JPH0367956B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for extending and retracting a jib from a boom in a wheel crane such as a truck crane or a rough terrain crane.

[Conventional technology]

In general, the storage method for the compression column type jib attached to the telescopic boom in wheeled cranes is the under-carrying type, in which the jib is stored on the underside of the boom.
There is a side-held type in which the jib is stored on the side of the boom in a horizontal position with the jib thickness facing up and down.

In both of these storage methods, in the case of the undercarriage type, the thickness of the boom and jib in the vertical direction becomes large, so the visibility during traveling, especially the side visibility, becomes narrow. In addition, if you try to improve visibility, the overall height of the crane vehicle will increase, which also poses a problem when traveling.

On the other hand, in the case of the side-carrying type, although the side visibility is widened, the thickness in the left-right direction is also large, which poses a problem in that it becomes difficult to turn on narrow running roads.

Furthermore, regarding the work of extending and retracting the jib, in the horizontal holding method, the jib is rotated approximately 180 degrees from the side to the front on a horizontal plane, so a large space must be secured on the side.

In addition, in the lower hugging method, the jib is moved almost from the bottom to the top.
It was extremely troublesome to pass the main hook between the jib feet when rotating it 180 degrees and extending it.

Therefore, the present invention stores the jib horizontally on either the left or right side of the boom in a vertical position with its thickness direction facing left or right, and from this stored position, the jib can be easily extended even in narrow spaces. This provides a retractable jib extension and a method for storing it.

[Means to solve the problem]

In the present invention, the jib is stored on the side of the boom in a vertical position with the jib's thickness direction facing left and right, and the connecting parts on both sides of the base end of the jib are located vertically. (ii) In this jib hanging state, the jib is connected to either the left or right side of the boom tip and the jib is hung down using this connection point as a fulcrum. a jib twisting process in which the jib is twisted around the longitudinal axis until it is located on the other side; (iii) a jib lifting process in which the jib is pulled up using the connection point as a fulcrum after this jib twisting; and (iv) this jib lifting process. Afterwards, the jib is extended through a process of passing a tension member between the jib and the tip of the boom, and the jib is retracted through the process reverse to the process of extending the jib, and at the time of tensioning the jib, the above In order to make the jib twisting angle approximately 90 degrees during the jib twisting process, before the jib hanging process, move the jib from the stowed position to the drooping preparation position on the side of the boom, and move it in the opposite direction when stowing the jib. It is something.

The present invention also provides a method for extending and storing a jib for a crane as set forth in claim 1, in which the jib is connected to a connection point between a connecting portion located at the lower side in the stored state and either the right or left side of the tip of the boom. The jib is moved between the storage position and the drooping preparation position by rotating the jib around the axis in the length direction of the jib using the jib as a fulcrum.

[Effect]

This allows the jib to be stored vertically on the side of the boom, ensuring side visibility during travel and maneuverability in narrow spaces, while also making it easy to extend and store the jib even in narrow spaces.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 show the jib in an extended state, and FIGS. 3 and 4 show the jib in a retracted state.

1 is a telescopic boom, 2 is a compression column type jib, and 3 is a suspension rod as a tension member.

In addition, here, in order to make the explanation easier to understand, the telescopic boom 1 will be replaced with the base end boom 1A, which is a fixed boom.
and a tip boom 1B which is a movable boom.
Although a case of a stage telescopic boom is illustrated, the present invention is of course applicable to a two stage telescopic boom or a three stage telescopic boom. In addition, the left and right hereinafter refer to the left and right as seen from the driver's seat.

As is well known, the jib 2 includes a number of connecting rods 2c between a pair of side rods 2a, 2b made of flat square pipes, etc.
... are fixed together to form a flat frame with a tapered end.

Jib mounting shafts 4 and 5 are attached to the left and right sides of the tip of the boom 1, that is, the tip of the tip boom 1B (boom point), so that they can rotate around their axis x, and when the jib is extended, the base end of the jib 2 The connecting parts 6 and 7 provided on both the left and right sides are connected to the jib mounting shafts 4 and 5.
I am trying to connect it to.

Note that both jib attachment shafts 4 and 5 may be formed by using a single through pin, or by attaching separate pins on both sides to the tip of the boom.

The connecting portions 6 and 7 on both the left and right sides are both formed in a bifurcated shape. Of these, the left connecting portion 6 is formed into a fork shape in which the length of the two pieces forming the bifurcation is equal, and the right connecting portion 7 is formed into a stepped fork shape in which the length of one piece is shorter than the other piece. are doing.

These connecting portions 6 and 7 are formed separately from the jib body, that is, the side rods 2a and 2b, respectively, and the right side connecting portion 7 is fixed to the base end of the right side rod 2b.

