A portable projection screen device

Abstract

The present invention discloses a portable projection screen device, including a projection screen, an articulated seat, an articulated rod, a base and two symmetrically distributed half shells, the two half shells can be spliced into a whole shell, the two half shells are both provided with a screen reel, a screw rod, a driving motor, a nut pair, a pressure plate, a universal wheel bracket, a pull rod, a battery and a roller bracket, the two ends of the projection screen are respectively fixed on the two screen reels, the driving motor drives the screen reel to rotate, the screen reel rotates to unwind the projection screen, the screen reel drives the screw rod to rotate, the nut pair is raised and lowered to make the two articulated rods face each other to open the two spliced half shells, and the universal wheel will be rotated out together, and the projection screen can be easily moved to a position through the universal wheel after it is unfolded. The present invention uses a handle to pull the device, which is easy to carry, and is provided with rollers, which is easy to move, and is suitable for a variety of temporary projection work occasions. When not in use, the two half shells are spliced into a whole shell, which is convenient for transportation and storage.

Description

Technical Field

[0001] The present invention relates to the technical field of projection screens, and in particular to a portable projection screen device. Background Art

[0002] With the advent of projectors, teaching or briefing work can be carried out more quickly and conveniently. Projection screens are tools used in movie theaters, offices, home theaters, large conferences, etc. to display images and video files. Different projection screens are selected for different spaces.

[0003] Existing projection screens are usually fixed on walls to facilitate the projection of images to be displayed by projectors. However, if there is no projection screen installed in a teaching or briefing venue, or if temporary projection work is carried out in some occasions, it is necessary to temporarily set up a projection screen. However, the setup work of the projection screen is rather cumbersome, and the preparation of the projection screen will become a major trouble, which needs to be further improved to facilitate the progress of teaching or briefing work. Therefore, it is necessary to develop a portable projection screen device to solve this problem. Summary of the Invention

[0004] The purpose of the present invention is to solve the above problems and design a portable projection screen device.

[0005] The technical solution of the present invention for achieving the above-mentioned purpose is: a portable projection screen device, comprising a projection screen, an articulated seat, an articulated rod, a base and two symmetrically distributed half shells, the half shells are provided with a reeling switch and an unreeling switch for controlling the operation of a driving motor, the articulated seat is fixed on the base, two symmetrically distributed articulated rods are hinged on the articulated seat, the two half shells can be spliced into a whole shell, the two half shells are each provided with a screen reel, a screw rod, a driving motor, a nut pair, a pressure plate, a universal wheel bracket, a pull rod, a battery and a roller bracket, the two ends of the projection screen are respectively fixed on two screen reels, the screen reel and the screw rod are parallel, the lower end of the screen reel is rotatably mounted on the lower end surface of the half shell through a first bearing, the output end of the driving motor is connected to the top end of the screen reel, the upper end of the screen reel is provided with a first gear, the screw rod is parallel to the screw rod, the lower end of the screen reel is rotatably mounted on the lower end surface of the half shell, the output end of the driving motor is connected to the top end of the screen reel, the upper end of the screen reel is provided with a first gear, and the screw rod is parallel to the screw rod. The upper and lower ends of the rod are rotatably mounted on the upper and lower end surfaces of the half shell through two second bearings, and the upper end of the screw rod is mounted on the second gear meshing with the first gear, and the screw rod is threadedly connected to a nut pair, and the nut pair is hinged to the hinge rod on the opposite side of the half shell, and a roller bracket and two symmetrically distributed universal wheel brackets are hinged at the bottom of the half shell, and the universal wheel bracket is also connected to the inner wall of the bottom end of the half shell by a spring, and a universal wheel is installed on the universal wheel bracket, and the pressure plate is fixedly connected to the nut pair. When the pressure plate descends, it presses the two universal wheel brackets so that they are screwed out from the openings on the two side walls of the half shell, and a roller is installed at one end of the roller bracket, one end of the pull rod is located in the half shell and is movably connected to the pull rod, and the other end extends out of the half shell, one of the pull rods is hinged to a handle, and the handle can be clamped with the other pull rod after the two half shells are spliced into a whole shell. The half shell is provided with a reeling switch and an unreeling switch for controlling the operation of the drive motor. When using the projection screen, first unscrew the handle from the pull rod connected thereto, and the two half shells are no longer connected together. Press the unreeling switch, and the battery powers the drive motor. The drive motor is a stepper motor. The drive motors in the two half shells work at the same time, and the drive motor drives the screen reel to rotate. The screen reel unwinds the projection screen. The rotation directions of the two drive motors are opposite, so that the projection screen can be unwound at the same time. The screen reel drives the second gear and the lead screw to rotate through the first gear, and the nut pair converts the rotational motion of the lead screw into linear motion and moves downward. The two The nut pair descends synchronously, and the nut pair drives one end of the hinged rod to descend. The two hinged rods open the two half shells, and the half shells gradually slide out from the base; the pressure plate descends together with the nut pair, and the descent of the pressure plate will open the two universal wheel brackets. The distance between the upper ends of the two universal wheel brackets is larger than the size of the corresponding sides of the pressure plate, so that the pressure plate can pass through the gap between the upper ends of the two universal wheel brackets and gradually open the two universal wheel brackets synchronously. The universal wheel bracket and the universal wheel are rotated out from the opening, and the spring is compressed. When the universal wheel bracket is completely rotated out, the drive motor stops rotating, and the four universal wheels jointly support the entire device. At this time, the projection screen is also unrolled;

