JP4577866B2 - Drilling apparatus and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a drilling apparatus and method for prolonging the life of a drill, shortening the machining time, and cutting chips quickly and easily.
[0002]
[Prior art]
[0003]
2. Description of the Related Art Conventionally, a drilling apparatus has a machining head 50 equipped with a drill 51 that is rotated by a motor M (FIG. 11). Process the hole Q.
[0004]
In such a drilling apparatus, if the chips generated during the cutting process are left as they are, problems such as an obstacle to the cutting process occur. Therefore, the chips are conventionally divided.
[0005]
In this case, there are two methods shown in FIGS. 11 and 12 for dividing the chips.
[0006]
In the method shown in FIG. 11, the machining head 50 is retracted during the cutting process, and the cutting edge K of the drill 51 is once separated from the workpiece W to divide the chips K.
[0007]
That is, in FIG. 11, for example, after cutting is started at t1, at t2 during cutting, the cutting edge of the drill 51 that rotates by rotating the processing head 50 away from the bottom of the hole Q being processed is separated from the chip K. At t3, the machining head 50 is advanced at a high speed, and at t4, the rotating drill 51 is abutted against the bottom of the hole Q to perform cutting again.
[0008]
In the method of FIG. 12, the chip K is divided by temporarily stopping the machining head 50 in the workpiece W during the cutting process.
[0009]
That is, in FIG. 12, for example, after cutting is started at t1, the cutting head 50 is temporarily stopped at t2 during cutting, thereby pushing the cutting edge of the rotating drill 51 into the bottom of the hole Q being processed. The chip K is divided while being applied, and at t3, the machining head 50 is advanced to perform cutting again.
[0010]
[Problems to be solved by the invention]
[0011]
However, the methods shown in FIGS. 11 and 12 have the following problems.
[0012]
(1) Problems with the method of FIG.
In the case of FIG. 11, as described above, the machining head 2 is retracted (for example, t2 to t3 in FIG.
[0013]
For this reason, chips K may be caught between the drill 51 and the workpiece W, and the drill 51 moves forward at a high speed after retreating (for example, t3 to t4 in FIG. 11) and hits the bottom of the hole Q being processed. The load increases rapidly.
[0014]
As a result, an impact is applied to the drill 51 and the life of the drill 51 is shortened.
[0015]
In the case of FIG. 11, the machining head 50 is temporarily retracted (t2 to t3 in FIG. 11) and then advanced at a high speed (t3 to t4 in FIG. 11) to reciprocate the drill 1 against the bottom of the hole Q. Is done.
[0016]
As a result, due to such extra reciprocating motion, the processing time becomes longer and the efficiency is lowered.
[0017]
(2) Problems with the method of FIG.
In the case of FIG. 12, as described above, the machining head 50 is temporarily stopped during the cutting process, so that the chips K are divided while the cutting edge of the rotating drill 51 is abutted against the bottom of the hole Q being machined. To do.
[0018]
Therefore, unlike the case of FIG. 11, the life of the drill 51 is not shortened and the processing time is not lengthened.
[0019]
However, even if the machining head 50 is temporarily stopped during cutting, the machining head 50 side or the workpiece W side may bend due to the cutting load.
[0020]
For example, when the workpiece W is an H-shaped steel, the rigidity is smaller than that of the mug material, and therefore, the workpiece W is easily bent due to a cutting load.
[0021]
As a result, the rotating drill 51 may cut the workpiece W while it abuts against the bottom of the hole Q being processed due to the deflection of the workpiece W.
[0022]
That is, conventionally, it takes a long time to make the relative speed between the drill 1 and the work W zero due to the bending of the machining head 2 side or the work W side, so that until the relative speed becomes zero, Chips may be thinly connected and cannot be divided.
[0023]
An object of the present invention is to increase the life of a drill, shorten the processing time, and sever a chip quickly and easily in a drilling apparatus.
