JP5155416B2 - Dry ice powder blasting apparatus and method - Google Patents

Description

  The present invention relates to a blasting apparatus and a method for injecting dry ice powder onto an object together with compressed air.

  Patent Document 1 discloses a technique for performing a predetermined process, for example, a process (cleaning) for removing dirt adhered to an object by spraying dry ice powder obtained by cutting a dry ice block onto the object together with compressed air. Yes.

Japanese Patent No. 3924573

  According to the dry ice blasting apparatus of Patent Document 1, the dry ice block is rotated and cut in the manner of making so-called shaved ice to produce dry ice powder, and the dry ice powder is supplied to the spray gun with a powder hose and a pressure source. Compressed air from each is supplied by an air hose, and dry ice powder is sprayed from the spray gun together with the compressed air onto the object to perform, for example, a cleaning operation.

  However, when the spray gun is turned on and off in the course of the cleaning operation to stop and restart, dry ice powder tends to remain in the powder hose and the like, and when the powder particles are combined and frozen in the hose ( In other words, there is a problem that the ice is clogged in the hose and it becomes impossible to inject, and even if it can be injected, the mass of the binding powder (ice block) becomes large, and when it collides with an object, damage such as a collision mark occurs. There is a fear.

  This invention makes it a subject to eliminate the trouble caused by the dry ice powder remaining in the inside of a hose etc. icing by the on-off of an injection part.

Means for Solving the Problems and Effects of the Invention

The present invention is a blasting apparatus for spraying dry ice powder together with compressed air onto an object,
A motor that rotates the dry ice block;
A cutting blade that cuts into a rotating dry ice block and cuts it,
A hopper for storing dry ice powder obtained by cutting a dry ice block;
An injection unit that is held by an operator and injects dry ice powder together with compressed air;
A powder hose that connects the jet part and the hopper to guide the dry ice powder of the hopper to the jet part,
An air hose that guides compressed air to the injection section;
An on / off operation unit that is provided in the injection unit and starts and stops the injection of compressed air and dry ice powder;
When the on / off operation unit of the injection unit is turned off, the driving of the motor is stopped and cutting of the dry ice block is stopped. After that, when the on / off operation unit of the injection unit is turned on, Until the time limit elapses, by supplying compressed air in a state where supply of dry ice powder is stopped, at least dry ice powder remaining in the powder hose is discharged from the injection unit, and after the time limit elapses A controller that controls to resume driving the motor and start cutting the dry ice block;
It is characterized by including.
This cleans the inside of the hose and the like when the injection unit is turned on.

Further, the present invention is a blasting apparatus for spraying dry ice powder onto a target object together with compressed air,
A motor that rotates the dry ice block;
A cutting blade that cuts into a rotating dry ice block and cuts it,
A hopper for storing dry ice powder obtained by cutting a dry ice block;
An injection unit that is held by an operator and injects dry ice powder together with compressed air;
A powder hose that connects the jet part and the hopper to guide the dry ice powder of the hopper to the jet part,
An air hose that guides compressed air to the injection section;
An on / off operation unit that is provided in the injection unit and starts and stops the injection of compressed air and dry ice powder;
When the on / off operation unit of the spray unit is turned off, the driving of the motor is stopped to stop the cutting of the dry ice block, and the supply of dry ice powder is continued until the time limit has elapsed since the off operation. By supplying compressed air in a stopped state, at least dry ice powder remaining in the powder hose is discharged from the injection unit, and then the motor is resumed when the on / off operation unit of the injection unit is turned on. And a controller that controls to start cutting the dry ice block;
It is characterized by including.
This cleans the inside of the hose and the like when the injection unit is off.

These make it difficult for dry ice powder to remain in the powder hose, so that the particles of the remaining dry ice powder combine and freeze to form a larger ice mass, and the combined ice mass does not form in the hose or the injection section. It is possible to prevent or reduce troubles such as clogging and a mass of ice with a large combined mass (powder mass) colliding with an object and damaging it .

  Therefore, the cutting blade cuts by cutting into the dry ice block by forward rotation of the motor, and does not cut without cutting into the dry ice block against reverse rotation of the motor. When the on / off operation unit of the injection unit is turned on, the motor is once reversely rotated and then turned to the normal rotation to start cutting.

