CN215264363U

CN215264363U - Projection screen

Info

Publication number: CN215264363U
Application number: CN202121803465.2U
Authority: CN
Inventors: 陈友才; 杨长明
Original assignee: Qingdao Hisense Laser Display Co Ltd
Current assignee: Qingdao Hisense Laser Display Co Ltd
Priority date: 2021-08-03
Filing date: 2021-08-03
Publication date: 2021-12-21
Anticipated expiration: 2031-08-03

Abstract

The embodiment of the application discloses a projection screen, and belongs to the technical field of projection. The projection screen includes: the device comprises a base, a curling mechanism, a lifting mechanism and a curtain sheet; the curling mechanism and the lifting mechanism are limited on the base; the first side edge of the curtain sheet is fixedly connected with the curling mechanism, the second side edge of the curtain sheet is fixedly connected with the lifting mechanism, and the first side edge is opposite to the second side edge; after the curtain sheet is unfolded, at least the part close to the third side edge and the part close to the fourth side edge are fixedly connected with the lifting mechanism, and the third side edge is opposite to the fourth side edge. In the embodiment of the application, fix the part that the curtain is close to the third side, the part that is close to the fourth side through elevating system after the curtain piece expandes, can realize the restraint to the left and right sides limit of curtain piece to avoid the curtain piece to take place the problem of fold and turn-up, and then avoided the problem that the display screen warp on the curtain piece, improved display effect.

Description

Projection screen

Technical Field

The embodiment of the application relates to the technical field of projection, in particular to a projection screen.

Background

With the continuous development of science and technology, projection equipment is more and more applied to the work and the life of people. At present, a projection device includes a projection host and a projection screen, where a light outlet of the projection host faces the projection screen to emit a projection light beam to the projection screen, and the projection screen is configured to receive the projection light beam to implement display of a picture. Wherein the projection screen is in an expanded state upon receiving the projection beam.

When the projection screen is in an expanded state, the screen included in the projection screen deforms in a direction perpendicular to the left and right sides due to factors such as internal stress and thermal expansion coefficient of the screen, for example, the screen has wrinkles, curled edges, and the like, thereby causing deformation of a display picture projected on the screen.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a projection screen, can avoid the curtain piece that projection screen includes to take place fold and turn-up, improves the display effect that shows the picture on the curtain piece. The technical scheme is as follows:

a projection screen, comprising: the device comprises a base, a curling mechanism, a lifting mechanism and a curtain sheet;

the curling mechanism and the lifting mechanism are limited on the base;

the first side edge of the curtain sheet is fixedly connected with the curling mechanism, the second side edge of the curtain sheet is fixedly connected with the lifting mechanism, and the first side edge is opposite to the second side edge;

after the curtain sheet is unfolded, at least the part close to the third side edge and the part close to the fourth side edge are fixedly connected with the lifting mechanism, and the third side edge is opposite to the fourth side edge.

The technical scheme provided by the embodiment of the application has the beneficial effects that at least:

in the embodiment of the application, fix the part that the curtain is close to the third side, the part that is close to the fourth side through elevating system after the curtain piece expandes, can realize the restraint to the left and right sides limit of curtain piece to avoid the curtain piece to take place the problem of fold and turn-up, and then avoided the problem that the display screen warp on the curtain piece, improved display effect.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic expanded structural view of a projection screen provided in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a curtain provided in an embodiment of the present application;

FIG. 3 is a schematic structural diagram of a curtain provided in an embodiment of the present application;

FIG. 4 is a schematic view of a projection screen according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a retracted projection screen provided in an embodiment of the present application;

FIG. 6 is a schematic view of an expanded structure of a projection screen according to an embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of a retracted projection screen provided in an embodiment of the present application;

fig. 8 is a schematic structural diagram of a projection screen provided in an embodiment of the present application;

FIG. 9 is a schematic view of an expanded projection screen according to an embodiment of the present disclosure;

FIG. 10 is a schematic view of an expanded projection screen according to an embodiment of the present disclosure;

FIG. 11 is a schematic view of a projection screen according to an embodiment of the present disclosure;

FIG. 12 is a schematic view of an expanded projection screen according to an embodiment of the present disclosure;

fig. 13 is a schematic structural diagram of a projection screen according to an embodiment of the present application.

