摘要:
A face sealing annular valve (1) for a fluid-working machine has an annular valve member (10, 50, 60, 70, 80, 90, 100, 110) having a relaxed configuration in which a first seat-engaging surface (14, 101) of the annular valve member can sealedly engage with a first sealing surface of an annular valve seat (8), but a second seat-engaging surface (15, 101) cannot sealedly engage with a second sealing surface (9), and is elastically deformable to a deformed configuration in which the second seat-engaging surface can sealedly engage with a second sealing surface, while the first seat-engaging surface remains sealedly engaged with the first sealing surface. The annular valve member can be made with relatively high tolerances and is only loosely retained by a guide in the relaxed configuration.
摘要:
A hydraulic pump comprises (1) an outward ring (24), including demountable blocks (30) comprising piston cylinders (32), and an inward ring (21), comprising a ring cam (23), coupled through a drive shaft (8) to the blades of a turbine (4). To enable maintenance, the outward ring is decoupled from a torque limiting device (16, 17) and rotated relative to the inward ring. Demountable blocks are then removed from the outward ring using a crane (61) including a line (62) extending from above the centre of mass of the demountable block and including a resilient portion (66) so that although the crane supplies the majority of the force required to remove the demountable block, an operator provides some force, enabling the process to be controlled. The method is suitable for maintaining large hydraulic pumps in wind turbine nacelles (2).
摘要:
A wind turbine generator, or other energy extraction device, has a hydraulic circuit comprising a hydraulic pump driven by a rotating shaft and a hydraulic motor driving an electricity generator. When the electricity generator is switched off, it executes one or more pumping cycles to pressurise the high pressure manifold and therefore recover angular kinetic energy from the electricity generator rotor which can later be used to reaccelerate the electricity generator rotor to the correct operating speed for an electricity grid. Overall energy efficiency is increased and the minimum operating high pressure manifold pressure may be reduced as a result.
摘要:
Sailcloth of longitudinal direction (machine direction) including a carrier layer, an intermediate layer with several plies of laid yarn as well as a finishing layer, with the yarns being bonded under pretension with the carrier layer and the layers joined with each other, the intermediate layer includes at least three yarn layers the yarns of which being laid at an angle ranging between 55 and 125° relative to the longitudinal direction so that at angles of 60° to 120° and 240° to 300° in relation to the longitudinal direction the cloth has a stretching resistance at 1% of expansion of at least 150 Ibf (667 N).
摘要:
A fluid-working machine has working chambers (4), each of which is connected to a fluid commutating means (2) which alternately connects the working chamber to either of two fluid manifolds (A, B). An electronically controlled valve (1) is inserted into the flow path between each chamber (4) and the commutating means. This valve is commanded by a controller (6) receiving an input signal of the phase angle of the shaft (5) of the machine or at least one electronic pulse per revolution which informs the controller that the shaft is passing a known phase angle. The valve (1) allows overriding of fixed mechanical commutation by closing the valve cyclically, synchronised with the angular position of the shaft (5). Thus the controller (6) is able to vary the time-averaged fluid flow into or out of the machine by varying the proportion of chambers (4) which are isolated from or connected to the mechanical commutating means (2), to control the torque, speed, and/or fluid flow into and out of the machine.
摘要:
A fluid-working machine has a plurality of working chambers, e.g. cylinders (11), of cyclically changing volume, a high-pressure fluid manifold (14) and a low-pressure fluid manifold (16), at least one valve (13, 15) linking each working chamber to each manifold, and electronic sequencing means (20) for operating said valves in timed relationship with the changing volume of each chamber (11), wherein the electronic sequencing means is arranged to operate the valves of each chamber in one of an idling mode, a partial mode in which only part of the usable volume of the chamber is used, and a full mode in which all of the usable volume of the chamber (11) is used, and the electronic sequencing means (20) is arranged to select the mode of each chamber on successive cycles so as to infinitely vary the time averaged effective flow rate of fluid through the machine.
摘要:
A fluid working machine has at least one working chamber of cyclically varying volume and low and high pressure valves to regulate the flow of working fluid into and out of the working chamber, from low and high pressure manifolds. The low and high pressure valves are actuated by electronically controlled valve actuation means which, when actuated, applies forces to the low and high pressure valve members to open and/or close the respective valves. The low and high pressure valve members are independently moveable and, although the low pressure valve member typically begins to move quickly in response to a shared valve control signal, the high pressure valve member typically moves only after a change in the pressure within the working chamber. The electronically controlled valve actuation means may be a shared electronically controlled valve actuator, such as a solenoid within a magnetic circuit which directs magnetic flux through both low pressure and high pressure valve armatures which are connected to the respective valve members.
摘要:
A fluid working machine has at least one working chamber of cyclically varying volume and low and high pressure valves to regulate the flow of working fluid into and out of the working chamber, from low and high pressure manifolds. The low and high pressure valves are actuated by electronically controlled valve actuation means which, when actuated, applies forces to the low and high pressure valve members to open and/or close the respective valves. The low and high pressure valve members are independently moveable and, although the low pressure valve member typically begins to move quickly in response to a shared valve control signal, the high pressure valve member typically moves only after a change in the pressure within the working chamber. The electronically controlled valve actuation means may be a shared electronically controlled valve actuator, such as a solenoid within a magnetic circuit which directs magnetic flux through both low pressure and high pressure valve armatures which are connected to the respective valve members.
摘要:
An annular valve (1) has an annular valve member (4) and inner and outer annular valve seats (12, 14). Inner and outer sealing ridges (8, 10) are formed either on the annular valve member or on the valve seats. The inner sealing ridges are more resistant to plastic deformation than the outer sealing ridges. They may be thicker, or made from a harder material. Thus, the annular valve better resists damage arising from greater plastic deformation of the inner sealing ridge than the outer sealing ridge due to greater forces (Fi, Fo) acting on the inner sealing ridge than the outer sealing ridge in use.
摘要:
An object of the present invention is to provide a hydraulic pump structure which improves the ease of mounting the hydraulic pump on the main shaft, and a method of mounting the hydraulic pump which can be performed in a simplified manner. A hydraulic pump unit 10 is formed by unitizing a cylindrical member 46 fit into an outer circumference of the main shaft 12 and a hydraulic pump body 76 arranged on an outer circumferential side of the cylindrical member 46. The hydraulic pump body 76 comprises a ring cam 52 mounted on the outer circumference of the cylindrical member 46, a pump bearing 54, a pump housing 34, a plurality of piston 58 housed in the pump housing 34 and actuated by the ring cam, and a plurality of cylinders 60 which guide the plurality of pistons in a radial direction and are arranged in a circumferential direction, and the hydraulic pump unit 10 is configured such that the pump unit 10 is insertably fixed to the main shaft 12 by the cylindrical member 46.