JPH0733753B2 - Grooving method and device using liquid jet - Google Patents

Description

TECHNICAL FIELD The present invention relates to a groove excavating method and apparatus using a liquid jet. In the present specification, the liquid jet also includes a so-called abrasive water jet in which the abrasive is turbid in the liquid.

(B) Conventional Technology FIG. 6 shows a conventional groove excavator using a liquid jet. A liquid jet nozzle (hereinafter, simply referred to as a nozzle in the present specification) 100 is attached to a tip end portion of a rotating tool 102 at a predetermined angle θ with respect to an axis, and the liquid jet nozzle is rotated while rotating the tool 102. To excavate a hole having a diameter larger than that of the tool 102 in the object 104 to be excavated, and the tool 102 is moved along the excavation surface (in the left-right direction in the drawing) to form a groove 106.
Can be formed. The groove 106 can be made to have a predetermined depth by repeating the above operation.

(C) Problems to be Solved by the Invention However, according to the conventional groove excavating method and apparatus using the liquid jet as described above, as shown in FIG. If there is a material having high hardness such as, the uncut portion 206 is not completely excavated, and the unexcavated portion 206 is generated. When the abrasive in the liquid jet is clogged and the excavation is performed with insufficient supply of the abrasive, even if there is no foreign matter having a high hardness in the excavation portion, the excavation having the shape indicated by the symbol A is used. The remaining portion 206 occurs. When the excavation equipment collides with the unexcavated portion 206, the equipment is damaged or the excavation becomes impossible. Therefore, conventionally, changes such as sound and vibration during excavation are detected, or changes in excavation resistance are detected using a load cell, etc., and an abnormality is judged when there is a change over a predetermined level. Then, after stopping the excavation equipment once, the excavation residue 20
It took 6 hours to cut and remove it. Therefore, it is difficult to automate the excavator. The present invention aims to solve such problems.

(D) Means for Solving the Problems The present invention is designed to detect an abnormality in the operation of a nozzle (18) that ejects a liquid jet by detecting an abnormality in the speed of a nozzle driving device (10 and / or 12) or a driving current value. The above problem is solved by detecting and retracting the nozzle, returning the nozzle to the coordinates before the abnormality occurred, re-digging the abnormal portion, and then restarting the normal excavation work. That is, in the groove excavation method using the liquid jet according to the present invention, when the nozzle that injects the liquid jet is driven at a constant speed, the operating speed in the direction orthogonal to the axis of the excavation direction of the nozzle is decreased, or , Detecting that the operation has stopped, judging the excavation abnormality, retracting the nozzle, returning the nozzle to the coordinates before the abnormality occurred, re-digging the abnormal part,
The normal excavation operation is restarted. Further, in the case where the nozzle for injecting the liquid jet is variable-speed driven during one excavation stroke, the set moving speed for each coordinate in the direction orthogonal to the axis of the excavation direction during one excavation stroke of the nozzle is stored in advance. , The actual moving speed for each coordinate of the nozzle during excavation is compared with the above set moving speed, and if there is a speed difference between the two speeds that is greater than or equal to the preset value, it is judged that the excavation is abnormal and the nozzle is retracted. After returning the nozzle to the coordinates before the abnormality occurred and re-digging the abnormal point,
The normal excavation operation is restarted. The re-excavation of the abnormal portion may be performed at a speed lower than the preset speed for the corresponding coordinates and over the area range preset for the re-excavation. Further, the groove excavating device using the liquid jet of the present invention is a frame (2) that can be moved and fixed at a predetermined position, and a movement that can be moved on the frame (2) by a forward-backward movement device (6). A table (4), a rocking device (10) mounted on the moving table (4) and capable of rocking a lever (20) at the tip within a plane, and a tip mounted on the moving table (4) Reciprocating motion device (12) capable of repetitively moving the nozzle mounting member (16) of the above-mentioned part and including a motion component orthogonal to the one plane, and capable of ejecting a liquid jet attached to the nozzle mounting member (16) Nozzle (18) and swing device (1
0) and / or the repetitive exercise device (12), or the abnormality detection sensor (78 or 79) attached to the prime mover (46 and / or 66) of either one, and the abnormality detection sensor (78 or 7).
9) A signal from the controller is used as an input to judge an abnormal operation, and command the nozzle (18) to move to the coordinates before the abnormality occurred, re-excavate, return to the coordinates of the abnormality occurrence point, and resume normal excavation. (73) and having a nozzle mounting member (1
The lever (20) is repeatedly movably supported by the lever (20). The reference numerals in parentheses indicate the corresponding members in the embodiments described later.

