JP5816049B2 - Concrete pump truck - Google Patents

Description

  The present invention relates to a concrete pump vehicle including a concrete pump and a boom device.

2. Description of the Related Art Conventionally, there is a concrete pump truck that is equipped with a boom in which a plurality of beams are connected in a refractable or extendable manner and can place concrete at a high place or a remote place.
By connecting both ends of a hydraulic cylinder (boom drive means) between adjacent beams, the plurality of beams are driven to extend and contract to move the beam on the front (free end) side with respect to the beam on the base (vehicle body) side. It can rotate or expand and contract.
The concrete pump truck delivers the ready-mixed concrete to a desired place by unfolding the tip of the boom folded at the construction site to the placement site and pumping the ready-mixed concrete. Then, the tip of the boom is moved to change the placement location.

JP 2005-536369 A

In the placing work, for example, as shown in FIG. 18, when the second beam 132 is arranged so as to extend substantially vertically upward, the third beam 133 is bent toward the front of the vehicle, and the boom is deployed in a substantially L shape, The third beam 133 tries to rotate counterclockwise by its own weight (in the direction of arrow C1), and applies a load in the direction in which the second refraction cylinder is extended (in the direction of arrow C2).
If the installation work is performed in this position, oil leakage will occur from the seal containing hydraulic oil at the location where the rod passes, and in the worst case, the seal will break and the hydraulic cylinder will not be able to maintain its position. The third beam 133 and the fourth beam 134 supported by the third beam 133 lose support and are dangerous because the tip of the beam descends.

  The present invention has been made in view of the above-described circumstances, and it is possible to suppress a beam drop accident caused by a driving load being applied to a hydraulic cylinder and the hydraulic cylinder being damaged. An object is to provide a concrete pump vehicle having a boom.

In order to achieve the above object, a concrete pump truck according to the present invention includes a boom device in which at least two or more beams are refractably connected, and at least a hydraulic cylinder, and the beam as the hydraulic cylinder extends. In a concrete pump vehicle comprising: a boom drive means for rotating the beam in reverse while the hydraulic cylinder is contracted; and a control means for driving the boom drive means based on an operation signal from the operation means , Further comprising detection means for detecting the attitude of the beam, wherein the control means is based on a detection result of the detection means, and is in a dangerous state when the beam is rotated forward rather than vertically extending. It is characterized by judging.
Thus, the driving operation can be performed safely in order to prevent the hydraulic cylinder from being damaged due to the extraction load being applied to the hydraulic cylinder.

In addition, it has a boom device in which at least two or more beams are refractably connected, and at least a hydraulic cylinder. The beam rotates forward as the hydraulic cylinder extends, while the hydraulic cylinder contracts. In addition, in a concrete pump car comprising a boom drive means for rotating the beam in reverse and a control means for driving the boom drive means based on an operation signal from the operation means, the vehicle further comprises a detection means for detecting the attitude of the beam, The control means determines a dangerous state based on a detection result of the detection means when the attitude of the beam is reversed from the attitude of extending vertically downward.
Thus, the driving operation can be performed safely in order to prevent the hydraulic cylinder from being damaged due to the extraction load being applied to the hydraulic cylinder.

  The control means may notify the dangerous state in the case of a dangerous state. According to this, the operator can grasp that the pulling load is acting on the hydraulic cylinder, and urge the operator to return to the posture where the pulling load is not applied. be able to.

  The control means may stop the boom driving means in a dangerous state, and according to this, it is possible to prevent the hydraulic cylinder from being damaged by the pulling load.

  According to the concrete pump vehicle having such a configuration, the driving operation can be performed safely in order to prevent the hydraulic cylinder from being damaged by driving it with the drawing load applied to the hydraulic cylinder.

It is the side view which showed one Embodiment of the concrete pump truck to which this invention is applied. It is a side view which shows the state which expand | deployed the boom apparatus. FIG. 3 is an enlarged view around a second refraction driving unit in FIG. 2. It is the figure which showed typically the relationship between a boom apparatus and a boom drive means. It is a principal part enlarged plan view of a concrete pump. It is the sectional view on the AA line of FIG. It is a hydraulic circuit diagram of a concrete pump. It is a hydraulic circuit diagram of a boom. It is the figure which showed the operating device. It is a control flowchart figure of a boom drive device. It is the figure which showed the 1st subroutine which performs a correction process with a boom attitude | position. It is the figure which showed the 2nd subroutine which performs the correction process at the time of beam interference. It is the figure which showed the 3rd subroutine which performs the correction process at the time of a drawing posture. It is the figure which showed the 4th subroutine which performs the correction process of slow start. It is the figure which showed the 5th subroutine which performs the correction process of slow stop. It is the figure which showed the 6th subroutine which performs the correction process of turning speed. It is the figure which showed the 7th subroutine which performs the correction process at the time of multiple beam operation | movement. It is a principal part enlarged view of the boom apparatus in a drawing-out attitude | position.

  As shown in FIG. 1, the concrete pump vehicle V includes a boom device B for supplying ready-mixed concrete to a placement position, a concrete pump P for pumping ready-mixed concrete, and the boom device B and the concrete pump P. And a subframe S mounted and fixed to the chassis frame F of the concrete pump vehicle V.

  The chassis frame F is a long member extending in the vehicle front-rear direction, and is arranged in a pair on the left and right sides at a predetermined interval in the vehicle width direction to constitute the vehicle body of the concrete pump vehicle V.

  The subframe S is a long member fixedly disposed along the upper surfaces of the pair of left and right chassis frames F. Like the chassis frame F, the subframe S extends in the vehicle front-rear direction and is parallel to the vehicle width direction at a predetermined interval. A pair is arranged.

