JP2017170503A - Metal processing apparatus and method for manufacturing metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance a product quality in such a manner that abnormality of condition of contact between a component which supports a metal and the metal is detected with a higher accuracy during bending processing of the metal.SOLUTION: A metal processing apparatus comprises: a delivery system which delivers a long metal in a longer direction; a support mechanism which guides and supports the delivered metal at one portion in the longer direction; and a holding mechanism which holds the metal at another portion of said metal, and adds a flexure load to the metal. The support mechanism is provided with a measurement mechanism which measures a friction force between itself and the support mechanism when the metal is delivered, and a processing reaction force which acts on the support mechanism when the flexure load is added onto the metal.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a metal processing apparatus that performs bending on a metal material, and a metal material manufacturing method using the metal processing apparatus.

  Metal structural members used in automobiles and various machines are required to have high strength, light weight, and small size. For example, in the automobile industry, demands for increasing the strength and weight of automobile parts are becoming stricter from the viewpoint of improving fuel efficiency and collision safety.

  Many such structural members have a bent shape. Therefore, various techniques for bending a long metal material such as a steel pipe have been developed.

  For example, in Patent Documents 1 and 2, a feed mechanism that holds one end of a steel pipe and feeds the steel pipe in the longitudinal direction thereof, a support mechanism that guides and supports the fed steel pipe, and a heating mechanism that locally heats the steel pipe And a cooling mechanism that cools the heated portion of the steel pipe, and a clamping mechanism that sandwiches the steel pipe at the other end of the steel pipe and adds a bending load to the heated portion of the steel pipe. Is disclosed.

  In the technique described in Patent Document 1, in the hot bending apparatus, driving of the feeding mechanism and the clamping mechanism is controlled based on a predetermined control pattern so that the steel pipe after bending has a target quality. At the same time, driving of at least one of the support mechanism, the heating mechanism, and the cooling mechanism is controlled based on displacement information and / or temperature information of the steel pipe being processed. Further, in the technique described in Patent Literature 2, in the hot bending apparatus, when the load and / or acceleration acting on the manipulator that is the clamping mechanism is measured, and the deviation between the measured value and the target value is large, Control that issues an alarm and interrupts machining is performed.

  As described above, according to the techniques described in Patent Documents 1 and 2, since the bending process is controlled based on the state of the steel pipe or the clamping mechanism (manipulator) being processed, the bending is performed with high accuracy so as to obtain the target quality. Processing can be performed. The techniques described in Patent Documents 1 and 2 relate to a technique called so-called three-dimensional hot bending and quenching (3DQ: 3 Dimensional Hot Bending and Quench).

  Further, for example, Patent Document 3 discloses a bending apparatus that sandwiches a steel pipe by a bending die and a clamping die that can revolve around the bending die, and bends the pipe by revolving the clamping die. The bending apparatus provided with the punch for terminal processing inserted in the both ends of the said steel pipe is disclosed. According to the bending apparatus described in Patent Document 3, it is possible to easily perform terminal processing of the steel pipe as well as bending of the steel pipe.

JP 2008-23573 A JP 2012-228714 A JP 2006-159282 A

  Here, while processing using the bending apparatus, a supporting member (for example, a member corresponding to the supporting mechanism in the hot bending apparatus described in Patent Documents 1 and 2) and the steel pipe are supported. The contact state between the two may unintentionally change. Such changes in the contact state are considered to be, for example, wear on the surface of the support member, penetration of silicon between the support member and the steel pipe, deterioration in parallelism due to fine movement of the installation position of the support member, etc. It is done. If processing is continued as it is even though there is an abnormality in the contact state, the quality of the product may deteriorate, for example, the surface of the steel pipe may become wrinkled. Further, if the contact state becomes unstable, the position where the support member supports the steel pipe becomes unstable, a desired bending load cannot be applied, and the processing accuracy may be lowered.

  In order to deal with this phenomenon, at present, the state of a product is investigated by 100% inspection after processing, and a process for removing surface wrinkles and a process for correcting a shape are performed as necessary. However, these inspection operations, correction operations, and the like are complicated and lead to time and steel pipe loss.

  In view of such circumstances, there has been a demand for a technique for detecting abnormalities in the contact state between a member supporting a steel pipe and the steel pipe in the bending apparatus. If an abnormality in the contact state can be detected during processing, the processing can be interrupted and the support member can be replaced or repaired as appropriate, so that the occurrence of defective products can be suppressed and an improvement in yield can be expected. However, Patent Documents 1 to 3 do not describe any technique for detecting the contact state between the support member and the steel pipe during such processing. This is considered because it is difficult to stably detect the contact state during processing.

  For example, as an index indicating the contact state between the support member and the steel pipe, it is conceivable to measure the friction coefficient between them. However, in the conventional bending apparatus, the contact state between the support member and the steel pipe in the sliding portion of the support member with the steel pipe can always change due to the geometric contact condition between the support pipe and the steel pipe. The geometric contact conditions are, for example, the distance between the contact position between the two and the bending position of the steel pipe, the area of the contact portion between the two, and the like. If these conditions change, the contact state can also change, making it difficult to measure the stable frictional force. Accordingly, it is difficult to stably detect the contact state.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to detect an abnormality in a contact state between a member supporting a metal material and the metal material with higher accuracy during processing. Accordingly, it is an object of the present invention to provide a new and improved metal processing apparatus capable of improving product quality, and a metal material manufacturing method using the metal processing apparatus.

  In order to solve the above problems, according to an aspect of the present invention, a feeding mechanism that feeds a long metal material in the longitudinal direction, and a support mechanism that guides and supports the fed metal material at one site in the longitudinal direction, A holding mechanism that holds the metal material at another part of the metal material and applies a bending load to the metal material, and the support mechanism includes the support mechanism when the metal material is fed out. There is provided a metal processing apparatus provided with a measurement mechanism for measuring a reaction force acting on the support mechanism when a bending force is applied to the metal material and a bending reaction force between the metal material and the metal material.

  Further, the metal processing apparatus includes a friction coefficient calculation unit that calculates a friction coefficient between the support mechanism and the metal material based on the friction force and the processing reaction force measured by the support mechanism, and the friction A contact state abnormality detection unit that detects a contact state abnormality between the support mechanism and the metal material based on a coefficient, and when the contact state abnormality detection unit detects the contact state abnormality The processing control unit that controls the driving of the feeding mechanism and the clamping mechanism for issuing a warning by the alarm device or bending the metal material may stop the processing for the metal material.

  Further, in the metal processing apparatus, the measurement mechanism of the support mechanism includes a guide shoe that supports the metal material during bending, and a portion of the guide shoe that faces the metal material has the feeding direction. It may have an arc shape in the plane to include, and may have a linear shape in a plane orthogonal to the feed direction.

  Further, in the metal processing apparatus, the measurement mechanism of the support mechanism is loaded with the bending load in a direction perpendicular to the force in the feed direction of the metal material acting on the guide shoe and the feed direction. It may further include a load cell capable of detecting at least a directional force.

  In addition, the metal processing apparatus is provided at a subsequent stage of the support mechanism, and is provided at a subsequent stage of the heating mechanism and a heating mechanism that heats a part of the metal material in the longitudinal direction. A cooling mechanism for cooling the heated portion, and the bending mechanism applies a bending load to the portion heated by the heating mechanism of the metal material by the clamping mechanism, thereby bending the metal material. Processing may be performed.

  In order to solve the above-described problem, according to another aspect of the present invention, a feeding mechanism that feeds a long metal material in the longitudinal direction, and guides and supports the fed metal material at one portion in the longitudinal direction. A metal member manufacturing method using a metal processing apparatus comprising: a support mechanism; and a clamping mechanism that clamps the metal material at another part of the metal material and applies a bending load to the metal material, The measurement mechanism provided in the support mechanism causes a frictional force with the support mechanism when the metal material is fed out, and a processing reaction force acting on the support mechanism when the bending load is applied to the metal material. A method of manufacturing a metal material is provided.

