JP7130599B2 - Axis deviation measuring method, Axis deviation measuring device, and manufacturing method of stepped round bar - Google Patents

Description

The present invention relates to a measuring technique for measuring axial misalignment between the round bar regions of a stepped round bar body having a plurality of round bar regions with different diameters, and a manufacturing technology for the stepped round bar body using this measurement result. About.

Round bars such as crankshafts are manufactured by hot forging. Conventionally, a technique for measuring the diameter of a hot-forged round bar has been proposed (see, for example, Patent Document 1). In the technique described in Patent Document 1, an upper edge and a lower edge of the round bar are extracted from an image of the round bar taken from the side by the imaging unit. Also, the imaging distance between the imaging unit and the round bar is measured. Then, the diameter of the round bar is calculated based on the imaging distance, the position of the upper edge, and the position of the lower edge.

JP 2018-205256 A

On the other hand, conventionally known stepped round bar bodies have a plurality of round bar regions with different diameters. Also for this stepped round bar body, the diameter of each round bar region can be determined by the technique described in Patent Document 1 above. However, in the stepped round bar body, it is not enough to control the diameter of each round bar area, and it is necessary that the axial centers of each round bar area are aligned. Therefore, it is desired to obtain the axial deviation between each round bar region in the stepped round bar body.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems and to provide a method and apparatus for measuring the axial deviation, which can determine the axial deviation between the rod regions of the stepped rod body. and

Another object of the present invention is to provide a method of manufacturing a stepped round bar that can reduce the required axial misalignment.

The axial deviation measuring method according to the first aspect of the present invention includes:
A hot-forged stepped round bar body including a plurality of round bar regions with different diameters is rotated around an axis, and the plurality of round bars are rotated from the radially outer side of the stepped round bar body for each predetermined rotation angle. an image capturing step of capturing an image of two or more round bar regions among the bar regions as measurement target regions by an imaging unit;
a measuring step of measuring an imaging distance between each of the measurement target regions and the imaging unit for each of the predetermined rotation angles;
an extraction step of extracting an upper edge and a lower edge of each of the measurement target regions from the imaging result of the imaging unit for each of the predetermined rotation angles;
a diameter calculation step of calculating a diameter of each of the measurement target regions based on the imaging distance, the upper edge, and the lower edge for each of the predetermined rotation angles;
One of the plurality of round bar areas included in the measurement target area is defined as a reference round bar area, and the plurality of round bar areas included in the measurement target area are other than the reference round bar area. is defined as the measurement round bar area, the reference circle is determined based on the upper edge, the lower edge, and the diameter of each of the measurement target areas for each of the predetermined rotation angles. a difference calculation step of calculating a difference distance between the axis of the rod region and the axis of the measurement round bar region, and associating each of the calculated difference distances with the rotation angle of the stepped round bar;
A peak value of the differential distance is extracted, and based on the extracted peak value, an axial deviation amount of the axis of the measurement round bar region with respect to the axis of the reference round bar region is obtained and associated with the peak value. an axial deviation processing step of obtaining an axial deviation direction from the axial center of the reference round bar region to the axial center of the measurement round bar region based on the rotation angle of the stepped round bar body obtained;
is provided.

The axial deviation measuring device according to the second aspect of the present invention includes:
an imaging unit that captures two or more round bar regions of the plurality of round bar regions as measurement target regions from the radially outer side of a hot forged stepped round bar body including a plurality of round bar regions having different diameters;
a distance measuring unit that measures an imaging distance between each of the measurement target areas and the imaging unit;
a drive unit that rotates the stepped round bar around an axis;
A round-bar control unit that rotates the stepped round-bar by the driving unit, causes the imaging unit to image the measurement target area, and causes the distance measurement unit to measure each of the imaging distances for each predetermined rotation angle. When,
an extraction unit that extracts an upper edge and a lower edge of each of the measurement target regions from the imaging result of the imaging unit for each of the predetermined rotation angles;
a diameter calculation unit that calculates a diameter of each of the measurement target regions based on the imaging distance, the upper edge, and the lower edge for each of the predetermined rotation angles;
One of the plurality of round bar areas included in the measurement target area is defined as a reference round bar area, and the plurality of round bar areas included in the measurement target area are other than the reference round bar area. is defined as the measurement round bar area, the reference circle is determined based on the upper edge, the lower edge, and the diameter of each of the measurement target areas for each of the predetermined rotation angles. a difference calculation unit that calculates a difference distance between the axis of the rod region and the axis of the measurement round bar region, and associates each of the calculated difference distances with the rotation angle of the stepped round bar;
A peak value of the differential distance is extracted, and based on the extracted peak value, an axial deviation amount of the axis of the measurement round bar region with respect to the axis of the reference round bar region is obtained and associated with the peak value. an axis deviation processing unit that determines an axis deviation direction from the axis of the reference round bar area to the axis of the measurement round bar area based on the obtained rotation angle of the stepped rod body;
is provided.

