JPH11123633A - Working method of scroll lap and working device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately judge the thickness of a scroll lap by extracting not only a deviation on a shape but also a deviation on a dimension, and to adjust a working device on abrasion of a tool by collectively converting a measuring coordinate point sequence of an outer line and an inner line into coordinates. SOLUTION: When abrasion of a tool used for work proceeds, a diameter of the tool reduces, causing a scroll lap becoming thick, reduction in a radius of the tool can be seized as an average of a thickness deviation. An average ΔT of this thickness deviation is determined by expressions I to III, and is set as an average thickness. Data on the tool diameter of a working device or data on a tool offset or data on a tool locus is corrected in the direction for eliminating the average thickness ΔT. ΔSm' and ΔUi' are a deviation ΔSm' and ΔUi' of a measuring coordinate point and a design value, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for processing a scroll wrap, and more particularly, to a method for processing a scroll wrap of an orbiting scroll and a fixed scroll forming a compression chamber of a scroll compressor. The present invention relates to a scroll wrap processing method and apparatus for correcting a processing machine by accurately and efficiently measuring the accuracy of the shape, position and dimensions of a scroll wrap defined by an involute curve.

[0002]

2. Description of the Related Art First, an orbiting scroll and a fixed scroll which are objects of the present invention will be described with reference to FIG. FIG. 8 is a perspective view showing the appearance of the scroll wrap,
(A) is a perspective view of an orbiting scroll, and (b) is a perspective view of a fixed scroll. The orbiting scroll 20 and the fixed scroll 21, which are shown in FIGS. 8A and 8B, respectively, are used in a scroll compressor such as an air conditioner. It has the function of compressing gas.

The scroll wrap 2 of the orbiting scroll 20
Numeral 0a is formed by a spiral wall having a thickness defined by the involute curve, and the same is true of the scroll wrap 21a of the fixed scroll 21 that forms a pair. Since the scroll wraps 20a and 21a are combined with each other to form a compression chamber requiring confidentiality, high precision is required. Usually, this scroll wrap is finished by machining, but the processed scroll wrap 20a,
The precision of 21a was measured, and based on the result obtained by the measurement, the portion to be adjusted by the processing apparatus and the amount were determined and adjusted, and the subsequent processing was performed.

As an example of a method and an apparatus for obtaining measurement data for processing the scroll wraps 20a and 21a, for example, as disclosed in JP-A-60-52702, a rotary table and a linear movement axis are combined. There was a method and apparatus for measuring together. This measuring method and apparatus
Utilizing the characteristic that the involute curve is an extension line of the base circle, the configuration related to the shape was measured. The processing of the scroll wrap has been performed by combining the measuring method and apparatus as in the prior art with the processing apparatus.

[0005]

In the processing of a scroll wrap, among the items that need to be measured accurately in order to adjust the processing device, the most important items are shape deviation, thickness deviation, and the like. These are the deviation of the base circle center position and the deviation of the phase angle. However, the configuration of the apparatus for measuring accuracy by combining a rotary table and a linear movement axis disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 60-52702 is mainly configured to measure a deviation of a shape. No consideration was given to measuring the above item, and in particular, there was no configuration for obtaining accurate data regarding the deviation of the thickness and the deviation of the phase angle.

[0006] The first problem of the prior art is as follows. In measuring the scroll wrap, it is necessary to evaluate the outer line, which is the outer wall of the scroll wrap, and the inner line, which is the inner wall. In evaluating the shape, it is customary to evaluate the deviation from the design value of the coordinate point sequence obtained by the measurement. Here, the scroll wrap has a deviation between the center position of the base circle and the phase angle due to the displacement of the machined device or the like, which is inconvenient for evaluating the shape. Therefore, a measure is taken to exclude the deviation between the center position of the base circle and the phase angle by calculation, and only the deviation of the shape is extracted and evaluated.

[0007] In this process, in order to make the state optimal for evaluation of the shape of the scroll wrap, it has been customary to independently convert the measured coordinate point sequences of the outer line and the inner line, respectively, and evaluate them. Since the outer line and the inner line are separately coordinate-transformed, the relative positions of the measured coordinate point sequences of the outer line and the inner line are shifted. Therefore, there is a problem that the deviation of the thickness caused by the wear of the tool or the like cannot be determined, and the evaluation result of the phase angle has a large error.

A first object of the present invention is to solve the above-mentioned first problem, in which only one set of coordinate transformation amounts of parallel movement and rotation movement is obtained, and this is used as a deviation from a reference. By this, it is possible to easily and accurately obtain data for adjusting the processing device from the measurement data, and to provide a scroll wrap processing method and a processing device capable of efficiently obtaining a scroll wrap with good accuracy. It is in.

[0009] The second problem is as follows.
The amount and direction of the coordinate transformation described in the above example is equal to the deviation of the scroll wrap from the reference. Deviations from this reference include a deviation of the center of the base circle and a deviation of the phase angle, and knowing these values makes it possible to correct the processing apparatus. However, conventionally, since the coordinate line sequence of the measured coordinate points of the outer line and the inner line is separately converted, two kinds of deviations between the base circle center position and the phase angle are obtained. In other words, there are two kinds of deviations: one difference between the center position of the base circle of the outer line and the phase angle and one difference between the center position of the base circle of the inner line and the phase angle.

On the other hand, the outer and inner lines of the scroll wrap are
It is common to perform continuous machining by a single-stroke operation under the same machining apparatus, the same tool, and the same coordinate system. Therefore, there is only one displacement state of the processing device. From the result of measuring the scroll wrap machined in this one kind of displacement state, the value to be used for correcting the machining apparatus is 2
There was a terrible problem to find out.