  Further, in the method for manufacturing the metal material, a friction coefficient between the support mechanism and the metal material is calculated based on the friction force and the processing reaction force measured by the support mechanism, and the friction coefficient is calculated. Based on the detection of an abnormality in the contact state between the support mechanism and the metal material, if an abnormality in the contact state is detected, an alarm indicating that an abnormality in the contact state has occurred, or the metal Processing on the material may be stopped.

  In the metal material manufacturing method, the measurement mechanism of the support mechanism includes a guide shoe that supports the metal material during bending, a force in the feed direction of the metal material that acts on the guide shoe, and the feed. A load cell that is capable of detecting at least a force in a direction perpendicular to the direction and in which the bending load is applied, and a portion of the guide shoe that faces the metal material is an in-plane including the feeding direction. And may have a linear shape in a plane orthogonal to the feed direction.

  Further, in the metal material manufacturing method, the metal processing apparatus is provided at a subsequent stage of the support mechanism, and is provided at a subsequent stage of the heating mechanism that heats a part of the metal material in the longitudinal direction, and the heating mechanism. A cooling mechanism that cools a portion of the metal material heated by the heating mechanism, and a bending load is applied to the portion of the metal material heated by the heating mechanism by the clamping mechanism. By doing so, the metal material may be bent.

  As described above, according to the present invention, in bending a metal material, the product quality is improved by detecting the abnormality in the contact state between the member supporting the metal material and the metal material more accurately during the processing. It becomes possible to make it.

It is a figure which shows the example of 1 structure of the metal processing apparatus which concerns on this embodiment. It is sectional drawing in the AA cross section of the support mechanism shown in FIG. The support mechanism shown in FIG. 1 is shown in more detail reflecting the actual shape. It is a figure for demonstrating the contact conditions of the said supporting member and metal material in the case of using the conventional supporting member. It is a figure for demonstrating the contact conditions of the said supporting member and metal material at the time of using the supporting member which concerns on this embodiment. It is a block diagram which shows the function structure of the control apparatus shown in FIG. It is a flowchart which shows an example of the process sequence of the manufacturing method of the metal member which concerns on this embodiment. It is a figure for demonstrating the bending direction on the process conditions in an Example. It is a graph which shows the measurement result of a friction coefficient. It is the photograph which image | photographed the surface of the metal material after actually bending in condition (1). It is the photograph which image | photographed the surface of the metal material after performing a bending process in condition (2) actually. It is the photograph which image | photographed the surface of the non-slip | slipping tape on a guide shoe after actually bending in condition (2).

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

(1. Configuration of metal processing equipment)
With reference to FIG. 1, the structure of the metal processing apparatus which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a diagram illustrating a configuration example of a metal processing apparatus according to the present embodiment. FIG. 1 shows a state in which a horizontal section of the metal processing apparatus according to this embodiment is viewed from above. In addition, in the drawings shown below including FIG. 1, the size of some of the constituent members may be exaggerated for the sake of explanation, and the relative sizes of the constituent members illustrated in the respective drawings. This does not necessarily accurately represent the magnitude relationship between actual components.

  Referring to FIG. 1, a metal processing apparatus 10 according to the present embodiment includes a delivery mechanism 110 that delivers a metal material 1 intermittently or continuously in a longitudinal direction thereof, and a support mechanism that guides and supports the delivered metal material 1. 120, a heating mechanism 130 for locally heating the metal material 1, a cooling mechanism 140 for cooling the heated portion of the metal material 1, and a bent portion of the heated metal material 1 with the metal material 1 interposed therebetween A clamping mechanism 150 for applying a load is arranged in this order along the longitudinal direction of the metal material 1. Further, the metal processing apparatus 10 controls the driving of the delivery mechanism 110, the heating mechanism 130, the cooling mechanism 140, and the clamping mechanism 150, so that the metal material 1 is heated while moving the metal material 1 in the longitudinal direction. A control device 160 that performs inter-bending processing is provided. The metal processing apparatus 10 is a metal processing apparatus compatible with so-called 3DQ.

  Here, the following description demonstrates the case where the metal material 1 is a steel pipe as an example. For example, the metal processing apparatus 10 is a steel pipe having an outer diameter of about φ10 to 200 mm and a thickness of about 1 to 8 mm. However, this embodiment is not limited to this example, and the metal material 1 may be another member as long as it is a rod-shaped metal material such as a solid steel bar. Moreover, the metal material 1 should just be a metal which can be bent, and the material is not limited to steel. The metal material 1 may be, for example, various metals such as aluminum, aluminum alloy, and titanium in addition to steel and special steel.

(Sending mechanism)
The delivery mechanism 110 holds one end of the metal material 1 and moves the metal material 1 continuously or intermittently in the longitudinal direction under the control of the control device 160. As the delivery mechanism 110, for example, the same delivery mechanism of a conventional metal processing apparatus according to 3DQ exemplified in Patent Documents 1 and 2 may be used. For example, the delivery mechanism 110 can be composed of a drive source such as an AC servo motor or a hydraulic servo motor, or a mechanical element such as a ball screw that converts the rotational power of the drive source into a linear motion. Alternatively, the delivery mechanism 110 may be configured by a cylinder device such as a hydraulic cylinder or an air cylinder. When the end of the metal material 1 is pressed by the ball screw or the piston rod of the cylinder device, the metal material 1 is pushed out in the longitudinal direction.

  In the following description, the direction in which the metal material 1 is pushed out by the delivery mechanism 110 is also referred to as the x-axis direction. Two directions orthogonal to the x-axis direction are also referred to as a y-axis direction and a z-axis direction, respectively. The z-axis direction corresponds to the vertical direction (that is, the vertical direction).

(Support mechanism)
The support mechanism 120 guides and supports the metal material 1 at one site in the longitudinal direction of the metal material 1. The support mechanism 120 is configured by a support member that is disposed so as to cover the outer periphery of the metal material 1 at one part in the longitudinal direction of the metal material 1, for example.

  Here, when an abnormality occurs in the contact state between the support mechanism 120 and the metal material 1, it is considered that the friction coefficient between the support mechanism 120 and the metal material 1 changes greatly. For example, when a foreign substance such as silicon enters between the support mechanism 120 and the metal material 1, it is assumed that the friction coefficient is larger than a value considered to be normal. On the other hand, when the gap between the support mechanism 120 and the metal material 1 becomes larger than the design value, it is assumed that the friction coefficient becomes smaller than a value considered normal.

  Thus, the coefficient of friction between the support mechanism 120 and the metal material 1 can be an index representing the contact state between the support mechanism 120 and the metal material 1. Therefore, in the present embodiment, paying attention to this, the contact state between the support mechanism 120 and the metal material 1 is evaluated by measuring the friction coefficient between the support mechanism 120 and the metal material 1.

  Specifically, in this embodiment, the support mechanism 120 is provided with a measurement mechanism that detects a load acting on itself. The measurement mechanism includes a reaction force that acts on the support mechanism 120 due to a bending load applied to the metal material 1 (that is, a processing reaction force in the bending direction), and the metal material 1 is sent in the longitudinal direction to support the support mechanism 120. And a frictional force acting on (that is, a frictional force in the feed direction) can be measured at least. Values for these forces measured by the support mechanism 120 are transmitted to the controller 160. The control device 160 divides the measured friction force in the feed direction (hereinafter also referred to as a measured friction force) by the measured reaction force in the bending direction (hereinafter also referred to as a measured processing reaction force). Thus, the friction coefficient can be obtained, and the abnormality of the contact state can be detected based on the friction coefficient.

  Even if only the processing reaction force is measured, if the value greatly deviates from the normal value, it is confirmed that some abnormality has occurred in the contact state between the support mechanism 120 and the metal material 1. There is a possibility that it can be detected. However, the processing reaction force can also change due to, for example, variations in the thickness of the steel pipe that is the metal material 1. In other words, the factor causing the processing reaction force to vary is not necessarily the change in the contact state between the support mechanism 120 and the metal material 1. Therefore, when the contact state is evaluated based on the measurement value of the processing reaction force, the contact state may not be accurately evaluated. On the other hand, in this embodiment, as described above, based on the friction coefficient between the support mechanism 120 and the metal material 1, the contact state between the two is evaluated. Since the friction coefficient can be an index that directly represents the contact state between the two, according to the present embodiment, the contact state can be more accurately evaluated.

