JP2001138123A - Cutting device and cutting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting device and a cutting method capable of properly cutting a cut workpiece, by dispensing with position feedback control of a cutting blade, preventing an influence by a condition of the cut workpiece, and generating no damage to the cutting blade and no biting in the cut workpiece. SOLUTION: This cutting device, removing a protrusion on a surface of a cut workpiece, has a tool rest which can advance/retract relating to the cut workpiece, cutting blade held to the tool rest, and a drive mechanism advancing/ retracting the tool rest and controlling a pressure for pressing of the cutting blade to a surface of the cut workpiece, the cutting device, characterized by forming a negative rake angle of a rake face of the cutting blade relating to the cut workpiece, is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting device for removing projections and the like on the surface of a metal material such as steel, and more particularly to a cutting device suitable for deburring that does not require high precision processing. The present invention relates to an apparatus and a cutting method.

[0002]

2. Description of the Related Art Generally, in a cutting apparatus, a cutting blade is moved toward and away from a workpiece by a positioning mechanism or the like, and a cutting amount is determined by control means for driving the cutting blade. If the cutting blade itself is pressed against the workpiece without control, the cutting blade will cut into the workpiece. Therefore, position control of the cutting blade is important, and expensive position feedback control is required. For position control for determining the cutting amount, feedback control from a sensor for detecting the surface of the workpiece is used, or the position is stored in advance by teaching. For example, as disclosed in Japanese Patent Application Laid-Open No. 8-126939, a three-dimensional position is previously teach-ed, and a cutting reaction force is detected using a force sensor on a cutting blade as feedback control, and the force control is taken into consideration. For controlling the cutting position of the cutting blade.

[0003] As a cutting device used in a continuous rolling mill for strip steel, there is a deburring device. The continuous rolling equipment for strip steel continuously casts and directly feeds, or welds coarse steel slabs such as billets heated in a heating furnace by a welding machine and continuously feeds them to a rolling mill to improve productivity. Since the billet and the like have a large cross-sectional area, welding is performed using flash butt welding or the like. At this time, a burr-like burr occurs at the weld between the billets, which is about 10 mm in height and 3 mm in foot width.
It extends to more than 0 mm. If these projections remain, the steel material is damaged during rolling, and the joints are damaged, and the rolls are damaged. Therefore, it is necessary to remove burrs by a deburring device after welding. −112
No. 593 discloses an example using a cutting device using a cutting blade.

However, when removing burrs generated when a billet or the like is welded in a continuous rolling mill for strip steel, unevenness in the size of the projections, fluctuation in the size of the material to be cut, and a step at the joint portion of the joining material are required. There has been a problem that the load applied to the cutting blade fluctuates, sometimes causing an excessive load to damage the cutting blade, or the cutting blade bites into the workpiece. FIG. 4 shows an example of deburring using a conventional cutting blade. When there is a step before and after the projection (burr) 2 as in the workpiece 1 in FIG. 4, the sharp cutting blade 4 whose rake face (cutting edge face) 40 has a positive rake angle θ It cuts into the workpiece 1 and the cutting blade 4 cannot be retracted.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, eliminates the need for position feedback control of the cutting blade, is not affected by the state of the work material, and is free from damage to the cutting blade and damage to the work material. It is an object of the present invention to provide a cutting device and a cutting method capable of appropriately cutting a workpiece without causing bite.

[0006]

The above object is achieved by the following invention. The first invention of the present invention relates to a cutting device for removing a projection on a surface of a workpiece, a tool rest capable of moving back and forth with respect to the workpiece, a cutting blade held by the tool rest, and moving the tool rest forward and backward. And a drive mechanism for controlling the pressing pressure of the cutting blade against the surface of the workpiece, wherein the rake face of the cutting blade forms a negative rake angle with respect to the workpiece. Cutting equipment.

[0007] The second invention of the present invention is the cutting apparatus according to claim 1, wherein the ridge line between the rake face of the cutting blade and the flank of the cutting blade is circular.

