Valves and valve actuation – Electrically actuated valve – Having element dimensionally responsive to field
Patent
1996-10-15
1999-01-12
Lee, Kevin
Valves and valve actuation
Electrically actuated valve
Having element dimensionally responsive to field
251 57, 13762565, 60545, F16K 3100, F02M 5946
Patent
active
058576622
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a shutoff and stop valve, in particular for fuel injection systems.
2. Description of the Related Art
In all areas of hydraulic control and regulation technology, stop and shutoff valves that switch quickly and without delay are required. The dynamic properties of fuel injection systems could also be improved considerably and their design simplified by means of quick-acting shutoff valves.
SUMMARY OF THE INVENTION
The aim of the present invention is the provision of an electrically activatable stop device which possesses very good dynamic properties. Moreover, the stop device is to have a compact design, work in an operationally reliable manner and be capable of being used within a wide temperature range. These objects are achieved, according to the invention, by means of electrohydraulic stop devices having the following features: first housing, housing chamber, and hydraulic medium; axial length of which can be changed controllably, acts on the first piston; second bore of the first piston, housing, with the hydraulic medium, and chamber second piston duct to a housing outflow, and such a way that the second piston shuts off one of the piston ducts in the event of a length change in the actuator.
In another embodiment, the stop device has the following features: first housing, housing chamber, and hydraulic medium; axial length of which can be changed controllably, acts on the first piston; second bore of a second housing, housing chamber each filled with the hydraulic medium, and housing;
d) the housing chambers are connected to one another in such a way that an axial displacement of the first piston causes a displacement of the second piston; such a way that the second piston shuts off the housing inflow or the housing outflow in the event of a length change of the actuator.
The invention makes it possible to construct stop valves which respond to an electrical activation signal virtually without delay and which also still work reliably at high actuation frequencies f>1 kHz. Their use in a diesel injection system allows exact and reproducible metering of even the smallest fuel quantities, since the opening and closing times of the stop valve are in the range of .tau.<0.1 ms. Moreover, the short stop times guarantee a specific structure and breakaway of the fuel jet generated by the injection nozzle.
The preferred embodiments and developments of the invention provide that the first housing has a first and a second annular duct in the region of the side face of the first piston, and the first annular duct connects the first piston duct to the housing inflow and the second annular duct connects the second piston duct to the housing outflow.
In one embodiment, the first piston is arranged in the first housing in a rotationally fixed manner. A third piston duct may be connected to a second housing outflow opens into the stop chamber in such a way that said third piston duct is not shut off in the event of a displacement of the second piston. A fourth piston duct opening into the stop chamber is connected to a second housing inflow.
A second housing outflow opens into the stop chamber in such a way that said second housing outflow is not shut off in the event of displacement of the second piston. The first housing inflow is connected to a pressure-generating feed device. The housing inflow and the housing outflow are placed at different levels.
In one application, the second housing outflow is connected to an injection device. The second piston may be designed as a sealing valve. The end faces of the second piston are in each case smaller than the corresponding end faces of the first piston.
A capillary gap is present between the side faces of the first and/or of the second piston and the respective bore. A spring element is provided acting on the first piston. The first and/or second piston are installed in a sealed manner.
A piezoelectric, electrostrictive, magnetostrictive or electromagnetic actuator
REFERENCES:
patent: 4762300 (1988-08-01), Inagaki et al.
patent: 4995587 (1991-02-01), Alexius
patent: 5129489 (1992-07-01), Majima et al.
patent: 5417142 (1995-05-01), Lohmann
Kappel Andreas
Meixner Hans
Mock Randolf
Lee Kevin
Siemens Aktiengesellschaft
LandOfFree
Electrohydraulic stop device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrohydraulic stop device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrohydraulic stop device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1507221