Spray head assembly and in-hole molded surface coating spraying process
By designing the gas channel and paint channel of the nozzle assembly and combining it with the concave area of the spherical cap, uniform spraying of fine and deep hole inner surfaces is achieved, solving the problem of uneven spraying in the existing technology, reducing costs and improving spraying efficiency.
Patent Information
- Application Number
- CN202511018937.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-23
- Publication Date
- 2025-09-30
AI Technical Summary
The existing spraying process makes it difficult to achieve uniform coating formation on the surface inside fine and deep holes, the brushing process cannot guarantee flatness, the dipping process is costly and requires special tooling, and the spraying process is limited by the size of the nozzle.
A nozzle assembly is designed, including a gas channel and a paint channel in a cylindrical main body, with an air jet port and a material spray port. Combined with the concave area of the spherical cap, the paint is atomized and sprayed evenly through high-speed and high-pressure gas, which is suitable for spraying on the surface inside the hole.
It achieves uniform spraying of the inner surface of the hole, reduces costs and improves spraying efficiency. It is suitable for coating molding on the inner wall of deep holes with a hole diameter of 10mm-100mm.
Smart Images
Figure CN120714831A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of spraying devices and thermal protective coatings, and more particularly to a simple and detachable spray head assembly and an in-hole profile coating spraying process. Background Art
[0002] For spraying protective coatings on the surfaces of mechanical parts, spraying, brushing, and dipping are commonly used. Brushing, which is often done manually, is suitable for parts with complex, shallow surfaces; dipping is suitable for individual components with integrated insulation between the inner and outer surfaces; and spraying can be applied to large-area, complex surfaces. Existing processes are not well suited for coating the inner surfaces of thin, deep holes (with an inner diameter of 10mm-100mm). Brushing struggles to ensure surface smoothness, dipping requires specialized tooling, resulting in high costs and long cycles, and spraying is generally limited by nozzle size. Summary of the Invention
[0003] In view of the defects or shortcomings of the prior art, the present invention provides a nozzle assembly.
[0004] To this end, the nozzle assembly provided by the present invention includes a nozzle unit, the main body of the nozzle unit is cylindrical, and a gas channel and three paint channels are provided in the cylindrical main body, and the gas channel and each paint channel are arranged along the axial direction of the cylindrical main body; three air jets are opened on the side wall of the gas channel, and the three air jets are located on the side wall surface of the cylindrical main body; a material injection port is opened on the side wall of each paint channel, and the material injection port is located on the side wall surface of the cylindrical main body; and the three air jets are identical in shape and size, and the three material injection ports are identical in shape and size;
[0005] At the same time, three recessed areas are provided on the side wall surface of the cylindrical body, each recessed area is formed by the indentation of a spherical cap on the side wall surface of the cylindrical body, and the height of the spherical cap is set along the radial direction of the cylindrical body, and the curvature of any arc on the spherical cap passing through the highest point of the spherical cap is 120°; the three recessed areas correspond to the same radius of the spherical surface where the spherical cap is located, the three recessed areas correspond to the same height of the spherical cap, and the three recessed areas are equidistantly spaced along the same circumferential direction; the three jet ports are respectively located at the highest points of the spherical caps corresponding to the three recessed areas, and the three jet ports are equidistantly distributed along the same circumferential direction; the three injection ports are respectively located in the three recessed areas and are located beside the corresponding injection ports, and the three injection ports are equidistantly distributed along the same circumferential direction.
[0006] An optional solution is that the gas channel is arranged along the central axis of the cylindrical body, and the three coating channels are arranged around the gas channel.
[0007] An optional solution is that the size of the injection port is measured based on the area of an equivalent circle, and the radius of the equivalent circle is 0.5 mm to 3 mm.
[0008] An optional solution is to include at least two nozzle units connected in sequence along the axial direction, the gas channels in adjacent nozzle units are connected in sequence along the axial direction, and the coating channels in adjacent nozzle units are connected in sequence along the axial direction.
