Mixing truck driven by multiple motors and running on track

Abstract

The utility model discloses a mixer truck driven by multiple motors and running on a track, and belongs to the field of new energy vehicles for track operation. A motor is used for replacing an internal combustion engine to serve as power of a hydraulic system, and the defects of low energy utilization rate and the like of power driving of the hydraulic system are overcome, namely direct motor driving is adopted; the high-efficiency feed function of the variable frequency motor is utilized, so that the equipment is particularly energy-saving when running on a rail; therefore, the use amount of expensive vehicle standby batteries is greatly reduced, the equipment cost is obviously reduced, or the endurance mileage is increased. A plurality of implementation modes are provided, so that different implementation modes can be provided according to actual conditions. And a uniform cooling system is also used, so that the cooling requirements of multiple electric driving systems are economically met.

Description

TECHNICAL FIELD

[0001] The present application relates to a multi-motor driven mixing truck running on a track, and is related to the application of variable frequency motor in walking operation machinery. BACKGROUND

[0002] The technology of new energy vehicles is developing rapidly, and the field of walking operation machinery has also begun to replace internal combustion engines with motors.

[0003] The mixing truck running on the track is a high-efficiency tunnel operation machinery developed in China's infrastructure, which uses internal combustion engine to drive multiple hydraulic pumps to drive multiple hydraulic motors to transmit power to the mixing system and walking system to control the operation. If only the motor is used to replace the internal combustion engine, although it reduces carbon emissions and improves the tunnel operation environment, it still relies on hydraulic system to drive the power to implement the operation, and still has problems such as low energy efficiency, insufficient control precision, and failure to fully utilize the advanced achievements of existing variable frequency motor drive system. Abandoning the defects of hydraulic drive, directly driving the walking system and mixing system with motors needs to solve a series of problems. SUMMARY

[0004] The multi-motor driven mixing truck running on a track designed by the present application has a mixing system and a walking system, characterized in that the mixing system and the walking system of the mixing truck are respectively driven by motors through direct mechanical transmission, without hydraulic pumps driving hydraulic motors in between; and the power of the left and right drive wheels of the walking system is distributed by a common motor through a transmission system.

[0005] In this way, the motor replaces the internal combustion engine, reduces carbon emissions, and improves the working environment, especially in tunnel operation.

[0006] Moreover, the mixing system and the walking system of the above-mentioned mixing truck are respectively driven by motors as prime movers, which is not realized by driving hydraulic motors through hydraulic pumps, but by direct non-hydraulic mechanical transmission.

[0007] In this way, the low efficiency of energy utilization of the hydraulic system transmission is abandoned; the excellent performance of variable frequency motor in high-efficiency power feeding during running deceleration can also be utilized, especially for the mixing truck running on the track, which can recover kinetic energy for charging, which is particularly meaningful; from the above two points, the actual power consumption is greatly reduced, thereby greatly reducing the amount of expensive vehicle backup batteries, significantly reducing equipment costs, or increasing the cruising range; the way of distributing power to the left and right drive wheels of the walking system by a common motor through a transmission system is conducive to utilizing the achievements of the electric drive system of new energy vehicles which are developing rapidly.

[0008] In addition, the variable frequency motor is particularly suitable for walking drive, and has the performance characteristics that in the starting stage, stable and powerful torque is output at low speed, the vehicle is stably and powerfully accelerated, and the vehicle can be continuously accelerated in a wide speed range with safe continuous power without relying on a speed changer, the power capacity of the equipment is fully utilized, the working efficiency of the equipment with the same rated power prime mover is obviously improved, and the walking system driven by the hydraulic drive cannot overcome the advantages.

[0009] The application provides an electrically-driven track mixer, and the electrically-driven assembly where the walking drive motor is located is composed of a drive motor, a reducer driven by the drive motor, and a drive axle.

[0010] In this way, the output torque and speed of the motor output characteristics are conveniently converted into the driving torque and speed required by the actual driving wheels.

[0011] Preferably, when the motor output characteristics are suitable, for example, the torque is large enough and the speed range is not too high, the output torque and speed are matched with the existing reduction ratio of the drive axle, the reducer can be omitted, the electrically-driven assembly where the walking drive motor is located is only composed of the drive motor and the drive axle, and the electrically-driven assembly is simplified and saved.

[0012] Preferably, the drive axle uses a differential to distribute the power output of the two ends. Because there are many drive axle products on the market, a suitable power matching and reliable drive axle can be easily found, or the drive axle can be slightly changed to meet specific needs, so that the professional division of labor is relied on to shorten the development cycle and cost.