The boom apparatus B is demonstrated with reference to FIGS. FIG. 1 is a view showing a state in which the boom device B is in a so-called traveling posture in which the boom device B is folded and disposed along the vehicle body, and FIG. 2 shows the boom device B at the time of driving operation.
The boom device B is disposed at the front portion of the subframe S extending in the vehicle front-rear direction, and is provided on the swivel base 11 fixed to the subframe S, and on the swivel base 11, and is pivotable about a vertical axis. It has the support | pillar 12 and the boom 13 provided in the front-end | tip of this support | pillar 12. The boom 13 is a so-called four-stage boom configured by first to fourth beams 131 to 134 that are connected to each other so as to be bendable.
Further, the detailed structure of the boom 13 will be described. The first beam 131 is rotatably connected to the upper portion of the support column 12. The base of the second beam 132 is pivotally connected to the tip of the first beam 131, the base of the third beam 133 is the tip of the second beam 132, and the base of the fourth beam 134 is the third beam. It is each connected with the front part of 133 so that rotation is possible.

The swivel base 11 and the first to fourth beams 131 to 134 can be pivotally driven by the boom drive means 14 at their respective connecting portions.
The boom drive unit 14 includes a turning drive unit 141, a undulation drive unit 142, and first to third refraction drive units 143 to 145. The swivel driving means 141 is fixed to the swivel base 11 and includes a pair of two relatively disposed swivel cylinders 141L and 141R. The relatively disposed swivel cylinders 141L and 141R are supported by the column 12 via a rack 141a and a pinion 141b. Connected with. The undulation driving means 142 has a undulation cylinder 142 a having a base portion rotatably connected to the support column 12 and a tip portion thereof rotatably connected to the first beam 131. The first refraction driving means 143 includes the first refraction cylinder 143a and the two auxiliary links 143b and 143c as the first beam 131 and the second beam 132, and the second refraction driving means 144 includes the second refraction cylinder 144a and the two refraction cylinders 144a. The auxiliary links 144b and 144c are connected to the second beam 132 and the third beam 133, and the third refraction driving means 145 connects the third refractive cylinder 145a and the two auxiliary links 145b and 145c to the third beam 133 and the fourth beam 134. Are connected to each other in a rotatable manner.

The detailed structure of the second refraction driving means 144 will be described with reference to FIG. FIG. 3 is an enlarged view around the second refraction driving means 144 in FIG. 2, and the second beam 132 and the third beam 133 are shown only at the front part and the base part, respectively.
One end of the second refracting cylinder 144a is an intermediate portion of the second beam 132, and is pivotally connected to a side surface close to the first beam in a traveling posture (FIG. 1) via a pin 144d. Among the two auxiliary links, the boomerang link 144b is connected to one end of the second beam 132 so as to be swingable via a pin 144f, and the other end is one of the two auxiliary links via a pin 144g. The straight link 144c is connected to one end of the straight link 144c. The other end of the straight link 144c is slidably connected to the base of the third beam 133 via a pin 144h. The boomerang link 144b is formed in a greatly curved shape as shown in the figure, and is avoided by going around the outside of the distal end 132a of the second beam 132 (connecting portion with the third beam 133).
With the above configuration, when the second refraction cylinder 144a is contracted from the extended state (the posture of the one-dot chain line), the boomerang link 144b swings clockwise around the pin 144f, and the boomerang link 144b moves via the straight link 144c. Thus, the third beam 133 is transmitted to the third beam 133, and the third beam 133 can be rotated clockwise (in the direction of the arrow B1 in the figure) with respect to the second beam 132.
In addition, each boom drive means 14 including the second refraction drive means 144 may directly connect the hydraulic cylinder to the beam without using an auxiliary link.

FIG. 4 is a diagram schematically showing the relationship between the boom device B and the boom driving means. Here, the boom device B is (1) rotating around the vertical axis of the swivel base 11 (2) rotating the first beam 131 with respect to the column 12 (3) rotating the second beam 132 with respect to the first beam 131. There are five joints: (4) rotation of the third beam 133 with respect to the second beam 132 (5) rotation of the fourth beam 134 with respect to the third beam 133, and one boom drive means 14 is provided for each joint. (Numbers surrounded by double circles in FIG. 4). The undulation driving means 142 and the first to third refraction driving means 143 to 145 are arranged below the joints (2) to (5) in a state in which the boom 13 is extended in a straight line toward the rear of the vehicle. Thereby, if each cylinder is extended, each beam is rotated counterclockwise, and accordingly, the beam tip 135 is raised (in the direction of the arrow BU), and if each cylinder is contracted, each beam is rotated clockwise, The beam tip 135 is moved downward (in the direction of the arrow BD). In addition, the boom 13 has a cantilever shape supported by the support column 12, but if the coordinate system is defined with the joint where each beam undulates as the origin, the beam posture ranges from −90 degrees to +90 degrees. In this case, the weight of each beam acts in the direction of contracting each cylinder.
Then, by operating the boom driving means 14, the first to fourth beams 131 to 134 can be bent alternately, and each joint portion is rotated to move the boom 13 upward. Can stand. Further, the first to fourth beams 131 to 134 can be turned right (in the direction of arrow BR in FIG. 4A) and leftward (in the direction of arrow BL in FIG. 4A).

The column 12 of the boom device B and the first beam 131 to the fourth beam 134 are respectively provided with inclination sensors Se1 to Se5 as detection means Se for grasping the postures of the beams (see FIG. 4). The inclination sensors Se <b> 1 to Se <b> 5 detect the direction of gravitational acceleration and grasp how much the posture of the apparatus is inclined with respect to the vertical line from the direction of gravitational acceleration. The inclination sensor Se1 is fixed to the column 12 and detects the attitude of the concrete pump truck V, and the inclination sensors Se2 to Se5 detect the attitudes of the first beam 131 to the fourth beam 134. The detection values of the inclination sensors Se2 to Se5 are corrected by the detection value of the inclination sensor Se1, so that the relative posture of the boom 13 with respect to the concrete pump car V can be grasped.
In addition, although the detection means Se illustrated the inclination sensor, you may make it grasp | ascertain the attitude | position of each beam 131-134 indirectly from the stroke sensor attached to the cylinder, and may substitute other various sensors.

  The concrete pump vehicle V includes a boom receiver 16 that is fixed to the subframe S and restricts movement of the boom 13 (particularly, the fourth beam 134) in the traveling posture in the vehicle width direction. The boom pipe 15 for guiding the ready-mixed concrete pumped from the concrete pump P to the tip 135 of the boom 13 is fixed along the support column 12 and the boom 13.