(E) Operation (Operation of claim 1) For example, a rotational position sensor (abnormality detection sensor) is attached to the drive shaft of the nozzle drive device, and when there is no abnormality, the nozzle drive device that rotates at a constant speed is driven. The axis causes the rotary position sensor to generate a signal at regular time intervals, which detection signal is input to the control device and compared with a preset tolerance time interval. When this detection signal deviates from the permissible value, the control device judges that the rotation speed is abnormal, and first sends a signal for retracting the nozzle from the spot to the forward / backward movement device. Next, the control device moves the nozzle to the coordinates before the abnormality occurred, and re-excavates the abnormal portion.
This abnormal area is generally caused by foreign matter having higher hardness than other areas, and has a certain size.
It is advisable to excavate the area range set in advance assuming the size of the abnormal portion at a speed lower than the normal excavation speed. When the excavation of the abnormal part is completed, the normal excavation is restarted.

(Operation of Claim 2) The moving speed of the nozzle during one excavation stroke is made to differ depending on the coordinate position, and the speed for each position is stored in the storage device provided in the control device. For example, a rotary encoder (abnormality detection sensor) attached to the drive shaft of the nozzle drive device detects the rotation angle of the drive shaft at each position during one excavation stroke, and this detection signal is sent to the control device. Then, the actual velocity is calculated and compared with the velocity of the corresponding stored position. The control device determines that an abnormality has occurred when the difference between the two values becomes larger than a preset value, and the control device first sends a signal for retracting the nozzle from the spot to the forward / backward movement device. .
Subsequent operations are performed by the same procedure as in the case of the above item 1, and the normal operation is restarted after the excavation of the abnormal portion is completed.

By doing this, even if an abnormality such as a remaining excavation occurs, it is possible to reliably detect the remaining excavation without manually removing the remaining excavation. The re-drilling is repeated, and when the re-drilling is completed, the normal excavation work can be resumed.

(F) Example FIGS. 2 and 3 show an example of a groove excavating device using a liquid jet to which the present invention is applied. Moving stand 4 on frame 2
Are provided so as to be movable in the left and right directions in FIGS. 2 and 3. The frame 2 itself is attached to the tip of a robot arm (not shown) and can be moved to a desired position and stopped. The moving table 4 is driven by a motor 6 (a forward / backward moving device) provided on the frame 2 via a pulley 7 and a belt 8 to control the position. A connection member 5 fixed to the belt 8 is attached to the bottom surface of the moving table 4. The moving table 4 is provided with a rocking device 10 and a repeating motion device 12. The rocking device 10 and the repetitive motion device 12 will be described below.

(Oscillating Device 10) The oscillating device 10 has a Y-shaped lever 20 having a bifurcated portion 20a and 20b, and a pin 22 with one end side 24a fitted to the slot of the tip of the bifurcated portion 20a. The link 24 is rotatably supported and has a connecting hole on the other end side 24b, and the one end side 28a rotatably supports the forked portion 20b with the pin 26, and the other end side projecting portion 28b. Arm 28 provided with, one end side 24a of link 24 and one end side 28a of arm 28
A link 34 supported by pins 30 and 32 respectively
And a drive device 36 for swinging the link 24 in the left-right direction in FIG. 2 about the pin 32 as a fulcrum.
Pivot lever 20 by swinging 24 to the left and right.
It is possible to swing up and down in a plane parallel to the paper surface in FIG. The lever 20 is provided with a hole 20c for mounting a fork 56 of the repetitive motion device 12 which will be described later and a bearing portion 20d which also rotatably supports a shaft portion of an eccentric cam 60 which will be described later. The drive device 36 includes a cylindrical case 3 having a swing bearing portion 37a at its end.
7, a screw shaft 38, one end of which is connected to the swing bearing portion 37a and the other end of which is connected to the link 24 and the arm 28 by the pin 30, a rod-shaped nut 40 which is screwed to the screw shaft 38, and the nut 40, which is integrated with the nut 40. Mounted on the case 37 and rotatably supported by a bearing 50 in the case 37, and a gear 44 that meshes with the gear 42.
And a motor mounted in the case 37 to drive the gear 44
46 and. A speed reducer 52 and a positioning encoder 54 are attached to the motor 46. The swing bearing portion 37a of the case 37 is swingably supported by a trunnion mechanism 48 fixed to the moving table 4. This links
24 moves to the left and right in the figure with pin 32 as a fulcrum, and arm 28
Even if the distance between the shaft and the
By swinging in the vertical direction in the figure using the 48 trunnion shaft as a fulcrum, it is possible to follow changes in the inter-axis distance. The drive device 36 is designed so that the rotation direction is reversed at a preset cycle, which causes + β in FIG.
It is possible to swing the lever 20 in a predetermined cycle within the angle range from -β.

