Travel power system of electric loader with dual motor input and control method thereof

Abstract

The present invention discloses a walking power system of an electric loader with dual motor input and a control method thereof, comprising a drive motor and a gearbox, wherein the drive motor is connected to the gearbox input shaft; the drive motor comprises a main drive motor and an auxiliary drive motor, and the gearbox comprises a main drive input shaft, an auxiliary drive input shaft, an intermediate shaft and an output shaft, wherein the main drive motor is connected to the main drive input shaft, and the auxiliary drive motor is connected to the auxiliary drive input shaft; the main drive input shaft is connected to the output shaft through a gear transmission pair, and the intermediate shaft is respectively connected to the auxiliary drive input shaft and the output shaft through a gear transmission pair. Beneficial effects: Under light load conditions, the present invention enables only the main drive motor to be enabled, which can save more energy and improve the endurance of the vehicle; through the cooperation of different transmission routes of the two motors, the loader can obtain greater traction; the main controller selects the corresponding control strategy according to the current working conditions to realize automatic control of the gearbox.

Description

Technical Field

[0001] The present invention relates to a traveling power system of an engineering machine and a control method thereof, and in particular to a traveling power system of an electric loader with dual motor input and a control method thereof, and belongs to the technical field of engineering machinery. Background Art

[0002] Traditional construction machinery mainly uses diesel as fuel, which increases environmental pollution and wastes energy seriously. In order to improve this situation, many construction machinery manufacturers are now engaged in the development of new energy vehicles, which is of great significance for reducing environmental pollution and saving energy. As one of the most widely used equipment in construction machinery, many host manufacturers have launched their own pure electric loader products.

[0003] The driving and operation of pure electric loaders are powered by onboard power batteries, which are output through electric motors. The travel system of pure electric loaders uses electric motors and gearboxes as power output to drive the entire vehicle. Currently, pure electric loaders usually use a single motor and a gearbox with a single power input as power output to drive the entire vehicle.

[0004] The loader is in heavy-load condition only when shoveling, which requires a large traction force; the other conditions are light-load conditions, which only require a small traction force; the loader is in heavy-load condition for a short time during the whole operation, and most of the time is in light-load condition. However, in order to meet the needs of heavy-load conditions, the drive motor must be selected with a high-power motor that meets the needs of heavy-load conditions; choosing a high-power motor will cause problems such as high cost of the whole machine, large current and low motor efficiency. Summary of the invention

[0005] Purpose of the invention: The purpose of the present invention is to provide a dual-motor input electric loader travel power system and a control method thereof in view of the problems existing in the prior art. The dual-motor structure can select two drive motors with smaller power, which can effectively improve the drive efficiency of the drive motor and reduce the cost.

[0006] Technical solution: A walking power system of an electric loader with dual motor inputs, comprising a drive motor and a gearbox, wherein the drive motor is connected to the gearbox input shaft; the drive motor comprises a main drive motor and an auxiliary drive motor, the gearbox comprises a main drive input shaft, an auxiliary drive input shaft, an intermediate shaft and an output shaft, the main drive motor is connected to the main drive input shaft, and the auxiliary drive motor is connected to the auxiliary drive input shaft; the main drive input shaft and the output shaft are connected via a gear transmission pair, the intermediate shaft is located between the auxiliary drive input shaft and the output shaft, and the intermediate shaft is respectively connected to the auxiliary drive input shaft and the output shaft via a gear transmission pair.

[0007] The present invention provides power to the output shaft through the main drive motor and the auxiliary drive motor. After the main drive motor and the auxiliary drive motor are combined, the needs of the loader's short-term heavy-load conditions can be met, and the main drive motor can meet the needs of most of the loader's light-load conditions; under light-load conditions, only activating the main drive motor can be more energy-efficient and improve the endurance of the entire vehicle.