  Cutting of the dry ice block is stopped by turning off the spray unit, but when the spray unit is turned on and spraying is resumed, the dry ice block is restarted by the motor to obtain dry ice powder. Will resume from the middle. When the dry ice block is stopped in the middle of cutting, it is normal that the cutting blade bites into the dry ice block and a step is generated there. If the motor is restarted in this state, a large torque is required to start cutting from that stage, and an excessive load is likely to be applied to the motor, but once the motor is reversed, the cutting edge of the cutting blade is moved away from the stage. Cutting can be resumed without applying an excessive load to the motor by causing the motor to rotate forward and applying momentum to the cutting blade to cause the stage to collide.

  The present invention further includes a powder particle size changing operation unit that changes the particle size of the dry ice powder by changing the number of rotations of the motor. For example, if the object is thin and weak, reducing the dry ice powder particle size and making the powder mass smaller by increasing the number of revolutions of the motor will reduce the impact energy at the time of injection and collision and damage it. Can be avoided. On the other hand, when cleaning dirt that is difficult to remove due to the strength of the object, lowering the motor speed and increasing the powder particle size to increase its mass will increase the energy at the time of collision and increase the cleaning power. be able to.

Further, the present invention is a blasting method for spraying dry ice powder together with compressed air onto an object,
Cutting the dry ice block by rotating it with a motor while biting the cutting blade into the dry ice block, storing the dry ice powder obtained by the cutting in the hopper,
The dry ice powder of the hopper is guided to the injection unit by the powder hose, and the compressed air from the pressure source is supplied to the injection unit by the air hose, and the dry ice powder is compressed air from the injection unit gripped by the operator. To be injected together with
When an on / off operation unit provided in the injection unit for starting and stopping injection of compressed air and dry ice powder is turned off, cutting of the dry ice block is stopped, and then the on / off operation unit of the injection unit is turned on. When operated, the dry ice powder at least remaining in the powder hose is discharged from the injection unit by supplying compressed air in a state where the supply of dry ice powder is stopped until the time limit has elapsed since the ON operation. In addition, the cutting of the dry ice block is started after the time limit has elapsed .

Further, the present invention is a blasting method for spraying dry ice powder together with compressed air onto an object,
Cutting the dry ice block by rotating it with a motor while biting the cutting blade into the dry ice block, storing the dry ice powder obtained by the cutting in the hopper,
The dry ice powder of the hopper is guided to the injection unit by the powder hose, and the compressed air from the pressure source is supplied to the injection unit by the air hose, and the dry ice powder is compressed air from the injection unit gripped by the operator. To be injected together with
When the on / off operation unit provided in the injection unit for starting and stopping the injection of compressed air and dry ice powder is turned off, the cutting of the dry ice block is stopped and the time limit has elapsed since the off operation. Until then, supplying dry air in a state where supply of dry ice powder is stopped causes at least dry ice powder remaining in the powder hose to be discharged from the spray unit, and then the on / off operation unit of the spray unit is turned on. In this case, the cutting of the dry ice block is started.

BRIEF DESCRIPTION OF THE DRAWINGS The whole schematic which shows simply the blasting apparatus which is one Example of this invention. FIG. 2 is a control system diagram of FIG. 1. The perspective view which shows the vicinity of the cutting blade and hopper of FIG. Schematic explaining the action of the injection gun. The flowchart which shows the control program of the blasting apparatus of FIG. Schematic which shows the process of the cleaning of the dry ice powder in a powder hose. Schematic following FIG. Schematic following FIG. 7 of supplying new dry ice powder after cleaning. Process drawing where the dry ice block is reversed once and then turned forward to resume cutting.

  A blasting apparatus 1 shown in FIG. 1 is configured to receive a frame 3 that can be moved by wheels 2, a motor 20 that rotates the dry ice block B through a holder 4, and dry ice powder P obtained by cutting the dry ice block B. A hopper 6 to be accommodated, an injection gun 7 as an injection unit which is held by an operator and injects dry ice powder P together with compressed air, and the injection gun 7 and the hopper 6 are connected to inject the dry ice powder P of the hopper 6. A powder hose 8 leading to the gun 7, an air hose 10 leading compressed air from the air compressor 9 as a pressurizing source to the spray gun 7, and start and stop of the spray of compressed air and dry ice powder P provided on the spray gun 7 An on / off lever 11 and a nozzle switch 12 are provided as an on / off operation unit.