(Repetitive exercising device 12) The repeating exercising device 12 includes the hole 20c of the lever 20 of the rocking device 10.
A fork 56 having a shaft portion 56a fitted therein and having a slit provided on one end side, and an intermediate portion fitted to the above-mentioned insertion slot and rotatably supported by a pin 58 having a nozzle mounting portion 16a at one end. On the other hand, the head 16 having the spherical surface receiving portion 16b at the other end and the spherical end portion 60 at the tip end are eccentric to each other.
an eccentric cam 60 having a formed therein and fitted to the spherical surface receiving portion 16b and a joint portion 60b formed at the other end, and a joint portion 62a combined with the joint portion 60b of the eccentric cam 60 at one end. It has a universal joint 62 having a joint portion 62b at the other end, a rotary joint 64 combined with the joint portion 62b, and a rotary drive device 66 for rotating the rotary joint 64. The shaft portion of the eccentric cam 60 is rotatably supported by the bearing portion 20d of the lever 20 of the rocking device 10. The universal joint 62 has a spline hole portion 68 in an intermediate portion and a spline shaft portion 70 that is fitted in the spline hole portion 68 so as to be movable in the axial direction, and can be expanded and contracted in the axial direction. A speed reducer 72 and a motor 76 are attached to the rotary drive device 66. By rotating the rotary joint 64 by the rotary drive device 66, the eccentric cam
It is possible to repeatedly move the spherical end portion 60a of 60 in a circular motion. That is, the head 16 is the shaft of the fork 56.
It is possible to perform repetitive motion including a motion component in a direction orthogonal to the paper surface of FIG. 2 with 56a and the pin 58 as a fulcrum.

On the other hand, a rotary encoder 78 is attached to the rear part of the motor 76, and the axis of the rotary encoder 78 is the motor.
It is connected to the rotating shaft of 76 to generate an angle signal for each predetermined angle during one rotation of the motor 76. This signal is input to the control device 73, converted into speed based on the measurement time of a timer incorporated therein, and treated as the actual speed. The control device 73 compares the execution speed and the set speed for each predetermined angle during one rotation to check whether the speed is within the allowable speed difference. The detection level of the speed fluctuation by the rotary encoder 78 does not need to be set to a very high level. For example, a speed of 50% or less of the set speed is 1
If it continues for more than a second, the controller 73 may determine that it is “abnormal”.

A nozzle 18 for ejecting a liquid jet is attached to the nozzle attachment portion 16a of the head 16. A high-pressure water hose 82 and an abrasive hose 84 are attached to the head 16, and the high-pressure water from the high-pressure water hose 82 and the abrasive from the abrasive hose 84 are mixed inside to the nozzle 18. A mixing chamber 80 for supplying is provided. The high pressure water hose 82 is supplied with high pressure water from a high pressure water pump (not shown), and the abrasive hose 84 is supplied with abrasive from a polishing material supply pump (not shown). The nozzle 18 can inject a grinding liquid, which is a mixture of high-pressure water and an abrasive in the mixing chamber 80, as a liquid jet onto the excavation surface 86.

A cover 88 is provided so as to separate the movable table 4 side and the jet injection unit 14 side. Cover 88 is link 24, arm 2
8, above two hoses 82, 84 and universal joint 6
2 is provided so as to penetrate therethrough, so that it is possible to prevent the equipment provided on the movable table 4 side from being contaminated due to the scattering of the liquid jet.

