The hydraulic cylinder has a cylinder rod 110 in which one end is provided with a positioning mechanism 120 for adjusting the position of the cylinder rod in the axial direction.

The interiors of the hollow cylinder and hollow cylinder rod form an interior chamber (12) that is pressurized with gas to bias the cylinder rod so as to compensate for the tare weight of the material handling apparatus.

The invention provides that the sensor magnet (20) is fastened on the cylinder rod rotatably with respect to the cylinder rod (16) and is guided non-rotatably with respect to the cylinder housing (12).

A change in position of the cylinder rod (12, 112) or damage (122) to the cylinder rod (12, 112) can be detected by analyzing the number and strength of the signal pulse (126).

A roller disc is rotatably supported at one end of the cylinder rod for rolling contact between the cylinder rod and the cam surface of the cam member ring.

The cylinder rod (12, 112) is then placed proximate to a sensor assembly (14, 14A).

The actuator rod moves through and is concentric with the pressing sleeve (100).

A guide mechanism used for guiding the arm pin push rod (7) and the cylinder pin (2) to move is disposed in the cylinder head (1), and the guide mechanism is connected to a driving mechanism.

A hollow cylinder (10) projects from the blind end (6) through an opening in the piston assembly and into the hollow cylinder rod (14), the hollow cylinder (10) and the piston assembly being sealingly and slidably connected.

The invention concerns a device wherein a spring (18) is interposed between the sliding carriage (6) bearing a driving hammer (13) and the actuator rod.

One of the cylinder rod (12, 112) and the sensor assembly (14, 14A) are moved relative to the other.

An armoured cylinder rod and a protective structure for the main body of the cylinder ensure that this critical component is kept from harm even when the jaw is deep into debris.

The silver piece is the steel capping on the top of the keel head and the gold bar is the starboard ram rod.

An annular tapered piston (40), providing tightness between the two cylinder chambers, is mounted sliding on the median portion (34) of the cylinder rod between the piston (7) and the annular protuberance (33).

The hydraulic cylinder has a cylinder rod 110 in which one end is provided with a positioning mechanism 120 for adjusting the position of the cylinder rod in the axial direction.