JPH03142159A - Push pressure control type grinding device - Google Patents

Abstract

PURPOSE:To perform a grinding work with a constant push pressure irrespective of the size of a residual grinding quantity by composing it so as to find a virtual spring constant from the grinding deviation so that a desired push pressure is obtainable even in case of the residual grinding quantity becoming less with equipping a push pressure setting part and spring constant arithmetic setting part. CONSTITUTION:A push preassure setting means 32 for setting a push pressure necessary for grinding work and a grinding deviation calculating means 36 finding the grinding deviation on each optional gap in the moving direction of a grinding tool 7 based on the finishing position of a work and the positional data of the grinding tool 7 output from a position detecting means 34 are provided. Then, a virtual spring constant is calculated by an arithmetic part 33 so that the push pressure becomes the set value set on the push pressure setting means 32, based on the output value of the push pressure setting means 32 and that of a grinding deviation calculating means 36 and this virtual spring constant is set by a spring constant arithmetic setting means 40 on a control means 26.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pressure-controlled grinding device, and particularly to a grinding device in which position and force are controlled, in which the pressure of the grinding tool is always set. The present invention relates to a pressure-controlled grinding device that is controlled to a desired value.

[Conventional technology]

Conventionally, for industrial robots, a virtual compliance control method has been proposed that allows a multi-degree-of-freedom working machine to perform a predetermined task by controlling its position and force (Japanese Patent Application Laid-Open No. 1983-1999).
35915, etc.).

Generally, in a working machine equipped with this control system, a force sensor is disposed on the wrist of the arm, and a working tool is attached via this force sensor. Then, control parameters such as virtual mass, spring constant, viscous damping coefficient, etc. that determine the motion characteristics of the tool are set in the control device, and these set values, reference position and orientation commands supplied from the outside, and force information applied to the tool are set. A speed command value for the tool is calculated based on information on the actual position and orientation of the tool, and this command value is supplied from the control device to the tool drive device via the drive circuit.

As a result, the tool moves to follow the shape of the workpiece and performs the grinding operation. Virtual compliance control calculates the spring force according to the deviation between the position where the tool should move specified by the control device and the actual position of the tool, and the virtual spring constant set as a control parameter. However, this spring force is used as force when pressing the tool against the workpiece, and a target force command value is given to the tool. The above-mentioned control system realized by software can give a tool for grinding a motion characteristic as if it were equipped with a real mechanical spring mechanism.

[Problem to be solved by the invention]

With a grinding device that operates according to conventional virtual compliance control, by controlling the position and force, it is possible to perform grinding while pressing the tool against the workpiece to some extent. However, with the control method of conventional equipment, problems such as leaving uncut parts at the finished position of the workpiece occur, and sufficient consideration has been given to adjusting the force to press the tool according to the amount to be removed. It wasn't. More specifically, for example, if the spring constant in the direction of applying pressure to the tool is a fixed value, the spring constant may be set virtually as the grinding work progresses and the amount of uncut material decreases. Since the spring element is in a substantially stretched state, the pressing force of the tool is reduced, so that the workpiece surface cannot be sufficiently ground, resulting in uncut parts. In addition, in a grinding device equipped with a control system that can change the spring constant in the pressing direction, if the spring constant in the pressing direction is set to a large value and a large amount is removed from the work surface, the grinding device If an overload condition occurs, and on the other hand, if the spring constant in the pressing direction is set to a small value and the amount of scraping on the work surface is also small, then an underload condition will occur.

An object of the present invention is to provide a grinding device that is equipped with a feedback loop of position and force and performs grinding work under the control of position and force, while maintaining the pressing force of a grinding tool at a desired value. It is an object of the present invention to provide a pressing force control type grinding device that can be accurately controlled, grind a part to be ground with good precision, and form an accurate finished surface.

The position and force control system employed in the pressure-controlled grinding device according to the present invention can be applied to other multi-degree-of-freedom working machines having similar functions.

