JPH0313157B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a jib extending device for extending a jib to the tip of a telescopic boom in various types of cranes such as truck cranes and rough terrain cranes.

(Prior art) Cranes that use a jib include so-called tower cranes, in which the boom is fixed in an upright position and only the jib is swung (raised and lowered) to perform crane work.
They are broadly classified into so-called luffing cranes, which perform crane work by swinging both the boom and jib.

In such cranes, the jib usually
It is stored on the front (bottom) or side of the boom, and is extended from the tip of the boom when in use. Conventionally, the methods for extending this jib are as follows: () With the crane boom laid down on the ground, the jib is placed on the boom tip side, the jib foot is connected to the boom tip with a pin, and then the boom and jib are erected together. () Connect the jib foot to the tip of the boom via a hinge mechanism, and if the jib is side-held, turn the jib 180° from the side to the front around the vertical axis to set it in the extended position, and then raise the boom. In the case of a jib-down type, the jib is pulled up and rotated from bottom to top around a horizontal axis with the boom upright.

However, with these conventional methods, in any case, a large flat space is required for extending the jib in addition to the space occupied by the crane. In places where there is enough space above but limited space below, it has become impossible to extend the jib.

(Object of the Invention) Therefore, the present invention provides a method and device for extending a jib for a crane, which eliminates the need for extra plane space for extending the jib and allows the jib to be easily and efficiently extended within the space occupied by the crane. We aim to provide the following.

(Structure of the Invention) The invention described in claim 1 extends a jib stored on the back of a telescoping boom to the tip of the boom by at least one extension and contraction operation of the telescoping boom. A jib extending device for a crane, comprising an upper coupling means for coupling the tip of the tip end of the boom of the telescopic boom with the jib and transmitting an extension force of the telescopic boom to the jib as a jib pulling force, and a boom by the upper coupling means. a lower coupling means for coupling the jib to the tip of a boom lower than the tip boom and holding the jib in a raised position when the jib is uncoupled; a driving means for driving, a jib foot pin hole provided near the base end of the jib, and a distal end portion of the tip boom of the telescopic boom so as to be able to engage with the jib foot pin hole when the jib is extended to hold the jib in the extended position; The jib foot pin is provided with a jib foot pin, and a jib foot pin driving means for driving the jib foot pin under remote control.

Further, in the above configuration, the invention as set forth in claim 2 is provided with a first pin hole for pulling up the jib in at least one location in the tip end of the jib in the left-right direction of the jib, and a tip end of the tip boom in the telescopic boom. The upper coupling means is constructed by providing an upper pin that can be engaged with and detached from the first pin hole, and a second pin hole for holding the jib is provided at least at one location at the base end of the jib in the left-right direction of the jib. and a lower pin that can be engaged with and detached from the second pin hole is provided at the tip of the boom lower than the tip boom of the telescopic boom to constitute the lower coupling means, and the upper pin is in the jib extended state. It is constructed so that it also serves as a jib foot pin that engages with the jib foot pin hole.

(Example) This example will be explained using a rough terrain crane as an example of the crane type, but the present invention is applicable to a truck crane or a crawler whose boom is box-shaped and telescoping, regardless of this crane type. The present invention is applicable to various types of cranes, such as cranes, which are equipped with telescopic booms. Furthermore, the present invention can be applied to both the tower crane and luffing crane described above.

In the figure, 1 is the rough terrain crane body,
2 is a telescopic boom, and 3 is a jib. In the basic embodiment shown in FIGS. 1 to 6, the boom 2 has the following configurations:
This shows the case of a three-stage boom consisting of a basic boom 2a, an intermediate boom 2b, and a tip boom 2c. In addition, the jib 3 is configured to be telescopic with a built-in telescopic cylinder, and is stored in the back (upper surface) of the boom 2 in the contracted state as shown in FIG. 1A, and is extended as necessary during crane work. 11 is the outrigger of the crane body 1, S is the jib strut,
W ₁ is a wire rope for hoisting the jib, and W ₂ is a wire rope for hoisting the jib foot.

The jib 3 has first pin holes 31 and jib foot pin holes 3 along the left and right sides of the jib at three locations: the tip, the vicinity of the base, and the base.
2. A second pin hole 33 is provided. Note that the tip of the jib in the present invention refers to the tip of the jib in its stored length state. Therefore, in the case of this embodiment in which the jib 3 is telescopic, this refers to the tip of the jib in the contracted state shown in FIG. On the other hand, in the boom 2, an upper pin 4 which also serves as a jib foot pin is attached to both left and right side surfaces of the point sheave block 21 of the tip boom 2c.
is installed in a horizontal position along the left and right direction of the boom. Further, a pin bracket 22 is provided on both left and right sides of the tip end of the basic boom 2a to protrude toward the rear side of the boom, and a lower pin 5 is provided on the bracket 22 in a horizontal position along the left and right direction of the boom.

