US Patent 7992636 Device and method for retrieving debris from a well

A device for use in retrieving debris from a well, including an elongate body; a main bore extending part way along a length of the body; an opening towards a lower end of the body; a main fluid chamber in the body in fluid communication with the main bore; a flow restriction provided in the main bore, through which fluid flows from the main bore and into the main fluid chamber; at least one chamber outlet for directing fluid from the main fluid chamber into an annulus defined between the device and a well borehole wall; a return flow passage extending between the body opening and the main fluid chamber, for return flow of fluid from the annulus to the main fluid chamber, to facilitate retrieval of debris from the well; and at least one fluid exit, for flow of fluid out of the device.