  In FIG. 1, for simplicity, the support mechanism 120 is simplified and illustrated as a simple rectangular member, but the actual shape of the support mechanism 120 is different from that illustrated. A more detailed configuration of the support mechanism 120 including the configuration of the measurement mechanism will be described again below (2. Configuration of the support mechanism).

(Heating mechanism)
The heating mechanism 130 is configured by, for example, a heating coil disposed so as to cover the outer periphery of the metal material 1 at one site in the longitudinal direction, and locally heats the metal material 1. When the high frequency current is applied to the heating coil under the control of the control device 160, the metal material 1 is locally heated. In addition, as the heating mechanism 130, the thing similar to the heating mechanism of the metal processing apparatus which concerns on the conventional 3DQ illustrated by patent document 1, 2, for example may be used.

(Cooling mechanism)
The cooling mechanism 140 is constituted by, for example, a water-cooling jacket disposed so as to cover the outer periphery of the metal material 1 at one site in the longitudinal direction, and cools the site heated by the heating mechanism 130 of the metal material 1. Alternatively, the cooling mechanism 140 may be configured by a nozzle that sprays a cooling medium onto the metal material 1. The metal material 1 is cooled by appropriately controlling the supply of the cooling medium to the cooling jacket and / or the nozzle under the control of the control device 160. In addition, as the cooling mechanism 140, the thing similar to the cooling mechanism of the metal processing apparatus which concerns on the conventional 3DQ illustrated by patent document 1, 2, for example may be used.

  In the metal processing apparatus 10, the metal material 1 is actually bent at a position corresponding to the heating mechanism 130. Therefore, in the metal processing apparatus 10, in order to improve processing accuracy, the heating mechanism 130, the support mechanism 120 provided in the front stage of the heating mechanism 130, and the cooling mechanism 140 provided in the subsequent stage of the heating mechanism 130 are: It is preferable to arrange them as close as possible.

(Clamping mechanism)
The clamping mechanism 150 is configured by a manipulator of an industrial robot, for example, and clamps an end opposite to the end gripped by the feeding mechanism 110 of the metal material 1 and applies a bending load to the metal material 1. Append. In the present embodiment, the manipulator constituting the clamping mechanism 150 is configured to have at least six degrees of freedom, and loads on the metal material 1 in the x-axis direction, the y-axis direction, and the z-axis direction, and these A load in the rotation direction around three axes can be applied. Therefore, according to the metal processing apparatus 10, a three-dimensional bending process for the metal material 1 can be realized. However, the configuration of the clamping mechanism 150 is not limited to this example, and the clamping mechanism 150 may have another configuration as long as a bending load can be applied to the metal material 1 in a predetermined direction. As the holding mechanism 150, for example, the same holding mechanism as that of a conventional metal processing apparatus according to 3DQ exemplified in Patent Documents 1 and 2 may be used.

(Control device)
The control device 160 processes the metal material 1 into a desired shape by controlling the driving of the delivery mechanism 110, the heating mechanism 130, the cooling mechanism 140, and the clamping mechanism 150 in conjunction with each other. Specifically, the controller 160 heats the metal material 1 locally while the delivery mechanism 110 delivers the metal material 1 in the longitudinal direction at a predetermined speed according to the processing conditions according to the product shape. At the same time, the clamping mechanism 150 applies a bending load to the heated portion of the metal material 1, and immediately after that, the cooling mechanism 140 cools the heated portion of the metal material 1 to drive these mechanisms. To control. Thereby, the process of the metal material 1 according to a desired product shape is implement | achieved.

  In the present embodiment, the control device 160 has a function of detecting an abnormality in the contact state of the support mechanism 120 with the metal material 1. Specifically, the metal processing apparatus 10 is provided with a friction coefficient DB 170 that stores information about the normal range of the friction coefficient between the support mechanism 120 and the metal material 1 for each product and each processing site. . The friction coefficient DB 170 is configured by a storage device that can store various types of information, such as a magnetic storage device such as an HDD (Hard Disk Drive), a semiconductor storage device, an optical storage device, or a magneto-optical storage device.

  The control device 160 obtains a friction coefficient between the support mechanism 120 and the metal material 1 based on the frictional force and the processing reaction force measured by the support mechanism 120 during the processing. Then, the control device 160 compares the obtained friction coefficient with the normal range of the friction coefficient stored in the friction coefficient DB 170. When the obtained friction coefficient is out of the normal range, the control device 160 determines that an abnormality has occurred in the contact state between the support mechanism 120 and the metal material 1 (that is, detects an abnormality in the contact state). To do). Moreover, the control apparatus 160 determines with the contact state of the support mechanism 120 and the metal material 1 being normal, when the calculated | required friction coefficient is in a normal range. In the metal processing apparatus 10, when an abnormality is detected in the contact state between the support mechanism 120 and the metal material 1, an abnormality in the contact state is given to an operator or the like, for example, stopping the processing or issuing an alarm. A predetermined action for notification is executed. The function of the control device 160 will be described in more detail later (3. Functional configuration of the control device).

  When an alarm is issued in response to detection of an abnormality in the contact state, the metal processing apparatus 10 is provided with an alarm device configured by, for example, an audio output device such as a speaker and / or a display device such as a lamp. Can be. When a contact state abnormality is detected, the alarm device is driven under the control of the control device 160, and a warning that a contact state abnormality has occurred may be issued by sound and / or light.

  The overall configuration of the metal processing apparatus 10 according to the present embodiment has been described above with reference to FIG.

(2. Configuration of support mechanism)
With reference to FIG.2 and FIG.3, the structure of the support mechanism 120 is demonstrated in detail. 2 is a cross-sectional view of the support mechanism 120 shown in FIG. FIG. 3 shows the support mechanism 120 shown in FIG. 1 in more detail, reflecting the actual shape. 2 and 3 show a configuration example of the support mechanism 120 when the metal material 1 is a steel pipe (so-called square tube) having a rectangular cross-sectional shape. However, in this embodiment, the metal material 1 is not limited to a square tube, and the support mechanism 120 can be similarly configured even when the metal material 1 is a steel pipe having a circular cross-sectional shape.

  Referring to FIG. 2, the support mechanism 120 includes a plurality of support members 121. As shown in the drawing, each support member 121 can be disposed on each of the four sides of the rectangular cross section of the metal material 1.

  2 and 3, the gap between the metal material 1 and each support member 121 is exaggerated, but actually, the gap is appropriately moved and supported properly. Adjusted accordingly. For example, if the gap is too small, the metal material 1 slides with the inner wall of the support member 121, and smooth movement of the metal material 1 in the axial direction may be hindered. On the other hand, if the gap is too large, the position of the central axis of the metal material 1 is not stable, which may make it difficult to apply a desired bending load during processing. Therefore, the gap is appropriately adjusted so that both the movement and support of the metal material 1 are appropriately performed.

  As shown in FIGS. 2 and 3, the support member 121 is configured by attaching a three-component force load cell 123 and a guide shoe 124 to be stacked in this order on one surface of a substantially rectangular parallelepiped base material 122. The Further, as illustrated, the support member 121 is disposed so that the guide shoe 124 faces the metal material 1. In the illustrated configuration example, the support member 121 is provided with two combinations of the three-component force load cell 123 and the guide shoe 124 on one base material 122, and these combinations are predetermined in the feeding direction of the metal material 1. They are arranged and arranged so as to be spaced apart.

  The three component force load cell 123 is a force sensor that can detect forces in three axial directions orthogonal to each other. The three-component force load cell 123 is attached so as to detect forces acting in the illustrated x-axis direction, y-axis direction, and z-axis direction. As the three-component force load cell 123, various known ones such as one using a strain gauge or one using a piezoelectric element can be used.

