381results about How to "Reduce air gap" patented technology

A blood pump comprises a pump housing; a rotor positioned in the housing and comprising an impeller having a hydrodynamic surface for pumping blood; and a motor including a plurality of magnets carried by the impeller, plus a rotor stator, including an electrically conductive coil located adjacent to or within the housing. The impeller comprises radially outwardly extending, bladelike projections that define generally longitudinally extending spaces between the projections. The shape of the projections and the spaces therebetween tend to drive blood in the spaces in an axial direction as the impeller is rotated. The spaces collectively have a total width along most of their lengths at the radial periphery of the rotor, that is substantially equal to or less than the collective width of the projections along most of their lengths at the radial periphery. Thus, the bladelike projections are thicker, achieving significant advantages.

An embodiment of the present invention provides a stepping actuator, comprising a suspended membrane comprising a plurality of movable electrodes connected by plurality of spring hinges to a payload platform; and anchors connecting said membrane to a substrate, said substrate comprising a plurality of fixed electrodes; wherein said movable electrodes of said suspended membrane and said fixed electrodes from said substrate form parallel-plate electrostatic sub-actuators.

An optical-lens-set includes a first lens element of positive refractive power, a second lens element of an image surface with a concave portion near the optical-axis, no air gap between a third lens element and a fourth lens element, at least one of an object surface and an image surface of a fifth lens element being aspherical, both an object surface and an image surface of a sixth lens element being aspherical so that the total thickness ALT of all six lens element, the distance TL from an object surface of the first lens element to the image surface of the sixth lens element and total five air gaps AAG satisfy ALT / AAG≤4.5 or TL / AAG≤5.5.

The invention relates to a magnetic trigger mechanism at least comprising a yoke having an armature opening, in which yoke an armature is placed, which armature is coaxially surrounded by at least one section of the coil body having at least one excitation coil and which is acted on by the force of a preloaded spring element and which remains in a first end position due to the magnetic retaining force of a permanent magnet when current is not flowing through the excitation coil, the permanent magnet being arranged in the area of the first end of the armature together with a base extending between the armature and the permanent magnet, and the second end position of the armature being achieved by means of a brief flow of current through the excitation coil together with the accompanying lowering of the magnetic retaining force and the spring force, which is effective then. The invention is characterized in that the first end of the armature, which first end faces away from the armature opening, is guided in the coil body in a centered manner, and the second of the armature, which second end faces the armature opening, is likewise guided in a centered manner by means of a centering ring centered in the coil body, the highly permeable centering ring lies against the yoke at the armature opening and can move radially relative to the yoke, the base is centered in the coil body, the centering ring together with the coil body ensuring that the armature lies flat in the area of the first end without tipping and always guaranteeing maximum retaining forces due to the armature lying flat, the spring element having a larger diameter than the armature, and the magnetic flux commutating upon triggering from a series connection to a parallel connection.

In the present invention, each tooth (22) has a tooth body part (24) and a tooth tip part (25). A pair of slant parts (26) project from both circumferential sides of the tooth tip part (25). A tip surface (27) is formed on the inner diameter-side end surface of the tooth tip part (25) so as to face a magnet (15) across an air gap (g). A recessed groove part (28) extending in an axial direction is disposed at the center of the tip surface (27). The depth (d) of the groove part (28) is set in the range of 0 < d <= (Lx-Rt) / 3, and the width (Wg) is set in the range of Wt > Wg >= Wt / 2 (Lx: distance from the center of a rotor to a tooth-slant intersection (X), which is the intersection of an extended line (P) from a circumferential side surface of the tooth body and an extended line (Q) from the slant surface of the slant part; Rt: radius of the inner diameter of the tooth tip surface; Wt: width of the tooth body).