JPS641343Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a tensioning device for a wire rope for extension in a boom extension/retraction device.

(Prior Art) In boom extension and retraction devices such as cranes, for the purpose of reducing the weight of the entire boom extension and retraction device, it is widely practiced to extend and retract the tip boom using a wire rope instead of using a cylinder device.

In this case, the wire rope must be kept under tension at all times. For this reason, conventionally, for example, a boom extension and retraction device as shown in FIG. 1
The end of the piston rod 11 of the first cylinder device 5 is pivotally attached 15 to the base end of the boom 2, and the ground portion 12b of the first cylinder device 5 is pivotally attached 16 to the base end of the first intermediate boom 2. The first intermediate boom 2 is configured to extend and retract with respect to the proximal end boom 1 by the first cylinder device 5, and the end of the piston rod 13 of the second cylinder device 6 is pivotally connected to the proximal end of the first intermediate boom 2. , the ground portion 14b of the second cylinder device 6 is pivotally attached to the base end of the second intermediate boom 3.
9, the second intermediate boom 3 is configured to expand and contract with respect to the first intermediate boom 2 by this second cylinder device 6, and the ground portion 14b of the second cylinder device 6
A reduction pulley 7 is rotatably supported on the holder, and the other end of the reduction wire rope 9, one end of which is fixed to the cylinder end 12a of the first cylinder device 5, is guided toward the proximal end to reduce the reduction. After hanging around the small pulley 7, it is guided to the tip side and fixed 30 to the tip of the tip boom 4, and the extension pulley 8 is rotatably supported on the cylinder end 14a of the second cylinder device 6. , the other end of the elongating wire rope 10, one end of which is fixed to the cylinder end portion 12a of the first cylinder device 5, is guided to the distal end side and wrapped around the elongating pulley 8, and then guided to the proximal end side and attached to the distal end boom 4. When the second cylinder device 6 is extended, the tip boom 4 is extended with respect to the second intermediate boom 3 via the extension pulley 8 and the extension wire rope 10.
In the boom telescoping device configured such that the tip boom 4 is retracted into the second intermediate boom 3 via the retraction pulley 7 and the retraction wire rope 9 due to the reduction of the Since the part is fastened 30 to the tip of the tip boom 4, the tension of the reduction wire rope 9 can be adjusted at the tip of the tip boom, so there is no problem. However, both ends of the elongating wire rope 10 are located within the boom, making it difficult to adjust the tension.

(Problem to be solved by the invention) In the invention, this stretching wire rope 1
0 tension device.

(Means for Solving the Problem) Therefore, in the present invention, the proximal boom, the first intermediate boom, the second intermediate boom, and the tip boom are slidably inserted in order, and the first intermediate boom is inserted into the proximal end of the proximal boom. 1
The end of the piston rod of the cylinder device is pivotally connected, and the ground part of the first cylinder device is pivotally connected to the base end of the first intermediate boom, so that the first intermediate boom is connected to the base boom 1 by this first cylinder device. The end of the piston rod of the second cylinder device is pivotally connected to the base end of the first intermediate boom, and the gland portion of the second cylinder device is pivotally connected to the base end of the second intermediate boom. The second intermediate boom is configured to expand and contract with respect to the first intermediate boom by the second cylinder device, and a reduction pulley is rotatably supported on the ground portion of the second cylinder device. 1. One end of the wire rope for reduction is fixed to the cylinder end of the cylinder device, and the other end of the wire rope for reduction is guided to the base end side, wrapped around this pulley for reduction, and then guided to the tip side and fixed to the tip of the tip boom. The extension pulley is rotatably supported on the cylinder end of the second cylinder device, and the other end of the extension wire rope, one end of which is fixed to the cylinder end of the first cylinder device, is attached to the tip side. After guiding it around this extension pulley, it is guided to the proximal end side and fixed to the proximal end of the distal boom,
The extension of the second cylinder device causes the tip boom to extend with respect to the second intermediate boom via the extension pulley and the extension wire rope, and the contraction of the second cylinder device causes the reduction pulley and the reduction wire rope to be extended. In the boom extension/retraction device configured such that the tip boom retracts into the second intermediate boom through the extension pulley, the extension pulley is connected to the cylinder end portion of the second cylinder device via the tension cylinder device that can be kept oil-tight at all times. The extension wire rope is always tensioned by filling the tensioning cylinder device with oil, and furthermore, the tensioning cylinder device is configured to have a distal end section so that the oil can be filled at the tip of the tip boom. An oil sealing port is provided nearby.

