Abstract: In a silicone rubber composition comprising (A) an organopolysiloxane of the organic peroxide curing type or addition reaction curing type, (B) a curing agent, and (C) non-spherical silica fine powder, (D) a mixture of 50-95% by weight of spherical fused silica having a mean particle size of 7-40 .mu.m and 50-5% by weight of spherical fused silica having a mean particle size of 0.1-6.5 .mu.m is blended in an amount of 100-900 parts by weight per 100 parts by weight of components (A) and (B) combined. The composition has a low viscosity and high fluidity despite high loading and heat cures into a product having low coefficients of shrinkage and expansion and low water absorption.

Abstract: A silicone rubber composition comprising (A) an organopolysiloxane having at least two aliphatic unsaturated hydrocarbon groups attached to a silicon atom, (B) finely divided silica, (C) aluminum hydroxide surface treated with silazanes, (D) an organohydrogenpolysiloxane having at least two hydrogen atoms attached to a silicon atom, and (E) a platinum catalyst is suitable for use as a high-voltage electrical insulator. The silicone rubber has durable high-voltage electrical insulating properties and is firmly bondable to core materials.

Abstract: In a semiconductive silicone elastomer composition comprising an organopolysiloxane containing at least two aliphatic unsaturated hydrocarbon groups attached to a silicon atom, an organohydrogenpolysiloxane containing at least two hydrogen atoms attached to a silicon atom, and a conductive agent, the conductive agent consists of 1-10 wt % of conductive carbon and 99-90 wt % of a conductive filler having a volume resistivity of 10.sup.1 -10.sup.8 .OMEGA.-cm other than the conductive carbon. The conductive agent is blended in an amount of 20-60 wt % of the entire composition. The composition having the conductive agent uniformly dispersed therein yields a semiconductive silicone elastomer having a volume resistivity of 10.sup.5 -10.sup.10 .OMEGA.-cm with a dispersity of 1 to 10.

Abstract: A silicone rubber composition of the addition curing type containing an organopolysiloxane having at least two aliphatic unsaturated hydrocarbon groups in a molecule, silica, an organohydrogenpolysiloxane, a platinum catalyst, and a liquid organopolysiloxane blocked with a (CH.sub.3).sub.3 SiO.sub.1/2 unit at either end, having a monovalent hydrocarbon group (exclusive of an aliphatic unsaturated hydrocarbon group) attached to a silicon atom, provides a composition heat curable to a silicone rubber having improved weathering and tracking resistance and thus useful for high-voltage electrical insulators. Also, a silicone rubber composition containing an organopolysiloxane, an inorganic filler and an organic peroxide is improved by using as the organopolysiloxane one or more organopolysiloxanes of the formula: R.sup.6.sub.f SiO.sub.(4-f)/2, and blending therein aluminum hydroxide.

Abstract: By curing or semi-curing an addition curable silicone resin composition comprising a phenyl-containing organopolysiloxane, placing an addition or peroxide curable silicone rubber composition in close contact with the cured or semi-cured resin, and heat curing the silicone rubber composition, there is prepared a composite material in which silicone resin and silicone rubber are firmly joined together.

Abstract: A cured product of an epoxy resin composition is integrally and firmly joined to a cured product of an organic peroxide--or addition reaction-curable silicone rubber composition to form an integral composite. The integral composite having practically acceptable adhesion force can be simply and briefly produced without using a primer.

Abstract: A liquid silicone rubber composition contains (A) an organopolysiloxane having at least two alkenyl groups, (B) a reinforcing silica filler, (C) a condensation catalyst, (D) a silanol group-containing siloxane wetter, (E) an organohydrogenpolysiloxane having at least two hydrogen atoms, and (F) a platinum catalyst. Components (C) and (D) assist in blending a large amount of the silica filler in the composition. The composition is smoothly flowing, quickly curable and suitable for injection molding.

Abstract: A novel curable organopolysiloxane-epoxy resin composition, which is capable of giving a cured body having excellent mechanical properties without the problem of adhesion to the metal mold, is proposed. The composition comprises: (a) an epoxy resin; (b) an organopolysiloxane containing vinyl groups; (c) an organohydrogenpolysiloxane as the crosslinking agent of the component (b); (d) a platinum compound as a catalyst for the hydrosilation reaction; and (e) a specific organic aluminum compound, such as tris(acetylacetonato) aluminum, each in a specified proportion.

Abstract: To a heat-curable silicone rubber composition comprising (a) an organopolysiloxane having at least two alkenyl groups in a molecule, (b) an organohydrogenpolysiloxane having at least two hydrogen atoms in a molecule, and (c) a platinum catalyst is added (d) ammonia or an ammonia precursor so that ammonia or ammonia precursor is present in an amount of 10 to 500 parts by weight of nitrogen per million parts by weight of the total of components (a), (b) and (c) in a cured product of the heat-curable silicone rubber composition. The composition cures into a silicone rubber having minimized compression set without a need for secondary vulcanization.

Abstract: In a heat-curable silicone elastomer composition comprising (A) an organopolysiloxane having at least two aliphatic-unsaturated hydrocarbon groups each bonded to a silicon atom and (B) an organohydrogenpolysiloxane having at least two hydrogen atoms each bonded to a silicon atom, there is blended (C) a hydrosilylating catalyst in the form of a hydrosilylation-promoting compound on a porous filler having a mean particle size of 0.1-100 .mu.m and a pore volume of 0.5-5 cm.sup.3 /g. The composition is stable during storage at room temperature, but quickly curable at elevated temperatures through hydrosilylation reaction.

