CN-120516587-B - Online dressing method of grinding wheel and lead screw machining device

CN120516587BCN 120516587 BCN120516587 BCN 120516587BCN-120516587-B

Abstract

The application relates to the technical field of high-precision planetary roller screw machining, in particular to an online dressing method of a grinding wheel and a screw machining device. The dressing method comprises the step of reversely pushing the abrasion loss of the grinding wheel according to the pitch diameter change of the screw rod sample piece, and comprises the steps of detecting the pitch diameter D 1 of the screw rod sample piece in real time, and meeting the condition that when a pitch diameter error value delta D of the reference pitch diameter D 2 of the screw rod sample piece exceeds a preset pitch diameter error threshold value, delta R max = (delta D multiplied by tan theta)/2 is met, wherein delta R max is the maximum radius of the grinding wheel, D (X) ＝d 0 +η×(ΔR max -ΔR (X) is the dressing depth of the dressing wheel at each position in the axial direction of the grinding wheel. The online dressing method and the lead screw machining device of the grinding wheel solve the problem that the traditional online dressing mode of the grinding wheel cannot dynamically adapt to the abrasion gradient of the grinding wheel, so that over-dressing/under-dressing is caused.

Inventors

LI JIANPING
LI MENG
ZHANG HUIXUE
ZHENG TAO
LI MINGZHI
LIU HUWEI
WANG CONG
ZHANG JUN
GUO YUTING

Assignees

中国机械总院集团宁波智能机床研究院有限公司
象山县机械科学研究总院南方中心

Dates

Publication Date: 20260505
Application Date: 20250519

Claims (10)

