Abstract: A numerical controller which, after once stopping a slave axis during superposing control, can easily resume the superposing control. In the superposing control, a motion amount for a master axis and a motion amount for the slave axis are added to a workpiece coordinate value of the master axis and a workpiece coordinate value of the slave axis, respectively, to update their present position data (I2, II2). These motion amounts are supplied also to servo processing (I3, II3) for the master axis and the slave axis, where an amount obtained by superposing a motion amount &dgr;zIm for the master axis ZIm on a motion amount &dgr;zIIs for the slave axis ZIIs is supplied to the servo processing for the slave axis ZIIs. When a slave axis motion stop command is issued, the motion of the slave axis is stopped and a motion amount &dgr;zIm for the master axis ZIm is subtracted from the workpiece coordinate value of the slave axis ZIIs.

Abstract: A numerical controller for performing an machining operation by controlling relative position of a workpiece and a tool in synchronism with a rotational position of a rotational axis to which the workpiece or the tool is attached, without causing time delay of position control of the tool relative to the workpiece in varying a rotational velocity of the rotational axis. A rotational position &thgr;i(i=0, 1, . . . ) of a workpiece on the rotational axis, a position (Xi, Zi) of the tool relative to the workpiece when the workpiece is at the rotational position &thgr;i, and the rotational velocity Vi of the workpiece from the rotational position &thgr;i to the rotational position &thgr;i+1 are set in advance. Time Ti required for rotating the workpiece from the rotational position &thgr;i to the rotational position &thgr;i+1 at the rotational velocity Vi is obtained.

Abstract: A machining program checking method is provided for a numerical control device which controls an NC lathe for performing a machining operation with a plurality of tools simultaneously mounted on a turret thereof, wherein interference of the tools with a workpiece or with various parts of the lathe can be surely detected before the machining operation is actually executed.

Abstract: An interactive type numerical control apparatus having an interactive type data input function for controlling the operation of a machine tool by creating a machining program based on input data. A composite tool (3) able to carry out a plurality of different machining operations is selected and an NC sentence is created based on data input designating the tool path of the composite tool (3). With this arrangement, a plurality of different numerically controlled NC machining operations can be effectively executed by the composite tool (3).

Abstract: In a first heterojunction bipolar transistor (HBT) of the present invention, base layers and collector layers are respectively divided into a plurality of layers and one of the base layers provided closer to the collector layer reiogn is set lower in impurity concentration than the other thereof provided closer to an emitter layer, thus solving a problem that thermal histories during epitaxial growth or during processes cause a set impurity distribution to be destroyed due to diffusion and thus a heterojunction is shifted from a p-n junction. Since minority carriers in the base can smoothly flow toward the collector, there can be realized an excellent HBT having a very high current gain and a very high cut-off frequency.