Concrete pump

Abstract

The objective is to provide a concrete pump that can continue to be used even after a malfunction has occurred and the malfunction has been identified. [Solution] The concrete pump according to the present invention comprises a piston-type concrete pump that supplies fresh concrete to a discharge section, a detection section that detects the operation of the piston-type concrete pump, and an emergency mode switch. The piston-type concrete pump comprises a concrete cylinder having a discharge port end capable of discharging the fresh concrete it contains, a piston that discharges the fresh concrete contained in the concrete cylinder from the discharge port end, a drive cylinder for driving the piston, and a control unit that controls the piston-type concrete pump. The emergency mode switch is a switch for operating the control unit in emergency mode.

Description

Technical Field

[0001] The present invention relates to a concrete pump used in a concrete pump truck or the like for placing fresh concrete in a building or the like.

Background Art

[0002] Conventionally, a concrete pump capable of supplying fresh concrete has been known (see Patent Document 1). As shown in FIG. 5, this concrete pump 100 includes a pair of drive cylinders 101 and a pair of conveying cylinders 102, pistons 103 respectively disposed in the drive cylinders 101, a conveying piston 104 disposed in each conveying cylinder 102, and a piston rod 105 connecting the corresponding piston 103 and the conveying piston 104. Further, the concrete pump 100 includes cylinder switching sensors 106 and 107 respectively disposed at intervals from the piston rod side end and the bottom side end of each drive cylinder 101. In the concrete pump 100, when the cylinder switching sensors 106 and 107 detect the piston 103, the moving direction of the piston 103 is switched based on the signals output from the cylinder switching sensors 106 and 107, thereby supplying fresh concrete or the like.

[0003] Also, during normal operation, this concrete pump 100 calculates the stroke prediction time of the piston 103 based on the signals from the cylinder switching sensors 106 and 107 and files it in a data memory. When the cylinder switching sensors 106 and 107 fail, the moving direction of the piston 103 in each drive cylinder 101 is switched based on this stroke prediction time. Thereby, even if a failure occurs in the cylinder switching sensors 106 and 107, the supply of fresh concrete can be continued.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] However, in the concrete pump 100 described above, when the cylinder switching sensors 106 and 107 fail, the system automatically switches to operation using the stroke prediction time. As a result, operators may continue to use the concrete pump 100 without noticing the malfunction, and the malfunction may be left unaddressed for a long period of time.

[0006] Therefore, the object of the present invention is to provide a concrete pump that can continue to be used after a malfunction has occurred and the malfunction has been identified. [Means for solving the problem]

[0007] The concrete pump of the present invention is A piston-type concrete pump that supplies ready-mix concrete to the discharge section, A detection unit that detects the operation of the piston-type concrete pump, Equipped with an emergency mode switch, The aforementioned piston-type concrete pump is A concrete cylinder having a discharge port end capable of discharging the contained ready-mixed concrete, A piston that discharges the ready-mixed concrete contained in the concrete cylinder from the discharge port end, A drive cylinder for driving the piston, It includes a control unit for controlling the piston-type concrete pump, The emergency mode switch is a switch for operating the control unit in emergency mode.

[0008] With this configuration, if a malfunction (such as an operational abnormality) is detected by the detection unit during the ready-mix concrete supply operation, the operator can press the emergency mode switch to switch the piston-type concrete pump to emergency mode, thereby allowing the ready-mix concrete supply operation to continue. In other words, with this concrete pump, when a malfunction occurs, the operator can be aware of the malfunction and continue using the pump.

[0009] The concrete pump is equipped with a timer, The piston-type concrete pump has a pair of concrete cylinders, a pair of pistons, and a pair of drive cylinders, and also has a switching valve that switches the concrete cylinder connected to the discharge section by switching the connection position. The detection unit is capable of detecting whether the switching valve is located at each connection position with the pair of concrete cylinders. The control unit may, based on the timer, determine the switching timing of the concrete cylinder connected to the discharge section of the switching valve when the emergency mode switch is operated due to a malfunction of the detection unit detected based on the detection of the detection unit, thereby entering the emergency mode.

[0010] With this configuration, by switching to emergency mode, the switching operation (switching timing) of the switching valve is controlled based on the time measured by the timer. Therefore, even if the detection unit capable of detecting the position of the switching valve at each connection point malfunctions, the ready-mix concrete supply operation can continue.

[0011] in this case, The control unit may stop the piston-type concrete pump when it detects a malfunction of the switching valve based on the detection unit's detection.

[0012] This ensures that the piston-type concrete pump can be reliably stopped in the event of a switching valve failure.

[0013] Furthermore, the concrete pump is Power source and The system comprises a hydraulic pump driven by the aforementioned power source, The aforementioned drive cylinder is a hydraulic cylinder connected to the hydraulic pump, The detection unit is capable of detecting the hydraulic pressure of the hydraulic cylinder, The control unit may set the rotational speed of the drive source to a predetermined rotational speed when the emergency mode switch is operated and the emergency mode is activated based on the detection of the detection unit, thereby detecting a malfunction in the detection unit.

[0014] With this configuration, by switching to emergency mode, the rotation speed of the drive source is controlled without relying on the detection of hydraulic pressure in the hydraulic cylinder. Therefore, even if the detection unit capable of detecting the hydraulic pressure in the hydraulic cylinder fails, the ready-mix concrete supply operation can continue.

[0015] Furthermore, in the aforementioned concrete pump, The aforementioned piston is Within the concrete cylinder, a discharge head is provided which is capable of moving toward one side toward the discharge port end and moving toward the other side toward the discharge port end, The drive cylinder includes a drive head that is capable of moving the discharge head to one side within the drive cylinder, and moving the discharge head to the other side within the drive cylinder, The detection unit, A first detection unit detects that the drive head is in a one-side switching position where it switches from moving to one side to moving to the other side, The drive head has a second detection unit that detects the drive head at a deceleration position that is on one side of the center of the movement stroke from the other-side switching position, where the drive head switches from movement to the other side to movement to the one-side switching position, and on the other side of the one-side switching position. The control unit, When the drive head moves to one side, when the second detection unit detects the drive head, the moving speed of the drive head is decelerated, and when the first detection unit detects the drive head, the moving direction of the drive head is switched from one side to the other side. At the same time, When a failure of the second detection unit is detected based on the detections of the first detection unit and the second detection unit, and the emergency mode switch is operated to enter the emergency mode, it may not be necessary to control the movement of the drive head based on the detection of the second detection unit.

[0016] According to such a configuration, by switching to the emergency mode, deceleration based on the detection of the second detection unit is not performed during the movement of the drive head to one side, and the movement direction of the drive head is switched based on the detection by the first detection unit. Therefore, even if the second detection unit fails, the supply operation of fresh concrete can be continued.

[0017] Also, the concrete pump includes a timer. The piston In the concrete cylinder, there is a discharge head capable of moving to one side approaching the discharge port end and moving to the other side away from the discharge port end, In the drive cylinder, there is a drive head capable of moving to one side in the drive cylinder to move the discharge head to one side and moving to the other side in the drive cylinder to move the discharge head to the other side. The detection unit A first detection unit that detects that the drive head is located at a one-side switching position where it switches from moving to one side to moving to the other side, A second detection unit that detects the drive head at a deceleration position on one side of the central position of the movement stroke from the other-side switching position where the drive head switches from moving to the other side to moving to one side to the one-side switching position and on the other side of the one-side switching position. The control unit When the drive head moves to one side, the second detection unit reduces the speed of the drive head when it detects the drive head, and the first detection unit switches the direction of movement of the drive head from one side to the other when it detects the drive head, When a malfunction of the first detection unit is detected based on the time measured by the timer and the detection by the first detection unit, and the emergency mode switch is operated to enter the emergency mode, the direction of movement of the drive head may be switched from one side to the other based on the detection by the second detection unit.

