Suction vehicle

Abstract

To provide a suction vehicle having a simple configuration, which nevertheless allows easy locking and unlocking of a tailgate.SOLUTION: A suction vehicle 2 comprises a tank body 6 having a rear opening, a tailgate 7 capable of opening and closing the rear opening, an opening / closing cylinder 9 for opening and closing the tailgate 7, a lock cylinder 71 for mechanically restricting an opening operation of the tailgate 7, a sequence circuit S for controlling operations of the opening / closing cylinder 9 and the lock cylinder 71, a control lever 27 for giving an operation instruction for the opening / closing cylinder 9 to the sequence circuit S, and a lock detection unit for detecting at least one of a lock closed state in which the opening operation of the tailgate 7 is restricted and a lock open state in which the opening operation of the tailgate 7 is not restricted, wherein the sequence circuit S causes the lock cylinder 71 to perform an opening operation based on a detection state of the lock detection unit when the control lever 27 is operated.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a suction vehicle. [Background technology]

[0002] Conventionally, suction vehicles have been known that suck up wastewater and sludge from sewers and gutters and collect them in a tank. For example, as disclosed in Patent Document 1, this type of suction vehicle includes a hollow tank body, a tailgate that can open and close a rear opening of the tank body, and a gate lock mechanism that can fasten the tailgate to the opening edge of the rear opening.

[0003] In such a suction vehicle, an opening / closing cylinder (e.g., a hydraulic cylinder) is connected to the tailgate, and the rear opening can be opened and closed by operating the opening / closing cylinder. The gate lock mechanism of the tailgate can be switched between a closed state in which the tailgate is locked to the rear opening, and an open state in which the tailgate is unlocked to the rear opening, by operating the lock cylinder (e.g., a hydraulic cylinder). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-67451 Summary of the Invention [Problem to be solved by the invention]

[0005] In a suction vehicle equipped with the above-mentioned tailgate lock mechanism, the tailgate opening / closing cylinder and the lock cylinder are operated by separate operating systems, each controlled by a manual control valve. To prevent damage to the gate lock mechanism, as a safety measure, hydraulic pressure to the tailgate opening / closing cylinder is cut off when the gate lock mechanism is in the closed position. In addition, the operator must confirm visually or by means of an alarm that the gate lock mechanism is in the open position before opening or closing the tailgate.

[0006] However, it was necessary to switch between opening and closing the tailgate and the gate lock mechanism as needed, and it was also time-consuming to check whether the gate lock mechanism was open or closed. Furthermore, when closing the tailgate, it was necessary to first switch the gate lock mechanism to the open position, then close the tailgate, and then switch the gate lock mechanism to the closed position, meaning that the gate lock mechanism had to be switched twice. In this case, the opening operation was performed each time, assuming the possibility that the gate lock mechanism had not been visually confirmed to be in the open position, so two switches were required even if the gate lock mechanism was in the open position.

[0007] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a suction vehicle that can easily open and close the tailgate while preventing damage to the tailgate's gate lock mechanism. [Means for solving the problem]

[0008] The present invention provides a means for solving the above-described problems as follows: That is, the present invention provides a suction vehicle including a tank body having a rear opening and a tailgate capable of opening and closing the rear opening, the vehicle comprising: a tailgate opening / closing unit that opens and closes the tailgate, a locking unit that mechanically restricts the opening of the tailgate from a closed state, a control unit that controls the operation of the tailgate opening / closing unit and the locking unit, a tailgate operating unit that gives an operation instruction for the tailgate opening / closing unit to the control unit, and a lock detection unit that detects at least one of a locked-closed state in which the opening of the tailgate is restricted by the locking unit and a locked-open state in which the opening of the tailgate is not restricted by the locking unit, and the control unit causes the locking unit to perform an unlocking operation based on the detection state of the lock detection unit when the tailgate operating unit is operated.

[0009] According to the above configuration, the tailgate can be easily opened and closed while preventing damage to the gate lock mechanism of the tailgate. Specifically, when the operating lever is operated, if the lock detection unit does not detect the unlocked state of the lock unit (when the lock unit is in the locked closed state or when the lock unit is in a half-open state between the locked closed state and the unlocked state), the control unit automatically opens the lock unit, thereby preventing damage to the gate lock mechanism. Furthermore, after the lock detection unit detects the unlocked state of the lock unit, the tailgate can be opened or closed directly. This eliminates the need to switch between operating the gate lock mechanism and operating the tailgate, and allows the tailgate to be opened or closed with a single operation.

[0010] In the suction vehicle having the above configuration, it is preferable that the control unit inhibits the operation of the tailgate opening / closing unit based on the detection state of the lock detection unit. In this case, if the tailgate operation unit is being operated when the lock detection unit detects the unlocked state of the lock unit, it is preferable that the control unit releases the inhibition of the operation of the tailgate opening / closing unit and opens or closes the tailgate.

[0011] According to the above configuration, once the lock detection unit detects that the lock unit is in the unlocked state, the operation proceeds directly to opening and closing the tailgate, eliminating the need to switch between operating the gate lock mechanism and operating the tailgate, and allowing the tailgate to be opened and closed with a single operation.

[0012] In the suction vehicle having the above configuration, it is preferable that a notification is given based on the detection state of the lock detection unit.

[0013] According to the above configuration, it is possible to prevent the tailgate from being opened accidentally during the opening operation of the locking portion.

[0014] In a suction vehicle of the above configuration, it is preferable that the tank body is provided with a hatch guard extending to the side and / or downward of the vehicle around the periphery of the rear opening, and that the lock detection unit is positioned near the hatch guard and further forward of the hatch guard.

[0015] According to the above configuration, it is possible to prevent the lock detection section from becoming soiled by sludge or the like that has overflowed from the tank body, making it impossible to detect the open / closed state of the lock section.

