Abstract:
PURPOSE: A variable compression ratio control method is provided to prevent the NVH(Noise, Vibration, and Harshness) deterioration of a device according to the variation of a compression ratio by implementing a variable compression ratio on the basis of a gear transmission stage number for lowering fuel injection amount and engine RPM in the transmission of a gear. CONSTITUTION: A variable compression ratio control method comprises the following steps: checking a current gear transmission stage while driving an engine(S10); confirming whether the gear transmission stage varies in the checking process(S20); determining the condition of a gear transmission stage number for changing is a high gear transmission stage number according to a high speed high load drive area(S30); and changing the compression ratio of a combustion chamber into a different compression ratio from the high gear transmission stage number according to the high speed high load drive area when satisfying the condition of the gear transmission stage number(S40). [Reference numerals] (AA) Low gear: High compression ratio; (BB) High gear: Low compression ratio; (S10) Operate an engine; (S20) Gear shifted?; (S30) Gear stage > A; (S40) Drive a compression ratio changer
Abstract:
PURPOSE: A high-carbon steel wheel bearing and a heat-treating method thereof are provided to improve a material and a process, thereby optimizing the contact-service life of the high-carbon steel wheel bearing component under the condition of an identical load. CONSTITUTION: A high-carbon steel wheel bearing comprises 1.00 to 1.10 wt% of C, 0.50 to 0.70 wt% of Si, 1.00 to 1.20 wt% of Mn, 1.45 to 1.65 wt% of Cr, 0.20 to 0.40 wt% of Ni, 0.02 to 0.04 wt% of Nb, less than 0.025 wt% of P, and less than 0.008 wt% of S. The high-carbon steel wheel bearing includes an inner race, an outer race, and plural balls. The inner race is assembled to be inserted into the outer circumference of a wheel hub. The outer race is assembled to be inserted into the inner circumference surface of a knuckle. The plural balls are interposed between the inner race and the outer race for relatively rotating. The heat-treating method of the high-carbon steel wheel bearing comprises: A step of quenching a bearing-shaped steel component for 60 minutes at the temperature of 840 degrees Celsius; a step of hardening the quenched component for 30 minutes at the temperature of 780 degrees Celsius; and a step of tempering the hardened component at 60 minutes at the temperature of 175 degrees Celsius. [Reference numerals] (AA) Quenching OIL temperature: 115°C
Abstract:
PURPOSE: A steering device of a vehicle is provided to protect a driver effectively in the expansion of an airbag. CONSTITUTION: A steering device of a vehicle comprises a steering column(20), a steering shaft(30), a bracket(50), a lever(60). The upper end of the steering column is coupled with a steering wheel(10) and the lower end of the steering column is arranged into the front direction of a vehicle. The upper end of the steering shaft is coupled with the lower end of the steering column to be rotated and the lower end of the steering shaft is coupled with a gear box(40) to be rotated. The bracket is located in the front of the steering column and the steering shaft and comprises a bent portion(50b) bent by determined force. The bracket is divided into a top portion(50a) and a bottom portion(50c) based on the bent portion. The upper part of the bracket is connected to a steering column through a first connection bar(51). A lever is located between the steering shaft and a bracket and installed to be rotated in a vehicle body. The lever is divided into a upper lever(60a) and a lower lever(60c) based on a rotary shaft(60b).
Abstract:
An apparatus for a limited slip differential is provided to improve durability and driving feeling by reducing impact and noise while a gear of a spider and driven clutch are connected with each other. In an apparatus for a limited slip differential, a differential limitation apparatus is comprised of a differential case, a spider(110), driven clutches(121,122), and a side gear. The spider is installed inside the differential case, and the spider distributes delivered power to an axle. The driven clutches are installed on the both side of the spider while being connected with the spider respectively. The side gear is combined with the driven clutch and the axle by the spline, and it is supported by the differential case. Elastic members(131,132) which elastically support the protrusion are formed in a connecting part of the differential case assembled with the protrusion of spider.
Abstract:
A winner material removal system within the exhaust gas of the gasoline direct injection engine and their control method are provided to eject the exhaust gas burned incompletely to outside. A winner material removal system within the exhaust gas of the gasoline direct injection engine comprises an exhaust pipe(11) ejecting the exhaust gas generated from the gasoline direct injection engine(10), a NOx removing catalyst(12) for collecting the nitric oxide among the exhaust gas, a tail pipe(13) ejecting the exhaust gas to airborne, a metal filter member(21) which is formed in the exhaust pipe and removes the winner material among the exhaust gas, a catalyst pipe(22) connected between the metal filter member and nitrogen oxide removal catalyst, and a filter rear end oxygen sensor(35) formed between the metal filter member and nitrogen oxide removal catalyst.
Abstract:
Boron steel for crank shaft is provided to improve toughness while securing the same strength as non-heat-treated steel by adding boron. Boron steel for crank shaft contains Fe as base material, C 0.20~0.25 weight%, Si 0.15~0.35 weight%, Mn 1.00~1.50 weight%, P 0.03 weight% or less, S 0.04~0.07 weight%, Cr 0.25~0.35 weight%, Ti 0.02~0.05 weight%, N 0.01~0.02 weight%, Al 0.01~0.03 weight%, and B 10~40ppm. Si serves to improve rigidity and elasticity. Mn is employed in the matrix to improve the strength and toughness of material. Cr serves to increase the strength in quenching and tempering. Al serves to improve strength and toughness of material by enhancing curability and miniaturizing grain. B serves to improve hardenability.