  The frame 3 includes a placement portion 15 on which the dry ice block B is placed, and a cutting blade 17 is provided so as to slightly protrude upward from a slit 16 formed in the placement portion 15. The dry ice block B is placed so as to be pressed. The holder 4 includes a plurality of needles 4 a, and these needles 4 a bite into the upper surface of the dry ice block B and transmit rotational torque to the block B. The holder 4 is connected to a motor 20 via a drive shaft 18 and a speed reduction mechanism 19. The motor 20 is an electric motor or an air motor, and its output is distributed via a speed reduction mechanism 19 to a drive shaft 18 that rotates the holder 4 and a screw shaft 21 that lowers the holder 4 according to cutting. The screw shaft 21 is held by the speed reduction mechanism 19 and is screwed with a nut 22 provided on a part 3 a of the frame 3.

  For example, as shown in FIG. 3, the dry ice block B has a prismatic shape, the bottom surface of which is pressed against the cutting blade 17, and the drive shaft of the holder 4 moves on the rotary sliding surface 23 formed on the mounting portion 15. Rotate around 18. The hopper 6 only needs to have a shape in which the cross section gradually decreases from the upper opening 6a toward the lower part. In this example, the slit 16 formed in the mounting portion 15 is included in the center of the opening 6a. An inverted conical wax shape or a trumpet shape (a curved shape in which an inverted conical peripheral wall bulges toward the center line side) is provided, and a powder hose 8 is connected to the lower part thereof. In addition, the thin line drawn on the inner peripheral surface of the hopper 6 is for, for example, showing a trumpet-shaped curved surface in three dimensions, and the thin line itself does not indicate a special substance. In FIG. 1, the dry ice block B is placed on the placement unit 15 in a state where the holder 4 is at the rising end position, and then the holder 4, the speed reduction mechanism 19, and the motor 20 are pushed downward by the operator's force, for example. Then, the screw shaft 21 follows and rotates, and the needle 4a of the holder 4 pierces the upper surface of the dry ice block B and holds it.

  When the dry ice block B is rotated through the holder 4 by the rotation of the motor 20, the block B is cut by the cutting blade 17 to obtain the dry ice powder P, which is passed through the slit 16 of the mounting portion 15 to the hopper 6. Be contained. The screw shaft 21 is also rotated by the drive of the motor 20, and as the cutting progresses, the holder 4 is displaced downward by the action of the screw shaft 21, and the motor 20 stops at the lower limit position where the holder 4 approaches the cutting blade 17. The dry ice block B is placed on the placement unit 15. The motor 20 is connected to a controller 25, and an operation panel 26 is connected to the controller 25 as a powder particle size changing operation unit that changes the particle size of the dry ice powder P by changing the rotation speed of the motor 20. Are arranged at appropriate positions on the frame 3.

  The operation panel 26 is switched to, for example, a plurality of stages, thereby changing the rotation speed of the motor 20 and thus the particle size of the dry ice powder P obtained by cutting the dry ice block B. For example, when the dial is aligned with the scale 1 of the operation panel 26, the rotational speed of the motor 20 becomes the slowest, whereby the relative speed between the dry ice block B and the cutting blade 17 becomes small, so that the dry ice powder P with large particles can be obtained. In contrast, when the dial is adjusted to the scale 5 and the rotational speed of the motor 20 is increased, the relative speed between the cutting blade 17 and the dry ice block B is increased, and powder P having a small particle size is obtained.

  If the particle size of the powder P is small, its mass is small. Therefore, the collision energy when spraying the dry ice powder P together with the compressed air from the spray gun (nozzle) 7 to the predetermined object (for example, the object to be cleaned) 27 is small. If the particle size of the dry ice powder P is large, the mass of the dry ice powder P is large, and the energy of impact due to jetting is also large. Therefore, the particle size of the dry ice powder P is adjusted to a plurality of levels (5 levels in the illustrated example) or continuously and continuously according to the strength of the object to be blasted and the purpose of blasting.

  The compressor 9 as a pressurizing source is provided with wheels 29 and can move along with the blasting device 1, and compressed air generated by the compressor 9 is supplied to the air hose 10 through the compressor hose 30 and the electromagnetic valve 31. Then, it is guided to the spray gun 7 through the hose 10. The spray gun 7 is gripped by an operator. When the on / off lever 11 is gripped, the nozzle switch 12 built in the gun 7 is turned on, and when the lever 11 is released, the nozzle switch 12 is turned off.

