Abstract: An apparatus for cutting a sheet stack is provided. The sheet stack is composed of a plurality of sheets. The apparatus includes a cutting blade having a plate form and having a cutting edge at one side extending along a cutting width direction. The cutting blade has at the one side: a plurality of projecting blade portions having ridge lines forming edge lines capable of thrusting and sawing cutting, the projecting blade portions projecting in a cutting direction; and a straight bottom portion between adjacent projecting blade portions. Cutting of the sheet stack is performed by applying a load to the cutting blade in the cutting direction, and by reciprocating the cutting blade along the cutting width direction.

Abstract: A clip provided by the present invention includes an insert portion that is inserted into an insertion hole formed in a flat-shaped chassis and that engages with the chassis, and a collar portion that is formed in a flat shape around the circumference of the insert portion. When the insert portion is inserted into the insertion hole, the collar portion and the chassis clamp at least one light emitting board that is positioned in contact with the chassis, and the thickness of the collar portion is set to be equal to or less than an amount of protrusion of a light emitting portion formed protrudingly from the light emitting board.

Abstract: A clip provided by the present invention includes an insert portion that is inserted into an insertion hole formed in a flat-shaped chassis and that engages with the chassis, and a collar portion that is formed in a flat shape around the circumference of the insert portion. When the insert portion is inserted into the insertion hole, the collar portion and the chassis clamp at least one light emitting board that is positioned in contact with the chassis, and the thickness of the collar portion is set to be equal to or less than an amount of protrusion of a light emitting portion formed protrudingly from the light emitting board.

Abstract: In a projection apparatus projecting an image by using light of a light source contained in a housing, there is provided a light source mounting device in which when the light source in the housing is replaced, the light source is mounted and the light source is raised from a position of an opening used for taking in and out a light source to a normal position to make positioning, so that the light source in the housing can be simply replaced.

Abstract: A display apparatus and its cooling method in which the optical assemblies can be prevented from being smudged by dust entered into the apparatus so that an excellent image can be obtained and the apparatus can be cooled sufficiently with the apparatus including a housing having a screen on its front surface and a closed structure, an optical block having a closed structure and coupled with the housing in a closed fashion allowing air to circulate between the housing and the optical block. Further, the display apparatus includes a light source, a first cooling device for cooling the light source and a second cooling device for cooling the optical block. At least the optical block is arranged to have a closed structure and is cooled by air circulation.

Abstract: In a display unit wherein an optical block is disposed inside of a housing having a screen at its front, and an image light from the optical block is projected on the screen, a display unit in which the housing is made a closed structure and a path is provided for circulating air between the housing and the optical block so that dust is prevented from entering inside of an apparatus and attaching to optical parts, and at the same time, heat generated in the apparatus can be sufficiently cooled.

Abstract: The apparatus for punching a sheet S includes a shaft 2 extending transversely relative to the moving direction of the sheet S; a pair of cams 3, 3 mounted to the shaft 2 in both longitudinal end portions for rotating together with the shaft 2; a tie bar 4 extending along the shaft 2 and having a pair of cam followers 41, 41 at positions corresponding to those of the cams 3, 3; a plurality of punches 5, 5 connected to the tie bar 4 in longitudinal arrangement for being movable to and from punching positions; a frame 7 extending along the tie bar 4, to which a plurality of punch guides 6, 6 are fixed in alignment with the punches 5, 5; and a die frame 8 having a plurality of die holes 81, 81 in alignment with the punches 5, 5 for cooperating with the punches 5, 5 to make holes in the sheet S.