Integrated upper load electric drive assembly and working method thereof

Abstract

This invention relates to an integrated superstructure load electric drive assembly and its operating method, comprising a housing, a first motor, a second motor, a first planetary gear set, a second planetary gear set, and a superstructure load. The first planetary gear set and the first motor are driven together, and the second planetary gear set and the second motor are driven together. The first and second planetary gear sets are driven together via a first transmission path and also via a second transmission path for a disengageable transmission connection. A transmission element on the second planetary gear set, which is driven to the first planetary gear set via the second transmission path, is also disengageably connected to the housing. The first planetary gear set is also driven to the superstructure load via a gear mechanism, and the second planetary gear set is driven to a power output shaft via another gear mechanism to drive the vehicle. This integration of two systems allows for flexible power distribution to the two loads as needed, reducing the power requirements of the two motors, lowering costs, reducing space requirements, facilitating vehicle layout, and saving time and effort.

Description

Technical Field

[0001] This invention relates to the field of mechanical transmission technology, and in particular to an integrated superstructure load electric drive assembly and its working method. Background Technology

[0002] In traditional electric drive technologies for construction machinery such as loaders and heavy-duty forklifts, the travel drive and superstructure load drive are mostly two independent systems. This is not only costly and space-consuming, but also requires maintaining a certain speed and torque to respond promptly to braking and operational demands, even when the superstructure load does not need external power. This results in power consumption, and the independent operation of the two systems makes it impossible to balance their efficiency, leading to low overall system efficiency. To address space constraints, some solutions integrate the two systems into a single housing, but these still do not solve the cost and efficiency problems. A small number of loaders use parallel shaft gear technology to provide power to two loads with a single power source. This technology primarily uses clutch switching to power both loads, but it suffers from slow response and insufficient power to the superstructure load at slower travel speeds. Therefore, the market urgently needs a highly efficient electric drive technology for loaders that can significantly reduce costs and space requirements. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide an integrated superstructure load electric drive assembly and its working method, which organically integrates the walking drive and the superstructure load drive, reduces space occupation, lowers costs, and improves transmission efficiency.

[0004] The present invention is implemented using the following scheme: an integrated superstructure load electric drive assembly, including a housing, a first motor, a second motor, a first planetary gear set, a second planetary gear set, and a superstructure load. The first planetary gear set and the first motor are driven together, and the second planetary gear set and the second motor are driven together. The first planetary gear set and the second planetary gear set are driven together via a first transmission path and also via a second transmission path for a disengageable transmission connection. The transmission element on the second planetary gear set, which is driven together with the first planetary gear set via the second transmission path, is also disengageably connected to the housing. The first planetary gear set is also driven together with the superstructure load via a gear mechanism, and the second planetary gear set is driven together with a power output shaft that outputs power to drive the vehicle via another gear mechanism.

[0005] Furthermore, the first planetary gear set has three different transmission elements that connect to the first transmission path, the second transmission path, and the gear mechanism, respectively, and the second planetary gear set has three different transmission elements that connect to the first transmission path, the second transmission path, and another gear mechanism, respectively.

[0006] Furthermore, the first planetary gear set includes a first sun gear, a first ring gear, a first planet carrier, and first planet gears; the second planetary gear set includes a second sun gear, a second ring gear, a second planet carrier, and second planet gears. The first motor is driven to the first planet carrier, the second motor is driven to the second sun gear, the first planet carrier and the second ring gear are disengaged to form a second transmission path, the second ring gear is disengaged to the housing, and the first sun gear and the second sun gear are driven to form a first transmission path.

[0007] Furthermore, the first planetary carrier and the second gear ring, as well as the second gear ring and the housing, are controlled by the same clutch device. The clutch device includes a first sliding sleeve with engagement teeth. The first sliding sleeve and the second gear ring are slidably connected in the axial direction and drive-connected in the rotational direction. Both the first planetary carrier and the housing are provided with engaged teeth that can engage with the engagement teeth on the first sliding sleeve. When the first sliding sleeve is on one side, the first planetary carrier and the second gear ring are drive-connected through the first sliding sleeve. When the first sliding sleeve is in the middle position, it is in neutral. When the first sliding sleeve is on the other side, the second gear ring is connected to the housing through the first sliding sleeve and is braked by the housing.

[0008] Furthermore, it also includes a first one-way overrunning clutch and a second one-way overrunning clutch. The second gear ring is unidirectionally engaged and disengaged from the housing via the second one-way overrunning clutch. When the second gear ring rotates forward, the second one-way overrunning clutch is disengaged, and the second gear ring can rotate relative to the housing in the forward direction. When the second gear ring rotates in the reverse direction, the second one-way overrunning clutch is locked, and the second gear ring is braked by the housing via the second one-way overrunning clutch. The first planetary carrier is unidirectionally driven to the second gear ring via the first one-way overrunning clutch. The first one-way overrunning clutch is disengaged only when the forward rotation speed of the first planetary carrier is greater than that of the second gear ring, and the first planetary carrier and the second gear ring rotate relative to each other. Otherwise, the first one-way overrunning clutch is locked, and the first planetary carrier and the second gear ring rotate synchronously.

[0009] Furthermore, the second planetary gear set is connected to the power output shaft via a first gear mechanism, which includes a first driving gear and a first driven gear. The first driving gear is connected to the second planetary carrier. The upper load is connected to the first gear ring via a second gear mechanism or a third gear mechanism. The second gear mechanism includes a second driving gear and a second driven gear, and the third gear mechanism includes a third driving gear, an idler gear, and a third driven gear.

[0010] Furthermore, a second sliding sleeve with engaging teeth is provided between the second driven gear and the third driven gear. The second sliding sleeve is slidably connected to the input shaft with the load mounted on it in the axial direction and is driven in the rotational direction. Both the second driven gear and the third driven gear are provided with engaged teeth that can engage with the engaging teeth on the second sliding sleeve. When the second sliding sleeve is in the middle position, it is in neutral. When the second sliding sleeve is on one side, the second driven gear is driven to the input shaft with the load mounted on it through the second sliding sleeve. When the second sliding sleeve is on the other side, the third driven gear is driven to the input shaft with the load mounted on it through the second sliding sleeve.

