A floating control device and method for hydraulic tilting and lifting cylinder of a commercial vehicle cab

Abstract

The present application relates to a floating control device and method for a hydraulic tilting lifting cylinder of a commercial vehicle cab, comprising: a lifting cylinder, which comprises an outer cylinder and an inner cylinder connected in a sliding manner in the outer cylinder by an outer piston, the outer piston dividing the outer cylinder into a first rodless chamber and a first rod chamber; a piston rod is connected in a sliding manner in the inner cylinder by an inner piston, the inner piston dividing the inner cylinder into a second rodless chamber and a second rod chamber, the top of the first rodless chamber is connected to the bottom of the second rodless chamber, and the bottom of the second rod chamber is connected to the first rod chamber; a control system, which comprises a two-position two-way valve for controlling the opening or closing of the first rod chamber, a stop valve for controlling the opening or closing of the first rodless chamber, and a two-position four-way valve connecting the first rodless chamber and the second rod chamber; the two-position four-way valve is connected to a hydraulic pump, and a pressure sensor for controlling the switch of the stop valve is connected between the hydraulic pump and the two-position four-way valve. The lifting cylinder of the present application can be quickly extended and retracted and floated freely, ensuring driving comfort.

Description

Technical Field

[0001] The present application relates to the technical field of commercial vehicle cabs, and in particular to a floating control device and method for a hydraulic flip lift cylinder of a commercial vehicle cab. Background Art

[0002] In order to improve the riding comfort of the cab, commercial vehicles use semi-floating or full-floating suspension. In order to improve the convenience of engine maintenance and repair, the cab is flipped by extending and retracting the hydraulic cylinder. Since the cab suspension has a certain amount of up and down jumping, the hydraulic cylinder needs to have a certain amount of floating when it is extended and retracted.

[0003] The existing floating lifting cylinder has a small floating range due to structural and functional limitations. After the cylinder enters the floating range, it loses pressure control, causing the cab to flip and stall, posing certain safety hazards. When entering the lifting working state in the floating range, the hydraulic pipeline needs to be compensated, the response time is long, and the working efficiency is low. Summary of the invention

[0004] The embodiment of the present application provides a floating control device and method for a hydraulic tilt lifting cylinder of a commercial vehicle cab, so as to solve the problems of long response time and low working efficiency when the floating lifting cylinder enters the lifting working state in the related art.

[0005] A first aspect of an embodiment of the present application provides a floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab, comprising:

[0006] A lifting cylinder, the lifting cylinder comprising an outer cylinder barrel and an inner cylinder barrel slidably connected in the outer cylinder barrel through an outer piston, the outer piston dividing the outer cylinder barrel into a first rodless chamber and a first rod chamber;

[0007] A piston rod is slidably connected in the inner cylinder through an inner piston, and the inner piston divides the inner cylinder into a second rodless chamber and a second rod chamber, the top of the first rodless chamber is connected to the bottom of the second rodless chamber, and the bottom of the second rod chamber is connected to the first rod chamber;

[0008] A control system, the control system comprising a two-position two-way valve for controlling the opening or closing of the first rod chamber, a stop valve for controlling the opening or closing of the first rodless chamber, and a two-position four-way valve for connecting the first rodless chamber and the second rod chamber;

[0009] The two-position four-way valve is connected to a hydraulic pump, and a pressure sensor for controlling the switch of a stop valve is connected between the hydraulic pump and the two-position four-way valve.

[0010] In some embodiments: the top of the inner cylinder is provided with a first oil inlet and outlet connected to the port B of the two-position four-way valve, and the first oil inlet and outlet is connected to the second rod chamber;

[0011] The bottom of the outer cylinder is provided with a second oil inlet and outlet connected to the port A of the two-position four-way valve, and the second oil inlet and outlet are connected to the first rodless chamber;

[0012] The first oil inlet and outlet are connected to the B port of the two-position four-way valve through the fourth pipeline, and the second oil inlet and outlet are connected to the A port of the two-position four-way valve through the third pipeline.

[0013] In some embodiments: the P port of the two-position four-way valve is connected to the outlet end of the hydraulic pump through the second pipeline, the inlet end of the hydraulic pump is connected to the hydraulic oil tank through the first pipeline, and the O port of the two-position four-way valve is connected to the hydraulic oil tank.

