Hydraulic automatic opening and closing device for vehicle door and opening and closing method

Abstract

A first output end of a two-way hydraulic pump is connected with one end of a second oil way, one end of a third oil way and one end of a first auxiliary oil way, the other end of the second oil way is connected with a left end connector of a shuttle valve, the second oil way is communicated with the third oil way, and a first hydraulic control one-way valve is installed in the third oil way; the other end of the third oil way is connected with a rodless cavity of the hydraulic cylinder, and the other end of the first auxiliary oil way is matched with one end of the second hydraulic control one-way valve. A second output end of the bidirectional hydraulic pump is connected with one end of a fourth oil way, one end of a fifth oil way and one end of a second auxiliary oil way, the other end of the fourth oil way is connected with a right end connector of the shuttle valve, the fourth oil way is communicated with the fifth oil way, a second hydraulic control one-way valve is installed in the fifth oil way, and the other end of the fifth oil way is connected with a rod cavity of the hydraulic cylinder. The other end of the second auxiliary oil way is matched with one end of the first hydraulic control one-way valve. According to the invention, the vehicle door can be automatically opened or closed.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile doors, and in particular to a hydraulic automatic door opener and closer and an opening and closing method. Background Art

[0002] With the continuous progress and development of society, people have higher demands on travel methods. The comfort of transportation will directly affect people's choice of transportation. As an important part of the car, the comfort of opening and closing car doors will directly affect the driver and passengers' experience. Therefore, improving the opening and closing comfort of car doors is of great significance.

[0003] With the continuous development of new energy vehicles, the automatic door opening system of automobiles is also constantly developing and optimizing. The electric door opener is driven by a motor plus a gear set / screw. The driving force is relatively small, and the driving force is largely affected by the motor power. For some special vehicles (such as military vehicles and engineering machinery, which require ultra-high output force), the output force of the electric door opener is difficult to meet, and then it is necessary to continuously increase the motor power to achieve a larger driving force, but this is accompanied by an increase in the size of the motor; in addition, in some extreme environments (below -40°C, the hydraulic oil has better antifreeze properties than the motor), it has a greater impact on the performance of the motor, resulting in unstable motor output, which in turn affects the product driving performance. Therefore, it is particularly important to research and develop a hydraulic drive product that can be suitable for large driving force and extreme environments.

[0004] At present, there are mainly two ways to open car doors at home and abroad. One is manual opening, which is the form of mechanical limiters used in most existing car doors. The limiter is applied to the car door, and its main function is to control the limited position of the car door and limit the maximum opening of the door to prevent the car door from opening too much, causing sudden collision between the car door and external obstacles and inconvenience for the driver to close the door in the driving position; the traditional car limiter can only achieve the holding function at a relatively limited position when opening and closing the door, and cannot achieve the holding function at any position. Especially in a narrow parking area, the current car door cannot be opened to the predetermined holding position and the holding function cannot be achieved, resulting in a small door opening angle, which is not conducive to passenger use, or a child fails to open the car door to the predetermined holding position during the process of opening the car door, and the car door cannot maintain the current position. The door is easy to fall back and cause injuries and safety hazards. Summary of the Invention

[0005] The invention provides a hydraulic automatic door opener and closer and an opening and closing method thereof, and the invention can enable the door to be opened or closed automatically.

[0006] The automatic hydraulic door opener and closer includes a motor, a bidirectional hydraulic pump, a valve block, an oil tank, and a hydraulic cylinder. The motor is connected to the bidirectional hydraulic pump, which is connected to the valve block, which is connected to the oil tank, and which is also connected to the hydraulic cylinder. The motor also includes a first hydraulically controlled one-way valve, a second hydraulically controlled one-way valve, and a shuttle valve. The valve block is provided with a first oil circuit, a second oil circuit, a third oil circuit, a first auxiliary oil circuit, a fourth oil circuit, a fifth oil circuit, and a second auxiliary oil circuit, wherein:

[0007] One end of the first oil circuit is connected to the oil tank, the other end of the first oil circuit is connected to the middle interface of the shuttle valve, the first output end of the bidirectional hydraulic pump is connected to one end of the second oil circuit, the third oil circuit, and the first auxiliary oil circuit respectively, the other end of the second oil circuit is connected to the left end interface of the shuttle valve, the second oil circuit and the third oil circuit are connected, the first hydraulically controlled one-way valve is installed in the third oil circuit, the other end of the third oil circuit is connected to the rodless chamber of the hydraulic cylinder, and the other end of the first auxiliary oil circuit cooperates with the control port of the second hydraulically controlled one-way valve;

[0008] The second output end of the bidirectional hydraulic pump is respectively connected to one end of the fourth oil circuit, the fifth oil circuit and the second auxiliary oil circuit. The other end of the fourth oil circuit is connected to the right end interface of the shuttle valve. The fourth oil circuit and the fifth oil circuit are connected. The second hydraulically controlled one-way valve is installed in the fifth oil circuit. The other end of the fifth oil circuit is connected to the rod chamber of the hydraulic cylinder. The other end of the second auxiliary oil circuit cooperates with the control port of the first hydraulically controlled one-way valve.

