Film hydraulic system and control method thereof, cotton picker film system and cotton picker

Abstract

The application discloses a film covering hydraulic system and a control method thereof, a cotton picker film covering system and a cotton picker. The film covering hydraulic system comprises a packing film, a pinch roll, a rotating speed sensor, a photoelectric sensor, an electric proportional speed regulating valve, a first electromagnetic reversing valve, a back pressure adjusting device, a hydraulic motor, a brake device, a first check valve, a second check valve and a second electromagnetic reversing valve. After sending a film covering fault, the application can prevent the film blocking and winding phenomenon, can automatically recover the packing film when the film blocking occurs through reverse rotation, reduces the manual cleaning operation, reduces the operation strength, improves the work efficiency, reduces the packing film waste, adjusts the size of the hydraulic motor back pressure through the back pressure adjusting device, changes the tension applied to the packing film, ensures the uniformity of the tension of the bale after baling, avoids the film breaking and bale explosion phenomenon in the film covering process, and can perform secondary film sending after the first film sending failure, and improves the film covering success rate of the film covering system.

Description

Technical Field

[0001] The present application relates to the technical field of agricultural machinery, and in particular to a mulching hydraulic system and a control method thereof, a cotton picker mulching system, and a cotton picker. Background Art

[0002] With the development of agricultural machinery, cotton picking has become increasingly dependent on cotton pickers. These machines not only address labor shortages during the cotton harvest season, but also save labor costs and significantly improve cotton picking efficiency. However, cotton is relatively soft after picking, making it difficult to transport and store. To improve work efficiency and cotton transportation, cotton must be baled. The film coating system for cotton bales is an important step in ensuring the quality of the film coating. Therefore, improving the quality of the film coating on cotton bales is particularly important.

[0003] Regarding the film covering system of cotton pickers, the current technology has the following deficiencies:

[0004] 1. When the existing cotton picker film covering system fails to deliver the film into the baling box, a large amount of baling film will accumulate on the film support frame or be wrapped around the pinch roller. After the baling film is piled up or wrapped, it needs to be cleaned manually. In severe cases, the unbaled cotton in the baling box needs to be removed before the accumulated baling film can be cleaned, which seriously affects the working efficiency.

[0005] 2. The packaging film cannot be automatically recycled after the lamination fails, and needs to be manually cleaned after the machine is shut down. This process is time-consuming and labor-intensive, affecting the operating efficiency. In addition, the packaging film after cleaning cannot be reused, resulting in serious waste.

[0006] 3. The existing cotton picker covering device uses an electromagnetic clutch to drive the rotation of the pinch roller to feed the film. The tension of the packing film is extended by the speed difference between the packing belt speed and the film feeding speed to tension the packing film. The tension applied to the packing film during the covering process cannot be adjusted. The ductility parameters of the packing film produced by different manufacturers are different. Cold weather also has a great influence on the ductility of the packing film. Relying on the speed difference to extend the packing film will result in inconsistent tension on the cotton bales, and even the packing film will be torn during the covering process or the cotton bales will explode in the later stage of being packaged. Summary of the Invention

[0007] On the one hand, an embodiment of the present application provides a laminating hydraulic system to solve the technical problems of the existing cotton picker laminating device, such as the packing film being piled or wrapped after the film fails to be delivered into the packing box, the packing film cannot be automatically recovered, and the tension on the packing film is difficult to control.

[0008] The technical solutions adopted in this application are as follows:

[0009] A laminating hydraulic system includes a packaging film, a pinch roller, a speed sensor, a photoelectric sensor, an electric proportional speed regulating valve, a first electromagnetic reversing valve, a back pressure regulating device, a hydraulic motor, a braking device, a first one-way valve, a second one-way valve, and a second electromagnetic reversing valve, wherein:

[0010] The oil inlet port P of the first solenoid reversing valve is connected to the electric proportional speed control valve and the output port of the hydraulic pump in sequence, the working port A is connected to the back pressure regulating device and the hydraulic motor in sequence, the working port B is connected to the other input port of the hydraulic motor through a pipeline, and the oil return port T is connected to the working port B through a first one-way valve on the one hand and to the oil tank through a second one-way valve on the other hand;