Reference numerals:

1: a base; 2: a crimping mechanism; 3: a lifting mechanism; 4: a screen sheet; 5: a hold-down mechanism;

11: a protrusion; 12: a guide rail;

31: a first lifting frame; 32: a cross beam; 33: a second lifting frame; 34: a crimp member;

311: a first folding bar; 312: a second folding bar; 313: a first support bar; 314: a second support bar;

331: a third folding bar; 332: a fourth folding bar;

41: an optical film; 42: a flexible carrier;

51: a slider; 52: an adjusting screw; 53: and a pressure roller.

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present application more clear, the embodiments of the present application will be further described in detail with reference to the accompanying drawings.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs. The use of "first," second, "" third, "and the like in the description and in the claims does not denote any order, quantity, or importance, but rather the terms first," "second," and the like are used to distinguish one element from another. Also, the use of the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprise" or "comprises", and the like, means that the element or item listed before "comprises" or "comprising" covers the element or item listed after "comprising" or "comprises" and its equivalents, and does not exclude other elements or items.

Fig. 1 illustrates a schematic structural diagram of a projection screen according to an embodiment of the present application. As shown in fig. 1, the projection screen includes: the device comprises a base 1, a curling mechanism 2, a lifting mechanism 3 and a curtain sheet 4.

Wherein, the base 1 is used for providing a positioning base for the curling mechanism 2 and the lifting mechanism 3 so as to fix the curtain sheet 4 on the curling mechanism 2 and the lifting mechanism 3.

Optionally, as shown in fig. 1, the curling mechanism 2 and the lifting mechanism 3 are both limited on the base 1; the first side of

curtain

4 and 2 fixed connection of curling mechanism, the second side and the 3 fixed connection of elevating system of curtain 4, first side and second side are relative.

Wherein, base 1 includes base and holding portion, and the base is located the holding portion, and crimping mechanism 2 and elevating system 3 are all spacing on the base to realize sheltering from crimping mechanism 2 and elevating system 3 through the holding portion, improve projection screen's aesthetic property. In addition, when the screen 4 is stored, the screen is accommodated in the accommodating part, so that the phenomenon of dust falling on the screen 4 is avoided, and meanwhile, the damage of the screen 4 caused by collision of foreign objects and the like is avoided.

The specific structures of the curling mechanism 2 and the lifting mechanism 3 can refer to the related art, and the embodiment of the present application is not limited thereto. Illustratively, the winding mechanism 2 has a rotatable drum, and a first side of the screen 4 is fixedly connected to the drum. As shown in fig. 1, the lifting mechanism 3 comprises a first lifting frame 31 and a cross beam 32, the first lifting frame 31 is limited on the base 1, the first lifting frame 31 is connected with the cross beam 32, and the second side edge of the curtain sheet 4 is fixedly connected with the cross beam 32. Therefore, the curtain sheet 4 can be wound or unwound by the lifting of the first lifting frame 31 and the winding drum of the winding mechanism 2. Wherein, first crane 31 is for cutting fork formula crane, foldable crane or the formula crane that contracts of rising.

When first crane is for cutting fork formula crane or foldable crane, first crane passes through the articulated shaft spacing on the base, when first crane is the formula crane that contracts that rises, first crane passes through set screw etc. and spacing on the base.

In the embodiment of the present application, the curtain sheet 4 has a rectangular structure, and the first side edge and the second side edge of the curtain sheet 4 are the lower side edge and the upper side edge of the curtain sheet 4. The display screen on the screen 4 can also be adjusted to a rectangular structure to cover the display area of the screen 4, thereby improving the display effect of the display screen on the screen 4.

