Abstract: A pneumatic tire maintaining excellent traction performance for the entire life of the tire. The tire (10) has blocks (18) each demarcated by both a circumferential groove formed in the tread and lateral grooves crossing the circumferential groove, and also has recessed parts (20). Each recessed part (20) is formed in at least one of those both wall surfaces of each block (18) that are oriented to the lateral direction of the tire, and the circumferential width (C) of each recessed part (20) is increased from the tread side of the block (18) toward the radially inside of the tire. Because the edge effect of the blocks (18) at the portions between the lateral grooves and the recessed parts (20) can be maintained in an excellent state even if the wear of the tire (10) progresses, the edge effect of the entire blocks can be maintained in an excellent state, and excellent traction performance can be maintained for the entire life of the tire.

Abstract: In a pneumatic tire for a heavy load, it is an object of the present invention to enhance a biased abrasion resistance of a tread while maintaining durability. A component Fin toward an axial inner direction of the tire which is an opposite direction from an axial outer direction of the tire is applied to a force acting on a kicking end 16B of a land portion 16. With this, abrasion of the kicking end of the land portion can be moderated, and a biased abrasion resistance can be enhanced. A groove wall 20 of a lug groove 14 is provided with a step portion 22, a tread side groove width WA in a tread side of the step portion is widened toward an axial outer side of the tire, and a width WS of the step portion 22 is increased toward the axial outer side of the tire, thereby suppressing the lift from the road surface 26 at the tread-in end 16A of the land portion 16.

Abstract: A motor-driven welding gun has a servomotor for displacing a movable electrode tip toward and away from a fixed electrode tip. The servomotor has a motor housing with a copper pipe which is inserted therein when the motor housing is cast. The copper pipe provides a coolant passage in the motor housing for supplying a coolant therethrough. When the coolant passage is supplied with the coolant, the motor housing is forcibly cooled, reducing the amount of heat generated by the servomotor.

Abstract: A pneumatic tire including a carcass, a belt arranged at the outside of the carcass in a radial direction and having at least two belt layers, at least one belt reinforcing layer arranged so as to overlap with the belt and extend over a widthwise outer end thereof, and a tread rubber arranged at the outside of the belt in the radial direction. A pair of split auxiliary belt layers are arranged so as to overlap at least with both widthwise outer end portions of a widest-width belt reinforcing layer. Reinforcing elements having an inclination angle different from that of reinforcing elements in the belt reinforcing layer are embedded in the split auxiliary belt layer for decreasing the wearing rate at the tread end portion of the tire to effectively control irregular wear.

Abstract: A motor-driven welding gun has a servomotor (34) for displacing a movable electrode tip (30) toward and away from a fixed electrode (32). The servomotor (34) has a motor housing (38) with a copper pipe (72) which is inserted therein when the motor housing (38) is cast. The copper pipe (72) provides a coolant passage (70) in the motor housing (38) for supplying a coolant therethrough. When the coolant passage (70) is supplied with the coolant, the motor housing (38) is forcibly cooled, reducing the amount of heat generated by the servomotor (34).

Abstract: In a pneumatic tire comprising a carcass, a belt arranged at the outside of the carcass in a radial direction and comprised of at least two belt layers, at least one belt reinforcing layer arranged so as to overlap with the belt and extend over a widthwise outer end thereof, and a tread rubber arranged at the outside of the belt in the radial direction, a pair of split auxiliary belt layers are arranged so as to overlap at least with both widthwise outer end portions of a widest-width belt reinforcing layer and reinforcing elements having an inclination angle different from that of reinforcing elements in the belt reinforcing layer are embedded in the split auxiliary belt layer for decreasing the wearing rate at the tread end portion of the tire to effectively control irregular wear.

Abstract: By the present invention, there are provided a catalyst for polyester preparation, which comprises a solid titanium compound containing titanium, oxygen, carbon and hydrogen and having a Ti—O bond and which has a maximum solubility in ethylene glycol, as measured when the catalyst is dissolved in ethylene glycol under heating at 150° C., of not less than 3,000 ppm in terms of a titanium atom, a catalyst for polyester preparation, which comprises a titanium-containing solution wherein a contact product of a hydrolyzate of a titanium halide or a hydrolyzate of a titanium alkoxide with a polyhydric alcohol is dissolved in ethylene glycol in an amount of 3,000 to 100,000 ppm in terms of a titanium atom, a process for preparing a polyester using the catalyst, and a polyester prepared by the process.

