JPH099184A - Multi-vision - Google Patents

Abstract

PURPOSE: To improve the mobility, expansion performance, and maintenance performance by mounting a projection unit to a long member whose forward 7 backward direction is used for its lengthwise direction and supporting the long member in a moving/stop enable way. CONSTITUTION: Core units 1 are stacked horizontally and vertically while arranging the front face of each screen 9 of each unit 1, and the core unit 1 is roughly made up of a screen unit 2, a a projection unit 3, and a frame 5 mounting the projection unit 3, and an attachment/detachment frame 13 linking the frame 5 and the screen unit 2 removably. Four sides of the screen 9 of the screen unit 2 are locked by a screen frame 10 to provide one of an elastic removable block 30 and the other for the screen frame. The projection unit 3 is made up of a set 33 of a projector and a lens and a heat sink 34 and mounted on a support rail 24 engaging with a turning rail 25 via a rotary shaft 28 and a ray of a video image of the projection unit 3 is projected to a back side of the screen 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to multivision in consideration of mobility, expandability and maintainability.

[0002]

2. Description of the Related Art A core unit stacking type multi-vision system has a projection unit consisting of a projection device and a lens, and a screen unit set for projecting an image of the projection unit covered by a housing so that the front of the core unit is aligned. It is formed by combining the top and bottom. As an example of this kind of multi-vision, there is a projection image device and an assembling device disclosed in JP-A-4-113789.

[0003]

Problems to be Solved by the Invention
In the example disclosed in Publication No. 9, according to the desire of the supplier side, the number of stacking units in core units and the number of rows arranged in core unit units are selected so as to fit in the space of the installation site. It has the feature that it can be installed in different installation spaces. In addition, since core units can be stacked and unloaded, there is a feature that installation and removal can be done in a short time. However, in this example, there is no description about ease of assembly and removal, reinforcement of multi-vision with different number of stacks, adjustment and replacement of the projection unit inside the housing with multiple core units installed, and mobility and expandability. , No consideration was given to maintainability. An object of the present invention is to provide a multi-vision structure having good mobility, expandability, and maintainability while taking advantage of the features of the core unit type multi-vision.

[0004]

In order to achieve the above object, the present invention adopts the following multi-vision structure.

(1) The projection unit is mounted on a long piece member whose longitudinal direction is the longitudinal direction, and the long piece member is supported so as to be movable and stoppable.

(2) A member in which a projection unit is mounted and a pedestal forming the outer shape of the core unit is formed by joining a plurality of long piece members at right angles to each other, and two orthogonal long piece members are specially provided. It was fixed by inclining with respect to the orthogonal direction.

(3) The fixed shape of the signal input portion of the chassis portion of the projection unit is formed so that the signal input portion of the projection unit can be exchangeably fixed to the front surface and the rear surface.

(4) The screen unit is engaged with the core unit by the elastic attachment / detachment means, and the pin is engaged with the groove so that the screen unit is coupled with the core unit. The removal core unit was provided with a mechanism for removing the screen unit.

(5) The frame for mounting the projection unit is formed of a long piece member to have a frame structure.

(6) A pair of corner portions of the pedestal or the core unit are defined, and a pair of other corner portions are recessed to form a pair of upper and lower grooves, and the adjacent corner portions of the horizontally adjacent core units. Then, the recessed corners were fixed together by fasteners, and the four core units were joined at the same time.

(7) The pedestal and the screen unit are detachably attached, and only an arbitrary set is connected by a rotatable detachable frame.

[0012]

[Action]

(1) Since the projection unit movably supports the long piece member, it can be pulled out to the front and rear surfaces.

(2) Since the two long strip members that are orthogonal to each other are fixed to the mount by inclining with respect to the orthogonal direction by a special member, the joint strength against the bending moment of the joint portion is remarkably increased.

(3) Since the signal input portion of the projection unit can be exchangeably fixed to the front surface and the rear surface, adjustment and maintenance of the projection unit can be performed from the front and rear surfaces.

(4) Since there is provided a mechanism for manually removing the connection of the groove from the front surface and removing the screen unit from the core unit, internal adjustment, maintenance and replacement of the projection unit can be performed from the front surface.