[0018] With this configuration, when the system is switched to emergency mode, the direction of movement of the drive head is switched based on the detection of the second detection unit when the drive head moves to one side. Therefore, even if the first detection unit fails, the ready-mix concrete supply operation can continue.

[0019] Furthermore, the concrete pump is equipped with a timer, When the emergency mode is activated, the control unit may determine, based on the timer, the timing at which the second detection unit detects the drive head during its movement to one side and then switches the direction of movement from one side to the other.

[0020] With this configuration, when the system switches to emergency mode, the direction of movement of the drive head is switched based on the time measured by a timer triggered by the detection of the drive head by the second detection unit (i.e., after a predetermined time has elapsed) when the drive head moves to one side. This suppresses the reduction in the stroke length of the drive head, and thereby suppresses the reduction in the amount of ready-mixed concrete supplied to the discharge unit (more specifically, the amount supplied per unit time) when the system switches to emergency mode.

[0021] Furthermore, the concrete pump is equipped with a timer, The aforementioned piston is Within the concrete cylinder, a discharge head is provided which is capable of moving toward one side toward the discharge port end and moving toward the other side toward the discharge port end, The drive cylinder includes a drive head that is capable of moving the discharge head to one side within the drive cylinder, and moving the discharge head to the other side within the drive cylinder, The detection unit, A first detection unit detects that the drive head is in a one-side switching position where it switches from moving to one side to moving to the other side, The drive head has a second detection unit that detects the drive head at a deceleration position that is on one side of the center of the movement stroke from the other-side switching position, where the drive head switches from movement to the other side to movement to the one-side switching position, and on the other side of the one-side switching position. The control unit, When the drive head moves to one side, the second detection unit reduces the speed of the drive head when it detects the drive head, and the first detection unit switches the direction of movement of the drive head from one side to the other when it detects the drive head, When the emergency mode switch is operated and the emergency mode is activated based on the time measured by the timer, the detection by the first detection unit, and the detection by the second detection unit, the timing at which the direction of movement of the drive head is switched from one side to the other may be determined based on the timer, from the moment the direction of movement of the drive head is switched from the other side to the one side.

[0022] With this configuration, when the system switches to emergency mode, the movement direction of the drive head is switched from one side to the other based on the elapsed time since the movement direction was switched from the other side to the other side. Therefore, even if both the first and second detection units fail, the ready-mix concrete supply operation can continue.

[0023] Furthermore, the concrete pump is The piston-type concrete pump is equipped with a drive source, The detection unit is capable of detecting the rotational speed of the drive source, The control unit, The rotational speed of the drive source is controlled so that the rotational speed instruction from the control unit to the drive source matches the rotational speed detected by the detection unit, When a malfunction of the detection unit is detected based on the detection unit's detection, and the emergency mode switch is operated to enter the emergency mode, the rotational speed of the drive source may be controlled by the rotational speed instruction without relying on the detection unit's detection.

[0024] With this configuration, by switching to emergency mode, the rotation speed of the drive source is controlled based on a rotation speed instruction (instruction signal) output from the control unit, rather than on the actual rotation speed of the drive source detected by the detection unit (i.e., not on feedback control). Therefore, even if the detection unit capable of detecting the rotation speed of the drive source fails, the ready-mix concrete supply operation can continue.

[0025] Furthermore, the concrete pump is equipped with a notification unit, The control unit may cause the notification unit to notify when a fault is detected based on the detection unit's detection.

[0026] With this configuration, operators and others can more easily and reliably grasp the occurrence of a malfunction through notifications from the notification unit, thereby enabling a more reliable switch to emergency mode when a malfunction occurs. [Effects of the Invention]

[0027] Based on the above, the present invention provides a concrete pump that can continue to be used after recognizing a malfunction. [Brief explanation of the drawing]

[0028] [Figure 1] Figure 1 is a side view of a concrete pump truck according to this embodiment. [Figure 2]Figure 2 is a conceptual diagram showing the configuration of the concrete pump installed in the concrete pump truck. [Figure 3] Figure 3 is a plan view of the control panel of the concrete pump truck. [Figure 4] Figure 4 is a perspective view of the operating section. [Figure 5] Figure 5 is a conceptual diagram showing the configuration of a conventional concrete pump. [Modes for carrying out the invention]

[0029] The following describes one embodiment of the present invention with reference to Figures 1 to 4.

[0030] As shown in Figures 1 and 2, the concrete pump 3 of this embodiment is mounted on a concrete pump truck 1. This concrete pump truck 1 comprises a vehicle frame F extending in the longitudinal direction of the vehicle, a subframe (not shown) provided above the vehicle frame F, a boom device 2 mounted on the subframe, a concrete pump 3 mounted on the subframe, and a hopper 4 into which ready-mix concrete C (see Figure 2) is fed from a concrete mixer truck or the like. This hopper 4 is the part into which ready-mix concrete C is fed by the concrete mixer truck, and is located at the rear of the vehicle (behind the concrete pump 3) with an open top. The concrete pump truck 1 also includes an engine (drive source) E, which is the power source for driving. The concrete pump truck 1 of this embodiment includes an operating unit (in this example, a radio control transmitter) 5 for operating the boom device 2 and the concrete pump 3 (see Figure 3).

[0031] The boom device 2 has a boom 20 in which multiple beams 21a to 21d are connected in a bendable manner, and concrete pumping pipes 22 attached to the side of the boom 20, and is used to extend the boom 20 by a hydraulic cylinder to pour ready-mix concrete C at a location away from the vehicle body. The base end of the boom 20 (beam 21a on the vehicle body side) is rotatable (swivels) around an axis perpendicular to the vehicle body. In the concrete pump truck 1, the boom-closed state, in which the boom 20 is folded as shown in Figure 1, is the state in which it can travel on public roads.

[0032] The concrete pump 3 pumps the ready-mix concrete C, which has been fed from the concrete mixer truck into the hopper 4, into the concrete pumping pipe 22 and discharges it from the end opening (discharge section) of the concrete pumping pipe 22.

[0033] Specifically, the concrete pump 3 comprises a pump body (piston-type concrete pump) 30 that pumps (supplies) ready-mix concrete C to the end opening of the concrete pumping pipe 22, a detection unit 6 that detects the operation of the pump body 30, and an emergency mode switch S2 for operating the control unit 34 of the pump body 30 in emergency mode (see Figure 3). In the concrete pump 3 of this embodiment, the emergency mode switch S2 is located on the operation unit 5. The concrete pump 3 also includes a timer T. In the concrete pump 3 of this embodiment, the timer T is located on the control unit 34 of the pump body 30.

[0034] The pump body 30 comprises a concrete cylinder 31 having a one-end opening (discharge port end) 311 from which the contained ready-mix concrete C can be discharged, a piston 33 that discharges the ready-mix concrete C contained in the concrete cylinder 31 from the one-end opening 311, a drive cylinder 32 for driving the piston 33, and a control unit 34 for controlling the pump body 30. In the pump body 30 of this embodiment, the set of concrete cylinder 31, piston 33, and drive cylinder 32 is arranged in pairs on the left and right in the vehicle width direction. The pump body 30 has a switching valve 35 that switches the concrete cylinder 31 connected to the concrete pumping pipe 22 (end opening) by switching the connection position. The pump body 30 also has a hydraulic system 36 for driving the drive cylinder 32.

