Patent Description:
In the related art, in a work vehicle such as a crane, a high-place work vehicle, or a ladder vehicle that performs a work by extending an in-vehicle boom or ladder, a posture of a vehicle body is stabilized by grounding an outrigger at the time of the work. The vehicle body is supported by contracting the outrigger to be in a non-grounding state at the time of traveling and by extending the outrigger to be in a grounding state at a work site.

When the vehicle body posture is stabilized by using the outrigger in this manner, all of a plurality of outriggers need to be grounded. Thus, there is known a configuration in which a ground sensor for detecting that the outrigger is grounded is provided to detect whether or not the outrigger is grounded (see, for example, Patent Literature <NUM>). In the ground sensor of the related art, a sensor such as a limit switch, a potentiometer, or a load cell is provided in the outrigger, and whether or not the outrigger is grounded is detected on the basis of an extension/contraction amount of the outrigger, a ground reaction, and the like. In addition, the ground sensor provided in each outrigger is connected to an in-vehicle controller via a wiring.

Japanese Patent Application Publication <CIT> provides a display control unit configured to perform control, such that the generated space image information is displayed on a display unit in a communication source. Japanese Patent Application Publication <CIT> is directed to allow the operation of a boom in a range in which the stability of the car body of the crane is not diminished, even when it is determined that one jack of the car body is not grounded.

<CIT> provides a vehicle body levelling device for a working vehicle having outriggers, for stabilizing the vehicle body while in service.

As described above, the ground sensor is provided in each outrigger, and a detection signal is sent to the controller via the wiring. Thus, as many ground sensors as the number of outriggers are required, and wirings connecting the ground sensors and the controller are required. Accordingly, since cost is required by the number of sensors and the number of wirings and the wirings are laid across a traveling body and a movable part, there is a disconnection concern and the like as compared with a case where a wiring is provided in a non-drive unit, and thus, there is a concern that reliability is reduced.

The present disclosure has been made in view of the above problems, and an object thereof is to provide an outrigger control device advantageous in terms of cost and reliability.

According to a first aspect, the present invention provides an outrigger control device according to independent claim <NUM>. Further Aspects of the present invention are set forth in the dependent claims, the drawings and the following description. An outrigger control device of the present disclosure includes a plurality of outriggers that is provided in a traveling body, and is extendable/contractible between a non-grounding state where the traveling body is not supported and a grounding state where the traveling body is supported, an inclination sensor that is provided in the traveling body, and is able to detect an inclination of the traveling body, and a controller that controls an extension/contraction action of the outrigger and acquires a detection signal of the inclination sensor. The controller includes a grounding determination processing unit that controls the outrigger to perform a predetermined grounding determination action and determines whether or not the outrigger is in the grounding state on the basis of a detected value of the inclination sensor at the time of the grounding determination action.

In the outrigger control device of the present disclosure, it is determined whether the outrigger is in the grounding state or the non-grounding state on the basis of the grounding determination action of the outrigger and the detected value of the inclination sensor provided in the traveling body. Thus, it is not necessary to provide the ground sensor in each outrigger, and the wiring for connecting each ground sensor and the controller is not necessary. Accordingly, the number of ground sensors and the number of wirings are reduced, and thus, cost can be reduced. There is no disconnection concern, and thus, reliability can be improved.

Hereinafter, a best mode for realizing the outrigger control device of the present disclosure will be described with reference to the drawings.

Hereinafter, an outrigger control device A1 of a first embodiment will be described. The outrigger control device A1 is mounted on a crane CC illustrated in <FIG> and <FIG>. Thus, first, the crane CC will be described.

The crane CC includes a traveling body <NUM>, a boom <NUM>, and an outrigger <NUM>. The traveling body <NUM> is a vehicle body of a vehicle that can be self-propelled by wheels <NUM>.

The boom <NUM> is provided to be able to rise and fall and to be extendable/contractible on a slewing platform <NUM> provided in the traveling body <NUM> so as to be able to be slewed by <NUM> degrees in a horizontal direction. Note that the rising and falling of the boom <NUM> are executed by extension/contraction of a derricking cylinder <NUM> provided between the boom <NUM> and the slewing platform <NUM>. In addition, the extension/contraction of the boom <NUM> is executed by extension/contraction of a telescopic cylinder <NUM> (see <FIG>) provided inside the boom.

