CN113108750A - Four-oil-pad hydrostatic guideway motion precision evaluation method and system - Google Patents
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
- G01B21/22—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring angles or tapers; for testing the alignment of axes
- G01B21/24—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring angles or tapers; for testing the alignment of axes for testing alignment of axes
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
- G01B21/02—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness
- G01B21/08—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness for measuring thickness
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
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Abstract
The four-oil-pad hydrostatic guideway motion accuracy evaluation method can calculate the motion straightness of the four-oil-pad hydrostatic guideway with larger oil pad center distance; the method comprises the steps of simplifying a hydrostatic guideway model with a large oil pad center distance, performing mathematical expression on a guideway surface error of the hydrostatic guideway, calculating the oil film thickness of a hydrostatic guideway surface profile error, establishing an oil film force calculation model considering the oil pad center distance and a hydrostatic guideway static equilibrium equation, combining the equations to obtain a corresponding relation between the ratio of the oil pad center distance to the guideway surface profile error wavelength and the motion straightness, and solving to obtain the four-oil-pad hydrostatic guideway motion straightness considering the oil pad center distance, so that the motion straightness of the four-oil-pad hydrostatic guideway is more accurately calculated, the slide block motion straightness error can be judged, the four-oil-pad hydrostatic guideway motion precision is evaluated, and theoretical guidance is provided for the four-oil-pad hydrostatic guideway precision design.
Description
Technical Field
The invention relates to the field of hydrostatic guideway errors, in particular to a four-oil-pad hydrostatic guideway motion precision evaluation method and a four-oil-pad hydrostatic guideway motion precision evaluation system.
Background
The hydrostatic guideway is an important functional component of a precision, ultra-precision and three-coordinate measuring machine, and the motion straightness of a guideway slider has important influence on the precision of a machined and measured part. Therefore, the influence rule of the structural parameters of the hydrostatic guideway system on the motion straightness of the slide block needs to be researched, and a theoretical basis is provided for improving the motion straightness. When the structure size of the hydrostatic guideway oil pad is smaller, the hydrostatic guideway oil pad can be respectively simplified into a rigid small wheel, the ratio of the center distance of the oil pad to the profile error wavelength of the guideway surface is 0.5,1.5 and 2.5 … …, and the motion straightness error is zero. However, when the length of the hydrostatic guideway oil pad is large, the hydrostatic guideway oil pad cannot be simplified into a rigid small wheel, otherwise, the error evaluation of relevant structural parameters of the hydrostatic guideway oil pad can be caused, and the motion precision of the hydrostatic guideway with four oil pads cannot be improved.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a four-oil-pad hydrostatic guideway motion accuracy evaluation method and system, which are reasonable in design and simple in method, and can obtain the motion straightness of the four-oil-pad hydrostatic guideway when the center distance of oil pads is larger, thereby greatly improving the motion straightness accuracy of the hydrostatic guideway.
The invention is realized by the following technical scheme:
the four-oil pad hydrostatic guideway motion accuracy evaluation method comprises the following steps,
simplifying a four-oil-pad hydrostatic guideway model with a larger oil pad center distance according to preset conditions;
calculating to obtain a static pressure guide rail surface contour error equation according to the simplified four-oil pad static pressure guide rail model;
obtaining an oil film thickness equation at the oil sealing surface according to the theoretical oil film thickness and the static pressure guide rail surface profile error;
the four-oil-pad hydrostatic guide rail is equivalent to a quasi-static model, an oil film is equivalent to a linear spring unit, and an oil film supporting force equation of the oil pad when the guide rail sliding block moves is obtained according to the thickness of the oil film at the oil seal surface;
according to the balance between the resultant force of the oil film bearing force of each oil pad and the external load, keeping the balance state of the sliding block to obtain a static balance equation of the static pressure guide rail;
and (3) simultaneously establishing a hydrostatic guideway surface profile error equation, an oil film thickness equation, an oil film supporting force equation and a hydrostatic guideway static balance equation, solving to obtain the motion straightness of the hydrostatic guideway, and evaluating the motion precision of the hydrostatic guideway with four oil pads.