  The guide shoe 124 is a member that supports the metal material 1 during bending. The guide shoe 124 is made of, for example, metal, ceramic, resin, or the like. The guide shoe 124 is attached to the upper part of the three-component force load cell 123, and the three-component force load cell 123 can detect a force acting on the guide shoe 124. When the metal material 1 is bent, the metal material 1 is pressed against the guide shoe 124 arranged in the bending direction. Therefore, the support member 121 is guided by the three component force load cell 123 during the bending process. The working reaction force acting on the shoe 124 in the bending direction can be measured. Further, in the support member 121, the friction force in the feeding direction acting on the guide shoe 124 when the metal material 1 is fed in the longitudinal direction can be measured by the three component force load cell 123. The three-component force load cell 123 is configured to be able to measure a friction force in a range of about 100 g to 900 kg, for example.

  As a specific shape of the guide shoe 124, as shown in the figure, the guide shoe 124 has a circular arc shape in a plane that includes the feeding direction (x-axis direction in the drawing) of the metal material 1 at a portion facing the metal material 1. And a linear shape in a plane including a direction (y-axis direction or z-axis direction in the drawing) orthogonal to the feeding direction of the metal material 1. That is, the portion of the guide shoe 124 facing the metal material 1 has a shape in which an arc shape in a plane including the feeding direction of the metal material 1 is continuous in a direction orthogonal to the feeding direction.

  According to such a shape, when the metal material 1 comes into contact with the guide shoe 124 at the time of bending or feeding, the guide shoe 124 has a linear portion extending in a direction orthogonal to the feeding direction (the metal material 1 described above). The metal material 1 is contacted only at a portion corresponding to a linear shape in a plane including a direction orthogonal to the feed direction. That is, in the longitudinal direction, the guide shoe 124 comes into contact with the metal material 1 only at one arc-shaped place.

  Here, as described above, in the present embodiment, a friction coefficient is calculated based on the measured friction force and processing reaction force, and the contact state between the support mechanism 120 and the metal material 1 (that is, based on the friction coefficient (that is, The contact state between the guide shoe 124 and the metal material 1) is evaluated. Therefore, in order to evaluate the contact state more accurately, it is necessary to calculate the friction coefficient with higher accuracy. According to the present embodiment, the friction coefficient can be calculated with higher accuracy by using the three-component force load cell 123 as a force sensor and devising the shape of the guide shoe 124 as described above.

  First, the effect of using the three component force load cell 123 will be described. In order to accurately obtain the coefficient of friction between the guide shoe 124 and the metal material 1, it is necessary to measure the frictional force and the processing reaction force acting on the guide shoe 124 at the same time. Here, when the frictional force and the processing reaction force are measured by different force sensors, the frictional force at the same time and the frictional force at the same time due to variations in response speed from when the force is actually applied until the force is detected. It is not always possible to accurately measure the processing reaction force. On the other hand, in this embodiment, by using the three-component force load cell 123 as a force sensor as described above, it is possible to simultaneously measure the friction force and the processing reaction force with one force sensor. Therefore, the friction coefficient calculated based on these measured values can be calculated with higher accuracy.

  Next, the effect of devising the shape of the guide shoe 124 will be described. In order to obtain the coefficient of friction between the guide shoe 124 and the metal material 1 with high accuracy, it is necessary to measure the frictional force and the processing reaction force at the same location of the guide shoe 124. When the frictional force and work reaction force are measured at different locations, it is necessary to make corrections according to the distance between the measurement locations when calculating the friction coefficient, making the process complicated and correcting This is because the fractional accuracy may also be reduced. According to the present embodiment, by devising the shape of the guide shoe 124, the guide shoe 124 and the metal material 1 come into contact with each other only at one place in the longitudinal direction as described above. The frictional force and the processing reaction force can be measured at a location, that is, at the same location. Therefore, the friction coefficient can be obtained with high accuracy.

  Further, by forming the shape of the guide shoe 124 as described above, the following effects can be further obtained. First, during operation, when the metal material 1 is processed continuously, the tip of the metal material 1 collides with the support member 121, and the metal material 1 is not smoothly inserted between the support members 121. Therefore, there is a concern that it is difficult to stably measure the frictional force and the processing reaction force. On the other hand, in the present embodiment, the tip of the metal material 1 is inserted between the support members 121 by forming the guide shoe 124 in an arc shape in a plane including the feeding direction of the metal material 1. At this time, the tip of the metal material 1 is easily inserted between the support members 121 by being guided by the arc shape. That is, since physical interference between the tip of the metal material 1 and the support member 121 is alleviated, it is possible to stably measure the frictional force and the processing reaction force.

  Further, as described above, the portion of the guide shoe 124 facing the metal material 1 has an arc shape in a plane including the feed direction of the metal material 1, but a linear shape in a plane orthogonal to the feed direction. Have If the portion of the guide shoe 124 facing the metal material 1 has a three-dimensional curved surface shape such as a spherical surface, the purpose of the guide shoe 124 and the metal material 1 contacting at one place is achieved. Although it can be done, the guide shoe 124 and the metal material 1 come into contact only at one point on the curved surface. In this case, an excessive force acts on the contact portion, and it may be difficult to stably measure the frictional force and the processing reaction force. On the other hand, the guide shoe 124 and the metal material 1 are linearly formed by forming the portion of the guide shoe 124 that faces the metal material 1 so as to have an arc shape only within a predetermined plane as described above. Therefore, the frictional force and the processing reaction force can be measured more stably.

  Thus, according to the present embodiment, the portion of the guide shoe 124 that faces the metal material 1 has an arc shape in a plane including the feed direction of the metal material 1 and is orthogonal to the feed direction of the metal material 1. By configuring so as to have a linear shape in the plane including the direction, the frictional force and the processing reaction force acting on the guide shoe 124 can be measured more accurately and stably. Therefore, the friction coefficient calculated based on these measured values can also be calculated more accurately and stably.

  In addition, it is preferable that the base material 122, the three-component force load cell 123, and the guide shoe 124 that constitute the support member 121 are made of a material having low elasticity (it is difficult to elastically deform). This is because if the elasticity of the material of each member constituting the support member 121 is large and the deflection when contacting the metal material 1 is large, it may be difficult to accurately measure the frictional force and the processing reaction force. . By forming each member constituting the support member 121 from a material having relatively low elasticity, the rigidity of the entire support member 121 can be increased, and the measurement accuracy of the frictional force and the processing reaction force can be further improved. .

  Here, as shown in the figure, the support member 121 may be configured by providing two combinations of the three-component force load cell 123 and the guide shoe 124 on one base material 122. Further, the combination of the three component force load cell 123 and the guide shoe 124 may be arranged so as to be arranged at a predetermined interval in the feeding direction of the metal material 1. By configuring the support member 121 in this way, it is possible to detect an abnormality in the contact state with higher accuracy.

  For example, consider the case where the metal material 1 is bent in the negative direction of the y-axis. In this case, unlike the configuration example shown in the figure, for example, the support member 121 is configured by providing only one combination of the three-component load cell 123 and the guide shoe 124 on one base material 122, and the support member 121 is When the metal material 1 is disposed so as to be sandwiched in the y-axis direction at the same position in the feed direction, when the metal material 1 is bent in the negative y-axis direction, the metal material 1 is positioned in the negative y-axis direction. Only the guide shoe 124 to be contacted. Accordingly, the friction force and the processing reaction force can be measured only at the one guide shoe 124.

  On the other hand, in the illustrated configuration example, the metal material 1 includes a guide shoe 124 (guide shoe X in the drawing) positioned in the positive direction of the y axis in the drawing and in the negative direction of the x axis, and in the drawing. The guide shoe 124 (guide shoe Y in the figure) located in the negative direction of the y-axis and in the positive direction of the x-axis comes into contact with the guide shoes X and Y. Force can be measured. That is, the friction force and the reaction force can be measured at two different locations for the same processing step. Therefore, the friction coefficient can be obtained at two different locations for the same machining process, so that the abnormality of the contact state can be evaluated in more detail.