Because of the first and second problems described above,
Although the shape deviation was obtained with the conventional measurement unit,
It was impossible to obtain deviations of the base circle center position, phase angle and thickness. For this reason, in order to know the adjustment amount of the deviation between the base circle center position and the phase angle that cannot be determined from the processed scroll wrap, the position measurement of each axis of the processing device and the angle measurement of the rotation axis are performed on behalf of the processing device. Since the operation was stopped, the productivity was significantly impaired. Also, the thickness deviation needs to be measured using another dimension measuring device, for example, a dimension measuring device such as a micrometer,
There is a problem that the number of steps is large and the accuracy is poor.

A second object of the present invention is to solve the second problem described above, and uses both data of an outside line and an inside line to perform coordinate transformation, and then calculates a deviation between a design value and a measured value. A scroll wrap processing method and a processing method capable of easily and accurately obtaining a deviation including a thickness, which can be obtained, and thus thickness adjustment data generated due to a decrease in a tool diameter due to tool wear. It is to provide a device.

Further, the third problem is as follows. In order to obtain a design value corresponding to the measurement coordinate point, data on the design value is required. Conventionally, a general-purpose method that can be used without being limited to an involute curve has been generally used. In this method, a design value is given not by a mathematical expression but by a coordinate point. When a measurement point corresponding to the design value is obtained, a general-purpose curve is applied and a process of performing an approximate calculation is used. Since the involute curve was not used in curve fitting, it caused calculation errors.In particular, the calculation error increased as the distance between the design values and the measurement coordinate points increased. Was.

A third object of the present invention is to solve the third problem described above. By obtaining a design value from a design equation of an involute curve, it is possible to improve the evaluation accuracy of measurement data as compared with the prior art. It is an object of the present invention to provide a scroll wrap processing method and a processing apparatus thereof, which can improve the processing accuracy.

The fourth problem is as follows. In the configuration of the measurement unit described above, the rotation center of the rotary table exists at only one point, but when the structural member of the measurement unit is thermally displaced due to a change in the environmental temperature, the relative position between the linear axis and the center of the rotary table is displaced. In the involute curve, since the length and the angle are equivalent, the displacement of the center of the rotary table is evaluated as an error of the phase angle. Therefore, there is a problem that a measurement error of a phase angle instead of a position occurs due to the thermal displacement.

A fourth object of the present invention is to solve the above-mentioned fourth problem, and it is possible to exclude the influence of thermal displacement of the measuring unit, and to achieve high accuracy even in a poor processing site environment. It is an object of the present invention to provide a scroll wrap processing method and a processing apparatus capable of performing accurate measurement.

In view of the above, it is an object of the present invention to evaluate the shape, position and thickness of a scroll wrap with a measuring unit using a rotary table, and to efficiently and efficiently obtain data necessary for a scroll wrap processing apparatus. Another object of the present invention is to provide a scroll wrap processing method and a processing apparatus for efficiently obtaining a scroll wrap with good accuracy and, consequently, with good precision.

[0018]

SUMMARY OF THE INVENTION The present invention has been made to solve the above first to fourth problems. In order to achieve the first object, according to a first aspect of the present invention, a scroll wrap having a thickness defined by an involute curve is placed on the scroll wrap. Accuracy is measured by a combination of a rotary table having an angle detection function and a linear movement axis having a linear position detection function with a measuring element attached to a scroll wrap and detecting a displacement amount in at least one direction. A method of adjusting and processing a processing device based on a measurement result, the data for determining the accuracy of the outer line and the inner line of the scroll wrap, at least the angle of the rotary table and the position of the linear movement axis. After collecting as a group of measurement coordinate points having a plurality of measurement coordinate points determined by the above, the measurement coordinate points of the outer line and the inner line and the respective design values In order to minimize the sum of the deviations, coordinate transformation for parallel movement and coordinate transformation for rotational movement of both of the coordinate point sequence group of the outer line and the inner line in the same direction and in the same direction are performed. After obtaining the deviation between the measurement coordinate point of the extension and the design value, the average of the deviation is obtained as the average thickness, and the data relating to the tool diameter of the processing device, the tool position are set so as to eliminate the average thickness. At least one of the data relating to the deviation and the data relating to the tool trajectory is modified and machined.

That is, by performing coordinate conversion of the measured coordinate point sequence of the outer line and the inner line collectively, the thickness of the scroll wrap can be accurately determined by extracting not only the deviation relating to the shape but also the deviation relating to the dimensions. Thus, it is possible to adjust a processing device relating to tool wear.

In order to achieve the second object,
The configuration of the second invention according to the scroll wrap processing method of the present invention, in the configuration of the first invention, the coordinate conversion amount and the coordinate conversion direction for the parallel movement obtained by the coordinate conversion,
And the coordinate transformation amount and the coordinate transformation direction of the rotational movement are defined as the deviation of the base circle center coordinate and the deviation of the phase angle between the measured coordinate point of the scroll wrap and the design value, respectively. In order to eliminate the deviation of the phase angle, the machining is performed by correcting the data relating to the position control of the tool defined in the machining apparatus.

Further, in order to achieve the third object, a third aspect of the present invention relates to a method of processing a scroll wrap according to the present invention. When calculating the deviation from the value,
The design value is calculated by calculating from the involute curve equation by giving at least the base circle radius, the base circle center position, and the phase angle of the scroll wrap, and the design value for the measurement coordinate point is made to exist on the involute curve. In order to minimize the sum of the deviation between the coordinate point sequence group of the outer line and the inner line collected by the accuracy measurement and the design value, the two coordinate point sequence groups of the outer line and the inner line are translated by the same amount and in the same direction. In order to obtain the coordinate transformation amount to be rotated and the coordinate transformation amount to rotate and move, a sequence of measurement coordinate points within the range of the extension angle where both the outer line and the inner line exist are extracted and used. That is, the third invention is to reduce the occurrence of errors without using an approximate calculation by obtaining the design value from the design equation of the involute curve when obtaining the design value corresponding to the measurement coordinate point. .