[0016] In a suction vehicle having the above configuration, one of the tailgate and the tank body is provided with an engagement portion with which the locking portion engages when the lock is in the closed state and the tailgate is closed, and the other of the tailgate and the tank body is provided with an opening through which the engagement portion is inserted when the tailgate is closed, and the opening is preferably covered with a cover formed of a flexible material and having an insertion portion that can be pushed out, and when the engagement portion is inserted into the opening, the engagement portion pushes out the insertion portion formed in the cover.

[0017] According to the above configuration, when the engagement portion is not inserted, the insertion portion is closed, preventing sludge and other materials that have overflowed from the tank body from scattering in unintended directions, such as in front of the tank body or behind the tailgate, and when the engagement portion is inserted, the insertion portion is pushed open, allowing for easy engagement.

[0018] In the suction vehicle having the above configuration, it is preferable that the suction vehicle has a tailgate closed detection unit that is electrically connected to the control unit and detects the closed state of the tailgate, and that the control unit performs a lock-close operation of the lock unit when the tailgate closed detection unit detects the closed state of the tailgate and the tailgate operating unit is being operated to close.

[0019] According to the above configuration, when the tailgate is closed, by continuing to perform the closing operation of the tailgate even after the closed state of the tailgate is detected, the lock unit is closed and the gate lock mechanism can be switched to the locked state, and the gate lock mechanism can be switched to the locked state by the tailgate operating unit. This eliminates the need to switch between the closing operation of the tailgate and the closing operation of the gate lock mechanism, and allows the gate lock mechanism to be switched to the locked state with a single operation. [Effects of the Invention]

[0020] According to the suction vehicle of the present invention, the tailgate can be easily opened and closed while preventing damage to the gate lock mechanism of the tailgate. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a left side view showing a schematic configuration of a suction vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a rear view of the suction vehicle of FIG. 1. [Figure 3] FIG. 2 is a front view showing a gate lock mechanism of the tailgate. [Figure 4] FIG. 4 is a side cross-sectional view showing an unlocked state of the gate lock mechanism of the tailgate. [Figure 5] FIG. 4 is a side cross-sectional view showing a locked state of the gate lock mechanism of the tailgate. [Figure 6] FIG. 5 is a view taken along the line X1-X1 in FIG. 4. [Figure 7] FIG. 2 is a schematic diagram showing a hydraulic circuit of the suction vehicle of FIG. 1. [Figure 8] 2 is a schematic diagram showing a part of a sequence circuit of the suction vehicle of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0023] FIG. 1 is a left side view showing a schematic configuration of a suction vehicle 2 according to an embodiment of the present invention, and FIG. 2 is a rear view showing the suction vehicle 2. As shown in FIG.

[0024] As shown in Figures 1 and 2, in the suction vehicle 2, a subframe 4 is mounted on the vehicle chassis frame 3, with the suction device 1 mounted at the front and a receiver tank 5 for collecting materials to be collected mounted at the rear. Materials to be collected include sludge, earth and sand, waste liquid, etc. In the following explanation, the front-to-rear direction refers to the same direction as the front-to-rear direction of the suction vehicle 2 (the direction along the traveling direction), and the left-to-right direction refers to the left-to-right direction when the suction vehicle 2 is facing forward.

[0025] The receiver tank 5 includes a tank body 6 having a rear opening, and a tailgate 7 that opens and closes the rear opening. The tailgate 7 is rotatably supported via a hinge pin 8 at the upper rear end of the tank body 6. Furthermore, an opening / closing cylinder 9 is disposed between the tank body 6 and the tailgate 7. The tailgate 7 opens and closes the rear opening of the tank body 6 by extending and retracting the opening / closing cylinder 9. That is, the front end of the opening / closing cylinder 9 is rotatably supported on a side of the tank body 6, while the rear end (the tip of the cylinder rod) of the opening / closing cylinder 9 is rotatably supported on a side of the tailgate 7. When the opening / closing cylinder 9 is retracted, the tailgate 7 closes the rear opening of the tank body 6, while when the opening / closing cylinder 9 is extended, the tailgate 7 rotates about the hinge pin 8 to open the rear opening of the tank body 6.

[0026] When the tailgate 7 is in a closed state, closing the rear opening, the tailgate 7 is pressed against the tank-side flange 6a, which is the opening edge of the rear opening. A gasket 73 is interposed between the tank-side flange 6a and the gate-side flange 7a of the tailgate 7, ensuring that the tailgate 7 securely closes the rear opening of the tank body 6 and prevents the collected materials from leaking out. A hatch guard 81 is provided around the periphery of the tank-side flange 6a to cover the periphery of the tailgate 7 when the tailgate 7 is closed and to prevent scattering and guide the collected materials when they are discharged. The hatch guard 81 is composed of, for example, a guard main body 81a, which is an arch-shaped steel plate that covers the periphery of the tank, and a side plate 81c that extends rearward from the outer edge of the guard main body 81a. The guard main body 81a is welded to the periphery of the tank-side flange 6a, covering the sides and bottom of the tailgate 7 except for the upper side. In addition to preventing scattering and guiding the discharge, the side plate 81c also prevents pinching and other issues when the tailgate 7 is opened or closed. In this embodiment, a pair of left and right gate lock mechanisms 70, 70 are provided for fastening the tailgate 7 to the tank-side flange 6a when the tailgate 7 closes the rear opening. Since the configurations of the gate lock mechanisms 70, 70 are symmetrical, the following description will be given representatively of the gate lock mechanism 70 located on the left side of the vehicle body (the same applies to the opening / closing cylinder 9, the tilting cylinder 15, and the sensors 75 to 77 described later).

[0027] As shown in FIGS. 3 to 6 , the gate lock mechanism 70 includes a lock cylinder 71 and a boss 72 that can engage with a cylinder rod 71a of the lock cylinder 71. One end of the lock cylinder 71 is rotatably supported on a hatch guard 81 provided on the periphery of the tank-side flange 6a of the tank body 6, while the other end of the lock cylinder 71 (the tip of the cylinder rod 71a) is insertable into an engagement hole 72a provided in the boss 72. As the lock cylinder 71 extends or retracts, the tip of the cylinder rod 71a can engage with or disengage from the boss 72. When installing the lock cylinder 71 on the hatch guard 81, the lock cylinder 71 is installed not on the guard body 81a made of steel plate but on a patch 81b welded to the guard body 81a. This allows for increased plate thickness and ensures strength, and also allows the gate lock mechanism 70 to be assembled separately from the tank body 6, improving the efficiency of the manufacturing process.