[0009] A method for opening and closing a vehicle door, using a hydraulic automatic door opener and closer, wherein the door opening process is as follows:

[0010] S11: The motor drives the bidirectional hydraulic pump to rotate forward. The hydraulic oil is output from the first output terminal of the bidirectional hydraulic pump and flows into the second oil circuit, the third oil circuit, and the first auxiliary oil circuit respectively.

[0011] S12, the hydraulic oil flowing into the second oil circuit enters the left side of the shuttle valve through the left end interface of the shuttle valve. The valve core of the shuttle valve moves to the right under the action of the hydraulic oil, so that the left side of the shuttle valve is in a closed state and the right side is in an open state; the hydraulic oil flowing into the third oil circuit causes the first hydraulic-controlled one-way valve to open forward and then enters the rodless chamber of the hydraulic cylinder. The hydraulic oil pushes the piston in the hydraulic cylinder to move right, and the piston rod extends to drive the car door to open; the hydraulic oil flowing into the first auxiliary oil circuit causes the second hydraulic-controlled one-way valve to conduct in reverse. When the piston in the hydraulic cylinder moves to the right, the hydraulic oil in the rod chamber of the hydraulic cylinder flows through the fifth oil circuit and the second hydraulic-controlled one-way valve, and then returns to the oil suction side of the two-way hydraulic pump and is sucked by the two-way hydraulic pump. At the same time, the hydraulic oil in the oil tank enters the shuttle valve through the first oil circuit, passes through the right end interface of the shuttle valve, and then flows from the fourth oil circuit to the oil suction side of the two-way hydraulic pump;

[0012] The closing process is:

[0013] S21: The motor drives the bidirectional hydraulic pump to reverse, and the hydraulic oil is output from the second output terminal of the bidirectional hydraulic pump and flows into the fourth oil circuit, the fifth oil circuit, and the second auxiliary oil circuit respectively.

[0014] S22, the hydraulic oil flowing into the fourth oil circuit enters the right side of the shuttle valve through the right end interface of the shuttle valve, and the valve core of the shuttle valve moves to the left under the action of the hydraulic oil, so that the right side of the shuttle valve is in a closed state and the left side is in an open state; the hydraulic oil flowing into the fifth oil circuit causes the second hydraulic-controlled one-way valve to open in the forward direction and then enters the rod chamber of the hydraulic cylinder, and the hydraulic oil pushes the piston in the hydraulic cylinder to move to the left, and the piston rod retracts to drive the car door to close; the hydraulic oil flowing into the second auxiliary oil circuit causes the first hydraulic-controlled one-way valve to conduct in the reverse direction. When the piston in the hydraulic cylinder moves to the left, the hydraulic oil in the rodless chamber of the hydraulic cylinder flows through the third oil circuit and the first hydraulic-controlled one-way valve, and a part of the hydraulic oil is sucked by the two-way hydraulic pump, and the other part of the hydraulic oil enters the shuttle valve through the left end interface of the shuttle valve, and then flows into the oil tank through the first oil circuit.

[0015] The present invention has the following advantages:

[0016] 1. The valve block and the hydraulic cylinder are connected by a hose, which realizes the split arrangement of the valve block and the hydraulic cylinder and facilitates flexible installation.

[0017] 2. By combining different types of valves in the valve block and designing multiple oil circuits and auxiliary oil circuits, the hydraulic system composed of these oil circuits, valves, and hydraulic pumps can realize automatic opening and closing of car doors, as well as manual opening and closing of car doors.

[0018] 3. The present invention includes an automatic door opening and closing mode and a manual door opening and closing mode. In an emergency, the door can be opened and closed normally, that is, the manual and automatic opening and closing modes do not affect each other.

[0019] 4. Compared to electric door openers, the hydraulically driven door opener of the present invention offers stepless drive, greater output driving force, and excellent frost resistance of the hydraulic oil. Furthermore, compared to electric door openers, the hydraulic system of the present invention allows manual door opening and closing even when the motor is powered off. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional view of the hydraulic automatic door opener of the present invention.

[0021] Figure 2 This is a cross-sectional structural diagram of the hydraulic automatic door opener.

[0022] Figure 3 This is the hydraulic principle diagram of the valve block and each valve.

