A garbage truck hydraulic system, a garbage truck and a hydraulic control method

Abstract

This invention provides a hydraulic system for a garbage truck, a garbage truck, and a control method, relating to the field of garbage trucks. The hydraulic system includes an oil tank, an oil pump, a main inlet oil circuit, a main return oil circuit, a first directional valve, a second directional valve, a third directional valve, a fourth directional valve, outrigger oil circuits, a scraper oil circuit, a sliding plate oil circuit, a tipping barrel oil circuit, and a bidirectional electromagnetic directional valve. The bidirectional electromagnetic directional valve is located between the first directional valve and the rodless chamber of the outrigger cylinder. Driven by the oil pump, the scraper cylinder, sliding plate cylinder, and tipping barrel cylinder perform combined actions. When any one of the scraper cylinder, sliding plate cylinder, or tipping barrel cylinder performs a combined extension / retraction action, the outrigger cylinder remains locked. By providing the bidirectional electromagnetic directional valve, internal leakage of the first directional valve can be prevented when other oil circuits are in combined action, thereby preventing the outrigger cylinder from operating when the first directional valve is in the neutral position with pressure buildup, thus preventing the outriggers from falling off and ensuring driving safety.

Description

Technical Field

[0001] This invention relates to the field of hydraulic control system technology for garbage trucks, and more specifically, to a hydraulic system for garbage trucks, a garbage truck, and a hydraulic control method. Background Technology

[0002] Currently, self-loading and unloading garbage trucks are mainly used for collecting and transporting domestic waste in urban residential areas, streets, and farmers' markets. Due to their small overall width, strong loading capacity, good adaptability, and high equipment demand, self-loading and unloading garbage trucks are used for various purposes. During the loading process of self-loading and unloading garbage trucks, the compaction mechanism performs a compaction cycle: that is, the sliding plate moves forward → the scraper closes → the sliding plate moves backward → the scraper opens in a cycle, while the feeding mechanism performs the lifting and unloading action.

[0003] However, in related technologies, the outriggers of garbage trucks frequently extend or fall off during compaction and loading operations, posing a significant safety hazard to garbage truck transportation. Summary of the Invention

[0004] This invention provides a hydraulic system for a garbage truck, a garbage truck, and a hydraulic control method, which can ensure that the outrigger cylinders do not extend when other mechanisms of the garbage truck, except for the outriggers, are working, thereby ensuring driving safety and improving reliability.

[0005] The embodiments of the present invention can be implemented as follows: An embodiment of the present invention provides a hydraulic system for a garbage truck, comprising: an oil tank, an oil pump, a main oil inlet circuit, a main oil return circuit, a first reversing valve, a second reversing valve, a third reversing valve, a fourth reversing valve, outrigger oil circuits, scraper oil circuits, sliding plate oil circuits, tipping bucket oil circuits, and a two-way electromagnetic reversing valve; the oil outlet of the oil tank is connected to the oil inlet of the oil pump, the oil outlet of the oil pump is connected to the main oil inlet circuit, and the oil return port of the oil tank is connected to the main oil return circuit; The first reversing valve, the second reversing valve, the third reversing valve, and the fourth reversing valve are all connected in parallel between the main oil inlet circuit and the main oil return circuit; The outrigger cylinder is installed in the outrigger oil circuit. The first reversing valve enables one of the rod chamber and the rodless chamber of the outrigger cylinder to be connected to the main oil inlet circuit, and the other to be connected to the main oil return circuit. The scraper cylinder is installed in the scraper oil circuit. The second reversing valve enables one of the rod chamber and the rodless chamber of the scraper cylinder to be connected to the main oil inlet circuit and the other to be connected to the main oil return circuit. The slide plate cylinder is installed in the slide plate oil circuit. The third directional valve enables one of the rod chamber and the rodless chamber of the slide plate cylinder to be connected to the main oil inlet circuit, and the other to be connected to the main oil return circuit. The tipping cylinder is installed in the tipping oil circuit. The fourth directional valve enables one of the rod chamber and the rodless chamber of the tipping cylinder to be connected to the main oil inlet circuit, and the other to be connected to the return oil line. The bidirectional electromagnetic reversing valve is located between the first reversing valve and the rodless chamber of the outrigger cylinder; under the drive of the oil pump, the scraper cylinder, the sliding plate cylinder, and the tipping cylinder perform a combined action; when any one of the scraper cylinder, the sliding plate cylinder, and the tipping cylinder performs a combined extension and retraction action, the outrigger cylinder remains locked.

[0006] In an optional embodiment, the bidirectional solenoid valve has a left position and a right position. When the bidirectional solenoid valve is in the left position, both ports of the bidirectional solenoid valve are energized and connected; when the bidirectional solenoid valve is in the right position, the bidirectional solenoid valve is de-energized and cut off in both directions.

[0007] In an optional embodiment, the first reversing valve is an O-type three-position four-way reversing valve with ports T1, P1, A1, and B1. Port P1 is connected to the main oil inlet circuit, port T1 is connected to the main oil return circuit, and ports A1 and B1 are respectively used to connect to the rodless chamber and the rod chamber of the outrigger cylinder. When the first reversing valve is in the first state, port P1 and port A1 are connected, and port B1 and port T1 are connected. When the first reversing valve is in the second state, port P1 is connected to port B1, and port A1 is connected to port T1. When the first reversing valve is in the third state, port P1 is not connected to port A1 and port B1, and port T1 is not connected to port A1 and port B1. When the bidirectional electromagnetic reversing valve is in the right position, the first reversing valve is in the third state.

[0008] In an optional embodiment, the second, third, and fourth directional valves are all three-position four-way directional valves. The second directional valve has ports T2, P2, A2, and B2; the third directional valve has ports T3, P3, A3, and B3; and the fourth directional valve has ports T4, P4, A4, and B4. Ports P2, P3, and P4 are respectively connected to the main oil inlet circuit, and ports T2, T3, and T4 are respectively connected to the main oil return circuit. Ports A2, A3, A4, and B2, B3, and B4 are respectively used to connect the rodless chamber and the rod chamber of the scraper cylinder, the sliding plate cylinder, and the tipping drum cylinder. When the second reversing valve is in the first state, port P2 and port A2 are connected, and port B2 and port T2 are connected. When the second reversing valve is in the second state, port P2 is connected to port B2, and port A2 is connected to port T2. When the third reversing valve is in the first state, port P3 and port A3 are connected, and port B3 and port T3 are connected. When the third reversing valve is in the second state, port P3 is connected to port B3, and port A3 is connected to port T3.

[0009] When the fourth reversing valve is in the first state, port P4 and port A4 are connected, and port B4 and port T4 are connected. When the fourth reversing valve is in the second state, port P4 is connected to port B4, and port A4 is connected to port T4.

[0010] When any one of the second reversing valve, the third reversing valve, or the fourth reversing valve is in the first state or the second state, the first reversing valve is in the third state.

[0011] In an optional embodiment, the garbage truck hydraulic system further includes a first hydraulic lock, which is disposed between the outrigger cylinder and the first directional valve.

[0012] In an optional embodiment, the garbage truck hydraulic system further includes a lifting oil circuit, which is connected in parallel with the outrigger oil circuit. A lifting cylinder is disposed in the lifting oil circuit. The first reversing valve enables one of the rod-side chamber and the rodless chamber of the lifting cylinder to be connected to the main inlet oil circuit and the other to be connected to the main return oil circuit. A balance valve is disposed between the lifting cylinder and the first reversing valve.

[0013] In an optional embodiment, the garbage truck hydraulic system further includes a second hydraulic lock, which is disposed between the second directional valve and the scraper cylinder; And / or, the second directional valve is a Y-type three-position four-way directional valve. When the second directional valve is in the third state, port P2 is open, and ports A2 and B2 are both connected to port T2; and / or, The garbage truck hydraulic system also includes a third hydraulic lock, which is located between the third directional valve and the sliding plate cylinder; And / or, the third directional valve is a Y-type three-position four-way directional valve. When the third directional valve is in the third state, port P3 is disconnected, and ports A3 and B3 are both connected to port T3; and / or, The garbage truck hydraulic system also includes a fourth hydraulic lock, which is located between the fourth directional valve and the tipping cylinder; And / or, the fourth directional valve is a Y-type three-position four-way directional valve. When the fourth directional valve is in the third state, port P4 is disconnected, and ports A4 and B4 are both connected to port T4.

[0014] In an optional embodiment, the garbage truck hydraulic system further includes a first overflow valve, which is disposed between the main oil inlet circuit and the main oil return circuit; and / or, The garbage truck hydraulic system also includes a fifth directional valve, which is located between the main oil inlet circuit and the main oil return circuit.

