Wing opening / closing device

Abstract

To protect a wing door.SOLUTION: A wing opening / closing device has a first hydraulic cylinder which is fitted to a first end of a wing door and comprises a first open-side oil chamber, and a second hydraulic cylinder which is fitted to a second end of the wing door and comprises a second open-side oil chamber. The wing opening / closing device has a shunt valve which is connected to a discharge oil passage of a hydraulic pump, connected to the first open-side oil chamber through a first oil passage, and connected to the second open-side oil chamber through a second oil passage. The wing opening / closing device has a relay which is provided at a power supply circuit for an electric motor driving the hydraulic pump, and operates between a connection state for supplying electric power to the electric motor and a disconnection state for cutting off the power supply. The relay operates from the connection state to the disconnection state if the working hydraulic pressure in the first oil passage exceeds a threshold with the wing door opened.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a wing opening and closing device. [Background technology]

[0002] A vehicle such as a truck or a trailer has a box-shaped loading platform with wing doors on the left and right sides. A wing door opening / closing device consisting of a hydraulic cylinder is attached to the box-shaped loading platform with wing doors. This wing door opening / closing device opens the wing doors by extending the hydraulic cylinder and closes the wing doors by retracting the hydraulic cylinder (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-46128 A Summary of the Invention [Problem to be solved by the invention]

[0004] In addition, when storing cargo such as a transport cart on a box-shaped loading platform, it is common to attach lashing belts to rails provided on the left and right wing doors and fasten the lashing belts to secure the cargo. In this way, the situation in which the cargo is secured by the lashing belts is a situation in which the left and right wing doors are connected to each other via the lashing belts.

[0005] However, when the left and right wing doors are connected to each other, extending the hydraulic cylinder to open the wing door can cause deformation of the wing door. In other words, if the hydraulic cylinder is extended without removing the lashing belt, the partially restrained wing door is forced open, causing the wing door to twist and deform. There is a need to protect the wing door from such deformation. [Means for solving the problem]

[0006] According to the present disclosure, a wing opening / closing device is a wing opening / closing device for opening and closing a wing door of a luggage compartment, the wing opening / closing device comprising: a first hydraulic cylinder attached to a first end of the wing door in a longitudinal direction and having a first opening-side oil chamber to which hydraulic oil is supplied when the wing door is opened; a second hydraulic cylinder attached to a second end of the wing door in a longitudinal direction and having a second opening-side oil chamber to which hydraulic oil is supplied when the wing door is opened; a diversion valve including an input port connected to a discharge oil passage of a hydraulic pump, a first output port connected to the first opening-side oil chamber via a first oil passage, and a second output port connected to the second opening-side oil chamber via a second oil passage; and a relay provided in a power supply circuit of an electric motor that drives the hydraulic pump, the relay operating between a connected state in which current is applied to the electric motor and a disconnected state in which current is cut off, the relay operating from the connected state to the disconnected state when the hydraulic oil pressure in the first oil passage exceeds a threshold value under a situation in which the wing door is opened. Effect of the Invention

[0007] According to the present disclosure, the wing door can be protected. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of a vehicle equipped with a box-shaped loading platform. [Diagram 2] FIG. 1 is a diagram showing an example of a vehicle equipped with a box-shaped loading platform. [Diagram 3] FIG. 1 is a diagram showing an example of a vehicle equipped with a box-shaped loading platform. [Figure 4] FIG. 2 is a diagram showing an example of a hydraulic system provided in the wing opening / closing device. [Figure 5A] 1A and 1B are diagrams illustrating an example of the structure and operating state of a flow dividing and collecting valve. [Figure 5B] 1A and 1B are diagrams illustrating an example of the structure and operating state of a flow dividing and collecting valve. [Figure 6A] 1A and 1B are diagrams illustrating an example of the structure and operating state of a flow dividing and collecting valve. [Figure 6B] 1A and 1B are diagrams illustrating an example of the structure and operating state of a flow dividing and collecting valve. [Figure 7] FIG. 2 is a diagram showing an example of an energization system provided in a wing opening / closing device. [Figure 8] FIG. 4 is a diagram showing an operating state of the energization system when normally open. [Figure 9A] FIG. 13 is a diagram showing the operating state of the cylinder when normally open. [Figure 9B] FIG. 13 is a diagram showing an increase in hydraulic pressure during normal release. [Figure 10] FIG. 13 is a diagram showing the operation state of the current supply system when the restraint is released. [Figure 11A] FIG. 13 is a diagram showing an operating state of the cylinder when the restraint is released. [Figure 11B] FIG. 13 is a diagram showing an increase in hydraulic oil pressure when restraint is released. [Figure 12] FIG. 4 is a diagram showing an operation state of the current supply system when a high load is released. [Figure 13A] FIG. 13 is a diagram showing an operating state of a cylinder when a high load is released. [Figure 13B] FIG. 13 is a diagram showing an increase in hydraulic pressure when a high load is released. [Figure 14] FIG. 13 is a diagram showing a current supply system for a wing opening / closing device according to another embodiment. [Figure 15] FIG. 13 is a diagram showing a current supply system for a wing opening / closing device according to another embodiment. [Figure 16A] FIG. 13 is a diagram showing a box-shaped carrier according to another embodiment. [Figure 16B] FIG. 13 is a diagram showing a box-shaped carrier according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same or substantially the same configurations and elements will be denoted by the same reference numerals and repeated description will be omitted.

[0010] First Embodiment <Box-shaped loading platform> 1 to 3 are diagrams showing an example of a vehicle 11 equipped with a box-shaped cargo bed 10. Fig. 1 is a perspective view showing the vehicle 11 with the left wing door 20 open, and Fig. 2 is a rear view showing the vehicle 11 with the left and right wing doors 20, 30 open. Fig. 3 is a partial cross-sectional view of the vehicle 11 showing the loading status of luggage X.

[0011] As shown in Figures 1 to 3, a vehicle 11, which is a truck, has a box-shaped bed 10 with a luggage compartment 12 on the inside. The box-shaped bed 10, also called a wing body, has a floor frame 13 mounted on the chassis of the vehicle 11, a front frame 14 provided at the front end of the floor frame 13, and a rear frame 15 provided at the rear end of the floor frame 13. A floor plate 16 is attached to the floor frame 13, a front wall 17 is attached to the front frame 14, and an opening / closing door 18 is attached to the rear frame 15. In addition, a support beam 19 extending in the front-rear direction of the vehicle 11 is provided in the upper center of the front frame 14 and the rear frame 15.

[0012] The box-type cargo bed 10 has a gate plate 21 swingably mounted on the left side of the floor frame 13, and a gate plate 31 swingably mounted on the right side of the floor frame 13. The box-type cargo bed 10 also has a left wing door 20 swingably mounted on the support beam 19, and a right wing door 30 swingably mounted on the support beam 19. The wing doors 20, 30, also called wing roofs, have ceiling portions 22, 32 that form the ceiling of the box-type cargo bed 10, and side wall portions 23, 33 that form the sides of the box-type cargo bed 10.

