WO2022067633A1

WO2022067633A1 - Electric vehicle and electrified power system comprised therein

Info

Publication number: WO2022067633A1
Application number: PCT/CN2020/119274
Authority: WO
Inventors: 杨佳宁; 董婷婷
Original assignee: 罗伯特·博世有限公司; 杨佳宁; 董婷婷
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2022-04-07
Also published as: CN116171235A

Abstract

An electrified power system (3) for an electric vehicle, comprising a traveling unit (31) and a working unit (32). The traveling unit (31) comprises a first electric motor (311) and a power transmission mechanism (312), and the working unit (32) comprises a second electric motor (321), a work drive system (322) and a work device (323). The electrified power system (3) also comprises a power distribution apparatus (33), which is connected to two electric motors (311, 321) respectively and which is used to distribute/combine the power outputted by the two electric motors (311, 321). In a driving mode, the power distribution apparatus (33) is in a first working state so that the output power from the two electric motors (311, 321) is combined and outputted to the power transmission mechanism (312). In a working mode, the power distribution apparatus (33) is in a second working state so that only the output power of the first electric motor (311) is provided to the power transmission mechanism (312), and only the output power of the second electric motor (321) is provided to the work drive system (322). The electrified power system (3) effectively improves the usage efficiency of the electric motors (311, 321), simplifies the system structure, reduces system costs, and saves mounting space.

Description

Electric vehicles and electrified powertrains they include

technical field

The present invention relates to electric vehicles and powertrains including them, and more particularly to an electric vehicle, such as a street sweeper, and electrified powertrains including them.

Background technique

A street sweeper is a municipal vehicle used to clean streets. The power system of the street sweeper includes a driving unit and a working unit. The travel unit is used to propel the vehicle forward and backward by driving the wheels, and the work unit is used to clean the street by means of sweeping equipment including exhaust fans, brushes, etc. Accordingly, street sweepers have two basic modes of operation: a driving mode and a work mode. In the driving mode, the street sweeper drives like other vehicles on the street without cleaning the street, and the work unit is in a non-working state; in the work mode, the street sweeper drives at a low speed and cleans the street, and the work unit is in the working state .

FIG. 1 shows the structural layout of a conventional fuel power system 1 of a street sweeper in the prior art. As shown in FIG. 1 , a conventional fuel power system 1 of a street sweeper in the prior art includes a traveling unit 11 and a working unit 12 . The driving unit 11 includes a chassis engine 111; a clutch 112, one end of which is connected to the power output end of the chassis engine 111; a power transmission mechanism 113 with a speed change function, whose input end is connected to the other end of the clutch 112; a differential 114, which The input end is connected to the output end of the power transmission mechanism 113 ; and the driving wheel 115 is connected to the output end of the differential 114 . The work unit 12 includes an auxiliary engine 121; a clutch 122, one end of which is connected to the power output end of the auxiliary engine 121; a work drive system (hydraulic system) 123, whose input end is connected to the other end of the clutch 122; and a cleaning device 124, which Connected to the output end of the work drive system (hydraulic system) 123, the cleaning equipment 124 includes devices such as an exhaust fan 1241, a brush 1242, etc. These devices are driven by the output power of the work drive system (hydraulic system) 123 to perform street cleaning operations .

In the running mode, the clutches 112 respectively connected to the chassis engine 111 and the power transmission mechanism 113 are in a coupled state, so as to transmit the power output from the chassis engine 111 to the power transmission mechanism 113, and then through the power transmission mechanism 113 (shift processing) and The differential 114 (deceleration and differential processing) connected to the power transmission mechanism 113 transmits the power to the driving wheels 115 so that the driving wheels 115 are driven so that the street sweeper is in a running state. At the same time, in the driving mode, the clutch 122 in the working unit 12 is in a disengaged state, so that the power generated by the auxiliary engine 121 cannot be transmitted to the working drive system (hydraulic system) 123 through the clutch 122, thereby making it compatible with the working drive system (hydraulic system). ) 123 connected to the cleaning device 124 is not driven to work.

In the working mode, the

clutches

112 and 122 are both engaged, so that the power output from the chassis engine 111 is transmitted to the drive wheels 115, so that the street sweeper is in a running state. At the same time, the power output by the auxiliary engine 121 is also transmitted to the cleaning device 124, so that the cleaning device 124 is driven, and the exhaust fan 1241, the brush 1242 and other devices included in the cleaning device 124 are in operation to clean the street.

Electrified powertrains for street sweepers are becoming more and more popular in the market due to the growing demand for environmental protection and energy saving.