A third aspect of the present invention is the cutting device according to the second aspect of the present invention, wherein the cutting blade is rotatably mounted on the tool rest.

According to a fourth aspect of the present invention, there is provided a cutting method using the cutting device according to the first, second, or third aspect of the present invention, wherein a pressure for pressing the cutting blade against the surface of the workpiece by the moving mechanism during the cutting. This is a cutting method characterized by controlling.

[0010] In a fifth aspect of the present invention, the pressure control mechanism has a pressure adjusting valve, and after the cutting blade is pressed against the workpiece, before the projection on the surface of the workpiece reaches the cutting blade, the pressure adjusting mechanism is provided. The cutting method according to the fourth aspect of the present invention, wherein the cutting blade is pressed against the surface of the material to be cut with a constant pressure by using a valve to control a cutting amount of the cutting blade.

In the sixth aspect of the present invention, after the cutting blade is pressed against the surface of the workpiece, the moving mechanism stops moving forward and backward, and the pressure for pressing the cutting blade against the surface of the workpiece becomes equal to or higher than a set pressure. The cutting method according to the fourth aspect of the present invention, wherein the cutting amount of the cutting blade is controlled by retracting the cutting blade from the surface of the workpiece only when the cutting is performed.

[0012] The seventh invention of the present invention is characterized in that in the continuous rolling equipment for strip steel, it is arranged in a post-welding process in order to remove welding burrs generated by welding, wherein the first invention to the third invention is characterized in that: A cutting device according to any one of the preceding claims.

[0013]

1 and 2 show an embodiment of a cutting device according to the present invention. FIG. 1 is a side view showing the entire cutting device, and FIG. 2 is a side view showing a main part of the cutting device. It is.
FIGS. 1 and 2 show an example in which there is a step in a portion of a projection 2 (such as a burr) of the workpiece 1, and shows a state in which the cutting device and the workpiece 1 relatively move.

The cutting device according to the present invention comprises a tool rest 3 capable of moving forward and backward with respect to the workpiece 1, a cutting blade 4 held by the tool rest 3, and a tool for moving the tool rest 3 forward and backward, and And a drive mechanism A for controlling the pressing pressure on the surface of the workpiece 1.

In the drawing, reference numeral 9 denotes a gantry arranged above the material to be cut, 5 denotes a turret holder which is mounted on the gantry 9 so as to be vertically movable (elevated), and the turret 3 is a turret. By being held by the holder 5, it is arranged to be movable in the vertical direction, that is, to be able to advance and retreat with respect to the workpiece. The gantry 9 has an elevating guide 6 in the vertical direction, and the tool rest holder 5 is provided so as to elevate and lower along the elevating guide 6.

The tool rest 3 has a holding shaft 7 at its lower end for holding the cutting blade 4, and has flange-shaped stoppers 26, 27 at the upper end and at the base end of the holding shaft 7, respectively.
have. A cutting blade 4 is provided at the lower end of the holding shaft 7.
Is provided with a flange-shaped blade stopper 8 for preventing falling off.

On the other hand, in the up-down direction of the tool post holder 5, there is provided a through hole 28 for inserting the tool post. The tool post 3 is inserted into the fitting hole 28 and the stopper is inserted. The portions 26 and 27 are held by the tool post holder 5 by engaging the upper and lower ends of the tool post holder 5.

The insertion hole 28 is formed so as to be inclined forward by an appropriate angle toward the cutting portion of the workpiece 1. Therefore, the tool rest 3 held by the fitting insertion hole 28 is also inclined toward the cutting portion of the workpiece 1. At an appropriate angle. The inclination of the tool post 3 gives a clearance angle to the clearance surface 41 corresponding to the bottom surface of the cutting blade 4.