On the other hand, the left connecting portion 6 integrally has a male threaded portion 6a as shown in FIG.
It is screwed into a socket 6b fixed to the inside of the base end of the left side rod 2a of the jib.

In this way, the left connecting portion 6 is attached to the base end of the left side rod 2a of the jib so that it can be screwed around the same side rod axis (the connecting portion axis) y.

In addition, the right connecting part 7 has a pin hole 9 at one location, and the left connecting part 6 has two pin holes 8a and 8b at the tip and middle part, of which the pin hole 8b in the middle part is shaped like a long hole. is forming. Furthermore, pin holes 4a and 5a are provided in the jib mounting shafts 4 and 5 on both the left and right sides in the radial direction.

As shown in Figures 3 and 4, the jib 2 is stored on the left side of the base end boom 1A in a vertical position with its thickness direction facing left and right. It is fixed (stored and held) to the base end boom 1A at two places.

First, to explain the jib tip side fixing mechanism, as shown in Figs. 1 to 4, as well as Figs. While protruding, the proximal boom 1
A box-shaped bracket 12 with openings on both sides in the axial direction of the boom is protruded from the left side of the base end of A, and the engagement pin 1
1 can be engaged with this bracket 12 from the front.

This bracket 12 and engagement pin 11 include
Pin holes 12 that match vertically when the jib is stored
a, 11a are provided, and the engagement pin 11 can be fixed to the bracket 12 by inserting a tip fixing pin 13 into the pin holes 12a, 11a.

In addition, as shown in FIG. 9, etc., the base end of the jib is fixed by connecting brackets 14 and 15 with pin holes protruding from the sides of the base boom 1A and the jib connecting rod 2c with the base end fixing pin 16. This is done by combining them.

On the other hand, an overhanging wire guide drum 17 is attached to the upper surface of the intermediate portion of the base end boom 1A.

Since this guide drum 17 is used only when extending and retracting the jib 2, it may be detachably attached so that it can be removed from the boom 1A when not needed. Also, this guide drum 1
A sieve may be used instead of 7.

18, 18 is the suspension rod mounting seat,
The rods 2a, 2b on both the left and right sides at the tip of the jib 2 are provided to protrude upward, and one end of the suspension rods 3, 3 is fixed to the mounting seats 18, 18 with pins 19, 19 when the jib is used or stored. I try to attach it.

Also, when storing the jib, the suspension rod 3,
3 in the jib 2, L-shaped rod holders 20, 20 are installed on the left and right sides of the base end of the jib 2, and rod holders 21, 21 are installed on the left and right sides of the middle part of the jib 2.
are provided for each.

These rod holders 22, 22 are each
As shown in FIGS. 9 and 10, there is a U-shaped holder main body 22, an opening/closing link 23 that opens and closes the upper opening of the main body 22, and a torsion coil spring 24 that always biases the link 23 in the direction of closing the main body. When the rod is stored, the main body 22 is closed by an opening/closing link 23 to hold the rod 3, and when the rod is used, the link 23 is opened so that the rod 3 can be removed from the main body 22. 22a is a pin that holds the opening/closing link 23 in an open state. Further, reference numerals 25 and 25 indicate jib twist handles provided on both left and right sides of the tip of the jib 2.

Next, the jib extension and storage method will be explained.

The jib 2 is placed along the left side of the proximal boom 1A in a vertical position in which the right side rod 2b is up and the left side rod 2a is down in the extended state, as shown in FIGS. In this state, the above-mentioned engagement pin 11 at the tip of the jib is engaged with the bracket 12 at the proximal end of the proximal boom 1A and fixed with the tip fixing pin 13, and the brackets 14 and 15 are fixed at the proximal end. By fixing with fixing pins 16, the jib 2 is held in a vertical storage position.

The jib 2 is extended from this state by the following procedure.

(b) With the crane outrigger (not shown) extended to stabilize the aircraft, fully retract the boom 1 and point it toward the side or rear of the aircraft in an almost horizontal position.

(b) As shown in Fig. 11, the overhanging wire 26 is pulled out along the base boom 1A from a manual or electric winch (not shown) mounted on the crane body, passed through the guide drum 17, and then passed through the guide drum 17 to the tip. Attach it to the middle part of jib 2.

(C) Also, as shown in the figure, remove the jib tip fixing pin 13 from the engagement pin 11 and bracket 12, and insert the same pin 13 into the pin hole 4a of the left jib mounting shaft 4 and the pin hole 8b of the left side connecting portion 6. Insert it all the way. This connects the left connecting part 6 and the jib mounting shaft 4, and the jib tip fixing pin 13
can be used as a connecting pin.

(d) Attach the jib base end fixing pin 16 to the bracket 14,
15 and release the fixation of the base end of the jib 2. This pin 16 will later be used as a connecting pin for the right side connecting portion 7.