[0035] The concrete cylinder 31 is cylindrical in shape, extending in the vehicle length direction and open at both ends. It has a one-end opening (discharge port end) 311 at one end (right side in Figure 2) and a other-end opening 312 at the other end (left side in Figure 2). Multiple concrete cylinders 31 are arranged on the pump body 30. In the pump body 30 of this embodiment, two (a pair) concrete cylinders 31 are arranged parallel to each other in the vehicle width direction. These concrete cylinders 31 are mounted on the subframe together with the drive cylinder 32.

[0036] The drive cylinder 32 is cylindrical in shape and extends in the direction of the vehicle's length, and is configured to drive the piston 33. The drive cylinder 32 in this embodiment is a so-called hydraulic cylinder, and drives (reciprocates) the piston 33 when hydraulic fluid is supplied to it. Multiple drive cylinders 32 are arranged (the same number as the number of concrete cylinders 31). Each drive cylinder 32 is positioned in front of the corresponding concrete cylinder 31 and coaxial with the concrete cylinder 31.

[0037] Each drive cylinder 32 has a hydraulic fluid inlet / outlet 321 at the concrete cylinder 31 side end (one side end) to which hydraulic fluid is supplied. The hydraulic fluid supplied to the drive cylinder 32 is supplied to the inside of the drive cylinder 32 through the hydraulic fluid inlet / outlet 321 by the hydraulic system 36, causing the piston 33 to retract relative to the drive cylinder 32 (i.e., to move toward the other side end of the drive cylinder 32).

[0038] The piston 33 includes a discharge head 331 that can move in one direction towards one end opening 311 within the concrete cylinder 31, and in the other direction away from one end opening 311 (i.e., towards the other end opening 312), and a drive head 332 that can move in one direction within the drive cylinder 32 to move the discharge head 331 in one direction, and in the other direction within the drive cylinder 32 to move the discharge head 331 in the other direction. The piston 33 also includes a rod 333 that extends axially in the corresponding concrete cylinder 31 and drive cylinder 32 and connects the discharge head 331 and the drive head 332.

[0039] The discharge head 331 in this embodiment is cylindrical in shape, having an outer diameter that corresponds to the inner diameter of the concrete cylinder 31. The drive head 332 in this embodiment is also cylindrical in shape, having an outer diameter that corresponds to the inner diameter of the drive cylinder 32.

[0040] In the concrete cylinder 31, drive cylinder 32, and piston 33 configured as described above, each drive cylinder 32 alternately extends and retracts (moves forward and backward) the piston 33. As a result, the discharge heads 331 reciprocate in opposite phases within each concrete cylinder 31.

[0041] The switching valve 35 is positioned within the hopper 4 so as to be able to swing open or cover the one-end opening 311 of each concrete cylinder 31. This switching valve 35 connects the base end of the concrete pumping pipe 22, which is attached to the side of the boom 20, to the one-end opening 311 of each concrete cylinder 31. Specifically, the switching valve 35 is a curved pipe-shaped member (S-valve) that switches its position between the first position P1 and the second position P2 described below by swinging.

[0042] In the first position P1, the base end of the concrete pumping pipe 22 is connected to one end opening 311 of one concrete cylinder 31A, while the one end opening 311 of the other concrete cylinder 31B is left open (shown by a solid line in Figure 2). In the second position P2, the base end of the concrete pumping pipe 22 is connected to one end opening 311 of the other concrete cylinder 31B, while the one end opening 311 of one concrete cylinder 31A is left open (shown by a dashed line in Figure 2).

[0043] When the switching valve 35 is in the first position P1, that is, when the one-end opening 311 of the other concrete cylinder 31B is not connected to the switching valve 35 (with the one-end opening 311 open), the discharge head 331 inside the concrete cylinder 31B moves to the other side, causing the concrete cylinder 31B to suck in the fresh concrete C located inside the hopper 4. Then, when the switching valve 35 swings to the second position P2, that is, when the one-end opening 311 of the other concrete cylinder 31B is connected to the switching valve 35 (with the one-end opening 311 covered), the discharge head 331 inside the concrete cylinder 31B moves to one side, causing the fresh concrete C to be pushed out of the concrete cylinder 31B into the switching valve 35.

[0044] On the other hand, when the switching valve 35 is in the second position P2, that is, when one end opening 311 of one concrete cylinder 31A is not connected to the switching valve 35 (with the one end opening 311 open), the discharge head 331 inside the concrete cylinder 31A moves to the other side, causing the concrete cylinder 31A to suck in the fresh concrete C located inside the hopper 4. Then, when the switching valve 35 swings to the first position P1, that is, when one end opening 311 of one concrete cylinder 31A is connected to the switching valve 35 (with the one end opening 311 covered), the discharge head 331 inside the concrete cylinder 31A moves to one side, causing the fresh concrete C to be pushed out of the concrete cylinder 31A to the switching valve 35.

[0045] In this way, the switching valve repeatedly switches its position (posture) between the first position P1 and the second position P2, and the reciprocating motion of the discharge head 331 in one concrete cylinder 31A and the reciprocating motion of the discharge head 331 in the other concrete cylinder 31B are repeated in opposite phases, thereby continuously pumping (supplying) fresh concrete C to the concrete pumping pipe 22.

[0046] The hydraulic system 36 includes an oil tank 361 for storing hydraulic fluid and a hydraulic pump 362 for pumping the hydraulic fluid stored in the oil tank 361 to each of the multiple drive cylinders 32. It also includes a block-shaped valve unit 363 with a built-in valve for controlling the flow of hydraulic fluid and hydraulic piping 364 connecting each of the multiple drive cylinders 32, the hydraulic pump 362, and the valve unit 363.

[0047] The hydraulic pump 362 is connected to the engine E of the concrete pump truck 1 and pumps hydraulic fluid using the driving force of the engine E as its power source.

[0048] The valve unit 363 switches between the drive cylinders 32 that are being driven (the ones being extended or retracted) from among a plurality of drive cylinders 32 that alternately extend and retract the piston 33. This valve unit 363 is positioned on the vehicle front side of the drive cylinders 32.

[0049] The hydraulic piping 364 is also connected to the oil tank 361. In this embodiment, the hydraulic piping 364 is equipped with pilot check valves 365 for venting air when pressurized oil is supplied to each drive cylinder 32. These pilot check valves 365 are located at one end and the other end of each drive cylinder 32, respectively.

[0050] The detection unit 6 includes a position sensor 61 capable of detecting the position of the switching valve 35, a hydraulic pressure sensor 62 capable of detecting the hydraulic pressure inside the drive cylinder 32 or the hydraulic system 36, a head-side end sensor 63 capable of detecting the drive head 332 at the other end of the drive cylinder 32, a rod-side end sensor 64 capable of detecting the drive head 332 at one end of the drive cylinder 32, and a rotation speed sensor 65 capable of detecting the rotation speed of the engine E.