[0024]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides:
A machining head 2 provided with a rotatable drill 1; a hydraulic cylinder 4 for moving the machining head 2; and an elastic member 3 fitted between the hydraulic cylinder 4 and the machining head 2;The hydraulic circuit that drives the hydraulic cylinder 4 includes a direction switching circuit 7 that performs switching to move the hydraulic cylinder 4 forward or backward,
The restoring force of the elastic member 3 is smaller than the thrust of the hydraulic cylinder 4, and the direction switching circuit 7 is switched to the reverse mode (FIG. 6) while the elastic member 3 is contracted during drilling. When the hydraulic cylinder 4 is stopped,With the rotating drill 1 stopped against the workpiece W, the hydraulic cylinder 4Piston rod 5A drilling device characterized by retreating with respect to the machining head 2 by the restoring force of the elastic member 3;
A drilling method using the above drilling device,
(1)
The hydraulic cylinder 4 is moved forward at a cutting feed speed in a state where the hydraulic cylinder 4 is in contact with the machining head 2, and the workpiece 1 is moved by the rotating drill 1.DrillingAnd
(2) TheWhen the hydraulic cylinder 4 is stopped by switching the direction switching circuit 7 to the reverse mode (FIG. 6) while the elastic member 3 is contracted during the drilling process, the rotating drill 1 is set to the workpiece W. The piston rod 5 of the hydraulic cylinder 4 retreats with respect to the machining head 2 by the restoring force of the elastic member 3 in a state of being stopped by hitting.                    In addition, the cutting means K is cut in a state where the rotating drill 1 is stopped against the workpiece W, and the above-described (1) and (2) operations are repeated. ing.
[0025]
According to the configuration of the present invention, since the drill 1 can be divided without separating the drill 1 from the workpiece W (FIG. 3B), the chips are sandwiched between the drill 1 and the workpiece W, The drill 1 never comes into contact with the workpiece W again, so that the life of the drill 1 is extended and the machining time is shortened. Further, the elastic member 3 absorbs the bending of the machining head 2 side and the workpiece W side due to the machining load. As a result, the relative speed between the drill 1 and the workpiece W is quickly reduced to zero, and chips can be divided quickly and easily.
[0026]
For this reason, according to the present invention, in the drilling device, it is possible to prolong the life of the drill, shorten the processing time, and sever the chips quickly and easily.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the accompanying drawings by embodiments.
FIG. 1 is an overall view showing an embodiment of the present invention.
[0028]
The drilling apparatus shown in FIG. 1 has a machining head 2 to which a rotatable drill 1 is attached and a hydraulic cylinder 4 that moves the machining head 2.
[0029]
That is, the drilling device (FIGS. 8 and 9) is a device that generally cuts the workpiece W and performs drilling. As will be described later, for example, an H-shaped steel web WB and left and right flanges LF, Perform RF drilling.
[0030]
Among these, FIG. 1 shows a drill 1 for drilling holes in the left and right flanges LF and RF of the H-shaped steel (FIG. 8).
[0031]
The machining head 2 of this drill 1 has a Y-axis guide21The elastic member 3 is inserted between the machining head 2 and the piston rod 5 of the hydraulic cylinder 4, and examples of the elastic member 3 include a coil spring, an air cushion, and rubber. .
[0032]
With this configuration, at the time of cutting feed (FIG. 3A), the piston rod 5 of the hydraulic cylinder 4 abuts the machining head 2, and the machining head 2 is in contact with the Y-axis guide.21The workpiece W is advanced with the cutting feed speed, and the workpiece W is cut by the drill 1 rotated by the motor M2, and the hole Q is made.
[0033]
During this time, the elastic member 3 contracts to store energy therein.
[0034]
However, when the hydraulic cylinder 4 shuts off the rod-side hydraulic chamber 4B during the cutting process and stops the head-side hydraulic chamber 4A by communicating with the oil tank 13 (FIG. 6), the workpiece W side is moved to a movable vise 24 described later. 25 (FIG. 9) and the fixed vices 22 and 23, the elastic member 3 expands by releasing energy to the piston rod 5 side opposite to the workpiece W side (FIG. 3 (B)). .
