Abstract: The present disclosure discloses an acousto-magnetic (AM) anti-theft marker and use thereof. The AM anti-theft marker includes at least one resonator(s), where when the resonator(s) does not include cobalt, a weight percentage of nickel is 0 wt % to 39 wt %; or when the resonator(s) includes cobalt, a total weight percentage of nickel and cobalt is higher than 0 wt % and no more than 36 wt %. Although this AM anti-theft marker's resonator(s) of the present disclosure does not include or only includes a very small amount of nickel and cobalt, it still has good alarm performance; and the existing detectors can effectively detect the AM anti-theft marker of the present disclosure within a predetermined security alarming distance. It can be seen that this AM anti-theft marker has a commercial value, and can reduce the loss prevention cost of business and the consumption of earth resources.

Abstract: The present invention relates to a telescopic device of single-cylinder latch type and a crane. The telescopic device of single-cylinder latch type is applied to a telescopic boom system and includes: a telescopic cylinder, for driving telescopic boom sections of the telescopic boom system to execute a telescopic action relative to a basic boom section; double boom pin structures, arranged on both sides of the tails of the telescopic boom sections to lock and unlock the telescopic boom sections; an boom pin pulling and plugging mechanism, arranged on the cylinder barrel of the telescopic cylinder to execute pulling and plugging operations on the double boom pin structures; and a cylinder pin structure and a cylinder pin cylinder, both arranged on the cylinder barrel of the telescopic cylinder and to lock and unlock the cylinder barrel of the telescopic cylinder and the telescopic boom sections.

Abstract: The present invention relates to a telescopic device of single-cylinder latch type and a crane. The telescopic device of single-cylinder latch type is applied to a telescopic boom system and includes: a telescopic cylinder, for driving telescopic boom sections of the telescopic boom system to execute a telescopic action relative to a basic boom section; double boom pin structures, arranged on both sides of the tails of the telescopic boom sections to lock and unlock the telescopic boom sections; an boom pin pulling and plugging mechanism, arranged on the cylinder barrel of the telescopic cylinder to execute pulling and plugging operations on the double boom pin structures; and a cylinder pin structure and a cylinder pin cylinder, both arranged on the cylinder barrel of the telescopic cylinder and to lock and unlock the cylinder barrel of the telescopic cylinder and the telescopic boom sections.