Loading truck crane

Abstract

To provide a loading type truck crane capable of accurately obtaining a rated load in a side region.SOLUTION: Jacks 38a and 38b, which are respectively provided on right and left outside end parts of an outrigger device 33, and a control device 12 are provided on a loading type truck crane 10. When a boom 32 is rotated in one of right and left side regions, the control device 12 determines overturning lines LRS and LLS by utilizing a rotation angle θ obtained when a grounding reaction force signal of the other one of the right and left jacks 38a and 38b indicates the lowest value. Then, the control device 12 calculates overturning moment by utilizing the overturning lines LRS and LLS. This configuration makes it possible to obtain a rated load in the side region further accurately.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a loading truck crane, and more particularly to a loading truck crane provided with a crane device and an outrigger device between a driver's cab and a loading platform. [Background technology]

[0002] A loaded truck crane is a vehicle that has a crane device mounted on a truck with a loading platform. The crane device is mounted between the driver's cab and the loading platform. The crane device is operated by drawing power from a driving motor. When using a loaded truck crane, the boom of the crane device rotates around the base of the crane device and also extends and retracts. This action lifts the cargo and transports it.

[0003] In a loaded truck crane, an outrigger device is provided on the vehicle body to ensure stability of the vehicle body during crane operation. In most cases, one outrigger device is provided near the crane device. A hydraulic jack is provided on each of the left and right outer ends of the outrigger device. When performing crane operation, the user of the loaded truck crane works with the hydraulic jack extended from the vehicle body.

[0004] The rated load of a loaded truck crane is calculated from the capacity (stability performance) when there is no load on the platform and at the least stable turning position within the side area, and the capacity (crane strength performance) determined from the strength of the crane's structure. The graph in Figure 3 of Patent Document 1 is an example of a rated load calculated in this way, and Patent Document 1 discloses a configuration in which an alarm is issued or operation is stopped depending on the ratio of the lifting load to this rated load.

[0005] Patent Document 2 also discloses a method for calculating the rated load when using stability performance (stable rated lifting load in Patent Document 2). In Patent Document 2, the stable side moment and the overturning side moment are calculated based on either the left or right tipping baseline, and the rated load when using stability performance is calculated based on this. The tipping baseline in Patent Document 2 is defined as a line connecting the ground contact point of either the left or right outrigger jack and the ground contact point of the rear wheel located in the same direction. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 9-86873 [Patent Document 2] JP 2007-297169 A Summary of the Invention [Problem to be solved by the invention]

[0007] When calculating the rated load based on stability performance, there is a method disclosed in Patent Document 2, in which the calculation is based on the tipping baseline connecting the ground contact point of either the left or right outrigger jack and the ground contact point of the rear wheel located in the same direction. The calculation of the rated load based on the stability performance may be based on the overturning line defined below. In other words, in the plan view shown in FIG. 6, the center of each jack of the outrigger device 33 extended to the left and right outer limit positions (for example, the center of the right jack 38a) and the left and right center O of the rear axle provided between the left and right rear wheels 23 are aligned along the overturning line. T The line connecting and is the right overturn line L RT (Same as the fall baseline above). From this point on, the procedure is the same as in Patent Document 2. That is, in plan view, this right overturn line L RT From the boom 32 rotation center O C (In the following, the angle between this perpendicular line and the initial position of the boom of the loaded truck crane at the front of the vehicle is called the "conventional swing angle θ RTThe length of this perpendicular line is the right overturn line L RT From each point above to the boom rotation center O C Theoretically, the state where the boom is on this perpendicular line is considered to be the worst state in terms of stability. Taking this state into consideration, the tipping line L is defined. RT , L LT was used to calculate the overturning moment and to determine the rated load in the lateral area based on the stability performance. In other words, most of the calculations related to the overturning moment were carried out based on this overturning line.