The cutting blade 4 has a rake face 40 and a flank face 41.
Is a cutting blade having a circular edge line (that is, a cutting edge portion), and in the present embodiment, is constituted by a ring-shaped cutting blade having an appropriate thickness. The lower peripheral surface of the cutting blade 4 is a tapered surface whose diameter is reduced downward, and this surface constitutes the rake surface 40. The ridge line between the rake face 40 and the flank face 41 is circular.

The cutting blade 4 is rotatably mounted on the holding shaft 7 of the tool post 3 through a mounting hole 42 penetrating through the center thereof, and is raked in the state held by the tool post 3 in this manner. The rake face formed by the face 40 forms a negative rake angle θ. The formation of the negative rake angle on the rake face as described above is a major feature of the apparatus of the present invention, whereby the cutting blade can be pressed against the workpiece without performing position feedback control as in the conventional apparatus. The blade can also appropriately prevent biting into the workpiece and can be cut without position feedback control. In general, if the rake face of the cutting blade is set at a negative rake angle, the load increases, the sharpness becomes poor, and the surface roughness increases. Therefore, the rake face of the cutting blade for other uses also has a negative rake angle. It is not often considered that the cutting amount is small, or the cutting of hot material such as hot billet deburring as the main object of the present invention (in this case, even if the cutting amount is large) In such cases, it was found that good cutting can be performed even if a negative rake angle is formed on the rake face. When a cutting blade having a negative rake angle is used, the cutting edge angle of the cutting blade increases, so that the strength of the cutting blade increases and breakage hardly occurs. Especially when a circular cutting blade is used, the circular arc is in contact with the workpiece, so the bite into the workpiece,
Less likely to happen.

The clearance angle β is given to the flank 41 of the cutting blade 4 by the inclination of the tool rest 3 described above. The mounting hole 42 has a step formed by increasing the diameter of the lower end thereof, and the stopper 8 at the lower end of the holding shaft 7 is engaged with the step, whereby the cutting blade 4 is moved from the holding shaft 7. Dropout is prevented.

In the present invention, a rake angle of 0 ° is also effective.
The negative rake angle is set to about 0 ° to −30 °, and most preferably −10 ° to −20 °. If the negative angle is −
If the angle exceeds 30 °, the cutting load increases significantly, which is not preferable.

The structure of the cutting blade 4 is not limited to the present embodiment. For example, a structure in which the cutting blade 4 is fixed to the tool rest 3, a rake surface of the cutting blade 4 and a flank of the flank of the cutting blade 4 are provided. Although an appropriate structure such as a non-circular structure having a non-circular ridge line (that is, a blade edge portion) can be adopted, the cutting blade 4 is formed in a ring shape having an appropriate thickness as in the present embodiment, and the cutting blade 4 is a cutting tool. The following advantages can be obtained by adopting a structure that is rotatably mounted on the holding shaft 7 of the base 3.

First, the cutting blade 4 is formed in a ring shape having an appropriate thickness, and the ridge line (that is, the cutting edge) between the rake face 40 and the flank 41 is made circular, so that Therefore, there is an advantage that the cutting edge portion hardly bites into the workpiece to be cut because the arc-shaped cutting edge portion comes into contact. In addition, since the ring-shaped cutting blade 4 is rotatable with respect to the tool rest 3, the cutting blade 4 rotates freely regardless of cutting or cutting, so that the cutting edge that comes into contact with the material to be cut is naturally formed. And there is a great advantage that the frequency of replacement of the cutting blade can be reduced.

In the present embodiment, the tool rest 3 is attached with an inclination to the tool rest holder 5 in order to provide the clearance angle β of the cutting blade 4. The clearance angle β of the cutting blade 4 may be formed by giving an inclination. Also, the holding shaft 7
For example, a bearing can also be used as a mounting structure of the cutting blade 4 with respect to.