[0006] After use, press the reel switch, the battery supplies power to the drive motor, the drive motor drives the screen reel to rotate in the opposite direction, the screen reel reels the projection screen, the lead screw drives the nut pair and the pressure plate to rise, the hinged rod pulls the half shell to bring the two half shells together and gradually splice them into one, the universal wheel bracket is gradually screwed into the half shell by the elastic restoring force of the spring, when the two half shells are spliced into a whole, the drive motor stops rotating, rotates the handle, and the U-shaped groove of the handle clamps the pull rod; when the device needs to be moved, lift the handle, and the limit ring clamps the handle. The hand makes the handle drive the pull rod to rise, and the hinged section of the pull rod moves in the limit opening. The circular baffle will resist the roller bracket to prevent the hinged section of the pull rod from leaving the limit opening. The pull rod drives one end of the roller bracket to rotate up, and the end of the roller bracket connected to the roller is rotated out from the opening. After the roller is rotated out, it has a certain inclination angle. At this time, the concave limiting portion of the pull rod is located at the ring, and then the limiting bead is screwed, and the limiting bead is rotated to the concave limiting portion, thereby fixing the pull rod, and then the handle is pulled at an angle. The entire device can be easily moved under the support of the roller.

[0007] A collar is fixed on the top of the half shell, the upper end of the pull rod is inserted through the collar, the collar is radially tapped with a threaded hole, a limit bead is threadedly connected at the threaded hole, and a concave limit portion cooperating with the limit bead is provided at the upper end of the pull rod. When the concave limit portion of the pull rod is located at the collar, the limit bead is screwed, and the limit bead is rotated to the concave limit portion, thereby fixing the pull rod.

[0008] The roller bracket is hinged with the pull rod at one end with a long strip of limiting opening, the lower end of the pull rod is a hinged section with a radius smaller than the radius of the upper end thereof, the hinged section of the pull rod moves in the limiting opening, a circular baffle is fixed at the end of the hinged section of the pull rod for limiting the pull rod from being separated from the limiting opening, the width of the limiting opening is larger than the diameter of the hinged section of the pull rod and smaller than the diameter of the circular baffle, and the roller bracket is driven to tilt out of the opening when the pull rod is lifted. When the handle drives the pull rod to rise, the circular baffle will resist the roller bracket, and the hinged section of the pull rod only moves in the limiting opening to prevent the hinged section of the pull rod from being separated from the limiting opening.