[0011] Furthermore, it also includes a third one-way overrunning clutch and a fourth one-way overrunning clutch. The second driven gear is unidirectionally connected to the input shaft of the upper load via the third one-way overrunning clutch. When the second driven gear rotates clockwise relative to the input shaft of the upper load, the third one-way overrunning clutch overruns, allowing the second driven gear to rotate clockwise relative to the input shaft of the upper load; otherwise, the third one-way overrunning clutch locks. The third driven gear is unidirectionally connected to the input shaft of the upper load via the fourth one-way overrunning clutch. When the third driven gear rotates clockwise relative to the input shaft of the upper load, the fourth one-way overrunning clutch overruns, allowing the third driven gear to rotate clockwise relative to the input shaft of the upper load; otherwise, the fourth one-way overrunning clutch locks.

[0012] Furthermore, it also includes a get-out clutch, which is located between the first gear ring and the first planetary carrier. The first gear ring is connected to the first planetary carrier in a disengaging transmission via the get-out clutch.

[0013] Another technical solution of the present invention: a method for operating the integrated superstructure load electric drive assembly as described above, comprising the following steps: (1) High torque mode: The first sliding sleeve is located on one side of the housing, the second gear ring is braked by the housing through the first sliding sleeve, and the second driven gear is connected to the input shaft of the upper load through transmission; the first motor and the second motor rotate forward, the power of the first motor is divided into two parts for external output, one part of the power of the first motor drives the upper load through the first planetary carrier, the first planetary gear, the first gear ring, the second driving gear, and the second driven gear, and the torque and speed of the first motor are adjusted according to the power demand of the upper load; the other part of the power of the first motor is transmitted to the second sun gear through the first planetary carrier, the first planetary gear, and the first sun gear; the power of the second motor is transmitted to the power output shaft through the second sun gear and together with the power transmitted to the second sun gear by the first motor through the second planetary gear, the second planetary carrier, and the first gear mechanism, and the torque and speed of the second motor are adjusted according to the driving demand, the second motor rotates forward, and the second planetary carrier rotates forward under the braking of the second gear ring, thereby driving the vehicle forward; (2) High speed mode: The second driven gear is connected to the input shaft of the upper load, the first sliding sleeve is located on one side of the first planetary carrier, the first planetary carrier and the second gear ring are connected through the first sliding sleeve, the first planetary carrier and the second gear ring are synchronized, the power of the first motor is divided into three parts for external output, the first part is output to the upper load, the output path is the same as the high torque mode, the second part is output to the power output shaft through the sun gear, the output path is the same as the high torque mode, and the third part is output to the power output shaft through the first planetary carrier, the second gear ring and the second planetary carrier; (3) Switching from high torque mode to high speed mode: In high torque mode, when the speed of the second motor increases to a certain level and it is difficult to continue to increase or the efficiency of continuing to increase decreases significantly and the vehicle does not need high torque, the first sliding sleeve separates from the housing and is in neutral position. Then the speed of the second motor is reduced. The first motor reduces its speed as much as possible to reduce the speed of the first planetary carrier while meeting the power requirements of the upper load, so as to meet the synchronization of the second gear ring. Under the inertia of the second planetary carrier, the second gear ring rotates from stationary to forward. When the speed of the second gear ring is equal to the speed of the first planetary carrier and tends to exceed the speed of the first planetary carrier, the first one-way overrunning clutch locks up, and the second gear ring and the first planetary carrier synchronize. At this time, the first sliding sleeve moves to the side of the first planetary carrier, so that the first sliding sleeve and the first planetary carrier are smoothly engaged at zero speed difference, so that the assembly switches from high torque mode to high speed mode. (4) Switching from high speed mode to high torque mode: When the speed of the second motor drops to a certain level and continues to drop, the efficiency drops significantly, or when the output torque in high speed mode is difficult to meet the drive requirements, the first sliding sleeve separates from the first planetary carrier and is in neutral position. Then the speed of the second motor is increased, the speed of the second sun gear increases accordingly, and the second gear ring gradually decelerates. When the speed of the second gear ring drops to zero and there is a tendency to reverse, the first one-way overrunning clutch locks. At this time, the first sliding sleeve moves to one side of the housing, so that the first sliding sleeve and the housing are smoothly engaged at zero speed difference, thereby the electric drive assembly switches from high speed mode to high torque mode. (5) Reversing: The first sliding sleeve is located on one side of the housing, the second gear ring is braked by the housing through the first sliding sleeve, and the third driven gear is connected to the input shaft of the upper load. The first motor and the second motor reverse, and the power transmission path of the walking drive is the same as the high torque mode; the power transmission path of the upper load is the same as the high torque mode before it is transmitted to the first gear ring, and then the power of the upper load is transmitted from the first gear ring through the third driving gear, idler gear, and third driven gear to the input shaft of the upper load. The first gear ring reverses, and it still reverses when it is transmitted to the upper load, so as to meet the driving needs of the upper load. (6) Power feeding energy recovery: The torque transmission direction during the power feeding process is opposite to that during the driving process. The first motor and the second motor can be changed from the driving state to the power feeding state to participate in energy recovery. The load on the upper part is preferentially driven by inertia to participate in energy recovery. (7) Getting out of trouble: The first sliding sleeve is on one side of the housing, so that the second gear ring is braked by the housing. The getting-out clutch is engaged, so that the first gear ring and the first planetary carrier are connected by transmission. Thus, the first motor transmits power to the power output shaft through the first planetary carrier, the first planetary gear, the first sun gear, the second sun gear, the second planetary gear, the second planetary carrier, and the first gear mechanism to help the vehicle get out of trouble.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1) Compared with the traditional independently set walking drive assembly and superstructure load drive assembly, this assembly organically integrates the two systems, flexibly allocates the power of the two loads as needed, reduces the power requirements of the two motors, and reduces costs; 2) Since both the dual motors and the superstructure load can recover energy, the energy recovery capability is stronger when braking or coasting power is depleted. Moreover, the energy recovered by the superstructure load does not require secondary conversion, making the overall efficiency very high. This is of particular significance for loaders, which often have high-frequency and large-amplitude braking conditions. 3) In high-speed mode, the first motor and the second motor rotate at the same speed or close to the same speed, so that the speed difference between the first planetary gear set and the second planetary gear set and other rotating parts is zero or close to zero, thereby reducing friction between gears and rotating parts, reducing friction energy loss, reducing wear of parts caused by friction, and further improving transmission efficiency and extending the service life of parts. 4) Compared to traditional AMT transmissions, this assembly can smoothly engage the sliding sleeve at zero speed difference when switching from high torque mode to high speed mode or from high speed mode to high torque mode. It is not only fast, but also free from impact and gear grinding issues. It also avoids the friction plate slippage and wear generated by AT transmissions, and even the excessive slippage that can cause plate burning. Therefore, this assembly has better reliability and a longer service life. 5) The two systems are integrated and share a housing, saving some materials, and share a lubrication and heat dissipation system, thus further reducing costs; 6) The two systems are integrated into one system, which reduces space occupation, facilitates vehicle layout, reduces the number of mounting parts such as brackets used for installation, and the two systems can be installed at one time, saving time and effort; 7) It has a strong ability to get out of trouble. The vehicles carrying loads are often engineering machinery that travel or work on off-road roads with complex road conditions. When the vehicle encounters difficulties such as getting stuck in a pit or being unable to pass a steep slope, the get-out clutch is engaged, which can transmit almost all the torque of the first motor through the first sun gear and the second planetary gear set to the second planetary carrier and help the vehicle get out of trouble through the walking system.