[0014] In some embodiments: the pressure sensor is connected to the second pipeline, and the shut-off valve is closed when the pressure sensor detects that the oil pressure in the second pipeline is greater than a set value.

[0015] In some embodiments: a third oil inlet and outlet connected to the stop valve is provided at the bottom of the outer cylinder, and the third oil inlet and outlet is connected to the first rodless chamber;

[0016] The stop valve is connected to the third oil inlet and outlet through the sixth pipeline. When the stop valve is opened, the oil discharged from the first rodless chamber is discharged into the hydraulic oil tank through the seventh pipeline.

[0017] In some embodiments: a fourth oil inlet and outlet connected to the two-position two-way valve is provided on the top of the outer cylinder, and the fourth oil inlet and outlet is connected to the first rod chamber;

[0018] One end of the two-position two-way valve is connected to the fourth oil inlet and outlet through a fifth pipeline, and when the two-position two-way valve is opened, the oil in the first rod chamber is discharged;

[0019] The other end of the two-position two-way valve is connected to the hydraulic oil tank through the seventh pipeline to discharge the oil discharged from the first rod chamber into the hydraulic oil tank.

[0020] In some embodiments: the two-position two-way valve and the two-position four-way valve are hydraulic valves or solenoid valves, and the control system also includes an electric control box for controlling the extension or retraction of the lifting cylinder, and the electric control box is provided with a manual switch for controlling the action of the two-position two-way valve and the two-position four-way valve.

[0021] A second aspect of the present application provides a method for a floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab, wherein the method uses the floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab as described in any one of the above embodiments, and the method comprises:

[0022] When the driver needs to flip and lift, the two-position four-way valve is controlled by the manual switch to be in the state of output at port A and reflux at port B, the two-position two-way valve is opened and the fifth pipeline and the seventh pipeline are connected;

[0023] The hydraulic pump is started to generate oil pressure in the second pipeline, and the stop valve is closed through the output signal of the pressure sensor to disconnect the sixth pipeline and the seventh pipeline;

[0024] The second pipeline allows the hydraulic oil to enter the two-position four-way valve through the P port, and then is injected into the first rodless chamber from the A port through the third pipeline to push the outer piston and the inner cylinder upward to the upper limit position, and then continue to push the inner piston and the piston rod to the upper limit position;

[0025] The oil in the first rod chamber is discharged into the hydraulic oil tank through the fifth pipeline, the two-position two-way valve and the seventh pipeline in sequence, and the oil in the second rod chamber is discharged into the hydraulic oil tank through the fourth pipeline, the two-position four-way valve and the seventh pipeline in sequence.

[0026] In some embodiments: the method further comprises:

[0027] When the driver needs to flip and descend, the two-position four-way valve is controlled by the manual switch to be in the state of output at port B and reflux at port A, the two-position two-way valve is closed and the fifth pipeline and the seventh pipeline are cut off;

[0028] The hydraulic pump is started to generate oil pressure in the second pipeline, and the stop valve is closed through the output signal of the pressure sensor to disconnect the sixth pipeline and the seventh pipeline;

[0029] The second pipeline allows the hydraulic oil to enter the two-position four-way valve through the P port, and is injected into the second rod chamber from the B port through the fourth pipeline to push the inner piston and the piston rod downward to the lower limit position. The second rod chamber is connected with the first rod chamber, and then continues to push the outer piston and the inner cylinder to return to the cab;

[0030] The oil in the first rodless chamber is discharged into the hydraulic oil tank through the third pipeline, the A port and the O port of the two-position four-way valve and the seventh pipeline in sequence.

[0031] In some embodiments: the method further comprises:

[0032] When the cab returns to its original position, the two-position four-way valve is controlled by a manual switch to be in the state of output at port A and return flow at port B, and the two-position two-way valve is controlled to open and connect the fifth pipeline and the seventh pipeline;

[0033] The hydraulic pump is controlled to stop working, and the pressure sensor outputs a signal to open the stop valve, and the stop valve connects the sixth pipeline and the seventh pipeline;

[0034] The hydraulic oil pressure in the first rodless chamber and the first rod chamber is released, so that the inner cylinder can move freely up and down with the cab, thereby realizing free floating of the lifting cylinder.

