Nozzle assembly of a pneumatic dental sandblasting device

Abstract

The purpose of this invention is to provide a nozzle assembly for a pneumatic dental air blasting device with reduced processing costs and a processing method thereof. A nozzle assembly for a pneumatic dental air blasting device includes a housing, a gas pipe, a water pipe, and a nozzle, with the gas pipe and water pipe respectively fixed to the nozzle; one end of the housing is connected to the nozzle, and the other end is a connector; the housing has a water inlet for the water pipe; the housing includes an outer shell and an inner frame, with the inner frame inside the outer shell; the connector is located at one end of the inner frame, and the gas pipe passes through the other end of the inner frame and is locked; the combination of the gas pipe and the inner frame locks the nozzle, the outer shell, and the inner frame.

Description

Technical Field

[0001] The invention relates to the field of dental medical instruments, in particular to a nozzle assembly of a pneumatic dental sandblasting device. Background Art

[0002] Teeth cleaning is a good way to maintain dental health and is also the primary measure to treat periodontal disease. Regular teeth cleaning can not only completely remove dental plaque and calculus on teeth, keep periodontal tissue healthy, and prevent periodontal disease. In addition, teeth cleaning can easily detect small, difficult-to-detect dental diseases, such as hidden caries, to achieve the purpose of early detection and early treatment.

[0003] Sandblasting is a method of cleaning teeth by using pearl salt and high-pressure water to clean tea stains, cigarette stains and physical soft scale attached to the teeth. The teeth after sandblasting are very smooth and not prone to tartar deposition again. Therefore, it is usually recommended to combine teeth cleaning and sandblasting.

[0004] The pneumatic dental sandblasting device processes teeth by jetting abrasive powder mixed with air and water. The pneumatic dental sandblasting device comprises a body assembly and a nozzle assembly, and the body assembly and the nozzle assembly are plug-in connected;

[0005] The machine body assembly includes an integrated powder container (also called a sand chamber) for storing a predetermined amount of powder, an air supply line for pressurizing air and connected to the powder container, a transmission line for conveying powder mixed with air, a water supply line connected to a water source, and a machine body joint connected to a nozzle; one end of the transmission line is connected to the powder container, and the other end is exposed to the machine body joint; a water flow outlet of the water supply line is opened at the machine body joint, and there are two sealing rings in the axial direction of the machine body joint, and the water flow outlet is between the two sealing rings;

[0006] The nozzle assembly includes a nozzle housing, a nozzle, a water output line and an air powder output line. The nozzle has a water channel and an air powder channel, and the air powder channel is inside the water channel; the nozzle has a water flow inlet of the water output line and a gas inlet of the air powder output line, and the nozzle housing is sealed and connected to the body joint; when the head assembly and the nozzle assembly are connected, the transmission line is connected to the air powder output line.

[0007] When the sandblasting machine is in use, the body assembly and the nozzle assembly are plugged into place, and a water-containing gap is formed in the area between the two sealing rings; pressurized air and water are input, and air powder is sprayed out from the air powder channel through the transmission line and the air powder output line, and water is sprayed out from the water channel through the water supply line, the water-containing gap and the water output line.

[0008] The current sandblasting machine has the following shortcomings: 1. The body joint and the part connected to the body joint inside the nozzle shell are made of metal materials, which has high manufacturing costs. After repeated plugging and unplugging, the metals wear each other, resulting in loose connections between the body assembly and the nozzle assembly. 2. After multiple plugging and unplugging of the transmission line and the air powder output line, the sealing of the connection decreases, which is prone to sand leakage and sand blockage. 3. The water channel is annular, the water flow is scattered in annular shape, and the spray force is relatively small. Summary of the invention

[0009] The object of the present invention is to provide a nozzle assembly of a pneumatic dental sandblasting device with reduced processing cost and a processing method thereof.

[0010] A nozzle assembly of a pneumatic dental sandblasting device comprises a shell, a gas pipeline, a water pipeline and a nozzle, wherein the gas pipeline and the water pipeline are respectively fixed to the nozzle; one end of the shell is connected to the nozzle and the other end is a joint; the shell has a water inlet of the water pipeline.

[0011] The joint part seals the nozzle assembly and the body assembly to form a workable sandblasting machine. After the nozzle assembly and the body assembly are connected, the water pipe water outlet of the body assembly and the water pipe water inlet of the nozzle assembly are connected through a sealed cavity or space, so that the water flow is transported from the body assembly to the nozzle assembly and then sprayed out by the nozzle. After the nozzle assembly and the body assembly are sealed, the gas pipeline of the body assembly is sealed with the gas pipeline of the nozzle assembly, and the powder-air mixture is transported from the body assembly to the nozzle assembly and then sprayed out by the nozzle. The jet port in the nozzle is inside and the water outlet is outside the jet port.

[0012] case

[0013] As a preferred solution, the shell and the nozzle are detachably matched, the gas pipeline has a threaded section, the shell has a baffle, the gas pipeline passes through the baffle and is locked, and the combination of the gas pipeline and the shell locks the nozzle and the shell.

[0014] As a preferred solution: the shell includes an outer shell and an inner frame, the inner frame is inside the outer shell; one end of the inner frame is a joint part, and the other end is a baffle, the gas pipeline passes through the other end of the inner frame and is locked, and the combination of the gas pipeline and the inner frame locks the nozzle, the outer shell and the inner frame. The gas pipeline of the nozzle assembly passes through the connecting end of the inner frame to communicate with the gas pipeline of the body assembly. The outer shell, the inner frame and the nozzle are three independent components, and when the gas pipeline and the inner frame are locked, the inner frame, the outer shell and the nozzle are combined together.

[0015] As a preferred solution, the inner frame includes a barrel, a joint portion is provided at a first end of the barrel, and a baffle is provided at a second section opposite to the first end, wherein the baffle has a through hole allowing the gas pipeline to pass through.

[0016] Preferably, a locking piece is provided inside the frame, and the locking piece is tightly matched with the gas pipeline. Preferably, the locking piece and the gas pipeline are locked by an inclined surface, keyed, etc.

[0017] Preferably, the nozzle assembly has a locking piece, which abuts against the baffle of the inner frame, and the locking piece is fastened to the gas pipeline through a threaded pair, or the locking piece is tightly matched with the gas pipeline; the gas pipeline has a connection end that exposes the locking piece. This locking piece is a part independent of the inner frame. During assembly, after the gas pipeline passes through the baffle of the inner frame, it is connected to the gas pipeline with the locking piece. When the locking piece abuts against the inner frame, it indicates that the locking piece and the gas pipeline are connected in place. Preferably, the locking piece is a nut, and a threaded section is provided on the gas pipeline. The nut meshes with the threaded section. The inner frame and the gas pipeline are locked with the locking piece, so that the nozzle, the outer shell and the inner frame are combined into a nozzle assembly. During assembly, the nozzle assembly can be disassembled by loosening the locking piece, which is convenient for maintenance and replacement of parts.

[0018] As a preferred solution, the water inlet of the water pipeline is arranged on the inner frame, and there is a sealing ring between the inner frame and the water pipeline. The water pipeline is bent to avoid the inner frame, and a part of the water pipeline is located between the inner frame and the outer shell. In addition to preventing water from entering the area between the inner frame and the outer shell, the sealing ring also plays a positioning role for the water pipeline and fixes one end of the water inlet of the water pipeline. Preferably, the barrel of the inner frame has a receiving portion for accommodating the water pipeline, and the receiving portion is a notch opened on the surface of the barrel, or the receiving portion is a hole opened on the barrel, and the receiving portion is connected to the water inlet. The receiving portion plays a limiting role on the water pipeline, and finally the water inlet end of the water pipeline is fixed by the sealing ring.

[0019] As a preferred solution, the outer surface of the inner frame is provided with a first step, and the inner surface of the outer shell is provided with a second step matching the first step; the second step is closer to the nozzle relative to the first step. As the locking member is combined with the gas pipeline, the first step presses against the second step to move the outer shell toward the nozzle. Preferably, both the first step and the second step are annular steps.

[0020] Preferably, a positioning rib is provided in the outer shell, the positioning rib is in contact with the inner frame, and the positioning rib is at a distance from the first step. When the inner frame, the outer shell and the nozzle are combined, the positioning rib and the inner frame are pressed against each other to prevent the inner frame, the gas pipeline and the water pipeline from shaking. Preferably, there are multiple positioning ribs, and the multiple positioning ribs are evenly arranged around the inner frame. Preferably, the barrel of the inner frame is cylindrical, and the surface where the positioning rib contacts the inner frame is arc-shaped. Thereby, the contact area between the inner frame and the positioning rib is increased, and the stability of the inner frame positioning is improved.

[0021] As a preferred mode, the shell and the nozzle are detachable independent components. In this way, the shell, the inner frame and the nozzle are independent parts, which can be replaced separately, making it easy to repair and replace parts, and the parts can be manufactured separately, simplifying the structure of a single part and reducing the manufacturing cost.

