An excavator drive system

Abstract

The utility model relates to hydraulic technology field especially relates to a kind of excavator drive system, comprising: slewing drive unit, including slewing motor, mechanical drive executes slewing action;Boom drive unit, including first pump, boom control valve and boom cylinder;Stick drive unit, including second pump, stick control valve and stick cylinder;Walking-bucket drive unit, including third pump, fourth pump, walking control valve, bucket control valve, walking execution element, bucket cylinder and distribution valve, simultaneously execute walking and bucket action, the distribution valve controls the third pump oil supply to walking control valve, the fourth pump oil supply to bucket control valve;The first pump, second pump, third pump and fourth pump are driven by same pump motor.Solve the technical problem that the excavator in prior art adopts centralized control system to appear load coupling, cannot realize the accurate control under different working conditions.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic technology, and in particular to an excavator drive system. Background Technology

[0002] In the prior art, excavators generally use hydraulic transmission systems, employing a diesel engine to drive a hydraulic pump as a power source, providing high-pressure oil to an integrated multi-way valve for centralized control of various excavator actions. For example, application number CN201822074359.X discloses a novel integrated multi-way valve for excavators, wherein the multi-way valve body is provided with an oil inlet and an oil return port. The multi-way valve body includes a right valve body and a left valve body. The right valve body contains, in sequence, a right travel linkage, a slewing linkage, a boom linkage (secondary), a spare linkage, a stick linkage (primary), a first bypass shut-off valve, and a second bypass shut-off valve. Each of the right travel linkage, slewing linkage, boom linkage (secondary), spare linkage, stick linkage, first bypass shut-off valve, and second bypass shut-off valve is equipped with a valve core. The stick linkage (secondary) is also equipped with a stick locking valve. The boom linkage (secondary) and the slewing priority linkage are arranged in parallel. The slewing priority linkage is equipped with a slewing priority valve core. After the slewing priority valve core reverses, the central oil circuit of the right valve body is throttled, and the slewing linkage is given priority in oil supply, thus achieving the function of slewing priority. The left valve body sequentially includes a linear travel linkage, a left travel linkage, a boom linkage (unit 1), a bucket linkage, and a stick linkage (unit 2). Each of these linkages—linear travel, left travel, boom linkage (unit 1), bucket linkage, and stick linkage (unit 2)—is equipped with a valve core, specifically a linear travel valve core, a left travel valve core, a boom linkage (unit 1), a bucket linkage (unit 2), and a stick linkage (unit 2). A stick regeneration shut-off valve is also installed on the stick linkage (unit 1), controlling the regeneration flow rate based on the regeneration requirements of the rodless chamber of the stick linkage cylinder. A boom locking valve is also installed on the boom linkage (unit 1). A stick logic valve is located between the central oil passage of the left valve body and the stick linkage (unit 2). When the stick linkage and boom linkage are in combined operation, the boom lifting mechanism prioritizes oil supply to the stick retraction and extension movements, achieving coordinated performance of the combined actions.

[0003] Centralized control systems can experience load coupling, which primarily causes two problems: first, excess energy loss reduces the overall energy efficiency of the machine's transmission system, hindering the electrification of excavators; second, the mutual influence between different loads leads to poor performance in complex motion control. To address this issue, current control valves integrate numerous complex damping and logic valves, significantly increasing the complexity and cost of the hydraulic system. Furthermore, hydraulic damping and logic valves can only be matched to a single operating condition, failing to achieve precise control under different conditions, resulting in inconsistent machine performance under varying circumstances. Utility Model Content

[0004] To address the technical problem of load coupling in existing excavator centralized control systems, which prevents precise control under different working conditions, this invention provides an excavator drive system that solves the aforementioned technical problem.

[0005] To solve the above-mentioned technical problems, this utility model provides an excavator drive system, comprising: The rotary drive unit includes a rotary motor, which mechanically drives the rotary motion. The boom drive unit includes a first pump, a boom control valve, and a boom cylinder; The boom drive unit includes a second pump, a boom control valve, and a boom cylinder; The travel-bucket drive unit includes a third pump, a fourth pump, a travel control valve, a bucket control valve, a travel actuator, a bucket cylinder, and a distribution valve. When traveling and bucket actions are performed simultaneously, the distribution valve controls the third pump to supply oil to the travel control valve, and the fourth pump to supply oil to the bucket control valve. The first, second, third, and fourth pumps are driven by the same pump motor.