[0035] The beneficial effects of the technical solution provided by this application include:

[0036] The embodiment of the present application provides a floating control device and method for a hydraulic flip and lifting cylinder of a commercial vehicle cab. Since the floating control device for the hydraulic flip and lifting cylinder of a commercial vehicle cab of the present application is provided with a lifting cylinder, the lifting cylinder includes an outer cylinder barrel and an inner cylinder barrel slidably connected to the outer cylinder barrel by an outer piston, the outer piston divides the outer cylinder barrel into a first rodless chamber and a first rod chamber; a piston rod is slidably connected to the inner cylinder barrel by an inner piston, the inner piston divides the inner cylinder barrel into a second rodless chamber and a second rod chamber, the top of the first rodless chamber is connected to the bottom of the second rodless chamber, and the bottom of the second rod chamber is connected to the first rod chamber; a control system, the control system includes a two-position two-way valve for controlling the opening or closing of the first rodless chamber, a stop valve for controlling the opening or closing of the first rodless chamber, and a two-position four-way valve connecting the first rodless chamber and the second rod chamber; the two-position four-way valve is connected to a hydraulic pump, and a pressure sensor for controlling the switch of the stop valve is connected between the hydraulic pump and the two-position four-way valve.

[0037] Therefore, the commercial vehicle cab hydraulic flip lift cylinder floating control device applied for realizes the telescopic action of the lifting cylinder to flip and lift the cab and flip and lower the cab through the cooperation of the two-position two-way valve, the two-position four-way valve and the stop valve. When the flip and lift cab is in action, the high-pressure oil enters from the P port of the two-position four-way valve, and flows out from the A port into the first rodless cavity and the second rodless cavity, so that the lifting cylinder is extended to achieve the lifting effect. At this time, the oil pressure of the first rod cavity and the second rod cavity increases, and the oil in the first rod cavity is discharged into the hydraulic oil tank through the two-position two-way valve; the oil in the second rod cavity flows out and flows back to the B port of the two-position four-way valve to be discharged into the hydraulic oil tank, so that the lifting cylinder is extended faster, shortening the time required for cab lifting and improving efficiency. At the same time, after the hydraulic pump is turned off, the stop valve and the two-position two-way valve are opened, so that the lifting cylinder can float up and down with the cab, improve the stability of the cab during driving, and ensure driving comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 This is a schematic diagram of the structure implemented in this application.

[0040] Reference numerals:

[0041] 1. Piston rod; 2. Inner cylinder; 3. Outer cylinder; 4. Inner piston; 5. Outer piston; 6. Two-position two-way valve; 7. Stop valve; 8. Pressure sensor; 9. Two-position four-way valve; 10. Hydraulic pump; 11. Hydraulic oil tank; 12. First rodless chamber; 13. First rod chamber; 14. Second rod chamber; A1. Second oil inlet and outlet; B1. First oil inlet and outlet; C1. Third oil inlet and outlet; C2. Fourth oil inlet and outlet; g1. First pipeline; g2. Second pipeline; g3. Third pipeline; g4. Fourth pipeline; g5. Fifth pipeline; g6. Sixth pipeline; g7. Seventh pipeline. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0043] The embodiment of the present application provides a floating control device and method for a hydraulic flip lifting cylinder of a commercial vehicle cab, which can solve the problems of long response time and low working efficiency when the floating lifting cylinder enters a lifting working state in the related art.

[0044] See also Figure 1 As shown, the first aspect of the embodiment of the present application provides a floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab, comprising:

[0045] The lifting cylinder comprises an outer cylinder 3 and an inner cylinder 2 slidably connected to the outer cylinder 3 through an outer piston 5, and the outer piston 5 divides the outer cylinder 3 into a first rodless chamber 12 and a first rod chamber 13. Both the outer cylinder 3 and the inner cylinder 2 are cylindrical structures with an opening at the top and closed around, and the height of the inner cylinder 2 is greater than that of the outer cylinder 3.

[0046] A piston rod 1 is slidably connected to the inner cylinder 2 via an inner piston 4. The inner piston 4 divides the inner cylinder 2 into a second rodless chamber and a second rod chamber 14. The top of the first rodless chamber 12 is connected to the bottom of the second rodless chamber, and the bottom of the second rod chamber 14 is connected to the first rod chamber 13, so that the inner cylinder 2 can be extended before the piston rod 1 and retracted after the piston rod 1.

