JPS6119195Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a floating crane that can be stored on a ship by flipping the jib of a non-swivel crane from the bow side to the stern side. The present invention relates to a floating crane in which an auxiliary hoisting rope provided on the tip side of the jib follows the movement of the jib during the work of storing or restoring the jib so that it can be automatically retracted and retracted without loosening.

[Conventional technology]

As a floating crane, a hook 4 hanging down via a hoisting rope 3 from the top 2a of a jib 2, which is provided near the bow 1a so as to be able to rise and rise freely, as shown in FIG. 1, is attached to a hook locking member 5 on the bow 1a. latched to,
While loosening the hoisting rope 3, the elevating rope 6 engaged with the top 2a of the jib 2 is unwound, and the jib 2 is moved to the stern section 1.
Floating crane (Utility Model Publication No. 55-36477 )It has been known.

[Problem that the invention attempts to solve]

By the way, an auxiliary hoisting rope 8 having an auxiliary hoisting hook 7 at the tip for auxiliary cargo handling is stretched on the tip side of the hoisting rope 3 in the jib 2, and the hoisting rope 3 side is configured for main cargo handling. In this case, when the jib 2 is stored or restored to its original position, a problem will occur if the auxiliary hoisting hook 7 is suspended, so the auxiliary hoisting hook 7 is also locked with the hook locking member 5 together with the main hoisting hook 4. However, in this case, in response to rotating the jib 2 by operating the main hoisting rope 3 and the elevating rope 6, the auxiliary hoisting rope 8 is also unwound and retracted in parallel, and its length is adjusted. Adjustments had to be made, making the operation complicated and resulting in poor workability.

In addition, the auxiliary hoisting rope 8 is located closer to the tip of the jib 2 than the main hoisting rope 3, and since it is intended for light load handling, it is several times faster than the winding and unwinding speed of the main hoisting rope 3. When storing or restoring the auxiliary hoisting rope 8, indirect effort is required to adjust the speed of the auxiliary hoisting rope 8 to the moving speed of the jib 2, and if the relative speed with the main hoisting rope 3 is incorrectly adjusted, the auxiliary hoisting rope 8 may exceed the allowable value. Since a load exceeding
There was a risk of damage to the auxiliary winch 10, etc.).

The present invention was devised to solve the above-mentioned problems of the conventional floating crane. The purpose of this invention is to enable the auxiliary rope installed at the tip of the jib to follow the movement of the jib and automatically feed in and out without loosening it, thereby improving operability and workability. And to provide a floating crane that can prevent damage to surrounding members.

[Means for solving problems]

The present invention includes a jib that is installed near the bow of the ship so that it can be raised and raised freely, a rope that is engaged with the top of the jib, and
A main hoisting rope that has a main hoisting hook at the tip and is stretched on the jib, and an auxiliary hoisting rope that has an auxiliary hoisting hook at the tip and is stretched on the jib on the tip side of the main hoisting rope. , a hook locking member provided on the bow section to detachably lock the main hoisting hook and the auxiliary hoisting hook, and a jib support stand provided on the stern section to support the top side of the jib. The main hoisting hook and the auxiliary hoisting hook are locked to the hook locking member, the main hoisting rope and the auxiliary hoisting rope are loosened, the elevating rope is wound in, and the jib is rotated to the stern side to be placed on the hull. In the floating crane configured to be stored, a hydraulic motor for rotationally driving the auxiliary hoisting winch in the winding direction of the auxiliary hoisting rope is connected to the winding drum of the auxiliary hoisting winch that performs the winding-in and unwinding operation of the auxiliary hoisting rope, and the hydraulic motor The oil supply pipe is equipped with a relief valve that releases part of the hydraulic pressure in the oil supply pipe to allow the winding drum to stop or reverse when the tension applied to the auxiliary winding rope exceeds a predetermined tension.

[Operation] The winding drum winds up the auxiliary winding rope, but when the tension exceeds a predetermined tension, a part of the hydraulic pressure is released by the relief valve and the rotation is stopped.When the tension increases further, the rotation is forcibly reversed. He was forced to let out a supplementary rope.