FIG. 2 shows the structural layout of the electrified power system 2 of the street sweeper in the prior art. The structural difference between the electrified power system 2 shown in FIG. 2 and the conventional fuel power system 1 shown in FIG. 1 is that: (1) the chassis engine 111 included in the traveling unit 11 in the conventional power system 1 is The first electric motor 211 included in the travel unit 21 is replaced; the auxiliary engine 121 included in the work unit 12 in the conventional power system 1 is replaced by the second electric motor 221 included in the work unit 22 in the electrified power system 2; ( 2) In the electrified power system 2, the

clutches

112 and 122 in the conventional power system 1 are not included, the power output end of the first electric motor 211 is directly connected with the power transmission mechanism 113, and the power output end of the second electric motor 221 A drive system (hydraulic system) 123 is connected.

The working principle of the electrified power system 2 shown in FIG. 2 is basically similar to that of the conventional fuel power system 1 shown in FIG. 1 , and the power requirements of the electric motor are also different when the street sweeper is in different operation modes. FIGS. 3( a ) and ( b ) show the driving mode and the working mode of the electrified powertrain 2 , respectively.

As shown in FIG. 3( a ), in the driving mode, the street sweeper is in a driving state. The electric motor 211 in the travel unit 21 needs to output high power in order to drive the street sweeper, while the electric motor 221 in the work unit 22 does not need to output power.

As shown in FIG. 3( b ), in the work mode, the street sweeper runs at a low speed and the work unit 12 is in the work state to clean the street by the sweeping device 124 . Therefore, the electric motor 211 in the travel unit 21 only needs to provide relatively low power (compared to the output power of the electric motor 211 in the travel mode shown in Fig. 3(a)), while the electric motor 221 in the work unit 22 must provide sufficient power The power of the cleaning equipment 124 is used to make the devices such as the exhaust fan 1241, the brush 1242 and the like included in the cleaning equipment 124 in the working state to clean the street.

It can be seen that in the prior art electrified power system 2 shown in FIG. 2, in the driving mode, the electric motor 221 in the working unit 22 does not need to output power and its working capacity is completely wasted, and in the working mode, The electric motor 211 in the travel unit 21 only needs to output relatively low power so that it cannot work efficiently. In other words, the electrified power system of the prior art cannot effectively use the output power of each electric motor when the street sweeper is in different operation modes, and the structure of the electrified power system 2 shown in FIG. 2 is unreasonable. There is room for obvious optimization and improvement in terms of efficiency of use, simplifying the structure of the electrified power system, and reducing the cost of the electrified power system.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an electric vehicle and an electrified power system included therein, which can effectively improve the use efficiency of the electric motor in the electrified power system, simplify the structure of the electrified power system, reduce the cost of the electrified power system and save the installation space .

According to a first aspect of the present invention, there is provided an electrified power system for an electric vehicle, the electrified power system including a traveling unit for driving the electric vehicle to move forward and backward and a work unit for performing various operations , the driving unit includes a first electric motor; a power transmission mechanism, the input end of which is connected with the power output end of the first electric motor; a differential, whose input end is connected with the output end of the power transmission mechanism; and a drive wheel , which is connected with the output end of the differential for driving the electric vehicle to move forward and backward, the working unit includes a second electric motor; the working drive system, the input end of which is connected to the power output of the second electric motor and the operation equipment, which is connected with the output end of the operation drive system and is used for performing various operations, and is characterized in that:

The electrified power system further includes a power distribution device, which is respectively connected with the first electric motor, the second electric motor and the work drive system, and is used for distributing/combining the output power of the first electric motor and the second electric motor, to provide the power transmission mechanism and/or the work drive system,

Wherein, in the running mode, the power distribution device is in a first working state, so that the output power from the first electric motor and the second electric motor is combined and provided to the power transmission mechanism through the power distribution device, and the first electric motor is provided to the power transmission mechanism. The output power of the two electric motors is not provided to the work drive system.

Wherein, in the working mode, the power distribution device is in a second working state so that only the output power of the first electric motor is provided to the power transmission mechanism, and only the output power of the second electric motor is provided to the work drive system .

In a preferred embodiment, the first electric motor and the second electric motor are arranged coaxially, and the power distribution device is a switching device disposed between the first electric motor and the second electric motor, wherein, during driving mode, the switching device is in the first working state to connect the first electric motor and the second electric motor in series, the output power of the first electric motor and the second electric motor is combined for transmission to the power transmission mechanism, and wherein , in the working mode, the switching device is in the second working state so that only the output power of the first electric motor is supplied to the power transmission mechanism, and only the output power of the second electric motor is supplied to the working drive system.