[0022] Preferably, one end of the shell is against the nozzle, and a stopper is provided between the joint surface of the shell and the nozzle to prevent the shell and the nozzle from rotating relative to each other. Thus, after the shell and the nozzle are combined, there is no rotational displacement between the shell and the nozzle, and the stability of the nozzle assembly is maintained.

[0023] In another preferred embodiment, the housing and the nozzle are fixedly connected, or the housing and the nozzle are integrated. The housing and the nozzle are fixedly connected or integrated, which simplifies the assembly process and increases the reliability of the connection between the housing and the nozzle.

[0024] Circlip

[0025] When the nozzle assembly and the machine body assembly are combined, there is a C-shaped retaining spring between the nozzle assembly and the machine body assembly, and the deformation of the retaining spring is used to realize the clamping connection between the nozzle assembly and the machine body assembly.

[0026] As a preferred solution, a C-shaped retaining spring is provided between the nozzle assembly and the body assembly, and the two ends of the retaining spring are passivated. If the ends are spherical, curved, chamfered, etc., they are all passivated ends.

[0027] Preferably, the retaining spring is installed at the joint of the inner frame, and a retaining spring groove matching the retaining spring is arranged on the body assembly.

[0028] Preferably, each end of the circlip is inclined, and the inclined surface faces the body component. The inclined surface faces the body component, and the inclined surface forms an obtuse angle with the inner ring of the circlip. The inner ring is the one with a smaller diameter, and the outer ring is the one with a larger diameter. The inclined surface reduces the wear between the circlip and the body component.

[0029] Preferably, the edge of the bevel is a smooth curved surface. When both ends of the retaining spring are smooth curved surfaces such as ball heads and arc surfaces, there is no cutting between the retaining spring and the body assembly, so when the nozzle assembly and the body assembly are plug-in connected, the retaining spring and the body assembly can avoid mutual wear.

[0030] nozzle

[0031] The water and air mixture is sprayed out from the nozzle, the nozzle is connected to the water pipeline and the gas pipeline respectively, and the nozzle is fixed to the shell.

[0032] As a preferred solution, the nozzle includes a body and a nozzle tube. The nozzle is connected to a water pipe and a gas pipe respectively. The nozzle has a water spray channel and an air jet channel. The air jet channel is inside and the water spray channel is outside the air jet channel. The body and the nozzle tube are tightly matched. There is a water spray channel inside the nozzle tube. There is a water inlet and a water guide between the nozzle tube and the body. The water inlet and the water guide are connected to form a water spray channel. The nozzle tube is fitted with the body except for the water inlet and water spray channel. Water can only be sprayed out from the outlet of the water spray channel, so that fixed-point and uniform water discharge is achieved and the force of water spraying outward is increased.

[0033] Preferably, there are multiple water guides, the outlets of the water guides serve as outlets of the water jet channel, and the outlets of the multiple water guides are evenly distributed around the jet channel.

[0034] Preferably, the body of the nozzle has a water pipe connecting channel and an air pipe connecting channel, the water pipe connecting channel is fixed to the water pipeline, and the air pipe connecting channel is fixed to the gas pipeline.

[0035] Preferably, the body of the nozzle has a nozzle pipe mounting hole, the nozzle pipe is inserted into the nozzle pipe mounting hole, and the nozzle pipe is tightly matched with the body.

[0036] Preferably, the nozzle body is molded by MIM injection molding, and the water pipe connection channel, the gas pipe connection channel and the steel pipe receiving cavity are formed during the injection molding. After the MIM injection molding of the body is completed, the water pipe is connected to the water pipe connection channel by laser welding, the gas pipe is connected to the gas pipe connection channel by laser welding, and the nozzle pipe is pressed into the steel pipe receiving cavity, and the nozzle pipe and the body are interference fit.

[0037] In other embodiments, the nozzle has a connector, which has an air pipe interface, a water pipe interface and a nozzle pipe interface. The air pipe interface and the water pipe interface are respectively connected to the nozzle pipe interface, and the connecting part between the air pipe interface and the nozzle pipe interface is staggered with the connecting part between the water pipe interface and the nozzle pipe interface.

[0038] When making the nozzle, the nozzle tube is fixed in the nozzle tube interface, and there is an air inlet and a water inlet between the nozzle tube and the nozzle tube interface. The air inlet is connected to the air pipe interface and the jet channel, and the water inlet is connected to the water pipe interface and the water spray channel. After the connector is connected to the water pipe, gas pipe, and nozzle tube, the nozzle body is injection molded. The nozzle tube is fitted with the body except for the water spray channel. Water can only be sprayed out from the water spray channel, achieving fixed-point and uniform water discharge and increasing the force of water spraying outward.

[0039] In other embodiments, the gas pipeline, water pipeline and nozzle tube are wrapped around the nozzle body, the gas pipeline is provided with a mounting hole, the nozzle tube is inserted into the mounting hole, and the gas pipeline is connected with the jet channel; the water pipeline is provided with a water spray outlet that runs through the water pipeline, the nozzle tube passes through the water spray outlet and the water spray outlet is aligned with the water inlet.

[0040] When making the nozzle, the nozzle tube is passed through the water outlet of the water pipe and then inserted into the mounting hole of the gas pipe, and then the nozzle is injection molded. The area of ​​the nozzle tube except the water inlet channel is fitted with the body, and water can only be sprayed out from the water outlet channel, thereby achieving fixed-point and uniform water discharge and increasing the force of the water spraying outward.

[0041] As a preferred solution, the nozzle has an extension section connected to the shell, and a positioning step is formed between the extension section and the nozzle. As long as there is a size change between the nozzle and the extension section, the positioning step can appear. When the shell abuts against the positioning step, it means that the shell and the nozzle are in place.

[0042] Preferably, the stopper is arranged between the extension section and the shell, the extension section is inserted into the shell, the stopper is a protrusion and a groove matching each other, the protrusion is located in the extension section and the groove is located in the shell, or the protrusion is located in the shell and the groove is located in the extension section. When the protrusion is inserted into the groove, the rotational freedom of the nozzle and the shell is unified.

[0043] Preferably, the protrusion is a rectangular block, and the recess is a rectangular groove.

[0044] Preferably, there are multiple limiting members, and the multiple limiting members are evenly distributed between the shell and the extension section.

[0045] Nozzle pipe

[0046] The mixture of powder and air is sprayed out from the inner cavity of the nozzle tube, and the water flow is sprayed out from between the nozzle tube and the nozzle.

[0047] As a preferred solution, the nozzle tube is in a hollow cylindrical shape, and is provided with an air inlet, a water inlet and a water guide. The air inlet is connected to the inner cavity of the nozzle tube, and the water inlet and the water guide are isolated from the inner cavity of the nozzle tube. The water inlet is located between the water pipe and the water guide. The inner cavity outlet of the nozzle tube serves as the jet outlet of the nozzle, and the outlet of the water guide serves as the water spray outlet of the nozzle. When the nozzle tube is matched with the nozzle body, the water inlet and the water guide cooperate with the nozzle body to form a water spray channel, and the water inlet serves as the entrance of the water spray channel.

[0048] The water inlet part divides the pipe body into an air pipe connecting section and a water diversion section, the air inlet hole is located in the air pipe connecting section, and the water diversion part is located in the water diversion section.

[0049] Preferably, the water guide part is arranged along the axial direction of the nozzle tube, there are multiple water guide parts, and the multiple water guide parts are evenly distributed along the circumference of the nozzle tube. The part of the water guide section other than the water guide part is in contact with the nozzle, and the water flow is concentrated and sprayed outward from the water guide part, thereby increasing the force of the water flow spraying and spraying evenly and at a fixed point.

[0050] Preferably, the water guide portion is a groove formed on the surface of the nozzle tube. The cross-sectional shape of the water guide portion is rectangular, semicircular, arc-shaped, V-shaped, U-shaped, L-shaped, trapezoidal, etc.

[0051] Alternatively, the water guide is located in the water guide section, the water guide section is prismatic, the side of the water guide section serves as the water guide, and the water guide section is inscribed with the outer circle of the nozzle tube. Preferably, the water guide section is a regular prism. Preferably, the edges of the water guide section are rounded. The prismatic water guide section is easy to process, and the single-point water output is stable and large. Preferably, the nozzle tube is a cylinder with equal outer diameter, and the water inlet is a circle of concave rings opened on the outer surface of the nozzle tube. Preferably, the end of the water guide section is provided with an extension section, the extension section is a cylindrical ring, and the extension section is smaller than the tube body. Therefore, there is a circular ring gap between the extension section and the nozzle, and the water flows out of the fixed point of the water guide section and converges into a ring at the extension section. When the nozzle is in use, the water flows of all the guide grooves converge into a beam and then spray out. The length of the extension section does not consume the force of the water flow spraying, and can make the water flow converge into a beam and spray out.