Preferably, the preset conditions include assuming that the profile error of the guide surface does not change in the width direction of the oil pad, and neglecting the profile error change of the guide surface in the width x direction of the slider.
Preferably, the static pressure guide rail surface contour error is obtained through calculation according to the simplified four-oil pad static pressure guide rail model, and is represented as follows through Fourier series fitting,
in the formula: e is the error amplitude, λ is the profile error wavelength,
is the phase angle and y is the guide surface profile length.
Preferably, the oil film thickness at the oil seal surface is obtained according to the theoretical oil film thickness and the static pressure guide surface profile error, and the method specifically comprises the following steps:
h(y)＝h0-fz(y)
in the formula: h is0Is the theoretical oil film thickness, fzAnd (y) is the static pressure guide surface contour error.
Preferably, the oil film supporting force of the oil pad when the rail slider moves is specifically expressed as follows,
in the formula: e.g. of the typej(y) is the linear displacement motion error at the center of the oil pad j; e.g. of the typez(y) is the linear displacement motion error of the slide block; thetaxIs the pitch angle error; thetayIs the roll angle error; f. ofej(y) is the action of the sliding block in the moving processThe variable quantity of the oil film bearing force on the oil pad j is determined by the thickness of the oil film at the oil sealing surface; f. ofbj(y) is the oil film bearing force on the oil pad j; a isj、bj、cjIs a directional coefficient, j is 1-4; f. ofjy(y) is the original supporting force of the oil pad when the slide block moves; m is the center distance of the oil pad in the Y direction; and n is the center distance of the oil pad in the X direction.
Preferably, the slider balance state is maintained according to the balance between the resultant force of the oil film bearing forces of the oil pads and the external load, so as to obtain a static balance equation of the hydrostatic guideway, which is specifically as follows:
in the formula (f)j(y) is the original supporting force of the oil pad when the slide block moves; m is the center distance of the oil pad in the Y direction; n is the center distance of the oil pad in the X direction; g is the self weight of the sliding block; w is the load at the machining position; mxIs the resultant moment in the X direction; myThe resultant moment in the Y direction; a isj，bjIs a directional coefficient, j is 1-4; m is1The distance between the machining position and the center of the slide block along the Y direction; n is1The distance between the machining position and the center of the slide block along the X direction.
Preferably, the simultaneous equations are solved to obtain the motion straightness of the hydrostatic guideway as follows:
ez＝B1·A1·(fe1+fe2+fe3+fe4-G-W)
in the formula, A is a slider structure parameter matrix; b is an oil film rigidity coefficient matrix; a. the1Is a first column vector, B1Is a first row vector; e.g. of the typezIs straightness; f. ofejJ is the variation of the oil film bearing force on the oil pad, and j is 1-4; g: self-weight of the sliding block; w: load at the machining location.
The four-oil-pad hydrostatic guideway motion accuracy evaluation system comprises,
the model simplifying module is used for simplifying the four-oil-pad hydrostatic guideway model with larger oil pad center distance according to preset conditions;
the guide rail surface contour error module is used for calculating to obtain a hydrostatic guide rail surface contour error equation according to the simplified four-oil-pad hydrostatic guide rail model;
the oil film thickness module is used for obtaining an oil film thickness equation at the oil sealing surface according to the theoretical oil film thickness and the static pressure guide rail surface profile error;
the oil film supporting force module is used for enabling the four oil pad hydrostatic guide rails to be equivalent to a quasi-static model, enabling the oil films to be equivalent to linear spring units, and obtaining an oil film supporting force equation of the oil pads when the guide rail sliding blocks move according to the thickness of the oil films at the oil sealing surfaces;
the static balance equation module is used for keeping the balance state of the sliding block according to the balance between the resultant force of the oil film bearing force of each oil pad and the external load to obtain a static balance equation of the static pressure guide rail;
and the straightness module is used for simultaneously establishing a hydrostatic guideway surface profile error equation, an oil film thickness equation, an oil film supporting force equation and a hydrostatic guideway static balance equation, solving to obtain the motion straightness of the hydrostatic guideway and evaluating the motion precision of the hydrostatic guideway with four oil pads.