Note that, in <FIG>, the boom <NUM> is in a laid state where a length is shortened to a minimum length, and represents a housed posture in which a distal end thereof is directed forward of the traveling body <NUM> (a posture when the traveling body <NUM> travels). In addition, a work can be performed by slewing the slewing platform <NUM>, extending the boom <NUM> from the housed posture, or standing the boom.

The outrigger <NUM> is a so-called H-shaped outrigger, and includes first to fourth outriggers <NUM>, <NUM>, <NUM>, and <NUM>. That is, the traveling body <NUM> includes a pair of left and right first outrigger <NUM> and second outrigger <NUM> provided on a front side, and a pair of left and right third outrigger <NUM> and fourth outrigger <NUM> provided on a rear side.

Note that, in the description of the present specification, front, rear, left, right, up, and lower directions are based on a direction by the crane CC. In the drawings, a direction of an arrow FR is defined as the front, a direction of an arrow RR is defined as the rear, a direction of an arrow L is defined as the left, a direction of an arrow R is defined as the right, a direction of an arrow UP is defined as the upper, and a direction of an arrow DN is defined as the lower. In addition, since the outriggers <NUM> to <NUM> having the same configuration are provided symmetrically, in the following description, the reference signs <NUM> to <NUM> are used only when a specific outrigger among the four outriggers is indicated, and the outrigger <NUM> is simply used when the specific outrigger is not indicated.

The outrigger <NUM> is provided in the traveling body <NUM>, and includes, as illustrated in <FIG>, beams <NUM> extendable/contractible in a left-right direction, and jacks <NUM> provided at distal end portions of the beams <NUM> and extendable/contractible in an upper-lower direction. In addition, substantially disk-shaped floats 32a are provided at lower end portions of the jacks <NUM>, and the floats 32a are grounded when the outrigger <NUM> is grounded. Then, the traveling body <NUM> can be moved up or down by causing the floats 32a to be grounded and vertically extending/contracting the jacks <NUM>.

In addition, the beams <NUM> and the jacks <NUM> have hydraulic cylinders <NUM>, <NUM>, <NUM>, and <NUM> (see <FIG>) connected to a hydraulic source (for example, a hydraulic pump and an oil tank) not illustrated.

These hydraulic cylinders <NUM> to <NUM> extend/contract by supplying and discharging hydraulic pressures on the basis of an operation of an outrigger hydraulic pressure control unit <NUM> (see <FIG>) controlled by a controller <NUM>. Accordingly, the beam <NUM> of each of the outriggers <NUM> to <NUM> extends/contracts in the left-right direction, and the jack <NUM> extends/contracts in the upper-lower direction. Note that the outrigger hydraulic pressure control unit <NUM> includes switching valves that are controlled by the controller <NUM> and supply and discharge hydraulic pressures to and from the hydraulic cylinders <NUM>, <NUM>, <NUM>, and <NUM>, respectively.

Note that the controller <NUM> controls a slewing platform drive unit 21a that drives the slewing platform <NUM> to slew, and a boom hydraulic pressure control unit <NUM> that extends/contracts the derricking cylinder <NUM> and the telescopic cylinder <NUM> of the boom <NUM>. In addition, the controller <NUM> is connected to an operation unit <NUM> for causing the boom <NUM> and the outrigger <NUM> to act, and a sensor group <NUM> for detecting action states of the boom <NUM> and the outrigger <NUM>.

The sensor group <NUM> includes a sensor that detects the posture of the boom <NUM> and a slewing angle of the slewing platform <NUM> and an inclination sensor <NUM> that detects an inclination angle of the traveling body <NUM> in addition to a sensor that detects the hydraulic pressure supplied to each of the cylinders <NUM>, <NUM>, and <NUM> to <NUM> described above.