[0015] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through specific embodiments and related drawings. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure of Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the structure of Embodiment 1 of the present invention; The following are the labels in the diagram: 1-First motor, 2-Second motor, 3-Housing, 4-First sliding sleeve, 5-First sun gear, 6-First planetary gear, 7-First ring gear, 8-First planetary carrier, 9-Second sun gear, 10-Second planetary gear, 11-Second ring gear, 12-Second planetary carrier, 13-Second sliding sleeve, 14-First driving gear, 15-First driven gear, 16-Second driving gear, 17-Second driven gear, 18-Third driving gear, 19-Third driven gear, 20-Idler gear, 21-First one-way overrunning clutch, 22-Second one-way overrunning clutch, 23-Third one-way overrunning clutch, 24-Fourth one-way overrunning clutch, 25-Upper load, 26-Input shaft of upper load, 27-Getting-out clutch. Detailed Implementation

[0017] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[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. Example

[0019] like Figure 1As shown, an integrated superstructure load electric drive assembly includes a housing, a first motor, a second motor, a first planetary gear set, a second planetary gear set, and a superstructure load. The first planetary gear set and the first motor are driven together, and the second planetary gear set and the second motor are driven together. The first planetary gear set and the second planetary gear set are driven together via a first transmission path and also via a second transmission path for a clutchable transmission connection. The transmission element on the second planetary gear set, which is driven to the first planetary gear set via the second transmission path, is also clutchably connected to the housing. The first planetary gear set is also driven to the superstructure load via a gear mechanism, and the second planetary gear set is driven to a power output shaft via another gear mechanism to output power to drive the vehicle, thereby realizing a high-torque drive mode and a high-speed drive mode, while meeting the power demand of the superstructure load at any time.

[0020] In this embodiment, the first planetary gear set has three different transmission elements that engage with the first transmission path, the second transmission path, and the gear mechanism, respectively. Similarly, the second planetary gear set has three different transmission elements that engage with the first transmission path, the second transmission path, and another gear mechanism. Specifically, one of the three core transmission elements of the first planetary gear set (i.e., the sun gear, planet carrier, and ring gear) is connected to one of the three core transmission elements of the second planetary gear set. One of the remaining two core transmission elements of the first planetary gear set is also capable of being disengaged and engageably connected to one of the remaining two core transmission elements of the second planetary gear set. The core transmission element on the second planetary gear set that is disengaged and engageably connected to the first planetary gear set is also disengaged and engageably connected to the housing. The remaining one of the three core transmission elements of the first planetary gear set is connected to the superstructure load via a gear mechanism, and the remaining one of the three core transmission elements of the second planetary gear set is connected to the power output shaft via another gear mechanism.

[0021] In this embodiment, the first planetary gear set includes a first sun gear, a first ring gear, a first planet carrier, and first planet gears; the second planetary gear set includes a second sun gear, a second ring gear, a second planet carrier, and second planet gears. A first motor is driven to the first planet carrier, a second motor is driven to the second sun gear, the first planet carrier and the second ring gear are disengaged to form a second transmission path, the second ring gear is disengaged to the housing, and the first sun gear and the second sun gear are driven to form a first transmission path.

[0022] In this embodiment, the first planetary carrier and the second gear ring, as well as the second gear ring and the housing, are controlled by the same clutch device. The clutch device includes a first sliding sleeve with engagement teeth. The first sliding sleeve and the second gear ring are slidably connected in the axial direction and drive-connected in the rotational direction (which may be a spline connection). Both the first planetary carrier and the housing are provided with engaged teeth that can engage with the engagement teeth on the first sliding sleeve. When the first sliding sleeve is on one side, the first planetary carrier and the second gear ring are drive-connected through the first sliding sleeve. When the first sliding sleeve is in the middle position, it is in neutral. When the first sliding sleeve is on the other side, the second gear ring is connected to the housing through the first sliding sleeve and is braked by the housing.

[0023] In practical implementation, the above-mentioned clutch device can also be replaced by two ordinary clutches. That is, the first planetary carrier and the second ring gear are connected by a first clutch for disengagement and engagement, and the second ring gear and the housing are connected by a second clutch for disengagement and engagement. The first clutch is located between the first planetary carrier and the second ring gear to control the on / off state of the first planetary carrier and the second ring gear, and the second clutch is located between the second ring gear and the housing to control the disengagement and engagement of the second ring gear and the housing. When the second clutch is disengaged, the second ring gear can rotate freely, and when the second clutch is engaged, the second ring gear is braked by the housing.