  As shown in FIG. 2, the nozzle switch 12 is connected to the controller 25 together with the motor 20 and the electromagnetic valve 31, and supplies an on / off signal to the controller 25. The controller 25 includes a CPU 33, a timer 34, a sequence circuit 35, and a control program 36. For example, when receiving an ON signal from the nozzle switch 12, the controller 25 opens the electromagnetic valve 31 to guide compressed air from the compressor 9 to the nozzle gun 17. After the time limit is measured, the motor 20 is started via the sequence circuit 35. When receiving an off signal from the nozzle switch 12, the controller 25 outputs a command signal for stopping the motor 20 and closing the electromagnetic valve 31. The control program 36 is a program in which a program to be described later for controlling the entire blast apparatus 1 is written in a memory, and is executed by the CPU 33.

As shown in FIG. 4, a powder hose 8 and an air hose 10 are connected to the spray gun 7, and they merge to form one ejection hole. When compressed air flows from the air hose 10 at a high speed in the spray gun 7, the air in the powder hose 8 is sucked by the venturi effect, and the dry ice powder P present in the hopper 6 is sucked and supplied to the spray gun 7. The dry ice powder P is sprayed from the tip (nozzle) of the spray gun 7 in a state where the dry ice powder P is mixed in a mist state with compressed air. By making the hopper 6 into an inverted conical wax shape or a trumpet shape, the dry ice powder P is uniformly and smoothly guided to the spray gun 7 from the entire peripheral surface of the hopper 6 through the powder hose 8 in accordance with the venturi effect. . Note that the output of the air compressor 9, and the compressed air pressure, is about 0.1 MPa (megapascal) to 0.7 MPa (1 to 7 kgf / cm ² ), for example, and fine dry ice powder P having a small mass is used. Thus, powder injection for cleaning or the like is possible even at a low pressure of about 0.1 MPa (1 kgf / cm ² ). As a result, a so-called small-output baby compressor can be used as the air compressor 9, thereby moving a lightweight and small mobile air compressor that moves with the movement of the blasting device 1 (for example, moved by being pulled by the blasting device 1). Accordingly, the blasting device 1 can be moved to a necessary location together with the air compressor 9 and used for various purposes including cleaning.

  As shown in FIG. 9 (d), the cutting blade 17 bites into the bottom surface of the dry ice block B in the forward direction and performs cutting, but as shown in FIG. 9 (b), the cutting blade 17 rotates in the opposite direction. The direction or angle of the blade edge is set so that the cutting blade 17 does not bite into the dry ice block B during (reverse rotation).

  Next, the overall operation of the blasting apparatus 1 will be described based on the flowchart of the control program shown in FIG. In S1, when the power is turned on, the compressor 9 is started, and in S2, it is determined whether or not the dry ice block B has been placed at a predetermined position of the placement portion 15 (for example, a positioning switch is turned on). ). Then, in S3, the holder 4 descends and is pressed against the upper surface of the dry ice block B, and the needle portion 4a bites into the holder and holds the block B. In this step, for example, the screw shaft 21 in FIG. 1 can be rotated by a dedicated motor prepared separately from the motor 20 and the holder 4 can be lowered, or the holder 4 is lowered by an air cylinder or the like instead of the motor. You can also. In this example, the operator can manually push down the holder 4 via the speed reduction mechanism 19 and press it against the upper surface of the dry ice block B. In this state, when the operator grasps the lever 11 of the injection gun 7 and the nozzle switch 12 is turned on (S4), the solenoid valve (valve) 31 is opened in S5, and the compressed air generated in the compressor 9 is sent to the injection gun 7. Sent.