In the first aspect or the second aspect, the difference distance between the axis of the reference round bar region and the axis of the measurement round bar region is calculated for each predetermined rotation angle, and the calculated difference distance is stepped. It is associated with the rotation angle of the round bar. Then, the peak value of the differential distance is extracted, and based on the extracted peak value, the amount of axial deviation of the axis of the measurement round bar area relative to the axis of the reference round bar area is obtained. Also, based on the rotation angle associated with the peak value, the axial deviation direction from the axial center of the reference round bar region to the axial center of the measurement round bar region is obtained. The peak value of the differential distance corresponds to the amount of axial deviation of the axis of the measurement round-bar area with respect to the axis of the reference round-bar area. Also, the rotation angle corresponding to the peak value corresponds to the axial deviation direction from the axis of the reference rod area to the axis of the measurement rod area. Therefore, according to the first aspect or the second aspect, the amount of misalignment of the axis of the measurement round bar area with respect to the axis of the reference round bar area and the axis of the measurement round bar area from the axis of the reference round bar area to the axis of the measurement round bar area. can be obtained.

In the first aspect, for example,
The axial misalignment processing step includes:
Extracting the maximum value Dmax and the minimum value Dmin of the difference distance as the peak value,
The axial deviation amount Dave is
Dave=(|Dmax|+|Dmin|)/2
may be obtained by

The maximum value Dmax and the minimum value Dmin of the difference distance are ideally
|Dmax|=|Dmin|
However, this may not be the case due to measurement errors and the like. On the other hand, according to this aspect, the amount of axial deviation Dave is
Dave=(|Dmax|+|Dmin|)/2
, the axial deviation amount Dave can be obtained with higher accuracy.

In the first aspect, for example,
The axial misalignment processing step includes:
The rotation angle θa associated with the maximum value Dmax and the rotation angle θb associated with the minimum value Dmin are extracted, and the smaller one of θa and θb is defined as θp, and the larger one as θq. The direction of misalignment θave is
θave={θp+(θq−180)}/2
may be obtained by

Ideally, the relationship between the rotation angle θp and the rotation angle θq is
θq−θp=180
However, this may not be the case due to measurement errors and the like. On the other hand, according to this aspect, the axial deviation direction θave is
θave={θp+(θq−180)}/2
, the axial deviation direction θave can be obtained with higher accuracy.

A method for manufacturing a stepped round bar body according to a third aspect of the present invention includes:
an axial deviation measuring method according to the first aspect;
a determination step of determining whether or not there is an axial deviation amount exceeding a predetermined threshold among the axial deviation amounts obtained in the axial deviation processing step;
when it is determined that there is an axial misalignment amount exceeding the predetermined threshold, identifying a measurement rod region corresponding to the maximum axial misalignment amount among the axial misalignment amounts exceeding the predetermined threshold;
a display step of displaying, on a display unit, the specified measurement round bar region, and the amount and direction of axial deviation of the specified measurement round bar region;
a hot forging step of performing hot forging according to an operator's operation;
is provided.

In this aspect, the measurement round bar region corresponding to the maximum shaft center shift amount among the shaft center shift amounts exceeding the predetermined threshold is specified, and the specified measurement round bar region and the center of the specified measurement round bar region The deviation amount and the axial deviation direction are displayed on the display unit, and hot forging is performed according to the operation of the operator. The display contents of the display unit allow the operator to know the measurement rod area for which the misalignment should be corrected, the amount of misalignment to be corrected, and the direction of the misalignment to be corrected. Therefore, according to this aspect, it is possible to manufacture a stepped round bar with reduced axial misalignment by the operator's operation according to the display contents of the display unit.

According to the present invention, in a hot-forged stepped round bar body including a plurality of round bar regions having different diameters, the amount of misalignment of the axis of the measurement round bar region with respect to the axis of the reference round bar region and the reference It is possible to obtain the axial deviation direction from the axis of the round bar area to the axis of the measured round bar area. Further, according to the present invention, it is possible to manufacture a stepped round bar with reduced axial misalignment.

1 is a block diagram showing the configuration of an axial deviation measuring device according to a first embodiment; FIG. FIG. 4 is a side view schematically showing a stepped round bar body manufacturing apparatus by hot forging. It is a figure which shows roughly the measurement state of a stepped round bar body by a sensor head. It is a figure which shows roughly the example of an image of a stepped round bar. Fig. 2 schematically shows upper and lower edges of a round bar area; It is a figure which shows the number of difference pixels roughly. It is a figure which shows roughly the calculated|required axial misalignment direction. FIG. 10 is a diagram schematically showing a difference distance for each rotation angle; 4 is a flow chart schematically showing an example of the operation of the shaft misalignment measuring device; 5 is a diagram schematically showing an image example of a stepped round bar different from that in FIG. 4; FIG. FIG. 11 is a diagram schematically showing the differential distance for each rotation angle obtained with the stepped round bar of FIG. 10; It is a block diagram which shows the structure of the stepped round bar manufacturing apparatus of 2nd Embodiment. 4 is a flow chart schematically showing an operation example of the stepped round bar manufacturing apparatus;

(Embodiment)
BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each drawing, the same code|symbol is used about the same component, and detailed description is abbreviate|omitted suitably.

