JP2014218360A - Device for detecting stroke end of derricking cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stroke end detection device capable of detecting the stroke end of a derricking cylinder with inexpensive configuration.SOLUTION: A stroke end detection device is provided with a ground angle detector 11, a jack-up state detector 12 and stroke end determination means 20. The stroke end determination means 20 obtains a stroke end ground angle Θfrom a stroke end machine angle Θ, and a machine body inclining angle α being a ground angle θwhen the jack-up state detector 12 detects, and compares the stroke end ground angle Θwith a present ground angle θto determine the stroke end. The stroke end can be normally detected even if the machine body 30 inclines from a horizontal plane G. Since the ground angle detector 11 used for an overload protection device can be used, there is no need to install a new detector and thereby, the stroke end can be detected with inexpensive configuration.

Description

  The present invention relates to a stroke end detection device for an undulating cylinder. More specifically, the present invention relates to a stroke end detection device for detecting a stroke end of a hoisting cylinder that raises and lowers a boom.

  A work vehicle having a boom such as a mobile crane is provided with an overload prevention device in order to ensure stability. In general, an overload prevention device includes a length detector that detects the length of a boom, a ground angle detector that detects an angle (ground angle) of the boom with respect to a horizontal plane, and a swing angle detector that detects a swing angle of the boom. And a hoisting reaction force detector for detecting a load acting on the hoisting cylinder for hoisting the boom. Calculate the limit value of the overturning moment from the boom length detected by the length detector, the ground angle of the boom detected by the ground angle detector, and the boom turning angle detected by the turning angle detector, When the moment applied to the boom detected by the undulation reaction force detector exceeds the limit value of the overturning moment, the boom operation is restricted or an alarm is issued to prevent the work vehicle from overturning. Yes.

  A hydraulic sensor may be used as the undulation reaction force detector. A hydraulic pressure sensor is provided in an oil passage connected to the oil chamber on the extension operation side of the hoisting cylinder, and a load acting on the hoisting cylinder is detected from the hydraulic pressure measured by the hydraulic sensor. In such a undulation reaction force detector, when the undulation cylinder reaches the extension stroke end (stroke end of the boom raising side), the hydraulic oil is trapped in the oil chamber, and the load acting on the undulation cylinder is accurately determined from the hydraulic pressure. It cannot be detected. Therefore, in the overload prevention device that uses a hydraulic sensor as the undulation reaction force detector, the stroke end of the undulation cylinder is detected so that the detected value of the undulation reaction force detector is not used. .

  Document 1 discloses a technique for detecting the stroke end of an undulating cylinder using a switch. However, the provision of a new switch that is not necessary as an overload prevention device has the problem of increasing the cost of the work vehicle.

  Reference 1 also discloses a technique for detecting the stroke end by comparing the boom undulation angle at the stroke end of the undulation cylinder with the detection value of the undulation angle detector. However, since the undulation angle detector provided in the overload prevention device is a ground angle detector that detects the ground angle of the boom, if the body of the work vehicle is inclined with respect to the horizontal plane, the detection value of the ground angle detector There is a problem that the stroke end cannot be normally detected because the angle of the boom with respect to the aircraft body (the angle between the aircraft) is different. In particular, the load-type truck crane has two outriggers and is inclined in the front-rear direction so that the front of the vehicle becomes higher. Further, a large mobile crane has four outriggers and basically the vehicle is horizontal, but it may not be horizontal depending on the situation. In such a case, the stroke end cannot be normally detected by the conventional method.

  In order to solve this problem, a machine angle detector that detects the machine angle of the boom may be provided. However, a new machine angle detector that is not necessary as an overload prevention device may be provided. There is a problem that the cost increases.

JP 2009-62183 A

  In view of the above circumstances, an object of the present invention is to provide a stroke end detection device capable of detecting a stroke end of a hoisting cylinder with an inexpensive configuration.

A stroke end detection device for a hoisting cylinder according to a first aspect of the present invention includes an airframe, an outrigger provided on the airframe, a boom provided to be hoistable with respect to the airframe, and a hoisting cylinder for hoisting the boom. In a vehicle, a device for detecting a stroke end of the hoisting cylinder, a ground angle detector for detecting a ground angle that is an angle with respect to a horizontal plane of the boom, and a jackup for detecting completion of jackup of the outrigger Stroke end pair machine which is an angle with respect to the body of the boom when the state detector, detection values of the ground angle detector and the jack-up state detector are inputted and the hoisting cylinder is a stroke end Stroke end determination means in which an angle is stored in advance, and the stroke The end determination means uses the ground angle when the jack-up state detector detects the airframe inclination angle, and the undulation cylinder is at the stroke end from the stroke end airframe angle and the airframe inclination angle. A stroke end ground angle which is an angle with respect to a horizontal plane of the boom is obtained, and the stroke end ground angle is compared with the current ground angle to determine whether or not the undulating cylinder is a stroke end. .
According to a second aspect of the present invention, there is provided a hoisting cylinder stroke end detecting device comprising the turning angle detector for detecting the turning angle of the boom according to the first invention, wherein the stroke end determining means receives the detection value of the turning angle detector. The stroke end ground angle depending on the turning angle of the boom is obtained from the stroke end facing machine angle and the machine body inclination angle, and the stroke end ground angle at the current turning angle and the current grounding angle are obtained. An angle is compared to determine whether or not the undulating cylinder is at the stroke end.
According to a third aspect of the present invention, the stroke end detecting device for the undulating cylinder in the second invention is characterized in that the stroke end determining means is based on the ground angle in at least two directions when detected by the jack-up state detector, Determining the aircraft tilt angle in the aircraft tilt direction, and determining the stroke end ground angle depending on the turning angle of the boom from the stroke end vs. aircraft angle, the aircraft tilt angle, and the aircraft tilt direction. To do.
A hoisting cylinder stroke end detecting device according to a fourth aspect of the present invention is the first, second or third aspect of the present invention, further comprising a boom retracted state detector for detecting that the boom is in the retracted state, When the detection value of the boom retracted state detector is input and the jack retracted state detector detects when the boom retracted state detector detects, the stroke end ground angle is stored, and the boom retracted When the state detector does not detect, the stored stroke end ground angle is acquired.
A lifting cylinder stroke end detection device according to a fifth aspect of the present invention includes an airframe, an outrigger provided in the airframe, a boom provided so as to be able to hoist up the airframe, and a hoisting cylinder for raising and lowering the boom. In a vehicle, a device for detecting a stroke end of the hoisting cylinder, a ground angle detector for detecting a ground angle that is an angle with respect to a horizontal plane of the boom, and a jackup for detecting completion of jackup of the outrigger Stroke end pair machine which is an angle with respect to the body of the boom when the state detector, detection values of the ground angle detector and the jack-up state detector are inputted and the hoisting cylinder is a stroke end Stroke end determination means in which an angle is stored in advance, and the stroke The ground determination means uses the ground angle when the jack-up state detector detects the airframe inclination angle, and the airframe angle is an angle of the boom with respect to the airframe from the airframe inclination angle and the current ground angle. The stroke end machine angle is compared with the machine angle to determine whether or not the undulating cylinder is at the stroke end.

