JPH0623490Y2 - Horizontal body installation device - Google Patents

Description

[Detailed Description of Device] a. Purpose of the Invention (Industrial field of application) The present invention controls an outrigger jack that is mounted on a work vehicle having a boom such as an aerial work vehicle or a crane vehicle for the purpose of ensuring stability during work. Performing apparatus for horizontally installing the vehicle body.

(Prior Art) As a jack used in such a work vehicle, there is, for example, one shown in FIG. In this structure, an outrigger box 71 is fixed to the body frame so as to extend laterally, and an outrigger beam 72 is telescopically fitted in the box 71. A jack 75 is attached to the tip of the beam 72 so as to extend substantially vertically. Has been. The jack 75 includes an outer post 76 fixed to the tip of the beam 72, an inner post 77 that is vertically inserted into the outer post 76, and a ground plate 78 joined to the lower end of the inner post 77. A jack cylinder 79 is provided inside the posts 76 and 77 to move the inner post 77 up and down. Note that the jack 75 may be directly attached to the vehicle body frame, and as the jack 75, the ground plate 78 is attached to the lower end of the jack cylinder 79.
There is also a case where a structure with just attached is used.

In a work vehicle equipped with such a jack 75,
During work, the jack cylinder is extended to ground the ground plate 78 to support the vehicle body in a substantially horizontal position. In this case, if the ground on which the work vehicle is located is horizontal, it suffices to extend the jack cylinder. However, when extending the jack cylinder on a sloping ground or uneven ground, the amount of extension is adjusted. Need to be horizontal. As a device for controlling the operation of the jack cylinder in such a case, for example, the one disclosed in Japanese Utility Model Publication No. 55-44687 is known.

Although the one disclosed in this publication has jack cylinders arranged at two positions on the left and right of the vehicle body, a type in which jack cylinders for outriggers are provided at four places on the vehicle body has been widely used. In this case, the inclination of the vehicle body is detected and the operation of each jack cylinder is controlled so that the vehicle body becomes horizontal.

When the boom of the work vehicle is operated, a moment corresponding to the load applied to the boom (including the boom's own weight) acts on the vehicle body, and when this moment becomes excessive,
The work vehicle may fall. To prevent this,
In general, such a work vehicle is equipped with a moment limiter. This moment limiter has been
In many cases, the load applied to the boom, the boom's total length and undulation angle, the outrigger overhang width, etc. are detected to calculate the moment, and the work allowable range for operating the boom is set. To obtain, a large number of detectors is needed.

(Problems to be solved by the invention) However, in the work vehicle as described above, recently,
Miniaturization is in progress, and miniaturization is required correspondingly to the above-mentioned vehicle body horizontal installation device and moment limiter. However, as described above, these devices require a large number of detectors, which makes it difficult to miniaturize them.

In view of the above problems, it is an object of the present invention to provide a vehicle body horizontal installation device that also serves as a moment limiter.

B. In order to solve the above-mentioned problems, the horizontal installation apparatus for a vehicle body according to the present invention uses a pressure detector and a tilt detector to detect each jack when the boom retracted detector detects the retracted state of the boom. It controls the jack cylinder by detecting the control hydraulic pressure of the cylinder and the inclination of the vehicle body, and operates so that the vehicle body is installed horizontally. When it is detected that the boom is operating, the fall prevention device operates based on the ground reaction force of the jack cylinder calculated from the control oil pressure of each jack cylinder detected by the pressure detector. The stable state of is determined.

(Operation) When starting the work, when the vehicle body is first installed horizontally, the present apparatus controls the expansion and contraction of the jack cylinder based on the signals from the pressure detector and the inclination detector to install the vehicle body horizontally. After that, when the boom is operated, it operates as a moment limiter that prevents the vehicle body from falling over based on the signal from the pressure detector. Therefore, it is possible to reduce the size and weight of the vehicle as compared with the conventional method of separately mounting the horizontal body installation device and the moment limiter.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

First, FIG. 2 shows a work vehicle 1 equipped with a horizontal body installation device according to the present invention. This work vehicle 1 has a swivel base 5 mounted on a vehicle body 2.
Is rotatably mounted, the swivel base 5 swivels by the operation of a swivel motor (not shown), and the boom 3 is mounted on the swivel base 5.
The base end of the boom 3 is pivotally supported, and the boom 3 is raised and lowered by the expansion and contraction of the hoisting cylinder 5 having both ends pivotally attached to the swivel 5 and the boom 3. is there. During work, the hoisting cylinder 54 is extended to erect the boom 3, the swing motor is rotated to swivel the swivel base 5 to swivel the boom 3, and the telescopic cylinder 64 is stretched to extend the boom 3. Then, the work bucket 4 is carried to a predetermined height, and the work on the work bucket 4 is performed by a worker who rides on the work bucket 4.

In order to firmly support the vehicle body during such work at high places, the outrigger jacks 11 and 1 are provided at four locations on the side of the vehicle body.
2, 13, 14 (however, 13, 14 are not shown because they are opposite sides of the vehicle body) are attached.

