EP1167748A2
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EP
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A self-compensating piezoelectric actuator for a control valve
Assignee: Centro Ricerche Fiat SCpA
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Filing: 2001-06-28
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Granted: —
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Expires: 2021-06-28
Abstract
Abstract An actuator device for a control valve is described and comprises a piezoelectric actuating member (12) for bringing about the movement of a closure member (30) of the valve between an open position and a closure position; the member (12) has a reference portion (20) for connection to a fixed portion (26) of the device and a free portion (24) for connection to the closure member (30), the free portion (24) being movable relative to the reference portion (20) as a result of mechanical deformations produced in the actuating member (12) by the piezoelectric effect. The reference portion (20) of the actuating member (12) is controllable selectively between a condition in which it is locked in a reference position and is fixed firmly to the fixed portion (26) of the device, and a free condition in which it is movable relative to the fixed portion (26).
Inventors
- 👤 Mario Montuschi
- 👤 Eugenio Faggioli
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 06:23
CPC Classifications
F; F02; F02M; F02M63/00; F02M63/0012; F02M63/0031; F02M51/00; F02M51/06; F02M51/0603; F02M63/0014; F02M63/0015; F02M63/0026; F02M63/0059; F02M63/0066; F16; F16K; F16K31/00; F16K31/004; F16K31/007; F02D; F02D41/00; F02D41/20; F02D41/2096; H; H10; H10N; H10N30/00; H10N30/80; H10N30/88
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
152 words
An actuator device for a control valve, comprising a
piezoelectric actuating member (12) for bringing about the
movement of a closure member (30) of the valve between an
open position and a closure position, in which the actuating
member (12) has a reference portion (20) for connection to a
fixed portion (26) of the device and a free portion (24) for
connection to the closure member (30), the free portion (24)
being movable relative to the reference portion (20) as a
result of mechanical deformations produced in the actuating
member (12) by the piezoelectric effect, the device being characterized in that the reference portion
(20) of the actuating member (12) is controllable
selectively between a condition in which it is locked in a
reference position and is fixed firmly to the fixed portion
(26) of the device, and a free condition in which it is
movable relative to the fixed portion (26).
Claim 2
Dependent Claim
69 words
An actuator device according to Claim 1, characterized in
that it comprises means (34) for bringing the actuating
member (12) to a reference position at rest which
corresponds to a rest condition of the valve and relative to
which the open and closure positions are defined, and means
(40; 50, 51, 54) for locking the reference portion (20) of
the actuating member (12) in the reference position thus
reached.
Claim 3
Dependent Claim
55 words
An actuator device according to Claim 2, characterized in
that the means for bringing the actuating member (12) to the
reference position comprise a reaction spring (34)
associated with the fixed portion (36, 26) of the device and
acting on the free portion of the member (12) when the
member (12) is not electrically excited.
Claim 4
Dependent Claim
36 words
An actuator device according to Claim 2, characterized in
that the reference portion (20) of the actuating member (12)
is hold on a support member (22) movable relative to the
fixed portion (26) of the device.
Claim 5
Dependent Claim
43 words
An actuator device according to Claim 4, characterized in
that the fixed portion (26) has a cup-shaped portion in the
cavity of which the actuating member (12) is arranged
axially, and in that the support member (22) can slide
axially in the cavity.
Claim 6
Dependent Claim
33 words
An actuator device according to Claim 5, characterized in
that the support member (22) can be locked relative to the
fixed portion (26) of the device by magnetic attraction
towards the fixed portion.
Claim 7
Dependent Claim
57 words
An actuator according to Claim 6, characterized in that the locking means comprise an electrical winding (40)
associated with the fixed portion (26) and arranged
substantially coaxially with the support member (22), the
support member (22) being capable of being attracted
magnetically radially towards the fixed portion (26) of the
device when the winding (40) is energized.
Claim 8
Dependent Claim
48 words
An actuator device according to Claim 5, characterized in
that it is arranged to direct some of the fluid controlled
by the valve into a space provided between the support
member (22) and the fixed portion (26) of the device, so as
to lubricate the portions (22, 26).
Claim 9
Dependent Claim
28 words
An actuator device according to Claim 5, characterized in
that the support member (22) can be locked relative to the
fixed portion (26) of the device by friction.
Claim 10
Dependent Claim
81 words
An actuator device according to Claim 9, characterized
in that the locking means comprise at least one pair of
opposed sliding blocks (50, 51) associated with the support
member (22) and a corresponding piezoelectric locking member
(54) arranged diametrally between the blocks (50, 51) for
moving the sliding blocks (50, 51) apart to bring them into
contact with the fixed portion (26) of the device as a
result of mechanical deformations induced in the locking
member (54) by the piezoelectric effect.
Claim 11
Dependent Claim
43 words
An actuator device according to Claim 2, characterized
in that the locking means comprise a plurality of check
members associated with the fixed portion (26) for engaging
the piezoelectric actuating member (12) as a result of an
activation control imparted by hydraulic means.
Claim 12
Dependent Claim
52 words
An actuator device according to any one of the preceding
claims, which can be controlled by means of an electronic
driver circuit (60-64), characterized in that it also
comprises an electronic control circuit (66, 68) for the
locking means (40; 50, 51, 54), integrated with the driver
circuit (60-64) of the actuator.
Claim 13
Dependent Claim
29 words
An actuator device according to Claim 12, characterized
in that the electronic control circuit (66, 68) is arranged
for periodic activation of the locking means (40; 50, 51,
54).
Claim 14
Dependent Claim
61 words
An actuator device according to Claim 12 or Claim 13, characterized in that it is arranged to direct some of the
fluid controlled by the valve towards the electronic control
circuits (66, 68) of the locking means (40; 50, 51, 54) and
the driver circuit (60-64) of the actuator, so as to enable
the circuits (60-64; 66, 68) to be cooled.
References Cited (Backward Citations)
No citation records indexed.
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