[0008] However, since there are many types of vehicles used in loaded truck cranes, and the length of the wheelbase or the number of rear axles also varies widely, there is a problem that the tipping line defined only from the structure does not necessarily match the actual tipping line depending on the vehicle type. In other words, if it does not match the actual tipping line, the calculated tipping moment value does not match the actual value, and there is a problem that the rated load in the side area based on the stability performance cannot be accurately obtained. In view of the above circumstances, an object of the present invention is to provide a loaded truck crane that is capable of accurately calculating the rated load in the side area based on stability performance. [Means for solving the problem]

[0009] The loaded truck crane of the first invention is a loaded truck crane equipped with a crane device and an outrigger device between the driver's cab and the bed, and the loaded truck crane is equipped with jacks respectively provided on the left and right outer ends of the outrigger devices and a control device that receives the ground reaction signal of the jacks, and the control device is characterized in that when the rotation position of the boom constituting the crane device is in a side area, the control device defines the rotation angle at which the ground reaction signal of the other of the left and right jacks shows the lowest value when the boom is rotated in either the left or right side area as a first rotation angle, and defines a straight line that passes through the center of the jack located in either the left or right side area in a plan view and has an angle of 90° with the first rotation angle as a tipping line, and calculates the tipping moment using the tipping line. The loaded truck crane of the second invention is the same as the first invention, and is characterized in that the control device calculates the substantial center of the rear axle from the tipping line. Effect of the Invention

[0010] According to the first aspect of the present invention, the overturning line used to calculate the overturning moment is obtained from the ground reaction force of the jack, so that the rated load in the lateral area based on the stability performance can be calculated with higher accuracy. According to the second aspect of the present invention, by calculating the substantial rear axle center using the overturning line determined from the jack reaction force, the overturning line can be determined with high accuracy even if the extension width of the outrigger device is changed. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is an explanatory diagram of a tipping line of the loading truck crane according to the first embodiment of the present invention. [Diagram 2] FIG. 2 is a side view of the loading truck crane of FIG. 1. [Diagram 3] FIG. 2 is a hydraulic circuit diagram of the loading truck crane of FIG. 1. [Figure 4] FIG. 2 is a control circuit diagram of the loading truck crane of FIG. 1. [Diagram 5]FIG. 2 is an explanatory diagram of a working area of ​​the loading truck crane of FIG. 1. [Figure 6] FIG. 1 is an explanatory diagram of a tipping line of a conventional loading truck crane. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Next, an embodiment of the present invention will be described with reference to the drawings. However, the embodiment shown below is an example of a loaded truck crane for embodying the technical idea of ​​the present invention, and the present invention does not specify the loaded truck crane as described below. Note that the size or positional relationship of the members shown in each drawing may be exaggerated for clarity of explanation. In addition, in this specification, the descriptions of front, back, left, right, and front, back, left, and right are based on the user of the loaded truck crane when the user is seated in the driver's cab of the vehicle body.

[0013] First Embodiment (Loading truck crane 10) Fig. 2 shows a side view of the loaded truck crane 10 according to the first embodiment of the present invention. As shown in Fig. 2, the loaded truck crane 10 has a crane device 21 mounted on a vehicle frame 29 between a driver's cab 27 and a loading platform 28 of a general-purpose truck 20. The general-purpose truck 20 is provided with front wheels 22 symmetrically on the left and right. Furthermore, the general-purpose truck 20 is provided with rear wheels 23 symmetrically on the left and right.

[0014] As shown in Fig. 2, the crane apparatus 21 includes a base 30 fixed on the vehicle frame 29, a post 31 rotatably mounted on the base 30, and a boom 32 mounted on the upper end of the post 31 so as to be capable of being raised and lowered. In addition, the loaded truck crane 10 is equipped with an outrigger unit 33. The outrigger unit 33 is mounted on the base 30 and projects outward from the base 30 to the left and right. In other words, the crane apparatus 21 and the outrigger unit 33 are located between the driver's cab 27 and the loading platform 28 when viewed from the side. Hydraulic jacks 38a, 38b are provided on the left and right ends of the outrigger unit 33, respectively (see Fig. 5).

[0015] A winch is built into the post 31. A wire rope is led from this winch to the tip of the boom 32 and passed around a hook 34 via a pulley at the tip of the boom 32, so that the hook 34 is suspended from the tip of the boom 32.