[0035]
As a result, the piston rod 5 moves backward with respect to the machining head 2 due to the restoring force of the elastic member 3, and a gap δ is formed between the piston rod 5 and the machining head 2, and the drill 1 remains in contact with the workpiece W. Stop.
[0036]
At this time, the stretched elastic member 3 absorbs the bending of the machining head 2 side and the workpiece W side, so that the drill 1 can be stopped suddenly from the cutting feed with respect to the workpiece W. However, the chip K can be divided quickly and easily.
[0037]
In this case, as will be described later, the rotating drill 1 hits the workpiece W from the time when the hydraulic cylinder 4 starts to retract until it contacts the machining head 2 (for example, t4 to t5 to t6 in FIG. 2). The chips K are cut off while stopping.
[0038]
Further, the force with which the rotating drill 1 is abutted against the workpiece W is a restoring force of the elastic member 3 and is slight compared with the thrust of the hydraulic cylinder 4, and therefore the drill 1 is in a state where the drill 1 is stopped. The cutting process is not performed.
[0039]
In this way, the hydraulic cylinder 4 and the machining head 2 perform the step feed operation by repeating operations such as cutting and cutting of the chips K by the stopped drill 1 (FIG. 3A) (FIG. 3B). (E.g., t3 to t4, t4 to t5 to t6 in FIG. 2)
[0040]
On the other hand, the hydraulic circuit for driving the hydraulic cylinder 4 (FIG. 1) is composed of a direction switching circuit 7, a flow rate control circuit 8, and a feed switching circuit 9, as shown.
[0041]
The direction switching circuit 7 switches between forward movement (for example, cutting feed in FIG. 5) or backward movement (for example, backward movement during cutting feed in FIG. 6) of the hydraulic cylinder 4, and is constituted by, for example, a 4-port 3-position electromagnetic valve 7A. A hydraulic pump 11 driven by a motor M is connected to P, and an oil tank 13 is connected to the port T.
[0042]
The flow rate control circuit 8 controls the flow rate of hydraulic oil discharged from the hydraulic cylinder 4 in the case of cutting feed (FIG. 5), and the piston rod 5 of the hydraulic cylinder 4 has a flow rate set by the flow rate control circuit 8. It moves forward at a prescribed cutting feed rate, and is composed of, for example, a flow rate adjusting valve 8A and a check valve 8B (FIG. 1) connected in series.
[0043]
The feed switching circuit 9 switches from the rapid feed (FIG. 4) to the cutting feed (FIG. 5) of the hydraulic cylinder 4 or from the cut feed (FIG. 5) to the rapid return after penetrating the workpiece W (FIG. 7). For example, it is constituted by a 2-port 2-position electromagnetic valve 9A.
[0044]
With this configuration, for example, during cutting (eg, t3 to t4 in FIG. 2), the solenoid SOL (1) of the solenoid valve 7A constituting the direction switching circuit 7 is on, the solenoid SOL (2) is off, and the feed switching circuit 9 The solenoid SOL <3> of the electromagnetic valve 9 </ b> A that constitutes is turned off.
[0045]
As a result, the solenoid valve 7A (FIG. 1) is in the position a and the ports A and P, and the ports B and T are conducted, and the solenoid valve 9A is in the position d and the ports C and D are shut off. The hydraulic circuit is in the cutting feed mode (FIG. 5).
[0046]
Accordingly, the hydraulic oil in the oil tank 13 passes through the hydraulic filter 12, is then pumped up by the hydraulic pump 11 driven by the motor M, passes through the ports P and A of the direction switching circuit 7 (FIG. 5), and passes through the head of the hydraulic cylinder 4. By entering the side hydraulic chamber 4A, the machining head 2 is advanced at the cutting feed speed via the piston rod 5, and the hydraulic oil discharged from the rod side hydraulic chamber 4B of the hydraulic cylinder 4 at this time is supplied to the flow control circuit 8 And return to the oil tank 13.
