Vehicle projection curtain device, control method and vehicle

Abstract

The invention relates to the technical field of vehicle projection, in particular to a vehicle projection curtain device, a control method and a vehicle thereof. A vehicle projection curtain device comprises a box body, a reel pipe, a curtain and a clutch, the reel pipe is installed in the box body, and the curtain is wound in the reel pipe; the clutch comprises a brake disc, a base, a friction disc, an elastic piece and an electromagnet, the brake disc is fixed to the reel pipe, the base is installed on the box body, the friction disc is provided with a friction end and a matching end which are oppositely arranged in the axis direction of the reel pipe, the friction end is used for being matched with the brake disc, and the matching end is arranged to be a magnetic end and used for being matched with the electromagnet; one end of the elastic piece is limited to the friction end, and the other end of the elastic piece is limited to the base. The control method is realized based on the vehicle projection curtain device. A vehicle includes a vehicle projection curtain device. According to the clutch, the starting and stopping noise of the clutch can be reduced, and the vehicle using experience is effectively improved.

Description

Technical Field

[0001] This application relates to the field of vehicle projection technology, and in particular to a vehicle projection screen device, control method and vehicle thereof. Background Technology

[0002] The projection screen in a vehicle is one of the core components of the in-vehicle entertainment system, primarily used to enhance the in-vehicle viewing experience. When using the projection screen inside the vehicle, and when the screen is fully open, fully closed, or hovering, the screen roller needs to be braked to maintain its tension.

[0003] Current methods for braking hoses typically involve using an additional motor and gearbox, but the excessive noise from the motor negatively impacts the user experience. Summary of the Invention

[0004] Therefore, it is necessary to provide a vehicle projection screen device, control method, and vehicle that can achieve steady-state braking of the reel and reduce or eliminate noise.

[0005] To solve the above-mentioned technical problems, this application provides the following technical solution:

[0006] A vehicle projection screen device includes a housing, a roller tube, a screen, and a clutch. The roller tube is installed in the housing, and the screen is wound up in the roller tube. The clutch includes a brake disc, a base, a friction disc, an elastic element, and an electromagnet. The brake disc is fixed to the roller tube, and the base is installed in the housing. The friction disc has a friction end and a mating end arranged opposite to each other along the axial direction of the roller tube. The friction end is used to engage with the brake disc, and the mating end is configured as a magnetic end and is used to engage with the electromagnet. The elastic element is positioned on the base in a compressed manner, with one end of the elastic element limited to the friction end and the other end limited to the base.

[0007] The electromagnet is mounted on the base and is energized. The electromagnet and the magnetic end are arranged with the same polarity and repulsion. The force F1 exerted by the elastic element on the friction disk is opposite in direction to the force F2 exerted between the electromagnet and the magnetic end.

[0008] In one embodiment, as the voltage of the electromagnet is gradually reduced, a negative feedback mechanical system is formed between F2 and F1 as the friction disc moves toward the brake disc a certain distance.

[0009] In one embodiment, a second mounting hole is provided through the base in the axial direction of the tube; the friction disc includes a rod, a first disc, and a second disc, the rod is mounted in the second mounting hole, the first disc is disposed at the end of the rod facing the brake disc and spaced apart from the brake disc to form the friction end, and the second disc is disposed at the end of the rod away from the brake disc to form the mating end.

[0010] In one embodiment, the friction end and / or the rod body are made of a non-magnetic material.

[0011] In one embodiment, one or more surfaces of the friction end, the electromagnet, and the brake disc are covered with a damping layer.

[0012] In one embodiment, the clutch further includes a sliding sleeve that is fitted onto the base and rotatably connected to the reel.

[0013] In one embodiment, the vehicle projection screen device further includes a transmission mechanism, through which the clutch and the roller are connected.

[0014] In one embodiment, the transmission mechanism includes a gearbox and a coupling. The gearbox has an output shaft and an input shaft. The output shaft is fixedly connected to the brake disc, and the input shaft is connected to the reel via the coupling.

[0015] In one embodiment, the vehicle projection screen device further includes a take-up member, which is housed in the housing and wound around the tube; wherein one end of the take-up member is fixed to the housing and the other end is fixed to the tube.

[0016] In one embodiment, the screen has a fixed end and a hanging end, the fixed end being connected to the roller tube, and the hanging end being able to extend or retract from the housing; the vehicle projection screen device further includes an arm mechanism, the arm mechanism being mounted on the housing and connected to the hanging end, and the arm mechanism having a folded state and an unfolded state, the arm mechanism being able to fold into the housing or unfold out of the housing when switching between the folded state and the unfolded state, so as to drive the hanging end to move in the lifting direction of the screen.

[0017] This application also provides the following technical solutions:

[0018] A control method, implemented based on the vehicle projection screen device, the control method comprising:

[0019] During the movement of the friction disc toward the brake disc, the voltage U of the electromagnet at the current time t0 when it is energized is obtained, and the voltage U is greater than or equal to U1; where U1 is set as the maximum voltage applied to the electromagnet when F1 equals F2.

[0020] The voltage U is gradually reduced by a preset amplitude threshold until the voltage U is zero.

[0021] In one embodiment, the step of gradually reducing the voltage U by a preset amplitude threshold until the voltage U is zero includes:

[0022] The voltage U is gradually reduced to U1 by a first preset amplitude threshold, so that F1 equals F2;

[0023] The voltage U1 is gradually reduced to U2 by the second preset amplitude threshold. When the voltage is U2, the elastic element gradually resets and F1 increases while F2 decreases and reaches a balance. When the voltage is U2, the friction disc begins to contact the brake disc.