[Means to solve the problem]

The pressing force control type grinding device according to the present invention includes a force detection means for detecting the force of at least one axis applied to the grinding tool, a position detection means for detecting the position of the grinding tool, and each of the force detection means and the position detection means. control means for controlling the position and force of the grinding tool using the force and position data detected by the grinding tool;
In a grinding device that determines the pressing force of a grinding tool against a workpiece using a virtual spring constant set by a control means, there is provided a pressing foot means for setting the pressing force required for grinding work, and a finishing position of the workpiece. Grinding deviation calculation means for calculating a grinding deviation at each arbitrary interval in the moving direction of the grinding tool based on the position data of the grinding tool outputted by the position detection means;
Based on the output value of the pressing force setting means and the output value of the grinding deviation calculating means, a virtual spring constant is calculated so that the pressing force becomes the set value set in the pressing force setting means, and this virtual spring constant is used as the control means. and a spring constant calculation setting means.

The pressing force control type grinding device according to the present invention takes in the grinding deviation calculated by the grinding deviation calculation means, compares the calculated grinding deviation with a preset deviation reference value, and continues the grinding operation. The present invention is characterized in that it has a determining means for determining whether the process is completed or terminated.

The pressing force control type grinding device according to the present invention is characterized in that it has a determining means for determining whether to continue or end the grinding work based on the force information output by the force detecting means.

Further, in the pressing force control type grinding device according to the present invention, in each of the above configurations, the grinding deviation calculation means includes an averaging processing means, and the averaging processing means calculates the grinding deviation at arbitrary intervals for a specific grinding work section. The average value of the plurality of grinding deviations obtained is calculated, and the grinding deviation of this average value is used as the output value of the grinding deviation calculation means.

[Effect]

In the pressing force control type grinding device according to the present invention, the amount of uncut material on the part to be ground is determined by the grinding deviation calculation means, the virtual spring constant is determined according to the amount, and the new virtual spring constant value thus determined is set in the control means. By doing so, even if the amount of uncut portion of the part to be ground changes, the pressing force of the grinding tool against the workpiece is adjusted to a desired constant pressing force.

Further, the pressing force control type grinding device according to the present invention is provided with a determination means for determining whether or not to continue the grinding operation by comparing the grinding deviation with the deviation reference value or by force information output from the force detection means. , the grinding work can be automated, and the efficiency and finishing accuracy of the grinding work can be improved.

In the pressing force control type grinding device according to the present invention, a virtual spring constant is determined using the average value of the grinding deviation obtained by the averaging processing means, and a stable value that generates the desired pressing force is determined for a specific grinding work section. A virtual spring constant can be obtained.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the overall configuration of a pressing force control type grinding device according to the present invention. In FIG. 1, 1 is a grinding device main body, an arm 2 having a plurality of joints is attached to a support base 3,
Due to the movement of each joint of the arm 2, the tip of the arm moves to a position required for work, and the posture of the entire arm changes to the position required for work. A 6-axis force sensor 5 is attached to the wrist part 4 located at the tip of the arm 2, and a grinding tool 7, which is a hand effector that performs grinding work on the workpiece 6, is attached to the tip of the force sensor 5. It is being Reference numeral 8 denotes a controller, and this controller 8 has a built-in control means composed of a computer, etc., and uses predetermined calculation formulas for controlling the position and force and according to a predetermined procedure to control the grinding device main body. It has the function of performing position/force control on the The controller 8 gives a command signal for instructing the operation of the grinding work to the grinding device main body through a signal line 9, obtains operation information of the motor etc. from the grinding device main body 1, and also receives information from the force sensor 5 to the grinding tool 7. They are electrically connected to each other so as to receive detection signals, ie force signals 10, regarding applied forces and moments. Reference numeral 11 denotes an operating device that is carried by the operator and operated as needed, and is provided with a numeric keypad and a plurality of operating switches that can give various commands to the controller 8. By operating various operation switches of the operating device 11, the operator can, for example, teach the working operation, set the working conditions, and furthermore, as described later, set the pressing force of the grinding tool 7, and set the reference value of the grinding deviation with respect to the finishing position. settings, etc.

Next, a specific configuration of the control mechanism according to the present invention realized by the controller 8 will be explained based on the block diagram of FIG. 2. The control method of the present invention applied to the grinding device main body l is realized by software or other hardware circuits using a computer included in the controller 8, and FIG. 2 shows a diagram of the control elements. A block diagram is shown to make the configuration clear.

In FIG. 2, a plurality of drive motors (not shown) for moving each joint of the arm 2 are built into the grinding device main body 1. An angle meter 21 for measuring the amount of drive is attached to these drive motors, and the axis angle data of each joint can be obtained by this angle meter 21.

First, the configuration of the position/force control calculation system will be explained.