(5) Since the pedestal for mounting the projection unit is formed of a long piece member and has a frame structure, the long piece member can be maintained as a multi-vision, and maintenance can be performed from the rear surface after climbing with human hands and feet. become able to.

(6) Since four core units can be joined at the same time, the time required for assembly and removal can be significantly shortened.

(7) Attaching and detaching the frame and the screen unit,
Since it is possible to connect only an arbitrary set of rotatable detachable frames, it is possible to increase the number of detachable frames according to the number of stacked core units and ensure seismic strength.

[0019]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a core unit according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA of FIG.

In each drawing, 1 is a core unit, 2 is a screen unit, 3 is a projection unit, 5 is a pedestal, 9 is a screen, 10 is a screen frame, 12 is a screen frame, 13 is a removable frame, and 15 is a square tube. , 16 is an upper connecting frame, 18 is a lower connecting frame, 24 is a support rail, and 25 is a rotating rail.

26 is a bottom plate, 27 is a top plate, 28 is a rotary shaft,
31 is a light-shielding plate, 33 is a set of lenses, 34 is a heat dissipation plate, 36
Is a first wing bolt, 37 is a second wing bolt, and 40 is a roller.

1 and 2, the multi-vision of the present invention is such that the front surface of the screen 9 of the core unit 1 is aligned and stacked vertically and vertically, and the core unit 1 roughly includes the screen unit 2, the projection unit 3 and the projection unit 3. And a detachable frame 13 that detachably connects the pedestal 5 and the screen unit 2. Screen unit 2
Has four sides of the screen 9 locked by the screen frame 10, one of the elastic attachment / detachment blocks 30 and the other of the screen frame, and the projection unit 3 includes a projection device, a set of lenses 33, and a heat dissipation plate 34. It is mounted on the support rail 24 that engages with the rotary rail 25 via the rotary shaft 28, and projects the light beam of the image of the projection unit 3 on the back surface of the screen 9. The pedestal 5 is formed by making a plurality of square tubes 15 orthogonal to each other and joining them together.
The upper part is connected to the upper connecting frame 16 and the lower part is fixed to the lower connecting frame 18 with their outer shapes inclined with respect to the direction orthogonal to each other.
The support rail 24 is supported, the support rail 24 is fixed to the square tube 15 by a second butterfly bolt 37, and the rotating rail 25 is fixed to the screen frame 12 by a first bolt 36.
The end portions of the detachable frames 13 are connected to the connection frames 15 and 1, respectively.
6 and the screen frame 12 are detachably connected with a mechanical screw or the like.

A method of maintaining multi-vision having this configuration will be described.

In FIG. 1 and FIG. 2, the screen unit 2 is removed from the front side of the lower core unit (details of concrete means for locking the screen unit will be described in the third embodiment). 2, the second butterfly bolt 37 shown in FIG. 2 is previously removed at the time of installation, the first butterfly bolt 36 is loosened, and the rotary rail 25 is pulled forward, so that the projection unit 3 mounted on the support rail 24 can be mounted. The projection unit 3 in the core unit is moved forward and manually adjusted and replaced for maintenance from the front. It becomes an indispensable means when the maintenance space cannot be maintained on the rear surface or inside the core unit 1 depending on the installation location.

Next, a structure for maintaining the inside of the core unit 1 from the rear surface of the core unit 1 will be described. (Details of the specific structure of the core unit will be described in the fourth embodiment.) The first wing bolt 36 is removed in advance during installation, the second wing bolt 37 is loosened, and the support rail 24 is pulled rearward. Allows the projection unit 3 mounted on the support rail 24 to
Is moved rearward, and maintenance and maintenance such as adjustment and replacement of the projection unit 3 in the core unit 1 is manually performed from the rear side. It becomes an indispensable means when the maintenance space cannot be secured on the front surface or inside the core unit 1 depending on the installation location.

Next, a structure for entering the space between the multi-vision screen unit 2 and the projection unit 3 and performing internal maintenance will be described.

The detachable frame 13 is removed so that the detachable frame 10, the side plate 21, and the top plate 25 are provided only on the outer surface of the core unit 1 located at the outermost portion so as to shield the light from the outside, and each support rail 24 is rotated by the rotary shaft 28. And fold it back and fold it and fix it in the screw hole 29 with the first wing bolt 36, continuously form an intermediate space between each screen unit 2 and the projection unit 3, and enter the space formed in the middle to enter the internal space. Maintenance Perform maintenance. This is an indispensable measure when maintenance space cannot be secured on the front and rear sides depending on the installation location.