The drive mechanism A comprises a hydraulic cylinder 10 in this embodiment. This hydraulic cylinder 1
Reference numeral 0 denotes a tool post 3 having a main body fixed to the gantry 9 and a piston rod 11 connected to an upper end of the tool post 3 via a pin.
And the tool rest 3 is moved up and down (up and down), that is, moved forward and backward with respect to the workpiece 1. The drive mechanism A not only moves the tool rest 3 forward and backward, but also has a function of controlling the pressing pressure of the cutting blade 4 against the surface of the workpiece.

The hydraulic system of the hydraulic cylinder 10 includes a hydraulic pump (not shown), a main valve 12, which is an electromagnetic switching valve, a P port 13, an H port 14, an R port 15, a T port 16,
It comprises a pressure regulating valve 17, a tank (not shown) and the like. In this hydraulic system, the oil from the hydraulic pump is
2 to the P port 13 of the cutting blade 4
During the forward operation, the oil is sent from the H port 14 of the electromagnetic switching valve to the head side of the hydraulic cylinder 10, and the spilled oil from the hydraulic cylinder 10 flows from the R port 15 through the main valve 12 to the T port 1.
From 6 is returned to a tank (not shown). On the other hand, when the cutting blade 4 leaves the workpiece 1, the P port 1
3 is sent from the R port 15 of the main valve 12 to the rod side of the hydraulic cylinder 10,
4 through the main valve 12 to return from the T port 16 to the tank. With such a mechanism, first, the cutting blade 4 is brought into contact with the target workpiece 1. The pressure regulating valve 17 is used for pressure control described later.

The drive mechanism A can use any other hydraulic cylinder (for example, an air cylinder) other than the hydraulic cylinder.

Referring to the other structure shown in the figure, reference numeral 21 denotes a base for supporting the entire apparatus, and the gantry 9 is supported on the base 21 by a support frame. Reference numeral 22 denotes a workpiece support / movement mechanism provided on the base 21 for supporting the workpiece and moving the workpiece relative to the cutting device. The mechanism 22 is provided on the base 21 below the cutting blade 4. Transfer table 2 provided to be movable in the horizontal direction
3, a clamp 24 for fixing the workpiece to the transfer table 23, and a hydraulic cylinder 25 for moving the transfer table, the main body of which is fixed on the base 21 and the cylinder rod of which is connected to the transfer table 23. It is composed of The electromagnetic switching valve 29 is a hydraulic device that switches or branches the hydraulic pressure from the pump to the hydraulic cylinder 10 for raising and lowering the cutting blade and the hydraulic cylinder 25 for moving the transfer table.

FIG. 3 shows another embodiment of the cutting apparatus of the present invention, and shows one embodiment in which the apparatus of the present invention is applied to a deburring apparatus used in a continuous rolling mill for strip steel. , A welding machine and a rolling mill are not shown).

In this cutting device, the main part of the cutting device according to one embodiment of the present invention is provided in the vertical direction of the strip steel rolling line. The function is also arranged. In the continuous rolling equipment, since the welding billet 33 as the workpiece is moved, a mechanism for moving the workpiece in the line direction is not required. Since other configurations are the same as those of the embodiment shown in FIGS. 1 and 2, the same reference numerals are given and the detailed description is omitted.

According to such an apparatus, a measuring roll 32 having an encoder is attached to a welding billet 33 having a burr (projection) 34 at a welding portion, which is sent from a welding machine on a transport roller 31. , The passing position of the burr 34 is detected, and when the burr 34 approaches the cutting device, the cutting blade 4 is brought into contact with the surface of the welding billet 33 so that the burr 34
To cut. Since cutting is performed by the pulling force of the rolling mill, a driving source for cutting is not required. At this time billet 3
Even if there is a step in the welded portion 3, deburring can be performed reliably by setting the pressure to press the cutting blade 4 against the surface of the billet 33 with a constant pressing pressure so as to follow the surface of the billet 33. . In addition, since a rotatable circular cutting blade is used as the cutting blade 4, even if the equipment is operated for a long time in continuous rolling, the rake face is rotated and renewed naturally, and the frequency of replacement of the cutting blade is reduced. It is suitable for continuous rolling equipment.