[0006] According to one embodiment of the present invention, the pump motor drives a one-to-two reducer, the first output end of the one-to-two reducer drives a first pump and a second pump, and the second output end of the one-to-two reducer drives a third pump and a fourth pump.

[0007] According to one embodiment of the present invention, a power supply and a controller are also included, wherein the power supply provides electrical energy to the rotary motor and the pump motor, and the controller drives the rotary motor and the pump motor.

[0008] According to one embodiment of the present invention, the walking actuator includes a left walking actuator and a right walking actuator, and the walking control valve includes a left walking control valve and a right walking control valve. The left walking control valve controls the oil inlet and outlet of the left walking actuator, and the right walking control valve controls the oil inlet and outlet of the right walking actuator.

[0009] According to one embodiment of the present invention, the third pump supplies oil to a distribution valve and a travel control valve, the fourth pump supplies oil to the distribution valve, one working port of the distribution valve is connected to another travel control valve, and one working port of the distribution valve is connected to a bucket control valve. When the distribution valve is in the first position, the third pump supplies oil to one travel control valve, and the fourth pump supplies oil to the other travel control valve via the distribution valve. When the distribution valve is in the second position, the third pump supplies oil to both travel control valves simultaneously, and the fourth pump supplies oil to the bucket control valve via the distribution valve.

[0010] According to one embodiment of the present invention, the boom control valve includes a boom main control valve and a one-way connecting oil circuit. When the boom main control valve controls the rod chamber of the boom cylinder to receive oil and the rodless chamber to return oil, the return oil from the rodless chamber can flow unidirectionally into the rod chamber of the boom cylinder through the one-way connecting oil circuit.

[0011] According to one embodiment of the present invention, the boom drive unit further includes a first anti-settlement valve group. The first anti-settlement valve group is located in the oil line between the boom main control valve and the rodless chamber of the boom cylinder. The first anti-settlement valve group includes a first cone valve and a first control valve. The first cone valve has a first oil port and a second oil port. The first oil port is connected to the boom main control valve, and the second oil port is connected to the rodless chamber of the boom cylinder. The first control valve controls the spring chamber of the first cone valve to connect with the second oil port or to unload the spring chamber of the first cone valve.

[0012] According to one embodiment of the present invention, the boom control valve includes a boom main control valve and a second anti-settlement valve assembly. The second anti-settlement valve assembly is located in the oil line between the boom main control valve and the rod chamber of the boom cylinder. The second anti-settlement valve assembly includes a second cone valve and a second control valve. The second cone valve has a third oil port and a fourth oil port. The third oil port is connected to the boom main control valve, and the fourth oil port is connected to the rod chamber of the boom cylinder. The second control valve controls the spring chamber of the second cone valve to connect with the fourth oil port or to unload the spring chamber of the second cone valve.

[0013] According to one embodiment of the present invention, it further includes a regeneration oil circuit, wherein the return oil from the rod chamber of the boom cylinder can enter the rodless chamber of the boom cylinder through the regeneration oil circuit, and the regeneration oil circuit can adjust the flow rate of the return oil from the rod chamber of the boom cylinder into the rodless chamber.

[0014] According to one embodiment of the present invention, the regeneration oil circuit includes a first oil circuit and a second oil circuit arranged in parallel. The first oil circuit is connected to a third oil port and the rodless chamber of the boom cylinder. A first valve is provided on the first oil circuit. The second oil circuit is connected to the third oil port and the return oil port. A second valve is provided on the second oil circuit. The first valve and the second valve control the opening degree of their respective oil circuits.

