JPH10236777A - Jack automatic housing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a vehicle body from recklessly running away on a slope by operating a selective switch so as to house jacks in rear of the vehicle body, and then operating to house jacks in front of the vehicle body, at providing a working vehicle on the slope, when total four jacks provided in front and rear of the right and left both side of the vehicle body are housed. SOLUTION: When jacks are automatically housed at grounding an altitude working vehicle on a slope, an operator selects a selective switch 3 for housing in order of rear and front, and operates a jack automatic housing switch 2. Then a controller 5 sends control signals to hydraulic valves 6 by the signals from the respective switches 3, 2, and the hydraulic valves 6 feed hydraulic oil to jack cylinders 23 in rear of a vehicle body so as to house the respective jacks in rear of the vehicle body. Next when the respective jacks in rear of the vehicle body is detected to be perfectly housed by a housing detector 10, feed of hydraulic oil to the jack cylinders 23 in rear of the vehicle body is stopped, and hydraulic oil is fed to the jack cylinders 23 in front of the vehicle body so as to house the respective jacks in front of the vehicle body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jack automatic storage device provided in a work vehicle having a jack, such as an aerial work vehicle or a crane truck.

[0002]

2. Description of the Related Art The body of a working vehicle such as an aerial working vehicle or a crane vehicle is provided with wheels on the front and rear sides of the vehicle body for movement, and the lower end is grounded to ground. A total of four jacks supporting the
Books are provided. With this jack, the stability of the vehicle body is increased by supporting the vehicle body, and the boom can be safely operated to perform work at a high place and work of lifting heavy objects. By the way, when these jacks are stored from an overhanging state, there is also provided a jack automatic storage device that automatically stores and operates four jacks with a single operation.

[0003]

However, when the work vehicle is grounded on a slope where the road surface has a large inclination angle, the braking force of the parking brake of the vehicle normally acts only on the rear wheels. If the front wheels touch the ground before the rear wheels touch the ground when the jacks are automatically retracted, there is a risk that the work vehicle may run away below the slope while dragging the rear jack.

The present invention has been made in view of such a problem, and an object of the present invention is to provide an automatic storage device of a jack that can safely operate without a runaway of a work vehicle even on a slope.

[0005]

In order to achieve the above object, according to the present invention, a jack automatic storage switch for automatically storing each jack and an automatic storage switch for simultaneously storing all jacks are simultaneously operated. A selection switch for selecting one of simultaneous storage for storing operation, and front and rear sequential storage for storing jacks located on the left and right in front of the vehicle body after storing jacks located on the left and right behind the body first,
It is characterized by comprising a control means for controlling the operation of each jack by a signal from the jack automatic storage switch and a selection switch. Further, a grounding detector for detecting that the rear wheel of the vehicle body has touched the ground is provided, and the control device selects the front and rear operation sequentially by the selection switch, and when the jack automatic storage switch is operated, the rear of the vehicle body is When the jacks located on the left and right of the vehicle are retracted, and when the rear wheel is detected to be in contact with the ground by the signal from the grounding detector, the operation of each jack is also performed so that the jacks located on the left and right in front of the vehicle body are also retracted. It is more desirable to control. In addition, instead of the selection switch, an inclination angle detector for detecting an inclination angle of a road surface on which the vehicle body is grounded is provided, and when the inclination angle of the road surface is equal to or less than a predetermined value, the control device simultaneously retracts all jacks. With simultaneous storage, when the inclination angle of the road surface exceeds a predetermined value, the jacks located on the left and right behind the vehicle body are stored first, and then the jacks located on the left and right in front of the vehicle body are stored. It is also more desirable to control the operation of each jack.

[0006]

In a work vehicle equipped with such a jack automatic storage device, a total of four jacks are provided before and after the left and right sides of the vehicle body. When the vehicle is grounded on a flat ground with few corners, simultaneous storage is selected, and when the work vehicle is grounded on an inclined ground, the front and rear storage is selected by a selection switch. In this case, four jacks are stored at the same time, and on a slope, the rear jack of the vehicle body is stored first, and then the front jack of the vehicle body is stored. As a result, the outrigger can be stored in a short time on flat ground, and the jack can be automatically stored safely on a sloped ground without the body blasting. Further, a rear tire grounding detector is provided in the jack automatic storage device, and the control device first stores the jack behind the vehicle body on a slope, and after the rear tire is grounded, the jack in front of the vehicle body also performs the storing operation, It is possible to shorten the operation time for storing the jack while maintaining the safety of the automatic storage of the jack on the slope. Further, by providing an inclination angle detector instead of the selection switch, when the inclination angle of the road surface is equal to or less than a predetermined value by the signal from the inclination angle detector, the control device simultaneously stores all the jacks and operates the road surface. If the inclination angle of the jack exceeds the predetermined value, the jack at the rear of the car body is operated to retract first, and then the jack at the front of the car body is operated to be retracted. Runaway of the vehicle body due to incorrect selection can be prevented, and safety can be further increased.

