CN209070298U - A kind of Portable projection screen cloth holder - Google Patents

Abstract

The utility model relates to the technical field of projection equipment, in particular to a portable projection screen frame, comprising a fixed box body, a lifting bearing plate, a screen rolling frame and a screen fixing device. Before using the device, the universal wheel is self-locking , turn the fixing bolt to let the fixing bolt separate from the fixing box, open the upper cover, turn the lead screw clockwise, and the clockwise lead screw drives the bearing plate to move upward. Pull the positioning cylinder back, pull the lifting cylinder upwards, insert the positioning cylinder into the corresponding positioning hole according to the height of the projector, take out the curtain wrapped around the winding barrel, pull the sliding column back, and the sliding column will drive the clamping plate backward Move, put one end of the curtain between the connecting block and the clamping plate, release the sliding column, use the elastic potential energy of the spring, the rear end of the spring is limited by the sliding plate, then the spring will push the clamping plate forward. move forward to secure the screen between the connecting block and the clamping plate.

Description

A portable projection screen stand

technical field

The utility model relates to the technical field of projection equipment, in particular to a portable projection screen stand.

Background technique

Now there is a portable projection screen stand with a patent number of CN201721117424.1, which includes a box body, an inner cavity is arranged inside the box body, and one end of the cavity bottom of the inner cavity is rotatably connected with a support rod through a first hinge. The top is sleeved with a first set of rods, the top of the first set of rods is sleeved with a second set of rods, the top of the second set of rods is rotatably connected with a support frame, and the two ends of the support frame are respectively provided with a first clamping block and a second clamping block The first block is connected to one end of the support frame through the second hinge, and the second block is fixedly connected to the other end of the support frame. There is a hanging rod, one end of the hanging rod is fixedly connected with the second clamping block, and the other end is movably clamped with the first clamping block, and the end of the cavity bottom of the box cavity away from the support rod is rotatably connected with a top rod, and the top rod is movable with the support frame connect. However, the utility model is inconvenient to move, and the upper and lower ends of the curtain cannot be fixed, and the curtain is prone to shaking, which affects the viewing effect.

SUMMARY OF THE INVENTION

The utility model relates to the technical field of projection equipment, in particular to a portable projection screen frame, comprising a fixed box, a lifting bearing plate, a screen rolling frame and a screen fixing device. The device can adjust the height of the screen according to the height of the projector. The height and the upper and lower ends of the screen are fixed, and it is more convenient to use the universal wheel to move.

The fixed box body includes a fixed box, a hinge, an upper cover, a fixed bolt, a universal wheel and a limit slide I. The fixed box is hingedly connected with the upper cover through the hinge, and the fixed bolt is slidably connected with the upper cover, and is fixed. The bolts pass through the upper cover and are connected with the fixing box by threads, the four corners of the lower surface of the fixing box are fixedly connected with universal wheels, and the rear side of the front end inside the fixing box is provided with a limited slideway I;

The lifting bearing plate includes a bearing plate, a limit bump I, a fixed block, a bearing and a lead screw, the front end of the bearing plate is fixedly connected with the limit bump I, and the limit bump I is slidably connected in the limit slideway I. , the fixed block is fixedly connected to the front side of the inner rear end of the fixed box, the fixed block is fixedly connected to the outer ring of the bearing, the lead screw is fixedly connected to the inner ring of the bearing, and the lead screw is connected to the bearing plate through thread transmission;

The curtain rolling frame includes a bearing seat, a rotating shaft and a winding barrel, two bearing seats are fixedly connected on the bearing plate, the winding barrel is fixedly connected on the rotating shaft, and both ends of the rotating shaft are respectively rotatably connected with the two bearing seats;