In some embodiments, as shown in fig. 2, the curtain sheet 4 includes an optical film 41, and a first side and a second side of the optical film 41 are fixedly connected to the curling mechanism 2 and the lifting mechanism 3, respectively. The optical film 41 is a white plastic screen, a gray plastic screen, a black grid screen, or a flexible PET (Polyethylene Terephthalate) composite film designed with a fresnel structure.

In order to connect the optical film 41 to the curling mechanism 2 and the lifting mechanism 3, the optical film 41 is large in size, which increases the cost. On the other hand, when the optical film 41 is used, the screen is displayed only in the irradiation area corresponding to the projection beam, and thus, in order to reduce the cost of the screen 4, the screen can be displayed by using the optical film 41 having a size as large as the irradiation area corresponding to the projection beam. Illustratively, the size of the optical membrane 41 is 1661 mm 934 mm.

In order to connect the curtain sheet 4 to the curling mechanism 2 and the lifting mechanism 3 and support the optical film 41, in another embodiment, as shown in fig. 3, the curtain sheet 4 includes an optical film 41 and a flexible carrier 42, a back surface of the optical film 41 is fixed on the flexible carrier 42, and a first side and a second side of the flexible carrier 42 are respectively fixedly connected to the curling mechanism 2 and the lifting mechanism 3.

The flexible carrier 42 is made of a material that is not easily deformed and has a high tensile strength, so as to ensure the curling of the flexible carrier 42 and avoid the deformation of the flexible carrier 42 under the action of an external force. Illustratively, the flexible carrier 42 is a synthetic fabric made of non-deformable polyester yarn with high tensile strength.

Here, the dimension of the optical film 41 in the length direction of the curling mechanism 2 is smaller than the dimension of the flexible carrier 42 in the length direction of the curling mechanism 2, that is, the width of the optical film 41 is smaller than the width of the flexible carrier 42. In this way, when the optical film 41 is bonded to the flexible carrier 42, the edge of the optical film 41 can be prevented from protruding from the flexible carrier 42, and the fixing efficiency of the optical film 41 can be improved.

Of course, as shown in fig. 3, the dimension of the optical film 41 in the length direction of the curling mechanism 2 may also be equal to the dimension of the flexible carrier 42 in the length direction of the curling mechanism 2, that is, the width of the optical film 41 is equal to the width of the flexible carrier 42. Thus, when the optical film 41 is fixed, the optical film 41 is conveniently aligned with the edge of the flexible carrier 42, so that the size of the curtain sheet 4 is reduced, and the display picture is paved on the whole curtain sheet 4, thereby improving the picture display effect of the curtain sheet 4.

In the embodiment of the application, when the lifting mechanism 3 cooperates with the curling mechanism 2 to cause the curtain sheet 4 to be unfolded, the left side and the right side of the curtain sheet 4 are not restricted, and at the moment, the curtain sheet 4 is easy to wrinkle and curl along the direction perpendicular to the left side due to self factors, so that the display picture on the curtain sheet 4 is deformed, and the display effect is poor. Therefore, as shown in fig. 1, after the curtain sheet 4 is unfolded, at least the part close to the third side edge and the part close to the fourth side edge are fixedly connected with the lifting mechanism 3, and the third side edge is opposite to the fourth side edge.

Wherein, the third side and the fourth side of the curtain sheet 4 are the left side and the right side of the curtain sheet 4. Like this, after curtain 4 expandes, through the fixed of the part that elevating system 3 was close to the third side at least to curtain 4 and the part that is close to the fourth side, can realize the restraint to the left and right sides limit of curtain 4 to avoid curtain 4 to take place the problem of fold and turn-up, and then avoided the problem that the display screen warp on curtain 4, improved display effect.

Optionally, the lifting mechanism 3 and the curtain sheet 4 may be fixed by magnetic attraction, or may be fixed by adhesion, specifically, the fixing manner is determined according to the specific structure of the lifting mechanism 3.