[0011] The output end of the hydraulic motor is connected to the pinch roller through the transmission shaft, driving the pinch roller to rotate and feed the packaging film into the packaging box;

[0012] The braking device is arranged relative to the transmission shaft and is used to brake the pinch roller;

[0013] The speed sensor is used to measure the speed of the pinch roller and the cumulative number of pulses, and convert the cumulative number of pulses into the length of the packaging film;

[0014] The photoelectric sensor is used to detect the identification code on the package and to determine whether the film feeding is completed.

[0015] Furthermore, the back pressure regulating device includes a balancing valve, one end of which is connected to the hydraulic motor, and the other end is connected to the working port A of the first electromagnetic reversing valve, and the hydraulic control port K of the balancing valve is connected to the working port B of the first electromagnetic reversing valve.

[0016] Furthermore, the back pressure regulating device includes an electric proportional relief valve and a third one-way valve arranged in parallel.

[0017] Furthermore, the braking device adopts a hydraulic braking device, which includes a hydraulic brake and a second electromagnetic reversing valve. The oil inlet P of the second electromagnetic reversing valve is connected to the hydraulic pump output port through a pipeline, the oil return port T is connected to the oil tank, and the working port A is connected to the hydraulic brake.

[0018] Furthermore, the hydraulic brake device also includes a pressure reducing valve, which is arranged on the pipeline between the oil inlet port P of the second electromagnetic reversing valve and the output port of the hydraulic pump.

[0019] Furthermore, the braking device adopts an electromagnetic brake.

[0020] On the other hand, the present application also provides a method for controlling a laminating hydraulic system, comprising the steps of:

[0021] Process of actively feeding the film into the packing box: After the cotton is packed and formed in the packing box, the braking device is in the brake release state, the electro-hydraulic proportional speed control valve is powered on with a power-on current of I1, the left position of the first electromagnetic directional control valve is powered on, and the high-pressure oil enters the hydraulic motor through the electro-hydraulic proportional speed control valve and the electromagnetic directional control valve. The hydraulic motor drives the pinch roller to rotate for active film feeding. The rotational speed sensor continuously detects the cumulative pulse number A1. When it detects that A1 > A0, the electro-hydraulic proportional speed control valve reduces the current to I0 to lower the rotational speed of the hydraulic motor. If the rotational speed sensor detects that the rotational speed of the pinch roller is n and n > n1, it is determined that the pinch roller has successfully fed the packing film into the packer and the passive film feeding process is executed; if the rotational speed sensor detects that the rotational speed of the pinch roller is n and n < n1, it is determined that the pinch roller has not fed the packing film into the packer and the re-filming process is executed; where A0 represents the judgment threshold for whether the packing film enters the box during the normal film covering process, and n1 is the rotational speed threshold of the hydraulic motor during active film feeding.

[0022] Passive film feeding process: After the pinch roller has successfully fed the packing film into the packer, the electro-hydraulic proportional speed control valve is powered on with a current of I0, and the active film feeding speed of the pinch roller is n0. At this time, n0 < n2, the film feeding speed of the pinch roller is less than the film covering speed of the packer, and the pinch roller rotates passively under the drive of the packing film. The hydraulic motor is in a negative load condition. The inlet flow rate Q0 of the hydraulic motor is less than the required flow rate Q2 for the operation of the hydraulic motor. At this time, the first check valve opens, and the oil is replenished to the inlet of the hydraulic motor through the first check valve. After subtracting the oil replenishment flow rate of the first check valve from the outlet flow rate Q2 of the hydraulic motor, the excess flow rate opens the second check valve and flows back to the oil tank. During the passive film feeding process, the back pressure regulating device adjusts the back pressure of the hydraulic motor to change the magnitude of the tension applied to the packing film.

