JPH075111Y2 - Crane jib undulating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a jib hoisting device for hoisting a jib extended at the tip of a crane.

[Conventional technology]

Conventionally, as a jib hoisting device for hoisting a jib by remote control from a driver's cab, as shown in FIGS. 7 to 10, a jib 2 extended from a tip portion (boom head) 11 of a boom 1 is By supporting the suspension mechanism 3 suspended between the jib 2 and the boom head 11, and expanding and contracting a single jib hoisting cylinder 31 incorporated in the suspension mechanism 3, the entire length of the suspension mechanism 3 is changed. A structure in which the jib 2 is raised and lowered is known.

In the suspension mechanism 3, an equalizer 33 is attached between the tip ends of a pair of left and right suspension rods 32, 32, and a jib hoisting cylinder 31 is attached to the equalizer 33 so that the suspension rods 32, 32 can be extended and retracted. The base ends of the jib hoisting cylinders 31 are attached to the upper surface of the jib on both left and right sides of the boom head 11.

[Problems to be Solved by the Invention] However, according to the conventional device for hoisting the jib 2 by adjusting the length of the suspension mechanism 3 with the single jib hoisting cylinder 31, the following problems occur. It was

(I) Since the jib hoisting cylinder 31 alone performs the jib hoisting motion, the thrust of the cylinder acts on the center line of the suspension mechanism 3 as shown in FIGS.
As shown in FIG. 10, the center of the suspension mechanism 3 in plan view,
That is, it is arranged at the center of the jib 2 in plan view.

However, since a wire rope (hereinafter, referred to as a jib rope) W for hanging the jib, which goes out from the boom head 11 toward the tip of the jib, is passed through the center of the jib 2 in a plan view, the jib rope W and the jib hoisting cylinder 31 are connected to each other. It is necessary to prevent interference.

Therefore, in the conventional device, as shown in FIGS. 9 and 10, rope guide members (guide rollers or guide sheaves) 34 and 35 are provided on both front and rear sides of the jib hoisting cylinder 31, and the jib rope W and the jib hoisting cylinder 31 are connected. Although a gap is secured between the guide members 34 and 35, the jib rope W is worn earlier.

Further, since the equalizer 33 and the rope guide members 34, 35 are required as accessory parts for the jib hoisting cylinder 31, the weight of the suspension mechanism 3 is heavy for a single jib hoisting cylinder 31. .

(II) Since the jib hoisting operation has to be performed by a single jib hoisting cylinder 31, the diameter of the cylinder 31 becomes large, and when the jib 2 is stored so-called vertically on the side surface of the boom, the above cylinder diameter is large, The amount of protrusion of the jib 2 to the side of the boom increases. For this reason, workability in a narrow space is deteriorated during crane work while the jib is stored.

(III) The jib 2 is usually an outer jib 21 as shown.
And the inner jib 22 slidably fitted into the outer jib 21 so that the length can be changed.

In this two-stage jib, in order to reduce the sliding resistance of the inner jib with respect to the outer jib, it is usual to provide a lower guide roller at the lower end of the outer jib and an upper guide roller at the intermediate upper part.

However, in the case of the conventional device, the jib hoisting cylinder 31 is located at the installation position of the upper guide roller, and interference occurs between the upper guide roller and the jib hoisting cylinder 31. Therefore, as shown in FIG. It is unavoidable to replace the upper guide roller with a flat pad 23 having a small upward protrusion amount. In FIG. 9, reference numeral 24 is a lower guide roller.

Therefore, the sliding resistance of the inner jib 22 increases,
The operation becomes heavy when the inner jib 22 is pulled out or pushed in from the outer jib 21.

The problem of (III) can be solved by providing a jib undulating cylinder on the base end side of the suspension rod as shown in Japanese Utility Model Laid-Open No. 63-175688.

However, in this case, a troublesome operation of attaching and detaching the jib hoisting cylinder to and from the tip of the boom is required, which is a bad idea.

