Abstract: A gas blending system for use with a medical ventilator blends a pressurized gas with ambient air for delivery to the ventilator in response to the ventilator's demand for gas during the gas intake phase of its cycle. The system comprises a demand valve that discharges a flow of the pressurized gas in proportion to the demand applied to its outlet. The demand valve outlet is coupled to a first inlet of a blending valve, a second inlet of which is open to the atmosphere. The blending valve has a blended gas outlet adapted to be coupled to the ventilator. The total demand applied by the ventilator to the blended gas outlet is transmitted to the first and second inlets. A proportioning mechanism in the blending valve adjusts the demand that is transmitted to the demand valve outlet through the blending valve first inlet as a percentage of the total demand applied to the blended gas outlet.

Abstract: Wall murals are readily achieved by the do-it-yourself exponent with the use of apparatus contained in a kit. The kit of the invention includes a case which has brackets enabling the case to be supported on a wall or stabilized on a table or the like. Inside the case is a projector and a slide transparency bearing an outline of the intended mural in which different areas are designated according to the color intended for that area. The case includes a series of paint pots each containing a different corresponding colored paint and each bearing the corresponding designation of the paint color. To produce the mural the image of the slide is projected onto the wall and the different areas are painted with a different colored paint in accordance with the indicated designations.

Abstract: A squeeze-actuated syringe includes a longitudinal body adapted to receive a collapsible ampul. A handle is attached by a hinge to one end of the body, the other end of which is adapted to receive a fitting on the ampul. The handle has a projection or pad on its underside in opposed relationship to the ampul received in the body. When the handle is squeezed toward the body, the ampul is compressed, discharging its contents through a hypodermic needle or the like attached to the fitting. A ratcheting lock mechanism on the handle and the body defines a plurality of selectable detented positions for the handle relative to the body. The handle can be stopped at any selected detented position, thereby allowing the contents of the ampul to be discharged in intermittent stages. In one embodiment, the ratcheting lock mechanism comprises a first serrated member on the body which is co-engageable with a second serrated member on the handle.

Abstract: A guitar stand has a main body or base which forms an interior cavity. An adjustably extendable elongated neck member carrying a 270-degree pivotable yoke, for supporting the neck of a guitar, is mounted into the cavity. The base includes substantially L-shaped extensions forming channels into which foldably extendable legs are mounted. The legs are substantially concealed and non-obtrusive when they are folded away into the channels, as for transportation or storage.

Abstract: A method of manufacture of objects by consolidation of powdered metals, alloys, ceramics, or their mixtures is disclosed. The method comprises the steps of preparing a shaped, preferably ceramic, shell, placing it inside a metal or ceramic can, filling both the shell and space between the shell and the can with powder, outgassing and sealing the can if necessary, heating the full can and pressing it to consolidate the powder into a dense form; and separating the densified object within the shell from the densified shapes between the shell and the can. During pressing, the ceramic shell does not consolidate or bond to the surrounding powder, thus acting as an easy parting surface as well as being a shape defining container for the object being consolidated. The method permits easy definition of desired shell shape and permits manufacture of complex shaped, fully densified objects in near-net-shape form.

Abstract: A tissue expander, of the type containing within the interior of its expandable shell an injection reservoir self-sealing to punctures by a hypodermic needle, is disclosed. The tissue expander includes a reinforcing member or insert which is substantially more rigid than the expandable shell, is larger than the injection reservoir, and is mounted to the expandable shell with its center substantially at the apex of the shell and substantially superimposed with the center of injection reservoir. The reinforcing member substantially prevents folding of the expandable shell over the injection reservoir and thereby substantially prevents inadvertent puncture of the expandable shell by a needle which is directed into the injection reservoir. Magnetically detectable material is mounted into the injection reservoir to enable an externally applied magnet locator to find the injection reservoir when the entire tissue expander assembly is temporarily implanted in a patient.

Abstract: A pair of forceps has a shank and a pair of resilient arms. A groove, running along the inner face of each arm and communicating with a channel in the shank, accommodates a fiber optic cable which provides illumination at the tip of the forceps for items handled by the forceps. The use of the forceps is particularly suitable for manipulating an artificial lens in a human eye because the surface of the lens is illuminated to make it stand out against the liquid of the eye which has substantially the same refractive index as the lens.

