Abstract: A downhole tool mechanism for applying a driving force, such as a cutter tool for cutting a line captured within the tool, comprises a resiliently compressible member for storing a compressive force; a retaining device for maintaining storage of the compressive force until released; a trigger mechanism for releasing the compressive force when the trigger mechanism is activated. In one form the resiliently compressible member comprises a plurality of concentrically arranged spring washers each having a radial slot therein for receiving a line along the length of the resiliently compressible member. In the cutter form, there is a cutter arranged to cut the line when the trigger mechanism is activated, and the trigger mechanism is activated when the tool receives a shock force to one or both ends.

Abstract: A method for managing deposits within a pump mechanism (81) is provided. Fluid suitable for dissolving, diluting or otherwise disengaging deposits which have accumulated on the internal working surfaces of the pump is brought into contact with the mechanism. The performance of the pump is monitored and this data is used together with process data received from, or associated with, a tool (83) being evacuated by the pump to calculate (80) fluid flow characteristics which are required to compensate for the accumulation of deposits on the internal working surfaces of the pump. Fluid is then introduced (2, 84) into the pumping mechanism in accordance with the calculated characteristics.

Abstract: Embodiments of the invention relate to an apparatus for assisted walking on stairs or other sloped surfaces. The apparatus may also be used for assisted walking on slippery surfaces. The apparatus comprises a fixed support and a moveable support. The fixed support is fixed relative to the stairs or other walking surface, while the movable support is selectively moveable relative to the stairs and fixed support in a direction substantially parallel to an incline of the stairs. The movable support is selectively positionable relative to the fixed support in one of a plurality of closely spaced discrete locking positions in which the movable support can support a personal relative to the stairs.

Abstract: A downhole tool and a running tool are described, each being retrievably settable within a suitably sized cased well bore without the need for any interaction between the downhole tool or the running tool and any restrictions or recesses in the well bore to land, anchor or retrieve either tool. The downhole tool has a mandrel, an anchoring means mounted on the mandrel and controllably reconfigurable from a retracted configuration to permit movement of the downhole tool through the well bore to a radially expanded configuration for releasably engaging the cased well bore. The downhole tool anchoring means is reconfigured using a ratchet that resists movement of the tool anchoring means from the expanded configuration back to the retracted configuration until a release mechanism is released to allow retraction of the downhole tool anchoring means and retrieval of the downhole tool from the well bore.