54results about "Abrasive feeders" patented technology

This invention discloses a processing method for thermal spraying of flat workpieces. The processing method includes: taking a flat workpiece to be processed and constraining it using a processing fixture, the processing fixture including a support platform and a constraint component; placing the flat workpiece on the support platform and pressing the flat workpiece onto the support platform using the constraint component; operating a sandblasting device and a spraying device to sequentially perform sandblasting and spraying treatments on a first working surface of the flat workpiece; removing the flat workpiece, flipping it over, and pressing the flat workpiece onto the support platform again using the constraint component; operating the sandblasting device and the spraying device again to sequentially perform sandblasting and spraying treatments on a second working surface of the flat workpiece; removing the flat workpiece after sandblasting and spraying treatments and placing it in a heat treatment furnace for heat treatment to obtain the finished flat workpiece, maintaining the stability of the workpiece in the secondary processing, and improving the reliability and efficiency of the thermal spraying operation.

The utility model provides a kind of nozzle (10) for cavitation surface treatment, the nozzle (10) for cavitation surface treatment has nozzle head (13), the nozzle head (13) has: first plane (13a), it sprays liquid, and with jet axis (1) vertical;Second plane (13b), it is vertical with jet axis (1), is the opposite side of first plane (13a);Nozzle hole (21), the nozzle hole (21) has: semicylindrical discharge groove (23), it is configured in first plane (13a), extends in the first direction with jet axis (1) vertical;Ejection hole (25), it extends along jet axis (1), and is connected with discharge groove (23), and for the straight elliptical cylinder with long diameter in the first direction extending ellipse-shaped section;Import portion (27), it has straight conical surface (27a) with jet axis (1) as central axis, and is connected to ejection hole (25).

This invention provides a method for reducing undercut and overcutting in abrasive waterjet corner cutting. The method includes: spraying an abrasive waterjet onto a target material using a nozzle, maintaining the nozzle at a preset forward tilt angle, and feeding the nozzle along a first cutting direction relative to the target surface at a reference feed rate; adjusting the nozzle's orientation to be perpendicular to the target surface before it reaches the corner of the cutting trajectory, and pausing at the corner; after pausing, restoring the nozzle to its forward tilt angle, and feeding the nozzle along a second cutting direction relative to the target surface after the turn. By pausing the nozzle before the turn and employing a multi-stage, progressively increasing feed rate control strategy with a specific speed-length relationship after the turn, the method overcomes the problems of undercutting before the corner and overcutting after the corner, as well as poor cut geometry accuracy, caused by erosion energy attenuation and jet tailing effects.

This invention relates to the field of sandblasting technology for building exterior walls, and discloses a sandblasting decoration device for building exterior walls and its usage method. The device includes a mixing frame, with legs fixedly connected to its surface. A cylindrical frame is fixedly connected to the inner wall of the mixing frame, and a motor protective frame is fixedly connected to the bottom of the inner wall of the mixing frame. A sandblasting machine is installed at the bottom of the inner wall of the mixing frame, and a sandblasting component is installed at the top of the mixing frame. A mixing component is installed inside the cylindrical frame, and a cleaning component is installed on the inner wall of the cylindrical frame. In this invention, sand is placed into the mixing frame through a feed hole. The motor is started to drive the mixing component to mix the sand. The mixed sand enters the hollow frame through the connection between the sandblasting machine and the rotating ring. The sand inside the hollow frame enters the lifting frame through a discharge hole for storage. Finally, the sand enters the sandblasting head through the connection between the curved pipe and the central disc for sandblasting.

This utility model relates to the field of bridge expansion technology and is a wastewater collection trolley for water-jet cutting of bridge deck guardrail mounting platforms. It includes a water-jet cutting machine mounted on a support frame of a movable part located on the bridge deck. The water-jet cutting machine cuts the guardrail mounting platforms on the bridge deck. The movable part is connected to a wastewater collection unit, which includes a storage tank for collecting wastewater generated during the cutting process. The storage tank is mounted on the support frame. The guardrail mounting platforms on the bridge deck are cut using the water-jet cutting machine, which is moved by the movable part. Using the water-jet cutting machine reduces dust generation, and the wastewater generated is collected in the storage tank, minimizing the impact of wastewater on the bridge deck. The movable part includes a driving wheel and a driven wheel, both mounted on the support frame via mounting seats. The driving wheels and driven wheels are symmetrically arranged below the support frame.