[0024] As U2 continues to decrease gradually with the third preset amplitude threshold until it reaches zero, under the action of the elastic element, the friction disc squeezes the brake disc and forms a friction fit.

[0025] This application also provides the following technical solutions:

[0026] A vehicle includes a body and a vehicle projection screen device, the vehicle projection screen device being mounted on the body.

[0027] Compared to existing technologies, the vehicle projection screen device and its vehicle utilize a clutch to achieve braking and unlocking between the winding tube and the transmission mechanism, reducing noise during "steady-state" operation and lowering costs. Simultaneously, by incorporating an electromagnet, friction end, and elastic element, and with the electromagnet and magnetic end arranged in a repulsive configuration when energized, and with F2's direction opposite to F1's, as the friction disc approaches the brake disc, the change (increase) in the distance S results in F1 increasing exponentially or multiples, while F2 gradually decreases. Furthermore, the traction effect of F1 on F2 causes F1-F2 to increase with the increase in distance S, meaning the resultant force of F2-F1 limits further increases in distance S, minimizing impact energy and allowing the friction disc to gradually approach the brake disc, finally contacting it at near-zero speed. This eliminates the impact noise between the friction disc and the brake disc, thereby reducing clutch "start-stop" noise and effectively improving the user experience. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A front view structural diagram of the vehicle projection screen device provided in this application.

[0030] Figure 2 Provided for this application Figure 1 Sectional view at point AA.

[0031] Figure 3 Provided for this application Figure 2 A magnified view of a section of the middle box.

[0032] Figure 4 Provided for this application Figure 2 Sectional view of the clutch position in the middle BB.

[0033] Figure 5 Provided for this application Figure 2 Cross-sectional view of the BB and roll receiving position.

[0034] Figure 6 Provided for this application Figure 4 Sectional view at point CC.

[0035] Figure 7 Provided for this application Figure 5 Sectional view at point DD.

[0036] Figure 8 This is a side view of the clutch structure provided in this application.

[0037] Figure 9 Provided for this application Figure 8 Sectional view at EE.

[0038] Figure 10 Provided for this application Figure 9 A magnified view of the central base area.

[0039] Figure 11 A diagram showing the relationship between the elastic element, the electromagnet, and the change in S-pitch in the related technology provided in this application.

[0040] Figure 12 A diagram showing the relationship between the elastic element, the electromagnet, and the change in S-pitch provided in this application.

[0041] Figure 13A flowchart of the control method provided in this application.

[0042] The component labels are as follows:

[0043] 100. Vehicle projection screen device; 10. Housing; 11. Cover; 12. Base; 121. Crossbeam; 122. Adapter arm; 13. Receiving cavity; 20. Roller tube; 30. Screen; 31. Fixed end; 32. Suspension end; 40. Transmission mechanism; 41. Gearbox; 411. Output shaft; 412. Input shaft; 413. Limiting plate; 414. Support column; 42. Coupling; 43. Roller clip; 50. Clutch; 51. Brake disc; 52. Base; 521. 522. Mounting hole 1; 523. Mounting hole 3; 53. Friction disc; 531. Friction end; 532. Mating end; 533. Rod body; 534. First disc body; 535. Second disc body; 54. Elastic element; 55. Electromagnet; 56. Sliding sleeve; 60. Retractor; 61. Reel; 62. Support; 63. Coil spring; 70. Arm mechanism; 71. Arm motor; 72. Arm; 721. First rod; 722. Second rod; 200. Control method. Detailed Implementation

[0044] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0045] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0048] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0049] Please see Figures 1 to 10 This application provides a vehicle projection screen device 100, which is installed on the vehicle body for in-vehicle entertainment and to enhance the viewing experience.

[0050] Specifically, please refer to Figures 1 to 4 The vehicle projection screen device 100 includes a housing 10, a roller tube 20, a screen 30, and a clutch 50. The housing 10 is used for mounting on the vehicle body. The roller tube 20 is installed inside the housing 10, and the screen 30 is wound up within the roller tube 20. The clutch 50 is located inside the housing 10 and connected to the roller tube 20. Here, the clutch 50 is an electronic clutch, which mainly functions to engage and disengage, thereby unlocking and locking the roller tube 20. It should be explained that when the clutch 50 is de-energized, the clutch is in the "engaged" state, and the roller tube 20 is in the locked state, meaning the roller tube 20 is locked and does not rewind the screen 30. When the clutch 50 is energized, the clutch is in the "disengaged" state, and the roller tube 20 is in the unlocked state, meaning the roller tube 20 is in a free state and can raise or release the screen 30.

[0051] In one embodiment, such as Figure 3 As shown, the box body 10 includes a cover 11 and a seat 12. The seat 12 is used to fix it to the vehicle body. The cover 11 is installed on the seat 12 and forms a receiving cavity 13 with the seat 12. The reel 20 is rotatably installed in the receiving cavity 13.

[0052] Furthermore, such as Figure 3 and Figure 4As shown, the seat 12 includes adapter arms 122 and a crossbeam 121. There are generally two adapter arms 122. In the width direction of the vehicle, one adapter arm 122 is installed on the left side of the vehicle body, and the other adapter arm 122 is installed on the right side, thus forming a symmetrical support structure. This structure can stably fix the entire box 10 to the vehicle body, preventing displacement or shaking of the box 10 during vehicle movement (such as bumps or turns), and ensuring stability when the curtain is unfolded and rolled up. The crossbeam 121 is mounted on the two adapter arms 122, and the cover 11 is placed on the crossbeam 121, forming a receiving cavity 13. The clutch 50 is fixed to the crossbeam 121. Here, the crossbeam 121 is mounted on the two adapter arms 122, forming a load-bearing structure spanning the width of the vehicle, providing both a mounting base for the cover 11 and fixing the clutch. This provides a stable installation environment for the clutch 50, preventing vibration and displacement during clutch operation.

