Toshiba Kikai Kabushiki Kaisha

Other

Yazaki Corporation

Kazuo Nagashima

Takeshi Momochi

Masahito Shiozaki

Hideo Fujie

Jun Fujita

Takao Date

Minoru Hamamura

Tadashi Tanaka

Sadaji Hayama

Akira Ochiai

Toshihiro Ueta

Haruhiko Kikuchi

Masaaki Mitsuzono

Harukatsu Goto

Chikara Watanabe

Mashahito Shiozaki

Yasuo Sakai

Hideki Hayashi

In a multi-axis machine tool (M) including an angular dividing head (HD) having a spindle head ( ) mounted thereto, the positional correction includes determining an error representative vector componentwise representative of a plurality of positional errors with respect to a plurality of axes of the spindle head at a respective angular position dividable by the angular dividing head, and correcting an arbitrary positional error of the spindle head by calculating a component vector of the error representative vector associated with the respective angular position.

Spindle head positional error correction method for multi-axis machine tool

A spindle head holder ( ) is pivoted on a base member ( ), a linear drive ( ) is mounted to the base member ( ), a linear guide ( ) is mounted to the spindle head holder ( ), and an engagement member ( ) is engaged with both linear drive and linear guide at a substantially identical part ( ) thereof.

Machine tool with pivotal spindle head

A history of function values of a spindle rotation frequency in each time period from present to past is stored in a data table D and corrective coefficients are stored in advance in a corrective coefficient table C relating the coefficients to the location in the data table D. Each location and corrective coefficient are read out from the corrective coefficient table C and the function value of the spindle rotation frequency corresponding to the location is read out from the data table D. The compensation value is calculated from the total sum of each product of the function value and the corrective coefficient in each location and compensate the NC command position with the compensation value.

Machine tool displacement correcting apparatus

A main-shaft malfunction-state detector in an air bearing type machine tool, in which an abnormal contact of a main shaft with a housing is reliably and automatically detected. The contacting state of the main shaft,and the housing,is detected through the presence of electric conductivity by a contact detection device,A contact decision device,determines the contact of the main shaft,with the housing,based on the detected conductivity, thus automatic and certain preventative measures, such as the main shaft of the machine tool stops and so on, are based on the above decision.

Main-shaft malfunction-state detector in an air bearing type machine tool

A main-shaft malfunction-state detector in an air bearing type machine tool, in which an abnormal contact of a main shaft with a housing is reliably and automatically detected. The contacting state of the main shaft 11 and the housing 13 is detected through the presence of electric conductivity by a contact detection means 31. A contact decision means 32 determines the contact of the main shaft 11 with the housing 13 based on the detected conductivity, thus automatic and certain preventative measures, such as the main shaft of the machine tool stops and so on, are based on the above decision.

A combination of setting a correction value of an atmospheric temperature for each temporal section in response to a predicted value of a variation of the atmospheric temperature in a day and a delayed variation of a temperature of hydraulic oil due to thermal inertia and correcting a command value for a temperature regulation of the hydraulic oil at a supply source of the hydraulic oil in response to the correction value of the atmospheric temperature, performing a feed forward compensation of the temperature of the hydraulic oil with respect to the variation of the atmospheric temperature for the day as a cyclic period, permits a working body of hydraulic oil to be kept at an adequate temperature, even under working conditions subjected to significant influences of atmospheric temperature variations and thermal inertia.

Method and system for temperature control of hydraulic oil

Letting a differential value of a command value of a position command to a position control loop be an input variable, a feed forward compensation value is calculated depending on the input variable and a combination of a proper vibration frequency and an attenuation constant of a vibration in a moving direction of a moving mechanism to be set in a parameter setting manner, and a feed forward compensation is effected for the command value of the position command to the position control loop by the feed forward compensation value.

