摘要:
A biaxially oriented polyester film which is well balanced between sliding properties and transparency and having an enhanced uniformity in thickness is prepared by a process wherein a polyester, predominantly comprised of polyethylene terephthalate, is extruded into a sheet form extrudate; the extrudate is quenched to a temperature of below Tg to obtain a solidified, substantially amorphous film; the film is drawn in the longitudinal direction at a drawing ratio of larger than 2.4 but smaller than 6.5; the film is quenched; and then, the film is drawn in the transverse direction at a drawing ratio of at least 2.5. The drawing in the longitudinal direction is carried out in two steps wherein:(i) in the first drawing step, the substantially amorphous film is drawn in one or more stages at a total drawing zone length (l.sub.1) of at least 50 mm so that the resulting polyester film possesses a birefringence of 1.times.10.sup.-3 to 12.times.10.sup.-3 ;(ii) the drawn film is kept, without being quenched to a temperature of not higher than the Tg, in contact with a roll maintained at 100.degree. to 130.degree. C.; and then,(iii) in the second drawing step, the film is drawn at a drawing ratio of larger than 1.6 but smaller than 2.7 in one stage at a drawing zone length of shorter than l.sub.1 /2.
摘要:
Breakage of the actuator moving the movable platen in the clamping device of an injection moulder is prevented. The clamping device includes a movable platen shifting device increasing and decreasing a horizontal distance between the movable platen (3) and the fixed platen (2). It includes an actuator (41), a clevis pin connecting the actuator (41) and the movable platen (3), a clevis pin holding part holding a central axis of the clevis pin perpendicular to a moving direction of the movable platen (3), and a clevis pin connecting part that connects the actuator (41) and the clevis in. The clevis pin connecting part is a supporting structure rotating with the clevis pin. The clevis pin connecting part is supported by the movable platen (3). The clevis pin, the clevis pin connecting part, and the front end of the actuator are aligned in a straight line.
摘要:
An injection foam molding machine according to the present invention includes: a clamping unit that moves a movable die plate 3 relative to a fixed die plate 2 to clamp the die plates; a fixed side mold attached to the fixed die plate 2; a movable side mold attached to the movable die plate 3; a plurality of drive units 50 that widen an interval between both of the die plates 2 and 3; and a die-plate-interval adjusting unit 60 that adjusts a distance over which the movable die plate 3 is moved by the drive units 50, and when a molten foam resin is foamed, an inner-side interval within the mold cavity is determined, and thus an accurate molded product can be obtained.
摘要:
A mechanism for advancing and retreating a movable die plate toward and from a fixed die plate includes a moving base in which the upper surface thereof is connected integrally with the movable die plate and a slide unit is installed on the lower surface thereof. A pair of track rails are provided on the base and form a linear guide by engaging with the slide unit. A ball screw shaft is supported in parallel with the track rails by a bearing provided on the base and has an axial direction restrained rotatably. A servomotor drives the ball screw shaft and a ball screw nut is installed on the lower surface of the moving base to threadedly engage with the ball screw shaft, and the ball screw shaft and the ball screw nut are provided at an arbitrary position between the paired track rails for linear guidance.
摘要:
In a die clamping apparatus for an injection molding machine or the like, die clamping means for coupling and pressing a moving die plate 9 to a fixed die plate via a tie bar 15 has a die clamping cylinder consisting of two stages of a large-diameter cylinder 11 and a small-diameter cylinder 31 and a ram formed into two stages of a large-diameter ram 13 and a small-diameter ram 25. The large-diameter ram 13 is inserted in the large-diameter cylinder 11, and the small-diameter ram 25 is inserted in the small-diameter cylinder 31. The proximal end portion of the tie bar 15 is connected directly to the small-diameter ram 25. Large oil chambers 11c and 11d are provided on both sides of the large-diameter ram 13, and a small oil chamber 11e is provided on the tie bar connection side of the small-diameter ram 25. An oil pressure is supplied appropriately to each of the large oil chambers and the small oil chamber in the die clamping cylinder to appropriately move the tie bar 15. The apparatus constructed as described above can be manufactured at a low cost, and useless time for eliminating a gap between a ring grooves in the tie bar and an engagement teeth of half nuts caused by the adjustment to die thickness can be reduced.
摘要:
A generally disc-shaped flywheel which is an integral one-piece forged structure formed by forging of a carbon steel blank and consisting of an inner portion having a friction surface and an outer ring gear portion disposed radially outwardly of the inner portion. The flywheel is formed by forging the carbon steel blank to obtain an intermediate product consisting of the inner portion and the outer ring gear portion, hardening the friction surface of the inner portion of the intermediate product, and shot peening the hardened friction surface to form a multiplicity of recesses in the hardened friction surface.
摘要:
The present invention relates to a process for preparing a highly tensilized polyester film that has enhanced mechanical properties in both longitudinal and transverse directions. The process involves the simultaneous machine and transverse direction stretching and subsequent heat setting of a film that has already been highly stretched in the machine and transverse directions individually. During the simultaneous stretching process both the temperature and rate of linear movement of the film are controlled.
摘要:
Breakage of the actuator moving the movable platen in the clamping device of an injection molder is prevented. The clamping device includes a movable platen shifting device increasing and decreasing a horizontal distance between the movable platen (3) and the fixed platen (2). It includes an actuator (41), a clevis pin connecting the actuator (41) and the movable platen (3), a clevis pin holding part holding a central axis of the clevis pin perpendicular to a moving direction of the movable platen (3), and a clevis pin connecting part that connects the actuator (41) and the clevis pin. The clevis pin connecting part is a supporting structure rotating with the clevis pin. The clevis pin connecting part is supported by the movable platen (3). The clevis pin, the clevis pin connecting part, and the front end of the actuator are aligned in a straight line.
摘要:
The present invention relates to a process for preparing a polyester film which has not only uniaxially enhanced mechanical properties but also biaxially enhanced mechanical properties. The process involves heat-setting a biaxially oriented polyester film at a temperature above that used for the machine and transverse direction stretching and above that used for the machine direction re-stretching, but at least 10.degree. C. below the melting point of the polyester, then re-stretching the film in both the machine and transverse directions, and re-heat-setting the film.
摘要:
A polymeric-shaped article for use as film such as microfilm, overhead projector film, reprographic film, layout base, etc., and for insulating capacitors, which has excellent transparent, slippery and dielectric properties, and the process for realizing the same, the polymeric-shaped article having a polar surface such as polyester, polyamide, polyolefins, polyimide, polyvinyl alcohol, polyethylene terephthalate or polyethylene-2,6-naphthalate, to which is bonded a multiplicity of nodules of TiO.sub.2, each nodule having a diameter in the range of from about 0.01 to about 10 .mu.m, a height or thickness in the range of from about 0.01 to about 0.5 .mu.m, and an area ratio of TiO.sub.2 to total surface of from about 0.01 to about 50%; and the process being that of exposing at least one side of the surface of the article to water vapor and bringing a tetrafunctional titanium compound such as TiCl.sub.4, tetraethyltitanate, tetraisopropyltitanate, tetra-n-butyltitanate or mixture thereof, into contact with the surface, the processing temperature being at least greater than 30.degree. C.