The curtain fixing device includes a limit sliding cavity, a keyway, a lifting cylinder, a key, a jack, a positioning hole, a positioning cylinder, a connecting block, a connecting plate, a limit slideway II, a clamping plate, a limit bump II, The sliding plate, the sliding column and the spring, the limit sliding cavity is fixedly connected to the bearing plate, the limit sliding cavity is symmetrically arranged with two key grooves, the lifting cylinder is symmetrically and fixedly connected with two keys, and the lifting cylinder and the two keys are respectively slidably connected In the limit sliding cavity and the two key grooves, the upper end of the limit sliding cavity is provided with an insertion hole, the lifting cylinder is provided with a plurality of positioning holes, the positioning cylinder is slidably connected in the insertion hole, and the positioning cylinder is slidably connected to the insertion hole through the insertion hole. In one of the multiple positioning holes, the connecting block is fixedly connected to the upper end of the lifting cylinder, the connecting block is fixedly connected with a connecting plate, the connecting plate is provided with two limit slides II, and the clamping plate is fixedly connected with two limiters. Position bump II, the two limit bumps II are respectively slidably connected in the two limit slideways II, the rear end of the connecting plate is fixedly connected with a sliding plate, the sliding plate is slidably connected with the sliding column, and the sliding column is fixedly connected with the clamping plate , a spring is set on the sliding column, and the spring is located between the clamping plate and the sliding plate.

As a further optimization of the technical solution, the fixed box body of the portable projection screen frame of the present invention further comprises a handle, and the handle is fixedly connected to the upper end of the upper cover;

As a further optimization of the technical solution, the lifting bearing plate of the portable projection screen stand of the present invention further comprises a handle, and the handle is fixedly connected to the upper end of the lead screw.

As a further optimization of the technical solution, a projection screen is wound on the winding barrel of a portable projection screen stand of the present invention.

As a further optimization of the technical solution, the curtain fixing device described in the portable projection screen stand of the present invention further comprises a limit ring and a handle, the limit ring is fixedly connected to the rear end of the positioning cylinder, and the handle is fixedly connected to the slide rear end of the column.

As a further optimization of the technical solution, the universal wheel of the portable projection screen frame of the present invention has a self-locking function.

The beneficial effects of the portable projection screen frame of the utility model are as follows:

Before using this device, first self-lock the universal wheel, turn the fixing bolts to release the fixing bolts from the fixing box, open the upper cover, and turn the lead screw clockwise. When it is in contact with the fixed block, stop rotating the screw, pull the positioning cylinder backward, and pull the lifting cylinder upward. According to the height of the projector, insert the positioning cylinder into the corresponding positioning hole, take out the curtain wrapped around the winding barrel, and move it backward. Pull the sliding column, the sliding column drives the clamping plate to move backward, put one end of the curtain between the connecting block and the clamping plate, release the sliding column, use the elastic potential energy of the spring, the rear end of the spring is limited by the sliding plate, this At this time, the spring will move forward against the clamping plate, so as to fix the curtain between the connecting block and the clamping plate. The ground contact can push the device away, or the device can be picked up by pulling the handle by hand, and the device can be moved by two methods.

Description of drawings

The present utility model will be described in further detail below in conjunction with the accompanying drawings and specific implementation methods.

1 is a schematic structural diagram of a portable projection screen frame of the present invention;

Fig. 2 is a kind of partial structure schematic diagram of portable projection screen frame;

Figure 3 is a schematic diagram of the structure of the fixed box;

Figure 4 is a schematic diagram of the structure of a part of the fixed box;

FIG. 5 is a schematic structural diagram of a lifting bearing plate;

Fig. 6 is a schematic diagram of the structure of the curtain rolling frame;

Figure 7 is a schematic structural diagram of a curtain fixing device;

Fig. 8 is a partial structural schematic diagram 1 of the curtain fixing device;

FIG. 9 is a second schematic diagram of the partial structure of the curtain fixing device;

Fig. 10 is a schematic diagram 3 of the partial structure of the curtain fixing device.

In the figure: fixed box 1; fixed box 1-1; hinge 1-2; upper cover 1-3; fixing bolts 1-4; universal wheel 1-5; limit slide I1-6; handle 1- 7; Lifting bearing plate 2; Bearing plate 2-1; Limiting bump I2-2; Fixed block 2-3; Bearing 2-4; Screw 2-5; Handle 2-6; Curtain rolling frame 3; Bearing seat 3-1; rotating shaft 3-2; winding barrel 3-3; curtain fixing device 4; limit sliding cavity 4-1; keyway 4-2; lifting cylinder 4-3; key 4-4; socket 4-5 ; Positioning hole 4-6; Positioning cylinder 4-7; Connecting block 4-8; Connecting plate 4-9; Limiting slideway II4-10; Clamping plate 4-11; Limiting bump II4-12; -13; sliding column 4-14; spring 4-15; limit ring 4-16; handle 4-17.