It is of course possible to cut the burr 34 by moving the cutting device itself, for example, by incorporating the cutting device into a traveling welding machine, and the cutting device and the workpiece are relatively moved. If cutting can be performed, there is no problem even if both move. In any case of the present embodiment, the workpiece and the cutting blade only need to move relatively, and it is not necessary to fix one of them.

Next, a method of using the above-described cutting device and a preferable cutting method will be described.

In order to remove burrs and the like on the billet surface, it is necessary to move the cutting blade to the surface of the material to be cut, and the approach and retreat of the cutting blade are performed by a hydraulic actuator such as hydraulic pressure or water pressure, or by an empty actuator. This is performed by moving the tool rest on which the cutting blade is mounted by a gas pressure actuator such as pressure. Usually, position feedback control is used here,
In the present invention, by performing this by pressure control of a hydraulic cylinder or the like, complicated position control is eliminated. That is, the contact pressure of the cutting blade with respect to the billet surface is set by a pressure detector such as a pressure sensor or a pressure switch, and the cutting blade is stopped when it comes into contact with the surface. If the set pressure of the pressure detector is set to a sufficiently small pressure, no unnecessary cutting force is generated in the workpiece.

However, a surge pressure is instantaneously generated at the start of driving of the hydraulic cylinder, and the pressure detector may be actuated by this pressure. It is important to use a sensor or the like to apply a filter that does not detect the pressure at the start of cylinder operation until the timer is operating or the limit sensor is hit. It is also effective to start the drive at the center of the cylinder so that the surge pressure is not generated as much as possible. In this case, the filter can be omitted.

After the cutting blade contacts the surface of the workpiece,
The amount of cutting is controlled by controlling the pressure of the actuator. Two types of pressure control are conceivable. One method is to press the cutting blade against the material with a constant pressing pressure after the cutting blade contacts the surface of the workpiece, and the other is to determine the position of the cutting blade at the position where the cutting blade contacts the surface of the workpiece. It is a method of fixing.

In the former method, it is possible to surely cut with a fixed amount of cutting. For example, even when the size of the material to be cut is small, the hydraulic cylinder is driven so that the cutting amount is constant. Is possible. In this method, after the cutting blade is pressed against the material to be cut by the actuator, the cutting blade such as a protrusion on the surface of the material to be cut reaches the cutting blade before the cutting portion reaches the cutting blade. A constant pressure is applied to the surface to control the cutting amount of the cutting blade. After switching to the constant pressing pressure control, the hydraulic oil is continuously supplied to the cylinder extension side by the hydraulic switching valve (main valve). At this time, excess pressure is returned to the tank by adjusting the pressure of the pressure adjusting valve attached to the cylinder extension side, so that the cylinder is continuously pressurized at a constant pressure. The pressure regulating valve is easy to adjust and does not require any special electrical or software control.
Inexpensive and reliable cutting is possible.

The latter method is a method of removing an amount that can be cut at the position on the basis of the surface of the material to be cut. Therefore, it is possible to cut only a portion higher than the reference surface without performing unnecessary cutting. In this case, the cutting blade maintains a constant height regardless of where the surface of the workpiece is low. In this method, after the cutting blade is pressed against the work material by the actuator, from the time of switching to the position fixing control, the main valve of the hydraulic pressure switching that drives the cylinder in the direction in which the cutting blade retracts from the work material is locked, Fix the cutting blade. When a pressure smaller than the pressure adjustment value of the pressure adjustment valve attached to the cylinder extension side is applied to the cutting blade, the position of the cutting blade is maintained, and only when the specified pressure or more is applied to the cutting blade, Drain the working fluid or gas and return the excess pressure to the tank to retreat the cutting blade from the surface of the material to be cut, prevent the cutting blade from biting into the material to be cut, and control the cutting amount of the cutting blade I do.