[0024] In this embodiment, a first one-way overrunning clutch and a second one-way overrunning clutch are also included. The second gear ring is unidirectionally engaged and disengaged from the housing via the second one-way overrunning clutch. When the second gear ring rotates forward, the second one-way overrunning clutch is disengaged, and the second gear ring can rotate relative to the housing in the forward direction. When the second gear ring rotates in the reverse direction, the second one-way overrunning clutch is locked, and the second gear ring is braked by the housing via the second one-way overrunning clutch. The first planetary carrier is unidirectionally driven to the second gear ring via the first one-way overrunning clutch. The first one-way overrunning clutch is disengaged only when the forward rotation speed of the first planetary carrier is greater than that of the second gear ring, and the first planetary carrier and the second gear ring rotate relative to each other. Otherwise, the first one-way overrunning clutch is locked, and the first planetary carrier and the second gear ring rotate synchronously.

[0025] In this embodiment, the second planetary gear set is connected to the power output shaft via a first gear mechanism. The driving power is transmitted from the second planetary carrier to drive the vehicle forward via the first gear mechanism. The first gear mechanism includes a first driving gear and a first driven gear, and the first driving gear is connected to the second planetary carrier. The superstructure load is connected to the first gear ring via a second gear mechanism or a third gear mechanism. The second gear mechanism includes a second driving gear and a second driven gear, and the third gear mechanism includes a third driving gear, an idler gear, and a third driven gear.

[0026] In this embodiment, a second sliding sleeve with engaging teeth is provided between the second driven gear and the third driven gear. The second sliding sleeve is slidably connected to the input shaft with the load mounted on it in the axial direction and is driven in the rotational direction (it can be a spline connection). Both the second driven gear and the third driven gear are provided with engaged teeth that can cooperate with the engaging teeth on the second sliding sleeve. When the second sliding sleeve is in the middle position, it is in neutral. When the second sliding sleeve is on one side, the second driven gear is driven to the input shaft with the load mounted on it through the second sliding sleeve. When the second sliding sleeve is on the other side, the third driven gear is driven to the input shaft with the load mounted on it through the second sliding sleeve.

[0027] In this embodiment, a traction clutch is also included. The traction clutch is located between the first gear ring and the first planetary carrier. The first gear ring is disengaged and connected to the first planetary carrier via the traction clutch. Since the traction clutch engages at or near zero vehicle speed, traditional clutches such as engagement sleeves, shift sleeves, bushings with internal and external splines, and dog-tooth clutches are generally suitable for the traction clutch. When the vehicle encounters difficulties such as being stuck in a pit or unable to pass a steep slope, and the superstructure load can be temporarily stopped, the traction clutch engages, synchronizing the first gear ring with the first planetary carrier and holding the first sun gear synchronized. Since the superstructure load is suspended, the first motor can transmit almost full torque to the second planetary carrier through the first planetary carrier, first planet gears, first sun gear, second sun gear, and second planet gears to help the vehicle get out of trouble.

[0028] The aforementioned planetary gear set is a single-stage planetary gear set with an NGW (internal-male-external) structure, featuring three core transmission elements: a sun gear, a ring gear, and a planet carrier. It can also be a composite planetary gear set or a variation thereof, but it still possesses three core transmission elements for power transmission: a sun gear, a ring gear, and a planet carrier, which can be connected to other components. Alternatively, it may have two sun gears and one planet carrier (a ringless planetary gear set) as its three core transmission elements.

[0029] Let the speed of the first sun gear be N1s and its torque be T1s, the speed of the first ring gear be N1r and its torque be T1r, and the speed of the first planetary carrier be N1c and its torque be T1c; the speed of the second sun gear be N2s and its torque be T2s, the speed of the second ring gear be N2r and its torque be T2r, and the speed of the second planetary carrier be N2c and its torque be T2c; the characteristic parameter of the first planetary gear set (number of teeth on the first ring gear / number of teeth on the first sun gear) be i1, the characteristic parameter of the second planetary gear set (number of teeth on the second ring gear / / number of teeth on the second sun gear) be i2, the torque of the first motor be T1 and its speed be N1, and the torque of the second motor be T2 and its speed be N2. Neglect oil stirring, friction losses between gears and bearings.

[0030] The working method of the integrated superstructure load electric drive assembly in this embodiment includes the following steps: (1) High torque mode: The first sliding sleeve is located on one side of the housing, and the second sliding sleeve is located on the side of the second gear mechanism. The second gear ring is braked by the housing through the first sliding sleeve. The second driven gear is connected to the input shaft of the upper load through the second sliding sleeve. The first motor and the second motor rotate forward. The power of the first motor is divided into two parts for external output. One part of the power of the first motor drives the upper load through the first planetary carrier, the first planetary gear, the first gear ring, the second driving gear, and the second driven gear. The torque and speed of the first motor are adjusted according to the power demand of the upper load. The forward rotation of the first motor directly drives the first planetary carrier to rotate forward. According to the motion law of the planetary gear, the first gear ring rotates forward. The second driving gear rotates forward accordingly, causing the second driven gear to rotate in reverse and drive the upper load input shaft to rotate in reverse, while the third gear mechanism idles. Another portion of the power from the first motor is transmitted to the second sun gear via the first planetary carrier, first planetary gears, and first sun gear. The power from the second motor, along with the power transmitted from the first motor to the second sun gear, is output to the power output shaft via the second planetary gears, second planetary carrier, and first gear mechanism. The torque and speed of the second motor are adjusted according to driving requirements. The second motor rotates forward, and under the braking condition of the second ring gear, the second planetary carrier rotates forward, thus driving the vehicle forward. In high torque mode, the torque relationship of each mechanism is as follows: T1c = T1; T1r = T1c*i1 / (i1+1); T1s = T1c / (i1+1); T2s = T2 + T1s; T2c = i2 * (T2 + T1s); T2c = i2 * (T2 + T1 / (i1 + 1)); Therefore, when the torque demand of the upper load on the first gear ring is T1r, the output torque of the first motor is: T1 = T1r * (i1 + 1) / i1; Therefore, when the torque required by the walking drive for the second planetary carrier is T2c, the output torque of the second motor is: T2 = T2c / (i2+1) - T1r / i1; According to the formula T2=T2c / (i2+1)- T1r / i1, when the load on the superstructure is large, the first motor can contribute more torque to the travel drive, reducing the requirement for the output torque of the second motor. The high torque requirement of the superstructure load often occurs during the loading stage, at which time the drive torque requirement is also high. Therefore, the contribution of the first motor to the travel drive torque helps to reduce the second motor from working in the low-speed, high-torque range, thereby improving the working efficiency of the second motor and reducing the overheating phenomenon caused by excessive output torque of the second motor.

