JP2002322980A - Fluid material conveying device and concrete pump vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concrete conveying device which enables the application of concrete at high places without any problem and which is durable and cost-effective, and a concrete pump vehicle on which the concrete conveying device is to be mounted. SOLUTION: The concrete conveying device comprises concrete cylinders 1, 2, a communication switching tube 6 supported in such a manner that it can be selectively connected with either of the concrete cylinders 1, 2, a hydraulic cylinder 7 for activating the communication switching tube 6 such that it is selectively connected with either of the concrete cylinders 1, 2, hydraulic cylinders 11, 12 for activating the concrete cylinders 1, 2 such that they intake or discharge concrete, a hydraulic pump 16 for activating each of the hydraulic cylinders, and a variable volume mechanism 20 for varying the discharge rate of the hydraulic pump 16. In such a concrete conveying device, when hydraulic pressure is introduced to the hydraulic cylinder 7, the discharge rate of the hydraulic pump 16 is increased so as to speed up the activating speed of the hydraulic cylinder 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transport device for transporting a fluid such as concrete, earth and sand, and a concrete pump truck.

[0002]

2. Description of the Related Art For construction of a concrete structure such as a reinforced concrete structure, a concrete pump truck having a long boom and capable of placing concrete at a high place is used. FIG. 3 shows an example of the structure of a concrete transport device mounted on a concrete pump truck. The concrete conveying device in FIG. 3 has a structure in which the concrete is sucked / discharged alternately by the two concrete cylinders 1 and 2 and the concrete is continuously discharged from the end of a boom (not shown). The detailed configuration of each part of the concrete transport device will be described later, and the operation of the illustrated concrete transport device will be described below.

When a signal instructing the start of operation is input to the control unit 25, a switching signal is output to the electromagnetic switching valve 17 based on the signal, and the electromagnetic switching valve 17 switches from a state in which the flow path is closed, and High-pressure hydraulic oil supplied from the hydraulic pump 16 flows into the hydraulic cylinder 11. When the hydraulic pressure of the hydraulic oil is introduced into the hydraulic cylinder 11, the hydraulic piston 11a is pushed to move rightward in the figure, and in conjunction with this, the concrete piston 1a also moves rightward in the figure to move the concrete cylinder 11a. The concrete in 1 is extruded.

At the same time, the hydraulic oil filled in the space 11c is pushed out from the hydraulic cylinder 11 by pushing the hydraulic piston 11a, and flows into the space 12c on the hydraulic cylinder 12 side through the communication passage 15. . When the hydraulic oil flows into the space 12c, the hydraulic piston 12a is pushed and moves to the left in the figure, and in conjunction with this, the concrete piston 2a also moves to the left in the figure to move the chamber 4 into the concrete cylinder 2. Concrete is inhaled from.

The concrete extruded from the concrete cylinder 1 flows into the concrete pipe 5 through the communication switching pipe 6, and is discharged from a nozzle (not shown) provided at the end of the boom.

When the hydraulic piston 11a reaches the stroke end, the stroke end detection sensor 13 detects this. When this detection result is input to the control unit 25, a switching signal is output to each of the electromagnetic switching valves 10 and 17 based on the detection result, and the electromagnetic switching valve 17 is closed and the electromagnetic switching valve 10 is switched. The high-pressure hydraulic oil supplied from the compressor flows into the hydraulic cylinder 7. When the hydraulic oil pressure is introduced into the hydraulic cylinder 7, the hydraulic piston 7
is pushed upward in the drawing, and the communication switching pipe 6 connected to the hydraulic piston 7a via the piston rod 7b is switched from the concrete cylinder 1 side to the concrete cylinder 2 side.

When the hydraulic piston 7a reaches the stroke end, the stroke end detection sensor 8 detects this. When the detection result is input to the control unit 25, a switching signal is output to the electromagnetic switching valve 17 based on the detection result, and the introduction direction is switched from the state in which the electromagnetic switching valve 17 is closed to the direction opposite to the previous direction, High-pressure hydraulic oil flows into the hydraulic cylinder 12. Thereafter, the same operation as above is repeated, and concrete is discharged from the end of the boom.

When a concrete structure is constructed using the above-described concrete transfer device, when concrete is poured into a space having a complicated shape or a relatively small space that requires higher precision, the concrete from the end of the boom is required. It is necessary to reduce the discharge amount per unit time. This is because if the discharge rate is large, the concrete after the casting is pitted or the concrete is poured more than necessary, resulting in inferior completion after the construction.