The force and moment signals output from the force sensor 5 placed at the tip of the arm are sent to the force acting nose 22, and the force acting nose 22 transforms the sensor coordinate system into the reference coordinate system (absolute coordinate system). The force t at the point of contact between the workpiece and the grinding tool 7 is calculated by converting and performing gravity compensation by subtracting the gravitational force of the grinding tool 7. Further, the angle data of each axis detected by the angle meter 21 mentioned above is sent to the position calculation section 23, and the position and orientation X of the grinding tool 7 in the absolute coordinate system are calculated by the position calculation section 23 from these angle data. be done. Then, this position and attitude
The positional deviation ΔX is determined. Note that the method of setting the positional target value in the positional target value setting section 24 will be explained in detail later. As described above, the force performance obtained by the force acting nose section 22 and the position deviation ΔX regarding the position and posture obtained by the position deviation calculation section 25 are respectively input to the position/force control calculation section 26.

The position/force control calculation section 26 includes a subtracter 27, a spring constant calculation section 28, and a characteristic compensation calculation section 29. The output f of the force acting nose section 22 is given to a subtracter 27, and the positional deviation ΔX obtained by the positional deviation computing section 25 is input to a spring constant computing section 28.

In the spring constant calculating section 28, a virtual spring constant matrix K is set. The spring constant calculation unit 28 calculates the input positional deviation Δ
ΔX is calculated by multiplying the virtual spring constant matrix set to X by 2. In this embodiment, the values of each axis in the spring constant matrix are not fixed values, but are changed to appropriate values as necessary. The virtual spring constant in the direction in which the grinding tool 7 is pressed against the workpiece 6 is calculated by the spring constant calculation and setting section 30 as described later.

ΔX is applied to the output of the spring constant calculating section 28 to a subtracter 27 . The subtracter 27 calculates ΔX to f−, and the calculation result of the subtracter 27 is given to the characteristic compensation calculation unit 29. A controller gain Kc is set in the characteristic compensation calculation section 29, and ΔX is applied to the input f- by this Kc.
is subjected to control characteristic compensation, and the characteristic compensation calculation section 29 calculates the speed command value M.

The speed command value V thus obtained by the position/force control calculation section 26 is supplied to the drive command section 31, and the speed command value V is converted into a drive command for each drive motor of the grinding device main body 1 by this drive command section 31. Converted to value 0.

The converted drive command value 0 is supplied to each drive motor of the grinding device main body t, and the motors operate according to this command value.

Next, the spring constant calculation setting section 30 having the function of changing the spring constant value in the pressing direction in the spring constant matrix of the spring constant calculation section 28 will be explained. Spring constant calculation setting section 30
is a control system circuit portion that sequentially calculates, changes, and sets the virtual spring constant in the pressing direction by the grinding tool, which is set by the spring constant calculation unit 28. Below, the configuration of the spring constant calculation setting section 30 and how to calculate a virtual spring constant using that configuration will be explained.

In the spring constant calculation setting unit 30, when the grinding apparatus main body 1 applies pressing force to the workpiece 6 with the grinding tool 7, a virtual spring constant in the direction of the pressing force is calculated between the grinding finishing position of the workpiece 6 and the workpiece currently being processed. It is characterized in that it is configured to be changed in accordance with the difference (distance) from the grinding position of No. 6, in other words, the amount of uncut material with respect to the finishing position.

Reference numeral 32 denotes a pressing window portion, and a desired pressing force Fg+ is set in this pressing window portion 32 by the operator operating the operating device 11. This desired pressing force Fgr means that the grinding tool 7 is
The pressing force that allows the maximum performance to be exerted is the force, or the optimum pressing determined based on the material of the workpiece 6, etc. means the force. This pressing force Fg+ is maintained at a constant value during the grinding operation.

The pressing force Fgr set on the pressing window section 32 is applied to the spring constant calculation section 33.

On the other hand, during the grinding work, the data regarding the position of the grinding tool 7 obtained by the position calculation unit 23 is transmitted to the position extraction unit 3.
4, the data are extracted at arbitrary intervals, for example, at predetermined distance intervals. The position data of the grinding tool 7 extracted by the position extraction section 34 is supplied to the finishing position calculation section 35 and the grinding deviation calculation section 36. The finishing position calculation unit 35 calculates the finishing position of the workpiece 6 based on the position data of the grinding tool extracted by the position extraction unit 34. As for this finishing position, the finishing position set at the start of the work may be used.

