A spray head and wall painting equipment

Abstract

This invention relates to a printing head and wall painting equipment. The printing head includes a printhead body, a distance detection component, a posture adjustment component, and a multi-nozzle array module. The posture adjustment component includes a posture follower mechanism and a distance servo mechanism. In the posture follower mechanism, the movable part is supported on the fixed part via a two-dimensional rotating platform and has pitch and roll degrees of freedom. The distance servo mechanism is fixed on the movable part, and its driving end extends along the normal direction of the nozzle plate and is fixedly connected to the rear end of the printhead body. The distance detection component includes a first distance sensor and a second distance sensor, used to acquire tilt angle values ​​and normal distance values, respectively. When the front end of the printhead body contacts the target wall surface, the movable part drives the distance servo mechanism and the printhead body to deflect, achieving passive obstacle avoidance; the distance servo mechanism drives the printhead body to extend and retract along the normal direction, achieving active obstacle avoidance.

Description

Technical Field

[0001] This invention belongs to the technical field of art product equipment, specifically relating to a spray head and wall painting equipment. Background Technology

[0002] With the acceleration of urbanization and the continuous improvement of architectural aesthetics, wall painting, as an art form that combines decoration and culture, has been widely used in urban landscape beautification due to its advantages such as strong decorativeness, outstanding artistic expression, wide applicability, and good dissemination effect.

[0003] Wall painting technology, as an important branch of urban landscape beautification, uses automated mechanical devices to transfer preset patterns and colors to target walls, replacing traditional hand-painting. Wall painting equipment mainly consists of frame components, drive systems, inkjet control units, and inkjet heads. Among these, the inkjet head, as the execution terminal for performing inkjet actions, directly determines the printing quality based on the stability of its working state.

[0004] Existing inkjet printers and wall painting equipment typically employ a linear guide rail combined with a servo drive system. Specifically, the inkjet printer is rigidly fixed to a slider via a connector. A motor drives a synchronous belt or lead screw transmission mechanism, causing the slider to reciprocate horizontally along the linear guide rail, parallel to the target wall surface. Simultaneously, a separate drive mechanism provides synchronous control in the direction perpendicular to the target wall surface, thus forming the print trajectory of the printhead in a two-dimensional plane. The inkjet printer contains an array of nozzles that use piezoelectric ceramics to atomize ink particles and spray them onto the target wall surface to form the pattern.

[0005] However, in real-world scenarios, target walls are rarely perfectly flat, and their unevenness causes the distance between the printhead and the target surface to constantly change. When the distance is too large, the ink's flight path in the air is prolonged, easily causing scattering and diffusion, resulting in blurred pattern edges and decreased color fidelity. Conversely, when the distance is too small, the ink may not be fully atomized before contacting the surface, potentially leading to quality defects such as ink buildup and drips. Even more seriously, the printhead may collide with raised areas of the wall. Because the printhead integrates a nozzle array and other precision components, collisions can damage the printhead itself and cause a chain reaction of malfunctions, including ink leakage and short circuits, severely impacting work efficiency and increasing equipment maintenance costs.

[0006] Further analysis reveals that the existing solutions exhibit significant limitations when dealing with irregular surfaces due to the rigid connection structure between the printhead and the wall. While traditional distance sensing and adjustment mechanisms can detect and adjust distance changes within a certain range, their response speed and adjustment accuracy are limited. When the frequency or amplitude of wall undulations is high, existing closed-loop control systems struggle to achieve real-time, accurate distance tracking and motion feedback. This results in the printhead being unable to actively avoid wall protrusions or passively adapt to changes in the wall's contour upon contact, inevitably leading to collisions due to uncontrolled distance. Even with temperature and humidity control or multi-color nozzle arrays, the printhead cannot function stably due to dynamic fluctuations in the distance between it and the wall. Specifically, the ink viscosity consistency maintained by temperature and humidity control is offset by the continuous changes in droplet flight distance; similarly, the single-color registration accuracy of multi-color nozzles is severely degraded by the landing point offset caused by fluctuations in spray distance.

[0007] Therefore, how to enable the printing head to simultaneously possess the passive adaptability to wall undulations and the active tracking capability of the spraying distance is a key technical problem that urgently needs to be solved in this field. Building upon this, how to further integrate temperature and humidity environmental control with high-efficiency, multi-color printing, allowing each functional module to work collaboratively under the premise of dynamic distance stability, is also an important direction for improving the overall performance of wall painting equipment. Summary of the Invention

[0008] To address the aforementioned problems in the existing technology, this invention provides a printing head and wall painting equipment. The technical problem to be solved by this invention is achieved through the following technical solution: This invention provides a printhead, comprising: a printhead body, a distance detection component, a pose adjustment component, and a multi-nozzle array module; The printhead body includes an outer shell, an inkjet control unit disposed inside the outer shell, and multiple ink channels, which are respectively connected to an external ink supply pipeline to form an ink supply channel; a nozzle plate is provided at the front end of the outer shell, and a plurality of spray holes are formed on the nozzle plate in a matrix arrangement; The multi-orifice array module is integrated on the nozzle plate and includes at least three orifice sub-units. The ink flowing in the multiple ink supply channels is of different colors. Each orifice sub-unit corresponds to an ink supply channel of a different color, and the corresponding ink supply channel is connected to the plurality of orifices through the orifice sub-unit. The distance detection component includes multiple first distance sensors and second distance sensors. The multiple first distance sensors are disposed around the nozzle plate to detect the tilt angle value of the nozzle plate relative to the target wall. The second distance sensors are disposed on the central axis of the nozzle body, and the detection direction of the second distance sensors coincides with the normal direction of the nozzle plate to detect the normal distance value between the nozzle plate and the target wall. The pose adjustment component includes a pose follower mechanism and a distance servo mechanism. The pose follower mechanism includes a movable part, a fixed part, and a two-dimensional rotation platform. The fixed part is connected to an external input end. The two-dimensional rotation platform is located between the movable part and the fixed part. The movable part is supported on the fixed part by the two-dimensional rotation platform, and the movable part has pitch and roll degrees of freedom relative to the fixed part. The distance servo mechanism is fixed on the movable part. The driving end of the distance servo mechanism extends along the normal direction of the nozzle plate and is fixedly connected to the rear end of the nozzle body. The driving end can extend and retract along the normal direction of the nozzle plate to adjust the distance between the nozzle plate and the target wall to achieve active obstacle avoidance. When the front end of the nozzle body contacts the target wall, the movable part drives the distance servo mechanism and the nozzle body to deflect around the two-dimensional rotating platform to achieve passive obstacle avoidance.

[0009] In one embodiment of the present invention, the rear end of the nozzle body is provided with an installation interface, and the installation interface is fixedly connected to the drive end of the distance servo mechanism. The mounting interface includes a positioning keyway and a positioning pin hole. A sealing ring groove is provided on the mating surface of the mounting interface, and a sealing ring is embedded in the sealing ring groove.