(First embodiment)
FIG. 1 is a block diagram showing the configuration of the axial deviation measuring device of the first embodiment. FIG. 2 is a side view schematically showing a stepped round bar manufacturing apparatus by hot forging. FIG. 3 is a diagram schematically showing how a stepped round bar is measured by the sensor head. FIG. 4 is a diagram schematically showing an example of an image of a stepped round bar imaged by an imaging unit.

In FIG. 2, the operator operates the manipulator 20 and the hot forging press machine 30 to forge a hot object having a high temperature of about 600 to 1000° C. (in the first embodiment, the stepped round bar 10). A hot forging operation is performed to manufacture the stepped round bar body 10 . A manipulator 20 (corresponding to an example of a driving unit) can move one end of the stepped round bar 10 rotatably around the axis SC of the stepped round bar 10 and in a direction parallel to the axis SC. to grasp. In other words, the axis SC of the stepped round bar 10 is the rotation center of the manipulator 20 that grips the stepped round bar 10 . The hot forging press machine 30 has a hammer portion 31 and a bed portion 32 . The stepped round bar body 10 is placed on the bed portion 32 and hit by the hammer portion 31 .

While gripping the end of the stepped round bar 10 with the manipulator 20, the operator forges with the hot forging press machine 30 and rotates the stepped round bar 10 with the manipulator 20 to form the stepped round bar 10. Changing the hitting position is repeated to form the desired shape.

The stepped bar body 10 shown in FIG. 2 has three bar areas 11, 12, 13 with different diameters. Therefore, the round bar regions 11 , 12 , 13 are each placed on the bed portion 32 and hit by the hammer portion 31 . After aligning the axial centers of the round bar regions 11, 12, 13, the operator performs the hot forging operation until the round bar regions 11, 12, 13 have a predetermined diameter and a predetermined length. repeat. If the axial misalignment between the round bar regions 11, 12, and 13 is small, the axial centers can be aligned by shaving during machining in the post-process. However, if the axial misalignment is large, the cutting allowance will be insufficient. Therefore, it is extremely important to measure the axial misalignment.

In the first embodiment, the object to be measured by the axial misalignment measuring device 100 is the stepped round bar 10 for which the hot forging operation is temporarily interrupted during hot forging. Alternatively, the measurement target of the axial deviation measuring device 100 may be the stepped round bar body 10 immediately after hot forging is completed.

As shown in FIG. 1 , the axial deviation measuring device 100 includes a sensor head 40 , an actuator 115 , a display section 120 , an input section 125 , a manipulator 20 and a control circuit 140 . Sensor head 40 includes imaging section 105 and distance measuring section 110 . The control circuit 140 includes a memory 150, a central processing unit (CPU) 160, and peripheral circuits (not shown).

As shown in FIG. 3 , the sensor head 40 is held on a holding base 50 and arranged on the side of the stepped round bar 10 and near the same height as the stepped round bar 10 . The holding table 50 is attached to the support plate 60 so as to be movable in the vertical direction and in the depth direction of FIG. 3 (that is, the direction parallel to the axis SC of the stepped round bar 10).

The imaging unit 105 is connected to the control circuit 140, and according to the control of the control circuit 140, images the round bar areas 11, 12, and 13 from the outside of the stepped round bar body 10 in the radial direction as measurement target areas. In addition, in FIG. 4, all of the round bar areas 11, 12, and 13 are set as the measurement target area, but the present invention is not limited to this. Two or more of the round-bar areas 11, 12, and 13 may be used as measurement target areas.

The imaging unit 105 is arranged at a position where the round bar areas 11 , 12 and 13 of the stepped round bar body 10 are within the range of the angle of view θ of the imaging unit 105 . The imaging unit 105 is, for example, a camera equipped with a CCD image sensor or a CMOS image sensor. The imaging unit 105 images the round bar regions 11, 12, and 13 of the stepped round bar body 10 including the background. An infrared transmission filter that transmits only infrared light is attached to the lens of the imaging unit 105 . Therefore, as shown in FIG. 4, the image I10 of the stepped rod 10 is bright and the background is dark. In FIG. 4, image I10 of stepped rod 10 includes images I11, I12, and I13 of rod regions 11, 12, and 13, respectively.

The distance measuring unit 110 is connected to the control circuit 140 and measures the imaging distance between the imaging unit 105 and the surface of each of the round bar regions 11, 12, and 13, which are measurement target regions, under the control of the control circuit 140. FIG. The distance measuring unit 110 is, for example, a laser rangefinder, irradiates the surface of the stepped rod 10 with the laser beam 110A, receives the reflected light, and based on the received light, the imaging unit 105 and the surface of each of the round bar regions 11, 12, and 13 are measured.

