Machine tool adjustment method and system thereof
11679465 · 2023-06-20
Assignee
Inventors
- Chen-Hui Kuo (Taichung, TW)
- Tian-You Hou (Kaohsiung, TW)
- Jia-Cheng Sun (Changhua County, TW)
- Chen-Yu Kai (Pingtung County, TW)
- Yung-Chih Lin (Taichung, TW)
Cpc classification
G05B19/401
PHYSICS
G05B19/404
PHYSICS
G05B2219/41084
PHYSICS
B23Q17/2233
PERFORMING OPERATIONS; TRANSPORTING
B23Q17/10
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
This disclosure provides a machine tool adjustment method and system thereof. The machine tool adjustment method includes the following steps: enabling a machine tool to perform a circular test; obtaining a measured error value E.sub.m from a measuring instrument, and the measured error value E.sub.m is defined by the difference between the actual circular trajectory and the preset circular trajectory during the circular test; determining an error condition of the tool machine from the measured error value E.sub.m; determining whether the error condition is less than a predetermined criteria; if not, defining a compensation parameter according to the error condition and enabling the machine tool to perform another circular test according to the set compensation parameter until the error condition is less than the predetermined criteria; and if yes, ending the circular test and the machine tool adjustment is finished.
Claims
1. A machine tool adjustment method for adjusting a machine tool comprising a controller, comprising: issuing a circular test instruction to enable the machine tool to perform a circular test; obtaining a measured error value E.sub.m from a measuring instrument, wherein the measured error value E.sub.m is defined by a difference between an actual circular trajectory when the machine tool performs the circular test and a preset circular trajectory; determining an error condition of the machine tool from the measured error value E.sub.m; determining whether the error condition is less than a predetermined criteria; if not, defining a compensation parameter according to the error condition, providing the compensation parameter to the controller to set the compensation parameter to enable the machine tool to perform another circular test according to the compensation parameter that is set, and repeating the above step until it is determined that the error condition is less than the predetermined criteria; and if it is determined that the error condition is less than the predetermined criteria, ending the circular test and completing adjustment of the machine tool; wherein the step of determining the error condition of the machine tool from the measured error value E.sub.m comprises: calculating a radius deviation R.sub.d and an axial offset value A.sub.d from the measured error value E.sub.m; calculating a corrected axis coordinate value from the radius deviation R.sub.d and the axial offset value A.sub.d; and calculating a corrected error value E.sub.c from the corrected axis coordinate value, wherein the measured error value E.sub.m is defined by a difference between an actual radius r.sub.a of the actual circular trajectory when the machine tool performs the circular test and a preset radius r.sub.d of the preset circular trajectory that is set before the circular test is performed; the radius deviation
corrected 1st axis coordinate value x.sub.1′=−1st axial offset value A.sub.d1+(the preset radius r.sub.d+the measured error value E.sub.m−the radius deviation R.sub.d)×cos θ,
corrected 2nd axis coordinate value x.sub.2′=−2nd axial offset value A.sub.d2+(the preset radius r.sub.d+the measured error value E.sub.m−the radius deviation R.sub.d)×sin θ, and θ is between 0 and 360 degrees; and the corrected error value E.sub.c can be calculated through the following formula:
2. The machine tool adjustment method of claim 1, wherein the step of determining the error condition of the machine tool from the measured error value E.sub.m further comprises: looking for a quadrant-passing-through start point A and a protrusion end point B of the machine tool when performing the circular test from a relationship diagram of the corrected error value E.sub.c changing with time; and obtaining a point A error value E.sub.cA of the corrected error value E.sub.c located at the quadrant-passing-through start point A, a point B error value E.sub.cB of the corrected error value E.sub.c located at the protrusion end point B, and calculating a difference between the point A error value E.sub.cA and the point B error value E.sub.cB to obtain a backlash value of the machine tool when performing the circular test, wherein the backlash value reflects the error condition of the machine tool.
3. The machine tool adjustment method of claim 2, wherein the step of determining the error condition of the machine tool from the measured error value E.sub.m further comprises: obtaining a maximum error value E.sub.cM of a maximum value of the corrected error value E.sub.c; and calculating a difference between the maximum error value E.sub.cM and the point B error value E.sub.cB to obtain a protrusion value of the machine tool when performing the circular test, wherein the protrusion value reflects the error condition of the machine tool.
