool pressing force at a certain time and a time slightly earlier by a constant constant adjustable by an operator. The curved surface processing apparatus according to claim 1, wherein: 7. The control parameter includes a control parameter obtained by multiplying a difference between the tool pressing force and the target tool pressing force at a certain time by a proportional coefficient adjustable by an operator, a certain time and a time slightly earlier than the control parameter. A control parameter obtained by multiplying an integral value of a difference between the tool pressing force and the target tool pressing force in a range by a proportional constant adjustable by an operator, and the tool pressing force and the target tool pressing at a certain time and a time slightly earlier than the control parameter. The curved surface processing apparatus according to claim 1, comprising a combination of at least two control parameters among control parameters obtained by multiplying a slope of a difference from a force by a proportional constant adjustable by an operator. 8. The processing tool comprises a processing portion and a shaft portion for holding the processing portion on a tool spindle, and the processing portion is formed by applying a polyurethane resin to felt, nylon, cotton, or silk fibers. The curved surface processing apparatus according to claim 1, wherein the apparatus is formed by impregnation. 9. The curved surface processing apparatus according to claim 8, wherein a portion of the processing portion that contacts the workpiece is formed in an arc shape. 10. The processing part according to claim 1, wherein the processing part is made of an elastic grindstone containing polyvinyl acetal as a main component, and the outermost layer is used in a semi-dissolved state by impregnating moisture from the surface layer. Curved surface processing equipment. 11. The three-axis linearly-moving slide portion is provided with a tilt mechanism portion rotatable around any one of two axes other than the cutting direction axis. The curved surface processing apparatus according to claim 1. 12. The curved surface processing apparatus according to claim 1, wherein the three-axis linearly moving slide part is provided with a tilting mechanism part rotatable around two axes other than the cutting direction axis.