Detailed ways

Specific implementation one:

The present embodiment will be described below with reference to FIGS. 1 to 10. The present utility model relates to the technical field of projection equipment, and more specifically, to a portable projection screen frame, comprising a fixed box 1, a lifting bearing plate 2, a screen rolling frame 3 and a screen fixing Device 4, before using this device, first self-lock the universal wheel 1-5, turn the fixing bolts 1-4, let the fixing bolts 1-4 separate from the fixing box 1-1, open the upper cover 1-3, and turn clockwise The lead screw 2-5, the lead screw 2-5 that rotates clockwise drives the bearing plate 2-1 to move upward, when the bearing plate 2-1 is in contact with the fixed block 2-3, stop rotating the lead screw 2-5 and pull it backward Positioning cylinder 4-7, pull up the lifting cylinder 4-3, insert the positioning cylinder 4-7 into the corresponding positioning hole 4-6 according to the height of the projector, take out the curtain wrapped around the winding barrel 3-3, and move it toward the Pull back the sliding column 4-14, the sliding column 4-14 drives the clamping plate 4-11 to move backward, put one end of the curtain between the connecting block 4-8 and the clamping plate 4-11, release the sliding column 4 -14. Using the elastic potential energy of the spring 4-15, the rear end of the spring 4-15 is limited by the slide plate 4-13. At this time, the spring 4-15 will push the clamping plate 4-11 forward and move forward, thereby Fix the curtain between the connecting block 4-8 and the clamping plate 4-11. After using the device, release the self-locking of the universal wheel, and use the contact between the universal wheel 1-5 and the ground to make the device Push away, you can also pull the handle 1-7 to pick up the device, and move the device in two ways;

The fixed box 1 includes a fixed box 1-1, a hinge 1-2, an upper cover 1-3, a fixed bolt 1-4, a universal wheel 1-5 and a limit slide I1-6, and the fixed box 1 -1 plays the role of bearing and fixing. The upper cover 1-3 is hingedly connected to the fixing box 1-1 through the hinge 1-2, and the fixing box 1-1 and the upper cover 1-3 can be hinged through the hinge 1-2. Together, the upper cover 1-3 can seal the fixing box 1-1, the fixing bolts 1-4 are slidably connected with the upper cover 1-3, and the fixing bolts 1-4 pass through the upper cover 1-3 and pass through the fixing box 1-1 Threaded connection, the fixing bolts 1-4 can fix the fixing box 1-1 and the upper cover 1-3 together. The four corners of the lower surface of the fixing box 1-1 are fixedly connected with universal wheels 1-5. The steering wheel 1-5 can rotate on the ground, which generates a small friction force, which is convenient for the movement of the device. The rear side of the inner front end of the fixed box 1-1 is provided with a limit slide I1-6, and the limit slide I1-6 can be Provide a sliding space for the limit bump I2-2;

The lifting bearing plate 2 includes a bearing plate 2-1, a limit bump I2-2, a fixing block 2-3, a bearing 2-4 and a lead screw 2-5, and the bearing plate 2-1 plays the role of bearing connection , can drive the curtain rolling frame 3 and the curtain fixing device 4 to move up and down, the front end of the carrier plate 2-1 is fixedly connected with the limit bump I2-2, and the limit bump I2-2 is slidably connected in the limit slide I1-6. , when the limit bump I2-2 is slidably connected in the limit slideway I1-6, the carrier plate 2-1 can be limited. At this time, the carrier plate 2-1 can only move up and down, and the fixed block 2-3 It is fixedly connected to the front side of the inner rear end of the fixed box 1-1. The fixed block 2-3 can provide a fixed space for the bearing 2-4. The fixed block 2-3 is fixedly connected with the outer ring of the bearing 2-4. The bearing 2- 4. It can limit the screw 2-5, so that the screw 2-5 can only rotate around its own axis, the screw 2-5 is fixedly connected with the inner ring of the bearing 2-4, and the rotating screw 2-5 can drive the The bearing plate 2-1 moves up and down, and the lead screw 2-5 is connected with the bearing plate 2-1 through screw drive;

The curtain rolling frame 3 includes a bearing seat 3-1, a rotating shaft 3-2 and a winding barrel 3-3, and two bearing seats 3-1 are fixedly connected to the bearing plate 2-1, and the two bearing seats 3-1 The rotating shaft 3-2 can be limited, so that the rotating shaft 3-2 can only rotate around its own axis. The rotating shaft 3-2 is fixedly connected with a winding barrel 3-3, and the rotating shaft 3-2 can be used for the winding barrel 3-2. 3. Provide a fixed space, the curtain can be wound on the winding barrel 3-3, and the two ends of the rotating shaft 3-2 are respectively rotatably connected with the two bearing seats 3-1;