4. The machine tool adjustment method of claim 1, wherein the step of determining that the error condition is not less than the predetermined criteria and defining a compensation parameter according to the error condition comprises: determining that the error condition is quadrant-related, if the error condition is inward quadrant, defining the compensation parameter to be a compensation time according to the error condition and setting the compensation parameter by shortening the compensation time, if the error condition is outward quadrant, defining the compensation parameter to be a compensation amount according to the error condition and setting the compensation parameter by increasing the compensation amount.
5. A machine tool adjustment method for adjusting a machine tool comprising a controller, comprising: issuing a circular test instruction to enable the machine tool to perform multiple circular tests at multiple speeds, respectively; obtaining multiple measured error values respectively by a measuring instrument, wherein the measured error values are defined by a difference between an actual circular trajectory when the machine tool performs each of the multiple circular test at the multiple speeds respectively and a preset circular trajectory respectively generated; determining respective error conditions of the machine tool corresponding to the speeds in performing each of the multiple circular tests according to the measured error values E.sub.m; defining multiple compensation parameters respectively corresponding to the speeds according to each of the error conditions; defining a final compensation parameter according to the compensation parameters; and ending the multiple circular tests, and providing the final compensation parameter to the controller so that the controller completes adjustment of the machine tool according to the final compensation parameter; wherein the step of determining respective error conditions of the machine tool corresponding to the speeds in performing the circular test comprises: calculating a radius deviation R.sub.d and an axial offset value A.sub.d from the measured error value E.sub.m; calculating a corrected axis coordinate value from the radius deviation R.sub.d and the axial offset value A.sub.d; and calculating a corrected error value E.sub.c from the corrected axis coordinate value, wherein the measured error value E.sub.m is defined by a difference between an actual radius r.sub.a of the actual circular trajectory when the machine tool performs the circular test and a preset radius r.sub.d of the preset circular trajectory that is set before the circular test is performed; the radius deviation
corrected 1st axis coordinate value x.sub.1′=−1st axial offset value A.sub.d1+(the preset radius r.sub.d+the measured error value E.sub.m−the radius deviation R.sub.d)×cos θ,
corrected 2nd axis coordinate value x.sub.2′=−2nd axial offset value A.sub.d2+(the preset radius r.sub.d+the measured error value E.sub.m−the radius deviation R.sub.d)×sin θ, and θ is between 0 and 360 degrees; and the corrected error value E.sub.c can be calculated through the following formula:
6. The machine tool adjustment method of claim 5, wherein the step of determining respective error conditions of the machine tool corresponding to the speeds in performing the circular test further comprises: looking for a quadrant-passing-through start point A and a protrusion end point B of the machine tool when performing the circular test from a relationship diagram of the corrected error value E.sub.c changing with time; and obtaining a point A error value E.sub.cA of the corrected error value E.sub.c located at the quadrant-passing-through start point A, a point B error value E.sub.cB of the corrected error value E.sub.c located at the protrusion end point B, and calculating a difference between the point A error value E.sub.cA and the point B error value E.sub.cB to obtain a backlash value of the machine tool when performing the circular test, wherein the backlash value reflects the error condition of the machine tool.
7. The machine tool adjustment method of claim 5, wherein the step of determining respective error conditions of the machine tool corresponding to the speeds in performing the circular test further comprises: obtaining a maximum error value E.sub.cM of a maximum value of the corrected error value E.sub.c; and calculating a difference between the maximum error value E.sub.cM and the point B error value E.sub.cB to obtain a protrusion value of the machine tool when performing the circular test, wherein the protrusion value reflects the error condition of the machine tool.