These upper and lower pins 4, 5 are connected to the third,
As shown in FIG. 4, the strokes are driven by hydraulic cylinders 6 and 7 that are remotely controlled from the driver's cab, and the expansion and contraction of the cylinders 6 and 7 causes the first pin hole 31 of the jib 3 to open in the case of the upper pin 4. Alternatively, it engages and disengages with the jib foot pin hole 32, or in the case of the lower pin 5 with the second pin hole 33, respectively. In this way, the boom 2 and the jib 3 are coupled by the engagement between the upper pin 4 or the lower pin 5 and the pin holes 31, 32, or 33.

The jib extension procedure will be explained next.

In the jib retracted state shown in FIG. 1A, the upper pin 4 engages with the first pin hole 31 of the jib 3, and the lower pin 5 is in an inoperative state. From this state, as shown in FIG. 1B, the outriggers 11 are extended, the aircraft is stabilized, and preparations for extension are made. At this time, in order to avoid interference between the base end of the jib and the rear end of the crane body when the boom is next raised, the intermediate boom 2b of the boom 2 is extended by a predetermined stroke to advance the jib 3.

Next, after raising the boom 2 as shown in FIG.
Fully extend both b and 2c to the stroke end. With this boom fully extended, jib 3 moves to boom 2.
is pulled up along the

In this boom fully extended state, the lower pin 5 and the second pin hole 33 of the jib 3 are aligned. In other words, the positions of both the upper and lower pin holes 31 and 33 are set so that such a state is obtained.

Thereafter, by engaging the lower pin 5 with the second pin hole 33 and holding the jib 3 in the raised position shown in FIG. Both booms 2b, 2
Fully contract c.

In this manner, as shown in FIG. 1E, the boom point sheave block 21 is moved toward the base end of the jib to align the upper pin 4 and the jib foot pin hole 32.

Next, insert the upper pin 4 into the jib foot pin hole 32.
By engaging the lower pin 5 and disengaging it from the second pin hole 33, the jib extension work is basically completed, and thereafter, as shown in FIG. Crane work can be carried out at both angles and jib angles.

By the way, in order to prevent unexpected movement of the jib 3 from the boom fully extended state shown in Fig. 1D to the boom fully retracted state shown in Fig. 1H, the boom point sheave block is set as shown in Fig. 5. A jib support 23 made of a square pipe etc. is installed in the rear end of the 21.
is attached along the left and right direction of the boom, and the boom 2 is fully retracted while holding the jib 3 by the left and right side walls of the sheave block 21 and the jib support 23.

On the other hand, the jib 3 is stored in the completely opposite procedure to the above-mentioned extension procedure, that is, the jib 3 is raised from the tilted state shown in Fig. 2 at the same angle as the boom 2, and then
After engaging the lower pin 5 with the second pin hole 33 and removing the upper pin 4 from the jib foot pin hole 32, the boom 2 is fully extended to the state shown in FIG. is activated and the boom is fully retracted with the lower pin 5 deactivated to return to the state C and then to the state B.

Note that when the boom 2 is fully retracted and the base end of the jib is introduced into the pin bracket 22 in order to return the jib 3 from the crane working position in the boom extended state shown by the solid line in FIG. 2 to the state shown in FIG. In order to draw the base end of the jib toward the rear side of the boom and ensure that the lower pin 5 and the second pin hole 33 are aligned, a guide structure as shown in FIG. 6 is provided. That is,
Wedge-shaped guide protrusions 34 with pointed upper and lower ends are provided on both left and right sides of the base end of the jib along the length of the jib, while a guide plate 24 is fixed to the inner surface of the pin bracket 22 of the boom 2. ing. The guide plate 24 is formed in the shape of a cam plate whose surface facing the rear surface of the basic boom 2a is inclined, and a guide groove 25 expanding upward is formed between the plate 24 and the rear surface of the basic boom. This guide groove 25 guides the guide protrusion 34 on the jib side so as to follow the rear surface of the boom, draws the base end of the jib toward the rear surface of the boom, and aligns the lower pin 5 and the second pin hole 33. I have to.

By the way, the present invention can be implemented with various modifications other than the above embodiments.

() In the above embodiment, when extending the jib, the boom 2 is pre-extended by a predetermined stroke from the state shown in FIG. However, if the storage layout is such that there is no risk of such interference, there is no need for the boom preliminary extension, and the boom 2 may be directly erected.

() In the above embodiment, the case where the raised boom 2 is extended and contracted once to complete the jib extension is explained, but the boom length is short compared to the jib length (the boom extension stroke is If the first pin hole is small), as shown in FIG.
Jib middle part second pin hole 33a as the second pin hole
The second pin hole 33b at the base end of the jib may be provided at two locations, and the jib 3 may be extended by a measuring movement in which the boom 2 is extended and contracted twice. Alternatively, the first and second pin holes may be provided at three or more locations each, so that the measuring motion may be performed many times.