[0053] In one embodiment, please refer to Figure 5 and Figure 7 The vehicle projection screen device 100 also includes a winding member 60, which is housed in the housing 10 and wound around the winding tube 20; wherein, one end of the winding member 60 is fixed to the housing 10 and the other end is fixed to the winding tube 20, and the winding member 60 is used for winding up the screen 30.

[0054] Specifically, the end of the take-up piece 60 away from the reel tube 20 is fixed to the crossbeam 121.

[0055] Optionally, the winding component 60 can be configured as a coil spring or a seat belt retractor, which can enable the automatic winding of the curtain 30.

[0056] Preferably, the winding member 60 is configured as a coil spring. The winding force provided by the coil spring can provide tension during the suspension of the curtain 30, thereby keeping the curtain 30 in a taut state and providing the curtain 30 with shock resistance.

[0057] In one embodiment, please refer to Figure 5The winding component 60 includes a roller 61, a support 62, and a coil spring 63. One end of the roller 61 is circumferentially limited to the winding tube 20, and the other end is connected to and rotatably connected to the support 62. The support 62 is fixed to the housing 10, specifically to the crossbeam 121. One end of the coil spring 63 is limited to the roller 61, and the other end is limited to the support 62. The coil spring 63 is wound around the roller 61. When the curtain 30 is unfolded, the coil spring 63 is in a stretched or unfolded state. When the curtain 30 needs to be wound up, the clutch 50 unlocks the winding tube 20, allowing the winding tube 20 to be in a free state. Under the retraction force of the coil spring 63, the winding tube 20 rotates and winds up the curtain 30. Meanwhile, when the curtain 30 is suspended at a certain position (for example, when the curtain 30 is fully open or fully closed, 30% unfolded, 50% unfolded, etc.), the coil spring 63 will cause the curtain 30 to tend to fold back, thereby keeping the curtain 30 in a taut state so that the curtain 30 has better shock resistance.

[0058] Please continue reading 1 and... Figure 2 The vehicle projection screen device 100 also includes an arm mechanism 70. The screen 30 has a fixed end 31 and a suspended end 32 (i.e., a free end or a movable end). The fixed end 31 is connected to the roll tube 20, and the suspended end 32 can extend or retract into the housing 10. The arm mechanism 70 is mounted on the housing 10 and connected to the suspended end 32. The arm mechanism 70 has an unfolded state and a folded state. When switching between the unfolded and folded states, the arm mechanism 70 can be folded inside the housing 10 or unfolded outside the housing 10, and it drives the suspended end 32 to move in the lifting direction of the screen 30. At the same time, when the arm mechanism 70 unfolds, the roll-up component 60 unfolds, and the screen 30 descends. When the arm mechanism 70 folds, the roll-up component 60 automatically resets, thereby automatically folding the screen 30, at which time the screen 30 rises.

[0059] Furthermore, the number of boom mechanisms 70 is set to two, and the two boom mechanisms 70 are spaced apart in the axial direction of the roll tube 20 (i.e., generally the width direction of the vehicle). The boom mechanisms 70 are respectively connected to the two sides of the suspension end 32 in the width direction of the vehicle. In this way, the curtain 30 is more stable when it rises or falls.

[0060] Please continue reading 1 and... Figure 2The arm mechanism 70 includes an arm motor 71 and an arm 72. The arm motor 71 is installed inside the housing 10. One end of the arm 72 is connected to the arm motor 71, and the other end is connected to the suspension end 32. Driven by the arm motor 71, the arm 72 can be folded inside the housing 10 or unfolded outside the housing 10. Here, by setting up the arm motor 71 and the arm 72, the arm motor 71 drives the folding and unfolding of the arm 72, thereby enabling the screen 30 to be infinitely suspended (at any position) by utilizing the self-locking of the arm motor 71. In addition, after the winding component 60 winds up the screen 30, the self-locking of the arm motor 71 can make the screen 30 present a better tension, which is more conducive to the shock resistance of the screen 30.

[0061] Specifically, the arm 72 includes a first rod 721 and a second rod 722 that are hinged together. The end of the first rod 721 away from the second rod 722 is hinged to the housing 10 and connected to the arm motor 71. The end of the second rod 722 away from the first rod 721 is hinged to the hanging end 32 of the curtain 30. The arm motor 71 can rotate the first rod 721 clockwise or counterclockwise, or brake the first rod 721, thereby realizing actions such as folding, unfolding, or keeping the first rod 721 and the second rod 722 in a suspended position.

[0062] In this embodiment, with Figure 1 Taking this as an example, we will explain in detail how the arm mechanism 70, clutch 50 and retractor 60 cooperate to achieve the raising and lowering of the curtain.

[0063] When the curtain 30 rises, the clutch 50 is energized and in the "disengaged" state. At this time, the arm motor 71 drives the first arm 721 to rotate counterclockwise around point O. a Rotate to R b At that time, the curtain 30 from S a Position raised to S b Position. When the curtain 30 descends, the clutch 50 is energized and in the "disengaged" state. At this time, the arm motor 71 drives the first arm 721 to rotate clockwise around point O. When R... b Rotate to R a At that time, the curtain 30 from S b Position drops to S a Location.