[0052] Preferably, the tube body of the nozzle tube is interference fit with the steel tube connecting channel of the connector, the air pipe connecting section and the water inlet are located inside the connector, and the water guide section is partially exposed outside the connector.

[0053] Gas pipeline

[0054] The gas pipeline of the nozzle assembly is connected to the gas pipeline of the body assembly to form a conveying line for conveying the powder-air mixture.

[0055] Preferably, one end of the gas pipeline is fixed to the nozzle, and the other end is a connecting section for connecting to the body assembly. The gas pipeline has a locking portion that is fastened to the shell, and the locking portion is adjacent to the connecting section.

[0056] Preferably, the locking portion is an external thread. A nut is inserted into the housing, and the nut is meshed with the locking portion to achieve the purpose of locking the gas pipeline and the housing.

[0057] Preferably, the gas pipeline includes a pipe body and a connector, the connector is fixed to the pipe body, and the locking portion and the connecting section are arranged on the connector. The connector and the pipe body are combined into a gas pipeline, and the pipe body can still use the existing gas pipeline, and only the locking portion (such as tapping external threads) needs to be processed on the connector to reduce the manufacturing cost.

[0058] Preferably, the locking portion of the connector is enlarged relative to the connecting section. In this way, a limiting step can be formed between the connecting section and the locking section. The limiting step can be an inclined surface. When the connecting section is matched with the body assembly, locking is achieved by the inclined surface at the limiting step.

[0059] Anti-clogging sandblasting machine

[0060] The sandblasting machine includes a body assembly and a nozzle assembly. The nozzle assembly and the body assembly have their own gas pipelines respectively. A sealing cylinder is arranged between the gas pipeline of the nozzle assembly and the gas pipeline of the body assembly. The sealing cylinder is sealed and connected to the two gas pipelines respectively. There is a gap between the two gas pipelines. The common connection method between the body assembly and the nozzle assembly is a plug-in connection.

[0061] The gas pipeline of the nozzle assembly is sealed and connected to the sealing cylinder, and the gas pipeline of the body assembly is also connected to the sealing cylinder. The sealing cylinder serves as an intermediate cavity to connect the two gas pipelines. The sealing cylinder is in the shape of a tube with openings at both ends, and both ends of the sealing cylinder are respectively provided with connection parts that seal with the two gas pipelines. As a preferred solution, there is a transition cavity between the gas pipeline of the nozzle assembly and the gas pipeline of the body assembly, and the transition cavity is the inner cavity of the sealing cylinder. The outlet of the transition cavity is connected to the gas pipeline of the nozzle assembly, and the inlet of the transition cavity is connected to the gas pipeline of the body assembly. The so-called connection refers to that when the airflow enters the transition cavity from the gas pipeline of the body assembly, the transition cavity does not block the airflow, and when the airflow enters the gas pipeline of the nozzle assembly from the transition cavity, the gas pipeline of the nozzle assembly does not block the airflow.

[0062] As a preferred solution, both ends of the sealing cylinder are respectively provided with connecting parts that seal with two gas pipelines, one of which is a fixed end connecting part, and the other is a plug-in end connecting part. The fixed end connecting part has a groove, and the gas pipeline connected to the fixed end connecting part is provided with a protrusion that can be embedded in the groove; the plug-in end connecting part is a cavity that tightly fits with the other gas pipeline.

[0063] Preferably, the outer end of the plug-end connection portion is provided with a guiding slope.

[0064] Preferably, the sealing tube is a tube body made of wear-resistant elastic materials such as a silicone tube, a latex tube or a rubber tube.

[0065] Preferably, the fixed end connection part is connected to the gas pipeline of the body assembly, and the body assembly has a protective shell that wraps the sealing cylinder therein; the plug-in end connection part is connected to the gas pipeline of the nozzle assembly. The protective shell and the gas pipeline sandwich the sealing cylinder between them, so that the sealing cylinder has both flexibility to achieve a sealed connection when plugged into the gas pipeline of the nozzle assembly, and rigidity to avoid connection failure caused by deformation of the sealing cylinder.

[0066] Preferably, a guiding inclined surface is provided on the plug-in end connection portion. The guiding inclined surface matches the above-mentioned limiting step, and when the gas pipeline is inserted into place, the limiting step and the guiding inclined surface are close to each other. The contact area of ​​the two inclined surfaces increases, thereby improving the reliability of the seal.

[0067] Alternatively, the fixed end connection portion is connected to the gas pipeline of the nozzle assembly, and the plug-in end connection portion is connected to the gas pipeline of the body assembly.

[0068] Sandblasting Machine

[0069] During the use of the sandblasting machine, the nozzle assembly and the machine body assembly need to be able to rotate freely relative to each other. Therefore, the joint of the nozzle assembly and the joint of the machine body assembly must meet the concentricity requirements after assembly to ensure the smoothness of rotation.

[0070] The pneumatic dental sandblasting machine comprises a nozzle assembly and a body assembly. The body assembly is provided with a step, and the nozzle assembly is provided with a matching surface matching with the step. The step or the step surface is a plastic part.

[0071] As a preferred solution, there are multiple steps, which are concentric; each step corresponds to a mating surface. Preferably, there are two steps. The two concentric steps support the cooperation between the nozzle assembly and the body assembly, and the nozzle assembly and / or the body assembly rotate around the axis with the center line of the two steps as the axis. This ensures that during the working process, the sand cavity of the body assembly is always facing upward, and the air-powder mixture can be smoothly transported.

[0072] As a preferred solution, a sealing ring for sealing water flow is provided on the body assembly, and the sealing ring is located between the two concentric steps. In other words, the two concentric steps have a certain span, which increases the concentric matching area of ​​the body assembly and the nozzle assembly.

[0073] As a preferred solution, the step is a tapered step and the matching surface is a slope.

[0074] As a preferred solution, the mating surface of the nozzle assembly is provided at the joint portion of the nozzle assembly, the step of the body assembly is provided at the joint portion of the body assembly, the joint portion of the nozzle assembly is a plastic part, and the joint portion of the body assembly is an integrally formed metal part. The joint portion of the aforementioned nozzle assembly is located in the inner frame, the inner frame is independent of the outer shell, the inner frame can be a plastic part, and therefore the joint portion is a plastic part. At this time, the joint portion of the body assembly only needs to be integrally formed into two concentric steps. By integrally forming two concentric steps, the direct concentricity of the two steps is reliable and easy to process.

[0075] Alternatively, the mating surface of the nozzle assembly is a metal part, and the step of the body assembly is a plastic part. Preferably, the body assembly includes a metal joint body and a plastic collar, each plastic collar forms a step, and the plastic collar is fixed to the joint body. The plastic collar is fixed to the joint body by interference fit, bonding, thermoplasticization or injection molding.

[0076] When the joint of the nozzle assembly and the joint of the body assembly are both metal parts, in order to avoid severe wear caused by direct contact between the metal surfaces, two plastic collars are set at the joint of the body assembly. The plastic collars are in contact with the joint of the nozzle assembly, and there is a gap between the joint of the body assembly except for the plastic collars and the joint of the nozzle assembly. In this way, the direct wear of the two metal surfaces and the increase in concentricity are avoided.

[0077] Sand blasting machine sand chamber

[0078] As a preferred solution, a maximum powder adding amount marking line is provided in the sand chamber of the sandblasting machine, which can indicate the maximum amount of powder added by the customer.

[0079] As a preferred solution, there are pressurized air delivery pipes and gas pipelines in the sand cavity, the pressurized air delivery pipeline 14 has an air outlet, and the gas pipeline has an air powder inlet; the marking line is lower than the air outlet and the air powder inlet. This prevents the powder (sand powder) from entering the pressurized air delivery pipeline 14 and the gas pipeline due to the customer adding too much powder, causing sand blockage.

[0080] Preferably, the inner surface of the sand cavity is spherical.

[0081] Preferably, the body assembly of the sandblasting machine is provided with a mounting portion of the sand chamber, the sand chamber is embedded in and fixed to the mounting portion, and the sand chamber has a top edge higher than the mounting portion; the sandblasting machine has a sand chamber cover, the mounting portion has a connecting portion that cooperates with the sand chamber cover, and the sand chamber cover has a sealing ring. After the sand chamber cover and the mounting portion are connected in place, the sealing ring is pressed between the sand chamber cover and the top edge. The top edge of the sand chamber is higher than the mounting portion, so as to prevent the powder in the sand chamber from falling into the gap at the connection between the sand chamber and the mounting portion.

[0082] Preferably, the air outlet of the pressurized air delivery pipe 14 and the air powder inlet of the gas pipe are lower than the top edge of the sand cavity. The air outlet and the air powder inlet are located inside the sand cavity, which is conducive to the pressurized air dispersing all the powder (or sand powder) in the sand cavity, so that the powder filled each time can be used up, thereby improving the exhaustion rate of the pre-loaded powder in the sand cavity.