[0010] In one embodiment of the present invention, the two-dimensional rotating platform includes a first pivot axis, a second pivot axis, and an intermediate support. The first pivot axis and the second pivot axis are arranged alternately, and the two ends of the first pivot axis are respectively supported on the fixed part and the intermediate support, so that the intermediate support can roll relative to the fixed part. The two ends of the second pivot shaft are respectively supported on the intermediate support and the movable part, so that the movable part can pitch relative to the intermediate support; Springs are connected to the first pivot shaft and the second pivot shaft respectively. The first movable end of the spring is connected to the fixed part or the movable part, and the second movable end is connected to the first pivot shaft or the second pivot shaft.

[0011] In one embodiment of the present invention, the first distance sensor is an infrared ranging sensor, and at least four infrared ranging sensors are provided and respectively arranged at the four corners of the nozzle plate; The detection direction of each infrared ranging sensor is at a 30° angle to the normal direction of the nozzle plate, and is used to detect the tilt angle value of the nozzle plate relative to the target wall. The second distance sensor is an infrared ranging sensor, used to detect the normal distance between the nozzle plate and the target wall. The printing head also includes a control unit. Multiple first distance sensors and second distance sensors are electrically connected to the control unit. The control unit is electrically connected to the distance servo mechanism and is used to control the extension and retraction of the drive end of the distance servo mechanism according to the tilt angle value and the normal distance value, so as to adjust the distance between the nozzle plate and the target wall to achieve active obstacle avoidance.

[0012] In one embodiment of the present invention, at least three nozzle sub-units in the multi-nozzle array module are arranged sequentially, namely a cyan nozzle sub-unit, a magenta nozzle sub-unit, and a yellow nozzle sub-unit; the cyan nozzle sub-unit is located in the middle position, and the magenta and yellow nozzle sub-units are symmetrically arranged on both sides of the cyan nozzle sub-unit; Among them, at least three of the nozzle sub-units are configured such that, during the reciprocating motion of the printing head, the start-up, stop, and timing of each nozzle sub-unit are independently controlled.

[0013] In one embodiment of the present invention, the inkjet head further includes an anti-collision protection component; the anti-collision protection component includes a protective sleeve and a pressure sensing band; The protective sleeve is fitted around the outer periphery of the nozzle plate, and a reserved gap is provided between the inner wall of the protective sleeve and the outer edge of the nozzle plate; the protective sleeve is made of silicone material and at least partially protrudes from the front end of the nozzle plate, so that the protective sleeve contacts the target wall surface before the front end of the nozzle plate; The pressure sensing strip is attached to the inner wall of the protective sleeve. The pressure sensing strip is electrically connected to the control unit. The pressure sensing strip is a piezoresistive thin-film sensor used to acquire pressure signals. When the protective sleeve comes into contact with the target wall, the movable part passively deflects around the two-dimensional rotating platform, driving the distance servo mechanism and the nozzle body to rotate in accordance with the contour of the target wall to achieve passive obstacle avoidance; The control unit is used to compare the pressure signal with a preset pressure threshold. When the pressure signal exceeds the preset pressure threshold, it determines that a collision has occurred and obtains a collision signal. The control unit is also used to control the drive end to extend and retract along the normal direction of the nozzle plate according to the collision signal, so as to adjust the distance between the nozzle plate and the target wall to achieve emergency obstacle avoidance.

[0014] In one embodiment of the present invention, the distance servo mechanism includes a voice coil motor, the stator of the voice coil motor is fixed on the movable part, and the mover of the voice coil motor serves as the driving end of the distance servo mechanism and is connected to the mounting interface of the nozzle body. The voice coil motor responds to the collision signal from the control unit, driving the nozzle body to retract in a direction away from the target wall to achieve emergency obstacle avoidance.

[0015] In one embodiment of the present invention, the print head further includes a cleaning assembly; the cleaning assembly includes a cleaning fluid storage tank disposed on the side of the print head body, a cleaning pump connected to the storage tank, and a cleaning nozzle; The degree of blockage of the nozzle is determined based on the spray response time of the nozzle. When the spray response time exceeds a preset normal value, it is determined that the nozzle is blocked. The cleaning pump is configured to start when a preset condition is met, and spray the cleaning liquid in the cleaning liquid storage tank onto the surface of the nozzle through the cleaning nozzle. The preset conditions include reaching a preset cleaning cycle or the nozzle becoming clogged.

[0016] In one embodiment of the present invention, the inkjet head further includes: a temperature and humidity control component, the temperature and humidity control component including a heat insulation layer covering the outer wall of the printhead body, a heating film attached to the outside of the ink cavity, a temperature sensor and a humidity sensor disposed inside the printhead body, and a temperature control module electrically connected to the temperature sensor and the humidity sensor respectively. The temperature sensor is used to detect the temperature inside the printhead body to obtain a temperature detection value, and the temperature control module is used to adjust the heating power of the heating film according to the temperature detection value to adjust the ink temperature in the ink cavity. The humidity sensor is used to detect the relative humidity inside the nozzle body to obtain a humidity detection value. The temperature control module is also used to increase the heating power of the heating film according to the humidity detection value, so as to reduce the relative humidity inside the nozzle body.

[0017] The present invention also provides a wall painting equipment, including a frame assembly, a drive system, a main control system, and the aforementioned printing head; The frame assembly includes a horizontal guide rail, a vertical guide rail, and a movable slider. The vertical guide rail is disposed on the horizontal guide rail and can slide horizontally along the horizontal guide rail. The movable slider is disposed on the vertical guide rail and can slide along the vertical guide rail. The movable slider serves as an external input end, and the inkjet head is mounted on the movable slider via the fixing part of the posture follow-up mechanism; The drive system includes a horizontal drive motor, a vertical drive motor, a horizontal transmission mechanism, and a vertical transmission mechanism; the horizontal drive motor drives the vertical guide rail to slide along the horizontal guide rail through the horizontal transmission mechanism; the vertical drive motor drives the movable slider and the inkjet head to slide along the vertical guide rail through the vertical transmission mechanism. The main control system includes an image processing unit and a printing control unit. The image processing unit is used to perform color separation, ink volume calculation and printing timing arrangement on the input bitmap image to obtain a printing data file. The printing control unit is used to generate drive signals for each nozzle sub-unit according to the printing data file and transmit them to the printing head.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The inkjet head of the present invention includes a printhead body, a distance detection component, a pose adjustment component, and a multi-nozzle array module. The pose adjustment component comprises a posture follower mechanism and a distance servo mechanism connected in series. The posture follower mechanism has a movable part, a fixed part, and a two-dimensional rotating platform connecting the two. The movable part is supported on the fixed part by the two-dimensional rotating platform. The distance servo mechanism is fixedly mounted on the movable part, and its driving end extends along the normal direction of the nozzle plate and is fixedly connected to the rear end of the printhead body. In the distance detection component, a first distance sensor is arranged around the nozzle plate to obtain tilt angle values, and a second distance sensor is located on the central axis of the printhead body with its detection direction coinciding with the normal direction of the nozzle plate to obtain normal distance values. During printing, when the front end of the printhead comes into contact with a protruding area of ​​the target wall, the wall's reaction force is transmitted to the moving part via the printhead body and the distance servo mechanism. The moving part causes the printhead body to pitch or roll around a two-dimensional rotating platform, allowing the printhead body to change its posture according to the wall's contour, achieving passive obstacle avoidance. Simultaneously, the distance detection component, based on the tilt angle and normal distance values, moves the printhead body closer to or further away from the wall to compensate for changes in the spraying distance between the nozzle plate and the wall, achieving active obstacle avoidance and distance tracking. With this structure, passive posture compliance and active distance adjustment are mechanically connected but independent in motion response, enabling the printhead to simultaneously possess the ability to passively conform to the wall contour and actively maintain the spraying distance.