[0013] In order to open and close the left wing door 20, a rear cylinder (first hydraulic cylinder) C1Rr is attached to a rear end (first end) 24 of the wing door 20 in the longitudinal direction. A front cylinder (second hydraulic cylinder) C1Fr is attached to a front end (second end) 25 of the wing door 20 in the longitudinal direction. The rear end 24 of the wing door 20 is located further rearward in the vehicle than the front end 25 of the wing door 20. A cylinder tube 26a of the rear cylinder C1Rr is swingably attached to an upper portion of the rear frame 15, and a piston rod 26b of the rear cylinder C1Rr is swingably attached to the rear end 24 of the wing door 20. A cylinder tube 27a of the front cylinder C1Fr is swingably attached to an upper portion of the front frame 14, and a piston rod 27b of the front cylinder C1Fr is swingably attached to the front end 25 of the wing door 20.

[0014] The left wing door 20 can be opened upward to a fully open position by extending the piston rods 26b, 27b of the rear cylinder C1Rr and the front cylinder C1Fr. On the other hand, the left wing door 20 can be closed downward to a fully closed position by contracting the piston rods 26b, 27b of the rear cylinder C1Rr and the front cylinder C1Fr. Note that Figures 1 and 2 show a state in which the left wing door 20 is opened to the fully open position, and Figure 3 shows a state in which the left wing door 20 is closed to the fully closed position.

[0015] Similarly, in order to open and close the right wing door 30, a rear cylinder (first hydraulic cylinder) C2Rr is attached to a rear end (first end) 34 of the wing door 30 in the longitudinal direction. A front cylinder (second hydraulic cylinder) C2Fr is attached to a front end (second end) 35 of the wing door 30 in the longitudinal direction. The rear end 34 of the wing door 30 is located further rearward in the vehicle than the front end 35 of the wing door 30. The structures of the rear cylinder C2Rr and the front cylinder C2Fr are the same as those of the rear cylinder C1Rr and the front cylinder C1Fr described above. That is, the cylinder tube 36a corresponds to the cylinder tube 26a, and the piston rod 36b corresponds to the piston rod 26b. The cylinder tube 37a corresponds to the cylinder tube 27a, and the piston rod 37b corresponds to the piston rod 27b.

[0016] As shown in FIG. 3, when loading luggage X such as a transport dolly onto the box-shaped loading platform 10, the luggage X is fixed using lashing belts 40, 42. To attach the lashing belts 40, 42 to the box-shaped loading platform 10, lashing rails 41 extending in the front-rear direction of the vehicle 11 are provided on the inner surfaces of the left and right wing doors 20, 30. Similarly, lashing rails 43 extending in the front-rear direction of the vehicle 11 are provided on the inner surfaces of the left and right gate plates 21, 31. Then, the ends of the lashing belts 40 are attached to the lashing rails 41 of the wing doors 20, 30, and the length of the lashing belts 40 is adjusted so as to restrain the luggage X. Similarly, the ends of the lashing belts 42 are attached to the lashing rails 43 of the gate plates 21, 31, and the length of the lashing belts 42 is adjusted so as to restrain the luggage X.

[0017] The fixing device for fixing the luggage X is not limited to the lashing belts 40, 42. For example, a rod-shaped lashing beam made of a metal material such as an aluminum alloy may be used as a fixing device for fixing the luggage X. Even when this lashing beam is used to restrain the luggage X, the lashing beam is attached to the lashing rails 41, 43 of the wing doors 20, 30 or the gate plates 21, 31. The lashing beam is also called a lashing bar or the like.

[0018] <Hydraulic system: configuration> Next, the hydraulic system 51 that extends and retracts the rear cylinders C1Rr, C2Rr and the front cylinders C1Fr, C2Fr will be described. Fig. 4 is a diagram showing an example of the hydraulic system 51 provided in the wing opening / closing device 50. In the following description, the rear cylinder C1Rr and the front cylinder C1Fr may be collectively referred to as cylinders C1Rr, C1Fr. Also, the rear cylinder C2Rr and the front cylinder C2Fr may be collectively referred to as cylinders C2Rr, C2Fr.

[0019] 4, the wing door opening / closing device 50 that opens and closes the wing doors 20, 30 has a hydraulic system 51 that expands and contracts the rear cylinders C1Rr, C2Rr and the front cylinders C1Fr, C2Fr. The hydraulic system 51 has a hydraulic pump 53 driven by an electric motor 52, the rear cylinder C1Rr and the front cylinder C1Fr that open and close the left wing door 20, and the rear cylinder C2Rr and the front cylinder C2Fr that open and close the right wing door 30.

[0020] The hydraulic system 51 also has a solenoid valve 60 located between the hydraulic pump 53 and the cylinders C1Fr, C1Rr, and a solenoid valve 70 located between the hydraulic pump 53 and the cylinders C2Fr, C2Rr. By controlling the solenoid valve 60, supply and discharge of hydraulic oil to the cylinders C1Rr, C1Fr is controlled, and the left wing door 20 can be opened and closed. By controlling the solenoid valve 70, supply and discharge of hydraulic oil to the cylinders C2Rr, C2Fr is controlled, and the right wing door 30 can be opened and closed.

[0021] The circuit structure for supplying hydraulic oil to the rear cylinder C1Rr and the front cylinder C1Fr is the same as the circuit structure for supplying hydraulic oil to the rear cylinder C2Rr and the front cylinder C2Fr. Therefore, in the following description, the circuit structure for the rear cylinder C1Rr and the front cylinder C1Fr that open and close the left wing door 20 will be described, and the circuit structure for the rear cylinder C2Rr and the front cylinder C2Fr that open and close the right wing door 30 will be assigned the same reference numerals and description thereof will be omitted.

[0022] The rear cylinder C1Rr connected to the left wing door 20 has a cylinder tube 26a, a piston 26c accommodated in the cylinder tube 26a, and a piston rod 26b fixed to the piston 26c. The inside of the cylinder tube 26a is divided into an opening-side oil chamber (first opening-side oil chamber) 28u and a closing-side oil chamber 28d by the piston 26d. The piston rod 26b of the rear cylinder C1Rr can be extended by supplying hydraulic oil to the opening-side oil chamber 28u and discharging hydraulic oil from the closing-side oil chamber 28d. On the other hand, the piston rod 26b of the rear cylinder C1Rr can be contracted by supplying hydraulic oil to the closing-side oil chamber 28d and discharging hydraulic oil from the opening-side oil chamber 28u.

[0023] The front cylinder C1Fr connected to the left wing door 20 has a cylinder tube 27a, a piston 27c accommodated in the cylinder tube 27a, and a piston rod 27b fixed to the piston 27c. The inside of the cylinder tube 27a is divided into an opening-side oil chamber (second opening-side oil chamber) 29u and a closing-side oil chamber 29d by the piston 27d. The piston rod 27b of the front cylinder C1Fr can be extended by supplying hydraulic oil to the opening-side oil chamber 29u and discharging hydraulic oil from the closing-side oil chamber 29d. On the other hand, the piston rod 27b of the front cylinder C1Fr can be contracted by supplying hydraulic oil to the closing-side oil chamber 29d and discharging hydraulic oil from the opening-side oil chamber 29u.

[0024] The solenoid valve 60 located between the hydraulic pump 53 and the cylinders C1Rr, C1Fr is a double solenoid type solenoid valve that operates in three positions: a stop position, an open position, and a closed position. When a solenoid 60u of the solenoid valve 60 is energized, the solenoid valve 60 is switched to the open position, and when a solenoid 60d of the solenoid valve 60 is energized, the solenoid valve 60 is switched to the closed position. When the energization of both solenoids 60u, 60d is cut off, the solenoid valve 60 is switched to the stop position.