Abstract: A pneumatic tire comprises a pair of bead portions, a pair of sidewall portion, a tread portion, a radial carcass of at least one ply, and a belt, wherein the tread portion is provided with two or more circumferential main grooves formed in a tread rubber at an inner region sandwiched by both shoulder regions and one or more circumferential ribs defined by two adjoining circumferential main grooves, and at least two circumferential fine grooves are formed in the circumferential rib.

Abstract: By the present invention, there are provided a catalyst for polyester preparation, which comprises a solid titanium compound containing titanium, oxygen, carbon and hydrogen and having a Ti—O bond and which has a maximum solubility in ethylene glycol, as measured when the catalyst is dissolved in ethylene glycol under heating at 150° C., of not less than 3,000 ppm in terms of a titanium atom, a catalyst for polyester preparation, which comprises a titanium-containing solution wherein a contact product of a hydrolyzate of a titanium halide or a hydrolyzate of a titanium alkoxide with a polyhydric alcohol is dissolved in ethylene glycol in an amount of 3,000 to 100,000 ppm in terms of a titanium atom, a process for preparing a polyester using the catalyst, and a polyester prepared by the process.

Abstract: A hit-less cell switching device capable of switching ATM (Asynchronous Transfer Mode) cells between a system ZERO and a system ONE is disclosed. The system ZERO includes a first cell switch, a first input cell gate, a first output cell gate, and a first shaper. Likewise, the system ONE includes a second cell switch, a second input cell gate, a second output cell gate, and a second shaper. First, a controller opens the first and second input cell gates and first output cell gate, closes the second output cell gate, and puts the first and second cell switches and first and second shapers in a fully switched condition, thereby initializing the switching device. Subsequently, the controller closes the second input cell gate, evacuates queue buffers included in the second cell switch and second shaper, and opens the second output gate. After putting the two cell switches and two shapers in an in-switching state, the controller closes the first input cell gate and opens the second input cell gate simultaneously.

Abstract: The present invention provides a catalyst for polyester production capable of producing a polyester with high catalytic activity and a process for producing a polyester using the catalyst. The catalyst for polyester production comprises a solid titanium compound which is obtained by dehydro-drying a hydrolyzate obtained by hydrolysis of a titanium halide and which has a molar ratio (OH/Ti) of a hydroxyl group (OH) to titanium (Ti) exceeding 0.09 and less than 4. The present invention also provides a method to obtain a polyester having a small increase of the acetaldehyde content during the molding. This method comprises bringing a polyester, which is obtained by the use of a titanium compound catalyst and in which the reaction has been completed, into contact with a phosphoric ester aqueous solution or the like having a concentration of not less than 10 ppm in terms of phosphorus atom.

Abstract: The present invention provides a method for estimating a tire wear life which enables estimation of the tire wear life accurately in a short time. In this method, a rubber index Gi of a rubber test piece which is made of the same material as the material used in the tire tread portion of the tire whose tire wear life is to be estimated is measured using an abrasion tester which can be operated under a slip ratio of about 0.5 to 5% (step 100). Then, friction energies of the tire in free rolling, in a state in which the tire is provided with a toe angle, in a state in which a side force is applied to the tire, in a state in which a driving force is applied to the tire and in a state in which a braking force is applied to the tire are measured (step 102), respectively. An expected value of the tire wear life T1 is calculated from the rubber index Gi and the friction energies obtained above (step 104). The tire wear life is estimated from the expected value of the tire wear life T1 thus obtained (step 106).

Abstract: A wear resistance index G1 of a tire whose wear life is to be estimated is measured by the Lambourn abrasion tester. Then, friction energies in free rolling, when the tire is fitted with a toe angle, under application of a side force, under application of a braking force and under application of a driving force of the tire are measured. An expected value of the wear life T1 is calculated using the wear resistance index G1 and the friction energies thus obtained and the wear life of the tire is estimated on the basis of the expected value of the wear life T1. The wear life of a tire can be estimated accurately in a short time in accordance with the method for estimating a tire wear life of the present invention.