Next, the operation of this device will be described. First, the frame 2 is positioned and fixed by a robot arm (not shown). The movable table 4 is retracted to the left of the position shown in FIGS. 2 and 3 so that the nozzle 18 faces the excavation surface 86.
In this state, jet ejection is started. That is, the head 16 is passed through the high-pressure water hose 82 and the abrasive hose 84.
High-pressure water and an abrasive are respectively supplied to the above, and both are mixed in a mixing chamber 80, and a jet containing the abrasive is ejected from a nozzle 18. The jet ejected from the nozzle 18 cuts concrete, rock, etc. by high-pressure water and the kinetic energy of the abrasive. At the same time, the rotary drive device 66 is driven to rotate the rotary joint 64. This makes the universal joint
62 rotates to rotate eccentric cam 60. As a result, the head 16 is repeatedly moved in a circular motion in the angular range shown by + α to −α in FIG. 3 with the shaft center of the shaft portion 56a of the fork 56 and the shaft center of the pin 58 as a fulcrum, and the depth H is reached. A circular hole-shaped excavation is performed. On the other hand, the motor 46 of the drive device 36 is driven to rotate the gear 44 via the speed reducer 52. As a result, the gear 42 and the nut 40 are rotated, and the screw shaft 38 moves in the axial direction. The link 24 swings in the left-right direction in FIG. 2 around the pin 32 as a fulcrum, and accordingly, the lever 20 swings around the pin 26 in a plane parallel to the paper in the range shown from + β to −β. become. That is, the nozzle 18
As shown in FIG. 5, excavation is performed by swinging in the lateral direction while repeatedly performing circular motion.

Next, the method of the present invention using this apparatus will be described. The drive shaft of the repetitive motion device 12 rotating at a constant speed causes the encoder 78 to generate a signal at regular time intervals, which detection signal is input to the control device and compared with a preset permissible time interval. When this detection signal deviates from the permissible value, the control device judges that the rotation speed is abnormal, and first sends a signal for retracting the nozzle 18 from the spot to the motor 6. Next, the control device moves the nozzle 18 to the coordinates before the abnormality occurs, and re-excavates the abnormal portion. This abnormal part is generally caused by foreign matter such as reinforcing bars and stones that are harder than other parts, and has a certain size. Excavate within the area range set assuming the size of the section. The re-drilling is repeated until the excavation of the abnormal portion is completed, and when the re-drilling is completed, the normal excavation is restarted.

The above operation will be described with reference to FIG. Now the nozzle
The tip of 18 is at N1, and the center of rotation of pin 26 is
It is assumed that an abnormality of excavation is detected at N1 during excavation of the groove of depth H, which is in the middle of rocking from -β to + β in P1. The motor 6 is rotated by a command from the control device 73, and the tip of the nozzle 18 retracts from the point N1 to the point N2. The retreat distance L is preferably 1.5 to 2.0 times the excavation depth H. The control device 73 drives the motor 45 of the rocking device 10 to return the nozzle 18 to the point N3 at the coordinates before the abnormality occurred and the tip of the nozzle 18 faces the point N1. Re-excavation is performed by repeatedly moving around the point N3 between the angles + α and −α. That is, re-excavation is performed by causing the tip of the nozzle 18 to make a circular motion across the paper surface in the angle range from the point N4 to the point N5. When the re-drilling is completed, the tip of the nozzle 18 passes from the point N3 to the point N2 and returns to the point N1 by the operation reverse to the above, and the normal excavation work is restarted.

FIG. 4 shows a second embodiment of the present invention. The drive device 66 includes a motor 66, a speed reducer 72, and a torque limiter 74 provided between both members. Two sensor cams 77 are attached to the output shaft of the speed reducer 72 at rotational angle positions offset by 180 degrees.
Two proximity sensors 79 are attached to detect the passage of the. That is, in this second embodiment, a sensor cam is used instead of the rotary encoder 78 of the first embodiment shown in FIG.
77 and a proximity sensor 79 is used as an abnormality detection sensor.

Next, the operation of the second embodiment will be described. When the operation of the repetitive motion device 12 is interrupted by a foreign material having high hardness during excavation, the torque limiter 74 limits the drive torque of the motor 76 transmitted to the speed reducer 72, and damages the repetitive motion device 12 and the nozzle 18. Protect from. The proximity sensor 79 is a speed reducer 72.
The required time for each half rotation is measured and output to the control device 73. The control device 73 checks by comparing the preset second and the measured second, and when it detects a time longer than the preset second, it commands the re-digging operation.

