Abstract: A rotation controller controls a rotation mechanism for rotation of a spindle. A movement controller causes, while the spindle is rotating, a feed mechanism to bring a cutting tool into contact with a workpiece to cause the cutting tool to cut the workpiece. The rotation controller controls a spindle rotation speed so as to accelerate or decelerate the rotation of the spindle, and the movement controller brings the cutting tool into contact with the workpiece after the rotation controller starts the rotation of the spindle, and separates the cutting tool from the workpiece while the spindle rotation speed is put under the acceleration control or deceleration control exercised by the rotation controller.

Abstract: A throttle valve device includes a shaft in a cylindrical passage, a slit passing through the shaft from one lateral side to another lateral side of the shaft, a pair of bearings on both sides of the cylindrical passage and rotatably supporting one end part and another end part of the shaft, and a circular-plate valve inserted into the slit of the shaft and rotatable to open and close the cylindrical passage. A length of the slit on the one lateral side of the shaft is, in an axial direction of the shaft, longer than a length of the slit on the other lateral side of the shaft. A round end hole is formed at an end of the slit in the one end part of the shaft on the one lateral side of the shaft.

Abstract: A throttle valve device includes a body, a valve, a motor, and a cover. The body defines a passage, a motor space, and a connecting portion that connects the motor space to the passage. The motor includes a motor yoke made of a magnetic material, a plurality of magnets that are arranged on an inner circumferential surface of the motor yoke. The plurality of magnets are magnetized in a state where the motor yoke is disposed in the motor space of the body. The plurality of magnets are arranged in a circumferential direction in the motor yoke with a space. The connecting portion is aligned with the space between the plurality of magnets in a radial direction of the motor yoke.

Abstract: A throttle valve device includes a coil spring arranged in a body between a valve gear and a valve and having a spring end extending radially outward. A first guide covers an end of the coil spring and includes a first guide hook that contacts the spring end. A body hook in the body is capable of contacting a tip end part of the first guide hook. A valve gear hook in the valve gear is capable of contacting a base end part of the first guide hook. The first guide hook has a protrusion protruding toward the spring end between the tip end part and the base end part. The first guide hook is deformable by receiving the spring force at the protrusion as an effort while a fulcrum is at a contact between the first guide hook and the body hook or the valve gear hook.

Abstract: A throttle valve device includes a shaft in a cylindrical passage, a slit passing through the shaft from one lateral side to another lateral side of the shaft, a pair of bearings on both sides of the cylindrical passage and rotatably supporting one end part and another end part of the shaft, and a circular-plate valve inserted into the slit of the shaft and rotatable to open and close the cylindrical passage. A length of the slit on the one lateral side of the shaft is, in an axial direction of the shaft, longer than a length of the slit on the other lateral side of the shaft. A round end hole is formed at an end of the slit in the one end part of the shaft on the one lateral side of the shaft.

Abstract: A valve gear includes a gear portion configured to rotate by drive torque transmitted from an actuator, a boss portion provided on the gear portion and having a cylindrical outer wall, and one or more extension portions extending in an axial direction from the gear portion on a radial outer side of the boss portion. A coiled spring including a first hook provided at end portion on a gear portion side, and a second hook provided at end portion on an opposite side to the gear portion so that the first hook and the second hook are respectively locked to each other on opposite sides in a circumferential direction of the extension portion. A valve gear subassembly formed by assembling the valve gear and the spring is housed in a valve gear accommodating chamber of the body, and the second hook of the spring is locked to the body.

Abstract: A throttle valve device includes a body, a shaft, a pair of bearings, a valve, a motor, a valve gear, a coil spring, a first guide, and a second guide. At least one of the first guide and the second guide includes a circular holder that faces an end surface of the coil spring, a spring-end holding portion that outwardly protrudes from the circular holder and is configured to hold a spring end of the coil spring, a hub that is rotatably connected to the shaft, and a connecting portion that connects the hub and the circular holder. The first guide is in contact with a lever only at an end surface of the hub. The second guide is in contact with one of the pair of bearings, which is located close to the valve gear, at an end surface of the hub.

Abstract: A throttle valve device includes a body, a valve, a valve gear, a motor, an intermediate gear, an intermediate shaft and a cover. A guiding hole is formed in the cover and the intermediate shaft engages the guiding hole. A positioning reference pin is formed in one of the cover and the body at a position around the motor. A positioning reference hole is formed in the other of the cover and the body at a position around the motor. The body and the cover are positioned with respect to each other by both engaging between the intermediate shaft and the guiding hole and engaging between the positioning reference pin and the positioning reference hole. The body and the cover are fixed to each other by a fixing member.

Abstract: A throttle valve device includes a body, a valve, a motor, a speed reducer, and a cover. The body that defines a passage and a motor space therein. The motor includes a motor yoke, a magnet, a motor shaft, a pair of motor bearings, an armature core, a commutator, a brush, and a brush holder. The motor yoke is made of a magnetic material. The brush holder holds the brush. The motor yoke has an open end that is covered by the brush holder.