  As shown in FIG. 5, the concrete pump P is for pumping fluid such as ready-mixed concrete, and includes a concrete pump main body 2 mounted on the subframe S and a valve provided behind the concrete pump main body 2. The apparatus 3 is provided.

  As shown in FIG. 5, the concrete pump body 2 is a hydraulically driven reciprocating piston pump, and includes a left pump cylinder 21 and a right pump cylinder 22 that are parallel to each other. A left drive cylinder 23 for driving the left pump cylinder 21 and a drive cylinder 24 for driving the right pump cylinder 22 are integrally connected to the base ends of the pump cylinders 21 and 22 via a center frame 26. . Pump pistons 21a and 22a are slidably fitted in the pair of pump cylinders 21 and 22, respectively, and drive pistons 23a and 24a are slidably fitted in the pair of drive cylinders 23 and 24, respectively. Is provided. A pump piston 21 a in the left pump cylinder 21, a drive piston 23 a in the left drive cylinder 23, a pump piston 22 a in the right pump cylinder 22, and a drive piston 24 a in the right drive cylinder 24 form the center frame 26. The piston rods 25 are slidably penetratingly connected to each other. The drive pistons 23a and 24a partition the corresponding drive cylinders 23 and 24 into piston oil-side tip oil chambers 23b and 24b and piston-side base oil chambers 23c and 24c. The front ends of the pump cylinders 21 and 22 are opened as discharge ends 21b and 22b. The discharge ends 21b and 22b of the pump cylinders 21 and 22 are connected to and communicated with the front surface of the valve device 3.

  As shown in FIG. 5, the valve device 3 includes a valve casing 31, a bottom cover 32, an S-shaped valve 33 (that is, an oscillating valve pipe), an S-shaped valve driving means 34, and a discharge pipe 35. . The valve casing 31 is formed in a frame shape by a front wall 31a, a rear wall 31b, and both side walls 31c, and a lower part is opened by an opening 31d. The bottom lid 32 opens and closes an opening 31d at the bottom of the valve casing 31 with a cylinder or the like (not shown).

  A curved tubular S-shaped valve 33 is housed and supported at the lower part of the valve casing 31. This S-shaped valve 33 is rotatable around the axis of a rotation support shaft 33a that is integral with the S-shaped valve 33 and parallel to the axis of each pump cylinder 21, 22, and the tip of the pair of pump cylinders 21, 22 (In other words, the discharge ends 21b and 22b) and the suction port 33b can be switched and communicated alternately.

  As shown in FIGS. 5 and 6, an S-shaped valve for switching and driving the S-shaped valve 33 by rotating the rotating support shaft 33a in synchronization with the operation of both pump pistons 21a and 22a. Drive means 34 is connected. In the S-shaped valve driving means 34, the tip portions of the left single-acting valve driving cylinder 34a and the right single-acting valve driving cylinder 34b, which are configured in cooperation with each other, extend integrally from the rotating support shaft 33a. The bases of both valve drive cylinders 34a and 34b are connected to the concrete pump main body 2 so as to be rotatable.

  During the operation of the concrete pump P, the pair of valve drive cylinders 34a and 34b is configured such that one of the pair of pump cylinders 21 and 22 that is in a state of sucking ready-mixed concrete is put into the valve casing 31, and the ready-mixed concrete is pumped. The S-shaped valve 33 is switched and controlled so that a certain one is alternately connected to the suction port 33b to smoothly feed the ready-mixed concrete. That is, the S-shaped valve 33 has a first switching position where the suction port 33b is connected to the discharge end 21b of the left pump cylinder 21, and a second switching position where the suction port 33b is connected to the discharge end 22b of the right pump cylinder 22. Can be reciprocated (oscillated) between the first and second switching positions by the extension operation of the left valve driving cylinder 34a, and the second switching position by the extension operation of the right valve driving cylinder 34b. Each is switched and held.

  As shown in FIG. 5, the discharge pipe 35 has a front end connected to the rear wall 31 b of the valve casing 31 and is always in communication with the S-shaped valve 33, and a rear end thereof is a boom pipe of the boom device B. 15 (see FIG. 1).

  As shown in FIG. 1, the hopper H is connected to the upper part of the valve casing 31, and receives ready-mixed concrete.

A hydraulic circuit for driving the concrete pump 2 and the boom device B will be described with reference to FIGS. 7 and 8. The concrete pump vehicle V includes a variable displacement first hydraulic pump PU1 and a second hydraulic pump PU2 driven by the engine En. Both hydraulic pumps PU1 and PU2 are variable displacement hydraulic pumps (axial piston pumps in this embodiment), and the discharge capacity can be changed by operating the swash plate. The first hydraulic pump PU1 is connected to the concrete pump body 2 via a switching valve V1 for switching the operating direction of the left and right drive cylinders 23, 24 and a switching valve V2 for switching the operating pressure of the left and right drive cylinders 23, 24. Yes. The first hydraulic pump PU1 is connected to the S-shaped valve driving means 34 via a valve switching drive means V3 that switches and drives the S-shaped valve.
On the other hand, the second hydraulic pump PU2 is connected to the boom driving means 14 via a boom switching valve V4.
The pump body 41 of the first hydraulic pump PU1 and the pump body 42 of the second hydraulic pump PU2 are connected in series by a drive shaft 43 and are driven by the engine En of the concrete pump car V.

FIG. 8 is a detailed hydraulic circuit diagram of the boom switching valve V4 and the boom driving means 14.
The boom switching valve V4 is provided with six switching valves v40 to v45, and the boom driving means 14 is connected as shown in the figure via counter balance valves v51 to v54. The hydraulic oil sent from the second hydraulic pump PU2 is first connected to the boom drive means 14 via the solenoid valves v40 and v41 to v45. Note that v41 to v45 are so-called proportional control valves that change their opening according to an operation input to the solenoid (hereinafter simply referred to as proportional valves v41 to v45).
Then, by changing the output signal to the solenoid and increasing the opening of the proportional valves v41 to v45, the amount of hydraulic oil supplied to the boom drive means 14 can be increased (the operation speed is increased), and the proportional valve By reducing the opening degree of v41 to v45, the amount of hydraulic oil supplied to the boom drive means 14 can be reduced (the operation speed is reduced). Further, since the proportional valves v41 to v45 are provided according to the number of the boom driving means 14, the proportional valves v41 to v45 can individually adjust the respective speeds of the boom driving means 14. For example, even when the undulation cylinder 142a and the first refraction cylinder 143a are operated simultaneously and at different speeds, the opening degrees of the corresponding proportional valves v42 and v43 may be changed, respectively. Does not affect. Therefore, even if the amount of hydraulic oil supplied to increase the speed of one is changed, the speed of the other can be maintained, and the boom 13 does not perform an operation that is not assumed by the operator.