[0064] When the curtain 30 is suspended, fully open, or fully closed and taut, the clutch 50 is de-energized and in the "engaged" state. At this time, the arm motor 71 drives the first rod 721 to rotate clockwise around point O, the position of the curtain 30 remains unchanged, and the tension increases.

[0065] In one embodiment, the vehicle projection screen device 100 further includes a controller (not shown), which is electrically connected to the boom motor 71 and the clutch 50. Thus, by centrally controlling the operating status of the boom motor 71 and the clutch 50 through the controller, the user experience is further enhanced.

[0066] Please see Figure 4 , Figure 6 , Figures 8 to 10 The clutch 50 includes a brake disc 51, a base 52, a friction disc 53, an elastic element 54, and an electromagnet 55. The brake disc 51 is fixed to the reel 20, and the base 52 is mounted on the housing 10. The friction disc 53 has a friction end 531 and a mating end 532 arranged opposite to each other in the axial direction of the reel 20. The friction end 531 is used to mate with the brake disc 51, and the mating end 532 is set as a magnetic end and is used to mate with the electromagnet 55. The elastic element 54 is installed on the base 52 in a compressed manner. One end of the elastic element 54 is limited to the friction end 531, and the other end is limited to the base 52. The electromagnet 55 is installed on the base 52 and, in the energized state, the electromagnet 55 and the magnetic end (matting end 532) are arranged with the same polarity and repulsion. The force F1 exerted by the elastic element 54 on the friction disc 53 is opposite in direction to the force F2 exerted by the electromagnet 55 on the magnetic end. In other words, the force between the electromagnet 55 and the magnetic end (fitting end 532) is F1, and the force exerted by the elastic element 54 on the friction disc 53 is F2, with the direction of F2 being opposite to that of F1. Thus, the force exerted by the electromagnet 55 on the friction disc 53 is suppressed, causing the friction disc 53 to move further toward the brake disc 51, thereby reducing the speed at which the friction disc 53 impacts the brake disc 51 and reducing the noise during engagement between the friction disc 53 and the brake disc 51, i.e., reducing the "clutch noise".

[0067] In one embodiment, as the friction disc 53 gradually moves towards the brake disc 51, the electromagnet 55 is de-energized by gradually reducing the voltage. That is, as the clutch 50 switches from the "disengaged" state to the "engaged" state, the voltage of the electromagnet 55 gradually decreases until it reaches zero. It can be understood that as the voltage of the electromagnet 55 gradually decreases, the force exerted by the electromagnet 55 gradually decreases, and during this process, the elastic force of the elastic element 54 also decreases. Therefore, during the switch from the "disengaged" state to the "engaged" state, the force generated by the electromagnet 55 continuously inhibits the movement of the friction disc 53. F1 and F2 will mutually restrain each other, thereby preventing the friction disc 53 from instantly colliding with the brake disc 51 under the elastic force of the elastic element 54, thus further reducing impact noise and improving the driving experience.

[0068] Specifically, the base 52 has a first mounting hole 521, which extends along the axis of the coil 20. One end of the elastic member 54 extends into the first mounting hole 521 and is limited to the wall of the first mounting hole 521, while the other end is limited to the friction end 531.

[0069] Please refer to [link / reference needed] for further explanation. Figure 11 In the related technology, the electromagnetic force F1=K after the electromagnet 55 is energized. 电磁体 (S+R 0电磁体 ) N , where K 电磁体 R represents the magnetic flux density of electromagnet 55, N represents the magnetic field index of electromagnet 55, and R represents the magnetic flux density of electromagnet 55. 0电磁体 This represents the near-range correction parameter of electromagnet 55. The force provided by elastic element 54 is F2=F 初始位置 +K1S, where K1 represents the elastic coefficient of the elastic element 54, and S represents the distance the friction disc 53 moves in the axial direction of the winding tube 20. It is understandable that, in the existing technology, the brake motor is eliminated, and the clutch 50 is used to brake the winding tube 20, thus eliminating the noise caused by motor braking. However, when the electromagnet 55 is momentarily de-energized, F1=0, F2-F1>0, and this force (F2) drives the friction disc 53 to collide with the brake disc 51, and the impact energy... This refers to the area enclosed by the BCDF curves, where the impact sound (i.e., clutch sound) will occur. Here, the total stroke S of the friction disc 53 is preset to be 1mm, which is the upper limit of integration.

[0070] Furthermore, the relationship between the elastic element, the electromagnet, and the change in S-distance is plotted, as shown in Table 1 and... Figure 11 As shown.

[0071] Please see Figure 11 And combining with Table 1, as the voltage of electromagnet 55 is gradually reduced, the curve gradually declines from AE to BG (F 电磁体 Within a certain range, the force (proportional to the square of the voltage) is applied. When F2-F1>0, this force (F2-F1) drives the friction disc 53 to collide with the brake disc 51, and the impact energy... This refers to the area enclosed by the BGF curve. It's understandable that although gradually reducing the voltage of electromagnet 55 reduces the impact energy compared to instantaneous power outage, once the voltage of electromagnet 55 exceeds the critical voltage, i.e., the corresponding critical point (B), F2-F1 increases rapidly with increasing spacing S. This means that a positive feedback system is formed between F2 and F1 at this point, and a positive feedback system implies that impact is unavoidable even with the gradually decreasing voltage control method.