(Function) Therefore, when the elongating wire rope 10 becomes loose, the tension of the elongating wire rope 10 can be immediately increased by filling oil into the sealed oil chamber of the tensioning cylinder device 22.

(Example) Hereinafter, the configuration of the present invention will be described based on an example shown in the accompanying drawings.

In FIG. 1, 1 is a proximal boom, 2 is a first intermediate boom slidably inserted into the proximal boom 1, and 3 is a first intermediate boom slidably inserted into the first intermediate boom 2. 2 an intermediate boom; 4 a tip boom slidably inserted into the second intermediate boom 3; 5 a first cylinder device for extending and contracting the first intermediate boom 2 with respect to the base end boom 1; 6 a first cylinder device; A second cylinder device that extends and retracts the second intermediate boom 3 with respect to the intermediate boom 2, the end of the piston rod 11 of the first cylinder device 5 is pivotally attached 15 to the base end of the base end boom 1, and this first cylinder The gland portion 12b of the cylinder portion 12 of the device 5 is pivotally attached 16 to the base end portion of the first intermediate boom 2. Further, the second cylinder device 6 connects the end of the piston rod 13 to the first cylinder device 5.
The cylinder portion 14 is rigidly connected 18 to a connecting member 17 fixedly attached to the gland portion 12b of the cylinder portion 14, and the gland portion 14b of the cylinder portion 14 is pivotally connected 19 to the base end portion of the second intermediate boom 3.
do. In this case, the end of the piston rod 13 may be pivoted directly to the proximal end of the first intermediate boom 2. A holding member 20 is fixed to the cylinder end portion 12a of the first cylinder device 5, and the holding member 20 slidably holds the cylinder portion 14 of the second cylinder device 6 via a bearing member 21. hold That is, as the second cylinder device 6 expands and contracts, the cylinder portion 14 moves back and forth.
The cylinder end portion 12a of the first cylinder device 5 is configured to be supported over the entire length of the cylinder portion 14 via the holding member 20. It is preferable that the bearing member 21 be of an alignment type with a spherical outer periphery so as to be able to cope with eccentricity, bending, etc. of the second cylinder device 6 to some extent.

Next, the cylinder end portion 1 of the second cylinder device 6
4a, the cylinder portion 2 of the tensioning cylinder device 22 is arranged so that the piston rod 23 protrudes in the opposite direction to the piston rod 13 of the second cylinder device 6.
4 (see Figure 2). Two extension pulleys 8, 8 are placed at appropriate positions on this piston rod 23.
These two extension pulleys 8, 8 are for guiding an extension wire rope 10 that extends the tip boom 4, as will be described later. The pulleys 8, 8 are attached to the piston rod 23 of the tensioning cylinder device 22, and the oil chamber 26 on the extension side of the tensioning cylinder device 22 is filled with oil so that the two pulleys 8, 8 are always at a predetermined extended position. The stretching wire rope is always kept under tension.
It is desirable to use grease as the sealed oil. This is because grease has a high viscosity, so there is little leakage, and it can be easily filled with a grease gun or the like. Reference numeral 27 indicates a sealing port for oil such as grease, and this sealing port is located near the tip of the tip boom so that the oil can be easily sealed. Also, the piston rod 23 of the tensioning cylinder device 22
A support device 28 for supporting the cylinder portion 14 of the second cylinder device 6 and the tensioning cylinder device 22 when the second cylinder device 6 is extended is provided at the distal end of the tension cylinder device 22 . This support device 28 is configured to have projecting portions on the upper, lower, left and right sides so as to come into sliding contact with the upper, lower, left and right inner walls of the tip boom.

Next, 7 and 7 are two reduction pulleys rotatably supported on both sides of the ground portion 14b of the cylinder portion 14 of the second cylinder device 6, and 9 is a reduction pulley for reducing the tip boom 4. Using a wire rope, bend approximately the middle part of this reduction wire rope 9 and
After the rope is hooked onto the rope hooking member 29 fixed to the cylinder end portion 12a of the cylinder device 5, it is guided to the proximal end side, hung around the two reduction pulleys 7, 7, and further guided to the distal end side. Both ends of the reduction wire rope 9 are fastened 30, 30 to the tip of the tip boom 4, respectively. Note that these two fastening parts 30 have an adjustable mechanism so that the reduction wire rope 9 can be maintained in a tensioned state.