[0083] Preferably, the sand cavity has an outer ring edge extending outward, and the mounting portion is within the area covered by the outer ring edge. In this way, the sand cavity completely covers the connection between the sand cavity and the mounting portion, and when adding powder, the powder will not fall into the connection area between the sand cavity and the mounting portion. Preferably, the mounting portion and the sand cavity cover are connected by a threaded pair.

[0084] Preferably, the sand cavity cover has a transparent window, and the marking line is within the visible range of the window.

[0085] The advantages of the present invention are as follows: 1. The outer shell, the inner frame and the nozzle are three independent parts, which can be manufactured separately with different materials, thereby reducing the manufacturing cost. 2. The inner frame can be made of plastic material, and the joint part is also a plastic part. The plastic joint part of the nozzle assembly is plug-in connected with the metal body assembly, and the self-lubrication and wear resistance of the plastic material are utilized to reduce the wear between the nozzle assembly and the body assembly. 3. The end of the retaining spring is passivated to avoid or reduce the wear between the retaining spring and the body assembly and the nozzle assembly, thereby extending the service life of the precise combination of the body assembly and the nozzle assembly. 5. The nozzle directional guides the water flow through the water guide part, so that the sprayed water flow is uniform and the force is concentrated. 6. A sealing cylinder is arranged between the gas pipeline of the body assembly and the gas pipeline of the nozzle assembly, and the sealing cylinder is respectively sealed and connected with the two gas pipelines, so that the two gas pipelines are not in direct contact, and there is no wear between the gas pipelines; the gas pipeline is a rigid part, and the sealing cylinder is a flexible part. The sealing cylinder has good wear resistance and is not easy to deform, thereby increasing the number of plug-in times of the nozzle assembly and the body assembly; the service life of the sandblasting machine is extended, and sand leakage and blockage are ensured. 7. The body assembly and the nozzle assembly are matched through concentric steps, and the body assembly and the nozzle assembly can rotate smoothly relative to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Figure 1 is a schematic diagram of the nozzle assembly.

[0087] Figure 2 yes Figure 1 sectional view of .

[0088] Figure 3 This is a schematic diagram of the inner frame.

[0089] Figure 4 It is a schematic diagram of the location of the water outlet on the body component.

[0090] Figure 5 Schematic diagram of the shell, wherein (a) is the main view of the shell, (b) is the AA cross-sectional view of (a), (c) is the shell from one perspective, and (d) is the shell from another perspective.

[0091] Figure 6 It is a three-dimensional diagram of the nozzle.

[0092] Figure 7 A cross-sectional view of a nozzle.

[0093] Figure 8 It is a cross-sectional view of a second nozzle with a connecting piece.

[0094] Fig. 9 It is a cross-sectional view of the third type of nozzle.

[0095] Fig.10Schematic diagrams of nozzle tubes, wherein (a) is a schematic diagram of a nozzle tube of one structure, (b) is a schematic diagram of a nozzle tube of a second structure, and (c) is a schematic diagram of a nozzle tube of a third structure.

[0096] Fig.11 This is a schematic diagram of the circlip.

[0097] Fig.12 2 are comparison diagrams of water flow spraying of nozzles, wherein (a) is a water flow spraying diagram of a nozzle of the prior art, and (b) is a water flow spraying diagram of a nozzle of the present invention.

[0098] Fig.13 It is a schematic diagram of the gas pipeline.

[0099] Fig.14 This is a schematic diagram of the connector of the gas pipeline.

[0100] Fig.15 It is a schematic diagram of a water pipeline.

[0101] Fig.16 is a schematic diagram of a nut.

[0102] Fig.17 It is a schematic diagram showing the connection between the gas pipeline of the body assembly and the gas pipeline of the nozzle assembly.

[0103] Fig.18 It is a cross-sectional view of the sealing cylinder.

[0104] Fig.19 yes Fig.17 Enlarged view of the K part.

[0105] Fig. 20 It is a schematic diagram of the sand cavity.

[0106] Detailed description and specific implementation

[0107] In conjunction with the accompanying drawings, the present invention is described in detail below:

[0108] The dental sandblasting machine processes teeth by jetting abrasive powder mixed with air and water. The dental sandblasting machine comprises a body component and a nozzle component, and the body component and the nozzle component are plug-in connected.

[0109] Nozzle assembly

[0110] In some embodiments, Figure 1 and Figure 2 As shown, a nozzle assembly of a pneumatic dental sandblasting device includes a shell 1, a gas pipeline 2, a water pipeline 3 and a nozzle 4, wherein the gas pipeline 2 and the water pipeline 3 are respectively fixed to the nozzle 4; one end of the shell 1 is connected to the nozzle 4 and the other end is a joint; the shell 1 has a water inlet 301 of the water pipeline 3.

[0111] The joint part seals the nozzle assembly and the machine body assembly to form a workable sandblasting machine. After the nozzle assembly and the machine body assembly are connected, the water pipe outlet 12 (such as Figure 4 ) and the water conduit inlet 301 of the nozzle assembly (as shown Figure 1-Figure 3 As shown in the figure, the nozzle assembly and the body assembly are connected through a sealed cavity or space, so that the water flow is transported from the body assembly to the nozzle assembly and then sprayed out by the nozzle. After the nozzle assembly and the body assembly are sealed and connected, the gas pipeline of the body assembly is sealed and connected with the gas pipeline 2 of the nozzle assembly, and the powder-air mixture is transported from the body assembly to the nozzle assembly and then sprayed out by the nozzle. The nozzle 4 has the jet port inside and the water outlet outside the jet port.

[0112] case

[0113] The shell forms the appearance of the nozzle assembly. In the sandblasting machine, the nozzle is set at one end of the shell and the other end is connected to the machine body assembly. When the sandblasting machine is in use, the doctor holds the shell. The shell and the nozzle are in direct contact with the human oral cavity. It is required that one person has one machine. Therefore, the shell and the nozzle need to be sterilized after each use.

[0114] In some embodiments, Figure 2 As shown, the shell 1 and the nozzle 4 are detachably matched, the shell 1 has a baffle, the gas pipeline 2 passes through the baffle and is locked, and the combination of the gas pipeline 2 and the shell 1 locks the nozzle 4 and the shell 1.

[0115] In some embodiments, Figure 3 and Figure 5 As shown, the housing 1 includes an outer shell 101 and an inner frame 102, and the inner frame 102 is inside the outer shell 101; the joint is provided at one end of the inner frame 102, and the gas pipeline 2 passes through the other end of the inner frame 102 and is locked, and the combination of the gas pipeline 2 and the inner frame 102 locks the nozzle 4, the outer shell 101 and the inner frame 102. The gas pipeline of the nozzle assembly passes through the connecting end of the inner frame to communicate with the gas pipeline of the body assembly. The outer shell 101, the inner frame 102 and the nozzle 4 are three independent components, and when the gas pipeline and the inner frame are locked, the inner frame 102, the outer shell 101 and the nozzle 4 are combined together.

[0116] In some embodiments, a locking piece is provided at the through hole, and the locking piece is tightly matched with the gas pipeline; or the through hole and the gas pipeline are interference-fitted. For example, the locking piece and the gas pipeline are locked by a bevel, keyed, etc. Or, Figure 2 and Fig.16As shown, the nozzle assembly has a locking member 7, the locking member 7 abuts against the baffle 1022 of the inner frame, the locking member 7 is fastened to the gas pipeline through a threaded pair, or the locking member 7 is tightly matched with the gas pipeline; the gas pipeline has a connection end that exposes the locking member 7. This locking member 7 is a part independent of the inner frame. During assembly, the gas pipeline is passed through the baffle of the inner frame and connected to the gas pipeline with the locking member 7. When the locking member 7 abuts against the inner frame, it means that the locking member 7 is connected to the gas pipeline in place. The locking member 7 is a nut, and a threaded section is provided on the gas pipeline. The nut meshes with the threaded section.

[0117] The shell and nozzle assembly method of locking the shell and the gas pipeline is used so that the shell, the inner frame and the nozzle can be made of different materials. For example: the nozzle is made by MIM metal injection molding, and the shell and the inner frame are made of PEAK and / or PPSU high temperature sterilization resistant materials. The nozzle assembly needs to be disinfected and sterilized after each use. The shell and the inner frame made of PAEK and PPSU high temperature sterilization resistant materials may be damaged or cracked after heating 200-500 times, while the MIM injection molded nozzle will basically not be damaged under high temperature disinfection. Therefore, using the locking assembly method, when the shell and / or the inner frame are damaged, only the damaged parts need to be replaced, and the nozzle can still continue to be used, reducing the cost of use.

[0118] The interference fit with the gas pipeline saves manufacturing costs and is easy to install, but during the high-temperature sterilization process, it will cause stress changes in the shell and cause cracks. The nut fastening method uses a nut that meshes with the threaded section through a thread pair, without internal stress, which can reduce the cracking of the shell and extend the service life of the nozzle assembly.