[0013] Preferably, the output of the reducer is realized by a through shaft extending to both sides of the reducer, the through shaft is used as a driving shaft, and the two ends of the through shaft are installed with driving wheels walking on the rails, or the driving wheels walking on the rails are driven and installed on the two sides of the vehicle frame through universal joints. This scheme is more simple because the driving wheels walking on the rails essentially do not need a differential to distribute power, and the wheels are directly driven by the output of the reducer; and the universal joint connection scheme is beneficial to the disassembly and maintenance of the reducer.

[0014] Another preferable way is that a pair of wheels fixed on the same shaft are supported on the vehicle frame through bearings and bearing seats; a driving assembly composed of a drive motor and a reducer driven by the drive motor is installed on the vehicle frame or a fixed part (for example, a bearing seat) of the vehicle frame, and drives the pair of wheels from the shaft end or the wheel side of the shaft. (See Figure 3 )

[0015] Thus, the conventional wheel and axle which have been mass-produced can be used, and only the connection of the axle (or wheel) and the driving member is changed, and the inspection, maintenance and repair of the driving member are facilitated.

[0016] The application also discloses a track mixer driven by multiple motors, which is characterized in that a cooling system using cooling liquid as heat transfer medium in the multiple motors or multiple electric driving systems is driven by one motor to drive one cooling liquid pump (or pump set) to draw low-temperature cooling liquid from one or two liquid storage containers, and the low-temperature cooling liquid is delivered to components including the motors and frequency converters through a flow distribution device; the high-temperature cooling liquid is cooled by one or two refrigeration devices and then is delivered back to the liquid storage tank; and one upper controller collects and processes information related to the cooling system and temperature.

[0017] Thus, the original independent cooling systems are unified into one system, the cooling control is unified and coordinated, and the hardware is simplified, thereby saving cost and energy consumption. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 Fig. 1 is a schematic diagram of a driving mode of a driving axle used by a mixer driven by multiple motors and running on a track.

[0019] Figure 2 Fig. 2 is a schematic diagram of a driving mode of a reducer through-shaft output used by a mixer driven by multiple motors and running on a track.

[0020] Figure 3 Fig. 3 is a schematic diagram of a driving mode of a wheel pair assembly axle end used by a mixer driven by multiple motors and running on a track.

[0021] Fig. 4 is a curve of external characteristics of a motor driving a mixing system of a mixer driven by multiple motors. Fig. 4 (a) is a continuous characteristic curve, and Fig. 4 (b) is a peak characteristic curve. DETAILED DESCRIPTION

[0022] One of the embodiments is:

[0023] In order to illustrate the specific embodiments of the application, first refer to Figure 1 Fig. 1 is a schematic diagram of a driving mode of a driving axle used by a mixer driven by multiple motors and running on a track. A driving motor 1 is installed on a reducer 2 and drives the reducer; an output shaft of the reducer is connected with a differential 3.1 of a driving axle 3, delivers power to the differential, and distributes the power to two driving wheels 4 running on a steel track through the differential.

[0024] Thus, the motor replaces the internal combustion engine, reduces carbon emissions, and improves the working environment, especially in tunnel operation. And it is not driven by a hydraulic pump to drive a hydraulic motor, which abandons the low efficiency of energy utilization of the hydraulic system transmission; it also takes advantage of the excellent performance of variable frequency motor in high efficiency power supply during driving deceleration, greatly reducing the actual power consumption, reducing the use of expensive vehicle backup batteries, and significantly reducing equipment costs, or increasing the cruising range.

[0025] In addition, it also takes advantage of the performance characteristics of variable frequency motors that are particularly suitable for walking driving: in the starting stage, at low speed, there is stable and powerful torque output, which makes the vehicle accelerate stably and powerfully, and without relying on a transmission, it can continuously accelerate in a wide speed range with safe continuous power, fully utilizing the power capacity of the equipment, and significantly improving the operating efficiency of the equipment with the same rated power prime mover.

[0026] When the external characteristics of the motor are appropriate, such as the torque is large enough and the speed range is not too high, and the output torque and speed are suitable when matched with the existing reduction ratio of the drive axle, the reducer can be omitted, and the electric drive assembly where the walking drive motor is located is only composed of the drive motor and the drive axle, which is simple and saves.

[0027] Embodiment two:

[0028] See Figure 2 : The driving motor 1 is installed on the reducer 2 and drives the reducer; the output of the reducer is realized by the through shaft 3 extending to both sides of the reducer, and the driving wheels 4 running on the steel rails are installed at both ends of the through shaft. This is a more concise transmission method.

[0029] Embodiment three:

[0030] See Figure 3 : A pair of wheels fixed on the same shaft form a wheel pair and shaft assembly 1, which is supported on the frame 0 through the bearing seat assembly 2 composed of bearings and bearing seats; the driving assembly composed of the driving motor 3 and the reducer 4 driven by it is installed on the bearing seat (the frame or other fixed parts of the frame can also be installed), and drives the pair of wheels from one end of the wheel pair and shaft assembly 1. If the bearings of the axle are designed to be inside the wheels, the reducer installed on the frame can also drive the entire wheel pair by directly driving one side wheel; in this way, the length of the motor and reducer assembly extending outside the track can be reduced at the same track gauge.

