JPH0732550Y2 - Jib drive controller - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) This invention is a self-propelled crane in which a telescopic boom is mounted on a swivel base mounted on a vehicle so that the telescopic boom can be hoisted and driven. The present invention relates to a drive control device for an extendable and retractable jib attached to a.

(Prior Art) A jib which is attached to the tip of a telescopic boom of a self-propelled crane so as to be able to move up and down is used to increase the working head and working radius of the self-propelled crane. As shown in FIGS. 1 and 2, this type of jib B is a tip end of the telescopic boom A of a self-propelled crane A in which a telescopic boom 3 is attached to a swivel base 2 arranged on a vehicle 1 so as to be capable of driving up and down. The outer jib section on the most proximal end side is composed of an outer shib section 4 on the proximal end side and an inner jib section 5 on the distal end side that is telescopically inserted into the outer jib section 4. The jib main body 6 is formed by pivotally connecting the base end portion of 4 to the lower end of the end of the telescopic boom 3 (or the lower part of the jib mounting base 6'attached to the end of the telescopic boom 3 ... Fig. 2). And the rear side of the outermost jib section 4 on the jib body 6 and the telescopic boom 3
A double-acting undulating cylinder 7 which is interposed between the upper ends of the ends (or the upper part of the mounting base 6 '... Fig. 2) to elevate and lower the jib body 6 and the outer jib of the jib body 6. A double-acting telescopic cylinder 8 is interposed between the section 4 and the inner jib section 5 and extends and moves the jib body 6 by its extension movement.

The undulating cylinder 7 is arranged so as to elevate the jib body 6 by the contraction movement so that the moment in the undulating direction acting on the jib body 6 is retained by the pulling force of the undulating cylinder 7. This is to prevent buckling force from acting on.

This type of jib includes an undulating cylinder 7 and a telescopic cylinder 8.
A jib drive control device is provided for undulating and expanding and contracting the jib 6 by controlling supply and discharge of hydraulic oil to and from the jib.

As shown in FIG. 3, a conventional drive control device for a jib has four jib raising and lowering operations which are respectively operated by operating levers 9a and 10a which are tiltably arranged in the operator's cab 2a on a swivel base 2 in the front-rear direction. A four-way three-position hydraulic switching valve 9 and a four-way three-position hydraulic switching valve 10 for expanding and contracting the jib are provided, and the four-way three-position hydraulic switching valve 9 and the undulating cylinder 7 are connected to two hydraulic hoses 9b and 9c.
Connected with four-way three-position hydraulic switching valve 10 and telescopic cylinder 8
Are connected by two hydraulic hoses 10b and 10c.
The relationship between the tilting operation direction of the operation levers 9a and 10a and the driving direction of the jib 6 is that the operation lever 9 is tilted forward (or backward).
When operated, the hoisting cylinder 7 extends (or contracts) and the jib 6 tilts (or hoists), and when the operating lever 10 is tilted forward (or tilted), the telescopic cylinder 8 extends (or contracts).
It is configured such that the jib 6 is moved to expand (or contract). Although such a configuration matches the operation feeling of the crane operator and has the effect that an erroneous operation is unlikely to occur, it corresponds to each of the undulating cylinder 7 and the telescopic cylinder 8 and has a four-way three-position hydraulic switching valve and two However, there is a drawback in that the hydraulic hose must be provided, which is complicated and expensive. In particular, the hydraulic hoses 9b, 9c, 10b, 10c are hose winders (not shown) so as to follow the telescopic movement of the telescopic boom 3.
Since it must be wound in a retractable manner, the above-mentioned configuration of the prior art, which requires the provision of four hydraulic hoses for convenience, causes the above drawbacks to be large.

The present invention includes a four-way three-position switching valve, two hydraulic hoses, and a valve device provided on the jib side and electrically remotely operated from the operator's cab 2a. (EN) A drive control device for a jib, in which the tilting direction of the operating lever of the four-way three-position hydraulic switching valve and the undulation and extension / contraction motion of the jib are similar to those of the drive control device for a conventional jib. It is what

(Means for Solving Problems) The jib drive control device of the present invention is configured as follows in order to achieve the above object.