[0023] Re-filming process: After the pinch roller actively feeds the film, if the packer fails to successfully feed the packing film into the packing box, at this time the film feeding speed of the pinch roller is n0, and the rotational speed n0 detected by the rotational speed sensor, n0 < n1. The right position of the first electromagnetic directional control valve is powered on, and the hydraulic motor rotates in reverse to drive the pinch roller to rotate in reverse to recover the film actively sent out by the pinch roller. The rotational speed sensor detects the cumulative pulse value A2. When A2 > A1, the left position of the first electromagnetic directional control valve is powered on, and the process of actively feeding the film into the packing box is continued. Among them, A1 is the cumulative pulse number detected by the rotational speed sensor during the forward film feeding process after the film covering starts.

[0024] Post-filming process: After the cotton bale is covered with film, the photoelectric sensor detects the unique identification code on the packing film, controls the electro-hydraulic proportional speed control valve, the first electromagnetic directional control valve, and the second electromagnetic directional control valve to lose power, and the braking device brakes the pinch roller. At this time, the pinch roller stops feeding the film, the packer rotates normally, the packing film is disconnected at the interface, and the film covering is completed.

[0025] Furthermore, if the secondary lamination process fails, a lamination failure prompt will be displayed on the display screen interface.

[0026] On the other hand, the present application also provides a cotton picker covering system, including a baler and the above-mentioned covering hydraulic system.

[0027] On the other hand, the present application also provides a cotton picker, including the cotton picker covering system.

[0028] Compared with the existing technology, this application has the following beneficial effects:

[0029] The present application provides a laminating hydraulic system and a control method thereof, a cotton picker laminating system, and a cotton picker. The laminating hydraulic system includes a baling film, a pinch roller, a speed sensor, a photoelectric sensor, an electric proportional speed regulating valve, a first electromagnetic reversing valve, a back pressure regulating device, a hydraulic motor, a braking device, a first one-way valve, a second one-way valve, and a second electromagnetic reversing valve. Specific advantages include:

[0030] 1. The film control hydraulic system of this application stops feeding the film if the packaging box fails to enter the box after the film fails to be laminated, so as to prevent film blockage and wrapping;

[0031] 2. The film laminating hydraulic system of the present application drives the pinch roller to rotate through the hydraulic motor, and can rotate in the opposite direction. When film blockage occurs, the packaging film can be automatically recovered, which reduces the manual cleaning operation, reduces the operation intensity, improves the work efficiency, and reduces the waste of packaging film.

[0032] 3. The laminating hydraulic system of the present application can adjust the back pressure of the hydraulic motor through the back pressure regulating device, thereby changing the tension applied to the baling film, ensuring that the tension of the cotton bales is consistent after baling. It can also accurately match the ductility, tension and other related parameters of the baling films produced by different manufacturers, thereby avoiding film breakage during the laminating process and the phenomenon of cotton bales exploding in the later stage of baling.

[0033] 4. The laminating hydraulic system of the present application detects the speed of the pinch roller by setting a speed sensor to detect whether the film feeding is successful. If the first film feeding fails, a second film feeding can be performed to improve the success rate of the laminating system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0035] Figure 1 It is a structural schematic diagram of the cotton picker covering system of the preferred embodiment of the present application.

[0036] Figure 2 It is a schematic diagram of the membrane hydraulic system of the preferred embodiment of the present application.

[0037] Figure 3 It is a schematic diagram of a membrane hydraulic system according to another preferred embodiment of the present application.

[0038] Figure 4 This is a schematic diagram of a cotton picker film covering control method according to a selected embodiment of the present application.

