JPH0142002Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is based on the vertical position of the deflected center curve of a long cylindrical workpiece that is supported horizontally at both ends and stands still while being bent by its own weight. This invention relates to an automatic measuring device that calculates the radius of the measured object at that position by calculating it from the radius measurement values of two opposing points on the vertical diameter of the object to be measured.

The purpose of this invention is to machine a cylindrical beam workpiece, such as a shaft, with a machine tool such as a lathe, and then attach both ends of the workpiece to the machine tool horizontally and rotatably. By measuring the outer diameter of this workpiece in the vertical direction, it is possible to determine the center line of the machine tool main axis of the workpiece itself, which is bent due to its own weight with both ends supported. A novel technology that calculates the amount and direction of deviation from the center line of rotation, that is, the reference line, and determines the position of the center line of the object being measured, which is curved downward with support at both ends. An object of the present invention is to provide a detection device.

Another purpose of this invention is to use the measured and calculated amount of deviation to set the tool position correction function or coordinate system of the numerical control device, for example, in a machine tool such as a numerically controlled lathe that machining the workpiece. It is equipped with an interface with a numerical control device so that input to the function automatically aligns the cutting edge position of the cutting tool with the bent center line of the workpiece and performs cutting feed by numerical control. It is an object of the present invention to provide a detection device that has the following characteristics.

First, the measurement principle of this invention will be explained with reference to FIG.

With both ends of a long cylindrical workpiece W mounted horizontally and rotatably around a rotation center line C, the outer diameter of the workpiece W is determined using the rotation center line C as a reference position for measurement. One or two detectors S are used, a vertical line at an arbitrary position passing through the rotation center line C is defined as a measurement axis V, and a
Calculate the radius deviation value (D + D') from the two radius measurement values D and D' measured by the detector at arbitrary required positions A and B that are 180 degrees opposite each other, and further calculate the calculated deviation amount. By dividing it into two equal parts, the amount and direction of deviation between the rotation center line C on the measurement axis V and the center line C' of the cylindrical object W to be measured are determined.

That is, now, if we take the rotation center line C as the measurement reference O, and add positive and negative signs to the directions shown in the figure, the radius measurement value at A: D (amount of +), the radius measurement value at B:
D' (-amount), radius deviation value: Δ, deviation amount between rotation center line C and cylindrical object center line C': δ, radius deviation value Δ=D+D'...(1) Rotation Amount of deviation between the center line C and the center line C' of the cylindrical object to be measured δ=Δ/2=D+D'/2...(2) In equation (2), if D=D', δ=0, The center line C' of the cylindrical object to be measured coincides with the rotation center line C.

When D>D', δ>0, and the center line C' of the cylindrical object is located in the + direction from the rotation center line C by δ.

When D<D', δ<0, and the center line C' of the cylindrical object is located in one direction by δ from the rotation center line C.

The cylindrical object to be measured W is supported at both ends, stands still horizontally, and is bent downward due to its own weight.
In other words, the amount of deviation δ from the rotation center line C connecting the support centers P ₁ and P ₂ at both ends varies depending on the shape of the object W and the distance L from the support points P ₁ and P ₂ at both ends. The value will be different.

Therefore, if necessary, move the detector S in the direction of the rotation center line C to measure any measurement axes V ₁ , V ₂ , ...V _o
By setting the position and performing the measurements and calculations as described above, it is possible to determine the amount of deviation δ at any set point in the axial direction.

Hereinafter, embodiments of the structure of this invention will be explained with reference to block diagrams shown in FIGS. 2 to 6. first second
The figure shows a measuring device consisting of one detector S and a measurement control device 10.

The detector S detects the maximum radius value of the cylindrical object W.
The detector S has a measurement range greater than or equal to Dmax, and the probe 1 of the detector S is always pushed out from the detector body 2 toward the outer periphery of the object W by a spring (not shown).

Place the probe 1 at a point A on the outer circumference of the cylindrical object W.
When the tip of the measuring point 1 is applied, the radius D of the measuring point is
The spring is pushed in, and the probe 1 comes to enter the detector main body 2.

The fixed part main body 2 has a built-in detection element that converts the amount of displacement of the probe 1 into an electrical quantity such as voltage and outputs it, and the relative displacement amount, that is, the radius D.
It generates an amount of electricity E corresponding to and outputs it.

In this case, the detection element may be of either an analog type or a digital type, but the following description will refer to the digital type.

On the other hand, the measurement control device 10 consists of a bidirectional counter with a built-in calculator, and the counter 11 counts the output digital amount E from the detector S.

The measured value counted by the counter 11 is stored in the memory 12.
Or stored in 13.

In the figure, the memory 12 is used for measurements from the + direction, and the detector S is flipped around the rotation center line C to measure from one direction 180 degrees opposite to it (indicated by the dotted line in the figure). In this case, directional switch 1
The memory 13 is used through 4 and 15.