[0119] Inner frame

[0120] The inner frame is used to press the outer shell toward the nozzle, cooperate with the gas pipeline to lock the nozzle and the shell, and accommodate the water pipeline.

[0121] In some embodiments, Figure 3 As shown, the inner frame 102 includes a barrel, a joint portion 1021 is provided at the first end of the barrel, and a baffle is provided at the second end 1022. The baffle has a through hole 1024 that allows the gas pipeline 2 to pass through. In some embodiments, as Figure 3 and Figure 5 As shown, the outer surface of the inner frame 102 is provided with a first step 1023, and the inner surface of the outer shell is provided with a second step 1012 matching the first step 1023; the second step 1012 is closer to the nozzle 4 relative to the first step 1023. As the locking member 7 is combined with the gas pipeline, the first step 1023 presses against the second step 1012 to move the outer shell toward the nozzle 4. Both the first step 1023 and the second step 1012 are annular steps.

[0122] In some embodiments, Fig.17 As shown, the water inlet 301 of the water pipe 3 is arranged on the inner frame 102, and a sealing ring 8 is arranged between the inner frame 102 and the water pipe 3. Fig.15 As shown, the water pipe 3 is bent to avoid the inner frame 102, and a part of the water pipe 3 is located between the inner frame 102 and the outer shell 1. In addition to preventing water from entering the area between the inner frame 102 and the outer shell 1, the sealing ring 8 also plays a positioning role for the water pipe 3 and fixes one end of the water inlet of the water pipe 3. Figure 3 As shown, the barrel of the inner frame 102 has a receiving portion 1025 for receiving the water pipe. The receiving portion 1025 is a notch opened on the surface of the barrel, or the receiving portion 1025 is a hole opened on the barrel. The receiving portion 1025 is connected to the water inlet. The receiving portion 1025 has a limiting effect on the water pipe, and finally the water inlet end of the water pipe is fixed by the sealing ring 8. Fig.17 As shown, a sealing ring 8 is provided at the water inlet end of the water pipe.

[0123] shell

[0124] The outer shell forms the exterior of the nozzle assembly and positions the inner frame and the nozzle.

[0125] In some embodiments, Figure 2 As shown, one end of the housing 1 is against the nozzle 4, and a stopper is provided between the joint surfaces of the housing 1 and the nozzle 4 to prevent the housing 1 and the nozzle 4 from rotating relative to each other. Therefore, after the housing 1 and the nozzle 4 are combined, there is no rotation displacement between the housing 1 and the nozzle 4, and the stability of the nozzle assembly is maintained. Figure 5 (d) and Figure 6 As shown, a protrusion 1013 is provided on the housing 101 , and a groove 4032 matching the protrusion 1013 is provided on the nozzle 4 . The protrusion 1013 is in the groove 4032 , limiting the rotational freedom between the housing 101 and the nozzle 4 .

[0126] In some embodiments, Figure 5 As shown, a positioning rib 1011 is provided in the outer shell 101, and the positioning rib 1011 contacts the inner frame 102, and there is a distance between the positioning rib 1011 and the first step 1012. When the inner frame 102, the outer shell 101 and the nozzle 4 are combined, the positioning rib 1011 and the inner frame 102 are pressed against each other to prevent the inner frame 102, the gas pipeline 2 and the water pipeline 3 from shaking. There are multiple positioning ribs 1011, and the multiple positioning ribs 1011 are evenly arranged around the inner frame. The barrel of the inner frame 102 is cylindrical, and the surface where the positioning rib 1011 contacts the barrel is arc-shaped. Thereby increasing the contact area between the inner frame 102 and the positioning rib 1011, and improving the stability of the positioning of the inner frame 102.

[0127] nozzle

[0128] The water and air mixture is sprayed out from the nozzle, the nozzle is connected to the water pipeline and the gas pipeline respectively, and the nozzle is fixed to the shell.

[0129] In some embodiments, Figure 8 and Fig.10 As shown, the nozzle has a water spray channel A and an air jet channel B, the air jet channel B is inside, and the water spray channel A is outside the air jet channel B; the water spray channel A is formed by the water inlet part 4022 and the water guide part 4023, there are multiple water guide parts 4023, and the outlet of each water guide part 4023 serves as the outlet of a water spray channel A.

[0130] like Figure 7 , Figure 8 and Fig.10 As shown, the nozzle 4 includes a body 401 and a nozzle tube 402, the nozzle is connected to the water pipeline 3 and the gas pipeline 2 respectively, the nozzle 4 has a water spray channel A and an air jet channel B, the air jet channel B is inside, and the water spray channel A is outside the air jet channel B; the body 401 is tightly matched with the nozzle tube 402, the nozzle tube has a water spray channel A, and a water inlet part 4022 and a water guide part 4023 are provided between the nozzle tube 402 and the body 401, and the water inlet part 4022 is connected with the water guide part 4023 to form the water spray channel A.

[0131] There are multiple water guides 4023, and the outlets of the multiple water guides 4023 are evenly distributed around the jet channel B. The nozzle tube 4 is in contact with the body except for the water jet channel A, and water can only be sprayed outward from the water jet channel A, achieving fixed-point and uniform water discharge, increasing the force of water jetting outward, focusing the spray range of water flow and sand particles, and improving the efficiency of cleaning teeth. With improved cleaning efficiency, the sandblasting time will naturally be shortened, and the loss of sand powder will be reduced.

[0132] like Figure 7 As shown, the nozzle body 401 has a water pipe connection channel 4012 and an air pipe connection channel 4011. The water pipe connection channel 4012 is fixed to the water pipe 3, and the air pipe connection channel 4011 is fixed to the gas pipe 2. The nozzle body 401 has a nozzle pipe mounting hole 4013, and the nozzle pipe 402 is inserted into the nozzle pipe mounting hole 4013. The nozzle pipe 402 and the body 401 are tightly matched. Figure 6 As shown, the nozzle has an extension section 403 connected to the housing, and a positioning step 4031 is formed between the extension section 403 and the body 401. The positioning step 4031 can appear as long as there is a size change between the body 401 and the extension section 401. When the housing 101 abuts against the positioning step 4031, it means that the housing 101 and the nozzle 4 are combined in place.

[0133] like Figure 5 (d) and Figure 6As shown, the stopper is arranged between the extension section and the shell, the extension section is inserted into the shell, the stopper is a protrusion 1013 and a groove 4032 that match each other, the protrusion 4031 is located in the extension section, the groove is located in the shell, or the protrusion is located in the shell, and the groove is located in the extension section. When the protrusion is inserted into the groove, the rotational freedom of the nozzle and the shell is unified. The protrusion is a rectangular block, and the groove is a rectangular groove. There are multiple stoppers, and the multiple stoppers are evenly distributed between the shell and the extension section.

[0134] In some embodiments, Figure 7 As shown, the nozzle body is molded by MIM injection molding, and during the injection molding, a water pipe connecting channel 4012, an air pipe connecting channel 4011 and a steel pipe accommodating cavity 4013 are formed. After the MIM injection molding of the body is completed, the water pipe is connected to the water pipe connecting channel by laser welding, the gas pipe is connected to the air pipe connecting channel by laser welding, and the nozzle pipe 402 is pressed into the steel pipe accommodating cavity 4013, and the nozzle pipe 402 and the body are interference fit.

[0135] In other embodiments, Figure 8 As shown, the nozzle has a connector 10, which has an air pipe interface 1001, a water pipe interface 1002 and a nozzle pipe interface 1003. The air pipe interface and the water pipe interface are respectively connected to the nozzle pipe interface, and the connection part between the air pipe interface and the nozzle pipe interface is staggered with the connection part between the water pipe interface and the nozzle pipe interface.

[0136] When manufacturing the nozzle, the nozzle tube 402 is fixed in the nozzle tube interface 1003, the air inlet is connected to the air pipe interface and the jet channel B, and the water inlet 4022 is connected to the water pipe interface and the water spray channel A. After the connector 10 is connected to the water pipe, the gas pipe, and the nozzle tube, the nozzle body is injection molded, and the nozzle tube is fitted with the body except for the water spray channel A. Water can only be sprayed out from the water spray channel A, achieving fixed-point and uniform water discharge and increasing the force of water spraying outward.

[0137] In other embodiments, Fig.10 As shown, the gas pipeline, water pipeline and nozzle pipe are fixed to the body of the nozzle, the gas pipeline is provided with a mounting hole, the nozzle pipe is inserted into the mounting hole, and the gas pipeline is connected with the jet channel B; the water pipeline is provided with a water spray outlet that runs through the water pipeline, the nozzle pipe passes through the water spray outlet and the water spray outlet is aligned with the water inlet 4022.

[0138] When making the nozzle, the nozzle tube is passed through the water outlet of the water pipe and then inserted into the mounting hole of the gas pipe, and then the nozzle is injection molded. The nozzle tube is fitted with the body except for the water inlet channel A, and water can only be sprayed outward from the water outlet channel A, thereby achieving fixed-point and uniform water discharge and increasing the force of the water spraying outward.

