Linear drive
DFPI-...-...-ND2P-E-P-G2
Festo AG & Co. KG
Postfach
73726 Esslingen
Germany
+49 711 347-0
www.festo.com
(en) Operating instructions
8029193
1309a
[8029195]
Original: de
Linear drive DFPI-...-...-ND2P-E-P-G2
English
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
Operating elements and connections using as an example the DFPI-100-...
2
1
4
3
9
aJ
5
6
7
8
6
6
6
aA
aB
aC
1
Mounting thread (reverse side,
Fig. 4)
2
Piston rod with mounting thread
for coupling and spanner flat for
counter holding
3
Slot for proximity sensor
4
Representation without flange
receptacle
5
Electrical connection behind the
flange receptacle
6
Thread for mounting the flange
receptacle
7
Earth terminal; position depends
on piston diameter of the drive
8
Pneumatic interface*
)
– channel 4
(extend piston rod)
9
Pneumatic interface*
)
– channel 2
(retract piston rod)
aJ
Electric cable (displacement
encoder)
aA
Optional: connecting cable with
protective conduit (accessories)
aB
Flange receptacle;
shape dependent on the piston
diameter of the drive
aC
Cylinder barrel; version depends
on the piston diameter of the drive
*
)
Pneumatic connection
Fig. 10
Fig. 1
2
Design
The DFPI-...-...-ND2P-E-P-G2 is an electro-pneumatic linear drive consisting of:
– a double-acting pneumatic cylinder with
– integrated displacement encoder (potentiometer) for determining the actual
position.
The displacement encoder supplies an analogue signal proportional to the dis-
placement in the form of a voltage (voltage divider).
If necessary, proximity switches can be installed in the slots (
Fig. 1
3
) in order
to provide binary interrogation of positions as well.
The electric and pneumatic connections are protected against external mechanical
influences by a rugged flange receptacle.
A connecting cable with protective conduit (
Fig. 1
aA
) is available as an access-
ory (
www.festo.com/catalogue).
The product is available in various designs. These operating instructions describe
the following product variants:
Features
Type
codes
Description
Type
DFPI–
Double-acting pneumatic drive for process automation with
integrated displacement encoder
Size of
valve actuator
100–
125–
160–
200–
250–
320–
Piston diameter can be selected in steps;
Specifications in [mm]
Stroke
...–
(40 ... 990)
Stroke length freely selectable in the range from 40 to 990;
specifications in [mm]
Cushioning
N
No cushioning
Displacement
encoder
D2
Integrated analogue displacement encoder
Method of
measurement
P–
Potentiometer
Attachment position
of controller
E–
External (no controller integrated)
Connection type
P–
Protected pneumatic connections
Generation
G2
2nd generation
Fig. 2
Type code (e.g. DFPI-100-200-ND2P-E-P-G2)
The following characteristics of the linear drive are dependent on the piston
diameter, and may differ from the representation shown in Fig. 1:
– Position of the earth terminal (
identification on product),
– Shape of the cylinder barrel
– Shape of the flange receptacle.
In addition, for linear drives with a piston diameter ≥ 200 mm the compressed air
supplied from one side is fed via an unprotected line parallel to the cylinder barrel.
Tie rod screws are used to attach the cylinder end cap. For linear drives with a
piston diameter ≤ 200 mm the compressed air is fed internally. The cylinder end
caps are screwed to the housing.
3
Function
Pressurising and venting of the cylinder
chambers cause the piston rod connec-
ted to the piston to move to and fro.
The integrated displacement encoder
transmits the current position to the
higher-level system as an analogue
signal.
Fig. 3
The process valve (e.g. guided slide gate, penstock valve), which is connected via a
coupling, opens or closes corresponding to the movement of the piston rod. The
cross-sectional area of the piston rod causes differences of force between forward
stroke and return stroke (
www.festo.com/catalogue).
4
Application
The designated use of the DFPI linear drive is to drive linearly actuated, guided
process valves in process automation systems – for example guided gate valve
actuators and penstock valves. It is suitable for use in the process industry in the
area of:
– water,
– sewage,
– industrial process water,
– silage and
– bulk goods technology.
The stroke length of the drive is generally at least equal to the nominal diameter of
the process valve, so that the gate valve actuator can be opened and closed com-
pletely using the DFPI.
The product is tailored to the requirements of the process industry (
catalogue
www.festo.com/catalogue).
