JPS63148694U - - Google Patents

Description

[Brief explanation of the drawing]

Fig. 1 shows the first embodiment of the boom extension/retraction device of the present invention, in which all the booms are in the fully retracted state, Fig. 2 is the fully extended state, and Fig. 3 is the fully extended state. Application example of the first embodiment, Fig. 4 is the second embodiment of the present invention.
An example is shown in which the fully retracted state with all booms retracted, Fig. 5 is a fully extended state diagram, Fig. 6 is an application example of the second embodiment, and Fig. 7 is a diagram of the second embodiment. This is another application example. DESCRIPTION OF SYMBOLS 1... Base end boom, 2... First intermediate boom, 3... Second intermediate boom, 4... Third intermediate boom, 5... Tip boom, 6... First cylinder device, 7... Second cylinder device, 8... First Pulley, 9...Second pulley, 10...Third
Pulley, 11... Fourth pulley, 12... Wire rope for reduction, 13... Wire rope for first extension, 14... Second
Extension wire rope, 29...bracket, 33...
Rod.

Claims (1)

[Scope of utility model registration request] The base end boom 1, the first intermediate boom 2, the second intermediate boom 3, the third intermediate boom 4, and the tip boom 5 are slidably inserted in order, and the end of the piston rod 6b of the first cylinder device 6 is inserted into the base end boom 1. The cylinder 6 of this first cylinder device 6 is attached to the first intermediate boom 2.
The ends of piston rod 6b of a are pivotally connected 15 and 16, respectively, so that the first intermediate boom 2 can be extended and contracted with respect to the proximal boom 1 by means of this first cylinder device 6, and this first cylinder A first pulley 8 is provided at the end of the cylinder 6a of the device 6, the end of the piston rod 7b of the second cylinder device 7 is connected to the first intermediate boom 2, and the cylinder 7a of the second cylinder device 7 is connected to the second intermediate boom 3. The ends on the piston rod 7b side are respectively connected to pivot connections 18.
, 19, the second intermediate boom 3 is configured to extend and retract with respect to the first intermediate boom 2 by this second cylinder device 7, and a second
A reduction wire rope 12 is provided with a pulley 9 and has one end fixed 20 to a bracket 29 provided at the base end of the second intermediate boom 3 or at the end of the cylinder 7a of the second cylinder device 7 on the piston rod 7b side. The end is guided to the boom tip side and wrapped around the first pulley 8, then guided to the boom base end and wrapped around the second pulley 9, and then guided again to the boom tip side and fixed to the tip of the tip boom 5. 21, and a first extension wire rope 13 having one end fixed 23 to the tip of the first intermediate boom 2.
Guide the other end to the boom tip side and connect it to the second intermediate boom 3.
After hanging around the third pulley 10 provided at the tip of the boom, it is guided to the boom base end side and fixed 24 to the base end of the third intermediate boom 4, and one end is fixed 25 to the tip of the second intermediate boom 3. The other end of the second elongating wire rope 14 is led to the boom tip side and wrapped around the fourth pulley 11 provided at the tip of the third intermediate boom 4, and then guided to the boom base end side and connected to the base end of the tip boom 5. A boom extension/retraction device fixed to the section 26.