[0008] Preferably, in order to simplify the structure of the gearbox, the main drive input shaft is provided with an input shaft gear, the output shaft is fixedly installed with an output shaft gear, the auxiliary drive input shaft is provided with an auxiliary drive shaft gear, and the intermediate shaft is provided with a first intermediate shaft gear and a second intermediate shaft gear respectively; the output shaft gear is meshed with the input shaft gear and the second intermediate shaft gear at the same time, the first intermediate shaft gear and the second intermediate shaft gear are coaxial, and the first intermediate shaft gear is meshed with the auxiliary drive shaft gear; a main drive clutch C1 is provided between the input shaft gear and the main drive input shaft. Through reliable gear pair transmission, power can be stably and reliably transmitted, and the main drive clutch C1 can cut off the power transmission when starting and stopping, which is safer and more energy-saving; through the cooperation of different transmission routes of the two motors, the loader can obtain greater traction.

[0009] Preferably, in order to achieve coupling of the auxiliary drive motor in heavy-load conditions, the auxiliary drive shaft gear is fixedly connected to the auxiliary drive input shaft; the second gear of the intermediate shaft is fixedly mounted on the intermediate shaft, and an auxiliary transmission clutch C2 is provided between the first gear of the intermediate shaft and the intermediate shaft.

[0010] Preferably, in order to achieve coupling of the auxiliary drive motor in heavy-load conditions, the first intermediate shaft gear and the second intermediate shaft gear are fixedly connected to the intermediate shaft respectively, and an auxiliary transmission clutch C2 is provided between the auxiliary drive shaft gear and the auxiliary drive input shaft.

[0011] Preferably, in order to judge the working condition of the loader and realize automatic gear shifting of the gearbox, a main drive speed sensor B1 for measuring the speed of the main drive motor and an output speed sensor B3 for measuring the speed of the output shaft are provided in the gearbox. By collecting the speed of the main drive motor and the speed of the output shaft, a basis is provided for judging the working condition of the loader and for coupling the auxiliary drive motor.

[0012] Preferably, in order to realize automatic gear shifting of the gearbox, an auxiliary drive speed sensor B2 for measuring the speed of the auxiliary drive motor is provided in the gearbox. The auxiliary drive speed sensor B2 can measure the speed of the auxiliary drive motor, providing a basis for coupling the auxiliary drive motor under heavy load conditions.

[0013] Preferably, in order to realize automatic gear shifting of the gearbox, it also includes a main controller, a gear selector and an accelerator pedal displacement sensor, the gear selector sends a control signal to the main controller, and the signals of the main drive speed sensor B1, the output speed sensor B3, the auxiliary drive speed sensor B2 and the accelerator pedal displacement sensor are simultaneously transmitted to the main controller; the main controller controls the main drive clutch C1 and the auxiliary drive clutch C2 of the gearbox as well as the main drive motor and the auxiliary drive motor respectively. The driver sends a vehicle driving instruction through the gear selector, the main controller judges the current working condition through the signals of the accelerator pedal displacement sensor and the output speed sensor B3, and the main controller selects the corresponding control strategy according to the current working condition, and the main controller controls the separation or engagement of the main drive clutch C1 and the auxiliary drive clutch C2 of the gearbox respectively, and controls the speed of the auxiliary drive motor to realize the switching between the control strategies, thereby realizing automatic control of the gearbox.

[0014] A control method for a walking power system of an electric loader with dual motor inputs comprises the following steps:

[0015] Step 1: Initial state: the gearbox is in neutral, and the main transmission clutch C1 and the auxiliary transmission clutch C2 are released at the same time;

[0016] Step 2: The gear selector sends a control command to start the main drive motor. The main controller determines the current working condition based on the signals of the accelerator pedal displacement sensor and the output speed sensor B3. When the working condition is light load, it goes to step 3; when the working condition is heavy load, it goes to step 4.

[0017] Step 3, light load control strategy: the main drive clutch C1 is engaged, and the auxiliary drive clutch C2 is disengaged, and the power output by the main drive motor is transmitted to the output shaft through the main drive input shaft, the main drive clutch C1, the input shaft gear and the output shaft gear in sequence;

[0018] Step 4, heavy load control strategy: the main transmission clutch C1 is engaged first, and the power output by the main drive motor is transmitted to the output shaft gear through the main drive input shaft, the main transmission clutch C1 and the input shaft gear in sequence; after the main controller adjusts the speed of the auxiliary drive motor to match the speed of the output shaft, the auxiliary transmission clutch C2 is engaged, and the power output by the auxiliary drive motor is transmitted to the output shaft gear through the auxiliary drive input shaft, the auxiliary drive shaft gear, the first intermediate shaft gear, the intermediate shaft and the second intermediate shaft gear in sequence, and the converged power is output by the output shaft;

[0019] Step 5: Automatic shifting: The main controller determines the change of the working condition according to the signals of the output speed sensor B3 and the accelerator pedal displacement sensor; and switches the control strategy in real time according to the current working condition;

[0020] Step 6: Stop: The gear position of the transmission returns to neutral.

