Abstract: In an axial flow fan, a line extending from a center axis and passing a corner where a following edge and a radially outer edge of a blade of an impeller meet is arranged forwardly in a rotational direction from an another corner where a leading edge of the blade and a radially outer surface of a hub meet. Furthermore, a camber ratio of the blade, which is minimum at a joint with the hub across the blade, monotonically increases to be maximum at the radially outer edge of the blade.

Abstract: A spring device includes of a coil spring case formed of right, left, back and front side plates and a spring receiving plate, a coil spring having a linear spring property, and a spring urging member for urging the coil spring into the coil spring case. A distance between the right and left side plates of the spring case is set a little larger than an outer diameter of the coil spring. A distance between the back and front side pates of the spring case is set about 1.5 to 2 times larger than the outer diameter of the coil spring, and a length of the spring case is set smaller than a free length of the coil spring. The coil spring is deformed and a non-linear spring property is obtained when the coil spring is urged through the spring urging member.

Abstract: A stator core having twelve stator poles, coils wound around the stator poles, and a hybrid type rotor are included. The stator poles inwardly and radially extended from an annular yoke portion. Each of the respective stator poles has the same number of inductors. The coils are connected so that a pair of the stator poles being substantially symmetric with respect to a point are excited in opposite polarities. The rotor is arranged with a predetermined air gap with respect to the inductors, the rotor has a pair of rotor cores each of which has rotor teeth facing to the inductors and a permanent magnet magnetized in the axial direction sandwiched therebetween. The angles between inductors at the corresponding positions of adjacent stator poles are defined by repeating three sets of angular distributions each of which includes three times of 29.1 degrees and one time of 32.7 degrees when a number of rotor teeth equals 100.

Abstract: A multi-polar rotary machine comprises a and a cylindrical outer rotor arranged concentrically with the stator and with an air gap therebetween. The stator has two splitted stator elements and a ring shaped permanent magnet held between the stator elements and magnetized so as to form N and S poles in the axial direction of the stator. Small axially separated stator teeth A and ? and B and B are formed on the outer peripheral surface of the splitted stator elements. Stator windings for A phase and B phase are wound around the respective stator elements. The small stator teeth A, ?, B and B are circumferentially shifted from corresponding small rotor teeth by a ¼ pitch of the small stator teeth, respectively. Each of the stator and rotor is formed of pressed powder consisting of soft magnetic material, and of resin and/or inorganic material.

Abstract: A centrifugal fan includes a scroll casing consisting of first and second flat base walls, a circumferential side wall. An air inlet is formed on the first base wall, an exhaust port is formed on the side wall. A backflow prevention mechanism is arranged in the airflow path to prevent backflow from the exhaust port during fan halting. The mechanism has a flap that is rotatably supported by the first base wall and its rotation axis is inclined with respect to the vertical direction so that the flap shuts the airflow path under its own weight in a horizontal-use position where the rotating shaft of the motor is horizontal. The flap is inserted into a slit from the outside and is held by a stopper plate. A protrusion, which contacts with the rim of the flap when the flap shuts the airflow path, is formed inside the walls.

Abstract: An impeller of a centrifugal fan, the impeller used in the centrifugal fan having a casing and the impeller rotatably mounted in the casing. The impeller includes a hub connecting a number of blades equiangularly disposed in a circumferential direction. The hub includes an outer circular hub partially covering an outer peripheral edge of the blade, and an inner circular hub partially covering an inner peripheral edge of the blade. The hubs are concentrically formed, and an opening is provided between the inner and outer circular hubs. The inner circular hub, outer circular hub and opening are arranged to allow air to flow back across the inner circular hub and within the casing to cool a control circuit disposed within the casing.

Abstract: A brushless DC motor drive system includes a pole-position detector for detecting respective pole positions of permanent magnets of a rotor of a brushless DC motor. A present speed computing unit computes a present speed of the brushless DC motor on the basis of an output signal from the pole-position detector. A speed differential computing unit computes a speed differential between a speed command and the present speed. An energization start time computing unit computes an energization start time in a present instance on the basis of an energization start time in a preceding instance, and the speed differential. An energization start instruction unit instructs energization start upon the elapse of the energization start time in the present instance from a phase changeover point in time. An energization completion time computing unit computes an energization completion time by subtracting the energization start time in the present instance from preceding pulse time.

Abstract: In a centrifugal fan including a casing, a rotatable impeller disposed in the casing, a motor for driving the impeller, a control board for controlling the motor, and an ejection port for cooling air, a dust proof projection is formed to the casing to prevent invasion of dusts from the ejection port to the motor and the control board. With this simple arrangement, invasion of dusts to a coil portion and a control board of the motor can be reduced while suppressing a manufacturing cost. In this case, when the dust proof projection is disposed to a gap between the inner peripheral surface of a side wall of the casing and the outer peripheral surface of the impeller along the outer peripheral surface of the impeller in an arc-shape, a dust proof effect can be more improved.

Abstract: Multiple fans of cascade connection comprises at least two fans of cascade connection, and a commutation device arranged between the two fans. The commutation device is composed of a cylindrical case and a plurality of planar plates, each extending radially from the center axis of the cylindrical case to an inner peripheral wall of the cylindrical case, and extending axially in the cylindrical case. The two fans are connected coaxially and identical substantially in design with each other.