Alternatively, a new finishing position may be calculated by using the finishing position that has already been set and then applying interpolation calculation. Then, the grinding deviation calculation unit 36 calculates the direction in which pressing force is being applied based on the current grinding position of the grinding tool 7 extracted by the position extraction unit 34 and the finishing position obtained by the finishing position calculation unit 35. The grinding deviation is calculated and sent to the storage section 37 at the next stage, where it is stored. The above grinding deviation is △hi (i=
1.2.3...). This grinding deviation is determined for each arbitrary distance interval.

38 is an averaging processing section, and this averaging processing section 38 is
After a series of grinding operations are completed, for example, after one grinding operation is completed for a designated grinding section, all the grinding deviations in the section are calculated for each arbitrary distance interval and stored in the storage unit 37. The average value Δh is determined based on the value of Δhi. In this case, the well-known arithmetic mean is used, for example, to determine the average value. The average value Δh of the grinding deviation in a specific grinding section calculated by the averaging processing section 38 in this way is calculated by the spring constant calculation section 33.
and is given to the end determination section 39, which will be described later.

The spring constant calculation unit 33 uses the desired pressing force 6Fgr and the average value Δh to move the grinding tool 7 to the workpiece 6.
A spring constant Kn is calculated so that a desired pressing force Fg+ is applied to the spring. The calculation formula is as follows.

K n = F H /Δh The spring constant Kn thus obtained is set in the virtual spring constant setting section 40, and the set value is further given to the spring constant calculation section 28 of the position/force control calculation section 26. As a result, the spring constant value in the pressing direction in the virtual spring constant matrix of the spring constant calculation unit 28 is changed. In this way, each time the grinding operation for a predetermined section is completed, the spring constant in the pressing direction is set for the grinding operation for a new predetermined section.

Next, the end determination section 39 will be explained. End determination section 39
has a function of determining whether the grinding work should be continued or terminated, and is composed of a comparison and determination section 41 and a deviation reference value setting section 42 that provides a deviation reference value H to this comparison and determination section 41. The comparison judgment unit 41 receives the average value Δh of the grinding deviation from the averaging processing unit 38 and the deviation reference value H from the deviation reference value setting unit 42.
is input and these two values are compared. Then, when Δh≦H, the comparison/determination unit 41 outputs a command to end the grinding work, and on the other hand, when Δh>H, it outputs a command to continue the grinding work.

The command to end the grinding and the command to continue the grinding work are sent to the next-stage grinding processing calculation section 43. The above deviation reference value setting section 4
The deviation reference value H set in step 2 is, for example, a value such as a finishing tolerance.

Next, when the grinding processing calculation unit 43 receives a command to end the grinding work from the comparison judgment unit 41, it executes a control procedure to end the grinding work, and on the other hand, when it receives a command to continue the grinding work, it starts the next series of grinding operations. The positional target value of the work route for is calculated, and this positional target value is given to the positional target value setting section 24 and set there.

FIG. 3 shows an example of the grinding operation of the grinding device main body 1 based on the pressing force control system having the above configuration and operation. In Fig. 3, 2 is an arm, 5 is a force sensor, 7 is a grinding tool,
6 is a workpiece. 50 is a portion to be ground remaining on the surface of the workpiece 6, and the grinding tool 7 performs the work of grinding the portion to be ground 50 to a finishing position C. The grinding section by the grinding tool 7 is a linear section between the taught points A and B, and for the grinding tool 7, the 2-axis direction in FIG. 3 (vertical direction in the figure) is the pressing direction, and the X-axis direction is the direction of movement.

Further, the surface C of the workpiece 6 is the finishing position, and a deviation reference value H for finishing the grinding work is set above the surface C. This deviation reference value H is determined by the deviation reference value setting section 4.
It is set to 2. In this state, the grinding tool 7
grinds the part to be ground 50 from point A to point B, and when the grinding is finished, returns to point A and repeats the same grinding operation. In one grinding operation moving from point A to point B, the distance between AB is divided finely by Δl. This distance Δl is the above-described arbitrary interval for the position extraction unit 34 to extract the position of the grinding tool 7 at an appropriate interval.