[0051] The position sensor 61 is capable of detecting the position of the switching valve 35 at each connection position with the pair of concrete cylinders 31. Specifically, the position sensor 61 includes a first position sensor 611 that can detect when the switching valve 35 is in a first position P1 (i.e., when the cylinder-side engaging portion 35a of the switching valve 35 is in a connection position with one end opening 311 of one concrete cylinder 31A), and a second position sensor 612 that can detect when the switching valve 35 is in a second position P2 (i.e., when the cylinder-side engaging portion 35a of the switching valve 35 is in a connection position with one end opening 311 of the other concrete cylinder 31B).

[0052] The hydraulic sensor 62 can detect the hydraulic pressure of the hydraulic fluid in the drive cylinder 32. In the concrete pump 3 of this embodiment, the control unit 34 controls the torque (rotational speed) of the engine E based on the hydraulic pressure detected by the hydraulic sensor 62, and the hydraulic pressure changes according to this torque (rotational speed).

[0053] The head-side end sensor 63 can detect when the drive head 332 has reached the other-side switching position P3 (the position shown by the solid line in one of the drive cylinders 32 in Figure 2), where the direction of movement of the drive head 332 switches from the other side to the one side within the drive cylinder 32 (i.e., when the drive head 332 is positioned at the other-side switching position P3).

[0054] The rod-side end sensor 64 includes an end detection unit (first detection unit) 641 capable of detecting when the drive head 332 has reached a one-side switching position P4 (the position shown by the dashed line in one of the drive cylinders 32 in Figure 2) where the direction of movement of the drive head 332 switches from one side to the other (the drive head 332 is located at the one-side switching position P4), and a slow detection unit (second detection unit) 642 capable of detecting when the drive head 332 has reached a deceleration position P5 (the position shown by the double dashed line in one of the drive cylinders 32 in Figure 2) which is on one side of the center of the movement stroke of the drive head 332 (piston 33) from the one-side switching position P4 to the other-side switching position P3, and on the other side of the one-side switching position P4 (the drive head 332 is located at the deceleration position P5).

[0055] The control unit 5 has various switches and the like for operating the boom device 2 and concrete pump 3 of the concrete pump truck 1. In this embodiment, the control unit 5 is a remote control that can be used at a distance from the concrete pump truck 1.

[0056] As shown in Figures 3 and 4, the operation unit 5 includes a start switch (not shown) that, when operated (pressed in this embodiment), starts the boom device 2 and the concrete pump 3; an emergency stop switch S1 that, when operated (pressed in this embodiment), causes the engine E, boom device 2, and concrete pump 3 to make an emergency stop; and an emergency mode switch S2 that, when operated (pressed in this embodiment), switches to emergency mode, allowing the engine E, boom device 2, and concrete pump 3 to continue operating. The operation unit 5 also includes a notification unit 50 that, when the control unit 34 determines that a malfunction has occurred in the concrete pump 3 (more specifically, the detection unit 6) based on the detection results of the detection unit 6, notifies the operator or others based on a notification signal from the control unit 34. In this embodiment, the notification unit 50 consists of a buzzer 50a and a lamp 50b.

[0057] Furthermore, the control unit 5 includes a main power switch 51 for starting the boom device 2 and concrete pump 3 of the concrete pump truck 1, a pump start switch 52 for starting the ready-mix concrete pumping operation of the concrete pump 3, rotation speed switches 53a and 53b for increasing or decreasing the rotation speed of the engine E, discharge control switches 54a and 54b for increasing or decreasing the discharge amount of the concrete pump 3, right rotation switch 55a and left rotation switch 55b for rotating the boom device 2 left or right, beam luffing switches 56a to 56h for luffing and rotating each beam 21a to 21d, and boom speed control switches 57a and 57b for adjusting the operating speed of the boom device 2.

[0058] In normal mode (a mode in which the pump body 30 supplies ready-mix concrete C to the concrete pumping pipe 22 in normal operation), the control unit 34 controls the extension and retraction (forward and backward) of the piston 33 relative to the drive cylinder 32 by controlling the hydraulic pressure in the drive cylinder 32, thereby supplying ready-mix concrete C to the concrete pumping pipe 22. Specifically, this is done as follows:

[0059] The control unit 34 moves the stopped drive head 332 toward the other side, for example. When the head-side end sensor 63 detects the drive head 332 during this movement toward the other side, that is, when the drive head 332 reaches the other-side switching position P3, the control unit 34 switches the direction of movement of the drive head 332 from the other side to the one side, and moves the drive head 332 toward the one side from the other-side switching position P3 at a predetermined speed.

[0060] When the drive head moves to one side, the slow detection unit 642 detects the drive head 332, that is, when the drive head 332 reaches the deceleration position P5, the control unit 34 decelerates the movement speed of the drive head 332. Then, when the end detection unit 641 detects the drive head 332 after this deceleration, that is, when the drive head 332 reaches the one-side switching position P4, the control unit 34 switches the direction of movement of the drive head 332 from one side to the other side and moves the drive head 332 toward the other side at a predetermined speed.

[0061] In this manner, the control unit 34 causes the drive head 332 to repeatedly reciprocate between the other-side switching position P3 and the one-side switching position P4, thereby extending and retracting the piston 33 relative to the drive cylinder 32. As a result, the discharge head 331 reciprocates within the concrete cylinder 31, repeatedly drawing fresh concrete C from the hopper 4 into the concrete cylinder 31 and pushing (supplying) the fresh concrete C drawn into the concrete cylinder 31 to the switching valve 35.

[0062] Furthermore, in emergency mode (a mode in which ready-mix concrete C is supplied to the concrete pumping pipe 22 when a predetermined malfunction has occurred in the detection unit 6), the control unit 34 supplies ready-mix concrete C to the concrete pumping pipe 22 by controlling the extension and retraction (forward and backward) of the piston 33 relative to the drive cylinder 32, even while the predetermined malfunction is still present. Specifically, this is as follows.

[0063] When the control unit 34 detects a predetermined malfunction in the concrete pump 3 based on the detection result from the detection unit 6 (in this embodiment, when the control unit 34 determines that a predetermined malfunction has occurred in the detection unit 6 based on the detection result from the detection unit 6), it sends an alert signal to the operation unit 5 and stops the concrete pump 3. Then, when an operator operating the operation unit 5 operates the emergency mode switch S2 (in this embodiment, by pressing it) in response to the alert from the alert unit 50, the control unit 34 switches the mode of the concrete pump 3 from normal mode to emergency mode and then controls the concrete pump 3. The following describes this in more detail.

[0064] When ready-mixed concrete C is supplied to the concrete pumping pipe 22, the control unit 34 detects the switching valve 35 with one position sensor (e.g., first position sensor) 611 and switches the switching valve 35 to the other concrete cylinder 31B side. If the second position sensor 612 does not detect the switching valve 35 after a predetermined time or longer (i.e., after the standard number of seconds required for the switching valve 35 to swing between the one end openings 311), the control unit 34 switches the switching valve 35 to the one concrete cylinder 31A side. When the first position sensor 611 detects the switching valve 35, the control unit 34 performs control to switch the switching valve 35 back to the other concrete cylinder 31B side. If the second position sensor 612 does not detect the switching valve 35 for a predetermined period of time or longer after the switching of the switching valve 35 again, the control unit 34 determines that the second position sensor 612 is faulty (i.e., it determines that the problem is not due to foreign matter getting caught in the switching valve 35, but rather a fault in one of the position sensors 612), and transmits a notification signal to the operation unit 5.