[0009] The driving motors in the two half shells rotate in opposite directions when working at the same time, and the threads of the two screw rods are in opposite directions, so that the projection screen can be unwound and rewound at the same time, and the two nut pairs can be raised and lowered at the same time.

[0010] A limiting ring is fixed on the pull rod, and a U-shaped groove matching the limiting ring is provided at one end of the handle that is clamped with the pull rod. After the two half shells are spliced into a whole shell, the U-shaped groove of the handle can be rotated to a position to clamp the pull rod, and when the handle is lifted, the limiting ring clamps the handle, so that the handle can drive the pull rod to rise.

[0011] Four universal balls are installed on the bottom end surfaces of the two half shells, so that the half shells can slide into and out of the base easily.

[0012] Both sides of the base facing the two half - shells are inclined planes, so that the two half - shells can smoothly slide into and out of the base 4 along the inclined planes.

[0013] A portable projection screen device made by using the technical solution of the present invention can be easily carried by pulling the device with a handle, is provided with rollers for easy movement, is applicable to a variety of temporary projection work occasions. When in use, the driving motor drives the curtain roller and the lead screw to rotate, so that the projection screen is automatically unfolded. At the same time, the universal wheel bracket will also rotate downwards. After the projection screen is unfolded, it can be easily moved through the universal wheels. After use, the driving motor rotates in the reverse direction to roll up the projection screen. At the same time, the universal wheel bracket rotates into the half - shell, and the two half - shells are spliced into a whole shell, which is convenient for transportation and storage. Description of the Drawings

[0014] Figure 1 is a schematic structural diagram of a portable projection screen device according to the present invention;

[0015] Figure 2 is a schematic Figure 1 (when the projection screen is unrolled);

[0016] Figure 3 is a schematic Figure 2 (when the projection screen is rolled up);

[0017] Figure 4 is Figure 3 a partial enlarged view of A in;

[0018] Figure 5 is a side view of a portable projection screen device according to the present invention;

[0019] Figure 6 is a front view of a portable projection screen device according to the present invention;

[0020] Figure 7 is Figure 6 a cross - sectional view taken along A - A in;

[0021] Figure 8 is a schematic diagram of the pull rod according to the present invention;

[0022] Figure 9 is Figure 8 a partial enlarged view of B in;

[0023] Figure 10 is a connection schematic Figure 1 (natural state);

[0024] Figure 11Schematic diagram of the connection between the pull rod and the roller bracket in the present invention Figure 2 (lifting state);

[0025] Figure 12 is Figure 5 partial enlarged view at position C in

[0026] In the figure, 1, projection screen; 2, hinge seat; 3, hinge rod; 4, base; 5, half shell; 6, curtain reel; 7, lead screw; 8, drive motor; 9, nut pair; 10, pressing plate; 11, universal wheel bracket; 12, pull rod; 13, storage battery; 14, roller bracket; 15, first bearing; 16, first gear; 17, second bearing; 18, second gear; 19, spring; 20, universal wheel; 21, opening; 22, roller; 23, handle; 24, collar; 25, limit catch; 26, concave limit part; 27, limit port; 28, hinge section; 29, circular retaining plate; 30, limit ring; 31, U-shaped groove; 32, universal ball. Specific embodiments