[0021] The control method of the present invention realizes automatic gear shifting of the transmission according to changes in operating conditions during the process from vehicle starting to vehicle driving.

[0022] Optimum option, in order to accurately judge the current working condition, first, set the judgment parameters of the main controller: combine the displacement parameters of the accelerator pedal displacement sensor and the output speed parameters of the output shaft to divide zone I into the heavy load zone, zone II into the transition zone, and zone III into the light load zone;

[0023] Then, the main controller collects data: according to the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft measured by the output speed sensor B3;

[0024] Finally, the main controller determines the operating condition: when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft measured by the output speed sensor B3 are within the range of Zone I set by the main controller, the main controller determines it to be a heavy-load condition, and the main transmission clutch C1 and the auxiliary transmission clutch C2 are engaged at the same time; when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft measured by the output speed sensor B3 are within the range of Zone II set by the main controller, the main controller determines it to be a transitional condition, and the main transmission clutch C1 and the auxiliary transmission clutch C2 maintain their original states; when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft measured by the output speed sensor B3 are within the range of Zone III set by the main controller, the main controller determines it to be a light-load condition, and the main transmission clutch C1 is engaged, while the auxiliary transmission clutch C2 is disengaged.

[0025] Preferably, in order to achieve power coupling of the auxiliary drive motor, the method for matching the rotation speed of the auxiliary drive motor with the output shaft rotation speed in step 4 is:

[0026] Get the transmission ratio i from the main drive motor to the output shaft M1 =Z5 / Z4;

[0027] Get the transmission ratio i from the auxiliary drive motor to the output shaft M2 =(Z2 / Z1)×(Z5 / Z3);

[0028] Wherein, Z1 is the number of teeth of the auxiliary drive shaft gear, Z2 is the number of teeth of the first gear of the intermediate shaft, Z3 is the number of teeth of the second gear of the intermediate shaft, Z4 is the number of teeth of the main drive shaft gear, and Z5 is the number of teeth of the output shaft gear;

[0029] The main drive speed sensor B1 measures the speed of the main drive motor ;

[0030] According to the coupling principle between the main drive motor and the auxiliary drive motor,

[0031] ;

[0032] Calculated value of auxiliary drive motor speed ;

[0033] The main controller adjusts the measured speed value of the auxiliary drive motor to the calculated speed value The auxiliary drive speed sensor B2 measures the speed value of the auxiliary drive motor. When the speed value is equal to the speed calculation value, the auxiliary transmission clutch C2 is engaged.

[0034] Beneficial effects: The present invention provides power to the output shaft through the main drive motor and the auxiliary drive motor. After the main drive motor and the auxiliary drive motor are combined, the needs of the loader under short-term heavy-load conditions can be met, and the main drive motor can meet the needs of most light-load conditions of the loader; only enabling the main drive motor under light-load conditions can be more energy-efficient and improve the endurance of the whole vehicle; through the coordination of different transmission routes of the two motors, the loader can obtain greater traction; the driver issues a vehicle driving command through the gear selector, and the main controller determines the current working condition through the signals of the accelerator pedal displacement sensor and the main drive speed sensor B1. The main controller selects the corresponding control strategy according to the current working condition, and the main controller controls the separation or engagement of the main drive clutch C1 and the auxiliary drive clutch C2 of the gearbox respectively, and controls the speed of the auxiliary drive motor to realize the switching between control strategies, thereby realizing automatic control of the gearbox. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0036] Figure 1 It is a structural principle diagram of the first embodiment of the present invention;

[0037] Figure 2 is a structural principle diagram of a second embodiment of the present invention;