Further, in order to achieve the fourth object, the structure of the fourth invention according to the method of processing a scroll wrap according to the present invention, wherein the distance from the rotation center provided on the rotary table in the above structure is reduced. The method includes a step of measuring a known reference gauge and grasping a center position of the rotary table with respect to a linear movement axis. That is, a gauge is attached near the rotation center of the rotary table, and the distance from the gauge and the rotation center is measured in advance by another device,
Since the center position can be ascertained by measuring the position of the gauge, even if the mechanism is displaced due to a change in environmental temperature or the like, if the gauge is measured, the rotational center position after the displacement can be ascertained. The first to fourth processing devices embody the first to fourth processing methods of the scroll wrap.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the embodiments, basic matters relating to the present invention will be described with reference to FIGS. FIG. 1 is an explanatory diagram showing a configuration of a unit for measuring accuracy using a rotary table in relation to processing of a scroll wrap, and FIG. 2 is an explanatory diagram showing an example of a design configuration of a scroll wrap. FIG. 3 is an explanatory view showing a method of measuring a scroll wrap using a rotary table.

As described above, the scroll compressor includes the orbiting scroll and the fixed scroll as parts having the scroll wrap. The main difference is the winding direction of the involute curve, and the same description will be given. Now, the scroll wrap of the orbiting scroll will be described. FIG. 1 is an explanatory diagram showing an outline of a configuration of an example of a unit for measuring accuracy in relation to processing of a scroll wrap. In FIG. 1, 2 is a rotary encoder and 4 is X
Axis scale, 6 is Y axis scale, 8 is Z axis scale, 9
a is a tracing stylus, 10 is a tracing stylus scale, 20 is an orbiting scroll, and 20a is a scroll wrap.

In the measuring unit having the configuration shown in FIG. 1, the center of the tracing stylus 9a is first rotated by using the Y-axis scale 6 in conjunction with the rotary encoder 2.
A base circle radius of the involute curve is offset from a center (not shown) in a direction parallel to the Y-axis scale 6.
Subsequently, the tracing stylus 9a contacts the scroll wrap 20a of the orbiting scroll 20, rotates the scroll wrap 20a, and follows the displacement caused by the rotation.
Move a. In this process, the angle is detected by the rotary encoder 2 and the X-axis scale 4 and the tracing stylus scale 1 are detected.
The position in the linear direction is detected by combining the data of 0. The coordinates obtained by the combination of the angle and the position are evaluated.

Here, a more detailed description will be given with reference to FIGS. FIG. 2 is an explanatory diagram showing a design example of the scroll wrap 20. In FIG. 2, 2
0a is a scroll wrap, S is an outer line of the scroll wrap, So is an outer line start point, Sn is a point on the outer line S, and Tn is a point S
n is the tangent at n, U is the inner line of the scroll wrap, Uo is the start point of the inner line, Un is a point on the inner line U, C is the base circle of the involute curve, r is the base circle radius, O is the base circle center, α is the phase angle, λn Is an extension angle, M is a reference groove for determining the XY directions in the processing machine, and H is a reference hole for processing the center position O in the processing machine.

In the example shown in FIG. 2, the coordinate system XY is based on the reference groove M and the reference hole H provided on the surface opposite to the scroll wrap 20a. The reference of the coordinate system XY may be a separately provided pin or the outer circumference of the orbiting scroll itself. In FIG. 2, the center O of the base circle C is arranged so as to coincide with the center of the coordinate system XY, but the position of the center O is not limited to this example, and may be at any position in the coordinate system. Absent. The outer line S starts from the intersection point So between the base circle C and the X axis, and OSo is the phase angle α and the extension angle λ.
It is a reference for n. The reference of the start position and the angle of the outside line may be other.

Here, the involute curve will be described using the outside line S. A normal line is drawn from the point Qn on the base circle having the extension angle λn to the base circle C, and the length of the line segment SnQn is equal to the arc S on the normal line.
A point Sn on the outer line S is determined so as to be equal to the length of oQn, and the locus of the point Sn when the expansion angle λn is changed is an involute curve. Further, the outer line S is displaced by the phase angle α so as to have a thickness, and a point U on the base circle is displaced.
The involute curve started from o is the extension U.
When the phase angle α is present as in the case of the extension line U, the length of the arc UoQn is equal to the length of the line segment UnQn. Also, the point Sn
Is the tangent Tn of the involute curve at
n.

FIG. 3 is an explanatory diagram showing a method of measuring a scroll wrap, which matches the design configuration described above, using a rotary table. In FIG. 3, the reference numerals are the same as those in FIG. 2, but the following reference numerals are added. That is, L is an extension of the line segment SnQn, Rn is an extension length which is the length of the line segment SnQn, 9a is a probe, Pn is a probe center, and rp is a probe radius.

In the example shown in FIG. 3, when the outer line S is rotated clockwise with reference to the center O of the base circle C, Sn on the line L passing through Qn and parallel to the X axis moves to the right. To go. Here, assuming that the length of the line segment SnQn is Rn, the involute curve has a property that the extension length Rn is equal to the product of the base circle radius r and the extension angle λn. Therefore, the base circle center O is made coincident with the center of the rotary table, and while the scroll wrap 20 is rotated, the expansion angle λn and the position of the point Sn are measured, and the length of the expansion length Rn is obtained. If they are compared, the deviation is obtained. Thereby, the accuracy can be measured. Where point S
The tangent line Tn at n is orthogonal to the straight line L, which means that the center of the tracing stylus 9a is also located on the straight line L. Therefore, the tracing stylus 9a may be configured to detect only in the direction of the straight line L. The above is the basic principle of measuring the scroll wrap using the rotary table and the linear axis moving mechanism.