[0016] The crane apparatus 21 is hydraulically driven by a hydraulic circuit 40 (see FIG. 3). A group of levers 35 for operating this hydraulic circuit 40 is provided on both the left and right sides of the base 30. In addition, a control device 12 is provided on the base 30 for electrically controlling the hydraulic circuit 40 and controlling the work vehicle.

[0017] (Hydraulic circuit 40) 3 shows a hydraulic circuit diagram of the loaded truck crane 10 according to this embodiment. As shown in FIG. 3, the hydraulic circuit 40 of the crane device 21 mainly includes a hydraulic valve unit 41, a hydraulic pump 43 that supplies hydraulic oil in a tank 42 to the hydraulic valve unit 41, a main oil passage 44 that connects the hydraulic pump 43 and the hydraulic valve unit 41, a return oil passage 45 that connects the hydraulic valve unit 41 and the tank 42, and a plurality of crane device actuators 46a-46d, two jacks 38a, 38b, and left and right extension actuators 38c, 38d of the outrigger device 33 for performing the extension and contraction operation of the boom 32, or the winding up and down of the winch, the raising and lowering operation of the boom 32, the turning operation of the boom 32, and the like. The crane device actuators 46a-46d, the jacks 38a, 38b, the right extension actuator 38c, and the left extension actuator 38d are connected to the hydraulic valve unit 41.

[0018] The hydraulic pump 43 is connected to the engine 36 of the utility truck 20 via a PTO (power take-off) device and is driven by the engine 36 .

[0019] The hydraulic valve unit 41 is provided with a boom extension / retraction control valve 47a, a winch control valve 47b, a boom hoist control valve 47c, a boom rotation control valve 47d, a right jack control valve 48a, a left jack control valve 48b, a right extension control valve 48c, and a left extension control valve 48d. The boom extension / retraction control valve 47a is connected to the boom extension / retraction actuator 46a, the winch control valve 47b to the winch hydraulic motor 46b, the boom hoist control valve 47c to the boom hoist actuator 46c, and the boom rotation control valve 47d to the boom rotation actuator 46d. In addition, the right side jack control valve 48a is connected to the right jack 38a located on the right side, the left side jack control valve 48b is connected to the left jack 38b located on the left side, the right extension control valve 48c is connected to the right extension actuator 38c, and the left extension control valve 48d is connected to the left extension actuator 38d.

[0020] A lever is attached to each of these switching control valves, and by manually operating the lever, the direction and flow rate of the hydraulic oil supplied from the hydraulic pump 43 can be switched.

[0021] The control device 12 is also connected to an ECU (engine control unit) of the engine 36, and is configured to be able to control at least the rotation speed of the engine 36. The control device 12 can control the rotation speed of the hydraulic pump 43 by controlling the rotation speed of the engine 36, and can adjust the discharge amount of the hydraulic pump 43.

[0022] (Control circuit) 4 shows a control circuit diagram of the loaded truck crane 10 according to this embodiment. The input side of the control device 12 is electrically connected to the boom length detector 15a, the boom rotation angle detector 15b, the boom hoisting angle detector 15c, the hoisting support force detector 15d, the right reaction force information detector 16a, the left reaction force information detector 16b, the right extension information detector 17a, and the left extension information detector 17b. The output side of the control device 12 is electrically connected to the alarm 14, the boom extension control valve 47a, the winch control valve 47b, the boom hoisting control valve 47c, the boom rotation control valve 47d, the right jack control valve 48a, the left jack control valve 48b, the right extension control valve 48c, and the left extension control valve 48d.

[0023] The boom length detector 15a detects the length of the boom 32 and is, for example, a cord payout length detector. The cord payout length detector detects the payout length of the measuring cord by detecting the amount of rotational displacement of the cord winder.

[0024] The boom rotation angle detector 15b detects the rotation angle of the boom 32 and is disposed on the base side of the post 31. For example, the boom rotation angle detector 15b is a potentiometer. A rotary encoder may be used instead of the potentiometer.

[0025] The boom hoist angle detector 15c detects the hoist angle of the boom 32 and is disposed on the base side of the boom 32. For example, the boom hoist angle detector 15c is a potentiometer. A rotary encoder may be used instead of the potentiometer.

