JPS5844155Y2 - Counterweight attachment/detachment device - Google Patents

Description

[Detailed description of the invention] When a large truck crane is traveling on the road, it is sometimes necessary to remove the counterweight of the swivel base attached to the rear body of the truck to reduce the axle load, and this invention can be used for this purpose. This invention relates to a counterweight attachment/detachment device.

This invention is a truck crane in which a counterweight that can be lifted in an almost upright state by a lifting cable is detachably fixed on a support at the rear end of a swivel base. The arm, which has a pulley attached to its tip, can be tilted up and down between a counterweight lifting position where it is tilted rearward and upward, and a position where the counterweight is lowered and supported on the swivel base so that it is suspended and supported backwards from the holder. A separable coupling mechanism is mounted between the arm and the swivel base, and is pivoted on the swivel base to restrain the arm in the counterweight lifting position, and the top of the counterweight lifted by the lifting cable is connected to the swivel base. A stopper that engages regardless of whether the arm is tilted or raised is attached to the tip of the arm, so that a downward rotational force is constantly applied to the arm due to the tension of the lifting cable before and after the pulley at the tip of the arm and the arm's own weight. A cable guide member that guides the lifting cable on the power unit side from a pulley at the tip is mounted on the swivel base so that the counterweight engaged with the stopper does not interfere with the receiver when the arm is raised or raised. This is a characteristic feature.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

Reference numeral 1 denotes a swivel base 1 rotatably mounted on the rear body of an automobile (not shown), and the swivel base 1 supports a telescopic boom 2, which is extendable and retractable by a power unit, in a cantilever manner so as to be adjustable in elevation.

Reference numeral 3 denotes receivers fixed to both sides of the rear end of the swivel base 1. The upper edge portions of recesses 5 provided on the front surface of the counterweight 4 are engaged with the receivers 3, and the counterweight 4 is It is detachably fixed to both supports 3 by bolts 6.

Reference numeral 7 indicates a truncated conical projection fixed on each support 3 concentrically with the bolt 6, and the projection 7 has a hole 8 drilled on the counterweight side.
The counterweight 4 is loosely fitted into the holder 3 to facilitate positioning of the counterweight 4 with respect to the receiver 3, and to ensure the required screw hole length for the bolt 6.

Reference numeral 9 denotes a front gate type arm, and the lower ends of the leg portions on both sides of the arm 90 are pivoted on the swivel base 1 by pins 10 having the same axis, and on the upper end beam portion of the arm 9, there is a Pulleys 11, 12 are mounted symmetrically about the centerline.

Reference numeral 13 denotes a gate-shaped support that is fixed upright at the rear end of the swivel base 1 so as to sandwich the arm 9 therebetween.The upper end beam portion of the gate-shaped support 13 has a pulley 14 corresponding to the pulley 11 and a semicircular groove corresponding to the pulley 12. A wheel-shaped cable guide board 15 is attached.

The cable guide board 15 is preferably fixed to the portal support 13.

Reference numeral 16 denotes a counterweight lifting cable whose one end is removably fixed 19 to the tip of a boom tube 18 that is extendable and retractable with respect to the boom tube 17 at the base of the telescopic boom 20 in a horizontal position. A pulley 20 mounted on 1,
Pulleys 14, 11, and a pulley 2 installed symmetrically in the upper recess of the counterweight 4 with respect to the center of gravity of the counterweight.
1゜22, pulley 12, cable guide board 15 to turn platform 1
It is fastened 23 to the rear end wall of.

The pulleys 21 and 22 are attached to the lifting rope 1 on the counterweight 4.
6 is removably attached, and the lifting cable 16 has a length necessary to suspend the counterweight to the ground as described later.

The separable connection mechanism connects brackets 24 protruding and fixed to both sides of the upper end of the gate-shaped arm 9, and corresponding brackets 25 fixed to the upper ends of the gate-shaped support 13, respectively, by a removable pin 26. Moreover, it has a loose pin connection structure in which the pin hole 27 of the bracket 24 is formed into a long hole as shown by the chain line in FIG.

Reference numeral 28 denotes an L-shaped stopper with a horizontal fork-shaped portion 29 at the lower end, and the upper end of the stopper 28 is pivoted 31 in a symmetrical arrangement to a bracket 30 which is symmetrically fixed to the tip of the arm 9. , the counterweight lifting cables 16 hanging from the multiple pulleys 11 and 12, respectively, pass through the grooves of the fork-shaped portions 29 of the corresponding stoppers.

Reference numeral 32 denotes an engaging portion with which the lower ends of the stoppers 28 on both sides abut, respectively, and the engaging portion 32 protrudes and is fixed onto a mounting member 33 for the pulleys 21 and 210 mounted on the counterweight 4.

The present invention has the above configuration, and when the counterweight 4 is removed from the state fixed to the swivel base 1 as shown by the solid line in FIG.
The tip of the boom tube 18 is fixed 19 to the tip of the boom tube 18 in a horizontal position, and the boom tube 18 is extended from the base boom tube 17 until the cable 16 is slightly tensioned. Then, the bolt 6 is removed, and then the boom tube is further tightened. Each time the cylinder 18 is extended, the counterweight 4 is lifted vertically via the rope 16 to a position A where the engaging portion 32 thereof slightly lifts the stopper 28, and acts on the coupling mechanism (24, 25, 26). Reduce the load and connect pin 2
Extract 6.