Next, an embodiment of the present invention will be described with reference to FIGS. First, an embodiment of the first invention (claim 1) to the third invention (claim 3) will be described with reference to FIGS. FIG. 4 is an explanatory diagram showing an example of measurement coordinate points obtained by measurement according to the embodiment of the present invention, focusing on the vicinity of a base circle;
FIG. 3 is an explanatory diagram showing an example of measured coordinate points after coordinate conversion, focusing on the vicinity of a base circle.

In FIG. 4, S is the outer line design value of the scroll wrap, So is the outer line design start point, S1n is the outer line design coordinate point, U is the inner line design value of the scroll wrap, Uo is the inner line design start point, and U1i is the outer line design coordinate point. , C is the design base circle, r
Is the design base circle radius, O is the base circle design center, and α2 is the extension design phase angle.

S 'is a processed outer line, S'1n is a measured coordinate point of the outer line S', S'11 to S'15 are a sequence of measured coordinate points of the outer line, ΔS'1n is a deviation of S'1n, R '1n is the measured extension length of S'1n, which is the length of line segment Q'1nS'1n,
λ'1n is the measured spread angle of S'1n, Q'1n is the contact point of the tangent drawn from S'1n to the base circle C, α'11 is the processed external phase angle, and β'1n is the measurement of S'1n The error angle, U ′ is the processed extension, U′1i is the measurement coordinate point of the extension, U′11 to U′15 are the measurement coordinate point sequence of the extension, ΔU′1i is the deviation of U′1i, and R′1i is U '1i measured extension length, λ'1i is U'1
The measured divergence angle of i, Q′1i, is the contact point of the tangent drawn from U′1i to the base circle C.

Α′21 is the phase angle of the processed extension U ′, C ′
Is the base circle of the processed scroll wrap, O ′ is the center of the base circle of the processed scroll wrap, ΔO is the amount and direction of parallel translation by coordinate transformation, and Δα1 is the angle and direction of rotation by coordinate transformation. Although α1 corresponding to the design phase angle of the outer line is not shown, it is an example of zero, and the coordinates of the center of the design basic circle are (0, 0).

FIG. 4 shows that the center line O, the outer line design phase angle α1, and the inner line design phase angle α2 are manufactured to have deviations O ′, α′11, and α′21 due to the displacement of the apparatus. This is a measurement example of the scroll wrap 20a in which a undulating deviation relating to the shape is also added. The column of coordinates obtained by measuring the processed outer line S ′ is S′11 to S′1.
5 and S′1n, and the sequence of coordinates obtained by measuring the processed extension U ′ is U′11 to U′15 and U′1i.
It is.

Here, the coordinate conversion for minimizing the sum of the deviations ΔS′1n and ΔU′1i is performed by measuring the sequence of measured coordinate points S′1n of the outer line S ′ and the sequence of measured coordinate points U′1i of the inner line U ′. , A base circle C ′ having a radius r that best fits the outside line S ′ and the inside line U ′ is obtained, and the parallel movement of the base circle center O ′ to coincide with the base circle center O, α1, α′11, α2, The inclination angle Δα1 of the coordinate system X′Y ′ is obtained from the difference of α′21, and is equivalent to a coordinate transformation that rotates and moves in a direction to eliminate the inclination angle Δα1. Therefore, when the position of O ′ and the angle Δα1 are obtained, the coordinate conversion amount and the direction of the coordinate conversion can be grasped, but as an example, they are obtained as follows.

First, the measured R'1n and λ'1n
Therefore, the coordinate value (X′1n, Y′1n) of S′1n is given by Expression (1)
And (2), respectively, and similarly, the coordinate value (X ′) of U′1i is obtained from R′1i and λ′1i obtained by measurement.
1i, Y′1i) are obtained as in equations (3) and (4).

X′1n = rcosλ′1n + Rsinλ′1n (1) Y′1n = rsinλ′1n−Rcosλ′1n (2)

X′1i = rcosλ′1i + Rsinλ′1i (3) Y′1i = rsinλ′1i + Rcosλ′1i (4)

In general, the coordinates of the center position are (a, b)
And the involute curve whose phase angle is α can be expressed by the following equation.

X = r ｛cosλ + (λ−α) sinλ｝ + a (5) Y = r ｛sinλ− (λ−α) cosλ｝ + b (6) Equations (5) and (6) Is added to give equation [7].

(X + Y) = r {(cosλ + sinλ) + (λ−α) (sinλ−cosλ)} + (a + b) (7)

Here, in the equation (7), X and Y are X1n and Y1 obtained by the equations (1) and (2), respectively.
n ′, λ is λ′1n, and a, b and α are a ′
When replaced with 11n, b'11n, and α'11n, Equation (3) is equivalent to three unknowns a'11n, b'11n, and α'11.
It becomes an expression having n. In the case of using the equations (3) and (4) indicating the measurement coordinate points of the extension, the procedure is the same except that the subscripts of the symbols are changed. Thus, a set of (a′111, b′111, α′111) corresponding to a, b, and α is obtained by three measurement points, for example, S′11, S′12, and S′13.

Subsequently, when a similar operation is performed on the set of S'14, S'15, and S'16, (a'112, b'11
2, α'113) is obtained, and assuming that the final data of the outside line is S'1m, S'1m-2, S'1m-1, S'1m
The same operation is performed up to the set of (a′11k, b′11k,
α′11k). Similarly, for the measurement coordinate points of the extension, (a ′) is obtained from U′11, U′12, and U′13.
211, b′211 and α′211), and repeats to U′1h-2, U′1h−1, and U′1h including the final measurement coordinate point of the extension, and (a′21j, b′21j, α ′) 21j). Here, the number of measurement coordinate points is adjusted to a number that is a multiple of three.