[0015] In an optional embodiment, the garbage truck hydraulic system further includes a second overflow valve, one end of which is connected to the oil return port of the oil tank, and the other end of which is connected to the rodless chamber of the scraper cylinder; and / or, The garbage truck hydraulic system also includes a third overflow valve, one end of which is connected to the oil return port of the oil tank, and the other end of which is connected to the rodless chamber of the sliding plate cylinder.

[0016] Embodiments of the present invention also provide a garbage truck, including a vehicle body and a garbage truck hydraulic system as described in any of the above embodiments, wherein the garbage truck hydraulic system is disposed on the vehicle body.

[0017] In an optional embodiment, the garbage truck hydraulic system further includes a lifting oil circuit, which is connected in parallel with the outrigger oil circuit. A lifting cylinder is disposed in the lifting oil circuit. The first reversing valve enables one of the rod chamber and the rodless chamber of the lifting cylinder to be connected to the main inlet oil circuit and the other to be connected to the main return oil circuit. The vehicle body includes a garbage bin, a subframe, and outriggers. The lifting cylinder is connected between the subframe and the garbage bin. The subframe is equipped with a proximity switch. When the first reversing valve is connected to the main oil inlet circuit, the bidirectional electromagnetic reversing valve is energized, the outrigger oil circuit is first connected, the outrigger cylinder extends and drives the outrigger to extend, and after the outrigger extends to the position, the lifting oil circuit is connected, the lifting cylinder extends and drives the garbage bin to lift. When the first reversing valve is connected to the main return oil circuit, the lifting oil circuit is connected first, the lifting cylinder retracts and drives the garbage bin to descend; when the garbage bin descends to contact the subframe, the proximity switch is energized, which controls the bidirectional electromagnetic reversing valve to be energized, the outrigger oil circuit is connected, the outrigger cylinder retracts and drives the outrigger to retract.

[0018] Embodiments of the present invention also provide a hydraulic control method for a garbage truck, applied to the garbage truck hydraulic system described in any of the above embodiments or the garbage truck described in the above embodiments, the control method comprising: The hydraulic oil is pumped from the oil tank to the main oil inlet circuit by the oil pump. Control at least one of the first reversing valve, the second reversing valve, the third reversing valve, and the fourth reversing valve to activate the main oil inlet circuit to connect with the rod-side or rodless chamber of the corresponding outrigger cylinder, the scraper cylinder, the sliding plate cylinder, or the tipping drum cylinder, while the main oil return circuit connects with the corresponding rodless or rod-side chamber. When the scraper cylinder, the sliding plate cylinder, or the tipping cylinder performs a combined extension and retraction action, that is, when at least one of the scraper oil circuit, the sliding plate oil circuit, and the tipping oil circuit is connected to the main inlet oil circuit and the main return oil circuit, the first reversing valve is controlled to switch to the third state, and the bidirectional electromagnetic reversing valve is controlled to be in the right position, so as to lock the rodless chamber of the outrigger cylinder, thereby preventing the outrigger cylinder from extending.

[0019] In an optional implementation, the control method further includes: when the outrigger cylinder needs to be activated, controlling the bidirectional electromagnetic reversing valve to be in the left position, and controlling the first reversing valve to switch to the first state or the second state to realize the extension or retraction of the outrigger cylinder.

[0020] In an optional embodiment, the garbage truck hydraulic system further includes a lifting oil circuit, which is connected in parallel with the outrigger oil circuit. A lifting cylinder is disposed in the lifting oil circuit. The first reversing valve enables one of the rod-side and rodless sides of the lifting cylinder to be connected to the main inlet oil circuit, and the other to be connected to the main return oil circuit. The vehicle body includes a garbage bin, a subframe, and outriggers. The lifting cylinder is connected between the subframe and the garbage bin. The subframe is equipped with a proximity switch. The proximity switch is used to detect the relative position of the garbage bin and the subframe. The control method further includes: When the first reversing valve is switched to be connected to the main oil inlet circuit, the bidirectional solenoid reversing valve is energized, so that the bidirectional solenoid reversing valve is in a state of being energized and connected at both ports, so that the outrigger oil circuit is opened first, driving the outrigger cylinder to extend, thereby driving the outrigger to extend; after the outrigger is extended to the position, the lifting oil circuit is opened, driving the lifting cylinder to extend and driving the garbage bin to lift. When the first reversing valve is connected to the main return oil circuit, the lifting oil circuit is connected first, the lifting cylinder retracts and drives the garbage bin to descend; when the garbage bin descends to contact the subframe, the proximity switch is detected and the bidirectional electromagnetic reversing valve is energized, so that the outrigger oil circuit is connected, driving the outrigger cylinder to retract and driving the outrigger to retract.

[0021] The beneficial effects of the garbage truck hydraulic system, garbage truck, and hydraulic control method according to embodiments of the present invention include, for example: The hydraulic system of this garbage truck includes an oil tank, an oil pump, a main inlet oil circuit, a main return oil circuit, a first directional valve, a second directional valve, a third directional valve, a fourth directional valve, outrigger oil circuits, scraper oil circuits, a sliding plate oil circuit, a tipping bucket oil circuit, and a two-way solenoid directional valve. The outlet of the oil tank is connected to the suction port of the oil pump, the outlet of the oil pump is connected to the main inlet oil circuit, and the return port of the oil tank is connected to the main return oil circuit. The first, second, third, and fourth directional valves are all connected in parallel between the main inlet oil circuit and the main return oil circuit. The outrigger cylinders are located in the outrigger oil circuits. The first directional valve enables one of the rod-side and rodless sides of the outrigger cylinder to be connected to the main inlet oil circuit, and the other to the main return oil circuit. The scraper cylinders are located in the scraper oil circuits. The second directional valve enables the scraper cylinder to... One of the rod-side chamber and the rodless chamber is connected to the main oil inlet circuit, and the other is connected to the main oil return circuit; the sliding plate cylinder is located in the sliding plate oil circuit, and the third directional valve enables one of the rod-side chamber and the rodless chamber of the sliding plate cylinder to be connected to the main oil inlet circuit, and the other to the main oil return circuit; the tipping cylinder is located in the tipping cylinder oil circuit, and the fourth directional valve enables one of the rod-side chamber and the rodless chamber of the tipping cylinder to be connected to the main oil inlet circuit, and the other to the oil return circuit; the bidirectional electromagnetic directional valve is located between the first directional valve and the rodless chamber of the outrigger cylinder; under the drive of the oil pump, the scraper cylinder, the sliding plate cylinder, and the tipping cylinder perform compound actions, and when any one of the scraper cylinder, the sliding plate cylinder, and the tipping cylinder performs a compound extension and retraction action, the outrigger cylinder remains locked. When a garbage truck performs a compaction and pressing operation, because the directional valve is a spool valve, even when the first directional valve is in the neutral position with pressure buildup (i.e., the outrigger oil circuit is not connected to the main inlet and return oil circuits), oil leakage may still occur, causing the outrigger cylinders to actuate and the outriggers to detach. In severe cases, this can affect driving safety. By installing a bidirectional electromagnetic directional valve, leakage in the outrigger oil circuit can be prevented even when the first directional valve is in the neutral position with pressure buildup. This prevents the outrigger cylinders from extending even when the outrigger oil circuit is not connected to the main inlet and return oil circuits, thus preventing the outriggers from detaching and ensuring the driving safety and reliability of the garbage truck. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a control principle diagram of a prior art hydraulic system provided in an embodiment of the present invention; Figure 2 This is a control principle diagram of a hydraulic system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram comparing the scraping working pressure of the scraper when the electromagnetic reversing valve is in an O-type and a Y-type position, as provided in an embodiment of the present invention.

[0024] Icons: 1000 - Garbage truck hydraulic system; 100 - Oil tank; 200 - Oil pump; 310 - Main oil inlet circuit; 320 - Main oil return circuit; 410 - Outrigger circuit; 411 - Two-way solenoid directional valve; 412 - First hydraulic lock; 420 - Lifting circuit; 421 - Balance valve; 430 - Scraper circuit; 431 - Second hydraulic lock; 440 - Slide plate circuit; 441 - Third hydraulic lock; 450 - Tipping Oil circuit for drum; 451-Fourth hydraulic lock; 510-First directional valve; 520-Second directional valve; 530-Third directional valve; 540-Fourth directional valve; 610-Outrigger cylinder; 620-Lifting cylinder; 630-Scraper cylinder; 640-Slide plate cylinder; 650-Drum tipping cylinder; 700-First relief valve; 810-Second relief valve; 820-Third relief valve; 900-Fifth directional valve; In the existing technology: 10-Main oil inlet circuit; 20-Main oil return circuit; 31-Outrigger circuit; 32-Lifting circuit; 33-Scraper circuit; 34-Slide plate circuit; 35-Tilting circuit; 11-First directional valve; 12-Second directional valve; 13-Third directional valve; 14-One-way solenoid directional valve; 15-Fourth directional valve; 40-Hydraulic lock; 51-Outrigger cylinder; 52-Lifting cylinder; 53-Scraper cylinder; 54-Slide plate cylinder; 55-Tilting cylinder; 60-Oil tank. Detailed Implementation To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0028] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0029] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0030] Currently, self-loading and unloading garbage trucks are mainly used for collecting domestic waste from urban residential areas, streets, and farmers' markets. Due to their narrow overall width, high loading capacity, and good adaptability, they have high equipment requirements. During the loading process of self-loading and unloading garbage trucks, the compaction mechanism performs a compaction cycle: the sliding plate moves forward → the scraper closes → the sliding plate moves backward → the scraper opens, while the feeding mechanism performs the lifting and unloading action. However, in related technologies, during the compaction and feeding actions, the outriggers frequently extend or fall off, posing a significant safety hazard to garbage truck transportation operations.