(e) As shown by the imaginary lines in FIGS. 11 and 12, while loosening the tension wire 26, rotate the jib 2 by its own weight approximately 180 degrees around the axis y of the left connecting portion 6.

In this way, the jib 2 is moved to the drooping preparation position where the jib 2 is in a vertical position with the vertical relationship reversed from when it is stored.

(f) Raise the boom 1 to about 80 degrees and extend the boom 1 while loosening the overhanging wire 26 until the engagement pin 11 at the tip of the jib comes off the bracket 12, as shown by the imaginary line in FIG.

(G) When the jib 2 is released from the boom 1 in this way, the overhanging wire 26 is loosened to allow the jib 2 to hang down in a vertical position, as shown in FIG.

(H) Next, lower boom 1 and move the jib tip (lower end)
Lower the handles 25, 25 to a height where they can be operated from the ground. Note that the extending wire 26 may be removed from the jib 2 at this stage if possible, but it is normally removed after the jib is extended.

(Li) Holding the handles 25, 25, twist the jib 2 approximately 90 degrees around the axis y of the left side connection part as shown in Fig. 14, and then attach the right side connection part 7 to the right side jib mounting shaft 5
to engage.

In this way, since the jib 2 is twisted and set at the boom tip, the main hook (not shown) suspended from the bottom of the boom tip sheave block 29 can be easily moved around the base end of the jib 2. can. Alternatively, if you lower the main hook to the ground beforehand, you only need to change the suspension wire of the hook, so you can pass the main hook through the base end of the jib when extending the jib, as in the case of the conventional under-carrying type. You will no longer have to struggle with your work.

(J) Fix the tip of the auxiliary winding wire 27 passed through the auxiliary sheave 28 of the tip boom 1B to the tip of the jib 2, and while winding the auxiliary winding wire 27, turn the boom 1
further defeat. Alternatively, the boom 1 is further lowered while extending the tip boom 1B.

(Le) In this way, after lowering the boom 1 horizontally or slightly below it and simultaneously pulling up the jib 2, attach the previously removed jib base end fixing pin 16 to the
As shown in Figure 5, the pin insertion hole 9 of the right side connecting part 7
By inserting the connecting portion 7 into the jib mounting shaft 5, the connecting portion 7 is prevented from detaching from the jib mounting shaft 5.

In addition, once the jib tip fixing pin 13 inserted into the pin holes 8b and 4a of the left side connecting part 6 and the left side jib mounting shaft 4 in (c) above is removed, the pin 13 is inserted into the connecting part 6 as shown in FIG. into the tip pin hole 8a.

In addition, when replacing this pin 13,
Since the intermediate pin hole 8b of the left connecting portion 6 is made into a long hole, the pin 13 can be easily removed. In this way, in the jib extended state, the left side connecting portion 6 and the left side jib mounting shaft 4 are brought into close contact.

(w) Remove the base ends and intermediate parts of the suspension rods 3, 3 from the rod receivers 20, 20 and rod holders 21, 21, and as shown in FIG. Attach to. This allows suspension rods 3 and 3 to be connected to jib 2 and tip boom 1.
The jib 2 is supported by being suspended between the jib 2 and the jib 2.

(W) Pass the auxiliary winding wire 27 through the sheave block 30 of the jib 2, and attach the auxiliary hook 31 to its tip.

Through the above steps, the extension of the jib 2 is completed.

Furthermore, the jib 2 is stored in the reverse order to the above-mentioned extension procedure. To summarize the main points, the boom 1 is tilted horizontally or slightly lower, and the length is slightly extended (for example, 60 to 70 cm) rather than fully retracted.

Next, remove the auxiliary winding wire 27 from the auxiliary hook 31 and attach its tip to the tip of the jib, then remove the suspension rods 3, 3 and attach it to the jib 2 while supporting the jib 2 with the wire 27. Store.

Then, the jib tip end fixing pin 13 used as a connecting pin for the left side connecting portion 6 is reinserted in the opposite direction from when it was extended, and the jib base end fixing pin 16 is removed from the right side connecting portion 7.

After this, while raising the boom 1, raise the auxiliary winding wire 2.
7 (or by extending the tip boom 1B by about 2 m in advance and then reducing the tip boom 1B), the jib 2 is rotated downward to hang in a vertical position, and the auxiliary winding wire 27 is After removing, move the jib 2 approximately around the axis y of the connecting part.
Twist it 90 degrees.

Next, wrap the overhanging wire 26 into the jib 2.
After drawing the jib toward the boom 1 side, the boom 1 is fully retracted to engage the engagement pin 11 at the tip of the jib with the bracket 12.

After that, the boom 1 is laid down horizontally, the overhanging wire 26 is wound up, and the jib 2 is moved to the 11th,
Figure 12 Position of imaginary line (hanging preparation position when extending)
From there, twist approximately 180° to the retracted position shown by the solid line.