[0027] The present invention will be specifically described below with reference to the accompanying drawings, as Figures 1-12As shown in the figure: The hinge seat 2 is fixed on the base 4. Two symmetrically distributed hinge rods 3 are hinged on the hinge seat 2. When the half shells 5 are spliced into a complete shell, they are located on the base 4. Inside the half shells 5, there are curtain rollers 6, lead screws 7, drive motors 8, nut pairs 9, pressing plates 10, universal wheel brackets 11, pull rods 12, storage batteries 13 and roller brackets 14. The drive motor 8 and the storage battery 13 are installed inside the half shells 5. Both ends of the projection curtain 1 are respectively fixed on the two curtain rollers 6. The curtain rollers 6 and the lead screws 7 are parallel. The lower end of the curtain roller 6 is rotatably installed on the lower end face of the half shell 5 through a first bearing 15. The output end of the drive motor 8 is connected to the top end of the curtain roller 6. A first gear 16 is installed at the upper end of the curtain roller 6. The upper and lower ends of the lead screw 7 are rotatably installed on the upper and lower end faces of the half shell 5 through two second bearings 17. A second gear 18 meshed with the first gear 16 is installed at the upper end of the lead screw 7. A nut pair 9 is threadedly connected to the lead screw 7. The nut pair 9 is hinged to the hinge rod 3 on its opposite side. Inside the bottom of the half shell 5, a roller bracket 14 and two symmetrically distributed universal wheel brackets 11 are hinged. The universal wheel bracket 11 is also connected to the inner wall of the bottom end of the half shell 5 through a spring 19. A universal wheel 20 is installed on the universal wheel bracket 11. The pressing plate 10 is fixedly connected to the nut pair 9. When the pressing plate 10 descends, it presses the two universal wheel brackets 11 to rotate out from the openings 21 on both sides of the half shell 5. One end of the roller bracket 14 is installed with a roller 22. One end of the pull rod 12 is located inside the half shell 5 and is movably connected to the pull rod 12, and the other end extends out of the half shell 5. One of the pull rods 12 is hinged to the handle 23. After the two half shells 5 are spliced into a complete shell, the handle 23 can be clamped with the other pull rod 12. On the half shell 5, there are a winding switch and an unwinding switch for controlling the operation of the drive motor 8. The drive motor 8 is a stepper motor;

[0028] A long strip-shaped limit opening 27 is opened at the end where the roller bracket 14 is hinged to the pull rod 12. The lower end of the pull rod 12 is a hinged section 28 with a radius smaller than that of its upper end. The hinged section 28 of the pull rod 12 moves inside the limit opening 27. A circular stop piece 29 for restricting the separation of the pull rod 12 from the limit opening 27 is fixed at the end of the hinged section 28 of the pull rod 12. The width of the limit opening 27 is greater than the diameter of the hinged section 28 of the pull rod 12 and smaller than the diameter of the circular stop piece 29. When the pull rod 12 is lifted, it drives the roller bracket 14 to tilt and extend out of the opening 21. When the handle 23 drives the pull rod 12 to rise, the circular stop piece 29 will abut against the roller bracket 14, and the hinged section 28 of the pull rod 12 only moves inside the limit opening 27, preventing the hinged section 28 of the pull rod 12 from detaching from the limit opening 27.

[0029] When the drive motors 8 in the two half shells 5 work simultaneously, their rotation directions are opposite, and the thread directions of the two lead screws 7 are opposite. Thus, the simultaneous unwinding and simultaneous winding of the projection curtain 1 are realized, enabling the two nut pairs 9 to rise and fall simultaneously;

[0030] A limiting ring 30 is fixed on the pull rod 12. One end of the handle 23 that is clamped with the pull rod 12 is provided with a U-shaped groove 31 that cooperates with the limiting ring 30. After the two half shells 5 are spliced into a whole shell, the U-shaped groove 31 of the handle 23 can be rotated to the position where it clamps the pull rod 12. When the handle 23 is lifted, the limiting ring 30 clamps the handle 23, so that the handle 23 can drive the pull rod 12 to rise;

[0031] Four universal balls 32 are installed on the bottom end surfaces of the two half shells 5, so as to facilitate the half shells 5 to slide into and out of the base 4;

[0032] Both side surfaces of the base 4 facing the two half shells 5 are inclined surfaces, so that the two half shells 5 can smoothly slide into and out of the base 4 from the inclined surfaces.

[0033] As Figures 3-4 shown: A collar 24 is fixed at the top end of the half shell 5. The upper end of the pull rod 12 passes through the collar 24. The collar 24 is radially tapped with a threaded hole. A limiting bead 25 is threadedly connected at the threaded hole. An inner concave limiting portion 26 that cooperates with the limiting bead 25 is provided at the upper end of the pull rod 12. When the inner concave limiting portion 26 of the pull rod 12 is located at the collar 24, the limiting bead 25 is screwed, and the limiting bead 25 will rotate to the inner concave limiting portion 26, thereby fixing the pull rod 12.