[0007]

Preferred embodiments of the present invention will be described below with reference to the drawings. First, FIG. 4 shows an aerial work vehicle equipped with the automatic jack storage device according to the present invention.
The aerial work vehicle 40 is configured with a truck as a base body, and a turntable 42 that can freely turn horizontally with respect to the body 41 is attached to a rear portion of the body 41. A boom 43 configured to be telescopically extendable and retractable is attached to the upper portion of the swivel base 42 so as to be able to move up and down. Further, a worktable 44 is attached to a tip of the boom 43. The work table 44 is held horizontally by a leveling device (not shown) regardless of the up-and-down state of the boom 43.

According to the aerial work vehicle 40 constructed as described above, an operator (not shown) riding on the work table 44 can move the work table 44 to an arbitrary height through the respective operations of the swivel table 42 and the boom 43. Can be moved to places. Then, electric work can be performed on the upper part of the power pole, or construction work of a building can be performed.

By the operation of the swivel table 42 and the boom 43, a moment acts on the vehicle body 41 in a direction in which the vehicle body 41 is overturned. In order to stabilize the vehicle body 41 against such a falling moment, the outriggers 20 are attached at four positions on the front, rear, left and right of the vehicle body 41. The outrigger 20 includes an outrigger beam 22 and a jack 30 that extend (extend) and contract (retract) toward the side of the vehicle body 41 by the expansion and contraction operation of a hydraulic extension cylinder 21 attached to the vehicle body 41. 31. Further, the jacks 30 and 31 are connected to the outrigger beam 2.
2, an outer post 23 attached to the tip of the outer post 23 so as to extend vertically, an inner post 24 inserted into the outer post 23 so as to be able to expand and contract downward, and an inner post 24 attached to the outer post 23 and the inner post 24. And a grounding plate 26 attached to the lower end of the inner post 24.

The outrigger 20 configured as described above is
After appropriately extending the outrigger beam 22, the jack 3
The vehicle body 41 can be supported on the ground by extending (lowering) the inner posts 24 of the 0 and 31 to ground the ground plate 26 to the ground. And each jack 3
In order to control the storage operation of the inner post 24 at 0 and 31 collectively, the automatic jack storage device 1 according to the present invention is attached to the aerial work vehicle 40. Hereinafter, the jack automatic storage device 1 will be described with reference to FIGS. 1 and 2.

The automatic jack storage device 1 comprises a jack automatic storage switch 2, a selection switch 3, and a control means 4. When the operator operates the jack automatic storage switch 2, the control means 4 controls the jack 30,
A signal for performing the automatic storage operation of the automatic transmission 31 is transmitted. The selection switch 3 allows an operator to select either simultaneous storage or sequential storage before and after the automatic storage operation of the jacks 30 and 31. This simultaneous storage means that the four jacks 30 and 31 on the left and right sides of the
Are stored at the same time, and the sequential storing is performed by storing the two jacks 31 behind the vehicle body 41 and completely storing the jacks 30, 31.
Alternatively, the two jacks 30 located in front of the vehicle body 41 are stored after the rear wheel 28 of the vehicle body 41 is grounded. The storage detector 10 for detecting that the jacks 30 and 31 are completely retracted includes a limit switch for detecting that the inner post 24 or the ground plate 26 is located at the retracted position, or a retractable operation of the inner post 24. It is constituted by a pressure switch for detecting that the pressure of the oil chamber on the rod side (reduction side) of the hydraulic jack cylinder 25 to be operated becomes equal to or higher than a predetermined pressure. In addition, the ground contact detector 7 that detects that the rear wheel 28 of the vehicle body 41 is in contact with the ground, detects that the amount of deflection of the leaf spring supporting the rear wheel 28 of the vehicle body 41 or the amount of movement of the axle with respect to the vehicle body 41 is equal to or less than a predetermined amount. And a limit switch for detecting that