[0025] The solenoid valve 60 is connected to a discharge oil passage 80 extending from a discharge port of the hydraulic pump 53 and a discharge oil passage 82 connected to an oil tank 81. The solenoid valve 60 is also connected to a supply / discharge passage 83u connected to the opening side oil chambers 28u, 29u of the cylinders C1Rr, C1Fr and a supply / discharge passage 83d connected to the closing side oil chambers 28d, 29d of the cylinders C1Rr, C1Fr.

[0026] The supply and discharge passage 83u has a supply and discharge oil passage 84u connected to the solenoid valve 60, a supply and discharge oil passage 85u connected to the open-side oil chamber 28u of the rear cylinder C1Rr, and a supply and discharge oil passage 86u connected to the open-side oil chamber 29u of the front cylinder C1Fr. The supply and discharge passage 83u also has a flow dividing and collecting valve 87 that connects the three supply and discharge oil passages 84u, 85u, and 86u to one another. The flow dividing and collecting valve 87 has a supply and discharge port 87A to which the supply and discharge oil passage 84u is connected, a supply and discharge port 87B to which the supply and discharge oil passage 85u is connected, and a supply and discharge port 87C to which the supply and discharge oil passage 86u is connected.

[0027] That is, the flow dividing and collecting valve (flow dividing valve) 87 has a supply and discharge port (input port) 87A connected to the discharge oil passage 80 of the hydraulic pump 53 via the supply and discharge oil passage 84u and the solenoid valve 60. The flow dividing and collecting valve 87 also has a supply and discharge port (first output port) 87B connected to the open-side oil chamber 28u via a supply and discharge oil passage (first oil passage) 85u, and a supply and discharge port (second output port) 87C connected to the open-side oil chamber 29u via a supply and discharge oil passage (second oil passage) 86u.

[0028] A pilot check valve 88u and a slow return valve 89u are provided in the supply and discharge oil passage 84u. The hydraulic pressure in the supply and discharge oil passage 90d described later is supplied to the pilot check valve 88u as a pilot pressure. As a result, the pilot check valve 88u operates as a check valve when the hydraulic pressure in the supply and discharge oil passage 90d is low, and operates in a communicating state when the hydraulic pressure in the supply and discharge oil passage 90d is high. A pressure switch (hydraulic switch, first hydraulic switch) S1Rr that operates between an ON state and an OFF state based on the hydraulic pressure in the supply and discharge oil passage 85u is connected to the supply and discharge oil passage 85u. Furthermore, a pressure switch (second hydraulic switch) S1Fr that operates between an ON state and an OFF state based on the hydraulic pressure in the supply and discharge oil passage 86u is connected to the supply and discharge oil passage 86u.

[0029] The supply and discharge oil passage 83d has a supply and discharge oil passage 90d connected to the solenoid valve 60. The supply and discharge oil passage 83d also has a supply and discharge oil passage 91d branching from the supply and discharge oil passage 90d and connected to the closing side oil chamber 28d of the rear cylinder C1Rr, and a supply and discharge oil passage 92d branching from the supply and discharge oil passage 90d and connected to the closing side oil chamber 29d of the front cylinder C1Fr. The supply and discharge oil passage 90d is provided with a pilot check valve 93d. The hydraulic pressure in the supply and discharge oil passage 84u is supplied to the pilot check valve 93d as a pilot pressure. As a result, the pilot check valve 93d operates as a check valve when the hydraulic pressure in the supply and discharge oil passage 84u is low, and operates in a communicating state when the hydraulic pressure in the supply and discharge oil passage 84u is high.

[0030] <Hydraulic system: flow of hydraulic oil> When the solenoid 60u of the solenoid valve 60 is energized and the solenoid valve 60 is switched to the open position, the discharge oil passage 80 is connected to the supply and discharge oil passage 84u via the solenoid valve 60, and the supply and discharge oil passage 90d is connected to the discharge oil passage 82 via the solenoid valve 60. As a result, the hydraulic oil discharged from the hydraulic pump 53 is supplied from the supply and discharge oil passage 84u to the open-side oil chambers 28u, 29u of both cylinders C1Rr, C1Fr via the flow dividing and collecting valve 87 and the supply and discharge oil passages 85u, 86u. Meanwhile, the hydraulic oil in the closed-side oil chambers 28d, 29d of both cylinders C1Rr, C1Fr is supplied from the supply and discharge oil passages 91d, 92d to the discharge oil passage 82 via the supply and discharge oil passage 90d.

[0031] This allows the piston rods 26b, 27b of the cylinders C1Rr, C1Fr to extend, and the left wing door 20 to open to the fully open position. The pilot check valve 93d of the supply / discharge oil passage 90d is switched to a communicating state because the hydraulic pressure in the supply / discharge oil passage 84u is high. In other words, the hydraulic oil is guided from the supply / discharge oil passage 90d to the discharge oil passage 82 through the pilot check valve 93d that operates to the communicating state.

[0032] When the solenoid 60d of the solenoid valve 60 is energized and the solenoid valve 60 is switched to the closed position, the discharge oil passage 80 is connected to the supply and discharge oil passage 90d via the solenoid valve 60, and the supply and discharge oil passage 84u is connected to the discharge oil passage 82 via the solenoid valve 60. As a result, the hydraulic oil discharged from the hydraulic pump 53 is supplied from the supply and discharge oil passage 90d through the supply and discharge oil passages 91d and 92d to the closed oil chambers 28d and 29d of both cylinders C1Rr and C1Fr. On the other hand, the hydraulic oil in the open oil chambers 28u and 29u of both cylinders C1Rr and C1Fr is supplied from the supply and discharge oil passages 85u and 86u to the discharge oil passage 82 through the flow dividing and collecting valve 87 and the supply and discharge oil passage 84u.

[0033] This allows the piston rods 26b, 27b of the cylinders C1Rr, C1Fr to be contracted, and the left wing door 20 to be closed toward the fully closed position. The pilot check valve 88u of the supply / drain oil passage 84u is switched to a communicating state because the hydraulic pressure in the supply / drain oil passage 90d is high. In other words, the hydraulic oil is guided from the supply / drain oil passage 84u to the drain oil passage 82 through the pilot check valve 88u that operates to the communicating state.

[0034] When the solenoid valve 60 is switched to the stop position, the discharge oil passage 80 is blocked by the solenoid valve 60, and the supply and discharge oil passages 90d, 84u are connected to the discharge oil passage 82 via the solenoid valve 60. As a result, the hydraulic oil in the opening oil chamber 28u and the closing oil chamber 28d of the rear cylinder C1Rr is held by the pilot check valve 88u functioning as a check valve. Similarly, the hydraulic oil in the opening oil chamber 29u and the closing oil chamber 29d of the front cylinder C1Fr is held by the pilot check valve 93d functioning as a check valve. In other words, when the solenoid valve 60 is switched to the stop position, the left wing door 20 is held at any stop position.