Therefore, the present invention is premised on the configuration in which the jib undulation cylinder is provided on the tip side of the suspension rod, and there is no risk of interference between the jib undulation cylinder and the jib rope, or interference with the cylinder upper guide roller in the case of a two-stage jib. (EN) A crane jib hoisting device capable of reducing the amount of protrusion of the jib to the side of the boom during storage.

[Means for Solving the Problems]

According to the present invention, a pair of left and right suspension members are suspended between a boom tip and a jib extended from the boom tip to form a suspension mechanism for supporting the jib. Each of the suspension rods has a base end portion attached to the tip end portion of the boom, and a jib hoisting cylinder attached between the tip end portion of the suspension rod and the jib.

[Action]

In this way, the pair of left and right suspension rods are respectively attached with jib hoisting cylinders to form separate left and right suspension members, and both suspension members are suspended between the boom tip and the jib to form a suspension mechanism. Therefore, the jib undulating cylinders are located on the left and right sides of the jib in a plan view.

Therefore, there is no risk of interference between the jib undulation cylinder, the jib rope, and the upper guide roller in the case of a two-stage jib.To prevent this interference, a rope guide member is provided or the upper guide roller is replaced with a pad. There is no need. Therefore, it is possible to prevent the jib rope from being worn by the rope guide member, and it becomes easy to carry out the operation of taking in and out the inner jib when changing the length of the jib.

Further, since the cylinder load of the jib hoisting cylinders is shared by the cylinder load at the time of hoisting the jib, the cylinder diameter of the jib hoisting cylinder can be reduced, so that the amount of jib protruding from the lateral side of the boom when the jib is stored can be suppressed to be small.

〔Example〕

 An embodiment of the present invention will be described with reference to FIGS.

1 to 4 show the jib extended state, and FIGS. 5 and 6 show the stored state.

Suspension mechanism 4 that supports the jib 2 in an extended state
The pair of left and right suspension members 5 and 6 is the boom head 1.
It is constructed by being suspended between 1 and jib 2.

The left and right suspension members 5 and 6 are configured to be extendable and contractible by axially connecting suspension rods 51 and 61 and jib hoisting cylinders 52 and 62, respectively.

More specifically, the ends of the suspension rods 51 and 61 are connected to the respective rod ends of the jib hoisting cylinders 52 and 62 via horizontal horizontal pins 53 and 63 so as to be rotatable about the same pins. The base ends of the cylinders 52 and 62 are attached to brackets 21a and 21b provided on the left and right ends of the outer jib 21 of the jib 2, respectively, and the suspension rods 51 and 61.
The base ends of the two are pin-connected to the left and right sides of the boom head 11 so as to be rotatable about horizontal horizontal axes.

Thus, with the suspension members 5 and 6 positioned on the left and right sides of the jib 2 in a plan view, the boom head 11 and the shib 2
Suspended between the jib undulating cylinders 52,62
The length of the suspension mechanism 4 as a whole is changed by the expansion and contraction operation of the jib 2, and the jib 2 is configured to oscillate with the connection point to the boom head 11 as a fulcrum.
The jib hoisting cylinders 52 and 62 are driven by a known hydraulic tuning circuit (not shown) so that they simultaneously expand and contract by equal amounts.

As described above, since the jib 2 is supported by the suspension mechanism 4 having a two-cylinder structure in which the jib undulating cylinder is divided into the left and right, the jib 2 passing through the jib center in plan view, and There is no risk of the upper guide member slidably supporting the upper surface of the inner jib 22 of the jib 2 interfering with the suspension mechanism 4.

Therefore, since the rope guide members 34 and 35, which were required in the conventional device (FIGS. 9 and 10), are not required in this device,
Wear of the jib rope W due to these guide members is prevented. Further, as the upper guide member of the inner jib 22, it is possible to provide the guide roller 25 having a large upward protrusion amount, so that the pulling-out and pushing-in operation of the inner jib 22 at the time of changing the jib length becomes easy.

