Abstract: An electrosurgical instrument is provided for the treatment of tissue in the presence of an electrically-conductive fluid medium. The instrument comprises an instrument shaft (10), a tissue treatment electrode (12) at one end of the shaft, and removal means, the instrument having an apertured portion (20a) through which matter can be aspirated by the removal means from the region surrounding the tissue treatment electrode. The removal means comprises a channel formed within the instrument shaft (10) and leading from the apertured portion (20a). The channel is provided with agitation means (14) for preventing the build-up of sublimation products within the channel.

Abstract: An electrosurgical instrument is provided for the treatment of tissue in the presence of an electrically-conductive fluid medium. The instrument comprises an instrument shaft (10), and a tissue treatment electrode (12) at the distal end of the shaft for electrosurgically excising tissue pieces at an operation site. The tissue treatment electrode (12) is cyclically movable relative to the distal end of the shaft (10). Threshold control means are provided for controlling the power threshold for vaporisation of the electrically-conductive fluid medium at the tissue treatment electrode (12).

Abstract: An electrosurgical instrument is provided for the treatment of tissue in the presence of an electrically-conductive fluid medium. The instrument comprises an instrument shaft (10), and a tissue treatment electrode (12) at the distal end of the shaft for electrosurgically excising tissue pieces at an operation site. The tissue treatment electrode (12) is cyclically movable relative to the distal end of the shaft (10). Threshold control means are provided for controlling the power threshold for vaporization of the electrically-conductive fluid medium at the tissue treatment electrode (12).

Abstract: A process of forming an end closure of one end of a stick of shirred sausage casing. The casing 10 is twisted and then the twisted neck (16) is compressed and heated to seal it. The twisted portion is severed so as to form an end seal with about four to eight twists in it. This end seal resists rupture during stuffing.

Abstract: A process for impregnating a continuous sheet of glass fibre web, paper, carbon fibre, cloth etc., which comprises feeding the sheet continuously into a closed vessel filled to a suitable height with a polymer solution, immersing the sheet under the surface of polymer solution while causing solvent boiling to occur and solvent vapor bubbles to flow out of the sheet, whereby bubbles of gas, such as air held or absorbed in the sheet during the immersion, are automatically removed from the sheet and then withdrawing the sheet from the vessel.

Abstract: Apparatus for shirring a tubular casing includes a pair of shirring wheels with helical teeth.The wheels 21,22 (FIG. 9) are moulded from flexible rubber or polyurethane. The leading edge 43 of a tooth of one wheel 22 is aligned (shown by a nominal straight line 48) with the leading edge 42 on the adjacent tooth on the other wheel 21.The helical teeth are of controlled flexibility and the wheels may include circumferential walls joining the teeth.Other features of the invention relate to the curvature of the crest or face surface of the teeth which are related to wheel diameter and to the desired diameter of the shirred stick or slug which is to be produced.

Abstract: An apparatus for shirring a tubular casing in which the compression of the shirred stick is produced by employing a tapered mandrel positioned between shirring wheels. The taper is carefully chosen to produce uniform shirring and compression.In the drawing (FIG. 3) is shown part of a shirring machine comprising a pair of shirring wheels 21.22 located on opposite sides of a mandrel 15. The mandrel 15 has a tapered section 27 which begins immediately upstream of the line 27B joining the centers 21A, 22A of the shirring wheels and continues a substantial distance downstream of the line 27B. Back pressure is generated by rolls 28, 29.A preferred rate of taper is about 1 in 5 but the rate of taper may be anywhere in the range 1 in 4 to 1 in 30.