[0031] (2) High speed mode: The second sliding sleeve is located on one side of the second gear mechanism. The second driven gear is connected to the input shaft of the upper load through the second sliding sleeve. The first sliding sleeve is located on one side of the first planetary carrier. The first planetary carrier and the second gear ring are connected through the first sliding sleeve. The first planetary carrier and the second gear ring are synchronized. The power of the first motor is divided into three parts for external output. The first part is output to the upper load, and the output path is the same as the high torque mode. The second part is output to the power output shaft through the sun gear, and the output path is the same as the high torque mode. The third part is output to the power output shaft through the first planetary carrier, the second gear ring, and the second planetary carrier. Since the first sun gear and the second sun gear are already connected by a transmission, meaning they are synchronized, if the first planetary carrier is synchronized with the first sun gear (i.e., the first motor and the second motor rotate at the same speed), then the second sun gear and the second ring gear will also be synchronized, holding the second planetary carrier in place. This results in no relative rotation between the first and second planetary gear sets, as well as the rotating components such as gears and bearings, leading to no wear, no heat generation, extended service life, reduced losses, and improved efficiency. Therefore, in high-speed mode, while meeting the requirements for both walking drive and superstructure load drive, the speeds of the first motor and the second motor should be kept as close as possible. Optionally, the second motor and the first motor can rotate at different speeds, with the first motor's speed meeting the speed requirements of the superstructure load.

[0032] In high-speed mode, the speed relationship of each mechanism is as follows: N1c=N1; N1s=N2; N1r = ((i1+1)*N1-N2) / i1; N2s=N2; N2r=N1; N2c = (i2 * N1 + N2) / (i2 + 1); (3) Switching from high torque mode to high speed mode: In high torque mode, when the speed of the second motor increases to a certain level and it is difficult to continue to increase or the efficiency of continuing to increase decreases significantly and the vehicle does not need high torque, the first sliding sleeve separates from the housing and is in neutral position. Then the speed of the second motor is reduced. The first motor reduces its speed as much as possible to reduce the speed of the first planetary carrier while meeting the power requirements of the upper load, so as to meet the synchronization of the second gear ring. Under the inertia of the second planetary carrier, the second gear ring turns from stationary to forward rotation. When the speed of the second gear ring is equal to the speed of the first planetary carrier and tends to exceed the speed of the first planetary carrier, the first one-way overrunning clutch locks up, and the second gear ring and the first planetary carrier synchronize. At this time, the first sliding sleeve moves to the side of the first planetary carrier, so that the first sliding sleeve and the first planetary carrier engage smoothly at zero speed difference, so that the assembly switches from high torque mode to high speed mode. When switching from high torque mode to high speed mode, it is generally in non-working conditions, so the speed of the first planetary carrier can be reduced to a lower level, and the synchronization time between the second gear ring and the first planetary carrier is shorter. (4) Switching from high speed mode to high torque mode: When the speed of the second motor drops to a certain level and continues to drop, the efficiency drops significantly, or when the output torque in high speed mode is difficult to meet the drive requirements, the first sliding sleeve separates from the first planetary carrier and is in neutral position. Then the speed of the second motor is increased, the speed of the second sun gear increases accordingly, and the second gear ring gradually decelerates. When the speed of the second gear ring drops to zero and there is a tendency to reverse, the first one-way overrunning clutch locks. At this time, the first sliding sleeve moves to one side of the housing, so that the first sliding sleeve and the housing are smoothly engaged at zero speed difference, thereby the electric drive assembly switches from high speed mode to high torque mode. (5) Reversing: The first sliding sleeve is on one side of the housing, the second gear ring is braked by the housing through the first sliding sleeve, the second sliding sleeve is on one side of the third gear mechanism, and the third driven gear is connected to the input shaft of the upper load through the second sliding sleeve. The first motor and the second motor reverse, and the power transmission path of the walking drive is the same as the high torque mode, but the rotation direction of each transmission component on the transmission path is opposite; the power transmission path of the upper load is the same as the high torque mode before it is transmitted to the first gear ring, but the rotation direction of each transmission component on the transmission path is opposite, and then the power of the upper load is transmitted from the first gear ring through the third driving gear, idler gear, and third driven gear to the input shaft of the upper load. The first gear ring reverses, and it still reverses when it is transmitted to the upper load, which meets the driving needs of the upper load. The second gear mechanism idles. In the reversing state, the torque and speed relationship of each mechanism of the two motors and the two planetary gear sets is the same as the high torque mode, but the force direction and direction are opposite; (6) Power recovery: The torque transmission direction during the power recovery process is opposite to that during the driving process. That is, the power is transmitted from the wheels to the assembly through the corresponding transmission mechanism. The first motor and the second motor can switch from driving state to power recovery state to participate in energy recovery. The superstructure load is driven by inertia and thus participates in energy recovery. During large-amplitude braking power recovery, the first motor, the second motor and the superstructure load all participate in energy recovery. During medium-amplitude or coasting power recovery, the superstructure load and the first motor recover energy first. The power recovery process always ensures the torque and speed requirements of the superstructure load. When the recovered energy cannot meet the requirements of the superstructure load, the first motor stops power recovery and switches to driving to ensure the power required by the superstructure load. The assembly has three devices that can participate in energy recovery, making the recovery method more flexible and recovering more energy. Moreover, the superstructure load does not need secondary conversion to recover energy, which is conducive to greatly improving efficiency, reducing the wear of brake parts and increasing service life.