[0139] Nozzle pipe

[0140] The mixture of powder and air is sprayed out from the inner cavity of the nozzle tube, and the water flow is sprayed out from between the nozzle tube and the nozzle.

[0141] In some embodiments, Fig.10 As shown, the nozzle tube 402 is in the shape of a hollow cylinder with a constant outer diameter, and is provided with an air inlet 4021, a water inlet portion 4022 and a water guide portion 4023. The air inlet 4021 is communicated with the inner cavity of the nozzle tube 402, the water inlet portion 4022 and the water guide portion 4023 are isolated from the inner cavity of the nozzle tube 402, and the water inlet portion 4022 is located between the water pipe and the water guide portion 4023; the inner cavity outlet of the nozzle tube 402 serves as the jet outlet of the nozzle 4, and the outlet of the water guide portion 4023 serves as the water spray outlet of the nozzle.

[0142] In some embodiments, Fig.10 As shown in (a), the cross-sectional shape of the water guide portion is rectangular, semicircular, arc-shaped, V-shaped, U-shaped, L-shaped, trapezoidal, etc.

[0143] like Fig.10 As shown in (b), the end of the water diversion section is provided with an extension section 4024, which is cylindrical and smaller than the tube body. Therefore, there is a circular gap between the extension section and the nozzle, and the water flows out through the fixed point of the water diversion part and converges into a ring at the extension section. When the nozzle is in use, the water flows from all the diversion grooves converge into a beam and then are ejected. The length of the extension section does not consume the force of the water flow ejection, and can make the water flow converge into a beam and eject.

[0144] The pipe body of the nozzle pipe is interference-fitted with the steel pipe connecting channel of the connecting piece, the air pipe connecting section and the water inlet portion are located in the connecting piece, and a part of the water guide section is exposed outside the connecting piece.

[0145] like Fig.10 As shown in (c), the water guide section is prismatic, the side of the water guide section serves as the water guide part, and the water guide section is inscribed with the outer circle of the nozzle tube. The water guide section is a right prism; the edges of the water guide section are rounded. When the nozzle tube is embedded in the nozzle body, a channel is formed between the water guide part and the body to allow water to flow through. The prismatic water guide section is easy to process, and the water output of the single-point water line is large, and the cleaning efficiency is high.

[0146] Gas pipeline

[0147] The gas pipeline of the nozzle assembly is connected to the gas pipeline of the body assembly to form a conveying line for conveying the powder-air mixture. In some embodiments, one end of the gas pipeline 2 is fixed to the nozzle, and the other end is a connecting section for connecting to the body assembly. The gas pipeline has a locking portion that is fastened to the shell, and the locking portion is adjacent to the connecting section. The locking portion is an external thread. A nut is built into the shell, and the nut meshes with the locking portion to achieve the purpose of locking the gas pipeline and the shell. The locking portion can be integrated with the gas pipeline.

[0148] In some embodiments, Fig.13 As shown, the gas pipeline 2 includes a pipe body 201 and a connector 202, the connector 202 is fixed to the pipe body 201, and a locking portion 2021 and a connecting section 2022 are provided on the connector 202. The connector 202 and the pipe body 201 are combined into the gas pipeline 2, and the pipe body can still use the existing gas pipeline, and only the locking portion (such as tapping an external thread) needs to be processed on the connector 202 to reduce the manufacturing cost.

[0149] like Fig.14 As shown, the locking portion 2021 of the connector 202 is enlarged relative to the connecting section 2022. In this way, a limiting step can be formed between the connecting section 2022 and the locking section 2021. The limiting step is an inclined surface 2023. When the connecting section is matched with the body assembly, the limiting step 2023 is locked through the inclined surface.

[0150] Circlip

[0151] When the nozzle assembly and the machine body assembly are combined, there is a C-shaped clamping spring 9 between the nozzle assembly and the machine body assembly, and the clamping connection between the nozzle assembly and the machine body assembly is achieved by utilizing the deformation of the clamping spring 9.

[0152] In some embodiments, a C-shaped retaining spring 9 is provided between the nozzle assembly and the body assembly, and the two ends of the retaining spring 9 are blunted. If the ends are spherical, curved, chamfered, etc., they are all blunted ends.

[0153] The clamping spring 9 is installed on the joint part of the inner frame. The machine body assembly is provided with a clamping spring groove matched with the clamping spring 9.

[0154] like Fig.11 As shown, each end of the circlip 9 is a bevel, and the bevel faces the body assembly. The bevel faces the body assembly, and the bevel forms an obtuse angle with the inner ring of the circlip 9. The smaller diameter is used as the inner ring, and the larger diameter is used as the outer ring. The bevel reduces the wear between the circlip 9 and the body assembly.

[0155] The edge of the bevel is a smooth curved surface. When the two ends of the clamp spring 9 are smooth curved surfaces such as ball heads and arc surfaces, there is no cutting between the clamp spring 9 and the body assembly, so when the nozzle assembly and the body assembly are plug-in connected, the clamp spring 9 and the body assembly can be prevented from wearing each other.

[0156] Sealing tube

[0157] The sealing cylinder 5 is a component for connecting and sealing the gas pipeline of the nozzle assembly and the gas pipeline of the body assembly, so as to achieve the purpose of preventing sand from being blocked or leaking during the transportation of the air-powder mixture. The sealing cylinder 5 is made of a flexible material, and the sealing cylinder 5 is sealed and connected to the gas pipeline. For example, the sealing cylinder 5 is a silicone cylinder, and the sealing cylinder 5 is sealed and connected to the gas pipeline 2. There is a connecting shell outside the sealing cylinder 5. The connecting shell supports the sealing cylinder and prevents the sealing cylinder from being deformed due to the plugging of the body assembly and the gas pipeline, causing sand leakage or blockage.

[0158] In some embodiments, Fig.18 As shown, the sealing tube 5 includes a plug-in end connection part 501 and a fixed end connection part 502 located at both ends, and a transition cavity 503, wherein the transition cavity 503 is located between the plug-in end connection part 501 and the fixed end connection part 502, the plug-in end connection part 501 is connected to the connecting section of the gas pipeline of the nozzle assembly, and the fixed end connection part 502 is used to be connected to the gas pipeline of the body assembly.

[0159] The sealing tube 5 is a tube body made of wear-resistant elastic materials such as a silicone tube, a latex tube or a rubber tube.

[0160] That is to say, the gas pipeline of the body assembly is not in direct contact with the gas pipeline of the nozzle assembly, but is in contact with the sealing cylinder respectively. The sealing cylinder is made of flexible material, has good wear resistance and good elastic deformation and deformation recovery capabilities, and delays the occurrence of sand leakage and sand blockage.

[0161] A sealing cylinder is arranged between the gas pipeline of the machine body component and the gas pipeline of the nozzle component, and the sealing cylinder is respectively connected with the two gas pipelines in a sealed manner, so that the two gas pipelines are not in direct contact and there is no wear between the gas pipelines; the gas pipeline is a rigid part and the sealing cylinder is a flexible part, the sealing cylinder has good wear resistance and is not easy to deform, thereby increasing the number of plug-in times of the nozzle component and the machine body component and extending the service life of the sandblasting machine.

[0162] Before the sandblasting machine is used, the nozzle assembly and the body assembly are plugged and sealed. When the water flows from the body assembly into the nozzle assembly, it flows into the water pipe of the nozzle assembly through the gap between the body assembly and the nozzle assembly. In the sandblasting machine in the prior art, the gas pipe of the body assembly and the gas pipe of the nozzle assembly are connected in a way that two metal gas pipes are in contact, and a sealing ring is set between the two gas pipes for sealing. However, during the long-term sandblasting process, the sand powder will cause the metal pipe wall to be damaged during the sandblasting process, and the water vapor will enter the connection part of the two gas pipes from the body assembly and the nozzle assembly, causing the sand powder to agglomerate in the gas pipe and cause the gas pipe to be blocked. In this article, the two ends of the sealing cylinder are respectively connected to the two gas pipes, and the two gas pipes are not in contact with each other. When the sand powder passes through the connection part of the two gas pipes, it collides with the sealing cylinder, which is equivalent to converting the impact on the metal gas pipe into the impact on the sealing cylinder. The sealing cylinder is used to realize the transition of the sand particles from the body assembly to the nozzle assembly. The sealing cylinder is elastic. During the sandblasting process, the sand powder will be rebounded when it hits the sealing cylinder wall without wearing the sealing cylinder. The problem of metal pipe damage is solved, so the life of the nozzle assembly is increased. The sealing tube not only seals and isolates water vapor, but also buffers the impact of sand powder on the gas pipeline, allowing the sand powder to smoothly transition from the body assembly to the nozzle assembly.

[0163] Concentric steps

[0164] During the use of the sandblasting machine, the nozzle assembly and the machine body assembly need to be able to rotate freely relative to each other. Therefore, the joint of the nozzle assembly and the joint of the machine body assembly must meet the concentricity requirements after assembly to ensure the smoothness of rotation.