[0034] The working principle of this implementation scheme: The half shell 5 is provided with a winding switch and a unwinding switch for controlling the operation of the driving motor 8. When using the projection screen 1, first unscrew the handle 23 from the pull rod 12 with which it is clamped. The two half shells 5 are no longer connected together. Press the unwinding switch, and the storage battery 13 supplies power to the driving motor 8. The driving motor 8 is a stepping motor. The driving motors 8 in the two half shells 5 work simultaneously. The driving motor 8 drives the curtain reel 6 to rotate. The curtain reel 6 unwinds the projection screen 1. The rotation directions of the two driving motors 8 are opposite, so as to realize the simultaneous unwinding of the projection screen 1. The curtain reel 6 drives the second gear 18 and the lead screw 7 to rotate through the first gear 16. The nut pair 9 converts the rotational motion of the lead screw 7 into a linear motion and moves downward. The two nut pairs 9 descend synchronously. One end of the articulated rod 3 is driven by the nut pair 9 to descend. The two articulated rods 3 push the two half shells 5 apart by the reaction force. The half shell 5 gradually slides out of the base 4. The universal balls 32 support the movement of the half shell 5. The setting of the universal balls 32 facilitates the half shell 5 to slide out of the base 4 and avoids wear on the bottom of the half shell 5. The inclined surface can assist the universal balls 32 to make the half shell 5 slide out smoothly from the inclined surface of the base 4;

[0035] The pressure plate 10 descends together with the nut pair 9. The descent of the pressure plate 10 will open the two universal wheel brackets 11. The natural spacing between the upper ends of the two universal wheel brackets 11 is larger than the size of the corresponding sides of the pressure plate 10, so that the pressure plate 10 can pass through the gap between the upper ends of the two universal wheel brackets 11 and gradually contact the two universal wheel brackets 11 to open the two universal wheel brackets 11 synchronously. The universal wheel brackets 11 and the universal wheels 20 are rotated out from the opening 21, and the spring 19 is compressed. When the universal wheel bracket 11 is completely rotated out, the driving motor 8 stops rotating, and the four universal wheels 20 jointly support the entire device. At this time, the projection screen 1 is also unwound;

[0036] After use, the rewinding switch is pressed, and the battery 13 supplies power to the driving motor 8, which drives the screen reel 6 to rotate in the opposite direction, and the screen reel 6 rewinds the projection screen 1. The screw rod 7 drives the nut pair 9 and the pressure plate 10 to rise, and the hinge rod 3 pulls the half shell 5 to bring the two half shells 5 together and gradually splice them into one. The universal wheel bracket 11 is gradually screwed into the half shell 5 by the elastic restoring force of the spring 19, and the universal ball 32 begins to support the half shell 5. The half shell 5 slides onto the base 4 from the inclined surface through the universal ball 32. When the two half shells 5 are spliced into a whole, the driving motor 8 stops rotating, and the handle 23 is rotated so that the U-shaped groove 31 of the handle 23 clamps the pull rod 12; when the device needs to be moved, lift the handle 23. The limiting ring 30 clamps the handle 23, so that the handle 23 can drive the pull rod 12 to rise, and the hinged section 28 of the pull rod 12 moves in the limiting opening 27. The circular baffle 29 will resist the roller bracket 14 to prevent the hinged section 28 of the pull rod 12 from disengaging from the limiting opening 27. The pull rod 12 drives one end of the roller bracket 14 to rotate up, and the end of the roller bracket 14 connected to the roller 22 is rotated out from the opening 21. After the roller 22 is rotated out and has a certain inclination angle, the concave limiting portion 26 of the pull rod 12 is located at the ring 24 at this time, and then the limiting bead 25 is screwed, and the limiting bead 25 is rotated to the concave limiting portion 26, thereby fixing the pull rod 12, and then the handle 23 is tilted and pulled, and the entire device can be easily moved under the support of the roller 22.