The actuator 115 is connected to the control circuit 140 and moves the holder 50 holding the sensor head 40 with respect to the support plate 60 under the control of the control circuit 140 . For example, when measuring the imaging distance from the surface of the round bar region 12 of the stepped round bar 10, the actuator 115 moves the sensor head 40 in a direction parallel to the axis SC of the stepped round bar 10. to position the sensor head 40 in front of the round bar region 12 . Alternatively, the stepped round bar body 10 may be moved by the manipulator 20 to position the round bar region 12 in front of the sensor head 40 .

The display unit 120 includes, for example, a liquid crystal display panel. Under the control of the control circuit 140, the display unit 120 displays the measured axial deviation amount and axial deviation direction of each round bar region, for example, as will be described later. Note that the display unit 120 is not limited to a liquid crystal display panel. Display 120 may include other panels such as an organic electroluminescent (EL) panel.

Input unit 125 includes, for example, a mouse or a keyboard. When operated by an operator, the input unit 125 outputs an operation signal indicating the content of the operation (for example, start of measurement of shaft misalignment) to the control circuit 140 . If the display unit 120 is a touch panel display, the touch panel display may also serve as the input unit 125 instead of the mouse or keyboard.

The memory 150 is configured by, for example, a semiconductor memory or the like. The memory 150 includes, for example, read only memory (ROM), random access memory (RAM), electrically erasable programmable ROM (EEPROM), and the like. The CPU 160 operates according to the control program of the first embodiment stored, for example, in the ROM of the memory 150 to control a round bar body control section 161, an edge extraction section 162 (corresponding to an example of an extraction section), and a diameter calculation section 163. , the difference calculator 164 , and the axial deviation processor 165 .

FIG. 5 is a diagram schematically showing upper edges and lower edges of the round bar regions 11, 12, 13 extracted by the edge extractor 162. FIG. FIG. 6 is a diagram schematically showing the number of difference pixels calculated by the difference calculator 164. As shown in FIG. FIG. 7 is a diagram schematically showing the axial deviation direction obtained by the axial deviation processing section 165. As shown in FIG. FIG. 8 is a diagram schematically showing the differential distance for each rotation angle obtained by the axial deviation processor 165. As shown in FIG. FIG. 9 is a flow chart schematically showing an example of the operation of the shaft misalignment measuring device 100. As shown in FIG. The operation of the shaft misalignment measuring device 100 will be described according to the flowchart of FIG. 9 while referring to FIGS. 1 and 5 to 8. FIG.

In step S100 of FIG. 9 (corresponding to an example of an imaging step, corresponding to an example of a measuring step), the round bar control unit 161 controls the imaging unit 105 and the actuator 115 to Each of them is imaged, the distance measurement unit 110 and the actuator 115 are controlled, and the imaging distance between each of the round bar regions 11, 12, and 13 and the imaging unit 105 is measured.

For example, as shown in FIG. 4, when the image capturing unit 105 captures an image of the entire round bar regions 11, 12, and 13 at once, when the image capturing unit 105 captures an image of the stepped round bar body 10, , the rod body control unit 161 does not have to move the sensor head 40 in the horizontal direction by the actuator 115 .

However, in order to obtain the upper edge and the lower edge of each of the round bar regions 11, 12, 13 with high accuracy, the actuator 115 moves the sensor head 40 in the horizontal direction so that the imaging unit 105 moves to the round bar regions 11, 12. , 13 in front of each, and the round bar regions 11, 12, 13 are individually imaged.

Further, in order to obtain the diameters of the respective round bar regions 11, 12, 13 with high accuracy, the center of the image 200 and the position corresponding to the axis SC of the stepped round bar body 10 should match (that is, extend horizontally). It is preferable that the optical axis of the imaging unit 105 is perpendicular to the axis SC of the stepped rod 10).

In order to accurately measure the imaging distance between each of the round-bar areas 11, 12, and 13 and the imaging unit 105, the round-bar body control unit 161 controls the actuator 115 so that the horizontally extending distance measuring unit It is preferable to dispose the distance measuring unit 110 in front of each of the round bar regions 11, 12, and 13 at a position where the laser beam 110A from 110 intersects the axis SC of the stepped round bar body 10 at right angles.

In step S105 (corresponding to an example of an extraction step), the edge extracting unit 162 applies an edge enhancement filter to the pixel values of the pixels of the image 200 to extract the upper edges of the round-bar regions 11, 12, and 13, respectively. and extract the bottom edge. 5, upper edge 11U and lower edge 11D of round bar area 11 are extracted, upper edge 12U and lower edge 12D of round bar area 12 are extracted, upper edge 13U and lower edge 13U of round bar area 13 are extracted. 13D has been extracted.