The application relates to the technical field of scroll tube, in particular to a sand blasting device for scroll tube experiment, which comprises a base, a first motor is installed in the base, a rotating disc is rotatably arranged on the base, an output shaft of the first motor is connected to the rotating disc, a blanking groove is arranged on the rotating disc, at least two blanking grooves are arranged at intervals, a discharge pipe is fixedly connected to the base, an air inlet pipe is connected to the peripheral wall of the discharge pipe, a suction pipe is connected to one end of the discharge pipe, one end of the suction pipe is located above the rotating disc, a pressing plate is fixedly connected to one end of the suction pipe, one side plate surface of the pressing plate is attached to the rotating disc, a blanking hopper is fixedly connected to the base, the bottom of the blanking hopper is attached to the rotating disc, a blanking opening is arranged in the bottom of the blanking hopper, the sand blasting experiment of the scroll tube can be conveniently carried out, and the experimental efficiency is improved.

This utility model discloses an automated steel structure shot blasting machine, belonging to the field of steel structure shot blasting machines. A support frame is installed at the lower end of the material pipeline, and a vibrator is installed inside the support frame. A buffer base is installed at the lower end of the support frame. The vibrator drives the support frame and the material pipeline to vibrate, causing impurities in the shot blasting process to vibrate, and then dust is extracted through a dust extraction pipeline. A semi-circular plate is provided at the lower part of the opening of the material pipeline, and a connecting cylinder is connected to the semi-circular plate by a fixed rod. A limit rod is installed inside the connecting cylinder. The combination of the connecting cylinder and the guide roller ensures precise guidance and smooth passage of the material. The arc design of the guide roller reduces damage and improves polishing efficiency. The buffer sleeve and pulley provide cushioning and stability for the shot blasting machine. The "I"-shaped design of the sleeve is stable, and the through groove and annular buffer pulley reduce operating vibration and damage. The buffer pulley design improves durability, and the buffer rubber wheel reduces wear and extends the equipment life.

A method and apparatus keeps ice from interfering with the flow of cryogenic particles entrained in a flow exiting a blast nozzle during continuous operation of a particle blast system. A fluid stream having appropriate temperature, moisture content and flow rate flows through an annular passageway which surrounds the nozzle.

This utility model relates to the field of rack cleaning technology, specifically to a sandblasting machine for cleaning impurities on rack surfaces. The equipment includes an outer tank and a coaxially arranged inner tank. Three rack rings are evenly distributed on the outer wall of the inner tank and connected to a sandblasting pipe. A motor drives a transmission gear via a drive shaft to mesh with a gear on the side of the rack rings, enabling horizontal movement of the rack rings. Simultaneously, a belt drives a rotating platform that carries the rack to rotate synchronously. The lower gear of the rack ring meshes with a rotating gear of the sandblasting pipe, driving the sandblasting pipe to rotate 360° around the inner tank, forming a composite sandblasting trajectory. Infrared sensors at the ends of the nozzle branches detect the rack surface in real time, triggering valve opening and closing via infrared receivers. The outer tank cover prevents splashing, and the sand inlet supports dynamic sand replenishment. This equipment, through the synergy of mechanical motion and intelligent sensing, is suitable for the efficient cleaning needs of complex industrial rack surfaces, especially for precision cleaning of uneven, hollow, and interwoven structures, meeting industrial-grade continuous operation standards.

The application discloses a device for precisely controlling ice particle discharging amount and a use method thereof, and relates to the technical fields of abrasive gas jet and material conveying. The device comprises an ice particle storage bin and an ice particle discharging mechanism. The ice particle storage bin is provided with a bin body and a heat preservation cover from inside to outside. An ice storage chamber is formed in the bin body. A pre-cooling chamber is formed between the bin body and the heat preservation cover. An ice particle inlet is arranged on the bin body. An ice particle outlet is arranged at the bottom end of the bin body. A liquid nitrogen temperature control cavity is formed at the bottom of the heat preservation cover and is communicated with the pre-cooling chamber. The ice particle discharging mechanism is provided with a shell fixed in the liquid nitrogen temperature control cavity, a rotating part arranged in the shell, and a driving motor for driving the rotating part. The rotating speed of the driving motor is adjustable. A lower ice hole communicated with the ice particle outlet and a falling ice hole arranged in a staggered mode with the lower ice hole are arranged on the shell. In this way, the rotating speed of the rotating part is adjusted by controlling the rotating speed of the driving motor, the ice particle discharging amount is controlled, and the precision of the ice particle abrasive mixed conveying amount is improved.