It should be noted that an ammeter for detecting the current of the motor 76 may be provided to detect the abnormal rotation of the motor 78 due to the abnormal current value. Further, the motor 54 of the rocking device 10 may be provided with an abnormality detection sensor for detecting such an abnormality in excavation.

(G) Effect of the Invention As described above, according to the present invention, even if an abnormality such as an excavation residual portion occurs, the excavation residual portion is reliably detected without manually removing the excavation residual portion. Then, re-drilling is automatically repeated until it is removed,
When the re-drilling is completed, the normal excavation work can be resumed.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the operation of the nozzle when an excavation abnormality occurs according to the method of the present invention, and FIG. 2 is a front view of a groove excavating device using the liquid jet of the first embodiment to which the present invention is applied.
FIG. 4 is a sectional view taken along the line III-III in FIG. 2, FIG. 4 is a front view of a groove excavating device using the liquid jet of the second embodiment, and FIG. FIG. 6 is a diagram for explaining the excavation condition by a conventional groove excavation device using a liquid jet, and FIG. 7 is a diagram having an excavation residual portion generated during the trench excavation. 6 ... Motor (forward / backward movement device), 10 ... Oscillation device (nozzle drive device), 12 ... Repetitive movement device (nozzle drive device), 18 ... Nozzle, 73 ... Control device, 78 ... Rotary encoder (Abnormality detection sensor), 79 ... Proximity sensor (Abnormality detection sensor).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koji Oshinoya, 1-6-1, Funakoshi Minami, Aki-ku, Hiroshima-shi, Hiroshima Prefecture Japan Steel Works, Ltd. (72) Hiroshi Miyahara 1 Funakoshi-minami, Aki-ku, Hiroshima-shi, Hiroshima Chome 6-1 Japan Steel Works, Ltd. (72) Inventor Yoshiharu Miyanaga 6-15-1 Ginza, Chuo-ku, Tokyo Power source development Co., Ltd.

Claims (4)

[Claims] 1. A method of excavating a groove using a liquid jet for forming a deep groove in an excavation part, wherein the operation speed of a nozzle for injecting the liquid jet in a direction orthogonal to the axis of the excavation direction is lowered or the operation is After detecting the stop, judge the excavation abnormality, retract the nozzle, return the nozzle to the coordinates before the abnormality occurred, re-excavate the abnormal part, and restart the normal excavation operation. A trench excavation method using a characteristic liquid jet. 2. A groove excavation method using a liquid jet for forming a deep groove in an excavation portion, wherein setting is made for each coordinate in a direction orthogonal to an axis line of the excavation direction in one excavation stroke of a nozzle for jetting the liquid jet in advance. The moving speed is stored in memory, the actual moving speed for each coordinate of the nozzle during excavation is compared with the set moving speed above, and if there is a speed difference between the two speeds that is greater than or equal to the preset value, the excavation error is detected. Judging, retracting the nozzle, returning the nozzle to the coordinates before the abnormality occurred, re-digging the abnormal point, and then restarting the normal drilling operation. . 3. Re-excavation of an abnormal portion is performed at a speed lower than a speed preset for corresponding coordinates and over an area range preset for re-excavation. A groove excavation method using the liquid jet according to 2. 4. A frame (2) which can be moved and fixed to a predetermined position, a movable table (4) movable on the frame (2) by a forward and backward movement device (6), and a movable table (4). ), A swinging device (10) capable of swinging the lever (20) at the tip end in one plane, and a moving table (4).
And a liquid jet mounted on the nozzle mounting member (16) and a repetitive motion device (12) mounted on the nozzle and capable of repetitively moving the nozzle mounting member (16) at the tip end including a motion component orthogonal to the one plane. A nozzle (18) capable of injecting air, and a prime mover (46 and / or) of the rocking device (10) and / or the repetitive motion device (12).
Anomaly detection sensor (78 or 79) attached to section 66)
And the signal from the abnormality detection sensor (78 or 79) as input to judge the abnormality of the operation and move the nozzle (18) to the coordinates before the abnormality occurred, re-excavate, return to the coordinates of the abnormality occurrence point, normal And a control device (73) for instructing resumption of excavation, and a nozzle mounting member (16) is a groove excavation device using a liquid jet supported by a lever (20) so as to be repeatedly movable.