These jacks 11 to 14 are, like the conventional structure shown in FIG. 4, the tips of the outrigger beams 15b to 18b fitted in the outrigger boxes 15a to 18a fixed to the vehicle body frame etc. so as to be capable of expanding and contracting in the lateral direction. Attached to.

An apparatus (horizontal body horizontal installation apparatus) for controlling the operation of these four jacks 11 to 14 and the boom 3 is shown in FIG.

As shown in this figure, the jacks 11 to 14 include outer posts 11c to 14c fixed to the tips of the outrigger booms 15b to 18b, inner posts 11b to 14b extending and contracting downward with respect to these outer posts, and inner posts. Ground plates 11a to 14a attached to the lower end of the
And jack cylinders 11 arranged inside both posts
d to 14d. Each jack cylinder 11
d to 14d are connected to the hydraulic power source 5 through the hydraulic lines 21 to 24 and the hydraulic control valve 20, respectively, and the jack cylinders 11d to 14d are expanded and contracted by the operation of the control valve 20, and the expansion and contraction of the inner posts 11b to 14b are independent. And can be controlled.

The operation control of the hydraulic control valve 20 is performed by the control lines 41 to 4
4 based on the operation control signal sent from the controller 40. Therefore, this controller 40
Are attached to the vehicle body 2 and a vehicle body inclination signal sent from an inclination detector 8 for detecting the inclination of the vehicle body 2 via a signal line 8a and pressure sensors 31 to 31 for detecting the hydraulic pressures of the hydraulic pressure lines 21 to 24, respectively. 34 to the signal line 31a
The hydraulic pressure signal sent via .about.34a is input, and the storage signal sent from the boom storage detector 35 for detecting the storage state of the boom 3 via the signal line 35a is also input.

In addition, the hydraulic pressure of the hydraulic lines 21 to 24 is set to the ground plate 11
a~14a must support the ground reaction force acting on the jack 11 to 14 when the ground (force indicated by arrow _f 1 ~f _4), the controller 40 from the hydraulic pressure detected by the pressure sensor 31 to 34 The ground reaction force (f _{1 to} f ₄ ) is calculated in the fall prevention device included.

On the other hand, the undulation control of the operation control of the boom 3 is performed by the hydraulic power source 5
The pressure oil from 0 is sent to the first hydraulic chamber 54a of the hoisting cylinder 54 via the hydraulic line 51a by the manual valve 52 for selecting the hoisting of the boom to extend the cylinder (boom hoisting up) or the hydraulic line 51b. It is carried out by sending it to the second hydraulic chamber 54b through the cylinder to shorten the cylinder (lowering the boom). Further, the hydraulic line 51 is provided between the manual valve 52 and the undulating cylinder 54.
An electromagnetic valve 53 for opening and closing a and 51b is provided. The switching of the electromagnetic valve 53 is also performed based on the switching signal from the controller 40.
It is output based on the ground reaction forces f _{1 to} f ₄ calculated by the hydraulic signals from the pressure sensors 31 to 34 described above.

A specific operation of the vehicle body horizontal installation device having the above configuration will be described.

When the boom storage detector 35 detects that the boom 3 is in the retracted state at the start of work, the hydraulic control valve 20 is operated to operate the hydraulic oil of the hydraulic source 5 in order to horizontally install the vehicle body 2. Each jack cylinder 11d-1
Inner post 1 led to 4d and pulled in until then
1b-14b is extended and each earthing | grounding board 11a-14a is earth | grounded. After this, each inner post 11b-14
Although the vehicle body 2 is supported by extending b, the extension amount of each inner post 11b to 14b is independently controlled based on the inclination signal from the inclination detector 8 so that the vehicle body 2 becomes horizontal.

In this way, after this device operates as a device for horizontally installing the vehicle body 2, the operator operates the boom 3.

When the boom is operated as shown in FIG. 3, the work bucket 4
A moment M _B corresponding to the loaded load on the boom 3 and the amount of extension and undulation of the boom 3 is generated, and this moment M _B acts to tilt the vehicle body 2 to the side where the boom 3 is located. Further, the magnitudes of the ground reaction forces f _{1 to} f ₄ applied to the jacks 11 to 14 change in accordance with the magnitude and working direction of the moment M _B and the projecting width of the jacks 11 to 14. From this, when any one of the ground reaction forces f _{1 to} f ₄ approaches 0, the vehicle body 2 becomes unstable,
Since there is a risk of tipping over, in the above-described tipping prevention device, these ground reaction forces f _{1 to} f ₄ are compared and a safety factor is taken into consideration. For example, the minimum ground reaction force is a predetermined ratio to the maximum ground reaction force. In the following cases, the working range of the boom 3 is regulated as described below so that the minimum ground reaction force does not decrease further.

However, the boom 3 is extended and retracted and revolved by the operation of the reciprocating cylinder 64 and the revolving motor (not shown) shown in FIG. 2, respectively, as described above, but their control is the same as the control of the hoisting cylinder 54. So, below,
Only the control of the undulating cylinder 54 will be described.