In a preferred embodiment, the switching device includes a first switch, which is arranged between the first motor and the second motor and is respectively connected to the input end of the first motor and the output end of the second motor. and a second switch arranged between the second electric motor and the work drive system and connected to the output end of the second electric motor and the input end of the work drive system, respectively, wherein, in the travel mode, the switching device In the first operating state, the first switch is closed and the second switch is opened to connect the first motor and the second motor in series, the output power of the first motor and the second motor being combined to transmission to the power transmission mechanism, and wherein, in the operating mode, the switching device is in the second operating state, the first switch is opened and the second switch is closed to enable the output of the first motor only Power is provided to the power transmission mechanism, and only the output power of the second electric motor is provided to the work drive system

In a preferred embodiment, the electrified power system further includes a control unit connected with the power distribution device, wherein, in the driving mode, the control unit makes the power distribution device in the first working state; during operation In the mode, the control unit makes the power distribution device in the second working state.

In a preferred embodiment, the first switch is a clutch, and the second switch is a power take-off switch.

In a preferred embodiment, the electric vehicle is a street sweeper, the working drive system is a hydraulic system, and the working equipment is a sweeping device including devices such as an exhaust fan and a brush.

According to a second aspect of the present invention, there is provided an electric vehicle comprising the above electrified powertrain.

According to the electric vehicle of the present invention and the electrified power system it includes, when the electric vehicle is a street sweeper, the operation drive system is a hydraulic system, and the operation equipment is a cleaning equipment including devices such as an exhaust fan and a brush. In the driving mode, the street sweeper is in the driving state and the power distribution device is in the first working state, so that the first electric motor and the second electric motor are connected in series and the second electric motor is decoupled from the hydraulic system (work drive system), so that the first electric motor and the output power of the second electric motor are combined to transmit to the power transmission mechanism, so that the drive wheels of the street sweeper are driven by the combined output power, so that the street sweeper can be driven at a higher speed (compared to the work mode) Move forward and backward.

In the working mode, the street sweeper runs at a low speed while sweeping the street, and the power distribution device is in the second working state, so that the second electric motor is only coupled to the hydraulic system and decoupled from the first electric motor, so that only the output power of the second electric motor is It is supplied to the sweeping device through the hydraulic system, so that the sweeping device works to sweep the street. Meanwhile, only the output power of the first electric motor is supplied to the driving wheels through the power transmission mechanism, thereby driving the street sweeper to move forward and backward at a lower speed (compared to the driving mode).

Obviously, the electric vehicle and the electrified power system it includes according to the present invention solve the defect of the inefficient use of the electric motor in the electrified power system of the prior art, and effectively improve the use efficiency of the electric motor in the electrified power system; The electric motor is used as the first electric motor, thereby reducing the cost of electrified power system and saving installation space.

Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the description, claims and drawings.

Description of drawings

The above and other features, advantages and aspects of various embodiments of the present invention will become more apparent when taken in conjunction with the accompanying drawings and with reference to the following detailed description. In the drawings, the same or similar reference numbers refer to the same or similar elements, wherein:

FIG. 1 is a schematic structural diagram of a conventional fuel power system of a street sweeper in the prior art.

FIG. 2 is a schematic structural diagram of an electrified power system of a street sweeper in the prior art.

FIG. 3( a ) is a schematic diagram illustrating a running mode of the electrified powertrain shown in FIG. 2 .

FIG. 3( b ) is a schematic diagram illustrating an operation mode of the electrified power system shown in FIG. 2 .

4 is a schematic structural diagram of an electrified power system of a street sweeper according to an embodiment of the present invention (utility model)

FIG. 5( a ) is a schematic diagram illustrating a running mode of the electrified powertrain shown in FIG. 4 .

FIG. 5( b ) is a schematic diagram illustrating an operation mode of the electrified power system shown in FIG. 4 .

Reference number:

1: Conventional fuel power system of prior art street sweeper

2: The electrified powertrain of the prior art street sweeper

3: The electrified power system of the street sweeper of the present invention

11, 21, 31: Travel unit

12, 22, 32: work unit

33: Power distribution device

111: chassis engine;

112, 122, 331: clutch;

113, 312: power transmission mechanism;

114, 313: Differential;

115, 314: Drive Wheels

121: auxiliary engine;

123, 322: work drive system;

124, 323: Cleaning equipment

1241, 3231: Exhaust fan

1242, 3232: brushes

211, 311: The first motor

221, 321: The second motor

332: Power take-off (PTO) switch

Detailed ways

Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for the purpose of A more thorough and complete understanding of the present invention. In other words, the drawings and embodiments of the present invention are only used for exemplary purposes, and are not used to limit the protection scope of the present invention.