[0015] Based on the above technical solution, the technical effects that this utility model can achieve are as follows: This invention relates to an excavator drive system that isolates the three most frequently used and energy-consuming actuators—swing, boom, and stick—into separate drive units, effectively reducing the overall control system's power loss. For the travel-bucket drive unit, a distribution valve is used to allocate the flow to the third and fourth pumps, ensuring that when both travel and bucket actions are performed simultaneously, the third pump supplies oil to the travel mechanism and the fourth pump supplies oil to the bucket, preventing coupling. In other words, this excavator drive system allows for individual control of each actuator, eliminating load coupling issues in any complex actions and providing excellent control performance. Furthermore, the swing mechanism utilizes a mechanical drive motor, resulting in high energy conversion efficiency. The travel-bucket drive unit uses only two pumps, further reducing the number of pumps through decoupling. The first, second, third, and fourth pumps are driven by the same pump motor, saving on the number of pump motors, reducing the number of components, decreasing size, and lowering costs. In terms of control, the excavator drive system of this utility model controls the operation of the pump motor and the swing motor; the output flow request of each action is calculated and decomposed by the controller internally into the speed and displacement, and then the closed-loop control of the speed and displacement is controlled. The excavator drive system of this utility model, through the setting of the travel-bucket drive unit, can achieve the following: when traveling and bucket actions are performed simultaneously, the third pump supplies oil to the left and right travel simultaneously, and the fourth pump supplies oil to the bucket, without coupling between the two; when only traveling action is performed, the third and fourth pumps each supply oil to a travel control valve to perform the traveling action; when only bucket action is performed, the two travel control valves do not work, and the distribution valve can control the third or fourth pump to supply oil to the bucket control valve to perform the bucket action. The excavator drive system of this utility model has a one-way oil passage formed in the boom control valve, which facilitates the return oil from the rodless chamber of the boom cylinder to enter the rod chamber through the one-way oil passage, realizing the regeneration and reuse of the return oil. The boom drive unit also includes a first anti-settlement valve assembly. The first control valve can control the opening and closing of the first cone valve by controlling the oil pressure in the spring chamber of the first cone valve. When the rodless chamber of the boom cylinder needs to return oil, the first control valve can control the spring chamber of the first cone valve to unload, and the rodless chamber of the boom cylinder... After the oil enters the second port, it can open the valve core, flow to the first port, and then return through the boom main control valve. When the boom main control valve is in the neutral position, the first control valve can control the spring chamber of the first cone valve to connect with the second port. The oil in the rodless chamber of the boom cylinder enters the spring chamber of the first cone valve. The oil pressure in the spring chamber plus the force of the spring is greater than the force of the oil entering the second port on the valve core, so the valve core cannot open. This can maintain the position of the boom and prevent the boom from descending under the action of gravity. The excavator drive system of this utility model includes a second anti-sinking valve group in the stick drive unit. The second control valve can control the opening and closing of the second cone valve by controlling the oil pressure in the spring chamber of the second cone valve. When the rod chamber of the stick cylinder needs to return oil, the second control valve can control the spring chamber of the second cone valve to unload. After the oil in the rod chamber of the stick cylinder enters the fourth oil port, it can open the valve core, flow to the third oil port, and then return oil through the stick main control valve. When the stick main control valve is in the neutral position, the second control valve can control the spring chamber of the second cone valve to connect with the fourth oil port. The oil in the rod chamber of the stick cylinder enters the spring chamber of the second cone valve. The oil pressure in the spring chamber plus the force of the spring is greater than the force of the oil entering the fourth oil port on the valve core, so the valve core cannot open. This can maintain the position of the stick and prevent the stick from descending under the action of gravity. The excavator drive system of this utility model includes a regeneration oil circuit in the stick drive unit, which can regenerate and reuse the return oil from the rod chamber of the stick cylinder. Specifically, the regeneration oil circuit includes a first oil circuit and a second oil circuit connected in parallel. A first valve is installed on the first oil circuit and a second valve is installed on the second oil circuit. By controlling the opening degree of the first valve and the second valve, the flow rate of the regenerated oil can be controlled, which facilitates accurate control of the stick movement. Attached Figure Description