[0072] Table 1

[0073]

[0074] It should be noted that, in Figure 11 In the graph, the horizontal axis represents the change in distance S (from 0 to 1 mm), and the vertical axis represents the change in magnetic force after the electromagnet 55 is energized; that is, the vertical axis represents magnetic force. The blue line AE (electromagnet 14V) and the gray line BG (electromagnet 9.5V) are the attraction curves of the electromagnet, and the orange line BF is the curve of the elastic force of the elastic element changing with the distance S. When the voltage of the electromagnet is reduced, the attraction curve of the electromagnet will gradually change from the "blue AE line at 14V" to the "gray BG line at a lower voltage (e.g., 9.5V)", that is, as the voltage decreases, the attraction force of the electromagnet decreases, so the curve "sinks" overall. Here, Figure 9 In the diagram, the two voltages "14V" and "9.5V" of the electromagnet are used to demonstrate the change in the electromagnet's attractive force under different voltages, representing the process of voltage decreasing from high to low.

[0075] Returning to this application, in conjunction with Figure 12 As shown in Table 2, this application utilizes the engagement / disengagement characteristics of the clutch 50 to achieve braking and unlocking between the reel 20 and the transmission mechanism 40, thereby reducing noise during "steady-state" operation and lowering costs. Furthermore, by configuring an electromagnet 55, a friction end 531, and an elastic element 54, and ensuring that, in the energized state, the electromagnet 55 and the magnetic end (coupling end 532) are arranged with like poles repelling each other, and the direction of F2 is opposite to the direction of F1, as the friction disc 53 approaches the brake disc 51, the voltage of the electromagnet 55 is gradually reduced, increasing the change in the distance S. F1 (electromagnetic force or repulsive force) increases exponentially or multiples, while F2 (elastic force) gradually decreases. Furthermore, the traction effect of F1 on F2 causes F1-F2 to increase as the distance S increases (for example, the value of F1-F2 decreases from -3 to -2, and then further decreases to -1). That is, the resultant force of F2-F1 limits the further increase of S, thus forming a negative feedback mechanical system to further weaken the impact energy as much as possible, so that the friction disc 53 can gradually approach the brake disc 51 and finally contact the brake disc 51 at a speed close to zero, eliminating the impact noise between the friction disc 53 and the brake disc 51, thereby reducing the noise of the clutch 50 "starting and stopping" and effectively improving the driving experience.

[0076] Here, negative feedback mechanics refers to a reverse adjustment mechanism. For example, when a certain state (such as the distance between friction discs) changes, the system generates a force that "prevents this change from continuing to increase," causing the state to stabilize. In other words, the "driving force (F2-F1)" that originally propelled S to increase is weakened, or even becomes a "resistance," limiting S from continuing to increase; that is, the more the state changes, the stronger the force that prevents it from changing becomes, eventually causing the state (distance S) to gradually stabilize.

[0077] It should be noted that, in Figure 12In the diagram, the horizontal axis represents the change in distance S (from 0 to 1 mm), and the vertical axis represents the change in magnetic force after the electromagnet 55 is energized; that is, the vertical axis represents magnetic force. Curve HF represents the force F2 exerted by the elastic element, and curves JH, JK, and FI represent the changes in the attractive force of the electromagnet at different voltages, illustrating the process of voltage decreasing from high to low. Looking at the electromagnet curves, for example, the blue line JH, the green dotted line JK, and the gray line FI represent F1 at different voltages, used to illustrate the change in the attractive force of the electromagnet under different voltages, representing the process of voltage decreasing from high to low.

[0078] Please see Figure 8 and Figure 9 The transmission mechanism 40 includes a reduction gearbox 41 and a coupling 42. The reduction gearbox 41 has an output shaft 411 and an input shaft 412. The output shaft 411 is fixedly connected to the brake disc 51, and the input shaft 412 is connected to the winding tube 20 via the coupling 42. In this way, the reduction gearbox 41 can increase the torque of the winding tube 20 by adjusting its rotational speed and decreasing the torque, so that the brake disc 51 can brake the winding tube 20 with less friction. Meanwhile, the coupling 42 ensures smooth torque transmission and absorbs coaxiality tolerances.

[0079] Here, the reduction gearbox 41 can be configured as a gear reducer, a worm gear reducer, a cycloidal pinwheel reducer, etc. In this embodiment, the reduction gearbox 41 is configured as a gear reducer. The coupling 42 can be configured as a rigid coupling or a flexible coupling, depending on the requirements. In this embodiment, the coupling 42 is configured as a universal coupling.

[0080] like Figure 9 As shown, a limiting piece 413 is provided on the output shaft 411. The limiting piece 413 is positioned and abuts against the housing of the gearbox 41 in the axial direction of the tube 20, thereby restricting the movement of the output shaft 411 in the axial direction of the tube 20.

[0081] Here, two limit plates 413 are configured, one inside the gearbox 41 and the other outside the gearbox 41. Both limit plates 413 are positioned against the housing of the gearbox 41, thus providing a limit on both sides of the tube 20 along the axial direction, thereby improving the reliability of the limit on the output shaft 411.

[0082] In one embodiment, such as Figure 8 As shown, a support column 414 is provided between the reduction gearbox 41 and the clutch 50. One end of the support column 414 is fixed to the reduction gearbox 41, and the other end is fixed to the clutch 50. Thus, a movable space is formed between the clutch 50 and the reduction gearbox 41. The brake disc 51 is located in the movable space, and the friction disc 53 can move toward or away from the brake disc 51 in the movable space.

[0083] Furthermore, such as Figure 8 or Figure 9 As shown, the transmission mechanism 40 also includes a reel clamp 43, which is fixed to the reel tube 20 and connected to the input shaft 412 via a coupling 42. That is, the torque of the coupling 42 is transmitted to the reel tube 20 through the reel clamp 43.