[0031] Embodiments two and three are similar to embodiment one: the motor replaces the internal combustion engine, and abandons the low efficiency of energy utilization of the hydraulic system transmission; it also takes advantage of the performance characteristics of variable frequency motors that are particularly suitable for walking driving. But each has its own characteristics; it is also possible to use two sets of walking driving systems on one device to implement the walking of the device; in short, it can be selected according to the actual situation.

[0032] The application scheme provided with the front obstacle distance measuring device can be implemented as follows:

[0033] (1) The distance L of the front obstacle is measured by the laser distance measuring device.

[0034] (2) The driving speed is calculated by the motor speed n sensed by the electric driving system.

[0035] V=60n*i*πd / 1000; (wherein n is in 1 / min, i is the reduction ratio of the driving wheel to the motor, d is the diameter of the driving wheel in meters, and V is in km / h) or: V=n*i*πd; (all units are in kg.m.s)

[0036] (3) The expected deceleration a when entering the power feeding is the deceleration value estimated according to the torque generated when the power feeding is reasonable and the torque output by the motor before the power feeding is superimposed on the actual deceleration; (the unit can be in kg.m.s)

[0037] The reasonable power feeding not only depends on the capacity of the equipment, but also is related to the reasonable preference of the user, so the transition of the additional deceleration torque when the power feeding starts is not excluded.

[0038] (4) The deceleration distance after the power feeding is calculated according to the expected deceleration when the power feeding.

[0039] L0=V 2 / (2a); (the unit is in kg.m.s)

[0040] (5) The warning distance Lj can be determined by L0 (for example, Lj=V*1s+L0), that is, when the obstacle enters the warning distance (if the power feeding deceleration is entered immediately, the stopping distance is only one second), the power feeding deceleration program is automatically entered.

[0041] In this way, the safety of driving can be improved; the power feeding deceleration can be used more, and the braking can be reduced, which is very meaningful for energy saving during driving on the track, thereby increasing the cruising range or reducing the expensive vehicle backup battery.

[0042] The embodiment of the present application for the stirring system is to replace the original hydraulic motor driving with the motor driving system, and the excellent performance of the variable frequency motor is utilized, so that the energy consumption is lower, the working efficiency is higher, and the power configuration is more economical.

[0043] Taking the driving system of a 10 cubic meter stirring drum as an example, the motor characteristics used in the present application are shown in FIG. 4, wherein (a) is the continuous characteristic curve of the stirring motor, and the data is shown in the following table:

[0044]

[0045] The above figure reflects that the continuous power of the motor used is only 70kw, far lower than the rated output power configured by the original hydraulic motor scheme.

[0046] Because the discharge at full load is the application scenario where the stirring power needs to be the largest, the 10 cubic stirring drum usually needs a speed of 14r / m, and the torque capacity is 61000Nm. Therefore, the original hydraulic motor must output a power capacity of:

[0047] 14 / 60s*6.28*61000Nm / 0.95 (reducer efficiency) = 94kw; (the original hydraulic system must be configured according to this)

[0048] And the invention scheme utilizes the unique high peak power and torque of the variable frequency motor. See Figure 4(b), and the data is shown in the table below:

[0049] Peak test data

[0050]

[0051]

[0052] The peak power of the motor in this scheme reaches 150kw; it is sufficient to meet the short-time need of 94kw at full load discharge; and the variable frequency motor has the ability to detect and control the output torque and speed of the motor.

[0053] When the invention scheme executes the discharge instruction, it enters the automatic program: first, with the peak torque 310Nm (or slightly lower than the peak torque), and 4200r / m (which corresponds to the stirring drum 14r / m, so that the speed reduction ratio i of the motor and the stirring drum is 300) as the control target, the stirring drum will soon reach the target speed and start discharging under the stable strong torque drive. After the electric drive system senses that the target speed is reached, the program automatically changes to only use the target speed as a single control target; and continuously detects the load torque, as the discharge, the load torque continuously decreases, when the measured load torque and the speed of the product corresponding to the output power reaches the continuous power of the electric drive system, the control mode of the target speed as a single control target is changed to the control mode of the continuous power value of the electric drive system as the control target: that is, continuously increase the speed to adapt to the decrease of the load torque, so as to keep working at the continuous power to achieve higher working efficiency. Of course, the increase of the speed is limited by the allowable range of the system components.

[0054] In addition, when a reducer with a higher cost performance (such as a speed ratio of 130) is needed, the reducer can be driven by the electric drive system, and the speed reduction ratio of the electric drive system to the motor is 300 / 130 = 2.31.