According to the first invention, by comparing the stroke end ground angle obtained based on the stroke end ground angle stored in advance and the detection value of the ground angle detector with the current ground angle, the undulation cylinder is Since it is determined whether or not it is the stroke end, the stroke end can be normally detected even if the aircraft is inclined with respect to the horizontal plane. In addition, since the ground angle detector used in the overload prevention device can be used, it is not necessary to provide a new detector, and the stroke end of the undulating cylinder can be detected with an inexpensive configuration.
According to the second invention, since the ground angle and the stroke end ground angle are compared in consideration of the turning angle of the boom, even when the boom is turned from the state where the jack-up is completed, the stroke end of the hoisting cylinder is set. It can be detected normally.
According to the third aspect of the invention, since the stroke end ground angle is obtained in consideration of the airframe tilt direction, the stroke end of the hoisting cylinder is normal even if the direction of the boom when the jack-up is completed and the airframe tilt direction are deviated. Can be detected.
According to the fourth aspect, since the stored stroke end ground angle is acquired when the boom is not in the retracted state, the stroke end ground angle is set even when the work is resumed after the work is finished without storing the boom. It can be a correct value.
According to the fifth aspect, by comparing the machine angle obtained based on the detection value of the ground angle detector with the stroke end machine angle stored in advance, whether or not the undulation cylinder is the stroke end. Therefore, the stroke end can be normally detected even if the aircraft is tilted with respect to the horizontal plane. In addition, since the ground angle detector used in the overload prevention device can be used, it is not necessary to provide a new detector, and the stroke end of the undulating cylinder can be detected with an inexpensive configuration.

It is a block diagram of stroke end detection device A concerning a 1st embodiment of the present invention. It is the whole flowchart of the stroke end detection apparatus A. It is a flowchart of the stroke end ground angle calculation process of the stroke end detection apparatus A. It is a flowchart of the stroke end determination process of the stroke end detection apparatus A. It is a block diagram of the stroke end detection apparatus B which concerns on 2nd Embodiment of this invention. It is a flowchart of the stroke end determination process of the stroke end detection device B. It is a flowchart of the stroke end ground angle calculation process of the stroke end detection apparatus C which concerns on 3rd Embodiment of this invention. It is a block diagram of the stroke end detection apparatus D which concerns on 4th Embodiment of this invention. It is a flowchart of the stroke end ground angle calculation process of the stroke end detection apparatus D. It is a whole flowchart of the stroke end detection apparatus E which concerns on 5th Embodiment of this invention. 4 is a flowchart of a machine body tilt angle calculation process of the stroke end detection device E. It is a flowchart of the stroke end determination process of the stroke end detection device E. It is a flowchart of the stroke end determination process of the stroke end detection apparatus F which concerns on 6th Embodiment of this invention. It is a flowchart of the body inclination angle calculation process of the stroke end detection apparatus G which concerns on 7th Embodiment of this invention. It is a flowchart of the body inclination angle calculation process of the stroke end detection apparatus H which concerns on 8th Embodiment of this invention. It is a side view of a loading type truck crane, (A) is in the state before jacking up, (B) is in the state where jacking up is completed. Body inclination angle alpha, which is an illustration of a ground angle theta _g, vs. machine angle theta _b, the stroke end ground angle theta _g, and the stroke end-to-machine angle theta _b. It is explanatory drawing of derivation | leading-out of Formula 2. It is explanatory drawing of derivation | leading-out of Formula 7.

Next, an embodiment of the present invention will be described with reference to the drawings.
The stroke end detection device according to the present invention is provided in a work vehicle having a boom such as a mobile crane or an aerial work vehicle, and is used for detecting a stroke end of a hoisting cylinder for raising and lowering the boom. Examples of the mobile crane include an all terrain crane, a rough terrain crane, a truck crane, and a loading truck crane. In the following, a load-type truck crane will be described as an example, but the same effect can be achieved by applying the present invention to other work vehicles.

First, the configuration of the loadable truck crane will be described.
As shown in FIG. 16 (A), the load-type truck crane M has a small crane 40 mounted on a vehicle frame 33 between a cab 31 and a loading platform 32 of a general-purpose truck 30. The general-purpose truck 30 corresponds to the “airframe” described in the claims.

  The small crane 40 includes a base 41 fixed on the vehicle frame 33, a post 42 provided so as to be rotatable with respect to the base 41, a boom 43 provided on an upper end portion of the post 42 so as to be raised and lowered, and a base 41. And a pair of outriggers 44 provided on the left and right sides of the. The outrigger 44 includes an extended beam 44a inserted into the base 41 and an outrigger jack 44b fixed to the tip of the extended beam 44a.

  The base 41 has a built-in turning motor, and the post 42 is turned by driving the turning motor. A hoisting cylinder 45 is attached between the post 42 and the boom 43. When the hoisting cylinder 45 is extended, the boom 43 rises, and when the hoisting cylinder 45 is contracted, the boom 43 falls. The boom 43 is configured in a telescopic shape and is expanded and contracted by an expansion cylinder. The post 42 has a winch built therein. A wire rope is guided from the winch to the tip of the boom 43 and hung around the hook 46 via a pulley at the tip of the boom 43, so that the hook 46 is connected to the tip of the boom 43. Hanging from the part.

  At the start of the crane operation, the overhanging beam 44a is extended, and the outrigger jack 44b is extended to ground the lower end float. Hereinafter, this operation is referred to as “jack-up”. By jacking up, the load-type truck crane M is supported and stable. At the end of the crane operation, the outrigger jack 44b is contracted, the overhanging beam 44a is retracted, and the outrigger 44 is stored.

  As shown in FIG. 16B, when the jack-up is performed, the front of the loading-type truck crane M is supported by the outrigger 44, so the suspension of the rear wheel 34 sinks, the suspension of the front wheel 35 extends, and the front becomes higher. Inclined in the front-rear direction. Large mobile cranes have four outriggers and are basically jacked up so that the aircraft is level, but there are cases where it cannot be completely leveled due to the inclination of the ground or the skill of workers. .

  The boom 43 is in a retracted state in cases other than crane work, such as during jack-up work or traveling on the general-purpose truck 30. The retracted state of the boom 43 in the loading-type truck crane M is a state in which the boom 43 is turned forward or backward of the general-purpose truck 30 and laid down.