  In addition, only one of the boom device B and the jack J is operated by the electromagnetic valve v40, and the jack J is erroneously operated while the boom device B is being driven, and the concrete pump car V becomes in an unstable posture. Is prevented. The cylinders 142a to 145a are connected via pilot-type counter balance valves v51 to v54 so that the cylinders 142a to 145a maintain their postures unless supplied with hydraulic oil.

  The concrete pump vehicle V includes a control device C (FIG. 1). The control device C receives an input from the operation device R and a rotation speed sensor S as a rotation speed grasping means for measuring the rotation speed of the engine En. An instruction signal is output to the electromagnetic switching valve in order to perform an appropriate operation based on the input of the operator and the operating state of the engine. The control device C uses a programmable logic controller (PLC for short).

FIG. 9 is a view showing the operating device R. The operating device R includes a main power switch 51 for starting the boom device B and the concrete pump P of the concrete pump vehicle V, a pump start switch 52 for starting the raw concrete pumping work of the concrete pump P, and the rotation of the engine. Rotation speed switches 53a and 53b for increasing and decreasing the number, discharge control switches 54a and 54b for increasing and decreasing the discharge amount of the concrete pump P, a right turning switch 55a and a left turning switch 55b for turning the boom device B left and right, Beam raising and lowering switches 56a to 56h for raising and lowering the beam and boom speed control switches 57a and 57b for adjusting the operating speed of the boom device B are provided. When the operator wishes to turn the first beam 131 upright, when the operator depresses the first beam standing switch 56a, the control device R transmits a first beam standing instruction to the control device C, and the control device C responds to the instruction. Based on this, the hoisting cylinder 142 is extended to rotate the first beam 131 upright (counterclockwise rotation in FIG. 1). When the operation speed of the boom device B is to be changed, an instruction to switch to operate at a speed higher than the current speed when the “speed” switch 57a of the boom speed control switch is pressed, and the “slow” switch 57b is set. When pressed, an instruction to switch to operate at a speed slower than the current speed is output to the control device C. The control device C increases or decreases the boom operating speed based on the speed instruction.
Instead of the “speed” and “slow” switches 57a and 57b, the operation speed may be indicated by a so-called inching operation in which the boom operation switch is pressed a plurality of times, a joystick type, or the like.

The operation of the concrete pump vehicle V configured as described above will be described.
First, by operating the boom device B, the boom tip 135 is deployed to the placement position. When the ready-mixed concrete is pumped, first, the S-shaped valve 33 and the pump pistons 21 and 22 are operated. That is, the right valve drive cylinder 34b is extended to swing the S-shaped valve 33 to the right in the valve casing 31, the suction port 33b of the S-shaped valve 33 is connected to the discharge end 22b of the right pump cylinder 21, The discharge pipe 35 and the right pump cylinder 22 are connected.
In this state, the pump piston 21a of the left pump cylinder 21 is retracted and the pump piston 22a of the right pump cylinder 22 is advanced to suck the concrete in the valve casing 31 into the left pump cylinder 21.

Next, the left valve drive cylinder 34a is extended to swing the S-shaped valve 33 to the left, and the S-shaped valve 33 communicates with the left pump cylinder 21.
In this state, the pair of pump pistons 21 and 22 are operated in reverse to the above. That is, the pump piston 22a of the right pump cylinder 22 is retracted and the pump piston 21a of the left pump cylinder 21 is advanced. As a result, the right pump cylinder 22 sucks the ready-mixed concrete in the valve casing 31, and the left pump cylinder 23 pushes the ready-mixed concrete sucked into the S-shaped valve 33 and discharge piping. 35 is pumped.
By repeating the above operation, the ready-mixed concrete in the valve casing 31 can be continuously pumped to the discharge pipe 35.

Next, control for adjusting the operation of the boom device B will be described.
FIG. 10 is a flowchart relating to the adjustment of the operation speed of the boom device B in the processing in the control device C, and FIGS. 11 to 17 are subroutines for partial processing in FIG.

First, an overall processing flow for adjusting the operation speed will be described with reference to FIG. This control is started when one of the switches of the operating device R which instructs the operation of the boom device B (one of the turning switches 55a and 55b and each of the beam hoisting switches 56a to 56h or a combination thereof) is pressed. At this time, which switch is pressed is temporarily stored, and the time T from the start of pressing is started by the timer. The control device C reads the detection value from the detection means Se (step S1).
In step S2, the control device C calculates the optimum operating speed VA of the boom drive means 14 from the current posture of the boom 13 (first subroutine). Next, in step S3, the optimum operating speed VB is calculated from the current posture of the boom 13 based on the fear of contact between the beams or between the beam and the beam driving means 14 or whether it is necessary to avoid contact ( Second subroutine).

Subsequently, it is determined from the current posture of the boom 13 whether or not the boom driving means is in an overloaded posture, and an optimum operating speed VC is calculated when overloaded (step S4, third subroutine).
In step S5, the operation speed VD based on the elapsed time from the start of pressing the switch is calculated (fourth subroutine). In step S6, the optimum operation speed VE is calculated from the relative angle between the beams 131 to 134. (Fifth subroutine). In order to easily align the boom 13 and the boom receiver 16, a turning speed VF is calculated according to whether or not it is in the retracted posture (step S7, sixth subroutine).