The state shown in FIG. 3 shows a state 9 in which the grinding tool 7 is moving from point A to point B while performing a grinding operation. The spring constant in the pressing direction in this grinding operation is set to the value obtained in the immediately preceding grinding operation. In this grinding work, while performing the grinding operation,
Grinding deviation Δhi for each arbitrary distance interval Δl from teaching point A
seek. This Δh i is determined by the position extraction section 34, finishing position calculation section 35, and grinding deviation calculation section 36.

The obtained grinding deviation Δhi is stored in the storage unit 37, respectively. All the grinding deviations Δhi calculated between point A and point B are stored in the storage unit 37. When the grinding work from teaching point A to teaching point B is completed, the storage unit 3
A plurality of grinding deviations Δhi (i=1.2
．． 3...), the averaging processing unit 38 calculates their average value Δh. Using this average value Δh, the spring constant calculation unit 33 calculates the pressure direction (
Calculate the virtual spring constant Kn required when applying the pressing force Fg' in the Z-axis direction).The calculated virtual spring constant K
n is given to the virtual spring constant setting section 40, and further, the spring constant in the pressing direction in the spring constant matrix of the spring constant calculation section 208 is changed according to the set value. On the other hand, the average value Δh of the grinding deviation is determined by the end determination unit 39
The comparison and determination section 41 compares it with the deviation reference value H, and as described above, it is determined whether or not to perform the next grinding operation. When the grinding operation continues, a predetermined positional target value is determined by the grinding processing calculation section 43, and this target value is set in the positional target value setting section 24. Based on this action, the grinding tool 7 returns to the position of the teaching point A again by the normal function of the position/force control calculation unit 26, and the desired pressing force Fgr is applied toward the teaching point B by the newly set spring constant Kn. The grinding work is started while adding the workpiece 6 to the workpiece 6. In this grinding work, similarly to the above, the spring constant calculation setting section 30 and the end determination section 39 calculate the average value of the grinding deviation, calculate a new virtual spring constant in the pressing direction based on this average value, and perform the grinding work. A determination is made as to whether or not to terminate. In this way, the part to be ground 5 is repeatedly
0 is ground. Note that the movement of the grinding tool 7 for the grinding work may be such that it is moved back and forth between teaching points A and B.

Next, a second embodiment of the present invention will be described based on FIG.

FIG. 4 shows the main structure of the second embodiment.

In this embodiment, the average value Δh of the grinding deviation is not calculated, but the virtual spring constant is calculated in the spring constant calculation unit 33 each time based on the grinding deviation Δht calculated by the grinding deviation calculation unit 36 at arbitrary intervals. configured to calculate. Therefore, in this embodiment, the averaging processing section 38 is omitted, and the value of the grinding deviation Δhi obtained by the grinding deviation calculation section 36 is directly given to the spring constant calculation section 33 and the storage section 37. The subsequent control processing subsequent to the spring constant calculating section 33 is the same as in the first embodiment. For each grinding deviation Δhj stored in the storage unit 37, after a series of grinding operations is completed, a comparison and determination unit 41 determines whether or not all Δhi (i=1.2°3, . . . ) have been completed. At that time, if even one H in the grinding path satisfies the condition of Δhi,
It is determined that the grinding work should be continued. The subsequent control processing is the same as in the first embodiment.

According to the configuration of this embodiment, the grinding deviation is measured at every arbitrary distance interval Δl, and thereby the virtual spring constant in the pressing direction can be changed and set finely at short distance intervals. Therefore, in this embodiment, the finished surface of the workpiece 6 is an irregular surface, and the desired pressing force set in the pressing window part 32 is uniformly applied to the workpiece whose grinding deviation changes irregularly. It has the advantage that it can be added to

Next, a third embodiment of the present invention will be described based on FIG.

FIG. 5 shows the main structure of the third embodiment.

In this embodiment, the determination of whether to finish or continue the grinding operation is not made based on the value of the grinding deviation, but is made based on the force information obtained from the force acting nose section 22. In the grinding operation, a reaction force obtained from the workpiece 6 that opposes the pressing force applied to the workpiece 6 from the grinding tool 7 is detected by the force sensor 5, and converted into an absolute coordinate system by the force acting nose 22. In this case, when the grinding tool 7 reaches the finishing position, the amount to be ground becomes 0, and no reaction force is generated from the workpiece 6 to the grinding tool 7. Therefore, by monitoring the force detected by the force sensor 5, it is possible to determine whether the grinding tool 7 has reached the finishing position. Therefore, the powerful nose part 2
A force extraction unit 60 is provided which inputs the force actuality outputted by the force sensor 2, and this force extraction unit 60 extracts the force actuality i in the pressing direction detected by the force sensor 5 at arbitrary intervals, and this force ti is sent to the force determination unit. 61.

