Nsk Corporation

Nippon Seiko Kabushiki Kaisha

Asuka Trading Co., Ltd.

Shinya Nakamura

Soichiro Kato

Masaru Akiyama

Shiroji Yabe

Yoshiaki Katsuno

Yoshifumi Inagaki

Masaki Matsuoka

Koji Nishii

Kiyoharu Maruta

Norio Sagara

The linear guide apparatus includes a guide railincluding a rolling body rolling grooveand a friction apply unitassembled to the guide rail. The friction apply unitincludes a unit main body, a brake member, an oil pressure cylinderand a plate spring. The brake memberis disposed so as to face the side surfaceof the guide railand can be contacted with the other portions of the side surfacethan the rolling body rolling groovethereof. The oil pressure cylinderincludes a piston memberwhich is structured to be driven in a positive direction to thereby press the brake memberagainst the side surfaceof the guide railand also the piston membercan be driven in the opposite direction to thereby remove the pressure of the brake memberfrom the side surface

Linear guide apparatus

The linear guide apparatus includes a guide rail including a rolling body rolling groove and a friction apply unit assembled to the guide rail . The friction apply unit includes a unit main body , a brake member , an oil pressure cylinder and a plate spring . The brake member is disposed so as to face the side surface of the guide rail and can be contacted with the other portions of the side surface than the rolling body rolling groove thereof. The oil pressure cylinder includes a piston member which is structured to be driven in a positive direction to thereby press the brake member against the side surface of the guide rail and also the piston member can be driven in the opposite direction to thereby remove the pressure of the brake member from the side surface

A spindle apparatus capable of exhibiting a good interchangeability of a tool holder without any necessity for managing a gap between an end surface of the tool holder and an end surface of a spindle shaft and, besides, obtaining a high tool holding rigidity. Small- and large-diameter portions are formed in the outer surface of the spindle shaft having a taper hole formed in the shaft end. A sleeve formed with a fluid passageway communicating with the outside is fitted, with interferences, to the outer surface thereof. On the other hand, a flange having a diameter larger than a taper shank is provided at a proximal portion of the taper shank of the tool holder. A fluid pressure is applied to the fluid passageway of the sleeve, thereby making the sleeve contact with the flange of the tool holder that is fitted to the spindle shaft. Thereafter, the sleeve is fixed to the spindle shaft by removing the fluid pressure, and the tool holder is supported with a high rigidity.

Spindle apparatus

A control device for a spindle apparatus including a spindle in a housing supported by bearings includes a sensor that senses the axial elongation of the spindle during rotation and outputs monitoring signals representing whether such an elongation exists. The monitored signals are compared and a variation value per unit time is calculated. A switching circuit receives the variation value and stops rotation of the spindle when the variation value is equal to or greater than a preset reference value by detecting abrupt elongation in the axial direction of the spindle immediately before seizure may happen and rapidly stopping rotation of the spindle to prevent seizure of the spindle.

Control apparatus and method for preventing seizure in a spindle

This specification discloses a bearing mounting device in which while the hydraulic pressure in a hydraulic mechanism for applying a preload to a bearing is being adjusted in a state in which the fixing sleeve of a fixing mechanism for fixing the bearing to a shaft has been expanded by hydraulic pressure, a predetermined preload is applied to the bearing through a spacer provided between the fixing mechanism and the hydraulic mechanism and through the fixing mechansim. The hydraulic pressure in the fixing mechanism is released with the predetermined preload being applied and the fixing sleeve is fixed to the shaft, whereby the bearing is fixed in its appropriately preloaded state.

Growing community of inventors

Maebashi, Japan

Shinya Nakamura