Abstract: A motor control device according to the present invention includes a motor driving unit for driving a motor, a current vector controller, a magnetic-flux weakening current command generator, and one of a target command limiter and a q-axis current command limiter. The current vector controller controls a current of the motor by separating the current into a d-axis current and a q-axis current orthogonal to each other, in accordance with a target command value from the outside. The magnetic-flux weakening current command generator generates a d-axis current command to control the amount of the d-axis current, based on one of differences, i.e. a difference between a first predetermined reference value and the absolute value of a voltage command from the current vector controller to the motor driving unit and a difference between a second predetermined reference value and a q-axis component of the voltage command.

Abstract: A phase-shift detection circuit detects a phase shift in motor driving, using pulse-shaped position detection signal Rd and measurement signal Ms. The position detection signal is based on sensor signal Hs from a position sensor disposed in a motor. The measurement signal is based on the induced voltage from windings. The phase-shift detection circuit includes a level difference calculator and a phase-shift calculator. The level difference calculator calculates a level difference between the level of measurement signal Ms at a rising timing of position detection signal Rd and the level of measurement signal Ms at a falling timing thereof. The phase-shift calculator calculates the amount of phase shifts based on the level difference.

Abstract: The connection structure of flexible boards permits efficient positioning and connecting of a plurality of flexible boards arranged one over the other in a camera by providing a pair of pin elements in a protruding condition in a base portion and forming on one of the pin elements a groove to be engaged with flexible boards. A lens device includes a base metal sheet of metal and pin elements of plastic provided in a protruding condition in the base metal sheet. The pin element has a groove formed on an outer periphery surface of the opposite side to the pin element. A main flex or a shutter flex has holes formed therein, into which the pin elements are to be inserted. A spacing between the holes is formed a little smaller than a spacing between the pin elements.

Abstract: The lens device is capable of preventing a guide member from being disengaged from a guide groove with a simple construction, in which a projecting thread portion is formed on a sidewall of the guide groove for guiding a lens barrel in a straight motion and a recessed thread portion to be engaged with the projecting thread portion is formed on a sidewall of the guide member that is guided by the guide groove. A straight guide groove along the optical axis is formed on an inner peripheral surface of a first lens barrel, and a straight guide projection that is guided by the straight guide groove is formed on a second lens barrel. On a sidewall of the straight guide groove, a projecting thread portion is formed and on a sidewall of the straight guide projection, a recessed thread portion to be engaged with the projecting thread portion is formed.

Abstract: The lens device performs focusing adjustment by moving a lens holding frame for a focusing lens in the direction along an optical axis by a lead screw device, in which a nut member is engaged with an engaging portion formed on a nut mounting portion of the lens holding frame and the nut member is positioned against the nut mounting portion, thus improving forwarding precision of the lead screw device to perform focusing operation with high precision. The nut member is engaged with a protruding portion formed on the nut mounting portion of a third lens frame in a third lens frame for a third lens, which is a focusing lens, and the nut member is positioned against the nut mounting portion, thus preventing inclination, misalignment or deformation of the nut member against the nut mounting portion. Thereby the forwarding precision of the lead screw device is improved; accordingly, the focusing operation can be performed with high precision.

Abstract: Guide grooves are formed on the inner periphery of a first lens barrel along an optical axis, and guide couplers are coupled with the guide grooves to guide the first lens barrel along the optical axis. Inclined parts are formed on both sides of the guide grooves, and inclined parts are formed on both sides of the guide couplers. Thus, the guide couplers do not easily come off from the guide grooves even if a pressure is applied to them.

Abstract: The lens device is capable of preventing a guide member from being disengaged from a guide groove with a simple construction, in which a projecting thread portion is formed on a sidewall of the guide groove for guiding a lens barrel in a straight motion and a recessed thread portion to be engaged with the projecting thread portion is formed on a sidewall of the guide member that is guided by the guide groove. A straight guide groove along the optical axis is formed on an inner peripheral surface of a first lens barrel, and a straight guide projection that is guided by the straight guide groove is formed on a second lens barrel. On a sidewall of the straight guide groove, a projecting thread portion is formed and on a sidewall of the straight guide projection, a recessed thread portion to be engaged with the projecting thread portion is formed.

Abstract: The connection structure of flexible boards permits efficient positioning and connecting of a plurality of flexible boards arranged one over the other in a camera by providing a pair of pin elements in a protruding condition in a base portion and forming on one of the pin elements a groove to be engaged with flexible boards. A lens device includes a base metal sheet of metal and pin elements of plastic provided in a protruding condition in the base metal sheet. The pin element has a groove formed on an outer periphery surface of the opposite side to the pin element. A main flex or a shutter flex has holes formed therein, into which the pin elements are to be inserted. A spacing between the holes is formed a little smaller than a spacing between the pin elements.

Abstract: The lens device performs focusing adjustment by moving a lens holding frame for a focusing lens in the direction along an optical axis by a lead screw device, in which a nut member is engaged with an engaging portion formed on a nut mounting portion of the lens holding frame and the nut member is positioned against the nut mounting portion, thus improving forwarding precision of the lead screw device to perform focusing operation with high precision. The nut member is engaged with a protruding portion formed on the nut mounting portion of a third lens frame in a third lens frame for a third lens, which is a focusing lens, and the nut member is positioned against the nut mounting portion, thus preventing inclination, misalignment or deformation of the nut member against the nut mounting portion. Thereby the forwarding precision of the lead screw device is improved; accordingly, the focusing operation can be performed with high precision.

Abstract: Guide grooves are formed on the inner periphery of a first lens barrel along an optical axis, and guide couplers are coupled with the guide grooves to guide the first lens barrel along the optical axis. Inclined parts are formed on both sides of the guide grooves, and inclined parts are formed on both sides of the guide couplers. Thus, the guide couplers do not easily come off from the guide grooves even if a pressure is applied to them.