Also, the method of creating the set of measurement points is not divided every three points, but is the smallest, such as S'12, S'13, S'14, following S'11, S'12, S'13. A method of increasing the rank by one may be used, or a method of thinning out the middle without using all the data obtained by the measurement to shorten the calculation time may be used. The first digit of the subscripts added to a ', b', α 'is a serial number, the second digit is the number of coordinate conversions, and 3
The first digit indicates that 1 is a value obtained from the outside measurement coordinates, and 2 indicates that it is a value obtained from the inside measurement coordinates.

The X coordinates a'111 to a'11k, a'211 to a'21j, and the Y coordinates b'111 to b'11k, b of the centers of a plurality of base circles obtained in the above process are shown. '211 to b'21j, and the phase angles α'111 to α'11k and α'211 to α'
21j are obtained, the respective average values are obtained, and the difference from the design value is obtained as follows. In Equations (8) to (10), the X coordinate of the center of the base circle of the design value is a, the Y coordinate is b, the phase angle of the outer line is α1, and the phase angle of the inner line is α2. In the example of FIG. 4, a and b are zero.

[0043]

(Equation 5) The coordinate of the measured coordinate point is converted so as to eliminate the difference between the measured coordinate and the design value shown in Expressions (8) to (10). That is, each measurement coordinate point is moved by Δa1 in the X direction, by Δb1 in the Y direction, and further rotated by Δα1.
One coordinate conversion is completed by the above operation.

Here, the measured coordinate points S′1n and U′1i are not yet in the most suitable positional relationship with the design values S1n and U1i. This is because the normal spread angle corresponding to S′1n is λ ″ 1n of the imaginary base circle C ′, but cannot be directly obtained by measurement, and λ′1n obtained by measurement.
This is because it is adopted. Here, an error β′1n exists. Therefore, from the coordinate points after the coordinate conversion, the expansion angle is calculated again according to the following equations (11) and (12), and the calculation regarding the coordinate conversion from the equations (8) to (10) is performed again. In Expressions (11) and (12), ω is a numerical value selected according to Table 1 depending on the quadrant where the coordinate point exists.

[0045]

(Equation 6) Where ζ is the number of turns. The second digit of the subscript represents the number of coordinate conversions.

[Table 1]

Here, until the coordinate conversion amount is sufficiently smaller than the judgment accuracy and becomes equal to or less than the expected value, the extension angle is obtained again by the above-described equations (11) and (12), and the equation (11) is obtained. The coordinate transformation of equation (10) is repeated from 8). here,
Let w be the number of times coordinate transformation is performed, and Δa be the amount of coordinate transformation
Assuming that w, Δbw, and Δαw, the total obtained by performing the coordinate conversion up to the last round is as follows.

[0047]

(Equation 7) FIG. 5 schematically shows the measured coordinate points obtained after the series of coordinate transformations described above around the center of the base circle.
The applied symbols are the same as those in FIG. 4, but some of the suffixes are omitted.

In the state shown in FIG. 5, the sum of the deviations ΔSn ′ and ΔUi ′ between the measured coordinate points and the design values is minimal, and the measured coordinate points Sn ′ and Ui ′ of the outer line and the inner line are translated in the same direction. Have been rotated by the same angle, the relative positions of the two have not changed, and the deviations ΔSn ′ and ΔUi ′ are thickness deviations including not only the shape deviation but also the thickness deviation.

As the wear of a tool (not shown) used for machining progresses, the diameter of the tool decreases, and as a result, the scroll wrap 20a becomes thicker. Can be caught. The average ΔT of the thickness deviation is obtained as follows, and is defined as the average thickness.

(Equation 8)

The data relating to the tool diameter of the machining apparatus, the data relating to the tool offset, or the data relating to the tool trajectory are corrected in such a direction as to eliminate the average thickness ΔT obtained by the equations (16) to (18). . In the example of correcting the data relating to the tool diameter, the average thickness is subtracted from the data of the tool diameter used when processing the measured scroll wrap 20a. By doing so, in the subsequent processing, the tool moves on the trajectory approaching the scroll wrap by the average thickness described above, and as a result, a scroll wrap with good accuracy and with the thickness deviation eliminated is obtained. be able to. Further, if ΔS ″ n and ΔU ″ n shown in FIG. 5 are obtained in the same manner as in the equations (16) to (18), only the shape deviation can be extracted.

Further, from the above-mentioned equations (13) to (15)
.DELTA.A, .DELTA.B, and .DELTA..PHI.
These are the deviation in the axial direction, the deviation in the Y direction, and the deviation in the phase angle. Therefore, these ΔA, ΔB, ΔΦ are the X axis of the processing device, Y
Indicates the amount and direction of adjusting the axis and rotation angle. In this way, since a set of data for adjusting the processing device can be obtained, the data constituting the coordinates related to the processing of the scroll wrap of the processing device with a tendency to eliminate ΔA, ΔB, ΔΦ, For example, the data of the position and angle of the work coordinate system with respect to the machine origin coordinates are corrected, and the subsequent processing is performed. In this way, a scroll wrap with good position accuracy can be obtained. In the above-described series of processes, the calculation is performed using the design involute curve itself, and the operation of fitting an approximate curve is not performed, so that accurate evaluation can be performed.

Next, an embodiment according to the third invention (claim 4) will be described with reference to FIG. FIG. 6 is an explanatory view showing an example of an orbiting scroll according to another embodiment of the present invention, in which there is an area requiring high accuracy only for an extension. In FIG. 6, reference numeral 20 denotes an orbiting scroll, reference numeral 20a denotes a scroll wrap, reference numeral 20b denotes an outer line, reference numeral 20c denotes an inner line, and reference numeral E denotes an involute curve extension angle area.

