Abstract: A ballistic device is easily and safely operated and modified by students to change different variables between experiments performed by the students. For example, the ballistic device is configured to facilitate adjusting the number and/or strength of the tensioning members applying a bias to the launching member to facilitate adjusting a location of the launch pad along a length of the launching member. A trigger arrangement is configured to be actuated at a safe distance from the ballistic device.

Abstract: A weight bar system includes a weight bar, and two lock collars on each end of the weight bar for holding one or more weights on each end of the weight bar. The ends of the weight bar include circumferentially positioned grooves. A locking collar is engageable with the grooves both in an unlocked and a locked position. The locking collar includes a main body collar including pins which extend in a cross direction relative to the axis and are moveable radially inwardly and outwardly relative to the grooves. A rotatable collar includes a cam surface to move the pins radially inwardly to lock the locking collar to the weight bar. A stationary collar may also be provided to limit rotation of the rotatable collar, and to provide a gripping surface. A space on the lock collar may be provided to press against the weights.

Abstract: A weight bar system includes a weight bar, and two lock collars on each end of the weight bar for holding one or more weights on each end of the weight bar. The ends of the weight bar include circumferentially positioned grooves. A locking collar is engageable with the grooves both in an unlocked and a locked position. The locking collar includes a main body collar including pins which extend in a cross direction relative to the axis and are moveable radially inwardly and outwardly relative to the grooves. A rotatable collar includes a cam surface to move the pins radially inwardly to lock the locking collar to the weight bar. A stationary collar may also be provided to limit rotation of the rotatable collar, and to provide a gripping surface. A space on the lock collar may be provided to press against the weights.

Abstract: Stationary exercise apparatus has a frame, a chain with a seat and back adjustably mounted on the frame and a boom extending forward from the frame. A crank shaft is journaled in a gear mount at a distal end of the boom, and cranks and pedals are connected to the crank shaft. An outer telescopic member of the boom is fixed to the frame, and an inner telescopic member slides within the outer member and is clamped to the outer member. A drive shaft extending through the inner member is coupled to a flywheel and an energy absorber with an electrical feedback controller to vary the resistance as speed varies. The chair is mounted on a trunnion on side rails mounted on upright members. The fixed portion of the boom and the forward end of the rails is supported on an upright member which is welded to the leg of an "I" shaped base.

Abstract: A device comprising a combined clipboard and flexible storage pouch with closure means. The clipboard has a conventional flexible clip in its face and has the pouch secured to the rear side thereof for storage and carrying of various articles. The pouch is secured peripherally to the rear of the clipboard and a coplanar member secured to the rear of the clipboard.

Abstract: A portable desk for the convenience of invalids, traveling men or others who do not have access to other desk surfaces. The lower portion of the desk is a pillow-like portion of flexible material which forms a yieldable container which is partially filled with a dry, flowable material, such as expanded styrofoam beads, particles or the like. The casing portion is secured at the top to a piece of sub-covering of suitable size, which in turn is secured to a hard, planar sheet of material by adhesive, glue or other suitable means. The styrofoam beads may be shifted or shuffled about until the pillow-like portion adjusts to the contour of the surface on which it is to be used. An upstanding abutment secured along one side of the desk top forms a stop for books, pencils and the like to rest against.