JPH0262474B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application: The present invention relates to a crane of both horizontal and undulating type, which can be used either in a horizontal state or in an undulating state.

Background of the Invention: Various types of cranes have been developed and put into practical use for use in lifting and lowering materials and equipment at construction sites, etc., but generally there are horizontal boom cranes and undulating boom cranes. There are different types, and each model is selected and used depending on the conditions of the work site. Both types have their own features; for example, horizontal boom cranes can move loads horizontally, so they can be transported over a relatively wide range, and they can be retracted at a constant lifting height. On the other hand, at a construction site, etc., the mast must be erected higher than the structure to be constructed, so the cost increases due to the height of the mast, and there is not enough space for installation (work space). There are drawbacks that make it unsuitable for use.
On the other hand, jib hoisting cranes can raise and lower the jib (boom) to perform hoisting and lowering operations, so when installing the mast, the height can be lower than that of the horizontal boom cranes to achieve the desired purpose. Since the turning radius is small, it can fully demonstrate its function even in sites with narrow installation space (work space), but on the other hand, the working range is naturally narrower, and the lifted load displaces vertically when lifting, making it difficult to handle. This requires care and the jib must be raised and lowered each time the mast is added, which increases the working time and makes climbing work inconvenient.

In this way, the horizontal boom type and the undulating boom type each have their advantages and disadvantages, so in reality, two types of cranes are available, and the most convenient model is selected and used depending on the situation at the construction site. Therefore, in some cases, the operational period of the crane is short, and the cost of maintaining the crane in a warehouse for storage when not in use increases, resulting in a large economic loss.

Purpose of the invention: The present invention has been made in view of the above-mentioned situation, and it is possible to arbitrarily select either the horizontal type or the undulating type depending on the conditions of the work site where one crane is used. However, the goal is to provide something that has functions that can be switched and used.

Structure of the invention: The crane of the present invention has a main frame whose front side is open at the upper center of the turning table, which is mounted on a frame body equipped with a climbing mechanism at the top of the mast. A boom support body is attached to the top of the main frame, and the boom support body is attached to the main frame via a pivot shaft to maintain the boom horizontally when it is laid down and to allow it to be raised and lowered. A trolley is attached so that it can move freely between the pivot point and the tip end, and the traversing of the trolley and the lifting and lowering of a hanging pulley with a hook hanging from the trolley are operated by a winch mounted on a turning platform, and such boom The main frame is connected to both sides of the main frame at an appropriate dimension forward position from the pivot point of the boom, and a buffer means for raising the boom is attached to the back of the main frame.

Further, in the present invention, a locking device for fixing the trolley is attached to the tip of the boom, so that the trolley is fixed when the boom is used by raising and lowering it.

In the present invention, the mast segment is suspended inside the main frame from the open front surface of the main frame by traversing the trolley at an elevation angle of about 20 degrees from horizontal to the boom, and mast addition work during climbing is performed. It is made possible.

Furthermore, in the present invention, a stopper is provided at the top of the main frame that can limit the lower limit when the boom is in a horizontal state, so that the linear actuator for uphilling can be stopped, and the main body can be fixed with a locking pin if necessary. I made it possible.

Embodiments Next, the crane of the present invention will be described in detail with reference to embodiment drawings.

Fig. 1 shows the crane of the present invention when the boom is kept in a horizontal state, and an outer mast 2 equipped with a climbing mechanism 3 is fitted onto the upper part of a mast 1 having a well-known structure, and the upper end of the outer mast 2 is shown in Fig. 1. A mast hanging hole is provided at the upper part of the mast at a required radius from the center of rotation on the upper surface of the turning table 4, which is provided so as to extend an appropriate length through a turning ring attached to the mast. A main frame 5 is erected at a height that allows one segment of the mast to be suspended across the main frame, and the front side of the main frame 5 can be kept open or the horizontal members can be removed only during climbing work. It is constructed in such a way that it has sufficient strength. A bracket 6 is provided on the top of the main frame 5 so as to protrude toward the rear end (it is preferable to provide two brackets in parallel at appropriate intervals), and a boom 10 of a required length is provided. The mounting piece 12 protruding downward from the lower surface of the main body 11 is engaged with the bracket 6 and connected to the pin 7 at a ratio of approximately 5.5:1 (based on the position of the pivot pin 7). (It is not limited to this) They are distributed in the front and rear and are installed so that they can be raised and lowered from horizontal to appropriate angles of elevation.