[0019] The inkjet head of this invention also includes an anti-collision protection component, a cleaning component, and a temperature and humidity control component. In the anti-collision protection component, a soft protective sleeve contacts the wall surface before the nozzle plate, providing a buffer contact for passive obstacle avoidance. When the contact pressure exceeds a preset pressure threshold, the pressure sensing strip on its inner wall outputs a collision signal, triggering a distance servo mechanism to drive the printhead body to retract, thus achieving emergency obstacle avoidance. The cleaning component determines the clogging status by monitoring the spray response time of the nozzles and starts the cleaning pump for automatic cleaning based on the clogging status. In the temperature and humidity control component, a temperature sensor and a humidity sensor detect the ink temperature and the relative humidity inside the printhead body, respectively, and then adjust them through a heating film. In the multi-nozzle array module, nozzle sub-units of different colors are arranged in parallel. Each nozzle sub-unit independently controls the start and stop sequence according to the color ratio in the same reciprocating motion, so that each color ink can be sprayed synchronously to complete the pattern printing in a single stroke.

[0020] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a printing head provided in an embodiment of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the inkjet head provided in an embodiment of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the internal structure of the nozzle body provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the pose adjustment component provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the distance servo mechanism provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the nozzle body, anti-collision protection component, and cleaning component provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the cleaning assembly provided in an embodiment of the present invention; Figure 8 This is a structural schematic diagram of a printing equipment provided in an embodiment of the present invention; Figure 9 This is a structural schematic diagram of the rack assembly provided in an embodiment of the present invention.

[0022] Reference numerals: 1-Printhead body; 11-Outer shell; 111-Nozzle plate; 12-Inkjet control unit; 2-Distance detection component; 21-First distance sensor; 22-Second distance sensor; 3-Position adjustment component; 31-Attitude follow-up mechanism; 311-Moving part; 312-Fixed part; 313-Two-dimensional rotating platform; 3131-First pivot axis; 3132-Second pivot axis; 3133-Intermediate support; 314-Spring; 32-Distance servo mechanism; 321-Voice coil motor; 322-Drive end; 4-Multi-nozzle array module; 5-Anti-collision protection component; 51-Protective sleeve; 6-Cleaning component; 61-Cleaning fluid storage tank; 62-Cleaning pump; 63-Cleaning nozzle; 100-Frame assembly; 110-Horizontal guide rail; 120-Vertical guide rail; 130-Moving slider; 200-Drive system; 300-Main control system. Detailed Implementation

[0023] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description of a printing head and wall painting equipment according to the present invention is provided in conjunction with the accompanying drawings and specific embodiments.

[0024] The foregoing and other technical contents, features, and effects of the present invention will be clearly presented in the following detailed description of specific embodiments in conjunction with the accompanying drawings. Through the description of the specific embodiments, a more in-depth and concrete understanding can be gained of the technical means and effects adopted by the present invention to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit the technical solutions of the present invention.

[0025] Example 1 like Figures 1 to 7 As shown, Figure 1 This is a schematic diagram of the structure of a printing head provided in an embodiment of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the inkjet head provided in an embodiment of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the internal structure of the nozzle body provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the pose adjustment component provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the distance servo mechanism provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the nozzle body, anti-collision protection component, and cleaning component provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the cleaning assembly provided in an embodiment of the present invention.

[0026] This embodiment provides a printhead, including a printhead body 1, a distance detection component 2, a pose adjustment component 3, and a multi-nozzle array module 4.

[0027] The printhead body 1 includes a housing 11, an inkjet control unit 12 disposed inside the housing 11, and multiple ink channels. These ink channels are connected to external ink supply lines to form ink supply channels. A nozzle plate 111 is located at the front end of the housing 11, and several nozzles are arranged in a matrix on the nozzle plate 111. A multi-nozzle array module 4 is integrated on the nozzle plate 111, and includes at least three nozzle sub-units. The ink flowing in the multiple ink supply channels corresponds to different colors, and each nozzle sub-unit corresponds to a different color ink supply channel. The nozzle sub-units connect the corresponding ink supply channel to the multiple nozzles. The inkjet control unit 12 is connected to each nozzle sub-unit and controls the corresponding nozzle sub-unit according to the printing data. It is understood that the inkjet control unit 12 can be a piezoelectric inkjet printhead; its specific model, internal structure, and driving principle are existing technologies and will not be described in detail here. With the above structure, inks of different colors are delivered to their respective nozzles through their respective ink supply channels and nozzle sub-units, providing an independent ink supply path for multi-color inkjet printing.

[0028] In one specific implementation, an ink cartridge may also be provided inside the outer casing 11, and the ink cartridge is connected to multiple ink channels to form an ink supply channel.

[0029] The distance detection component 2 includes multiple first distance sensors 21 and second distance sensors 22. The first distance sensors 21 are arranged around the nozzle plate 111 to detect the tilt angle of the nozzle plate 111 relative to the target wall. The second distance sensors 22 are arranged on the central axis of the nozzle body 1, and the detection direction of the second distance sensors 22 coincides with the normal direction of the nozzle plate 111 to detect the normal distance between the nozzle plate 111 and the target wall. With the above arrangement, the tilted first distance sensors 21 detect changes in the wall angle, and the vertically arranged second distance sensors 22 detect changes in the normal distance, thus forming a complementary effect in spatial layout.