[0037] The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Some changes that may be made to certain parts thereof by technicians in this technical field all reflect the principles of the present invention and fall within the protection scope of the present invention.

Claims

1. A portable projection screen device, comprising a projection screen (1), a hinge seat (2), hinge rods (3), a base (4) and two symmetrically distributed half shells (5). The hinge seat (2) is fixed on the base (4), and two symmetrically distributed hinge rods (3) are hinged on the hinge seat (2). The two half shells (5) can be spliced into a whole shell, characterized in that, Inside each of the two half - shells (5), there are provided a curtain roller (6), a lead screw (7), a driving motor (8), a nut pair (9), a pressing plate (10), a universal wheel bracket (11), a pull rod (12), a storage battery (13) and a roller bracket (14). Both ends of the projection curtain (1) are respectively fixed on the two curtain rollers (6). The curtain roller (6) and the lead screw (7) are parallel. The lower end of the curtain roller (6) is rotatably installed on the lower end surface of the half - shell (5) through a first bearing (15). The output end of the driving motor (8) is connected to the top end of the curtain roller (6). A first gear (16) is installed at the upper end of the curtain roller (6). The upper and lower ends of the lead screw (7) are rotatably installed on the upper and lower end surfaces of the half - shell (5) through two second bearings (17). A second gear (18) meshing with the first gear (16) is installed at the upper end of the lead screw (7). A nut pair (9) is threadedly connected to the lead screw (7). The nut pair (9) is hinged to the hinge rod (3) on its opposite side. Inside the bottom of the half - shell (5), a roller bracket (14) and two symmetrically distributed universal wheel brackets (11) are hinged. The universal wheel bracket (11) is also connected to the inner bottom wall of the half - shell (5) through a spring (19). A universal wheel (20) is installed on the universal wheel bracket (11). The pressing plate (10) is fixedly connected to the nut pair (9). When the pressing plate (10) descends, it presses the two universal wheel brackets (11) to rotate out from the openings (21) on both sides of the half - shell (5). One end of the roller bracket (14) is installed with a roller (22). One end of the pull rod (12) is inside the half - shell (5) and the other end extends out of the half - shell (5). One of the pull rods (12) is hinged to the handle (23). After the two half - shells (5) are spliced into a whole shell, the handle (23) can be clamped with the other pull rod (12). A collar (24) is fixed at the top of the half - shell (5). The upper end of the pull rod (12) passes through the collar (24). The collar (24) is radially tapped with a threaded hole, and a limit bead (25) is threadedly connected at the threaded hole. An inner concave limit portion (26) cooperating with the limit bead (25) is provided at the upper end of the pull rod (12). A long - strip - shaped limit opening (27) is opened at the end of the roller bracket (14) hinged to the pull rod (12). The lower end of the pull rod (12) is a hinged section (28) with a radius smaller than that of its upper end. The hinged section (28) of the pull rod (12) moves inside the limit opening (27). A circular retaining piece (29) for restricting the separation of the pull rod (12) from the limit opening (27) is fixed at the end of the hinged section (28) of the pull rod (12). The width of the limit opening (27) is greater than the diameter of the hinged section (28) of the pull rod (12) and smaller than the diameter of the circular retaining piece (29). When the pull rod (12) is lifted, it drives the roller bracket (14) to tilt and extend out of the opening (21).

2. The portable projection screen device according to claim 1, wherein When the driving motors (8) inside the two half - shells (5) work simultaneously, their rotation directions are opposite, and the thread directions of the two lead screws (7) are opposite.

3. A portable projection screen device according to claim 1, characterized in that A limiting ring (30) is fixed on the pull rod (12), and a U-shaped groove (31) matched with the limiting ring (30) is formed at one end of the handle (23) clamped with the pull rod (12).

4. A portable projection screen device according to claim 1, characterized in that, Four universal balls (32) are installed on the bottom end surfaces of the two half shells (5).

5. A portable projection screen device according to claim 1, characterized in that, Both side surfaces of the base (4) facing the two half shells (5) are inclined surfaces.

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