The inclination sensor <NUM> is a so-called biaxial inclinometer that detects the inclination of the traveling body <NUM> in a front-rear direction and the left-right direction. An existing sensor for detecting the inclination of the traveling body <NUM> can be applied as the inclination sensor <NUM> when the posture of the traveling body <NUM> is controlled such that the traveling body takes an optimum posture (basically, horizontal) during the work of the boom <NUM> of the crane CC.

Further, the controller <NUM> includes a grounding determination processing unit <NUM> that executes grounding determination processing of determining whether or not each of the outriggers <NUM> to <NUM> is grounded when the outrigger <NUM> acts to change from a non-grounding state to a grounding state.

Hereinafter, a flow of the grounding determination processing executed by the grounding determination processing unit <NUM> will be described. In the first embodiment, the grounding determination processing is executed together with a grounding action of the outrigger <NUM>, and a flow of the processing will be described with reference to a flowchart of <FIG>.

First, in first step S101, the controller <NUM> designates one of the outriggers <NUM> in the non-grounding state. Although this designation may be performed on the basis of a manual operation by an operator, in the first embodiment, the controller <NUM> automatically designates the first outrigger <NUM> to the fourth outrigger <NUM> as the outriggers <NUM> to be sequentially grounded. Accordingly, in a state where all the outriggers <NUM> to <NUM> are not grounded, first, the controller <NUM> designates the first outrigger <NUM>.

In next step S102, the controller <NUM> records, as an initial value T0, a detected value (inclination state) of the inclination sensor <NUM> at this time. Then, in subsequent step S103, the controller <NUM> continuously extends the jack <NUM> of the outrigger <NUM> (first, the first outrigger <NUM>) designated in step S101. Note that, in the first embodiment, the beam <NUM> is extended to a side of the traveling body <NUM> by a predetermined amount before an extension action of the jack <NUM> is performed. An extension action of the beam <NUM> may be performed on the beams <NUM> of all the outriggers <NUM> in advance at the start of the execution of the grounding determination processing, or may be performed on the beam <NUM> of the outrigger <NUM> to be grounded when the processing of step S103 is performed.

In next step S104, the controller <NUM> acquires a detection signal from the inclination sensor <NUM>, and determines whether or not a difference between a detected value Tn of the inclination sensor <NUM> and the initial value T0 recorded in step S102 exceeds a preset threshold Tlim. When the difference between the detected value Tn and the initial value T0 exceeds the threshold Tlim, the processing proceeds to step S105, and the controller <NUM> determines that the outrigger is in the grounding state. On the other hand, when the difference between the detected value Tn and the initial value T0 does not exceed the threshold Tlim in step S104, the processing proceeds to step S106, and the controller <NUM> determines that the outrigger is in the non-grounding state. The processing returns to step S103, and the extension action of the outrigger <NUM> is continued.

Note that the threshold Tlim is set in advance on the basis of an inclination amount of the traveling body <NUM> generated when the outrigger <NUM> is grounded. That is, when the outrigger <NUM> in the non-grounding state is extended and grounded and continues to be extended in this state, one portion of the traveling body <NUM> is displaced upward, and the inclination state of the traveling body <NUM> changes. Accordingly, a change in the inclination amount generated when the designated one outrigger <NUM> is extended and grounded and is further extended by a necessary amount in order for the outrigger <NUM> to support the traveling body <NUM> is obtained by an experiment or a simulation. Then, an optimum threshold Tlim is set in order to determine that the outrigger <NUM> is grounded and extended by a necessary amount on the basis of the obtained change in the inclination amount.

When it is determined that the outrigger is in the grounding state in step S105, in step S107, the controller <NUM> stops the extension action of the outrigger <NUM> designated in step S101, and the processing proceeds to step S108.

In step S108, the controller <NUM> determines whether or not all the first to fourth outriggers <NUM> to <NUM> are in the grounding state. When all the outriggers <NUM> to <NUM> are not in the grounding state, the processing proceeds to step S109, and the controller <NUM> controls the outrigger <NUM> that is not grounded to execute the grounding action. In addition, when all the four outriggers <NUM> to <NUM> are in the grounding state, the processing ends.

