Abstract: A machining control device controls spindle rotational speed. A set of stability limit curve data is stored indicating a relation between a spindle rotational speed and a limit cutting-in amount whereby chatter vibrations are inhibited. Spindle rotational speed and tool cutting-in amount in starting machining are set based on the data. Vibrations of the spindle are detected during cutting. Whether chatter vibrations have occurred is determined based on vibrations detection. Spindle rotational speed is controlled with reference to the data to inhibit chatter vibrations. Cutting-in amount in starting machining is set to be less than a maximum cutting-in amount within a stable region of the data, and spindle rotational speed in starting machining is set to be less than a rotational speed when the cutting-in amount is maximum within the stable region. Spindle rotational speed is increased by an amount of a predetermined rotational speed when chatter vibrations have occurred.

Abstract: A gear machining condition setting device receives a feeding amount determining parameter and a cutting speed determining parameter. A storage unit stores a cutting-in amount calculation formula representing a relation between a cutting-in amount and a characteristic value determined based on a feeding amount and the feeding amount determining parameter. The feeding amount of the hob, corresponding to the cutting-in amount, is computed using the cutting-in amount calculation formula. Further, the storage unit stores data of a constant temperature curve representing a relation between the cutting-in amount and the cutting speed where a cutting edge of the hob is set at a predetermined temperature. Using the data, the cutting speed is computed based on the cutting-in amount and the cutting speed determining parameter with reference to the constant temperature curve.

Abstract: A gear machining condition setting device receives a feeding amount determining parameter and a cutting speed determining parameter. A storage unit stores a cutting-in amount calculation formula representing a relation between a cutting-in amount and a characteristic value determined based on a feeding amount and the feeding amount determining parameter. The feeding amount of the hob, corresponding to the cutting-in amount, is computed using the cutting-in amount calculation formula. Further, the storage unit stores data of a constant temperature curve representing a relation between the cutting-in amount and the cutting speed where a cutting edge of the hob is set at a predetermined temperature. Using the data, the cutting speed is computed based on the cutting-in amount and the cutting speed determining parameter with reference to the constant temperature curve.

Abstract: A work equipment boom is adapted to be attached at one end to a main body of a construction machine and attached at the other end to a work equipment arm. the work equipment boom includes a boom main component. The boom main component is integrally formed by expanding a tubular material. The boom main component has a proximal end portion and a distal end portion. The proximal end portion includes a first end part arranged to be disposed adjacent to the main body and has a shape which increases in horizontal width as it gets nearer to the first end part. The distal end portion includes a second end part arranged to be disposed adjacent to the work equipment arm and has a shape which increases in horizontal width as it gets nearer to the second end part.

Abstract: A work equipment boom is adapted to be attached at one end to a main body of a construction machine and attached at the other end to a work equipment arm, the work equipment boom includes a boom main component. The boom main component is integrally formed by expanding a tubular material. The boom main component has a proximal end portion and a distal end portion. The proximal end portion includes a first end part arranged to be disposed adjacent to the main body and has a shape which increases in horizontal width as it gets nearer to the first end part. The distal end portion includes a second end part arranged to be disposed adjacent to the work equipment arm and has a shape which increases in horizontal width as it gets nearer to the second end part.