  As shown in FIG. 17, in this specification, the angle of the airframe 30 (general-purpose truck 30) with respect to the horizontal plane G is referred to as an airframe inclination angle α. The airframe inclination angle α when the airframe 30 is placed on the horizontal plane G is set to zero.

The angle of the boom 43 with respect to the horizontal plane G is referred to as a ground angle θ _g . The ground angle θ _g when the machine body 30 is placed on the horizontal plane G and the boom 43 is in the retracted state is set to zero. An angle relative to the machine body 30 of the boom 43 is referred to as a pair unit angle theta _b. Pairs machine angle theta _b in the case of the boom 43 and the storage state is 0.

Further, the ground angle θ _g of the boom 43 ′ when the hoisting cylinder 45 is at the stroke end is referred to as a stroke end ground angle Θ _g . The machine angle θ _b of the boom 43 ′ when the hoisting cylinder 45 is the stroke end is referred to as a stroke end machine angle θ _b . The stroke end ground angle Θ _g and the stroke end versus machine angle Θ _b are respectively the extension side stroke end of the hoisting cylinder 45 (the stroke end on the elevation side of the boom 43) and the contraction side stroke end (on the side of the collapse of the boom 43). Two types of stroke end) are included.

The load-type truck crane M is provided with an overload prevention device in order to ensure stability. In general, the overload prevention device, the length detector for detecting the length of the boom 43, and ground angle detector for detecting a ground angle theta _g of the boom 43, the rotation angle detector for detecting the turning angle of the boom 43 And a undulation reaction force detector for detecting a load acting on the undulation cylinder 45. The limit of the overturning moment from the length of the boom 43 detected by the length detector, the ground angle θ _g of the boom 43 detected by the ground angle detector, and the turning angle of the boom 43 detected by the turning angle detector. When the moment acting on the boom 43 detected by the undulation reaction force detector is about to exceed the limit value of the overturning moment, the boom operation is restricted or a warning is issued. The truck crane M is prevented from falling.

  The load-type truck crane M is provided with a jack-up state detector as a safety device. The jack-up state detector is a detector that detects that the jack-up of the outrigger 44 has been completed. By allowing the crane work only in a state where the jack-up is completed, forgetting the jack-up is prevented, and the stability of the load-type truck crane M is ensured.

  Further, the load-type truck crane M is provided with a boom retracted state detector as a safety device. The boom retracted state detector is a detector that detects that the boom 43 is retracted. By allowing the general-purpose truck 30 to travel only when the boom 43 is in the retracted state, forgetting to store the boom 43 is prevented and accidents during traveling are prevented.

(First embodiment)
Next, the stroke end detection device A according to the first embodiment of the present invention will be described.
As shown in FIG. 1, the stroke end detection device A includes a ground angle detector 11, a jack-up state detector 12, and a stroke end determination means 20.

The ground angle detector 11 is a detector that detects the ground angle θ _g of the boom 43. The ground angle detector 11 is composed of, for example, a rotary potentiometer. As described above, since the ground angle detector 11 is used in an overload prevention device, one ground angle detector 11 may be used in combination with the stroke end detection device A and the overload prevention device, and a new detector is provided. There is no need.

  The jack-up state detector 12 is a detector that detects that the jack-up of the outrigger 44 has been completed. The jack-up state detector 12 includes, for example, a hydraulic sensor provided in an oil passage connected to the oil chamber on the extension operation side of the outrigger jack 44b, and detects that the jack-up is completed from the hydraulic pressure measured by the hydraulic sensor. It is comprised so that it may do. As described above, since the jack-up state detector 12 is used as a safety device, one jack-up state detector 12 may be used in combination with the stroke end detection device A and the safety device, and it is not necessary to provide a new detector. Absent.

The stroke end determination means 20 is constituted by a CPU, a memory, and the like, and the detection values of the ground angle detector 11 and the jack-up state detector 12 are input. Further, the stroke end-to-machine angle theta _b is stored in advance in the stroke end determination means 20. Incidentally, the stroke end-to-machine angle theta _b is determined from the structure of the loading type truck cranes M. Further, as the stroke end-to-machine angle theta _b, it may be set pairs machine angle theta _b when derricking cylinder 45 is positively stroke end, provided with a margin before reaching its pair machine angle theta _b A value may be set.

  The stroke end determination means 20 receives the detection values of the ground angle detector 11 and the jack-up state detector 12 as input, determines whether or not the hoisting cylinder 45 is at the stroke end, and outputs the result. In FIG. 1, symbol X is an overload prevention device, an indicator lamp, etc., and operates based on the output of the stroke end determination means 20.

The stroke end determination means 20 determines the stroke end of the hoisting cylinder 45 in the following procedure.
As shown in FIG. 2, the stroke end determination means 20 performs a stroke end determination process (step S200) after performing a stroke end ground angle calculation process (step S100) as a pre-process. The stroke end determination process (step S200) is repeatedly performed to determine at any time whether or not the undulating cylinder 45 is at the stroke end. The stroke end determination means 20 is turned on and starts processing when the power take-off device is switched to a power take-off state (a state in which engine power is supplied to the small crane 40), for example. For example, when the power take-off state of the power take-off device is canceled, the power is turned off, and the process ends.

Next, details of the stroke end ground angle calculation process (step S100) will be described.
As shown in FIG. 3, first, the stroke end determination means 20 determines whether or not the jackup state detector 12 detects that the jacking up of the outrigger 44 has been completed (step S111). Step S111 is repeated until the jackup is completed, and the process waits until the jackup is completed.

When the jack-up is completed, the stroke end determination unit 20 acquires the ground angle θ _g detected by the ground angle detector 11 and sets the ground angle θ _g as the aircraft inclination angle α (step S112). That is, the ground angle θ _g detected by the ground angle detector 11 when the jack-up state detector 12 detects the completion of the jack-up is defined as the body inclination angle α. Boom 43 immediately jack up completed vs. machine angle theta _b for a storage state is zero. Therefore, the ground angle θ _g of the boom 43 is equal to the aircraft inclination angle α, and the aircraft inclination angle α can be obtained from the ground angle θ _g (see FIG. 17).

Next, the stroke end determination means 20 obtains the stroke end ground angle Θ _g from the body inclination angle α and the stroke end versus machine angle Θ _b stored in advance (step S113).

Specifically, as shown in formula 1 below, calculates the stroke end ground angle theta _g by adding the body tilt angle α in the stroke end-to-machine angle theta _b. Note that if the aircraft inclination angle α is added to the stroke end angle Θ _b at the extension side stroke end, the stroke end angle Θ _{g at the} extension side stroke end is obtained, and the stroke end angle Θ _{b at the} contraction side stroke end is obtained. Is added to the vehicle body tilt angle α, the stroke end ground angle Θ _{g of the} contraction side stroke end can be obtained.