On the other hand, the control means 4 comprises a controller 5 and a hydraulic valve 6, and the controller 5
When receiving signals from the jack automatic storage switch 2 and the selection switch 3, the hydraulic valves 6 are configured to store the jacks 30 and 31 in the storage method selected by the selection switch 3, either simultaneous storage or sequential storage before and after. To the control signal. The hydraulic valve 6 is actuated by a control signal sent from the controller 5 to control the supply and discharge of hydraulic oil from the hydraulic pump 9 provided on the vehicle body 41 to the reduction-side oil chamber of the jack cylinder 25 of each jack 30, 31. Controls the reduction operation of the jacks 30 and 31 according to the control signal from the controller 5.
The automatic storage operation of 0 and 31 is performed.

[0013] Here, the operator actually operates the jacks 30, 3
The case where the automatic storage operation of 1 is performed will be described. When the aerial work platform 40 is grounded on a flat place, the jack 30,
In the case of automatically storing 31, the operator selects the selection switch 3 for simultaneous storage and operates the jack automatic storage switch 2. The controller 5 uses the signal from the selection switch 3 and the signal from the jack automatic storage switch 2 to simultaneously store the jacks 30, 31 so that the hydraulic valves 6
To the hydraulic valve 6 by the control signal.
Supplies hydraulic fluid from the hydraulic pump 9 to each jack cylinder 2
By simultaneously supplying the jacks 30 and 31 to the reduction side oil chamber 5, the jacks 30 and 31 are simultaneously stored.

In the case where the automatic storage is performed when the aerial work vehicle 40 is in contact with the sloped ground, the operator selects the selection switch 3 to be stored sequentially and operates the jack automatic storage switch 2. The controller 5 controls the hydraulic valve 6 to sequentially store the jacks 30 and 31 in accordance with the signal from the selection switch 3 and the signal from the jack automatic storage switch 2.
To the hydraulic valve 6 by the control signal.
First, the hydraulic oil from the hydraulic pump 9 is supplied to the reduction-side oil chambers of the jack cylinders 25 of the two jacks 31 behind the vehicle body 41 to store the respective jacks 31 behind the vehicle body. Next, when the storage detector 10 detects that the jacks 30 and 31 are completely stored, the controller 5
Controls the hydraulic valve 6 to stop the supply of hydraulic oil to the jack cylinders 25 of the jacks 31 at the rear of the vehicle body, and from the hydraulic pump 9 to the reduction-side oil chambers of the jack cylinders 25 of the two jacks 30 at the front of the vehicle body. And the jacks 30 at the front of the vehicle body are stored.

[0015] This allows the jacks 30, 31 on the sloped land.
When automatically retracting the rear wheel 28
, The parking brake (not shown) for applying a braking force to the rear wheel 28 can prevent the danger of the aerial work vehicle 40 running away downward on the slope.

In addition, when the controller 5 sequentially stores the front and rear, if the rear wheel 28 touches down before completely storing the jack 31 at the rear of the vehicle body, the jack 30 at the front of the vehicle body may be stored together. . In this case, when the operator selects the selection switch 3 to be sequentially stored in front and rear and operates the jack automatic storage switch 2, the controller 5 uses the signal from the selection switch 3 and the signal from the jack automatic storage switch 2 to control each jack. A control signal is sent to the hydraulic valve 6 so that the hydraulic valves 30 and 31 are sequentially stored. According to the control signal, the hydraulic valve 6 first sends hydraulic pressure to the reduction-side oil chambers of the jack cylinders 25 of the two jacks 31 behind the vehicle body 41. Hydraulic oil is supplied from the pump 9 to store the jacks 31 at the rear of the vehicle body. Next, when the grounding detector 7 detects that the rear wheel 28 of the vehicle body 41 has been grounded, the controller 5 controls the hydraulic valve 6 to reduce the oil chambers of the jack cylinders 25 of the two jacks 30 located in front of the vehicle body. Hydraulic oil is supplied from the hydraulic pump 9 to store the jack 30 at the front of the vehicle body and the jack 31 at the rear of the vehicle together. Accordingly, it is not necessary to stop the storing operation of the jack 30 at the front of the vehicle body until all the jacks 31 at the rear of the vehicle body are stored. As a result, storage time can be reduced.