Therefore, in the above-described concrete conveying apparatus, the discharge rate of concrete is reduced by lowering the rotation speed of the hydraulic pump 16 and reducing the discharge capacity of the hydraulic oil, and lowering the drive speed of the concrete cylinder.

[0010]

In the above concrete conveying device, the switching operation of the communication switching pipe 6 is performed by using the hydraulic pressure generated by the hydraulic pump 16 similarly to the concrete cylinders 1 and 2, so that the concrete If the rotation speed of the hydraulic pump 16 is reduced or the discharge capacity is reduced in order to reduce the discharge amount, the switching operation itself of the communication switching pipe 6 also becomes slow.

Even if the switching operation of the communication switching pipe 6 is delayed, there is no particular problem unless the height difference between the concrete conveying device and the discharge position of the boom tip is large. However, if the boom is raised high and concrete is to be poured into high places, the difference in elevation will be large, and concrete will flow backward during the switching operation that does not receive the discharge pressure. However, there is a possibility that concrete will hardly be discharged from the end of the boom.

In order to prevent such a situation, there is an example in which the switching operation of the communication switching pipe 6 is performed by using an independent driving means. However, in this case, the structure of the concrete conveying device becomes complicated and the durability is reduced. Is expected to cause problems.
Further, there is a concern that the cost of the apparatus itself may increase due to the complicated structure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a concrete transfer device capable of placing concrete at a high place without any trouble, and having high durability and a large cost merit. The purpose is to provide a concrete pump truck to be mounted.

[0014]

As means for solving the above-mentioned problems, a fluid conveying device and a concrete pump truck having the following structures are employed. That is, the fluid transporting device according to claim 1 of the present invention is supported so as to be selectively connectable to any of a plurality of transporting means for sucking / discharging a fluid such as concrete or earth and sand, and any of the transporting means. A switching pipe, a switching pipe driving cylinder for driving the switching pipe and selectively connecting the switching pipe to one of the transporting means, and a transporting means driving individually provided in each of the transporting means for sucking / discharging the fluid. A cylinder, a hydraulic pump having a variable discharge amount for pressurizing and conveying hydraulic oil to operate each of the drive cylinders, and a discharge amount changing unit for changing a discharge amount of the hydraulic pump; A fluid transporting device that continuously transports the fluid by switching the introduction in a timely manner, and increasing the discharge amount of the hydraulic pump when introducing hydraulic pressure to the switching pipe drive cylinder. Characterized in that to increase the driving speed of the switching 換管 cylinder.

In the present invention, when the hydraulic pressure is introduced into the switching pipe driving cylinder to perform the switching operation of the switching pipe, the discharge speed of the hydraulic pump is increased to increase the driving speed of the switching pipe driving cylinder. Is quickly performed. Thereby, even when the height difference between the concrete conveyance device and the discharge position is large, the backflow of the concrete can be suppressed and the discharge can be performed smoothly. Moreover, since there is no independent driving means for performing the switching operation of the communication switching pipe and the structure is simple, not only the durability is excellent but also the cost merit of the apparatus itself is great.

According to a second aspect of the present invention, in the fluid transporting apparatus according to the first aspect of the present invention, the completion of the discharging operation of the transport unit driving cylinder is detected, and the discharge amount changing unit is operated in response to the detection. Thus, the discharge amount of the hydraulic pump is increased.

In the present invention, the discharge amount changing means is actuated upon completion of the discharge operation in the transport means driving cylinder, so that a wasteful suction operation inviting the concrete cylinder to flow backward by the concrete cylinder is prevented. As a result, the discharge operation can be performed smoothly.

According to a third aspect of the present invention, in the fluid transport device according to the second aspect, the completion of the switching operation of the switching pipe by the switching pipe driving cylinder is detected, and the discharge amount is triggered by this detection. The discharge amount of the hydraulic pump is returned to the previous state by operating the changing means.

In the present invention, when the switching operation of the switching pipe is completed by the switching pipe driving cylinder, the discharge amount changing means is operated to prevent the concrete cylinder from performing a wasteful discharging operation. Can be performed smoothly.

According to a fourth aspect of the present invention, there is provided the fluid transporting apparatus according to the first, second or third aspect, wherein the hydraulic pump is of a variable displacement type.