Abstract: An anti-friction worm-worm gear type speed reducer torque converter is disclosed. The speed reducer has a rotatably mounted worm gear adapted to mesh with a rotatably mounted worm incorporating a plurality of circulating rolling elements. In one embodiment, the configuration of the spiral thread of the worm is such that the balls incorporated in the load carrying side face of the spiral thread provide a substantially continuous substantially spiral shaped contact line with the load transmitting tooth of the worm gear. This is accomplished by providing the helicoid spiral thread of the worm with a flat, approximately bell shaped profile in the radial direction, with reference to the longitudinal axis of the worm, and by gradually modifying the trapezoidal dimensions of the spiral thread in axial cross-section.

Abstract: A system for measuring the course length of a well bore uses a probe containing accelerometers to generate a first output signal indicative of the time rate of change of the probe's velocity as it travels through the bore. The probe also contains two casing collar locators separated by a measured distance. A microcomputer in the probe integrates the first output signal twice with respect to time to generate a course length value indicating the total distance travelled by the probe. The microcomputer also calculates a computed distance value by integrating the first output signal twice with respect to time over the time interval between the generation of first and second joint-indicative signals as a result of the successive passage of one pipe joint by the two casing collar locators. The computed distance value is compared by the microcomputer with a stored distance value representing the measured distance between the casing collar locators.

Abstract: A fastener assembly, having a threaded male and female member, is disclosed. One of the members has substantially conventional threads and the other member has two threaded portions rotationally offset relative to one another. Direction of the offset determines whether a compressive or tensile preload force occurs in the assembled fastener. Magnitude of the preload force is controlled by the extent of the offset. One of the threaded portions includes at least two, preferably about four, tapered threads which permit gradual distribution of the preload force and thereby prevent plastic deformation of the threads. The assembled fastener is substantially vibration proof, and, due to the well controlled permanent preload force, is highly fatigue resistant.

Abstract: A rotary motion linear actuator is disclosed which is capable of substantial backlash or lost motion free operation. The rotary motion linear actuator includes a ball nut body having interior helical (Archimedes type) spiral grooves to contain a plurality of balls between the ball nut body and a rotatable shaft upon which the ball nut body is mounted in a substantially concentric relationship. A spiral slot is disposed in the ball nut body substantially parallel with the spiral grooves so as to effectively render the ball nut body capable of torsional deformation about its longitudinal axis, in analogy to a coil spring. The ball nut body carries an exterior torque tube or like mounting body, which holds the ball nut body in a predetermined torsionally deformed state. The balls disposed between the shaft and the ball nut body are therefore biased with a predetermined pre-load against the shaft, and the rotational axes of the balls are inclined relative to the longitudinal axis of the shaft.

Abstract: A shutter or blind assembly comprises a plurality of verically-spaced, horizontally-extending slats rotatably mounted between a pair of opposed vertical side rails. Each of the side rails has a plurality of vertically-spaced, horizontal grooves extending rearwardly from the forward edge thereof, and each of the grooves has a downwardly-extending notch formed contiguously therewith. Each slat has a dowel at each end, and the dowels on each slat are removably received in an opposed pair of grooves so as to be rotatably seated in an opposed pair of notches. A vertical tilt bar interconnects most or all of the slats. The tilt bar comprises an inner member which is removably retained in an outer member. The inner member removably receives a vertically-spaced plurality of hooks or eyelets that are attached to the slats. Each slat is individually removable from the assembly by separating the inner and outer tilt bar members, allowing the hooks or eyelets to be removed from the inner member.

Abstract: A protective device for a motor vehicle comprises an elongate guard member having a longitudinal axis oriented substantially parallel to the longitudinal axis of the vehicle. The guard member is variable in length between a contracted position and an extended position. A pivot assembly operatively connects the guard member to the underside of the vehicle so that the guard member can be moved between a lower position and an upper position along the side of the vehicle. As the guard member is raised to its upper position, the pivot assembly acts on the guard member to extend its length to its extended position, while lowering the guard member causes the pivot assembly to contract the guard member to its contracted position. The pivot assembly includes front and rear "L"-shaped pivot members each having a first arm rotatably mounted in a tube attached to the underside of the vehicle, and a second arm pivotably connected to a telescoping, sliding portion of the guard member.