Compared with the prior art, the invention has the following beneficial technical effects:
the four-oil-pad hydrostatic guideway motion accuracy evaluation method can calculate the motion straightness of the four-oil-pad hydrostatic guideway with larger oil pad center distance; the method comprises the steps of simplifying a hydrostatic guideway model with a large oil pad center distance, performing mathematical expression on a guideway surface error of the hydrostatic guideway, calculating the oil film thickness of a hydrostatic guideway surface profile error, establishing an oil film force calculation model considering the oil pad center distance and a hydrostatic guideway static equilibrium equation, combining the equations to obtain a corresponding relation between the ratio of the oil pad center distance to the guideway surface profile error wavelength and the motion straightness, and solving to obtain the four-oil-pad hydrostatic guideway motion straightness considering the oil pad center distance, so that the motion straightness of the four-oil-pad hydrostatic guideway is more accurately calculated, the slide block motion straightness error can be judged, the four-oil-pad hydrostatic guideway motion precision is evaluated, and theoretical guidance is provided for the four-oil-pad hydrostatic guideway precision design.
Drawings
FIG. 1 is a simplified schematic diagram of a hydrostatic guideway model with a large oil pad center distance according to an embodiment of the present invention;
FIG. 2 is a schematic view of the rail profile error and oil pad configuration of the present invention;
FIG. 3 is a schematic illustration of an equivalent mechanical model of the hydrostatic guideway in an example of the present invention;
in the figure: the oil pad 1, the first oil pad 11, the second oil pad 12, the slider 2, a width-direction oil film 21, a length-direction oil film 22, and the guide rail 3.
Detailed Description
The present invention will now be described in further detail with reference to specific examples, which are intended to be illustrative, but not limiting, of the invention.
The invention relates to a four-oil-pad hydrostatic guideway motion precision evaluation method considering an oil pad center distance, which comprises the following steps:
simplifying a four-oil-pad hydrostatic guideway model with a larger oil pad center distance according to preset conditions;
calculating to obtain a static pressure guide rail surface contour error equation according to the simplified four-oil pad static pressure guide rail model;
obtaining an oil film thickness equation at the oil sealing surface according to the theoretical oil film thickness and the static pressure guide rail surface profile error;
the four-oil-pad hydrostatic guide rail is equivalent to a quasi-static model, an oil film is equivalent to a linear spring unit, and an oil film supporting force equation of the oil pad when the guide rail sliding block moves is obtained according to the thickness of the oil film at the oil seal surface;
according to the balance between the resultant force of the oil film bearing force of each oil pad and the external load, keeping the balance state of the sliding block to obtain a static balance equation of the static pressure guide rail;
and (3) simultaneously establishing a hydrostatic guideway surface profile error equation, an oil film thickness equation, an oil film supporting force equation and a hydrostatic guideway static balance equation, solving to obtain the motion straightness of the hydrostatic guideway, and evaluating the motion precision of the hydrostatic guideway with four oil pads.
Specifically, the method comprises the following steps:
s1, aiming at the hydrostatic guide rail with larger oil pad size, simplifying the model of the guide rail slide block,the three-dimensional hydrostatic guide rail is simplified into a two-dimensional guide rail, a sliding block and an oil pad, so that analysis is convenient, and the analysis precision is not influenced in order to simplify the structure. As shown in fig. 1; a first oil pad 11 and a second oil pad 12; m is the center distance between the first oil pad 11 and the second oil pad 12; e.g. of the typez(y) is the displacement motion error of the slide block 13 line; λ is the guide surface profile error wavelength. The center distance of the oil pads is large, and the oil pads are a four-oil pad hydrostatic guideway model which cannot be simplified into small rigid wheels.