[0026] The hoisting support force detector 15d is provided to detect the load suspended from the hook 34. In this embodiment, the hoisting support force detector 15d is a differential pressure gauge provided on a boom hoist cylinder. The differential pressure detected by the hoisting support force detector 15d is output to the control device 12.

[0027] The right reaction force information detector 16a is provided to detect a reaction force acting on the right jack 38a provided at the right outer end of the outrigger unit 33. The right reaction force information detector 16a may be, for example, a load cell using a strain gauge or a pressure gauge capable of detecting the pressure inside the jack, but is not limited to these. The left reaction force information detector 16b has the same configuration as the right reaction force information detector 16a.

[0028] The right extension information detector 17a is provided to detect that the right jack 38a of the outrigger unit 33 is in a predetermined extension position. The right extension information detector 17a can be, for example, a proximity switch, but is not limited to this. Also, the right extension information detector 17a can be, for example, a cord payout length detector. The left extension information detector 17b has the same configuration as the right extension information detector 17a.

[0029] The alarm 14 is for notifying the user of the loading truck crane 10 of a predetermined condition, for example, when the lifting load exceeds the rated load. In this embodiment, the alarm 14 is provided outside the operator's cab 27.

[0030] (work area) Fig. 5 is an explanatory diagram of the working area of ​​the loaded truck crane 10 according to this embodiment. Fig. 5 shows the loaded truck crane 10 in a plan view. In this embodiment, the loaded truck crane 10 is provided with an outrigger device 33 near the crane device 21, i.e., between the driver's cab 27 and the loading platform 28. The user of the loaded truck crane 10 lifts and lowers a load with the outrigger device 33 fully extended outward.

[0031] The weight of the load that the loaded truck crane 10 can safely load and unload varies depending on the angle in the horizontal plane of the boom 32 that constitutes the crane device 21, i.e., the rotation angle. Generally, the rated load of the loaded truck crane 10 is set for each of the following three areas: the rear area, the side area, and the front area. The rear area is the area (the side with the smaller angle formed by the two lines) between the rotation center Oc of the boom 32 and the left-right center of each of the two rear wheels 23 on the left and right (hereinafter sometimes referred to as the "right rear wheel center CR" and the "left rear wheel center CL") in a plan view.

[0032] The lateral area is the area between the line segment connecting the rotation center Oc of the boom 32 and the right rear wheel center CR and the line segment connecting the rotation center Oc of the boom 32 and the right jack 38a (the side where the angle formed by the two lines is smaller), or the area between the line segment connecting the rotation center Oc of the boom 32 and the left rear wheel center CL and the line segment connecting the rotation center Oc of the boom 32 and the left jack 38b (the side where the angle formed by the two lines is smaller).

[0033] The front area is the area between the line segment connecting the rotation center Oc of the boom 32 and the left and right jacks 38a, 38b (the side where the angle formed by the two line segments is smaller). In this embodiment, the three areas are defined as above, but the definition of the areas may differ depending on the configuration of the loaded truck crane 10. For example, in this embodiment, the working area is divided into three areas, the front area, the side area, and the rear area, but it may be divided into two areas, the front area and the side area. In addition, since the boundaries of each area are determined by a signal from the boom rotation angle detector 15b, they may be strictly different from the positions defined above. In addition, the front area is the side where the angle formed by the two line segments is smaller, but is not limited to this. For example, if the rotation center Oc of the boom 32 is located on the vehicle front side of the line segment connecting the left and right jacks 38a, 38b, the side where the angle formed by the two line segments is larger is the front area.

[0034] (Falling line L RS , L LS Determination method) FIG. 1 shows a tipping line L of a loading truck crane 10 according to a first embodiment of the present invention. RS , L LS The following is an explanatory diagram of the falling line L RS , L LS is used to calculate the tipping moment at least in the side region of the loading truck crane 10. The right tipping line L RS and left tipping line L LS The method of calculating is the same except for the left and right sides, so the right overturn line L RS The method of determining the above will be described.

