Patent US5810255A successfully refreshed from Google Patents.
US5810255A
Expired / Lapsed
US
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Clamping device for a piesoelectric actuator of a fuel injection valve for internal combustion engines
Assignee: Robert Bosch GmbH
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Filing: 1996-08-22
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Granted: 1998-09-22
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Expires: 2016-08-22
Abstract
Abstract A fuel injection for internal combustion engines, having a valve member which is guided so that it moves axially in a valve body and uses a sealing face provided on a combustion chamber end to open and close an injection opening on the valve body. A piezoelectric actuator includes a piezoelectric stack, which changes in length with the action of a control voltage, is coupled to the combustion chamber end of the valve member to actuate the valve member. In order to prevent an interference with a precise adjustment motion of the valve member of an unwanted length change in the piezoelectric stack, a clamping device is provided which fixes the end of the piezoelectric stack remote from the valve member in its axial position during the injection phase of the fuel injection valve, and permits an axial compensation for play at the piezoelectric stack during an injection pause.
Inventors
- 👤 Katsuoki Itoh
- 👤 Rudolf Heinz
- 👤 Winfried Moser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:49
CPC Classifications
F; F02; F02M; F02M61/00; F02M61/16; F02M61/18; F02M51/00; F02M51/06; F02M51/0603; F02M61/04; F02M61/08; F02M61/161
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
218 words
A fuel injection valve for internal combustion engines, having a valve member (9) which is guided so that it moves axially in a valve body (1) and includes a sealing face (11) provided on a combustion chamber end face to open and close a valve seat for passage of a fuel to an injection opening (15) on the valve body (1) a piezoelectric actuator that includes a piezoelectric stack (23), said piezoelectric stack changes in length with application of a control voltage, said piezoelectric stack is coupled to an end of the valve member (9) to actuate the valve member, a valve spring (27) acts upon the valve member (9) in a closing direction, a clamping device (37) formed of a piezoelectric material that includes an operative means is provided on the piezoelectric actuator and fixes an end of the piezoelectric stack (23) remote from the valve member (9) in an axial position during the injection phase of the fuel injection valve, and permits an axial compensation for play at the piezoelectric stack (23) during an injection pause, and the clamping device (37) has a clamping ring (39) made of piezoelectric material, which encompasses a shaft of the piezoelectric stack (23) and whose inner diameter is reduced when said clamping ring is acted upon by an operating voltage.
Claim 2
Dependent Claim
218 words
A fuel injection valve for internal combustion engines, having a valve member (9) which is guided so that it moves axially in a valve body (1) and includes a sealing face (11) provided on a combustion chamber end face to open and close a valve seat for passage of a fuel to an injection opening (15) on the valve body (1) a piezoelectric actuator that includes a piezoelectric stack (23), said piezoelectric stack changes in length with application of a control voltage, said piezoelectric stack is coupled to an end of the valve member (9) to actuate the valve member, a valve spring (27) acts upon the valve member (9) in a closing direction, a clamping device (37) formed of a piezoelectric material that includes an operative means is provided on the piezoelectric actuator and fixes an end of the piezoelectric stack (23) remote from the valve member (9) in an axial position during the injection phase of the fuel injection valve, and permits an axial compensation for play at the piezoelectric stack (23) during an injection pause, and the clamping device (37) has a clamping ring (39) made of piezoelectric material, which encompasses a shaft of the piezoelectric stack (23) and whose inner diameter is reduced when said clamping ring is acted upon by an operating voltage.
Claim 3
Dependent Claim
90 words
The fuel injection valve according to claim 1, in which the sealing face (11) of the valve member (9) is constituted by an annular end face (45), which is oriented toward an end of the valve body (1), said annular end face is disposed on a valve member head piece (43) that protrudes from the valve body (1), and cooperates with said valve seat (13), which is disposed on the combustion chamber end face of the valve body (1) and defines a bore (7) that guides the valve member (9).
Claim 4
Dependent Claim
88 words
The fuel injection valve according to claim 1, in which the combustion chamber end face of the valve member (9) is embodied as said sealing face (11) which cooperates with a hollow, conical valve seat (13) disposed on the closed end of a bore (7) in the valve body (1), said bore contains the valve member (9); at least one injection opening (15) in the wall of the valve body (1) is connected to said valve seat, upstream in the flow direction of the fuel to be injected.
Claim 5
Dependent Claim
34 words
The fuel injection valve according to claim 3, in which the hollow, conical valve seat (13) on the valve body (1) has a seat angle α which is from about 60° to about 120°.
Claim 6
Dependent Claim
16 words
The fuel injection valve according to claim 4, in which the angle α is about 90°.
Claim 7
Dependent Claim
55 words
The fuel injection valve according to claim 3, in which the sealing face which is disposed on the valve member (9) and cooperates with the hollow, conical valve seat (13), is embodied as an annular edge (61) formed at a transition between a part of the valve member (9) shaft and a valve member tip.
Claim 8
Dependent Claim
32 words
The fuel injection valve according to claim 6, in which the angle γ of the valve member tip is embodied as greater than the angle α of the valve seat face (13).
Claim 9
Dependent Claim
15 words
The fuel injection valve according to claim 7, wherein the angle γ is about 180°.
References Cited (Backward Citations)
US4441101A
Cited
US4494727A
Cited
US4531676A
Cited
GB2128678A
Cited
US4584980A
Cited
US4575008A
Cited
US4605171A
Cited
US4783003A
Cited
GB2165308A
Cited
US4725002A
Cited
US4750706A
Cited
DE3608494A1
Cited
US5033679A
Cited
US4974780A
Cited
US5169067A
Cited
US5330100A
Cited
US5593134A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-09-21 | 2002-03-23 | 2002-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-21 | 2006-03-23 | 2006-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-21 | 2010-03-23 | 2010-09-22 | $7700.00 | Window Closed / Lapsed |