As used throughout the specification of this application (including the claims), the term "connection" may refer to any direct or indirect means of connection. For example, if it is described in the text that a first device is connected to a second device, it should be interpreted that the first device can be directly connected to the second device, or the first device can be indirectly connected through other devices or some connection means connected to the second device. Terms such as "first" and "second" mentioned in the whole description (including the claims) of this application are used to name the device, or to distinguish different embodiments or scopes, or to facilitate the corresponding description and claims. It is not used to limit the upper or lower limit of the number of devices, nor is it used to limit the order of the devices. Additionally, where possible, elements/components/steps using the same reference numbers in the drawings and the detailed description represent the same or similar parts. Elements/components/steps using the same reference numerals or using the same terminology in different embodiments may refer to each other in the relevant descriptions.

FIG. 4 shows an electrified powertrain 3 for an electric vehicle according to a non-limiting embodiment of the present invention. In this embodiment, the electric vehicle is a street sweeper. The electrified power system 3 includes a travel unit 31 for propelling the street sweeper forward and backward, a work unit 32 for street sweeping, and a power split device 33 for power split/combination.

The traveling unit 31 includes a first electric motor 311 ; a power transmission mechanism 312 , whose input end is connected to the power output end of the first electric motor 311 ; a differential 313 whose input end is connected to the output end of the power transmission mechanism 312 . and drive wheels 314, which are connected with the output end of the differential 313 for driving the electric vehicle.

The operation unit 32 includes a second electric motor 321; a hydraulic system (ie, an operation drive system) 322, the input end of which is connected to the power output end of the second electric motor 321 through a power distribution device 33; and a sweeping device for cleaning streets (ie working equipment) 323, which is connected to the output end of the hydraulic system 322, and includes devices such as an exhaust fan 3231 and a brush 3232.

The first motor 311 and the second motor 321 are coaxially arranged.

The power distribution device 33 is a switching device, which is respectively connected with the first electric motor 311, the second electric motor 321 and the hydraulic system (ie, the work drive system) 322, and includes a clutch 331, which is arranged between the first electric motor 311 and the second electric motor 321. between and respectively connected with the input end of the first electric motor 311 and the output end of the second electric motor 321; and a power take-off (PTO) switch 332, which is arranged between the second electric motor 321 and the hydraulic system 322 and is respectively connected with The output end of the second electric motor 321 is connected to the input end of the hydraulic system 322 . Wherein, in the driving mode, the power distribution device 33 is in the first working state (ie, the clutch 331 is engaged and the PTO switch 332 is disconnected), so that the first electric motor 311 and the second electric motor 321 are connected in series, so that the first electric motor 311 and the PTO switch 332 are connected in series. The output power of the second electric motor 321 is combined for transmission to the power transmission mechanism 312; in the working mode, the power distribution device 33 is in the second working state (ie the clutch 331 is disengaged and the PTO switch 332 is closed) so that only the first electric motor The output power of 311 is supplied to the power transmission mechanism 312 , and only the output power of the second electric motor 321 is supplied to the hydraulic system 322 .

According to another embodiment of the present invention (not shown), the difference between the another embodiment and the embodiment shown in FIG. 4 is only that the electrified power system 3 further includes a control unit connected to the power distribution device 33 . , wherein, in the driving mode, the control unit makes the power distribution device 33 in the first working state (ie the clutch 331 is engaged and the PTO switch 332 is disconnected); in the working mode, the control unit makes the power distribution device 33 in the first working state Two working state 2 (ie clutch 331 is disengaged and PTO switch 332 is closed).

FIG. 5( a ) illustrates the driving mode of the electrified powertrain 3 of the embodiment shown in FIG. 4 . In the running mode, the power distribution device (switching device) 33 is in the first operating state, the clutch 331 is engaged and the PTO switch 332 is disconnected to connect the first electric motor 311 and the second electric motor 321 in series, so that the first electric motor 311 and the second electric motor 321 are connected in series. The output power of the second electric motor 321 is combined to transmit to the power transmission mechanism 312 so that the drive wheels 314 of the street sweeper are driven by the combined output power so that the street sweeper can move forward and backward at a higher speed.

FIG. 5( b ) illustrates the operation mode of the electrified power system 3 of the embodiment shown in FIG. 4 . In the working mode, the power distribution device (switching device) 33 is in the second working state, the clutch 331 is disengaged and the PTO switch 332 is closed so that only the output power of the first electric motor 311 is transmitted to the power transmission mechanism 312, thereby driving the street The sweeper moves forward and backward at low speed (compared to the travel mode); and only the output power of the second electric motor 321 is transmitted to the hydraulic system 322, thereby driving the sweeping device 323 to perform work to sweep the street.