The curtain fixing device 4 includes a limit sliding cavity 4-1, a key slot 4-2, a lifting cylinder 4-3, a key 4-4, an insertion hole 4-5, a positioning hole 4-6, a positioning cylinder 4-7, Connecting block 4-8, connecting plate 4-9, limit slide II4-10, clamping plate 4-11, limit bump II4-12, slide plate 4-13, sliding column 4-14 and spring 4-15 , the limit sliding cavity 4-1 is fixedly connected to the bearing plate 2-1, the limit sliding cavity 4-1 can provide a sliding space for the lifting cylinder 4-3, and the limit sliding cavity 4-1 is symmetrically arranged with two A keyway 4-2, the keyway 4-2 can provide a sliding space for the key 4-4, the lifting cylinder 4-3 is symmetrically and fixedly connected with two keys 4-4, the lifting cylinder 4-3 and the two keys 4- 4 are slidably connected in the limit sliding cavity 4-1 and the two key grooves 4-2 respectively. When the two keys 4-4 are slidably connected in the two key grooves 4-2 respectively, the lifting cylinder 4-3 is limited. At this time, the lifting cylinder 4-3 can only slide up and down, and the upper end of the limit sliding cavity 4-1 is provided with a socket 4-5. The socket 4-5 can provide a space for the positioning cylinder 4-7 to insert, and the lifting cylinder 4-3 is provided with a plurality of positioning holes 4-6. When the positioning cylinders 4-7 are slidably connected in different positioning holes 4-6, the heights of the curtains are also different. The positioning cylinders 4-6 are determined according to the height of the projector. 7. Which positioning hole 4-6 is slidably connected in, the positioning cylinder 4-7 is slidably connected in the insertion hole 4-5, and the positioning cylinder 4-7 is slidably connected to the plurality of positioning holes 4-6 through the insertion hole 4-5. In one, the positioning cylinder 4-7 plays the role of fixing the height, the connecting block 4-8 is fixedly connected to the upper end of the lifting cylinder 4-3, the connecting block 4-8 plays the role of fixed connection, and the connecting block 4-8 is fixed on the The connecting plate 4-9 is connected, and the connecting plate 4-9 is provided with two limit slides II4-10, the limit slides II4-10 can provide a sliding space for the limit bump II4-12, and the clamping The plate 4-11 is fixedly connected with two limit bumps II4-12, which can be fixed to the upper end of the screen. The two limit bumps II4-12 are slidably connected to the two limit slides II4-10. When the two limit bumps II4-12 are slidably connected to the two limit slides II4-10, the clamping plate 4-11 is limited, and the clamping plate 4-11 can only slide back and forth, connecting The rear end of the plate 4-9 is fixedly connected with a sliding plate 4-13, the sliding plate 4-13 can provide a sliding space for the sliding column 4-14, the sliding plate 4-13 is slidably connected with the sliding column 4-14, and the sliding column 4-14 It can drive the clamping plate 4-11 to move, the sliding column 4-14 is fixedly connected with the clamping plate 4-11, the sliding column 4-14 is covered with a spring 4-15, and the spring 4-15 is located between the clamping plate 4-11 and the clamping plate 4-11. Between the slide plates 4-13, using the elastic potential energy of the spring 4-15, the rear end of the spring 4-15 is limited by the slide plate 4-13. At this time, the spring 4-15 will push the clamping plate 4-11 forward. move forward, thereby securing the curtain between the connecting block 4-8 and the clamping plate 4-11.

Specific implementation two:

The present embodiment will be described below with reference to FIGS. 1-10 . This embodiment will further describe the first embodiment. The fixed box body 1 further includes a handle 1-7, and the handle 1-7 is fixedly connected to the upper end of the upper cover 1-3. Pull the handle 1-7. Handles 1-7 can lift the device to achieve movement;

Specific implementation three:

The present embodiment will be described below with reference to FIGS. 1-10. This embodiment will further describe the first embodiment. The lifting bearing plate 2 further includes a handle 2-6. The handle 2-6 is fixedly connected to the upper end of the lead screw 2-5, and rotates The handle 2-6 can easily drive the screw 2-5 to rotate.