[0038] Figure 3 It is the control principle diagram of the present invention;

[0039] Figure 4 It is a schematic diagram of the automatic shifting rule of the present invention. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the description of the present invention, it is necessary to understand that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0042] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0043] Embodiment 1

[0044] like Figure 1 As shown, a dual-motor input electric loader travel power system includes a drive motor 1 and a gearbox 2, wherein the drive motor 1 is connected to the input shaft of the gearbox 2; the drive motor 1 includes a main drive motor 11 and an auxiliary drive motor 12, the gearbox 2 includes a main drive input shaft 21, an auxiliary drive input shaft 22, an intermediate shaft 23 and an output shaft 24, the main drive motor 11 is connected to the main drive input shaft 21, and the auxiliary drive motor 12 is connected to the auxiliary drive input shaft 22; the main drive input shaft 21 is connected to the output shaft 24 through a gear transmission pair, the intermediate shaft 23 is located between the auxiliary drive input shaft 22 and the output shaft 24, and the intermediate shaft 23 is respectively connected to the auxiliary drive input shaft 22 and the output shaft 24 through a gear transmission pair.

[0045] The present invention provides power to the output shaft 24 through the main drive motor 11 and the auxiliary drive motor 12. After the main drive motor 11 and the auxiliary drive motor 12 are combined, the needs of the loader's short-term heavy-load conditions can be met, and the main drive motor 11 can meet the needs of most of the loader's light-load conditions; under light-load conditions, only activating the main drive motor 11 can be more energy-efficient and improve the endurance of the entire vehicle.

[0046] In order to simplify the structure of the gearbox 2, a main drive shaft gear 211 is provided on the main drive input shaft 21, an output shaft gear 241 is fixedly mounted on the output shaft 24, an auxiliary drive shaft gear 221 is provided on the auxiliary drive input shaft 22, and a first intermediate shaft gear 231 and a second intermediate shaft gear 232 are provided on the intermediate shaft 23; the output shaft gear 241 is meshed with the main drive shaft gear 211 and the second intermediate shaft gear 232 at the same time, the first intermediate shaft gear 231 and the second intermediate shaft gear 232 are coaxial, and the first intermediate shaft gear 231 is meshed with the auxiliary drive shaft gear 221; a main drive clutch C125 is provided between the main drive shaft gear 211 and the main drive input shaft 21. Through reliable gear pair transmission, power can be stably and reliably transmitted, and the main drive clutch C125 can cut off the power transmission when starting and stopping, which is safer and more energy-saving.

[0047] In order to achieve the coupling of the auxiliary drive motor 12 under heavy load conditions, the auxiliary drive shaft gear 221 is fixedly connected to the auxiliary drive input shaft 22; the intermediate shaft second gear 232 is fixedly installed on the intermediate shaft 23, and an auxiliary transmission clutch C226 is provided between the intermediate shaft first gear 231 and the intermediate shaft 23.

[0048] In order to realize the judgment of the working condition of the loader and realize the automatic shifting of the gearbox 2, the gearbox 2 is provided with a main drive speed sensor B13 for measuring the speed of the main drive motor 11 and an output speed sensor B34 for measuring the speed of the output shaft 24. By collecting the speed of the main drive motor 11 and the speed of the output shaft 24, a basis is provided for judging the working condition of the loader and for coupling the auxiliary drive motor 12.

[0049] In order to realize automatic shifting of the gearbox 2, an auxiliary drive speed sensor B25 for measuring the speed of the auxiliary drive motor 12 is provided in the gearbox 2. The auxiliary drive speed sensor B25 can measure the speed of the auxiliary drive motor 12, providing a basis for coupling the auxiliary drive motor under heavy load conditions.

[0050] Embodiment 2

[0051] like Figure 2As shown, a dual-motor input electric loader travel power system includes a drive motor 1 and a gearbox 2, wherein the drive motor 1 is connected to the input shaft of the gearbox 2; the drive motor 1 includes a main drive motor 11 and an auxiliary drive motor 12, the gearbox 2 includes a main drive input shaft 21, an auxiliary drive input shaft 22, an intermediate shaft 23 and an output shaft 24, the main drive motor 11 is connected to the main drive input shaft 21, and the auxiliary drive motor 12 is connected to the auxiliary drive input shaft 22; the main drive input shaft 21 is connected to the output shaft 24 through a gear transmission pair, the intermediate shaft 23 is located between the auxiliary drive input shaft 22 and the output shaft 24, and the intermediate shaft 23 is respectively connected to the auxiliary drive input shaft 22 and the output shaft 24 through a gear transmission pair.