[0016] Figure 1 This is a system schematic diagram of the excavator drive system of this utility model; Figure 2 This is a hydraulic schematic diagram of the boom drive unit; Figure 3 This is a hydraulic schematic diagram of the boom drive unit; Figure 4 This is a schematic diagram of the regenerative flow control principle of the boom drive unit. Figure 5 Hydraulic schematic diagram of the travel-bucket drive unit; In the diagram: 1-Slewing drive unit; 11-Slewing motor; 12-Reducer; 2-Boom drive unit; 21-First pump; 22-Boom control valve; 221-Boom main control valve; 2211-One-way oil circuit; 222-First anti-settlement valve assembly; 2221-First cone valve; 2222-First control valve; 23-Boom cylinder; 3-Stick drive unit; 31-Second pump; 32-Stick control valve; 321-Stick main control valve; 322-Second anti-settlement valve assembly; 3221-Second cone valve; 3222-Second... Control valve; 323-Regeneration oil circuit; 3231-First oil circuit; 3232-Second oil circuit; 3233-First valve; 3234-Second valve; 33-Stick cylinder; 4-Travel-bucket drive unit; 41-Third pump; 42-Fourth pump; 43-Travel control valve; 431-Left travel control valve; 432-Right travel control valve; 44-Bucket control valve; 45-Travel actuator; 46-Bucket cylinder; 47-Distribution valve; 5-Pump motor; 6-One-to-two reducer; 7-Power supply; 8-Controller; 9-Pilot pump. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0018] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0019] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0020] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms 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 on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.

[0021] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0022] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0023] like Figure 1-5 As shown, this embodiment proposes an excavator drive system, including a swing drive unit 1, a boom drive unit 2, a stick drive unit 3, and a travel-bucket drive unit 4. The swing drive unit 1, boom drive unit 2, and stick drive unit 3 are independent drive units. The travel-bucket drive unit 4 includes two pumps and a distribution valve 47. The distribution valve 47 distributes the pressurized oil pumped out. When traveling and bucketing actions are performed simultaneously, the distribution valve 47 controls one pump to supply oil to the travel system and the other pump to supply oil to the bucket. Thus, under any working condition, load coupling will not occur.

[0024] like Figure 1 As shown, the rotary drive unit 1 includes a rotary motor 11 and a reducer 12. The rotary motor 11 drives the reducer 12 to directly mechanically drive the rotary mechanism to perform rotary action.

[0025] like Figure 1 As shown, the boom drive unit 2 includes a first pump 21, a boom control valve 22, and a boom cylinder 23. The first pump 21 provides pressurized oil to the boom control valve 22, the boom control valve 22 controls the oil flow in and out of the boom cylinder 23, and the boom cylinder 23 drives the boom to move.

[0026] like Figure 2 As shown, the boom control valve 22 includes a boom main control valve 221, which can be configured as a three-position six-way valve. The boom main control valve 221 has an oil inlet, an oil return port, two working oil ports, and an oil outlet. There are two oil inlets, and the pump outlet P1 of the first pump 21 is connected to both oil inlets. The oil return port and the oil outlet are both connected to the oil return tank. The two working oil ports are connected to the rod chamber and the rodless chamber of the boom cylinder 23, respectively. When the boom main control valve 221 is in the neutral position, one oil inlet is connected to the oil outlet, and the other oil ports are not connected. The pressurized oil pumped by the first pump 21 flows to the oil outlet and enters the oil return tank for return oil. When the boom main control valve 221 is in one of the two working positions, the oil inlet and the oil outlet are disconnected. The boom main control valve 221 controls one of the rod chamber and the rodless chamber of the boom cylinder 23 to receive oil, and the other chamber to receive oil.

[0027] As a preferred embodiment, the boom main control valve 221 is further provided with a one-way oil passage 2211. When the boom main control valve 221 is in the working position where oil is introduced into the rod chamber and returned to the rodless chamber of the boom cylinder 23, the returned oil from the rodless chamber of the boom cylinder 23 can enter the rod chamber of the boom cylinder 23 through the one-way oil passage 2211, realizing the regeneration and reuse of the returned oil. Preferably, the one-way oil passage 2211 is provided on the valve core of the boom main control valve 221, and a one-way valve structure is provided on the one-way oil passage 2211 to control the one-way flow of oil.

