Coupling device for work tools in telehandlers

Abstract

A coupling device for coupling work tools to a telescopic boom of a telehandler, including a tool-holder plate connectable to the telescopic boom; a coupling plate configured to be fixed to a work tool and releasably retained by the tool-holder plate; a jig including a locking seat fixed to the coupling plate and a locking cylinder, provided with a seat pad fixed to the tool-holder plate and at least one piston, the piston being selectively switchable between a locking position engaged with the locking seat, and an unlocking position which frees the locking seat; a connection device including a first connector rigidly fixed to the coupling plate and a second connector fixed to a connector-holder plate mounted on the piston and alternatively translatable between a connection position, in which each second connector connects to a first connector when the piston is in the locking position, and a disconnection position, in which the second connector disconnects from the first connector when the piston is in the unlocking position.

1 . A coupling device for coupling work tools to a telescopic boom of a telehandler, comprising:
 a tool-holder plate configured to be connected to the end of the telescopic boom;   a coupling plate configured to be fixed to a work tool and releasably retained by the tool-holder plate;   a jig comprising at least:
 a locking seat fixed to the coupling plate and 
 a locking cylinder, provided with a seat pad fixed to the tool-holder plate and at least one piston extendable with respect to the seat pad along an extension direction, wherein the piston is selectively switchable between a locking position, in which it engages the locking seat, and an unlocking position, in which it frees the locking seat; 
   a hydraulic and/or electrical connection device comprising:
 one or more hydraulic and/or electrical first connectors each rigidly fixed to the coupling plate and 
 one or more hydraulic and/or electrical second connectors each fixed to a connector-holder plate mounted on the piston and alternatively translatable between a connection position, in which each second connector mechanically connects to a respective first connector when the piston is in the locking position, and a disconnection position, in which all the second connectors mechanically disconnect from the respective first connectors, when the piston is in the unlocking position. 
   
     
     
         2 . The coupling device according to  claim 1 , wherein each first connector and each second connector has the respective connection axis parallel and eccentric with respect to the central axis of the locking cylinder. 
     
     
         3 . The coupling device according to  claim 1 , comprising centring means configured to centre each second connector with respect to the respective first connector during the translation from the disconnection position to the connection position. 
     
     
         4 . The coupling device according  claim 1 , wherein the centring means comprise one or more centring pins, mounted on the connector-holder plate or the coupling plate and adapted to axially fit in respective centring holes made in the coupling plate or the connector-holder plate. 
     
     
         5 . The coupling device according to  claim 3 , wherein the centring means are integrated with the at least a first connector and/or to the at least a second connector, which is of the self-centring type. 
     
     
         6 . The coupling device according to  claim 1 , wherein the one or more first connectors and the one or more second connectors comprise one or more hydraulic connectors for the passage of a hydraulic fluid and/or one or more electrical connectors for the passage of an electrical power line and/or electrical signals. 
     
     
         7 . The coupling device according to  claim 1 , wherein the connector-holder plate and/or each of the second connectors is movable in translation with respect to the piston from a forward position, in which the connector-holder plate and/or each of the second connectors is distal from the seat pad, to a rearward position, in which the connector-holder plate and/or each of the second connectors is proximal to the seat pad, in contrast with pushing means, wherein the connector-holder plate is mounted on a sleeve coaxially fitted on the piston and axially sliding thereon between the rearward and forward position, said pushing comprising a spring interposed between the piston and the sleeve. 
     
     
         8 . The coupling device according to  claim 1 , wherein the locking cylinder is of the double-acting type and comprises a single seat pad and two opposite pistons, on each of said pistons a respective connector plate is mounted, provided with one or more second connectors aligned, along the extension direction, with respective first connectors fixed to the coupling plate. 
     
     
         9 . The coupling device according to  claim 1 , wherein the coupling plate comprises:
 an upper semi-cylindrical seat with concavity facing downwards, wherein the semi-cylindrical seat can be engaged by a cylindrical beam connecting the tool-holder plate, and   a lower bracket facing the semi-cylindrical seat configured to define an abutment for the tool-holder plate and to prevent a slipping and/or insertion translation of the tool-holder plate on a radial plane of the semi-cylindrical seat parallel to the extension direction.   
     
     
         10 . The coupling device according to  claim 1 , wherein at least one of the tool-holder plate and the coupling plate comprises first sensor means configured to detect a correct alignment position of the locking cylinder with respect to the locking seat along the extension direction. 
     
     
         11 . The coupling device according to  claim 1 , wherein at least one of the tool-holder plate and the coupling plate comprises second sensor means configured to detect a parameter indicative of the type of work tool which is connected to the coupling plate. 
     
     
         12 . The coupling device according to  claim 1 , wherein at least one of the tool-holder plate and the coupling plate comprises third sensor means configured to detect the correct connection of one or more second connectors with one or more first connectors and/or the correct positioning of the piston in the locking position. 
     
     
         13 . The coupling device according to  claim 1 , wherein an electrical switch device for opening/closing an emergency electrical circuit is mounted on the connector-holder plate. 
     
     
         14 . The coupling device according to  claim 1 , wherein on the seat pad of the locking cylinder are provided two non-return valves in series, the non-return valves are commanded. 
     
     
         15 . A telehandler, comprising:
 a coupling device according to  claim 1 ;   a telescopic boom, one free end of which is coupled to a tool-holder plate of the coupling device;   one or more work tools each selectively couplable to the free end of the telescopic boom, wherein each work tool is provided with one said coupling plate of the coupling device.