Brackets and automatic hook


Identifying the brackets, yokes, swinging drawbars and automatic hook


Brackets
a : brackets for standard swinging drawbar
b : brackets for swinging drawbar with roller
c : brackets with short ladder with a stud for attaching the trailer eye-bolt
d : brackets with long ladder

Yokes
e : Lemoine standard yoke
f : Cramer automatic yoke

Swinging drawbars
g : standard swinging drawbars
h : swinging drawbar with roller

Hook
i : Dromone automatic hook
Tightening torques for bolts
- (1) : 480 - 640 Nm (Loctite 270, automatic hook only)
- (1) (2) (3) : 480 - 640 Nm
- (4) : 100 - 130 Nm


Adjusting the rods and automatic hook control

Adjusting the rods
On the bracket, disconnect the lower yokes of the rods and the control cable.
Start the engine. With the assistance of another operator, operate the interior or exterior lift control (depending on option) so that the lift arms are in the maximum high position (continuous pumping).


Compress the lower part of the hook along the axis of the tractor as indicated by F, using a trolley jack and to obtain a dimension X of 3.5 mm to 6.5 mm between the top of the main bracket and the top of the mobile plate.

Adjust the length of the rods by turning their square section (1) so as to engage the yokes (2) on pins (3) of the bracket.
Fit the pins. Remove the jack. Reconnect the control.

Adjusting the control


On the lever 
Place the "L" lever in the "Neutral" position. Screw yoke (1) flush with the threaded end of cable (2). Assemble the yoke on the lever using clip (3). Tighten nut (4). Adjust the sheath end (5) on bracket (6) with an equal length of thread showing on each side of the nuts (7) (8). Check that the cable is not pinched.

On the automatic hook 


Screw yoke (1) flush with the threaded end of the cable (2).
Fit the yoke on link B using clip (3) and ensure that the link is in the locked position. Tighten nut (4). Assemble the sheath end (5) in bracket (6) and tighten nuts (7) (8) so that there is no play in cable (2and the cable is not pinched. During adjustment, take care that link B remains locked.

Operating principle of the Dromone retractable hook


Construction 
- The automatic hook assembly comprises a main bracket (1) fixed to the centre housing, a mobile plate (2) that can be raised or lowered by the lift control and a retractable hook (3) operated by a double acting hydraulic cylinder (4).

Operation 

Plate lowered
- When the manual valve (1) is opened and the auxiliary lever No. 1  located on the console is operated, the high pressure passing through the unions (2) connected to quick-disconnect couplings A and B of the spool valve concerned supplies the double acting cylinder (4) integral with the retractable hook (3).


- The hook can then extend and retract to connect a trailer, depending on the position the auxiliary lever is placed in.


Plate raised

- In this configuration, the locking safety of the retractable hook is provided when it is at maximum retraction, with plate (2) previously raised and engaged.

- The principle is two mechanical locks located at the rear of the main bracket. 

When the previously stated conditions exist, the lock bolts enter their respective recesses in the retractable hook and prohibit any further movement. On placing in the safety position, the locks must produce a clack that is audible by the operator during maximum retraction of the hook.

During retraction of the hook, the operator in the driving seat should check that the gear and handbrake levers are in the neutral position. This facilitates the coupling of a trailer.

Special point 

- When valve (1) is closed, the cylinder is hydraulically isolated from the auxiliary spool valve and thus permits normal use of the spool valve.

- Periodically grease the safety lock mechanism and the mobile plate control cable.