The calculator 16 compares and calculates the contents of the memory 12 and the contents of the memory 13, and outputs a digital amount E〓 corresponding to the deviation amount δ to the outside.

Furthermore, a counter 11 and a memory 12 are connected to the measurement control device 10 manually or automatically from the outside.
Measurement control is performed by inputting a reset command 17 for resetting the contents of 13, a direction switching command 18 for switching between + and - of the measured value depending on the measurement direction, and a comparison/calculation/output command 19 for causing the calculator 16 to perform calculations. The device 10 is controlled based on these instructions.

Figure 3 shows another embodiment of this invention.
Detectors S ₁ and S ₂ are located at 180° on the vertical measurement axis V.
The measurement apparatus is constructed by arranging the measurement apparatuses at opposite positions, and simultaneously measures the radii D and D' on the diameter of the cylindrical object W in the vertical direction.

The detector S ₁ measures a positive measured radius value D, and the detector S ₂ measures a single measured radius value D', and their configuration is the same as that of the detector S described in FIG. 2.

The measurement control device 20 consists of two bidirectional counters and a calculator.

The counter 21 counts the + measured digital amount E ₁ from the detector S ₁ , and the counter 22 counts the positive measured digital amount E 1 from the detector S _1.
Count the measured digital quantity E ₂ of - from .

Two count values E ₁ and E ₂ of both counters 21 and 22
is simultaneously input to the calculator 26, compared and calculated, and sent to the outside as a digital quantity Eδ corresponding to the deviation amount δ.
is output.

Further, the measurement control device 20 receives from the outside a reset command 27 for manually or automatically resetting the counters 21 and 22, a comparison/calculation/output command 29 for causing the calculator to perform calculations, etc., and the measurement control device 20 receives these commands. It is controlled based on the instructions of

Compared to the method shown in FIG. 2, this method has the advantage that the measuring time can be shortened because two detectors S are used in the measuring device and the measurements are performed simultaneously.

Furthermore, since there is no need to store the measured values using a memory, the measurement control device 20 becomes simpler.

FIG. 4 shows still another embodiment of this invention, in which a single detector S ₃ and a measurement control device 10 are used as measuring devices.
It is composed of.

The detector _S3 is composed of an electric or magnetic linear digital scale 4 disposed parallel to the measurement axis V, and a detection head 3 that is movable vertically on the scale 4. When the relative position between the detection head 3 and the detection head 3 changes, a pulse train is generated as an amount of electricity corresponding to the relative position change.

The detection head 3 is further equipped with a protruding scriber 5, which is clamped to the detection head 3 with a stop screw 7.

The measuring direction of the scriber 5 on the measuring axis V can be changed from + to - as shown in the figure by loosening the stop screw 7, rotating the measuring surface 6 by 180 degrees and reinstalling it facing upward.

In the figure, in the case of measurement from the + direction, the measurement surface 6 of the scriber 5 is directed downward, and is applied to the upper outer edge A of the cylindrical object W to be measured to measure the upper radius value D.

In the case of measurement from one direction, the measurement surface 6 of the scriber 5 is rotated halfway and applied to the outer circumferential lower edge B of the cylindrical object W to be measured, and the lower radius value D' is measured.

On the other hand, the measurement control device 10 has exactly the same configuration and function as the measurement control device 10 shown in FIG.

This detector _S3 makes it possible to set the radius value of the object to be measured W having a larger diameter than in the methods shown in FIGS. 2 and 3.

FIG. 5 shows still another embodiment of this invention, in which the two detectors S ₃ and S ₄ constituting the measuring device are identical and located parallel to the vertical measuring axis V. They are each movably attached to a linear digital scale 4 and have the same configuration as the detector _S3 in FIG. 4.

The detector S ₃ measures the positive measured radius value D, and the detector S ₄ measures the single measured radius value D' almost simultaneously.

In the figure, when measuring from the + direction, the detector
The measurement surface 6 of the scriber 5 of _S3 is applied to the upper outer edge A of the cylindrical object W to be measured, and the upper radius value D thereof is measured.

In the case of measurement from one direction, the measurement surface 6 of the scriber 5 of the detector S ₄ is applied to the lower outer edge B of the cylindrical object W to measure the lower radius value D'.

This measurement control device 20 has exactly the same configuration and functions as the measurement control device 20 shown in FIG.

This method has an advantage over the method shown in FIG. 3 in that it can measure even when the diameter of the object W to be measured is large.

FIG. 6 shows still another embodiment of this invention, in which the position detection device has two detectors S ₁ and S ₂ with both probes 1 facing each other on the vertical measurement axis V. It is composed of a measuring device attached to a U-shaped bracket 30 and a measurement control device 20.