[0035] <Flow distribution valve> 5A, 5B, 6A, and 6B are diagrams showing an example of the structure and operating state of the flow dividing and collecting valve 87. As shown in FIG. 5A, the flow dividing and collecting valve 87 has a housing 100 in which supply and discharge ports 87A, 87B, and 87C are formed, a spool 101 movably housed in the housing 100, and a spool 102 movably housed in the housing 100. An orifice 101a and a port 101b are formed in the spool 101, and an orifice 102a and a port 102b are formed in the spool 102. In addition, a spring member 104 is assembled between the housing 100 and the spool 101, and a spring member 105 is assembled between the housing 100 and the spool 102. In addition, a spring member 103 is assembled between the spool 101 and the spool 102.

[0036] 5A, when hydraulic oil flows from supply / discharge port 87A to supply / discharge ports 87B and 87C, the hydraulic oil flows between spool 101 and spool 102, so that spool 101 and spool 102 are separated from each other. The hydraulic oil flowing in from supply / discharge port 87A flows through orifice 101a and port 101b of spool 101 to supply / discharge port 87B, and also flows through orifice 102a and port 102b of spool 102 to supply / discharge port 87C. At this time, flow dividing and collecting valve 87 keeps the amount of hydraulic oil divided and flowing to supply / discharge ports 87B and 87C approximately constant.

[0037] For example, as shown in FIG. 5B, when the amount of hydraulic oil flowing to the supply / discharge port 87B is restricted by an increase in flow resistance, the hydraulic oil pressure at the supply / discharge port 87B becomes higher than the hydraulic oil pressure at the supply / discharge port 87C. Then, a thrust due to the hydraulic difference acts on the spools 101 and 102, so that the spools 101 and 102 move in the direction of the arrow x1 to reduce the opening area between the supply / discharge port 87C and the port 102b. This makes it possible to throttle the amount of hydraulic oil flowing into the supply / discharge port 87C, so that the amount of hydraulic oil diverted to the two supply / discharge ports 87B and 87C can be made almost constant. In other words, when the piston rods 26b and 27b of the cylinders C1Rr and C1Fr are extended, the moving speeds of the piston rods 26b and 27b can be synchronized.

[0038] As shown in FIG. 6A, when hydraulic oil flows from the supply / discharge ports 87B and 87C to the supply / discharge port 87A, the hydraulic oil flows between the housing 100 and the spool 101, and the hydraulic oil flows between the housing 100 and the spool 102, so that the spools 101 and 102 approach each other. The hydraulic oil flowing in from the supply / discharge port 87B flows into the supply / discharge port 87A through the port 101b and the orifice 101a of the spool 101. The hydraulic oil flowing in from the supply / discharge port 87C flows into the supply / discharge port 87A through the port 102b and the orifice 102a of the spool 102. At this time, the flow dividing and collecting valve 87 keeps the amount of hydraulic oil flowing in from each of the supply / discharge ports 87B and 87C almost constant.

[0039] For example, as shown in Fig. 6B, when the hydraulic pressure at the supply / discharge port 87C becomes higher than the hydraulic pressure at the supply / discharge port 87B, and the amount of hydraulic oil flowing into the supply / discharge port 87C increases, the spools 101, 102 move in the direction of the arrow x2 due to the thrust caused by the hydraulic pressure difference. This movement of the spools 101, 102 reduces the opening area between the supply / discharge port 87C and the port 102b, so that the amount of hydraulic oil flowing into the supply / discharge port 87C can be reduced, and the amount of hydraulic oil flowing from the two supply / discharge ports 87B, 87C can be made substantially constant. In other words, when the piston rods 26b, 27b of the cylinders C1Rr, C1Fr are retracted, the moving speeds of the piston rods 26b, 27b can be synchronized.

[0040] <Electrical system: configuration> Hereinafter, there will be described an energization system 110 including an electric circuit for controlling the energized state of the electric motor 52 and the solenoid valves 60, 70. Fig. 7 is a diagram showing an example of the energization system 110 provided in the wing opening / closing device 50.

[0041] As shown in FIG. 7, the wing opening / closing device 50 has an energization system 110 that controls the energization state of the electric motor 52 and the solenoid valves 60, 70. The energization system 110 has a main switch 111, an open button switch B1u, a close button switch B1d, an open button switch B2u, and a close button switch B2d that are manually operated by an operator. The main switch 111 is a switch that is operated when starting and stopping the wing opening / closing device 50. The open button switch B1u is a switch that is pressed when opening the left wing door 20, and the close button switch B1d is a switch that is pressed when closing the left wing door 20. The open button switch B2u is a switch that is pressed when opening the right wing door 30, and the close button switch B2d is a switch that is pressed when closing the right wing door 30.

[0042] The energization system 110 has a power supply line 113 constituting a power supply circuit 112. A battery 114 is connected to the power supply line 113, and a main switch 111 is provided on the power supply line 113. A solenoid 60u of the solenoid valve 60 is connected to the power supply line 113 via an open button switch B1u, and a solenoid 60d of the solenoid valve 60 is connected to the power supply line 113 via a close button switch B1d. A solenoid 70u of the solenoid valve 70 is connected to the power supply line 113 via an open button switch B2u, and a solenoid 70d of the solenoid valve 70 is connected to the power supply line 113 via a close button switch B2d.

[0043] The electric motor 52 is connected to the power supply line 113 via a magnet switch 115. The coil 115a of the magnet switch 115 is connected to the power supply line 113 via a motor relay 116. The coil 116a of the motor relay 116 is connected to a current supply line 117 that is energized when the open button switch B1u or the like is operated. When the motor relay 116 is switched to the ON state with the current supply to the coil 116a, the power supply line 113 is connected to the coil 115a via the motor relay 116, and the magnet switch 115 is switched to the ON state with the current supply to the coil 115a. In this way, when the magnet switch 115 is switched to the ON state, the power supply line 113 is connected to the electric motor 52 via the magnet switch 115, and the electric motor 52 connected to the hydraulic pump 53 is rotated. The current carrying line 117 connected to the coil 116a of the motor relay 116 is energized when the open button switch B1u, the close button switch B1d, the open button switch B2u or the close button switch B2d is pressed.

[0044] <Electrical system and hydraulic system: opening and closing operation of wing door> The opening and closing operations of the left wing door 20 by operating the button switches B1u and B1d are the same as those of the right wing door 30 by operating the button switches B2u and B2d. Therefore, in the following description, the opening and closing operations of the left wing door 20 will be described, and the description of the opening and closing operations of the right wing door 30 will be omitted.

[0045] When the main switch 111 is turned ON and an operator presses the open button switch B1u, the electric motor 52 drives the hydraulic pump 53, and the solenoid valve 60 is switched to the open position by energizing the solenoid 60u. This allows the piston rods 26b, 27b of the left cylinders C1Rr, C1Fr to extend, and the left wing door 20 to open to the fully open position. When the open button switch B1u is released, the solenoid valve 60 is switched to the stop position, and the left wing door 20 stops on the spot.

[0046] When the main switch 111 is turned ON and an operator presses the close button switch B1d, the electric motor 52 drives the hydraulic pump 53, and the solenoid valve 60 is switched to the close position by energizing the solenoid 60d. This allows the piston rods 26b, 27b of the left cylinders C1Rr, C1Fr to be contracted, and the left wing door 20 can be closed toward the fully closed position. When the close button switch B1d is released, the solenoid valve 60 is switched to the stop position, and the left wing door 20 stops on the spot.