[0033] (7) Getting out of trouble: When the vehicle encounters difficulties such as getting stuck in a pit or being unable to pass through a steep slope and the load on the superstructure can be temporarily stopped, the first sliding sleeve is on one side of the housing, so that the second gear ring is braked by the housing, the getting-out clutch is engaged, and the first gear ring and the first planetary carrier are connected by transmission, so that the first motor can transmit power to the power output shaft at almost full torque through the first planetary carrier, the first planetary gear, the first sun gear, the second sun gear, the second planetary gear, the second planetary carrier, and the first gear mechanism to help the vehicle get out of trouble. The output torque of the second planetary carrier is T2c=i2*(T1+T2).

[0034] The advantages of this invention integrating the superstructure load electric drive assembly are as follows: 1) Compared with the traditional independently set walking drive assembly and superstructure load drive assembly, this assembly organically integrates the two systems, flexibly allocates the power of the two loads as needed, reduces the power requirements of the two motors, and reduces costs; 2) Since both the dual motors and the superstructure load can recover energy, the energy recovery capability is stronger when braking or coasting power is depleted. Moreover, the energy recovered by the superstructure load does not require secondary conversion, making the overall efficiency very high. This is of particular significance for loaders, which often have high-frequency and large-amplitude braking conditions. 3) In high-speed mode, the first motor and the second motor rotate at the same speed or close to the same speed, so that the speed difference between the first planetary gear set and the second planetary gear set and other rotating parts is zero or close to zero, thereby reducing friction between gears and rotating parts, reducing friction energy loss, reducing wear of parts caused by friction, and further improving transmission efficiency and extending the service life of parts. 4) Compared to traditional AMT transmissions, this assembly can smoothly engage the sliding sleeve at zero speed difference when switching from high torque mode to high speed mode or from high speed mode to high torque mode. It is not only fast, but also free from impact and gear grinding issues. It also avoids the friction plate slippage and wear generated by AT transmissions, and even the excessive slippage that can cause plate burning. Therefore, this assembly has better reliability and a longer service life. 5) The two systems are integrated and share a housing, saving some materials, and share a lubrication and heat dissipation system, thus further reducing costs; 6) The two systems are integrated into one system, which reduces space occupation, facilitates vehicle layout, reduces the number of mounting parts such as brackets used for installation, and the two systems can be installed at one time, saving time and effort; 7) It has a strong ability to get out of trouble. The vehicles carrying loads are often engineering machinery that travel or work on off-road roads with complex road conditions. When the vehicle encounters difficulties such as getting stuck in a pit or being unable to pass a steep slope, the get-out clutch is engaged, which can transmit almost all the torque of the first motor through the first sun gear and the second planetary gear set to the second planetary carrier and help the vehicle get out of trouble through the walking system.

[0035] Example 2: In this example, the second sliding sleeve structure in Example 1 is replaced with two one-way overrunning clutches, such as... Figure 2 As shown.

[0036] In this embodiment, a third one-way overrunning clutch and a fourth one-way overrunning clutch are also included. The second driven gear is unidirectionally connected to the input shaft of the upper load via the third one-way overrunning clutch. When the second driven gear rotates clockwise relative to the input shaft of the upper load, the third one-way overrunning clutch overruns, allowing the second driven gear to rotate clockwise relative to the input shaft of the upper load. Otherwise, the third one-way overrunning clutch locks, and power can be transmitted from the second driven gear to the input shaft of the upper load. The third driven gear is unidirectionally connected to the input shaft of the upper load via the fourth one-way overrunning clutch. When the third driven gear rotates clockwise relative to the input shaft of the upper load, the fourth one-way overrunning clutch overruns, allowing the third driven gear to rotate clockwise relative to the input shaft of the upper load. Otherwise, the fourth one-way overrunning clutch locks, and power can be transmitted from the third driven gear to the input shaft of the upper load. Due to the presence of the idler gear, the second and third driven gears always rotate in opposite directions. Therefore, power can only be transmitted to the input shaft of the upper load via one of the second and third gear mechanisms, causing the input shaft of the upper load to always rotate in reverse, thus meeting the needs of driving the upper load.

[0037] The working method of the integrated superstructure load electric drive assembly in this embodiment is basically the same as that in Embodiment 1, except that the control operation of the second sliding sleeve is changed to be controlled by the third one-way overrunning clutch and the fourth one-way overrunning clutch.

[0038] Example 3: This example does not include the third gear mechanism, second sliding sleeve, third one-way overrunning clutch, and fourth one-way overrunning clutch found in Example 1. The second driven gear is directly connected to the input shaft of the upper load, as shown below. Figure 3 As shown.

[0039] The working method of the integrated superstructure load electric drive assembly in this embodiment includes the following steps: (1) High torque mode: Without the second sliding sleeve and the third gear mechanism, the second driven gear is connected to the upper load input shaft, and the power is transmitted from the first gear ring through the second driving gear and the second driven gear to the upper load input shaft to provide power for the upper load; the rest is the same as the high torque mode of embodiment 1. 2) High-speed mode: Without the second sliding sleeve and the third gear mechanism, the second driven gear is connected to the upper load input shaft. Power is transmitted from the first gear ring through the second driving gear and the second driven gear to the upper load input shaft to provide power for the upper load; the rest is the same as the high-speed mode of embodiment 1. 3) Switching from high torque mode to high speed mode: Same as switching from high torque mode to high speed mode in Example 1; 4) Switching from high-speed mode to high-torque mode: Same as switching from high-speed mode to high-torque mode in Example 1; 5) Reversing: The first sliding sleeve is located on one side of the housing, and the second gear ring is braked by the housing through the first sliding sleeve. The second motor reverses, and the power transmission path for driving is the same as in the high torque mode, but the rotation directions of each transmission component in the transmission path are opposite. The reversing of the second motor drives the first sun gear to reverse through the second sun gear. The reversing first sun gear exerts a positive force on the first gear ring through the first planetary gear. When reversing, the speed of the second motor is often low, so the speed of the first sun gear is also low. The forward rotation of the first motor compensates for the insufficient speed of the first sun gear. Under the combined action of the first sun gear and the first motor, the first gear ring rotates forward, driving the upper load to work in reverse through the second gear mechanism. When the speed of the second motor is high, and the load torque and speed requirements are both low, the first motor can be switched to forward rotation to feed the motor or reverse low speed to feed the power, so as to improve energy utilization.