The boom 10 is a framed structure, and guide rails 13 are attached to both sides of the main member disposed on the lower side in a horizontal state, extending from the pivot portion to the front end, so that the boom 10 can freely move horizontally along the guide rails 13. A trolley 14 is suspended from the swivel 14, and this trolley 14 is run by a traversing cable 16 operated by a traversing endless machine 15 installed on the turning table 4, and pulleys 14',
The suspension rope 18 that raises and lowers the hanging pulley block 17 with a hook that hangs down via the hook 14' is moved along a course almost the same as the traversing rope 16 via a pulley provided on the upper part of the main frame 5 by a hoisting machine 19 installed on the turning table 4. A known method is adopted in which the suspension rope is wound around the pulley block 17, and the end of the suspension rope is connected to an overload detector 20 mounted on the upper part of the main frame 5.

In this way, the main frame 5 of the boom 10
Support plates 22 are appropriately attached to both sides of the pivot portion, that is, a slightly forward position of the base portion 11, and a bracket or trunnion 2 is attached to the support plate 22 with the base fixed to the support plate 22.
3 and a mounting piece 24 attached to the front upper part of the main frame, the base end of the linear actuator (hydraulic cylinder 25 in the embodiment, hereinafter referred to as the luffing drive cylinder) and the actuating rod end are connected with pins, respectively. so that the piston rod 25' of this drive cylinder 25 is kept horizontally to the boom 10 in the most retracted state, and the boom 10 stands up at its highest when the piston rod 25' is fully advanced. The stroke is determined so that the boom 10 can be raised and lowered, and the driving cylinders 25 are disposed on both sides of the pair of booms 10 to perform raising and lowering operations. A counterweight (not shown) is attached to the rear end of the boom 10 to assist the operation of the boom when it is raised or lowered. Further, both drive cylinders 25 are operated by the control system so as to operate in synchronism.

Further, on the rear side of the main frame 5, as shown in FIG. 2, a buffer means 30 is provided to set the limit when the boom 10 is raised to its maximum elevation angle, and to absorb the reaction force when the boom 10 is raised. For example, a combination of a hydraulic damper or a coil spring, a supporting mechanism, and a contact plate is attached to the rear side of the main frame 5, and the contact plate is a main member of the boom 10 or a support plate provided at a corresponding position. It is arranged so that it is in contact with.

In addition, a fixing device for the trolley 14 is attached to the tip of the boom 10 at a predetermined position for use when the boom 10 is raised and lowered. A limit switch is attached at the most advanced position along the trolley, and the trolley 14 can be fixed only when this switch is activated. , those operated by electric power, hydraulic pressure, etc. are provided. Note that, on the trolley 14 side, a device with a locking hole, a clamp shaft, etc., corresponding to the type of the above-mentioned fixing device is used.

According to the crane of the present invention configured as described above, it is possible to select whether to use the boom 10 in a horizontal state or in an undulating state depending on the conditions of the work site where it is installed. As shown in FIG. 1, the piston rod 2 of the drive cylinder 25
By retracting the boom 5' to its fullest extent, the boom 10 is supported by the pivot pin 7 and both drive cylinders 25 without being tilted from the horizontal, allowing the crane to operate in a horizontal state. In this state, the trolley 14 is attached to the guide rail 13 of the boom 10.
It can move freely along the road by operating the endless machine 15, and can be operated in the same way as a conventional horizontal boom type crane.

Next, when using the boom 10 by raising and lowering it,
Move the trolley 14 to the extreme end of the boom 10 in a horizontal or slightly elevated state, actuate a limit switch (not shown), and move the trolley fixing device to fix the trolley 14 to the boom 10 ( When erecting the crane without activating the climbing mechanism, the trolley fixing device may be activated first to secure the trolley to the end of the boom). In this state, a control circuit is used to prevent the endless traversing machine 15 from operating, and the drive cylinder 25 is operated to raise and lower the boom 10 with the pivot pin 7 as the base point, and to arbitrarily change the working radius. By operating the suspension rope 18 by the hoisting machine 19, it can be used in the same way as a conventional undulating crane. Even if the boom 10 is erected with the load suspended in this state, the shock absorbing means 30 is attached to the rear side of the main frame 5, so even if the boom 10 is supported by its main body 11, this The shock absorbing means 30 limits the boom 10 to its standing limit and buffers and absorbs the reaction force on the rear side due to excessive lifting, thereby preventing accidents such as the boom 10 reversing or buckling due to vibration. can do.