[0065] At this time, when an operator or the like recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode and determines the completion of the switching operation of the switching valve 35 from one concrete cylinder 31A to the other concrete cylinder 31B based on the time measured by the timer T. More specifically, after the control unit 34 switches the switching valve 35 based on the detection by the first position sensor 611, it assumes (determines) that the switching valve 35 has moved to the position detected by the second position sensor 612 based on the time measured by the timer T, and switches the switching valve 35 toward the position detected by the first position sensor 611. Specifically, the control unit 34 determines the switching timing of the switching valve 35 to one position sensor (e.g., first position sensor 611) based on the time measured by timer T from the point in time when movement begins from the detection position of one position sensor (e.g., first position sensor 611) to the detection position of the other position sensor (e.g., second position sensor 612), and determines the switching timing of the switching valve 35 to the other position sensor (e.g., second position sensor 612) based on the detection by one position sensor (e.g., first position sensor 611).

[0066] Furthermore, when ready-mixed concrete C is supplied to the concrete pumping pipe 22, if both position sensors 611 and 612 detect the switching valve 35, the control unit 34 determines that both position sensors 611 and 612 are malfunctioning and transmits an alert signal to the operation unit 5.

[0067] At this time, when an operator or the like recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode and switches the switching valve 35 from one concrete cylinder 31A to the other concrete cylinder 31B, and from the other concrete cylinder 31B to one concrete cylinder 31A, based on the time measured by the timer T from the timing of the switching valve 35's position change.

[0068] Furthermore, when supplying ready-mix concrete C to the concrete pumping pipe 22, if one position sensor (e.g., first position sensor) 611 continues to detect the switching valve 35 for a predetermined time or longer (e.g., for longer than the time it takes for the switching valve 35 to make one round trip between the first position P1 and the second position P2), and during that time the other position sensor (e.g., second position sensor) 612 does not detect the switching valve 35, the control unit 34 determines that the switching valve 35 is faulty and stops the pump body 30 without switching modes.

[0069] Furthermore, when supplying ready-mix concrete C to the concrete pumping pipe 22, if no signal is received from the hydraulic sensor 62, or if the hydraulic pressure detected by the hydraulic sensor 62 does not fluctuate, the control unit 34 determines that the hydraulic sensor 62 is malfunctioning and transmits a notification signal to the operation unit 5.

[0070] At this time, when the operator or other person recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode, increases the rotational speed of the engine E to a predetermined rotational speed that has been stored in advance, and maintains the rotational speed after the increase.

[0071] Furthermore, when supplying ready-mix concrete C to the concrete pumping pipe 22, if the drive head 332 is moving in one direction within the drive cylinder 32, and the slow detection unit 642 does not detect the drive head 332, but the end detection unit 641 does, the control unit 34 determines that the slow detection unit 642 is malfunctioning and transmits a notification signal to the operation unit 5.

[0072] At this time, when an operator or the like recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode and switches the direction of movement of the drive head 332 at the timing of detection of the drive head 332 by the end detection unit 641 (i.e., when the drive head 332 reaches the one-sided switching position P4) without reducing the movement speed of the drive head 332.

[0073] Alternatively, the control unit 34 switches the direction of movement of the drive head 332 at the timing of detection of the drive head 332 by the head-side end sensor 63 (i.e., when the drive head 332 reaches the other-side switching position P3), and after decelerating the movement speed of the drive head 332 moving toward one side based on the time measured by the timer T from the timing of this direction of movement switching, it switches the direction of movement of the drive head 332 at the timing of detection of the drive head 332 by the end detection unit 641.

[0074] Furthermore, when supplying ready-mix concrete C to the concrete pumping pipe 22, if the drive head 332 is moving towards one side within the drive cylinder 32, the timer T measures the timing from when the drive head 332 begins to move towards one side from the other-side switching position P3. If the end detection unit 641 does not detect the drive head 332 after a predetermined time has elapsed, the control unit 34 determines that the end detection unit 641 is malfunctioning and transmits a notification signal to the operation unit 5.

[0075] At this time, when an operator or the like recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode, and switches the direction of movement of the drive head 332 at the timing when the slow detection unit 642 detects the drive head 332, or at the timing when a predetermined time has elapsed as measured by the timer T from the timing when the slow detection unit 642 detects the drive head 332.

[0076] Furthermore, when supplying ready-mix concrete C to the concrete pumping pipe 22, if the drive head 332 is moving towards one side within the drive cylinder 32, and a predetermined time has elapsed based on the time measured by timer T from the moment the drive head 332 began moving towards one side from the other-side switching position P3, the control unit 34 determines that both the slow detection unit 642 and the end detection unit 641 are malfunctioning and transmits a notification signal to the operation unit 5.

[0077] At this time, if the operator or other person recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode, decelerates the drive head 332 based on the time measured by the timer T from the moment the drive head 332 begins to move from the other side switching position P3 toward one side, and then switches the direction of movement after a predetermined time has elapsed since the deceleration. Alternatively, the control unit 34 switches the direction of movement of the drive head 332 based on the time measured by the timer T from the moment the drive head 332 begins to move from the other side switching position P3 toward one side.

[0078] Furthermore, when supplying ready-mix concrete C to the concrete pumping pipe 22, if the rotational speed instruction (instruction value of the rotational speed instruction signal) from the control unit 34 to the engine E does not match the rotational speed of the engine E detected by the rotational speed sensor 65, the control unit 34 determines that the rotational speed sensor 65 is malfunctioning and transmits a notification signal to the operation unit 5.

[0079] At this time, when the operator or other person recognizes the notification from the notification unit 50 and operates the emergency mode switch S2, the control unit 34 switches the mode from normal mode to emergency mode and controls the rotation speed of the engine E by rotation speed instruction (rotation speed instruction signal) without using the detection signal (detected rotation speed) from the rotation speed sensor 65.

[0080] The concrete pump truck 1 described above comprises a pump body (piston-type concrete pump) 30 that supplies ready-mix concrete C to a tip opening (discharge section), a detection unit 6 that detects the operation of the pump body 30, and an emergency mode switch S2. The pump body 30 has a concrete cylinder 31 having a one-end opening (discharge port end) 311 from which the contained ready-mix concrete C can be discharged, a piston 33 that discharges the ready-mix concrete C contained in the concrete cylinder 31 from the one-end opening 311, a drive cylinder 32 for driving the piston 33, and a control unit 34 that controls the pump body 30. The emergency mode switch S2 is a switch for operating the control unit 34 in emergency mode.

[0081] With this configuration, when a malfunction (such as an operational abnormality) is detected by the detection unit 6 during the supply of ready-mixed concrete C, the operator can press the emergency mode switch S2 to switch the pump body 30 to emergency mode, thereby continuing the supply of ready-mixed concrete C. In other words, with this concrete pump truck 1, when a malfunction occurs, the operator can be aware of the malfunction and continue using the pump (in this embodiment, the concrete pouring operation).

[0082] Furthermore, the concrete pump truck 1 of this embodiment is equipped with a timer T. The pump body (piston-type concrete pump) 30 has a pair of concrete cylinders 31, a piston 33, and a drive cylinder 32, and also has a switching valve 35 that switches the concrete cylinder 31 connected to the tip opening (discharge section) of the concrete pumping pipe 22 by switching the connection position. The detection unit 6 (specifically, the first position sensor 611 and the second position sensor 612) can detect whether the switching valve 35 is located at each connection position with the pair of concrete cylinders 31. The control unit 34, when a malfunction of the detection unit 6 (specifically, the first position sensor 611 or the second position sensor 612) is detected based on the detection of the detection unit 6 and the emergency mode switch S2 is operated to enter emergency mode, determines the switching timing of the concrete cylinder 31 connected to the tip opening of the switching valve 35 based on the timer T.