When the curtain sheet is fixed in a magnetic attraction mode, a magnetic coating can be sprayed, adhered and printed on the curtain sheet 4, or magnetic powder and the like are doped in the manufacturing process of the curtain sheet 4, and meanwhile, a metal piece is selected as the lifting mechanism 3, or a metal coating is arranged on the lifting mechanism 3, so that the curtain sheet 4 and the lifting mechanism 3 are fixed through the adsorption between the magnetic powder and the metal piece; metal powder can be sprayed, adhered and printed on the curtain sheet 4, or the metal powder is doped in the manufacturing process of the curtain sheet 4, and meanwhile, the magnetic part is selected as the lifting mechanism 3, or a magnetic coating is arranged on the lifting mechanism 3, so that the curtain sheet 4 and the lifting mechanism 3 are fixed through the adsorption between the metal powder and the magnetic part; of course, a magnetic coating may be sprayed, adhered, and printed on the curtain sheet 4, or magnetic powder may be doped during the manufacturing process of the curtain sheet 4, and the magnetic member may be selected as the lifting mechanism 3, or the magnetic coating may be disposed on the lifting mechanism 3, so as to fix the curtain sheet 4 and the lifting mechanism 3 by the adsorption between the magnetic member and the magnetic member.

In this application embodiment, after the curtain 4 expandes, can directly fix the part that the curtain 4 is close to the third side at least, the part that is close to the fourth side through first crane 31 is direct, certainly also can add other structures on first crane 31's basis, and then fix the part that the curtain 4 is close to the third side at least, the part that is close to the fourth side through other structures. Next, the fixing of the curtain sheet 4 will be explained in detail with reference to the specific structure of the elevating mechanism 3.

In the first case, as shown in fig. 1, the lifting mechanism 3 includes a first lifting frame 31, the first lifting frame 31 is formed with a first fixing portion and a second fixing portion after the curtain sheet 4 is unfolded, the portion of the back of the curtain sheet 4 close to the third side is fixed to the first fixing portion in an adsorption manner, and the portion of the back of the curtain sheet 4 close to the fourth side is fixed to the second fixing portion in an adsorption manner. In this way, the first fixing portion and the second fixing portion can fix the portion of the curtain sheet 4 close to the third side and the portion of the curtain sheet 4 close to the fourth side, that is, the left and right sides of the curtain sheet 4 are restrained.

Optionally, in combination with the fixing manner described above, a portion of the back surface of the curtain sheet 4 close to the third side edge and a portion of the back surface of the curtain sheet 4 close to the fourth side edge both have a magnetic coating, and the first fixing portion and the second fixing portion both have a metal coating, so as to fix the first fixing portion and the portion of the back surface of the curtain sheet 4 close to the third side edge, and fix the second fixing portion and the portion of the back surface of the curtain sheet 4 close to the fourth side edge.

Wherein, in order to guarantee the fixing effect of the first fixing part and the part of the curtain sheet 4 close to the third side and the fixing effect of the second fixing part and the part of the curtain sheet 4 close to the fourth side, the first lifting frame 31 is a folding lifting frame. So, the size of each connecting rod that adjustable first crane 31 includes for first crane 31 rises the back, and first fixed part and second fixed part all are the banding, and in order to guarantee that the part that the back of curtain 4 is close to the third side, the part that is close to the fourth side is whole to be fixed at first fixed part, second fixed part respectively.

Exemplarily, as shown in fig. 1, the first crane 31 includes a first folding rod 311, a second folding rod 312 (not shown), a first support rod 313 and a second support rod 314 (not shown), wherein both ends of the first folding rod 311 are rotatably connected to the base 1 and the cross beam 32, respectively, and both ends of the second folding rod 312 are rotatably connected to the base 1 and the cross beam 32, respectively; the base 1 has a guide rail 12, and a first slider 51 and a second slider 51 sliding along the guide rail 12, both ends of a first support rod 313 are respectively rotatably connected with the first folding rod 311 and the first slider 51, and both ends of a second support rod 314 are respectively rotatably connected with the second folding rod 312 and the second slider 51. Thus, when the first slider 51 and the second slider 51 are relatively separated from each other, the first support bar 313 and the second support bar 314 respectively support the first folding bar 311 and the second folding bar 312 such that the first folding bar 311 and the second folding bar 312 are both supported in a linear configuration. At this time, the first folding rod 311 near the screen 4 forms a first fixing portion, and the second folding rod 312 near the screen 4 forms a second fixing portion.