〔Example〕

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 2, a bracket 12 is provided on the deck 11 near the bow portion 1a of the hull 1, and the base 2b of the jib 2 is pivotally attached to the bracket 12 via a pin 13 to support the jib 2 so as to be able to move up and down. do.

The jib 2 constitutes a non-rotating crane that rotates from the bow portion 1a side to the stern portion 1b side through the zenith.

The main rope 3 is connected to the sheave 1 at the top 2a of the jib 2.
4, and one end of this main hoisting rope 3 is connected to the main hoisting winch 1 installed in the center on the deck 11.
5, and a main hoisting hook 4 is suspended from the other end of the main hoisting hook 4 via a sheave 16 for main cargo handling. Further, an auxiliary hoisting rope 8 is stretched across a sheave 9a on the top side of the main hoisting rope 3 at the top 2a of the jib 2, and one end of this auxiliary hoisting rope is placed behind the main hoisting winch 15 on the deck 11. It is wound and fixed around the installed auxiliary hoisting winch 10, and at the other end, an auxiliary hoisting hook 7 for auxiliary cargo handling is suspended via a sheave 9b.

The winding drum 19 of the auxiliary winding winch 10 has a tension adjustment mechanism 1 that can set and adjust the retracting tension and the retracting force.
7 are connected to each other, and this tension adjustment mechanism 17 has a configuration to be described later, so that when the tension applied to the auxiliary winding rope 8 is less than or equal to the set retracting tension, the auxiliary winding rope 8 is retracted, and when the tension is greater than or equal to the set retracting tension, the tension adjustment mechanism 17 retracts the auxiliary winding rope 8. It is configured like a so-called automatic tension winch mechanism that lets out the auxiliary winding rope 8 and holds the retracting and unwinding movement of the auxiliary winding rope 8 in a stopped state when the tension is between the set retracting tension and the set unwinding force. . Next, the details of the tension adjustment mechanism 17 will be explained based on FIG. 3.

In the illustrated example, an electrohydraulic tension adjustment mechanism 1 detects the tension of the auxiliary hoisting rope 8 with a relief valve 18 and automatically performs the loading and unwinding operations of the winding drum 19.
7 has been adopted. That is, a hydraulic motor MF is connected to the winding drum 19, a hydraulic pump PF is connected to the electric motor EM, and the hydraulic pump PF and the hydraulic motor MF are connected through an oil supply pipe 20. The oil suction pipe 21 of the hydraulic pump PF is connected to an oil tank 22, and a hydraulic motor MF is also connected to this oil tank 22.
A drain oil pipe 23 is connected thereto. The oil supply pipe 20 and the oil drain pipe 23 are communicated with each other by a bypass pipe 24, and the bypass pipe 24 has a pressure adjustment mechanism that releases the oil pressure when the oil pressure on the oil supply pipe 20 side exceeds a predetermined value. A relief valve 18 is provided. Therefore, the oil is always sent in the direction in which the winding drum 19 reels in (takes up) the auxiliary winding rope 8, so when the rope tension (the tension generated in the auxiliary winding rope 8) is small, the winding drum 19 winds up the auxiliary winding rope 8. However, as the rope tension increases and the accompanying torque of the hydraulic motor MF increases, the oil pressure inside the oil supply pipe 20 rises and reaches a predetermined pressure, and the relief valve 18 operates, causing the rotation to continue. The trunk 19 stops rotating while maintaining the rope tension at a predetermined value. When the rope tension increases further, the hydraulic motor MF is reversed against the hydraulic pressure, and thereby the winding drum 19 is forcibly rotated in the direction in which the auxiliary winding rope 8 is unwound. In this case, since the hydraulic motor MF works to send oil backwards by pumping, as the feeding speed of the hoisting drum 19 increases, the amount of oil passing through the relief valve 18 increases, and due to the resistance, the amount of oil flowing through the oil supply pipe 20 side increases. As the oil pressure increases, the rope tension will increase proportionately.