[0031] Figure 1 This is a control principle diagram of a prior art hydraulic system provided in an embodiment of the present invention. (See diagram for example.) Figure 1As shown, during the compaction cycle and the pressurization of the loading mechanism, because the valve core of the multi-way valve is mostly a spool valve structure, leakage will occur when the cylinder is pressurized in the middle position. The leaking oil will pass through the reversing valve to the hydraulic lock of the outrigger cylinder. Usually, a reversing valve is added between the multi-way valve and the hydraulic lock of the outrigger cylinder in the outrigger oil circuit. This additional reversing valve is used to switch the sequence of action of the outrigger cylinder and the lifting cylinder. The principle of this additional reversing valve is normally open, and the oil flow direction is unidirectional, only inflow and no outflow. As the cumulative number of upper structure actions increases, the pressure of the oil passing through the reversing valve eventually rises to the opening pressure of the hydraulic lock, which may cause the outrigger cylinder to extend or the outrigger to fall off.

[0032] Based on this, please refer to Figure 2 The garbage truck hydraulic system 1000 provided in the embodiments of the present invention can solve the aforementioned technical problems. This garbage truck hydraulic system 1000 ensures that the outrigger cylinders 610 do not extend while other mechanisms of the garbage truck, excluding the outriggers, are operating, thus ensuring driving safety and improving reliability. This garbage truck hydraulic system 1000 is applied to garbage trucks, and garbage trucks equipped with this system have the same functions as described above, which will not be elaborated further here.

[0033] The garbage truck in this embodiment includes a vehicle body and a garbage truck hydraulic system 1000, which is installed on the vehicle body. The vehicle body is equipped with a garbage bin, a compaction mechanism, a feeding mechanism, and outriggers. The feeding mechanism is located behind the garbage bin and is used to lift and dump garbage bins or hoppers into the garbage bin. The compaction mechanism is located above the garbage bin and is used to compress and circulate the garbage inside. The outriggers are located below the garbage bin and are used to provide auxiliary support for the garbage truck during unloading. The feeding mechanism is connected to a tipping cylinder 650. The tipping cylinder 650 extends to perform the feeding action; the tipping cylinder 650 retracts to perform the unloading action. The compaction mechanism includes a scraper assembly and a sliding plate assembly. A scraper cylinder 630 is connected to the scraper assembly, and a sliding plate cylinder 640 is connected to the sliding plate assembly. The sliding plate assembly is connected to the scraper assembly, and the sliding plate assembly is used to move the scraper assembly. When the compaction mechanism is working, the sliding plate assembly first moves forward to above the garbage bin's feeding port, and the scraper assembly performs a scraping action. The scraper rotates from the highest position to the lowest position and compresses the bulk garbage fed by the tipping mechanism once. The scraper assembly remains stationary at the lowest position, and the sliding plate assembly moves backward, driving the scraper assembly to move towards the front of the garbage bin. The scraper assembly performs a second horizontal compression of the garbage after the first compression. After the compression is completed, the scraper assembly opens to allow for the next garbage compression action.

[0034] Of course, garbage trucks may also include other structures to achieve multiple functions, depending on the actual use, and are not limited here.

[0035] The following is a detailed introduction to the hydraulic system of the garbage truck 1000.

[0036] Figure 2 This is a control principle diagram of the hydraulic system 1000 for a garbage truck provided in an embodiment of the present invention. Figure 2 As shown, the hydraulic system 1000 of the garbage truck in this embodiment includes an oil tank 100, an oil pump 200, a main oil inlet circuit 310, a main oil return circuit 320, a first reversing valve 510, a second reversing valve 520, a third reversing valve 530, a fourth reversing valve 540, an outrigger oil circuit 410, a scraper oil circuit 430, a sliding plate oil circuit 440, a tipping barrel oil circuit 450, and a two-way electromagnetic reversing valve 411. The oil outlet of the oil tank 100 is connected to the oil suction port of the oil pump 200, the oil outlet of the oil pump 200 is connected to the main oil inlet circuit 310, and the oil return port of the oil tank 100 is connected to the main oil return circuit 320; the first reversing valve 510, the second reversing valve 520, the third reversing valve 530, and the fourth reversing valve 540 are all connected in parallel between the main oil inlet circuit 310 and the main oil return circuit 320; the outrigger cylinder 610 is located in the outrigger oil circuit 410; the scraper cylinder 630 is located in the scraper oil circuit 430, and the second reversing valve 520 enables one of the rod chamber and the rodless chamber of the scraper cylinder 630 to be connected to the main oil inlet circuit 310, and the other to be connected to the main oil return circuit 320; the slide plate cylinder 640 is located in the slide plate oil circuit 440, and the third reversing valve 530 enables the slide plate cylinder to be connected to the slide plate oil circuit 440. One of the rod-side chamber and the rodless chamber of cylinder 640 is connected to the main oil inlet circuit 310, and the other is connected to the main oil return circuit 320; the tipping cylinder 650 is located in the tipping oil circuit 450, and the fourth directional valve 540 enables one of the rod-side chamber and the rodless chamber of tipping cylinder 650 to be connected to the main oil inlet circuit 310, and the other to be connected to the oil return circuit; the bidirectional electromagnetic directional valve 411 is located between the first directional valve 510 and the rodless chamber of the outrigger cylinder 610; under the drive of the oil pump 200, the scraper cylinder 630, the sliding plate cylinder 640, and the tipping cylinder 650 perform compound actions, and when any one of the scraper cylinder 630, the sliding plate cylinder 640, and the tipping cylinder 650 performs a compound extension and retraction action, the outrigger cylinder 610 remains locked. The first directional valve 510 and the two-way solenoid directional valve 411 can also connect one of the rod-side chamber and the rodless chamber of the outrigger cylinder 610 to the main inlet oil circuit 310, and the other to the main return oil circuit 320. Multiple cylinders can be controlled simultaneously through one oil tank 100 and one oil pump 200, reducing the number of power components in the garbage truck hydraulic system 1000 and saving costs. Of course, multiple additional branches connected in parallel with the circuit of the first directional valve 510 can be added to achieve control of multiple actions through one oil tank 100 and one oil pump 200; the number of parallel branches is not limited here.

[0037] In the prior art, reference Figure 1When the garbage truck performs the compaction and filling combined operation, because the reversing valve is a spool valve structure, even if the first reversing valve 11 is in the neutral position with pressure buildup, that is, when the outrigger oil circuit 31 is not connected to the main inlet oil circuit 10 and the main return oil circuit 20, there may still be oil leakage. With the frequent operation of the compaction mechanism and the feeding mechanism, the pressure at the port of the one-way solenoid reversing valve 14 increases. When the pressure rises to the point where the hydraulic lock 40 is opened at port A, the hydraulic lock connected to the rodless chamber of the outrigger cylinder 51 is forced to open, causing the oil flow direction of the outrigger cylinder 51 to be only in and not out, causing the outrigger cylinder 51 to extend, resulting in the phenomenon of the outrigger falling off. In severe cases, it may affect driving safety.

[0038] In this invention, reference Figure 2 By setting a bidirectional electromagnetic reversing valve 411, even if hydraulic oil leakage occurs due to pressure buildup in the multi-way valve when the first reversing valve 510 is in the neutral position, the hydraulic lock connecting the rodless and rod-side chambers of the outrigger cylinder 610 cannot be opened because the oil flow direction between the bidirectional electromagnetic reversing valve 411 and the rodless chamber of the outrigger cylinder 610 is non-in-exit. This prevents the outrigger cylinder 610 from extending when the outrigger oil circuit 410 is not connected to the main inlet oil circuit 310 and the main return oil circuit 320, thus preventing the outrigger from falling off and ensuring the driving safety and reliability of the garbage truck.

[0039] Specifically, the bidirectional solenoid valve 411 in this embodiment has a left position and a right position. When the bidirectional solenoid valve 411 is in the left position, both ports of the bidirectional solenoid valve are energized and connected; when the bidirectional solenoid valve 411 is in the right position, the bidirectional solenoid valve is de-energized and cut off in both directions.

