Page 37 - Clippard - Electronic Valves

NEW! EFB ELECTRONIC FILL & BLEED CIRCUITS

Manifold Only In-Line Mount #8-32 x 0.244 deep
mtg. holes
typ. (2) places
Material: Black anodized
aluminum 0.438
0.188 0.156
Part No. Description 0.500
EFB-1M* In-Line Manifold Only 0.875
EFB-2M** Manifold Mount Manifold Only “A”
#10-32 x 0.170
deep ports 0.750
* Specify your own manifold mount DV, DT or EM valve when 0.438 typ. (3) places sq.
selecting the manifold only.
Manifold Mount
0.500
** Specify your own manifold mount DV, DT, EV or EM valve when 0.219
selecting the manifold only. 0.656 0.250
1.000
See Pages 177 through 203 1.250 0.201 dia. drill thru
0.375 dia. x 0.190
deep c'bore
0.250 2.000 mtg. holes typ.
Circuit “A” “B” 2.500 (2) places
EFB-1DV 4.874
EFB-1EM 3.057
EFB-2EV 2.310
“B”
EFB-2DV 2.812
0.750
0.375
0.375 1/8 NPT
0.688 ports typ. 0.438
1.719 (3) places

Three Typical Examples of Fill and Bleed Applications

Pressure control systems typically use a fill In lumbar Position is based on the same princi-
and bleed type circuit to add or subtract air support ple when applying a fill and bleed cir-
in maintaining pressure. They can also be re- applica- cuit along with the basic cylinder
ferred to as E/P or Electronic Pressure Control tions, formula of PRESSURE X AREA =
when feedback is provided to read the pressure FORCE and linear spring force. Using
downstream or output pressure and looped would be a single acting cylinder, the linear
back to tell a PLC or System to fill or bleed better de- spring force on the cylinder needs to
more pressure. These can be tremendously fined as be overcome with a particular pres-
accurate depending on the speed and orifice firmness, sure in order to move. As the cylinder
of the valves used in the circuit and the ac- where a moves, the force required to push
curacy of a pressure transducer. pneumatic fill and bleed circuit is con- against the spring force changes,
trolling the air pressure in a flexible therefore varying the pressure can
bladder built into a seat. Massage or simply vary the position. For exam-
therapy chairs use multiple bladders fill- ple, if a cylinder was used to move
Clippard EV ing and bleeding pressure that changes the position of a table up or down, a
valves are com- the firmness in a sequential pattern mas- fill and bleed circuit can be applied
monly used in saging the user. These applications can to the bottom of the cylinder to adjust
these applica- be found in first-class airline seats, train pressure, which in turn changes the
tions in analyti- seats, truck or mobile cabs where the position.
cal and instrumentation operator is sitting for extended periods
equipment, medical devices such as blood of time.
pressure cuffs, and pressure control industrial
applications.
The components can be quite simple and robust, such as the FBV manual fill and bleed valves. Or, for integration with elec-
tronic controls, a combination of electronics valves can achieve very simple or more complex circuit for your fill and bleed
applications.

211 Clippard Instrument Laboratory, Inc. 877-245-6247 www.clippard.com