Incidentally, in advance stores a plurality of stroke end ground angle theta _g per body inclination angle alpha, be configured to obtain the stroke end ground angle theta _g corresponding to the aircraft angle of inclination alpha obtained in step S112 Also good.

Next, details of the stroke end determination process (step S200) will be described.
As shown in FIG. 4, first, the stroke end determination means 20 acquires the current ground angle θ _g detected by the ground angle detector 11 (step S211).

Next, the stroke end ground angle Θ _g obtained in the stroke end ground angle calculation process (step S100) is compared with the current ground angle θ _g (step S212). Current ground angle theta _g is extended side stroke end of the stroke end ground angle theta _g or more, or in the case of the following stroke end ground angle theta _g of contraction-side stroke end, the determined result of the determination that the stroke end Output (step S213). On the other hand, if the current ground angle θ _g is less than the stroke end ground angle Θ _{g at the} extension side stroke end and larger than the stroke end ground angle Θ _{g at the} contraction side stroke end, it is determined that it is not the stroke end and the stroke end determination is made. The process (step S200) ends. Even when it is determined that the stroke end is not reached, the determination result may be output.

  By repeatedly performing the stroke end determination process (step S200) (see FIG. 2), it is determined at any time whether the hoisting cylinder 45 is at the stroke end during crane work.

When the output of the stroke end detection device A is input to the overload prevention device X, the overload prevention device X is based on the input from the stroke end detection device A, and when the stroke end is detected, the undulation reaction force detector is detected. It operates so as not to use the detected value. The overload prevention device X may be changed in operation only in the case of the extension side stroke end. Therefore, the stroke end ground angle Θ _g and the stroke end versus machine angle Θ _b may be configured to consider only the case of the extension side stroke end. In this case, in step S212, the determination that the stroke end when the current ground angle theta _g is not less than the stroke end ground angle theta _g of extension side stroke end, the stroke end ground angle theta less than _g of the expansion side stroke end In this case, it is determined that it is not the stroke end.

  When the output of the stroke end detection device A is input to the indicator lamp X, the indicator lamp X is turned on when it is at the stroke end, based on the input from the stroke end detection device A, and warns the worker. To emit.

As described above, the stroke end detection device A has the stroke end ground angle Θ _g obtained based on the stroke end angle Θ _b stored in advance and the detection value of the ground angle detector 11, and the current ground. by comparing the angle theta _g, since derricking cylinder 45 to determine whether the stroke end can be detected correctly even stroke end by universal track 30 is tilted with respect to the horizontal plane G.

  Further, since the ground angle detector 11 used in the overload prevention device can be used, it is not necessary to provide a new detector, and the stroke end of the undulation cylinder 45 can be detected with an inexpensive configuration.

(Second Embodiment)
Next, a stroke end detection device B according to a second embodiment of the present invention will be described.
As shown in FIG. 5, the stroke end detection device B includes a turning angle detector 13 that detects the turning angle φ of the boom 43 in addition to the ground angle detector 11 and the jack-up state detector 12. Detection values of the ground angle detector 11, the jack-up state detector 12, and the turning angle detector 13 are input to the stroke end determination means 20. In this specification, the turning angle φ when the boom 43 is in the retracted state is set to zero.

  Also in this embodiment, as shown in FIG. 2, the stroke end determination means 20 repeatedly performs the stroke end determination process (step S200) after performing the stroke end ground angle calculation process (step S100) as the pre-processing. .

The basic flow of the stroke end ground angle calculation process (step S100) of this embodiment is the same as that of the first embodiment (see FIG. 3). However, the processing in step S113 is different. In the present embodiment, in step S113, the stroke end determination means 20 determines the stroke end ground angle depending on the turning angle φ of the boom 43 from the aircraft inclination angle α and the stroke end-to-machine angle Θ _b stored in advance. seek Θ _g. Here, “the stroke end ground angle Θ _g depending on the turning angle φ” means that the stroke end ground angle Θ _g is a function of the turning angle φ, or that the stroke end ground angle Θ _g is a plurality of turning angles φ. This is a concept including a case of a combination of values.

Specifically, as shown in the following equation 2, the stroke end ground angle Θ _g is obtained as a function of the turning angle φ from the stroke end versus machine angle Θ _b and the body inclination angle α. If the stroke end-to-machine angle Θ _b of the extension side stroke end is substituted into Equation 2, the stroke end-to-ground angle Θ _g (φ) of the extension side stroke end can be obtained. If the machine angle Θ _b is substituted, the stroke end ground angle Θ _g (φ) of the contraction side stroke end can be obtained.

Equation 2 is derived as follows.
First, the aircraft inclination angle α is obtained as a function of the orientation φ of the aircraft 30. Here, the direction φ of the airframe 30 is the same as the turning angle φ of the boom 43. The direction φ is set to 0 when the boom 43 is in the retracted state. Further, it is assumed that the direction of inclination of the fuselage 30 is the same as the direction of the boom 43 in the retracted state.

As shown in FIG. 18, the aircraft inclination angle α obtained in step S112 is the aircraft inclination angle α in the direction φ = 0 because it is the ground angle θ _g of the boom 43 in the retracted state. If the line segment OA is a line segment of unit length e extending from the origin O to the direction φ = 0 along the inclined plane I of the airframe 30, the length of the perpendicular from the point A to the horizontal plane G (xy plane) passing through the origin O The length h ₁ is expressed by Equation 3.

If a line segment of unit length e extending from the origin O to the azimuth φ is a line segment OB, and the intersection of the perpendicular line from the point B to the line segment OA and the line segment OA is a point C, the length l of the line segment OC is It is represented by 4. From Equation 3 and Equation 4, the length h ₂ of the perpendicular from the point C to the horizontal plane G is expressed by Equation 5.

Since the length of the perpendicular line from the point B to the horizontal plane G is equal to the length h ₂ of the perpendicular line from the point C to the horizontal plane G, the aircraft inclination angle α (φ) in the azimuth φ is expressed by Equation 6. By substituting α (φ) obtained in Equation 6 into α in Equation 1, Equation 2 is obtained.

Instead of obtaining the stroke end ground angle Θ _g as a function of the turning angle φ, the stroke end ground angle Θ _g for each of the plurality of aircraft inclination angles α and turning angles φ is stored in advance and obtained in step S112. the stroke end ground angle theta _g corresponding to the aircraft angle of inclination α that is, may be configured to obtain a combination of values for a plurality of rotation angle phi.

Next, details of the stroke end determination process (step S200) will be described.
As shown in FIG. 6, first, the stroke end determination means 20 acquires the current ground angle θ _g detected by the ground angle detector 11 (step S221), and the current ground angle detected by the turning angle detector 13. The turning angle φ is acquired (step S222).

Next, the current turning angle φ is substituted into the stroke end ground angle Θ _g (φ) obtained in the stroke end ground angle calculation process (step S100), and the stroke end ground angle Θ _g (φ at the current turning angle φ is _calculated. ) Is obtained (step S223).