Abstract: An abrasion resistant pipe bend or elbow for slurry pipelines is disclosed. The bend or elbow has a wall of enlarged thickness disposed in the exterior of the turn of the fluid flow, in the area where impingement of the interior wall of the elbow by solid particulate material is most likely to occur. The wall of enlarged thickness includes a plurality of spaced protrusions which form a plurality of indentations or pockets. Openings of the pockets are disposed in substantial alignment with the instantaneous trajectory of solid particulates transported in the slurry. The pockets become filled with captured solid particles when slurry is transported through the elbow. The particles act as a shield or buffer against further bombardment of the wall of the elbow by the particles. Leading edges of the protrusions optionally have a cladding of an abrasion resistant material, such as a hardfacing composition, and are disposed to have a favorable, usually large, impact angle with the solid particles.

Abstract: A flexible container comprises a receptacle divided into two chambers by an openable, fluid-tight barrier formed between the interior surface of the receptacle and the exterior surface of a hollow member contained in the receptacle. The barrier is maintained closed by a removable sealing band applied around the exterior of the receptacle. The removal of the band allows the wall surface of the receptacle to separate from the exterior surface of the hollow member, thereby opening a passage between the two chambers.

Abstract: Apparatus for the practice of sand trap golf shots comprises a receptacle formed from one or more pieces of foldable sheet material. In one embodiment, the sheet material is supported in the configuration of a receptacle by being placed inside of a tray. In another embodiment, the material is attached to a frame for support. One piece of material forming the receptacle has an integral extension which, when unfolded, extends outwardly from one or more sides of the receptacle to form an apron. The receptacle is filled with sand or a suitable substitute. A golfer can practice hitting balls out of the sand. The sand scattered by the golfer's swings falls on the apron, which can then be lifted over the receptacle to return the sand to the receptacle's interior. When the apparatus is not in use, the apron is simply folded up over the sand, thereby protecting the sand from the elements. A golf shot aiming device is advantageously included in the apparatus.

Abstract: A removable cover for the engine compartment in a cab-over-engine motor vehicle comprises a frame that fits around the engine access opening in the cab of the vehicle, and an inflatable cover element sealingly attached around its peripheral edges to the frame. The cover element, when inflated, has an aperture or passage through which a hose or the like can be inserted to clean the engine. The cover element is wholly or partially transparent to allow the user to observe and direct the hose. The frame is hinged so that the cover can be folded for easy storage when the cover element is deflated.

Abstract: A humidifier system including a humidifier chamber and heater assembly, microprocessor based control circuitry, and a housing for the control circuitry. The humidifier system is adapted to provide air at nearly 100 percent relative humidity and at a predetermined temperature (e.g. 35.degree. C.) to a medical (e.g. critical care) patient. The humidifier chamber includes a continuous spiral heat exchange path which extends between a vapor storage chamber and an outlet of the humidifier chamber at which an air heating tube is connected, so that outgoing air can be delivered to the patient. The vapor storage chamber is interfaced with a ventilator source of incoming air and a relatively small reservoir in which a supply of water is boiled by the heater assembly for providing vapor saturated air from the vapor storage chamber to the heat exchange path.

Abstract: A dry dock having flotation chambers on two opposite sides of the load-carrying platform is submerged by flooding the flotation chambers. A reversible air pump is used to raise the dry dock by first blowing water out of the chambers then sucking water from the platform into the chambers and then again blowing water out of the chambers. The structure of the dry dock allows it to be used also as a submergible barge.

Abstract: A gas blending system includes a proportional mixing valve having a valve element movable between first and second limits of travel corresponding to a minimum and maximum percentage, respectively, of one of the gases in the blended mixture. The position of the valve element is detected by a detection mechanism, producing a position signal inputted to a microcomputer. The microcomputer also receives a control signal representing a desired percentage of one of the gases to be blended. The microcomputer calculates a desired valving element position as a function of the value of the control signal, and generates a drive signal as a function of a comparison made by the microcomputer between the detected valve element position and the desired position. A motor drives the valve element to the desired position in response to the drive signal.