[0023] Symbols in the accompanying drawings:

[0024] Motor 1, bidirectional hydraulic pump 2, valve block 3, first oil circuit 3a, second oil circuit 3b, third oil circuit 3c, first auxiliary oil circuit 3d, fourth oil circuit 3e, fifth oil circuit 3f, second auxiliary oil circuit 3g, sixth oil circuit 3h, third auxiliary oil circuit 3i, seventh oil circuit 3j, fourth auxiliary oil circuit 3k, eighth oil circuit 3m, ninth oil circuit 3n, oil tank 4, box body 4a, piston 4b, spring 4c, hydraulic cylinder 5, first hydraulically controlled one-way valve 6, second hydraulically controlled one-way valve 7, shuttle valve 8, first overflow valve 9, second overflow valve 10, first one-way valve 11, second one-way valve 12. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate directions or positional relationships are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0028] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0029] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0030] like Figures 1 to 3 As shown, the hydraulic automatic door opener of the present invention includes a motor 1, a bidirectional hydraulic pump 2, a valve block 3, an oil tank 4, a hydraulic cylinder 5, a first hydraulically controlled one-way valve 6, a second hydraulically controlled one-way valve 7, and a shuttle valve 8. The motor 1 is connected to the bidirectional hydraulic pump 2, the bidirectional hydraulic pump 2 is connected to the valve block 3, the valve block 3 is connected to the oil tank 4, the oil tank 4 includes a box body 4a, a piston 4b, and a spring 4c. The piston 4b is located in the box body 4a, one end of the spring 4c is connected to the piston 4b, and the other end of the spring 4c is connected to the box body 4a. The elastic force of the spring 4c makes the oil in the box body 4a have pressure, the valve block 3 is also connected to the hydraulic cylinder 5, and the valve block 3 is preferably connected to the hydraulic cylinder 5 through a hose.

[0031] Hydraulic cylinder 5 is typically connected to a load (such as a vehicle door) and achieves reciprocating linear motion under the influence of this external load. When powered, motor 1 drives bidirectional hydraulic pump 2, continuously driving hydraulic oil to flow between valve block 3 and hydraulic cylinder 5 and other components. By opening and closing various valves within valve block 3, hydraulic cylinder 5 achieves reciprocating linear motion or maintains its locking function.

[0032] The valve block 3 is provided with a first oil circuit 3a, a second oil circuit 3b, a third oil circuit 3c, a first auxiliary oil circuit 3d, a fourth oil circuit 3e, a fifth oil circuit 3f, and a second auxiliary oil circuit 3g, wherein one end of the first oil circuit 3a is connected to the oil tank 4, and the other end of the first oil circuit 3a is connected to the middle interface of the shuttle valve 8, the first output end of the bidirectional hydraulic pump 2 is respectively connected to one end of the second oil circuit 3b, the third oil circuit 3c, and the first auxiliary oil circuit 3d, the other end of the second oil circuit 3b is connected to the left end interface of the shuttle valve 8, the second oil circuit 3b and the third oil circuit 3c are connected, the first hydraulically controlled one-way valve 6 is installed in the third oil circuit 3c, the other end of the third oil circuit 3c is connected to the rodless chamber of the hydraulic cylinder 5, and the other end of the first auxiliary oil circuit 3d cooperates with the control port of the second hydraulically controlled one-way valve 7.

[0033] The second output end of the bidirectional hydraulic pump 2 is respectively connected to one end of the fourth oil circuit 3e, the fifth oil circuit 3f, and the second auxiliary oil circuit 3g. The other end of the fourth oil circuit 3e is connected to the right end interface of the shuttle valve 8. The fourth oil circuit 3e and the fifth oil circuit 3f are connected. The second hydraulically controlled one-way valve 7 is installed in the fifth oil circuit 3f. The other end of the fifth oil circuit 3f is connected to the rod chamber of the hydraulic cylinder 5. The other end of the second auxiliary oil circuit 3g cooperates with the control port of the first hydraulically controlled one-way valve 6.

[0034] The present invention also includes a first overflow valve 9. The valve block 3 is also provided with a sixth oil circuit 3h and a third auxiliary oil circuit 3i. One end of the sixth oil circuit 3h is connected to the first oil circuit 3a, and the other end of the sixth oil circuit 3h is connected to the other end of the third oil circuit 3c. The connection between the sixth oil circuit 3h and the third oil circuit 3c is located downstream of the other end of the first hydraulically controlled one-way valve 6. One end of the third auxiliary oil circuit 3i is connected to the first output end of the bidirectional hydraulic pump 2. The first overflow valve 9 is installed in the sixth oil circuit 3h, and the other end of the third auxiliary oil circuit 3i cooperates with one end of the first overflow valve 9.

