Monitoring and alarm device for construction machinery

1. A crane comprising:

a base;

a main boom coupled to the base, wherein the main boom is angled at a first boom angle;

a boom extension rotatably coupled to an end of the main boom, wherein the boom extension is angled at a second boom angle;

a first luffing cylinder coupled to the main boom to adjust the first boom angle;

a second luffing cylinder coupled to the boom extension to adjust the second boom angle;

a crane control system configured to move the main boom and the boom extension;

an unintentional boom movement detection system configured to detect unintentional movement of the main boom and/or the boom extension due to hydraulic leakage of the first and/or second luffing cylinder, wherein the unintentional boom movement detection system comprises:

a main boom angle sensor configured to measure the first boom angle;

a boom extension angle sensor configured to measure the second boom angle;

a first hydraulic leakage sensor coupled to the first luffing cylinder, the first hydraulic leakage sensor configured to measure the hydraulic pressure in the first luffing cylinder;

a second hydraulic leakage sensor coupled to the second luffing cylinder, the second hydraulic leakage sensor configured to measure the hydraulic pressure in the second luffing cylinder,

wherein the unintentional boom movement detection system monitors and determines, when the crane and crane control system are shut off and not in an operational state, a change in the first boom angle, the second boom angle, the hydraulic pressure in the first luffing cylinder, and the hydraulic pressure in the second luffing cylinder;

an alarm system operatively coupled to the unintentional boom movement detection system, wherein when the unintentional boom movement detection system determines that a change in the first boom angle, the second boom angle, the hydraulic pressure in the first luffing cylinder, and/or the hydraulic pressure in the second luffing cylinder exceeds a predefined tolerance limit that indicates a hydraulic leakage in the crane resulting in an undesired lowering of the main boom and/or the boom extension, the alarm system turns on at least a portion of the crane control system and generates a warning signal.

2. The crane of claim 1 , wherein the main boom further comprises first telescopic cylinders and the boom extension further comprises second telescopic cylinders, wherein the unintentional boom movement detection system further comprises:

a third hydraulic leakage sensor coupled to the first telescopic cylinders, the third hydraulic leakage sensor configured to measure the hydraulic pressure in the first telescopic cylinders; and

a fourth hydraulic leakage sensor coupled to the second telescopic cylinders, the fourth hydraulic leakage sensor configured to measure the hydraulic pressure in the second telescopic cylinders, wherein the unintentional boom movement detection system further monitors and determines a change in the hydraulic pressure in the first telescopic cylinders and the hydraulic pressure in the second telescopic cylinders,

wherein the alarm system generates the warning signal when the unintentional boom movement detection system determines that a change in the hydraulic pressure in the first telescopic cylinders and/or the hydraulic pressure in the second telescopic cylinders exceeds a predefined tolerance limit, the warning signal triggering at least one of an optical alarm, an acoustic alarm, and a wireless alarm signal.

3. The crane of claim 1 , further comprising a GPS system, which detects a change in the position of the main boom, the boom extension, the first luffing cylinder, and the second luffing cylinder, wherein the alarm system generates the warning message when the change in position exceeds a predefined tolerance limit.

4. The crane of claim 1 , wherein the unintentional boom movement detection system is automatically activated when the crane is shut-off.

5. The crane of claim 1 , wherein the unintentional boom movement detection system and the alarm system are connected to at least one of an autonomous unit that generates electricity, batteries, and a power supply line, to reduce power usage from a main crane battery.

6. The crane of claim 1 , wherein the unintentional boom movement detection system is connected to at least one of an overload limiter of the crane and a working range limiter of the crane, the unintentional boom movement detection system communicatively coupled to at least one of a sensor of the overload limiter for determining a load torque limitation and to a sensor of the working range limiter for determining a working range limitation, wherein an input access of the crane control system of the crane can be used for input of the predefined tolerance limits.

7. The crane of claim 1 , wherein the warning signal is transmitted to anti-collision controls of other construction machinery.

8. The crane of claim 1 , wherein the alarm system is connected to a teleservice system, which informs a central location when the predefined tolerance limit is exceeded.

9. The crane of claim 1 , wherein the unintentional boom movement detection system further comprises:

a main boom length sensor configured to measure a length of the main boom; and

a boom extension length sensor configured to measure a length of the boom extension.

10. A method of monitoring a crane with a monitoring and alarm device, the crane comprising a main boom, a boom extension, a first luffing cylinder coupled to the main boom, and a second luffing cylinder coupled to the boom extension, the method comprising:

shutting off the crane;

when the crane is shut off, monitoring parameters with the monitoring and alarm device including a first boom angle of the main boom, a second angle of the boom extension, a hydraulic pressure of the first luffing cylinder, and a hydraulic pressure of the second luffing cylinder, which parameters change during unintentional movement and an undesired lowering of the main boom or the boom extension, wherein changes of the parameters indicate a hydraulic leakage in the crane;

when the crane is shut off, issuing an alarm signal with the monitoring and alarm device when the monitored parameters change and exceed a predetermined tolerance limit; and

triggering, with the alarm signal, at least one of an optical, an acoustic, and a wireless alarm.

11. The method of claim 10 , wherein said monitoring parameters comprises monitoring a change in length of first telescopic cylinders of the main boom and second telescopic cylinders of the boom extension that can change during an undesired lowering of the at least one boom section when the crane is shut off.