1. An online dressing method of a grinding wheel is characterized in that the grinding wheel is used for processing a screw rod sample, and the grinding wheel can be dressed by a dressing wheel while processing the screw rod sample; the online dressing method of the grinding wheel comprises the following steps: reversely pushing the abrasion loss of the grinding wheel according to the pitch diameter change of the screw rod sample; the step of reversely pushing the abrasion loss of the grinding wheel according to the pitch diameter change of the screw rod sample piece comprises the following steps: Detecting the pitch diameter D 1 of the screw rod sample in real time, and when the pitch diameter error value delta D of the reference pitch diameter D 2 of the screw rod sample and the D 1 exceeds a preset pitch diameter error threshold value, satisfying the following conditions: ΔR max =(ΔD×tanθ)/2; Wherein DeltaR max is the maximum radius of the grinding wheel, deltaD is the pitch diameter error of the screw rod sample piece, and theta is the reference thread form angle of the screw rod sample piece; d (X) ＝d 0 +η×(ΔR max -ΔR (X) ); wherein d (X) is the dressing depth of the dressing wheel on each axial position of the grinding wheel, d 0 is the reference dressing depth of the dressing wheel, eta is the gradient compensation coefficient, and DeltaR (X) is the radius of each axial position of the grinding wheel.
2. The on-line dressing method of a grinding wheel according to claim 1, wherein the step of reversely pushing the abrasion loss of the grinding wheel according to the change in pitch diameter of the screw sample further comprises: calculating the evolution of the radius of each axial position of the grinding wheel along with space and time based on a physical mechanism of the abrasion of the grinding wheel in the grinding process by a component differential equation; Wherein F n(x,t) is normal grinding force, V (x,t) is linear speed of the grinding wheel, and k p is wear rate coefficient of the grinding wheel.
3. The on-line dressing method for a grinding wheel according to claim 2, further comprising: compensating the abrasion loss of the grinding wheel at one time according to the material of the grinding wheel; The step of compensating the abrasion loss of the grinding wheel at a time according to the material of the grinding wheel comprises the following steps: Δd error ＝β×(G/G 0 )×(B/B 0 )^γ; Wherein Δd error is the abrasion loss of the grinding wheel which is compensated once, G is the actual granularity of the grinding wheel, G 0 is the reference granularity of the grinding wheel, B is the binder hardness of the grinding wheel, B 0 is the reference hardness of the grinding wheel, and β and γ are the material characteristic correction coefficients of the grinding wheel; The total dressing depth d Total (S) ＝d (X) +Δd error of the dressing wheel is then.
4. The on-line dressing method for a grinding wheel according to claim 3, further comprising: The dressing speed of the dressing grinding wheel is adjusted; The dressing speed adjustment of the dressing grinding wheel comprises the following steps: detecting the actual radial dressing force F real of the dressing grinding wheel in real time, and when F real exceeds a target radial dressing force threshold of the target radial dressing force F target , meeting the following conditions: V new ＝V old ×(F target /F real )^k; Wherein V new is the dressing speed after the adjustment of the dressing wheel, V old is the dressing speed before the adjustment of the dressing wheel, F target is the target radial dressing force of the dressing wheel, F real is the actual radial dressing force of the dressing wheel, and k is the material damping coefficient of the grinding wheel.
5. The on-line dressing method for a grinding wheel according to claim 4, further comprising: Secondarily compensating the abrasion loss of the grinding wheel according to the fluctuation of the dressing force; the step of secondarily compensating the abrasion loss of the grinding wheel according to the dressing force fluctuation includes: Δd=[α×(F real -F target )]-Δd error ; Wherein Δd is the abrasion loss of the secondary compensation grinding wheel, and α is the dressing force displacement conversion coefficient; the total dressing depth d Total (S) ＝d (X) +Δd of the dressing wheel.
6. The screw machining device is characterized by comprising a grinding wheel, a dressing wheel and a screw sample; The grinding wheel is used for processing the screw rod sample piece, and the grinding wheel can be dressed by a dressing wheel when processing the screw rod sample piece; The dressing method of the dressing wheel to the grinding wheel adopts the on-line dressing method of the grinding wheel according to claim 5.
7. The lead screw machining device of claim 6, further comprising a lead screw pitch diameter gauge; And the lead screw pitch diameter measuring instrument detects the pitch diameter D 1 of the lead screw sample in real time.
8. The lead screw machining device of claim 7, further comprising a plurality of force sensors; The force sensors are arranged at intervals along the outer edge of one side of the dressing grinding wheel, the force sensors detect radial dressing force of the dressing grinding wheel in real time, and the average value of the radial dressing force detected by the force sensors in real time is the actual radial dressing force F real .
9. The lead screw machining device of claim 8, further comprising a first slip and a second slip; The first sliding table can drive the dressing grinding wheel to move along the radial direction of the grinding wheel, and the second sliding table can drive the dressing grinding wheel to move along the axial direction of the grinding wheel so as to dress the grinding wheel.
10. The lead screw machining device of claim 9, further comprising a numerical control system; the numerical control system receives the data sent by the force sensor and the lead screw pitch diameter measuring instrument and according to delta R max ＝(ΔD×tanθ)/2,d (X) ＝d 0 +η×(ΔR max -ΔR (X) ), Calculating total dressing depth d Total (S) ＝d (X) +Deltad of each axial position of the dressing grinding wheel, wherein the numerical control system controls the first sliding table and the second sliding table to dress the grinding wheel according to the total dressing depth d Total (S) of each axial position of the dressing grinding wheel; In the dressing process, if the numerical control system judges that F real exceeds the target radial dressing force threshold of the target radial dressing force F target , the numerical control system calculates the regulated dressing speed V new of the dressing grinding wheel according to V new ＝V old ×(F target /F real )/(k), and controls the speed of the dressing grinding wheel to be regulated to V new according to the regulated dressing speed V new .