[0047] 4, the discharge oil passage 80 and the discharge oil passage 82 are connected via a relief valve 118. As a result, when the hydraulic pressure in the discharge oil passage 80 exceeds a predetermined value, the hydraulic oil is guided from the discharge oil passage 80 to the discharge oil passage 82 via the relief valve 118, and an excessive increase in the hydraulic pressure in the discharge oil passage 80 is avoided. In other words, even when the wing doors 20, 30 move to the fully open position or the fully closed position and the hydraulic pressure in the cylinders C1Rr, C1Fr, C2Rr, C2Fr increases, the relief valve 118 opens and the hydraulic system 51 is appropriately protected.

[0048] <Latching relay> However, when the lashing belt 40 is attached to the box-type loading platform 10, if an operator presses the open button switch B1u to open the wing door 20, there is a risk of deforming the wing door 20. In other words, the lashing belt 40 is often attached to the rear of the loading platform, and at this time, the rear end 24 of the wing door 20 is restrained by the lashing belt 40. In this state, if the piston rod 27b of the front cylinder C1Fr is extended, the wing door 20 is twisted by the front cylinder C1Fr, and there is a risk of deforming the wing door 20. Therefore, the wing opening and closing device 50 of the present disclosure has latching relays 120, 130 for protecting the wing doors 20, 30.

[0049] 7, the current supply system 110 of the wing opening / closing device 50 has a latching relay (relay) 120 for protecting the left wing door 20. The latching relay 120 provided on the power supply line 113 has a movable contact 121 that is movable between a connection position for connecting the power supply line 113 and a disconnection position for disconnecting the power supply line 113. The latching relay 120 also has a set coil 122 that moves the movable contact 121 to the connection position, and a reset coil (excitation coil) 123 that moves the movable contact 121 to the disconnection position.

[0050] By energizing the set coil 122, the latching relay 120 is switched to a connected state in which the power line 113 is connected, and by energizing the reset coil 123, the latching relay 120 is switched to a disconnected state in which the power line 113 is disconnected. In addition, a current supply line 124 of the set coil 122 is connected to the power line 113 via a reset button switch 125. In addition, a current supply line 126 of the reset coil 123 is connected to the power line 113 via pressure switches S1Rr and S1Fr that are connected in series with each other.

[0051] The pressure switch S1Rr has a movable contact (contact, first contact) 127 that can be moved between a connection position for connecting the current line 126 and a disconnection position for disconnecting the current line 126. When the hydraulic pressure in the supply / discharge oil passage 85u is equal to or lower than a first threshold value (threshold value) P1, the pressure switch S1Rr operates in an OFF state to open the movable contact 127. On the other hand, when the hydraulic pressure in the supply / discharge oil passage 85u exceeds the first threshold value P1, the pressure switch S1Rr operates in an ON state to close the movable contact 127. In other words, when the hydraulic pressure in the supply / discharge oil passage 85u exceeds the first threshold value P1, the pressure switch S1Rr is switched from an OFF state to open the movable contact 127 to an ON state to close the movable contact 127. The first threshold value P1 is set to, for example, "11 MPa."

[0052] The pressure switch S1Fr has a movable contact (second contact) 128 that can be moved between a connection position for connecting the current line 126 and a disconnection position for disconnecting the current line 126. The pressure switch S1Fr operates to an ON state in which the movable contact 128 is closed when the hydraulic pressure in the supply / discharge oil passage 86u is equal to or lower than a second threshold P2 that is lower than the first threshold P1. That is, the pressure switch S1Fr operates to an ON state in which the hydraulic pressure in the supply / discharge oil passage 86u is lower than the second threshold P2. On the other hand, the pressure switch S1Fr operates to an OFF state in which the movable contact 127 is opened when the hydraulic pressure in the supply / discharge oil passage 86u exceeds the second threshold P2. That is, when the hydraulic pressure in the supply / discharge oil passage 86u exceeds the second threshold P2, the pressure switch S1Fr is switched from an ON state in which the movable contact 127 is closed to an OFF state in which the movable contact 127 is opened. The second threshold P2 is set to, for example, "9 MPa."

[0053] Similarly, the current supply system 110 of the wing opening / closing device 50 has a latching relay (relay) 130 for protecting the right wing door 30. Also, as shown in Fig. 4, a supply / drain oil passage (first oil passage) 85u is connected to the opening side oil chamber (first opening side oil chamber) 28u of the rear cylinder C2Rr, and a pressure switch (hydraulic switch, first hydraulic switch) S2Rr is connected to this supply / drain oil passage 85u. Furthermore, a supply / drain oil passage (second oil passage) 86u is connected to the opening side oil chamber (second opening side oil chamber) 29u of the front cylinder C2Fr, and a pressure switch (second hydraulic switch) S2Fr is connected to this supply / drain oil passage 86u.

[0054] The latching relay 130 and the pressure switches S2Rr, S2Fr function in the same manner as the latching relay 120 and the pressure switches S1Rr, S1Fr described above. That is, the movable contact 131 corresponds to the movable contact 121, the set coil 132 corresponds to the set coil 122, and the reset coil (excitation coil) 133 corresponds to the reset coil 123. Also, the energizing line 134 corresponds to the energizing line 124, the return button switch 135 corresponds to the return button switch 125, and the energizing line 136 corresponds to the energizing line 126. Also, the movable contact (contact, first contact) 137 corresponds to the movable contact 127, and the movable contact (second contact) 138 corresponds to the movable contact 128.

[0055] <Latching relay: operation> Next, the operation of the latching relays 120, 130 will be described. The operation of the latching relay 120 when the left wing door 20 is opened and the operation of the latching relay 130 when the right wing door 30 is opened are the same. For this reason, in the following explanation, the operation of the latching relay 120 when the left wing door 20 is opened will be explained, and the explanation of the operation of the latching relay 130 when the right wing door 30 is opened will be omitted.

[0056] (normally open) Fig. 8 is a diagram showing the operation state of the current supply system 110 during normal opening. Fig. 9A is a diagram showing the operation state of the cylinders C1Rr, C1Fr during normal opening, and Fig. 9B is a diagram showing the increase state of the hydraulic pressure during normal opening. Note that normal opening refers to a state in which the lashing belt 40 is detached from the wing door 20 and the wing door 20 is not subjected to a high load due to snow accumulation or the like, and the open button switch B1u is pressed to open the wing door 20.

[0057] 8, when the open button switch B1u is pressed by an operator during normal opening, the motor relay 116 and the magnet switch 115 are switched to the ON state, and the hydraulic pump 53 is rotated and driven by the electric motor 52. When the open button switch B1u is pressed by an operator, the solenoid valve 60 is switched to the open position by energizing the solenoid 60u. As a result, hydraulic oil is supplied to the open-side oil chambers 28u, 29u of the cylinders C1Rr, C1Fr, and hydraulic oil is discharged from the close-side oil chambers 28d, 29d of the cylinders C1Rr, C1Fr.

[0058] As shown in Fig. 9A, during normal opening, the piston rods 26b, 27b of the cylinders C1Rr, C1Fr extend in synchronization with each other. Also, during normal opening, the resistance, i.e., the load, when opening the wing door 20 is small, so that the hydraulic pressure of the open-side oil chambers 28u, 29u of the cylinders C1Rr, C1Fr, i.e., the hydraulic pressure of the supply / discharge oil passages 85u, 86u acting on the pressure switches S1Rr, S1Fr, remains within a range not exceeding the second threshold value P2, as shown in Fig. 9B. In other words, during normal opening, the pressure switch S1Fr is in the ON state, and the pressure switch S1Rr is in the OFF state.