[0028] When the lock cylinder 71 is extended, the tip of the cylinder rod 71a engages with the boss portion 72, and when the lock cylinder 71 is retracted, the tip of the cylinder rod 71a disengages from the boss portion 72. When the lock cylinder 71 is extended and the tip of the cylinder rod 71a engages with the boss portion 72 (the state shown by the two-dot chain lines in Figures 3 and 4 and the solid line in Figure 5), the gate lock mechanism 70 is switched to a locked state, and the tailgate 7 is fastened to the tank-side flange 6a. When the lock cylinder 71 is retracted and the tip of the cylinder rod 71a disengages from the boss portion 72 (the state shown by the solid lines in Figures 3 and 4 and the two-dot chain line in Figure 5), the gate lock mechanism 70 is switched to an unlocked state, and the tailgate 7 is released from the tank-side flange 6a.

[0029] A hatch guard 81 on the periphery of the tank-side flange 6a of the tank body 6 is provided with a guide member 74 that guides the reciprocating movement of the cylinder rod 71a as the lock cylinder 71 extends and retracts. The guide member 74 contacts the cylinder rod 71a, allowing for position adjustment and preventing bending of the cylinder rod 71a due to shear loads. Specifically, even if the tailgate 7 is not opened while the gate lock mechanism 70 remains locked, an opening force is applied to the tailgate 7 due to the pushing force of cargo in the receiver tank 5 or pressure buildup within the receiver tank 5. If the cylinder rod 71a is bent by this opening force, a gap will form between the tailgate 7 and the tank body 6, even though the lock cylinder 71 is extended, preventing the gate lock mechanism 70 from functioning properly. However, by reducing bending of the cylinder rod 71a with the guide member 74, the locking force of the tailgate 7 to the tank body 6 by the gate lock mechanism 70 can be increased.

[0030] The boss portion 72 is composed of a tank-side boss member 72b attached to the tank body 6 and a gate-side boss member 72c attached to the tailgate 7. When the tailgate 7 closes the rear opening of the tank body 6, the gate-side boss member 72c is inserted into the tank-side boss member 72b, and the two members engage to form the boss portion 72, as shown in FIGS. 3 and 5. At this time, an opening 72e formed in the gate-side boss member 72c is positioned within an opening 72d formed in the tank-side boss member 72b, and the two openings 72d and 72e form an engagement hole 72a into which the tip of the cylinder rod 71a can fit. On the other hand, when the tailgate 7 rotates around the hinge pin 8 and the rear opening of the tank body 6 is opened, the gate-side boss member 72c disengages from the tank-side boss member 72b, as shown in FIG. 4. 6, the portion into which gate-side boss member 72c is inserted (portion indicated by dashed lines) is configured such that slits 78a extending radially from the center are provided in cover 78 formed from a flexible member such as rubber. Also, guide member 79 allows the angle of opening 72e of gate-side boss member 72c to be adjusted so that it continues to face lock cylinder 71, and nut 80 allows the position of opening 72e (position within opening 72d of tank-side boss member 72b) to be adjusted.

[0031] In this way, one of the tailgate 7 and the tank body 6 is provided with an engagement portion (opening 72e in gate-side boss member 72c) with which the cylinder rod 71a of the lock cylinder 71 engages when the lock cylinder 71 is in the locked-closed state and the tailgate 7 is closed, and the other of the tailgate 7 and the tank body 6 is provided with an opening (opening 72d in tank-side boss member 72b) through which this engagement portion is inserted when the tailgate 7 is closed, and this opening is covered with a cover 78, so that when the engagement portion (opening 72e) is inserted into the opening 72d, the engagement portion pushes open an insertion portion (slit 78a) formed in the cover 78 and is inserted therethrough. As a result, when the tailgate 7 is opened to discharge cargo, the insertion portion is closed because the engagement portion is not inserted, and it is possible to prevent sludge and the like that has overflowed from the tank body 6 from passing through the portion where the engagement portion (opening 72e) is inserted into the opening 72d and scattering in an unintended direction, such as toward the front of the tank body 6 or the rear of the tailgate 7. Furthermore, when the tailgate 7 is closed, the insertion portion is pushed open when the engaging portion is inserted, so that the engagement can be easily performed.

[0032] A lock detection unit that detects the open and closed states of the lock cylinder 71 is provided near the cylinder rod 71a of the lock cylinder 71. In this embodiment, the lock detection unit includes an unlocked detection sensor 75 that detects the unlocked state of the lock cylinder 71 and a closed lock detection sensor 76 that detects the closed and unlocked state of the lock cylinder 71. The lock detection unit is installed on a patch 81b of the hatch guard 81 along with the lock cylinder 71. This allows the lock cylinder 71 and the lock detection unit to be welded to the guard body 81a after confirming that the positional relationship between them is appropriate, ensuring accurate lock detection. The unlocked detection sensor 75 and the closed lock detection sensor 76 can be, for example, a proximity sensor. For example, when the lock cylinder 71 is fully retracted (the state indicated by the solid line in FIG. 3 ), the unlocked state of the lock cylinder 71 is detected by the unlocked detection sensor 75, and the unlocked detection sensor 75 turns on. When the lock cylinder 71 is in any other state, the unlocked detection sensor 75 turns off. Furthermore, when the lock cylinder 71 is in an extended state (the state shown by the dashed line in Figure 3), the lock closed detection sensor 76 detects that the lock cylinder 71 is in a locked closed state, and the lock closed detection sensor 76 turns on. When the lock cylinder 71 is in any other state, the lock closed detection sensor 75 turns off.