The operating characteristics of such tension adjustment mechanism 17 are as follows.
As shown in the figure, P ₁ is the rope tension when the winding drum starts retracting, P ₂ is the rope tension when the winding drum 19
is the rope tension when starting to pay out.

The tension adjustment mechanism 17 having the above-described configuration is operated only when the jib 2 is rotated to be retracted or erected and restored, and is in a dormant state during normal crane cargo handling operations. For this reason, the winding drum 19 of the tension adjustment mechanism 17 is commonly used as the winding drum of the auxiliary winding winch 10 as shown in FIG. 3 so that crane work can be carried out under normal conditions.

On the other hand, the main winding hook 4 is formed with a pin hole 25 for connecting cargo handling fittings, etc., and the auxiliary winding hook 7 is also formed with a similar pin hole 26.

A bracket-shaped hook locking member 5 for locking the main hoisting hook 4 and the auxiliary hoisting hook 7 is provided on the deck on the side of the bow portion 1a. A hook pin 27 is provided for fitting into the pin hole 25 of the auxiliary winding hook 7 and the pin hole 26 of the auxiliary winding hook 7 to fix these.

A sheave 28 is pivotally supported on the top portion 2a of the jib 2, and an elevating rope 6 is stretched over the sheave, and the jib 2 is elevated by expanding and contracting the elevating rope 6. One end of the elevating rope 6 is locked onto a jib support stand 29 installed on the stern part 1b, and the other end engages with the sheave 28 of the jib 2, and the guide sheave 30 installed on the jib support stand 29 is engaged. It reciprocates and reaches the elevating winch 31, where it is wrapped and fixed. This elevating winch 31 is installed on the deck 11 on the rear side of the auxiliary hoisting winch 10.

The jib support stand 29 supports the jib 2 when it rotates toward the stern part 1b and falls down, and supports it in the retracted state. A receiving portion 32 made of an elastic material is provided for cushioning support.

Next, a method for storing the jib 2 on the hull 1 and a method for operating the floating crane constructed as described above will be explained with reference to FIG. 5.

As shown in the figure, the jib 2 is in the crane operation state when it is in position A, and the jib 2 is placed on top of the hull 1 at the top 2.
When the jib 2 is in the position A, the main hoist hook 4 and the auxiliary hoist rope 8, which are respectively supported by the main hoist rope 3 and the auxiliary hoist rope 8, are Both auxiliary winding hooks 7 are locked to the hook locking member 5. In addition, in the case of a safe state with no wind, the jib 2 may be raised to the nearly upright position F and then locked. Then, the pin holes 25, 26 of the respective hooks 4, 7 are fitted into the hook pins 27 of the locking member 5 to ensure locking.

Next, the retraction starting tension P ₁ of the tension adjustment mechanism 17 is set to a low value by adjusting the relief valve 18 to perform a retraction operation under a light load. In this case, the reeling speed of the auxiliary hoisting rope 8 is set to a relative reeling speed that approximately corresponds to the moving speed ratio of the jib 2, and the magnitude of the external force (rope tension) applied to the auxiliary hoisting rope 8 is set to the set reeling tension _P1 . When the tension exceeds this and reaches the payout start tension _P2 , the auxiliary winding rope 8 is fed out. At the same time, the main winding winch 15
While the main hoisting rope 3 is loosened by the unwinding operation, the elevating rope 6 is pulled by the winding operation of the elevating winch 31, and the jib 2 is rotated from the bow section 1a side to the stern section 1b side. During the rotation process of the jib 2, the auxiliary rope 8 is subjected to an external force in the pulling direction, and when the rope tension reaches the unwinding start tension _P2 , the tension adjustment mechanism 17 is forcibly rotated in the unwinding direction. As a result, the auxiliary winding rope 8 is automatically let out by following the movement of the jib 2 by the relative length of the momentum of the jib 2. Therefore, the external force applied to the auxiliary winding rope 8 due to the movement of the jib 2 is relaxed or absorbed by the feeding, so there is no risk of damage to the auxiliary rope 8, and damage to surrounding members such as the jib 2 can be prevented. Note that when the auxiliary winding rope 8 is paid out, the hydraulic motor MF, which is the driving part of the tension adjustment mechanism 17, is reversed against the hydraulic pressure, so that a predetermined tension is applied to the auxiliary winding rope 8. , the auxiliary winding rope 8 is not loosened.