Reference numeral 10 denotes a wire rope for extending the tip boom 4, and after this extending wire rope 10 is looped and hooked onto a rope hooking member 29 provided at the cylinder end portion 12a of the first cylinder device 5, It is guided to the distal end and hung around two extension pulleys 8, 8, respectively, and further guided to the proximal end and hooked onto a rope hooking member 31 provided at the proximal end of the distal boom 4. As described above, the stretching wire rope 10 is tensioned by the tensioning cylinder device 22 described above. Note that the wire rope for extension 10 and the wire rope for contraction 9 are hung as shown in FIG.

Next, to explain the operation of this four-stage boom extension/retraction device, when the first cylinder device 5 is extended/retracted, the first
The intermediate boom 2 extends and contracts more than the base boom 1. Second
When the cylinder device 6 is expanded or contracted, the piston rod 13 side of the second cylinder device 6 is connected to the connecting member 17.
Since the cylinder part 14 side is connected to the first intermediate boom 2 and the second intermediate boom 3 through the
expands and contracts. Note that when the second cylinder device 6 is extended, the elongating wire rope 10 is pulled via the two elongating pulleys 8, 8, so that the tip boom 4 is moved from the second intermediate boom 3 to the second intermediate boom 3. It will extend at the same time as boom 3.
Conversely, when the second cylinder device 6 is retracted, the retraction wire rope 9 is pulled through the two retraction pulleys 7, 7, so that the tip boom 4 is moved inside the second intermediate boom 3. Niko's second intermediate boom 3
At the same time, it will be reduced.

The above is an explanation of the operation of this boom extension/retraction device, but if the extension wire rope 10 becomes loose,
When oil is filled into the extension side oil chamber 26 of the tensioning cylinder device 22 from the oil sealing port 27, the extension wire rope 10 is immediately stretched with the same tension on the left and right sides.

(Effect of idea) The effects of the present invention are as follows.

(1) Wire rope tensioning can be easily and quickly done by filling the tensioning cylinder device with oil.

(2) The oil filling port is located near the tip of the tip boom, making it easy to adjust the tension of the wire rope.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a partially detailed sectional view of the present invention shown in FIG. 1, and FIG. 3 is a diagram for explaining a state in which a wire rope is wound. 1... Proximal boom, 2... First intermediate boom, 3
...Second intermediate boom, 4...Tip boom, 5...
First cylinder device, 6...Second cylinder device, 7
... pulley for reduction, 8 ... pulley for extension, 9 ... wire rope for reduction, 10 ... wire rope for extension,
22... tension cylinder device, 23... piston rod, 24... cylinder, 26... sealed oil chamber,
27... Oil sealing port, 30... Stopping point.

Claims (1)

[Scope of utility model registration request] The base boom 1, the first intermediate boom 2, the second intermediate boom 3, and the tip boom 4 are inserted in this order so as to be freely slidable.
An end of a piston rod 11 of a first cylinder device 5 is pivotally attached to the base end of the base boom 1,
A first cylinder device 5 is provided at the base end of the first intermediate boom 2.
The ground portion 12b of the first cylinder device 5 is pivotally attached to the base end of the first intermediate boom 2 so that the first intermediate boom 2 can be extended or retracted relative to the base end boom 1. The end of the piston rod 13 of the second cylinder device 6 is pivotally attached to the base end of the first intermediate boom 2, and the ground portion 12b of the second cylinder device 6 is pivotally attached to the base end of the second intermediate boom 3.
a tensioning cylinder device 22 that is constantly sealed with oil, and a tension pulley 8 is connected to the second cylinder device 6 via a tensioning cylinder device 22 that is constantly sealed with oil, the tensioning ...
The tensioning device for the extension wire rope in a boom extension device is characterized in that the tensioning cylinder device 22 is attached to the cylinder end portion 14a of the boom, and the tensioning cylinder device 22 is filled with oil to constantly keep the extension wire rope 10 tensioned, and an oil filling port is provided near the tip of the tip boom 4 so that oil can be filled into the tensioning cylinder device 22 at the tip of the tip boom 4.