[0047]
In this state, when a certain time elapses during cutting (for example, t4 in FIG. 2), the solenoid valve 9A of the feed switching circuit 9 is left as it is, and the solenoid SOL (1) constituting the direction switching circuit 7 is turned off. Switch SOL (2) on.
[0048]
As a result, the solenoid valve 7A (FIG. 1) is in the position c, the ports A and T, the ports B and P are conducted, the rod side hydraulic chamber 4B of the hydraulic cylinder 4 is shut off, and the head side hydraulic chamber 4A is The hydraulic circuit communicates with the oil tank 13 and switches to the reverse mode (FIG. 6).
[0049]
Accordingly, the hydraulic cylinder 4 is stopped, and as described above, the piston rod 5 is now retracted by the restoring force of the elastic member 3, and at this time, the hydraulic oil in the head side hydraulic chamber 4A of the hydraulic cylinder 4 is supplied to the oil tank 13 Return to.
[0050]
Then, after a lapse of a certain time (for example, t5 in FIG. 2), the solenoid valve 9A of the direction switching circuit 7 is turned on while the solenoid valve 9A of the feed switching circuit 9 is left, and the solenoid SOL2 is turned on. When switched off, the solenoid valve 7A switches to the position a (FIG. 1) and enters the cutting feed mode again (FIG. 5). After the piston rod 5 moves forward and contacts the machining head 2 (t6 in FIG. 2), The workpiece W is cut by the drill 1 that the processing head 2 advances and rotates at the cutting feed speed, and the hole Q is reworked.
[0051]
In this case, as described above, the rotating drill 1 is in a period from when the piston rod 5 of the hydraulic cylinder 4 starts to retract until it contacts the machining head 2 (for example, t4 to t5 to t6 in FIG. 2). The swarf K is divided while it stops at the work W.
[0052]
Further, before cutting starts, the cutting edge of the drill 1 moves forward from a state where it is separated from the workpiece W, and after a certain time has elapsed after it hits the workpiece W (t0 to t2 in FIG. 2), the direction is switched. In the circuit 7 (FIG. 1), the solenoid SOL (1) of the solenoid valve 7A is on, SOL (2) is off, and the solenoid SOL (3) of the solenoid valve 9A of the feed switching circuit 9 is on. This is a fast-forward mode (FIG. 4).
[0053]
Further, when the drill 1 penetrates the workpiece W (t10 in FIG. 2) and the cutting process is completed, the solenoid SOL (1) of the electromagnetic valve 7A in the direction switching circuit (FIG. 1) is turned off and SOL (2). ▼ is turned on, the solenoid SOL (3) of the electromagnetic valve 9A of the feed switching circuit 9 is turned on, and the hydraulic circuit enters the fast return mode (FIG. 7).
[0054]
On the other hand, the NC device 10 in FIG. 1 controls the entire drilling device (FIGS. 8 and 9) including a hydraulic circuit such as the direction switching circuit 7.
[0055]
8 and 9 are diagrams showing a drilling apparatus to which the present invention is applied.
[0056]
The drilling device has a portal frame 14 erected on a base 17, and an H-shaped steel web WB, for example, a workpiece W, is cut into the portal frame 14 while rotating by a motor M 3. A machining head 15 provided with a drill 16 for performing dawn machining is provided.
[0057]
The machining head 15 provided with the drill 16 can be moved and positioned in the Y-axis direction and the Z-axis direction by, for example, a motor / ball screw mechanism (not shown).
[0058]
On the base 17, on the left side is a machining head 2 equipped with a drill 1 for drilling the left flange LF of H-section steel while rotating by a motor M2, and on the right side is similarly rotated by a motor M2. On the other hand, machining heads 2 each having a drill 1 for drilling a right flange RF of H-shaped steel are provided.
[0059]
A moving plate 18 is provided on the left side of the base 17. The moving plate 18 is slidably coupled to a Y-axis guide 20 and is movable in the left-right direction (Y-axis direction) by a hydraulic cylinder 19.