This invention provides a rust removal device and method for cargo hold ribs, including a traveling drive mechanism, a traveling support mechanism, and a nozzle assembly. The nozzle assembly is mounted on the traveling support mechanism, which is connected to the traveling drive mechanism. The nozzle assembly includes a nozzle body and a rotating body. The nozzle body has at least two spray surfaces arranged at an angle, and several nozzles are arranged on the spray surfaces. The nozzle body has several nozzle channels that communicate with the nozzles for spraying water. The nozzle body is located at the end of the rotating body. In this invention, the nozzle body has at least two spray surfaces arranged at an angle. When the nozzle body removes rust, multiple spray surfaces can simultaneously impact and remove rust from the transverse and longitudinal surfaces of the cargo hold ribs, reducing costs compared to the use of multiple independent nozzles in the prior art.

This document provides a method for designing nozzles. [Solution] This is a nozzle design method suitable for designing a nozzle for surface modification of particulate matter, which includes sequentially connected shrinkage stage, throat stage, and diffusion stage. Computational fluid dynamics-discrete element method (CFD-DEM) software is used to simulate at least one nozzle size group over a range of particulate matter velocities to obtain the first to third coefficient ranges and a constant range for the nozzle size design equation, where V = a*X + b*Y + c*Z + d, where V is the particulate matter velocity, a, b, and c are the first to third coefficients, respectively, d is a constant, and X, Y, and Z are the maximum flow path diameters of the shrinkage stage, throat stage, and diffusion stage, respectively. Using the CFD-DEM software, calculations are performed using the nozzle size design equation with the first to third coefficient ranges, the constant range, and the target velocity to obtain the calculated nozzle size group.

The present application relates to the field of polishing equipment, disclose a kind of tungsten alloy plating infiltration oil pipe inner wall sand blasting polishing equipment, including machine body, lifting mechanism and multiple polishing mechanism, polishing mechanism includes fixture assembly, injection assembly and rotary component, injection assembly includes clamping block, air pipe, swivel pipe, sleeve and sealing pipe, sleeve is vertically fixedly sleeved in clamping block, and vertically set with spray hole, swivel pipe is vertically rotatably sleeved in sleeve, and vertically set with multiple storage cavities in inside, air pipe side portion vertically set with air hole, air hole is aligned with spray hole, spring is fixedly embedded in sealing pipe wall, sleeve is slidably sleeved in clamping plate, air pipe top end is connected with pneumatic mechanism, swivel pipe top end is connected with feeding mechanism, fixture assembly is set on lifting mechanism.The present application solves the problem that the equipment output caliber cannot be flexibly adjusted according to the polishing requirements of oil pipe, cannot realize sufficient polishing in single pass, and the polishing efficiency is low.

This invention relates to a fully automatic adhesive application and sandblasting device for porcelain insulators, belonging to the technical field of porcelain insulator processing equipment. It includes a base, a support frame, a rotating disk, a mounting column, positioning rods, a lifting frame, a first mounting frame, a second mounting frame, an adhesive application assembly, and a sandblasting assembly. The mounting column is mounted on the base, and the rotating disk is rotatably mounted on the outer periphery of the mounting column. The mounting column is equipped with a drive mechanism for rotating the rotating disk. The rotating disk has positioning holes. The mounting column is equipped with a flipping mechanism for opening the two positioning rods. The support frame is mounted on the base, and the lifting frame is slidably mounted on the support frame. The support frame is equipped with a second moving mechanism for moving the lifting frame vertically. Both the first and second mounting frames are slidably mounted on the lifting frame. Two adhesive application assemblies and two sandblasting assemblies are provided. This invention automatically positions the porcelain insulator, and after positioning, simultaneously applies adhesive and sandblasts the inner and outer walls of the porcelain insulator.