[0059] 8, during normal opening, the current carrying line 126 of the reset coil 123 is disconnected by the pressure switch S1Rr, and therefore the latching relay 120 is maintained in a connected state in which the power supply line 113 is connected. In other words, the latching relay 120 is maintained in a connected state in which current is carried to the electric motor 52 and the solenoid 60u, and therefore the electric motor 52 and the solenoid 60u can be operated to open the wing door 20.

[0060] (Release restraint) Fig. 10 is a diagram showing the operation of the current supply system 110 when the restraint is released. Fig. 11A is a diagram showing the operation of the cylinders C1Rr, C1Fr when the restraint is released, and Fig. 11B is a diagram showing the increase in hydraulic pressure when the restraint is released. Note that the restraint release state refers to a state in which the open button switch B1u is pressed to open the wing door 20 with the lashing belt 40 attached to the wing doors 20, 30.

[0061] 10, when the open button switch B1u is pressed by an operator during restraint release, the motor relay 116 and the magnet switch 115 are switched to the ON state, and the hydraulic pump 53 is rotated and driven by the electric motor 52. When the open button switch B1u is pressed by an operator, the solenoid valve 60 is switched to the open position by energizing the solenoid 60u. As a result, hydraulic oil is supplied to the open-side oil chambers 28u, 29u of the cylinders C1Rr, C1Fr, and hydraulic oil is discharged from the close-side oil chambers 28d, 29d of the cylinders C1Rr, C1Fr.

[0062] As shown in Fig. 11A, when the restraint is released, the rear end portion 24 of the wing door 20 is restrained by the lashing belt 40, so that a large load acts on the piston rod 26b of the rear cylinder C1Rr. When the movement of the piston rod 26b is restricted by the lashing belt 40, the hydraulic pressure of the supply / discharge oil passage 85u increases compared to the hydraulic pressure of the supply / discharge oil passage 86u, so that the spools 101, 102 of the flow dividing and collecting valve 87 move in the direction of the arrow x1 as shown in Fig. 5B.

[0063] Such operation of the flow dividing and collecting valve 87 limits the amount of hydraulic oil flowing into the rear cylinder C1Rr, so that the hydraulic oil pressure in the supply and discharge oil passage 85u acting on the pressure switch S1Rr further increases, and as shown in Fig. 11B, the hydraulic oil pressure in the supply and discharge oil passage 85u exceeds the first threshold value P1. Note that, because the hydraulic oil flowing into the front cylinder C1Fr is throttled by the flow dividing and collecting valve 87, the hydraulic oil pressure in the supply and discharge oil passage 86u acting on the pressure switch S1Fr remains within a range not exceeding the second threshold value P2.

[0064] That is, during restraint release, the pressure switch S1Fr maintains its ON state, and when the hydraulic pressure in the supply / discharge oil passage 85u exceeds the first threshold value P1, the pressure switch S1Rr is switched from the OFF state to the ON state. Then, as shown in Fig. 10, when the pressure switch S1Rr is switched from the OFF state to the ON state, the current line 126 of the reset coil 123 is connected by the pressure switches S1Rr and S1Fr, as indicated by the arrow α, and the latching relay 120 is switched to a disconnected state in which the power line 113 is disconnected. As a result, current to the electric motor 52 and the solenoid 60u is cut off, and the wing door 20 can be stopped on the spot.

[0065] That is, when the operation of the rear cylinder C1Rr is restricted by the lashing belt 40, the hydraulic pressure of the supply / discharge oil passage 85u acting on the pressure switch S1Rr is rapidly increased in accordance with the operation of the flow dividing and collecting valve 87. This allows the latching relay 120 to be switched from a connected state to a disconnected state, and the power supply to the electric motor 52 is cut off to stop the wing door 20. In this way, since the hydraulic pressure acting on the pressure switch S1Rr can be quickly raised by the flow dividing and collecting valve 87, the front cylinder C1Fr can be stopped early, and deformation of the wing door 20 can be suppressed to protect the wing door 20.

[0066] Even if the power line 113 is disconnected by the latching relay 120, the latching relay 120 can be restored to the connected state by pressing the reset button switch 125 after removing the lashing belt 40. In other words, by pressing the reset button switch 125, it is possible to energize the set coil 122 and move the movable contact 121 to the connected position, and the latching relay 120 can be restored to the connected state.

[0067] (High load release) Fig. 12 is a diagram showing the operation state of the current supply system 110 when a high load is released. Fig. 13A is a diagram showing the operation state of the cylinders C1Rr, C1Fr when a high load is released, and Fig. 13B is a diagram showing the increase in the hydraulic pressure when a high load is released. Note that a high load release refers to a state in which the lashing belt 40 is removed from the wing door 20, but the wing door 20 is under a high load due to snow accumulation or the like, and the open button switch B1u is pressed to open the wing door 20.

[0068] 12, when the open button switch B1u is pressed by an operator during high load release, the motor relay 116 and the magnet switch 115 are switched to the ON state, and the hydraulic pump 53 is rotated and driven by the electric motor 52. When the open button switch B1u is pressed by an operator, the solenoid valve 60 is switched to the open position by energizing the solenoid 60u. As a result, hydraulic oil is supplied to the open-side oil chambers 28u, 29u of the cylinders C1Rr, C1Fr, and hydraulic oil is discharged from the close-side oil chambers 28d, 29d of the cylinders C1Rr, C1Fr.

[0069] As shown in Fig. 13A, during high load release, the piston rods 26b, 27b of the cylinders C1Rr, C1Fr extend in synchronization with each other. Also, during high load release, the resistance, i.e., the load, when opening the wing door 20 is large, so that the hydraulic pressures of the open-side oil chambers 28u, 29u of the cylinders C1Rr, C1Fr, i.e., the hydraulic pressures of the supply and discharge oil passages 85u, 86u acting on the pressure switches S1Rr, S1Fr, are both expected to exceed the second threshold value P2, as shown in Fig. 13B.

[0070] That is, during high load release, the pressure switch S1Rr maintains its OFF state, and the pressure switch S1Fr is switched from the ON state to the OFF state at the timing when the hydraulic pressure in the supply / discharge oil passage 86u exceeds the second threshold value P2. Then, as shown in Fig. 12, when the pressure switch S1Fr switches from the ON state to the OFF state, the current supply line 126 of the reset coil 123 is cut off by the pressure switch S1Fr. As a result, as shown by the symbol β, even if the pressure switch S1Rr is later switched from the OFF state to the ON state, the current supply to the reset coil 123 can be maintained cut off, and the wing opening / closing device 50 can function properly.

[0071] That is, since the load when opening the wing door 20 is large, even if the hydraulic pressure in the supply / discharge oil passages 85u, 86u later exceeds the first threshold value P1 and the pressure switch S1Rr is switched from the OFF state to the ON state, the latching relay 120 can be maintained in the connected state. In this way, when the hydraulic pressures in the supply / discharge oil passages 85u, 86u both rise, by switching the pressure switch S1Fr to the OFF state first, the wing door 20 can be kept open by the wing opening / closing device 50 even if the pressure switch S1Rr is later switched to the ON state.