[0040] Specifically, please refer to Figure 2 In this embodiment, the first directional valve 510 is an O-type three-position four-way directional valve with ports T1, P1, A1, and B1. Port P1 is connected to the main oil inlet circuit 310, port T1 is connected to the main oil return circuit 320, and ports A1 and B1 are used to connect to the rodless chamber and rod chamber of the outrigger cylinder 610, respectively. When the first reversing valve 510 is in the first state, port P1 and port A1 are connected, and port B1 and port T1 are connected. When the first directional valve 510 is in the second state, port P1 is connected to port B1, and port A1 is connected to port T1. When the first directional valve 510 is in the third state, port P1 is not connected to ports A1 and B1, and port T1 is not connected to ports A1 and B1. When the bidirectional solenoid directional valve 411 is in the right position, the first directional valve 510 is in the third state.

[0041] The first directional valve 510 adopts an O-type three-position four-way valve. In the O-type neutral position, the oil ports are not interconnected, the garbage truck hydraulic system 1000 maintains pressure, and the oil in the two chambers of the outrigger cylinder 610 or lifting cylinder 620 is sealed and locked. The O-type neutral position function can maintain high-precision positioning when stopped. Moreover, the use of an O-type three-position four-way valve can also ensure a smoother transition from standstill to start-up during the switching process of the first directional valve 510, reducing the impact and vibration during startup. Of course, other types of directional valves can also be used for the first directional valve 510 depending on the actual working conditions, and are not limited here.

[0042] In addition, please continue to refer to Figure 2 To facilitate control over the sequence of actions of the lifting cylinder 620 and the outrigger cylinder 610, thereby improving safety during garbage truck operation, the garbage truck hydraulic system 1000 in this embodiment further includes a lifting oil circuit 420. The lifting oil circuit 420 is connected in parallel with the outrigger oil circuit 410. The lifting cylinder 620 is located in the lifting oil circuit 420. A first directional valve 510 enables one of the rod-side and rodless chambers of the lifting cylinder 620 to be connected to the main inlet oil circuit 310, and the other to be connected to the main return oil circuit 320. In this embodiment, the connection between the outrigger oil circuit 410 and the lifting oil circuit 420 and the main inlet oil circuit 310 and the main return oil circuit 320 is controlled by the first directional valve 510. When the first reversing valve 510 is in the first state and the bidirectional solenoid reversing valve 411 is energized and in the left-hand conducting position, the rodless chamber of the outrigger cylinder 610 and the rodless chamber of the lifting cylinder 620 are connected to the main oil inlet circuit 310, and the rod chamber of the outrigger cylinder 610 and the rod chamber of the lifting cylinder 620 are connected to the main return oil circuit 320. Due to the significant difference between the weight of the garbage bin and the outriggers, the outrigger cylinder 610 will extend first, and the outriggers will support the ground first. Then, the lifting cylinder 620 will lift the garbage bin, thereby ensuring that the garbage bin can be safely lifted and unloaded. When the first directional valve 510 is in the second state, the rod chamber of the lifting cylinder 620 is connected to the main oil inlet circuit 310, and the rodless chamber of the lifting cylinder 620 is connected to the main return oil circuit 320. The garbage bin descends to its position first. After the proximity switch is energized, it controls the bidirectional solenoid directional valve 411 to be energized. The bidirectional solenoid directional valve 411 is in the left position. The rod chamber of the outrigger cylinder 610 is connected to the main oil inlet circuit 310, and the rodless chamber of the outrigger cylinder 610 is connected to the main return oil circuit 320. The outrigger cylinder 610 retracts to realize the retraction of the outrigger.

[0043] Of course, the lifting oil circuit 420 and the outrigger oil circuit 410 can also be controlled separately by different directional valves to be connected to the main oil inlet circuit 310 and the main oil return circuit 320, which is not limited here.

[0044] To balance pressure or flow differences in the garbage truck's hydraulic system 1000 and control the movement of the lifting cylinder 620 within the system, ensuring safety, a balance valve 421 is installed between the lifting cylinder 620 and the first directional valve 510. By installing the balance valve 421, back pressure is applied during the descent to prevent the lifting cylinder 620 from descending too quickly due to gravity, thus ensuring smooth movement. The load pressure provided by the balance valve 421 allows for a stable and controllable garbage descent speed, and the balance valve 421 also functions as an explosion-proof valve.

[0045] To maintain the outrigger position and prevent accidental movement of the outrigger due to external loads or gravity in the hydraulic circuit, please refer to [link to relevant documentation]. Figure 2 In this embodiment, the garbage truck hydraulic system 1000 also includes a first hydraulic lock 412, which is installed between the outrigger cylinder 610 and the first directional valve 510. The first hydraulic lock 412 forms an interlock structure through two one-way valves. When the first directional valve 510 is in the neutral position, it blocks the flow of hydraulic fluid, allowing the outrigger cylinder 610 to remain stationary under external load. During operation, in the event of bumpy road conditions or internal leakage in the outrigger cylinder 610, the pressure-maintaining effect of the first hydraulic lock 412 prevents the outrigger from falling off. That is, in the event of a sudden pressure loss in the garbage truck hydraulic system 1000, the first hydraulic lock 412 prevents the outrigger cylinder 610 from moving due to leakage or its own weight, avoiding accidents and thus improving the safety and reliability of the entire garbage truck hydraulic system 1000.

[0046] The control principle of the circuits controlling the outrigger cylinder 610 and the lifting cylinder 620 is as follows: When the first directional valve 510 is energized and in the first state, the bidirectional solenoid directional valve 411 is energized and in the left position. The oil flows through the first directional valve 510 and the bidirectional solenoid directional valve 411, reaching the opening pressure of the first hydraulic lock 412 and entering the rodless chamber of the outrigger cylinder 610 and the lifting cylinder 620. Due to the difference between the weight of the garbage bin itself and the load weight of the outriggers, the outrigger cylinder 610 extends first, and the lifting cylinder 620 extends later. Then, the oil flows back to the main return oil circuit 320 through the rod chamber of the outrigger cylinder 610 and the lifting cylinder 620, and flows back to the oil tank 100 through the return oil filter, completing the action of lifting the garbage bin and extending the outriggers. When the first directional valve 510 is energized and in the second state, the oil flows out of the oil tank 100, passes through the first directional valve 510, flows into the rod chamber of the lifting cylinder 620, and then flows back from the rodless chamber of the lifting cylinder 620 to the main return oil circuit 320, and back to the oil tank 100, causing the garbage bin to descend. After the garbage bin descends to its final position, the bidirectional solenoid directional valve 411 is energized, i.e., the bidirectional solenoid directional valve 411 is in the left position. The oil flows through the first directional valve 510, reaches the opening pressure of the first hydraulic lock 412, flows into the rod chamber of the outrigger cylinder 610, then passes through the rodless chamber of the outrigger cylinder 610, and flows back through the bidirectional solenoid directional valve 411 to the main return oil circuit 320, and back to the oil tank 100, executing the outrigger retraction action. When the first directional valve 510 is in the third state, the bidirectional solenoid directional valve 411 is de-energized and in the right position, which is a bidirectional cut-off state. That is, oil cannot enter or leave the outrigger oil circuit 410 and the lifting oil circuit 420. As the pressing mechanism and the feeding mechanism frequently pressurize, the bidirectional solenoid directional valve 411 is de-energized, that is, the bidirectional solenoid directional valve 411 is in the right position. Even if oil leaks from the first directional valve 510, it cannot pass through the bidirectional solenoid directional valve 411. The oil cannot reach the opening condition of the first hydraulic lock 412, so the outrigger cylinder 610 does not extend and the outrigger will not fall off.

[0047] Please see Figure 2 In this embodiment, the second reversing valve 520, the third reversing valve 530, and the fourth reversing valve 540 are all three-position four-way reversing valves. The second reversing valve 520 has ports T2, P2, A2, and B2; the third reversing valve 530 has ports T3, P3, A3, and B3; and the fourth reversing valve 540 has ports P4, A4, and B4. Ports P2, P3, and P4 are connected to the main oil inlet circuit 310, and ports T2, T3, and T4 are connected to the main oil return circuit 320. Ports A2, A3, A4, and B2, B3, and B4 are used to connect the rodless chamber and the rod chamber of the scraper cylinder 630, the sliding plate cylinder 640, and the tipping cylinder 650, respectively. When the second directional valve 520 is in the first state, port P2 and port A2 are connected, and port B2 and port T2 are connected. When the second directional valve 520 is in the second state, port P2 is connected to port B2, and port A2 is connected to port T2. When the third directional valve 530 is in the first state, port P3 and port A3 are connected, and port B3 and port T3 are connected. When the third directional valve 530 is in the second state, port P3 is connected to port B3, and port A3 is connected to port T3.