The cutting load applied to the cutting blade mainly acts in the traveling direction of the cutting blade. However, since the cutting blade has a negative rake angle, a cutting load component acts on the actuator which operates in the approaching and retracting directions. Pressure control on the object to be cut becomes easy. In addition, the pressure rises faster, and the responsiveness of pressure control to a sudden load change is improved.

[0041]

According to the present invention, since a cutting blade having a negative rake angle with respect to the material to be cut is used, the cutting edge angle of the cutting blade is increased, so that the strength of the cutting blade is increased and breakage hardly occurs. The cutting blade is less likely to bite into the cutting material. Especially when a circular cutting blade is used, the circular arc is in contact with the workpiece, so the bite into the workpiece,
Less likely to happen. Further, the pressure control on the object to be cut is facilitated, the pressure rises quickly, and the responsiveness of the pressure control to a sudden load change is improved.

Further, since the pressure control is performed without using the position feedback control, the pressure regulating valve for performing the pressure control is easy to adjust and is inexpensive because it does not require special electrical and software control. .

[Brief description of the drawings]

FIG. 1 is a side view showing an entire cutting apparatus according to an embodiment of the present invention.

FIG. 2 is a side view showing a main part of a cutting device according to an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a cutting device applied to a deburring device of a continuous rolling facility, which is another embodiment of the present invention.

FIG. 4 is an explanatory view when a conventional cutting blade having a positive rake angle is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Material to be cut 2 Projection 3 Turret 4 Cutting blade 5 Turret holder 6 Elevation guide 7 Holding shaft 8 Blade stopper 9 Mounting stand 10 Hydraulic cylinder 11 Piston rod 12 Main valve 13 P port 14 H port 15 R port 16 T port 17 Pressure adjusting valve 21 Base 22 Workpiece support / movement mechanism 23 Transfer table 24 Clamp 25 Hydraulic cylinder 26 Stopper 27 Stopper 28 Fitting hole 29 Electromagnetic switching valve 31 Transfer roller 32 Transfer roller and measuring ring roll 33 Weld billet 34 Burr 40 Rake surface 41 Relief surface 42 Mounting hole A Drive mechanism β Relief angle θ Squeeze angle

Claims (7)

[Claims] 1. A cutting device for removing projections on a surface of a workpiece, a tool rest capable of moving back and forth with respect to the workpiece.
A cutting blade held by the tool post, and a drive mechanism for moving the tool post forward and backward and controlling a pressing pressure of the cutting blade against the surface of the workpiece, wherein the rake face of the cutting blade is A cutting device characterized by forming a negative rake angle with respect to. 2. The cutting device according to claim 1, wherein the ridge line between the rake face of the cutting blade and the flank of the cutting blade is circular. 3. The cutting apparatus according to claim 2, wherein the cutting blade is rotatably mounted on the tool post. 4. A cutting method using the cutting device according to claim 1, wherein a pressure for pressing a cutting blade against a surface of a workpiece by a moving mechanism is controlled during cutting. And cutting method. 5. The pressure control mechanism has a pressure regulating valve, and after pressing the cutting blade against the workpiece, before the projection on the surface of the workpiece reaches the cutting blade, using the pressure regulating valve. The cutting method according to claim 4, wherein the cutting blade is pressed against the surface of the material to be cut with a constant pressure, and a cutting amount of the cutting blade is controlled. 6. After pressing the cutting blade against the surface of the workpiece,
Stop the reciprocation of the moving mechanism, only when the pressure pressing the cutting blade against the surface of the workpiece is equal to or higher than a set pressure,
By retracting the cutting blade from the surface of the workpiece,
The cutting method according to claim 4, wherein a cutting amount of the cutting blade is controlled. 7. The method according to claim 1, wherein the continuous rolling equipment for strip steel is disposed in a post-welding process to remove welding burrs generated by welding. Cutting equipment.