S2, assuming that the profile error of the guide surface does not change in the width direction of the oil pad, for example, the guide surface of the hydrostatic guide rail is usually divided into a plurality of sections, each section is equivalent to one oil pad, and the oil pad is provided with an oil film with certain rigidity; fig. 2 shows, among others, a width-direction oil film 21; a longitudinal oil film 22; laIs the length of the oil pad; luThe width of the oil sealing surface in the length direction of the oil pad; lbIs the width of the oil pad; lvThe width of the oil seal surface is the width of the oil pad in the width direction; bwIs the oil film discrete unit width; h is0Theoretical oil film thickness: f. ofz(y) is a guide surface profile tolerance error function;
wherein the profile error function can be fitted to a fourier series, and the rail surface profile error can be expressed as:
in the formula: e is the error amplitude, λ is the profile error wavelength,
is the phase angle and y is the guide surface profile length, where y is a variable.
S3, as shown in fig. 2, if the profile error variation of the guide surface along the slider width x direction is neglected, the oil film thickness at the oil seal surface at any position is:
h(y)＝h0-fz(y)
in the formula: h is0Is the theoretical oil film thickness, fzAnd (y) is a guide surface profile error.
Oil film of oil seal surfaceIs dispersed into N parts with width b along y directionwThe area of the ith unit is set as Ai, the total area of the oil film of the oil sealing surface is set as A, and when the far point o' of the oil pad is at any position, the thickness of the oil film corresponding to the unit is set as h (y)i)，yiThe average oil film thickness at the position corresponding to the ith cell is:
when o 'moves forward from the arbitrary position y, let the volume change amounts of oil films 1 and 2 be Δ V1 and Δ V1, respectively, and when o' moves from the arbitrary position y1 to y2, the change amount of the average oil film thickness is:
then o' at any position y, the average oil film thickness is:
s4, assuming that the lubricating oil is incompressible viscous fluid, the oil pressure p is suppliedsAnd the dynamic viscosity eta of the lubricating oil is constant, h (y) is replaced by ha (y), and the flow resistance of the oil sealing surface meets the following requirements:
if the flow resistance of the throttler is Rc(y), the working pressure of the oil chamber is:
the variation of the oil film bearing capacity is as follows:
fe(y)＝(p0(y)-p0(0))Ae
in the formula, AeIs the effective bearing area of the oil film.
When the guide rail sliding block moves, the four-oil-pad hydrostatic guide rail can be equivalent to a quasi-static model, and an oil film can be simplified into a linear spring unit, so that:
in the formula: e.g. of the typej(y) is the linear displacement motion error at the center of the oil pad j; e.g. of the typez(y) is the linear displacement motion error of the slide block; thetaxIs the pitch angle error; thetayIs the roll angle error; f. ofej(y) is the variation of the oil film bearing force acting on the oil pad j in the movement process of the sliding block; f. ofbj(y) is the oil film bearing force on the oil pad j; a isj、bj、cjIs a directional coefficient, j is 1-4; f. ofjThe (y) is the original supporting force of the oil pad when the slider is moving (distinguished from the oil film supporting force in consideration of the amount of change in the oil film supporting force).
S5, when the sliding block moves to any position, the resultant force of the oil film supporting forces of the oil pads is balanced with the external load, the resultant force and the resultant moment are always 0, the sliding block maintains a balanced state, as shown in fig. 3, the static balance equation of the hydrostatic guideway is:
wherein: k is a radical of1(y)-k4(y) oil film stiffness for four oil pads; e.g. of the type1(y)-e4(y) is the linear displacement motion error at the center of the oil pad of the four oil pads; f. ofj(y) is the original supporting force of the oil pad (different from the oil film supporting force considering the variation of the oil film supporting force) when the slider moves, f1(y)-f4(y) is the oil film bearing force of the four oil pads; m is the center distance between two oil pads in the Y direction; n: the center distance between the two oil pads in the X direction; g: self-weight of the sliding block; w: load at the machining location; m is1: the distance between the machining position and the center of the slide block along the Y direction; n is1: with machining position and centre of slide in X-directionA distance; mxIs the resultant moment in the X direction; myThe resultant moment in the Y direction; a isj，bjIs a directional coefficient, j is 1-4;
s6, combining the static pressure guide rail surface contour error equation, the oil film thickness equation, the oil film supporting force equation and the static pressure guide rail static equilibrium equation in the previous step, and solving the static pressure guide rail motion straightness as follows:
ez＝B1·A1·(fe1+fe2+fe3+fe4-G-W)
in the formula, A is a slider structure parameter matrix; b is an oil film rigidity coefficient matrix; cmIs a direction coefficient matrix; a. the-And B-Inverse matrices to matrices A and B, respectively, A1，A2And A3Is a column vector, B1，B2And B3Is a row vector.