In this way, the jib 2 moves from positions A to B and C, and finally collapses to the retracted position D, where it is supported on the jib support stand 29. When the floating crane is towed or sailed to a remote location, the jib 2 is securely bound by the lashing device at the receiving portion 32 of the jib support base 29.

On the other hand, when you reach your destination such as a work site,
The auxiliary winding drum 17 is operated in the same manner as described above, and at the same time winds up the main winding rope 3, and at the same time winds up the elevation rope 6.
By unwinding the auxiliary winding rope 8,
follows the movement of the jib 2 from the storage position D to the crane working position A, and is automatically retracted without slack in order to generate rope tension by the retracting operation of the tension adjustment mechanism 17. The jib 2 is restored to the crane working position A, and the work can be started immediately.

In the above embodiment, an electro-hydraulic automatic tension winch with a pressure adjustment valve was used as the tension adjustment mechanism 17, but the auxiliary drum may be a hydraulic automatic tension winch with an automatic oil amount adjustment mechanism or a hydraulic cylinder system. A winch or other mechanism such as an electric automatic tension winch may be employed.

[Effect of idea]

In summary, the present invention provides the following excellent effects.

(1) Since the auxiliary hoisting rope can be let out when its tension exceeds a predetermined tension, the auxiliary hoisting rope can be automatically fed in and paid out following the movement of the jib without loosening.

(2) In addition, by being able to forcibly let out the auxiliary winding rope, external forces acting on the auxiliary winding rope can be absorbed, making it possible to prevent damage to the auxiliary winding rope as well as its surrounding components. , durability and safety can be improved.

(3) Therefore, when storing the jib and restoring it to its original position, it is possible to focus only on the main hoisting rope and the elevating rope, thereby improving operability and work efficiency compared to the conventional method.

(4) Since the structure is extremely simple, it is easy to manufacture and can also be easily adopted in conventional cranes of this type.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a conventional floating crane, FIG. 2 is a side view showing an embodiment of the floating crane according to the present invention, FIG. 3 is a configuration explanatory diagram showing the drive mechanism of the tension adjustment mechanism, and FIG. The figure is a graph showing the operating characteristics of the tension adjustment mechanism, and FIG. 5 is a side view showing the state of rotation of the jib. In the diagram, 1 is the hull, 2 is the jib, 3 is the main rope,
4 is a main winding hook, 5 is a hook locking member, 6 is an elevation rope, 7 is an auxiliary winding hook, 8 is an auxiliary winding rope, 10
1 is an auxiliary winding winch, 17 is a tension adjustment mechanism, and 29 is a jib support stand.

Claims (1)

[Scope of utility model registration request] A jib that is installed near the bow so that it can be raised and raised freely; a lifting rope that is engaged with the top of the jib; a main hoisting rope that has a main hoisting hook at its tip; and a main hoisting rope that is stretched on the jib; An auxiliary hoisting hook is provided at the bow of the ship, and the auxiliary hoisting rope is stretched from the main hoisting rope to the jib on the tip side, and the main hoisting hook and the auxiliary hoisting hook are detachably engaged. and a jib support stand provided on the stern portion to support the top side of the jib, and the main hoist hook and the auxiliary hoist hook are engaged with the hook anchor member to prevent the main hoist from being moved. An auxiliary hoisting winch for winding in and unwinding the auxiliary hoisting rope in a floating crane that winds up the elevating rope while loosening the rope and the auxiliary hoisting rope, and rotates the jib toward the stern and stores it on the ship's hull. A hydraulic motor is connected to the winding drum to rotate the auxiliary winding rope in the winding direction of the auxiliary winding rope, and when the tension applied to the auxiliary winding rope exceeds a predetermined tension, a part of the hydraulic pressure in the oil supply pipe is removed. A floating crane is equipped with a relief valve that opens to allow the winding drum to stop and reverse.