In the embodiment shown in FIG. 6, there is no partner to be combined with the fixed scroll on the outside line 20b in the area designated by E. Therefore, the outer line 20b of the region E is not defined by a continuous involute curve other than the portion E, and the outer wrap 20a is shifted so as to make the scroll wrap 20a thinner. In this example, the area E of the outer line 20b does not require high accuracy and is excluded from the range of the accuracy measurement. Therefore, in the E region, at the same extension angle, the measurement coordinates of the inside line 20c exist, but the measurement coordinates of the outside line 20b do not exist.

In such an example, measurement data excluding the area E is used in the coordinate system conversion performed using the above-described equations (7) to (15). On the other hand, in the operation for calculating the thickness deviation and the average thickness shown in Expressions (16) to (18) performed after the repeated coordinate conversion, the data of the outer line 20b of the area E is used. In other words, the measurement coordinate points used for the coordinate transformation use the range of the extension angle where both the outer line 20b and the inner line 20c exist, and the thickness deviation is determined for all the measurement coordinate points. To evaluate.

By the above operation, in this example, it is possible to prevent the coordinate transformation that causes the measured coordinate point to be too close to the design value with the larger measured coordinate, such as the extension, and to arrange the coordinates more appropriately. . On the other hand, the evaluation of the thickness deviation is not an operation of transforming the coordinates, but merely a calculation of the deviation from the design value. Therefore, all the measured coordinates may be used. The present invention
In particular, when a scroll wrap having a large thickness deviation from a design value is measured, it is effective in preventing error expansion.

Next, an embodiment according to the fourth invention (claim 5) will be described with reference to FIG. FIG. 7 is an explanatory diagram showing the configuration of the measurement unit according to the embodiment of the present invention. In FIG. 7, 1 is a rotary table, 2 is a rotary encoder, 3 is an X axis, 4 is an X axis scale, 5 is a Y axis, 6
Is a Y-axis scale, 7 is a Z-axis, 8 is a Z-axis scale, 9 is a measuring head, 9a is a tracing stylus, 10 is a tracing stylus scale, 11
Is a scale position detecting device, 12 is an operation control device, 13 is a position data memory, 13a is an outside line data area, 13b is an extension data area, 14 is a design parameter memory, 15 is an arithmetic unit, 16 is a display, and 17 is a printer. .

In the configuration shown in FIG. 7, a cylindrical gauge A is mounted on the turntable 1. The gauge A is larger than the outer shape of the orbiting scroll 20 to be measured in this example, and the measuring element 9a of the measuring head 9 can measure the position of the gauge A even when the orbiting scroll 20 is mounted on the rotary table 1. The radius of the gauge A is measured before the gauge A is mounted on the turntable 1. With such a configuration,
Immediately before starting the measurement of the orbiting scroll 20, the gauge A
Is measured by the tracing stylus 9a. When the radius value of the gauge A already measured is added to the position of the side surface of the gauge A obtained as a result, the X axis 3 of the rotation center of the turntable 1 is obtained.
Position with respect to.

In this measurement, the rotary table 1 is rotated, data for one rotation is collected, the eccentric component existing at the center of the gauge A and the center of the rotary table 1 is removed, and then the radius of the gauge A is obtained. Is preferred. Alternatively, the radius may be grasped at a specific angle of the gauge A, and the position of the side surface may be measured at this angle. In the above description, the gauge A has been described as a cylindrical shape, but a block-shaped gauge is provided at a measurable position of the rotary table 1 in a direction of a specific angle by grasping the distance from the rotation center of the rotary table 1. You may.

As described above, by measuring the center of the rotary table 1 before the measurement of the orbiting scroll 20 is started, the X axis 3 and the rotary table 1 generated when the unit base expands and contracts due to environmental temperature fluctuation or the like. Can be eliminated, and high-precision measurement with a small phase angle measurement error can be performed. This is particularly effective when the base circle radius is as small as about several millimeters and the X axis 3 is as long as about several hundred millimeters.

Next, an embodiment of the scroll wrap processing apparatus of the present invention will be described with reference to FIG. 7 used in the above description. In the measuring unit shown in FIG. 7, the rotary table 1 on which the orbiting scroll 20 can be placed is provided with a rotary encoder 2 for detecting an angle, and is capable of rotating while detecting the angle. An X-axis 3 capable of linearly moving in a direction perpendicular to the axis is provided, and an X-axis scale 4 for detecting a position of the X-axis in the moving direction is provided. The Y-axis 5 is disposed so as to be at a right angle, and a Y-axis scale 6 for detecting the position of the Y-axis in the moving direction is provided.

Further, a Z-axis 7 is arranged so as to be perpendicular to the moving direction of the X-axis 3 and parallel to the rotation axis of the rotary table mechanism 1, and to detect the position of the Z-axis 7 in the moving direction. A scale 8 is provided, and a measuring head 9 is mounted on the tip of the Z-axis 7. The measuring head 9 has a tracing stylus 9 a which comes into contact with the scroll wrap 20 and moves in parallel with the moving direction of the X-axis 3. A measuring element scale 10 for detecting the position of the element 9a in the moving direction is provided. Here, the tracing stylus 9a is configured to move in one direction, but may be configured to move in two or more orthogonal directions and detect each position. The rotary table 1, the X-axis 3, the Y-axis 5, and the Z-axis 7 are driven by a servo motor (not shown) and can move according to a predetermined program.