[0048] When the fourth directional valve 540 is in the first state, port P4 and port A4 are connected, and port B4 and port T4 are connected. When the fourth directional valve 540 is in the second state, port P4 is connected to port B4, and port A4 is connected to port T4.

[0049] When any one of the second reversing valve 520, the third reversing valve 530, or the fourth reversing valve 540 is in the first or second state, the first reversing valve 510 is in the third state.

[0050] When the compaction mechanism is operating the sliding plate to compress the waste, the scraper may open prematurely or the compaction time may be insufficient due to the pressure exerted by the sliding plate or the feeding mechanism. This reduces the compression force on the waste, affects the waste compression density, and thus reduces the overall load capacity of the vehicle. In addition, during the feeding process, the vibration of the feeding mechanism can cause waste to spill, generate impacts, or produce noise.

[0051] To resolve the above issues, please refer to [link / reference]. Figure 2 The garbage truck hydraulic system 1000 in this embodiment further includes a second hydraulic lock 431, which is disposed between the second directional valve 520 and the scraper cylinder 630; and / or, the second directional valve 520 is a Y-type three-position four-way directional valve, in which the P2 port is disconnected and the T2 port is simultaneously connected to both the A2 and B2 ports when the second directional valve 520 is in the third state; and / or, the garbage truck hydraulic system 1000 further includes a third hydraulic lock 441, which is disposed between the third directional valve 530 and the sliding plate cylinder 640; and / Or, the third directional valve 530 is a Y-type three-position four-way directional valve. When the third directional valve 530 is in the third state, port P3 is disconnected, and port T3 is connected to ports A3 and B3; and / or, the garbage truck hydraulic system 1000 also includes a fourth hydraulic lock 451, which is located between the fourth directional valve 540 and the tipping cylinder 650; and / or, the fourth directional valve 540 is a Y-type three-position four-way directional valve. When the fourth directional valve 540 is in the third state, port P4 is disconnected, and port T4 is connected to ports A4 and B4.

[0052] In this embodiment, the second directional valve 520, the third directional valve 530, and the fourth directional valve 540 are all Y-type three-position four-way directional valves. Of course, the second directional valve 520, the third directional valve 530, and the fourth directional valve 540 can also be other types of directional valves depending on the actual working conditions, and are not limited here. The second directional valve 520, the third directional valve 530, and the fourth directional valve 540 can be the same type of directional valve, or they can be different types of directional valves, and are not limited here.

[0053] When the compaction mechanism performs a combined action, that is, when the scraper cylinder 630, the slide cylinder 640, or the bucket tilting cylinder 650 is activated, the second reversing valve 520, the third reversing valve 530, or the fourth reversing valve 540 is in the first state or the second state.

[0054] When the second directional valve 520 is in the third state (neutral position), the flow of oil is blocked to prevent leakage from the second directional valve 520 when other cylinders are working in conjunction, which could cause the corresponding cylinder to actuate prematurely, resulting in insufficient compaction time and reduced garbage compression density and loading capacity. Furthermore, the hydraulic lock enables bidirectional pressure maintenance, reducing leakage when the second directional valve 520 is in the third state (neutral position). This allows the scraper cylinder 630 to apply positive compression force to the garbage for a longer period during compaction, resulting in higher garbage compaction density and increased garbage loading capacity. Because the hydraulic lock forms an interlocking structure with two check valves, when the third directional valve 530 is in the third state (neutral position), the flow of oil is blocked. The hydraulic lock also enables bidirectional pressure maintenance, reducing leakage when the third directional valve 530 is in the neutral position. This prevents the sliding plate cylinder 640 from actuating under the reaction force of the garbage when other cylinders are working in conjunction, ensuring the effectiveness and efficiency of the compaction mechanism. Because the hydraulic lock forms an interlocking structure through two one-way valves, it blocks the flow of oil when the fourth directional valve 540 is in the third state, i.e., the neutral position. Furthermore, by setting the hydraulic lock, bidirectional pressure maintenance can be achieved, reducing the leakage of the fourth directional valve 540 in the neutral position. This ensures that the tipping cylinder 650 will not move when other cylinders are working together, thereby preventing vibration that could cause garbage to spill or impact and generate noise.

[0055] To reduce leakage when the second directional valve 520 is in the neutral position, the second directional valve 520 in this embodiment is a Y-type three-position four-way valve. For details, please refer to... Figure 3 , Figure 3This is a schematic diagram comparing the scraping pressure of the scraper in the O-type and Y-type positions of the electromagnetic directional valve provided in an embodiment of the present invention. △P1 is the leakage pressure of the electromagnetic directional valve in the O-type position, and △P2 is the leakage pressure of the electromagnetic directional valve in the Y-type position. The time to reach the rated pressure in the Y-type position is much longer than that in the O-type position, which makes the scraper spend more time scraping the waste, and the scraper opens more slowly, thereby increasing the waste compression time, increasing the waste density, and thus increasing the waste loading capacity.

[0056] In some embodiments, to reduce leakage when the third directional valve 530 is in the neutral position, the third directional valve 530 is a Y-type three-position four-way valve. Similarly, the slide plate oil circuit 440 uses both a Y-type three-position four-way valve and a hydraulic lock control to ensure that the slide plate will not slide backward during the sliding process of the slide plate driving the scraper, thereby achieving precise positioning of the slide plate and ensuring compaction efficiency and compaction effect.

[0057] In some embodiments, to reduce leakage when the fourth directional valve 540 is in the neutral position, the fourth directional valve 540 is a Y-type three-position four-way valve. Similarly, the tipping drum hydraulic circuit 450 uses both a Y-type three-position four-way valve and a hydraulic lock for control, making it less likely for the tipping drum cylinder 650 to move when other cylinders are working in conjunction, thereby preventing the feeding mechanism from vibrating and causing garbage to spill, generate impact, or produce noise.

[0058] When the second directional valve 520 is energized and in the first state, the oil flows from the main oil inlet 310 to the port of the second directional valve 520, flows out through port A2, and flows to the second hydraulic lock 431. When the opening pressure of the second hydraulic lock 431 is reached, the oil flows to the rodless chamber of the scraper cylinder 630, and then through the rod chamber of the scraper cylinder 630, flows back to the main return oil circuit 320 through the port of the second directional valve 520 and port T2, and flows back to the oil tank 100 through the return oil port, thus performing the scraper scraping action. When the second directional valve 520 is energized and in its second state, oil flows from the main inlet 310 to the second directional valve 520, passing through port P2 and port B2, and then to the second hydraulic lock 431. Upon reaching the opening pressure of the second hydraulic lock 431, the oil flows to the rod chamber of the scraper cylinder 630, then through the rodless chamber of the scraper cylinder 630, passing through the port of the second directional valve 520 and port T2, returning to the main return line 320, and finally flowing back to the oil tank 100 via the return port to perform the scraper opening action. When the second directional valve 520 is de-energized and in its third state, i.e., when the second directional valve 520 is in the neutral position with pressure buildup, the presence of the second hydraulic lock 431 ensures almost no leakage when the second directional valve 520 is in the neutral position. This guarantees that the scraper cylinder 630 maintains pressure for a longer period during the compaction process, ensuring the compaction density and thus increasing the loading capacity.

[0059] When the second directional valve 520 is energized and in the first state, the oil flows from the main oil inlet 310 to the port of the second directional valve 520, flows out through port A2, and flows to the second hydraulic lock 431. When the opening pressure of the second hydraulic lock 431 is reached, the oil flows to the rodless chamber of the scraper cylinder 630, and then through the rod chamber of the scraper cylinder 630, flows back to the main return oil circuit 320 through the port of the second directional valve 520 and port T2, and flows back to the oil tank 100 through the return oil port, thus performing the scraper scraping action. When the second directional valve 520 is energized and in the second state, the oil flows from the main inlet 310 to the second directional valve 520, passes through port P2 and port B2 in sequence, and flows to the second hydraulic lock 431. When the opening pressure of the second hydraulic lock 431 is reached, the oil flows to the rod chamber of the scraper cylinder 630, and then through the rodless chamber of the scraper cylinder 630, passes through port T2 of the second directional valve 520 in sequence and flows back to the main return oil circuit 320. Finally, it flows back to the oil tank 100 through the return oil port to perform the scraper opening action. When the second directional valve 520 is de-energized and in the third state, that is, when the second directional valve 520 is in the neutral position and under pressure, the second hydraulic lock 431 ensures that there is almost no leakage when the second directional valve 520 is in the neutral position. This ensures that the scraper cylinder 630 will not act prematurely or the scraper will not open prematurely during the compaction process, thus ensuring a longer pressure holding time for the compression force on the waste, ensuring the compaction density of the waste, and thereby increasing the loading capacity.