[0035] The present invention also includes a second overflow valve 10. The valve block 3 is also provided with a seventh oil circuit 3j and a fourth auxiliary oil circuit 3k. One end of the seventh oil circuit 3j is connected to the first oil circuit 3a, and the other end of the seventh oil circuit 3j is connected to the other end of the fifth oil circuit 3f. The connection between the seventh oil circuit 3j and the fifth oil circuit 3f is located downstream of the other end of the second hydraulically controlled one-way valve 7. One end of the fourth auxiliary oil circuit 3k is connected to the second output end of the bidirectional hydraulic pump 2. The second overflow valve 10 is installed in the seventh oil circuit 3j, and the other end of the fourth auxiliary oil circuit 3k cooperates with one end of the second overflow valve 10.

[0036] The present invention also includes a first one-way valve 11. An eighth oil circuit 3m is also provided on the valve block 3. One end of the eighth oil circuit 3m is connected to the first oil circuit 3a, and the other end of the eighth oil circuit 3m is connected to the other end of the third oil circuit 3c. The connection between the eighth oil circuit 3m and the third oil circuit 3c is located downstream of the other end of the first hydraulically controlled one-way valve 6. The first one-way valve 11 is installed in the eighth oil circuit 3m.

[0037] The present invention also includes a second one-way valve 12. A ninth oil circuit 3n is also provided on the valve block 3. One end of the ninth oil circuit 3n is connected to the first oil circuit 3a, and the other end of the ninth oil circuit 3n is connected to the other end of the fifth oil circuit 3f. The connection between the ninth oil circuit 3n and the fifth oil circuit 3f is located downstream of the other end of the second hydraulically controlled one-way valve 7. The second one-way valve 12 is installed in the ninth oil circuit 3n.

[0038] The above-mentioned automatic hydraulic door opener and closer is used, wherein the door opening process is as follows:

[0039] S11, the motor 1 drives the bidirectional hydraulic pump 2 to rotate forward, and the hydraulic oil is output from the first output end of the bidirectional hydraulic pump 2 and flows into the second oil circuit 3b, the third oil circuit 3c, and the first auxiliary oil circuit 3d respectively.

[0040] S12, the hydraulic oil flowing into the second oil circuit 3b enters the left side of the shuttle valve 8 through the left end interface of the shuttle valve 8, and the valve core of the shuttle valve 8 moves to the right under the action of the hydraulic oil, so that the left side of the shuttle valve 8 is in a closed state and the right side is in an open state.

[0041] The hydraulic oil flowing into the third oil circuit 3c overcomes the opening force of the first hydraulically controlled one-way valve 6. The hydraulic oil opens the first hydraulically controlled one-way valve 6 in the forward direction and then enters the rodless chamber of the hydraulic cylinder 5. The hydraulic oil pushes the piston in the hydraulic cylinder 5 to move to the right, and the piston rod extends to drive the car door to open.

[0042] The hydraulic oil flowing into the first auxiliary oil circuit 3d causes the second hydraulically controlled one-way valve 7 to conduct in the reverse direction. When the piston in the hydraulic cylinder 5 moves to the right, the hydraulic oil in the rod chamber of the hydraulic cylinder 5 flows through the fifth oil circuit 3f and the second hydraulically controlled one-way valve 7, and then returns to the suction side of the two-way hydraulic pump 2 to be sucked by the two-way hydraulic pump 2. At the same time, the hydraulic oil in the oil tank 4 enters the shuttle 8 through the first oil circuit 3a, passes through the right end interface of the shuttle valve 8, and then flows from the fourth oil circuit 3e to the suction side of the two-way hydraulic pump 2.

[0043] S13, after the motor 1 drives the bidirectional hydraulic pump 2 to rotate forward, the hydraulic oil output from the first output end of the bidirectional hydraulic pump 2 also flows into the third auxiliary oil circuit 3i and then enters the first overflow valve 9, so that the opening force of the first overflow valve 9 increases, thereby increasing the output force of the hydraulic cylinder 5. If the hydraulic cylinder 5 encounters a large load during the door opening process, for example, the car door is blocked by an obstacle and cannot continue to open, at this time, the pressure in the rodless hydraulic cylinder 5 will increase. When the increased pressure exceeds the opening force of the first overflow valve 9, the first overflow valve 9 is opened, and the hydraulic oil in the rodless hydraulic cylinder 5 flows through the first overflow valve 9, the sixth oil circuit 3h, and the first oil circuit 3a and then enters the oil tank 4 to release the pressure generated when encountering a large load, thereby protecting the hydraulic system.

[0044] The closing process is:

[0045] S21: Motor 1 drives bidirectional hydraulic pump 2 to reverse direction. Hydraulic oil is output from the second output terminal of bidirectional hydraulic pump 2 and flows into fourth oil circuit 3e, fifth oil circuit 3f, and second auxiliary oil circuit 3g respectively.