Because the first fixing portion and the second fixing portion are fixed to the screen 4 at the back of the screen 4, the aesthetic property of the projection screen is not affected, and therefore, a magnetic coating can be disposed on the entire back of the screen 4, or a plurality of strip-shaped magnetic coatings can be disposed on the back of the screen 4, as long as the back of the screen 4 can be fixedly connected to the first fixing portion and the second fixing portion. The plurality of strip-shaped magnetic coatings at least comprise magnetic coatings which are positioned at a part of the curtain sheet 4 close to the third side edge and a part of the curtain sheet 4 close to the fourth side edge, and the plurality of strip-shaped magnetic coatings have the same or not all the same width.

It should be noted that, after the curtain sheet 4 is unfolded, the first lifting frame 31 may form other fixing portions besides the first fixing portion and the second fixing portion, and further, the position corresponding to the back surface of the curtain sheet 4 is fixedly connected with the other formed fixing portions, and the fixing manner may refer to the above description.

In the second case, as shown in fig. 4, the lifting mechanism 3 further comprises a second lifting frame 33; the second crane 33 is limited on the base 1, the second crane 33 is connected with the cross beam 32, the second crane 33 is formed with a third fixing part and a fourth fixing part after the curtain sheet 4 is unfolded, the part of the front of the curtain sheet 4 close to the third side edge is fixedly adsorbed with the third fixing part, and the part of the front of the curtain sheet 4 close to the fourth side edge is fixedly adsorbed with the fourth fixing part.

Wherein, in order to ensure the fixing effect of the third fixing part and the part of the curtain sheet 4 which is close to the third side and the fixing effect of the fourth fixing part and the part of the curtain sheet 4 which is close to the fourth side, the second lifting frame 33 is a folding lifting frame. So, the size of each connecting rod that adjustable second crane 33 includes for second crane 33 rises the back, and third fixed part and fourth fixed part all are the banding, and in order to guarantee that the part that the curtain 4 openly is close to the third side, the part that is close to the fourth side is whole to be fixed at third fixed part, fourth fixed part respectively.

Illustratively, as shown in fig. 4, the second crane 33 includes a third folding bar 331 and a fourth folding bar 332, both ends of the third folding bar 331 are rotatably connected to the base 1 and the cross member 32, respectively, and both ends of the fourth folding bar 332 are rotatably connected to the base 1 and the cross member 32, respectively. Thus, when the first crane 31 is lifted, the third folding bar 331 and the fourth folding bar 332 are lifted up to be in a linear structure by the cross beam 32. At this time, the third folding bar 331 forms a third fixing portion on the side close to the screen sheet 4, and the fourth folding bar 332 forms a fourth fixing portion on the side close to the screen sheet 4.

Because the second crane 33 is located at one side of the front surface of the curtain sheet 4 after being lifted, at this time, in order to avoid the shielding of the second crane 33 on the curtain sheet 4, the second crane 33 only forms a third fixing part and a fourth fixing part which are respectively fixed with the part of the front surface of the curtain sheet 4 close to the third side edge and the part close to the fourth side edge. In addition, in order to avoid the third fixing portion and the fourth fixing portion from increasing the width of the projection screen, the width of the third fixing portion and the width of the fourth fixing portion may be adjusted to be equal to the width of the side of the non-display area on the screen 4.