In the present invention, by employing a variable displacement hydraulic pump capable of instantaneously changing the displacement, the linkage between the switching pipe drive cylinder and the transfer means drive cylinder can be carried out in a timely manner. .

A concrete pump truck according to claim 5 is
A fluid transport device according to claim 1, 2, 3, 4, or 5 is provided.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of the structure of a concrete conveying device mounted on a concrete pump truck as an embodiment according to the present invention. In FIG.
Is a concrete cylinder, 3 is a hopper into which concrete is put, 4 is a chamber communicating with the hopper 3, 5 is a concrete pipe which communicates with one of the concrete cylinders 1 and 2 and serves as a concrete transport path, and 6 is a concrete cylinder. One of the two is selectively connected to the concrete pipe 5 and the other is connected to the chamber 4.
, A hydraulic cylinder for driving the communication switching pipe 6, 8 and 9, stroke end detection sensors for detecting the state of the hydraulic cylinder 7, 10
Is an electromagnetic switching valve for switching the direction of introducing hydraulic pressure to the hydraulic cylinder 7.

Reference numerals 11 and 12 denote hydraulic cylinders for driving the concrete cylinders 1 and 2 respectively.
14 is a stroke end detection sensor for detecting the state of the hydraulic cylinders 11 and 12;
A swash plate piston type hydraulic pump 16 pressurizes and conveys hydraulic oil to operate the hydraulic cylinders 11, 12 and the hydraulic cylinder 7, and 17 a hydraulic cylinder 1
An electromagnetic switching valve for selectively switching the direction of introducing hydraulic pressure to the hydraulic pumps 1 and 12, a relief valve 18 for limiting the amount of hydraulic pressure generated by the hydraulic pump 16, and an electromagnetic switching valve 19 for interrupting the operation of the relief valve 18. It is a valve.

Further, reference numeral 20 denotes a displacement variable mechanism that changes the tilt angle of a swash plate (not shown) of the hydraulic pump 16 to change the discharge displacement, and 21 pressurizes hydraulic oil to operate the displacement variable mechanism 20. A constant displacement type hydraulic pump to be conveyed, 22 is a relief valve for limiting the magnitude of the hydraulic pressure generated by the hydraulic pump 21, 23 is an electromagnetic switching valve for interrupting the operation of the variable capacity mechanism 20, and 24 is a reservoir for operating oil. The storage reservoir 25 is a control unit that switches the electromagnetic switching valves 10, 19, and 23 based on the detection results of the stroke end detection sensors. Note that the solid line shown in the figure indicates a pipe through which hydraulic oil flows, and the broken line indicates a signal line for transmitting an electric signal.

Concrete cylinder 1 and hydraulic cylinder 1
1 is a concrete piston 1a and a hydraulic piston 11a
Are connected via a piston rod 26, and when hydraulic pressure is introduced into the hydraulic cylinder 11 and the hydraulic piston 11a is pushed, the concrete piston 1
a moves in the same direction.

Concrete cylinder 2 and hydraulic cylinder 1
Similarly, the concrete piston 2a and the hydraulic piston 12a are connected via a piston rod 27. When hydraulic pressure is introduced into the hydraulic cylinder 12 and the hydraulic piston 12a is pushed, the concrete piston 2a and the hydraulic piston 12a are interlocked. The concrete piston 2a moves in the same direction.

Inside the hydraulic cylinder 11, two spaces are formed with a hydraulic piston 11a interposed therebetween. One space 11b is supplied with hydraulic oil from a hydraulic pump 16, while the other space 11c is supplied with hydraulic oil. Hydraulic fluid is filled separately.

Two spaces are also formed inside the hydraulic cylinder 12 with a hydraulic piston 12a interposed therebetween. One space 12b is supplied with hydraulic oil from a hydraulic pump 16, while the other space 12c is provided with hydraulic oil. Hydraulic fluid is filled separately.

The space 11c on the hydraulic cylinder 11 side and the space 12c on the hydraulic cylinder 12 side communicate with each other by a communication passage 15 so that hydraulic oil can flow in and out. When the piston 11a is moved rightward in the drawing, the working oil filled in the space 11c flows into the space 12c on the hydraulic cylinder 12 side through the communication path 15, and moves the hydraulic piston 12a leftward in the drawing. ing.

