Abstract: Apparatus and methods for providing controlled pressure-flow pulses which purge a catheter system with turbulent flow flushing. Accomplishment of such controlled pressure-flow pulses is provided by a variety of inventive devices including a special plunger rod for a conventional syringe, other interactive parts for conventional syringes, an in-line catheter attachable device which automatically generates the controlled pressure-flow pulses and also single pulse, digitally operated devices.

Abstract: An apparatus for comminuting lawn debris comprises an impeller housing defined by a pair of opposed axial end walls and a substantially voluted peripheral wall therebetween and includes inlet openings located on opposite end walls for introducing material into the housing and a discharge opening located on the peripheral wall for discharging material from the housing. The impeller is rotatably mounted on a drive shaft within the housing. The impeller includes a backing plate and a plurality of radially extending blades fixed to one face of the backing plate. The impeller blades cause air to be drawn in from an inlet opening and to be propelled axially into the housing and through the discharge opening. The comminuting blades shred material within the housing thereby reducing the size of the material. A chipper knife is attached to the face of the impeller opposite the blades for chipping material passing into the housing through one of the inlet openings.