[0039] In the figure: 1. Packing film; 2. Pinch roller; 3. Speed ​​sensor; 4. Photoelectric sensor; 5. Electric proportional speed control valve; 6. First solenoid reversing valve; 7. Balance valve; 8. Hydraulic motor; 9. Hydraulic brake; 10. First one-way valve; 11. Second one-way valve; 12. Pressure reducing valve; 13. Second solenoid reversing valve; 14. Electric proportional overflow valve; 15. Third one-way valve. DETAILED DESCRIPTION

[0040] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] Reference Figure 1 and Figure 2 The preferred embodiment of the present application provides a laminating hydraulic system, including a packaging film 1, a pinch roller 2, a speed sensor 3, a photoelectric sensor 4, an electric proportional speed control valve 5, a first electromagnetic reversing valve 6, a back pressure regulating device, a hydraulic motor 8, a braking device, a first one-way valve 10, a second one-way valve 11, and a second electromagnetic reversing valve 13, wherein:

[0042] The oil inlet P of the first solenoid reversing valve 6 is connected in sequence to the electric proportional speed control valve 5 and the output port of the hydraulic pump, the working port A is connected in sequence to the back pressure regulating device and the hydraulic motor 8, the working port B is connected to the other input port of the hydraulic motor 8 through a pipeline, and the oil return port T is connected to the working port B through a first one-way valve 10 on the one hand and to the oil tank through a second one-way valve 11 on the other hand;

[0043] The output end of the hydraulic motor 8 is connected to the pinch roller 2 through a transmission shaft, driving the pinch roller 2 to rotate and feed the packaging film 1 into the packaging box;

[0044] The braking device is arranged relative to the transmission shaft and is used to brake the pinch roller 2;

[0045] The speed sensor 3 is used to measure the speed of the pinch roller 2 and the cumulative number of pulses, and convert the cumulative number of pulses into the length of the packaging film 1;

[0046] The photoelectric sensor 4 is used to detect the identification code on the package and to determine whether the film feeding is completed.

[0047] This embodiment provides a laminating hydraulic system, including a packaging film 1, a pinch roller 2, a speed sensor 3, a photoelectric sensor 4, an electric proportional speed control valve 5, a first electromagnetic reversing valve 6, a back pressure regulating device, a hydraulic motor 8, a brake device, a first one-way valve 10, a second one-way valve 11, and a second electromagnetic reversing valve 13. Specific advantages include:

[0048] 1. The film coating control hydraulic system of this embodiment can prevent film blocking and wrapping after the packaging box fails to coat the film;

[0049] 2. The laminating hydraulic system of this embodiment drives the pinch rollers to rotate through a hydraulic motor, which can also rotate in the opposite direction. When film blockage occurs, the laminating film can be automatically recovered, which reduces manual cleaning operations, reduces operating intensity, improves work efficiency, and reduces laminating film waste.

[0050] 3. The laminating hydraulic system of this embodiment can adjust the back pressure of the hydraulic motor through the back pressure regulating device, thereby changing the tension applied to the baling film, ensuring that the tension of the cotton bales is consistent after baling. It can also accurately match the ductility, tension and other related parameters of the baling films produced by different manufacturers, thereby avoiding film breakage during the laminating process and bale explosion in the later stages of baling.

[0051] 4. The laminating hydraulic system of this embodiment detects whether the film feeding is successful by setting a speed sensor to detect the speed of the pinch roller. If the first film feeding fails, a second film feeding can be performed to improve the success rate of the laminating system.

[0052] In a preferred embodiment of the present application, the back pressure regulating device includes a balancing valve 7, one end of the balancing valve 7 is connected to the hydraulic motor 8, and the other end is connected to the working port A of the first solenoid reversing valve 6, and the hydraulic control port K of the balancing valve 7 is connected to the working port B of the first solenoid reversing valve 6.

[0053] In this embodiment, the back pressure regulating device adopts a balancing valve 7, and the hydraulic control port K of the balancing valve 7 is associated with the inlet pressure of the hydraulic motor 8. At the same time, the back pressure of the hydraulic motor 8 is adjusted by adjusting the spring compression of the balancing valve 7, thereby changing the size of the tensioning force applied to the packaging film, ensuring that the tension of the cotton bales is consistent after packaging. The ductility tension and other related parameters of the packaging films produced by different manufacturers can also be accurately matched by adjusting the spring compression, thereby avoiding film breakage during the laminating process and cotton bales exploding in the later stage of packaging.