[0009] An optional solution is that the size of the spray port is measured based on the equivalent circle area, and along the direction of the material, the equivalent circle radius of the spray port on the same axial coating channel increases successively.
[0010] Alternatively, the spray head assembly of the present invention further includes an adapter having a gas inlet and three paint inlets, the adapter being axially connected to the spray head unit, the gas inlet being connected to the gas passage, and the three paint inlets being connected to the three paint passages, respectively. The assembly further includes an extension rod having a gas passage and three paint passages, the adapter being connected to the spray head unit via the extension rod, the gas inlet, the gas passage, and the gas passages being sequentially connected, and the three paint inlets being connected to the three paint passages, respectively, via the three paint passages.
[0011] An optional solution is that the outer diameter of the spray unit body is 8mm-90mm, such as 8mm-10mm, 10mm-20mm, 20mm-30mm, 30mm-40mm, 40mm-50mm, 50mm-60mm, 60mm-70mm, 70mm-80mm, 80mm-90mm, etc.
[0012] The present invention also provides a process for spraying coatings on profiled surfaces within a hole. The diameter of the hole to be sprayed ranges from 10 mm to 100 mm. The process involves inserting the aforementioned nozzle assembly into the hole for spraying. The process uniformly sprays the profiled surface within the hole by selecting a spray orifice of appropriate size and controlling the air inlet pressure within the gas channel and the coating flow rate within the coating channel. Optionally, the spray orifice has an equivalent circular radius of 0.5 mm to 3 mm, the air inlet pressure is 0.1 MPa to 0.8 MPa, and the coating flow rate in each coating channel is 0.5 to 20 g / s.
[0013] The nozzle assembly device of the present invention is easy to disassemble, convenient for cleaning, repair and replacement of parts. The nozzle assembly of the present invention is suitable for forming surface coatings in deep holes with small apertures. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 Schematic diagram of the structure of the nozzle unit of the present invention.
[0015] Figure 2 Schematic diagram of the structure of the nozzle assembly of the present invention. DETAILED DESCRIPTION
[0016] Unless otherwise specified, the scientific and technical terms used herein are understood according to the knowledge of ordinary technicians in the relevant fields.
[0017] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.
[0018] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.
[0019] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.
[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0021] Example:
[0022] The spray assembly of the present invention comprises at least one spray head unit, see Figure 1 As shown, the main body of the nozzle unit is cylindrical, and a gas channel 12 and three paint channels 13 are provided in the cylindrical main body 11 along its axial direction, wherein the gas channel is provided with three air jets, and each paint channel is provided with a material spraying port, wherein the three air jets and the three material spraying ports are all located on the side surface of the cylindrical main body, and the three air jets have the same diameter, the three material spraying ports have the same shape and size, and the three material spraying ports have the same shape and size;
[0023] To ensure uniform spraying, three recessed areas are provided on the side surface of the cylindrical main body (i.e., recessed from the surface to the center), and each recessed area is formed by the indentation of a spherical crown on the side wall surface of the cylindrical main body, and the height of the spherical crown is set along the radial direction of the cylindrical main body, and the curvature of any arc on the spherical crown passing through the highest point of the spherical crown is 120°; the three recessed areas correspond to the same radius of the spherical surface where the spherical crown is located, the three recessed areas correspond to the same height of the spherical crown, and the three recessed areas are equidistantly distributed along the same circumferential direction; the three air jets are respectively located at the highest points of the spherical crowns in the three recessed areas, and the three air jets are equidistantly distributed along the same circumferential direction; the three spray ports are respectively located in the three recessed areas and are located beside the corresponding air jets.
[0024] During use, the paint enters from each paint channel and flows out through the corresponding paint nozzle, and is atomized and sprayed to the target area under the action of high-speed and high-pressure gas ejected from the corresponding air jet outlet on the side; and the three circumferentially distributed concave areas of the spherical cap structure can ensure that the sprayed paint is evenly dispersed in the circumferential target area.