As the work progresses, the lifting height increases, and if it becomes necessary to perform climbing work, the boom 10 moves the trolley 14 sideways along the guide rail 13 within a range of about 20° from horizontal to elevation. , move the mast segment 1' lifted from the required position to the front side of the main frame 5 as shown by the chain line A in Figure 1, and before this work, remove the horizontal members etc. to open the main frame 5 with the front side open. Move the trolley 14 to the inside of the existing mast 1 as shown by the chain line A, hang and connect the mast segment 1' so that it matches the center of the existing mast 1, and operate the climbing mechanism 3 in a well-known manner to ascend. are repeated in sequence until the required height is reached. When disassembling, do this in reverse order.

In addition, the vicinity of the connecting pivot between the boom and the main frame, for example, the pivot pin 7 in the above embodiment.
On the main frame 5 at an appropriate distance forward from the connection position, lock the protrusion protruding from the lower surface of the boom 10 and the bracket or similar device protruding from the upper surface of the main frame to ensure that the boom 10 is in a horizontal state. If a safety means is provided to keep the boom stable by fixing it only when used in a horizontal boom, the load on the drive cylinder 25 can be eliminated and the boom can be used as a horizontal boom crane. As for the means for fixing the boom, in addition to manual operation, an automatically operated locking device may be attached to the upper surface of the main frame and may be incorporated by remote control so that it can be operated only when necessary.

In addition to the above-described structure, the structure of the connecting pivot between the boom and the main frame includes coaxial pins protruding from both sides of the boom main body, and a bracket supporting the pins on the main frame side. It may also be constructed so that it can be raised and lowered as it is attached. Furthermore, regarding the tilting of the boom during climbing, it is preferable to determine the usage limit while the trolley is in a state where it can move sideways.

Effects of the invention: As described above, the crane of the present invention operates the drive cylinder (linear actuator) to move the actuating rod (piston rod) forward and backward according to the work situation.
This method can be selected as a method that keeps the boom horizontal and has a large working radius so that cargo can be lifted and lowered over the entire area, or as a method that can be used in a relatively narrow site where the boom is raised and lowered for lifting and lowering work. Since one crane can be used as two types of cranes, it can be used effectively without being idle, and the structure is simple and does not complicate handling in any way, increasing economic efficiency. It's something you get.

[Brief explanation of the drawing]

The drawings show one embodiment of the construction crane of the present invention, in which Fig. 1 shows the case where the boom is kept in a horizontal state, and Fig. 2 shows a case where the boom is kept in an undulating state. It is. 1... Mast, 2... Outer mast, 3... Climbing mechanism, 4... Turning table, 5... Main frame, 6... Bracket, 7... Pivot pin, 10...
...Boom, 11...Boom main body, 12...Mounting piece, 14...Trolley, 15...Traversing endless machine, 16...Traversing cable, 17...Hanging pulley block, 18...Hanging rope, 19... ...Hoisting machine, 22...
... Support plate, 23 ... Trunnion, 24 ... Mounting piece, 25 ... Drive cylinder, 25' ... Piston rod (operating rod), 30 ... Buffer means.

Claims (1)

[Claims] 1. A main frame with an open front side is installed at the upper center of the turning table on a turning table attached to a frame body equipped with a climbing mechanism at the top of the mast, and a trolley is attached to the top of the main frame. A boom equipped with a rail is pivotally supported at its core,
The boom is connected to the main frame and both sides at an appropriate dimension forward position from the pivot part so that it can be raised or lowered freely by a pair of linear actuators for hoisting, so that the actuator rods are kept horizontal when they are laid down during retreat; A trolley with a hanging pulley with a hook suspended along the underside of the boom that can be operated freely by a winch on a turning platform,
A crane for both horizontal and vertical lifting, characterized in that the boom is fixed by a locking device attached to the tip of the boom only when the boom is raised and lowered, and a buffer means for raising the boom is provided at a position behind the main frame.