Optionally, in combination with the fixing manner described above, a portion of the front surface of the curtain sheet 4 near the third side and a portion near the fourth side both have a magnetic coating, and the third fixing portion and the fourth fixing portion both have a metal coating, so as to fix the third fixing portion to the portion of the front surface of the curtain sheet 4 near the third side, and fix the fourth fixing portion to the portion of the front surface of the curtain sheet 4 near the fourth side. In combination with the above description, in order to ensure the connection stability of the curtain sheet 4 with the third fixing portion and the fourth fixing portion, a magnetic coating may be disposed on the entire side of the non-display area on the curtain sheet 4, so as to maximize the fixing area between the curtain sheet 4 and the first fixing portion and the second fixing portion.

In a third case, as shown in any one of fig. 5 to 9, the lifting mechanism 3 further includes a curling element 34, two ends of the curling element 34 are respectively and fixedly connected to the curling mechanism 2 and the cross beam 32, and at least a portion of the curtain sheet 4 close to the third side edge and a portion of the curtain sheet 4 close to the fourth side edge are fixedly connected to the curling element 34.

Since one end of the curling element 34 and the second side of the curtain sheet 4 are both fixedly connected to the cross beam 32, when the curtain sheet 4 is unfolded or folded, the curling element 34 and the curtain sheet 4 are lifted synchronously, and thus, in combination with the above-described fixing manner, the curling element 34 and the curtain sheet 4 are fixed by adhesion or by magnetic attraction. The curling piece 34 can be made of metal materials such as stainless steel and aluminum alloy, and can also be made of non-metal materials such as PET, polyimide, cloth and rubber, so long as the flatness of the manufactured curling piece 34 is superior to that of the curtain sheet 4.

Wherein, as shown in any one of fig. 5-8, the curling element 34 is fixedly connected with the curtain sheet 4 at the back of the curtain sheet 4, or as shown in fig. 9, the curling element 34 is fixedly connected with the curtain sheet 4 at the front of the curtain sheet 4.

When the curling element 34 is fixedly connected with the curtain sheet 4 at the back of the curtain sheet 4, optionally, as shown in fig. 5 or fig. 6, the curling element 34 is in a sheet structure, and the back of the curtain sheet 4 is fixedly connected with the curling element 34; alternatively, as shown in fig. 7 or 8, the curling element 34 is in a strip structure, and the curling element 34 is fixedly connected to at least a portion of the back surface of the curtain sheet 4 close to the third side edge and a portion close to the fourth side edge.

The curler 34 of the sheet structure can restrain the whole curtain sheet 4, thereby avoiding the problems of wrinkles and curling of the curtain sheet 4. A plurality of ribbon-like crimping elements 34 are evenly distributed along the length of the crimping mechanism 2.

When the curling elements 34 are fixedly connected with the curtain sheet 4 at the front surface of the curtain sheet 4, as shown in fig. 9, the curling elements 34 are in a strip-shaped structure, and two curling elements 34 are fixedly connected with a part of the front surface of the curtain sheet 4 close to the third side edge and a part of the front surface of the curtain sheet 4 close to the fourth side edge respectively. Therefore, the shielding of the two curlers 34 on the display picture on the screen 4 can be avoided, and the restriction on the left side and the right side of the screen 4 is realized.

It should be noted that the curling element 34 and the curtain sheet 4 can be fixed on the same roll, and the curling mechanism 2 includes, for example, one roll; of course, the crimper 34 and the curtain sheet 4 may be fixed on different reels, and the crimping mechanism 2 includes two reels, for example.

For the first and second cases described above, the first lifting frame 31 and the second lifting frame 33 are both folding lifting frames, and for example, the first lifting frame 31 needs to be fixedly connected to the back of the curtain sheet 4 after the first folding rod 311 and the second folding rod 312 included in the first lifting frame 31 are supported, so that the first lifting frame 31 can be continuously contacted with the back of the curtain sheet 4 when the first folding rod 311 and the second folding rod 312 are supported, so as to have a flattening operation from the center to the side of the curtain sheet 4, thereby further ensuring the flatness of the curtain sheet 4 after being unfolded.