In this state, both the tip and base end fixing pins 1
3 and 16, the jib 2 is fixed in the retracted state.

In addition, in the above embodiment, the left side connecting portion 6 of the jib 2
Although it is configured to rotate around the axis y by screw rotation, a bearing type rotation structure may be adopted instead of the screw rotation structure.

Further, in the above embodiment, the right connecting portion 7 is formed into a bifurcated shape with different steps, but as shown in FIG. It's okay. With this shape, when the jib 2 is hung in a vertical position and twisted, the jib 2 is tilted so that the right connecting part 7 is located below the right jib mounting shaft 5 due to the jib's center of gravity. By hooking the connecting portion 7 to the right side jib mounting shaft 8, the two can be temporarily connected.

Further, according to the basic embodiment in which the right side connecting portion 7 is formed into a bifurcated shape with different steps, the jib mounting shaft 5 of the connecting portion 7 is
Although the engagement operation for the right side connecting portion 7 is easier,
Even when the left connecting portion 6 is formed into a bifurcated shape with two pieces of equal length, the intended purpose of the present invention can be sufficiently achieved.

〔Effect of the invention〕

As described above, according to the present invention, the jib is stored vertically on the side of the boom, and when it is extended, the jib is moved from the stored position to the drooping preparation position; the drooping is vertically suspended from this drooping preparation position; The process involves twisting the boom approximately 90 degrees while the jib is in the retracted state, and after this twisting, the process of pulling it up and extending it, and then retracting it in the reverse order. This makes it possible to minimize the horizontal thickness of the boom and jib when the jib is retracted. While the side-carrying type ensures good side visibility when driving, it also allows for good entry into narrow spaces.

Moreover, although it is a side-hugging storage system, there is no need to secure a wide jib turning space on the side like in the past, and the jib can be easily extended and stored even in a narrow space.

[Brief explanation of drawings]

Fig. 1 is a side view of the jib in an extended state showing an embodiment of the present invention, Fig. 2 is a plan view of the same, Fig. 3 is a side view of the jib in the retracted state, Fig. 4 is a plan view of the same, and Fig. 5 is a side view of the jib in the retracted state. FIG. 6 is an enlarged perspective view of the proximal end portion, FIG. 6 is an enlarged view of part A in FIG. 4, FIG. 7 is a sectional view taken along the line of FIG. Fig. 4 is an enlarged view of part E, Fig. 10 is a sectional view taken along the line of Fig. 9,
Figure 1 is a schematic side view showing the jib in a state in which it is ready to be extended, Figure 12 is an enlarged cross-sectional view taken along the line XII-XII in Figure 11, and Figure 13 is a schematic side view with the jib twisted approximately 180 degrees and hanging in a vertical position. Figures 14 and 14 are schematic side views with the jib further twisted approximately 90 degrees, Figures 15 and 16 are enlarged side views showing the left and right joints set in the jib extension position, and Figure 1.
Figure 7 is a schematic side view showing the fully extended state;
The figure is a side view showing a modified example of the right side connecting portion. 1... Telescopic boom, 2... Jib, 3... Suspension rod (tension member), 4, 5...
Jib mounting shafts on both left and right sides of the boom tip, 6, 7...
Connecting portions on both sides of the base end of the jib, x...Axis of the jib mounting shaft, y...Axis of the connecting portion (axis in the jib axial direction).

Claims (1)

[Scope of Claims] 1. The jib is stored on the side of the boom in a vertical position with the jib's thickness direction facing left and right, and the connecting parts on both sides of the jib's base end are located vertically, (i) the jib is placed on one side; (ii) In this jib hanging state, the jib is connected to either the left or right side of the boom tip, and the jib is hung down using this connection point as a fulcrum. a jib twisting step of twisting the jib around the longitudinal axis until it is located on the other side of the tip; (iii) a jib pulling step of pulling up the jib using the connection point as a fulcrum after this jib twisting; After the jib lifting process, the jib is extended through a process of passing a tension member between the jib and the tip of the boom, and the jib is retracted through a process reverse to the process of extending the jib, and when the jib is extended, Before the jib hanging process, move the jib from the stowed position to the drooping preparation position on the side of the boom so that the jib twisting angle in the jib twisting process is approximately 90 degrees, and move the jib in the opposite direction when stowing the jib. A method for extending and storing a jib of a wheeled crane. 2. In the method for extending and storing a jib for a crane as set forth in claim 1, the jib is extended and stored using the connection point between the connecting part located below in the stored state and either the right or left side of the boom tip as a fulcrum. A method for extending and storing a jib for a wheeled crane, characterized in that the jib is moved between a storage position and a drooping preparation position by rotating the jib around its longitudinal axis.