[0084] In one embodiment, a plastic coating or damping layer (not shown) may be added to the outer surface of the brake disc 51. The plastic coating or damping layer helps to reduce the resonance amplitude of the mechanical structure, reduce contact noise, further reduce the noise of the clutch 50 during start-stop, and improve the driving experience.

[0085] Please continue reading. Figure 4 The base 52 mainly serves as a load-bearing component and is fixed to the crossbeam 121. Specifically, the base 52 can be fixed in a detachable manner using screws, bolts, or clips, thus facilitating the disassembly, assembly, and maintenance of the base 52.

[0086] The friction disc 53 mainly works in conjunction with the brake disc 51 to achieve the engagement / disengagement state of the clutch 50. That is, when the friction disc 53 and the brake disc 51 are in frictional engagement, the clutch 50 is in the engaged state; when the friction disc 53 and the brake disc 51 are in frictional disengagement, the clutch 50 is in the disengaged state.

[0087] like Figure 10 As shown, a third mounting hole 523 is provided on the base 52, extending along the axial direction of the coil 20. The electromagnet 55 is located inside the third mounting hole 523, and is spaced apart from the friction disc 53 along the axial direction of the coil 20. This interval can also be referred to as the spacing S.

[0088] In one embodiment, such as Figure 10 As shown, the friction disc 53 includes a rod 533, a first disc 534, and a second disc 535. A second mounting hole 522 is provided through the base 52 in the axial direction of the winding tube 20. The rod 533 is installed in the second mounting hole 522 and can move in the axial direction of the winding tube 20. In the axial direction of the winding tube 20, the first disc 534 is disposed at the end of the rod 533 facing the brake disc 51 and is spaced apart from the brake disc 51 to form a friction end 531. The second disc 535 is disposed at the end of the rod 533 away from the brake disc 51 and forms a mating end 532.

[0089] Furthermore, the friction end 531 and / or the rod 533 are made of non-magnetic materials. For example, the friction end 531 can be made of materials such as aluminum alloy, ceramic, or plastic. Similarly, the rod 533 can also be made of materials such as aluminum alloy, ceramic, or plastic.

[0090] Preferably, the friction end 531 may be coated with plastic or covered with a damping layer (not shown). Such use of plastic coating or damping layer helps to reduce the resonance amplitude of the mechanical structure, reduce contact noise, further reduce the noise of clutch 50 "starting and stopping", and improve the user experience.

[0091] like Figure 6 and Figure 9 As shown, the number of elastic elements 54 is configured as group A, with group A elastic elements 54 spaced circumferentially along the base 52, where A is a natural number and 2≤A≤6. This configuration ensures that the friction disc 53 is subjected to the force of the elastic elements 54 at multiple locations circumferentially around the base 52, thus improving the stability of the friction disc 53 during operation.

[0092] Here, the value of A can be 2, 4, 6, etc. Of course, it is not limited to these; the value of A can also be chosen according to the actual situation. In this embodiment, the value of A is 4.

[0093] Preferably, the elastic elements 54 of group A are evenly spaced around the base 52, so that the elastic elements 54 on the friction disc 53 are more evenly distributed.

[0094] In one implementation, the electromagnet 55 is coated with plastic or encased in a damping layer. This use of plastic coating or damping layer helps reduce the resonance amplitude of the mechanical structure, lowers contact noise, further reduces the noise during the start-stop of the clutch 50, and improves the user experience.

[0095] Please see Figure 4 and 10 The clutch 50 also includes a sliding sleeve 56, which is fitted onto the base 52 and rotatably connected to the coil tube 20, thereby enabling rotation between the coil tube 20 and the base 52.

[0096] Alternatively, the material of the sliding sleeve 56 may be polyoxymethylene (POM), polyamide (PA), polytetrafluoroethylene (PTFE), or a mixture thereof. This configuration allows the sliding sleeve 56 to have a lower coefficient of friction and higher wear resistance.

[0097] Please see Figure 13 This application also provides a control method 200, which is implemented based on the structure of the vehicle projection screen device 100. The steps of the control method 200 include:

[0098] Step S1: During the process of the friction disc 53 gradually moving towards the brake disc 51, the voltage U of the electromagnet 55 at the current time t0 when it is in the energized state is obtained, and the voltage U is greater than or equal to U1; where U1 is set to the maximum voltage connected to the electromagnet 55 when F1 equals F2.

[0099] Step S2: Gradually reduce the voltage U by a preset amplitude threshold until the voltage U is zero.

[0100] Understandably, in this method, when energized, the electromagnet 55 and the magnetic end (coupling end 532) are arranged with like poles repelling each other, and the direction of F2 is opposite to that of F1. Thus, as the voltage of the electromagnet 55 is gradually reduced (even when the friction disc 53 approaches the brake disc 51), as the distance S changes (increases), F1 (electromagnetic force or repulsive force) increases exponentially or multiples, while the elastic element 54 gradually resets, and F2 (elastic force) gradually decreases. Furthermore, the traction effect of F1 on F2 causes F1-F2 to increase with the increase of the distance S, meaning the resultant force of F2-F1 limits further increases in S. This constitutes a negative feedback mechanical system to weaken the impact energy as much as possible, allowing the friction disc 53 to gradually approach the brake disc 51 and finally contact it at near-zero speed, eliminating the impact noise between the friction disc 53 and the brake disc 51, thereby reducing the noise of clutch "start-stop" and effectively improving the driving experience.