[0083] With this configuration, by switching to emergency mode, the switching operation (switching timing) of the switching valve 35 is controlled based on the time measured by the timer T. Therefore, even if the detection unit 6, which can detect the position of the switching valve 35 at each connection position, malfunctions, the supply of ready-mixed concrete C can be continued.

[0084] Furthermore, in the concrete pump truck 1 of this embodiment, the control unit 34 stops the pump body (piston-type concrete pump) 30 when a malfunction of the switching valve 35 is detected based on the detection of the detection unit 6 (specifically, the first position sensor 611 and the second position sensor 612). This ensures that the pump body 30 is reliably stopped when the switching valve 35 malfunctions. In other words, when the switching valve 35 in the pump body 30 malfunctions, it becomes impossible to supply ready-mix concrete to the concrete pumping pipe 22, so the control unit 34 stops the pump body 30 when it determines that the switching valve 35 has malfunctioned.

[0085] Furthermore, the concrete pump truck 1 of this embodiment includes an engine (drive source) E and a hydraulic pump 362 driven by the engine E. The drive cylinder 32 is a hydraulic cylinder connected to the hydraulic pump 362, and the detection unit 6 (specifically, the hydraulic sensor 62) is capable of detecting the hydraulic pressure of the drive cylinder 32. When the emergency mode switch S2 is operated and the system enters emergency mode based on the detection of the detection unit 6, the control unit 34 sets the rotational speed of the engine E to a predetermined rotational speed.

[0086] With this configuration, by switching to emergency mode, the rotational speed of the engine E is controlled without relying on the detection of hydraulic pressure in the drive cylinder (hydraulic cylinder) 32. Therefore, even if the detection unit 6 capable of detecting the hydraulic pressure in the drive cylinder 32 fails, the supply of ready-mixed concrete C can continue.

[0087] Furthermore, in the concrete pump truck 1 of this embodiment, the piston 33 includes a discharge head 331 that can move towards one end opening (discharge port end) 311 and away from the one end opening 311 within the concrete cylinder 31, and a drive head 33 that can move to one side within the drive cylinder 32 to move the discharge head 331 to one side and to the other side within the drive cylinder 32 to move the discharge head 331 to the other side. The detection unit 6 includes an end detection unit (first detection unit) 641 that detects that the drive head 332 is located at a one-side switching position P4 where it switches from moving to one side to moving to the other side, and a slow detection unit (second detection unit) 642 that detects the drive head 332 located at a deceleration position P5 which is on one side of the center of the movement stroke from the other-side switching position P3 where it switches from moving to the other side to moving to one side to the one-side switching position P4, and on the other side of the one-side switching position P4. Furthermore, when the drive head 332 moves to one side, the control unit 34 reduces the movement speed of the drive head 332 when the slow detection unit 642 detects the drive head 332, and switches the direction of movement of the drive head 332 from one side to the other when the end detection unit 641 detects the drive head 332. However, when the emergency mode switch S2 is operated and the system enters emergency mode due to a failure of the slow detection unit 642 being detected based on the detections of the end detection unit 641 and the slow detection unit 642, the control unit 34 does not perform any control over the movement of the drive head 332 based on the detections of the slow detection unit 642.

[0088] With this configuration, when the system is switched to emergency mode, the drive head 332 does not decelerate based on the detection of the slow detection unit 642 when moving to one side, and the direction of movement of the drive head 332 is switched based on the detection of the end detection unit 641. Therefore, even if the slow detection unit 642 fails, the supply of ready-mixed concrete C can be continued.

[0089] Furthermore, the concrete pump truck 1 of this embodiment is equipped with a timer T. The piston 33 has a discharge head 331 that can move towards one end opening (discharge port end) 311 and away from one end opening 311 within the concrete cylinder 31, and a drive head 332 that can move to one side within the drive cylinder 32 to move the discharge head 331 to one side, and a drive head 332 that can move to the other side within the drive cylinder 32 to move the discharge head 331 to the other side. The detection unit 6 has an end detection unit (first detection unit) 641 that detects that the drive head 332 is at a one-side switching position P4 where it switches from moving to one side to moving to the other side, and a movement stop of the drive head 332 from the other-side switching position P3 where it switches from moving to the other side to moving to one side to the one-side switching position P4. The control unit 34 has a slow detection unit (second detection unit) 642 that detects a drive head 332 located at a deceleration position P5 that is on one side of the center position of the lock and on the other side of the one-side switching position P4. When the drive head 332 moves to one side, the control unit 34 decelerates the movement speed of the drive head 332 when the slow detection unit 642 detects the drive head 332, and switches the direction of movement of the drive head 332 from one side to the other when the end detection unit 641 detects the drive head 332. On the other hand, when a malfunction of the end detection unit 641 is detected based on the time measured by the timer T and the detection by the end detection unit 641, and the emergency mode switch S2 is operated and the system enters emergency mode, the control unit 34 switches the direction of movement of the drive head 332 from one side to the other based on the detection by the slow detection unit 642.

[0090] With this configuration, when the system is switched to emergency mode, the direction of movement of the drive head 332 is switched based on the detection by the slow detection unit 642 when the drive head 332 moves to one side. Therefore, even if the end detection unit 641 fails, the supply of ready-mixed concrete C can be continued.

[0091] Furthermore, in the concrete pump truck 1, when emergency mode is activated, the control unit 34 may determine, based on the time measured by the timer T, the timing at which the slow detection unit (second detection unit) 642 detects the drive head 332 during its movement to one side and then switches the direction of movement from one side to the other.

[0092] With this configuration, when the system is switched to emergency mode, the direction of movement of the drive head 332 is switched based on the time measured by the timer T triggered by the detection of the drive head 332 by the slow detection unit 642 (i.e., after a predetermined time has elapsed) when the drive head 332 moves to one side. This suppresses a decrease in the stroke length of the drive head 332, and thereby suppresses a decrease in the amount of ready-mixed concrete C supplied to the tip opening (discharge section) of the concrete pumping pipe 22 (more specifically, the amount supplied per unit time) when the system is switched to emergency mode.

[0093] Furthermore, the concrete pump is equipped with a timer T. The piston 33 has a discharge head 331 that can move towards one end opening (discharge port end) 311 and away from one end opening 311 within the concrete cylinder 31, and a drive head 332 that can move to one side within the drive cylinder 32 to move the discharge head 331 to one side, and to the other side within the drive cylinder 32 to move the discharge head 331 to the other side. The detection unit 6 has an end detection unit (first detection unit) 641 that detects that the drive head 332 is at a one-side switching position P4 where it switches from moving to one side to moving to the other side, and a position on one side of the center of the movement stroke of the drive head 332 from the other-side switching position P3 where it switches from moving to the other side to moving to one side to the one-side switching position P4, and on the other side of the one-side switching position P4. The control unit 34 has a slow detection unit (second detection unit) 642 that detects the drive head 332 located at the deceleration position P5 on the side, and when the drive head 332 moves to one side, the control unit 34 decelerates the movement speed of the drive head 332 when the slow detection unit 642 detects the drive head 332, and when the end detection unit 641 detects the drive head 332, it switches the direction of movement of the drive head 332 from one side to the other side. On the other hand, when a failure of the end detection unit 641 and the slow detection unit 642 is detected based on the time measured by the timer T, the detection by the end detection unit 641, and the detection by the slow detection unit 642, the emergency mode switch S2 is operated and the system enters emergency mode, and the timing at which the direction of movement of the drive head 332 is switched from the other side to one side is determined based on the time measured by the timer T.