  Further, a predetermined time limit (for example, about 2 to 5 seconds) is set by the timer 34 of FIG. 2 in S6, and this state continues until the time is up in S7. In the order of explanation of the program in FIG. 5, it is a story at the time of the first start-up. For example, after S13, the nozzle switch 12 is turned on again by S4 (that is, the dry ice powder P is sprayed, which is once Assuming that the fuel is stopped and sprayed again), as shown in FIG. 6, the rotation of the dry ice block B is stopped and is not cut. However, since the solenoid valve 31 is in the open state, the compressed air is guided to the injection gun 7 through the air hose 10 and is ejected from the injection gun 7 at a high speed. Therefore, the dry ice powder remaining in the powder hose 8 due to the above-mentioned venturi effect. P is sucked toward the spray gun 7 and ejected together with the compressed air. As shown in FIG. 7, when the dry ice powder P remaining in the powder hose 8 is almost discharged out of the hose 8, a time limit elapses (time up in S7), and the motors 20 in S8 and S9 in FIG. This is the step of restarting cutting of the dry ice block B by the activation of.

  Here, as shown in FIG. 9A, in the state where the cutting of the dry ice block B is stopped halfway, the cutting blade 17 bites into the bottom surface of the block B and a step (step) is generated. If the motor 20 is driven as it is and cutting is started, a large load is applied to the motor 20. Therefore, as shown in FIGS. 9A and 9B, the motor 20 is reversely rotated by a predetermined angle (for example, within a range of 360 ° or less), and thereafter, as shown in FIGS. 9C and 9D, If the motor 20 is rotated forward and cutting is started from the position shown in (d), the relative speed is generated between the cutting blade 17 and the step of the dry ice block B at the start of cutting. The initial torque associated with can be reduced. This is steps S8 and S9 in FIG. By resuming the cutting, as shown in FIG. 8, the newly cut dry ice powder P is supplied to the spray gun 7 through the powder hose 8 after being cleaned. While the nozzle switch 12 remains on, the block B continues to be cut by the rotation (forward rotation) of the dry ice block B by the motor 20, and the dry ice powder P obtained thereby is sent to the spray gun 7, A cleaning operation or the like is performed by being injected onto the object 27 together with the compressed air.

  When the nozzle switch 12 is turned off in S10, the motor 20 is stopped in S11, the cutting of the dry ice block B is finished, the electromagnetic valve 31 is closed in S12, and the injection of the compressed air and the dry ice powder P from the injection gun 7 is performed. Stop. If the power switch is turned off in step S13, the process ends. If not, the process returns to step S4 to determine whether the nozzle switch 12 is turned on. Thereafter, the same process is repeated.

  As shown in FIGS. 6 to 8, when the injection from the injection gun 7 is resumed, after the dry ice powder P remaining in the powder hose 8 is discharged from the powder hose 8 and further from the injection gun 7, Since the dry ice powder P prepared in this step is supplied to the spray gun 7, the powders remaining in the powder hose 8 combine to form an ice lump, which causes clogging and damages the object. Inconvenience is eliminated.

  Note that the steps S6 and S7 (step A) in FIG. 5 may be inserted between S11 and S12. In this case, when the injection from the injection gun 7 is interrupted and the nozzle switch 12 is turned off, the motor 20 is stopped in S11, and the cutting of the dry ice block B is also stopped accordingly. Thereafter, the time limit is set by the timer 34, and the solenoid valve 31 of FIG. 1 is kept open until the time limit expires. Therefore, the compressed air from the compressor 9 continues to be supplied to the injection gun 7 through the air hose 10 within the time limit. Therefore, as shown in FIGS. 6 and 7, the dry ice powder P remaining in the powder hose 8 is discharged from the spray gun 7 to the outside within the time limit after the injection is stopped.

  In the above description, S5 to S7 in the controller 25 and the control program 36 shown in FIG. 5 function as cleaning means, and S5 to S7 in FIG. 5 serve as a powder supply control unit for the cleaning. Further, when the steps S6 and S7 are inserted between S11 and S12, the above-described controller 25 and these steps S11 and S12 serve as a powder supply control unit as a cleaning means. Similarly, the controller 25 and S10 and S11 in FIG. 5 are cutting stop control units, and S8 and S9 are cutting resumption control units. The description of the control program in FIG. 5 is also an embodiment of the blasting method of the present invention. In FIG. 5, S6 and S7 next to S5 and S6 and S7 next to S11 can be provided in an overlapping manner. In this case, the cleaning process is performed both when the spray gun 7 is turned on and off. Is done.