Both the detector S ₁ and the detector S ₂ have the same configuration as the detector S described in FIG. 2.

In addition, counters 21 and 22 in the measurement control device 20
The memories 23, 24 and calculator 26 also have the same functions as those in FIG.

In the measurement, first, as an initial operation, the bracket 30 of the measuring device is positioned in the X direction so that the vertical line connecting both measuring stylus 1 passes through the reference point O on the rotation center line C.

In this state, between the upper and lower two detectors S ₁ and S ₂ , with the reference point O as the center, a reference diameter of 2 is placed between the upper and lower detectors with the same radius.
D ₀ Press measuring gauge G.

As a result, both the probes 1 of the two upper and lower detectors S ₁ and S ₂ undergo a certain displacement. In this state, the reset command 27 is sent to the two counters 2 of the measurement control device 20.
1 and 22, and set both counters to zero.

The initial operation is then completed by removing the measuring gauge G.

Next, a measurement operation for a cylindrical object W having a target diameter value of _2D1 will be explained.

The diameter value 2D ₀ of the measuring gauge G used earlier,
The radius difference d from the target diameter value 2D ₁ of the cylindrical object W is d = 1/2 (2D ₀ - 2D ₁ ) = D _{0 -} D ₁ ...(3) The bracket 30 can be obtained using equation (3). The probe 1 of the detector S ₁ is first moved downward by a radius difference d, and the probe 1 of the detector S 1 is pressed against the upper edge A of the outer periphery of the object W to be measured, which is bent.

At this time, if the radius value of the object W to be measured is the same with respect to the target radius value 2D ₁ , the detector S ₁ will not generate a displacement signal, and only if there is a deviation, a displacement signal corresponding to the difference amount will be generated. E ₁ occurs.

This displacement signal _E1 is counted by a counter 21,
It is stored in the memory 23. Let this stored radius deviation value be δ ₁ .

Similar measurements are also performed on the lower outer edge B of the object W to be measured. The displacement signal E ₂ obtained thereby is counted by the counter 22 and stored in the memory 24 as the radius deviation value δ ₂
is stored as.

Based on the upper radius deviation value δ ₁ and lower radius deviation value δ ₂ obtained by these measurements, the calculator 26 is operated by the comparison/calculation command 29 to perform calculation 1/2 (δ ₁ +δ ₂ )=δ, The cylindrical object to be measured W
The deviation amount δ from the rotation center line C of the center line C' is output as E〓, which is input to the numerical control device of the machine tool (not shown) via an interface (not shown), and the tool is corrected as necessary. Activate the function or coordinate system setting function to correct the cutting edge position of the cutting tool used in the next process or change the coordinate system settings, or display the actual cut object on a separately provided display device (not shown). The processed diameter or the amount of deflection thereof can be displayed.

This method has the advantage that the measurement range of the detector S is smaller than the methods shown in FIGS. 2 and 3, and it can be used to measure objects W having a large diameter.

The measuring device of the known automatic measurement and correction device conventionally used in numerically controlled lathes etc.
Since the radius or diameter of the cylindrical workpiece is measured on the XZ plane, that is, on the horizontal plane passing through the center line of rotation, by using movement in both Z-axis directions, it is especially suitable for large, long and heavy workpieces. However, with this device configured as described above, by measuring the outer diameter of the cylindrical object on a vertical line passing through the rotation center line, it is possible to measure not only the actual diameter but also the outer diameter of the cylindrical object. The amount of deflection can be measured and output at any position in the direction of the center line.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the measurement principle of this invention, and FIGS. 2 to 6 are block diagrams showing different embodiments of the measuring device and measurement control device of this invention. DESCRIPTION OF SYMBOLS 1... Measuring point, 2... Detector body, 3... Detection head, 4... Linear scale, 5... Scriber, 10, 20... Measurement control device, W... Cylindrical object to be measured, D ...Radius of the object to be measured, C...Rotation center line, C'...Center line of the object to be measured, V...Measurement axis, S...Detector.

Claims (1)

[Claims for Utility Model Registration] (1) In a device for detecting the amount of deflection of the center line of a measured object of a cylindrical beam whose both ends are rotatably supported, the cylindrical beam is a measuring device for measuring an upper radius value D and a lower radius value D' from the rotation center line of the object to be measured; and a measuring device for measuring an upper radius value D and a lower radius value D' measured by the measuring device. Operation 1/2 (D
+D') = δ and a measurement control device that outputs the deviation amount δ of the center line of the object to be measured of the cylindrical beam from the rotation center line. (2) The measuring device is aligned vertically through the rotation center line.
A cylindrical beam deflection detection device according to claim (1) of the utility model registration claim, which includes a pair of detectors arranged 180 degrees opposite each other.