[0052] The present invention provides power to the output shaft 24 through the main drive motor 11 and the auxiliary drive motor 12. After the main drive motor 11 and the auxiliary drive motor 12 are combined, the needs of the loader's short-term heavy-load conditions can be met, and the main drive motor 11 can meet the needs of most of the loader's light-load conditions; under light-load conditions, only activating the main drive motor 11 can be more energy-efficient and improve the endurance of the entire vehicle.

[0053] In order to simplify the structure of the gearbox 2, a main drive shaft gear 211 is provided on the main drive input shaft 21, an output shaft gear 241 is fixedly mounted on the output shaft 24, an auxiliary drive shaft gear 221 is provided on the auxiliary drive input shaft 22, and a first intermediate shaft gear 231 and a second intermediate shaft gear 232 are provided on the intermediate shaft 23; the output shaft gear 241 is meshed with the main drive shaft gear 211 and the second intermediate shaft gear 232 at the same time, the first intermediate shaft gear 231 and the second intermediate shaft gear 232 are coaxial, and the first intermediate shaft gear 231 is meshed with the auxiliary drive shaft gear 221; a main drive clutch C125 is provided between the main drive shaft gear 211 and the main drive input shaft 21. Through reliable gear pair transmission, power can be stably and reliably transmitted, and the main drive clutch C125 can cut off the power transmission when starting and stopping, which is safer and more energy-saving.

[0054] In order to achieve the coupling of the auxiliary drive motor 12 in heavy load conditions, the intermediate shaft first gear 231 and the intermediate shaft second gear 232 are fixedly connected to the intermediate shaft 23 respectively, and an auxiliary transmission clutch C226 is provided between the auxiliary drive shaft gear 221 and the auxiliary drive input shaft 22.

[0055] In order to realize the judgment of the working condition of the loader and the automatic shifting of the gearbox 2, the gearbox 2 is provided with a main drive speed sensor B13 for measuring the speed of the main drive motor 11 and an output speed sensor B34 for measuring the speed of the output shaft 24. By collecting the speed of the main drive motor 11 and the speed of the output shaft 24, a basis is provided for judging the working condition of the loader and for coupling the auxiliary drive motor 12.

[0056] In order to realize automatic shifting of the gearbox 2, an auxiliary drive speed sensor B25 for measuring the speed of the auxiliary drive motor 12 is provided in the gearbox 2. The auxiliary drive speed sensor B25 can measure the speed of the auxiliary drive motor 12, providing a basis for coupling the auxiliary drive motor under heavy load conditions.

[0057] like Figure 3 As shown, in order to realize the automatic shifting of the gearbox 2, it also includes a main controller, a gear selector and an accelerator pedal displacement sensor. The gear selector sends a control signal to the main controller, and the signals of the main drive speed sensor B13, the output speed sensor B34, the auxiliary drive speed sensor B25 and the accelerator pedal displacement sensor are simultaneously transmitted to the main controller; the main controller controls the main drive clutch C125 and the auxiliary drive clutch C226 of the gearbox 2, as well as the main drive motor 11 and the auxiliary drive motor 12. The driver sends a vehicle driving instruction through the gear selector, and the main controller judges the current working condition through the signals of the accelerator pedal displacement sensor and the output speed sensor B34. The main controller selects the corresponding control strategy according to the current working condition, and the main controller controls the separation or engagement of the main drive clutch C125 and the auxiliary drive clutch C226 of the gearbox respectively, and controls the speed of the auxiliary drive motor 12 to realize the switching between the control strategies, thereby realizing the automatic control of the gearbox 2.