1 Blasting device 3 Frame 4 Holder 6 Hopper 7 Injection gun (injection part)
8 Powder hose 9 Air compressor (pressure source)
10 Air hose 11 ON / OFF lever 12 Nozzle switch (11 + 12 = ON / OFF control part)
DESCRIPTION OF SYMBOLS 15 Mounting part 17 Cutting blade 20 Motor 21 Screw shaft 25 Controller 26 Operation panel (powder particle size change operation part)
31 Solenoid valve 34 Timer 36 Control program

Claims (4)

A blasting apparatus for spraying dry ice powder together with compressed air onto an object,
A motor that rotates the dry ice block;
A cutting blade that cuts into a rotating dry ice block and cuts it,
A hopper for storing dry ice powder obtained by cutting a dry ice block;
An injection unit that is held by an operator and injects dry ice powder together with compressed air;
A powder hose that connects the jet part and the hopper to guide the dry ice powder of the hopper to the jet part,
An air hose that guides compressed air to the injection section;
An on / off operation unit that is provided in the injection unit and starts and stops the injection of compressed air and dry ice powder;
When the on / off operation unit of the injection unit is turned off, the driving of the motor is stopped and cutting of the dry ice block is stopped. After that, when the on / off operation unit of the injection unit is turned on, Until the time limit elapses, by supplying compressed air in a state where supply of dry ice powder is stopped, at least dry ice powder remaining in the powder hose is discharged from the injection unit, and after the time limit elapses A controller that controls to resume driving the motor and start cutting the dry ice block;
A dry ice powder blasting apparatus characterized by comprising: A blasting apparatus for spraying dry ice powder together with compressed air onto an object,
A motor that rotates the dry ice block;
A cutting blade that cuts into a rotating dry ice block and cuts it,
A hopper for storing dry ice powder obtained by cutting a dry ice block;
An injection unit that is held by an operator and injects dry ice powder together with compressed air;
A powder hose that connects the jet part and the hopper to guide the dry ice powder of the hopper to the jet part,
An air hose that guides compressed air to the injection section;
An on / off operation unit that is provided in the injection unit and starts and stops the injection of compressed air and dry ice powder;
When the on / off operation unit of the spray unit is turned off, the driving of the motor is stopped to stop the cutting of the dry ice block, and the supply of dry ice powder is continued until the time limit has elapsed since the off operation. By supplying compressed air in a stopped state, at least dry ice powder remaining in the powder hose is discharged from the injection unit, and then the motor is resumed when the on / off operation unit of the injection unit is turned on. And a controller that controls to start cutting the dry ice block;
A dry ice powder blasting apparatus characterized by comprising: A blasting method in which dry ice powder is sprayed onto an object together with compressed air,
Cutting the dry ice block by rotating it with a motor while biting the cutting blade into the dry ice block, storing the dry ice powder obtained by the cutting in the hopper,
The dry ice powder of the hopper is guided to the injection unit by the powder hose, and the compressed air from the pressure source is supplied to the injection unit by the air hose, and the dry ice powder is compressed air from the injection unit gripped by the operator. To be injected together with
When an on / off operation unit provided in the injection unit for starting and stopping injection of compressed air and dry ice powder is turned off, cutting of the dry ice block is stopped, and then the on / off operation unit of the injection unit is turned on. When operated, the dry ice powder at least remaining in the powder hose is discharged from the injection unit by supplying compressed air in a state where the supply of dry ice powder is stopped until the time limit has elapsed since the ON operation. And the dry ice powder blasting method starts cutting the dry ice block after elapse of the time limit . A blasting method in which dry ice powder is sprayed onto an object together with compressed air,
Cutting the dry ice block by rotating it with a motor while biting the cutting blade into the dry ice block, storing the dry ice powder obtained by the cutting in the hopper,
The dry ice powder of the hopper is guided to the injection unit by the powder hose, and the compressed air from the pressure source is supplied to the injection unit by the air hose, and the dry ice powder is compressed air from the injection unit gripped by the operator. To be injected together with
When the on / off operation unit provided in the injection unit for starting and stopping the injection of compressed air and dry ice powder is turned off, the cutting of the dry ice block is stopped and the time limit has elapsed since the off operation. Until then, supplying dry air in a state where supply of dry ice powder is stopped causes at least dry ice powder remaining in the powder hose to be discharged from the spray unit, and then the on / off operation unit of the spray unit is turned on. A dry ice powder blasting method characterized by starting cutting of a dry ice block .

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