[0047] The control system includes a two-position two-way valve 6 for controlling the opening or closing of the first rod chamber 13, a stop valve 7 for controlling the opening or closing of the first rodless chamber 12, and a two-position four-way valve 9 for connecting the first rodless chamber 12 and the second rod chamber 14. The two-position four-way valve 9 is connected to a hydraulic pump 10, and a pressure sensor 8 for controlling the switch of the stop valve 7 is connected between the hydraulic pump 10 and the two-position four-way valve 9.

[0048] The floating control device for the hydraulic tilting and lifting cylinder of the cab of a commercial vehicle of the embodiment of the application realizes the telescopic action of the lifting cylinder to tilt and lift the cab and tilt and lower the cab through the cooperation of the two-position two-way valve 6, the two-position four-way valve 9 and the stop valve 7. When the cab is tilted and lifted, the high-pressure oil enters from the P port of the two-position four-way valve 9, and flows out from the A port into the first rodless cavity 12 and the second rodless cavity, so that the lifting cylinder is extended to achieve the lifting effect.

[0049] At this time, the oil pressure in the first rod chamber 13 and the second rod chamber 14 increases, and the oil in the first rod chamber 13 is discharged into the hydraulic oil tank 11 through the two-position two-way valve 6; the oil in the second rod chamber 14 flows out, and flows back to the B port and the O port of the two-position four-way valve 9 and is finally discharged into the hydraulic oil tank 11, so that the lifting cylinder extends faster, shortening the time required for lifting the cab and improving efficiency.

[0050] When the cab is flipped and lowered, the high-pressure oil enters from the P port of the two-position four-way valve 9 and flows out from the B port into the second rod chamber 14 and the first rod chamber 13, shortening the lifting cylinder to achieve the lowering effect.

[0051] At this time, the oil pressure in the first rodless chamber 12 and the second rodless chamber increases, and the oil in the first rodless chamber 12 enters through the A port of the two-position four-way valve 9 and is discharged to the hydraulic oil tank 11 through the O port, making the lifting cylinder shorten faster, shortening the time required to shorten the cab and improving efficiency.

[0052] At the same time, after the hydraulic pump 10 is turned off, the stop valve 7 and the two-position two-way valve 6 are opened, so that the lifting cylinder can float up and down with the cab, thereby improving the stability of the cab during driving and ensuring driving comfort.

[0053] In some optional embodiments: See Figure 1 As shown, an embodiment of the present application provides a floating control device for a hydraulic flip lifting cylinder of a commercial vehicle cab, in which a first oil inlet and outlet B1 connected to port B in a two-position four-way valve 9 is provided at the top of the cylinder 2, and the first oil inlet and outlet B1 is connected to the second rod chamber 14.

[0054] The bottom of the outer cylinder 3 is provided with a second oil inlet and outlet port A1 connected to the port A of the two-position four-way valve 9, and the second oil inlet and outlet port A1 is connected to the first rodless chamber 12. The first oil inlet and outlet port B1 is connected to the port B of the two-position four-way valve 9 through the fourth pipeline g4, and the second oil inlet and outlet port A1 is connected to the port A of the two-position four-way valve 9 through the third pipeline g3.

[0055] The P port of the two-position four-way valve 9 is connected to the outlet end of the hydraulic pump 10 through the second pipeline g2, the inlet end of the hydraulic pump 10 is connected to the hydraulic oil tank 11 through the first pipeline g1, and the O port of the two-position four-way valve 9 is connected to the hydraulic oil tank 11.

[0056] The pressure sensor 8 is connected to the second pipeline g2. When the pressure sensor 8 detects that the oil pressure in the second pipeline g2 is greater than the set value, the stop valve 7 is closed. The bottom of the outer cylinder 3 is provided with a third oil inlet and outlet C1 connected to the stop valve 7. The third oil inlet and outlet C1 is connected to the first rodless chamber 12.

[0057] The stop valve 7 is connected to the third oil inlet and outlet C1 through the sixth pipeline g6. When the stop valve 7 is opened, the oil discharged from the first rodless chamber 12 is discharged into the hydraulic oil tank 11 through the seventh pipeline g7.

[0058] In some optional embodiments: See Figure 1 As shown, the embodiment of the present application provides a floating control device for a hydraulic tilting and lifting oil cylinder of a commercial vehicle cab, wherein a fourth oil inlet and outlet C2 connected to a two-position two-way valve 6 is provided at the top of the outer cylinder 3 of the device, and the fourth oil inlet and outlet C2 is connected to the first rod chamber 13. One end of the two-position two-way valve 6 is connected to the fourth oil inlet and outlet C2 through a fifth pipeline g5, and when the two-position two-way valve 6 is opened, the oil in the first rod chamber 13 is discharged.