The three cases described above explain two ways of fixing the screen sheet 4 on the back side of the screen sheet 4 and two ways of fixing the screen sheet 4 on the front side of the screen sheet 4, that is, fixing the screen sheet 4 only on one side (front side or back side) of the screen sheet 4. Of course, in order to ensure the restraining effect on the left and right sides of the screen 4, the screen 4 may be fixed on both sides (front and back) of the screen 4 at the same time, so as to increase the restraining force on the screen 4.

In an example, the two sides of the curtain sheet 4 are fixed by combining the first case and the second case, that is, as shown in fig. 10, the first fixing portion and the second fixing portion formed after the first lifting frame 31 is lifted respectively fix the portion of the back surface of the curtain sheet 4 close to the third side and the portion close to the fourth side, and the third fixing portion and the fourth fixing portion formed after the second lifting frame 33 is lifted respectively fix the portion of the front surface of the curtain sheet 4 close to the third side and the portion close to the fourth side.

In the second example, the two-sided fixation of the curtain sheet 4 is realized by the combination of the curler 34 and the front surface of the curtain sheet 4 in the first and third cases, that is, as shown in fig. 11, the first fixing part and the second fixing part formed by the lifting of the first lifting frame 31 fix the back surface of the curtain sheet 4 near the third side and the fourth side, respectively, and the two ribbon curlers 34 fix the front surface of the curtain sheet 4 near the third side and the fourth side, respectively.

In the third example, the two-sided fixation of the curtain sheet 4 is realized by the combination of the curler 34 and the back of the curtain sheet 4 in the second and third cases, that is, the third and fourth fixing parts formed by the second crane 33 lifting up fix the front of the curtain sheet 4 near the third side and near the fourth side, respectively, and the sheet-shaped curler 34 or the plurality of strip-shaped curlers 34 fix at least the back of the curtain sheet 4 near the third side and near the fourth side.

In the fourth example, the two-sided fixation of the curtain sheet 4 is achieved by combining the two manners in the third case, that is, as shown in fig. 12, the sheet-shaped curling element 34 or the plurality of strip-shaped curling elements 34 fix at least the portion of the back surface of the curtain sheet 4 near the third side and the portion near the fourth side, and simultaneously fix the portion of the front surface of the curtain sheet 4 near the third side and the portion near the fourth side by the two strip-shaped curling elements 34.

In the embodiment of the present application, for several fixing manners of the curtain sheet 4 described in the above embodiments, in order to ensure the fixing stability of the curtain sheet 4 and avoid the situation that the curtain sheet 4 is separated from the lifting mechanism 3, as shown in fig. 13, the projection screen further includes a pressing mechanism 5, the pressing mechanism 5 is limited on the base 1, the position of the pressing mechanism 5 in the length direction of the vertical curling mechanism 2 is adjustable, and the pressing mechanism 5 is in contact with the curtain sheet 4 or in contact with the curling element 34. Like this, with the back of curtain 4 and the first fixed part, the fixed example of second fixed part of first crane 31, hold-down mechanism 5 compresses tightly the one side of keeping away from first crane 31 on curtain 4 to reduce the distance between curtain 4 and first fixed part, the second fixed part, thereby increase the steadiness of being connected between the back of curtain 4 and first fixed part, the second fixed part.

Alternatively, as shown in fig. 13, the pressing mechanism 5 includes a slider 51, an adjusting screw and a pressing roller 53, the base 1 has a protrusion 11 and a guide rail 12, the slider 51 is slidably limited on the guide rail 12, the adjusting screw is respectively connected with the protrusion 11 and the slider 51, the adjusting screw is used for adjusting the distance between the protrusion 11 and the slider 51, the end of the pressing roller 53 is fixedly connected with the slider 51, and the pressing roller 53 is in contact with the curtain sheet 4 or the curler 34. Thus, when the pressing force of the pressing roller 53 on the curtain sheet 4 or the curling element 34 needs to be adjusted, only the adjusting screw 52 needs to be rotated to cause the sliding block 51 to slide along the guide rail 12, and then the pressing roller 53 is driven to move along the guide rail 12.