Servo control method and servo control system for feed drive system

A machine with a worn detection function for a tool capable of reliably carrying out a worn detection for a tool. A present consumption power PW1 of a built-in motor 19, driving a main shaft 11, is watched and compared with a reference consumption power PW2, previously defined, by using a load meter 31, an A/D converter 32, a comparator 33 and a processing unit 34, thereby wear on the tool 12 is detected when the consumption power PW1 is larger than the reference consumption power PW2 as a cutting process is advanced. The main shaft 11 is supported by air static-pressure bearings 14 to 18, so that noise created with rotating, which exert an influence upon the consumption-power detected value, is extremely smaller as compared with the conventional antifriction bearing and so on. Thereby allowing delicate fluctuation of the consumption power to be detected, and naturally the worn detection for the tool 12 to be ensured.

Machine tool with worn-detection function for tool

The present invention provides an air bearing type machine tool capable of carrying out a process with a high load for cutting iron or the like and controlling the degree air is used. The air bearing type machine tool includes a main shaft, an air bearing supporting the main shaft, and an air pressure regulating device capable of regulating the pressure of air supplied to the air bearing. The air pressure regulating device, in turn, has an air feed portion supplying air to the air bearing, a processing load detection device for detecting the degree of processing load, a processing power detection device for detecting the degree of processing power, and an air pressure defining device for controlling the pressure of air fed from the air feed portion by using the detected values of the processing load and the processing power. The pressure of air supplied to the air bearing can be changed, so that the rigidity of the air baring can be changed in response to the processing load or the like, that is the process with from the low load to the high load can be carried out, with the result that the used air can be controlled at the minimal required amount.

Air breaking type machine tool

A method of correcting an error in mounting a workpiece includes a step of determining a position and a direction of a tool on a coordinate system of the workpiece on the basis of command numerical values, a step of correcting an error in a preset quantity in every direction, a step of obtaining quinaxial coordinate values satisfying the position and the direction of the tool as a result of performing the error correction and a step of giving a numerical control command to a driving unit of each axis on the basis of the quinaxial coordinate values. An apparatus for correcting an error in mounting a workpiece includes an attitude detecting unit, a correcting unit, a coordinate calculating unit and a command unit that correspond to those steps, respectively. The machining can be thereby effected by correcting mounting errors that are not confined to the three X-, Y- and Z-directional position parallel movements in simultaneous quinaxial control machining without requiring a machining program.

Method of correcting error in mounting workpiece and apparatus therefor

An adaptive control system for a roll grinding machine. A desired radius as a function of longitudinal direction of the roll is preprogrammed. A power driven grinding wheel is applied to the roll and power to the grinding wheel is monitored. For each longitudinal position of the grinding wheel, the actual radius of the roll is measured and the desired radius noted. From these numbers, a desired power for driving the grinding wheel is computed. The actual power is compared with the desired power and the pressure of the grinding wheel against the roll is adjusted accordingly.

Control system for roll grinding machine

In a cambering device of a roll grinding lathe of the type wherein a grinding wheel is moved toward and away from the center of a roll by means of a cambering cam while the grinding wheel is moved in the longitudinal direction of the roll, there are provided electrical or mechanical means to detect the longitudinal position of the grinding wheel and electrical or mechanical means controlled by the position detecting means for varying the rotational speed or the cambering cam so as to vary the cambering profile.

Cambering devices of roll grinding lathes

In an apparatus for profile grinding a closed curved surface such as a trochoidal curved surface of the type wherein the attitude of a worktable which supports a workpiece is profile controlled in accordance with a master profile corresponding to the closed curved surface to be formed in the workpiece, the axis of a grinding wheel is maintained at a fixed position, a mechanical information is generated by the cooperation of a master cam having a peripheral profile corresponding to the profile of the closed curved surface and a master cam normally urged against the peripheral profile, and the attitude of the worktable is controlled in accordance with the mechanical information. Where a grinding wheel having a diameter different from a predetermined value is used, a primary feed calculated by an equation to be described later is applied to the grinding wheel thus enabling to use a grinding wheel of any diameter.

Growing community of inventors

Shizuoka-ken, Japan

Kazuo Nagashima