[0046] S22, the hydraulic oil flowing into the fourth oil circuit 3e enters the right side of the shuttle valve 8 through the right end interface of the shuttle valve 8. The valve core of the shuttle valve 8 moves to the left under the action of the hydraulic oil, so that the right side of the shuttle valve 8 is in a closed state and the left side is in an open state; the hydraulic oil flowing into the fifth oil circuit 3f opens the second hydraulically controlled one-way valve 7 in the forward direction and then enters the rod chamber of the hydraulic cylinder 5. The hydraulic oil pushes the piston in the hydraulic cylinder 5 to move left, and the piston rod retracts to drive the car door to close; the hydraulic oil flowing into the second auxiliary oil circuit 3g reversely conducts the first hydraulically controlled one-way valve 6. When the piston in the hydraulic cylinder 5 moves to the left, the hydraulic oil in the rodless chamber of the hydraulic cylinder 5 flows through the third oil circuit 3c and the first hydraulically controlled one-way valve 6. Part of the hydraulic oil is sucked by the bidirectional hydraulic pump 2, and the other part of the hydraulic oil enters the shuttle valve 8 through the left end interface of the shuttle valve 8, and then flows into the oil tank 4 through the first oil circuit 3a.

[0047] It should be noted that since the hydraulic system in the hydraulic automatic opener is a completely sealed system, the entire hydraulic system is filled with oil. The hydraulic cylinder 5 is a single-rod, double-acting hydraulic cylinder. That is, the cross-sectional area of the rod cavity and the cross-sectional area of the rodless cavity of the hydraulic cylinder 5 are different, with the cross-sectional area of the rodless cavity being larger than the cross-sectional area of the rod cavity. Therefore, the volume of oil entering and leaving the hydraulic cylinder 5 during movement is different. Therefore, the shuttle valve 8 and the oil tank 4 are required to match the hydraulic oil inflow and outflow. The following are respectively explained:

[0048] 1. The piston rod of the hydraulic cylinder 5 extends (door opening process), and the volume of hydraulic oil entering the rodless chamber is greater than the volume of hydraulic oil flowing out of the rod chamber. Therefore, when the hydraulic oil in the rod chamber returns to the suction side of the two-way hydraulic pump 2, it is not enough to make up for the oil inlet of the rodless chamber. Then the missing hydraulic oil needs to be replenished from the oil tank 4, so that the hydraulic oil in the oil tank 4 enters the shuttle 8 through the first oil path 3a, passes through the right end interface of the shuttle valve 8, and then flows from the fourth oil path 3e to the suction side of the two-way hydraulic pump 2.

[0049] 2. The piston rod of the hydraulic cylinder 5 retracts (door opening process). Since the volume of hydraulic oil entering the rod chamber is smaller than the volume of hydraulic oil flowing out of the rodless chamber, only a part of the hydraulic oil flowing out of the rodless chamber can be sucked away by the two-way hydraulic pump 2. The excess hydraulic oil cannot be sucked away by the two-way hydraulic pump 2. Therefore, it can only return to the oil tank 4 through the shuttle valve 8.

[0050] S23, after the motor 1 drives the bidirectional hydraulic pump 2 to reverse, the hydraulic oil output from the second output end of the bidirectional hydraulic pump 2 also flows into the fourth auxiliary oil circuit 3k and then enters the second relief valve 10, so that the opening force of the second relief valve 10 increases, thereby increasing the force of the piston rod of the hydraulic cylinder 5 when it retracts. If the hydraulic cylinder 5 encounters a large load during the closing process, the pressure in the rod of the hydraulic cylinder 5 increases and exceeds the opening force of the second relief valve 10, so that the second relief valve 10 opens, and the hydraulic oil in the rod of the hydraulic cylinder 5 flows through the second relief valve 10, the seventh oil circuit 3j, and the first oil circuit 3a and then enters the oil tank 4 to release the pressure generated when encountering a large load.

[0051] Preferably, after the motor 1 is started, if the motor 1 is powered off, the bidirectional hydraulic pump 2 cannot output hydraulic oil. At this time, the first hydraulically controlled one-way valve 6 and the second hydraulically controlled one-way valve 7 are in a closed state. The first hydraulically controlled one-way valve 6 and the second hydraulically controlled one-way valve 7 seal the hydraulic oil in the hydraulic cylinder 5, so that the hydraulic cylinder 5 is in a held state. At this time, since the pressures in the rod chamber and the rodless chamber of the hydraulic cylinder 5 are equal, the car door is in a suspended state.