[0040] Unless otherwise stated, if any of the technical solutions disclosed in this invention specify a numerical range, then the disclosed numerical range is a preferred numerical range. Anyone skilled in the art should understand that the preferred numerical range is merely one among many feasible numerical values ​​that has a more obvious or representative technical effect. Because there are many numerical values, it is impossible to list them all. Therefore, this invention discloses only some numerical values ​​to illustrate the technical solutions of this invention. Furthermore, the numerical values ​​listed above should not constitute a limitation on the scope of protection of this invention.

[0041] If this invention discloses or relates to mutually fixedly connected components or structural parts, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured in one piece using a casting process) (except where it is obviously impossible to use an integral molding process).

[0042] In addition, unless otherwise stated, the terms used in any of the technical solutions disclosed in this invention to indicate positional relationships or shapes include states or shapes that are similar to, close to, or approximate with those states or shapes.

[0043] Any component provided by this invention can be assembled from multiple individual components or can be a single component manufactured by a one-piece molding process.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An integrated superstructure load electric drive assembly, characterized in that: The device includes a housing, a first motor, a second motor, a first planetary gear set, a second planetary gear set, and a superstructure load. The first planetary gear set and the first motor are driven together, and the second planetary gear set and the second motor are driven together. The first planetary gear set and the second planetary gear set are driven together via a first transmission path and also via a second transmission path for a disengageable transmission connection. The transmission element on the second planetary gear set, which is driven together with the first planetary gear set via the second transmission path, is also disengageable from the housing. The first planetary gear set is also driven together with the superstructure load via a gear mechanism, and the second planetary gear set is driven together with a power output shaft that outputs power to drive the vehicle via another gear mechanism.

2. The integrated superstructure load electric drive assembly according to claim 1, characterized in that: The first planetary gear set has three different transmission elements that connect to the first transmission path, the second transmission path, and the gear mechanism, respectively. The second planetary gear set has three different transmission elements that connect to the first transmission path, the second transmission path, and another gear mechanism, respectively.

3. The integrated superstructure load electric drive assembly according to claim 2, characterized in that: The first planetary gear set includes a first sun gear, a first ring gear, a first planet carrier, and first planet gears; the second planetary gear set includes a second sun gear, a second ring gear, a second planet carrier, and second planet gears. A first motor is driven to the first planet carrier, a second motor is driven to the second sun gear, the first planet carrier and the second ring gear are disengaged to form a second transmission path, the second ring gear is disengaged to the housing, and the first sun gear and the second sun gear are driven to form a first transmission path.

4. The integrated superstructure load electric drive assembly according to claim 3, characterized in that: The first planetary carrier and the second gear ring, as well as the second gear ring and the housing, are controlled by the same clutch device. The clutch device includes a first sliding sleeve with engagement teeth. The first sliding sleeve and the second gear ring are slidably connected in the axial direction and drive-connected in the rotational direction. Both the first planetary carrier and the housing are provided with engaged teeth that can engage with the engagement teeth on the first sliding sleeve. When the first sliding sleeve is on one side, the first planetary carrier and the second gear ring are drive-connected through the first sliding sleeve. When the first sliding sleeve is in the middle position, it is in neutral. When the first sliding sleeve is on the other side, the second gear ring is connected to the housing through the first sliding sleeve and is braked by the housing.

5. The integrated superstructure load electric drive assembly according to claim 4, characterized in that: It also includes a first one-way overrunning clutch and a second one-way overrunning clutch. The second gear ring is unidirectionally engaged and disengaged from the housing via the second one-way overrunning clutch. When the second gear ring rotates forward, the second one-way overrunning clutch is disengaged, and the second gear ring can rotate relative to the housing in the forward direction. When the second gear ring rotates in the reverse direction, the second one-way overrunning clutch is locked, and the second gear ring is braked by the housing via the second one-way overrunning clutch. The first planetary carrier is unidirectionally engaged and disengaged from the second gear ring via the first one-way overrunning clutch. The first one-way overrunning clutch is disengaged only when the forward rotation speed of the first planetary carrier is greater than that of the second gear ring, and the first planetary carrier and the second gear ring rotate relative to each other. Otherwise, the first one-way overrunning clutch is locked, and the first planetary carrier and the second gear ring rotate synchronously.

6. The integrated superstructure load electric drive assembly according to claim 5, characterized in that: The second planetary gear set is driven to the power output shaft through a first gear mechanism. The first gear mechanism includes a first driving gear and a first driven gear. The first driving gear is driven to the second planetary carrier. The upper load is driven to the first gear ring through a second gear mechanism or a third gear mechanism. The second gear mechanism includes a second driving gear and a second driven gear. The third gear mechanism includes a third driving gear, an idler gear, and a third driven gear.

7. The integrated superstructure load electric drive assembly according to claim 6, characterized in that: A second sliding sleeve with engaging teeth is provided between the second driven gear and the third driven gear. The second sliding sleeve is slidably connected to the input shaft with the load mounted on it in the axial direction and is driven in the rotational direction. Both the second driven gear and the third driven gear are provided with engaged teeth that can engage with the engaging teeth on the second sliding sleeve. When the second sliding sleeve is in the middle position, it is in neutral. When the second sliding sleeve is on one side, the second driven gear is driven to the input shaft with the load mounted on it through the second sliding sleeve. When the second sliding sleeve is on the other side, the third driven gear is driven to the input shaft with the load mounted on it through the second sliding sleeve.