[0033] A tailgate closed detection sensor (tailgate closed detection unit) 77 that detects the closed state of the tailgate 7 is provided at the rear end of the tank body 6. A proximity sensor, for example, can be used as the tailgate closed detection sensor 77. For example, when the tank-side flange 6a of the tank body 6 and the gate-side flange 7a of the tailgate 7 are in contact with each other via the packing 73 (the state shown in FIG. 5), the tailgate closed detection sensor 77 detects the completion of the closing operation of the tailgate 7 and turns on. When the tank-side flange 6a and the gate-side flange 7a are in any other state, the tailgate closed detection sensor 77 turns off. The tailgate closed detection sensor 77 is located further forward of the packing 73 than the vehicle.

[0034] 1 and 2, a tank pressurization / depressurization pipe 41 is connected to the top of the tank body 6 of the receiver tank 5, and by operating the suction device 1, the air in the receiver tank 5 can be sucked out to reduce the pressure, or conversely, air can be sent into the receiver tank 5 to pressurize it. A portion of the tank pressurization / depressurization pipe 41 is made of a flexible material such as a flexible hose to accommodate the rotational movement of the receiver tank 5. Also, on the underside of the tailgate 7, there are provided a suction port 11 with an on-off valve that serves as a suction port for objects to be collected, and a discharge port 12 with an on-off valve that serves as a discharge port for objects to be collected.

[0035] The receiver tank 5 is pivotally supported on the subframe 4 via a tilting pin 14 so that it can tilt freely, and a tilting cylinder 15 is disposed between the subframe 4 and the receiver tank 5. By extending or contracting this tilting cylinder 15, the receiver tank 5 rotates upright or down around the tilting pin 14.

[0036] When the suction vehicle 2 sucks up the object to be collected into the receiver tank 5, the air inside the receiver tank 5 is reduced in pressure by operating the suction device 1, and the object to be collected is sucked into the receiver tank 5 from the outside through a suction hose (not shown) connected to the suction port 11 with an opening / closing valve.

[0037] On the other hand, when the suction vehicle 2 discharges the materials to be collected in the receiver tank 5 to a predetermined location (such as a sludge treatment plant), the air inside the receiver tank 5 is pressurized and the materials to be collected in the receiver tank 5 are discharged to the outside through a discharge hose (not shown) connected to the discharge port 12 with an on-off valve. The materials to be collected in the receiver tank 5 can also be discharged by opening the tailgate 7 and rotating the receiver tank 5 upright.

[0038] To pressurize or depressurize the receiver tank 5 in this manner, a suction device 1 is mounted between the cab 16 of the suction vehicle 2 and the receiver tank 5. The suction device 1 includes, for example, an upstream catcher, a catcher tank 60, a blower 40, and various valves, piping, and other equipment, all of which are not shown in detail. The blower 40 is, for example, a Roots type, and is connected to a PTO (power take-off) that extracts driving force from an engine (not shown) of the suction vehicle 2, so that it is driven by the engine's driving force. However, the configuration of the suction device 1 is not limited to this. For example, a vacuum pump (e.g., a water seal pump or a vane pump) may be used instead of the blower 40.

[0039] As shown in Figure 1, the suction vehicle 2 is equipped with an operation panel 19 on which meters, switches, operating levers, etc. are concentrated. An operating lever 27 for operating the opening / closing cylinder 9 and the tilting cylinder 15 is arranged on this operation panel 19. Operation of this operating lever switches the hydraulic circuit O, which will be described later, to contract or extend the opening / closing cylinder 9 and the tilting cylinder 15. The operation panel 19 is also equipped with a warning buzzer, warning lights, panel lights, tachometer lights, etc.

[0040] In this embodiment, the opening / closing cylinder 9 and the tilting cylinder 15 can be operated with a single operating lever 27. Furthermore, as will be described later, the lock cylinder 71 can also be operated with the operating lever 27. The operating lever 27 can be operated, for example, left and right and up and down around the position shown in the figure. For example, when the operating lever 27 is operated upward, the tilting cylinder 15 extends, causing the receiver tank 5 to stand up (dump up). When the operating lever 27 is operated downward, the tilting cylinder 15 retracts, causing the receiver tank 5 to fall down (dump down). When the operating lever 27 is operated rightward, the opening / closing cylinder 9 extends, causing the tailgate 7 to open (gate open). When the operating lever 27 is operated leftward, the opening / closing cylinder 9 retracts, causing the tailgate 7 to close (gate close).

[0041] Next, the hydraulic circuit O for operating the open / close cylinder 9, tilting cylinder 15, and lock cylinder 71 in the suction vehicle 2 will be described with reference to Figure 7. As shown in Figure 7, the hydraulic circuit O includes a hydraulic pump P as a hydraulic source, an oil reservoir T, and a main valve unit M that houses solenoid valves V1, V2, and V3 in a common valve block. As mentioned above, the hydraulic pump P is connected to the PTO, and as the engine speed increases, the hydraulic pump P speed also increases, increasing the discharge volume.

[0042] The main valve unit M is disposed, for example, behind the operation panel 19, and is connected by hydraulic piping to the open / close cylinder 9, tilting cylinder 15, and lock cylinder 71. The solenoid valves V1, V2, and V3 are, for example, six-port, three-position manual directional control valves, and their positions are switched by energizing the solenoids (see Figure 8).

[0043] When the solenoid SOLa is excited by energization from the sequence circuit S (see FIG. 8), the electromagnetic valve V1 switches to the first communication position (left position in the figure) and supplies hydraulic oil from the hydraulic pump P to the rod-side oil chamber of the tilting cylinder 15. This causes the tilting cylinder 15 to contract. On the other hand, when the solenoid SOLb is excited, the electromagnetic valve V1 switches to the second communication position (right position in the figure) and supplies hydraulic oil from the hydraulic pump P to the cap-side oil chamber of the tilting cylinder 15. This causes the tilting cylinder 15 to extend.