[0052] The present invention can also be operated in manual mode:

[0053] Under the action of manual operation mode, if the piston rod of the hydraulic cylinder 5 is extended outward, the oil pressure in the rod chamber of the hydraulic cylinder 5 increases, and the hydraulic oil flows into the seventh oil circuit 3j, overcoming the pressure set by the spring of the second overflow valve 10. The second overflow valve 10 opens, and the hydraulic oil returns to the oil tank 4 through the first oil circuit 3a. At the same time, in the process of the piston rod of the hydraulic cylinder 5 extending outward, the volume of the rodless chamber of the hydraulic cylinder 5 increases, and a vacuum is formed in the rodless chamber of the hydraulic cylinder 5, which is in an underpressure state. The hydraulic oil in the oil tank 4 overcomes the preset force of the first one-way valve 11 with the assistance of the spring 4c, so that the first one-way valve 11 is opened, and the hydraulic oil flows through the eighth oil circuit 3m and the first one-way valve 11 and enters the rodless chamber of the hydraulic cylinder 5, thereby causing the hydraulic cylinder 5 to form continuous movement.

[0054] The low opening pressures preset for the first and second check valves 11, 12 in the present invention facilitate smooth entry of hydraulic oil into the hydraulic cylinder 5 in manual mode, preventing the occurrence of hydraulic oil cavitation. Because a spring 4c is installed within the housing 4a, it is initially compressed, creating a backpressure condition for the hydraulic oil within the housing 4a, facilitating timely entry of the hydraulic oil into the hydraulic cylinder 5.

[0055] After the hydraulic cylinder 5 moves to a certain position under the action of an external force, the external force is removed, and the back pressure disappears. This causes the oil pressure in the rodless chamber of the hydraulic cylinder 5 to decrease, becoming insufficient to overcome the preset opening pressure of the second relief valve 10. Consequently, the second relief valve 10 switches to a closed state, and the hydraulic oil in the rodless chamber of the hydraulic cylinder 5 cannot flow into the oil tank 4. Simultaneously, the volume of the rodless chamber of the hydraulic cylinder 5 remains unchanged, and underpressure ceases to occur. The pressure gradually increases, causing the first check valve 11 to switch to a closed state, halting the movement of the piston and piston rod of the hydraulic cylinder 5. The entire hydraulic system is in a stopped state, and the piston rod remains in its current position. Therefore, when the piston rod of the hydraulic cylinder 5 drives the vehicle door to the desired position in manual operation mode, the hydraulic cylinder 5 can be placed in a suspended state after the manual operation force is removed. If the manual operation force is subsequently increased, and the oil pressure generated in manual operation is sufficient to overcome the preset opening pressure of the second relief valve 10, the second relief valve 10 opens, and the hydraulic cylinder 5 resumes operation.

[0056] Under the force of manual mode, if the piston rod of hydraulic cylinder 5 is retracted, the oil pressure in the rodless chamber of hydraulic cylinder 5 increases, and hydraulic oil flows into sixth oil passage 3h, overcoming the preset force of first relief valve 9, causing it to open. The hydraulic oil then flows through first oil passage 3a and returns to oil tank 4. Simultaneously, as the piston rod of hydraulic cylinder 5 retracts, the volume of the rod chamber of hydraulic cylinder 5 increases, creating a vacuum within the chamber, which is underpressured. With the assistance of spring 4c, the hydraulic oil in oil tank 4 overcomes the preset force of second one-way valve 12, causing it to open and allow hydraulic oil to enter the rod chamber of hydraulic cylinder 5. Under the action of a continuous external force, the hydraulic oil continuously flows between the two chambers, causing the hydraulic cylinder 5 to move continuously.

[0057] Based on the above, in electric mode, when the door is opened, hydraulic oil flows along the third auxiliary oil line 3i into the first relief valve 9, increasing the opening force of the first relief valve 9 and, in turn, the output force of the hydraulic cylinder 5. When the door is closed, hydraulic oil flows along the fourth auxiliary oil line 3k into the second relief valve 10, increasing the opening force of the second relief valve 10 and, in turn, the retraction force of the piston rod of the hydraulic cylinder 5. In manual mode, however, no hydraulic oil flows along the third auxiliary oil line 3i into the first relief valve 9, nor does any hydraulic oil flow along the fourth auxiliary oil line 3k into the second relief valve 10. Therefore, the opening force required for the first or second relief valve 9, 10 in manual mode is smaller than that required for the first or second relief valve 9, 10 in electric mode.

