Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A prenatal listening device includes first and second handheld units. The first handheld unit includes a cup-shaped body that defines an acoustic cavity. The first handheld unit further includes a microphone mounted to the body in the acoustic cavity to capture fetal sounds collected by the acoustic cavity. The second handheld unit is spaced from and communicatively coupled to the first handheld unit. The second handheld unit includes a controller to process signals from the microphone indicative of the captured fetal sounds, a housing to enclose the controller, and an audio output to reproduce the captured fetal sounds.

Abstract: A child motion device has a frame assembly configured to rest on a floor surface. A support arm assembly is coupled to and cantilevered from part of the frame assembly above the floor surface. A child supporting device is supported by the support arm assembly. A bounce mechanism of the device is employed to reciprocally bounce the child supporting device above the floor surface.

Abstract: A child motion device has a frame assembly configured to rest on a floor surface. A support arm assembly is coupled to and cantilevered from part of the frame assembly above the floor surface. A child supporting device is supported by the support arm assembly. A bounce mechanism of the device is employed to reciprocally bounce the child supporting device above the floor surface.

Abstract: A child containment structure includes a floor and a sidewall connected to the floor and defining a unitary structure with the floor. The sidewall includes at least one side panel formed at least partially of an air-restricting material and at least one ventilation panel positioned between the floor and the side panel. The ventilation panel has a maximum height smaller than that of the side panel, and the ventilation panel permits air flow between an interior of the containment structure and an exterior of the containment structure along a sleeping surface of the child containment structure.

Abstract: A changing table for use with a playard includes a platform that is sized to support a child and at least one changing table mount arranged relative to the platform to releasably engage the platform to the playard. The changing table mount includes a release actuator. When the changing table is engaged with the playard, the changing table is configured to remain engaged with the playard when a force of less than or equal to 25 pounds is applied to a location on the changing table other than the release actuator.

Abstract: A changing table is provided for engagement to a playard that includes at least one top rail. The changing table includes a support structure and a platform coupled to the support structure, the platform being sized to support a child. The changing table is configured to engage the playard. The changing table is configured so that, when the changing table is engaged to the playard, and an opening is defined at least in part by a portion of the changing table and a nearest top rail, a portion of the opening in a direction normal to the nearest the top rail is at least 9 inches.

Abstract: A bassinet and changing table assembly includes a frame, a changing table mounted to the frame, and a bassinet releasably mounted to the changing table and/or the frame so that the bassinet is positioned over the changing table. Hence, the diaper changing activity is separated from the child sleeping area.

Abstract: A child sleeping assembly includes a floorboard, an adjustable panel movably connected to the floorboard to move between a reclined position and an inclined position, a frame mounted to the floorboard, and a fabric enclosure mounted to the floorboard and the frame. The fabric enclosure has a sidewall and floor that defines an enclosed child sleeping area. The sidewall encircles the child sleeping area. The child sleeping assembly also can include an adjustment element connected to the floorboard and configured to travel in an adjustment track of the panel to control positioning of the panel between the reclined position and the inclined position.

Abstract: A collapsible frame structure for a playard. The collapsible frame structure includes a plurality of legs, and a plurality of cross members arranged so that at least one cross member extends between, and is pivotally connected to, respective adjacent legs to form a side of the playard. The frame structure also includes a plurality of slider joints, each slider joint slidingly engaging a respective one of the legs, and a plurality of pivot joints, each pivot joint on a respective one of the legs. The frame structure also includes at least one latch mechanism configured to selectively engage at least one of the slider joints with its respective leg, wherein each cross member is mounted to the respective adjacent legs by the slider joint on a first of the respective adjacent legs and by the pivot joint on a second of the respective adjacent legs.

Abstract: A collapsible frame structure, movable between an open arrangement and a folded arrangement, includes a plurality of legs, a plurality of cross members arranged in pairs, a plurality of slider joints and pivot joints, and at least one latch mechanism. Each pair of cross members is located between respective adjacent legs to form sides of the collapsible frame structure that define an interior of the collapsible frame structure. Each slider joint slidingly engages a respective one of the legs and pivotably attaches to two adjacent cross members. Each pivot joint is at a respective one of the legs to pivotably attach two adjacent cross members. The latch mechanism, which is mounted to another frame component of the collapsible frame structure, remains so mounted in both the open arrangement and the folded arrangement. Nonadjacent legs and nonadjacent sides of the collapsible frame structure remain unconnected across an interior of the collapsible frame structure.

Abstract: A system for determining and indicating the position of a finger removes the requirement for a conventional keyboard when providing information to a processor. Various embodiments of the present invention include combinations of ultrasonic, electromagnetic, and optical transducers and devices mounted on various locations of a user's hands and fingers. A character grid, or template, is also included to allow a user to select characters on the grid. The location of a particular finger is used to determine which keyboard character and/or control character on the character grid is being selected. A pair of glove like devices mounted on a user's hands have transducers mounted on the fingers. These transducers include piezoelectric film ultrasonic transducers. The transducers may be mounted on the fingertips of the user, on around the finger like a ring. Because the position of each finger is determined by the system, the character grid is not required to supply this information to the processor.

Abstract: A light collecting and focusing device for an ultrasonic digitizer has a conical tip and an infrared transparent polycarbonate light pipe. Infrared signals received by the conical tip are optically coupled to the photodiode through the light pipe. This device allows the use of a single photo diode mounted on the digitizer for receiving infrared signals from emitters that are not in the direct line of sight with the photodiode. Furthermore, optical coupling between the source of the infrared signals and the photodiode is maintained regardless of the orientation of the digitizer about its access.

Abstract: In the charging of a valve-regulated, lead-acid (VRLA) cell at a charge voltage which has a value that is slightly in excess of the value of the open-circuit voltage of the cell, wherein, during charging of the cell, there is produced at the positive and negative electrodes respectively oxygen gas and hydrogen gas in a predetermined amount, and wherein the negative electrode tends to discharge over a prolonged period of time during charging, the improvement comprising inhibiting the tendency of the negative electrode to discharge during charging by controlling the amount of oxygen gas in the cell by catalytically converting a portion of the oxygen gas and a portion of the predetermined amount of hydrogen gas to water, for example, by use of a catalyst positioned in the cell.