In step S110 (corresponding to an example of a diameter calculation step), the diameter calculator 163 calculates diameters of the round bar regions 11, 12, and 13 by the method described in Patent Document 1 above. That is, diameter calculation section 163 calculates the following based on the imaging distance between each of round-bar areas 11, 12, and 13 and imaging section 105 and the positions of the upper and lower edges of each of round-bar areas 11, 12, and 13. Diameters D11 [mm], D12 [mm] and D13 [mm] of the round bar regions 11, 12 and 13 are calculated.

In step S115 (corresponding to an example of the difference calculation step), the difference calculation unit 164 calculates the difference distance between the axis of the reference rod area and the axis of the measurement rod area, and converts the calculated difference distance into the rotation angle. , and stored in the memory 150 .

Here, one round bar area (round bar area 11 in FIG. 4) among a plurality of round bar areas (round bar areas 11, 12, and 13 in FIG. 4) included in the measurement target area is the reference round bar area. is defined as In addition, among the plurality of round bar areas (round bar areas 11, 12, and 13 in FIG. 4) included in the measurement target area, the remaining round bar areas other than the reference round bar area (round bar area 11 in FIG. 4) ( In FIG. 4, the round bar areas 12, 13) are defined as measuring round bar areas.

Hereinafter, as a specific example of this step, a procedure for calculating the differential distance between the axis of the round bar area 11 as the reference round bar area and the axis of the round bar area 12 as the measurement round bar area will be described.

First, as shown in FIG. 5, difference calculation unit 164 virtually sets measurement line 11M parallel to the Y-axis that intersects upper edge 11U and lower edge 11D in image 200, and calculates upper edge 12U and lower edge 11D. A measurement line 12M parallel to the Y-axis is virtually set to intersect the lower edge 12D. Next, the difference calculation unit 164 obtains the diameter pixel number P11 [pixels] of the round bar region 11 on the measurement line 11M of the image 200, and calculates the diameter pixel number P12 [pixels] of the round bar region 12 on the measurement line 12M. ].

Next, as shown in FIG. 6, the difference calculator 164 obtains the axial center coordinates 11Y of the round bar region 11, which is the midpoint of the upper edge 11U and the lower edge 11D on the measurement line 11M of the image 200. , on the measurement line 12M, the axial center coordinate 12Y of the round bar region 12, which is the midpoint between the upper edge 12U and the lower edge 12D, is determined. Then, as shown in FIG. 6, the difference calculation unit 164 calculates the number of difference pixels Δd [pixels] between the axial coordinates 11Y of the round-bar region 11 and the axial coordinates 12Y of the round-bar region 12 in the image 200. ,
Δd=12Y-11Y
Ask by

Next, the difference calculation unit 164 calculates the conversion coefficient K [mm/ pixels],
K=D11/P11
Ask by Then, the difference calculation unit 164 calculates the difference distance D [mm] as
D=K×Δd
Ask by The difference calculation unit 164 associates the calculated difference distance D [mm] with the rotation angle of the stepped round bar 10 and stores it in the memory 150 .

In step S120, the axial deviation processing unit 165 determines whether or not the stepped round bar 10 has rotated 360 degrees. If the stepped round bar 10 has not rotated 360 degrees (NO in step S120), the process proceeds to step S125. On the other hand, if stepped round bar 10 has rotated 360 degrees (YES in step S120), the process proceeds to step S130.

In step S125, the axial deviation processing unit 165 controls the manipulator 20 to rotate the stepped round bar 10 by a predetermined rotation angle (for example, 5 degrees). After that, the process returns to step S100, and steps S100 to S120 are repeated.

In FIG. 8, the horizontal axis represents the rotation angle [degrees] of the stepped round bar 10, and the vertical axis represents the differential distance [mm]. "0" on the vertical axis corresponds to the position of the axis of the round bar area 11, which is the reference round bar area. FIG. 8 shows difference distances stored in the memory 150 in association with the rotation angle of the stepped rod body 10 when YES is determined in step S120. That is, FIG. 8 shows differential distances for rotation angles from 0 degrees to 360 degrees.

In step S130 (corresponding to an example of an axial deviation processing step), the axial deviation processing unit 165 performs rotation corresponding to the maximum and minimum difference distances and the maximum and minimum values for each measurement rod region. Extract angles. In the example of FIG. 8, the axial deviation processing unit 165 extracts the maximum value Dnax, the minimum value Dmin, the rotation angle θa corresponding to the maximum value Dmax, and the rotation angle θb corresponding to the minimum value Dmin of the difference distance D. .

In step S<b>135 (corresponding to an example of the axial deviation processing step), the axial deviation processing section 165 calculates the axial deviation amount and the axial deviation direction of each measurement round bar region and displays them on the display section 120 .