[0072] <Second embodiment> In the above description, the pressure switches S1Fr, S2Fr are provided in the wing opening / closing device 50, but the present invention is not limited to this, and the pressure switches S1Fr, S2Fr may be omitted from the wing opening / closing device 50. Fig. 14 is a diagram showing an energization system 141 of a wing opening / closing device 140 according to another embodiment. In Fig. 14, the same members and parts as those shown in Fig. 7 are denoted by the same reference numerals, and their description will be omitted.

[0073] As shown in Fig. 14, the energization system 141 of the wing opening / closing device 140 has a latching relay 120 for protecting the left wing door 20. Moreover, the energization line 126 of the reset coil 123 included in the latching relay 120 is connected to the power supply line 113 via a pressure switch S1Rr. Similarly, the energization system 141 of the wing opening / closing device 140 has a latching relay 130 for protecting the right wing door 30. Moreover, the energization line 136 of the reset coil 133 included in the latching relay 130 is connected to the power supply line 113 via a pressure switch S2Rr.

[0074] In this way, even if the pressure switches S1Fr, S2Fr are not provided, when the rear end 24 of the wing door 20 is restrained by the lashing belt 40 and a large load acts on the piston rod 26b of the rear cylinder C1Rr, the spools 101, 102 of the flow distribution and collection valve 87 move in the direction of the arrow x1 as shown in Fig. 5B. Due to the operation of this flow distribution and collection valve 87, the hydraulic pressure of the supply and discharge oil passage 85u acting on the pressure switch S1Rr rises quickly, and the hydraulic pressure of the supply and discharge oil passage 85u exceeds the first threshold value P1.

[0075] That is, during restraint release, the pressure switch S1Rr is switched from the OFF state to the ON state at the timing when the hydraulic pressure of the supply / discharge oil passage 85u exceeds the first threshold value P1. Then, when the pressure switch S1Rr is switched from the OFF state to the ON state, as shown by the arrow α, the current carrying line 126 of the reset coil 123 is connected by the pressure switch S1Rr, so that the latching relay 120 is switched to a disconnected state in which the power line 113 is disconnected. As a result, the current carrying to the electric motor 52 and the solenoid 60u is cut off, so that the wing door 20 can be stopped on the spot and the wing door 20 can be protected.

[0076] <Third embodiment> In the example shown in Fig. 7, the wing opening / closing device 50 is provided with latching relays 120, 130, but the present invention is not limited to this, and a relay equipped with a self-holding circuit may be used. Fig. 15 is a diagram showing a current-carrying system 151 of a wing opening / closing device 150 according to another embodiment. In Fig. 15, the same members and parts as those shown in Fig. 7 are denoted by the same reference numerals, and the description thereof will be omitted.

[0077] As shown in FIG. 15, the energization system 151 of the wing opening / closing device 150 has a relay 152 equipped with a self-holding circuit to protect the left wing door 20. The relay 152 provided on the power supply line 113 has a movable contact 153 that can move between a connection position for connecting the power supply line 113 and a disconnection position for disconnecting the power supply line 113. The relay 152 also has an excitation coil 154 that moves the movable contact 121. When the energization of the excitation coil 154 is cut off, the movable contact 153 is connected to a terminal 153a and moves to a connection position for connecting the power supply line 113. On the other hand, when the energization of the excitation coil 154 is performed, the movable contact 153 is connected to a terminal 153b and moves to a disconnection position for disconnecting the power supply line 113. Also, the energization line 155 of the excitation coil 154 is connected to the power supply line 113 via a diode 157 and pressure switches S1Rr and S1Fr that are connected in series with each other. Furthermore, the current carrying line 155 of the exciting coil 154 is connected to the terminal 153 b via a reset button switch 156 .

[0078] Similarly, the current supply system 151 of the wing opening / closing device 150 has a relay 162 equipped with a self-holding circuit to protect the right wing door 20. This relay 162 functions in the same manner as the above-mentioned relay 152. That is, the movable contact 163 corresponds to the movable contact 153, the exciting coil 164 corresponds to the exciting coil 154, the terminal 163a corresponds to the terminal 153a, and the terminal 163b corresponds to the terminal 153b. In addition, the current supply line 165 corresponds to the current supply line 155, the reset button switch 166 corresponds to the reset button switch 156, and the diode 167 corresponds to the diode 157.

[0079] In this way, even when the relays 152, 162 equipped with the self-holding circuit are used, when the rear end portion 24 of the wing door 20 is restrained by the lashing belt 40 and a large load acts on the piston rod 26b of the rear cylinder C1Rr, the spools 101, 102 of the flow distribution and collection valve 87 move in the direction of the arrow x1 as shown in Fig. 5B. This operation of the flow distribution and collection valve 87 causes the hydraulic pressure of the supply and discharge oil passage 85u acting on the pressure switch S1Rr to rise quickly, and the hydraulic pressure of the supply and discharge oil passage 85u exceeds the first threshold value P1.

[0080] That is, during the restraint release, the pressure switch S1Fr maintains its ON state, and when the hydraulic pressure in the supply / discharge oil passage 85u exceeds the first threshold value P1, the pressure switch S1Rr is switched from the OFF state to the ON state. Then, as shown in Fig. 15, when the pressure switch S1Rr is switched from the OFF state to the ON state, the current supply line 155 of the exciting coil 154 is connected by the pressure switch S1Rr, as shown by the arrow α, and the relay 152 is switched to a disconnected state in which the power supply line 113 is disconnected. As a result, the current supply to the electric motor 52 and the solenoid 60u is cut off, so that the wing door 20 can be stopped on the spot and the wing door 20 can be protected.

[0081] When the relay 152 is switched to the disconnected state, the exciting coil 154 is energized via the movable contact 153 and the reset button switch 156, so that the relay 152 is maintained in the disconnected state. Even if the power line 113 is disconnected by the relay 152, the relay 152 can be restored to the connected state by pressing the reset button switch 156 after removing the lashing belt 40. Also, in the wing opening / closing device 150, the pressure switches S1Fr and S2Fr may be omitted from the energization system 151, as in the circuit structure shown in FIG.

[0082] <Fourth and Fifth Embodiments> In the above description, a box-type loading platform 10 on which the wing opening / closing devices 50, 140, 150 are used is exemplified by a box-type loading platform integrally provided on a truck, which is a vehicle 11, but the present invention is not limited to this and may be other box-type loading platforms. Here, Fig. 16A and Fig. 16B are diagrams showing box-type loading platforms 171, 180 according to other embodiments.

[0083] As shown in FIG. 16A, the box-type loading platform on which the wing opening / closing device 50, 140, 150 is used may be a box-type loading platform 171 that is integrally provided on a semi-trailer (vehicle) 170 towed by a tractor. This box-type loading platform 171 is provided with a wing door 172. As shown in FIG. 16B, the box-type loading platform on which the wing opening / closing device 50, 140 is used may be a free-standing box-type loading platform 180 that is detachably mounted on a flatbed trailer (vehicle). This box-type loading platform 180 is provided with a wing door 181. Furthermore, the box-type loading platform on which the wing opening / closing device 50, 140, 150 is used may be a container-type box-type loading platform that is detachably mounted on a vehicle such as a trailer or a freight train.