[0025] In the specific scheme, the opening of each channel in the cylindrical body facilitates the passage of materials, cleaning and processing of related structural parts. Figure 1 The cylindrical body shown features a gas channel arranged along its central axis, with three coating channels distributed around the gas channel. Specifically, to facilitate processing, the air jets are formed as through-holes where the corresponding recessed areas intersect or are tangential to the sidewalls of the gas channel, while the material injection ports are formed as through-holes where the corresponding recessed areas intersect or are tangential to the sidewalls of the coating channels.
[0026] In a specific solution, a suitable number of nozzle units can be selected according to the depth of the hole to be sprayed and assembled axially into a nozzle assembly of suitable length. In a specific solution, adjacent nozzle units can be connected by threads. Figure 2 The nozzle assembly includes three nozzle units (1, 2, 3), the gas channels in adjacent nozzle units are connected in sequence along the axial direction, and the paint channels in adjacent nozzle units are connected in sequence along the axial direction; three threaded holes 17 are provided in the main body of each nozzle unit, and the threaded holes in the three nozzle units pass through in the axial direction, and the three nozzle units are assembled together with three bolts. The gas and paint flow through each nozzle unit and are sprayed out through their respective nozzles to spray the target area. In the preferred embodiment, in order to ensure uniform spraying on the circumferential direction of the inner surface of the hole, a metering method of equivalent circle area is adopted, and along the direction of the material, the equivalent circle radius of the spray port on the same axial paint channel increases successively, such as Figure 2 shown.
[0027] In a further embodiment, to facilitate feeding, an adapter 5 is connected to the end of the spray assembly. The adapter is provided with a gas inlet and three paint inlets. The adapter is axially connected to the spray head unit, and the gas inlet is connected to the gas channel. The three paint inlets are respectively connected to the three paint channels, and the gas and paint are fed into their respective channels through the corresponding inlets. To facilitate operation, when spraying the inner surface of a deeper hole, an extension rod 4 is installed between the adapter and the adjacent spray head unit. The extension rod is provided with a gas channel and three paint channels. The adapter is connected to the spray head unit via the extension rod, and the gas inlet, gas channel, and gas channel are connected in sequence. The three paint inlets are respectively connected to the three paint channels through the three paint channels; the gas and paint are fed into the spray head unit through the corresponding channels in the extension rod. Figure 2 The adapter and the extension rod are both provided with three threaded holes. The threaded holes in the adapter, the extension rod and each nozzle unit are circumferentially connected, and three screws 18 are used to axially assemble and connect the components.
[0028] The nozzle assembly of the present invention is particularly suitable for spraying coatings within holes with an inner diameter of 10mm-100mm. Specifically, the nozzle assembly is inserted into the hole. During the process, the inner wall of the tube is evenly sprayed by selecting an appropriate spray orifice size (which can be measured by equivalent circular area in specific embodiments) and controlling the air pressure in the gas channel and the coating flow rate in the coating channel. Optionally, the equivalent circular radius of the spray orifice is 0.5mm-3mm, the air pressure is 0.1-0.8MPa, and the coating flow rate in each coating channel is 0.5-20g / s.
[0029] In the specific solution, under the premise of ensuring uniform spraying, the dimensions of the main body and related structural parts of each nozzle unit can be selected and designed according to the structure in the hole to be sprayed.
[0030] If using Figure 2The spray assembly shown sprays the interior of an elongated, 30mm-inner-diameter, 400mm-long, bore-like tube. The coating is a thermally insulating organic coating. The axial dimensions of the adapter, extension rod, nozzle unit 1, nozzle unit 2, and nozzle unit 3 in the nozzle assembly are 30mm, 300mm, 50mm, 50mm, and 50mm, respectively. The radial dimensions are all 20mm. Each nozzle is circular with a 1.2mm radius. Along the material flow path, the equivalent circle radii of each nozzle are 2mm, 1.6mm, and 1.1mm, respectively. The spherical cap height of each recessed area is 13mm, and the radius of the sphere within it is 50mm. During spraying, the gas channel inlet pressure is 0.6MPa, and the coating flow rate in each coating channel is 3g / s. Five spray passes are performed (each pass lasts 1s). At the same time, the metal plate was sprayed 5 times using the same process (single spraying was 1s), and the thickness of the inorganic coating at multiple points was detected using an ultrasonic thickness meter. The average coating thickness at each point on the plate surface was 1mm, and the error did not exceed 0.02mm, indicating that the nozzle assembly of the present invention achieved uniform spraying of the coating on the inner wall of the hole.
