JP2540638Y2 - Jack interlock device for work vehicle with boom - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jack interlock device for a working vehicle having a boom.

[0002]

BACKGROUND OF THE INVENTION work vehicle of di conventional having this kind of boom
The jack interlock device will be described below using the aerial work vehicle A shown in FIG. 2 as an example. In FIG. 2 , the aerial work vehicle A is provided with a swivel base 2 rotatable on a vehicle 1, and a base cylinder is pivotally supported by the swivel base 2 and an up-and-down cylinder 3 disposed between the appropriate place and the swivel base 2 The telescopic boom 4 is provided so that it can be raised and lowered. The telescopic boom 4 includes a base boom 5, an intermediate boom 6, and a leading boom 7. The intermediate boom 6 is inserted into the base boom 5 and the leading boom 7 is inserted into the intermediate boom 6 so as to be able to extend and contract sequentially. A telescopic drive is provided. At the end of the telescopic boom 4, a bucket 8 for an operator
And the telescopic boom 4 is appropriately extended and retracted, raised and lowered, and the revolving base 2 is swiveled, so that the worker riding on the bucket 8 can be positioned at an appropriate position in a high place and work at a high place can be performed. It has become.

[0003] The vehicle 1 of such an aerial work vehicle A includes:
A pair of left and right jacks 9, 9 are provided in front and behind the vehicle 1, and
The jack 9 carries the vehicle 1.
That is, the jack 9 stably supports the aerial work vehicle A with respect to the ground so that the aerial work vehicle A does not fall due to the boom state of the telescopic boom 4.

A boom support 10 is disposed on the vehicle 1 of the aerial work vehicle A. The boom support 10 is used to move the telescopic boom 4 when the aerial work vehicle A travels.
The telescopic boom 4 that has been completely reduced is pivoted on the swivel base 2 so as to be positioned immediately above the boom support 10, and the up-and-down cylinder 3 is driven to contract to move the telescopic boom 4 to the boom support. 10 and stored.

A boom placement / storage detection switch 11 is disposed on the boom support 10, and is activated when the telescopic boom 4 is placed and stored on the boom support 10. When this boom mounted storage detection switch 11 is not in operating state as the jack 9 can not be driven, thereby implicating driving circuit of the boom mounted storage detection switch 11 and the jack 9.

Namely, the at the time of travel and move the aerial A is is for storing the telescopic boom 4 and the jack 9 is in the working state, without the telescopic boom 4 in the storage state storing jack 9 stretch When the vehicle 1 falls over depending on the boom state of the boom 4 (for example, when the telescopic boom 4 is almost extended and the telescopic boom 4 is lying down, the swivel base 2 is turned to the side of the vehicle 1 to move the telescopic boom 4 to the side of the vehicle 1). When the vehicle is pointed, the stability of the aerial work vehicle A is poor, and if the vehicle 1 is not carried by the jack 9 at this time, the aerial work vehicle A will fall over.) As described above, the boom placement / storage detection switch 11 and the jack 9
Are related to each other.

Therefore, in the aerial work vehicle A configured as described above, the telescopic boom 4 is connected to the boom support 1.
Otherwise, the boom-placed storage detection switch 11 will not be activated and the jack 9 cannot be stored. When traveling and moving the aerial work vehicle A, the telescopic boom 4 in the working state is first placed on the boom support 10 and stored, and then the jack 9 is stored. A is prevented from overturning.

[0008]

However, the aerial work vehicle A provided with the boom placement / storage detection switch 11 has the following problems. That is, the boom placement / storage detection switch 11 does not operate unless the telescopic boom 4 is placed and stored on the boom support 10.
Due to a cause such as generation of rust due to dust and water entering the operating portion of the boom placement / storage detection switch 11, the telescopic boom 4 is activated even though it is not placed and stored on the boom support 10. Failure could occur.
In such a state, the jack 9 may be operated to invert the aerial work vehicle A even though the telescopic boom 4 is inadvertently erroneously operated and the telescopic boom 4 is not placed and stored on the boom support 10. .

An object of the present invention is to provide a jack interlock device for a work vehicle having a boom that solves such a problem.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, a jack interlock device for a working vehicle having a boom according to the present invention is provided with a boom for turning and raising and lowering on a vehicle, and a pair of left and right jacks is provided. A work vehicle such as a mobile crane or an aerial work vehicle, which is provided before and after the vehicle so as to carry the vehicle with the jack , particularly when the vehicle travels, the boom is placed and stored on a boom support provided on the vehicle. A work vehicle comprising: a boom undulation angle detector and a boom turning angle detector; and a boom state is determined by receiving a signal from each of the detectors. In a work vehicle provided with a safety device that gives an alarm when the vehicle becomes inoperable, the up-and-down angle detector detects that the boom has fallen below a predetermined level and the turning angle A boom storage state detection switch that operates when the boom is positioned near the position directly above the boom support by the output device, and a boom placement storage detection switch that detects that the boom has been placed and stored on the boom support And the jack can be driven only when the boom storage state detection switch and the boom placement storage detection switch operate.

