the present invention will now be described in reference to the attached drawings . in reference to fig1 and 2 , the electric press of the invention has an airtight casing a covering the upper essential parts of the electric press and a lower working bed 3 . the casing a is composed of a head 1 and a column 2 extending from the head 1 to the working bed 3 for supporting thereon a work to be pressed . the head 1 has an operation board ( though not shown ) provided on the front side thereof . the joint between the head 1 and the column 2 is sealed to be substantially airtight . the working bed 3 has a controller 4 provided on the front side thereof . the column 2 of the casing a has the lower end fixedly connected to the upper surface of the working bed 3 and sealed to be airtight . in any case , the casing a must be airtight even if the casing is composed of more than the head 1 and the column 2 . in the casing a there are provided a drive part 5 , a transmission part 6 , a pressing part 7 and a control part 8 which are all movable with their own functions . more particularly , the drive part 5 includes an electric motor . the transmission part 6 is arranged between the drive part 5 and the pressing part 7 and includes pulleys 6 a and a transmission belt 6 b extended around the pulleys 6 a . the pressing part 7 is substantially composed of a ram 7 a and a ram driving member 7 b which is operated to move the ram 7 a vertically of a work ( not shown ) placed on the working bed 3 to be pressed . the ram driving member 7 b is of a cylindrical structure in which an elongated threaded member is rotated with ball bearings to vertically move the ram 7 a with a stroke s relative to a work placed on the working bed 3 to be pressed by the ram 7 a . the ram 7 a is axially covered with a vertically flexible dust boot 14 . the dust boot 14 has the upper end sealingly connected to the lower end of the head 1 of the casing a and has the lower end sealingly connected to the lower part of the ram 7 a such that the dust boot 14 may be vertically flexible with the vertical movements of the ram 7 a , thereby to prevent the dusts from coming out of the casing a while the ram is vertically moved . a dust absorbing pipe 10 is provided in the casing a . the dust absorbing pipe partly extends along a route adjacent to the moving vibration and / or impact generating elements including the drive part 5 , the transmission part 6 and the work pressing part 7 . as shown in fig3 the dust absorbing pipe 10 includes a dust guiding portion 10 a and a dust absorbing portion 10 b and is made of the materials including a metal such as a stainless steel and a synthetic resin such as silicon gum . particularly the dust absorbing portion 10 b is extended along the entire route around and adjacent to the moving and vibration and / or impact generating elements including the drive part 5 , the transmission part 6 and the work pressing part 7 . the dust absorbing portion 10 b has a plurality of apertures or openings 10 b 1 formed thereat with a predetermined interval provided therebetween for the purpose of absorbing thereat the dusts as well as the heat which will be generated from the drive part 5 , the transmission part 6 and the work pressing part 7 and the control part 8 as shown in fig4 ( a ) and ( b ). the apertures 10 b 1 may be circular or oval . the dust absorbing pipe 10 has one end , that is , the end of the dust guiding pipe 10 a , brought to an opening 11 provided at one side wall of the column 2 of the casing a where the dust absorbing pipe 10 is conductive with the outer air of the casing a . a pressure adjusting valve 12 is provided on the casing a . the pressure adjusting valve 12 may be operated to adjust the atmospheric pressure which may be varied in the casing a due to the vertical motion of the ram 7 . the pressure adjusting valve 12 may be a valve to be manually operated or to be electromagnetically operated with a pressure sensor . as shown in fig2 the electric press of the invention has an outer pipe 15 extending therefrom to the outside of the clean spaced room for guiding the absorbed dusts out into the atmosphere outside of the clean spaced room where the electric press is located . the outer pipe 15 has one end connected to the end of the dust absorbing pipe 10 at the opening 11 of the casing a and has the opposite end connected to a blower 16 located outside of the clean spaced room . the blower 16 located outside of the clean spaced room . the blower 16 is operated to suck the dust generated within the casing a into the dust absorbing pipe 10 , and blow the dust through the outer pipe 15 outside of the clean spaced room . a flow meter 17 may be provided to the outer pipe 15 . fig6 and 7 show a second embodiment of the invention , wherein the electric press has no dust absorbing pipe 10 , which is provided in the first embodiment of the invention . according to the second embodiment , the outer pipe 15 has one end connected to the opening 11 of the casing a and has the opposite end connected to the blower 16 located outside of the clean spaced room in the same manner as in the first embodiment . in the second embodiment , the dusts generated in the casing a are absorbed at the opening 11 of the casing a and the absorbed dusts are blown out of the clean spaced room through the outer pipe 15 out into the outer atmosphere by the blower 16 . fig8 shows a third embodiment of the invention , wherein the electric press has cooling slits 13 provided to the head 1 of the casing a such that the electric press may be functionally effective when it is used at a place other than the clean spaced room as well . when the electric press is used at a place other than the clean spaced room , the cooling slits 13 are opened to allow the outer air to flow into the casing a , thereby to cool down the essential elements generating heat in the casing a including the drive part 5 , the work pressing part 7 and the control part 8 . the cooling slits 13 may be optionally closed to render the casing a airtight . more particularly the cooling slits 13 are composed of a fixed group of slits collectively denoted by the reference numeral 13 a and comprising a plurality of slits 13 a 1 and a group of slits 13 b 1 provided to a plate 13 b as shown in fig9 ( a ). as shown in fig8 and 9 ( a ), the fixed group of slits 13 a may be provided optionally to the top and side walls of the casing a in a manner that the respective slits 13 a 1 are arranged in parallel with each other with a predetermined interval provided therebetween . the plate 13 b has a plurality of slits 13 b 1 provided thereto in a manner that the respective slits 13 b 1 are arranged in parallel with each other with a predetermined interval provided therebetween . the plate is movably attached to the casing a in reference to the fixed group of slits 13 a . for the purpose of movably attaching the plate 13 b to the casing a , an optional proper number of threaded holes 13 c 1 are provided to the casing a with reference to the fixed group of slits 13 a . on the other hand , the same number of elongated openings 13 c 2 are provided to the plate 13 b with reference to the slits 13 b 1 . the plate 13 b may be fixedly attached to the casing a by means of screws 13 d which are inserted into the elongated openings 13 c 2 of the plate 13 b respectively and threaded into the respective threaded holes 13 c 1 of the casing a . when the screws 13 d are loosened , the plate 13 b may be moved in the longitudinal directions of the elongated openings 13 c 2 to the place where the slits 13 b 1 are vertically in alignment with the slits 13 a 1 as shown in fig9 ( b ) and to the place where the slits 13 b 1 are displaced from the slits 13 a 1 to close the cooling slits 13 , thereby to render the casing a airtight as shown in fig9 ( c ). as shown in fig1 , the plate 13 b may be replaced by a plate 13 e having no slits provided thereto as shown in fig1 . the plate 13 e is fixedly attached to the casing a by means of the screws 13 d to close the slits 13 a 1 to render the casing a airtight . with the screw 23 d being unscrewed , the plate 13 e may be removed from the casing a to allow the outer air to flow into the casing a through the slits 13 a 1 . although the invention has been described in conjunction with the specific embodiments thereof , it is to be understood that many variations and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims .