Crane

Patent metadata

Field	Value
Publication number	US-10829350-B2
Application number	US-201716090399-A
Country	US
Kind code	B2
Filing date	Apr 7, 2017
Priority date	Apr 8, 2016
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

A crane 1 , the hook (main hook 24 ) of which is stored on the lower end of a boom 7 , and the winch (main winch 9 ) of which can be moved by a hydraulic motor 37 , said crane being provided with a pressure sensor 55 capable of detecting the pressure of hydraulic fluid being delivered to the hydraulic motor 37 , and a controller 61 capable of recognizing changes in the pressure of the hydraulic fluid on the basis of a signal from the pressure sensor 55 , and also being provided with an anomaly warning means Mi capable of providing warning of anomalies pertaining to the storage of at least the hook ( 24 ), the controller 61 activating the anomaly warning means Mi when it is determined that the pressure of the hydraulic fluid when the hook has been stored is below a minimum value.

First claim

The invention claimed is:

1. A crane, comprising:
a boom;
a wire rope that runs from a proximal end to a distal end of the boom;
a winch that is driven by a hydraulic motor, and that winds up the wire rope and releases the wire rope;
a hook that is lifted and lowered by winding up and releasing the wire rope in a state where the hook is hung by the wire rope, the hook being stored below the boom by further winding up the wire rope from a state where the hook is in contact with the boom;
a pressure sensor that detects a pressure of hydraulic fluid to be delivered to the hydraulic motor;
an abnormality notification section that issues a notification of abnormality at least pertaining to storing of the hook; and
a controller that recognizes a change in pressure of the hydraulic fluid, based on a signal from the pressure sensor, the controller actuating the abnormality notification section in a case where it is determined that the pressure of the hydraulic fluid falls below a lower limit value when the hook is stored.

2. The crane according to claim 1 , wherein the controller actuates the abnormality notification section in a case where it is determined that the pressure of the hydraulic fluid exceeds an upper limit value when the hook is stored.

3. The crane according to claim 1 , further comprising
a supply blocking section capable of blocking supply of the hydraulic fluid,
wherein the controller actuates the supply blocking section in a case where it is determined that the pressure of the hydraulic fluid exceeds an upper limit value when the hook is stored.

4. The crane according to claim 3 ,
wherein a direction switching valve is configured to switch a flow direction of the hydraulic fluid,
the crane comprises, as the supply blocking section, an operation signal pressure unload valve capable of releasing a signal pressure of the direction switching valve, and
the controller actuates the operation signal pressure unload valve in a case where it is determined that the pressure of the hydraulic fluid exceeds an upper limit value when the hook is stored.

Assignees

• Tadano Ltd

Inventors

• Fukumori Yasuhiro
• Kawabuchi Naoto
• Yoshida Naofumi

Classifications

• B66C23/705

  telescoped by hydraulic jacks · CPC title

• B66C23/36

  mounted on road or rail vehicles; Manually-movable jib-cranes for use in workshops; Floating cranes (with pneumatic or hydraulic motors B66C23/54; vehicle or ship aspects B60 - B63) · CPC title

• B66C1/36

  with means, e.g. spring-biased detents, for preventing inadvertent disengagement of loads · CPC title

• B66C2700/0357

  Cranes on road or off-road vehicles, on trailers or towed vehicles; Cranes on wheels or crane-trucks · CPC title

• B66D1/54

  Safety gear · CPC title