[0060]
On the moving plate 18, the processing head 2 is slidably coupled via a Y-axis guide 21, and the processing head 2 is movable in the left-right direction by the hydraulic cylinder 4 described above.
[0061]
A drill 1 that is rotationally driven by the motor M2 is attached to the machining head 2. The drill 1 can be moved and positioned in the vertical direction (Z-axis direction) by, for example, a motor / ball screw mechanism (not shown). Yes.
[0062]
One end of the elastic member 3 such as the coil spring described above is attached to the opposite side of the drill 1 on the processing head 2 as shown in the figure, and the other end of the elastic member 3 is connected to the hydraulic cylinder 4. The piston rod 5 is attached.
[0063]
In this case, the other processing head 2 provided on the right side of the base 17 has the same structure as the processing head 2 on the moving plate 18 described above, and therefore description thereof is omitted.
[0064]
Furthermore, fixed vices 22 and 23 are provided on the front side (Y-axis direction) and the rear side of the base 17 (FIG. 9) on the right side (Y-axis direction). Vise 24 and 25 are provided.
[0065]
Further, below the fixed vices 22 and 23 and the movable vices 24 and 25 (in the Z-axis direction) (FIG. 8), support rollers 28 and 29 that support the flanges RF and LF of the H-shaped steel are rotatably supported. ing.
[0066]
With this configuration, after the work W is loaded through the conveyor roller 26 (FIG. 9), the hydraulic cylinder 19 is operated to move the moving plate 18 forward (in the Y-axis direction). The workpiece W is clamped and positioned by the fixed vices 22 and 23 (step 101 in FIG. 10).
[0067]
In this state, the drill 1 (FIG. 8) is positioned in the vertical direction (Z-axis direction), the motor M2 is driven to rotate the drill 1 (step 102 in FIG. 10), and then the hydraulic cylinder 4 ( By actuating FIG. 8), the machining head 2 is brought close to the workpiece W and a predetermined operation is performed (step 103 and subsequent steps in FIG. 10).
[0068]
The operation of the present invention having the above configuration will be described below with reference to FIG.
[0069]
(1) Operation before starting cutting.
In step 101 of FIG. 10, the workpiece W is carried in and positioned, in step 102, the drill 1 is positioned in the vertical direction and rotated, and in step 103, the hydraulic cylinder 4 is advanced at a rapid feed rate and a cutting feed rate, and the machining head 2 is contacted.
[0070]
That is, the NC device 10 (FIG. 1) rotates the conveyor roller 26 of the drilling device (FIG. 9) and loads, for example, H-shaped steel as the workpiece W, and controls the hydraulic cylinder 19 to move the moving plate 18. Is moved forward (in the Y-axis direction), and the workpieces W are fixed by the movable vices 24 and 25 and the fixed vices 22 and 23 and positioned.
[0071]
In this state, the NC device 10 positions the drill 1 (FIG. 8) in the vertical direction (Z-axis direction), and drives the motor M2 to rotate the drill 1.
[0072]
At this stage (t0 in FIG. 2), the hydraulic cylinder 4 is stopped, and the rotating drill 1 is separated from the workpiece W.
[0073]
However, the NC apparatus 10 (FIG. 1) turns on the solenoid SOL (1) of the electromagnetic valve 7A constituting the direction switching circuit 7, turns off SOL (2), and solenoid SOL (9) of the electromagnetic valve 9A constituting the feed switching circuit 9. When 3 ▼ is turned on, the hydraulic cylinder 4 moves forward at a rapid feed speed (FIG. 4).
[0074]
As a result, the machining head 2 and the drill 1 also move forward at a fast feed speed and approach the workpiece W (t0 to t1 in FIG. 2), and the drill 1 has hit the workpiece W (t1 in FIG. 2). The NC device 10 detected by the change in the current of the motor M2 that rotationally drives 1 turns off the hydraulic cylinder 4 by turning off the electromagnetic valve 9A of the feed switching circuit 9 after a predetermined time has elapsed (t2 in FIG. 2). When switched to the cutting feed speed, the piston rod 5 of the hydraulic cylinder 4 moves forward against the restoring force of the elastic member 3 and comes into contact with the machining head 2 (t3 in FIG. 2).