Specific implementation four:

The present embodiment is described below with reference to FIGS. 1-10 . This embodiment further describes the first embodiment. The winding barrel 3 - 3 is wound with a projection screen.

Specific implementation five:

The present embodiment will be described below with reference to Figs. 1-10. This embodiment will further describe the first embodiment. The curtain fixing device 4 further includes a limit ring 4-16 and a handle 4-17, and the limit ring 4-16 is fixed Connected to the rear end of the positioning cylinder 4-7, the limit ring 4-16 can limit the position of the positioning cylinder 4-7, and pulling the limit ring 4-16 can easily drive the positioning cylinder 4-7 to move, and the handle 4 -17 is fixedly connected to the rear end of the sliding column 4-14, and pulling the handle 4-17 can easily drive the sliding column 4-14 to slide.

Specific implementation six:

The present embodiment will be described below with reference to Figs. 1-10. This embodiment will further describe Embodiment 1. The universal wheels 1-5 have their own self-locking function. When the device is used, the device needs to be fixed, so the universal wheel 1-5 must have self-locking function, according to the demand, go to the market to choose the existing universal wheel 1-5.

The working principle of a portable projection screen frame of the utility model:

Before using this device, first self-lock the universal wheel 1-5, the fixing bolts 1-4 pass through the upper cover 1-3 and connect with the fixing box 1-1 through threads, turn the fixing bolts 1-4, and let the fixing bolts 1-4 4. Leave the fixed box 1-1, open the upper cover 1-3 through the hinge 1-2, turn the handle 2-6 clockwise, the handle 2-6 is fixedly connected to the upper end of the screw 2-5, and the handle 2-6 drives the The lead screw 2-5 rotates clockwise, and the lead screw 2-5 is connected with the bearing plate 2-1 through a screw drive. The clockwise lead screw 2-5 drives the bearing plate 2-1 to move upward. When the fixed block 2-3 is in contact, stop rotating the screw 2-5, pull the limit ring 4-16 backward, the limit ring 4-16 drives the positioning cylinder 4-7, and pulls the lifting cylinder 4-3 upward, according to the The height of the projector, insert the positioning cylinder 4-7 into the corresponding positioning hole 4-6, take out the curtain wrapped around the winding barrel 3-3, pull the handle 4-17 backward, and the handle 4-17 is fixedly connected to the slide. The rear end of the column 4-14 drives the sliding column 4-14 to move backward, the sliding column 4-14 is fixedly connected with the clamping plate 4-11, the sliding column 4-14 drives the clamping plate 4-11 to move backward, and the curtain Put one end of the connecting rod between the connecting block 4-8 and the clamping plate 4-11, release the handle 4-17, the sliding column 4-14 is covered with a spring 4-15, and the spring 4-15 is located on the clamping plate 4-11 Between the sliding plate 4-13 and the elastic potential energy of the spring 4-15, the rear end of the spring 4-15 is limited by the sliding plate 4-13. At this time, the spring 4-15 will push the clamping plate 4-11 forward. Move forward to fix the curtain between the connecting block 4-8 and the clamping plate 4-11. After using the device, pull the handle 4-17, the curtain will fall at this time, and wrap the curtain around the winding barrel 3-3, then drop the lifting cylinder 4-3 to the lowest point, turn the screw 2-5 to move the carrier plate 2-1 to the lowest point, and then use the fixing bolts 1-4 to put the upper cover 1-3 and Fix the box 1-1 together, release the self-locking of the universal wheel, the universal wheel 1-5 can rotate on the ground, and generate a small friction force, which is convenient for the movement of the device. You can also pull the handle 1- 7Pick up the unit and move the unit in two ways.

Of course, the above description does not limit the present utility model, and the present utility model is not limited to the above-mentioned examples. Changes, modifications, additions or replacements made by those of ordinary skill in the technical field within the essential scope of the present utility model also belong to the scope of the present utility model. The scope of protection of the utility model.