This invention provides an angle-adjustable rust removal device and method for inner compartments, including a support column, a first longitudinal roller, a second longitudinal roller, a transverse roller, a nozzle support base, an angle adjustment assembly, and a nozzle assembly. The first and second longitudinal rollers are both mounted on the support column, and their orientations are opposite. The first and second longitudinal rollers are respectively positioned in contact with the transverse surface of the inner compartment rib and the inner compartment wall panel. The transverse roller is mounted on the support column, and its orientation is perpendicular to that of the first longitudinal roller. The transverse roller is positioned in contact with the longitudinal surface of the inner compartment rib. This invention changes the orientation of the first and second nozzle assemblies through the angle adjustment assembly, enabling the inner compartment rust removal device to have rust removal functions in multiple directions, expanding its application range and improving rust removal efficiency.

The present invention relates to portable cavitation peening methods and devices. A method of cavitation peening can include coupling a movable water source to a portable nozzle through a flexible conduit. The method can include positioning the nozzle proximate to a treatment surface and discharging a first fluid stream and a second fluid stream through a first passage and a second passage of the nozzle, wherein the second passage is positioned concentrically around the first passage. The first stream can have a first pressure and the second stream can have a second pressure, the first pressure being greater than the second pressure and the two streams combining to create a cloud of cavitation bubbles.

The application discloses a flash removing device for tungsten alloy rods, which comprises a rotating disc, one side of the rotating disc is provided with a motor, the driving shaft of the motor is connected with a rotating shaft, and one end of the rotating shaft extends to the outside through the side wall of the rotating disc; a plurality of placing assemblies are arranged on the rotating disc, and a plurality of driving assemblies matched with the placing assemblies are arranged on the rotating disc. During use, when the motor works, the rotating disc can rotate, meanwhile, the feeding assembly and the conducting assembly can convey the semi-finished tungsten steel rods to the placing assemblies, then under the assistance of the driving assemblies, the tungsten steel rods can rotate, so that the tungsten steel rods can realize the functions of rotation and circumferential rotation, and meanwhile, when the external corundum particles are sprayed from the sand blasting assembly through compressed air, the tungsten steel rods can be passivated.

This invention provides a SED ecological descaling system for thin-gauge steel plates, designing a steel plate descaling technology field. High-pressure water and abrasive are mixed inside the descaling nozzle to form a high-pressure abrasive jet, which then impacts the steel strip surface. Relying on the impact grinding of the abrasive and the water wedge effect of the high-pressure water, the oxide scale and rust on the steel plate surface are removed. The continuous arrangement of four descaling units allows for full-width descaling coverage of the steel plate as it is conveyed, and the system is finished by a rinsing unit to improve the overall descaling effect. The wastewater and waste sand generated during descaling can be recycled and reused through a sand sorting and recovery system, a water circulation system, and a sand circulation system. This achieves graded recovery and recycling of the abrasive, and sedimentation, filtration, and reuse of the wastewater, significantly improving the abrasive recovery rate and wastewater reuse rate, realizing an ecological resource recycling descaling effect.

The utility model relates to a sand blasting gun head belongs to the technical field of spraying equipment, including sand blasting gun head body, the sand blasting gun head body is seted up in the mixing chamber, sand blasting gun head body installs the communicating pipe for the outside conveying sand's intercommunication, the sand blasting gun head body one side installs the gas connection pipe for the outside high pressure gas's intercommunication, the gas connection pipe one end and located the mixing chamber installs the nozzle, the communicating pipe intercommunication mixing chamber, sand blasting gun head body is installed with the mixed diffuser ware away from the nozzle one end, the utility model discloses a sand blasting gun head, through communicating pipe and gas connection pipe, convey sand and high pressure gas respectively, after mixing in the mixing chamber, then spray through mixed diffuser ware, guarantee the consistency and uniformity of sand blasting effect, and can drive sand blasting gun head swing through the movable device, the range of workpiece sand blasting is bigger.

The application discloses a kind of discharge driving abrasive flow processing microneedle die core dynamic and static process control method: S1 in the microneedle die core forming milling process, using PCD slope cutter, free abrasive liquid is added on workpiece, while programmable power supply anode is connected to microneedle die core, cathode is connected to milling cutter handle, and abrasive flow is formed in the gap between cutter and microneedle side face;Workpiece material is removed under the joint action of cutter and abrasive flow, and microneedle die core is formed;S2 effective pulse discharge energy is judged by discharge waveform, pulse discharge power is calculated and output to controller;S3 closed-loop feedback control is realized by controller during processing, and dynamic and static stability of control abrasive removal force in the gap between cutter and workpiece surface is realized.The application can effectively improve the machining precision of microneedle die core and reduce needle tip radius by controlling the processing of microneedle die core.