When the stroke end ground angle Θ _g for each of a plurality of aircraft inclination angles α and turning angles φ is stored in advance, the stroke for each of the plurality of turning angles φ acquired in the stroke end ground angle calculation process (step S100). from end ground angle theta _g, it obtains the stroke end ground angle theta _g corresponding to the current rotation angle phi (step S223).

Next, the stroke end ground angle Θ _g (φ) is compared with the current ground angle θ _g (step S224). Current ground angle theta _g is, the stroke of the extension-side stroke end end ground angle Θ _g (φ) or more, or when the stroke end ground angle theta _g (phi) less shrinkage side stroke end, if it is stroke end Judgment is made and the judgment result is output (step S225). On the other hand, when the current ground angle θ _g is less than the stroke end ground angle Θ _g (φ) at the extension side stroke end and larger than the stroke end ground angle Θ _g (φ) at the contraction side stroke end, it is not a stroke end. And the stroke end determination process (step S200) ends.

If only the extension side stroke end is considered, in step S224, if the current ground angle θ _g is greater than or equal to the stroke end ground angle Θ _g (φ) of the extension side stroke end, it is determined that the stroke end is reached. If it is less than the stroke end ground angle Θ _g (φ) at the extension side stroke end, it is determined that it is not the stroke end.

  By repeatedly performing the stroke end determination process (step S200) (see FIG. 2), it is determined at any time whether the hoisting cylinder 45 is at the stroke end during crane work.

As described above, the stroke end detection device B according to the present embodiment compares the ground angle θ _g with the stroke end ground angle Θ _g (φ) in consideration of the turning angle φ of the boom 43, so that the jack-up is completed. Even when the boom 43 is turned from the above state, the stroke end of the hoisting cylinder 45 can be normally detected.

(Third embodiment)
In the second embodiment, it is assumed that the inclination direction of the body 30 and the direction of the boom 43 in the retracted state are the same. In the case of the load-type truck crane M, the inclination direction of the fuselage 30 is mainly the front-rear direction, and the boom 43 is stored in a state of being swung forward or backward. However, strictly speaking, the airframe 30 may also tilt in the left-right direction, and in this case, the tilting direction of the airframe 30 and the direction of the boom 43 in the retracted state are not the same. Further, when there are four outriggers such as a large mobile crane, the inclination direction can be any direction. The stroke end detection device C according to the third embodiment of the present invention is a form that takes into consideration the case where the inclination direction of the body 30 and the direction of the boom 43 in the retracted state are not the same.

  The stroke end detection device C of the present embodiment is provided with a ground angle detector 11, a jack-up state detector 12, and a turning angle detector 13, like the stroke end detection device B of the second embodiment. Is input to the stroke end determination means 20 (see FIG. 5).

  Also in this embodiment, as shown in FIG. 2, the stroke end determination means 20 repeatedly performs the stroke end determination process (step S200) after performing the stroke end ground angle calculation process (step S100) as the pre-processing. .

Next, details of the stroke end ground angle calculation process (step S100) will be described.
As shown in FIG. 7, first, the stroke end determination means 20 determines whether or not the jackup state detector 12 detects that the jacking up of the outrigger 44 has been completed (step S131). Step S131 is repeated until the jackup is completed, and the process waits until the jackup is completed.

When the jack-up is completed, the stroke end determination means 20 acquires the ground angle θ _g detected by the ground angle detector 11, and uses the ground angle θ _g as the direction φ = 0 (turning angle φ = 0). The aircraft inclination angle α _{0 at} is set to (step S132).

  Next, the stroke end determination means 20 turns the boom 43 by a predetermined turning angle φ (step S133). Here, the boom 43 may be automatically turned by an instruction from the stroke end determination means 20, or the boom 43 is turned by an operation of the worker by notifying the worker by voice or display. You may comprise.

After the boom 43 turns, the ground angle θ _g detected by the ground angle detector 11 is acquired, and the ground angle θ _g is set as the aircraft inclination angle α _φ in the direction φ (turning angle φ) (step S134). From the above, the ground angles (airframe inclination angles α ₀ , α _φ ) in the two directions (0, φ) when jack-up is completed are obtained.

Next, the stroke end determination means 20 determines the aircraft inclination direction β and the aircraft inclination angle α in the aircraft inclination direction β from the ground angles (aircraft inclination angles α ₀ , α _φ ) in these two directions (0, φ). Obtain (step S135).

Specifically, the airframe inclination angle α and the airframe inclination direction β are obtained from Equation 7 below.

In addition, Formula 7 is calculated | required as follows.
As shown in FIG. 19, when a unit vector extending from the origin O to the direction φ = 0 along the inclined plane I of the airframe 30 is a vector A, an angle formed by the vector A and a horizontal plane G (xy plane) passing through the origin O Is the aircraft inclination angle α ₀ in the direction φ = 0. Further, if a unit vector extending from the origin O to the azimuth φ along the inclined plane I is a vector B, an angle formed by the vector B and a horizontal plane G (xy plane) passing through the origin O is an aircraft inclination angle α _φ in the azimuth φ. It is. Therefore, when the vector A and the vector B are expressed by orthogonal coordinates, they are as follows.

The normal vector N of the inclined surface I is obtained by the outer product of the vector A and the vector B, and is as shown in Equation 9.

  The aircraft tilt direction β is equal to the angle formed by the projection vector of the normal vector N onto the horizontal plane G and the x axis, and the aircraft tilt angle α in the aircraft tilt direction β is equal to the angle formed by the normal vector N and the z axis. From this, the equation 7 is derived.

Then, the stroke end determination means 20, and the body tilt angle alpha, the vehicle body tilt angle direction beta, and a stroke end pairs machine angle theta _b stored in advance stroke end ground angle that depends on the turning angle φ of the boom 43 seek Θ _g (step S136).

Specifically, as shown in the following formula 10, the stroke end ground angle Θ _g is obtained as a variable of the turning angle φ from the stroke end air angle Θ _b , the airframe inclination angle α, and the airframe inclination direction β. Incidentally, by substituting the stroke-end pair machine angle theta _b extension side stroke end to the number 10, Motomari extension-side stroke end of the stroke end ground angle theta _g (phi) is the number 10 contraction side stroke end of the stroke end pairs If the machine angle Θ _b is substituted, the stroke end ground angle Θ _g (φ) of the contraction side stroke end can be obtained.

Instead of obtaining the stroke end ground angle Θ _g as a function of the turning angle φ, the stroke end ground angle Θ _g for each of the plurality of aircraft inclination angles α, the aircraft inclination direction β, and the turning angle φ is stored in advance. Alternatively, the stroke end ground angle Θ _g corresponding to the airframe inclination angle α and the airframe inclination direction β obtained in step S135 may be acquired as a combination of values for a plurality of turning angles φ.