Abstract: There is no surveillance camera system optimum for monitoring an important monitor place by a surveillance camera mainly for crime prevention day and night without humans in attendance, which can automatically monitor the place without humans in attendance and, when something suspicious is found, follow the suspicious without humans in attendance, and accurately monitor the suspicious at high precision. The present invention provides a surveillance camera driving method achieving such a system having the function of obtaining video image signals by two or more surveillance cameras each having a three-dimensional positioning pan tilt head function, organically processing the video information, comparing the processed information with input data of a plane picture or the like or data of pictures of a front view and a side view or the like, and determining whether the processed video signal is the same as the input data or not.

Abstract: A control system for a liquid infusion apparatus comprises a plurality of liquid infusion devices, each having a common connector of liquid infusion device side for an electric power supply line and a communication line, a plurality of racks stacked one another, each for receiving each of the liquid infusion devices, a plurality of common connectors of rack side, each mounted on each of the racks a base unit, and a connector provided on the base unit so as to connect an electric power supply line and a communication line to the connectors of lack side. Each of the common connectors of rack side is connected to each of the common connectors of liquid infusion device side, when each of the liquid infusion devices is inserted into each of the respective racks.

Abstract: A magnetic linear position sensor comprises a first yoke which is made of soft magnetic material; a first magnet which is placed at the first yoke, and whose surface is the N-pole and is inclined; a second magnet which is placed at the first yoke, and whose surface is the S-pole and is inclined in a direction opposite to the surface of the first magnet and in a direction facing the surface of the first magnet; a second yoke which is placed at a position opposing the first magnet and the second magnet through an air gap and is made of soft magnetic material; and a magnetoelectric transducer which is placed in the air gap.

Abstract: A stator is constructed by winding excitation coils around respective main poles. A rotor is constructed by fixing a first rotor unit, which consists of a pair of rotor cores and a magnetic material sandwiched between the rotor cores, and a second rotor unit, which has the same construction as the first rotor unit, to a rotation shaft. The rotor is assembled to the stator to form an assembled body. The magnet material of the first rotor unit is magnetized in the axial direction by a magnetizing flux passing through a half of the assembled body in the axial direction. The magnet material of the second rotor unit is magnetized in the axial direction in an opposite polarity by a magnetizing flux passing through the remaining half of the assembled body in the axial direction.

Abstract: A two-phase or three-phase claw-pole type rotary machine comprises two or three coaxially arranged single phase rotary machine elements. Each of the rotary machine elements has a magnet rotor, a claw-pole type stator, and an annular stator winding. Claw poles of the stator are divided into a plurality of blocks and are circumferentially separated from one another. A distance between adjacent claw poles of the same polarity in each block is (?0???), substantially, where ?0 is a reference pitch when the claw poles of the same polarity are arranged equidistantly apart from one another in a range of 360°, ?? is ?/2q, or ?/3q and q is a number of claw poles of the same polarity in each block. The first and second rotary machine elements are circumferentially shifted from each other by 90° or 120°.

Abstract: A spring device consists of a coil spring case formed of right, left, back and front side plates and a spring receiving plate, a coil spring having a liner spring property, and a spring urging member for urging the coil spring into the coil spring case. A distance between the right and left side plates of the spring case is set a little larger than an outer diameter of the coil spring. A distance between the back and front side pates of the spring case is set about 1.5 to 2 times larger than the outer diameter of the coil spring, and a length of the spring case is set smaller than a free length of the coil spring. The coil spring is deformed and a non-linear spring property is obtained when the coil spring is urged through the spring urging member.

Abstract: A toroidal-coil multi-phase linear stepping motor includes a cylindrical housing, an axis coaxially arranged inside the housing, a cylindrical element supported by the axis and an armature fixed to the housing around the cylindrical element through an air gap in the radial direction. The axis is fixed to the housing and the cylindrical element linearly moves along the axis. The cylindrical element has toroidal permanent magnets that are alternately magnetized in N pole and S pole in the axial direction. The armature consists of armature units arranged around the axis. Each armature unit has a toroidal coil and a pair of armature yokes that hold the toroidal coil. Each armature yoke has toroidal magnetic teeth on its inner surface. The invention also includes a toroidal-coil single-phase linear reciprocating motor and a cylinder compressor and a cylinder pump using these motors.

Abstract: A stepping motor includes: a stator having main magnetic poles each having small stator teeth on its tip, a core-back portion that connects outer portions of the poles, and windings wound around the poles; and two sets of rotor units that are arranged in an axial direction and face the stator with an air gap therebetween. Each rotor unit consists of two rotor cores that are separated in the axial direction and a magnet sandwiched thereby and magnetized in the axial direction. Each rotor core has small rotor teeth around its outer surface. The rotor cores of each rotor unit are deviated by ½ pitch of the small rotor teeth, and the two rotor units are arranged to make the magnetic polarities of the small rotor teeth of the adjacent two rotor cores identical. A magnet thickness Tm and a rotor core thickness Tc satisfy 0.25?Tm/Tc?0.45.

Abstract: A spring device includes of a coil spring case formed of right, left, back and front side plates and a spring receiving plate, a coil spring having a liner spring property, and a spring urging member for urging the coil spring into the coil spring case. A distance between the right and left side plates of the spring case is set a little larger than an outer diameter of the coil spring. A distance between the back and front side pates of the spring case is set about 1.5 to 2 times larger than the outer diameter of the coil spring, and a length of the spring case is set smaller than a free length of the coil spring. The coil spring is deformed and a non-linear spring property is obtained when the coil spring is urged through the spring urging member.