Considering the principle of shaft misalignment, ideally, the amount of misalignment should be:
|Dmax|=|Dmin|
is. Therefore, for simplicity, the axial deviation processing unit 165 may set the axial deviation amount to Dmax. However, in practice, due to measurement errors,
|Dmax|=|Dmin|
There are some things that cannot be done. Therefore, in the first embodiment, the axial deviation processing unit 165 sets the axial deviation amount Dave as
Dave=(|Dmax|+|Dmin|)/2 (Formula 1)
Calculated by As a result, the amount of misalignment can be obtained with higher accuracy than when the amount of misalignment is set to Dmax.

Also, since the rotation angle θa and the rotation angle θb are in opposite directions, ideally,
θb−θa=180
is. Therefore, for simplicity, the axial deviation processing unit 165 may set the axial deviation direction to θa or θb. However, in practice, due to measurement errors,
θb−θa=180
There are some things that cannot be done.

Although .theta.b>.theta.a in FIG. 8, .theta.b<.theta.a may be satisfied depending on the rotational angular position of the stepped round bar 10 at the start of measurement. Therefore, when the smaller one of θa and θb is defined as θp, and the larger one is defined as θq, the axial deviation processing unit 165 determines the axial deviation direction θave as follows:
θave={θp+(θq−180)}/2 (Formula 2)
Calculated by As a result, the direction of axial deviation can be obtained with higher accuracy than when the direction of axial deviation is set to θp or θq.

Then, the axial deviation processing unit 165 displays the calculated axial deviation amount Dave and the axial deviation direction θave on the display unit 120 in association with the round bar region 12 . The axial deviation processing unit 165 also obtains the axial deviation amount and the axial deviation direction of the round bar region 13, which is the measurement round bar region, with respect to the round bar region 11, which is the reference round bar region, in the same procedure. It is displayed on the display unit 120 in association with the round bar area 13 .

Here, the axial deviation direction will be described with reference to FIGS. 7 and 8. FIG. The axial deviation direction is the direction from the axial center of the round bar region 11 to the axial center of the round bar region 12 . The paper surface of FIG. 7 is a plane perpendicular to the axis of the round bar region 11 . 7, the axis of the round bar region 11 is defined as the origin O11, and the rotation start angle of the stepped round bar body 10 (that is, the rotation angle of the horizontal axis in FIG. 8 corresponds to 0 degrees) is It is defined as the X-axis passing through the origin O11. As shown in FIG. 7, the axial deviation direction θave of the axis of the round bar region 12 with respect to the axis of the round bar region 11 is from the X axis to a straight line L11 passing through the origin O11 based on the rotation angles θp and θq. is represented by an angle around the origin O11.

FIG. 10 is a diagram schematically showing an example of an image of the stepped round bar 70 different from that in FIG. FIG. 11 is a diagram schematically showing the differential distance for each rotation angle obtained with the stepped round bar 70 of FIG. In FIG. 11, the horizontal axis represents the rotation angle [degrees] of the stepped round bar 70, and the vertical axis represents the differential distance [mm]. "0" on the vertical axis corresponds to the position of the axis of the round bar region B1, which is the reference round bar region.

The stepped round bar body 70 shown in FIG. 10 includes four round bar regions B1-B4. In FIGS. 10 and 11, all four round bar areas B1 to B4 are the measurement target areas. Then, one round bar region (round bar region B1 in FIGS. 10 and 11) of the plurality of round bar regions (round bar regions B1 to B4 in FIGS. 10 and 11) included in the measurement target region is used as a reference. Defined as the round bar area. Also, of the plurality of round-bar areas (round-bar areas B1 to B4 in FIGS. 10 and 11) included in the measurement target area, the remainder other than the reference round-bar area (round-bar area B1 in FIGS. 10 and 11) A round bar area (round bar areas B2 to B4 in FIGS. 10 and 11) is defined as a measurement round bar area.

FIG. 11 shows the differential distance for each rotation angle of the round bar areas B2 to B4, which are the measurement round bar areas, with respect to the round bar area B1, which is the reference round bar area. In FIG. 10, the maximum value of the difference distance of the round bar area B3 is D1, the minimum value is D2, and the peak value of the difference distance (the absolute value of the maximum value and the minimum value) is the largest in the round bar area B3. It's becoming

In the case of FIG. 11, the axial misalignment processing unit 165, according to the procedure of FIG.
θ3ave={θ3a+(θ3b−180)}/2
and the axial deviation amount D3ave of the round bar region B3 is obtained by
D3ave=(|D1|+|D2|)/2
Ask by The axial deviation processing unit 165 similarly obtains the axial deviation direction and the axial deviation amount of the other round bar regions B2 and B4. The axial deviation processing unit 165 displays the determined axial deviation direction and axial deviation amount on the display unit 120 in association with the round bar regions B2, B3, and B4, respectively.

