Hydraulic arrangement for tractor-trailer brake hydraulic circuits

#This application claims benefit of and is a National Stage entry from PCT Application No. PCT/EP2019/061972, filed on May 9, 2019; which claims priority to and benefit of Italian Application No. IT 102018000005234, filed on May 10, 2018, both of which are entitled “Hydraulic Arrangement for Tractor-Trailer Brake Hydraulic Circuits”, both of which are herein incorporated by reference in their entirety.

#The present invention concerns an hydraulic arrangement, in particular an hydraulic arrangement for connecting tractor-trailer hydraulic circuits.

#Trailer may be connected to the brake hydraulic circuit of a tractor thanks to known tractor-trailer brake valve configured to allow piloting of the trailer brake pressure.

#For a better understanding of the present invention, a preferred embodiment is described in the following, by way of a non-limiting example, with reference to the attached drawings wherein:

#FIG. 1 is a scheme of an hydraulic arrangement for controlling a tractor-trailer brake valve according to the present invention;

#FIG. 2 is a section view of a first element of the hydraulic arrangement of the present invention in a first operative condition;

#In FIG. 1 it is discloses, as functional scheme, an hydraulic arrangement 100 configured to connect the braking hydraulic circuit 101 of a tractor with braking hydraulic circuit 102 of a trailer.

#Such hydraulic arrangement 100 comprises essentially a source of fluid 103 in constant pressure coming from tractor hydraulic circuit (e.g. driveline control at 20-26 bar), a coupler stage 104 fluidly connectable to trailer braking hydraulic circuit 102 and a selection pilot stage 105 fluidly connected to coupler stage 104. Preferably selection stage 105 is realized integrated in coupler stage 104.

#Hydraulic arrangement 100 further comprises a curve selection stage 106 fluidly connected to coupler stage 104, in particular to selection pilot stage 105, and to tractor brake hydraulic circuit 101 and a hydraulic trailer brake valve 107. Preferably selection stage 106 is realized integrated in trailer brake valve 107. Trailer brake valve 107, as known, is fluidly connected to a source of fluid 108 at high pressure (i.e. 150 bar about), e.g. a main pressure pump and/or a tractor tank, and to a drain of tractor hydraulic circuit.