According to this embodiment, a multi-vision structure in which a maintenance space is provided on either the front surface or the rear surface can be selected without changing the main components of the screen unit 2, the projection unit 3, and the gantry 5.

The weight saving of the multi-vision having the above structure will be described.

In FIGS. 1 and 2, the gantry 5 is formed by orthogonally connecting a plurality of square tubes 15 to each other, and the gantry 5 is formed by making a plurality of square tubes 15 orthogonal to each other and joining them.
Since the upper part of each of them is fixed to the upper connecting frame 16 and the lower part of the lower connecting frame 18 is slanted with respect to the direction orthogonal to each other, the rectangular pipe 15 is not subjected to a vertical load when a horizontal vibration is applied. Joining, connecting frames 16, 18
Since a bending moment is generated, the square tube 15 is made of a material having a relatively small allowable volume and a large volume, and the connecting frames 16 and 18 are made of a material having a relatively large allowable load. As a result, the weight of the gantry 5 can be reduced while maintaining rigidity and strength, and the gantry 5 itself has a frame structure to form the projection unit 3 lens set 33.
Since the back surface of the screen 9 is shielded by the light shielding member, the weight can be further reduced as compared with the conventional core unit having a structure in which the frame is shielded.

Next, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 3 shows an explanatory view of the projection unit shown in FIG. Reference numeral 45 is an input / output unit, 47 is a code, 48 is a connector, 50 is an input / output terminal, and 53 is a board fixing screw.

Signals from the input / output unit 45 for inputting / outputting image resources and control signals to / from the projection unit 3, a cord 47 for supplying electric power, a connector 48, and a set screw 53 are provided at the same position and the input / output terminal section 50 is provided. The input / output unit 45 is arranged on the front surface, inverted around the cord 47 or the connector 48 portion and arranged so that the input / output terminal portion 50 is arranged on the rear surface (shown by a broken line), and the input / output unit 45 is selected on the rear surface or the front surface. When the projection unit 3 is replaced from the front side and the inside and when it is replaced from the rear side, the projection unit 3 can be easily replaced and wired.

Next, a third embodiment of the present invention will be described.

4 and 5 are enlarged views of the screen unit shown in FIG. 2, in which 77 is a screen bracket and 79 is a screen bracket.
Indicates a pin provided on the screen bracket 77,
80 is a link, 82 is a long hole provided in the link 80, 8
3 is a stepped screw provided on the screen bracket 77, 84 is a light shielding plate provided on the link 80, 85 is a coil spring, and 86 is a hole provided on the screen frame 10. 91 is a screen frame, 92 is a screen unit, 97 is a notch provided on the screen bracket 77, 102 is a hook part provided on the screen frame 91, 110 is a wire spring, and 111 is a screw with a washer. .

In FIG. 4, the screen unit 2 has a screen 9 surrounded by a screen frame 10 all around.
The elastic attachment / detachment block 30 provided in 0 removably engages with the screen bracket 77, and the link 80 can move vertically due to the engagement of the slot 82 and the stepped screw 83. The pin 9 is engaged with the hook portion 81 of the link 80 to maintain its position while being pressed, and the light shielding plate 84 below the link 80 closes the hole 86. The operation of removing the screen unit 2 of this configuration from the screen bracket 77 will be described below.
When the light shielding plate 84 is pushed upward (arrow in the figure) from the hole 86 by a person's hand, the link 80 rises, the hook portion is separated from the pin 79, and the pin 79 is released. In this state, by pulling the screen unit 2 to the front (to the left in the figure), the screen bracket 77 is separated from the screen bracket 77 at the elastic removable block 30. With the screen unit 2 and the screen bracket 77 of this structure stacked as a multi-vision, the hole 86 is opened and the core unit 5 located at the lowest stage in contact with the gantry is detached, and the core unit 1 at the upper stage is sequentially arranged. The screen unit 2 can be removed from the front side without worrying about increasing the joint width, because there is no mechanism for removing the screen unit 2 in the vicinity of being in direct contact with the screen 9.