[0030] The pose adjustment component 3 includes a pose follower mechanism 31 and a distance servo mechanism 32. The pose follower mechanism 31 includes a movable part 311, a fixed part 312, and a two-dimensional rotating platform 313. The fixed part 312 is connected to an external input end, and the two-dimensional rotating platform 313 is located between the movable part 311 and the fixed part 312. The movable part 311 is supported on the fixed part 312 by the two-dimensional rotating platform 313, and the movable part 311 has pitch and roll degrees of freedom relative to the fixed part 312. When the front end of the nozzle body 1 contacts the target wall, the movable part 311 drives the distance servo mechanism 32 and the nozzle body 1 to deflect around the two-dimensional rotating platform 313 to achieve passive obstacle avoidance. The distance servo mechanism 32 is fixedly mounted on the movable part 311. The drive end 322 of the distance servo mechanism 32 extends along the normal direction of the nozzle plate 111 and is fixedly connected to the rear end of the nozzle body 1. The drive end 322 can extend and retract along the normal direction of the nozzle plate 111 to adjust the distance between the nozzle plate 111 and the target wall to achieve active obstacle avoidance. With the above structure, the attitude follower mechanism 31 is used for passive attitude compliance, and the distance servo mechanism 32 is used for active distance adjustment. The two are connected in series in mechanical structure but independent of each other in motion response and do not interfere with each other.

[0031] In this embodiment, the rear end of the nozzle body 1 is provided with an installation interface, which is fixedly connected to the drive end 322 of the distance servo mechanism 32. Specifically, the installation interface includes a positioning keyway and a positioning pin hole, and a sealing ring groove is provided on the mating surface of the installation interface, with a sealing ring embedded in the sealing ring groove. The positioning keyway and positioning pin hole ensure the installation accuracy between the nozzle body 1 and the drive end 322; the sealing ring embedded in the sealing ring groove prevents external dust and moisture from entering the connection interface.

[0032] The two-dimensional rotating platform 313 includes a first pivot shaft 3131, a second pivot shaft 3132, and an intermediate support 3133. The first pivot shaft 3131 and the second pivot shaft 3132 are staggered. The two ends of the first pivot shaft 3131 are supported on the fixed part 312 and the intermediate support 3133, respectively, allowing the intermediate support 3133 to roll relative to the fixed part 312. The two ends of the second pivot shaft 3132 are supported on the intermediate support 3133 and the movable part 311, respectively, allowing the movable part 311 to pitch relative to the intermediate support 3133. Springs 314 are connected to the first pivot shaft 3131 and the second pivot shaft 3132, respectively. The first movable end of the spring 314 is connected to either the fixed part 312 or the movable part 311, and its second movable end is connected to either the first pivot shaft 3131 or the second pivot shaft 3132. Through the first pivot 3131 and the second pivot 3132, the movable part 311 obtains two independent rotational degrees of freedom: pitch and roll. The spring 314 provides an elastic restoring force when the movable part 311 deflects, so that the movable part 311 returns to the neutral position after the external force disappears.

[0033] In one specific implementation, the fixed part 312 serves as the mounting base for the inkjet head, and is fixedly connected to the external moving input end via bolts or a mounting bracket. The first pivot axis 3131 and the second pivot axis 3132 are spatially intersecting, corresponding to the roll and pitch degrees of freedom, respectively. Specifically, the first pivot axis 3131 is rotatably connected to the fixed part 312 via a bearing, allowing the first pivot axis 3131 to rotate around its rotational connection axis on the fixed part 312. The intermediate support 3133 is a frame structure, with a connecting part in its middle that mates with the first pivot axis 3131. The intermediate support 3133 is connected to the first pivot axis 3131 via its connecting part, allowing the intermediate support 3133 to rotate with the first pivot axis 3131 to achieve roll. One of the springs 314 has its two movable ends connected to the fixed part 312 and the first pivot shaft 3131, respectively. When the intermediate support 3133 rolls, the spring 314 stretches or compresses. When the external force disappears, the spring 314 releases the accumulated elastic potential energy, driving the intermediate support 3133 to return to its initial neutral position. Similarly, the second pivot shaft 3132 is supported by a bearing in the mounting hole of the intermediate support 3133, and the axes of the second pivot shaft 3132 and the first pivot shaft 3131 are spatially intersected. The movable part 311 is provided with a connecting part that mates with the second pivot shaft 3132. The movable part 311 is connected to the second pivot shaft 3132 through its connecting part, so that the movable part 311 can rotate with the second pivot shaft 3132 to achieve pitch. The two movable ends of another spring 314 are respectively connected to the movable part 311 and the second pivot shaft 3132. When the movable part 311 pitches, the spring 314 is stretched or compressed. When the external force disappears, the accumulated elastic potential energy is released through the spring 314, driving the movable part 311 to return to the initial neutral position.

[0034] In an optional embodiment, the first distance sensor 21 can be an infrared ranging sensor, with at least four infrared ranging sensors arranged at the four corners of the nozzle plate 111. Preferably, the detection direction of each infrared ranging sensor forms a 30° angle with the normal direction of the nozzle plate 111, used to detect the tilt angle value of the nozzle plate 111 relative to the target wall. Using a 30° tilt angle can improve the sensor's sensitivity to changes in the angle between the nozzle plate 111 and the target wall, while balancing the ranging range and measurement accuracy. Understandably, when the nozzle plate 111 tilts relative to the target wall, the distance values ​​measured by the sensors located at the four corners of the nozzle plate 111 will differ. The control unit, based on the difference in tilt angle values ​​measured by the four sensors, combined with the geometric installation position of the nozzle plate 111 and the detection direction angle of each sensor, can calculate the pitch angle and roll angle of the nozzle plate 111 relative to the target wall using spatial geometric relationships to obtain the tilt angle value.

[0035] In an optional implementation, the second distance sensor 22 can be an infrared rangefinder sensor used to detect the normal distance between the nozzle plate 111 and the target wall.

[0036] Furthermore, the printing head also includes a control unit. Multiple first distance sensors 21 and second distance sensors 22 are electrically connected to the control unit. The control unit is electrically connected to a distance servo mechanism 32 and is used to control the extension and retraction of the drive end 322 of the distance servo mechanism 32 based on the tilt angle value and the normal distance value, thereby adjusting the distance between the nozzle plate 111 and the target wall to achieve active obstacle avoidance. The control unit can be integrated inside the printing head or can be independently located externally and electrically connected to each sensor and the distance servo mechanism 32 via wired or wireless means.

[0037] In one optional implementation, in the multi-nozzle array module 4, nozzle sub-units of different colors are arranged in parallel, and the start and stop sequence of each nozzle sub-unit is independently controlled according to the color ratio during the same reciprocating motion. Preferably, at least three nozzle sub-units in the multi-nozzle array module 4 are arranged sequentially, namely a cyan nozzle sub-unit, a magenta nozzle sub-unit, and a yellow nozzle sub-unit. Specifically, the cyan nozzle sub-unit is located in the middle position, and the magenta and yellow nozzle sub-units are symmetrically arranged on both sides of the cyan nozzle sub-unit. The at least three nozzle units are configured such that during the reciprocating motion of the print head, the start, stop, and timing of each nozzle sub-unit are independently controlled, such as each nozzle unit being controlled by a set of independent piezoelectric drive signal lines, so that the inks of different colors can be synchronously sprayed to the corresponding positions on the target wall in the same reciprocating motion, realizing the synchronous printing of multi-color patterns in a single stroke without the need for multiple color matching operations.