A self-propelled crane operated by an operating lever that is tiltably arranged in the front-rear direction in the cab 2a on the swivel base 2 to control the connection between the pair of control ports and the pump oil passage and the tank oil passage. A four-way / three-position hydraulic switching valve is provided, and oil passages are individually connected to the jib body 6 or the jib body mounting base 6 ', respectively, to the extension and extension cylinders 8 and the expansion / contraction cylinder 8 when they are extended and when they are contracted. And a valve device connected to a pair of control ports of the four-way three-position hydraulic switching valve via two expandable and retractable hydraulic hoses, and the valve device is an operation switch provided in the operator's cab. One of the two hydraulic hoses and the undulating cylinder 7 is operated remotely.
And a switching state in which the other hydraulic hose is connected to the other side of the hydraulic hose and the undulating cylinder 7 is connected to the extending side of the hydraulic cylinder, and the same side of the one of the two hydraulic hoses and the contracting type of the expansion cylinder 8 are connected to each other. Is connected to the other side of the hydraulic hose and a switching state in which the expansion cylinder 8 is connected to the oil supply chamber when the expansion cylinder 8 is extended.

(Operation) According to the above configuration, the driving direction of the undulating cylinder and the telescopic cylinder is determined by the single four-direction three-position hydraulic switching valve, and the undulating cylinder and the telescopic cylinder are selectively selected by the valve device. Two hydraulic hoses are sufficient as the expandable and contractible hydraulic hoses, and it is possible to provide a jib drive control device with a simple structure and low cost.

Further, since the jib can be laid down or extended when the operation lever is tilted forward and the jib can be raised or contracted when tilted backward, it matches the operation feeling of the operator and is less likely to cause an erroneous operation. It also has advantages.

(Embodiment) Next, an embodiment of the drive control device for the jib of the present invention will be described with reference to FIG. The drive control device of the jib of the present invention is different from the drive control device of the conventional jib described above in comparison with the undulating cylinder 7.
Since only the hydraulic control device portion of the telescopic cylinder 8 is different, that of the above-mentioned prior art is applied to the description of other configurations and operations.

In FIG. 4, reference numeral 11 is operated by an operation lever 11a that is tiltably arranged in the operator's cab 2a in the front-rear direction, and controls the connection between the pair of control ports and the pump oil passage 12 and the tank oil passage 13. It is one four-way three-position hydraulic switching valve. Reference numeral 14 denotes a valve device provided at a proper position on the outermost jib section 4 on the most proximal end side of the jib body 6. The valve device 14 is connected to a pair of control ports of the four-way three-position hydraulic switching valve 11 via two telescopic hydraulic hoses 11b and 11c, and each extension of the undulating cylinder 7 and the telescopic cylinder 8 is extended. Oil passages are individually connected to the hour oil supply chamber and each of the reduced time oil supply chambers by pipes 7a, 7b, 8a, 8b. In this embodiment, the valve device 14
Is composed of two electromagnetic oil passage switching valves 14a and 14b. The oil passage switching valve 14a has a solenoid 14a '.
The hydraulic hose 11b is connected to the pipe 7a connected to the oil supply chamber when the undulating cylinder 7 is extended when the power is not supplied to the solenoid.
When energizing 14a ', connect the hydraulic hose 11b to the telescopic cylinder 8
It is configured to be connected to the oil passage 8a connected to the oil supply chamber during extension. Further, the oil passage switching valve 14b has its solenoid 14b '
The hydraulic hose 11c is connected to the oil passage 7b which is connected to the oil supply chamber when the undulating cylinder 7 is contracted when the power is not supplied to the solenoid.
When power is supplied to 14b ', hydraulic hose 11c is connected to telescopic cylinder 8
It is configured to be connected to the oil passage 8b that is connected to the oil supply chamber during reduction. Then, the solenoid 14 of each oil passage switching valve 14a, 14b
The a'and 14b 'are energized and de-energized by connecting and disconnecting an operation switch 15 provided in the operator's cab 2a of the swivel base 2. Operation switch 15 and solenoids 14a ', 14b'
The connection between them is made via a flexible wire (a conductive cable which is wound around the cord winder so that it can be rolled freely) so as to follow the expansion and contraction of the telescopic boom 3.

The four-way three-position hydraulic switching valve 11 connects the pump oil passage 12 to the hydraulic hose 11b and the tank oil passage 13 to the hydraulic hose 11c by operating the operation lever 11a forward.
By tilting the operation lever 11a backward, the pump oil passage 12 is connected to the hydraulic hose 11c and the tank oil passage 13 is connected to the hydraulic hose 11b.