[0059] The other end of the two-position two-way valve 6 is connected to the hydraulic oil tank 11 through the seventh pipeline g7 to discharge the oil discharged from the first rod chamber 13 into the hydraulic oil tank 11. The two-position two-way valve 6 and the two-position four-way valve 9 are preferably hydraulic valves or solenoid valves. The control system also includes an electric control box for controlling the extension or retraction of the lifting cylinder. The electric control box is provided with a manual switch for controlling the action of the two-position two-way valve 6 and the two-position four-way valve 9. The manual switch controls the two-position two-way valve 6 and the two-position four-way valve 9 to automatically control the extension and retraction of the lifting oil.

[0060] See also Figure 1 As shown, the second aspect of the embodiment of the present application provides a method for a floating control device for a hydraulic flip lift cylinder of a commercial vehicle cab, the method using the floating control device for a hydraulic flip lift cylinder of a commercial vehicle cab as described in any one of the above embodiments, the method comprising:

[0061] Step 1: When the vehicle needs to be flipped and lifted, the two-position four-way valve 9 is controlled by a manual switch to be in the state of output at port A and reflux at port B, the two-position two-way valve 6 is opened and the fifth pipeline g5 and the seventh pipeline g7 are connected.

[0062] Step 2: Start the hydraulic pump 10 to generate oil pressure in the second pipeline g2, and output a signal through the pressure sensor 8 to close the stop valve 7, so that the stop valve 7 disconnects the sixth pipeline g6 and the seventh pipeline g7.

[0063] Step 3, the second pipeline g2 brings the hydraulic oil into the two-position four-way valve 9 through the P port, and injects it into the first rodless chamber 12 from the A port through the third pipeline g3 to push the outer piston 5 and the inner cylinder 2 upward to the upper limit position, and then continue to push the inner piston 4 and the piston rod 1 to the upper limit position.

[0064] Step 4, the oil in the first rod chamber 13 is discharged into the hydraulic oil tank 11 through the fifth pipeline g5, the two-position two-way valve 6 and the seventh pipeline g7 in sequence, and the oil in the second rod chamber 14 is discharged into the hydraulic oil tank 11 through the fourth pipeline g4, the two-position four-way valve 9 and the seventh pipeline g7 in sequence.

[0065] In some alternative embodiments: See Figure 1 As shown, the embodiment of the application provides a method for a floating control device of a hydraulic flip lifting cylinder of a commercial vehicle cab, and the method also includes:

[0066] Step 5, when the vehicle needs to be turned over and lowered, the two-position four-way valve 9 is controlled by a manual switch to be in the state of output at port B and reflux at port A, the two-position two-way valve 6 is closed and the fifth pipeline g5 and the seventh pipeline g7 are cut off.

[0067] Step 6: Start the hydraulic pump 10 to generate oil pressure in the second pipeline g2, and output a signal through the pressure sensor 8 to close the stop valve 7, so that the stop valve 7 disconnects the sixth pipeline g6 and the seventh pipeline g7.

[0068] Step 7, the second pipeline g2 allows the hydraulic oil to enter the two-position four-way valve 9 through the P port, and is injected into the second rod chamber 14 from the B port through the fourth pipeline g4 to push the inner piston 4 and the piston rod 1 downward to the lower limit position. The second rod chamber 14 is connected to the first rod chamber 13, and then continues to push the outer piston 5 and the inner cylinder 2 to return to the cab.

[0069] Step 8: The oil in the first rodless chamber 12 is discharged into the hydraulic oil tank 11 through the third pipeline g3, the A port and the O port of the two-position four-way valve 9 and the seventh pipeline g7 in sequence.

[0070] In some alternative embodiments: See Figure 1 As shown, the embodiment of the application provides a method for a floating control device of a hydraulic flip lifting cylinder of a commercial vehicle cab, and the method also includes:

[0071] Step 9, when the cab returns to its original position, the two-position four-way valve 9 is controlled by the manual switch to be in the state of output at port A and reflux at port B, and the two-position two-way valve 6 is controlled to open and connect the fifth pipeline g5 and the seventh pipeline g7.

[0072] Step 10, control the hydraulic pump 10 to stop working, the pressure sensor 8 outputs a signal to open the stop valve 7, and the stop valve 7 connects the sixth pipeline g6 and the seventh pipeline g7.