Description

Online dressing method of grinding wheel and lead screw machining device Technical Field The application relates to the technical field of high-precision planetary roller screw machining, in particular to an online dressing method of a grinding wheel and a screw machining device. Background The machining precision of the thin-wall deep hole planetary roller screw rod for military or humanoid robots is extremely high and needs to be controlled to be at least +/-1 mu m. In the existing machining process of the thin-wall deep hole planetary roller screw, the grinding wheel is machined through the grinding wheel, and the grinding wheel is real-time dressed through the dressing wheel during machining, but the traditional online dressing mode of the grinding wheel has the following problems: The traditional online dressing method of the grinding wheel has rough control quantity, is based on fixed parameter dressing, and cannot dynamically adapt to the abrasion gradient of the grinding wheel, so that over-dressing/under-dressing is caused. Disclosure of Invention The application aims to provide an online dressing method of a grinding wheel and a lead screw machining device, so that the problems that the traditional online dressing mode of the grinding wheel is rough in control quantity, depends on fixed parameters for dressing, cannot dynamically adapt to the abrasion gradient of the grinding wheel and causes over-dressing/under-dressing are solved. According to a first aspect of the present application, there is provided an on-line dressing method of a grinding wheel for machining a screw sample, the grinding wheel being capable of being dressed by a dressing wheel while machining the screw sample; the online dressing method of the grinding wheel comprises the following steps: reversely pushing the abrasion loss of the grinding wheel according to the pitch diameter change of the screw rod sample; the step of reversely pushing the abrasion loss of the grinding wheel according to the pitch diameter change of the screw rod sample piece comprises the following steps: Detecting the pitch diameter D 1 of the screw rod sample in real time, and when the pitch diameter error value delta D of the reference pitch diameter D 2 of the screw rod sample and the D 1 exceeds a preset pitch diameter error threshold value, satisfying the following conditions: Δr max = (Δd×tan θ)/2, where Δr max is the maximum radius of the grinding wheel, Δd is the pitch diameter error of the screw sample, and θ is the reference thread profile angle of the screw sample; d (X)＝d0+η×(ΔRmax-ΔR(X)), wherein d (X) is the dressing depth of the dressing wheel on each axial position of the grinding wheel, d 0 is the reference dressing depth of the dressing wheel, eta is the gradient compensation coefficient, and DeltaR (X) is the radius of each axial position of the grinding wheel. In any of the above technical solutions, further, the step of reversely pushing the abrasion loss of the grinding wheel according to the pitch diameter change of the screw rod sample piece further comprises the steps of calculating the evolution of the radius of each axial position of the grinding wheel along with the space and time based on a physical mechanism of abrasion of the grinding wheel in the grinding process by a component differential equation; Wherein F n(x,t) is normal grinding force, V (x,t) is linear speed of the grinding wheel, and k p is wear rate coefficient of the grinding wheel. In any of the above technical solutions, the on-line dressing method of a grinding wheel further includes the step of compensating the abrasion loss of the grinding wheel once according to the material of the grinding wheel, and the step of compensating the abrasion loss of the grinding wheel once according to the material of the grinding wheel includes: Δderror＝β×(G/G0)×(B/B0)^γ; Wherein Δd error is the abrasion loss of the grinding wheel which is compensated once, G is the actual granularity of the grinding wheel, G 0 is the reference granularity of the grinding wheel, B is the binder hardness of the grinding wheel, B 0 is the reference hardness of the grinding wheel, and β and γ are the material characteristic correction coefficients of the grinding wheel; The total dressing depth d Total (S) ＝d(X)+Δderror of the dressing wheel is then. In any of the above technical solutions, the on-line dressing method of the grinding wheel further includes a dressing speed adjustment of the dressing wheel, wherein the dressing speed adjustment of the dressing wheel includes: detecting the actual radial dressing force F real of the dressing grinding wheel in real time, and when F real exceeds a target radial dressing force threshold of the target radial dressing force F target, meeting the following conditions: V new＝Vold×(Ftarget/Freal)/(k), wherein V new is the dressing speed after the adjustment of the dressing wheel, V old is the dressing speed before the adjustment of the dressing wheel, F