[0035] The "overturning moment" is calculated from the length of the boom 32, the load of the suspended load, and other factors when an operator works with the loaded truck crane 10. Since it is calculated from the length of the boom 32, and other factors, it changes continuously depending on the work situation.

[0036] Right fall line L RS is determined when the crane device 21 and the outrigger device 33 are mounted on the general-purpose truck 20. RS Once the crane device 21 and the outrigger device 33 are mounted, they will not be changed thereafter.

[0037] With the crane device 21 and the outrigger device 33 mounted, the manufacturer of the loaded truck crane 10 extends the outrigger device 33 to the outermost position. Next, the manufacturer pushes the right jack 38a and the left jack 38b, which are provided on the left and right outer ends of the outrigger device 33, downward so that the left and right front wheels 22 of the loaded truck crane 10 are lifted up. With the front wheels 22 lifted up, the manufacturer moves the boom 32 constituting the crane device 21 so that the boom 32's rotation center O is raised. C Specifically, the initial position of the boom 32 is set at the center of rotation O in FIG. CThe left jack 38b is rotated 180 degrees clockwise from the initial position. During this rotation, the manufacturer detects the ground reaction force acting on the left jack 38b using the control device 12 and stores the detected value in the control device 12. The control device 12 then determines the rotation angle θ at which the ground reaction force is at its lowest value as the right first rotation angle θ. RS Store it as.

[0038] Then, the control device 12 determines the turning center O C Passing through, the first right turning angle θ RS The right overturning line L is a line that has an angle of 90 degrees with respect to the line having the right jack 38a and passes through the center of the right jack 38a. RS The control device 12 determines the right overturn line L RS is used to calculate the tipping moment at least in the lateral region of the loaded truck crane 10.

[0039] According to this configuration, the overturning line L used to calculate the overturning moment RS , L LS From the ground reaction force of the jacks 38a, 38b, the rated load in the side area based on the stability performance can be calculated with higher accuracy. In addition, since the first rotation angle at which the ground reaction force of the jacks 38a, 38b on the opposite left and right sides is smallest in the turning motion of the side area is known, the control device 12 can sound the alarm 14 or slow down the speed of the turning motion when turning in a direction approaching the first rotation angle.

[0040] Next, the control device 12 detects the right overturn line L RS The intersection point between the left and right symmetrical axes of the loading truck crane 10 and the rear axle center O S It is decided that:

[0041] In this way, the right overturn line L RS and the actual rear axle center O S was determined, but the first left turning angle θ LS and left tipping line L LSThe method of determining the right overturn line L is the same as the method of determining the right overturn line L. RS The effective rear axis center O determined from S The left fall line L LS The effective rear axis center O determined from S In theory it's in the same position.

[0042] The tipping line L calculated from the ground reaction forces of jacks 38a and 38b RS ,L LS Using the actual rear axis center O S By determining the above, the tipping line L can be determined with high accuracy even if the extension width of the outrigger device 33 is changed. RS , L LS can be sought. [Explanation of symbols]

[0043] 10 Loading truck crane 12 Control device 21 Crane equipment 27 Cab 28 Cargo Bed 32 Boom 33 Outrigger device 38a Right jack 38b Left jack L RS Right fall line L LS Left fall line O S Practically centered on the rear axis θ RS Right first turning angle θ LS Left first turning angle

Claims

1. A loading truck crane equipped with a crane device and an outrigger device between the driver's cab and the loading platform, The loading truck crane has: A jack provided at each of the left and right outer ends of the outrigger device; a control device for receiving a ground reaction signal of the jack; The control device includes: When the rotation position of the boom constituting the crane apparatus is in the side area, When rotating the boom in either the left or right side area, The rotation angle when the ground reaction force signal of the other jack of the left or right jack shows the lowest value is defined as the first rotation angle. In a plan view, a straight line passing through the center of a jack located in one of the left and right side regions and having an angle of 90° with the first rotation angle is defined as a tipping line; Calculate the overturning moment using the overturning line. A loaded truck crane characterized by the above.

2. The control device includes: determining a substantial rear axle center from the tipping line; 2. The loading truck crane according to claim 1.

Images