  Since the stroke end determination process (step S200) of this embodiment is the same as that of the second embodiment, description thereof is omitted (see FIG. 6).

As described above, the stroke end detection device C according to the present embodiment obtains the stroke end ground angle Θ _g in consideration of the airframe inclination direction β, and therefore the direction of the boom 43 and the airframe inclination direction β in the state where the jack-up is completed. Even if they deviate, the stroke end of the undulating cylinder 45 can be detected normally.

In the present embodiment, the aircraft inclination angle α and the aircraft inclination direction β are determined based on the aircraft inclination angles α ₀ and α _φ in two directions. However, the aircraft inclination angle α is determined based on the aircraft inclination angles in three or more directions. And the machine body tilt direction β may be obtained. Thus, by calculating based on the multidirectional aircraft inclination angle, the aircraft inclination angle α and the aircraft inclination direction β can be obtained with high accuracy.

(Fourth embodiment)
In the stroke end ground angle calculation process (step S100) of the above embodiment, it is assumed that the boom 43 is in the retracted state when the stroke end detection device starts the process (power ON). Normally, the loadable truck crane M travels to the work site with the boom 43 in the retracted state, switches the power take-off device to the power take-off state (the stroke end detection device is turned on), and starts the crane operation. Then, after the crane work is finished, the boom 43 is returned to the retracted state. Therefore, the boom 43 when the stroke end detection device starts processing is normally in the retracted state.

However, for example, there is a case where the worker stops the engine without returning the boom 43 to the retracted state and stops the stroke end detection device, for example, during a break during crane work. In this case, when starting the operation again, if the engine is started and the stroke end detection device is activated, the boom 43 is not in the retracted state when the stroke end detection device starts processing. it is impossible to determine the correct stroke end ground angle theta _g in step S100). The stroke end detection device D according to the fourth embodiment of the present invention is an embodiment in which such a problem is solved.

  As shown in FIG. 8, the stroke end detection device D according to this embodiment includes a boom retracted state detector 14 in addition to the ground angle detector 11, the jack-up state detector 12, and the turning angle detector 13. . Detection values of the ground angle detector 11, the jack-up state detector 12, the turning angle detector 13, and the boom retracted state detector 14 are input to the stroke end determination means 20.

  The boom storage state detector 14 is a detector that detects that the boom 43 is in the storage state. The boom retracted state detector 14 is composed of, for example, a limit switch provided at the boom rest. As described above, since the boom retracted state detector 14 is used as a safety device, one boom retracted state detector 14 may be used in combination with the stroke end detector D and the safety device, and a new detector needs to be provided. Absent.

  Also in this embodiment, as shown in FIG. 2, the stroke end determination means 20 repeatedly performs the stroke end determination process (step S200) after performing the stroke end ground angle calculation process (step S100) as the pre-processing. .

Next, details of the stroke end ground angle calculation process (step S100) will be described.
As shown in FIG. 9, the stroke end determination means 20 first determines whether or not the jack-up state detector 12 has detected that the jack-up of the outrigger 44 has been completed (step S141). Step S141 is repeated until the jackup is completed, and the process waits until the jackup is completed.

  When the jackup is completed, the stroke end determination means 20 determines whether or not the boom retracted state detector 14 has detected that the boom 43 is retracted (step S142).

When the boom storage state detector 14 detects that the boom 43 is in the storage state, the same processing as in the first to third embodiments is performed to determine the stroke end ground angle Θ _g (steps S143 to S144). . Then, it stores the stroke end ground angle theta _g determined in the storage device (step S145).

When the boom retracted state detector 14 does not detect that the boom 43 is retracted, that is, when the boom 43 is not retracted, the stroke stored in the storage device is not _calculated without determining the stroke end ground angle Θg. It acquires end ground angle theta _g (step S146). Thereby, when the boom 43 is not in the retracted state when the stroke end detection device D starts processing, the stroke end ground angle Θ _g obtained last time can be used.

In the stroke end determination process (step S200), the stroke end ground angle theta _g or obtained in step S144, by using the stroke end ground angle theta _g obtained from the storage device in step S146, it is determined stroke end. Since the details are the same as those in the first to third embodiments, the description thereof will be omitted.

As described above, since the stroke end detection device D of the present embodiment acquires the stored stroke end ground angle Θ _g when the boom 43 is not in the retracted state, the work is completed without storing the boom 43. , even if you resume work, it is possible to correct the value of the stroke end ground angle Θ _g.

(Fifth embodiment)
In the above embodiment, by comparing the stroke end ground angle theta _g and the current ground angle theta _g, although it is determined whether the stroke end, the stroke end-to-machine angle theta _b and the current-to-machine The angle θ _b may be compared to determine whether or not it is the stroke end. Hereinafter, an embodiment based on the latter determination method will be described.

Next, a stroke end detection device E according to a fifth embodiment of the invention will be described.
Similar to the stroke end detection device A of the first embodiment, the trolley end detection device E of the present embodiment includes a ground angle detector 11 and a jack-up state detector 12, and these detected values are the stroke end. It is input to the judging means 20 (see FIG. 1).

The stroke end determination means 20 determines the stroke end of the hoisting cylinder 45 in the following procedure.
As shown in FIG. 10, the stroke end determination means 20 performs a stroke end determination process (step S400) after performing a body inclination angle calculation process (step S300) as a pre-process. The stroke end determination process (step S400) is repeatedly performed to determine at any time whether or not the undulation cylinder 45 is at the stroke end.

Next, details of the aircraft tilt angle calculation process (step S300) will be described.
As shown in FIG. 11, the stroke end determination means 20 first determines whether or not the jack-up state detector 12 detects that the jack-up of the outrigger 44 has been completed (step S351). Step S351 is repeated until the jackup is completed, and the process waits until the jackup is completed.

When the jack-up is completed, the stroke end determination means 20 acquires the ground angle θ _g detected by the ground angle detector 11 and sets the ground angle θ _g as the aircraft inclination angle α (step S352). That is, the ground angle θ _g detected by the ground angle detector 11 when the jack-up state detector 12 detects the completion of the jack-up is defined as the body inclination angle α.

Next, details of the stroke end determination process (step S400) will be described.
As shown in FIG. 12, first, the stroke end determination means 20 acquires the current ground angle θ _g detected by the ground angle detector 11 (step S451).

Next, the stroke end determination means 20 obtains the aircraft angle θ _b of the boom 43 from the aircraft inclination angle α obtained in the aircraft inclination angle calculation process (step S300) and the current ground angle θ _g (step). S452). Specifically, as shown in the following equation 11, the aircraft angle θ _b is calculated by subtracting the aircraft inclination angle α from the current ground angle θ _g .