[0054] like Figure 3As shown, in another preferred embodiment of the present application, the back pressure regulating device includes an electric proportional relief valve 14 and a third one-way valve 15 arranged in parallel. Unlike the balancing valve 7, this embodiment can adjust the back pressure of the hydraulic motor 8 by adjusting the current of the electric proportional relief valve 14, thereby changing the tension applied to the packaging film to ensure that the tension of the cotton bales is consistent after packaging. It can also accurately match the ductility tension and other related parameters of the packaging film produced by different manufacturers by adjusting the current, thereby avoiding film breakage during the laminating process and cotton bales exploding in the later stage of packaging. The pipe laying is simpler and the control is more accurate and quick. Among them, the electric proportional relief valve 14 can set the back pressure corresponding to the tension under different manufacturers or different conditions into the program by setting the current. Different pressures can be set by selecting in the operation interface, which is more intelligent.

[0055] In addition, the back pressure regulating device of the present application can also be implemented by using other pressure reducing relief valves with back pressure function + one-way valve.

[0056] In a preferred embodiment of the present application, the braking device adopts a hydraulic braking device, which includes a hydraulic brake 9 and a second electromagnetic reversing valve 13. The oil inlet P of the second electromagnetic reversing valve 13 is connected to the hydraulic pump output port through a pipeline, the oil return port T is connected to the oil tank, and the working port A is connected to the hydraulic brake 9.

[0057] When the cotton bale starts to be coated, the second electromagnetic reversing valve 13 is energized, and the pressure oil enters the brake 9 through the second electromagnetic reversing valve 13, thereby releasing the brake of the pinch roller 2, and the coating system starts the coating process. After the coating is completed, the second electromagnetic reversing valve 13 loses power, and the pressure oil returns to the oil tank from the brake 9. The brake 9 brakes the pinch roller 2 under the action of the spring. In addition, the brake 9 can also be in a non-braking state under normal circumstances, and can be replaced by a brake in a braking state after pressurization.

[0058] In a preferred embodiment of the present application, the hydraulic braking device also includes a pressure reducing valve 12, which is arranged on the pipeline between the oil inlet P port of the second solenoid reversing valve 13 and the hydraulic pump output port. After the second solenoid reversing valve 13 is energized, the pressure oil enters the brake 9 through the pressure reducing valve 12 and the second solenoid reversing valve 13 in sequence. The pressure reducing valve 12 is used to adjust the unlocking pressure of the brake 9.

[0059] In a preferred embodiment of the present application, the braking device adopts an electromagnet brake. When the cotton bale begins to be coated, the electromagnet in the electromagnet brake is energized, so that the brake pad in the electromagnet brake is disengaged from the pinch roller 2, thereby releasing the brake.

[0060] like Figure 4 As shown, another preferred embodiment of the present application further provides a method for controlling a membrane hydraulic system, comprising the steps of:

[0061] S1. Process of actively feeding the film into the packing box: After the cotton is packed and formed in the packing box, the second electromagnetic directional valve 13 is energized to make the pressure oil enter the brake 9, thus releasing the brake of the pinch roller 2. The electro-hydraulic proportional speed regulating valve 5 is energized, and the energizing current is I1. The left position of the first electromagnetic directional valve 6 is energized. The high-pressure oil enters the hydraulic motor 8 through the electro-hydraulic proportional speed regulating valve 5 and the electromagnetic directional valve 6. The hydraulic motor 8 drives the pinch roller 2 to rotate for actively feeding the film. The rotational speed sensor 3 continuously detects the cumulative pulse number A1. When it is detected that A1 > A0, the electro-hydraulic proportional speed regulating valve 5 reduces the current to I0 to lower the rotational speed of the hydraulic motor 8. If the rotational speed sensor 3 detects that the rotational speed of the pinch roller 2 is n and n > n1, it is determined that the pinch roller 2 has successfully fed the packing film into the packer and the passive film feeding process is executed; if the rotational speed sensor 3 detects that the rotational speed of the pinch roller 2 is n and n < n1, it is determined that the pinch roller 2 fails to feed the packing film into the packer and the re-filming process is executed; where A0 represents the judgment threshold for whether the packing film enters the box during the normal film covering process, and n1 is the rotational speed threshold of the hydraulic motor 8 during active film feeding;