[0011]

In the jack interlock device for a work vehicle having a boom according to the present invention configured as described above, the boom storage state detection switch does not operate even if the boom mounting / storage detection switch fails and remains activated. because are not intended to be the driving of the jack, it is always boom when driving the jack has become a storage state, by mistake despite not placing store the boom on the boom support di
Even if the jack is stored, the jack cannot be stored and the aerial work vehicle can be prevented from tipping over.

[0012]

[Example] jack of the work vehicle with a boom of following the present invention
The key interlock device will be described with reference to FIG . In describing the jack interlock device for a working vehicle having a boom according to the present invention, a case where the present invention is applied to an aerial work vehicle A shown in FIG. 2 and described in the related art will be described. Therefore, reference numerals 1 to 1 used in the prior art
1. In the following description, the same reference numeral A is used as the same, and the description is omitted using the same reference numeral.

In FIG . 1 , reference numeral 12 denotes a length detector of the telescopic boom 4, which is provided with a cord winder attached to the base boom 5, and the leading end of the cord delivered from the drum of the cord winder is the leading end of the boom. And the cord is fed out and in from the cord winder in conjunction with the telescopic movement of the telescopic boom 4, and the drum rotation of the cord winder is detected by a potentiometer.
The length of expansion and contraction is detected. Reference numeral 13 denotes a undulation angle detector of the telescopic boom 4, which has a weight therein and detects the angle of the telescopic boom 4 with respect to the weight by a potentiometer. 4 to detect the undulation angle. 14 is
A turning angle detector of the telescopic boom 4, which detects a turning angle of the turning base 2 with respect to the vehicle 1 (that is, a turning angle of the telescopic boom 4 with respect to the vehicle 1) by disposing a potentiometer between the vehicle 1 and the turning base 2. It is.

Reference numeral 15 denotes a safety device, which stores in advance an operable working range of the telescopic boom 4 in all boom states, and receives a signal from each of the detectors to change the current boom state of the telescopic boom 4. A determining means for determining whether the work area is operable;
However, when it is determined that the current boom state of the telescopic boom 4 is not within the operable working range, the driving operation of the telescopic boom 4 in a direction deviating from the operable working range with the boom state is stopped. A stop signal is output to each of the operations. That is, the expansion / contraction driving means 1
7, a stop signal is appropriately output to each operation means of the up / down driving means 18 and the turning driving means 19. Such a safety device 15 is normally provided in a work vehicle such as a work aerial vehicle A.

Reference numeral 20 denotes a first arithmetic unit provided in the safety device 15, which receives a signal from the length detector 12 and determines that the telescopic boom 4 is in a substantially fully contracted state. At this time, a signal is output. 2
Reference numeral 1 denotes a second calculating means provided in the safety device 15, which receives a signal from the undulation angle detector 13 and sets the telescopic boom 4 at a predetermined angle or less (here, the telescopic boom 4).
Is determined to be almost the same angle as when the camera is mounted on the boom support 10), and a signal is output at this time. Reference numeral 22 denotes a third calculating means provided in the safety device 15, which receives a signal from the turning angle detector 14 and causes the telescopic boom 4 to move the boom support 1
It is determined that it is located near the position immediately above 0, and a signal is output at this time.

Reference numeral 23 denotes a fourth arithmetic unit provided in the safety device 15, and outputs a signal only when receiving a signal from each of the first, second, and third arithmetic units 20, 21, and 22. Then, the relay 24 is operated. Numeral 25 is a relay contact of the relay 24, which is a normally open contact that closes the circuit when the relay 24 operates. The relay contact 25 is normally open when the first, second, and third arithmetic means 20, 21, and 22 output signals (ie, when the telescopic boom 4 is almost in the retracted state). It is a contact point and corresponds to the boom storage state detection switch described in the claims for utility model registration.

Reference numeral 26 denotes a relay that is activated when the relay contact switch 25 and the boom placement / storage detection switch 11 are activated. At that time, the relay contact 27 is closed. Reference numeral 28 denotes a jack operation valve, and by operating this valve, the hydraulic pressure from the hydraulic pump 29 is changed to each jack.
The jacks 9 are supplied to drive the jacks 9. Reference numeral 30 denotes an electromagnetic valve, which is
It is interposed between the oil passage leading to the jack operation valve 28 and the tank,
When energized, the oil passage is closed, and when not energized, the oil passage is opened.

The jack interlock device of the work vehicle having the boom according to the present invention configured as described above operates as follows. Now, it is assumed that the boom placement / storage detection switch 11 has failed and remains operating.
Then, the telescopic boom 4 is almost extended, and the swivel 2
Is turned to the side of the vehicle 1 to direct the telescopic boom 4 to the side of the vehicle 1 (the stability of the aerial work vehicle A is poor,
At this time, if the vehicle 1 is not carried by the jack 9,
It is assumed that the jack work valve 28 is inadvertently operated to reduce the jack 9 when the aerial work vehicle A falls over).
However, since the telescopic boom 4 is not substantially in the retracted state, the first, second, and third arithmetic means 20, 21, 2,
2 does not output a signal. Therefore, no signal is output from the fourth calculation means, so that the relay 24 does not operate, and the relay contact 25 (boom storage state detection switch) does not operate. Then, the relay 26 does not operate, and the solenoid valve 30 opens the oil passage and the pressure oil from the hydraulic pump 29 returns to the tank.
It is not supplied to the jack operation valve 28, and the storing operation of each jack 9 is prevented.