Next, the stroke end machine angle Θ _b stored in advance is compared with the current machine angle θ _b obtained in step S452 (step S453). Current vs. machine angle theta _b is extended side stroke end of the stroke end-to-machine angle theta _b or more, or in the case of the following stroke end pairs machine angle theta _b contraction side stroke end, it is determined that the stroke end thereof The determination result is output (step S454). On the other hand, if the current machine angle θ _b is less than the stroke end machine angle Θ _{b at} the extension side stroke end and greater than the stroke end machine angle Θ _{b at the} contraction side stroke end, it is determined that it is not the stroke end. The stroke end determination process (step S400) ends.

When only the extension side stroke end is considered, in step S453, if the current machine angle θ _b is greater than or equal to the stroke end machine angle Θ _{b of the} extension side stroke end, it is determined that it is the stroke end. , if less than the stroke end-to-machine angle theta _b extension side stroke end is determined not to be the stroke end.

  By repeatedly performing the stroke end determination process (step S400) (see FIG. 10), it is determined at any time whether the hoisting cylinder 45 is at the stroke end during the crane operation.

As described above, the stroke end detection device E compares the machine angle θ _b calculated based on the detection value of the ground angle detector 11 with the stroke end machine angle Θ _b stored in advance, Since it is determined whether the hoisting cylinder 45 is at the stroke end, the stroke end can be detected normally even if the general-purpose truck 30 is inclined with respect to the horizontal plane G.

  Further, since the ground angle detector 11 used in the overload prevention device can be used, it is not necessary to provide a new detector, and the stroke end of the undulation cylinder 45 can be detected with an inexpensive configuration.

(Sixth embodiment)
Next, a stroke end detection device F according to a sixth embodiment of the present invention will be described.
Like the stroke end detection device B of the second embodiment, the stroke end detection device F of the present embodiment includes a ground angle detector 11, a jack-up state detector 12, and a turning angle detector 13. Is input to the stroke end determination means 20 (see FIG. 5).

  Also in the present embodiment, as shown in FIG. 10, the stroke end determination means 20 repeatedly performs the stroke end determination process (step S400) after performing the body inclination angle calculation process (step S300) as the pre-processing.

  The airframe tilt angle calculation process (step S300) of the present embodiment is the same as that of the fifth embodiment, and a description thereof will be omitted (see FIG. 11).

Next, details of the stroke end determination process (step S400) will be described.
As shown in FIG. 13, first, the stroke end determination means 20 acquires the current ground angle θ _g detected by the ground angle detector 11 (step S461), and the current ground angle detected by the turning angle detector 13. The turning angle φ is acquired (step S462).

Next, the current aircraft angle θ _b is determined from the aircraft tilt angle α determined in the aircraft tilt angle calculation process (step S300), the current ground angle θ _g, and the current turning angle φ (step S463). ). Specifically, the current machine angle θ _b is obtained from the following equation (12). Equation 12 is derived by substituting α (φ) obtained in Equation 6 into α in Equation 11.

Instead of calculating the machine angle θ _b from the function shown in Equation 12, the machine angle θ _b for each of a plurality of machine body inclination angles α and turning angles φ is stored in advance, and Steps S461 and S462 are performed. The ground angle θ _g and the machine angle θ _b corresponding to the turning angle φ may be acquired.

Next, the stroke end machine angle Θ _b stored in advance is compared with the current machine angle θ _b obtained in step S463 (step S464). Current vs. machine angle theta _b is extended side stroke end of the stroke end-to-machine angle theta _b or more, or in the case of the following stroke end pairs machine angle theta _b contraction side stroke end, it is determined that the stroke end thereof The determination result is output (step S465). On the other hand, if the current machine angle θ _b is less than the stroke end machine angle Θ _{b at} the extension side stroke end and greater than the stroke end machine angle Θ _{b at the} contraction side stroke end, it is determined that it is not the stroke end. The stroke end determination process (step S400) ends.

When only the extension side stroke end is considered, in step S464, if the current machine angle θ _b is greater than or equal to the stroke end machine angle Θ _{b of the} extension side stroke end, it is determined that the stroke end is reached. , if less than the stroke end-to-machine angle theta _b extension side stroke end is determined not to be the stroke end.

  By repeatedly performing the stroke end determination process (step S400) (see FIG. 10), it is determined at any time whether the hoisting cylinder 45 is at the stroke end during the crane operation.

As described above, the stroke end detection device F according to the present embodiment obtains the machine angle θ _b in consideration of the turning angle φ of the boom 43. Therefore, when the boom 43 is turned from the state where the jack-up is completed. In addition, the stroke end of the undulating cylinder 45 can be detected normally.

(Seventh embodiment)
Next, a stroke end detection device G according to a seventh embodiment of the present invention will be described.
Like the stroke end detection device B of the second embodiment, the stroke end detection device G of the present embodiment includes a ground angle detector 11, a jack-up state detector 12, and a turning angle detector 13. Is input to the stroke end determination means 20 (see FIG. 5).

  Also in the present embodiment, as shown in FIG. 10, the stroke end determination means 20 repeatedly performs the stroke end determination process (step S400) after performing the body inclination angle calculation process (step S300) as the pre-processing.

Next, details of the aircraft tilt angle calculation process (step S300) will be described.
As shown in FIG. 14, the stroke end determination means 20 first determines whether or not the jackup state detector 12 detects that the jacking up of the outrigger 44 has been completed (step S371). Step S371 is repeated until the jackup is completed, and the process waits until the jackup is completed.

When the jack-up is completed, the stroke end determination means 20 acquires the ground angle θ _g detected by the ground angle detector 11, and uses the ground angle θ _g as the direction φ = 0 (turning angle φ = 0). The aircraft inclination angle α _{0 at} is set as step S372.

Next, the stroke end determination means 20 turns the boom 43 by a predetermined turning angle φ (step S373). After the boom 43 turns, the ground angle θ _g detected by the ground angle detector 11 is acquired, and the ground angle θ _g is set as the aircraft inclination angle α _φ in the direction φ (turning angle φ) (step S374). From the above, the ground angles (airframe inclination angles α ₀ , α _φ ) in the two directions (0, φ) when jack-up is completed are obtained.

Next, the stroke end determination means 20 calculates the airframe tilt direction β and the airframe in the airframe tilt direction β from the ground angles (aircraft tilt angles α ₀ , α _φ ) in these two directions (0, φ) from the above equation (7). The inclination angle α is obtained (step S375).

Next, details of the stroke end determination process (step S400) will be described.
The basic flow of the stroke end determination process (step S400) of this embodiment is the same as that of the sixth embodiment (see FIG. 13). However, the machine angle calculation process in step S463 is different.

In step S463, the current aircraft angle θ _b is determined from the aircraft tilt angle α and the aircraft tilt direction β determined in the aircraft tilt angle calculation process (step S300), and the current ground angle θ _g and turning angle φ. . Specifically, the current machine angle θ _b is obtained from the following equation (13).