Next, the boom cylinder 18 is contracted and the arm 9 is rotated downward around the pin 10 by gravity acting on the counterweight, and while the counterweight is moved in an arc so as not to interfere with the support 3, the arm 9 is rotated. The dashed line in FIG. 1 is supported by the swivel base 1 as shown in FIG. 2.

While this arm is rotating 90 times, the pulley at its tip is 11°12
A downward rotational moment acts on the arm due to the resultant force of the front and rear cable tensions and the weight of the arm 9, and this downward rotational moment rotates about the pivot shaft 31 along with the cable 16 below the pulley. It is received by the counterweight 4 via the stopper 28.

After the arm 9 is supported by the swivel base 1, the downward rotational moment of this arm is received by the swivel base. Therefore, if the boom tube 18 continues to be reduced, the counterweight 4 will move as shown by the chain line B in FIG. The counterweight can be suspended from a vehicle on the ground or in a pond, and by detaching the cable 16 from the pulleys 21 and 22, the counterweight can be transported independently.

Further, it is obvious that when the counterweight transported alone is suspended on the rear end of the swivel base 1, the operation described above can be performed in reverse.

In the illustrated pin connection mechanism (24, 25, 26), the pin hole 27 of the bracket 24 is made into a long hole because the counterweight 4 lifts the arm 9 via the stopper 28, so that the pin connection mechanism is not loaded. This is so that it can be easily seen or sensed.

In addition, in the above-described embodiment, when the arm 9 is raised or raised, the L at the tip of the arm 9 is
In order to prevent the lower end of the L-shaped stopper 28 from sliding relative to the engaging portion 32 at the top of the counterweight that engages with it, the upper end of the L-shaped stopper is pivoted 31 to the tip of the arm 9. The lower end fork-shaped portion 29 is always attached to the cable 1.
However, in place of the cross-shaped stopper 28, roller-type stoppers 34 facing the engaging portions 32 are provided as shown in FIGS. 3 and 4. The arm 9 is pivoted on the O-bracket 35 at the tip 36 so that the rotation center of the roller-type stopper 340 is located approximately above the vertical portion of the lifting cable 16 as shown in FIG. Good too.

According to the present invention, while the arm 9 is tilting up and down, the downward rotational force acting on the arm is received by the counterweight via the stopper at its tip, and when the arm 9 is supported to lie down on the swivel base. Since the downward rotating force is received by the swivel base, in combination with the separable connection mechanism between the arm 9 and the swivel base, the support 3 is This has the effect that the counterweight can be easily attached to and detached from the swivel base while remaining substantially upright without interfering with the counterweight.

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[Brief explanation of the drawing]

Figure 1 is a longitudinal side view, Figure 2 is the X when the arm is folded down.
The arrow view, FIG. 3, and FIG. 4 are views of other embodiments corresponding to FIG. 1 and FIG. 2, respectively. 1...Swivel base, 2...Telescopic boom, 3
...Receive money, 4...Counterweight,
6...Bolt, 9...Arm 11,
12... Pulley, 13... Support, 14.
...Pulley, 15...Cable guide board, 16...
...Counterweight lifting rope, 21, 22...
... Pulley, (24, 25, 26) ... Pin connection mechanism, 28°34 ... Stopper.

Claims (3)

[Scope of utility model registration request] (1) In a truck crane in which a counterweight that can be lifted in an almost upright state by a lifting cable is removably fixed to a support at the rear end of the swivel platform, the lifting cable can be tightened and loosened by the power device on the swivel platform. The arm, which has a pulley attached to its tip, can be tilted up and down between a counterweight lifting position where it is tilted rearward and upward, and a position where the counterweight is lowered and supported on the swivel base so that it is suspended and supported backwards from the holder. A separable coupling mechanism is mounted between the arm and the swivel base, and is pivoted on the swivel base to restrain the arm in the counterweight lifting position, and the top of the counterweight lifted by the lifting cable is connected to the swivel base. A stopper that engages regardless of whether the arm is tilted or raised is attached to the tip of the arm so that a downward rotational force is constantly applied to the arm due to the tension of the lifting cable before and after the pulley at the tip of the arm and the arm's own weight. A cable guide member that guides the lifting cable on the power unit side from a pulley at the tip is mounted on the swivel base so that the counterweight engaged with the stopper does not interfere with the receiver when the arm is raised or raised. Features a counterweight attachment/detachment device. (2) Utility model registration The counterweight attaching/detaching device according to claim (1), in which the coupling mechanism is a loose pin coupling mechanism. (3) Scope of claims for utility model registration, paragraph (1) or (2)
In the counterweight attachment/detachment device described in item 2), the stopper is pivoted at the tip of the arm so that the stopper at the tip and the top of the counterweight that engages with the stopper do not slide relative to each other when the arm is raised or raised.