[0062] S2. Passive film feeding process: After the pinch roller 2 successfully feeds the packing film into the packer, the electro-hydraulic proportional speed regulating valve 5 is energized with the current I0. The active film feeding speed of the pinch roller 2 is n0. At this time, n0 < n2, and the film feeding speed of the pinch roller 2 is less than the film covering speed of the packer. The pinch roller 2 rotates passively under the drive of the packing film. The hydraulic motor 8 is in a negative load condition. The inlet flow rate Q0 of the hydraulic motor 8 is less than the required flow rate Q2 for the operation of the hydraulic motor 8. At this time, the first one-way valve 10 is opened, and the oil is replenished to the inlet of the hydraulic motor 8 through the first one-way valve 10 to prevent the hydraulic motor 8 from sucking air. At this time, the flow rate of the oil replenished through the one-way valve 10 is (Q2 - Q0). After the outlet flow rate Q of the hydraulic motor 8 subtracts the flow rate (Q2 - Q0) of the oil replenished by the first one-way valve 10, the excess flow rate opens the second one-way valve 11 and flows back to the oil tank. During this process, the flow rate Q0 passing through the electro-hydraulic proportional speed regulating valve 5 can not only supplement the internal leakage of the oil generated during the passive rotation of the hydraulic motor 8 but also enable the excess oil to flow back to the oil tank, thereby realizing the heat exchange of the oil during the passive rotation process and preventing the oil in the local loop from getting too hot. During the passive film feeding process, a tension force needs to be applied to the packing film to ensure the tightness of the bale after packing. In this embodiment, the back pressure regulating device is used to adjust the back pressure of the hydraulic motor 8 to change the magnitude of the tension force applied to the packing film. For example, by adjusting the spring compression amount of the balance valve 7 to adjust the back pressure of the hydraulic motor 8, and then changing the magnitude of the tension force applied to the packing film. For packing films with different ductility, the tension force applied to the packing film can be adjusted according to their ductility, or the tension force applied to the packing film can be changed according to the change in the ductility of the packing film caused by temperature changes, ensuring that the film covering quality and bale tightness of each cotton bale are optimal;

[0063] S3. Secondary film covering process: After the pinch roller 2 actively feeds the film, if the baler fails to successfully feed the packing film into the packing box, at this time, the film feeding speed of the pinch roller 2 is n0, the rotation speed sensor 3 detects the rotation speed n0, n0 < n1, the right position of the first electromagnetic directional valve 6 is energized, the hydraulic motor 8 rotates reversely to drive the pinch roller 2 to rotate reversely, recover the film actively fed by the pinch roller 2, the rotation speed sensor 3 detects the cumulative pulse value A2, when A2 > A1, the left position of the first electromagnetic directional valve 6 is energized, and continue to execute the process of actively feeding the film into the packing box. Among them, A1 is the cumulative number of pulses detected by the rotation speed sensor 3 during the forward film feeding process after the film covering starts.

[0064] S4. Post-film covering processing process: After the cotton bale is covered with film, the photoelectric sensor 4 detects the unique identification code on the packing film, controls the electro-hydraulic proportional speed regulating valve 5, the first electromagnetic directional valve 6 and the second electromagnetic directional valve 13 to lose power, and the braking device brakes the pinch roller 2. At this time, the pinch roller 2 stops feeding the film, the baler rotates normally, the packing film breaks at the interface, and the film covering is completed.