  In addition, according to the support member 121 according to the present embodiment, the contact condition between the guide shoe 124 and the metal material 1 during processing can be kept substantially constant because the guide shoe 124 has the shape as described above. There is an advantage that the contact state (that is, the friction coefficient) can be detected more stably. This point will be described in more detail with reference to FIGS. 4 and 5 in comparison with a conventional support member having another shape. Here, as an example, as a contact condition, the distance between the contact position of the support member 121 and the metal material 1 and the bending position of the metal material 1 and the area of the contact portion between the support member 121 and the metal material 1 will be described.

  FIG. 4 is a diagram for explaining contact conditions between the support member and the metal material when a conventional support member is used. FIG. 4 shows a state in which a horizontal cross section in the vicinity of the support mechanism 620 when the metal material 1 is bent by a conventional metal processing apparatus is viewed from above. As shown in the drawing, the support mechanism 620 is configured by disposing a substantially rectangular parallelepiped support member 621 so as to sandwich the metal material 1 on both sides in the y-axis direction of the metal material 1. Although not explicitly shown in FIG. 4, the support member 621 may be similarly disposed on both sides of the metal material 1 in the z-axis direction. Thus, conventionally, in a general metal processing apparatus corresponding to 3DQ similar to the metal processing apparatus 10, a substantially rectangular parallelepiped steel material or the like is used as the support member 621 of the support mechanism 620. That is, in the conventional metal processing apparatus, the support member 621 and the metal material 1 come into contact with each other through one plane of the support member 621. Here, the conventional metal processing apparatus is the same as the metal processing apparatus 10 according to this embodiment except for the configuration of the support mechanism 620.

Consider a case where the metal material 1 is bent in the positive direction of the y-axis in a conventional metal processing apparatus. FIG. 4A shows a state in the vicinity of the support mechanism 620 when the bending amount is relatively small. In this case, as shown in the drawing, the support member 621 and the metal material 1 are formed in the vicinity of the corner in the negative direction of the x axis of the support member 621 arranged in the negative direction of the y axis (contact point 201 in the figure) It is considered that the contact is mainly made at two points near the corner in the positive direction of the x axis of the support member 621 arranged in the positive direction (contact point 203 in the figure). For convenience, if the bending position of the metal material 1 is the exit of the heating mechanism 130, the distance between the contact position and the bending position when the amount of bending is relatively small is the distance between the contact points 201 and 203 and the heating mechanism 130. The distances d ₁ and d _{2 from the} exit can be considered.

On the other hand, FIG. 4B shows a state in the vicinity of the support mechanism 620 when the amount of bending is relatively large. In this case, in an extreme case, as shown in the drawing, the support member 621 and the metal material 1 are regions having a predetermined length from the corner of the support member 621 arranged in the negative direction of the y axis in the negative direction of the x axis. In the figure, the contact region 205) is considered to be mainly in contact. Therefore, the distance between the contact position and the bending position when the bending amount is relatively large can be regarded as the distance d ₃ between the contact region 205 and the outlet of the heating mechanism 130. Figure 4 (b), the conveniently shows the approximate center of the contact region 205, the distance between the outlet of the heating mechanism 130 as the distance d _3.

  Thus, when bending is performed using the conventional support member 621 having a substantially rectangular parallelepiped shape, the area of the contact portion between the support member 621 and the metal material 1 changes according to the amount of bending. Specifically, when the bending amount is relatively small, the contact portion can be regarded as a substantially point-like portion (contact points 201 and 203) on the xy plane, but when the bending amount is relatively large, The contact portion can be regarded as a portion (contact region 205) having a predetermined length in the x-axis direction in the xy plane. Further, with the change in the area of the contact portion, the distance between the contact position of the support member 621 and the metal material 1 and the bending position also changes according to the amount of bending.

  From the above consideration, when bending is performed using the support member 621 having a conventional substantially rectangular parallelepiped shape, the contact condition between the support member 621 and the metal material 1 can be changed depending on the processing conditions. In this case, for example, even if the support member 621 is provided with a friction coefficient measurement mechanism (for example, a force sensor for measuring the frictional force in the x-axis direction and the processing reaction force in the bending direction), the measurement mechanism is installed. There may occur a situation in which the value of the coefficient of friction measured in accordance with the position changes. Therefore, it is difficult to stably detect the contact state (that is, the friction coefficient) between the support member 621 and the metal material 1. 4B, when the contact portion between the support member 621 and the metal material 1 has a predetermined area, the metal material 1 adds the support member 621 during the bending process. Since the processed reaction force is dispersed on the contact surface, it is more difficult to accurately measure the processing reaction force.

  On the other hand, FIG. 5 is a figure for demonstrating the contact conditions of the said supporting member 121 and the metal material 1 at the time of using the supporting member 121 which concerns on this embodiment. FIG. 5 also shows a state in which the horizontal cross section in the vicinity of the support mechanism 120 when the metal material 1 is bent by the metal processing apparatus 10 according to this embodiment is viewed from above, as in FIG.

Similarly, in the metal processing apparatus 10 according to the present embodiment, considering the case where the metal material 1 is bent in the positive direction of the y-axis, the support member 121 and the metal material 1 are arranged in the negative direction of the y-axis as shown in the figure. Near the tip of the arcuate shape of the guide shoe 124 positioned in the negative x-axis direction of the support member 121 (contact point 207 in the figure) and the positive x-axis of the support member 121 arranged in the positive y-axis direction. It is considered that contact is mainly made at two points in the vicinity of the arcuate tip of the guide shoe 124 positioned in the direction (contact point 209 in the figure). The positions of the contact points 207 and 209 hardly change even if the bending amount changes. Therefore, when the support member 121 according to the present embodiment is used, the distance between the contact position and the bending position is the distances d ₄ and d ₅ between the contact points 207 and 209 and the outlet of the heating mechanism 130, respectively. Further, the distances d ₄ and d ₅ can be regarded as being substantially constant regardless of the bending amount.

  As described above, when bending is performed using the support member 121 according to the present embodiment, even if the bending amount changes, the area of the contact portion between the support member 121 and the metal material 1 and the support member 121 are changed. In addition, the distance between the contact position and the bending position of the metal material 1 does not change.

  From the above consideration, when bending is performed using the support member 121 according to the present embodiment, the contact condition between the support member 121 and the metal material 1 does not change even when the processing conditions change. . Specifically, even when the processing conditions change, the support member 121 and the metal material 1 are in contact at the contact points 207 and 209 described above. Therefore, considering the contact at the contact points 207 and 209, the friction coefficient value can be measured with higher accuracy by providing the three-component force load cell 123 as described above. That is, the contact state between the support member 121 and the metal material 1 can be detected more stably. In addition, as described above, the contact portions between the support member 121 and the metal material 1 are the contact points 207 and 209 that are point-like portions in the xy plane, and thus are supported from the metal material 1 during bending. The processing reaction force applied to the member 121 acts on the contact points 207 and 209 in a concentrated manner. Therefore, the processing reaction force can be measured more accurately, and the friction coefficient can be measured with higher accuracy.

  The configuration of the support mechanism 120 and the configuration of the support member 121 that configures the support mechanism 120 have been described above in detail.

  Here, as described above, since the support mechanism 120 can be disposed in the vicinity of the heating mechanism 130 and the cooling mechanism 140, the support member 121 (that is, the three-component load cell 123 and the guide shoe 124) includes these heating mechanisms. 130 and the cooling mechanism 140 (specifically, it is difficult to be influenced by induction heating by the heating mechanism 130 and that the cooling water splashed from the cooling mechanism 140 does not deteriorate). It is done. Therefore, for example, in order to avoid the influence of induction heating, the distance between the support member 121 and the heating mechanism 130 may be appropriately adjusted in consideration of the heating capability of the heating mechanism 130 and the like. Further, for example, the surface of the guide shoe 124 may be plated in order to avoid the influence of splashing of cooling water.

  In order to avoid malfunction due to the effects of the heating mechanism 130 and the cooling mechanism 140, it is desirable that the force sensor mounted on the support member 121 be as small as possible. According to the present embodiment, by using the three-component load cell 123 capable of measuring both frictional force and machining reaction force as the force sensor, the force sensor can be miniaturized, and the above-described high-frequency noise and cooling water scattering can be achieved. It is hard to be influenced by. As a result, the frictional force and the processing reaction force can be measured with higher accuracy.