In FIG. 5, the screen unit 92 is detachably engaged with the screen bracket 77 through the detachable block 30, and the hook portion 102 provided on the screen frame 91 is fixed to the screen bracket 77 with the screw 111 having a washer. The fixed wire spring 110 is fixed by engaging the wire spring 110. In the state where the screen unit 92 and the screen bracket 77 having this configuration are stacked as a multi-vision, the notch 97 is opened and removed from the core unit located at the lowest stage in contact with the mount, as in the previous example (example of FIG. 4). This is a method of sequentially removing the screen unit 92 of the core unit 1 in the upper stage, and since there is no mechanism for removing the screen unit 2 near the direct contact with the screen 9, there is no fear of increasing the joint width and the screen unit 2 is in front. It can be removed from the direction.

Next, a fourth embodiment of the present invention will be described with reference to the drawings.

FIG. 6 is a side view of a multi-vision system in which the front surfaces of the core units shown in FIGS. 1 and 2 are aligned and stacked vertically and left and right. FIG. 7 shows the front surface of the core units shown in FIGS. FIG. 8 shows a rear view of a multi-vision device which is vertically and vertically stacked, and FIG. 8 shows an enlarged view of a portion B of FIG. 111 is a stand, 112 is an I bolt, and 121 is a set of bolts and nuts.

In FIG. 6 and FIG. 7, the core units 1 are stacked in three rows in the upward direction and three rows in the horizontal direction with their front surfaces aligned, and the upper connecting frame 16 and the lower connecting frame 18 provided at the four corners of the frame 5 are arranged. The upper and lower core units 1 and the left and right core units 1 are connected to each other by connecting with a set 121 of a bolt and a nut. In the case of performing maintenance from the rear surface (rear surface) of the multi-vision in the same figure, a person's limbs are put on the square tube 15 forming the pedestal 5 to climb up, and the projection unit 3 of the corresponding core unit is replaced and adjusted.

In FIG. 8, when the projection unit 3 is exchanged and adjusted, a lifeline is connected to the I-bolt 112 provided on the pedestal 5, and a means for protecting an operator who holds his / her limbs on the square tube 15 can also be taken. it can.

Next, a fifth embodiment of the present invention will be described with reference to the drawings.

FIG. 9 shows a cross-sectional view of the core unit shown in FIGS. 1 and 2 cut in the middle of a projection unit and a multivision screen unit 2 in which a plurality of front surfaces are aligned and stacked vertically and horizontally. 11 is an enlarged view of the C portion of FIG. 11 from the side, FIG. 11 is a perspective view showing an application example of the gantry shown in FIG. 9, and FIG. 12 is a front view of the application example of FIG.
FIG. 13 shows an enlarged view of part D in FIG. Reference numeral 125 represents a mount, 122 is a vertical frame, 123 is a horizontal frame,
127 is a front frame, 128 is a rear frame, 130
Indicates a coupling hole.

In FIG. 9, the upper end connecting frame 16 on the left end of the pedestal 5 of each core unit 1 and the upper connecting frame 16 on the right end of the pedestal 5 that is on the left side are combined to form a core located in the upper stage. The lower connecting frames 18 at the left end and the right end of the gantry 5 of the unit 1 are connected by a pair of scissors bolts and nuts 121, and the ends of the gantry 5 of four core units adjacent to each other vertically and horizontally except the outer periphery are joined by one bolt. And the set 121 of nuts are fastened, and the number of steps for assembling the core unit 1 is significantly reduced. In addition, the detachable frame 13 that connects the screen units 2 and 92 and the gantry 5 to the set of bolts and nuts 121 may be provided at an arbitrary position in order to secure strength according to the number of stacking stages of the core unit 1.

In FIG. 10, the upper connecting frame 16 and the lower connecting frame 18 are fastened to the joint portion of the square tube 15 of the gantry 5 with a set of bolts and nuts to join the square tubes, and the detachable frame 13 is also a set of bolts and nuts. At 121, it is detachably fixed to the upper connection frame 16 or the lower connection frame 18.

