摘要:
The invention relates to compositions for producing polymethacrylimide foams having reduced pore size. The inventive method allows production of a microporous foam with an especially homogeneous pore size distribution without having to use insoluble nucleation agents.
摘要:
A block-copolymer containing at least two different blocks wherein block A contains (meth)acrylate monomers the copolymer having a glass transition temperature of less than 15° C., block B contains (meth)acrylate monomers the copolymer having a glass transition temperature of more than 25° C. being free of thio-containing substances in the polymer chain, characterized in that one block contains at least one photoinitiator chemically bound to the chain.
摘要:
The invention relates to a molded body consisting of plastic with a material thickness of at least 150 $g(m)m at any point. Said body contains a polymer mixture of an impact-resistance modified poly(meth)acrylate plastic, a polymethyl methacrylate matrix, elastomer particles contained in said matrix and a fluoropolymer. According to the invention, the fraction of the fluoropolymer in the mixture is between 30 and 95 wt. % and the polymer mixture of the impact-resistance modified poly(meth)acrylate plastic and the fluoropolymer is present in an outer layer with a continuous material thickness of at least 10 $g(m)m. The invention is characterized in that the impact-resistance modified poly(meth)acrylate plastic consists of between 20 and 70 wt. % poly(meth)acrylate matrix and between 30 and 80 wt. % elastomer particles.
摘要:
A drill has a housing formed with an outlet hole, a fan expelling an air stream from the outlet hole, a drive spindle projecting from the housing adjacent the outlet and centered on and rotatable about an axis, and a chuck body carried on the housing. A tightening sleeve rotatable about the axis on the chuck body carries a plurality of radially shiftable jaws, and interengaging screw formations operatively engaged between the body and the sleeve can shift the jaws radially in the guides on rotation of the sleeve relative to the body. A shield sleeve angularly fixed to the housing and surrounding the tightening sleeve has a rear end juxtaposed with the housing radially outside the outlet hole such that the air stream enters the shield sleeve. Inside the shield sleeve forward of its rear end a passage and a particle-expelling hole collect drilling particles and blow them out the particle-expelling hole.
摘要:
The adhesive bonding of matted PMMA with customary polymerization adhesives leads to very shiny bond seams, since the cured polymerization adhesives have a shiny surface. This emphasizes the very joining zones which it is intended that the viewer of bonded products should not perceive. The adhesive should therefore be matted after curing. The adhesive has for its basis a polymerization adhesive, preferably a (meth)acrylate-based adhesive. Two different kinds of silica are added as disperse powder to the polymerization adhesive, namely a silica powder having an average particle size of from 1 μm to 10 μm (matting agent) and a silica powder having an average particle size of more than 10 μm up to 200 μm (texturing agent).
摘要:
A drill chuck has a chuck body, a holder body, and a front sleeve surrounding the bodies, with jaws between them. A ring of teeth on one of the bodies can be engaged by a pawl angularly fixed on the other of the bodies. When engaged, the pawl and the array of teeth allow rotate relative to the chuck body in a tightening direction but not in a loosening direction. Respective interengaging stops on the other body and on the front sleeve limit relative angular movement of the front sleeve on the other body between a pair of angularly offset end positions. A back control sleeve has a cam formation engageable with the pawl in only one of the end positions to hold the pawl in the freeing position. The pawl is biased by a spring in the other end position into the locking position.
摘要:
A drill chuck has a chuck body formed with an annular row of radially outwardly directed teeth. A sleeve axially fixed but rotatable about the chuck axis on the chuck body has a plurality of angularly spaced guides holding respective radially displaceable jaws. A screwthread displaces the jaws radially toward each other on rotation of the sleeve in a tightening direction on the body and displaces the jaws radially apart on rotation of the sleeve in an opposite loosening direction. A pawl pivoted on the inner sleeve has a tip radially displaceable between an inner blocking position engaging the body teeth and allowing rotation of the sleeve on the body only in the tightening direction and an outer freeing position clear of the body teeth and permitting rotation of the sleeve on the body in both of the directions. A spring urges the pawl into the inner blocking position.
摘要:
A tool or workpiece has a mounting collar open axially outward, formed with a radially inwardly directed angled flank, and having a radial outer surface of noncircular cross-sectional shape. A chuck has a body formed with an axially forwardly open socket shaped to receive the collar with the axes generally coaxial and having an inner surface of a noncircular cross-sectional shape substantially complementary to the shape of the collar outer surface. A plurality of jaws axially fixed in the socket have radially movable ends engageable inside the collar and each formed with a radially inwardly and axially outwardly directed face. A cam having a face centered on the axis is engageable with the jaw front ends such that axial rearward shifting of the cam presses the jaw front ends outward and thereby presses the jaw faces against the collar flank to lock the collar in the socket.
摘要:
A drill chuck has an externally toothed body, a plurality of jaws, and a tightening ring rotatable on the body in tightening and loosening directions. Screwthreads between the tightening ring and the jaws move the jaws radially. A pawl engageable with the teeth is angularly fixed on the tightening ring and can shift between a retaining position engaging the teeth and a freeing position disengaged from the teeth. An adjustment sleeve is limitedly angularly displaceable on the body relative to the tightening ring between a locked end position and an unlocked end position. A cam on the adjustment sleeve can displace the pawl into the retaining position when the adjustment sleeve is in the locked end position and into the freeing position when the adjustment sleeve is in the unlocked end position. A locking part can engage the pawl in the retaining position thereof to lock the chuck.
摘要:
A drill chuck has a chuck body centered on and rotatable about an axis and a plurality of jaws spaced angularly about the axis, radially shiftable on the body between inner and outer positions, and each having a grip edge extending along a line substantially parallel to the axis and a pair of flanks meeting at the grip edge and extending generally radially outward therefrom. The flanks of each jaw diverge radially inward from the flanks of adjacent jaws so that a tool shank engaged between the flanks of two adjacent jaws will be pushed radially toward the axis on movement of the jaws inward from the outer positions.