The concrete application of linearity needs to be supplemented, and a simple calculation method cannot be protected as a patent subject.
The invention provides a four-oil-pad hydrostatic guideway motion accuracy evaluation method considering oil pad center distance. By utilizing the advantage of calculating the motion straightness of the four-oil-pad hydrostatic guide rail with the larger oil pad center distance, a four-oil-pad hydrostatic guide rail static analysis model considering the oil pad center distance is provided, and the slide block motion straightness error is solved, so that theoretical guidance is provided for hydrostatic guide rail precision design.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical solution according to the technical idea of the present invention falls within the protection scope of the claims of the present invention.
Claims (8)
1. The method for evaluating the motion accuracy of the four-oil-pad hydrostatic guideway is characterized by comprising the following steps of,
simplifying a four-oil-pad hydrostatic guideway model with a larger oil pad center distance according to preset conditions;
calculating to obtain a static pressure guide rail surface contour error equation according to the simplified four-oil pad static pressure guide rail model;
obtaining an oil film thickness equation at the oil sealing surface according to the theoretical oil film thickness and the static pressure guide rail surface profile error;
the four-oil-pad hydrostatic guide rail is equivalent to a quasi-static model, an oil film is equivalent to a linear spring unit, and an oil film supporting force equation of the oil pad when the guide rail sliding block moves is obtained according to the thickness of the oil film at the oil seal surface;
according to the balance between the resultant force of the oil film bearing force of each oil pad and the external load, keeping the balance state of the sliding block to obtain a static balance equation of the static pressure guide rail;
and (3) simultaneously establishing a hydrostatic guideway surface profile error equation, an oil film thickness equation, an oil film supporting force equation and a hydrostatic guideway static balance equation, solving to obtain the motion straightness of the hydrostatic guideway, and evaluating the motion precision of the hydrostatic guideway with four oil pads.
2. The four-oil-pad hydrostatic guideway motion accuracy evaluation method of claim 1, wherein the preset conditions include assuming that the guideway surface profile error does not change in the oil pad width direction and neglecting the profile error variation of the guideway surface in the slider width x direction.
3. The method for evaluating the motion accuracy of the four-oil-pad hydrostatic guideway according to claim 1, wherein the hydrostatic guideway surface profile error is calculated according to the simplified four-oil-pad hydrostatic guideway model and is represented by Fourier series fitting as follows,
in the formula: e is the error amplitude, λ is the profile error wavelength,
is the phase angle and y is the guide surface profile length.
4. The four-oil-pad hydrostatic guideway motion accuracy evaluation method according to claim 1, wherein the oil film thickness at the oil seal surface is obtained according to the theoretical oil film thickness and the hydrostatic guideway surface profile error, and specifically as follows:
h(y)＝h0-fz(y)
in the formula: h is0Is the theoretical oil film thickness, fzAnd (y) is the static pressure guide surface contour error.
5. The method for evaluating the motion accuracy of a four-oil-pad hydrostatic guideway according to claim 1, wherein the oil film supporting force of the oil pad when the guideway slider moves is specifically expressed as follows,
in the formula: e.g. of the typej(y) is the linear displacement motion error at the center of the oil pad j; e.g. of the typez(y) is the linear displacement motion error of the slide block; thetaxIs the pitch angle error; thetayIs the roll angle error; f. ofej(y) is the oil film supporting force acting on the oil pad j in the sliding block moving processThe variable quantity is determined by the thickness of an oil film at the oil sealing surface; f. ofbj(y) is the oil film bearing force on the oil pad j; a isj、bj、cjIs a directional coefficient, j is 1-4; f. ofjy(y) is the original supporting force of the oil pad when the slide block moves; m is the center distance of the oil pad in the Y direction; and n is the center distance of the oil pad in the X direction.