[0044] When hydraulic oil is supplied to the cap-side oil chamber of the tilting cylinder 15 in this way, the tilting cylinder 15 extends, raising the receiver tank 5. On the other hand, when hydraulic oil is supplied to the rod-side oil chamber of the tilting cylinder 15, the tilting cylinder 15 contracts, lowering the receiver tank 5. When the solenoid valves V1, V2, and V3 are in the neutral position, the hydraulic oil returns to the oil reservoir T.

[0045] When the solenoid SOLe is excited by energization from the sequence circuit S, the electromagnetic valve V2 switches to the first communication position (left position in the figure) and supplies hydraulic oil from the hydraulic pump P to the rod-side oil chamber of the opening-closing cylinder 9. This causes the opening-closing cylinder 9 to contract. On the other hand, when the solenoid SOLf is excited, the electromagnetic valve V2 switches to the second communication position (right position in the figure) and supplies hydraulic oil from the hydraulic pump P to the cap-side oil chamber of the opening-closing cylinder 9. This causes the opening-closing cylinder 9 to extend.

[0046] When hydraulic oil is supplied to the cap-side oil chamber of the opening-closing cylinder 9 in this way, the opening-closing cylinder 9 extends, causing the tailgate 7 to rotate around the hinge pin 8 and opening the rear opening of the tank body 6. On the other hand, when hydraulic oil is supplied to the rod-side oil chamber of the opening-closing cylinder 9, the opening-closing cylinder 9 contracts, causing the tailgate 7 to rotate around the hinge pin 8 and closing the rear opening of the tank body 6.

[0047] When the solenoid SOLg is excited by energization from the sequence circuit S, the electromagnetic valve V3 switches to the first communication position (the left position in the figure) and supplies hydraulic oil from the hydraulic pump P to the rod-side oil chamber of the lock cylinder 71. This causes the lock cylinder 71 to contract. On the other hand, when the solenoid SOLh is excited, the electromagnetic valve V3 switches to the second communication position (the right position in the figure) and supplies hydraulic oil from the hydraulic pump P to the cap-side oil chamber of the lock cylinder 71. This causes the lock cylinder 71 to extend.

[0048] When hydraulic oil is supplied to the cap-side oil chamber of the lock cylinder 71 in this manner, the lock cylinder 71 extends, causing the tip of the cylinder rod 71a to engage with the boss portion 72 and switching the gate lock mechanism 70 to the locked state. As a result, the tailgate 7 is fastened to the tank-side flange 6a of the tank main body 6, preventing the tailgate 7 from opening or closing. On the other hand, when hydraulic oil is supplied to the rod-side oil chamber of the lock cylinder 71, the lock cylinder 71 contracts, causing the tip of the cylinder rod 71a to disengage from the boss portion 72 and switching the gate lock mechanism 70 to the unlocked state. As a result, the tailgate 7 is released from being fastened to the tank-side flange 6a of the tank main body 6, allowing the tailgate 7 to open or close.

[0049] Next, the sequence circuit S for operating the opening / closing cylinder 9, tilting cylinder 15, and lock cylinder 71 in the suction vehicle 2 will be described with reference to Fig. 8. This sequence circuit S serves as a control unit for controlling the opening / closing cylinder 9 and lock cylinder 71. Fig. 8 shows a part of the sequence circuit S for operating the opening / closing cylinder 9, tilting cylinder 15, and lock cylinder 71, and the sequence circuit S is equipped with the four contacts 27d to 27g of the operating lever 27, the solenoids SOLa, SOLb, SOLe, SOLf, SOLg, and SOLh of the hydraulic circuit O described above, the left and right lock open detection sensors 75, 75, the left and right lock close detection sensors 76, 76, the left and right tailgate close detection sensors 77, 77, relays R1 and R2, relay contacts r1 to r6, etc.

[0050] As relay R1 turns on and off, the corresponding relay contacts r1 to r4 open and close. When relay R1 turns on, relay contacts r1 and r3 close, and relay contacts r2 and r4 open. On the other hand, when relay R2 turns off, relay contacts r1 and r3 open, and relay contacts r2 and r4 close. Also, as relay R2 turns on and off, the corresponding relay contacts r5 and r6 open and close. When relay R2 turns on, relay contact r5 opens, and relay contact r6 closes. On the other hand, when relay R2 turns off, relay contact r5 closes, and relay contact r6 opens.

[0051] Relay R1 is switched on when both left and right lock-open detection sensors 75 are on, and switched off when at least one of the left and right lock-open detection sensors 75 is off. Relay R2 is switched on when both left and right tailgate closing detection sensors 77 are on, and switched off when at least one of the left and right tailgate closing detection sensors 77 is off. Furthermore, when both left and right lock-open detection sensors 75 are on, a status indicator lamp 82 installed on, for example, the operation panel 19, lights up. When at least one of the left and right lock-open detection sensors 75 is off, the status indicator lamp 82 is turned off. The illumination of the status indicator lamp 82 notifies the operator of the open state of the lock cylinder 71.

[0052] When one of the contacts 27d to 27g is closed in response to up, down, left, or right operation of the operating lever 27, hydraulic oil can be supplied to the opening / closing cylinder 9, the tilting cylinder 15, and the lock cylinder 71. As a result, when the opening / closing cylinder 9, the tilting cylinder 15, and the lock cylinder 71 each extend or retract, the tailgate 7 of the receiver tank 5 is opened or closed, the receiver tank 5 is raised or lowered, and the gate lock mechanism 70 is switched between a locked state and an unlocked state.

[0053] For example, when the operating lever 27 is operated upward, the contact 27e is closed and the solenoid SOLb is energized. This switches the electromagnetic valve V1 to the second communication position (the right-hand position in FIG. 7), hydraulic oil is supplied to the cap-side oil chamber of the tilting cylinder 15, the tilting cylinder 15 is extended, and the receiver tank 5 is raised. On the other hand, when the operating lever 27 is operated downward, the contact 27d is closed and the solenoid SOLa is energized. This switches the electromagnetic valve V1 to the first communication position (the left-hand position in FIG. 7), hydraulic oil is supplied to the rod-side oil chamber of the tilting cylinder 15, the tilting cylinder 15 is retracted, and the receiver tank 5 is lowered.