[0028] As a preferred embodiment, the boom control valve 22 further includes a first anti-settlement valve assembly 222, which is disposed in the oil line from the boom main control valve 221 to the rodless chamber of the boom cylinder 23. The first anti-settlement valve assembly 222 includes a first cone valve 2221 and a first control valve 2222. The first cone valve 2221 has a first oil port and a second oil port. The first oil port is connected to a working oil port of the boom main control valve 221, and the second oil port is connected to the rodless chamber of the boom cylinder 23. The first control valve 2222 controls the oil pressure in the spring chamber of the first cone valve 2221. Specifically, the first control valve 2222 controls the connection between the spring chamber of the first cone valve 2221 and the second oil port, or controls the unloading of the spring chamber of the first cone valve 2221. The first control valve 2222 can be a two-position three-way valve. In the initial state, the first control valve 2222 can be in the first working position under the action of the elastic element, so that the spring chamber of the first cone valve 2221 is connected to the second oil port. When the boom stops working, the oil in the rodless chamber of the boom cylinder 23 can enter the first cone valve 2221 through the second oil port, and at the same time enter the spring chamber of the first cone valve 2221 through the first control valve 2222. The valve core of the first cone valve 2221 is pressed tight under the action of the spring and the oil pressure in the rodless chamber, blocking the connection between the second oil port and the first oil port. The oil in the rodless chamber of the boom cylinder 23 cannot flow out, which can achieve anti-settlement. Function: When the rodless chamber of the boom cylinder 23 needs normal oil return, a control signal can be introduced to the first control valve 2222 to switch the first control valve 2222 to the second working position. At this time, the spring chamber of the first cone valve 2221 is depressurized and is in a low-pressure state. The oil in the rodless chamber of the boom cylinder 23 enters the first cone valve 2221 through the second oil port, pushing the valve core of the first cone valve 2221 to open. The second oil port and the first oil port are connected. The oil in the rodless chamber of the boom cylinder 23 can flow through the first cone valve 2221 to the boom main control valve 221. Part of it returns oil, and part of it is recycled through the one-way flow oil circuit 2211.

[0029] As a preferred technical solution in this embodiment, the boom main control valve 221 and the first control valve 2222 can both be electrically controlled valves, which can be switched under the control of electrical signals.

[0030] like Figure 1 As shown, the stick drive unit 3 includes a second pump 31, a stick control valve 32, and a stick cylinder 33. The second pump 31 provides pressurized oil to the stick control valve 32, the stick control valve 32 controls the oil inlet and outlet of the stick cylinder 33, and the stick cylinder 33 drives the stick to move.

[0031] like Figure 3As shown, the boom control valve 32 includes a boom main control valve 321, which can be configured as a three-position six-way valve. The boom main control valve 321 has an oil inlet, an oil return port, two working oil ports, and an oil outlet. There are two oil inlets, and the pump outlet P2 of the second pump 31 is connected to both oil inlets. The oil return port and the oil outlet are both connected to the oil return tank. The two working oil ports are respectively connected to the rod chamber and the rodless chamber of the boom cylinder 33. When the boom main control valve 321 is in the neutral position, one oil inlet is connected to the oil outlet, and the other ports are not connected. The pressurized oil pumped by the second pump 31 flows to the oil outlet and enters the oil return tank for return oil. When the boom main control valve 321 is in either of the two working positions, the oil inlet and the oil outlet are disconnected. The boom main control valve 321 controls one of the rod chambers and the rodless chamber of the boom cylinder 33 to receive oil, while the other chamber receives oil.

[0032] As a preferred embodiment, the boom control valve 32 further includes a second anti-settlement valve assembly 322, which is disposed in the oil line from the boom main control valve 321 to the rod chamber of the boom cylinder 33. The second anti-settlement valve assembly 322 includes a second cone valve 3221 and a second control valve 3222. The second cone valve 3221 has a third port and a fourth port. The third port is connected to a working port of the boom main control valve 321, and the fourth port is connected to the rod chamber of the boom cylinder 33. The second control valve 3222 controls the oil pressure in the spring chamber of the second cone valve 3221. Specifically, the second control valve 3222 controls the connection between the spring chamber of the second cone valve 3221 and the fourth port, or controls the unloading of the spring chamber of the second cone valve 3221. The second control valve 3222 can be a two-position three-way valve. Initially, under the action of the elastic element, the second control valve 3222 is in the first working position, connecting the spring chamber of the second cone valve 3221 with the second oil port. When the boom stops working, the oil in the rod chamber of the boom cylinder 33 can enter the second cone valve 3221 through the fourth oil port, and simultaneously enter the spring chamber of the second cone valve 3221 through the second control valve 3222. The valve core of the second cone valve 3221 is pressed shut by the spring and the oil pressure in the rod chamber, blocking the connection between the fourth and third oil ports. The oil in the rod chamber of the boom cylinder 33... The oil cannot flow out, thus preventing sedimentation. When the rod chamber of the boom cylinder 33 needs normal oil return, a control signal can be introduced to the second control valve 3222 to switch it to the second working position. At this time, the spring chamber of the second cone valve 3221 is depressurized and is in a low-pressure state. The oil in the rod chamber of the boom cylinder 33 enters the second cone valve 3221 through the fourth oil port, pushing the valve core of the second cone valve 3221 to open. The fourth oil port and the third oil port are connected, and the oil in the rod chamber of the boom cylinder 33 can flow through the second cone valve 3221 to the boom main control valve 321 for oil return.