6. The method for evaluating the motion accuracy of the four-oil-pad hydrostatic guideway according to claim 1, wherein the hydrostatic balance equation of the hydrostatic guideway is obtained by keeping a balanced state of a slider according to the balance between the resultant force of oil film bearing forces of the oil pads and an external load, and is specifically as follows:
in the formula (f)j(y) is the original supporting force of the oil pad when the slide block moves; m is the center distance of the oil pad in the Y direction; n is the center distance of the oil pad in the X direction; g is the self weight of the sliding block; w is the load at the machining position; mxIs the resultant moment in the X direction; myThe resultant moment in the Y direction; a isj，bjIs a directional coefficient, j is 1-4; m is1The distance between the machining position and the center of the slide block along the Y direction; n is1The distance between the machining position and the center of the slide block along the X direction.
7. The four-oil-pad hydrostatic guideway motion accuracy evaluation method according to claim 1, wherein the motion straightness of the hydrostatic guideway is obtained by solving the simultaneous equations as follows:
ez＝B1·A1·(fe1+fe2+fe3+fe4-G-W)
in the formula, A is a slider structure parameter matrix; b is an oil film rigidity coefficient matrix; a. the1Is a first column vector, B1Is a first row vector; e.g. of the typezIs straightness; f. ofejJ is the variation of the oil film bearing force on the oil pad, and j is 1-4; g: self-weight of the sliding block; w: load at the machining location.
8. The four-oil-pad hydrostatic guideway motion accuracy evaluation system is characterized by comprising,
the model simplifying module is used for simplifying the four-oil-pad hydrostatic guideway model with larger oil pad center distance according to preset conditions;
the guide rail surface contour error module is used for calculating to obtain a hydrostatic guide rail surface contour error equation according to the simplified four-oil-pad hydrostatic guide rail model;
the oil film thickness module is used for obtaining an oil film thickness equation at the oil sealing surface according to the theoretical oil film thickness and the static pressure guide rail surface profile error;
the oil film supporting force module is used for enabling the four oil pad hydrostatic guide rails to be equivalent to a quasi-static model, enabling the oil films to be equivalent to linear spring units, and obtaining an oil film supporting force equation of the oil pads when the guide rail sliding blocks move according to the thickness of the oil films at the oil sealing surfaces;
the static balance equation module is used for keeping the balance state of the sliding block according to the balance between the resultant force of the oil film bearing force of each oil pad and the external load to obtain a static balance equation of the static pressure guide rail;
and the straightness module is used for simultaneously establishing a hydrostatic guideway surface profile error equation, an oil film thickness equation, an oil film supporting force equation and a hydrostatic guideway static balance equation, solving to obtain the motion straightness of the hydrostatic guideway and evaluating the motion precision of the hydrostatic guideway with four oil pads.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102490077A (en) * | 2011-12-06 | 2012-06-13 | 厦门大学 | Vertical closed hydrostatic guideway perpendicularity error adjustment device |
| CN110142647A (en) * | 2019-05-20 | 2019-08-20 | 华中科技大学 | A kind of hydrostatic slideway steady-state performance real-time measurement apparatus and method |
-
2021
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102490077A (en) * | 2011-12-06 | 2012-06-13 | 厦门大学 | Vertical closed hydrostatic guideway perpendicularity error adjustment device |
| CN110142647A (en) * | 2019-05-20 | 2019-08-20 | 华中科技大学 | A kind of hydrostatic slideway steady-state performance real-time measurement apparatus and method |
Non-Patent Citations (3)
| Title |
|---|
| JUN ZHA, ET AL.: ""A tolerance design method for hydrostatic guideways motion accuracy based on error averaging effect"", 《PROCEDIA CIRP》 * |
| JUN ZHA, ET AL.: ""Motion straightness of hydrostatic guideways considering the ratio of pad center spacing to guide rail profile error wavelength"", 《INT J ADV MANUF TECHNOL》 * |
| JUN ZHA, ET AL.: ""Straightness error modeling and compensation for gantry type open hydrostatic guideways in grinding machine"", 《INTERNATIONAL JOURNAL OF MACHINE TOOLS AND MANUFACTURE》 * |
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Application publication date: 20210713 |