In the above configuration, first, the Y-axis 5 is driven by the operation control device 12, and the center of the turntable 1 is offset from the center of the tracing stylus 9a by the base circle radius of the involute curve according to the data of the Y-axis scale 6. . Then X
By driving the shaft 3, the Z-axis 7, and the rotary table 1, the tracing stylus 9a of the measuring head 9 is moved to the measurement start point, and the tracing stylus 9a is brought into contact with the scroll wrap 20a. Thereafter, while rotating the rotary table 1, the measuring head 9 attached to the Z-axis 7 is driven by the X-axis 3 so that the tracing stylus 9a follows the scroll wrap. The control of the measurement order
0b, the extension 20c, or the center or the outer periphery. In addition, the measurement order may be such that the outer line 20b and the inner line 20c both start the measurement from the outer periphery, or may be the control from the outer periphery toward the center and continuously return from the center to the outer periphery. The operation control device 12 has a function of performing the above operation.

Here, the tracing stylus 9a is moved to the scroll wrap 2
In the process of following 0, the scale position detecting device 11 has a function of counting the rotary encoder 2, the X-axis scale 4, and the tracing stylus scale 10. The external position data area 13a or the extension data area 13b of the position data memory 13 has a function of counting. And a function of storing position detection device data corresponding to the measurement portion. On the other hand, the design parameter memory 14 stores at least a basic circle center coordinate, a basic circle radius, a phase angle, an outer line expansion angle range, and an inner line expansion angle range as design data of the outer line 20b and the inner line 20c.

At the stage when the collection of the measurement coordinate points is completed, the arithmetic unit 15 uses the measurement coordinates of the position data memory 13 and the data of the design value parameter memory 14 to express the equations (1) to (15). It has the function of performing the calculation of the method. The amount and direction of translation of the coordinate system obtained by this function,
The display 16 has a function of displaying the amount and direction of the rotational movement, and the printer 17 has a function of printing if necessary. In addition, the arithmetic unit 15 also has a function of performing the operations of the methods shown in Expressions (16) to (18),
The result can be displayed on the display 16 and can be printed by the printer 17 if necessary. In the above description, the result of the operation is artificially viewed and the data of the processing device is corrected.
The configuration may be such that the calculation result is transferred to the processing device and the data of the processing device is automatically changed.

In the configuration shown in FIG. 7, when calculating the coordinate transformation amount, the area of the expansion angle where only one of the outer line 20b and the inner line 20c exists as shown in FIG. It has the function of judging from the stored spread angle data and excluding it from the data for obtaining the coordinate conversion amount. By the way, the rotary table 1 employs a structure equipped with a cylindrical gauge A having a known radius. By measuring the gauge A immediately before or immediately after the scroll wrap 20 is measured, the rotation center of the rotary table 1 with respect to the X-axis scale 4 can be grasped, and accurate measurement can be performed even if the measurement unit causes thermal displacement or the like. It becomes a possible configuration.

[0066]

As described above, according to the first invention, the first problem which has existed conventionally can be solved.
By obtaining the coordinate transformation amount of the parallel movement and the rotational movement of the set, and using this as a deviation from the reference, it is possible to easily and accurately obtain data to adjust the processing device from the measurement data,
As a result, it is possible to provide a scroll wrap processing method and a scroll wrap processing apparatus capable of efficiently obtaining a high-accuracy scroll wrap.

Further, according to the second invention, the second problem which has existed conventionally can be solved, and the deviation between the design value and the measured value is obtained after performing coordinate transformation using both the data of the outside line and the inside line. And a processing apparatus for a scroll wrap capable of easily and accurately obtaining thickness adjustment data which can be obtained by reducing a tool diameter due to tool wear and thereby obtaining a deviation including a thickness. Can be provided.

Further, according to the third invention, the third problem which has existed conventionally can be solved, and the evaluation accuracy of the measured data can be improved more than before by obtaining the design value from the design equation of the involute curve. Thus, it is possible to provide a scroll wrap processing method and a processing apparatus capable of improving the processing accuracy.

Further, according to the fourth invention, the fourth problem which has existed conventionally can be solved, the influence of the thermal displacement of the measuring unit can be excluded, and high accuracy can be obtained even in a poor processing site environment. It is possible to provide a method and an apparatus for processing a scroll wrap capable of performing measurement.

In summary, according to the present invention, the shape, position, and thickness of the scroll wrap are evaluated by the measurement unit using the rotary table, and the data necessary for the scroll wrap processing device can be accurately and efficiently obtained. Thus, it is possible to provide a scroll wrap processing method and a processing apparatus for efficiently obtaining a scroll wrap with good precision and, consequently, good precision.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a unit for measuring accuracy using a rotary table in relation to processing of a scroll wrap.

FIG. 2 is an explanatory diagram showing an example of a design configuration of a scroll wrap.

FIG. 3 is an explanatory diagram showing a method of measuring a scroll wrap using a rotary table.

FIG. 4 is an explanatory diagram showing an example of measurement coordinate points obtained by measurement according to the embodiment of the present invention, focusing on the vicinity of a base circle;

FIG. 5 is an explanatory diagram showing an example of measurement coordinate points after coordinate conversion, focusing on the vicinity of a base circle.

FIG. 6 is an explanatory diagram showing an example of an orbiting scroll according to another embodiment of the present invention, in which there is a region requiring high accuracy only for an extension.

FIG. 7 is an explanatory diagram showing a configuration of a measurement unit according to the embodiment of the present invention.

FIG. 8 is a perspective view showing the appearance of a scroll wrap.

[Explanation of symbols]

1 ... rotary table, 2 ... rotary encoder, 3 ... X
Axis, 4 ... X axis scale, 5 ... Y axis, 6 ... Y axis scale,
7 ... Z axis, 8 ... Z axis scale, 9 ... Measurement head, 9a ...
Measuring element, 10: measuring element scale, 11: scale position detecting device, 12: operation control device, 13: position data memory, 13a: external line data area, 13b: internal line data area, 14: design parameter memory, 15: arithmetic unit .