[0165] In some embodiments, the body assembly of the pneumatic dental sandblaster has a step C, and the nozzle assembly has a mating surface D that matches the step C; the step C or the surface of the step C is a plastic part.

[0166] There are two steps C that are in contact with the corresponding mating surface D at the same time, and the two steps C are concentric; each step C corresponds to a mating surface D. The two concentric steps C support the cooperation between the nozzle assembly and the body assembly, and the nozzle assembly and / or the body assembly rotate around the axis with the center line of the two steps C as the axis. This ensures that during the working process, the sand cavity of the body assembly is always facing upward, and the air-powder mixture can be smoothly transported.

[0167] A sealing ring for sealing water flow is provided on the body assembly, and the sealing ring is located between two concentric steps C. Step C is a conical step C, and the matching surface D is a slope.

[0168] In some embodiments, the mating surface D of the nozzle assembly is provided at the joint portion of the nozzle assembly, the step C of the body assembly is provided at the joint portion of the body assembly, the joint portion of the nozzle assembly is a plastic part, and the joint portion of the body assembly is an integrally formed metal part. The joint portion of the aforementioned nozzle assembly is located in the inner frame, the inner frame is independent of the outer shell, the inner frame can be a plastic part, and therefore the joint portion is a plastic part. At this time, the joint portion of the body assembly only needs to be integrally formed with two concentric steps C. By integrally forming two concentric steps C, the direct concentricity of the two steps C is reliable and easy to process.

[0169] Alternatively, in some embodiments, the mating surface D of the nozzle assembly is a metal part, and the step C of the body assembly is a plastic part. Preferably, the body assembly includes a metal joint body and a plastic collar, each plastic collar forms a step C, and the plastic collar is fixed to the joint body. The plastic collar is fixed to the joint body by interference fit, bonding, thermoplasticization or injection molding.

[0170] When the joint of the nozzle assembly and the joint of the body assembly are both metal parts, in order to avoid severe wear caused by direct contact between the metal surfaces, two plastic collars are set at the joint of the body assembly. The plastic collars are in contact with the joint of the nozzle assembly, and there is a gap between the joint of the body assembly except for the plastic collars and the joint of the nozzle assembly. In this way, the direct wear of the two metal surfaces and the increase in concentricity are avoided.

[0171] sand cavity

[0172] The sand chamber is a chamber in the sandblasting machine for storing sand powder. The pressurized air delivery pipe and the gas pipeline of the machine body assembly are inserted into the sand chamber. After the pressurized air enters the sand chamber, the sand powder is dispersed to form an air-powder mixture. The air-powder mixture enters the gas pipeline, and the sand powder is transported.

[0173] In some embodiments, Fig. 20 As shown, a maximum powder adding amount marking line 131 is provided in the sand chamber 13 of the sandblasting machine. The maximum powder adding amount marking line can indicate the maximum amount of powder added by the doctor. There are a pressurized air delivery pipe 14 and a gas pipeline 15 of the machine body assembly in the sand chamber. The pressurized air delivery pipe 14 has an air outlet, and the gas pipeline 15 of the machine body assembly has an air powder inlet; the marking line 131 is lower than the air outlet and the air powder inlet. Avoid the powder (sand powder) from entering the pressurized air delivery pipe 14 and the gas pipeline due to the customer adding too much powder, resulting in sand blockage. The inner surface of the sand chamber is spherical.

[0174] The body assembly of the sandblasting machine is provided with a mounting portion 16 of the sand cavity 13, the sand cavity 13 is embedded in and fixed to the mounting portion 16, and the sand cavity 13 has a top edge 132 that is higher than the mounting portion 16; the sandblasting machine has a sand cavity 13 cover, the mounting portion 16 has a connecting portion that matches the sand cavity 13 cover, and the sand cavity 13 cover has a sealing ring. After the sand cavity 13 cover and the mounting portion 16 are connected in place, the sealing ring is pressed between the sand cavity 13 cover and the top edge 132. The top edge 132 of the sand cavity 13 is higher than the mounting portion 16, so as to prevent the powder in the sand cavity 13 from falling into the gap at the connection between the sand cavity 13 and the mounting portion 16.

[0175] The air outlet of the pressurized air delivery pipe 14 and the air powder inlet of the gas pipe are lower than the top edge of the sand cavity 13. The air outlet and the air powder inlet are located inside the sand cavity 13, which is conducive to the pressurized air dispersing all the powder (or sand powder) in the sand cavity 13, so that the powder filled each time can be used up, thereby improving the exhaustion rate of the pre-loaded powder in the sand cavity 13.

[0176] The sand cavity 13 has an outer ring edge extending outward, and the mounting portion 16 is within the area covered by the outer ring edge. In this way, the sand cavity 13 completely covers the connection between the sand cavity 13 and the mounting portion 16, and when adding powder, the powder will not fall into the connection area between the sand cavity 13 and the mounting portion 16.

[0177] The mounting portion 16 and the sand chamber 13 cover are connected by a threaded pair. The sand chamber 13 cover has a transparent window. The marking line is within the visible range of the window.

[0178] Removable nozzle assembly

[0179] In some embodiments, the nozzle assembly includes a housing 1, a nozzle 4 and a gas pipeline 2, and the nozzle 4 is fixed to the gas pipeline 2; the housing 1 and the nozzle 4 are detachably matched, the gas pipeline 3 has a threaded section, the housing 1 has a baffle, the threaded section passes through the baffle and engages with the nut 7, and the gas pipeline 2 and the nut 7 lock the housing 1 and the nozzle 4. The threaded section 202 is provided on the connector, and the connector is fixedly connected to the gas pipeline 2. The connector is fixed to the end of the gas pipeline 2, and the connector has a connecting section that is connected to the body assembly.

[0180] When the nut 7 is locked in place with the threaded section 202, the nut 7 abuts against the baffle 1022. The inner diameter of the through hole is larger than the outer diameter of the threaded section 202, and the through hole is smaller than the nut 7. The end of the nut 7 abutting against the baffle 1022 is the first end, and there is a force-applying portion on the second end of the nut 7. The force-applying portion is a slot, or the force-applying portion is a stop plane. For example, if the nut 7 is a hexagonal nut 7, each side of the nut 7 is a stop plane. For another example, the outer surface of the nut 7 has a plane, and a sleeve that matches the shape of the nut 7 is used, and the sleeve abuts against the plane of the nut 7 to make the nut 7 rotate with the sleeve, then the plane on the outer surface of the nut 7 is the stop plane. During assembly, first insert the inner frame 102 into the outer shell 101, and align the gas pipeline 2 with the through hole; push the step C of the inner frame 102 toward the step C of the outer shell 101, and let the threaded section 202 of the gas pipeline 2 pass through the through hole; rotate the nut 7 along the threaded section 202 until the step C of the inner frame 102 and the step C of the outer shell 101 are pressed against each other. When the outer shell 101 and the inner frame 102 need to be disassembled, the nut 7 is loosened and removed, and the outer shell 101 and the inner frame 102 can be separated. This nozzle 4 assembly is easy to disassemble, and is easy to repair and replace parts.

[0181] Anti-clogging sandblasting machine

[0182] In some embodiments, the anti-clogging sandblasting machine includes a body assembly and a nozzle assembly connected in a plug-in manner, the nozzle assembly and the body assembly respectively have their own gas pipelines, and the gas pipeline of the nozzle assembly and the gas pipeline of the body assembly are connected through a sealing tube.

[0183] like Fig.17 As shown, the gas pipeline 2 of the nozzle assembly is sealed and connected to the sealing cylinder 6, and the gas pipeline 7 of the body assembly is also connected to the sealing cylinder. The sealing cylinder serves as an intermediate cavity to connect the two gas pipelines. The sealing cylinder is a tube-shaped tube with two openings at both ends, and the two ends of the sealing cylinder are respectively provided with connection parts that seal with the two gas pipelines.

[0184] In some embodiments, there is a transition chamber 503 between the gas pipeline of the nozzle assembly and the gas pipeline of the body assembly, and the transition chamber 503 is the inner chamber of the sealing cylinder. The outlet of the transition chamber 503 is connected with the gas pipeline of the nozzle assembly, and the inlet of the transition chamber 503 is connected with the gas pipeline of the body assembly. The so-called connection means that when the airflow enters the transition chamber 503 from the gas pipeline of the body assembly, the transition chamber 503 does not block the airflow, and when the airflow enters the gas pipeline of the nozzle assembly from the transition chamber 503, the gas pipeline of the nozzle assembly does not block the airflow.

[0185] In some embodiments, Fig.18 As shown, both ends of the sealing cylinder are provided with connection parts which are sealed with two gas pipelines, one of which is a fixed end connection part 502, and the other is a plug-in end connection part 501. The fixed end connection part 502 has a groove, and the gas pipeline connected to the fixed end connection part 502 is provided with a protrusion which can be embedded in the groove; the plug-in end connection part 501 is a cavity which is tightly matched with another gas pipeline.