The force determination unit 61 compares fi with the reaction force value O when the amount of grinding given from the force reference value setting unit 62 is O, and if fi is a value exceeding 0, it is determined that there is uncut material, and the grinding is performed. A signal is sent to the processing calculation unit 43 to repeat the grinding operation and continue the grinding operation. fi
When is smaller than 0, a signal to end the grinding operation is sent to the grinding processing calculation section 43. The other configurations and operations are the same as the embodiment shown in FIG. 2, except for the position-based end determination section 39. In addition, the reaction force value set by the force reference value setting section 62 can also be a value of reaction force generated within the finishing intersection of the workpiece, for example.

In the above embodiment, an example was explained in which the pressing force control method according to the present invention is applied to a grinding device. Of course, the changing control method can be applied to other multi-degree-of-freedom working machines similar to grinding machines.

〔Effect of the invention〕

As is clear from the above description, the present invention provides the following effects.

A grinding device with a position/force control section is equipped with a pressing window section and a spring constant calculation setting section, and the virtual spring constant is calculated from the grinding deviation so that the desired pressing force can be obtained even when the remaining amount of grinding is small. Since it is configured to obtain the amount of grinding remaining, the grinding work can be performed with a constant pressing force regardless of the amount of remaining grinding.

In addition, as the grinding work progresses and the remaining amount of grinding decreases, the virtual spring constant increases, so it is possible to finally obtain the same rigidity as position control, increasing the efficiency and finishing accuracy of the grinding work.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a grinding device to which the present invention is applied, FIG. 2 is a block configuration diagram showing a specific configuration of a pressing force control device, FIG. FIG. 4 is a block diagram of main parts showing another modified example of the pressing force control device, and FIG. 5 is a block diagram of main parts showing another modified example of the pressing force control device. [Explanation of symbols] 1... Grinding device main body 2... Arm 5... Force sensor 6... Work 7... Grinding tool 8 ......Controller 11...Manufacturer 22...Force acting nose section 23...Position calculation section 24...Position target value setting section 26...・Position/force control calculation section 28...Spring constant calculation section 30...Spring constant calculation setting section 32...Press pressure setting window section 33...Spring constant calculation section 36・ 38 ・ 39 ・ 60 ・ Grinding deviation calculation section Averaging processing section End judgment section Force extraction section

Claims (4)

[Claims] (1) A force detecting means for detecting a force on at least one axis applied to the grinding tool, a position detecting means for detecting the position of the grinding tool, and a force detected by each of the force detecting means and the position detecting means. A grinding device comprising a control means for controlling the position and force of the grinding tool using position data, and determining the pressing force of the grinding tool against the workpiece using a virtual spring constant set by the control means, A pressing force setting means for setting the required pressing force, and an arbitrary interval in the moving direction of the grinding tool based on the finishing position of the workpiece and the position data of the grinding tool outputted by the position detecting means. a grinding deviation calculating means for calculating a grinding deviation for each time, and an output value of the pressing force setting means and an output value of the grinding deviation calculating means so that the pressing force becomes a setting value set in the pressing force setting means. and a spring constant calculation setting means for calculating the virtual spring constant and setting the virtual spring constant in the control means. (2) In the pressure-controlled grinding device according to claim 1,
A determining means is provided for taking in the grinding deviation calculated by the grinding deviation calculating means and comparing the calculated grinding deviation with a preset deviation reference value to determine whether to continue or terminate the grinding work. This is a pressure-controlled grinding device that is characterized by: (3) In the pressure-controlled grinding device according to claim 1,
A pressing force control type grinding device, characterized in that a determining means is provided for determining whether to continue or terminate the grinding work based on the force information outputted by the force detecting means. (4) In the pressing force control type grinding device according to any one of claims 1 to 3, the grinding deviation calculating means includes an averaging processing means, and the averaging processing means performs an arbitrary calculation for a specific grinding work section. A pressing force control type grinding device characterized in that an average value of the plurality of grinding deviations obtained for each interval is obtained, and the grinding deviation of this average value is used as an output value of the grinding deviation calculation means.