[0038] It is worth noting that the inkjet head of the present invention includes a printhead body 1, a distance detection component 2, a pose adjustment component 3, and a multi-nozzle array module 4. The pose adjustment component 3 is composed of a posture follower mechanism 31 and a distance servo mechanism 32 connected in series. The posture follower mechanism 31 has a movable part 311, a fixed part 312, and a two-dimensional rotating platform 313 connected between the two. The movable part 311 is supported on the fixed part 312 via the two-dimensional rotating platform 313. The distance servo mechanism 32 is fixedly mounted on the movable part 311, and its driving end 322 extends along the normal direction of the nozzle plate 111 and is fixedly connected to the rear end of the printhead body 1. In the distance detection component 2, a first distance sensor 21 is arranged around the nozzle plate 111 to obtain tilt angle values, and a second distance sensor 22 is located on the central axis of the printhead body 1 with its detection direction coinciding with the normal direction of the nozzle plate 111 to obtain normal distance values. During printing, if the front end of the printhead body 1 contacts a protruding area of ​​the target wall, the wall reaction force is transmitted to the movable part 311 via the printhead body 1 and the distance servo mechanism 32. The movable part 311 drives the printhead body 1 to pitch or roll around the two-dimensional rotating platform 313, allowing the printhead body 1 to change its posture according to the wall contour, thus achieving passive obstacle avoidance. At the same time, the distance detection component 2 moves the printhead body 1 closer to or further away from the wall based on the tilt angle and normal distance values ​​to compensate for changes in the spraying distance between the nozzle plate 111 and the wall, thus achieving active obstacle avoidance and distance tracking. With this structure, passive posture compliance and active distance adjustment are mechanically connected in series but independent in motion response, enabling the printhead to simultaneously possess the ability to passively conform to the wall contour and the ability to actively maintain the spraying distance.

[0039] Example 2 This embodiment further explains the anti-collision protection component 5 based on the first embodiment.

[0040] In this embodiment, the printing head further includes an anti-collision protection component 5, which includes a protective sleeve 51 and a pressure sensing strip. The protective sleeve 51 is fitted around the outer periphery of the nozzle plate 111, and a pre-reserved gap is provided between the inner wall of the protective sleeve 51 and the outer edge of the nozzle plate 111. The protective sleeve 51 is made of silicone material and at least partially protrudes from the front end of the nozzle plate 111, so that the protective sleeve 51 contacts the target wall surface before the front end of the nozzle plate 111. The pressure sensing strip is attached to the inner wall of the protective sleeve 51 and is electrically connected to the control unit. Preferably, the pressure sensing strip can be a piezoresistive thin-film sensor for acquiring pressure signals.

[0041] When the protective sleeve 51 contacts the target wall, the movable part 311 passively deflects around the two-dimensional rotating platform 313, driving the distance servo mechanism 32 and the nozzle body 1 to rotate in accordance with the contour of the target wall to achieve passive obstacle avoidance. The control unit is used to compare the pressure signal with a preset pressure threshold. When the pressure signal exceeds the preset pressure threshold, it determines that a collision has occurred and obtains a collision signal. The preset pressure threshold can be determined comprehensively based on the weight of the nozzle body 1, the stiffness of the spring 314, and the safe distance between the nozzle plate 111 and the target wall. This embodiment does not impose any restrictions on this. The control unit is also used to control the drive end 322 to extend and retract along the normal direction of the nozzle plate 111 according to the collision signal, so as to adjust the distance between the nozzle plate 111 and the target wall to achieve emergency obstacle avoidance.

[0042] Preferably, the protective sleeve 51 has a ring structure and is fitted around the outer periphery of the nozzle plate 111, with its front end protruding from the surface of the nozzle plate 111; the protective sleeve 51 may be made of silicone material and has elastic deformation capability to provide cushioning when in contact with the wall.

[0043] It is worth noting that the protective sleeve 51 forms a flexible protective barrier between the nozzle plate 111 and the wall. The protective sleeve 51 contacts the wall before the nozzle plate 111, providing an initial contact point and buffer for passive obstacle avoidance. Furthermore, the reserved gap, i.e., its own elastic deformation, protects the nozzle plate 111 from direct impact. When the protective sleeve 51 experiences abnormal contact pressure due to severe wall undulations, the pressure signal detected by the pressure sensor exceeds the threshold. The control unit then triggers emergency obstacle avoidance, driving the nozzle body 1 to actively retract, thus achieving emergency obstacle avoidance.

[0044] Example 3 This embodiment further describes the cleaning component 6 based on the above embodiment.

[0045] In this embodiment, the printhead also includes a cleaning assembly 6, which includes a cleaning fluid storage tank 61 located on the side of the printhead body 1, a cleaning pump 62 connected to the storage tank, and a cleaning nozzle 63. The degree of nozzle blockage is determined based on the nozzle ejection response time. When the ejection response time exceeds a preset normal value, the nozzle is judged to be blocked. The preset normal value can be determined based on the nozzle diameter, the ink viscosity in the ink channel, and the standard ejection response time under normal operating conditions. The ejection response time can be the time difference between the energization of the piezoelectric element and the ejection of ink droplets from the corresponding nozzle. The specific value of the preset normal value is not limited in this embodiment.

[0046] The cleaning pump 62 is configured to start when preset conditions are met, spraying the cleaning fluid from the cleaning fluid storage tank 61 onto the surface of the nozzle through the cleaning nozzle 63. The preset conditions include reaching a preset cleaning cycle or the nozzle becoming clogged; wherein, the preset cleaning cycle can be determined based on the cumulative working time of the inkjet head, the sedimentation characteristics of the ink in the ink supply channel, and the dust concentration of the working environment, and this embodiment does not impose any limitations on this.

[0047] In one specific embodiment, the cleaning fluid storage tank 61 and the cleaning pump 62 are both fixed to the outer side wall of the nozzle body 1, and their installation positions do not exceed the lateral contour range of the nozzle body 1. The cleaning fluid storage tank 61, the cleaning pump 62, and the cleaning nozzle 63 are connected in series via a flexible fluid supply pipeline. Specifically, the outer side wall of the nozzle body 1 is also provided with a slide rail, the extension direction of which is parallel to the normal direction of the nozzle plate 111. A slider that slides along the slide rail is provided on the slide rail, and the slider is driven by a micro-drive component to slide back and forth along the slide rail. The micro-drive component is electrically connected to the control unit, and its operation timing is controlled by the control unit.