[0075]
In this case, the machining head 2 remains stopped until the piston rod 5 of the hydraulic cylinder 4 comes into contact (t3 in FIG. 2) after the drill 1 hits the workpiece W (t1 in FIG. 2). Is not done.
[0076]
(2) Operation after the start of cutting.
[0077]
(2) -A First cutting (t3 to t4 in FIG. 2).
[0078]
In step 104 of FIG. 10, the hydraulic cylinder 4 is moved forward at the cutting feed speed while being in contact with the machining head 2 to perform cutting, and in step 105, it is determined whether or not the drill 1 has penetrated the workpiece W. If it does not penetrate (NO), it is determined in step 106 whether or not a predetermined time T has elapsed. If not (NO), the process returns to step 104 and the same operation is repeated.
[0079]
That is, as described above, when the piston rod 5 of the hydraulic cylinder 4 comes into contact with the machining head 2 at the cutting feed rate (t3 in FIG. 2), the machining head 2 moves forward at the cutting feed rate and the rotating drill 1 is moved. The workpiece W is cut and the hole Q machining is started.
[0080]
When the hole Q machining is started (see FIG. 1), the NC device 10 determines whether or not the drill 1 has penetrated the workpiece W. If the drill 1 does not penetrate, machining is started for a certain period of time (t3 in FIG. 2). It is determined whether T has elapsed.
[0081]
For example, the NC device 10 (FIG. 1) indicates that the drill 1 has penetrated the workpiece W, that a certain period of time has elapsed since the torque of the drive motor M2 and, therefore, the current has changed. Each determination is made when a predetermined time T stored in a memory (not shown) in 2) has passed.
[0082]
If the predetermined time T has not elapsed since the machining start (t3 in FIG. 2) (for example, the current time t ′), the machining head 2 is connected to the piston rod of the hydraulic cylinder 4 as before, as shown in the figure. 5 is pushed forward by the cutting feed speed, the rotating drill 1 cuts the workpiece W, and the hole Q processing is continued until t4.
[0083]
(2) -B Cutting of the chips K by the first stopped drill 1 (t4 to t5 to t6 in FIG. 2).
[0084]
However, if it is determined in step 106 in FIG. 10 that the predetermined time T has elapsed (YES), the hydraulic cylinder 4 is retracted by the restoring force of the elastic member 3 in step 107, and in step 108, the hydraulic cylinder 4 Is moved forward and brought into contact with the machining head 2.
[0085]
That is, the NC device 10 (FIG. 1) configures the feed switching circuit 9 (FIG. 1) when it is determined that a fixed time T has elapsed from the start of machining (t3 in FIG. 2) (t4 in FIG. 2). The hydraulic cylinder 4 is temporarily stopped by turning off the solenoid SOL (1) constituting the direction switching circuit 7 and turning on the solenoid SOL (2) while the solenoid SOL (3) of the solenoid valve 9A is kept off. After that, the piston rod 5 of the hydraulic cylinder 4 is retracted by the restoring force of the elastic member 3, and thereafter (t5 in FIG. 2), the solenoid SOL (3) of the electromagnetic valve 9A of the feed switching circuit 9 remains in the direction. When the solenoid SOL (1) of the solenoid valve 7A of the switching circuit 7 is turned on and the solenoid SOL (2) is turned off, the piston rod 5 of the hydraulic cylinder 4 moves forward at the cutting feed speed, and the machining head 2 Contact (t6 in FIG. 2).
[0086]
In this case, as shown in FIG. 2, the rotating drill 1 hits the workpiece W from the time when the piston rod 5 of the hydraulic cylinder 4 starts to retract until it comes into contact with the machining head 2 (t4 to t5 to t6). Then, the chips K are divided while stopped.