  In the configuration example illustrated in FIG. 2, the support mechanism 120 is configured by the four support members 121. However, the number of the support members 121 configuring the support mechanism 120 is not limited to this example, and may be arbitrary. . The support member 121 is appropriately arranged and arranged so that the support member 121 is positioned at least in the bending direction so that the processing reaction force can be measured to calculate the friction coefficient. Good. For example, if it is desired to measure the friction coefficient between the support mechanism 120 and the metal material 1 when the metal material 1 is bent in the y-axis direction, the metal material 1 is supported at least at a position sandwiching the metal material 1 in the y-axis direction. The member 121 should just be arrange | positioned.

  Further, all of the plurality of support members 121 arranged so as to surround the metal material 1 do not have to have a mechanism for measuring frictional force and processing reaction force. That is, the support mechanism 120 may be configured by a support member 121 having a friction force and work reaction force measurement mechanism as shown in FIG. 3 and a support member having no measurement mechanism. This is because it is sufficient that the support member 121 having a measurement function is disposed only in the bending direction in the machining process in which it is desired to obtain the friction coefficient (that is, to measure the machining reaction force and the friction force). For example, if it is desired to measure the friction coefficient between the support mechanism 120 and the metal material 1 when the metal material 1 is bent in the y-axis direction, measure at least at a position where the metal material 1 is sandwiched in the y-axis direction. A support member 121 having a mechanism may be disposed, and a support member having no measurement mechanism may be provided at a position where the metal material 1 is sandwiched in the z-axis direction. In this case, the support member that does not have the measurement mechanism only needs to fulfill the function of guiding and supporting the metal material 1 and may be, for example, a substantially rectangular parallelepiped steel material.

  Further, in the configuration example shown in FIG. 3, the support member 121 is configured by providing two combinations of the three component force load cell 123 and the guide shoe 124 on one base material 122. It is not limited to such an example. For example, when the metal material 1 is bent in the negative direction of the y axis in the illustrated configuration example, the metal material 1 contacts the guide shoe X and the guide shoe Y as described above. Therefore, for example, when it is desired to obtain only the friction coefficient when the metal material 1 is bent in the negative direction of the y-axis, the support member 121 is a combination of the three component force load cell 123 and the guide shoe 124 on one base material 122. Only one set is provided and the support member 121 may be arranged so that the guide shoe 124 is located at a position corresponding to the guide shoes X and Y. As described above, the number and position of the combination of the three-component force load cell 123 and the guide shoe 124 in one support member 121 may be appropriately set in consideration of the bending direction in the machining process for which a friction coefficient is desired.

  In the configuration example described above, the support member 121 has the three-component force load cell 123. However, the present embodiment is not limited to this example. In order to calculate the friction coefficient, it is only necessary to measure the frictional force in the feeding direction and the processing reaction force in the bending direction. Therefore, the support member 121 depends on the relationship between the arrangement position and the bending direction of the metal material 1. Instead of the three-component force load cell 123, a two-component force load cell may be provided. For example, the support member 121 provided so as to sandwich the metal material 1 in the y-axis direction is for obtaining a friction coefficient when the metal material 1 is bent in the y-axis direction. A two-component force load cell capable of detecting a load in the y-axis direction may be mounted. On the other hand, for example, the support member 121 provided so as to sandwich the metal material 1 in the z-axis direction is for obtaining a friction coefficient when the metal material 1 is bent in the z-axis direction. A two-component force load cell capable of detecting loads in the x-axis direction and the z-axis direction may be mounted.

  Furthermore, in this embodiment, the support member 121 should just be comprised so that a friction force and a process reaction force can be measured, and the structure may be arbitrary. For example, the shape of the guide shoe 124 is not necessarily illustrated, and may be a substantially rectangular parallelepiped shape. Further, the force sensor is not necessarily the three-component force load cell 123. For example, a force sensor for measuring a friction force and a force sensor for measuring a processing reaction force are mounted on the support member 121, respectively. May be. When the shape of the guide shoe 124 is a substantially rectangular parallelepiped shape, or when the frictional force and the machining reaction force are measured by different force sensors, the frictional force and the machining reaction force may not be measured at the same location. In that case, for example, the distance between the measurement points is estimated based on the shape and processing conditions of the guide shoe 124, the position of the force sensor, and the like, and the friction is obtained after appropriately correcting the estimation result. A coefficient may be obtained. However, by configuring the support member 121 as illustrated, the friction coefficient can be obtained without performing such correction processing as described above, and therefore the illustrated configuration is preferable for the support member 121. It can be said that there is.

(3. Functional configuration of control device)
With reference to FIG. 6, the functional configuration of control device 160 shown in FIG. 1 will be described. FIG. 6 is a block diagram showing a functional configuration of the control device 160 shown in FIG. In FIG. 6, the friction coefficient DB 170 is also shown together with the control device 160 for explanation.

  The control device 160 detects an abnormality in the contact state between the support mechanism 120 and the metal material 1 based on the frictional force and the processing reaction force measured by the support mechanism 120. The control device 160 is, for example, various processors such as a CPU (Central Processing Unit) and a DSP (Digital Signal Processor), or an information processing device on which the processor is mounted. The functions of the control device 160 can be realized by the processor constituting the control device 160 operating according to a predetermined program.

  Referring to FIG. 6, the control device 160 has a friction coefficient calculation unit 161 and a contact state abnormality detection unit 162 as its functions. In addition, although illustration is abbreviate | omitted, in order to bend the metal material 1 in the desired shape according to a product and a process shape as the function, the control apparatus 160 is the sending mechanism 110 of the metal processing apparatus 10, and the heating mechanism 130. Also, a machining control unit that appropriately controls the driving of the cooling mechanism 140 and the clamping mechanism 150 is provided. Since the function of the processing control unit in the control device 160 is the same as the function of a general existing metal processing device according to 3DQ, detailed description thereof is omitted here.

  The friction coefficient calculation unit 161 calculates a friction coefficient between the support mechanism 120 and the metal material 1 based on the friction force and the processing reaction force measured by the support mechanism 120. Specifically, the friction coefficient calculation unit 161 can obtain the friction coefficient by dividing the measured friction force by the measured processing reaction force. In addition, when the frictional force and the processing reaction force cannot be measured at the same location due to circumstances such as the configuration of the support member 121, the friction coefficient calculation unit 161 uses information such as the distance between the measurement locations. Alternatively, the friction coefficient may be obtained after appropriate correction. The friction coefficient calculation unit 161 provides information about the calculated friction coefficient to the contact state abnormality detection unit 162.

  The contact state abnormality detection unit 162 detects an abnormality in the contact state between the support mechanism 120 and the metal material 1 based on the calculated friction coefficient. Specifically, the contact state abnormality detection unit 162 compares the friction coefficient calculated by the friction coefficient calculation unit 161 with the normal range of the friction coefficient stored in the friction coefficient DB 170, thereby calculating the calculated friction coefficient. Is determined to be within the normal range.

  For example, the friction coefficient DB 170 stores the relationship between products and processed parts and the normal range of the friction coefficient as shown in Table 1 below. The relationship can vary depending on the processing conditions such as the material of the metal material 1 (carbon concentration of the steel pipe, etc.), shape (tube diameter of the steel pipe, etc.), feed rate, bending amount (radius R of the bent portion), etc. The relationship is acquired in advance for each product and each processed part, and stored in the friction coefficient DB 170. In addition, the normal range of the friction coefficient according to the product and the processing part may be appropriately set as a friction coefficient range that does not cause a defect in the product based on, for example, actual data, experimental results, and / or simulation results. .

  The contact state abnormality detection unit 162 can obtain information on a product and a processing site that are currently being processed (that is, the frictional force and the reaction force are measured by the support mechanism 120) from the above-described processing control unit. Based on the information, the contact state abnormality detection unit 162 acquires information about the normal range of the friction coefficient for the corresponding product and the processed part from the friction coefficient DB 170. Then, the contact state abnormality detection unit 162 compares the friction coefficient calculated by the friction coefficient calculation unit 161 with the lower limit value and the upper limit value of the acquired normal range of the friction coefficient.