In FIG. 11, a frame 5 consisting of the square tube 15, the upper connecting frame 16 and the lower connecting frame 18 of FIGS. 6 and 7 is formed into left and right sides of the top and bottom having the same L-shaped cross section. The horizontal frame 123, the front frame 127 that forms the upper and lower sides of the front surface, the rear frame 128 that forms the upper and lower sides of the rear surface, and the vertical frame 122 that forms the upper and lower sides of the four corners are fixed. Then, the frame of the pedestal 125 is configured. Among them, the vertical frame 122 is shifted in parallel in the upward direction, and the upper end face is formed in the coupling hole 130 in the special thickness direction.
The horizontal frame 123 is positioned on the side surface at the lower end, and both end surfaces having the coupling hole 130 are arranged to be lowered to the inner side surface by the thickness of the vertical frame 122.

In FIG. 12 and FIG. 13, a plurality of pedestals 125 stacked vertically and horizontally are joined together by the connecting holes 130 of the vertical frames 122 of the adjacent pedestals 125, and the connecting holes of the horizontal frame 123 of the pedestal 125 located in the upper stage. The horizontal frame 123 of the pedestal 125 located on the upper side is also combined with 130.
The connecting holes 130 of the above are also combined and fastened to each of the connecting holes 130 with a set 121 of a bolt and a nut. Stand 1
Twenty-five horizontal frames 123 are fastened. The vertical frame 122 on the left side of the gantry 125 located at the left end is fastened to the coupling hole 130 of the horizontal frame 123 of the gantry 125 located at the upper stage with a bolt-nut set 121. Due to this combined state, the core unit 1 is stacked in three rows on the left and right and three stages on the top and bottom
Since the front surface of can be connected with a set of only 12 bolts and nuts, the number of connecting points is reduced and the installation and removal time is reduced.

Next, a sixth embodiment of the present invention will be described with reference to the drawings.

14 and 15 are sectional views of a multi-vision system in which the core units 1 shown in FIGS. 1 and 2 are stacked.

Reference numeral 135 denotes an integral side plate, and 135 denotes an integral side plate.

In FIG. 14, the detachable frame 13 which is provided with the front surface of the core unit 1 and is stacked in three rows vertically and in four rows, connects the gantry 5 and the screen unit 2 (not shown), and leaves the outer periphery and the lowermost layer. Removed, the side is an integrated side plate 135,
The top surface is covered with an integral top plate 137. At this time, the detachable frame 13 may be increased in number and installed depending on the installation posture such as inclination in consideration of the strength in the front-rear direction, and is used as a winch arm for lifting the projection unit (not shown) at the time of replacement. You may lay it.

In FIG. 15, the front and rear surfaces of the core unit 1 are aligned and stacked in six rows in the left and right, and six layers are vertically stacked. The detachable frame 13 for connecting the pedestal 5 and the screen unit 2 (not shown) is left with the outer periphery and the lowermost layer. Removed, the side is an integrated side plate 135,
The top surface is covered with an integral top plate 137. At this time, the detachable frame 13 may be increased in number and installed depending on the installation posture such as inclination in consideration of the strength in the front-rear direction, and is used as a winch arm for lifting the projection unit (not shown) at the time of replacement. You may lay it.

[0054]

According to the present invention, the following effects can be obtained.

(1) Since the projection unit can be pulled out to the front and rear surfaces, the exchangeability of the projection unit can be improved.

(2) Since the joint strength against the bending moment of the gantry joint portion is remarkably increased, the weight of the gantry can be remarkably reduced.

(3) Since the signal input portion of the projection unit can be exchangeably fixed to the front surface and the rear surface, adjustment and maintenance of the projection unit can be performed from the front and rear surfaces.

(4) Since a mechanism for removing the screen unit from the front surface is provided, internal adjustment, maintenance, and replacement of the projection unit can be performed more easily than the front surface.

(5) Since the multi-vision can be safely climbed from the rear surface, internal adjustment, maintenance, and replacement of the projection unit can be easily performed from the rear surface.

(6) Since four core units can be joined at the same time, the time required for assembly and removal can be shortened significantly.

(7) Since the pedestal and the screen unit can be connected by an arbitrary number of detachable frames, the number of detachable frames can be increased according to the number of stacked core units and seismic resistance can be secured without adding other parts.

[Brief description of drawings]

FIG. 1 is an external perspective view of a core unit according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is an explanatory view of the projection unit shown in FIG.