When the operation lever 11a is tilted forward in the state shown in FIG. 4, that is, in the state where the operation switch 15 is turned off, the hoisting cylinder 7 extends and the jib B falls down. Further, when the operating lever 11a is tilted backward, the hoisting cylinder 7 is contracted and the jib B is hoisted.

When the operation lever 15a is tilted forward with the operation switch 15 in the contact state, the telescopic cylinder 8 extends and the jib B extends. When the operation lever 11a is tilted backward, the telescopic cylinder 8 contracts and the jib B contracts.

That is, the tilting operation direction of the operation lever 11a, the hoisting movement direction and the extension / contraction movement direction of the jib B match those of the telescopic boom 3 of the self-propelled crane.

Although the valve device 14 is attached to the outer jib section 4 of the jib body 6 in the above embodiment, the jib body 6 is attached to the tip of the telescopic boom 3 via the jib attachment base 6 '(Fig. 2). Of course, the valve device 14 may be mounted on the jib mounting base 6 '.

(Effect) The drive control device for a jib of the present invention configured and operated as described above is a valve device in which hydraulic oil from a single four-way three-position hydraulic switching valve is attached to the jib B via two hydraulic hoses. The two hydraulic hoses are selectively connected to the undulating cylinder and the telescopic cylinder by the valve device.Therefore, the number of four-way three-position hydraulic switching valves and hydraulic hoses is Since it can be halved, the structure can be made simple and inexpensive, but the tilting direction of the operating lever for operating the four-way three-position hydraulic switching valve and the hoisting and expanding and contracting movements of the jib are the same as those of the conventional one. Since they can be configured to be the same, there is an effect that an erroneous operation is hard to occur.

[Brief description of drawings]

FIG. 1 is an explanatory view of a self-propelled crane equipped with a jib. FIG. 2 is an explanatory view of a jib in which the method of attaching the jib to the tip portion of the telescopic boom is different from that of FIG. 1, FIG. 3 is an explanatory view of a conventional jib drive control device, and FIG. FIG. 3 is an explanatory view of a jib drive control device of the present invention. 2a; operator's cab, 7; undulating cylinder, 8; telescopic cylinder, 11; four-way three-position hydraulic switching valve, 11a; operating lever, 11b, 11c; hydraulic hose, 14; valve device, 15; operating switch, B; jib

Claims (1)

[Scope of utility model registration request] 1. A drive control device for a jib which is freely extendable and retractable and is attached to the tip of the telescopic boom of a self-propelled crane in which a telescopic boom is attached to a swivel mounted on a vehicle so as to be up and down freely. There, the jib is composed of an outer jib section on the proximal end side and an inner jib section on the distal end side that is elastically fitted into the outer jib section. A jib body that is pivotally connected to the lower part of the end of the telescopic boom or the bottom of a jib mounting base attached to the end of the telescopic boom, and a back side of the outermost jib section on the most proximal end side of the jib body. A double-acting undulating cylinder that is interposed between the top of the tip of the telescopic boom or the top of the jib mounting base attached to the tip of the telescopic boom and raises and lowers the jib body by its contracting movement. And a double-acting telescopic cylinder that is interposed between the outer jib section and the inner jib section of the jib body and extends the jib body by its extension movement. A four-way three-position hydraulic switching valve for controlling the connection between the pair of control ports and the pump oil passage and the tank oil passage, which is operated by an operation lever that is tiltable in the front-rear direction in the room, is provided, and the jib The four directions are connected to the body or the jib mounting base by oil passages individually connected to the extension refueling chamber and the extension refueling chamber and the contraction refueling chamber respectively, and through two extendable hydraulic hoses. A valve device connected to a pair of control ports of the three-position hydraulic switching valve is provided, and the valve device is remotely operated by an operation switch provided in the operator's cab. A switching state in which one of the two hydraulic hoses is connected to the oil supply chamber when the undulation cylinder is contracted and the other of the hydraulic hoses and the oil supply chamber when the undulation cylinder is extended are connected, and the same side as the one of the two hydraulic hoses. And a retractable cylinder refueling chamber is connected, and a switching state in which the same side of the hydraulic hose as the other side and an extendable cylinder refueling chamber are connected can be switched. Control device.