The communication switching pipe 6 has one end 6a rotatably connected to the concrete pipe 5, and the other bent end 6b is rotated about the one end 6a so that the discharge port 1b of the concrete cylinder 1 or concrete. It is configured to selectively communicate with one of the discharge ports 2b of the cylinder 1. The rotation of the communication switching pipe 6 is performed by pushing and pulling a tab 6 c attached outside the one end 6 a by driving the hydraulic cylinder 7.

The manner of operation of the concrete transport device configured as described above will be described. When a signal instructing the start of operation is input to the control unit 25, a switching signal is output to the electromagnetic switching valve 17 based on the signal, and the electromagnetic switching valve 17 switches from a state in which the flow path is closed, and the hydraulic pump 16 The high-pressure hydraulic oil supplied from the compressor flows into the hydraulic cylinder 11.
When the hydraulic pressure of the hydraulic oil is introduced into the hydraulic cylinder 11, the hydraulic piston 11a is pushed to move rightward in the figure, and in conjunction with this, the concrete piston 1a also moves rightward in the figure to move the concrete cylinder 11a. The concrete in 1 is extruded.

At the same time, the hydraulic oil filled in the space 11c is pushed out from the hydraulic cylinder 11 by pushing the hydraulic piston 11a, and flows into the space 12c on the hydraulic cylinder 12 side through the communication passage 15. . When the hydraulic oil flows into the space 12c, the hydraulic piston 12a is pushed and moves to the left in the figure, and in conjunction with this, the concrete piston 2a also moves to the left in the figure to move the chamber 4 into the concrete cylinder 2. Concrete is inhaled from.

The concrete extruded from the concrete cylinder 1 flows into the concrete pipe 5 through the communication switching pipe 6, and is discharged from a nozzle (not shown) provided at the end of the boom.

When the hydraulic piston 11a reaches the stroke end, the stroke end detection sensor 13 detects this. When this detection result is input to the control unit 15, a switching signal is output to each of the electromagnetic switching valves 10 and 17 based on the detection result, and the electromagnetic switching valve 17 is closed and the electromagnetic switching valve 10 is switched. The high-pressure hydraulic oil supplied from the compressor flows into the hydraulic cylinder 7. When the hydraulic oil pressure is introduced into the hydraulic cylinder 7, the hydraulic piston 7
is pushed upward in the drawing, and the communication switching pipe 6 connected to the hydraulic piston 7a via the piston rod 7b is switched from the concrete cylinder 1 side to the concrete cylinder 2 side.

At the same time, a switching signal is also output to the electromagnetic switching valve 23, the electromagnetic switching valve 23 switches from a state in which the flow path is closed, and the high-pressure hydraulic oil supplied from the hydraulic pump 21 is variable in capacity. It flows into the mechanism 20. When the hydraulic pressure of the hydraulic oil is introduced into the capacity variable mechanism 20, the tilt angle of the swash plate built in the hydraulic pump 16 changes, and the discharge capacity increases. When the discharge capacity of the hydraulic pump 16 increases, the amount of hydraulic oil flowing into the hydraulic cylinder 7 per unit time increases, so that the driving speed of the hydraulic cylinder 7 increases and the switching operation of the communication switching pipe 6 is performed. It will be done quickly.

When the hydraulic piston 7a reaches the stroke end, the stroke end detection sensor 8 detects this. When the detection result is input to the control unit 25, a switching signal is output to the electromagnetic switching valve 17 based on the detection result, and the introduction direction is switched from the state in which the electromagnetic switching valve 17 is closed to the direction opposite to the previous direction, High-pressure hydraulic oil flows into the hydraulic cylinder 12.

At the same time, a switching signal is also output to the electromagnetic switching valve 23, the electromagnetic switching valve 23 switches to a state in which the flow path is closed, and the supply of hydraulic oil to the variable displacement mechanism 20 is cut off. . When the supply of hydraulic oil is cut off, the hydraulic pump 16
Then, the tilt angle of the swash plate built in is returned to the original state, and the discharge capacity is restored to the original size. Since the arrangement of the communication switching pipe 6 must be maintained, no switching is instructed to the electromagnetic switching valve 10. Thereafter, the same operation as above is repeated, and concrete is discharged from the end of the boom.

In the above concrete transport device,
Even when the boom is raised high and the height difference from the discharge position at the end of the boom is increased, since the switching operation of the communication switching pipe 6 is performed quickly, the backflow of the concrete is less likely to occur. Even if it is squeezed, it can be driven to a high place without any trouble.

Further, the present invention does not employ an independent driving means for performing the switching operation of the communication switching pipe 6, and the structure itself is not significantly different from the conventional structure, so that the apparatus is of course excellent in durability, There is no cost per se.