[0087]
(2) -C Second cutting (t6 to t7 in FIG. 2).
[0088]
In step 108 of FIG. 10, after the hydraulic cylinder 4 is moved forward and brought into contact with the machining head 2, the process returns to step 104 and the same operation is repeated, and cutting is performed with the hydraulic cylinder 4 in contact with the machining head 2. Move forward at feed rate to perform cutting.
[0089]
That is, at t6 in FIG. 2, the piston rod 5 of the hydraulic cylinder 4 is in contact with the machining head 2 and moves forward at the cutting feed speed. Therefore, the machining head 2 is also moved forward at the same speed, and the rotating drill 1 is rotated. The workpiece W is cut again and the hole Q machining is continued.
[0090]
In this way, the second cutting is performed, and the same operation as the operation during the first cutting (t3 to t4 in FIG. 2) is performed.
[0091]
That is, if the drill 1 does not penetrate the workpiece W in step 105 in FIG. 10 (NO), it is determined in step 106 whether or not a predetermined time T has elapsed, and if not (NO). Returning to step 104, the cutting process is continued.
[0092]
For example, at the current time t ″ in FIG. 2, since a certain time T has not elapsed since the start of reworking (t6 in FIG. 2), as shown in the figure, the machining head 2 is connected to the hydraulic cylinder 4 as before. The piston 1 is pushed by the piston rod 5 to advance at the cutting feed speed, and the rotating drill 1 cuts the workpiece W to continue the hole Q machining, and this state continues until t7.
[0093]
In this way, the second cutting is performed.
[0094]
(2) -D Cutting of the chips K by the second stopped drill 1 (t7 to t8 to t9 in FIG. 2).
[0095]
If it is determined in step 106 that the predetermined time T has elapsed (t7 in FIG. 2), the hydraulic cylinder 4 is retracted by the restoring force of the elastic member 3 in step 107, and in step 108, the hydraulic cylinder 4 Is moved forward and brought into contact with the machining head 2, during this time (t7 to t8 to t9 in FIG. 2), the rotating drill 1 hits the workpiece W and stops in the same manner as before (t4 to t5 to t6 in FIG. 2). The swarf K is cut off as is.
[0096]
As described above, according to the present invention, the first cutting (t3 to t4 in FIG. 2), the cutting of the chips K by the first stopped drill 1 (t4 to t5 to t6 in FIG. 2), the second time Step feed operation from step 104 to step 108 in FIG. 10 such as cutting (t6 to t7 in FIG. 2), cutting of chips K by the second stopped drill 1 (t7 to t8 to t9 in FIG. 2). In the drilling apparatus, the drill life can be extended, the processing time can be shortened, and chips can be divided quickly and easily.
[0097]
(3) Operation after completion of cutting (t10 to t11 in FIG. 2).
[0098]
When performing the step feed operation as described above, if it is determined in step 105 of FIG. 10 that the drill 1 has penetrated the workpiece W (YES), in step 109, the hydraulic cylinder 4 is returned to the rapid return speed. To move the machining head 2 away from the workpiece W.
[0099]
That is, when the NC device 10 (FIG. 1) detects that the drill 1 has penetrated the workpiece W by detecting a change in the current of the motor M2 (t10 in FIG. 2), the direction switching circuit 7 ( 1) Solenoid SOL (1) of solenoid valve 7A is turned off and SOL (2) is turned on, and solenoid SOL (3) of solenoid valve 9A of feed switching circuit 9 is turned on (FIG. 7).
[0100]
As a result, the piston rod 5 of the hydraulic cylinder 4 retreats at a fast return speed, and accordingly the machining head 2 is released from the cutting resistance of the workpiece W and separated from the piston rod 5 by the restoring force of the elastic member 3. Then, the workpiece is separated from the workpiece W and returned to the original position (t11 in FIG. 2).