[0060] When the third directional valve 530 is energized and in the first state, the oil flows from the main oil inlet 310 to the port of the third directional valve 530, flows out through port A3, and flows to the third hydraulic lock 441. When the opening pressure of the third hydraulic lock 441 is reached, the oil flows to the rodless chamber of the slide plate cylinder 640, and then through the rod chamber of the slide plate cylinder 640, flows back to the main return oil circuit 320 through the port of the third directional valve 530 and port T3, and flows back to the oil tank 100 through the return oil port, thus performing the slide plate upward movement. When the third directional valve 530 is energized and in the second state, the oil flows from the main inlet 310 to the third directional valve 530, passes through port P3 and port B3, and flows to the third hydraulic lock 441. Upon reaching the opening pressure of the third hydraulic lock 441, the oil flows to the rod chamber of the slide plate cylinder 640, then through the rodless chamber of the slide plate cylinder 640, passes through the port of the third directional valve 530 and port T3, and flows back to the main return line 320. Finally, it flows back to the oil tank 100 through the return port to execute the slide plate's downward movement. When the third directional valve 530 is de-energized and in the third state, i.e., when the third directional valve 530 is in the neutral position with pressure buildup, the presence of the third hydraulic lock 441 ensures that there is almost no leakage when the third directional valve 530 is in the neutral position. This prevents the slide plate cylinder 640 from prematurely actuating during the compaction process, ensuring a longer pressure holding time for the compression force on the waste, maintaining the waste compaction density, and thus increasing the loading capacity.

[0061] When the fourth directional valve 540 is energized and in the first state, the oil flows from the main oil inlet 310 to the port of the fourth directional valve 540, flows out through port A4, and flows to the fourth hydraulic lock 451. When the opening pressure of the fourth hydraulic lock 451 is reached, the oil flows to the rodless chamber of the tipping cylinder 650, and then through the rod chamber of the tipping cylinder 650, flows back to the main return oil circuit 320 through the port of the fourth directional valve 540 and port T4, and flows back to the oil tank 100 through the return oil port, thus performing the tipping action of tilting the drum upward. When the fourth directional valve 540 is energized and in its second state, oil flows from the main inlet 310 to the fourth directional valve 540, passing through port P4 and port B4, and then to the fourth hydraulic lock 451. Upon reaching the opening pressure of the fourth hydraulic lock 451, the oil flows to the rod chamber of the tipping cylinder 650, then through the rodless chamber of the tipping cylinder 650, passing through the port of the fourth directional valve 540 and port T4, returning to the main return line 320. Finally, it flows back to the oil tank 100 via the return port to perform the tipping action. When the fourth directional valve 540 is de-energized and in its fourth state (i.e., in the neutral position with pressure buildup), the fourth hydraulic lock 451 ensures almost no leakage in this neutral position, preventing premature action of the tipping cylinder 650 and thus preventing the feeding mechanism from vibrating, causing garbage spillage, impact, or noise.

[0062] In addition, to control the operating efficiency of the scraper cylinder 630 or the slide plate cylinder 640, please refer to [link / reference needed]. Figure 2 The garbage truck hydraulic system 1000 in this embodiment also includes a second overflow valve 810, one end of which is connected to the oil return port of the oil tank 100, and the other end of which is connected to the rodless chamber of the scraper cylinder 630; and / or, the garbage truck hydraulic system 1000 also includes a third overflow valve 820, one end of which is connected to the oil return port of the oil tank 100, and the other end of which is connected to the rodless chamber of the sliding plate cylinder 640. By setting the second overflow valve 810, the reaction force of the garbage compression density can be ensured, and the compression force of the scraper can be ensured to be sufficient; by setting the third overflow valve 820, the pressure set value at the sliding plate can be ensured, and the reaction force of the scraper can be ensured to be sufficient, preventing premature opening. The second overflow valve 810 and the third overflow valve 820 can be set simultaneously, or only one of them can be set, depending on the actual use requirements, and is not limited here. In addition, an overflow valve can be installed on the tipping oil circuit 450. One end of the overflow valve is connected to the oil return port of the oil tank 100, and the other end of the overflow valve is connected to the rodless chamber of the tipping cylinder 650.

[0063] For ease of automated control, the first directional valve 510, the second directional valve 520, the third directional valve 530, and the fourth directional valve 540 in this embodiment are all electromagnetic directional valves. Of course, the first directional valve 510, the second directional valve 520, the third directional valve 530, and the fourth directional valve 540 can also be manual directional valves, motorized directional valves, electro-hydraulic directional valves, etc., and are not limited here.

[0064] Please continue reading. Figure 2In this embodiment, the garbage truck hydraulic system 1000 further includes a first relief valve 700, which is disposed between the main oil inlet circuit 310 and the main oil return circuit 320; and / or, the garbage truck hydraulic system 1000 further includes a fifth directional valve 900, which is disposed between the main oil inlet circuit 310 and the main oil return circuit 320. In this embodiment, the garbage truck hydraulic system 1000 may be equipped with either the first relief valve 700 or the fifth directional valve 900 separately, or both simultaneously; this is not limited here. By providing the first relief valve 700, the safety and pressure stability of the entire garbage truck hydraulic system 1000 can be ensured. The first relief valve 700, by limiting the pressure rise, prevents damage to components and circuits in the garbage truck hydraulic system 1000 due to excessive pressure. Furthermore, the first overflow valve 700 can maintain the pressure of the garbage truck hydraulic system 1000 within a certain range, preventing system instability due to excessive pressure. By setting a fifth directional valve 900, when the fifth directional valve 900 is energized, the oil in the oil tank 100 flows directly from the main inlet oil line 310 through the fifth directional valve 900 to the main return oil line 320, and then back to the oil tank 100, achieving unloading. This unloading oil circuit allows the oil pump 200 to operate with near-zero power loss without frequent starting and stopping, thereby reducing power loss and system heat generation.

[0065] To improve the control accuracy and response speed of the bidirectional electromagnetic directional valve 411, the garbage truck hydraulic system 1000 in this embodiment also includes a lifting oil circuit 420. The lifting oil circuit 420 is connected in parallel with the outrigger oil circuit 410. The lifting cylinder 620 is located in the lifting oil circuit 420. The first directional valve 510 enables one of the rod-side chamber and the rodless chamber of the lifting cylinder 620 to be connected to the main inlet oil circuit 310, and the other to be connected to the main return oil circuit 320. The vehicle body includes a garbage bin, a subframe, and outriggers. The lifting cylinder 620 is connected between the subframe and the garbage bin. The lifting cylinder 620 is used to control the lifting and lowering of the garbage bin, thereby realizing the loading and unloading of garbage. The subframe is equipped with a proximity switch. When the first directional valve 510 is connected to the main oil inlet circuit 310, the bidirectional solenoid directional valve 411 is energized, the outrigger oil circuit 410 is opened first, the outrigger cylinder 610 extends and drives the outrigger to extend. After the outrigger cylinder 610 extends to the position, the lifting oil circuit 420 is opened, the lifting cylinder 620 extends and drives the garbage bin to lift. When the first directional valve 510 is connected to the main return oil circuit 320, the lifting oil circuit 420 is opened first, the lifting cylinder 620 retracts and drives the garbage bin to descend. When the garbage bin descends to contact the subframe, the proximity switch is energized, controlling the bidirectional solenoid directional valve 411 to be energized, the outrigger oil circuit 410 is opened, the outrigger cylinder 610 retracts and drives the outrigger to retract.

[0066] Furthermore, in this embodiment, the garbage truck hydraulic system 1000 is equipped with a filter at the inlet of the oil tank 100. This filter removes impurities from the hydraulic fluid, such as metal shavings, dust, and dirt. Clean hydraulic fluid reduces wear on pumps, valves, and other components, thereby extending the equipment's lifespan and reducing the frequency of maintenance and component replacement. Moreover, impurities in the hydraulic fluid affect its flowability, which in turn affects the efficiency of the garbage truck hydraulic system 1000. Using a filter keeps the hydraulic fluid clean, ensuring the garbage truck hydraulic system 1000 operates at its optimal state and improving overall efficiency. Additionally, the accumulation of contaminants can lead to system malfunctions, such as oil circuit blockages and component jamming. Installing a filter effectively reduces the occurrence of these malfunctions and improves system reliability. Of course, the filter can also be installed at the outlet of the oil tank 100, or simultaneously at both the inlet and outlet of the oil tank 100; this is not limited to this embodiment.

[0067] An embodiment of the present invention also provides a hydraulic control method for a garbage truck, applied to the garbage truck hydraulic system 1000 in any of the above embodiments or the garbage truck in any of the above embodiments, the control method comprising: Hydraulic oil is pumped from oil tank 100 to main oil inlet 310 by oil pump 200; Control at least one of the first reversing valve 510, the second reversing valve 520, the third reversing valve 530 and the fourth reversing valve 540 to activate the main oil inlet circuit 310 to connect with the rod or rodless chamber of the corresponding outrigger cylinder 610, scraper cylinder 630, slide plate cylinder 640 or tipping cylinder 650, and at the same time connect the main return oil circuit 320 to the corresponding rodless or rod chamber. When the scraper cylinder 630, the sliding plate cylinder 640, or the tipping cylinder 650 performs a combined extension and retraction action, that is, when at least one of the scraper oil circuit 430, the sliding plate oil circuit 440, and the tipping oil circuit 450 is connected to the main oil inlet circuit 310 and the main oil return circuit 320, the first reversing valve 510 is controlled to switch to the third state, and the bidirectional solenoid reversing valve 411 is controlled to be in the right position, so that the rodless chamber of the outrigger cylinder 610 is locked, thereby preventing the outrigger cylinder 610 from extending.