[0058] A control method for a walking power system of an electric loader with dual motor inputs comprises the following steps:

[0059] Step 1: Initial state: the gear position of the gearbox 2 is in neutral, and the main transmission clutch C125 and the auxiliary transmission clutch C226 are released at the same time;

[0060] Step 2: The gear selector sends a control command to start the main drive motor 11, and the main controller determines the current working condition according to the signals of the accelerator pedal displacement sensor and the output speed sensor B34; when the working condition is light load, it goes to step 3; when the working condition is heavy load, it goes to step 4;

[0061] Step 3, light load control strategy: the main drive clutch C125 is engaged, and the auxiliary drive clutch C226 is disengaged, and the power output by the main drive motor 11 is transmitted to the output shaft 24 through the main drive input shaft 21, the main drive clutch C125, the main drive shaft gear 211 and the output shaft gear 241 in sequence;

[0062] Step 4, heavy load control strategy: the main transmission clutch C125 is engaged first, and the power output by the main drive motor 11 is transmitted to the output shaft gear 241 through the main drive input shaft 21, the main transmission clutch C125 and the main drive shaft gear 211 in sequence; after the main controller adjusts the speed of the auxiliary drive motor 12 to match the speed of the output shaft 24, the auxiliary transmission clutch C226 is engaged, and the power output by the auxiliary drive motor 12 is transmitted to the output shaft gear 241 through the auxiliary drive input shaft 22, the auxiliary drive shaft gear 221, the first intermediate shaft gear 231, the intermediate shaft 23 and the second intermediate shaft gear 232 in sequence, and the converged power is output by the output shaft 24;

[0063] Step 5: Automatic shifting: The main controller determines the change of the working condition according to the signals of the output speed sensor B34 and the accelerator pedal displacement sensor; and switches the control strategy in real time according to the current working condition;

[0064] Step 6: Shutdown: The gear position of gearbox 2 is restored to neutral.

[0065] The control method of the present invention realizes automatic gear shifting of the transmission 2 according to changes in operating conditions during the process from vehicle starting to vehicle driving.

[0066] like Figure 4 As shown, in order to accurately determine the current working condition, the method in which the main controller determines the working condition according to the signals of the output speed sensor B34 and the accelerator pedal displacement sensor in step 2 and step 5 is:

[0067] First, set the main controller judgment parameters: combine the displacement parameters of the accelerator pedal displacement sensor and the output speed parameters of the output shaft to divide area I into the heavy load area, area II into the transition area, and area III into the light load area;

[0068] Then, the main controller collects data: according to the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft 24 measured by the output speed sensor B34;

[0069] Finally, the main controller determines the operating condition: when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft 24 measured by the output speed sensor B34 are within the range of zone I set by the main controller, the main controller determines it to be a heavy-load condition, and the main transmission clutch C125 and the auxiliary transmission clutch C226 are engaged at the same time; when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft 24 measured by the output speed sensor B34 are within the range of zone II set by the main controller, the main controller determines it to be a transitional condition, and the main transmission clutch C125 and the auxiliary transmission clutch C226 maintain their original states; when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft 24 measured by the output speed sensor B34 are within the range of zone III set by the main controller, the main controller determines it to be a light-load condition, and the main transmission clutch C125 is engaged, and the auxiliary transmission clutch C226 is disengaged.

[0070] In order to achieve power coupling of the auxiliary drive motor, the method for matching the rotation speed of the auxiliary drive motor 12 with the rotation speed of the output shaft 24 in step 4 is as follows:

[0071] Get the transmission ratio i from the main drive motor 11 to the output shaft 24 M1 =Z5 / Z4;

[0072] Get the transmission ratio i from the auxiliary drive motor 12 to the output shaft 24 M2 =(Z2 / Z1)×(Z5 / Z3);

[0073] Wherein, Z1 is the number of teeth of the auxiliary drive shaft gear 221, Z2 is the number of teeth of the intermediate shaft first gear 231, Z3 is the number of teeth of the intermediate shaft second gear 232, Z4 is the number of teeth of the main drive shaft gear 211, and Z5 is the number of teeth of the output shaft gear 241;

[0074] The main drive speed sensor B13 measures the speed of the main drive motor 11 ;

[0075] According to the coupling principle between the main drive motor 11 and the auxiliary drive motor 12,

[0076] ;

[0077] Calculated value of the rotation speed of the auxiliary drive motor 12 ;

[0078] The main controller adjusts the measured speed value of the auxiliary drive motor 12 to the calculated speed value The auxiliary drive speed sensor B25 measures the actual speed value of the auxiliary drive motor 12. When the actual speed value is equal to the calculated speed value, the auxiliary transmission clutch C226 engages.