[0084] The present disclosure is not limited to the above-described embodiment, and may be modified in various ways without departing from the spirit of the present disclosure. For example, in the above description, when the operation of the rear cylinder C1Rr is restricted by the lashing belt 40, the flow dividing and collecting valve 87 is used to restrict the amount of hydraulic oil flowing into the front cylinder C1Fr. However, the present disclosure is not limited to this, and the flow dividing and collecting valve 87 may be used to block the hydraulic oil flowing toward the front cylinder C1Fr. In addition, the structure of the flow dividing and collecting valve 87 is not limited to the structure shown in FIG. 5A, and may be another structure. Furthermore, in the above description, the flow dividing and collecting valve 87, that is, a valve having the functions of both a flow dividing valve and a flow collecting valve, is used, but the present disclosure is not limited to this, and a flow dividing valve may be provided in the hydraulic system 51 instead of the flow dividing and collecting valve 87.

[0085] In the above description, when the operation of the rear cylinder C1Rr is restricted and the hydraulic pressure of the supply / discharge oil passage 85u exceeds the first threshold value P1, the latching relays 120, 152 are switched to the disconnected state using the pressure switch S1Rr, but this is not limited to this. For example, a pressure sensor may detect a situation in which the hydraulic pressure of the supply / discharge oil passage 85u exceeds the first threshold value P1, and an electronic control unit that receives a signal from the pressure sensor may control relays such as the latching relays 120, 152 to the disconnected state. In this way, the relays such as the latching relays 120, 152 may be switched to the disconnected state without using the pressure switch S1Rr. In addition, in the illustrated example, the latching relays 120, 130 or the relays 152, 162 are provided to protect the left and right wing doors 20, 30, but this is not limited to this. For example, one of the latching relays 120, 130 may be omitted from the wing opening and closing devices 50, 140, and one of the relays 152, 162 may be omitted from the wing opening and closing device 150.

[0086] In the above description, the latching relays 120, 152 are switched to the disconnected state when the operation of the rear cylinder C1Rr is restricted, but this is not limited thereto, and the latching relays 120, 152 may be switched to the disconnected state when the operation of the front cylinder C1Fr is restricted. In addition, in the above description, a situation in which a fixing device such as a lashing belt 40 is attached is given as a situation in which the operation of the rear cylinder C1Rr is restricted, but this is not limited thereto. For example, even if the rear end portion 24 of the wing door 20 is in contact with an obstacle such as a building, this contact situation can be quickly detected by the pressure switch S1Rr, so that the latching relays 120, 152 can be switched to the disconnected state to protect the wing door 20. [Explanation of symbols]

[0087] 10...box-shaped loading platform, 11...vehicle, 12...loading compartment, 20...wing door, 24...rear end (first end), 25...front end (second end), 28u...open oil chamber (first open oil chamber), 28d...closed oil chamber (first closed oil chamber), 29u...open oil chamber (second open oil chamber), 29d...closed oil chamber (second closed oil chamber), 30...wing door, 34...rear end (first end), 35...front end (second end), 40...lashing belt, 41...lashing rail, 50...wing opening / closing device, 51...hydraulic system, 52...electric motor motor, 53...hydraulic pump, 85u...supply and drainage oil passage (first oil passage), 86u...supply and drainage oil passage (second oil passage), 87...flow distribution valve (flow distribution valve), 87A...supply and drainage port (input port), 87B...supply and drainage port (first output port), 87C...supply and drainage port (second output port), 112...power supply circuit, 120...latching relay (relay), 123...reset coil (excitation coil), 126...current carrying line, 127...movable contact (contact, first contact), 128...movable contact (second contact), 130...latch A switching relay (relay), 133... reset coil (excitation coil), 136... current carrying line, 137... movable contact (contact, first contact), 138... movable contact (second contact), 140... wing opening / closing device, 150... wing opening / closing device, 152... relay, 154... excitation coil, 155... current carrying line, 162... relay, 164... excitation coil, 165... current carrying line, 170... semi-trailer (vehicle), 171... box-shaped loading platform, 172... wing door, 180... box-shaped loading platform, 181... wing door, P1 ...First threshold (threshold), P2...Second threshold, C1Rr...Rear cylinder (first hydraulic cylinder), C1Fr...Front cylinder (second hydraulic cylinder), C2Rr...Rear cylinder (first hydraulic cylinder), C2Fr...Front cylinder (second hydraulic cylinder), S1Rr...Pressure switch (hydraulic switch, first hydraulic switch), S1Fr...Pressure switch (second hydraulic switch), S2Rr...Pressure switch (hydraulic switch, first hydraulic switch), S2Fr...Pressure switch (second hydraulic switch)

Claims

1. A wing opening / closing device for opening and closing a wing door of a luggage compartment, a first hydraulic cylinder attached to a first end of the wing door in a longitudinal direction and including a first opening oil chamber to which hydraulic oil is supplied when the wing door is opened; a second hydraulic cylinder attached to a second end of the wing door in a longitudinal direction and including a second opening oil chamber to which hydraulic oil is supplied when the wing door is opened; a flow dividing valve including an input port connected to a discharge oil passage of a hydraulic pump, a first output port connected to the first open-side oil chamber via a first oil passage, and a second output port connected to the second open-side oil chamber via a second oil passage; a relay that is provided in a power supply circuit of an electric motor that drives the hydraulic pump and that operates between a connected state in which current is applied to the electric motor and a disconnected state in which current is cut off; having The relay operates from the connected state to the disconnected state when the hydraulic pressure in the first oil passage exceeds a threshold value under a situation in which the wing door is opened. Wing opening and closing device.

2. The wing door opening / closing device according to claim 1, a hydraulic switch that operates from an OFF state in which a contact is opened to an ON state in which the contact is closed when the hydraulic pressure in the first oil passage exceeds the threshold value, The relay includes an exciting coil that is energized when the relay operates from the connected state to the disconnected state, The contact of the hydraulic switch is provided in a current carrying line of the excitation coil. Wing opening and closing device.

3. The wing door opening / closing device according to claim 1, The relay operates from the connected state to the disconnected state when the hydraulic pressure in the first oil passage exceeds a first threshold value, which is the threshold value, and the hydraulic pressure in the second oil passage falls below a second threshold value, which is lower than the first threshold value, under a situation in which the wing door is opened. Wing opening and closing device.

4. The wing door opening / closing device according to claim 3, a first hydraulic switch that operates from an OFF state in which a first contact is opened to an ON state in which the first contact is closed when the hydraulic pressure in the first oil passage exceeds the first threshold value; a second hydraulic switch that operates from an ON state in which a second contact is closed to an OFF state in which the second contact is opened when the hydraulic pressure in the second oil passage exceeds the second threshold value; having The relay includes an exciting coil that is energized when the relay operates from the connected state to the disconnected state, The first contact and the second contact are connected in series to each other and provided on a current carrying line of the excitation coil. Wing opening and closing device.

5. The wing door opening / closing device according to claim 1, The wing door has a lashing rail. Wing opening and closing device.

6. The wing door opening / closing device according to claim 1, The wing door is provided on a box-type loading platform that is integral with the vehicle or that is detachably mounted on the vehicle, The first end is located rearward of the second end. Wing opening and closing device.

Images