  When the calculated friction coefficient is out of the normal range, the contact state abnormality detection unit 162 determines that an abnormality has occurred in the contact state between the support mechanism 120 and the metal material 1 (that is, the contact state). ) When the calculated friction coefficient is within the normal range, the contact state abnormality detection unit 162 determines that the contact state between the support mechanism 120 and the metal material 1 is normal.

  When the contact state abnormality detection unit 162 detects an abnormality in the contact state between the support mechanism 120 and the metal material 1 as a result of the determination, information indicating that fact is provided, for example, in an alarm device provided in the metal processing apparatus 10. Or provided to the above-described processing control unit or the like. According to the information, for example, an alarm is issued in the alarm device, or the processing is stopped by the processing control unit.

  The measurement of the reaction force and the frictional force in the support mechanism 120 may be performed at any time during the bending process, and the friction coefficient calculation unit 161 and the contact state abnormality detection unit 162 may perform the measurement according to the measurement timing. The friction coefficient calculation process and the contact state abnormality detection process may be performed as needed. That is, in this embodiment, an abnormality in the contact state can be detected at any time during the bending process.

  The functional configuration of the control device 160 shown in FIG. 1 has been described above with reference to FIG. As described above, according to the present embodiment, the friction coefficient between the support mechanism 120 and the metal material 1 is calculated based on the friction force and the processing reaction force measured by the support mechanism 120, and is calculated. Based on the friction coefficient, an abnormality in the contact state between the support mechanism 120 and the metal material 1 is detected. When an abnormality in the contact state is detected, processing is stopped or an alarm is given. Further, the detection of the abnormality in the contact state can be executed at any time during the machining. Therefore, it is possible to prevent the production of defective products due to an abnormality in the contact state between the support mechanism 120 and the metal material 1 and to improve the yield.

  In addition, the contact state abnormality detection unit 162 may detect the risk before the contact state abnormality actually occurs by appropriately setting a threshold value used for determining the contact state abnormality. For example, as the threshold value, a value close to the lower limit value and the upper limit value of the normal range is set although it is within the normal range of the friction coefficient. As a result, when a contact state abnormality is likely to occur, a predetermined action such as an alarm can be issued or processing can be stopped, so that the occurrence of a contact state abnormality can be prevented in advance. It becomes possible.

(4. Manufacturing method of metal material)
With reference to FIG. 7, the manufacturing method of the metal member which concerns on this embodiment is demonstrated. FIG. 7 is a flowchart showing an example of a processing procedure of the method for manufacturing a metal member according to the present embodiment. The processing procedure shown in FIG. 7 corresponds to the metal member manufacturing method executed in the metal processing apparatus 10 described above.

  Referring to FIG. 7, in the metal member manufacturing method according to the present embodiment, first, during the bending process on the metal material 1, the friction force and the reaction force are measured in the support mechanism 120 (step S <b> 101). In addition, as the said bending process, since the process similar to the process which concerns on general existing 3DQ is performed, description about the specific process sequence for performing the said bending process is abbreviate | omitted.

  Next, a friction coefficient between the support mechanism 120 and the metal material 1 is calculated based on the measured friction force and processing reaction force (step S103). Specifically, in step S103, the friction coefficient is obtained by dividing the measured friction force by the measured processing reaction force. Note that the processing shown in step S103 corresponds to the processing executed by the friction coefficient calculation unit 161 shown in FIG.

  Next, it is determined whether or not the calculated friction coefficient is within a normal range (step S105). In step S105, the calculated friction coefficient is stored in the friction coefficient DB 170 shown in FIG. 6, and the relationship between the product and the processed portion and the normal range of the friction coefficient between the support mechanism 120 and the metal material 1 is determined. It is judged whether or not the calculated friction coefficient is included in the normal range. Note that the process shown in step S105 corresponds to the process executed by the contact state abnormality detection unit 162 shown in FIG.

  When it is determined in step S105 that the friction coefficient is within a normal range, the contact state between the support mechanism 120 and the metal material 1 is normal, and no defect due to the abnormality in the contact state is generated. It is done. Therefore, in this case, the process returns to step S101 and waits until the frictional force and the machining reaction force are measured by the support mechanism 120 at the next measurement timing.

  On the other hand, if it is determined in step S105 that the coefficient of friction is outside the normal range, an abnormality has occurred in the contact state between the support mechanism 120 and the metal material 1, and if the processing is continued as it is, it is defective. Is considered to be at high risk. Accordingly, in this case, the process proceeds to step S107, and predetermined actions for suppressing the occurrence of bending defects such as processing stop or warning are executed.

  The metal member manufacturing method according to the present embodiment has been described above with reference to FIG.

  In order to confirm that the abnormality of the contact state between the support mechanism and the metal material can be detected by the method according to the present invention, the metal material is actually bent, and the frictional force and work reaction force at that time are calculated. It measured using the support mechanism which concerns on invention, Based on these measured values, the friction coefficient between the said support mechanism and metal material was computed. Specifically, as the metal processing apparatus, a metal processing apparatus corresponding to 3DQ having the same configuration as the metal processing apparatus 10 shown in FIG. 1 was used. Further, a support mechanism having the same configuration as the support mechanism 120 shown in FIGS. 2 and 3 was used.

Details of the processing conditions are as follows. Here, FIG. 8 is a figure for demonstrating the bending direction on the process conditions in an Example. In FIG. 8, the perspective view of the cross section of the metal material 1 used for experiment is shown.
(Processing conditions)
Metal material: Carbon steel pipe for mechanical structure Shape of metal material: rectangular cross section (long side length 46 mm, short side length 40 mm), length of about 1000 mm, wall thickness 1.6 mm
Bending direction: direction from one center to the other long side in one section (arrow direction shown in FIG. 8)

  In this experiment, as the state of the support mechanism, (1) the contact state between the support mechanism and the metal material is normal, and (2) the contact state between the support mechanism and the metal material becomes abnormal due to the occurrence of metal or the like. Assuming that the surface of the support mechanism that is in contact with the metal material is roughened, and (3) the contact state between the support mechanism and the metal material is not in contact with each other, and the contact state between them becomes abnormal. Each of these conditions (1) to (3) is prepared by measuring the friction force and the reaction force during the processing of the metal material, and calculating the friction coefficient. went. In condition (1), based on the result data, the contact state between the support mechanism and the metal material when no defective product actually occurs (that is, the surface state of the support mechanism and the support mechanism and the metal material) Etc.). Condition (2) and condition (3) simulate the case where the contact state is abnormal. In the case of condition (2), it is assumed that the friction coefficient is larger than the normal range. In the case of condition (3), it is assumed that the friction coefficient is smaller than the normal range.

  Specifically, in conditions (1) to (3), the surface of the guide shoe of the support member of the support mechanism that contacts the metal material is shown in Table 2 below. Specifically, in the conditions (1) and (3), the contact surface is not changed from the configuration of the guide shoe 124 according to the present embodiment shown in FIGS. On the other hand, under the condition (2), assuming that the contact state between the guide shoe and the metal material becomes abnormal due to the occurrence of metal or the like, the configuration of the guide shoe 124 according to the present embodiment shown in FIGS. On the other hand, a commercially available non-slip tape was affixed to the surface in contact with the metal material. In condition (3), the surface of the guide shoe 124 that contacts the metal material itself is not changed from that according to the present embodiment, but the contact state between the guide shoe and the metal material is not maintained. Assuming that became abnormal, the distance between the guide shoe and the metal material was made larger than the conditions (1) and (2).

  FIG. 9 and Table 3 below show the results of measuring the friction coefficient by the measurement mechanism provided on the support member. FIG. 9 is a graph showing the measurement result of the friction coefficient. In FIG. 9, the horizontal axis represents the time during processing, the vertical axis represents the measured value of the friction coefficient, and the relationship between the two is plotted. Table 3 summarizes the results shown in FIG. 9 as specific numerical values.