Further, as shown in FIG. 3, a road surface inclination angle detector 8 may be provided in place of the selection switch 3 of the jack automatic storage device 1. This road surface inclination angle detector 8
Is provided in the vehicle body 41 with an inclination angle sensor for detecting that the inclination angle is equal to or larger than a predetermined inclination angle, and before the jacks 30 and 31 are extended, the controller 5 stores whether the vehicle body 41 is equal to or larger than the predetermined inclination angle. The controller 5 calculates whether the difference between the extension amounts of the front and rear jacks 30, 31 is equal to or greater than a predetermined value by an extension sensor that detects the extension amount of the front and rear jacks 30, 31 of the vehicle body 41. It is constituted so that. In this case, when the inclination angle detector 8 detects that the inclination angle is equal to or more than the predetermined angle, the controller 5 automatically selects the front and rear sequential storage, and when the inclination angle is equal to or less than the predetermined angle, the simultaneous storage. The controller 5 sends a control signal to the hydraulic valve 6 in response to a signal from the jack automatic storage switch 2 in the same manner as in the automatic jack storage device 1 to perform a simultaneous storage operation or a sequential storage operation.
This eliminates the need for the operator to make a selection by the selection switch 3 due to the inclination of the road surface. This facilitates the work and also prevents an accident caused by selecting the selection switch 3 by mistake.

[0018]

As described above, the automatic jack storage device of the present invention not only facilitates the storage operation of the jack, but also allows the vehicle to move downward on the slope in the automatic storage operation of the jack on the slope. The risk of runaway can be prevented, and a safer jack automatic storage device can be obtained. Further, by providing the rear-wheel grounding detector, the storage operation time can be shortened, and the workability can be improved. Further, by providing a road surface inclination angle detector in place of the selection switch, the trouble of selecting the switch can be omitted, and an accident caused by the operator erroneously selecting the selection switch can be reliably prevented.

[0019]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an automatic jack storage device according to the present invention.

FIG. 2 is a configuration diagram in which a grounding detector is added to the automatic storage device.

FIG. 3 shows an alternative to the selection switch of the automatic storage device,
It is a block diagram to which the inclination angle detector was added.

FIG. 4 is a perspective view of an aerial work vehicle provided with the automatic storage device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Jack automatic storage device 2 Jack automatic storage switch 3 Selection switch 4 Control means 5 Controller 6 Hydraulic valve 7 Grounding detector 8 Tilt angle detector 10 Storage detector 28 Rear wheel 30 Jack in front of vehicle body 31 Jack in rear of vehicle body 41 Vehicle body

Claims (3)

[Claims] 1. A jack automatic storage device provided with front and rear left and right sides of a vehicle body for stably supporting a vehicle body by projecting downward to ground a lower end portion thereof, wherein each jack is automatically stored. A jack automatic storage switch that performs automatic storage operation, a simultaneous storage operation that simultaneously stores all jacks for automatic jack storage operation, and a front left and right front of the vehicle And a control means for controlling the operation of each jack by a signal from the jack automatic storage switch and the selection switch. Jack automatic storage device. 2. A grounding detector for detecting that the rear wheel of the vehicle body has touched the ground, wherein the control device selects the front and rear sequential operation by the selection switch and operates the jack automatic storage switch. The jacks located on the left and right behind the vehicle body are retracted, and when signals from the grounding detector detect that the rear wheels have contacted the ground, the jacks located on the left and right in front of the vehicle body are also retracted. The automatic jack storage device according to claim 1, wherein 3. A jack automatic storage device provided with front and rear left and right sides of a vehicle body for stably supporting a vehicle body by projecting downward to ground a lower end thereof, wherein each jack is automatically stored. A jack automatic storage switch for performing an automatic storage operation, an inclination angle detector for detecting an inclination angle of a road surface that grounds a vehicle body, and a road surface inclination angle determined by a signal from the jack automatic storage switch and the inclination angle detector. When the value is equal to or less than the value, all jacks are stored at the same time, and when the inclination angle of the road surface exceeds a predetermined value, the jacks located at the left and right behind the vehicle body are stored first, and then the jacks are located at the left and right in front of the vehicle body. A jack automatic storage device comprising: control means for controlling the operation of each jack so as to store the jack.