[0065] The control method provided by the above embodiment can actively feed the film before the packing film enters the packing box, passively feed the film after the packing film enters the packing box, brake and cut the film after the film feeding is completed, and perform secondary film feeding if the active film feeding into the packing box fails, increasing the film covering success rate. Among them, the flow rate Q1 corresponding to the given current I1 of the electro-hydraulic proportional speed regulating valve 5, the rotation speed n1 of the hydraulic motor 8 for active film feeding, the flow rate Q0 corresponding to the given current I0 of the electro-hydraulic proportional speed regulating valve 5, the rotation speed of the hydraulic motor 8 for active film feeding is n0, the rotation speed of the hydraulic motor 8 during passive film feeding after the packing film enters the box is n2, and the required flow rate for the rotation of the hydraulic motor 8 at this time is Q2, where n2 > n1 > n0, Q2 > Q1 > Q0. The starting state of film covering is that the hydraulic motor 8 drives the pinch roller 2 to actively feed the film. During the active film feeding process, when the rotation speed sensor 3 detects that the cumulative pulse value is A0, it switches to passive film feeding.

[0066] Preferably, if the secondary film covering process fails, a film covering failure is prompted on the display screen interface. At this time, the driver can stop the vehicle for inspection, so that even if the film covering fails, it will not cause the accumulation or entanglement of the packing film.

[0067] Another preferred embodiment of the present application also provides a film covering system for a cotton picker, including a baler and the above-mentioned film covering hydraulic system.

[0068] Another preferred embodiment of the application also provides a cotton picker, including the above-mentioned film covering system for a cotton picker.

[0069] The above are only the preferred embodiments of the present application and are not used to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A membrane hydraulic system, characterized in that: The invention comprises a packaging film (1), a pinch roller (2), a speed sensor (3), a photoelectric sensor (4), an electric proportional speed regulating valve (5), a first electromagnetic reversing valve (6), a back pressure regulating device, a hydraulic motor (8), a braking device, a first one-way valve (10), a second one-way valve (11), and a second electromagnetic reversing valve (13), wherein: The oil inlet port P of the first electromagnetic reversing valve (6) is connected to the electric proportional speed regulating valve (5) and the output port of the hydraulic pump in sequence, the working port A is connected to the back pressure regulating device and the hydraulic motor (8) in sequence, the working port B is connected to the other input port of the hydraulic motor (8) through a pipeline, and the oil return port T is connected to the working port B through a first one-way valve (10) on the one hand, and to the oil tank through a second one-way valve (11) on the other hand; The output end of the hydraulic motor (8) is connected to the pinch roller (2) through a transmission shaft, driving the pinch roller (2) to rotate and feed the packaging film (1) into the packaging box; The braking device is arranged relative to the transmission shaft and is used to brake the pinch roller (2); The rotation speed sensor (3) is used to measure the rotation speed of the pinch roller (2), measure the cumulative number of pulses, and convert the cumulative number of pulses into the length of the delivered or recovered packaging film (1); The photoelectric sensor (4) is used to detect the identification code on the packaging film and to determine whether the film feeding is completed.

2. The membrane hydraulic system according to claim 1, characterized in that: The back pressure regulating device comprises a balancing valve (7), one end of the balancing valve (7) is connected to the hydraulic motor (8), and the other end is connected to the working port A of the first electromagnetic reversing valve (6), and the hydraulic control port K of the balancing valve (7) is connected to the working port B of the first electromagnetic reversing valve (6).

3. The membrane hydraulic system according to claim 1, characterized in that: The back pressure regulating device comprises an electric proportional overflow valve (14) and a third one-way valve (15) arranged in parallel.

4. The membrane hydraulic system according to claim 1, characterized in that: The braking device adopts a hydraulic braking device, which includes a hydraulic brake (9) and a second electromagnetic reversing valve (13). The oil inlet P of the second electromagnetic reversing valve (13) is connected to the output port of the hydraulic pump through a pipeline, the oil return port T is connected to the oil tank, and the working port A is connected to the hydraulic brake (9).

5. The membrane hydraulic system according to claim 4, characterized in that: The hydraulic brake device further comprises a pressure reducing valve (12) which is arranged on a pipeline between the oil inlet port P of the second electromagnetic reversing valve (13) and the output port of the hydraulic pump.

6. The membrane-coated hydraulic system according to claim 1, characterized in that: The braking device adopts an electromagnetic brake.