Then, when the outrigger <NUM> that is not grounded is caused to execute the grounding action in step S109, the processing returns to step S101, and the controller <NUM> designates the outrigger <NUM> to be grounded next from among the outriggers <NUM> in the non-grounding state. In the first embodiment, as described above, the outrigger <NUM> to be grounded is designated in the order of the first outrigger <NUM> to the fourth outrigger <NUM>.

Note that, in step S102, the controller <NUM> sets the detected value of the inclination sensor <NUM> before the next outrigger <NUM> is extended as the initial value T0 every time. For example, when the first outrigger <NUM> is grounded and extended by a predetermined amount, the traveling body <NUM> changes from a horizontal state to an inclination state where a left front side is raised. Thus, when the second outrigger <NUM> is designated and extended, the controller <NUM> records, as the initial value T0, the detected value of the inclination sensor <NUM> in a state where the left front side of the traveling body <NUM> before the second outrigger <NUM> is extended is raised and inclined. Then, the controller determines whether the next second outrigger <NUM> is in the grounding state and is further raised by a predetermined amount on the basis of the difference between the initial value T0 and the subsequent detected value Tn of the inclination sensor <NUM>.

The above pieces of processing of steps S101 to S109 are repeated for each of the four outriggers <NUM> to <NUM>, and thus, all the four outriggers <NUM> to <NUM> can be grounded and can be raised by a predetermined amount. Note that the order of the outriggers <NUM> to be grounded by being designated and extended is not limited to this order, and may be performed in, for example, another order such as a clockwise order or a counterclockwise order when viewed from above.

Accordingly, the grounding state of each of the four outriggers <NUM> to <NUM> can be detected by the action of each of the outriggers <NUM> to <NUM> and one inclination sensor <NUM>. Thus, the number of unnecessary ground sensors and the number of unnecessary wirings are also large, and the effects of the cost and reliability of the above (<NUM>) are further enhanced.

Next, another embodiment of the outrigger control device will be described. Note that, in the description of a second embodiment, constituent components common to the first embodiment are denoted by the same reference signs as those of the first embodiment and the description thereof is omitted, and only differences from the first embodiment will be described.

The second embodiment is a modification example of the first embodiment, and is different from the first embodiment in the action of the outrigger <NUM> and the grounding determination processing on the basis of the detected value of the inclination sensor <NUM>.

Hereinafter, a flow of grounding determination processing by an outrigger control device A2 of the second embodiment will be described. In the grounding determination processing in the second embodiment, first, the grounding actions of all the outriggers <NUM> to <NUM> are performed, and thereafter, it is determined whether or not each of the outriggers <NUM> to <NUM> is in the grounding state.

Here, first, the grounding action of each outrigger <NUM> will be described. In this grounding action, the beams <NUM> of the four outriggers <NUM>, <NUM>, <NUM>, and <NUM> are extended in the left-right direction as illustrated in <FIG>, and the jacks <NUM> are further extended until it is estimated that the jacks are in the grounding state.

The extension of the jacks <NUM> may be performed by the operator manually operating the operation unit <NUM> or may be performed by automatic control by the controller <NUM>. When the jacks <NUM> are extended by the manual operation, for example, it is determined whether or not the jacks are grounded on the basis of a bodily sensation caused by the posture change of the traveling body <NUM> due to a ground reaction. In this case, the extension action of the jacks <NUM> is stopped at a point in time at which the operator senses the posture change of the traveling body <NUM> when the jacks <NUM> are grounded and estimates that the jacks are grounded.

In addition, in the grounding action of the jack <NUM> by the automatic control, for example, the extension action of the jack <NUM> is performed for a predetermined time necessary for the beam <NUM> to be extended and then grounded.

In this manner, after the jack <NUM> is extended until it is estimated that the jack <NUM> is grounded, the controller <NUM> (grounding determination processing unit <NUM>) subsequently determines whether or not the jack <NUM> is reliably grounded.