[0101]
In the above embodiment, the drill 1 for cutting the left and right flanges LF and RF of the H-section steel (FIG. 8) has been described in detail. However, the present invention is not limited to this, and the web WB of the H-section steel is used. Needless to say, the present invention is also applicable to the drill 16 for cutting and has the same effect.
[0102]
【The invention's effect】
As described above, according to the present invention, the chips can be divided without separating the drill from the workpiece, so that the chips are not caught between the drill and the workpiece, or the drill does not strike the workpiece again. The service life of the drill is increased, the machining time is shortened, and the elastic member absorbs the bending of the machining head and workpiece due to the machining load. The effect was achieved that the division can be performed quickly and easily.
[0103]
[Brief description of the drawings]
FIG. 1 is an overall view showing an embodiment of the present invention.
FIG. 2 is an operation explanatory diagram of the present invention.
FIG. 3 is a diagram showing the relationship between the piston rod 5 and the machining head 2 when the hydraulic cylinder 4 according to the present invention is cutting fed and retracted.
FIG. 4 is a diagram showing a fast-forward mode according to the present invention.
FIG. 5 is a diagram showing a cutting feed mode according to the present invention.
FIG. 6 shows a reverse mode according to the present invention.
FIG. 7 is a diagram showing a fast return mode according to the present invention.
FIG. 8 is a front view of a drilling device to which the present invention is applied.
FIG. 9 is a plan view of a drilling apparatus to which the present invention is applied.
FIG. 10 is a flowchart for explaining an operation according to the present invention.
FIG. 11 is an explanatory diagram of the first prior art.
FIG. 12 is an explanatory diagram of the second prior art.
[Explanation of symbols]
1 Drill
2 Processing head
3 Elastic members
4 Hydraulic cylinder
5 Piston rod
7 Direction switching circuit
7A 4 port 3 position solenoid valve
8 Flow control circuit
8A Flow adjustment valve
8B Check valve
9 Feed switching circuit
9A 2-port 2-position solenoid valve
10 NC unit
11 Hydraulic pump
12 Hydraulic filter
13 Oil tank
W Work

Claims (5)

A hydraulic circuit that includes a machining head having a rotatable drill, a hydraulic cylinder that moves the machining head, and an elastic member that is fitted between the hydraulic cylinder and the machining head, and that drives the hydraulic cylinder includes: Including a direction switching circuit for switching to move the hydraulic cylinder forward or backward,
The restoring force of the elastic member is smaller than the thrust of the hydraulic cylinder, and the hydraulic cylinder is stopped by switching the direction switching circuit to the reverse mode while the elastic member is contracted during drilling. In addition, the drilling apparatus is characterized in that the piston rod of the hydraulic cylinder moves backward with respect to the machining head by the restoring force of the elastic member in a state where the rotating drill is brought into contact with the workpiece and stopped.  The drilling device according to claim 1, wherein the elastic member is constituted by a coil spring, an air cushion, or rubber. A drilling method using the drilling device according to claim 1,
(1)
The hydraulic cylinder is advanced cutting feed rate being in contact with the machining head performs drilling work by the drill to rotate,
(2)
In a state in which a said drilling during machining elastic member is contracted, the direction switching circuit at the time of stopping the hydraulic cylinder is switched to the reverse mode, in a state of stopping abutted against the drill which rotates the workpiece The piston rod of the hydraulic cylinder retreats with respect to the machining head by the restoring force of the elastic member and divides the chips in a state where the rotating drill hits the work and stops, and the above (1) and (2) A drilling method characterized by repeating the operation. In the above operation (2), when the hydraulic cylinder is moved backward with respect to the machining head and then advanced again by the direction switching circuit, the hydraulic cylinder is advanced at the cutting feed speed to resist the restoring force of the elastic member. The drilling method according to claim 3, wherein the operation moves to the operation of (1). The drilling method according to claim 4, wherein the rotating drill hits the workpiece and stops to divide chips after the hydraulic cylinder starts retreating, reversely moves forward and comes into contact with the machining head.

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