[0054] Furthermore, when the operating lever 27 is operated to the right, the contact 27f is closed. At this time, if the contact r1 is closed, the solenoid SOLf is energized, the electromagnetic valve V2 is switched to the second communication position (the right position in FIG. 7), hydraulic oil is supplied to the cap-side oil chamber of the opening / closing cylinder 9, the opening / closing cylinder 9 is extended, and the tailgate 7 is not opened. However, if the contact r1 is open, the solenoid SOLf is not energized, hydraulic oil is not supplied to the cap-side oil chamber of the opening / closing cylinder 9, the opening / closing cylinder 9 is not extended, and the tailgate 7 is not opened.

[0055] On the other hand, when the operating lever 27 is operated to the left, the contact 27g is closed. At this time, if the contact r6 is closed, the solenoid SOLe is energized. Also, when the operating lever 27 is operated to the left, if the contacts r5 and r3 are closed, the solenoid SOLe is energized. When the solenoid SOLe is energized, the electromagnetic valve V2 is switched to the first communication position (the left position in FIG. 7), hydraulic oil is supplied to the rod-side oil chamber of the opening / closing cylinder 9, the opening / closing cylinder 9 contracts, and the tailgate 7 is closed. However, when at least one of the contacts r3 and r5 is open and r6 is open, the solenoid SOLe is not energized, hydraulic oil is not supplied to the rod-side oil chamber of the opening / closing cylinder 9, the opening / closing cylinder 9 does not contract, and the tailgate 7 is not closed.

[0056] Furthermore, when the operating lever 27 is operated to the right, if contact r2 is closed, the solenoid SOLg is energized. When the operating lever 27 is operated to the left, if contacts r5 and r4 are closed, the solenoid SOLg is energized. When the solenoid SOLg is energized, the electromagnetic valve V3 is switched to the first communication position (the left position in FIG. 7 ), hydraulic oil is supplied to the rod-side oil chamber of the lock cylinder 71, the lock cylinder 71 contracts, and the gate lock mechanism 70 is switched to the unlocked state. This releases the tailgate 7 from being fastened to the tank-side flange 6a of the tank body 6, allowing the tailgate 7 to be opened and closed. However, when contact r2 is open and at least one of contacts r4 and r5 is open, the solenoid SOLg is not energized, hydraulic oil is not supplied to the rod-side oil chamber of the lock cylinder 71, the lock cylinder 71 does not contract, and the gate lock mechanism 70 is not switched to the unlocked state.

[0057] On the other hand, when the operating lever 27 is operated to the left, if the contact r6 is closed, the solenoid SOLh is energized, the electromagnetic valve V3 is switched to the second communication position (the right position in FIG. 7), hydraulic oil is supplied to the cap-side oil chamber of the lock cylinder 71, the lock cylinder 71 is extended, and the gate lock mechanism 70 is switched to the locked state. As a result, the tailgate 7 is fastened to the tank-side flange 6a of the tank body 6, and the tailgate 7 cannot be opened or closed. However, if the contact r6 is open, the solenoid SOLh is not energized, hydraulic oil is not supplied to the cap-side oil chamber of the lock cylinder 71, the lock cylinder 71 is not extended, and the gate lock mechanism 70 is not switched to the locked state.

[0058] In this embodiment, the suction vehicle 2 configured as described above includes an opening / closing cylinder (tailgate opening / closing unit) 9 that opens and closes the tailgate 7, a lock cylinder (lock unit) 71 that mechanically restricts the opening operation of the tailgate 7 from a closed state, a sequence circuit (control unit) S that controls the operation of the opening / closing cylinder 9 and the lock cylinder 71, an operating lever (tailgate operating unit) 27 that issues an operation command for the opening / closing cylinder 9 to the sequence circuit S, and a lock detection unit that detects at least one of a locked closed state in which the opening operation of the tailgate 7 is restricted by the lock cylinder 71 and a locked open state in which the opening operation of the tailgate 7 is not restricted by the lock cylinder 71. The sequence circuit S is configured to open the lock cylinder 71 based on the detection state of the lock detection unit when the operating lever 27 is operated. Specifically, the sequence circuit S inhibits the operation of the opening / closing cylinder 9 based on the detection state of the lock detection unit. Furthermore, if the operating lever 27 is being operated when the lock detector detects that the lock cylinder 71 is in an unlocked state, the sequence circuit S releases the inhibition of the operation of the opening / closing cylinder 9 and opens or closes the tailgate 7. This point will be described below with reference to Figures 7, 8, etc.

[0059] As described above, when the tailgate 7 is opened, the operating lever 27 is operated to the right. During such operation of the operating lever 27, if the unlocked detection sensor 75, which serves as a lock detector, does not detect that the lock cylinder 71 is in the unlocked state, the extension of the opening / closing cylinder 9 is inhibited and the lock cylinder 71 is opened. More specifically, as shown in FIG. 8, when the operating lever 27 is operated to the right, the contact r1 is open, so the solenoid SOLf is not immediately excited, the solenoid valve V2 is not switched to the second communicating position (the right-hand position in FIG. 7), no hydraulic oil is supplied to the cap-side oil chamber of the opening / closing cylinder 9, and the extension of the opening / closing cylinder 9 is inhibited. In other words, when the unlocked detection sensor 75 does not detect that the lock cylinder 71 is in the unlocked state, the relay R1 is turned off, and the extension of the opening / closing cylinder 9 is inhibited while the contact r1 is open.