[0033] As a preferred embodiment, the boom control valve 32 further includes a regeneration oil passage 323. The return oil from the rod chamber of the boom cylinder 33 can enter the rodless chamber of the boom cylinder 33 via the regeneration oil passage 323, achieving regeneration and reuse. Preferably, the regeneration oil passage 323 has an adjustable regeneration flow rate. Specifically, the regeneration oil passage 323 includes a first oil passage 3231 and a second oil passage 3232 connected in parallel. The first oil passage 3231 connects the third oil port of the second cone valve 3221 and the rodless chamber of the boom cylinder 33; the second oil passage 3232 connects the third oil port and the return oil port of the second cone valve 3221. A first valve 3233 is provided on the first oil passage 3231, controlling the opening degree of the first oil passage 3231; a second valve 3234 is provided on the second oil passage 3232, controlling the opening degree of the second oil passage 3232.

[0034] As a preferred embodiment, the boom main control valve 321, the second control valve 3222, the first valve 3233, and the second valve 3234 are all electrically controlled valves, which can be switched under the control of electrical signals. The first valve 3233 and the second valve 3234 are spool valves, which can slide to control the opening of their respective oil circuits under the control of electrical signals.

[0035] like Figure 1 As shown, the travel-bucket drive unit 4 includes a third pump 41, a fourth pump 42, a travel control valve 43, a bucket control valve 44, a travel actuator 45, a bucket cylinder 46, and a distribution valve 47. The third pump 41 and the fourth pump 42 provide pressurized oil to the travel control valve 43 and the bucket control valve 44. The travel control valve 43 controls the oil flow of the travel actuator 45, and the travel actuator 45 drives the travel action. The bucket control valve 44 controls the oil flow of the bucket cylinder 46, and the bucket cylinder 46 drives the bucket action.

[0036] like Figure 5 As shown, the travel control valve 43 includes a left travel control valve 431 and a right travel control valve 432, and the travel actuator 45 includes a left travel actuator and a right travel actuator. The left travel control valve 431 controls the oil inlet and outlet of the left travel actuator, and the left travel actuator drives the left travel action; the right travel control valve 432 controls the oil inlet and outlet of the right travel actuator, and the right travel actuator drives the right travel action.

[0037] As a preferred embodiment, the distribution valve 47 has oil ports p3, p4, a, and b. Oil port p3 is connected to the pump outlet P3 of the third pump 41, oil port p4 is connected to the pump outlet P4 of the fourth pump 42, oil port a is connected to the bucket control valve 44, and oil port b is connected to the left travel control valve 431. The third pump 41 directly supplies oil to the right travel control valve 432, and under the control of the distribution valve 47, the third pump 41 supplies oil to the bucket control valve 44 or the left travel control valve 431; the fourth pump 42, under the control of the distribution valve 47, supplies oil to the left travel control valve 431 or the bucket control valve 44. Specifically, in this embodiment, the distribution valve 47 is a two-position four-way valve. When the distribution valve 47 is in its initial first position, the distribution valve 47 controls port p3 to connect with port a and port p4 to connect with port b. That is, the third pump 41 simultaneously supplies oil to the right travel control valve 432 and the bucket control valve 44, and the fourth pump 42 supplies oil to the right travel control valve 431. In this position, the travel control valve 43 and the bucket control valve 44 can be controlled to perform only the travel action or only the bucket action. When the distribution valve 47 switches to the second position, the distribution valve 47 controls port p3 to connect with port b and port p4 to connect with port a. That is, the third pump 41 simultaneously supplies oil to the left travel control valve 431 and the right travel control valve 432, and the fourth pump 42 supplies oil to the bucket control valve 44. In this position, the travel and bucket actions can be performed simultaneously. The third pump 41 is used to drive the travel, and the fourth pump 42 is used to drive the bucket action. There is no coupling.