As described above, the operation speeds VA to VF for which individual optimum values are calculated according to various situations are selected and determined as the operation speed from among the operation speeds VA to VF (hereinafter, the selected operation speed is selected). Also called velocity Vs). When the speed designated by the worker is slower than the calculated speed, the operation speed designated by the worker is set as the selection speed Vs.
The operation speeds VA to VF and the selection speed Vs calculated in steps S2 to S8 are the boom drive means 14, that is, the expansion / contraction speed of each hydraulic cylinder. In step S9, the amount of hydraulic fluid required for each hydraulic cylinder (hereinafter referred to as the required flow rate Qs) is calculated from the selected cylinder specifications from the selected speed Vs of each hydraulic cylinder.

  In step S10, the required flow rate Qs is corrected depending on whether or not all the operations can be sufficiently performed when a plurality of joints are operated simultaneously. Then, the opening degree of the proportional valves v41 to v45 is determined based on the final required flow rate Qs. And the control apparatus C emits the output signal which switches the solenoid valve v40 to the operation side of the boom apparatus B, and the output signal with respect to each solenoid SOL11-SOL52 of a proportional valve (step S11).

When the operator's switch operation, that is, the operation of the boom device B continues (NO in step S12), the process returns to step S1 and the processing is continued. When the operation by the operator is finished (YES in step S12), the boom device B is stopped and the operation is ended (end).
The above is the overall processing flow for adjusting the operation speed.

From here, detailed processing (subroutine processing) of some steps will be described with reference to FIGS.
First, the processing of the first subroutine will be described with reference to FIG. In the first subroutine, the operation speed VA is calculated so that the speed of the beam tip located at the most distal end is within the set speed from the posture of each beam.
When the process moves into the first subroutine, first, the tip position of each beam is calculated as a coordinate value (step S101). This calculation can be calculated from the attitude (tilt angle) of each beam and the known beam length.
Then, based on the obtained coordinate value [xi, yi], the position corresponding to the most advanced as the boom 13 is obtained. Here, the case where the undulation driving means 142 is operated in a posture surrounded by a one-dot chain line will be described in detail. Using the base of the first beam 131 as a reference, the distance r11 to the tip of the first beam 131 (the same as the known length of the first beam 131), the distance r12 to the tip of the second beam 132, and the third beam 133 A distance r13 to the tip of the first beam and a distance r14 to the fourth beam tip are calculated. Then, the maximum distance (r13 in the illustrated posture) is obtained from r11 to r14.
The maximum distance based on the bases of the second to fourth beams is also calculated separately.

In this embodiment, since the respective ends of the beams are connected to each other, the position corresponding to the leading edge is regarded as the same position as the joint of each beam. However, if it is a special beam structure and has a protruding part at a position different from the joint between the beams, the coordinate value of the protruding part is calculated separately in addition to the coordinate value of the joint, What is necessary is just to calculate.
From the maximum distance obtained in step S102, the maximum speed VA2 of the undulation driving means 142 that can move the tip position as fast as possible is calculated, and the maximum speed VAi of the other beam driving means is also calculated from the respective maximum distances rij. Then, a value is sent to the main routine as the maximum speed VAi. For example, when the speed at which the most advanced position can be moved as fast as possible is 1 meter per second stipulated by JIS, the stroke of the undulating drive means 142 (the undulating cylinder 142a) such that the most advanced position is 1 meter per second. If converted into a speed, the maximum speed VA1 is obtained.

Thus, in the first subroutine, since the maximum speed VA is changed by the maximum distance r (step S103), when the boom 13 is expanded widely, for example, in a straight line, the operating speed of the driving means is reduced. When the boom 13 is folded, the operating speed of the driving means can be increased. The upper limit of the speed at which the boom 13 can operate can be changed according to the posture of the boom 13.
In step S102, the leading edge of the boom 13 is obtained from the postures of the beams 131 to 134, and the operation speed is determined based on the leading edge in step S103. The cutting-edge upper limit speed that is the location can be made substantially the same.
Although the maximum speed VAi is obtained for each boom drive means, if there is no need to obtain the operation speed VA for all the beam drive means, the value may be obtained only for the necessary operation.

Next, processing in the second subroutine will be described with reference to FIG.
Depending on the posture of the boom 13, the beam driving means 14 and the beam may come into contact with each other. Therefore, since the posture of the boom 13 and the posture of the beam driving unit 14 correspond one-to-one, the operation speed VB is calculated based on whether there is a possibility of contact based on the posture of the boom 13. Specifically, in the boom apparatus B of the embodiment, the second beam 132 as the reference beam has the third beam 133 (one beam) at one end and the first beam 131 (the other beam) at the other end. Are rotatably connected. When the second refracting cylinder 144a is contracted, the third beam is developed (rotated toward a position that is in a straight line with the second beam 132) via the auxiliary links (boomerang link 144b, straight link 144c).
Among the second refraction driving means 144, in particular, the second refraction cylinder 144a and the boomerang link 144b approach the first beam 131 as the third beam 133 is developed (see FIG. 3). If the second beam 132 is close to the first beam 131 in this state, the second refraction cylinder 144a or the boomerang link 144 and the first beam 131 come into contact with each other and may be damaged in the worst case. Therefore, the second subroutine calculates an operation speed VB that can suppress contact.

Specifically, when the process proceeds to the second subroutine, first, the relative angle θ12 between the first beam 131 and the second beam 132 and the relative angle between the second beam 132 and the third beam 133 are set. θ23 is calculated (step S201).
From here, the processing changes depending on which operation instruction from the operator is an instruction to rotate which beam in which direction. First, it is determined whether or not the third beam 133 has been instructed to be deployed (turning clockwise in FIGS. 2 and 3) (step S202). If it is a deployment instruction for the third beam 133 (YES in step S202), the process proceeds to step S203. When the third beam 133 is deployed, the second driving unit 144 approaches the first beam 131, and therefore it is determined whether or not the relative angle θ12 is equal to or smaller than the second predetermined storage angle θa. When θ12 is equal to or smaller than θa, it is determined that the vehicle is in the proximity state (YES in step S203), a warning is issued in step S204, and a value is returned to the main routine so that the operation speed VB is zero, that is, stopped in step S205.
Note that the warning in step S204 can be arbitrarily selected from a lamp that lights up and appeals visually, an auditory appeal such as a buzzer, and a warning that informs the worker that the condition is present. .