() Although the above embodiment has been described using a three-stage boom as an example, the present invention is also applicable to a boom with four or more stages. In the case of a boom with four or more stages, the lower pin 5 is not necessarily provided on the basic boom, but can also be provided on an intermediate boom. In short, this lower pin 5 may be provided in the middle part of the entire telescopic boom.

() In the invention recited in claim 1, upper coupling means for coupling the boom and jib to raise the jib, and lower coupling means for holding the jib in this raised position,
Various modifications other than the pin described above are possible. Specifically, for example, first, a hydraulic jack is provided in place of the pins 4 and 5 at the pin installation position of the boom 2 shown in the above embodiment, and the boom 2 and the jib are connected by the jib clamping force of the hydraulic jack. 3. Second, a holder is provided on the boom side to be opened and closed by a hydraulic cylinder,
It is possible to adopt a means for holding the jib 3 with the holder and connecting the boom 2 and the jib 3. Further, if a means other than the pin type is employed as the upper coupling means, the jib foot pin may be provided separately.

() In the device of the present invention, the alignment between the pin and the pin hole does not necessarily have to be done by fully extending or retracting the boom as in the above embodiment, but can be done by displaying the boom length using a boom length meter. It is also possible to do so based on Alternatively, a sensor such as a proximity switch may be provided on both the pin side and the pin hole side, and positioning may be performed based on a signal from the sensor.

() In the invention set forth in claim 2, the pin driving means for remotely controlling the pin may include, in addition to the above-mentioned hydraulic cylinder,
Air cylinders, hydraulic or electric motors, etc.
This is subject to various changes.

(Effects of the Invention) As described above, according to the present invention, since the jib is pulled up and extended along the boom using the telescopic movement of the erected boom, no extra plane space is required for extending the jib. This is no longer necessary, and jib extension work can be performed within the space occupied by the crane. Therefore, the jib can be extended easily and efficiently even in places where the space below is restricted, such as inside a building under construction or in a place where electric wires are run around in an urban area. be.

[Brief explanation of drawings]

The figures show an embodiment of the present invention; FIG. 1A to E are schematic side views showing the procedure from storing the jib to extending it; FIG. 2 is a schematic side view showing the crane working state with the jib extended; Figure 3 is the − of Figure 1 D.
line, Figure 4 is an enlarged sectional view along the same line, Figure 5 is an enlarged sectional view along the line.
The figure is a vertical sectional side view of the boom tip in the state shown in Figure 1 (d).
FIG. 6 is a sectional view taken along the line of FIG. 4, and FIGS. 7A to 7E are schematic side views of a boom and a jib showing a jib extension procedure according to another embodiment of the present invention. 2...Boom, 3...Jib, 31, 31a, 3
1b...first pin hole constituting upper coupling means, 4
...Same upper pin (also serves as jib foot pin), 33,
33a, 33b...the second constituting the lower coupling means
Pin hole, 5... Lower pin, 6, 7... Hydraulic cylinder as driving means, 32... Jib foot pin hole.

Claims (1)

[Scope of Claims] 1. A jib extending device for a crane that extends a jib stored on the back side of a telescopic boom to the tip of the boom by at least one extension and contraction operation of the telescopic boom, which comprises: an upper coupling means for coupling the tip end of the tip boom of the telescopic boom with the jib and transmitting the extension force of the telescopic boom to the jib as a jib pulling force; a lower coupling means for coupling the tip of the boom below the tip boom and the jib to hold the jib in a raised position; a driving means for driving both the upper and lower coupling means under remote control; and a proximal end of the jib. A jib foot pin hole provided in the vicinity, a jib foot pin provided at the tip of the tip boom of the telescopic boom so as to be able to engage with this jib foot pin hole and hold the jib in the extended position when the jib is extended, and a remote control. A jib extension device for a crane, comprising: jib foot pin driving means for driving a jib foot pin of a lever. 2. In the jib extending device for a crane as set forth in claim 1, a first pin hole for lifting the jib is provided in at least one location at the tip of the jib in the left-right direction of the jib, and a first pin hole is provided in the left and right direction of the jib at the tip of the tip boom of the telescopic boom. The upper coupling means is constituted by providing an upper pin that can be engaged with and detached from the first pin hole, and a second pin hole for holding the jib is provided at least at one location at the base end of the jib in the left and right direction of the jib. At the same time, a lower pin that can be engaged with and detached from the second pin hole is provided at the tip of the boom lower than the tip boom of the telescopic boom to constitute a lower coupling means,
A jib extension device for a crane, wherein the upper pin is configured to also serve as a jib foot pin that engages with a jib foot pin hole when the jib is extended.