The length direction of the guide rail 12 is perpendicular to the plane where the first lifting frame 31 is located when being lifted, that is, the included angle between the length direction of the guide rail 12 and the plane where the first lifting frame 31 is located when being lifted is 90 degrees. Of course, the included angle between the length direction of the guide rail 12 and the plane where the first lifting and lowering operation is performed may also be 88 degrees, 92 degrees, and the like, which is not limited in the embodiment of the present application.

In the embodiment of this application, one of the first crane, the second crane, the piece that curls that includes through elevating system after the curtain piece expandes, perhaps both arbitrary are fixed the part that the curtain piece is close to the third side at least, the part that is close to the fourth side, can realize the restraint to the left and right sides limit of curtain piece, thereby avoid the curtain piece to take place the problem of fold and turn-up, and then avoided the problem that the display screen warp on the curtain piece, improved display effect.

The above description is only illustrative of the embodiments of the present application and is not intended to limit the embodiments of the present application, and any modification, equivalent replacement, or improvement made within the spirit and principle of the embodiments of the present application should be included in the scope of the embodiments of the present application.

Claims

1. A projection screen, comprising: the device comprises a base, a curling mechanism, a lifting mechanism and a curtain sheet;

the curling mechanism and the lifting mechanism are limited on the base;

2. The projection screen of claim 1 wherein the lift mechanism comprises a first lift and a cross beam;

the first lifting frame is limited on the base, the first lifting frame is connected with the cross beam, and the second side edge of the curtain sheet is fixedly connected with the cross beam;

after the curtain piece expandes first crane is formed with first fixed part and second fixed part, the back of curtain piece be close to the part of third side with first fixed part adsorbs fixedly, the back of curtain piece be close to the part of fourth side with the second fixed part adsorbs fixedly.

3. The projection screen of claim 2 wherein a portion of the back of the curtain sheet proximate the third side and a portion proximate the fourth side each have a magnetic coating and the first anchor and the second anchor each have a metal coating.

4. A projection screen according to claim 2 or 3 wherein the lifting mechanism further comprises a second lifting frame;

the second crane is spacing on the base, the second crane with the crossbeam is connected, the curtain piece expandes the back the second crane is formed with third fixed part and fourth fixed part, the front of curtain piece be close to the part of third side with the third fixed part adsorbs fixedly, the front of curtain piece be close to the part of fourth side with the fourth fixed part adsorbs fixedly.

5. The projection screen of claim 1 wherein the lift mechanism comprises a first lift, a cross beam, and a curl;

the two ends of the curling piece are respectively fixedly connected with the curling mechanism and the cross beam, and the curtain sheet is at least close to the part of the third side edge and the part of the fourth side edge and is fixedly connected with the curling piece.

6. The projection screen of claim 5 wherein the curling element is in the form of a sheet and the back of the screen is fixedly attached to the curling element; alternatively, the first and second electrodes may be,

the curling piece is in a strip-shaped structure, and the curling piece is fixedly connected with at least the part of the back of the curtain sheet close to the third side edge and the part of the back of the curtain sheet close to the fourth side edge.

7. A projection screen according to claim 6 wherein a plurality of said ribbon-like curling elements are evenly distributed along the length of said curling mechanism.

8. The projection screen of claim 6 or 7, wherein the elevating mechanism further comprises a second elevating frame;

9. The projection screen of claim 5 wherein the plurality of rolling members are in a strip configuration and wherein two of the plurality of rolling members are fixedly attached to the front of the screen adjacent the third side and the fourth side, respectively.

10. The projection screen of claim 9, wherein the first crane is formed with a first fixing portion and a second fixing portion after the screen sheet is unfolded, a portion of the back of the screen sheet near the third side edge is fixedly attached to the first fixing portion, and a portion of the back of the screen sheet near the fourth side edge is fixedly attached to the second fixing portion.

11. A projection screen according to any one of claims 5 to 7 and 9 to 10 wherein the curler is adhesively or suction secured to the screen sheet.