Moreover, since the equalizer 33 and the jib rope guide members 34 and 35 of the conventional device (FIGS. 9 and 10) are unnecessary, the weight of the suspension mechanism 4 as a whole is reduced by using the two jib hoisting cylinders 52 and 62. It is almost the same as the suspension mechanism 3 of.

On the other hand, when the jib is stored, the suspension mechanism 4 is stored together with the jib 2 on the side surface of the boom with the base ends of both suspension rods 51 and 61 removed from the boom head 11.

A pair of left and right cylinder holding brackets 26, 26 are provided on the upper surface near the tip of the outer jib 21 in order to hold the jib undulating cylinders 52, 62 on the jib 2 during storage. This cylinder holding bracket 26, 26 has a jib undulating cylinder 5
A notch 26a that engages from the jib tip side is provided on the connecting pins 53 and 63 of the cylinders 52 and 62 and the suspension rods 51 and 61 when the jib is retracted when the jib is retracted when the jib is retracted. The cylinders 52 and 62 are held by the jib 2.

In the jib retracted state, the suspension mechanism 4 has the jib hoisting cylinders 52 and 62 located between the boom 1 and the jib 2 and the suspension rods 51 and 61 located on the jib 2 as shown in FIGS. It is stored in a state of conformity.

In this case, the jib undulating cylinders 52 and 62 share the load when the jib is undulating, so that the cylinder diameter is smaller than that of the jib undulating cylinder 31 in the conventional single cylinder type. Therefore, the space for storing the cylinder, which should be secured between the boom 1 and the jib 2, can be small, so that the amount of protrusion of the jib 2 to the side of the boom can be reduced.

In FIG. 6, 7 and 8 are known jib holding devices that hold the jib 2 in the storage position.

[Effect of device]

As described above, according to the present invention, the left and right suspension rods are connected to the tip end side of the jib hoisting cylinders to form separate left and right suspension members, and the jib hoisting cylinders are located on the left and right sides of the jib in plan view. In this state, both suspension members are suspended between the boom tip and the jib to form a suspension mechanism, so there is no risk of interference between the jib hoisting cylinder, the jib rope, and the upper guide roller in the case of a two-step jib. . Therefore,
As a measure to prevent this interference, it is no longer necessary to provide a rope guide member or change the upper guide roller to a pad as in the past, so it is possible to prevent the jib rope from being worn by the rope guide member and to use the inner jib when changing the jib length. It becomes easy to put in and take out.

Further, since the cylinder load of the jib hoisting cylinders is shared by the cylinder load at the time of hoisting the jib, the cylinder diameter of the jib hoisting cylinder can be reduced, so that the amount of jib protruding from the lateral side of the boom when the jib is stored can be suppressed to be small. As a result, the lateral field of view during traveling of the crane and the narrow area traveling property are improved.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention with a jib extended, FIG. 2 is a plan view of the same, and FIG. 3 is a partially enlarged view of FIG.
FIG. 4 is a partially enlarged view of FIG. 2, FIG. 5 is a side view of the jib stored state, FIG. 6 is a plan view of the same, and FIG. 7 is a first example showing a conventional example.
FIG. 8 is a view corresponding to FIG. 2, FIG. 8 is a view corresponding to FIG. 3, FIG. 9 is a view corresponding to FIG. 3, and FIG. 10 is a view corresponding to FIG. 1 ... Boom, 2 ... Jib, 4 ... Suspension mechanism, 5,6 ... A pair of left and right suspension members that make up the suspension mechanism, 51,61 ... Suspension rods that make up the suspension member, 52,62 ... The same jib undulating cylinder.

Claims (1)

[Scope of utility model registration request] 1. A pair of left and right suspension members are suspended between a tip portion of a boom and a jib extended from the boom tip portion to form a suspension mechanism for supporting the jib. Is a jib of a crane characterized in that it is configured to be extendable by a suspension rod whose base end is attached to the boom tip and a jib hoisting cylinder attached between the tip of the suspension rod and the jib. Undulation device.