[0094] With this configuration, when the system is switched to emergency mode, the movement of the drive head 332 to one side is switched from one direction to the other based on the elapsed time since the movement direction was switched from the other side to the one side. Therefore, even if both the end detection unit 641 and the slow detection unit 642 fail, the supply of ready-mixed concrete C can be continued.

[0095] Furthermore, the concrete pump truck 1 of this embodiment is equipped with an engine (drive source) E, which is the drive source for the pump body (piston-type concrete pump) 30. The detection unit 6 (more specifically, the rotation speed sensor 65) is capable of detecting the rotation speed of the engine E, and the control unit 34 controls the rotation speed of the engine E so that the rotation speed instruction (instruction value of the rotation speed instruction signal) from the control unit 34 to the engine E matches the rotation speed detected by the detection unit 6. However, when a malfunction of the detection unit 6 is detected based on the detection of the detection unit 6, and the emergency mode switch is operated to enter emergency mode, the rotation speed of the engine E is controlled by the rotation speed instruction without being based on the detection of the detection unit 6.

[0096] With this configuration, by switching to emergency mode, the rotational speed of the engine E is controlled based on a rotational speed instruction output from the control unit 34, rather than on the actual rotational speed of the engine E detected by the detection unit 6 (i.e., not on feedback control). Therefore, even if the detection unit 6, which is capable of detecting the rotational speed of the engine E, fails, the supply of ready-mixed concrete C can continue.

[0097] Furthermore, the concrete pump truck 1 of this embodiment is equipped with a notification unit 50. The control unit 34 notifies the notification unit 50 when a malfunction is detected based on the detection unit 6. This allows operators and others to more easily and reliably understand the occurrence of a malfunction through notifications from the notification unit 50, and as a result, they can more reliably switch to emergency mode when a malfunction occurs.

[0098] It should be noted that the concrete pump of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, and a part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, a part of the configuration of one embodiment can be deleted.

[0099] The concrete pump 3 in the above embodiment is mounted on a vehicle and constitutes part of the concrete pump truck 1, but the configuration is not limited to this. In addition to being mounted on a vehicle, the concrete pump 3 may also be used in stationary concrete pump devices or fixed concrete pump devices.

[0100] Furthermore, in the concrete pump 3 of the above embodiment, the emergency mode switch S2 is located on a remote control type control unit 5 that is operated while being held (carried) by the operator, but the configuration is not limited to this. The emergency mode switch S2 may be located on a control panel located near the pump body 30 in the vehicle, or inside the vehicle's cabin, etc.

[0101] Furthermore, the emergency mode switch S2 is not limited to a physical switch, but may also be a switch displayed on a touch panel or the like (switch indicator).

[0102] Furthermore, in the concrete pump 3 of the above embodiment, the control unit 34 stops the concrete pump 3 when a malfunction is detected, but the configuration is not limited to this. The control unit 34 may be configured to continue operating the concrete pump 3 at a slow speed when a malfunction is detected. In this case, when the emergency mode switch S2 is operated (pressed, etc.), the control unit 34 may switch the mode to emergency mode and increase the operating speed of the concrete pump 3 to the operating speed before the operation of the emergency mode switch S2.

[0103] Furthermore, in the above embodiment, when the emergency mode switch S2 is operated (pressed, etc.), the concrete pump 3 switches to emergency mode and immediately restarts the operation that was in place before the operation of the emergency mode switch S2 (rotates the concrete pump 3 forward), but the configuration is not limited to this. The concrete pump 3 may be configured to wait for the operation (pressed, etc.) of the start switch after the mode switch is switched when the emergency mode switch S2 is operated, and to start after the start switch is operated.

[0104] Furthermore, in the concrete pump 3 of the above embodiment, the drive source for the hydraulic pump 362 that adjusts the hydraulic pressure in the drive cylinder (hydraulic cylinder) 32 is the engine E, but the configuration is not limited to this. The drive source for the hydraulic pump 362 may be a motor or the like.

[0105] Furthermore, in the notification unit 50 of the above embodiment, the operator is notified of a malfunction in the detection unit 6 by sounding the buzzer 50a and lighting the lamp 50b, but the system is not limited to this configuration. The notification unit 50 may consist of either the buzzer 50a or the lamp 50b. The notification unit 50 may also consist of an audio output unit or the like. In other words, the notification unit 50 only needs to be configured so that the notification can be perceived by the operator through sight, hearing, or touch.

[0106] Furthermore, while the control unit 34 in the above embodiment immediately stops the concrete pump 3 when it detects (determines) a predetermined malfunction in the concrete pump 3, the configuration is not limited to this. The control unit 34 may also decelerate the concrete pump 3 and then gradually stop it when it detects (determines) a predetermined malfunction in the concrete pump 3. Alternatively, the control unit 34 may announce that the concrete pump 3 is about to stop via the notification unit 50 before stopping the concrete pump 3.

[0107] Furthermore, although the concrete pump 3 of the above embodiment has a timer T built into the control unit 34, the configuration is not limited to this. The control unit 34 may also be configured to utilize a timer T located in a component other than the control unit 34.

[0108] Furthermore, in the above embodiment, the control unit 34 determined that a malfunction occurred when the measurement time by the timer T exceeded a predetermined time (a fixed time set in advance), but the configuration is not limited to this. The predetermined time may be changed each time depending on the operating speed of the drive cylinder 32 (piston 33) and the switching valve 35.

[0109] Furthermore, in the above embodiment, the control unit 34 determines that both position sensors 611 and 612 are faulty when both position sensors 611 and 612 detect the switching valve 35, and performs the switching operation of the switching valve 35 based on the time measured by the timer T, but the configuration is not limited to this. If the control unit 34 can identify which of the position sensors 611 and 612 is faulty from other information, it may use the timer T when switching using the faulty position sensor 611 or 612 (the other switching of the switching valve 35 is performed using the non-faulty position sensor 612 or 611).