[0038] As a preferred technical solution in this embodiment, the left travel control valve 431, the right travel control valve 432 and the bucket control valve 44 can all be set as three-position valves. When the control valve is in the middle position, the pressure oil will not enter the corresponding travel actuator 45 or the bucket cylinder 46. When the control valve is in the two working positions, it can control the corresponding travel actuator 45 or the bucket cylinder 46 to work.

[0039] As a preferred technical solution in this embodiment, the left travel control valve 431, the right travel control valve 432, the bucket control valve 44, and the distribution valve 47 can all be electrically controlled valves, which can be switched under the control of electrical signals.

[0040] like Figure 1 As shown, the first pump 21, the second pump 31, the third pump 41, and the fourth pump 42 are all driven by the same pump motor 5. Specifically, the pump motor 5 drives a one-to-two reducer 6, which has two output terminals, namely a first output terminal and a second output terminal. The first output terminal drives the first pump 21 and the second pump 31; the second output terminal drives the third pump 41 and the fourth pump 42.

[0041] As a preferred technical solution of this embodiment, it also includes a pilot pump 9, and the first output end of the pump motor 5 drives the pilot pump 9, and the pilot pump 9 pumps out oil for use as pilot oil.

[0042] The excavator drive system in this embodiment also includes a power supply 7 and a controller 8. The power supply 7 supplies power to the pump motor 5 and the swing motor 11, and the controller 8 controls the drive of the swing motor 11 and the pump motor 5. The power supply 7 is optional, but not limited to, a battery. The controller 8 can be an all-in-one controller.

[0043] As a preferred technical solution in this embodiment, the controller 8 can also control the state of each control valve according to the execution signal. For example... Figure 4 As shown, controller 8 achieves precise control of the return oil volume and regeneration volume of the rod chamber of boom cylinder 33. The control logic is as follows: controller 8 can collect external conditions such as rod chamber pressure, rodless chamber pressure, and oil temperature of boom cylinder 33 in real time; controller 8 confirms the target speed and target rod chamber pressure based on the handle signal, and confirms the corresponding control flow rate based on the target speed; at different speeds, an appropriate rod chamber pressure is set to ensure the smoothness of the operation. Two control areas can be formed through the openings of the first valve 3233 and the second valve 3234, and both control areas follow the pressure-flow formula:

[0044] In the formula: Q represents flow rate; Indicates the flow coefficient; A represents the valve core control area; This indicates the pressure difference across the valve core; This indicates the oil density. Based on the target flow rate and pressure requirements, the control areas of the first valve 3233 and the second valve 3234 can be obtained. Then, based on the area curves of the valve core openings of the first valve 3233 and the second valve 3234, the target displacements of the first valve 3233 and the second valve 3234 can be obtained.

[0045] Based on the above technical solution, the excavator distributed drive system of this embodiment can drive the boom, stick, bucket, and travel movements of the excavator, and even with combined movements, there will be no load coupling problem. This embodiment uses only one pump motor 5 and one rotary motor 11 to drive multiple actuators, effectively controlling the number of components, reducing size, and lowering cost.

[0046] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. An excavator drive system, characterized in that, include: The rotary drive unit (1) includes a rotary motor (11) that mechanically drives the rotary motion. The boom drive unit (2) includes a first pump (21), a boom control valve (22) and a boom cylinder (23). The boom drive unit (3) includes a second pump (31), a boom control valve (32), and a boom cylinder (33). The travel-bucket drive unit (4) includes a third pump (41), a fourth pump (42), a travel control valve (43), a bucket control valve (44), a travel actuator (45), a bucket cylinder (46), and a distribution valve (47). When the travel and bucket actions are performed simultaneously, the distribution valve (47) controls the third pump (41) to supply oil to the travel control valve (43), and the fourth pump (42) to supply oil to the bucket control valve (44). The first pump (21), the second pump (31), the third pump (41) and the fourth pump (42) are driven by the same pump motor (5).