The utility model provides a kind of shot blasting machine of convenient material taking, including base and throw head, wherein: the base is fixedly installed with baffle one and baffle two, and form a U-shaped cavity with baffle one and baffle two between, the base is fixedly installed with electric turntable assembly, the electric turntable assembly is uniformly fixedly installed with several groups of paired baffle for plugging the both sides of U-shaped cavity, the electric turntable assembly is uniformly rotatably installed with several material hangers, the material hanger is between corresponding paired baffle;The overall setting of the utility model, whether material taking or discharging, does not need to open and close shot blasting protective door, so that the overall process of material taking and discharging is more convenient and efficient.

This utility model relates to the field of lampshade production, and more particularly to a surface treatment device for aluminum parts of lampshades before spraying. It includes a main chamber, a conveyor belt, and an installation platform. Transport troughs are provided at both ends of the main chamber. A conveyor belt is installed at the lower end of the transport trough, and an installation platform is installed on the right side of the outer surface of the conveyor belt. A first motor is installed at the lower end of the installation platform, and a first drive shaft is rotatably connected to the upper left side of the installation platform. The output end of the first motor is connected to the lower end of the first drive shaft. This utility model, by setting up a first motor, drives the first drive shaft and the first active disc to rotate. After the rotation support module is in contact with the first active disc, it drives the lampshade to rotate. A second motor drives a lead screw to rotate, and a lifting frame restricts the rotation of the connecting plate, causing it to shift and move a sponge brush downwards to perform circumferential cleaning on the surface of the rotating lampshade. After completion, the brush is reset to avoid interfering with the operation of the conveyor belt, thus achieving pre-cleaning of the lampshade surface.

The application discloses a pipeline inner wall pretreatment system and relates to the technical field of pipeline inner wall processing. The pipeline inner wall pretreatment system comprises a main pipe, a supporting part, a cleaning assembly, a air-drying assembly and a traction device. The supporting part is arranged on the main pipe and is used for cooperating in a pipeline to be processed to separate the inner cavity of the pipeline to be processed. The cleaning assembly comprises a first nozzle used for spraying cleaning materials. The air-drying assembly comprises a second nozzle used for spraying gas. The first nozzle and the second nozzle can rotate around the axis of the main pipe to perform circumferential processing on the inner wall of the pipeline to be processed. The traction device is connected with the front end of the main pipe and is used for driving the main pipe to move along the axial direction of the pipeline to be processed in the pipeline to be processed. The pipeline inner wall pretreatment system can safely and efficiently clean and process the inner wall of the pipeline and guarantees the rust-proof effect of the inner wall of the pipeline.

The application discloses a centrifugal pump spiral flow channel shell structure integrated with wear-resistant coating and a manufacturing method thereof, relates to the technical field of surface protection of centrifugal pumps, and aims at the problems of easy wear, corrosion and fluid loss of the existing centrifugal pump shell under the scouring of high-speed fluid and solid particles. The application integrates a multilayer composite wear-resistant coating on the inner surface of the spiral flow channel shell, and the coating is sequentially composed of a base layer, a reduced graphene oxide reinforced layer, an intelligent thermal response layer, a self-repairing nano coating and a surface functional coating. The reduced graphene oxide reinforced layer significantly improves the hardness and thermal conductivity of the coating; the intelligent thermal response layer adopts a nickel-titanium alloy powder to realize self-adaptive hardness adjustment according to temperature; the self-repairing nano coating encapsulates a repairing agent through microcapsules to realize self-healing of microcracks; and the surface functional coating is modified by nano particles to regulate fluid behavior. The wear resistance, corrosion resistance, thermal stability and self-repairing capability of the centrifugal pump shell are improved, the service life of the equipment is prolonged, and the maintenance cost is reduced.