[0068] That is, the scraper cylinder 630, the sliding plate cylinder 640, or the tipping cylinder 650 can operate simultaneously, or only one or two cylinders can operate. By switching the state of the directional valve corresponding to each cylinder, at least one of the three oil circuits (scraper circuit 430, sliding plate circuit 440, and tipping cylinder 450) can be connected to the main inlet circuit 310 and the main return circuit 320 to control at least one of the following cylinders to operate: scraper cylinder 630, sliding plate cylinder 640, or tipping cylinder 650. During the combined operation, the first directional valve 510 of the outrigger cylinder 610 is in the neutral position and is in a de-energized bidirectional cut-off state through the bidirectional solenoid directional valve 411, keeping the outrigger cylinder 610 locked to prevent the outrigger from falling off.

[0069] In addition, the control method also includes: when the outrigger cylinder 610 needs to be activated, controlling the bidirectional solenoid valve 411 to be in the left position, and controlling the first directional valve 510 to switch to the first state or the second state to realize the extension or retraction of the outrigger cylinder 610.

[0070] To facilitate control over the sequence of actions of the lifting cylinder 620 and the outrigger cylinder 610, thereby improving safety during garbage truck operation, the garbage truck hydraulic system 1000 in this embodiment further includes a lifting oil circuit 420. The lifting oil circuit 420 and the outrigger oil circuit 410 are connected in parallel. The lifting cylinder 620 is located in the lifting oil circuit 420. The first reversing valve 510 enables one of the rod-side chamber and the rodless chamber of the lifting cylinder 620 to be connected to the main inlet oil circuit 310, and the other to be connected to the main return oil circuit 320. The vehicle body includes a garbage bin, a subframe, and outriggers. The lifting cylinder 620 is connected between the subframe and the garbage bin. The subframe is equipped with a proximity switch. The proximity switch is used to detect the relative position of the garbage bin and the subframe. Control methods also include: When the first directional valve 510 is switched to be connected to the main oil inlet circuit 310, the bidirectional solenoid directional valve 411 is energized, so that the bidirectional solenoid directional valve 411 is in a state of being energized and connected at both ports, so that the outrigger oil circuit 410 is opened first, driving the outrigger cylinder 610 to extend, thereby driving the outrigger to extend; after the outrigger is extended to the position, the lifting oil circuit 420 is opened, driving the lifting cylinder 620 to extend and driving the garbage bin to lift. When the first reversing valve 510 is connected to the main return oil circuit 320, the lifting oil circuit 420 is connected first, the lifting cylinder 620 retracts and drives the garbage bin to descend; when the garbage bin descends to contact the subframe, the proximity switch is detected and triggered to energize the bidirectional electromagnetic reversing valve 411, which connects the outrigger oil circuit 410, drives the outrigger cylinder 610 to retract and drives the outrigger to retract.

[0071] That is, the lifting cylinder 620 and the outrigger cylinder 610 are controlled by the same first directional valve 510, and their actions are timed through the sequential opening and closing of the hydraulic circuit. Because there is a significant weight difference between the garbage bin and the outriggers, the extension action of the outrigger cylinder 610 and the lifting action of the lifting cylinder 620 are controlled sequentially; the lifting cylinder 620 only activates after the outriggers are fully extended. When the garbage bin is lowered, the lifting cylinder 620 retracts first. Once the proximity switch detects that the garbage bin has reset (i.e., when the proximity switch detects that the garbage bin has descended to contact the subframe), it sends a signal to energize the bidirectional solenoid directional valve 411. At this point, the outrigger hydraulic circuit 410 is opened, and the outrigger cylinder 610 retracts, driving the outriggers to retract as well. The bidirectional solenoid directional valve 411 remains energized during the outrigger extension or retraction phases, and is de-energized during other phases to lock the outrigger cylinder 610.

[0072] In summary, the hydraulic system 1000 of this garbage truck includes an oil tank 100, an oil pump 200, a main oil inlet circuit 310, a main oil return circuit 320, a first directional valve 510, a second directional valve 520, a third directional valve 530, a fourth directional valve 540, an outrigger oil circuit 410, a scraper oil circuit 430, a sliding plate oil circuit 440, a tipping drum oil circuit 450, and a two-way electromagnetic directional valve 411; the outlet of the oil tank 100 is connected to the suction port of the oil pump 200, and the outlet of the oil pump 200 is connected to the main oil inlet circuit 310. The return port of the oil tank 100 is interconnected with the main return oil circuit 320; the first reversing valve 510, the second reversing valve 520, the third reversing valve 530, and the fourth reversing valve 540 are all connected in parallel between the main inlet oil circuit 310 and the main return oil circuit 320; the outrigger cylinder 610 is installed in the outrigger oil circuit 410, and the first reversing valve 510 enables one of the rod chamber and the rodless chamber of the outrigger cylinder 610 to be connected to the main inlet oil circuit 310, and the other to be connected to the main return oil circuit 320; the scraper cylinder 630 is installed in the scraper oil circuit 430. 0. The second directional valve 520 enables one of the rod-side and rodless chambers of the scraper cylinder 630 to be connected to the main oil inlet circuit 310, and the other to be connected to the main oil return circuit 320; the slide plate cylinder 640 is located in the slide plate circuit 440, and the third directional valve 530 enables one of the rod-side and rodless chambers of the slide plate cylinder 640 to be connected to the main oil inlet circuit 310, and the other to be connected to the main oil return circuit 320; the tilting cylinder 650 is located in the tilting cylinder circuit 450, and the fourth directional valve 540 enables the tilting cylinder 650 to be connected to the main oil return circuit 320. One of the rod-side chamber and the rodless chamber of the 0 is connected to the main oil inlet circuit 310, and the other is connected to the return oil line; the bidirectional electromagnetic reversing valve 411 is located between the first reversing valve 510 and the rodless chamber of the outrigger cylinder 610; under the drive of the oil pump 200, the scraper cylinder 630, the sliding plate cylinder 640, and the tipping cylinder 650 perform compound actions. When any one of the scraper cylinder 630, the sliding plate cylinder 640, and the tipping cylinder 650 performs a compound extension and retraction action, the outrigger cylinder 610 remains locked. By setting a bidirectional electromagnetic reversing valve 411, when other oil circuits are in combined operation, and when the first reversing valve 510 is in the neutral position and under pressure, and the first reversing valve 510 has internal leakage, leakage in the outrigger oil circuit 410 can be prevented. This prevents the outrigger cylinder 610 from extending when the outrigger oil circuit 410 is not connected to the main inlet oil circuit 310 and the main return oil circuit 320, thus preventing the outrigger from falling off. This ensures the driving safety of the garbage truck and improves its reliability.

[0073] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A refuse truck hydraulic system, characterized by, include: The oil tank (100), oil pump (200), main oil inlet (310), and main oil return (320) are connected. The oil outlet of the oil pump (200) is connected to the main oil inlet (310), and the oil return port of the oil tank (100) is connected to the main oil return (320). The first reversing valve (510), the second reversing valve (520), the third reversing valve (530), and the fourth reversing valve (540) are all connected in parallel between the main oil inlet circuit (310) and the main oil return circuit (320); The system includes a support leg hydraulic circuit (410), a scraper hydraulic circuit (430), a sliding plate hydraulic circuit (440), and a tipping drum hydraulic circuit (450). A support leg cylinder (610) is installed in the support leg hydraulic circuit (410); a scraper cylinder (630) is installed in the scraper hydraulic circuit (430); a sliding plate cylinder (640) is installed in the sliding plate hydraulic circuit (440); and a tipping drum cylinder (650) is installed in the tipping drum hydraulic circuit (450). The first reversing valve (510), the second reversing valve (520), the third reversing valve (530), and the fourth reversing valve (540) can respectively connect one of the rod-side and rodless-side chambers of the outrigger cylinder (610), the scraper cylinder (630), the sliding plate cylinder (640), and the tipping cylinder (650) to the main oil inlet circuit (310), and the other to the main return oil circuit (320); A two-way electromagnetic reversing valve (411) is disposed between the first reversing valve (510) and the rodless chamber of the outrigger cylinder (610); under the drive of the oil pump (200), the scraper cylinder (630), the sliding plate cylinder (640), and the tipping cylinder (650) perform a combined action. When any one of the scraper cylinder (630), the sliding plate cylinder (640), and the tipping cylinder (650) performs a combined extension and retraction action, the outrigger cylinder (610) remains locked.