In step S135, the axial deviation processing unit 165 may display only the data of the round bar region with the maximum axial deviation amount on the display unit 120. FIG. That is, in the example of FIG. 11 , the axial deviation processing section 165 may display only the axial deviation amount and the axial deviation direction of the round bar region B3 on the display section 120 . Alternatively, the axial deviation processing unit 165 may also display the difference distance for each rotation angle on the display unit 120 as shown in FIGS. 8 and 11 .

As described above, in the axial deviation measuring device 100 and the axial deviation measuring method implemented in the first embodiment, in the stepped round bar body 10, the round bar region 11, which is the reference round bar region, A differential distance between the axis and the axis of the round bar regions 12 and 13, which are the measured round bar regions, is obtained for each rotation angle, and its peak value is extracted. Therefore, according to the first embodiment, it is possible to obtain the axial deviation direction and the axial deviation amount of the axis of the measurement round bar area relative to the axis of the reference round bar area based on the peak value.

Further, in the first embodiment, since the amount of axial deviation is obtained by the above (Equation 1), it is possible to obtain the amount of axial deviation with higher accuracy. In addition, in the first embodiment, since the direction of axial misalignment is obtained by the above (Equation 2), the direction of axial misalignment can be obtained with higher accuracy.

Further, in the first embodiment, the determined axial deviation direction and axial deviation amount are displayed on the display unit 120 in association with the measurement round bar region (step S135 in FIG. 9). Therefore, according to the first embodiment, by checking the display unit 120, the operator can check whether the amount of axial deviation in the stepped round bar bodies 10 and 70 is within the allowable range, and whether or not the axial deviation can be corrected. It is possible to determine the direction to be taken and the amount of pressure to be applied by the hot forging press 30 when making corrections.

(Second embodiment)
FIG. 12 is a block diagram showing the configuration of a stepped round bar manufacturing apparatus 100A of the second embodiment. In the second embodiment, the target of the stepped round bar manufacturing apparatus 100A is a stepped round bar whose forging operation is temporarily interrupted during hot forging.

As shown in FIG. 12, the stepped round bar manufacturing apparatus 100A includes a hot forging press 30 in addition to each part of the axial deviation measuring apparatus 100 (FIG. 1). Further, the stepped rod manufacturing apparatus 100A includes a control circuit 140A, a memory 150A and a CPU 160A in place of the control circuit 140, memory 150 and CPU 160 of the axial deviation measuring apparatus 100 (FIG. 1). The CPU 160A operates according to the control program of the second embodiment stored, for example, in the ROM of the memory 150A to control the round bar body control section 161, the edge extraction section 162, the diameter calculation section 163, the difference calculation section 164, the axis center It functions as a deviation processing section 165 and a hot forging control section 171 .

The hot forging control unit 171 controls the manipulator 20 and the hot forging press machine 30 based on the operator's operation to hot forge the stepped round bar body, so that each of the plurality of round bar regions has a predetermined shape. A stepped round bar body having a diameter and a predetermined length is manufactured.

FIG. 13 is a flow chart schematically showing an example of the operation of the stepped round bar manufacturing apparatus 100A. In FIG. 13, steps S100-S135 are the same as steps S100-S135 in FIG.

In step S200 (corresponding to an example of a determination step) following step S135, the hot forging control unit 171 determines whether there is an axial deviation amount exceeding a predetermined threshold among the axial deviation amounts calculated in step S135. determine whether or not If there is an axial deviation amount exceeding the predetermined threshold (YES in step S200), the process proceeds to step S205. On the other hand, if there is no shaft misalignment amount exceeding the predetermined threshold (NO in step S200), the operation of FIG. 13 ends. The predetermined threshold may be set according to the accuracy required for the stepped round bar.

In step S205 (corresponding to an example of the specifying step), the hot forging control section 171 specifies the measurement round bar region corresponding to the maximum axial deviation amount among the axial deviation amounts exceeding the predetermined threshold value. In step S210 (corresponding to an example of the display step), the hot forging control unit 171 displays the specified measurement round bar region, and the axial deviation amount and the axial deviation direction of the specified measurement round bar region. 120. In step S<b>215 (corresponding to an example of the hot forging step), the hot forging control section 171 performs hot forging according to the operation of the operator using the input section 125 . After that, the operation of FIG. 13 ends.

As described above, in the stepped round bar manufacturing apparatus 100A and the stepped round bar manufacturing method mounted thereon in the second embodiment, the shaft center shift amount among the shaft center shift amount exceeding the predetermined threshold value is specified, the specified measurement round bar region, its axial deviation amount and axial deviation direction are displayed on the display unit 120, and hot forging is performed according to the operator's operation. . By confirming the display unit 120, the operator can grasp the measurement rod area in which the axial misalignment should be corrected, the direction in which the axial misalignment is corrected, and the amount of correction. Therefore, according to the second embodiment, by operating the stepped round bar manufacturing apparatus 100A according to the grasped content, the operator can manufacture a stepped round bar with reduced axial misalignment. can.