  As shown in FIG. 9 and Table 3, in the case of the condition (2) simulating the case where the contact state is abnormal, as compared with the condition (1) simulating the case where the contact state is normal, A larger coefficient of friction was calculated. Similarly, in the case of the condition (3) simulating the case where the contact state is abnormal, a smaller friction coefficient is calculated as expected compared to the condition (1) simulating the case where the contact state is normal. It was. The results show that the friction coefficient between the support mechanism and the metal material can be reliably detected by using the method according to the present invention, and the friction coefficient obtained by the method according to the present invention is the actual support mechanism. It shows that the contact state between the metal and the metal material can be appropriately expressed.

  Here, FIG. 10 is a photograph of the surface of the metal material after the actual bending under the condition (1). FIG. 11 is a photograph of the surface of the metal material after the actual bending process under the condition (2). 10 and 11 show an image of a region of the surface of the metal material that was in contact with the guide shoe during bending. Further, FIG. 12 is a photograph of the surface of the anti-slip tape on the guide shoe after actual bending under the condition (2). Similarly, FIG. 12 shows a photograph of an area of the surface of the non-slip tape that was in contact with the metal material during bending. Referring to FIG. 10, almost no wrinkles are formed on the surface of the metal material after the bending process under the condition (1). On the other hand, referring to FIG. 11, the surface of the metal material after the bending process is performed under the condition (2). It can be seen that there are wrinkles. Further, referring to FIG. 12, in condition (2), the surface of the portion of the anti-slip tape after bending that is in contact with the metal material (the portion located on the protruding guide shoe) is in contact with the metal material. It can be seen that it is worn. These results and the results shown in FIG. 9 and Table 3 use the method according to the present invention that the abnormality of the contact state between the guide shoe and the metal material can be accurately reproduced under the condition (2). This indicates that the abnormality of the contact state could be detected as a measured value of the friction coefficient.

  Thus, according to this example, it was confirmed that the friction coefficient reflecting the actual contact state can be detected by the method according to the present invention. Therefore, it is possible to detect the abnormality in the contact state more accurately by determining the abnormality in the contact state using the friction coefficient calculated by the method according to the present invention. In addition, as shown in FIG. 11, when an abnormality occurs in the contact state between the guide shoe and the metal material, wrinkles may occur in the metal material. That is, the result in this example also shows that the presence or absence of wrinkles in the metal material can be detected from the difference in friction coefficient by the method according to the present invention.

  Here, if the processing is continued despite the occurrence of an abnormality in the contact state, wrinkles may occur in the metal material as shown in FIG. 11, which may deteriorate the product quality. On the other hand, if the method according to the present invention is applied and a contact state abnormality can be detected more accurately during processing as in the present embodiment, the processing is interrupted and the guide shoe is replaced or repaired. By appropriately performing the above and maintaining a good contact state, the generation of defective products can be suppressed, and the yield can be improved. As described above, according to the present invention, the abnormality in the contact state can be detected more accurately, so that the effect of preventing the occurrence of wrinkles in the metal material and improving the yield can be expected.

  From the results shown in FIG. 9 and Table 3, if the normal range of the friction coefficient as shown in Table 1 in the machining in this experiment is defined, for example, the normal range is such that the friction coefficient is less than 0. It can be defined as a large and less than 0.3 range. That is, when it is going to apply the technique which concerns on this embodiment with respect to the product by which bending is performed on the process conditions similar to the said experiment, the contact state abnormality detection part 162 of the control apparatus 160 shown in FIG. If the measured friction coefficient is greater than 0 and less than 0.3, it is determined that the contact state is normal, and if the measured friction coefficient is 0 or 0.3 or more, the contact state is What is necessary is just to determine with it being abnormal.

(5. Supplement)
The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  For example, in the above-described embodiment, the case where the metal processing apparatus 10 is a processing apparatus corresponding to 3DQ has been described, but the present invention is not limited to such an example. The present invention can be applied to other processing devices as long as the processing device performs bending processing on the metal material while feeding the long metal material in the longitudinal direction.

1 Metal material (steel pipe)
DESCRIPTION OF SYMBOLS 10 Metal processing apparatus 110 Delivery mechanism 120 Support mechanism 121 Support member 122 Base material 123 Three component force load cell 124 Guide shoe 130 Heating mechanism 140 Cooling mechanism 150 Holding mechanism 160 Control apparatus 170 Friction coefficient DB

Claims (9)

A delivery mechanism for delivering a long metal material in the longitudinal direction;
A support mechanism for guiding and supporting the fed-out metal material at one site in the longitudinal direction;
A clamping mechanism that clamps the metal material at another part of the metal material and applies a bending load to the metal material;
With
The support mechanism measures a frictional force with the support mechanism when the metal material is fed out, and a reaction force acting on the support mechanism when the bending load is applied to the metal material. A measurement mechanism is provided,
Metal processing equipment. A friction coefficient calculator that calculates a friction coefficient between the support mechanism and the metal material based on the friction force and the processing reaction force measured by the support mechanism;
A contact state abnormality detection unit that detects an abnormality in a contact state between the support mechanism and the metal material based on the friction coefficient;
Further comprising
When the contact state abnormality detection unit detects an abnormality in the contact state, an alarm device issues an alarm, or a process for controlling the driving of the feeding mechanism and the clamping mechanism for bending the metal material The control unit stops processing the metal material.
The metal processing apparatus according to claim 1. The measurement mechanism of the support mechanism includes a guide shoe that supports the metal material during bending,
The portion of the guide shoe facing the metal material has an arc shape in a plane including the feed direction, and a linear shape in a plane orthogonal to the feed direction.
The metal processing apparatus according to claim 1 or 2. The measuring mechanism of the support mechanism is a load cell capable of detecting at least a force in a feeding direction of the metal material acting on the guide shoe and a force in a direction perpendicular to the feeding direction and in which the bending load is applied. Further including
The metal processing apparatus according to claim 3. A heating mechanism that is provided at a subsequent stage of the support mechanism and heats a part of the metal material in the longitudinal direction;
A cooling mechanism that is provided at a subsequent stage of the heating mechanism and cools a portion of the metal material heated by the heating mechanism;
Further comprising
Bending of the metal material is performed by applying a bending load to the portion heated by the heating mechanism of the metal material by the clamping mechanism.
The metal processing apparatus of any one of Claims 1-4. A feeding mechanism for feeding a long metal material in the longitudinal direction, a support mechanism for guiding and supporting the fed metal material in one part in the longitudinal direction, and sandwiching the metal material in another part of the metal material A metal member manufacturing method using a metal working device comprising a clamping mechanism for applying a bending load to a metal material,
The measurement mechanism provided in the support mechanism causes a frictional force with the support mechanism when the metal material is fed out, and a processing reaction that acts on the support mechanism when the bending load is applied to the metal material. Force is measured,
A method for producing a metal material. Calculate a friction coefficient between the support mechanism and the metal material based on the friction force and the processing reaction force measured by the support mechanism,
Detecting an abnormality in a contact state between the support mechanism and the metal material based on the friction coefficient;
When an abnormality in the contact state is detected, an alarm that the abnormality in the contact state has occurred is issued, or processing for the metal material is stopped,
The manufacturing method of the metal material of Claim 6. The measuring mechanism of the support mechanism includes a guide shoe that supports the metal material during bending, a force in the feed direction of the metal material that acts on the guide shoe, and a direction perpendicular to the feed direction and the bending load. A load cell capable of detecting at least a force in a direction in which the load is applied,
The portion of the guide shoe facing the metal material has an arc shape in a plane including the feed direction, and a linear shape in a plane orthogonal to the feed direction.
The manufacturing method of the metal material of Claim 6 or 7. The metal processing apparatus is
A heating mechanism that is provided at a subsequent stage of the support mechanism and heats a part of the metal material in the longitudinal direction;
A cooling mechanism that is provided at a subsequent stage of the heating mechanism and cools a portion of the metal material heated by the heating mechanism;
Further comprising
Bending of the metal material is performed by applying a bending load to the portion heated by the heating mechanism of the metal material by the clamping mechanism.
The manufacturing method of the metal material of any one of Claims 6-8.