At this time, when the telescopic boom 4 is substantially fully contracted, the swivel base 2 is turned so that the telescopic boom 4 is located near the position directly above the boom support 10, and the telescopic boom 4 is placed on the boom support 10. When the robot is brought to the lying state to an angle substantially close to the above angle, a signal is output from each of the first, second, and third arithmetic means 20, 21, and 22. Therefore the fourth
A signal is also output from the calculating means, and the relay 24 operates,
The relay contact 25 (boom storage state detection switch) operates. Then, the relay 26 is operated, the solenoid valve 30 closes the oil passage, and the hydraulic pressure from the hydraulic pump 29 is applied to the jack operated valve 2.
The storage operation of each jack 9 is performed.

[0020] Also it remains as the operating state boom mounted storage detection switch 11 thus has failed, the relay contacts 25 (boom storage state detection switch) is not working di
The jack 9 cannot be driven. When the jack is to be driven, the telescopic boom 4 must be almost in the retracted state.
In case of failure, even if the jack is erroneously stored and operated, the aerial work vehicle A does not fall.

From the above description, if the only purpose is to prevent the aerial work vehicle A from tipping over even if the jack is erroneously stored, the boom-mounted storage detection switch 1 is used.
1 is not necessary, and the operation of the jack 9 may be interlocked only by the boom storage state detection switch (relay contact 25). However, the boom placement / storage detection switch 11 is a switch that not only detects that the telescopic boom 4 has been stored, but also detects that the telescopic boom 4 has been placed on the boom support 10. That is, placing the telescopic boom 4 on the boom support 10 mechanically prevents the swiveling movement of the telescopic boom 4 and the tilting movement of the telescopic boom 4, and the telescopic boom 4 moves when the aerial work vehicle A travels. Swing can be reliably prevented. Thus the operation of the boom mounted storage detection switch 11 and the jack
Relating the storage operation of the key 9 also has the purpose of setting the traveling state of the aerial work vehicle A to the above-described state and ensuring safety during traveling, and thus also involves the boom placement / storage detection switch 11. Things.

[0022] In the above embodiment has been described as a work vehicle having a telescopic boom, having a inelastic boom
The same can be applied to a working vehicle. That is, the fourth
The calculating means 23 includes a second calculating means 21 and a third calculating means 22
A signal may be output when an output signal is received.

In the above embodiment, the work vehicle having a boom is described as an aerial work vehicle. However, the present invention can be applied to a work vehicle such as a mobile crane. The safety device used for the mobile crane is slightly different from the safety device 15 described above (including a load detector acting on the telescopic boom, and a load and load acting on the telescopic boom stored in advance according to the boom state of the telescopic boom. The calculation is performed by comparing with the actual load detected by the detector.) It is needless to say that each of the above-described detectors is provided, and the above-described detectors can be used to perform the same operation.

[0024]

The jack interlock device for a working vehicle having a boom according to the present invention, which is constructed and operated as described above, can be used in a case where the boom placement / storage detection switch fails and remains in the operating state. also by operating the jack by mistake despite not placing stored on the support, Ja
Prevent operation of Tsu keys can be prevented to fall the work vehicle.

[Brief description of the drawings]

1 is an explanatory view for explaining a work vehicle jack Lee <br/> Ntarokku device having the present invention the boom.

FIG. 2 is an explanatory diagram illustrating a high-altitude work vehicle as a work vehicle having a boom.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 vehicle 4 boom (telescopic boom) 9 jack 10 boom support 11 boom placement and storage detection switch 13 undulation angle detector 14 turning angle detector 15 safety device 25 boom storage state detection switch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B66F 11/04 B66F 11/04

Claims (1)

(57) [Scope of request for utility model registration] With 1. A comprises turning on the vehicle and undulations freely boom work vehicle such as a mobile crane or aerial which is adapted to carry the vehicle by the jack comprises a pair of left and right jack before and after the vehicle In particular, a work vehicle configured to place and store the boom on a boom support provided on the vehicle during traveling and traveling thereof, wherein each detector includes a boom undulation angle detector and a boom turning angle detector. A work vehicle equipped with a safety device that receives a signal from each of the detectors, determines a boom state, and issues an alarm when the boom state becomes a state in which the work vehicle cannot be operated. Boom storage that is activated when it detects that the boom has fallen below a predetermined level and when the turning angle detector detects that the boom is located near the position directly above the boom support. A state detection switch and a boom placement / storage detection switch for detecting that the boom has been placed / stored on the boom support are arranged, and only when the boom storage state detection switch and the boom placement / storage detection switch are operated , the jack is turned off. A jack interlock device for a work vehicle having a boom, which is configured to be driven.