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuo Abe 800, Tomita, Ohira-cho, Shimotsuga-gun, Tochigi Prefecture Inside the Cooling & Cooling Business Dept., Hitachi, Ltd. Hitachi, Ltd.Cooling Division (72) Inventor Tatsuo Horie 800, Tomita, Ohira, Shimotsuga-gun, Tochigi Pref.

Claims (10)

[Claims] 1. A rotary table having an angle detecting function for placing a scroll wrap having a thickness defined by an involute curve on the scroll wrap, and detecting a displacement amount in at least one direction by abutting the scroll wrap. A method for performing accuracy measurement in combination with a linear movement axis having a linear position detection function with a tracing stylus attached thereto, and adjusting and processing a processing device based on a result of the accuracy measurement, wherein the outer line of the scroll wrap is provided. And collecting data for determining the accuracy of the extension as a group of measurement coordinate points having a plurality of measurement coordinate points determined by at least the angle of the rotary table and the position of the linear movement axis. In order to minimize the sum of deviations between the coordinate points and the respective design values, both the outer line and the inner line coordinate point sequence group have the same amount and After performing a coordinate transformation for performing parallel translation in one direction and a coordinate transformation for performing rotational movement, subsequently, a deviation between the measured coordinate points of the outer line and the inner line and the design value is obtained, and an average of the deviation is obtained to obtain an average thickness. The method is characterized in that at least one of data relating to a tool diameter, data relating to a tool position deviation, and data relating to a tool trajectory of the processing device is corrected and processed so as to eliminate the average thickness. Processing method of scroll wrap. 2. The scroll wrap machining method according to claim 1, wherein the coordinate transformation amount and the coordinate transformation direction for the parallel movement and the coordinate transformation amount and the coordinate transformation direction for the rotational movement determined by the coordinate transformation are respectively measured. The deviation of the base circle center coordinates and the deviation of the phase angle between the measurement coordinate point of the lap and the design value are set as the deviation of the base circle center coordinates and the phase angle deviation. A scroll lap machining method, wherein machining is performed by correcting data relating to tool position control. 3. The scroll wrap machining method according to claim 1, wherein the design value is at least the value of the scroll wrap when calculating a deviation between each measurement coordinate point obtained by the measurement and the design value. A scroll wrap processing method characterized in that a base circle radius, a base circle center position, and a phase angle are given to calculate by an involute curve equation, and a design value for the measurement coordinate point is present on the involute curve. 4. The scroll wrap processing method according to claim 1, wherein a total sum of deviations between a coordinate point sequence group of the outer line and the inner line collected by the accuracy measurement and a design value is minimized. In determining the coordinate transformation amount for translating the coordinate line sequence group of the outer line and the inner line in the same amount and in the same direction and the coordinate transformation amount for the rotational movement, the range of the extension angle in which both the outer line and the inner line exist. A method of processing a scroll wrap, wherein a sequence of measurement coordinate points is extracted and used. 5. The method for processing a scroll wrap according to claim 1, wherein a reference gauge provided on the rotary table and having a known distance from a rotation center is measured, and the center of the rotation table with respect to a linear movement axis is measured. A method of processing a scroll wrap, comprising a step of grasping a position. 6. A rotary table having an angle detecting function for placing a scroll wrap having a thickness defined by an involute curve on the scroll wrap, and detecting a displacement amount in at least one direction by abutting the scroll wrap. A scroll wrap processing device that performs accuracy measurement in combination with a linear movement axis having a linear position detection function with a tracing stylus attached thereto, and adjusts processing data based on a result of the accuracy measurement. Means for collecting data for determining the accuracy of the outside line and the inside line as a group of measurement coordinate points having a plurality of measurement coordinate points determined by at least the angle of the rotary table and the position of the linear movement axis; and the outside line and the inside line Coordinate point sequence group of the outer line and the inner line so that the sum of the deviations between the measured coordinate points and the respective design values is minimized. Means for performing coordinate transformation for parallel and rotational movement of the two in the same direction and in the same direction; and determining a deviation between the measured coordinate points of the outer line and the inner line and the design value, and calculating an average of the deviation to obtain an average thickness. Means for correcting at least one of data relating to a tool diameter of the processing apparatus, data relating to a tool position deviation, and data relating to a tool path so as to eliminate the average thickness. A scroll wrap processing device characterized by the following. 7. The scroll wrap processing apparatus according to claim 6, wherein the coordinate transformation amount and the coordinate transformation direction for the parallel movement and the coordinate transformation amount and the coordinate transformation direction for the rotational movement determined by the coordinate transformation are respectively measured. The deviation of the base circle center coordinates and the deviation of the phase angle between the measurement coordinate point of the lap and the design value are set as the deviation of the base circle center coordinates and the phase angle deviation. A scroll wrap processing apparatus, comprising: means for correcting and processing data relating to tool position control. 8. The scroll wrap processing apparatus according to claim 6, wherein the deviation between each measured coordinate point obtained by the measurement and the design value is determined at least by the design value of the scroll wrap. Scroll lap processing characterized by having means for calculating a calculation value from an involute curve equation by giving a base circle radius, a base circle center position, and a phase angle, and causing a design value for the measurement coordinate point to be present on the involute curve. apparatus. 9. The scroll wrap processing apparatus according to claim 6, wherein a sum of deviations between a set of coordinate points of an outer line and an inner line collected by accuracy measurement and a design value is minimized. In determining the coordinate transformation amount for translating the coordinate line sequence group of the outer line and the inner line in the same amount and in the same direction and the coordinate transformation amount for the rotational movement, the range of the extension angle in which both the outer line and the inner line exist. A means for extracting and using a group of coordinate points in the scroll wrap. 10. The scroll lap processing device according to claim 6, wherein a reference gauge whose distance from the rotation center is known is provided on the rotary table mechanism. .