Although the swash plate piston type variable displacement hydraulic pump is employed as the hydraulic pump 16 in the above embodiment, other variable displacement hydraulic pumps such as a swash shaft pump may be employed. . In the above embodiment, the capacity of the hydraulic pump 16 is increased by introducing hydraulic pressure to the capacity changing mechanism 20, but the capacity of the hydraulic pump 16 is reduced by cutting off the introduction of hydraulic pressure to the capacity changing mechanism 20. A structure for increasing the size may be adopted. In this case, the opening / closing operation of the electromagnetic switching valve 23 needs to be reversed.

In the above-described embodiment, the discharge amount of the hydraulic pump 16 is controlled by changing the control hydraulic pressure from the outside. However, as shown in FIG. Discharge amount control unit 3 of pump 16
Alternatively, an electrical control signal may be directly input to 0 to control the discharge amount.

In the above embodiment, the switching operation of the communication switching pipe 6 is accelerated by changing the capacity of the hydraulic pump 16. However, the switching operation can be accelerated by increasing the rotation speed of the hydraulic pump 16. .

Further, in the above-described embodiment, the concrete transport device mounted on the concrete pump truck has been described. However, if this concrete pump truck is used, even when the height difference between the ground and the discharge position of the boom tip is large, the concrete can be transferred. Discharge can be performed smoothly by suppressing backflow. Needless to say, the fluid conveying device according to the present invention can be used for conveying earth, sand and other fluids in addition to concrete.

[0045]

As described above, according to the present invention,
When hydraulic pressure is introduced into the switching pipe driving cylinder to perform the switching pipe switching operation, the switching pipe switching operation is rapidly performed by increasing the discharge amount of the hydraulic pump and increasing the driving speed of the switching pipe driving cylinder. . Thereby, even when the height difference between the concrete conveying device and the discharge position at the end of the boom is large, the concrete can be prevented from flowing backward and the discharge can be performed smoothly. In addition, since there is no independent driving means for performing the switching operation of the switching tube and the structure is simple, not only the durability is excellent but also the cost merit of the apparatus itself is great.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a structure of a concrete transport device according to a fluid transport device of the present invention.

FIG. 2 is a schematic configuration diagram in a case where the discharge amount control by a hydraulic pump is an electronic control type in the concrete conveying device of FIG. 1;

FIG. 3 is a schematic configuration diagram showing a structure of a conventional concrete transport device.

[Explanation of symbols]

 1, concrete cylinder (transportation means) 6 communication switching pipe (switching pipe) 7 hydraulic cylinder (switching pipe drive cylinder) 8, 9 stroke end detection sensor 11, 12 hydraulic cylinder (transportation means drive cylinder) 13, 14 stroke end detection Sensor 16 Hydraulic pump 20 Variable capacity mechanism (discharge amount changing means) 23 Electromagnetic switching valve 25 Control unit

Claims (5)

[Claims] 1. Inhalation of fluids such as concrete and earth and sand
A plurality of transporting means for discharging, a switching pipe supported selectively connectable to any of the transporting means, and a switching pipe driving for driving the switching pipe to selectively connect to any of the transporting means A cylinder, a transporting unit drive cylinder individually provided in each of the transporting units for sucking / discharging the fluid, a variable discharge hydraulic pump for pressurizing and transporting hydraulic oil to operate each of the driving cylinders, A discharge amount changing means for changing a discharge amount of the hydraulic pump, a fluid transport device for continuously transporting the fluid by appropriately switching hydraulic pressure introduction to each of the drive cylinders; A fluid transporting device, wherein when the hydraulic pressure is introduced into the tube driving cylinder, the discharge amount of the hydraulic pump is increased to increase the driving speed of the switching tube cylinder. 2. The discharge amount of said hydraulic pump is increased by detecting the completion of a discharge operation in said transfer means drive cylinder and activating said discharge amount changing means in response to said detection. Fluid transport device. 3. Detecting the completion of the switching operation of the switching pipe by the switching pipe driving cylinder, triggering the discharge amount changing means to return the discharge amount of the hydraulic pump to the previous state. The fluid conveying device according to claim 2, wherein 4. The fluid transport device according to claim 1, wherein the hydraulic pump is of a variable displacement type. 5. A concrete pump truck comprising the fluid conveying device according to claim 1, 2, 3 or 4.