2. The hydraulic system for garbage trucks according to claim 1, characterized in that, The bidirectional electromagnetic reversing valve (411) has a left position and a right position. When the bidirectional electromagnetic reversing valve (411) is in the left position, both ports of the bidirectional electromagnetic reversing valve (411) are energized and connected. When the bidirectional electromagnetic reversing valve (411) is in the right position, the bidirectional electromagnetic reversing valve (411) is de-energized and cut off in both directions.

3. The hydraulic system for garbage trucks according to claim 2, characterized in that, The first reversing valve (510) is an O-type three-position four-way reversing valve with ports T1, P1, A1, and B1. Port P1 is connected to the main oil inlet circuit (310), port T1 is connected to the main oil return circuit (320), and ports A1 and B1 are respectively used to connect the rodless chamber and the rod chamber of the outrigger cylinder (610). When the first reversing valve (510) is in the first state, the P1 port and the A1 port are connected, and the B1 port and the T1 port are connected; When the first reversing valve (510) is in the second state, the P1 port is connected to the B1 port, and the A1 port is connected to the T1 port; When the first reversing valve (510) is in the third state, the P1 port is not connected to the A1 port and the B1 port, and the T1 port is not connected to the A1 port and the B1 port. When the bidirectional solenoid directional valve (411) is in the right position, the first directional valve (510) is in the third state.

4. The hydraulic system for garbage trucks according to claim 3, characterized in that, The second reversing valve (520), the third reversing valve (530), and the fourth reversing valve (540) are all three-position four-way reversing valves. The second reversing valve (520) has ports T2, P2, A2, and B2. The third reversing valve (530) has ports T3, P3, A3, and B3. The fourth reversing valve (540) has ports T4, P4, A4, and B4. Ports P2, P3, and P4 are respectively connected to the main oil inlet circuit (310). Ports T2, T3, and T4 are respectively connected to the main oil return circuit (320). Ports A2, A3, and A4 and ports B2, B3, and B4 are respectively used to connect the rodless chamber and rod chamber of the scraper cylinder (630), the sliding plate cylinder (640), and the tipping cylinder (650). When the second reversing valve (520) is in the first state, the P2 port and the A2 port are connected, and the B2 port and the T2 port are connected; When the second directional valve (520) is in the second state, port P2 is connected to port B2, and port A2 is connected to port T2; When the third reversing valve (530) is in the first state, the P3 port and the A3 port are connected, and the B3 port and the T3 port are connected; When the third reversing valve (530) is in the second state, the P3 port is connected to the B3 port, and the A3 port is connected to the T3 port; When the fourth reversing valve (540) is in the first state, the P4 port and the A4 port are connected, and the B4 port and the T4 port are connected; When the fourth reversing valve (540) is in the second state, the P4 port is connected to the B4 port, and the A4 port is connected to the T4 port; When any one of the second reversing valve (520), the third reversing valve (530), or the fourth reversing valve (540) is in the first state or the second state, the first reversing valve (510) is in the third state.

5. The hydraulic system for garbage trucks according to claim 1, characterized in that, The garbage truck hydraulic system (1000) also includes a first hydraulic lock (412), which is located between the outrigger cylinder (610) and the first directional valve (510).

6. The hydraulic system for garbage trucks according to claim 1, characterized in that, The hydraulic system (1000) of the garbage truck also includes a lifting oil circuit (420), which is connected in parallel with the outrigger oil circuit (410). A lifting cylinder (620) is installed in the lifting oil circuit (420). The first reversing valve (510) enables one of the rod chamber and the rodless chamber of the lifting cylinder (620) to be connected to the main inlet oil circuit (310), and the other to be connected to the main return oil circuit (320). A balance valve (421) is installed between the lifting cylinder (620) and the first reversing valve (510).

7. The hydraulic system for garbage trucks according to claim 4, characterized in that, The garbage truck hydraulic system (1000) also includes a second hydraulic lock (431), which is located between the second directional valve (520) and the scraper cylinder (630); And / or, the second directional valve (520) is a Y-type three-position four-way directional valve. When the second directional valve (520) is in the third state, the P2 port is open, and both the A2 port and the B2 port are connected to the T2 port; and / or, The garbage truck hydraulic system (1000) also includes a third hydraulic lock (441), which is located between the third directional valve (530) and the sliding plate cylinder (640); And / or, the third directional valve (530) is a Y-type three-position four-way directional valve. When the third directional valve (530) is in the third state, port P3 is open, and ports A3 and B3 are both connected to port T3; and / or, The garbage truck hydraulic system (1000) also includes a fourth hydraulic lock (451), which is located between the fourth directional valve (540) and the tipping cylinder (650); And / or, the fourth directional valve (540) is a Y-type three-position four-way directional valve. When the fourth directional valve (540) is in the third state, the P4 port is disconnected, and the A4 port and the B4 port are both connected to the T4 port.

8. The hydraulic system for garbage trucks according to claim 1, characterized in that, The garbage truck hydraulic system (1000) further includes a first relief valve (700), which is disposed between the main oil inlet circuit (310) and the main oil return circuit (320); and / or, The garbage truck hydraulic system (1000) also includes a fifth directional valve (900), which is located between the main oil inlet circuit (310) and the main oil return circuit (320).

9. A garbage truck, characterized in that, The vehicle includes a vehicle body and a garbage truck hydraulic system (1000) as described in any one of claims 1-8, wherein the garbage truck hydraulic system (1000) is disposed on the vehicle body.

10. A hydraulic control method for a garbage truck, applied to the hydraulic system of the garbage truck according to any one of claims 1-8 or the garbage truck according to claim 9, characterized in that, The control method includes: Hydraulic oil is pumped from the oil tank (100) to the main oil inlet (310) by the oil pump (200). Control at least one of the first reversing valve (510), the second reversing valve (520), the third reversing valve (530), and the fourth reversing valve (540) to activate the main oil inlet circuit (310) to connect with the rod or rodless chamber of the corresponding outrigger cylinder (610), scraper cylinder (630), slide plate cylinder (640), or tipping cylinder (650), while the main return oil circuit (320) connects with the corresponding rodless or rod chamber. When the scraper cylinder (630), the sliding plate cylinder (640), or the tipping cylinder (650) performs a combined extension and retraction action, that is, when at least one of the scraper oil circuit (430), the sliding plate oil circuit (440), and the tipping oil circuit (450) is connected to the main inlet oil circuit (310) and the main return oil circuit (320), the first reversing valve (510) is controlled to switch to the third state, and the bidirectional electromagnetic reversing valve (411) is controlled to be in the right position, so that the rodless chamber of the outrigger cylinder (610) is locked, thereby preventing the outrigger cylinder (610) from extending.

11. The hydraulic control method for a garbage truck according to claim 10, characterized in that, The control method further includes: When the outrigger cylinder (610) needs to be activated, the bidirectional electromagnetic reversing valve (411) is controlled to be in the left position, and the first reversing valve (510) is controlled to switch to the first state or the second state to realize the extension or retraction of the outrigger cylinder (610).

12. The hydraulic control method for a garbage truck according to claim 10 or 11, characterized in that, The hydraulic system (1000) of the garbage truck also includes a lifting oil circuit (420), which is connected in parallel with the outrigger oil circuit (410). A lifting cylinder (620) is installed in the lifting oil circuit (420). The first reversing valve (510) enables one of the rod chamber and the rodless chamber of the lifting cylinder (620) to be connected to the main inlet oil circuit (310), and the other to be connected to the main return oil circuit (320). The vehicle body includes a garbage bin, a subframe, and outriggers. The lifting cylinder (620) is connected between the subframe and the garbage bin. The subframe is equipped with a proximity switch. The proximity switch is used to detect the relative position of the trash can and the subframe; The control method further includes: When the first reversing valve (510) is switched to be connected to the main oil inlet (310), the bidirectional electromagnetic reversing valve (411) is energized, so that the bidirectional electromagnetic reversing valve (411) is in a state of being energized and connected at both ports, so that the outrigger oil circuit (410) is opened first, driving the outrigger cylinder (610) to extend, thereby driving the outrigger to extend; after the outrigger is extended to the position, the lifting oil circuit (420) is opened, driving the lifting cylinder (620) to extend and driving the garbage bin to lift; When the first reversing valve (510) is connected to the main return oil circuit (320), the lifting oil circuit (420) is connected first, the lifting cylinder (620) retracts and drives the garbage bin to descend; when the garbage bin descends to contact the subframe, the proximity switch is detected and the bidirectional electromagnetic reversing valve (411) is energized, so that the outrigger oil circuit (410) is connected, driving the outrigger cylinder (610) to retract and driving the outrigger to retract.

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