The present invention relates to a camshaft device, which allows a plurality of components to be assembled to a main shaft, and a method for manufacturing the camshaft device. The camshaft device may include: a main shaft lengthily extending in the lengthwise direction; at least one cam lobe assembled to the main shaft and formed eccentrically from a rotation axis of the main shaft; at least one journal bearing assembled to the main shaft and formed to rotatably support the main shaft; and at least one guide shaft assembled to the main shaft and installed between the cam lobe and another cam lobe so as to align an assembling position of the cam lobe or the journal bearing.

A method for jointing elements, each having a cutout, on a shaft by a device for producing a control shaft, comprises disposing the elements vertically above one another, aligned, and fixed. The method also comprises pushing the shaft in vertically from above though the cutouts of the elements by a traversable guide carriage of the device and displacing by a pneumatic piston of the device the traversable guide carriage and the shaft attached thereto until a maximum first press-in force is reached. The method further comprises displacing by at least two spindles of an electric spindle drive of the device the traversable guide carriage and the shaft when the maximum first press-in force is exceeded.

A method for jointing elements, each having a cutout, on a shaft by a device for producing a control shaft, comprises disposing the elements vertically above one another, aligned, and fixed. The method also comprises pushing the shaft in vertically from above though the cutouts of the elements by a traversable guide carriage of the device and displacing by a pneumatic piston of the device the traversable guide carriage and the shaft attached thereto until a maximum first press-in force is reached. The method further comprises displacing by at least two spindles of an electric spindle drive of the device the traversable guide carriage and the shaft when the maximum first press-in force is exceeded.

A heating/heat-retaining device, particularly to a heating/heat-retaining device used in the forging process, and more particularly to an opening-and-closing type heater and a wind generator shaft forging process using the same. The opening-and-closing type heater comprises a base, a tube body mounted on the base and a tube body opening-and-closing mechanism; the tube body comprises a fixed tube body and a movable tube body, the fixed tube body and the movable tube body are arc-shaped shells, and form a hollow shape when the openings thereof match with each other; the tube body opening-and-closing mechanism is connected to the movable tube body for realizing the opening-and-closing of the movable tube body and the fixed tube body. The invention solves heat retaining and heating problems during the forging process of the main shaft forgings and avoids internal defects due to rapid temperature drop of the main shaft forgings.

A heating/heat-retaining device, particularly to a heating/heat-retaining device used in the forging process, and more particularly to an opening-and-closing type heater and a wind generator shaft forging process using the same. The opening-and-closing type heater comprises a base, a tube body mounted on the base and a tube body opening-and-closing mechanism; the tube body comprises a fixed tube body and a movable tube body, the fixed tube body and the movable tube body are arc-shaped shells, and form a hollow shape when the openings thereof match with each other; the tube body opening-and-closing mechanism is connected to the movable tube body for realizing the opening-and-closing of the movable tube body and the fixed tube body. The invention solves heat retaining and heating problems during the forging process of the main shaft forgings and avoids internal defects due to rapid temperature drop of the main shaft forgings.

A method for obtaining a camshaft for an internal-combustion engine having a structure made of a single piece includes obtaining the camshaft by starting from a metal tubular element. The cams are obtained by expanding the tubular element within a die using high-pressure fluid. The tubular element can have an enlarged thickness in portions that are to form the cams. Forming with high-pressure fluid can be obtained using gas or liquid (for example, water or oil) at high pressure, at room temperature or at a higher temperature. The piece obtained is subjected to thermal treatment and to a grinding operation.

A method for obtaining a camshaft for an internal-combustion engine having a structure made of a single piece includes obtaining the camshaft by starting from a metal tubular element. The cams are obtained by expanding the tubular element within a die using high-pressure fluid. The tubular element can have an enlarged thickness in portions that are to form the cams. Forming with high-pressure fluid can be obtained using gas or liquid (for example, water or oil) at high pressure, at room temperature or at a higher temperature. The piece obtained is subjected to thermal treatment and to a grinding operation.

An electric power steering device includes an input shaft, an output shaft, a torsion bar provided at an inner diameter side of the input shaft and the output shaft with coaxially coupling the input shaft and the output shaft each other; and, a torque detection sleeve which is arranged at an outer diameter side of the torque detection encoder part, and of which a rear end portion is externally fitted and fixed to the fitting part. A nitride layer is formed at least at a part, at which the torque detection encoder part is formed, of the outer peripheral surface of the output shaft.

The prevent invention proposes to provide a method for manufacturing a constant velocity drive shaft, which can manufacture especially a constant velocity drive shaft among other drive shafts with efficiency and stable high accuracy. The method for manufacturing a constant velocity drive shaft using a closed cold forging device having a plurality of mold pairs structured with an upper mold and a lower mold, comprises a first process for processing a forming material for forming the constant velocity drive shaft to form a first forming material having first large diameter portions by applying a pressure from a first upper mold of a first mold pair and pressures from both sides of the forming material, a second process for forming a second forming material having second large diameter portions by applying a pressure from a second upper mold of a second mold pair and pressures from both sides of the first forming material with respect to the first forming material being mold-processed in the first process, and a third process for forming third large diameter portions by applying a pressure from a third upper mold of a third mold pair and pressures from both sides of the second forming material with respect to the second forming material being mold-processed in the second process.

The prevent invention proposes to provide a method for manufacturing a constant velocity drive shaft, which can manufacture especially a constant velocity drive shaft among other drive shafts with efficiency and stable high accuracy. The method for manufacturing a constant velocity drive shaft using a closed cold forging device having a plurality of mold pairs structured with an upper mold and a lower mold, comprises a first process for processing a forming material for forming the constant velocity drive shaft to form a first forming material having first large diameter portions by applying a pressure from a first upper mold of a first mold pair and pressures from both sides of the forming material, a second process for forming a second forming material having second large diameter portions by applying a pressure from a second upper mold of a second mold pair and pressures from both sides of the first forming material with respect to the first forming material being mold-processed in the first process, and a third process for forming third large diameter portions by applying a pressure from a third upper mold of a third mold pair and pressures from both sides of the second forming material with respect to the second forming material being mold-processed in the second process.