8. A machine tool adjustment system for adjusting a machine tool, comprising: a memory configured to store an error analysis module and an error compensation module; and a processor coupled to the memory and configured to execute the error analysis module and the error compensation module, wherein the processor executes the error analysis module to perform the following steps: obtaining a measured error value E.sub.m from a measuring instrument, wherein the measured error value E.sub.m is defined by a difference between an actual circular trajectory when the machine tool performs the circular test and a preset circular trajectory; and determining an error condition of the machine tool from the measured error value E.sub.m; and the processor executes the error compensation module to perform the following steps: determining whether the error condition is less than a predetermined criteria; if not, defining a compensation parameter according to the error condition, and providing the compensation parameter to a controller of the machine tool to set the compensation parameter so that the machine tool starts another circular test according to the set compensation parameter and repeats the above step until it is determined that the error condition is less than the predetermined criteria; and if it is determined that the error condition is less than the predetermined criteria, notifying the controller of the machine tool to end the circular test and complete adjustment of the machine tool; wherein the processor executes the error analysis module to further perform the following steps: calculating a radius deviation R.sub.d and an axial offset value A.sub.d from the measured error value E.sub.m; calculating a corrected axis coordinate value from the radius deviation R.sub.d and the axial offset value A.sub.d; and calculating a corrected error value E.sub.c from the corrected axis coordinate value, wherein the measured error value E.sub.m is defined by a difference between an actual radius r.sub.a of the actual circular trajectory when the machine tool performs the circular test and a preset radius r.sub.d of the preset circular trajectory that is set before the circular test is performed; the radius deviation
corrected 1st axis coordinate value x.sub.1′=−1st axial offset value A.sub.d1+(the preset radius r.sub.d+the measured error value E.sub.m−the radius deviation R.sub.d)×cos θ,
corrected 2nd axis coordinate value x.sub.2′=−2nd axial offset value A.sub.d2+(the preset radius r.sub.d+the measured error value E.sub.m−the radius deviation R.sub.d)×sin θ, and θ is between 0 and 360 degrees; and the corrected error value E.sub.c can be calculated through the following formula:
9. The machine tool adjustment system of claim 8, wherein the processor executes the error analysis module to further perform the following steps: looking for a quadrant-passing-through start point A and a protrusion end point B of the machine tool when performing the circular test from a relationship diagram of the corrected error value E.sub.c changing with time; and obtaining a point A error value E.sub.cA of the corrected error value E.sub.c located at the quadrant-passing-through start point A, a point B error value E.sub.cB of the corrected error value E.sub.c located at the protrusion end point B, and calculating a difference between the point A error value E.sub.cA and the point B error value E.sub.cB to obtain a backlash value of the machine tool when performing the circular test, wherein the backlash value reflects the error condition of the machine tool.
10. The machine tool adjustment system of claim 8, wherein the processor executes the error analysis module to further perform the following steps: obtaining a maximum error value E.sub.cM of a maximum value of the corrected error value E.sub.c; and calculating a difference between the maximum error value E.sub.cM and the point B error value E.sub.cB to obtain a protrusion value of the machine tool when performing the circular test, wherein the protrusion value reflects the error condition of the machine tool.
11. The machine tool adjustment system of claim 8, wherein the processor executes the error compensation module to further perform the following steps: determining that the error condition is not less than the predetermined criteria and determining that the error condition is quadrant-related, if the error condition is inward quadrant, defining the compensation parameter to be a compensation time according to the error condition and setting the compensation parameter by shortening the compensation time, if the error condition is outward quadrant, defining the compensation parameter to be a compensation amount according to the error condition and setting the compensation parameter by increasing the compensation amount.
12. The machine tool adjustment system of claim 8, wherein the processor executes the error compensation module to further perform the following steps: defining multiple compensation parameters according to multiple measured error values obtained from the circular test that is performed corresponding to multiple speeds respectively; defining a final compensation parameter according to the compensation parameters; and providing the final compensation parameter to the controller of the machine tool to complete adjustment of the machine tool.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
DESCRIPTION OF EMBODIMENTS
(11) Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
(12)
(13) In this embodiment, the processor 11 may be, for example, a central processing unit (CPU), or other programmable general-purpose or specific-purpose microprocessor, digital signal processor (DSP), programmable controller, application specific integrated circuits (ASIC), programmable logic device (PLD), other similar processing devices, or a combination of these devices.
(14) In this embodiment, the memory 13 may be, for example, a dynamic random access memory (DRAM), a flash memory, or a non-volatile random access memory (NVRAM), etc. In this embodiment, the error analysis module 131 and the error compensation module 133 may be, for example, a software application. Therefore, the memory 13 can store the error analysis module 131 and the error compensation module 133 in advance for the processor 11 to access and execute. It should be noted that, in another embodiment, the error analysis module 131 and the error compensation module 133 may also be stored in a non-transitory computer-readable storage medium. By loading the error analysis module 131 and the error compensation module 133 into a computer device, the machine tool adjustment method described in the embodiments of the present disclosure can be implemented.