[0073] Step 11, the two-position two-way valve 6, the stop valve 7 and the two-position four-way valve 9 release the hydraulic oil pressure in the first rodless chamber 12 and the first rod chamber 13, so that the inner cylinder 2 can move freely up and down with the cab, realizing the free floating of the lifting cylinder.

[0074] When the cab moves upward, the oil in the hydraulic oil tank 11 is sucked into the P port of the two-position four-way valve 9 through the first pipeline g1 and the second pipeline g2, and is replenished into the first rodless chamber 12 through the A port and the third pipeline g3. The oil in the first rod chamber 13 enters the two-position two-way valve 6 through the fifth pipeline g5 and is discharged into the hydraulic oil tank 11 from the seventh pipeline g7. The oil in the second rod chamber 14 enters the B port through the fourth pipeline g4 and enters the hydraulic oil tank 11 from the O port through the seventh pipeline g7.

[0075] When the cab moves downward, the oil in the first rodless chamber 12 enters the hydraulic oil tank 11 through the stop valve 7 and the seventh pipeline g7, and the two-position two-way valve 6 draws the oil in the hydraulic oil tank 11 through the seventh pipeline g7 and replenishes it into the first rod chamber g5 through the fifth pipeline g5.

[0076] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0077] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0078] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab, characterized in that: include: A lifting cylinder, comprising an outer cylinder barrel (3) and an inner cylinder barrel (2) slidably connected to the outer cylinder barrel (3) via an outer piston (5), wherein the outer piston (5) divides the outer cylinder barrel (3) into a first rodless chamber (12) and a first rod chamber (13); The inner cylinder (2) is slidably connected to a piston rod (1) via an inner piston (4), and the inner piston (4) divides the inner cylinder (2) into a second rodless chamber and a second rod chamber (14), the top of the first rodless chamber (12) is connected to the bottom of the second rodless chamber, and the bottom of the second rod chamber (14) is connected to the first rod chamber (13); A control system, the control system comprising a two-position two-way valve (6) for controlling the opening or closing of the first rod chamber (13), a stop valve (7) for controlling the opening or closing of the first rodless chamber (12), and a two-position four-way valve (9) for connecting the first rodless chamber (12) and the second rod chamber (14); The two-position four-way valve (9) is connected to a hydraulic pump (10), and a pressure sensor (8) for controlling the switch of the stop valve (7) is connected between the hydraulic pump (10) and the two-position four-way valve (9); The top of the inner cylinder (2) is provided with a first oil inlet and outlet (B1) connected to the B port of the two-position four-way valve (9), and the first oil inlet and outlet (B1) is connected to the second rod chamber (14); The bottom of the outer cylinder (3) is provided with a second oil inlet and outlet (A1) connected to the A port of the two-position four-way valve (9), and the second oil inlet and outlet (A1) is connected to the first rodless chamber (12); The first oil inlet and outlet port (B1) is connected to the B port of the two-position four-way valve (9) through the fourth pipeline (g4), and the second oil inlet and outlet port (A1) is connected to the A port of the two-position four-way valve (9) through the third pipeline (g3).

2. A floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 1, characterized in that: The P port of the two-position four-way valve (9) is connected to the outlet end of the hydraulic pump (10) via a second pipeline (g2), the inlet end of the hydraulic pump (10) is connected to the hydraulic oil tank (11) via a first pipeline (g1), and the O port of the two-position four-way valve (9) is in communication with the hydraulic oil tank (11).

3. A floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 2, characterized in that: The pressure sensor (8) is connected to the second pipeline (g2), and the stop valve (7) is closed when the pressure sensor (8) detects that the oil pressure in the second pipeline (g2) is greater than a set value.

4. A floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 1, characterized in that: The bottom of the outer cylinder (3) is provided with a third oil inlet and outlet (C1) connected to the stop valve (7), and the third oil inlet and outlet (C1) is connected to the first rodless chamber (12); The stop valve (7) is connected to the third oil inlet and outlet (C1) via the sixth pipeline (g6). When the stop valve (7) is opened, the oil discharged from the first rodless chamber (12) is discharged into the hydraulic oil tank (11) via the seventh pipeline (g7).