[0048] Furthermore, a swing arm is hinged to the slider, and the swing arm can swing relative to the slider in a plane parallel to the nozzle plate 111. The cleaning nozzle 63 is fixed to the free end of the swing arm, and an elastic reset member is provided between the swing arm and the slider. The elastic reset member is used to hold the swing arm at a retractable angle. At this retractable angle, the swing arm and the cleaning nozzle 63 are retracted within the side profile of the nozzle body 1. A guide block is provided on the front side of the nozzle body 1. The guide block is located at the front end of the slide rail and abuts against the swing arm. When the slider slides forward along the slide rail beyond the range of the slide rail, the swing arm disengages from the guide block, and the swing arm swings outward under the elastic force of the elastic reset member, causing the cleaning nozzle 63 to move from the side of the nozzle body 1 to the front of the nozzle plate 111.

[0049] In other words, when the printhead is in normal printing operation, the slider is located at the rear end of the slide rail, and the swing arm is held at the retracted angle by the elastic reset component. The cleaning nozzle 63 is completely retracted within the side profile of the printhead body 1 and does not protrude from the front end of the nozzle plate 111, so it will not interfere with the target wall or the nozzle plate 111. At this time, the entire cleaning assembly 6 moves together with the printhead body 1 under the drive of the distance servo mechanism 32, without affecting normal printing operation.

[0050] When preset conditions are met, the control unit first retracts the drive end 322 of the distance servo mechanism 32, causing the nozzle body 1 to retract as a whole. Then, it controls the micro-drive component to drive the slider to slide forward along the slide rail. The slider drives the swing arm and the cleaning nozzle 63 to move forward together. When the slider slides to the front end of the slide rail, the swing arm contacts the guide block and swings outward under the guidance of the guide block, causing the cleaning nozzle 63 to move from the side of the nozzle body 1 to the front of the nozzle plate 111 and align with the nozzle hole. Then, the cleaning pump 62 is started, and the cleaning fluid in the cleaning fluid storage tank 61 is delivered to the cleaning nozzle 63 through the flexible supply pipeline, and then sprayed onto the nozzle hole surface by the cleaning nozzle 63 for cleaning. It is worth noting that by monitoring the spray response time to determine the degree of blockage, the working status of the nozzle hole can be known in real time without disassembling the nozzle. When blockage is determined, the cleaning pump 62 is started to spray the cleaning fluid evenly onto the nozzle hole surface through the cleaning nozzle 63, realizing automatic cleaning and maintenance and extending the maintenance-free working time of the nozzle.

[0051] Example 4 This embodiment further describes the temperature and humidity control component based on the above embodiments.

[0052] In this embodiment, the printhead further includes a temperature and humidity control component (not shown in the figure). The temperature and humidity control component includes a heat insulation layer covering the outer wall of the printhead body 1, a heating film attached to the outside of the ink channel, a temperature sensor and a humidity sensor disposed inside the printhead body 1, and a temperature control module electrically connected to the temperature sensor and humidity sensor respectively. The temperature sensor detects the temperature inside the printhead body 1 to obtain a temperature detection value. The temperature control module adjusts the heating power of the heating film according to the temperature detection value to regulate the ink temperature inside the ink channel. The humidity sensor detects the relative humidity inside the printhead body 1 to obtain a humidity detection value. The temperature control module also increases the heating power of the heating film according to the humidity detection value to reduce the relative humidity inside the printhead body 1.

[0053] During the inkjet printing process, if the ink temperature is too low, the ink viscosity will increase, causing poor spraying or nozzle blockage. If the temperature is too high, it may cause changes in the chemical composition of the ink, affecting the consistency and stability of the color. If the humidity inside the printhead body 1 is too high, the ink is prone to condensation on the surface of non-spraying areas, resulting in short circuits or ink accumulation around the nozzles.

[0054] Therefore, in this embodiment, an insulation layer is used to cover the outer wall of the printhead body 1 to reduce the influence of the external ambient temperature on the internal temperature of the printhead; a heating film is attached to the outside of the ink cavity, and heat is directly transferred to the ink cavity. Temperature and humidity sensors detect the ink temperature and internal relative humidity, respectively. The temperature control module adjusts the heating power of the heating film according to the detected values ​​to maintain a stable ink temperature when the temperature deviates from the preset temperature range, and to reduce the internal relative humidity by increasing the heating power when the humidity is higher than the preset humidity threshold.

[0055] Understandably, the preset temperature range can be determined based on the ideal ejection viscosity of the ink within the ink cavity. The lower limit of the preset temperature range is the lowest temperature at which the ink can be ejected smoothly without clogging, and the upper limit is the highest temperature at which the ink will not undergo chemical changes or bubble formation due to high temperatures. When the temperature detected by the temperature sensor deviates from the preset temperature range, the temperature control module adjusts the heating power of the heating film to restore the ink temperature to within that range. Similarly, the preset humidity threshold can be determined based on the moisture resistance rating of the electronic components inside the printhead body 1 and the critical relative humidity for ink condensation in non-ejection areas. When the relative humidity detected by the humidity sensor exceeds the preset humidity threshold, the temperature control module increases the heating power of the heating film to reduce the relative humidity inside the printhead body 1.

[0056] In this way, the posture adjustment component 3 maintains a dynamic and stable spray distance between the nozzle plate 111 and the target wall through passive obstacle avoidance and active obstacle avoidance, ensuring the consistency of the ink droplet flight path; the temperature and humidity control component adjusts the ink temperature and internal relative humidity to ensure the consistency of the initial velocity and volume of the ink droplets, thereby ensuring the accuracy of the ink droplet landing point and the color reproduction on the target wall.

[0057] Example 5 like Figure 8 and Figure 9 As shown, Figure 8 This is a structural schematic diagram of a printing equipment provided in an embodiment of the present invention; Figure 9 This is a structural schematic diagram of the rack assembly provided in an embodiment of the present invention.

[0058] This embodiment provides a wall painting equipment, including a frame assembly 100, a drive system 200, a main control system 300, and a printing head of any of the aforementioned embodiments.

[0059] The frame assembly 100 includes a horizontal guide rail 110, a vertical guide rail 120, and a movable slider 130. The vertical guide rail 120 is mounted on the horizontal guide rail 110 and can slide horizontally along the horizontal guide rail 110. The movable slider 130 is mounted on the vertical guide rail 120 and can slide along the vertical guide rail 120. The movable slider 130 serves as an external input end, and the inkjet head is mounted on the movable slider 130 via the fixing part 312 of the attitude follower mechanism 31. The drive system 200 includes a horizontal drive motor, a vertical drive motor, a horizontal transmission mechanism, and a vertical transmission mechanism. The horizontal drive motor drives the vertical guide rail 120 to slide along the horizontal guide rail 110 via the horizontal transmission mechanism, and the vertical drive motor drives the movable slider 130 and the inkjet head to slide along the vertical guide rail 120 via the vertical transmission mechanism.