Hereinafter, the grounding determination processing of the second embodiment by the controller <NUM> (grounding determination processing unit <NUM>) will be described with reference to a flowchart illustrated in <FIG>. Note that the grounding determination processing may be started when the operator performs a predetermined start operation by the operation unit <NUM>, or may be automatically started after the extension action when the outrigger <NUM> is extended by the automatic control as described above.

First, in first step S201, the controller <NUM> extends/contracts one jack <NUM> of the four outriggers <NUM> to <NUM> as the grounding determination action. In this extension/contraction action, the extension action and the contraction action of the jack <NUM> are alternately repeated, and are executed a predetermined number of times or for a predetermined time.

In next step S202, the controller <NUM> acquires the detection signal of the inclination sensor <NUM> when the extension/contraction action of the jack <NUM> of the outrigger <NUM> is performed in step S201, and determines whether or not the change amount of the detected value of the inclination sensor <NUM> exceeds a preset threshold. Then, when the change amount exceeds the threshold (Yes), the controller <NUM> determines that the outrigger <NUM> that has performed the extension/contraction action of the jack <NUM> in step S201 is in the grounding state (step S203). On the other hand, when the change amount is equal to or less than the threshold (No), the controller <NUM> determines that the outrigger <NUM> that has performed the extension/contraction action of the jack <NUM> in step S201 is in the non-grounding state (step S204).

That is, when the jack <NUM> of one (for example, the outrigger <NUM>) of the four outriggers <NUM> to <NUM> is extended/contracted in a state where the float 32a is grounded, the traveling body <NUM> moves up and down by a predetermined amount at one point of the four grounded points, and the inclination angle of the traveling body <NUM> changes. Thus, the change amount of the inclination angle when one jack <NUM> is extended/contracted by a predetermined amount in a state where the four outriggers <NUM> are grounded is obtained in advance by an experiment or a simulation, and the threshold is set on the basis of the change amount. Accordingly, in step S202, when the change amount exceeds the threshold, it is possible to determine that the float 32a of the outrigger (for example, the first outrigger <NUM>) is grounded.

On the other hand, when the extended/contracted outrigger <NUM> is not grounded, the traveling body <NUM> hardly moves up or down. Thus, when the change amount of the detected value of the inclination sensor <NUM> does not exceed the threshold, it is possible to determine that the float 32a of the outrigger (for example, the first outrigger <NUM>) is not grounded.

Then, when it is determined that the float 32a is in the non-grounding state, the jack <NUM> of the corresponding outrigger (for example, the first outrigger <NUM>) is extended, and then the grounding determination processing in steps S201 to S204 is performed again. This action is repeatedly executed until it is determined that the float 32a is grounded.

The grounding determination processing in steps S201 to S204 is sequentially performed for the four outriggers <NUM> to <NUM> one by one, and all the four outriggers <NUM> to <NUM> are reliably grounded on the basis of the determination result.

Note that, for example, although the traveling body <NUM> is horizontally controlled by controlling the posture of the traveling body <NUM> after all the outriggers <NUM> are grounded, this control itself is not a target of the present disclosure, and thus, the description thereof will be omitted.

As described above, in the outrigger control device A2 of the second embodiment, the grounding determination processing unit <NUM> extends/contracts the outrigger <NUM> as the grounding determination action, and determines the grounding state on the basis of the change in the detected value of the inclination sensor <NUM> when the extension/contraction action is performed.

Accordingly, in the second embodiment, similarly to the above (<NUM>), (<NUM>), and (<NUM>), the number of ground sensors and the number of wirings provided in the four outriggers <NUM> are reduced, and thus, cost can be reduced. There is no disconnection concern, and thus, reliability can be improved. In addition, the grounding state of each of the four outriggers <NUM> to <NUM> can be detected by the action of each of the outriggers <NUM> to <NUM> and one inclination sensor <NUM>. In addition, the posture change by the extended/contracted outrigger <NUM>, that is, the grounding state can be detected on the basis of the detected value of the inclination sensor <NUM> regardless of the posture of the traveling body <NUM> before the outrigger <NUM> is extended.

