Self-advancing endoscope

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG.
1 shows an embodiment of a self advancing endoscope 10 according to the invention.
The endoscope 10 comprises an elongated flexible tubular member 12, preferably produced from a plastics material, having an elongated channel 14 defined by the tubular member 10.
The elongated channel 14 has a distal end wall 16.
The end wall 16 is adjacent the distal tip or head 18 of the endoscope 10.
The proximal end of the endoscope 10 includes an external gripping portion 20.
A piston means, in the form of steel piston 22, is slideably disposed in the channel 14 towards the end wall 16.
A means for reciprocating the piston 22, in the form of a reciprocating solenoid 24, is mounted adjacent the gripping portion 20.
The solenoid 24 is connected to the piston 22 by a flexible wire 26.
The wire 26 is ideally narrow and flexible to allow it to bend in concert with the flexible member 12 of the endoscope 10 and to move rapidly with minimal resistance through the channel 14.
Most preferably the wire 26 is similar in design to a piano wire with a flexible though solid wire core with an encircling tight wire casing running the length of the wire core and resembles the currently available endoscopic biopsy forceps wire.
A combined frequency generator and power source 28 is used to drive the solenoid 24 in a reciprocating fashion.
The reciprocating motion of the solenoid 24 is transmitted to the piston 22 by the wire 26 causing the piston to also reciprocate, as indicated by double ended arrow 30.
The piston 22 is positioned in the channel 14 such that it impacts the distal end wall 16 on each advancing stroke (ie.
each stroke to the left with reference to FIG.
1).
The impact of the piston 22 against the end wall 16 transfers momentum from the piston 22 to the head 18 of the endoscope 10 thereby acting to advance the endoscope 10 in the direction indicated by arrow 32.
The momentum of the piston 22 during its retracting stroke (ie.
each stroke to the right with reference to FIG