[0060] The main control system 300 includes an image processing unit and a printing control unit. The image processing unit is used to perform color separation, ink volume calculation and printing timing arrangement on the input bitmap image to obtain a printing data file. The printing control unit is used to generate drive signals for each nozzle sub-unit according to the printing data file and transmit them to the printing head.

[0061] In one specific implementation, the inkjet control unit 12 inside the printhead body 1 is electrically connected to the inkjet control unit of the main control system 300, and is used to receive drive signals and independently control the start, stop and timing of each nozzle sub-unit according to the inkjet data file to realize the synchronous spraying of multi-color inks.

[0062] With the cooperation of the frame assembly 100 and the drive system 200, the printing head can perform two-dimensional movement in both the horizontal and vertical directions, thereby covering the entire working area of ​​the target wall. The main control system 300 converts the image data into independent drive signals for each nozzle sub-unit, realizing the printing output of the pattern.

[0063] It should be noted that the inkjet printing equipment provided in this embodiment includes the inkjet head of any of the foregoing embodiments, and therefore has similar beneficial effects to any of the foregoing embodiments. For technical details not disclosed in this embodiment, please refer to the description of any of the foregoing embodiments for clarification.

[0064] Example 6 This embodiment provides supplementary explanations of the specific working process of the inkjet head of the present invention in three scenarios: passive obstacle avoidance, active obstacle avoidance, and emergency obstacle avoidance, so that those skilled in the art can more fully understand the present invention.

[0065] During the printing process, the print head moves horizontally back and forth with the slider 130, conforming to the target wall surface. At the same time, the nozzles on the nozzle plate 111 spray ink according to a preset sequence to form a pattern. The distance detection component 2 works in real time. The first distance sensor 21 obtains the tilt angle value of the nozzle plate 111 relative to the target wall surface, and the second distance sensor 22 obtains the normal distance value between the nozzle plate 111 and the target wall surface.

[0066] When the target wall surface has a macroscopic undulating contour, the protective sleeve 51 fitted around the nozzle plate 111 first contacts the protruding area of ​​the wall surface. The reaction force from the wall surface is transmitted to the movable part 311 through the protective sleeve 51 or the nozzle body 1, causing the movable part 311 to move around the two-dimensional rotating platform 313. This drives the distance servo mechanism 32 and the nozzle body 1 to adapt to the changes in the wall surface contour, achieving passive obstacle avoidance. During passive obstacle avoidance, the movable part 311 deflects to compress or stretch the spring 314. The spring 314 provides elastic restoring force, allowing the nozzle body 1 to automatically return to the neutral position after the wall surface protrudes. The passive obstacle avoidance process requires no sensor signal or control system intervention, has no response delay, and is suitable for scenarios where the wall surface contour is flat and continuously changing. In addition, during passive obstacle avoidance, the drive end 322 of the distance servo mechanism 32 remains unchanged in its current extension and retraction position and does not actively perform extension and retraction actions, so that the reaction force from the target wall surface can be transmitted to the movable part 311 through the nozzle body 1.

[0067] Meanwhile, the distance servo mechanism 32 drives its drive end 322 to actively extend and retract along the normal direction of the nozzle plate 111 based on the normal distance value obtained by the second distance sensor 22, thereby driving the nozzle body 1 to move closer to or away from the target wall to compensate for the change in spray distance caused by local undulations of the wall and maintain the distance between the nozzle plate 111 and the target wall to achieve active obstacle avoidance.

[0068] When the wall protrusion increases abnormally and the force on the protective sleeve 51 exceeds the normal range, the pressure signal acquired by the pressure sensing strip attached to the inner wall of the protective sleeve 51 exceeds the preset pressure threshold. After comparing the pressure signal with the preset pressure threshold, the control unit determines that a collision has occurred and obtains a collision signal. Based on the collision signal, the control unit controls the drive end 322 of the distance servo mechanism 32 to retract in a direction away from the target wall, driving the nozzle body 1 to retreat to a safe position to achieve emergency obstacle avoidance.

[0069] It is worth noting that the inkjet head and wall painting equipment of the present invention employ three mechanisms working together: passive obstacle avoidance, active obstacle avoidance, and emergency obstacle avoidance. Passive obstacle avoidance utilizes mechanical structures to adapt to changes in the wall contour in real time, while active obstacle avoidance utilizes sensors and servo drives to actively compensate for distance changes. Emergency obstacle avoidance serves as a protective measure, triggering active retraction when contact pressure is abnormal.

[0070] It should be noted that the control methods used in the active obstacle avoidance distance servo control, the start-stop timing control of the multi-nozzle array module 4, the judgment and response of collision signals, the periodic or blockage trigger control of the cleaning pump 62, and the adjustment of the heating film power in the temperature and humidity control component, as well as the specific selection of components such as the sensor voice coil motor 321, the cleaning pump 62, and the heating film, are all existing mature technologies in the field. The setting of relevant parameters can be implemented with reference to existing related technologies, so they are not described in detail here.

[0071] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that an article or device comprising a list of elements includes not only those elements but also other elements not expressly listed. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device comprising said element. Terms such as "connected" or "linked" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect. The orientations or positional relationships indicated by terms such as "upper," "lower," "left," and "right" are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0072] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. An inkjet head, characterized by, include: Nozzle body, distance detection component, pose adjustment component, and multi-nozzle array module; The printhead body includes an outer shell, an inkjet control unit disposed inside the outer shell, and multiple ink channels, which are respectively connected to an external ink supply pipeline to form an ink supply channel; a nozzle plate is provided at the front end of the outer shell, and a plurality of spray holes are formed on the nozzle plate in a matrix arrangement; The multi-orifice array module is integrated on the nozzle plate and includes at least three orifice sub-units. The ink flowing in the multiple ink supply channels is of different colors. Each orifice sub-unit corresponds to an ink supply channel of a different color, and the corresponding ink supply channel is connected to the plurality of orifices through the orifice sub-unit. The distance detection component includes multiple first distance sensors and second distance sensors. The multiple first distance sensors are disposed around the nozzle plate to detect the tilt angle value of the nozzle plate relative to the target wall. The second distance sensors are disposed on the central axis of the nozzle body, and the detection direction of the second distance sensors coincides with the normal direction of the nozzle plate to detect the normal distance value between the nozzle plate and the target wall. The pose adjustment component includes a pose follower mechanism and a distance servo mechanism. The pose follower mechanism includes a movable part, a fixed part, and a two-dimensional rotation platform. The fixed part is connected to an external input end. The two-dimensional rotation platform is located between the movable part and the fixed part. The movable part is supported on the fixed part by the two-dimensional rotation platform, and the movable part has pitch and roll degrees of freedom relative to the fixed part. The distance servo mechanism is fixed on the movable part. The driving end of the distance servo mechanism extends along the normal direction of the nozzle plate and is fixedly connected to the rear end of the nozzle body. The driving end can extend and retract along the normal direction of the nozzle plate to adjust the distance between the nozzle plate and the target wall to achieve active obstacle avoidance. When the front end of the nozzle body contacts the target wall, the movable part drives the distance servo mechanism and the nozzle body to deflect to achieve passive obstacle avoidance.