Claims

1. A hydraulic automatic door opener and closer, comprising a motor (1), a bidirectional hydraulic pump (2), a valve block (3), an oil tank (4), and a hydraulic cylinder (5), wherein the motor (1) is connected to the bidirectional hydraulic pump (2), the bidirectional hydraulic pump (2) is connected to the valve block (3), the valve block (3) is connected to the oil tank (4), and the valve block (3) is also connected to the hydraulic cylinder (5), and is characterized in that: It also includes a first hydraulically controlled one-way valve (6), a second hydraulically controlled one-way valve (7), and a shuttle valve (8); the valve block (3) is provided with a first oil circuit (3a), a second oil circuit (3b), a third oil circuit (3c), a first auxiliary oil circuit (3d), a fourth oil circuit (3e), a fifth oil circuit (3f), and a second auxiliary oil circuit (3g), wherein: One end of the first oil circuit (3a) is connected to the oil tank (4), the other end of the first oil circuit (3a) is connected to the middle interface of the shuttle valve (8), the first output end of the bidirectional hydraulic pump (2) is respectively connected to one end of the second oil circuit (3b), the third oil circuit (3c), and the first auxiliary oil circuit (3d), the other end of the second oil circuit (3b) is connected to the left end interface of the shuttle valve (8), the second oil circuit (3b) and the third oil circuit (3c) are connected, the first hydraulically controlled one-way valve (6) is installed in the third oil circuit (3c), the other end of the third oil circuit (3c) is connected to the rodless chamber of the hydraulic cylinder (5), and the other end of the first auxiliary oil circuit (3d) cooperates with the control port of the second hydraulically controlled one-way valve (7); The second output end of the bidirectional hydraulic pump (2) is respectively connected to one end of the fourth oil circuit (3e), the fifth oil circuit (3f), and the second auxiliary oil circuit (3g); the other end of the fourth oil circuit (3e) is connected to the right end interface of the shuttle valve (8); the fourth oil circuit (3e) and the fifth oil circuit (3f) are connected; the second hydraulically controlled one-way valve (7) is installed in the fifth oil circuit (3f); the other end of the fifth oil circuit (3f) is connected to the rod chamber of the hydraulic cylinder (5); and the other end of the second auxiliary oil circuit (3g) cooperates with the control port of the first hydraulically controlled one-way valve (6).

2. The hydraulic automatic door opener according to claim 1, characterized in that: The invention also includes a first overflow valve (9). The valve block (3) is also provided with a sixth oil circuit (3h) and a third auxiliary oil circuit (3i). One end of the sixth oil circuit (3h) is connected to the first oil circuit (3a), the other end of the sixth oil circuit (3h) is connected to the other end of the third oil circuit (3c), and one end of the third auxiliary oil circuit (3i) is connected to the first output end of the bidirectional hydraulic pump (2). The first overflow valve (9) is installed in the sixth oil circuit (3h), and the other end of the third auxiliary oil circuit (3i) cooperates with one end of the first overflow valve (9).

3. The hydraulic automatic door opener and closer according to claim 1, characterized in that: The invention also includes a second overflow valve (10). The valve block (3) is also provided with a seventh oil circuit (3j) and a fourth auxiliary oil circuit (3k). One end of the seventh oil circuit (3j) is connected to the first oil circuit (3a), the other end of the seventh oil circuit (3j) is connected to the other end of the fifth oil circuit (3f), and one end of the fourth auxiliary oil circuit (3k) is connected to the second output end of the bidirectional hydraulic pump (2). The second overflow valve (10) is installed in the seventh oil circuit (3j), and the other end of the fourth auxiliary oil circuit (3k) cooperates with one end of the second overflow valve (10).

4. The hydraulic automatic door opener and closer according to claim 1, characterized in that: It also includes a first one-way valve (11), and an eighth oil circuit (3m) is also provided on the valve block (3), one end of the eighth oil circuit (3m) is connected to the first oil circuit (3a), and the other end of the eighth oil circuit (3m) is connected to the other end of the third oil circuit (3c), and the first one-way valve (11) is installed in the eighth oil circuit (3m).

5. The hydraulic automatic door opener and closer according to claim 1, characterized in that: It also includes a second one-way valve (12). A ninth oil circuit (3n) is also provided on the valve block (3). One end of the ninth oil circuit (3n) is connected to the first oil circuit (3a), and the other end of the ninth oil circuit (3n) is connected to the other end of the fifth oil circuit (3f). The second one-way valve (12) is installed in the ninth oil circuit (3n).

