TSE PTV100/72, Руководство пользователя

Страница: 274 / 480

saue
13
Series 90 Functional Description 2
PV with Manual Displacement Control and Neutral
Start Switch
PV with Hydraulic Displacement Control
PV with Manual Displacement Control
90000237
90000239
90000240
2.5 Pump Control Options
2.5.1 Manual Displacement Control (MDC)
The manual displacement control converts a mechani-
cal input signal to a hydraulic signal using a spring-
centered four-way servo valve. This valve ports
hydraulic pressure to either side of a dual-acting
servo piston. The servo piston rotates the cradle
swashplate through an angular rotation of
±
17
°
, thus
varying the pump’s displacement from full displace-
ment in one direction to full displacement in the
opposite direction. The MDC is designed so the
angular position of the pump swashplate is propor-
tional to the rotation of the control input shaft. For
adjustments see
8.2.1 ; for repairs see 9.3.2 , 9.3.8 .
Non-Linear MDC
The non-linear manual displacement control (photo
in
Sec. 8.2.2 ) operates in the same manner as the
regular MDC except that it is designed so the change
in the angular position of the pump swashplate
pro-
gressively increases as the control input shaft is
rotated toward its maximum displacement position.
For adjustments see
Sec. 8.2.2 ; for repairs see 9.3.2 .
Solenoid Override Valve
A solenoid override valve option (not shown here) is
available for MDC. This safety feature will return the
swashplate to zero displacement position when acti-
vated. The valve may be set in either a normally open
or normally closed mode. For repairs see
9.3.3 , 9.3.4 .
Neutral Start Switch (NSS)
The neutral start switch is an optional feature avail-
able with MDC. When connected properly with the
vehicle’s electrical system, the neutral start switch
ensures that the prime mover can be started only
when the control is in a neutral position. For adjust-
ments see
Sec. 8.2.3 .
2.5.2 Hydraulic Displacement Control
(HDC)
The hydraulic displacement control uses a hydraulic
input signal to operate a spring-centered four-way
servo valve. This valve ports hydraulic pressure to
either side of a dual-acting servo piston. The servo
piston rotates the cradle swashplate through an
angular rotation of
±
17
°
, thus varying the pump’s
displacement from full displacement in one direction
to full displacement in the opposite direction. The
HDC is designed so the angular position of the pump
swashplate is proportional to input pressure. For
adjustments see
8.2.4 ; for repairs see 9.3.5 , 9.3.8 .
CONTENTS