力士乐比例换向阀(4)

力士乐 比例换向阀

Function, section

Type 3DREP 6..2X/..XE...

Pilot control valve type 3DREP 6…

The pilot control valve is a 3-way pressure reducing valve that

is actuated by a proportional solenoid. It converts an electrical

input signal into a proportional pressure output signal and is

used for all valves type 4WRZ ...

The proportional solenoids are controllable wet-pin DC sole-

noids. The solenoids are actuated by external control electronics.

Set-up:

The valve basically consists of:

– Housing (1) with connection surface

– Control spool (2) with pressure measuring pins (3 and 4)

– Solenoids (5 and 6) with central thread Functional description:The pressure in A or B is set by means of the proportional so-

lenoids. The amount of the pressure depends on the current.

With de-energized solenoids (5, 6), the control spool (2) is

held in the central position by means of the compression

springs (8). Ports A and B are connected with T so that the

hydraulic fluid can flow off to the tank without obstructions.

By actuating a proportional solenoid, e.g. solenoid "b" (5), the pressure measuring pin (4) and the control spool (2) with it are moved to the left. This opens the connection from P to A and B to T via orifice-type cross-sections with progressive flow characteristics. With the surface of the pressure measur-ing pin (3) the pressure that builds up in channel A acts on the control spool and against the solenoid force. The pres-sure measuring pin (3) is supported by the solenoid "a". If the pressure exceeds the value set at solenoid "b", the control spool (2) is pushed back against the solenoid force and con-nects A with T until the set pressure is achieved again. The pressure is proportional to the solenoid current.When the solenoid is switched off, the control spool (2) is re-turned to the central position by the compression springs (8).

Important:

If valves version 3DREP 6 C are used, only one solenoid may

be actuated at a time.Valve with two spool positions

(type 3DREP 6…A…)

The function of this valve version basically corresponds to the

valve with three spool positions. This 2 spool position valve

is, however, only equipped with solenoid "b" (5). Instead of

the 2nd proportional solenoid, there is a plug screw (7).Important:The tank line must not be allowed to run empty. With cor-responding installation conditions, a preload valve (preload pressure approx. 2 bar) must be installed.