If it is not a deployment instruction for the third beam 133 (NO in step S202), it is determined in step S206 whether the second beam 132 is a storage instruction. When the second beam 132 is retracted and rotated (YES in step S206), the protrusion amount of the second refraction driving means 144 is large (YES in step S207), and the relative angle θ12 of the first second beam is the first predetermined value. If the angle is equal to or smaller than the storage angle θc, it is determined as a close state (YES in step S208), and an output value is returned to stop the warning and beam operation in steps S204 and S205.
If the relative angle θ12 is greater than or equal to the second predetermined storage angle θa in step S203, the second beam 132 is sufficiently deployed, and the second driving means 144 and the second driving means 144 are driven to drive the third beam 133. One beam has no fear of contact, and jumps to step S209 via “A”.
If the operation is other than the storing operation of the second beam 132 in step S206 (NO in step S206, if the third beam 133 is deployed in the upstream step S202, the process proceeds to step S203, so the third beam deployment is performed). The operation is also excluded), and since there is no relation to the contact between the second refraction driving means 144 and the first beam, the process jumps to step S209.
Further, there is no fear of contact even when the protrusion amount of the second refraction driving means 144 is small (NO in step S207) or when the first beam 131 and the second beam 132 are separated (NO in step S208). Jump to step S209.
In step S209, the same speed value as that of the normal operation (in this embodiment, VA) is returned to the main routine as the value of the operation speed VB.

The relative angle θ12 between the second beam 132 and the third beam 133 is smaller than the second predetermined storage angle θa, and the second beam 132 (reference beam) and the third beam 133 (one beam) are close to each other. Sometimes (NO in step S203, NO in step S208), it is determined that folding is possible, and the operating speed VB is defined. Accordingly, since the plurality of beams are driven only when the second refraction driving means 144 is not close to the first beam 131 (the other beam), the second refraction cylinder 144a and the auxiliary link 144b, Boom refraction accidents due to the contact and breakage of 144c and the first beam 131 can be suppressed, and the placing operation can be performed safely.
Then, when the third beam 133 (one beam) is unfolded by rotating counterclockwise in FIG. 2 (YES in step S202), the approach is performed when the relative angle θ12 is smaller than the predetermined storage angle θa. Since the state is determined (YES in step S203), it is possible to prevent the first beam 131 from being broken in preparation for placing. When the second beam 132 (reference beam) is stored by rotating counterclockwise in FIG. 2 (YES in step S206), the relative angle θ23 is equal to or greater than the predetermined storage angle θb, and the relative angle θ12 is Since the proximity state is determined when the angle is equal to or smaller than the predetermined storage angle θa, it is possible to prevent the first beam 131 from being broken in preparation for traveling. The determination in step S208 is the second predetermined storage angle θa, but may be a different value.
Further, the operator is alerted by notifying the proximity state in step S204, and the speed of the boom drive means 14 is set to zero in step S205 to stop the beam operation. A refraction accident can be prevented.

In addition, since the protrusion amount of the second refraction driving means 144 is linked to the relative angle θ23 between the second and third beams, the determination is made using the relative angle θ23 in step S207.
In the present embodiment, since the second refraction driving means 144 may be in contact with the first beam 131, the processing is performed in the second subroutine as described above. If there is a possibility of contact with .about.134, processing may be performed together.

The third subroutine will be described with reference to FIG. In the third subroutine, it is determined whether or not each of the hydraulic cylinders is in a posture in which the own weight of the boom 13 acts in the extending direction in the present embodiment, and if it is the posture, a warning is given and the operation is prohibited.
First, when the process proceeds to the third subroutine, it is determined in step S301 whether or not the drawing posture is set. Here, the drawing posture can be determined based on the posture of the third beam 133 on the free end side when the second refraction cylinder 144a is described. This will be described in detail with reference to a schematic diagram surrounded by a one-dot chain line. The direction in which the third beam rotates as the second refraction cylinder 144a extends is defined as “forward rotation”, and the reverse rotation is defined as “reverse rotation”. When the attitude of the third beam 133 is rotated positively from the attitude in which the third beam 133 extends vertically upward with respect to the tip of the second beam 132 as shown in (a), that is, the attitude of the third beam 133 is larger than +90 degrees. Alternatively, as shown in (b), the posture in which the third beam 133 is rotated backward relative to the tip of the second beam 132, that is, the posture of the third beam 133 is smaller than −90 degrees. In this case, the weight of the third beam acts in the direction of extending the second refraction cylinder 144a. This posture is defined as a pulling posture, and if it is such a pulling posture (YES in step S301), a warning is issued in step S302, and the operation speed VC is set to zero, that is, stopped in step S303. Returns the value.

As a result, the second refraction cylinder 144a in which the pulling posture continues and the second refraction cylinder 144a continues to be forcibly extended, for example, so that the seal fitted at the location where the rod passes is damaged by the high pressure hydraulic oil. Damage to 144a can be suppressed.
On the other hand, when the posture is not the drawing posture in step S301 (NO in step S301), the same speed value as that of the normal operation (in this embodiment, VA) is returned to the main routine as the value of the operation speed VC.
In addition, the operator is alerted by notifying the proximity state in step S302, and the speed of the boom drive means 14 is set to zero in step S303 to stop the beam operation. Breakage can be prevented.
For example, when it exceeds −80 degrees or +80 degrees and approaches the pulling posture, an operator may be warned separately, or a slow operation speed value may be returned to the main routine.

In the fourth subroutine, an operation speed for so-called slow start is defined in order to prevent the beams 131 to 134 from shaking due to an abrupt operation.
In the fourth subroutine, the operation speed is defined by the time measured by the timer. First, if the first set time ta has elapsed in step S401 (YES in step S401), the operation speed VD is set to a preset low speed value (step S402). If the time measured by the timer is between the first set time ta and the second set time tb (NO in step S401 and YES in step S403), the operation speed is gradually increased with the time measured by the timer. The operating speed VD is defined so as to be the speed.
When the second set time tb has elapsed (NO in step S403), the operating speed VD is set to a preset high speed value (step S405).
According to this, since the speed of the beams 131 to 134 is low at the start of operation, the boom driving means 14 can be vigorously expanded and contracted to prevent the beams 131 to 134 from shaking due to high speed operation from a stationary state. Can do.
The acceleration in step S404 may be linearly changed (a straight line according to the number of elapsed seconds, a curve that smoothly accelerates from a low speed and smoothly transitions to a high speed, etc.), and accelerates in steps. You may prescribe | regulate to do. Steps S401 and S402 may be omitted, and acceleration may be performed from the start of pressing (zero speed).