10, 70 stepped round bar body 20 manipulator 30 hot forging press machine 105 imaging section 110 distance measurement section 161 round bar body control section 162 edge extraction section 163 diameter calculation section 164 difference calculation section 165 axial deviation processing section 171 hot Forging control part

Claims (5)

A hot-forged stepped round bar body including a plurality of round bar regions with different diameters is rotated around an axis, and the plurality of round bars are rotated from the radially outer side of the stepped round bar body for each predetermined rotation angle. an image capturing step of capturing an image of two or more round bar regions among the bar regions as measurement target regions by an imaging unit;
a measuring step of measuring an imaging distance between each of the measurement target regions and the imaging unit for each of the predetermined rotation angles;
an extraction step of extracting an upper edge and a lower edge of each of the measurement target regions from the imaging result of the imaging unit for each of the predetermined rotation angles;
a diameter calculation step of calculating a diameter of each of the measurement target regions based on the imaging distance, the upper edge, and the lower edge for each of the predetermined rotation angles;
One of the plurality of round bar areas included in the measurement target area is defined as a reference round bar area, and the plurality of round bar areas included in the measurement target area are other than the reference round bar area. is defined as the measurement round bar area, the reference circle is determined based on the upper edge, the lower edge, and the diameter of each of the measurement target areas for each of the predetermined rotation angles. a difference calculation step of calculating a difference distance between the axis of the rod region and the axis of the measurement round bar region, and associating each of the calculated difference distances with the rotation angle of the stepped round bar;
A peak value of the differential distance is extracted, and based on the extracted peak value, an axial deviation amount of the axis of the measurement round bar region with respect to the axis of the reference round bar region is obtained and associated with the peak value. an axial deviation processing step of obtaining an axial deviation direction from the axial center of the reference round bar region to the axial center of the measurement round bar region based on the obtained rotation angle of the stepped round bar body;
A misalignment measurement method comprising: The axial misalignment processing step includes:
Extracting the maximum value Dmax and the minimum value Dmin of the difference distance as the peak value,
The axial deviation amount Dave is
Dave=(|Dmax|+|Dmin|)/2
sought by
2. The axial deviation measuring method according to claim 1. The axial misalignment processing step includes:
The rotation angle θa associated with the maximum value Dmax and the rotation angle θb associated with the minimum value Dmin are extracted, and the smaller one of θa and θb is defined as θp, and the larger one as θq. The direction of misalignment θave is
θave={θp+(θq−180)}/2
sought by
3. The method for measuring axial deviation according to claim 2. an imaging unit that captures two or more round bar regions of the plurality of round bar regions as measurement target regions from the radially outer side of a hot forged stepped round bar body including a plurality of round bar regions having different diameters;
a distance measuring unit that measures an imaging distance between each of the measurement target areas and the imaging unit;
a drive unit that rotates the stepped round bar around an axis;
A round-bar control unit that rotates the stepped round-bar by the driving unit, causes the imaging unit to image the measurement target area, and causes the distance measurement unit to measure each of the imaging distances for each predetermined rotation angle. When,
an extraction unit that extracts an upper edge and a lower edge of each of the measurement target regions from the imaging result of the imaging unit for each of the predetermined rotation angles;
a diameter calculation unit that calculates a diameter of each of the measurement target regions based on the imaging distance, the upper edge, and the lower edge for each of the predetermined rotation angles;
One of the plurality of round bar areas included in the measurement target area is defined as a reference round bar area, and the plurality of round bar areas included in the measurement target area are other than the reference round bar area. is defined as the measurement round bar area, the reference circle is determined based on the upper edge, the lower edge, and the diameter of each of the measurement target areas for each of the predetermined rotation angles. a difference calculation unit that calculates a difference distance between the axis of the rod region and the axis of the measurement round bar region, and associates each of the calculated difference distances with the rotation angle of the stepped round bar;
A peak value of the differential distance is extracted, and based on the extracted peak value, an axial deviation amount of the axis of the measurement round bar region with respect to the axis of the reference round bar region is obtained and associated with the peak value. an axis deviation processing unit that determines an axis deviation direction from the axis of the reference round bar area to the axis of the measurement round bar area based on the obtained rotation angle of the stepped rod body;
A misalignment measuring device comprising: The axial deviation measuring method according to any one of claims 1 to 3;
a determination step of determining whether or not there is an axial deviation amount exceeding a predetermined threshold among the axial deviation amounts obtained in the axial deviation processing step;
when it is determined that there is an axial misalignment amount exceeding the predetermined threshold, identifying a measurement rod region corresponding to the maximum axial misalignment amount among the axial misalignment amounts exceeding the predetermined threshold;
a display step of displaying, on a display unit, the specified measurement round bar region, and the amount and direction of axial deviation of the specified measurement round bar region;
a hot forging step of performing hot forging according to an operator's operation;
A method for manufacturing a stepped round bar.

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