[0079] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0080] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a walking power system of an electric loader with dual motor inputs, A dual-motor input electric loader travel power system comprises a drive motor (1) and a gearbox (2), wherein the drive motor (1) is connected to an input shaft of the gearbox (2); and is characterized in that: The drive motor (1) comprises a main drive motor (11) and an auxiliary drive motor (12); the gearbox (2) comprises a main drive input shaft (21), an auxiliary drive input shaft (22), an intermediate shaft (23) and an output shaft (24); the main drive motor (11) is connected to the main drive input shaft (21); the auxiliary drive motor (12) is connected to the auxiliary drive input shaft (22); the main drive input shaft (21) and the output shaft (24) are connected via a gear transmission pair; the intermediate shaft (23) is located between the auxiliary drive input shaft (22) and the output shaft (24); the intermediate shaft (23) is connected to the auxiliary drive input shaft (22) and the output shaft (24) via a gear transmission pair; The main drive input shaft (21) is provided with a main drive shaft gear (211), the output shaft (24) is fixedly mounted with an output shaft gear (241), the auxiliary drive input shaft (22) is provided with an auxiliary drive shaft gear (221), and the intermediate shaft (23) is provided with a first intermediate shaft gear (231) and a second intermediate shaft gear (232); the output shaft gear (241) is meshed with the main drive shaft gear (211) and the second intermediate shaft gear (232) at the same time, the first intermediate shaft gear (231) and the second intermediate shaft gear (232) are coaxial, and the first intermediate shaft gear (231) is meshed with the auxiliary drive shaft gear (221); a main drive clutch C1 (25) is provided between the main drive shaft gear (211) and the main drive input shaft (21); An auxiliary transmission clutch C2 (26) is provided between the auxiliary drive input shaft (22) and the intermediate shaft (23); The gearbox (2) is provided with a main drive speed sensor B1 (3) for measuring the speed of the main drive motor (11) and an output speed sensor B3 (4) for measuring the speed of the output shaft (24); An auxiliary drive speed sensor B2 (5) for measuring the speed of the auxiliary drive motor (12) is provided in the gearbox (2); It also includes a main controller, a gear selector and an accelerator pedal displacement sensor, wherein the gear selector sends a control signal to the main controller, and the signals of the main drive speed sensor B1 (3), the output speed sensor B3 (4), the auxiliary drive speed sensor B2 (5) and the accelerator pedal displacement sensor are simultaneously transmitted to the main controller; the main controller controls the main drive clutch C1 (25) and the auxiliary drive clutch C2 (26) of the gearbox (2) as well as the main drive motor (11) and the auxiliary drive motor (12); The control method comprises the following steps: Step 1: Initial state: the gear position of the gearbox (2) is in neutral, and the main transmission clutch C1 (25) and the auxiliary transmission clutch C2 (26) are simultaneously disengaged; Step 2: The gear selector sends a control command to start the main drive motor (11), and the main controller determines the current working condition based on the signals of the accelerator pedal displacement sensor and the output speed sensor B3 (4); when the working condition is light load, the process proceeds to step 3; when the working condition is heavy load, the process proceeds to step 4; Step 3, light load control strategy: the main drive clutch C1 (25) is engaged, and the auxiliary drive clutch C2 (26) is disengaged at the same time, and the power output by the main drive motor (11) is transmitted to the output shaft (24) through the main drive input shaft (21), the main drive clutch C1 (25), the main drive shaft gear (211) and the output shaft gear (241) in sequence; Step 4, heavy load control strategy: the main transmission clutch C1 (25) is first engaged, and the power output by the main drive motor (11) is transmitted to the output shaft gear (241) through the main drive input shaft (21), the main transmission clutch C1 (25) and the main drive shaft gear (211) in sequence; after the main controller adjusts the speed of the auxiliary drive motor (12) to match the speed of the output shaft (24), the auxiliary transmission clutch C2 (26) is engaged, and the power output by the auxiliary drive motor (12) is transmitted to the output shaft gear (241) through the auxiliary drive input shaft (22), the auxiliary drive shaft gear (221), the intermediate shaft first gear (231), the intermediate shaft (23) and the intermediate shaft second gear (232) in sequence, and the converged power is output by the output shaft (24); Step 5: Automatic gear shifting: The main controller determines the change of the working condition based on the signals of the output speed sensor B3 (4) and the accelerator pedal displacement sensor; and switches the control strategy in real time according to the current working condition; Step 6: Stop: The gear position of the gearbox (2) is restored to the neutral state.