[0055] It should be noted that the engine driving the original stirring hydraulic system has a power of 94kw / (0.88*0.88)=121.5kw (the original internal combustion engine must be guaranteed). Obviously, the energy consumption of the engine original power of 121.5kw and the efficiency advantage of the motor far superior to the internal combustion engine are very significant.

[0056] For example, the variable track mixer truck driven by multiple motors can be implemented by using a combined cooling system as follows:

[0057] The stirring system of the present application adopts a set of electric drive system, the walking system adopts multiple sets of electric drive system, and the auxiliary system (including oil cylinder, air conditioner drive, etc.) adopts a set of electric drive system, thus being a variable track mixer truck driven by multiple motors. The main electric drive systems all select motors with water jacket cooling and controllers with cooling requirements, and the cooling systems with cooling liquid as the heat transfer medium are combined into one cooling system, in which one motor drives one cooling liquid pump, low-temperature cooling liquid is extracted from one storage container, and is delivered to components with heat sources such as motors through a shunt device; high-temperature cooling liquid is returned to the storage tank after being cooled by a refrigeration device; and an upper controller collects and processes information related to the cooling system and temperature. This undoubtedly simplifies the hardware, saves costs and energy consumption, and makes the control of the equipment unified and coordinated.

[0058] Since the target temperature of the cooling control of the permanent magnet synchronous motor is relatively low (for example, 60°), and the target temperature of the cooling control of the controller is relatively high (for example, 95°), when the motor and the controller are separate components, the cooling system can be divided into two sub-systems with different target temperatures of control; one motor drives a series of pump groups, which include two cooling liquid pumps extracting low-temperature cooling liquid with different temperatures from two storage containers, and delivering the low-temperature cooling liquid to components with heat sources such as motors or amplifiers through respective shunt devices; two high-temperature cooling liquids are returned to different storage tanks after being cooled by two refrigeration devices (for example, a compressor gas-liquid phase change cooling device from the motor and a water tank fan heat dissipation device from the amplifier); and an upper controller collects and processes information related to the cooling system and temperature. Using two sub-systems with different target temperatures of control can reduce the load of the compressor gas-liquid phase change cooling device, save refrigeration energy, and ensure the reliable realization of the target temperature control of the motor.

[0059] The foregoing description of preferred embodiments allows any person skilled in the art to use or exploit the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles described herein can be applied to other embodiments without using creativity. Therefore, the present application will not be limited to the embodiments shown herein, but should be based on the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-motor driven track traveling mixer having a mixing system and a traveling system, characterized in that, The stirring system and the walking system of the stirring truck are directly mechanically driven by the motor without the intervention of hydraulic pump and hydraulic motor.

2. The multi-motor driven track-travelling mixer truck according to claim 1, characterized in that, The electric drive assembly where the walking drive motor is located is composed of the drive motor, the speed reducer driven by the drive motor, and the drive axle.

3. The multi-motor driven track-travelling mixer truck according to claim 1, wherein The electric drive assembly where the walking drive motor is located is composed of the drive motor and the drive axle driven by the drive motor.

4. The multi-motor driven track-travelling mixer according to claim 2 or 3, characterized in that, The drive axle uses the differential to distribute the power output of the two ends.

5. The multi-motor driven track-travelling mixer truck according to claim 2, wherein The output of the speed reducer is realized by the through shaft extending to both sides of the speed reducer.

6. The multi-motor driven track-travelling mixer truck according to claim 1, wherein A pair of wheels fixed on the same shaft are supported on the frame by bearings and bearing seats.

7. The multi-motor driven track-travelling mixer truck according to claim 1, wherein The cooling system using the cooling liquid as the heat transfer medium in the multiple motors or multiple electric drive systems is composed of one motor driving one cooling liquid pump or pump group, one or two liquid storage containers, a shunt device, one or two refrigeration devices, and one upper controller. The stirring system and the walking system of the stirring truck are directly mechanically driven by the motor without the intervention of hydraulic pump and hydraulic motor. The electric drive assembly where the walking drive motor is located is composed of the drive motor, the speed reducer driven by the drive motor, and the drive axle. The electric drive assembly where the walking drive motor is located is composed of the drive motor and the drive axle driven by the drive motor. The drive axle uses the differential to distribute the power output of the two ends. The output of the speed reducer is realized by the through shaft extending to both sides of the speed reducer. A pair of wheels fixed on the same shaft are supported on the frame by bearings and bearing seats. The cooling system using the cooling liquid as the heat transfer medium in the multiple motors or multiple electric drive systems is composed of one motor driving one cooling liquid pump or pump group, one or two liquid storage containers, a shunt device, one or two refrigeration devices, and one upper controller.

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