Abstract: A semi-submersible platform supported on columns with pontoons extending between and outboard of the columns. Damper plates are provided by flat surfaces either on top of the outboard section of the pontoons or by plates positioned on the columns above the pontoons to provide heave and pitch stabilization and motion phase control in relation to the wave action such that when the platform is in the drilling mode the heave phase of the platform is approximately one hundred eighty degrees out of phase with wave action and in the survival mode heave action of the platform is substantially in phase with wave action, such that the platform will ride with the storm waves allowing the use of shorter columns than the current art.

Abstract: A combination offshore drilling rig which combines the desirable features of a slot-type drilling rig and a cantilever-type drilling rig while eliminating the limitations and undesirable features associated with either type of such rigs. The combination offshore drilling rig mounts the derrick and drilling equipment on a movable cantilever structure which may be positioned over a slot of sufficient area to permit the drilling operation to be carried out through the slot or may be moved outboard of the peripheral boundary of the rig hull to perform a drilling or workover operation outside the peripheral boundary of the rig hull.

Abstract: A venetian blind which may have a conventional head rail, tilt rod, ladder tapes and slats, wherein a framework is mounted in the head rail and rotatably passes the tilt rod, an arm extends generally radially from the tilt rod for rotation with the latter, and a pair of stop members are selectively positionable relative to the framework in the path of arm movement for limiting arm rotation in opposite directions. The slats may be provided with reflective and absorptive surfaces to cooperate with the limiting positions of tilt for reflecting and absorbing heat in accordance with the seasons or other desiderata.

Abstract: A venetian blind including end rails and slats all extending in parallelism with each other and lying in a cylindrical or arcuate surface, and a stay extending through the slats and between the end rails to maintain the venetian blind in its arcuate configuration.

Abstract: A spring clip shaft connection wherein a shaft includes a transverse hole spaced inwardly from one end of the shaft, a generally U-shaped body having a leg formed with longitudinally extending proximate and distal leg portions laterally offset from each other by an intermediate leg portion, and an arm extending from the body longitudinally of the leg, the leg being insertable through the hole for location of the intermediate leg portion in the hole with the distal and proximate leg portions on opposite sides of the shaft, and the arm being resiliently snap engaged into a recess in the leg.

Abstract: A cord lock for mounting in the headrail channel of a venetian blind including a hollow structure seated on the bottom wall of the channel and having a lower opening for communication through the channel bottom wall, front and back shoulders externally on the hollow structure engaging upper regions of the headrail channel to retain the hollow structure in position in the channel, a cord guide in the hollow of said structure, and a jamming element movable in the hollow structure upwardly toward and downwardly away from the cord guide for jamming and releasing a lift cord between said guide and jamming element.

Abstract: A cord lock for up to eight lift cords including an openwork, grid-like structure adapted to seat on the bottom wall of a headrail channel over a bottom wall opening; the grid-like structure including intersecting longitudinal and transverse members; upwardly facing formations for retaining engagement beneath inturned lips of the channel; a depending formation for restraining engagement through the channel bottom wall opening; generally vertically extending way means formed in the longitudinal members, and a transversely extending jamming element freely shiftable up and down in the way means into and out of cord jamming relation with an adjacent cross member.

Abstract: An improved barge hull for offshore drilling rigs is disclosed. The invention comprises a channel in the bottom of a barge hull extending from the bottom of said barge hull to the back of said barge hull for directing the flow of water under said barge hull to the back of said barge hull in order to disrupt the relative hydrodynamic stability of a body of water immediately behind said barge hull and thereby decrease the towing resistance of said barge hull.

Abstract: A support for mounting a tilt rod in the head rail of a venetian blind, including a bottom wall or base for resting on the bottom wall of a head rail with depending retainer means for snap retaining engagement through the bottom of the head rail, a pair of spaced side or end walls upstanding from the base and having aligned cut-outs extending downwardly for rotatably receiving a tilt rod, and resiliently deflectable projections extending into at least one cut-out for snap passage therebetween and releasable retention thereby of a tilt rod in the associated cut out.

Abstract: An apparatus for restricting the lateral motion of a pipe column extending upward from the bottom of a body of water to a point above the surface of the water. The apparatus finds its preferred use as a drive pipe stabilizer for a cantilever-type offshore drilling barge or the like.

Abstract: A method and apparatus for correcting bow in crowned strip wherein a pair of complementary rolls receive the crowned strip, one roll of the pair being adjustable toward the other, and the assembly being adjustable transversely of the path of strip movement to correct bow.

Abstract: A tilt limiting mechanism for a venetian blind including a mounting member non-rotatably positioned in the blind head rail and providing a guideway partially about the tilt rod, a radial extension on the tilt rod extending into the guideway for swinging movement therealong upon tilt rod rotation, and stop members positioned in the guideway to engage the radial extension and limit rotative movement of the tilt rod.

Abstract: A tilter operating mechanism for a venetian blind including a stub shaft depending from a head rail and rotatable to tilt the blind slats, a cross piece or pin on the lower stub shaft end, and an operating rod or wand having on one end a resilient clip for snap assembly with the cross piece, so that the wand is rotatable in opposite directions to effect desired slat tilting.

Abstract: A venetian blind including a rotary tilt rod and tilt rod operator, wherein a yieldable or slip coupling is interposed in motion transmitting relation between the operator and tilt rod to disengage the same upon excessive torque, the coupling including driving and driven elements respectively connected to the operator and tilt rod and having separable interfitting formations configured to effect driving engagement and urge the elements and formations apart, and a resilient device yieldably urging the elements and formations toward each other.

Abstract: A bracket for a venetian blind headrail comprising a side opening box-like structure having means for mounting to a window frame, a swingably openable front cover on the structure, and a forward upstanding retaining lip on the bottom wall for retaining the supported end of a headrail on the bottom wall.

Abstract: A venetian blind having a top position lock wherein a pull cord extends over and depends from a cord guide between the latter and a freely upwardly shiftable jam member which engages the depending pull cord. The pull cord urges the jam member downwardly away from the guide upon upward slat movement, and the pull cord urges the jam member upwardly into jammed engagement with the cord guide upon downward slat movement. Detent means holds the jam member downwardly except in the top slat position, so that jamming action only occurs with the slats fully raised.