[0060] At this time, the contact r2 is closed and the solenoid SOLg is excited, so the solenoid valve V3 switches to the first communication position (the left position in FIG. 7 ). Hydraulic oil is supplied to the rod-side oil chamber of the lock cylinder 71, causing the lock cylinder 71 to contract and disengage the tip of the cylinder rod 71a from the boss portion 72. This switches the gate lock mechanism 70 to the unlocked state. When the unlock detection sensor 75 detects that the lock cylinder 71 is in the unlocked state, the relay R1 turns on, the contact r1 closes, the solenoid SOLf is excited, and the status notification lamp 82 lights up. This switches the solenoid valve V2 to the second communication position (the right position in FIG. 7 ). Hydraulic oil is supplied to the cap-side oil chamber of the opening / closing cylinder 9, causing the opening / closing cylinder 9 to extend. This extension of the opening / closing cylinder 9 causes the tailgate 7 to rotate around the hinge pin 8, opening the rear opening of the tank body 6.

[0061] Furthermore, when the tailgate 7 is closed, the operating lever 27 is operated leftward. When the operating lever 27 is operated in this manner, if the unlock detection sensor 75 does not detect that the lock cylinder 71 is in the unlocked state, the retraction of the opening / closing cylinder 9 is inhibited and the lock cylinder 71 is opened. In detail, as shown in FIG. 8, when the operating lever 27 is operated leftward, the contact r3 is open, so the solenoid SOLe is not immediately excited, the solenoid valve V2 is not switched to the first communicating position (the left position in FIG. 7), no hydraulic oil is supplied to the rod-side oil chamber of the opening / closing cylinder 9, and the retraction of the opening / closing cylinder 9 is inhibited. In other words, when the unlock detection sensor 75 does not detect that the lock cylinder 71 is in the unlocked state, the relay R1 is turned off, and the retraction of the opening / closing cylinder 9 is inhibited while the contact r3 is open.

[0062] At this time, the contacts r5 and r4 are closed, and the solenoid SOLg is excited. Since the solenoid SOLg is excited, the electromagnetic valve V3 switches to the first communication position (the left position in FIG. 7 ). Hydraulic oil is supplied to the rod-side oil chamber of the lock cylinder 71, causing the lock cylinder 71 to contract and disengage the tip of the cylinder rod 71a from the boss portion 72. This switches the gate lock mechanism 70 to the unlocked state. When the unlock detection sensor 75 detects that the lock cylinder 71 is in the unlocked state, the relay R1 turns on, the contact r3 closes, the solenoid SOLe is excited, and the status notification lamp 82 lights up. This switches the electromagnetic valve V2 to the first communication position (the left position in FIG. 7 ). Hydraulic oil is supplied to the rod-side oil chamber of the opening / closing cylinder 9, causing the opening / closing cylinder 9 to contract. By such contraction of the opening / closing cylinder 9, the tailgate 7 rotates about the hinge pin 8, and the rear opening of the tank body 6 is closed.

[0063] According to this embodiment, the tailgate 7 can be easily opened and closed while preventing damage to the gate lock mechanism 70 of the tailgate 7. Specifically, if the unlock detection sensor 75 does not detect that the lock cylinder 71 is in the unlocked state when the operating lever 27 is operated, the sequence circuit S automatically opens the lock cylinder 71, thereby preventing damage to the gate lock mechanism 70. Even when the lock cylinder 71 is in a half-open state between the unlocked state and the closed lock state, the unlock detection sensor 75 does not detect that the lock cylinder 71 is in the unlocked state. Therefore, even in this case, the lock cylinder 71 is opened, preventing damage to the gate lock mechanism 70. Furthermore, after the unlock detection sensor 75 detects that the lock cylinder 71 is in the unlocked state, the tailgate 7 is opened without any change. Therefore, there is no need to switch between operating the gate lock mechanism 70 and operating the tailgate 7, and the tailgate 7 can be opened and closed with a single operation.

[0064] In this embodiment, a status notification lamp 82 is used to notify the driver based on the detection state of the unlocked detection sensor 75. Specifically, when the unlocked detection sensor 75 is on, the status notification lamp 82 is illuminated. This prevents the tailgate 7 from being opened accidentally while the lock cylinder 71 is being opened.

[0065] Furthermore, in this embodiment, the tank body 6 is provided with hatch guards 81 that extend to the sides and / or downward of the vehicle around the peripheral edge of the tank-side flange 6a of the tank body 6, and the lock-open detection sensor 75 is disposed near the hatch guard 81 and further forward of the vehicle than the hatch guard 81. This prevents the lock-open detection sensor 75 from becoming soiled by sludge or the like that has overflowed from the tank body 6, making it unable to detect the open / closed state of the lock cylinder 71. Note that, although the hatch guards 81 are provided on the sides and downward of the vehicle in this embodiment, the hatch guards 81 may be provided on only one of the sides and downward of the vehicle.

[0066] Furthermore, in this embodiment, a tailgate closed detection sensor (tailgate closed detection unit) 77 is provided that is electrically connected to the sequence circuit S and detects the closed state of the tailgate 7. When the tailgate closed detection sensor 77 detects the closed state of the tailgate 7, the sequence circuit S is configured to lock and close the lock cylinder 71 if the tailgate 7 is being closed by the operating lever 27, that is, if the operating lever 27 is being operated to the left. By operating the tailgate 7 to close by the operating lever 27 as described above, the opening / closing cylinder 9 contracts, and the rear opening of the tank body 6 is closed by the tailgate 7. If the closing operation of the tailgate 7 by the operating lever 27 is continuing when the closed state of the tailgate 7 is detected, the lock cylinder 71 is configured to lock and close based on this closing operation of the tailgate 7.

[0067] Specifically, when the tailgate closing detection sensor 77 detects that the tailgate 7 is closed, relay R2 turns on, contact r5 opens, contact r6 closes, and solenoids SOLe and SOLh are energized. When solenoid SOLe is energized, electromagnetic valve V2 switches to the first communication position (left position in FIG. 7), hydraulic oil is supplied to the rod-side oil chamber of the opening / closing cylinder 9, and the opening / closing cylinder 9 contracts. The contraction of the opening / closing cylinder presses the tailgate 7 against the tank-side flange 6a of the tank body, preventing leakage of the collected materials before the tailgate 7 is completely secured by the lock cylinder 71. When solenoid SOLh is energized, electromagnetic valve V3 switches to the second communication position (right position in FIG. 7), hydraulic oil is supplied to the cap-side oil chamber of the lock cylinder 71, and the lock cylinder 71 extends. By extending the lock cylinder 71, the tip of the cylinder rod 71a engages with the boss portion 72, switching the gate lock mechanism 70 to the locked state, and fastening the tailgate 7 to the tank side flange 6a of the tank body 6.