2. The excavator drive system according to claim 1, characterized in that, The pump motor (5) drives a one-to-two reducer (6), the first output end of the one-to-two reducer (6) drives the first pump (21) and the second pump (31), and the second output end of the one-to-two reducer (6) drives the third pump (41) and the fourth pump (42).

3. An excavator drive system according to any one of claims 1-2, characterized in that, It also includes a power supply (7) and a controller (8), the power supply (7) providing electrical energy to the rotary motor (11) and the pump motor (5), and the controller (8) driving the rotary motor (11) and the pump motor (5).

4. The excavator drive system according to claim 1, characterized in that, The walking actuator (45) includes a left walking actuator and a right walking actuator, and the walking control valve (43) includes a left walking control valve (431) and a right walking control valve (432). The left walking control valve (431) controls the oil inlet and outlet of the left walking actuator, and the right walking control valve (432) controls the oil inlet and outlet of the right walking actuator.

5. The excavator drive system according to claim 4, characterized in that, The third pump (41) supplies oil to the distribution valve (47) and a travel control valve (43), and the fourth pump (42) supplies oil to the distribution valve (47). One working port of the distribution valve (47) is connected to another travel control valve (43), and one working port of the distribution valve (47) is connected to the bucket control valve (44). When the distribution valve (47) is in the first position, the third pump (41) supplies oil to one travel control valve (43), and the fourth pump (42) supplies oil to the other travel control valve (43) through the distribution valve (47). When the distribution valve (47) is in the second position, the third pump (41) supplies oil to both travel control valves (43) at the same time, and the fourth pump (42) supplies oil to the bucket control valve (44) through the distribution valve (47).

6. The excavator drive system according to claim 1, characterized in that, The boom control valve (22) includes a boom main control valve (221) and a one-way connecting oil circuit (2211). When the boom main control valve (221) controls the rod chamber of the boom cylinder (23) to receive oil and the rodless chamber to return oil, the return oil from the rodless chamber can flow into the rod chamber of the boom cylinder (23) through the one-way connecting oil circuit (2211).

7. An excavator drive system according to claim 6, characterized in that, The boom drive unit (2) further includes a first anti-settlement valve group (222). The first anti-settlement valve group (222) is located on the oil line between the boom main control valve (221) and the rodless chamber of the boom cylinder (23). The first anti-settlement valve group (222) includes a first cone valve (2221) and a first control valve (2222). The first cone valve (2221) has a first oil port and a second oil port. The first oil port is connected to the boom main control valve (221), and the second oil port is connected to the rodless chamber of the boom cylinder (23). The first control valve (2222) controls the spring chamber of the first cone valve (2221) to connect with the second oil port or to unload the spring chamber of the first cone valve (2221).

8. The excavator drive system according to claim 1, characterized in that, The boom control valve (32) includes a boom main control valve (321) and a second anti-settlement valve group (322). The second anti-settlement valve group (322) is located on the oil line between the boom main control valve (321) and the rod chamber of the boom cylinder (33). The second anti-settlement valve group (322) includes a second cone valve (3221) and a second control valve (3222). The second cone valve (3221) has a third oil port and a fourth oil port. The third oil port is connected to the boom main control valve (321), and the fourth oil port is connected to the rod chamber of the boom cylinder (33). The second control valve (3222) controls the spring chamber of the second cone valve (3221) to connect with the fourth oil port or to unload the spring chamber of the second cone valve (3221).

9. An excavator drive system according to claim 8, characterized in that, It also includes a regeneration oil circuit (323), through which the return oil from the rod chamber of the boom cylinder (33) can enter the rodless chamber of the boom cylinder (33) via the regeneration oil circuit (323), and the regeneration oil circuit (323) can adjust the flow rate of the return oil from the rod chamber of the boom cylinder (33) into the rodless chamber.

10. An excavator drive system according to claim 9, characterized in that, The regeneration oil circuit (323) includes a first oil circuit (3231) and a second oil circuit (3232) arranged in parallel. The first oil circuit (3231) is connected to the third oil port and the rodless chamber of the boom cylinder (33). A first valve (3233) is provided on the first oil circuit (3231). The second oil circuit (3232) is connected to the third oil port and the return oil port. A second valve (3234) is provided on the second oil circuit (3232). The first valve (3233) and the second valve (3234) control the opening degree of the oil circuit.

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