[0101] In step S1, as the friction disc 53 gradually moves towards the brake disc 51, that is, during the process of the clutch 50 switching from the "disengaged" state to the "engaged" state, the clutch 50 is in the "disengaged" state before this. That is, the clutch 50 is in the "disengaged" state, that is, the clutch 50 is in a continuously energized state.

[0102] Here, the preset amplitude threshold J can be / 10%U per second, meaning the voltage U decreases by 10%U per second. Of course, the preset amplitude threshold J can also be / 5%U per second, / 8%U per second, / 12%U per second, / 15%U per second, etc., and the specific preset amplitude threshold J can be set according to actual needs. Generally speaking, the smaller the preset amplitude threshold J, the better. However, considering the operation time, the preset amplitude threshold J should not be set too small.

[0103] Further, step S2, "gradually reducing the voltage U by a preset amplitude threshold until the voltage U is zero," includes:

[0104] Step S21: The voltage U is gradually reduced to U1 by a first preset amplitude threshold so that F1 equals F2;

[0105] In step S22, the voltage U1 is gradually reduced to U2 by the second preset amplitude threshold. When the voltage is U2, the elastic element 54 gradually resets and F1 increases while F2 decreases and is in a balanced state. When the voltage is U2, the friction disc 53 begins to contact the brake disc 51.

[0106] In step S23, U2 is gradually reduced to zero by the third preset amplitude threshold. At this time, under the action of the elastic element 54, the friction disc 53 squeezes the brake disc 51 and forms a friction fit.

[0107] Here, the first preset amplitude threshold is denoted as J1, and J1 can be set to / 5%U per second, / 10%U per second, / 15%U per second, etc.

[0108] The second preset amplitude threshold is denoted as J2, which can be set to / 8%U1 per second, / 10%U1 per second, / 15%U1 per second, etc.

[0109] The third preset amplitude threshold is denoted as J3, which can be set to / 2%U2 per second, / 3%U2 per second, / 4%U2 per second, etc.

[0110] Generally, the values ​​of the first preset amplitude threshold J1, the second preset amplitude threshold J2, and the third preset amplitude threshold J3 are different. Voltages U, U1, and U2 are all preset values, and their specific values ​​can be set according to actual needs.

[0111] The working principle of this application is explained in detail below:

[0112] In one specific embodiment, it is first necessary to obtain the mechanical equation of the elastic element 54 as a function of the distance S:

[0113] F 弹性件 =F 弹性件初始 +K 弹性件 S=6-2.2S…………………………………………(1);

[0114] Obtain the mechanical equation for the friction end 531 as a function of the distance S (assuming the mass of the friction disk 53 is m). 摩擦盘 =10 grams, and m 摩擦盘 <<Mass of other parts of clutch 50, "<<" indicates much smaller):

[0115] F 电磁体 =K 电磁体 (1-S+R0) N =73.5(U / U0) 2 (3-S) -2.5 …………………………(2);

[0116] Where U is the adjustable voltage, N represents the magnetic index of electromagnet 55; U0 is the rated voltage, and U0 = 14V, K 电磁体 =73.5, R0=2.

[0117] Let S=0, F 弹性件 = F 电磁体 Therefore, U1 = 15.8V;

[0118] Let S=1, F 弹性件 = F 电磁体 Therefore, U2 = 7.5V.

[0119] Furthermore, based on the above relationships, the relationship between the elastic element 54, the electromagnet 55, and the change in the S-pitch is plotted, as shown in Table 2. Figure 12 As shown.

[0120] Table 2

[0121]

[0122] Through Table 2 and Figure 12 It can be seen that during the power-off process (the friction disc 53 gradually contacts the brake disc 51, i.e., the process of the clutch 50 switching from the "disengaged" state to the "engaged" state), before time t0, the clutch 50 is in a continuously energized state and the voltage U≥U1. The voltage is gradually reduced, and when the voltage = U1, S0=0, F... 弹性件 = F 电磁体 =6N, friction disc 53 begins to move towards brake disc 51, F 电磁体 It will increase exponentially or multiple times as the spacing S increases, while F 弹性件 As the distance S gradually decreases, this application constructs a negative feedback mechanical system, meaning that as the distance S increases, F will... 电磁体 With F 弹性件 The resultant force limits the further spontaneous increase of the spacing S, thus reaching equilibrium until the voltage is further reduced. As the voltage continues to decrease, the HJ curve gradually descends to the KL curve, and the spacing S continues to increase (to the Z-axis). Figure 12 As shown), when voltage = U2, S1 = 1mm, F 弹性件 = F 电磁体 =3.8N, the friction end 531 of the friction disc 53 begins to contact the brake disc 51 (pressure = 0). Continue to reduce the voltage, but keep the gap S unchanged. When the voltage = 0, S2 = 1mm, F 弹性件 =3.8N, F 电磁体 =0, friction disc 53 presses brake disc 51 with a pressure of 3.8N.

[0123] During the energizing process (the friction disc 53 gradually disengages from the brake disc 51, i.e., the clutch 50 switches from the "engaged" state to the "disengaged" state), before time t'0, the clutch is in an on / off state with voltage = 0. The voltage is gradually increased, and when the voltage = U2, S'0 = 1, F... 弹性件 =F 电磁体 =3.8N, the friction disk 53 begins to move towards the electromagnet 55, at which point the distance S gradually decreases, F 电磁体 It will decrease exponentially or by a multiple as the spacing S decreases, while F 弹性件 As the spacing S gradually increases, this application constructs a negative feedback mechanical system, that is, a decrease in spacing S will lead to F 电磁体 With F 弹性件 The resultant force restricts S from further spontaneously decreasing, thus reaching equilibrium until the voltage U is further increased. As the voltage continues to increase, the IF curve gradually rises to the KL curve, and the spacing S continues to decrease (to the Z-point abscissa). Figure 12 As shown), when voltage = U1, S'1 = 0 mm, F 弹性件 = F 电磁体 =6N, the friction end 531 of the friction disk 53 begins to contact the electromagnet 55 (pressure = 0). Continue to appropriately increase the voltage ≥ U1, but keep the gap S unchanged, S'2 = 0mm, F 弹性件 =6N, F 电磁体 ≥6N, the friction disc 53 presses the electromagnet 55 or the base 52 with a pressure of ≥0N.

