JPH0340860Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a crane having a boom attached to a support.

Conventional technology A support is attached to the work equipment frame so that it can be raised and lowered, and a boom is connected to the support so that it can move up and down, and when the support is laid down, the boom is rotated up and down to take a position parallel to the support. A crane that can rotate.

Problems that the invention aims to solve: Because the boom has a heavy weight, mechanical force is required to rotate the boom relative to the support.

Means and action for solving the problem The center of gravity of the boom is positioned above the pivot pin that connects the support and the boom, so that even the boom, which has a large weight, can be easily rotated by human power. .

Embodiment Fig. 1 is an overall front view of a crane truck, and Fig. 2 is a plan view with the crane omitted. Crane 4 is attached to 3.

The crane 4 includes a strut 5 and a boom 6, and the strut 5 has second and third struts 8 and 9 fitted sequentially into a first strut 7 having a hollow rectangular cross section so as to be expandable and retractable using first and second cylinders (not shown). The boom 6 is inserted into the first boom 10 having a hollow rectangular cross section, and the second and third booms 11 and 12 are sequentially inserted into the first boom 10 so as to be extendable and retractable using cylinders (not shown).
A three-stage telescopic type in which a wire 15 is wound around a boom top sheave 13 and a hook sheave 14 attached to the tip of the third boom 12, and is wrapped around a winch 17 attached to the first boom 10 via a plurality of sheaves 16. A hook 18 is provided on the hook sheave 14, and first and second brackets 19 and 20 are fixed to the first boom 10, and the first bracket 19 and the third support 9 are fixed to the tip thereof. A pivot pin 22 is fitted across the bracket 21, and a fixing pin 23 is removably fitted between the second bracket 20 and the bracket 21, and by pulling out the fixing pin 23, the pivot pin The boom 6 is configured to rotate vertically with respect to the support column 4 about the axis 22.

The vehicle body 1 has four protrusions 25 integrally formed in a radial manner around the attachment part 24 of the turning mechanism 2, and each protrusion 25 has an attachment arm 26 that rotates in the horizontal direction with a vertical pin 27. An outer cylinder 29 of an outrigger device 28 is vertically fixed to each mounting arm 26, and an inner cylinder 30 is telescopically fitted into each outer cylinder 29 by a cylinder 31. At the same time, legs 32 are attached to the lower part of the inner cylinder 29, and the mounting arm 26 is locked in the outward protruding position shown by the solid line with a rod 33. It is rotated to the inner storage position shown by and fixed with a lock pin or the like (not shown).

A mounting bracket 34 is fixed to the two rear protrusions 25 of the vehicle body 1 toward the rear, and a wheel arm 36 supporting a wheel 35 is mounted to the mounting bracket 34 so as to be able to swing up and down with a pivot pin 37. By changing the pivot position of the other end of the support rod 38, the wheel arm 36 is locked in a ground contact position shown by a solid line and a retracted position shown by a phantom line.

The working machine frame 3 has front and rear brackets 41, 42 and an intermediate bracket 43 fixed to both sides of a plate-shaped base plate 40, and each of the front and rear brackets 41, 42 has a cylinder 44 and a long rear link 4.
One end of 5 is pivotally connected with pins 46 and 47, respectively,
One end of a short front link 48 is pivotally connected to each intermediate bracket 43 by a pin 49, and first and second support shafts 50,
51 is attached, the other end of the rear link 45 is pivotally attached to both sides of the first support shaft 50, and the second support shaft 51
A front link 48 and a piston rod 44a of the cylinder 44 are pivotally connected to both ends of the cylinder 44, respectively.

As a result, the strut 5 is attached to the work machine frame 3, and by expanding and contracting the piston rod 44a of the cylinder 44, the strut 5 is swung vertically between an upright vertical position shown by a solid line and a collapsed horizontal position shown by an imaginary line. The boom 6 is mounted and supported so that it can be displaced dynamically, and by pulling out the fixing pin 23, the boom 6 can be swung to a horizontal position parallel to the support column 5 as shown by the imaginary line. When in the posture, it is placed on the support stand 52.

The support column 5 and the work machine frame 3 are connected by a connecting device 5.
3, and this connecting device 53 is
A pedestal 54 fixed to the base plate 40, a presser lever 55 provided on the pedestal 54 so as to be swingable back and forth, a connecting pin 56 fixed to the lower end of the first column 7 of the column 5, and a presser lever 55 swingable. Locking mechanism 57
By pressing and holding the connecting pin 56 against the pedestal 54 with the presser lever 55, the column 5 and the work machine frame 3 are connected, and by separating the presser lever 55 from the connecting pin 56, the column 5 and the work machine frame 3 are connected. It is designed so that it can be separated from the work machine frame 3.

A mounting plate 57' is fixed to the side of the vehicle body 1,
First, second, third, and fourth operation valves 58 ₁ , 58 ₂ , 58 ₃ , 58 ₄ are attached to this mounting plate 57 ′,
First to fourth operating levers 59 ₁ , 59 ₂ , 5 respectively
9 ₃ and 59 ₄ are operated, and the supply of pressure oil to the cylinders 31 of each of the outrigger devices 28 is controlled.

Reference numeral 60 denotes a towing vehicle, which is provided with a funnel-shaped recess 62 into which a downward towed rod 61 fixedly attached to the vehicle body 1 is fitted;
1 is inserted from above so that it can be towed.

The center of gravity 6' of the boom 6 is located above the pivot pin 22 when the second and third booms 11 and 12 are retracted to a horizontal position, and
Even if the boom 6 is vertical when the support 5 is laid down, the center of gravity remains the same, and when the boom 6 is rotated from the vertical position to the horizontal position, the moment balance is reduced and the boom 6 can be easily rotated by human power.

Note that a hook receiver 70 is fixed to the outer wall of the first column 7 of the column 5, and the hook 18 is attached to this hook receiver 70.
The boom 6 may be rotated from a vertical position to a horizontal position by engaging the wire 15 and winding the wire 15 with the winch 17.

Effects of the invention By fitting the fixing pin 23, the boom 6 can be reliably supported horizontally on the upper part of the column 5, and when the boom 6 is used for crane work, the boom 6 can be attached to the column 5.
It does not move even slightly.

By removing the fixing pin 23, the boom 6 can be rotated around the pivot pin 22 to a vertical position, and the boom 6 can be rotated from a vertical position to a horizontal position, and the center of gravity of the boom 6 6' is the axis. Support pin 2
2, the moment balance is small, and even the boom 6, which has a large self-weight, can easily perform the above-mentioned boom rotation work manually.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view of a crane vehicle, and FIG. 2 is a plan view with the crane omitted. 3 is the work machine frame, 5 is the support column, 6 is the boom,
6' is the center of gravity position, 22 is the pivot pin.

Claims (1)

[Scope of utility model registration request] The lower part of the support column 5 is supported on the work machine frame 3 so as to be able to rise and fall freely, and a bracket 21 is attached to the tip of the support column 5, and one end of this bracket 21 and the boom 6 are attached.
A first bracket 19 of the boom 6 is connected to the first bracket 19 of the boom 6 so as to be vertically swingable, and a fixing pin 23 is connected to the other end of the bracket 21 and the second bracket 20 of the boom 6.
The crane is characterized in that the center of gravity 6' of the boom 6 is located above the pivot pin 22.