[0110] Furthermore, in the above embodiment, the control unit 34 drives the drive source at a predetermined rotational speed (a predetermined constant rotational speed) that has been stored in advance when the hydraulic sensor 62 fails, but the configuration is not limited to this. The predetermined rotational speed may be specified by the operator or the like when switching modes. [Explanation of symbols]

[0111] 1...Concrete pump truck, 2...Boom device, 20...Boom, 22...Concrete pumping piping, 21a, 21b, 21c, 21d...Beam, 3...Concrete pump, 30...Pump body (piston-type concrete pump), 31...Concrete cylinder, 31A...One concrete cylinder, 31B...The other concrete cylinder, 311...One end opening (discharge end), 312...The other end opening, 32...Drive cylinder, 321...Hydraulic oil inlet / outlet, 33... Piston, 331…Discharge head, 332…Drive head, 333…Rod, 34…Control unit, 35…Switching valve, 35a…Cylinder side engagement part, 36…Hydraulic system, 361…Oil tank, 362…Hydraulic pump, 363…Valve unit, 364…Hydraulic piping, 365…Pilot check valve, 4…Hopper, 5…Operation unit, 50…Notification unit, 50a…Buzzer, 50b…Lamp, 51…Main power switch, 52…Pump start switch, 53a…Rotation speed switch, 54a…Discharge unit Control switch, 55a... Right swivel switch, 55b... Left swivel switch, 56a, 56b, 56c, 56d, 56e, 56f, 56g, 56h... Beam luffing switch, 57a... Boom speed control switch, 6... Detection unit, 61... Position sensor, 611... First position sensor, 612... Second position sensor, 62... Hydraulic sensor, 63... Head-side end sensor, 64... Rod-side end sensor, 641... End detection unit (first detection unit), 642... Slow detection unit (second Detection unit), 65... Rotation speed sensor, 100... Concrete pump, 101... Drive cylinder, 102... Conveyor cylinder, 103... Piston, 104... Conveyor piston, 105... Piston rod, 106... Cylinder switching sensor, C... Ready-mix concrete, E... Engine (drive source), F... Vehicle frame, P1... First position, P2... Second position, P3... Other side switching position, P4... One side switching position, P5... Deceleration position, S1... Emergency stop switch, S2... Emergency mode switch, T... Timer

Claims

1. A piston-type concrete pump that supplies ready-mix concrete to the discharge section, A detection unit that detects the operation of the piston-type concrete pump, Equipped with an emergency mode switch, The aforementioned piston-type concrete pump is A concrete cylinder having a discharge port end capable of discharging the contained ready-mixed concrete, A piston that discharges the ready-mixed concrete contained in the concrete cylinder from the discharge port end, A drive cylinder for driving the piston, It includes a control unit for controlling the piston-type concrete pump, The emergency mode switch is a switch for operating the control unit in emergency mode, in the concrete pump.

2. Equipped with a timer, The piston-type concrete pump has a pair of concrete cylinders, a pair of pistons, and a pair of drive cylinders, and also has a switching valve that switches the concrete cylinder connected to the discharge section by switching the connection position. The detection unit is capable of detecting whether the switching valve is located at each connection position with the pair of concrete cylinders. The concrete pump according to claim 1, wherein the control unit determines the switching timing of the concrete cylinder connected to the discharge section of the switching valve based on the timer when the emergency mode switch is operated due to a malfunction of the detection unit detected based on the detection unit's detection, thereby entering the emergency mode.

3. The concrete pump according to claim 2, wherein the control unit stops the piston-type concrete pump when a malfunction of the switching valve is detected based on the detection of the detection unit.

4. Power source and The system comprises a hydraulic pump driven by the aforementioned power source, The aforementioned drive cylinder is a hydraulic cylinder connected to the hydraulic pump, The detection unit is capable of detecting the hydraulic pressure of the hydraulic cylinder, The concrete pump according to claim 1, wherein the control unit sets the rotation speed of the drive source to a predetermined rotation speed when the emergency mode switch is operated and the emergency mode is activated based on the detection of the detection unit, thereby detecting a malfunction of the detection unit.

5. The aforementioned piston is Within the concrete cylinder, a discharge head is provided which is capable of moving toward one side toward the discharge port end and moving toward the other side toward the discharge port end, The drive cylinder includes a drive head that is capable of moving the discharge head to one side within the drive cylinder, and moving the discharge head to the other side within the drive cylinder, The detection unit, A first detection unit detects that the drive head is in a one-side switching position where it switches from moving to one side to moving to the other side, The drive head has a second detection unit that detects the drive head at a deceleration position that is on one side of the center of the movement stroke from the other-side switching position, where the drive head switches from movement to the other side to movement to the one-side switching position, and on the other side of the one-side switching position. The control unit, When the drive head moves to one side, the second detection unit reduces the speed of the drive head when it detects the drive head, and the first detection unit switches the direction of movement of the drive head from one side to the other when it detects the drive head, The concrete pump according to claim 1, wherein when the emergency mode switch is operated and the emergency mode is activated due to a malfunction of the second detection unit detected based on the detections of the first detection unit and the second detection unit, control of the movement of the drive head based on the detection of the second detection unit is not performed.

6. Equipped with a timer, The aforementioned piston is Within the concrete cylinder, a discharge head is provided which is capable of moving toward one side toward the discharge port end and moving toward the other side toward the discharge port end, The drive cylinder includes a drive head that is capable of moving the discharge head to one side within the drive cylinder, and moving the discharge head to the other side within the drive cylinder, The detection unit, A first detection unit detects that the drive head is in a one-side switching position where it switches from moving to one side to moving to the other side, The drive head has a second detection unit that detects the drive head at a deceleration position that is on one side of the center of the movement stroke from the other-side switching position, where the drive head switches from movement to the other side to movement to the one-side switching position, and on the other side of the one-side switching position. The control unit, When the drive head moves to one side, the second detection unit reduces the speed of the drive head when it detects the drive head, and the first detection unit switches the direction of movement of the drive head from one side to the other when it detects the drive head, The concrete pump according to claim 1, wherein when a malfunction of the first detection unit is detected based on the time measured by the timer and the detection of the first detection unit, the emergency mode switch is operated and the emergency mode is activated, and the direction of movement of the drive head is switched from one side to the other side based on the detection of the second detection unit.

7. The concrete pump according to claim 6, wherein, when the emergency mode is activated, the control unit determines, based on the timer, the timing at which the second detection unit detects the drive head during its movement to one side and then switches the direction of movement from one side to the other.

8. Equipped with a timer, The aforementioned piston is Within the concrete cylinder, a discharge head is provided which is capable of moving toward one side toward the discharge port end and moving toward the other side toward the discharge port end, The drive cylinder includes a drive head that is capable of moving the discharge head to one side within the drive cylinder, and moving the discharge head to the other side within the drive cylinder, The detection unit, A first detection unit detects that the drive head is in a one-side switching position where it switches from moving to one side to moving to the other side, The drive head has a second detection unit that detects the drive head at a deceleration position that is on one side of the center of the movement stroke from the other-side switching position, where the drive head switches from movement to the other side to movement to the one-side switching position, and on the other side of the one-side switching position. The control unit, When the drive head moves to one side, the second detection unit reduces the speed of the drive head when it detects the drive head, and the first detection unit switches the direction of movement of the drive head from one side to the other when it detects the drive head, The concrete pump according to claim 1, wherein when a malfunction of the first detection unit and the second detection unit is detected based on the measurement time of the timer, the detection of the first detection unit, and the detection of the second detection unit, the emergency mode switch is operated and the emergency mode is activated, and the timing at which the direction of movement of the drive head is switched from one side to the other is determined based on the timer, from the moment the direction of movement of the drive head is switched from the other side to the one side.

9. The piston-type concrete pump is equipped with a drive source, The detection unit is capable of detecting the rotational speed of the drive source, The control unit, The rotational speed of the drive source is controlled so that the rotational speed instruction from the control unit to the drive source matches the rotational speed detected by the detection unit, The concrete pump according to claim 1, wherein when a malfunction of the detection unit is detected based on the detection unit's detection, the emergency mode switch is operated and the emergency mode is activated, and the rotation speed of the drive source is controlled by the rotation speed instruction without being based on the detection unit's detection.

10. Equipped with a news department, The concrete pump according to any one of claims 1 to 9, wherein the control unit causes the notification unit to notify when a malfunction is detected based on the detection unit's detection.

Images