Now, as shown in FIG. 3, it is assumed that the boom 3 is upright with a certain ups and downs and extends toward the jacks 11 and 12. From this state, when the manual valve 52 shown in FIG. 1 is moved to the boom hoisting and lowering side in an attempt to tilt the boom 3 until the hoisting angle becomes smaller than the current hoisting angle, the hoisting cylinder 54 shortens and the boom 3 falls. At this time, the boom storage detector 35 outputs a signal indicating that the boom 3 is not stored.
In the fall prevention device within 0, the ground reaction forces f _{1 to} f ₄ calculated based on the signals from the pressure sensors 31 to 34 as described above are compared. At this time, if one of the ground reaction forces f ₃ and f ₄ of the jacks 13 and 14 not on the turning side of the boom 3 is less than or equal to a predetermined ratio of f ₁ or f ₂ , the vehicle body 2 approaches an unstable state. As the controller 40
Outputs a switching signal, the electromagnetic valve 53 is switched to the closed position, the hydraulic lines 51a and 51b are shut off, the shortening operation of the hoisting cylinder 54 is stopped, and the hoisting lowering operation of the boom 3 is stopped. Further, the pressure oil from the hydraulic power source 50, which has no place to go because the hydraulic lines 51a and 51b are cut off,
The relief valve 55 returns to the oil tank 55. In addition to stopping the operation of the boom as described above, an alarm may be sounded to notify the operator of this state.

In this state, in order to avoid the unstable state of the vehicle body 2, the electromagnetic valve 53 is switched to the open position to open the hydraulic lines 51a and 51b only when the manual valve 52 is set to the boom starting side, and the hoisting cylinder is lifted. 54 is extended and the boom 3 is erected.

However, the electromagnetic valve 53 is switched to the open position even when the ground reaction forces f ₃ and f ₄ are increased by the turning or shortening of the boom 3 to avoid the unstable state of the vehicle body 2.

In this example, the ground reaction force is detected from the working hydraulic pressure of the jack cylinder, but instead of this, compressive stress applied to the jack, bending stress of the outrigger box or outrigger boom for mounting the jack cylinder on the vehicle body, etc. are detected. Alternatively, the ground reaction force may be directly detected.

Further, in this example, the jacks 11 to 14 are connected to the outrigger boxes 15a to 18a and the outrigger beam 15 respectively.
Although it is attached to the vehicle body via b to 18b, the jack may be directly attached to the vehicle body frame.
Further, as the jack, a jack cylinder only having a ground plate attached to the lower end may be used.

C. Effects of the Invention As described above, the present device detects that the boom is stored when the vehicle body is installed horizontally at the start of work, and detects the boom cylinder based on the signals from the pressure detector and the tilt detector. When the boom is in operation by controlling the expansion and contraction of the vehicle and the boom is in operation, it operates as a moment limiter that prevents the vehicle from falling based on the signal from the pressure detector. In this way, the present device also functions as a moment limiter by using the control hydraulic pressure of the jack used when functioning to horizontally install the vehicle body. In this way, by having both functions in one device, it is possible to reduce the size and weight as compared with the conventional case where the horizontal body installation device and the moment limiter are separately mounted. Furthermore, whether or not the function of this device as a moment limiter is normal can be confirmed by monitoring the ground reaction force received by the jack cylinder without operating the boom to the limit of the work allowable range. Can be improved.

[Brief description of drawings]

FIG. 1 is a control circuit diagram showing a vehicle body horizontal installation device according to the present invention, FIG. 2 is a perspective view showing an aerial work vehicle equipped with the vehicle body horizontal device, and FIG. 3 is provided on the vehicle body. FIG. 4 is a schematic view showing the operating state of the boom, and FIG. 4 is a perspective view showing the structure of the jack. 2 ... vehicle body, 8 ... tilt detector 11-14 ... jack 20 ... control valve 31-34 ... pressure sensor 35 ... boom storage detector 40 ... controller, 53 ... electromagnetic valve 54 ... undulation Cylinder, 64 ... Telescopic cylinder

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B66F 11/04 7515-3F G01L 7/00 A 9009-2F

Claims (1)

[Scope of utility model registration request] 1. A vehicle body horizontal installation device for mounting a work vehicle horizontally using a plurality of jack cylinders mounted on a work vehicle having a boom capable of telescopic, undulating or turning, and lifting and lowering a ground plate attached to a lower end. In, a boom storage detector for detecting whether or not the boom is in a retracted state, a pressure detector provided for each of the jack cylinders, for detecting a control hydraulic pressure of the jack cylinders, and for detecting an inclination of the vehicle body. When the tilt detector and the boom retractor detect that the boom is not in the retracted state, the stable state of the work vehicle is determined based on the detection signal from the pressure detector. The pressure detector and the tilt detector when the boom is in the retracted state by the device and the boom retractor. Based on the detection signal, the vehicle body horizontal installation apparatus, characterized in that the body is composed of a controller for extending and retracting operation of each jack cylinder so that the horizontal.