(15) Please refer to
(16)
(17) In another embodiment, after the machine tool 2 completes the first circular test, if the result of the circular test shows that the circular servo is not synchronized and the parameters of the axes are not consistent, the operator can check and adjust the parameters set by the controller 23 through the human-machine interface of the machine tool adjustment system 1 to confirm the parameters, for example, including position gain, speed gain, position feedforward, acceleration and deceleration time, etc., that cause servo asynchronization, and after the parameters are adjusted and the servo synchronization is confirmed, then the circular test is performed again (step S210).
(18) Next, in step S230, the machine tool adjustment system 1 can obtain the measured error value E.sub.m from the measuring instrument 3 disposed on the machine tool mechanism 21. The measured error value E.sub.m is defined by the difference between the actual circular trajectory when the machine tool 2 performs the current circular test and the preset circular trajectory (set before performing step S210). After the preset circular time T (for example, it can be the time of circulating for two circles, that is, T=4π*preset radius/circular speed) has passed, the machine tool adjustment system 1 will automatically send a signal to notify the controller 23 of the machine tool 2 that the circular test has been completed. Meanwhile, the processor 11 of the machine tool adjustment system 1 executes the error analysis module 131 pre-stored in the memory 13 to perform step S240: defining the error condition of the machine tool 2 from the measured error value E.sub.m.
(19) Please refer to
(20) As shown in
(21) More specifically, in this embodiment, in step S341, the measured error value E.sub.m can be defined by the difference between the actual radius r.sub.a of the actual circular trajectory when the machine tool 2 performs the circular test and the preset radius r.sub.d of the preset circular trajectory that is set before the circular test is performed (i.e., the measured error value E.sub.m=actual radius r.sub.a−preset radius r.sub.d). The measured error value E.sub.m will change with time as the circular test goes on. As shown in
(22) Moreover, in step S341, the radius deviation amount R.sub.d and the axial offset value A.sub.d can be further calculated by the following formula:
(23)
n is the number of times of obtaining the measured error value E.sub.m; and
(24)
E.sub.m′ is uniaxial component of the measured error value E.sub.m.
(25) Then, the processor 11 of the machine tool adjustment system 1 executes the error analysis module 131 which can be stored in the memory 13 in advance to perform step S343: calculating the corrected axis coordinate value from the radius deviation R.sub.d and the axial offset value A.sub.d. Please note that when the machine tool 2 performs this circular test, the measured error value E.sub.m corresponding to each time point can be obtained through the measuring instrument 3, and then the uniaxial component of the measured error value E.sub.m can be obtained through calculation, i.e., the 1st axis coordinate value x.sub.1 of the first axis (for example, the X axis in a rectangular coordinate system) and the 2nd axis coordinate value x.sub.2 of the second axis for example, the Y axis in a rectangular coordinate system), thereby obtaining the error condition of the machine tool 2 (more specifically, the end of machine tool mechanism 21). The 1st axis coordinate value x.sub.1 and the 2nd axis coordinate value x.sub.2 corresponding to the measured error value E.sub.m can be calculated through the following formula:
1st axis coordinate value x.sub.1=(preset radius r.sub.d+measured error value E.sub.m)×cos θ; and
2nd axis coordinate value x.sub.2=(preset radius r.sub.d+measured error value E.sub.m)×sin θ, and θ is between 0 and 360 degrees.
(26) However, if correction is not made, the measured error value E.sub.m obtained directly through the measuring instrument 3 and the circular trajectory generated corresponding to uniaxial component (the first axis coordinate value and the second axis coordinate value) may appear oblique or non-circular. Therefore, in this embodiment, the corrected axis coordinate value is obtained through calculation in step S343, so as to better define the error condition of the machine tool 2 subsequently.
(27) More specifically, in this embodiment, in step S343, the corrected axis coordinate value can be calculated through the following formula:
corrected 1st axis coordinate value x.sub.1′=−1st axial offset value A.sub.d1+(preset radius r.sub.d+measured error value E.sub.m−radius deviation R.sub.d)×cos θ; and
corrected 2nd axis coordinate value x.sub.2′=−2nd axial offset value A.sub.d2+(preset radius r.sub.d+measured error value E.sub.m−radius deviation R.sub.d)×sin θ.