2. The inkjet head according to claim 1, wherein The nozzle body has an installation interface at its rear end, and the installation interface is fixedly connected to the drive end of the distance servo mechanism. The mounting interface includes a positioning keyway and a positioning pin hole. A sealing ring groove is provided on the mating surface of the mounting interface, and a sealing ring is embedded in the sealing ring groove.

3. The inkjet head according to claim 1, wherein The two-dimensional rotating platform includes a first pivot axis, a second pivot axis, and an intermediate support. The first pivot axis and the second pivot axis are arranged alternately, and the two ends of the first pivot axis are respectively supported on the fixed part and the intermediate support, so that the intermediate support can roll relative to the fixed part. The two ends of the second pivot shaft are respectively supported on the intermediate support and the movable part, so that the movable part can pitch relative to the intermediate support; Springs are connected to the first pivot shaft and the second pivot shaft respectively. The first movable end of the spring is connected to the fixed part or the movable part, and the second movable end is connected to the first pivot shaft or the second pivot shaft.

4. The inkjet head of claim 2, wherein The first distance sensor is an infrared ranging sensor, and at least four infrared ranging sensors are provided, which are respectively arranged at the four corners of the nozzle plate; The detection direction of each infrared ranging sensor is at a 30° angle to the normal direction of the nozzle plate, and is used to detect the tilt angle value of the nozzle plate relative to the target wall. The second distance sensor is an infrared ranging sensor, used to detect the normal distance between the nozzle plate and the target wall. The printing head also includes a control unit. Multiple first distance sensors and second distance sensors are electrically connected to the control unit. The control unit is electrically connected to the distance servo mechanism and is used to control the extension and retraction of the drive end of the distance servo mechanism according to the tilt angle value and the normal distance value, so as to adjust the distance between the nozzle plate and the target wall to achieve active obstacle avoidance.

5. The inkjet head of claim 1, wherein The multi-orifice array module has at least three orifice sub-units arranged sequentially, namely a cyan orifice sub-unit, a magenta orifice sub-unit, and a yellow orifice sub-unit; the cyan orifice sub-unit is located in the middle position, and the magenta and yellow orifice sub-units are symmetrically arranged on both sides of the cyan orifice sub-unit; Among them, at least three of the nozzle sub-units are configured such that, during the reciprocating motion of the printing head, the start-up, stop, and timing of each nozzle sub-unit are independently controlled.

6. The inkjet head of claim 4, wherein The print head also includes an anti-collision protection component; the anti-collision protection component includes a protective sleeve and a pressure sensing band; The protective sleeve is fitted around the outer periphery of the nozzle plate, and a reserved gap is provided between the inner wall of the protective sleeve and the outer edge of the nozzle plate; the protective sleeve is made of silicone material and at least partially protrudes from the front end of the nozzle plate, so that the protective sleeve contacts the target wall surface before the front end of the nozzle plate; The pressure sensing strip is attached to the inner wall of the protective sleeve. The pressure sensing strip is electrically connected to the control unit. The pressure sensing strip is a piezoresistive thin-film sensor used to acquire pressure signals. When the protective sleeve comes into contact with the target wall, the movable part passively deflects around the two-dimensional rotating platform, driving the distance servo mechanism and the nozzle body to rotate in accordance with the contour of the target wall to achieve passive obstacle avoidance; The control unit is used to compare the pressure signal with a preset pressure threshold. When the pressure signal exceeds the preset pressure threshold, it determines that a collision has occurred and obtains a collision signal. The control unit is also used to control the drive end to extend and retract along the normal direction of the nozzle plate according to the collision signal, so as to adjust the distance between the nozzle plate and the target wall to achieve emergency obstacle avoidance.

7. The inkjet head according to claim 6, wherein The distance servo mechanism includes a voice coil motor, the stator of which is fixed on the movable part, and the mover of which serves as the driving end of the distance servo mechanism and is connected to the mounting interface of the nozzle body. The voice coil motor responds to the collision signal from the control unit, driving the nozzle body to retract in a direction away from the target wall to achieve emergency obstacle avoidance.

8. The inkjet head of claim 1, wherein The print head also includes a cleaning assembly; the cleaning assembly includes a cleaning fluid storage tank located on the side of the print head body, a cleaning pump connected to the storage tank, and a cleaning nozzle; The degree of blockage of the nozzle is determined based on the spray response time of the nozzle. When the spray response time exceeds a preset normal value, it is determined that the nozzle is blocked. The cleaning pump is configured to start when a preset condition is met, and spray the cleaning liquid in the cleaning liquid storage tank onto the surface of the nozzle through the cleaning nozzle. The preset conditions include reaching a preset cleaning cycle or the nozzle becoming clogged.

9. The inkjet head of claim 1, wherein The printhead also includes a temperature and humidity control component, which includes a heat insulation layer covering the outer wall of the printhead body, a heating film attached to the outside of the ink channel, a temperature sensor and a humidity sensor disposed inside the printhead body, and a temperature control module electrically connected to the temperature sensor and the humidity sensor respectively. The temperature sensor is used to detect the temperature inside the printhead body to obtain a temperature detection value, and the temperature control module is used to adjust the heating power of the heating film according to the temperature detection value to adjust the ink temperature in the ink cavity. The humidity sensor is used to detect the relative humidity inside the nozzle body to obtain a humidity detection value. The temperature control module is also used to increase the heating power of the heating film according to the humidity detection value, so as to reduce the relative humidity inside the nozzle body.

10. A wall painting equipment, characterized in that, Includes a rack assembly, a drive system, a main control system, and a printhead as described in any one of claims 1 to 9; The frame assembly includes a horizontal guide rail, a vertical guide rail, and a movable slider. The vertical guide rail is disposed on the horizontal guide rail and can slide horizontally along the horizontal guide rail. The movable slider is disposed on the vertical guide rail and can slide along the vertical guide rail. The movable slider serves as an external input end, and the inkjet head is mounted on the movable slider via the fixing part of the posture follow-up mechanism; The drive system includes a horizontal drive motor, a vertical drive motor, a horizontal transmission mechanism, and a vertical transmission mechanism; the horizontal drive motor drives the vertical guide rail to slide along the horizontal guide rail through the horizontal transmission mechanism; the vertical drive motor drives the movable slider and the inkjet head to slide along the vertical guide rail through the vertical transmission mechanism. The main control system includes an image processing unit and a printing control unit. The image processing unit is used to perform color separation, ink volume calculation and printing timing arrangement on the input bitmap image to obtain a printing data file. The printing control unit is used to generate drive signals for each nozzle sub-unit according to the printing data file and transmit them to the printing head.

Images