Abstract: A pneumatic radial tire (20) comprises a radial carcass (22) of at least one ply, and a reinforcing belt (23) arranged on the outer peripheral side of the radial carcass (22). The reinforcing belt (23) is in the form of a helical belt layer (24) wherein a ribbon (40), which is comprised of a rubber (41) and a plurality of reinforcing cords (42) embedded in the rubber (41), is successively wound in a helical manner at an angle with respect to the circumferential direction of a tread portion. The ribbon (40) forming the helical belt layer (24) has a cross-section in which the reinforcing cords (42) are dispersed in the thickness and width directions of the ribbon (40).

Abstract: A copolymer of ethylene and an alpha-olefin having an ethylene content of from 30 to 90 mole %, a number average molecular weight of from 300 to 30,000 and a molecular weight distribution defined by a Q value (the ratio of the weight average molecular weight to the number average molecular weight of not more than 3 and a Z value (the ratio of the maximum value of the molecular weight to the minimum value of the molecular weight when the molecular weight is measured by gel permeation chromatography) of from 15 to 200. The said copolymer can be produced by a process comprising copolymerizing ethylene with an alpha-olefin in the liquid phase in the presence of a polymerization catalyst composed of a combination of a soluble vanadium compound and an organoaluminum compound in the co-presence of hydrogen, characterized in that(a) the copolymerization is carried out in a continuous manner,(b) the concentration of the vanadium compound in the polymerization system is maintained at 0.

Abstract: A copolymer of ethylene and an alpha-olefin having an ethylene content of from 30 to 90 mole %, a number average molecular weight of from 300 to 30,000 and a molecular weight distribution defined by a Q value (the ratio of the weight average molecular weight to the number average molecular weight) of not more than 3 and a Z value (the ratio of the maximum value of the molecular weight to the minimum value of the molecular weight when the molecular weight is measured by gel permeation chromatography) of from 15 to 200. The said copolymer can be produced by a process comprising copolymerizing ethylene with an alpha-olefin in the liquid phase in the presence of a polymerization catalyst composed of a combination of a soluble vanadium compound and an organoaluminum compound in the co-presence of hydrogen, characterized in that(a) the copolymerization is carried out in a continuous manner,(b) the concentration of the vanadium compound in the polymerization system is maintained at 0.

Abstract: A copolymer of ethylene and an alpha-olefin having an ethylene content of from 30 to 90 mole %, a number average molecular weight of from 300 to 30,000 and a molecular weight distribution defined by a Q value (the ratio of the weight average molecular weight to the number average molecular weight) of not more than 3 and a Z value (the ratio of the maximum value of the molecular weight to the minimum value of the molecular weight when the molecular weight is measured by gel permeation chromatography) of from 15 to 200. The said copolymer can be produced by a process comprising copolymerizing ethylene with an alpha-olefin in the liquid phase in the presence of a polymerization catalyst composed of a combination of a soluble vanadium compound and an organoaluminum compound in the co-presence of hydrogen, characterized in that(a) the copolymerization is carried out in a continuous manner,(b) the concentration of the vanadium compound in the polymerization system is maintained at 0.

Abstract: A method and apparatus for grinding a metal need of an air jet loom for reducing the air resistance in a weft guide path of profiled reed blades.

Abstract: The present invention provides a catalyst for polyester production capable of producing a polyester with high catalytic activity, a process for producing a polyester using the catalyst and a polyester produced thereby. The catalyst comprises a solid titanium compound obtained by dehydro-drying a hydrolyzate obtained by hydrolysis of a titanium halide and which has a molar ratio (OH/Ti) of a hydroxyl group (OH) to titanium (Ti) exceeding 0.09 and less than 4. In the process, the polyester is obtained by polycondensing an aromatic dicarboxylic acid, or an ester-forming derivative thereof, and an aliphatic diol, or ester-forming derivative thereof, in the presence of the catalyst. The resulting polyester has excellent transparency and tint, a titanium content of 1 to 100 ppm, a magnesium content of 1 to 200 ppm and a magnesium to titanium weight ratio of not less than 0.01.