5. The floating control device for hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 1, characterized in that: A fourth oil inlet and outlet (C2) connected to a two-position two-way valve (6) is provided at the top of the outer cylinder (3); the fourth oil inlet and outlet (C2) is connected to the first rod chamber (13); One end of the two-position two-way valve (6) is connected to the fourth oil inlet and outlet (C2) through a fifth pipeline (g5), and when the two-position two-way valve (6) is opened, the oil in the first rod chamber (13) is discharged; The other end of the two-position two-way valve (6) is connected to the hydraulic oil tank (11) through the seventh pipeline (g7) to discharge the oil discharged from the first rod chamber (13) into the hydraulic oil tank (11).

6. A floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 1, characterized in that: The two-position two-way valve (6) and the two-position four-way valve (9) are hydraulic valves or solenoid valves. The control system also includes an electric control box for controlling the extension or retraction of the lifting cylinder. The electric control box is provided with a manual switch for controlling the operation of the two-position two-way valve (6) and the two-position four-way valve (9).

7. A method for a floating control device for a hydraulic tilting and lifting cylinder of a commercial vehicle cab, characterized in that: The method uses the floating control device for the hydraulic tilting and lifting cylinder of a commercial vehicle cab according to any one of claims 1 to 6, and the method comprises: When the vehicle needs to be turned over and lifted, the two-position four-way valve (9) is controlled by a manual switch to be in a state of output at port A and reflux at port B, the two-position two-way valve (6) is opened and the fifth pipeline (g5) and the seventh pipeline (g7) are connected; Starting the hydraulic pump (10) to generate oil pressure in the second pipeline (g2), and outputting a signal through the pressure sensor (8) to close the stop valve (7), thereby disconnecting the sixth pipeline (g6) and the seventh pipeline (g7); The second pipeline (g2) allows the hydraulic oil to enter the two-position four-way valve (9) through the P port, and is injected into the first rodless chamber (12) from the A port through the third pipeline (g3) to push the outer piston (5) and the inner cylinder (2) upward to the upper limit position, and then continue to push the inner piston (4) and the piston rod (1) to the upper limit position; The oil in the first rod chamber (13) is discharged into the hydraulic oil tank (11) through the fifth pipeline (g5), the two-position two-way valve (6) and the seventh pipeline (g7) in sequence, and the oil in the second rod chamber (14) is discharged into the hydraulic oil tank (11) through the fourth pipeline (g4), the two-position four-way valve (9) and the seventh pipeline (g7) in sequence.

8. A method for controlling the floating of a hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 7, characterized in that: The method further comprises: When the vehicle needs to be turned over and lowered, the two-position four-way valve (9) is controlled by a manual switch to be in a state of output at port B and reflux at port A, the two-position two-way valve (6) is closed, and the fifth pipeline (g5) and the seventh pipeline (g7) are cut off; Starting the hydraulic pump (10) to generate oil pressure in the second pipeline (g2), and outputting a signal through the pressure sensor (8) to close the stop valve (7), thereby disconnecting the sixth pipeline (g6) and the seventh pipeline (g7); The second pipeline (g2) allows the hydraulic oil to enter the two-position four-way valve (9) through the P port, and is injected into the second rod chamber (14) from the B port through the fourth pipeline (g4) to push the inner piston (4) and the piston rod (1) downward to the lower limit position, and the second rod chamber (14) is connected with the first rod chamber (13), and then continues to push the outer piston (5) and the inner cylinder (2) to return to the cab; The oil in the first rodless chamber (12) is discharged into the hydraulic oil tank (11) through the third pipeline (g3), the A port and the O port of the two-position four-way valve (9) and the seventh pipeline (g7) in sequence.

9. A method for controlling the floating of a hydraulic tilting and lifting cylinder of a commercial vehicle cab as claimed in claim 7 or 8, characterized in that: The method further comprises: When the cab returns to its original position, the two-position four-way valve (9) is controlled by a manual switch to be in a state of output at port A and return flow at port B, and the two-position two-way valve (6) is controlled to open and connect the fifth pipeline (g5) and the seventh pipeline (g7); The hydraulic pump (10) is controlled to stop working, and the pressure sensor (8) outputs a signal to open the stop valve (7), and the stop valve (7) connects the sixth pipeline (g6) and the seventh pipeline (g7); The hydraulic oil pressure in the first rodless chamber (12) and the first rod chamber (13) is released, so that the inner cylinder barrel (2) can freely move up and down with the cab, thereby realizing free floating of the lifting cylinder.

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