Although the embodiments have been described above, the specific configuration of the outrigger control device of the present disclosure is not limited to the above-described embodiments, and changes, additions, and the like in design are allowed without departing from the gist of the present disclosure.

For example, in the embodiments, although the example in which the outrigger control device is applied to the crane CC has been described, the traveling body to which the outrigger control device is applied is not limited to the crane CC, and any traveling body may be used as long as the traveling body includes the plurality of outriggers. Specifically, the present disclosure can also be applied to an industrial machine such as an excavation device in addition to a work vehicle such as a high-place work vehicle and a ladder vehicle other than the crane.

In addition, in the embodiments, although the four outriggers <NUM> to <NUM> have been described as the plurality of outriggers <NUM>, the number of outriggers is not limited to four as long as the plurality of outriggers is provided. For example, the present disclosure can also be applied to an example in which a pair of outriggers are provided on the left and right. Further, in the embodiments, although the outrigger <NUM> including the beam <NUM> and the jack <NUM> has been described, the present disclosure is not limited thereto, and any outrigger may be used as long as the outrigger at least extends/contracts and is grounded. In addition, as long as the jack extends/contracts so as to be able to move the traveling body <NUM> in the upper-lower direction, the present disclosure is not limited to the jack that extends/contracts in a vertical direction like the jack <NUM> described in the embodiments. For example, the jack may extend/contract in other directions such as the jack that vertically extends/contracts in an oblique direction as described in <CIT>.

In addition, in the embodiments, although the grounding state at the time of the grounding determination processing has been determined on the basis of the change amount from the initial value T0 and the change amount of the detected value of the inclination sensor <NUM> when the outrigger <NUM> is extended/contracted, the present disclosure is not limited thereto. For example, the determination may be performed on the basis of whether or not a change rate of the detected value at the time of extension/contraction of the outrigger <NUM> exceeds a threshold on the basis of the change rate. That is, when the outrigger <NUM> is grounded, since a change rate of the inclination angle at the time of the extension action or the extension/contraction action of the outrigger <NUM> becomes faster than that when the outrigger is not grounded, the grounding state of the outrigger <NUM> can be determined on the basis of the change rate.

In addition, in the embodiments, although the example in which the extension actions or the extension/contraction actions of the outriggers <NUM> are performed one by one in the grounding determination processing has been described, the present disclosure is not limited thereto. For example, the grounding determination processing may be performed by causing the plurality of outriggers <NUM> to simultaneously act. Specifically, as in the embodiments, when the four outriggers <NUM> are provided and the four outriggers are simultaneously extended or extended/contracted, the traveling body <NUM> moves up and down at a substantially constant inclination when all the four outriggers are grounded. On the other hand, when there is the outrigger <NUM> that is not grounded, a displacement amount in the direction of the outrigger <NUM> that is not grounded in the traveling body <NUM> is small, and the inclination sensor <NUM> is inclined in the direction of the outrigger <NUM> that is not grounded. It may be determined whether the outrigger is in the grounding state or the non-grounding state on the basis of the detection of the inclination state due to such a difference in the displacement amount. Similarly, it may be determined whether the outrigger is in the grounding state or the non-grounding state on the basis of the detection of the inclination state due to the difference in the displacement amount by causing the pair of left and right outriggers <NUM> to simultaneously act.

Claim 1:
An outrigger control device (A2) comprising:
a plurality of outriggers (<NUM>) that is provided in a traveling body (<NUM>), and is extendable/contractible between a non-grounding state where the traveling body (<NUM>) is not supported and a grounding state where the traveling body (<NUM>) is supported;
an inclination sensor (<NUM>) that is provided in the traveling body (<NUM>), and is able to detect an inclination of the traveling body (<NUM>); and
a controller (<NUM>) that controls an extension/contraction action of the outrigger (<NUM>) and acquires a detection signal of the inclination sensor (<NUM>), the outrigger control device (A2) being characterized in that
the controller (<NUM>) extends/contracts the outrigger (<NUM>), and determines whether or not the outrigger is in the grounding state on the basis of a change in the detected value of the inclination sensor (<NUM>) when the extension/contraction action is performed.