Abstract: In a rotation preventing mechanism in which a ball (26) is interposed between a pair of races (24, 25) each having a rolling groove surface (24c, 25c) receiving the ball, the rolling groove surface has a bottom portion (24c3, 25c3) of a radius of curvature which is greater than each of those of an outer peripheral portion (24c1, 24c2) and an inner peripheral portion (25c2, 25c2). Each of the radii of the outer peripheral and the inner peripheral portions is approximate to and greater than the radius of the ball. The races are attached to a front housing (10b) and a movable scroll member (20) which carries out orbital motion along a predetermined orbit with respect to the front housing. The rolling groove surface has an annular shape corresponding to the predetermined orbit.

Abstract: A scroll type fluid displacement apparatus comprises a housing having an inlet port and an outlet port. An orbiting scroll has a circular end plate from which a spiral element extends and a pair of parallel grooves formed on the circular end plate. An Oldham coupling mechanism is disposed between the fixed scroll and the housing and includes a ring and a supporting member fixedly secured to the housing. The supporting member has a pair of parallel grooves formed on one end surface thereof. The ring has a pair of first parallel key portions and a pair of second parallel key potions. The second key portions are axially offset from the first key portions. The first key portions engage the grooves of the circular end plate of the orbiting scroll while the second key portions engage the grooves of the supporting means.

Abstract: A scroll type fluid displacement apparatus having a rotation regulating mechanism. The rotation regulating mechanism comprises a crank pin which inserts into an eccentric hole of a bushing. The crank pin has at least one portion which regulates rotation of the crank pin within the eccentric hole thereby regulating an angle of swing of the bushing around a center of the crank pin.

Abstract: A scroll type fluid displacement apparatus, in particular, a scroll type compressor, is disclosed. The apparatus includes a pair of scroll members at an angular and radial offset for forming fluid pockets, each scroll member having a spiral element. A bypass hole is provided on a wall of at least one of the spiral elements of the scroll members for communicating between the fluid pockets and a suction chamber. A valve mechanism, which operates in a radial direction, controls the opening and closing of the bypass hole. The valve mechanism is responsive to the rotational motion of the scroll members and/or the pressure in at least one of the fluid pockets. When the apparatus is driven at excessive speed, the valve mechanism operates in response to centrifugal force to open the bypass hole. The compressed fluid in the fluid pockets then is released into the suction chamber through the opened bypass hole, and the compression capacity is reduced to a proper value.

Abstract: A scroll type fluid displacement apparatus, in particular, a scroll type compressor, is disclosed. The apparatus includes a pair of scroll members at an angular and radial offset for forming fluid pockets, each scroll member having a spiral element. A bypass hole is provided on a wall of at least one of the spiral elements of the scroll members for communicating between the fluid pockets and a suction chamber. A valve mechanism, which operates in a radial direction, controls the opening and closing of the bypass hole. The valve mechanism is responsive to the rotational motion of the scroll members and/or the pressure in at least one of the fluid pockets. When the apparatus is driven at excessive speed, the valve mechanism operates in response to centrifugal force to open the bypass hole. The compressed fluid in the fluid pockets then is released into the suction chamber through the opened bypass hole, and the compression capacity is reduced to a proper value.

Abstract: A scroll type compressor including a fixed scroll and an orbiting scroll is disclosed. The fixed scroll includes a first circular end plate from which a first spiral wrap extends and the orbiting scroll includes a second circular end plate from which a second spiral wrap extends. The spiral wraps interfit such that an axial gap is maintained between the axial end surface of each wrap and the axial surface of the adjacent end plate, at a central location of the scrolls. The fixed end plate is supported in the compressor housing at a radially intermediate portion of the axial end surface opposite the spiral wrap, and at a radially outer portion by an annular ridge formed on the inner surface of the compressor housing.

Abstract: The present invention relates to a scroll type fluid displacement compressor, and more particularly, to an axial sealing mechanism for sealing the scrolls in an axial direction. A scroll type fluid displacement compressor includes a housing, a pair of scrolls each comprising an end plate and scroll element projecting from one surface of the end plate. Both scroll elements are interfitted at an angular and radial offset to make a plurality of line contacts. A groove is formed on the end surface of each scroll element and a seal element is placed within each groove. The axial thickness of one seal element is equal to or greater than the depth of the groove. The axial thickness of the other seal element is less than the distance between the bottom surface of the other groove and the end plate of the opposing scroll.

Abstract: In a high-speed video camera, a light beam from a main lens (3) is split into a plurality of light beams having identical optical information, and then these plurality of light beams are intermittently transmitted to different positions of an imaging device (11) in sequence. As a beam splitter may be used a multi-lens assembly (8) or a prism (14) having a plurality of light-receiving surfaces. In order to intermittently transmit the plurality of light beams in sequence to the imaging device, an image-selecting rotary shutter (12) having a fan-shaped opening (12a) is used. This shutter (12) and another shutter (5) for defining exposure time are synchronized with each other, and also synchronized with a vertical sync signal from a sync generator. In order to establish synchronization an adjustable delay circuit (38) is used.

Abstract: A thermal transfer type printing apparatus comprises a paper feeding mechanism, an ink ribbon traversing over a printing paper, a thermal printing head, a head moving mechanism, and a control circuit. The ink ribbon is divided into at least three colors in a width direction thereof and has first through third ink parts extending in a longitudinal direction thereof. The thermal printing head is arranged at such a location that the ink ribbon is interposed between the head and the printing paper. The head comprises first through third heating element groups respectively opposing the first through third ink parts of the ink ribbon, and the first through third heating element groups each has at least one heating element which is selectively heated depending on a color information signal which is indicative of a color picture or the like which is to be printed.

Abstract: A thermal printing head with first through n-th heating elements with respect to at least one printing line, where n is an integer, and an i-th heating element among the first through n-th heating element has an area of M/2.sup.i when a total area of one picture element is represented by M, where i is an arbitrary integer. The first through n-th heating elements are arranged at positions such that printing areas of the first through n-th heating elements do not overlap each other when the first through n-th heating elements carry out printing with respect to one picture element.