Claims (6)

1. a kind of Portable projection screen cloth holder, including static housing (1), lifting loading plate (2), curtain rolling frame (3) and curtain Fixed device (4), it is characterised in that: the static housing (1) include fixed case (1-1), hinge (1-2), upper cover (1-3), Fixing bolt (1-4), universal wheel (1-5) and limit slideway I (1-6), are articulated and connected on fixed case (1-1) by hinge (1-2) Have upper cover (1-3), fixing bolt (1-4) is slidably connected with upper cover (1-3), and fixing bolt (1-4) passes through upper cover (1-3) and fixed Case (1-1) is connected through a screw thread, and is fixedly connected to universal wheel (1-5), fixed case on four angles of the lower surface fixed case (1-1) Limit slideway I (1-6) is provided on rear side of (1-1) interior forward end；

The lifting loading plate (2) include loading plate (2-1), spacing block set I (2-2), fixed block (2-3), bearing (2-4) and Lead screw (2-5), the front end of loading plate (2-1) are fixedly connected with spacing block set I (2-2), and spacing block set I (2-2) is slidably connected at Limit in slideway I (1-6), fixed block (2-3) is fixedly connected on the front side of fixed case (1-1) Internal back end, fixed block (2-3) with The outer ring of bearing (2-4) is fixedly connected, and lead screw (2-5) is fixedly connected with the inner ring of bearing (2-4), lead screw (2-5) and loading plate (2-1) is connected by screw-driven；

The curtain rolling frame (3) includes bearing block (3-1), rotation axis (3-2) and winds bucket (3-3), on loading plate (2-1) There are two being fixedly connected bearing block (3-1), it is fixedly connected in rotation axis (3-2) and winds bucket (3-3), the two of rotation axis (3-2) End is rotatablely connected with two bearing blocks (3-1) respectively；

The curtain fixed device (4) includes spacing sliding chamber (4-1), keyway (4-2), elevation cylinder (4-3), key (4-4), inserts Hole (4-5), location hole (4-6), positioning cylinder (4-7), link block (4-8), connecting plate (4-9), limit slideway II (4-10), folder Tight plate (4-11), spacing block set II (4-12), slide plate (4-13), traveller (4-14) and spring (4-15), spacing sliding chamber (4-1) are solid Surely it is connected on loading plate (2-1), is symmetrical arranged in spacing sliding chamber (4-1) there are two keyway (4-2), in elevation cylinder (4-3) There are two being symmetrically fixedly connected key (4-4), elevation cylinder (4-3) and two keys (4-4) are slidably connected at spacing sliding chamber (4- respectively 1) and in two keyways (4-2), the upper end of spacing sliding chamber (4-1) is provided with jack (4-5), is provided in elevation cylinder (4-3) Multiple location holes (4-6), positioning cylinder (4-7) are slidably connected in jack (4-5), and positioning cylinder (4-7) passes through jack (4-5) Multiple location holes (4-6) are slidably connected in one of them, link block (4-8) is fixedly connected on the upper end of elevation cylinder (4-3), It is fixedly connected on link block (4-8) connecting plate (4-9), setting is pressed from both sides there are two slideway II (4-10) is limited on connecting plate (4-9) It is fixedly connected on tight plate (4-11) there are two spacing block set II (4-12), two spacing block set II (4-12) are slidably connected at respectively In two limit slideway II (4-10), the rear end of connecting plate (4-9) is fixedly connected with slide plate (4-13), slide plate (4-13) and traveller (4-14) is slidably connected, and traveller (4-14) is fixedly connected with clamping plate (4-11), and spring (4-15), bullet are cased on traveller (4-14) Spring (4-15) is located between clamping plate (4-11) and slide plate (4-13).

2. a kind of Portable projection screen cloth holder according to claim 1, it is characterised in that: the static housing (1) is also Including handle (1-7), handle (1-7) is fixedly connected on the upper end of upper cover (1-3).

3. a kind of Portable projection screen cloth holder according to claim 1, it is characterised in that: the lifting loading plate (2) It further include handle (2-6), handle (2-6) is fixedly connected on the upper end of lead screw (2-5).

4. a kind of Portable projection screen cloth holder according to claim 1, it is characterised in that: on the winding bucket (3-3) It is wound with projection screen.

5. a kind of Portable projection screen cloth holder according to claim 1, it is characterised in that: the fixed device of the curtain It (4) further include limit annulus (4-16) and knob (4-17), after limit annulus (4-16) is fixedly connected on positioning cylinder (4-7) End, knob (4-17) are fixedly connected on the rear end of traveller (4-14).

6. a kind of Portable projection screen cloth holder according to claim 1, it is characterised in that: the universal wheel (1-5) is certainly Band self-locking function.