[0186] The outer end of the plug-end connection portion 501 is provided with a guiding slope.

[0187] In some embodiments, the sealing cylinder is a rubber cylinder or a silicone cylinder.

[0188] The fixed end connection part 502 is connected to the gas pipeline of the body assembly, and the body assembly has a protective shell that wraps the sealing cylinder therein; the plug-in end connection part 501 is connected to the gas pipeline of the nozzle assembly. The protective shell and the gas pipeline sandwich the sealing cylinder between them, so that the sealing cylinder has both flexibility to achieve a sealed connection when plugged into the gas pipeline of the nozzle assembly, and rigidity to avoid connection failure caused by deformation of the sealing cylinder.

[0189] A guiding slope is provided on the plug-in end connection part 501. The guiding slope matches the above-mentioned limiting step C. When the gas pipeline is inserted into place, the limiting step C is close to the guiding slope. The contact area of ​​the two slopes is increased, and the reliability of the seal is improved.

[0190] The preferred solution is to set the sealing cylinder on the machine body assembly. Because the nozzle assembly requires one person per machine when in use, that is, after each customer who uses the sandblasting and teeth cleaning machine has finished using it, the nozzle assembly needs to be disinfected. By setting the sealing cylinder on the machine body assembly, the sealing cylinder will not limit the applicable disinfection method of the nozzle assembly. In addition, the sealing cylinder is not disinfected by high temperature, high pressure, ultraviolet light, etc., which can extend the service life of the sealing cylinder and ensure that the sandblasting machine does not leak sand or get blocked during long-term use.

[0191] Of course, arranging the sealing cylinder on the nozzle assembly is also an optional solution, and only the sterilization method suitable for the sealing cylinder needs to be selected. In some embodiments, the fixed end connection part 502 is connected to the gas pipeline of the nozzle assembly, and the plug end connection part 501 is connected to the gas pipeline of the body assembly.

[0192] Pneumatic dental sandblaster

[0193] During the use of the sandblasting machine, the nozzle assembly and the machine body assembly need to be able to rotate freely relative to each other. Therefore, the joint of the nozzle assembly and the joint of the machine body assembly must meet the concentricity requirements after assembly to ensure the smoothness of rotation.

[0194] like Fig.16 and Fig.19 As shown, the pneumatic dental sandblaster comprises a nozzle assembly and a body assembly, wherein the body assembly has a step C, and the nozzle assembly has a matching surface D matching with the step C; the step C or the surface of the step C is a plastic part.

[0195] There are two steps C that are in contact with the corresponding mating surface D at the same time, and the two steps C are concentric; each step C corresponds to a mating surface D. The two concentric steps C support the cooperation between the nozzle assembly and the body assembly, and the nozzle assembly and / or the body assembly rotate around the axis with the center line of the two steps C as the axis. This ensures that during the working process, the sand cavity 13 of the body assembly is always facing upward, and the air-powder mixture can be smoothly conveyed.

[0196] A sealing ring for sealing water flow is provided on the body assembly, and the sealing ring is located between two concentric steps C. Step C is a conical step C, and the matching surface D is a slope.

[0197] In some embodiments, the mating surface D of the nozzle assembly is provided at the joint portion of the nozzle assembly, the step C of the body assembly is provided at the joint portion of the body assembly, the joint portion of the nozzle assembly is a plastic part, and the joint portion of the body assembly is an integrally formed metal part. The joint portion of the aforementioned nozzle assembly is located in the inner frame, the inner frame is independent of the outer shell, the inner frame can be a plastic part, and therefore the joint portion is a plastic part. At this time, the joint portion of the body assembly only needs to be integrally formed with two concentric steps C. By integrally forming two concentric steps C, the direct concentricity of the two steps C is reliable and easy to process.

[0198] Alternatively, in some embodiments, the mating surface D of the nozzle assembly is a metal part, and the step C of the body assembly is a plastic part. Preferably, the body assembly includes a metal joint body and a plastic collar, each plastic collar forms a step C, and the plastic collar is fixed to the joint body. The plastic collar is fixed to the joint body by interference fit, bonding, thermoplasticization or injection molding.

[0199] When the joint part of the nozzle assembly and the joint part of the body assembly are both metal parts, in order to avoid severe wear due to direct contact of the metal surfaces, two plastic collars are set at the joint part of the body assembly, and the plastic collars are in contact with the joint part of the nozzle assembly. The area of ​​the joint part of the body assembly other than the plastic collar has a gap with the joint part of the nozzle assembly. In this way, the two metal surfaces are prevented from directly wearing each other and causing increased concentricity. The invention shown and described herein can be implemented in the absence of any element or restriction specifically disclosed herein. The terms and expressions used are used as illustrative terms rather than limiting, and it is not intended to exclude any equivalents of the features shown and described or parts thereof in the use of these terms and expressions, and it should be recognized that various modifications are feasible within the scope of the present invention. Therefore, it should be understood that although the present invention is specifically disclosed through various embodiments and optional features, modifications and variations of the concepts described herein can be adopted by ordinary technicians in the field, and it is considered that these modifications and variations fall within the scope of the present invention defined by the attached claims.

[0200] The contents of the articles, patents, patent applications, and all other documents and electronically available information described or recorded herein are incorporated by reference in their entirety to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. Applicants reserve the right to incorporate into this application any and all materials and information from any such article, patent, patent application, or other document.

Claims

1. A nozzle assembly of a pneumatic dental sandblasting device, comprising a housing, a gas pipeline, a water pipeline and a nozzle, wherein the gas pipeline and the water pipeline are respectively fixed to the nozzle; one end of the housing is connected to the nozzle, and the other end is a joint; the joint seals the nozzle assembly and the body assembly to form a working sandblasting machine; the housing has a water inlet of the water pipeline; and the characteristics are: The shell includes an outer shell and an inner frame, the inner frame is inside the outer shell, the water inlet of the water pipe is arranged on the inner frame, and a sealing ring is arranged between the inner frame and the water pipe; a first step is arranged on the outer surface of the inner frame, and a second step matching the first step is arranged on the inner surface of the outer shell; the second step is closer to the nozzle relative to the first step; a positioning rib is arranged in the outer shell, the positioning rib is in contact with the inner frame, and there is a distance between the positioning rib and the first step. When the inner frame, the outer shell and the nozzle are combined, the positioning rib and the inner frame are pressed against each other to prevent the inner frame, the gas pipe and the water pipe from shaking; one end of the outer shell is against the nozzle, and a limiter is arranged between the joint surfaces of the outer shell and the nozzle to prevent the outer shell and the nozzle from rotating relative to each other. The limiter is a protrusion and a groove matching each other to maintain the stability of the nozzle assembly; the nozzle has a water spray channel A and an air jet channel B, and the water spray channel A is formed by connecting the water inlet part and the water guide part There are multiple water guides, the outlet of each water guide serves as the outlet of a water spray channel A, and the outlets of the multiple water guides are evenly distributed around the jet channel B. The water inlet divides the pipe body into an air pipe connecting section and a water guide section; the water guide is located in the water guide section, the water guide section is prismatic, and an extension section is provided at the end of the water guide section; a sealing cylinder is provided between the gas pipeline of the nozzle assembly and the gas pipeline of the body assembly, the gas pipeline of the nozzle assembly is sealed and connected to the sealing cylinder, and the gas pipeline of the body assembly is also connected to the sealing cylinder, and the two ends of the sealing cylinder are respectively provided with connecting parts that seal with the two gas pipelines, the gas pipeline is a rigid part, the sealing cylinder is a flexible part, and the sealing cylinder is elastic; the joint part is provided at one end of the inner frame, the gas pipeline passes through the other end of the inner frame and is locked, and the combination of the gas pipeline and the inner frame locks the nozzle, the outer shell and the inner frame.

2. The nozzle assembly of the pneumatic dental sandblasting device according to claim 1, characterized in that: The inner frame is provided with a locking piece, which is tightly matched with the gas pipeline.

3. The nozzle assembly of the pneumatic dental sandblasting device according to claim 1, characterized in that: The nozzle assembly has a locking piece, which abuts against the end plate of the inner frame. The locking piece is fastened to the gas pipeline through a threaded pair or the locking piece is tightly matched with the gas pipeline; the gas pipeline has a connection end that exposes the locking piece.

4. The nozzle assembly of the pneumatic dental sandblasting device according to claim 2 or 3, characterized in that: The locking piece is a nut, and a threaded section is provided on the gas pipeline.

5. The nozzle assembly of the pneumatic dental sandblasting device according to claim 4, characterized in that: There are a plurality of positioning ribs, and the plurality of positioning ribs are evenly arranged around the inner frame.

6. The nozzle assembly of the pneumatic dental sandblasting device according to claim 5, characterized in that: The barrel of the inner frame is cylindrical, and the contact surface between the positioning rib and the inner frame is arc-shaped.

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