In the fifth subroutine shown in FIG. 15, the optimum operation speed VE is calculated from the relative angle between the beams 131 to 134. This is because, for example, the beam 13 is folded to the running posture, so that noise caused by vigorous contact when the beams 131 to 134 are brought into contact with each other and damage to the beams 131 to 134 are suppressed.
When the process proceeds to the fifth subroutine, first, the relative angle θij between the beam to be operated and the beam that supports the beam is obtained (step S501). If the obtained relative angle θij is larger than the first predetermined relative angle θd (YES in step S502), the operation speed VE is set to a preset high speed value because the relative posture still has a margin until contact. (Step S503). When the relative angle θij is smaller than the first predetermined relative angle θd and larger than the second predetermined relative angle θe (NO in step S502 and YES in step S504), the operating speed VE is decreased as the relative angle θij decreases. The operation speed VE is defined so as to be a slow speed (step S505).

If the relative angle θij is smaller than the second predetermined relative angle θe (NO in step S504), the operating speed VE is set to a preset low speed value, and a loud sound or momentum is generated when the contact is made. It is possible to prevent the beams 131 to 134 from being damaged due to good contact.
Further, since the operation speed VE is gradually reduced between the first relative angle θd and the second relative angle θe as the relative angle θij becomes smaller, each beam 131 caused by suddenly decelerating or stopping. ~ 134 can be prevented from shaking.

Note that the deceleration in step S505 may be linearly changed (a straight line corresponding to the relative angle, a curve that smoothly shifts from high speed to low speed, and smoothly shifts to low speed, etc.), and decelerates stepwise. It may be defined as follows. The second relative angle θe may be set to zero degrees, steps S504 and S505 may be changed and step S506 may be omitted, and the operation speed VE may be defined to be zero when the relative angle θij is zero.
Before moving from step S501 to S502, it is determined whether or not the operation direction is the folding direction, and only when the instruction is the folding direction, the processing from step S502 may be processed. The operation in the non-deploying direction can always operate the beams 131 to 134 at a high speed without being affected by the speed correction by the fifth subroutine.
If it is determined that the relative angle θij is zero, that is, the two beams are in contact with each other before jumping to step S506, the main routine is set so that the operation speed VE is set to zero, that is, the beam operation is stopped. A value may be returned.

The detailed processing of the sixth subroutine will be described with reference to FIG.
The sixth subroutine proceeds only when a turning instruction is given from the operator. Then, in order to easily align the boom 13 and the boom receiver 16, a turning speed VF is calculated according to whether or not it is in the retracted posture.

  First, in the sixth subroutine, it is determined whether or not the undulation angle θ1 of the base beam closest to the vehicle body (the first beam 131 in this embodiment) is equal to or smaller than a predetermined undulation angle θf (step S601). Here, when it is close to a standing posture, that is, when the undulation angle θ1 is larger than the predetermined undulation angle θf (YES in step S601), the turning speed is changed to step S602 because the turning is performed during the placing operation. Is a preset high speed value. On the other hand, when the undulation angle θ1 is smaller than the predetermined undulation angle θf (NO in step S601), the first beam 131 and the first beam 131 are used to determine whether or not the boom has been projected substantially horizontally. It is determined whether or not the relative angle θ12 between the two beams 132 is equal to or smaller than a predetermined folding angle θg (step S603). When the relative angle θ12 is larger than the folding angle θg, since it is horizontal placement (NO in step S603), the process jumps to step S602 to set the turning speed to a high value. On the other hand, when the relative angle θ12 is smaller than the folding angle θg (YES in step S603), the vehicle is turning to store the boom 13. In step S604, it is determined whether or not the turning angle is within a predetermined turning range. The turning angle is detected by turning angle detection means Sr (rotary encoder, see FIG. 4) fixed to the turntable. If the turning angle is within a predetermined turning range approaching the boom receiver 16 in step S604 (YES), a warning is given that the boom receiver 16 has approached and decelerated (step S605), and the turning speed is set to a low speed set in advance. Value.

According to this, since the turning is performed at a low speed based on the undulation angle of the first beam 131 (the base beam closest to the vehicle body) in step S601, the turning speed is too high when the boom 13 is turned when the boom is retracted. Thus, it is possible to prevent a waste of work such as excessive travel of the boom receiver 16 and reverse rotation again.
When the relative angle θ12 is large, the driving is being performed when the speed is low, so the speed is kept high (NO in step S603 to step S602), and the turning angle is limited to a predetermined turning range. Since the low speed is defined (YES in step S604), it is possible to prevent the turning speed from being slow when the alignment is not performed.
Note that step S603 and step S604 may be omitted, and the vehicle may be rotated at a low speed depending only on the undulation angle θ1 of the first beam 131.
Further, although the rotary encoder is exemplified as the turning angle detecting means Sr, other sensors or the like may be used. In this case, it is only necessary that the beam 13 and the boom receiver 16 can be grasped.

Finally, with reference to FIG. 17, the detailed processing of the seventh subroutine will be described.
In a boom having a plurality of joints as in the boom device B of the present embodiment, the amount of hydraulic oil supplied from the second hydraulic pump PU2 may be exceeded when simultaneously operating the plurality of joints. In this case, some of the joints with a small load rotate normally, while the other joints become sluggish due to insufficient hydraulic oil. Then, for example, when placing on the second floor A of the construction site as shown in FIG. 2, the fourth beam 134 rotates in the standing direction (counterclockwise in FIG. 2) and the third beam 133. Must be rotated in the lying down direction (clockwise in FIG. 2). At this time, when the lowering rotation of the third beam has priority over the upright rotation of the fourth beam 134, the boom tip 135 comes into contact with the second floor A. Therefore, it is the role of the seventh subroutine to add speed correction during simultaneous operation. Accordingly, when only an operation instruction for one joint is given, the process may not be shifted to the seventh subroutine.