(28) Then, the processor 11 of the machine tool adjustment system 1 executes the error analysis module 131 that can be stored in the memory 13 in advance to perform step S345: calculating the corrected error value E.sub.c from the corrected axis coordinate values. The corrected error value E.sub.c corresponds to the measured error value E.sub.m, and will change with time as the circular test goes on, as shown in
(29) More specifically, in this embodiment, the corrected error value E.sub.c can be calculated through the corrected 1st axis coordinate value x.sub.1′ and the corrected 2nd axis coordinate value x.sub.2′ obtained from the previous step S343 as well as the following formula:
(30)
(31) After completing step S345, the corrected error value within a period of time is obtained from
(32) Please refer to
(33) In
(34) In
(35) Please refer back to
(36) As shown in
(37) If it is determined that the error condition is less than the predetermined criteria, for example, the calculated backlash value is less than the set backlash value, according to an embodiment of the present disclosure, the machine tool adjustment method proceeds to step S260: end the circular test and complete the adjustment. More specifically, in step S260, the processor 11 of the machine tool adjustment system 1 executes the error compensation module 133 that can be stored in the memory 13 in advance, and notifies the controller 23 of the machine tool 2 to end the circular test, thereby completing adjustment of the machine tool 2.
(38) In step S250, if the processor 11 of the machine tool adjustment system 1 executes the error compensation module 133 and determines that the error condition of the machine tool 2 is not less than the predetermined criteria, for example, the calculated protrusion value is greater than the set protrusion value, then proceed to step S270: determining compensation parameters according to the error condition.
(39) Next, please refer to
(40) As shown in
(41) If it is determined in step S771 that the error condition is quadrant-related and the error condition of the machine tool 2 is determined to be inward quadrant, the corresponding compensation parameter is defined to be the compensation time, and subsequently the machine tool adjustment system 1 will notify the controller of the machine tool 2 to set the compensation parameter by shortening the compensation time (step S773). On the other hand, if the error condition of the machine tool 2 is determined to be outward quadrant, then the corresponding compensation parameter is defined to be the compensation amount, and subsequently the machine tool adjustment system 1 will notify the controller of the machine tool 2 to set the compensation parameter by increasing the compensation amount (step S775).
(42) In addition, please refer to
(43) Specifically, as shown in
(44) Please note here that the first speed and the second speed shown in
(45) Please refer back to
(46) Please note that, as shown in
(47) Specifically, in this embodiment, in step S220, the processor 11 of the machine tool adjustment system 1 may provide the compensation parameters obtained in the previous step to the controller 23 of the machine tool 2 to set the compensation parameters through error compensation module 133 stored in the memory 13 in advance, so that the machine tool 2 starts to perform the next circular test according to the set compensation parameters. Then, the steps S230, S240, S250, and S270 described above are repeated until in step S250 the machine tool adjustment system 1 determines that the error condition of the machine tool 2 is less than the predetermined criteria, and then proceeds to step S260. The machine tool adjustment system 1 notifies the controller of the machine tool 2 to end the circular test. At this stage, the machine tool 2 has completed the adjustment according to the machine tool adjustment method described in this disclosure.
(48) In this way, the machine tool adjustment method and system of the present disclosure can automatically measure and automatically determine the error conditions of the machine tool 2, such as the backlash value and the protrusion value, etc.; moreover, automatic measurement is performed repeatedly through the method in the present disclosure to perform corresponding compensation so as to adjust the machine tool 2. The machine tool adjustment system 1 can find the optimal compensation parameters at a fixed speed, and can also find the compensation parameters applicable at various speeds.
(49) In summary, the machine tool adjustment method and the system thereof described in the present disclosure can automatically determine the error conditions of the circular movement of the machine tool 2 with respect to the end of the actual machine tool mechanism 21, automatically make compensation according to the error conditions, and optimize the compensation parameters, thereby reducing the time for adjusting the machine tool 2 and further improving the overall performance of the machine tool 2 to ensure the machining accuracy.
(50) Although the present disclosure has been disclosed in the above embodiments, it is not intended to limit the present disclosure, and those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the disclosure. Therefore, the scope to be protected by the present disclosure is subject to the scope defined by the appended claims.