Abstract: A heat curable silicone elastomer composition includes (1) an organopolysiloxane having at least two aliphatic unsaturated hydrocarbon groups, (2) an organohydrogenpolysiloxane having at least two hydrogen atoms, and (3) a platinum-containing silicone resin having a melting or softening point of 49.degree. to 150.degree. C. and containing 0.05-0.3 mol % of SiOH group. The composition is storage stable at room temperature and efficiently cures through hydrosilylation reaction at high temperature.

Abstract: A high pressure pump for an engine fuel injection system, wherein the pump has a plurality of positive displacement pumping devices that are operating so that their delivery cycles overlap and so that the instantaneous speed of the pumping devices during their delivery strokes is constant so as to minimize pressure variations in the system and avoid the necessity of having the pump being driven in synchronized relationship to the engine output shaft. This permits the use of a variable speed drive so that the pump can be driven at speed ratios depending upon engine demand and/or eliminates the necessity for positive drives to maintain synchronization. A number of embodiments showing different pump configurations are disclosed.

Abstract: A process for preparing a liquid silicone rubber base composition of the type which comprises (A) an organopolysiloxane of the following average compositional formula (1)R.sub.a SiO.sub.(4-a)/2 (1)wherein each R independently represents an unsubstituted or substituted monovalent hydrocarbon group and a is a value of from 1.95 to 2.05, and (B) a finely divided silica filler is described. The process comprises the steps of mixing a first portion of the ingredient (A) and the ingredient (B) at a temperature not higher than 80.degree. C., further mixing a second portion of the ingredient (A) with the mixture obtained in the first step at a temperature not higher than 80.degree. C. and subjecting the resultant mixture to thermal treatment at a temperature of 130.degree. to 200.degree. C. By this, the base composition has good fluidity and is able to yield a cured product having good tear strength under stress.

Abstract: A heat-curable silicone elastomer composition comprising (A) a thermoplastic resin containing a platinum catalyst and a hydrosilylation reaction retarding agent, (B) an organopolysiloxane having at least two unsaturated aliphatic hydrocarbon groups bonded to silicon atoms in its molecule, and (C) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in its molecule. The composition is excellent in storage stability. That is, even when stored for a long time, the composition has good stability at room temperature and retains curability at high temperatures.

Abstract: By curing either one of an organic peroxide-curable silicone rubber composition and an organic peroxide-curable unsaturated polyester resin composition and then curing the other composition while placing it in close contact with the cured composition, there is obtained a composite material in which an organic peroxide-cured silicone rubber is closely and firmly joined with an organic peroxide-cured unsaturated polyester resin.

Abstract: A primer composition has blended therein an organic silicon compound having in a molecule at least one group of the formula: ##STR1## wherein R.sup.1 is a monovalent hydrocarbon group or a group represented by QSi( R.sup.4 O).sub.a (R.sup.5).sub.3-a, Q is a divalent organic group, R.sup.4 and R.sup.5 each are a monovalent hydrocarbon group, a is an integer of 0 to 3, R.sup.2 and R.sup.3 each are a hydrogen atom or a monovalent hydrocarbon group, and n is 0, 1 or 2. The primer composition is a useful adhesive since it is effective for joining silicone elastomers and similar adherends to supports such as paint coated metals and resins.

Abstract: Silicone rubber compositions based on an organopolysiloxane are improved in release properties by blending a silane having both a fluorinated hydrocarbon group and an alkanoyloxy group and/or an organopolysiloxane having an alkanoyloxy or alkanoyloxyalkyl group.

Abstract: A four cylinder, two cycle crankcase compression, diesel fuel injected engine having an improved injection pump including an integral timer for timing the initiation and duration of fuel injection. A control system and method is disclosed for maintaining uniform running speed during all running conditions while reducing the amount of smoke produced by the engine. The speed uniformity is obtained by selecting a cylinder that deviates from the desired speed and adjusting the fuel injection of the cylinder firing preceding that cylinder on the next cycle. The engine also includes an improved arrangement for determining the timing of an event by measuring the incremental rotational speed of the engine immediately prior to the event to be timed.

Abstract: An accumulator type of fuel injection nozzle having an injection valve that is controlled by an electromagnet within the accumulator chamber includes a feeder wire structure formed axially in the outer housing assembly of the injection nozzle for energizing the electromagnet. This feeder wire structure includes one or more axially extending wire passages formed in the outer housing assembly, preferably in a structure through which is formed a fuel inlet conduit, constructed so as to withstand the high pressure within the accumulator chamber, to provide a sufficient seal without increasing the outer diameter of the injection nozzle, and to provide easy installation of the injection nozzle without interference from the engine. One or more feeder wires are contained within the wire passages for energizing the electromagnet.

Abstract: An accumulator type of fuel injection nozzle having an injection valve, a first electromagnet for initiating fuel injection, and a second electromagnet for controlling the lift amount of the injection valve is provided with an energizing arrangement which enables effective fuel injection control but which greatly reduces the risk of burning damage to the electromagnets. The amp-turn characteristics of the first electromagnet coil provide for a rapid start-up time wherein the peak magnetic flux is reached relatively quickly. In contrast, the amp-turn characteristics of the second electromagnet coil provide for a more gradual start-up time so that peak magnetic flux is reached more gradually. The second electromagnet coil is also adapted to achieve a relatively large magnetic flux without the need for large current supply. In operation, when the second electromagnet is energized, such energization is started before energization of the first electromagnet for a particular fuel injection cycle.