FIG. 4 is an enlarged view of the screen unit shown in FIG.

5 is an enlarged view of the screen unit shown in FIG.

FIG. 6 is a side view of a multi-vision in which a plurality of core units shown in FIGS. 1 and 2 are aligned in the front surface and stacked vertically.

FIG. 7 is a rear view of a multi-vision system in which a plurality of core units shown in FIGS. 1 and 2 are aligned in front and are stacked vertically and horizontally.

FIG. 8 is an enlarged view of part B in FIG.

FIG. 9 is a cross-sectional view of a multi-vision system in which a plurality of core units shown in FIGS. 1 and 2 are stacked.

FIG. 10 is an enlarged view of part C of FIG. 9 as viewed from the side.

FIG. 11 is a perspective view showing an application example of FIG.

FIG. 12 is a front view showing an application example of FIG.

13 is a perspective view showing an application example of FIG.

FIG. 14 is a cross-sectional view of multi-vision in which the core units shown in FIGS. 1 and 2 are stacked.

FIG. 15 is a cross-sectional view of multi-vision in which the core units shown in FIGS. 1 and 2 are stacked.

[Explanation of symbols]

 1 ... Core unit, 2 ... Screen unit, 3 ... Projection unit, 5 ... Frame, 9 ... Screen, 12 ... Screen frame, 13 ... Detachable frame, 15 ... Square tube, 16 ... Upper connecting frame, 18 ... Lower connecting frame, 24 ... Support rails, 25 ... Rotating rails.

Front page continuation (72) Fumihito Ichikawa, Inventor, Hitachi Image Information System, 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture (72) Hideo Misono, 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture Hitachi Information (72) Inventor Takashi Kambara, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Stock Company, Hitachi Ltd.

Claims (8)

[Claims] 1. A projection unit including a projection unit and a lens, and a core unit including a set of screen units for projecting image light of the projection unit, wherein the projection unit has a longitudinal direction in a longitudinal direction. A multi-vision system characterized by being mounted on a long piece member and supporting the long piece member so that the long piece member can be moved and stopped. 2. A projection unit comprising a projection device and a lens, and a core unit consisting of a screen unit for projecting the image light of the projection unit, wherein the projection unit is mounted and the core unit is mounted. A frame that forms the outer shape is formed by joining a plurality of long piece members at right angles to each other to form a housing, and the two long piece members that are orthogonal to each other are fixed by inclining them with respect to the orthogonal direction by a special member. Is a multi-vision. 3. A projection unit including a projection device and a lens, and a core unit including a screen unit for projecting image light of the projection unit, wherein a signal input portion of the projection unit includes a front surface and a rear surface. A multi-vision system characterized in that a fixed shape of the signal input section is formed on a chassis section of the projection unit so as to be exchangeably fixed. 4. An elastic attachment / detachment means for attaching the screen unit to the core unit, comprising a projection unit formed of a set of a projection device and a lens, and a core unit formed of a set of screen units for projecting image light of the projection unit. The screen unit and the core unit are joined by engaging the pin with the groove, and the pin is manually detached from the front face to remove the screen unit from the core unit. Multi vision. 5. A projection unit including a projection device and a lens, and a core unit including a screen unit for projecting image light of the projection unit, wherein a mount for mounting the projection unit is a long piece member. Multivision characterized by being formed into a frame structure. 6. The multi-vision system according to claim 1, 2, 3 or 4, wherein the front surfaces of the screen units are aligned and a plurality of core units are stacked vertically and horizontally. 7. A projection unit comprising a projection device and a lens, a frame for accommodating the projection unit, and a core unit comprising a screen unit for projecting image light of the projection unit. Align the fronts and stack them in the upper, lower, left, and right directions to identify the corners of the four corners of the pedestal or the core unit, and form them in a shape that overlaps each other. Multi-vision, which is fixed and has four core units connected at the same time. 8. A projection unit comprising a projection device and a set of lenses, a cradle for accommodating the projection unit, and a core unit made up of a set of screen units for projecting image light of the projection unit, the core unit comprising: A multi-vision system characterized in that a plurality of front and rear panels are stacked vertically, left and right, top and bottom, and the frame and the screen unit are attached and detached, and an arbitrary combination and a desired number are connected by a rotatable frame.