6. A method for opening and closing a vehicle door, characterized in that: The vehicle door hydraulic automatic opener and closer according to any one of claims 1 to 5 is used, wherein the door opening process is: S11, the motor (1) drives the bidirectional hydraulic pump (2) to rotate forward, and the hydraulic oil is output from the first output end of the bidirectional hydraulic pump (2) and flows into the second oil circuit (3b), the third oil circuit (3c), and the first auxiliary oil circuit (3d) respectively; S12, the hydraulic oil flowing into the second oil circuit (3b) enters the left side of the shuttle valve (8) through the left end interface of the shuttle valve (8), and the valve core of the shuttle valve (8) moves to the right under the action of the hydraulic oil, so that the left side of the shuttle valve (8) is in a closed state and the right side is in an open state; the hydraulic oil flowing into the third oil circuit (3c) opens the first hydraulic control one-way valve (6) in the positive direction and then enters the rodless chamber of the hydraulic cylinder (5), and the hydraulic oil pushes the piston in the hydraulic cylinder (5) to move to the right, and the piston rod extends to drive the car door to open; the hydraulic oil flowing into the first auxiliary oil circuit (3c) The hydraulic oil in the circuit (3d) causes the second hydraulically controlled one-way valve (7) to conduct in the reverse direction. When the piston in the hydraulic cylinder (5) moves to the right, the hydraulic oil in the rod chamber of the hydraulic cylinder (5) flows through the fifth oil circuit (3f) and the second hydraulically controlled one-way valve (7), and then returns to the oil suction side of the bidirectional hydraulic pump (2) to be sucked by the bidirectional hydraulic pump (2). At the same time, the hydraulic oil in the oil tank (4) enters the shuttle valve (8) through the first oil circuit (3a), passes through the right end interface of the shuttle valve (8), and then flows from the fourth oil circuit (3e) to the oil suction side of the bidirectional hydraulic pump (2). The closing process is: S21, the motor (1) drives the bidirectional hydraulic pump (2) to reverse, and the hydraulic oil is output from the second output end of the bidirectional hydraulic pump (2) and flows into the fourth oil circuit (3e), the fifth oil circuit (3f), and the second auxiliary oil circuit (3g) respectively; S22, the hydraulic oil flowing into the fourth oil circuit (3e) enters the right side of the shuttle valve (8) through the right end interface of the shuttle valve (8), and the valve core of the shuttle valve (8) moves to the left under the action of the hydraulic oil, so that the right side of the shuttle valve (8) is in a closed state and the left side is in an open state; the hydraulic oil flowing into the fifth oil circuit (3f) opens the second hydraulically controlled one-way valve (7) in the positive direction and then enters the rod chamber of the hydraulic cylinder (5), and the hydraulic oil pushes the piston in the hydraulic cylinder (5) to move to the left, and the piston rod retracts and drives The vehicle door is closed; the hydraulic oil flowing into the second auxiliary oil circuit (3g) causes the first hydraulically controlled one-way valve (6) to conduct in the reverse direction, and when the piston in the hydraulic cylinder (5) moves to the left, the hydraulic oil in the rodless chamber of the hydraulic cylinder (5) flows through the third oil circuit (3c) and the first hydraulically controlled one-way valve (6), a portion of the hydraulic oil is sucked by the bidirectional hydraulic pump (2), and the other portion of the hydraulic oil enters the shuttle valve (8) through the left end interface of the shuttle valve (8), and then flows into the oil tank (4) through the first oil circuit (3a).

7. The vehicle door opening and closing method according to claim 6, characterized in that: After the motor (1) is started, if the motor (1) is powered off, the bidirectional hydraulic pump (2) cannot output hydraulic oil. At this time, the first hydraulically controlled one-way valve (6) and the second hydraulically controlled one-way valve (7) are in a closed state. The first hydraulically controlled one-way valve (6) and the second hydraulically controlled one-way valve (7) seal the hydraulic oil in the hydraulic cylinder (5), so that the hydraulic cylinder (5) is in a holding state.

8. A vehicle door opening and closing method according to claim 6 or 7, characterized in that: The door opening process also includes: S13, after the motor (1) drives the bidirectional hydraulic pump (2) to rotate forward, the hydraulic oil output from the first output end of the bidirectional hydraulic pump (2) also flows into the third auxiliary oil circuit (3i) and then enters the first overflow valve (9), thereby increasing the opening force of the first overflow valve (9). If the hydraulic cylinder (5) encounters a large load during the door opening process, the pressure in the rodless portion of the hydraulic cylinder (5) increases and exceeds the opening force of the first overflow valve (9), thereby opening the first overflow valve (9). The hydraulic oil in the rodless portion of the hydraulic cylinder (5) flows through the first overflow valve (9), the sixth oil circuit (3h), and the first oil circuit (3a) and then enters the oil tank (4), thereby releasing the pressure generated when encountering a large load.

9. A vehicle door opening and closing method according to claim 6 or 7, characterized in that: The closing process also includes: S23, after the motor (1) drives the bidirectional hydraulic pump (2) to reverse, the hydraulic oil output from the second output end of the bidirectional hydraulic pump (2) also flows into the fourth auxiliary oil circuit (3k) and then enters the second relief valve (10), thereby increasing the opening force of the second relief valve (10). If the hydraulic cylinder (5) encounters a large load during the closing process, the pressure in the rod of the hydraulic cylinder (5) increases and exceeds the opening force of the second relief valve (10), thereby opening the second relief valve (10). The hydraulic oil in the rod of the hydraulic cylinder (5) flows through the second relief valve (10), the seventh oil circuit (3j), and the first oil circuit (3a), and then enters the oil tank (4), thereby releasing the pressure generated when encountering a large load.

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