[0124] It should be noted that S0, S1, , This represents the spacing value at a specific location; S is a variable of spacing, for example, when the power is off, S will increase from 0 to 1mm, and when the power is on, S will decrease from 1mm to 0.

[0125] This application also provides a vehicle, including a vehicle body and a vehicle projection screen device 100, the vehicle projection screen device 100 being mounted on the vehicle body.

[0126] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A vehicle projection screen device, characterized in that, It includes a housing (10), a roller (20), a curtain (30), and a clutch (50). The roller (20) is installed inside the housing (10), and the curtain (30) is rolled up in the roller (20). The clutch (50) includes a brake disc (51), a base (52), a friction disc (53), an elastic element (54), and an electromagnet (55). The brake disc (51) is fixed to the reel (20), and the base (52) is mounted on the housing (10). The friction disc (53) has a friction end (531) and a mating end (532) arranged opposite to each other in the axial direction of the reel (20). The friction end (531) is used to mate with the brake disc (51), and the mating end (532) is set as a magnetic end and is used to mate with the electromagnet (55). The elastic element (54) is installed on the base (52) in a compressed manner, and one end of the elastic element (54) is limited to the friction end (531), and the other end is limited to the base (52). The electromagnet (55) is mounted on the base (52) and in the energized state, the electromagnet (55) and the magnetic end are arranged with the same polarity repulsing each other, and the force F1 exerted by the elastic element (54) on the friction disk (53) is opposite in direction to the force F2 exerted between the electromagnet (55) and the magnetic end.

2. The vehicle projection screen device according to claim 1, characterized in that, As the voltage of the electromagnet (55) is gradually reduced, a negative feedback mechanical system is formed between F2 and F1 as the friction disc (53) moves toward the brake disc (51).

3. The vehicle projection screen device according to claim 1 or 2, characterized in that, In the axial direction of the tube (20), the base (52) has a through-hole (522). The friction disc (53) includes a rod (533), a first disc (534), and a second disc (535). The rod (533) is installed in the second mounting hole (522). In the axial direction of the coil tube (20), the first disc (534) is disposed at one end of the rod (533) facing the brake disc (51) and is spaced apart from the brake disc (51) to form the friction end (531). The second disc (535) is disposed at one end of the rod (533) away from the brake disc (51) and forms the mating end (532).

4. The vehicle projection screen device according to claim 3, characterized in that, The friction end (531) and / or the rod (533) are made of non-magnetic material.

5. The vehicle projection screen device according to claim 1, characterized in that, One or more surfaces of the friction end (531), the electromagnet (55), and the brake disc (51) are covered with a damping layer.

6. The vehicle projection screen device according to claim 1, characterized in that, The clutch (50) also includes a sliding sleeve (56), which is sleeved on the base (52) and rotatably connected to the coil (20).

7. The vehicle projection screen device according to claim 1, characterized in that, The vehicle projection screen device also includes a transmission mechanism (40), and the clutch (50) and the roller tube (20) are connected by transmission mechanism (40).

8. The vehicle projection screen device according to claim 1, characterized in that, The curtain (30) has a fixed end (31) and a hanging end (32), the fixed end (31) being connected to the roller tube (20), and the hanging end (32) being able to extend out of or retract into the box body (10). The vehicle projection screen device (100) also includes an arm mechanism (70), which is mounted on the housing (10) and connected to the hanging end (32). The arm mechanism (70) has a folded state and an unfolded state. When the arm mechanism (70) switches between the folded state and the unfolded state, it can be folded into the housing (10) or unfolded to the outside of the housing (10) to drive the hanging end (32) to move in the lifting direction of the screen (30).

9. A control method, implemented based on the vehicle projection screen device (100) according to any one of claims 1-8, characterized in that, The control method (200) includes: During the process of the friction disc (53) moving gradually toward the brake disc (51), the voltage U of the electromagnet (55) at the current time t0 is obtained, and the voltage U is greater than or equal to U1; where U1 is set as the maximum voltage connected to the electromagnet (55) when F1 equals F2; The voltage U is gradually reduced by a preset amplitude threshold until the voltage U is zero.

10. The control method according to claim 9, characterized in that, The step of gradually reducing the voltage U by a preset amplitude threshold until the voltage U is zero includes: The voltage U is gradually reduced to U1 by a first preset amplitude threshold, so that F1 equals F2; The voltage U1 is gradually reduced to U2 by the second preset amplitude threshold. When the voltage is U2, the elastic element (54) is gradually reset and F1 increases, F2 decreases and is in a balanced state. When the voltage is U2, the friction disc (53) begins to contact the brake disc (51). U2 continues to decrease gradually with the third preset amplitude threshold until it reaches zero. At this time, under the action of the elastic element (54), the friction disc (53) squeezes the brake disc (51) and forms a friction fit.

11. A vehicle, characterized in that, The vehicle includes a vehicle body and a vehicle projection screen device (100) as described in any one of claims 1-8, the vehicle projection screen device (100) being mounted on the vehicle body.

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