This application discloses a continuous production equipment for ion exchange membranes used in vanadium batteries, relating to the field of ion exchange membranes. It includes an operating table and a clamping mechanism at the top of the operating table for holding the ion exchange membrane. A motor is provided on one side of the clamping mechanism to provide driving force. Inside the clamping mechanism is a cutting mechanism for cutting the ion exchange membrane while it is being held. This application achieves intermittent stable clamping by driving the clamping block to close, which is fixed in two directions. This is linked to the rotation of a reciprocating screw, and with the assistance of a sensor, the water jet nozzle performs non-contact cutting of the ion exchange membrane, eliminating edge burrs from mechanical blades and dimensional deviations caused by tool wear. Since the cutting is performed while the ion exchange membrane is completely clamped and fixed, vibration or displacement during cutting is avoided, ensuring cutting dimensional accuracy and improving the production efficiency of the ion exchange membrane.

The utility model relates to a kind of cutting fluid polishing devices, belong to the technical field of valve parts processing equipment, it includes liquid storage, input pipeline and driving part, liquid storage is hollow inside, cutting fluid is placed inside, cutting fluid contains polishing particle, input pipeline is arranged between liquid storage and the part to be processed, it extends to the part to be processed direction in one end, other end is inserted into liquid storage until its end is in cutting fluid, driving part is arranged on input pipeline, for cutting fluid in liquid storage is inhaled into input pipeline, and cutting fluid in input pipeline is injected into the part to be processedThe utility model has thoroughly removed the scrap iron remaining in the part to be processed, polish the inside of the part to be processed at the same time, inhibit the metal powder of the inner surface of the part to be processed from falling off, prevent medium pollution and accident, realize the effect of chip removal and polishing synchronous processing.

The utility model relates to the technical field of shot blasting machine strength adjustment, and disclose a kind of shot blasting machine shot blasting strength adjusting device, including shot blasting machine body, the side fixedly connected with feed pipe of shot blasting machine body, the inside of feed pipe is provided with several groups of buffer component, the bottom surface fixedly connected with fixed box of shot blasting machine body, the inside of fixed box is provided with adjusting component, several groups of buffer component all include the buffer plate of being arranged in feed pipe inside, the outside of several groups of buffer plate is all fixedly connected with two groups of first rotary rod.The shot blasting machine shot blasting strength adjusting device, by the setting of adjusting component, in use, start servo motor, servo motor rotates and drives second rotary rod to rotate, second rotary rod rotates and drives baffle to rotate, so that the opening size between baffle and shot blasting machine body pellet outlet is adjusted, to change the throughput of shot blasting medium in unit time, realize the accurate control to shot blasting strength.

The utility model relates to mechanical processing technical field discloses a kind of metal workpiece sand blasting devices for machining, including processing box, and the upper end of processing box is fixedly installed with air pump and sand storage tank, and the input end of air pump is connected with sand storage tank, and the output end of air pump is fixedly installed with conveying pipe, and the outer surface of conveying pipe is sleeved with heating electric wire, and the outer surface of heating electric wire is equipped with heat insulation tube, and heat insulation tube is fixedly installed on the outer surface of conveying pipe, and the upper end of heat insulation tube is fixedly installed with sleeve pipe, and the inside lateral wall of sleeve pipe is fixedly installed with fan, technical effect is to solve sand blasting process pain point under low temperature environment, while, low cost, high reliability and strong adaptability are considered, efficient practical technical scheme is provided for metal workpiece sand blasting pretreatment.

The utility model relates to a kind of shot blasting machine discharging device, including discharging bin, and the upper part of the top and bottom of discharging bin is equipped with upper material port and lower material port respectively, and the side of discharging bin is equipped with observation window.The first baffle of manually pulling out and inserting is configured below upper material port to control the opening and closing of feeding, and the second baffle extending to the rear end of bin body is arranged above lower material port, and the movable end of the baffle is connected with the pneumatic valve outside bin.The extension length of pneumatic valve can be controlled by motor, the covering range of second baffle to lower material port can be accurately adjusted, and then the fine and rapid control of shot blasting machine shot supply flow is realized.

This technology provides the ability to detect nozzle abnormalities before they affect machining accuracy. [Solution] The shot processing device 1 comprises a hopper 3 for storing the propellant 2, a nozzle 4 for injecting the propellant 2, which has been sucked in by negative pressure, together with compressed air, a transport path for transporting the propellant 2 from the hopper 3 to the nozzle 4, a compressor 6 for supplying compressed air to the nozzle, a negative pressure gauge 7 for detecting the pressure in the transport path, and an abnormality detection unit 52 for detecting an abnormality in the nozzle 4 based on the detection result of the negative pressure gauge 7.