[0068] In this way, when the tailgate 7 is closed, by continuing to perform the closing operation of the tailgate 7 even after the closed state of the tailgate 7 has been detected, the lock cylinder 71 is closed, and the gate lock mechanism 70 can be switched to the locked state, and the gate lock mechanism 70 can be switched to the locked state by the operating lever 27. This eliminates the need to switch between the closing operation of the tailgate 7 and the closing operation of the gate lock mechanism 70, and the gate lock mechanism 70 can be switched to the locked state with a single operation.

[0069] The embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. The technical scope of the present invention is not interpreted solely by the above-described embodiments, but is defined by the claims. The technical scope of the present invention also includes all modifications within the meaning and scope of the claims.

[0070] In the above embodiment, the opening and closing operation of the opening and closing cylinder 9 and the tilting operation of the tilting cylinder 15 are performed by a common operating lever 27, but this is not limiting, and the opening and closing operation of the opening and closing cylinder 9 and the tilting operation of the tilting cylinder 15 may be performed by separate operating devices. Also, an operating device for opening and closing the lock cylinder 71 may be provided separately from the operating lever 27 of the above embodiment.

[0071] In the above embodiment, the lock cylinder 71 is provided on the tank main body 6 side, but this is not limiting, and the lock cylinder 71 may be provided on the tailgate 7 side. When the lock cylinder 71 is provided on the tailgate 7 side, it is preferable to provide an engagement portion on the tank main body 6 with which the cylinder rod 71a of the lock cylinder 71 engages, and to provide an opening on the tailgate 7 through which this engagement portion is inserted, and to cover this opening with a cover formed of a flexible member.

[0072] In the above embodiment, the unlocked detection sensor 75 that detects the unlocked state of the lock cylinder 71 and the closed detection sensor 76 that detects the closed state of the lock cylinder 71 are provided separately, but this is not limiting and a common sensor may be used to detect both the unlocked state and the closed state of the lock cylinder 71. Only one of the unlocked state or the closed state of the lock cylinder 71 may be detected, and the absence of detection may be determined to be the other state. Furthermore, although proximity sensors are used as the unlocked detection sensor 75, the closed detection sensor 76, and the tailgate closed detection sensor 77, sensors other than proximity sensors may also be used.

[0073] In the above embodiment, the hatch guard 81 is integrally formed by welding the patch 81b and the side plate 81c to the guard main body 81a, but this is not limited to this. The hatch guard 81 may be formed by processing such as bending or cutting out a single steel plate, or the patch 81b and the side plate 81c may be formed to be removable using bolts, etc.

[0074] In the above embodiment, the operation of the opening / closing cylinder 9 and the lock cylinder 71 is controlled by a sequence circuit S (control unit) controlled by relays, but this is not limited to this, and the operation of the opening / closing cylinder 9 and the lock cylinder 71 may also be controlled by a programmable logic controller (PLC) controlled by a program. [Explanation of symbols]

[0075] 2 Suction car 5 Receiver Tank 6 Tank body 6a Tank side flange 7. Tailgate 7a Gate side flange 9 Opening and closing cylinder (tailgate opening and closing part) 27 Operating lever (tailgate operating section) 70 Gate lock mechanism 71 Lock cylinder (lock part) 75 Lock open detection sensor (lock detection section) 82 Status indicator lamp S Sequence circuit (control section)

Claims

1. A suction vehicle equipped with a tank body having a rear opening and a tailgate that can open and close the rear opening, a tailgate opening / closing unit that opens and closes the tailgate; a locking portion that mechanically restricts an opening operation of the tailgate from a closed state of the tailgate; a control unit that controls the operation of the tailgate opening / closing unit and the locking unit; a tailgate operation unit that gives an operation instruction of the tailgate opening / closing unit to the control unit; a lock detection unit that detects at least one of a locked closed state in which the lock unit restricts the opening operation of the tailgate and a locked open state in which the lock unit does not restrict the opening operation of the tailgate, The control unit is characterized in that, when the tailgate operation unit is operated, the control unit causes the lock unit to perform an unlocking operation based on the detection state of the lock detection unit.

2. The suction vehicle according to claim 1, The control unit inhibits operation of the tailgate opening / closing unit based on the detection state of the lock detection unit.

3. The suction vehicle according to claim 2, When the lock detection unit detects the unlocked state of the lock unit, if the tailgate operation unit is being operated, the control unit releases the inhibition of operation of the tailgate opening / closing unit and opens and closes the tailgate.

4. The suction vehicle according to claim 1, A suction vehicle that issues a notification based on the detection state of the lock detection unit.

5. The suction vehicle according to claim 1, The tank body includes a hatch guard extending to the side and / or downward of the vehicle around the periphery of the rear opening, The suction vehicle is characterized in that the lock detection unit is disposed near the hatch guard and further forward than the hatch guard.

6. The suction vehicle according to claim 1, an engaging portion with which the locking portion is engaged in the locked closed state and the tailgate is closed is provided on one of the tailgate and the tank body; an opening into which the engaging portion is inserted when the tailgate is in a closed state is provided in the other of the tailgate and the tank body; A suction vehicle characterized in that the opening is covered by a cover formed of a flexible material and having an insertion portion that can be pushed open, and when the engagement portion is inserted into the opening, the engagement portion pushes open the insertion portion.

7. The suction vehicle according to any one of claims 1 to 6, a tailgate closed detection unit electrically connected to the control unit and configured to detect a closed state of the tailgate; The control unit performs a locking operation of the lock unit when the tailgate closing detection unit detects that the tailgate is closed and the tailgate operation unit is operating to close.

Images