8. The integrated superstructure load electric drive assembly according to claim 6, characterized in that: It also includes a third one-way overrunning clutch and a fourth one-way overrunning clutch. The second driven gear is unidirectionally connected to the input shaft of the upper load through the third one-way overrunning clutch. When the second driven gear rotates clockwise relative to the input shaft of the upper load, the third one-way overrunning clutch overruns, and the second driven gear can rotate clockwise relative to the input shaft of the upper load. Otherwise, the third one-way overrunning clutch is locked. The third driven gear is unidirectionally connected to the input shaft of the upper load through the fourth one-way overrunning clutch. When the third driven gear rotates clockwise relative to the input shaft of the upper load, the fourth one-way overrunning clutch overruns, and the third driven gear can rotate clockwise relative to the input shaft of the upper load. Otherwise, the fourth one-way overrunning clutch is locked.

9. The integrated superstructure load electric drive assembly according to claim 6, characterized in that: It also includes a get-out clutch, which is located between the first gear ring and the first planetary carrier. The first gear ring is connected to the first planetary carrier in a clutchable transmission via the get-out clutch.

10. A method for operating the integrated superstructure load electric drive assembly as described in claim 9, characterized in that: Includes the following steps: (1) High torque mode: The first sliding sleeve is located on one side of the housing, the second gear ring is braked by the housing through the first sliding sleeve, and the second driven gear is connected to the input shaft of the upper load through transmission; the first motor and the second motor rotate forward, the power of the first motor is divided into two parts for external output, one part of the power of the first motor drives the upper load through the first planetary carrier, the first planetary gear, the first gear ring, the second driving gear, and the second driven gear, and the torque and speed of the first motor are adjusted according to the power demand of the upper load; the other part of the power of the first motor is transmitted to the second sun gear through the first planetary carrier, the first planetary gear, and the first sun gear; the power of the second motor is transmitted to the power output shaft through the second sun gear and together with the power transmitted to the second sun gear by the first motor through the second planetary gear, the second planetary carrier, and the first gear mechanism, and the torque and speed of the second motor are adjusted according to the driving demand, the second motor rotates forward, and the second planetary carrier rotates forward under the braking of the second gear ring, thereby driving the vehicle forward; (2) High speed mode: The second driven gear is connected to the input shaft of the upper load, the first sliding sleeve is located on one side of the first planetary carrier, the first planetary carrier and the second gear ring are connected through the first sliding sleeve, the first planetary carrier and the second gear ring are synchronized, the power of the first motor is divided into three parts for external output, the first part is output to the upper load, the output path is the same as the high torque mode, the second part is output to the power output shaft through the sun gear, the output path is the same as the high torque mode, and the third part is output to the power output shaft through the first planetary carrier, the second gear ring and the second planetary carrier; (3) Switching from high torque mode to high speed mode: In high torque mode, when the speed of the second motor increases to a certain level and it is difficult to continue to increase or the efficiency of continuing to increase decreases significantly and the vehicle does not need high torque, the first sliding sleeve separates from the housing and is in neutral position. Then the speed of the second motor is reduced. The first motor reduces its speed as much as possible to reduce the speed of the first planetary carrier while meeting the power requirements of the upper load, so as to meet the synchronization of the second gear ring. Under the inertia of the second planetary carrier, the second gear ring rotates from stationary to forward. When the speed of the second gear ring is equal to the speed of the first planetary carrier and tends to exceed the speed of the first planetary carrier, the first one-way overrunning clutch locks up, and the second gear ring and the first planetary carrier synchronize. At this time, the first sliding sleeve moves to the side of the first planetary carrier, so that the first sliding sleeve and the first planetary carrier are smoothly engaged at zero speed difference, so that the assembly switches from high torque mode to high speed mode. (4) Switching from high speed mode to high torque mode: When the speed of the second motor drops to a certain level and continues to drop, the efficiency drops significantly, or when the output torque in high speed mode is difficult to meet the drive requirements, the first sliding sleeve separates from the first planetary carrier and is in neutral position. Then the speed of the second motor is increased, the speed of the second sun gear increases accordingly, and the second gear ring gradually decelerates. When the speed of the second gear ring drops to zero and there is a tendency to reverse, the first one-way overrunning clutch locks. At this time, the first sliding sleeve moves to one side of the housing, so that the first sliding sleeve and the housing are smoothly engaged at zero speed difference, thereby the electric drive assembly switches from high speed mode to high torque mode. (5) Reversing: The first sliding sleeve is located on one side of the housing, the second gear ring is braked by the housing through the first sliding sleeve, and the third driven gear is connected to the input shaft of the upper load. The first motor and the second motor reverse, and the power transmission path of the walking drive is the same as the high torque mode; the power transmission path of the upper load is the same as the high torque mode before it is transmitted to the first gear ring, and then the power of the upper load is transmitted from the first gear ring through the third driving gear, idler gear, and third driven gear to the input shaft of the upper load. The first gear ring reverses, and it still reverses when it is transmitted to the upper load, so as to meet the driving needs of the upper load. (6) Power feeding energy recovery: The torque transmission direction during the power feeding process is opposite to that during the driving process. The first motor and the second motor can be changed from the driving state to the power feeding state to participate in energy recovery. The load on the upper part is preferentially driven by inertia to participate in energy recovery. (7) Getting out of trouble: The first sliding sleeve is on one side of the housing, so that the second gear ring is braked by the housing. The getting-out clutch is engaged, so that the first gear ring and the first planetary carrier are connected by transmission. Thus, the first motor transmits power to the power output shaft through the first planetary carrier, the first planetary gear, the first sun gear, the second sun gear, the second planetary gear, the second planetary carrier, and the first gear mechanism to help the vehicle get out of trouble.

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