Danfoss 45 Frame K2 Series, Руководство по обслуживанию, Страница: 6 / 40

Symbols used in Danfoss literature
WARNING may result in injury Tip, helpful suggestion
CAUTION may result in damage to product or
property
Lubricate with hydraulic fluid
Reusable part Apply grease / petroleum jelly
Non-reusable part, use a new part Apply locking compound
Non-removable item Inspect for wear or damage
Option - either part may exist Clean area or part
Superseded - parts are not interchangeable Be careful not to scratch or damage
Measurement required Note correct orientation
Flatness specification Mark orientation for reinstallation
Parallelism specification Torque specification
External hex head Press in - press fit
Internal hex head Pull out with tool – press fit
Torx head Cover splines with installation sleeve
O-ring boss port Pressure measurement/gauge location or
specification
The symbols above appear in the illustrations and text of this manual. They are intended to communicate
helpful information at the point where it is most useful to the reader. In most instances, the appearance
of the symbol itself denotes its meaning. The legend above defines each symbol and explains its purpose.
General description
Danfoss Series 45 K2 frame open circuit piston pumps convert input torque into hydraulic power.
Rotational force is transmitted through the input shaft to the cylinder block. The input shaft is supported
by tapered roller bearings at the front and rear of the pump and is splined into the cylinder block . A lip-
seal at the front end of the pump prevents leakage where the shaft exits the pump housing. The spinning
cylinder block contains nine reciprocating pistons. Each piston has a brass slipper connected at one end
by a ball joint. The slippers are held to the swashplate by the spring retainer and block spring. The block
spring also holds the cylinder block to the valve plate. The reciprocating movement of the pistons occurs
as the slippers slide against the inclined swashplate during rotation. Via the valve plate, one half of the
cylinder block is connected to pump inlet and the other half to pump outlet. As each piston cycles in and
out of its bore, fluid is drawn from the inlet and displaced to the outlet thereby imparting power into the
system circuit. A small amount of fluid is allowed to leak from the cylinder block / valve plate and slipper /
swashplate interfaces for lubrication and cooling. Case drain ports are provided to return this fluid to the
reservoir.
The volume of fluid displaced into the system circuit is controlled by the angle of the swashplate. The
swashplate is forced into an inclined position (into stroke) by the bias spring. The servo piston opposes
the action of the bias spring forcing the swashplate out of stroke when hydraulic pressure in the control
circuit rises above the spring force.
The pump control, by varying the pressure at the servo piston, controls the displacement of fluid in the
system circuit. Controls designed for Pressure Compensation (PC) or Load Sensing (LS) are available. For a
detailed description of control operation, refer to
Control options, operation .
Service Manual
Series 45 Frame K2 Open Circuit Axial Piston Pumps
Introduction
6 | © Danfoss | April 2017 AX00000301en-US0101