7. A control method for a membrane hydraulic system, based on the membrane hydraulic system according to any one of claims 1 to 6, characterized in that: Including steps: Process of actively feeding the film into the packing box: After the cotton is packed and formed in the packing box, the braking device is in the state of brake release, the electro-hydraulic proportional speed control valve (5) is powered on, and the power-on current is I1. The left position of the first electromagnetic directional control valve (6) is powered on. High-pressure oil enters the hydraulic motor (8) through the electro-hydraulic proportional speed control valve (5) and the first electromagnetic directional control valve (6). The hydraulic motor (8) drives the pinch roller (2) to rotate for actively feeding the film. The rotational speed sensor (3) real-time detects the cumulative pulse number A1. When it is detected that A1 > A0, the electro-hydraulic proportional speed control valve (5) reduces the current to I0 to reduce the rotational speed of the hydraulic motor (8). If the rotational speed sensor (3) detects that the rotational speed of the pinch roller (2) is n and n > n1, it is determined that the pinch roller (2) has successfully fed the packing film into the packer and the passive film feeding process is executed; if the rotational speed sensor (3) detects that the rotational speed of the pinch roller (2) is n and n < n1, it is determined that the pinch roller (2) fails to feed the packing film into the packer and the re-filming process is executed; where A0 represents the judgment threshold for whether the packing film enters the box during the normal film covering process, and n1 is the rotational speed threshold of the hydraulic motor (8) during active film feeding; Passive film feeding process: After the pinch roller (2) successfully feeds the packing film into the packer, the electro-hydraulic proportional speed control valve (5) has a power-on current of I0, and the active film feeding speed of the pinch roller (2) is n0. At this time, n0 < n2, and n2 is the rotational speed of the hydraulic motor (8) during passive film feeding after the packing film enters the box. The film feeding speed of the pinch roller (2) is less than the film covering speed of the packer. The pinch roller (2) rotates passively under the drive of the packing film. The hydraulic motor (8) is in a negative load condition. The inlet flow rate Q0 of the hydraulic motor (8) is less than the operating demand flow rate Q2 of the hydraulic motor (8). At this time, the first check valve (10) opens, and the oil is replenished to the inlet of the hydraulic motor (8) through the first check valve (10). After subtracting the oil replenishment flow rate of the first check valve (10) from the outlet flow rate Q2 of the hydraulic motor (8), the excess flow rate opens the second check valve (11) and flows back to the oil tank. During the passive film feeding process, the back pressure of the hydraulic motor (8) is adjusted by the back pressure regulating device to change the magnitude of the tension applied to the packing film; Second film covering process: After the pinch roller (2) actively feeds the film, if the packer fails to successfully feed the packing film into the packing box, at this time the film feeding speed of the pinch roller (2) is n0, and the rotational speed n0 detected by the rotational speed sensor (3), n0 < n1. The right position of the first electromagnetic directional control valve (6) is powered on, and the hydraulic motor (8) rotates reversely to drive the pinch roller (2) to rotate reversely to recover the film actively sent out by the pinch roller (2). The rotational speed sensor (3) detects the cumulative pulse value A2. When A2 > A1, the left position of the first electromagnetic directional control valve (6) is powered on, and the process of actively feeding the film into the packing box is continued; Post-film coating process: After the cotton bale is coated, the photoelectric sensor (4) detects the unique identification code on the packaging film, controls the electric proportional speed control valve (5), the first electromagnetic reversing valve (6) and the second electromagnetic reversing valve (13) to lose power, and the braking device brakes the pinch roller (2). At this time, the pinch roller (2) stops feeding the film, the packaging device rotates normally, the packaging film is disconnected at the interface, and the coating is completed.

8. The control method of the membrane hydraulic system according to claim 7, characterized in that: If the secondary lamination process fails, a lamination failure message will be displayed on the display screen.

9. A cotton picker film covering system, characterized in that: The invention comprises a packer and a film covering hydraulic system according to any one of claims 1 to 6.

10. A cotton picker, characterized in that: It includes the cotton picker covering system as described in claim 9.

Images