classification of various types of front loader arms design geometry conformation

[barracane]

classification of various types of front loader arms design geometry conformation?

Hi, sorry if I open the discussion by reading the various characteristics of the conformation of the front arms, 2 primary designs emerge, parallel arms for the tool holders and the Z system with rocker arm and connecting rod linkage for digging, such as the Hanomag dresser O & K and so on. of the Z system, many caterpilla-type companies, Komatsu and most recently Volvo, have modified them to give more visibility and less space to the operator during load lifting and bucket opening and closing maneuvers, I believe to improve the panoramic view of the work area. In your opinion, which manufacturer makes the best and most functional loader arms based on geometry and conformation? Thank you

 

[Old Operator]

Hi the Z bar linkage was originally patented by the Drott company & used on their loader conversions for IH machines. The Bristol Taurus was also an early user (probably under licence as I am told the Taurus was designed by the same man as the B100) Once the patent lapsed it was found on many others, inc the 3CX that used a low profile Z bar link. Cat took it up on the rear engined 943 in about '80

 

[barracane]

thanks for your intervention, I saw that Volvo boasts a lot about the design and geometry of its loader arms, so I took the liberty of adding to the discussion, thanks, best wishes

????

 

[Bri963]

Hi the Z bar linkage was originally patented by the Drott company & used on their loader conversions for IH machines. The Bristol Taurus was also an early user (probably under licence as I am told the Taurus was designed by the same man as the B100) Once the patent lapsed it was found on many others, inc the 3CX that used a low profile Z bar link. Cat took it up on the rear engined 943 in about '80

John Deere used it on some of their front engined machines.

 

[barracane]

Z kinematics
On the short, usually curved lifting arm, there is a central rocker arm, the reversing lever - in larger devices there are two - and a coupling rod. The lift and tilt cylinders are hinged to the machine frame.
Characteristics: The oil presses on the entire surface of the piston. This means that the maximum amount of force is effective during work. When the material is tipped, the smaller area on the side of the rod is exposed to oil, which results in a higher rod speed and therefore a faster emptying time.
Disadvantage: when docked



a pallet fork, this deviates up to 10° from the exact parallel guide. This can be resolved by manually or automatically adjusting the tilt cylinder. Compared to parallel kinematics, Z kinematics results in a somewhat stockier structure and therefore a shorter machine length.

Parallel kinematics
In this structure the tilt cylinder engages in the center of the reversal lever; The coupling rod is then parallel to the lift arm. The tilt cylinder is attached to the machine frame.
Features: The breakout and breakout force is lower than with Z kinematics because the oil pressure acts on the rod side of the




piston. However, the guidance of the work tools is more precise because the equipment maintains the low position when it is raised.
TP kinematics (= Torque Parallel Linkage from Volvo) combines Z and parallel kinematics. This results in good parallel guidance of the blade with almost constant breakout forces.

Kinematics of work tools
When lifting a full shovel, its position must not change. How is this guaranteed?
Two lever or kinematic systems are used in loaders to move the bucket or other work tools:
- the Z kinematics
- parallel kinematics.