Claims
1. A nozzle assembly, characterized in that: The nozzle unit comprises a cylindrical main body, a gas channel and three paint channels provided in the cylindrical main body, the gas channel and each paint channel being arranged along the axial direction of the cylindrical main body; three air jets are provided on the side wall of the gas channel, and the three air jets are located on the side wall surface of the cylindrical main body; a material spray port is provided on the side wall of each paint channel, and the material spray port is located on the side wall surface of the cylindrical main body; the three air jets are of the same shape and size, and the three material spray ports are of the same shape and size; At the same time, three recessed areas are provided on the side wall surface of the cylindrical body, each recessed area is formed by the indentation of a spherical cap on the side wall surface of the cylindrical body, and the height of the spherical cap is set along the radial direction of the cylindrical body, and the curvature of any arc on the spherical cap passing through the highest point of the spherical cap is 120°; the three recessed areas correspond to the same radius of the spherical surface where the spherical cap is located, the three recessed areas correspond to the same height of the spherical cap, and the three recessed areas are equidistantly spaced along the same circumferential direction; the three jet ports are respectively located at the highest points of the spherical caps corresponding to the three recessed areas, and the three jet ports are equidistantly distributed along the same circumferential direction; the three injection ports are respectively located in the three recessed areas and are located beside the corresponding injection ports, and the three injection ports are equidistantly distributed along the same circumferential direction.
2. The nozzle assembly according to claim 1, wherein: The gas channel is arranged along the central axis of the cylindrical body, and the three coating material channels are arranged around the gas channel.
3. The nozzle assembly according to claim 1, wherein: The size of the injection port is calculated based on the area of an equivalent circle, and the radius of the equivalent circle is 0.5 mm to 3 mm.
4. The nozzle assembly according to claim 1, wherein: It comprises at least two nozzle units connected in sequence along the axial direction, the gas channels in adjacent nozzle units are connected in sequence along the axial direction, and the coating channels in adjacent nozzle units are connected in sequence along the axial direction.
5. The nozzle assembly according to claim 4, characterized in that: The size of the spray port is calculated based on the equivalent circle area. Along the direction of the material, the radius of the equivalent circle of the spray port on the same axial coating channel increases successively.
6. The nozzle assembly according to claim 1, wherein: It also includes an adapter, which is provided with a gas inlet and three paint inlets. The adapter is axially connected to the nozzle unit, and the gas inlet is connected to the gas channel, and the three paint inlets are respectively connected to the three paint channels.
7. The nozzle assembly according to claim 6, wherein: It also includes an extension rod, which is provided with a gas passage and three paint passages. The adapter is connected to the nozzle unit through the extension rod, and the gas inlet, gas passage and gas channel are connected in sequence. The three paint inlets are connected to the three paint channels respectively through the three paint passages.
8. The nozzle assembly according to claim 1, wherein: The outer diameter of the spray unit body is 8mm-90mm.
9. A process for spraying a surface coating in a hole, wherein the inner diameter of the hole to be sprayed is 10 mm to 100 mm, characterized in that: The nozzle assembly described in any one of claims 1-8 is inserted into the hole for spraying. During the process, the surface in the hole is evenly sprayed by selecting a suitable size of the spray port and controlling the air inlet pressure in the gas channel and the paint flow in the paint channel.
10. The spraying process of the in-hole profile coating according to claim 9, characterized in that: The equivalent circle radius of the spray port is 0.5mm-3mm, the air inlet pressure is 0.1-0.8Mpa, and the coating flow rate of each coating channel is 0.5-20g / s.