As described above, the stroke end detection device G according to the present embodiment obtains the machine angle θ _b in consideration of the machine body tilt direction β, so the direction of the boom 43 and the machine body tilt direction β in the state where the jack-up is completed are determined. Even if the deviation occurs, the stroke end of the undulating cylinder 45 can be detected normally.

(Eighth embodiment)
Next, a stroke end detection device H according to an eighth embodiment of the invention will be described.
As with the stroke end detection device D of the fourth embodiment, the stroke end detection device H of this embodiment is a ground angle detector 11, a jack-up state detector 12, a turning angle detector 13, and a boom retracted state detector. 14 and their detected values are input to the stroke end determination means 20 (see FIG. 8).

  Also in the present embodiment, as shown in FIG. 10, the stroke end determination means 20 repeatedly performs the stroke end determination process (step S400) after performing the body inclination angle calculation process (step S300) as the pre-processing.

Next, details of the aircraft tilt angle calculation process (step S300) will be described.
As shown in FIG. 15, the stroke end determination means 20 first determines whether or not the jack-up state detector 12 has detected that the jack-up of the outrigger 44 has been completed (step S381). Step S381 is repeated until jackup is completed, and the process waits until jackup is completed.

  When the jackup is completed, the stroke end determination means 20 determines whether or not the boom retracted state detector 14 has detected that the boom 43 is retracted (step S382).

  When the boom storage state detector 14 detects that the boom 43 is in the storage state, the same processing as in the fifth to seventh embodiments is performed to obtain the aircraft inclination angle α (step S383). Then, the obtained machine body inclination angle α is stored in the storage device (step S384). In the case where the same processing as in the seventh embodiment is performed, the obtained aircraft inclination angle α and aircraft inclination direction β are stored in the storage device.

  When the boom storage state detector 14 does not detect that the boom 43 is in the storage state, that is, when the boom 43 is not in the storage state, the body inclination angle α stored in the storage device is not obtained without obtaining the body inclination angle α. α is acquired (step S385). Thereby, when the boom 43 is not in the retracted state when the stroke end detection device H starts processing, the previously determined machine body inclination angle α can be used. In addition, when performing the same process as 7th Embodiment, the body inclination angle (alpha) and the body inclination direction (beta) memorize | stored in the memory | storage device are acquired.

  In the stroke end determination process (step S400), the airframe inclination angle α and / or the airframe inclination direction β obtained in step S383, or the airframe inclination angle α and / or the airframe inclination direction β obtained from the storage device in step S385 are used. Determine the stroke end. Since the details are the same as those in the fifth to seventh embodiments, description thereof will be omitted.

  As described above, the stroke end detection device H of the present embodiment acquires the stored aircraft inclination angle α and / or aircraft inclination direction β when the boom storage state detector 14 detects that it is not in the storage state. Even when the work is resumed after the work is finished without storing the boom 43, the machine body tilt angle α and / or the machine body tilt direction β can be set to correct values.

A to H Stroke end detection device M Loading type truck crane 11 Ground angle detector 12 Jackup state detector 13 Turning angle detector 14 Boom storage state detector 20 Stroke end determination means 30 General purpose truck 31 Driver's cab 32 Car bed 33 Vehicle frame 40 small crane 41 base 42 post 43 boom 44 outrigger 45 hoisting cylinder 46 hook

Claims (5)

An apparatus for detecting a stroke end of a hoisting cylinder in a work vehicle comprising an airframe, an outrigger provided on the airframe, a boom provided so as to be able to rise and fall with respect to the airframe, and a hoisting cylinder for hoisting the boom Because
A ground angle detector for detecting a ground angle which is an angle with respect to a horizontal plane of the boom;
A jack-up state detector for detecting the completion of jack-up of the outrigger;
The detection values of the ground angle detector and the jack-up state detector are input, and the stroke end-to-machine angle, which is the angle of the boom with respect to the body when the hoisting cylinder is at the stroke end, is stored in advance. A stroke end determining means,
The stroke end determination means includes
The ground angle when the jack-up state detector detects the aircraft inclination angle,
From the stroke end vs. machine angle and the aircraft inclination angle, a stroke end vs. ground angle which is an angle with respect to the horizontal plane of the boom when the hoisting cylinder is at the stroke end,
A stroke end detecting device for a hoisting cylinder, wherein the stroke end ground angle is compared with the current ground angle to determine whether or not the hoisting cylinder is a stroke end. A turning angle detector for detecting a turning angle of the boom;
The stroke end determination means includes
The detection value of the turning angle detector is input,
From the stroke end-to-machine angle and the airframe inclination angle, the stroke end-to-ground angle depending on the turning angle of the boom is determined,
2. The undulation cylinder according to claim 1, wherein the stroke end ground angle at the current turning angle is compared with the current ground angle to determine whether or not the undulation cylinder is a stroke end. 3. Stroke end detection device. The stroke end determination means includes
From the ground angle in at least two directions when the jack-up state detector detects, determine the aircraft inclination direction and the aircraft inclination angle in the aircraft inclination direction,
The stroke end detection of the hoisting cylinder according to claim 2, wherein the stroke end ground angle depending on the turning angle of the boom is obtained from the stroke end airframe angle, the airframe inclination angle, and the airframe inclination direction. apparatus. A boom retracted state detector for detecting that the boom is retracted;
The stroke end determination means includes
The detection value of the boom storage state detector is input,
If the boom retracted state detector detects the stroke end ground angle when the jackup state detector detects, the stroke end ground angle is stored, and if the boom retracted state detector does not detect, the stored stroke The end-to-ground angle is obtained, and the stroke end detection device for a hoisting cylinder according to claim 1, 2, or 3. An apparatus for detecting a stroke end of a hoisting cylinder in a work vehicle comprising an airframe, an outrigger provided on the airframe, a boom provided so as to be able to rise and fall with respect to the airframe, and a hoisting cylinder for hoisting the boom Because
A ground angle detector for detecting a ground angle which is an angle with respect to a horizontal plane of the boom;
A jack-up state detector for detecting the completion of jack-up of the outrigger;
The detection values of the ground angle detector and the jack-up state detector are input, and the stroke end-to-machine angle, which is the angle of the boom with respect to the body when the hoisting cylinder is at the stroke end, is stored in advance. A stroke end determining means,
The stroke end determination means includes
The ground angle when the jack-up state detector detects the aircraft inclination angle,
From the aircraft inclination angle and the current ground angle, obtain an aircraft angle that is an angle of the boom with respect to the aircraft,
A stroke end detecting device for a hoisting cylinder, wherein the stroke end machine angle is compared with the machine angle to determine whether or not the hoisting cylinder is a stroke end.