2. The control method of the electric loader travel power system with dual motor input according to claim 1, characterized in that: In step 2 and step 5, the method by which the main controller determines the working condition based on the signals of the output speed sensor B3 (4) and the accelerator pedal displacement sensor is: First, set the main controller judgment parameters: combine the displacement parameters of the accelerator pedal displacement sensor and the output speed parameters of the output shaft to divide area I into the heavy load area, area II into the transition area, and area III into the light load area; Then, the main controller collects data: based on the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft (24) measured by the output speed sensor B3 (4); Finally, the main controller determines the working condition: when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft (24) measured by the output speed sensor B3 (4) are within the range of zone I set by the main controller, the main controller determines that it is a heavy load working condition, and the main transmission clutch C1 (25) and the auxiliary transmission clutch C2 (26) are engaged at the same time; when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft (24) measured by the output speed sensor B3 (4) are within the range of zone II set by the main controller, the main controller determines that it is a transition working condition, and the main transmission clutch C1 (25) and the auxiliary transmission clutch C2 (26) maintain their original states; when the displacement parameter of the accelerator pedal displacement sensor and the output speed value of the output shaft (24) measured by the output speed sensor B3 (4) are within the range of zone III set by the main controller, the main controller determines that it is a light load working condition, and the main transmission clutch C1 (25) is engaged, and the auxiliary transmission clutch C2 (26) is disengaged at the same time.

3. The control method of the electric loader travel power system with dual motor input according to claim 1, characterized in that: In step 4, the method for adjusting the rotation speed of the auxiliary drive motor (12) to match the rotation speed of the output shaft (24) is as follows: Obtain the transmission ratio i from the main drive motor (11) to the output shaft (24) M1 =Z5 / Z4; Obtain the transmission ratio i from the auxiliary drive motor (12) to the output shaft (24) M2 =(Z2 / Z1)×(Z5 / Z3); Wherein, Z1 is the number of teeth of the auxiliary drive shaft gear (221), Z2 is the number of teeth of the intermediate shaft first gear (231), Z3 is the number of teeth of the intermediate shaft second gear (232), Z4 is the number of teeth of the main drive shaft gear (211), and Z5 is the number of teeth of the output shaft gear (241); The main drive speed sensor B1 (3) measures the speed of the main drive motor (11). ; According to the coupling principle between the main drive motor (11) and the auxiliary drive motor (12), ； Calculated value of the speed of the auxiliary drive motor (12) ; The main controller adjusts the measured speed value of the auxiliary drive motor (12) to the calculated speed value. The auxiliary drive speed sensor B2 (5) measures the speed value of the auxiliary drive motor (12). When the speed value is equal to the speed calculation value, the auxiliary drive clutch C2 (26) is engaged.

4. The control method of the electric loader travel power system with dual motor input according to claim 1, characterized in that: The auxiliary drive shaft gear (221) is fixedly connected to the auxiliary drive input shaft (22); the intermediate shaft second gear (232) is fixedly mounted on the intermediate shaft (23); and an auxiliary transmission clutch C2 (26) is provided between the intermediate shaft first gear (231) and the intermediate shaft (23).

5. The control method of the electric loader travel power system with dual motor input according to claim 1, characterized in that: The intermediate shaft first gear (231) and the intermediate shaft second gear (232) are respectively fixedly connected to the intermediate shaft (23), and an auxiliary transmission clutch C2 (26) is provided between the auxiliary drive shaft gear (221) and the auxiliary drive input shaft (22).

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