When operation instructions are given to a plurality of joints, the process proceeds to the seventh subroutine, and all necessary flow rates Qi corresponding to the operation instructions are picked up (step S701). The required flow rate Qi is a flow rate per unit time obtained based on the operating speed of the hydraulic cylinder in step S9 of the main routine.
Then, all the necessary flow rates that have been picked up are summed, and the amount of hydraulic oil (total hydraulic oil amount Qs) required for operation from now on is calculated (step S702). On the other hand, in step S703, the discharge flow rate Qp of the second hydraulic pump PU2 that supplies hydraulic oil for driving the boom device B is calculated based on the engine speed from the speed sensor S. As the discharge flow rate Qp, the discharge flow rate per unit time can be calculated from the engine speed and displacement. In the present embodiment, the rotation speed sensor S and step S703 constitute the discharge flow rate grasping means. The discharge flow rate grasping means may be other means (for example, a flow meter is provided in the hydraulic circuit and an output signal of the flow meter is received).

Next, in step S704, it is determined whether or not the total hydraulic oil amount Qs exceeds the discharge flow rate Qp. When the demand exceeds the supply (YES in step S704), the flow rate (operating flow rate Qm, operating speed of the boom 13) when actually operating in step S705 is uniformly reduced. Specifically, the speed is uniformly reduced by adding the ratio of the discharge flow rate Qp to the total required flow rate Qs to the required flow rate Qi. In addition, although this deceleration may be decelerated by a preset ratio, the same ratio may be integrated so that the ratios of the respective operation speeds do not vary.
On the other hand, if the demand is less than the supply (NO in step S704), the operating flow rate Qmi is corrected to the required flow rate Qi because the supplied hydraulic oil does not run short even if the required flow rate is operated. No (step S706).

  As described above, the control unit C determines the necessary flow rate Qs of the beam driving unit 14 based on the operation signal from the operation unit R, and when the discharge flow rate Qp grasped by the discharge flow amount grasping unit is exceeded (YES in step S704), Since the operation speed of the beam driving means 14 is limited, it is possible to suppress a contact accident with a building due to the movement of the boom 13 which is easy to move. In step S705, the operating flow rate Qmi, that is, the operating speed of each boom, is limited while maintaining the speed ratio instructed by the operating means, so that the speed is driven slowly at the ratio instructed by the operator. Thereby, it can prevent that the boom 13 becomes a motion which an operator does not assume, and a boom can be driven safely.

  In addition, this invention is not limited to the said Example, A various Example is possible within the scope of the present invention. For example, in the above-described embodiment, the boom device B has been described as an example of a four-stage boom having four beams. However, the boom device B can be applied to other numbers of boom devices B. The boom device B of the above embodiment is a refraction type that supports each of the beams 131 to 134 so as to be rotatable. However, the boom device B is a telescopic boom in which the beam on the front side slides relative to the beam on the base side. May be.

In order to grasp the rotational speed of the engine En, the rotational speed sensor S is attached to the engine En. However, the output signal for controlling the rotational speed of the engine En from the control device C and the increase / decrease in the rotational speed of the engine from the operating device R. Instructions may be substituted.
Although the axial piston pump is taken as an example as the first and second hydraulic pumps PU1 and PU2, other types of variable displacement hydraulic pumps or constant displacement hydraulic pumps may be used.

  Further, the predetermined storage angles θa and θc, the set times ta and tb, and the predetermined relative angles θd and θe may all be set to the same value, or may be set to different values for each beam.

In the above embodiment, the control device C is a PLC, but various control devices such as a relay circuit and an electronic circuit can be substituted.
9 illustrates a transmitter that wirelessly transmits an operation signal to the concrete pump vehicle V, but the concrete pump vehicle V may be provided with an operation switch having the same function (not illustrated). .
In the above embodiment, the piston type concrete pump is taken as an example. However, the present invention may be applied to a concrete pump vehicle equipped with a concrete pump of another mechanism such as a squeezed type concrete pump.

V Concrete pump truck P Concrete pump B Boom device 13 Boom 131 First beam (the other beam)
132 Second beam (reference beam)
133 Third beam (one beam)
134 4th beam 14 Boom drive means 144 2nd refraction drive means 144a 2nd refraction cylinder 144b Auxiliary link 144c Auxiliary link PU1 1st hydraulic pump PU2 2nd hydraulic pump S Rotational speed sensor (discharge flow rate grasping means)
Se detecting means Sr turning angle detecting means C controller v41 switching valve (for turning drive means)
v42 selector valve (for undulation drive means)
v43 selector valve (for first refraction drive means)
v44 selector valve (for second refraction drive means)
v45 selector valve (for third refraction driving means)
R Operating means

Claims (4)

A boom device that refractably connects at least two or more beams;
A boom driving means having at least a hydraulic cylinder and rotating the beam forward as the hydraulic cylinder extends, and reversely rotating the beam as the hydraulic cylinder contracts;
In a concrete pump car comprising a control means for driving the boom drive means based on an operation signal from the operation means,
It further comprises detection means for detecting the attitude of the beam,
The concrete pump car characterized in that the control means determines a dangerous state based on the detection result of the detection means when the attitude of the beam is forwardly rotated rather than the attitude extending vertically upward . A boom device that refractably connects at least two or more beams;
A boom driving means having at least a hydraulic cylinder and rotating the beam forward as the hydraulic cylinder extends, and reversely rotating the beam as the hydraulic cylinder contracts;
In a concrete pump car comprising a control means for driving the boom drive means based on an operation signal from the operation means,
It further comprises detection means for detecting the attitude of the beam,
The concrete pump car characterized in that the control means determines a dangerous state based on the detection result of the detection means when the attitude of the beam is reversed from the attitude of extending vertically downward.   The concrete pump vehicle according to claim 1 or 2, wherein the control means notifies a dangerous state in a dangerous state.   The concrete pump vehicle according to claim 1, wherein the control means stops the boom drive means in a dangerous state.

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