In the above embodiment, the power distribution device 33 is a switching device, which is composed of a clutch 331 and a PTO switch 332. Of course, those skilled in the art can understand that the above embodiment is not limited, and the power distribution device of the present invention needs The function is to realize the first working state in the above-mentioned driving mode (the output power from the first electric motor and the second electric motor are combined through the power distribution device and then output to the power transmission mechanism, and the output power of the second electric motor is not provided to the work drive system) and the second working state in the work mode (so that only the output power of the first motor is provided to the power transmission mechanism, and only the output power of the second motor is provided to the work drive system), and according to different According to the application situation, the power distribution device can adopt other specific forms or structures to realize the two working states.

According to another embodiment (not shown) of the present invention, there is provided a street sweeping vehicle including the above-mentioned electrified power system 3 .

Compared with the prior art electrified power system 2 shown in FIG. 2 , in the electrified power system 3 according to the present invention, the designed maximum power of the first electric motor 311 can be much lower. Therefore, a smaller motor can be used as the first motor 311, thereby reducing cost and saving space. Furthermore, the layout shown in Figure 4 can achieve higher energy efficiency due to proper design and energy management strategies.

Obviously, the electric vehicle and the electrified power system it includes according to the present invention solve the defect of the inefficient use of the electric motor in the electrified power system of the prior art, and effectively improve the use efficiency of the electric motor in the electrified power system; The electric motor acts as the first electric motor, thereby reducing electrified powertrain costs and saving installation space.

The above-mentioned embodiments are described for street sweepers. Obviously, the technical solutions of the present invention are not limited to street sweepers, but are applicable to other types of electric vehicles including driving units and work units, including but not limited to various electric vehicles. a municipal vehicle or a construction vehicle.

In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

Finally, it should be noted that the above-mentioned embodiments are only specific implementations of the present invention, and are used to illustrate the technical solutions of the present invention, but not to limit them. The protection scope of the present invention is not limited thereto, although referring to the foregoing The present invention is described in detail by the embodiments, and those skilled in the art should understand that: any person skilled in the art can still modify the technical solutions described in the foregoing embodiments within the technical scope disclosed by the present invention. Or can easily think of changes, or equivalently replace some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be covered in the present invention. within the scope of protection. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

An electrified power system for an electric vehicle, the electrified power system includes a traveling unit for driving the electric vehicle to move forward and backward and a work unit for performing various operations, the traveling unit includes a first electric motor; a power transmission mechanism, the input end of which is connected to the power output end of the first electric motor; a differential, the input end of which is connected to the output end of the power transmission mechanism; and a drive wheel, which is connected to the The output end of the differential is connected to drive the electric vehicle to move forward and backward, and the work unit includes a second electric motor; the work drive system, the input end of which is connected to the power output of the second electric motor and the operation equipment, which is connected with the output end of the operation drive system and is used for performing various operations, and is characterized in that:

The electrified power system further includes a power distribution device connected to the first electric motor, the second electric motor and the work drive system, respectively, for outputting the first electric motor and the second electric motor power is distributed/combined to provide the power transmission mechanism and/or the work drive system,

Wherein, in the running mode, the power distribution device is in a first working state, so that the output power from the first electric motor and the second electric motor is combined through the power distribution device and then output to the power transmission mechanism , and the output power of the second electric motor is not provided to the work drive system,

wherein, in the working mode, the power distribution device is in a second working state so that only the output power from the first electric motor is provided to the power transmission mechanism, and only the output power from the second electric motor is provided to the work drive system.
The electrified power system according to claim 1, wherein the first electric motor and the second electric motor are arranged coaxially, and the power distribution device is a switching device provided between the first electric motor and the second electric motor between,

Wherein, in the running mode, the switching device is in the first working state to connect the first electric motor and the second electric motor in series, so as to make the output power of the first electric motor and the second electric motor is combined for transmission to the power transmission mechanism, and

Wherein, in the working mode, the switching device is in the second working state so that only the output power from the first electric motor is provided to the power transmission mechanism, and only the output power from the second electric motor is provided supplied to the work drive system.
The electrified power system of claim 2, wherein the switching device comprises:

a first switch disposed between the first motor and the second motor and connected to the input end of the first motor and the output end of the second motor, respectively; and

a second switch, disposed between the second motor and the work drive system and connected to the output end of the second motor and the input end of the work drive system, respectively,

Wherein, in the driving mode, the switching device is in the first working state, the first switch is closed and the second switch is opened to connect the first electric motor and the second electric motor in series , the output power of the first electric motor and the second electric motor is combined for transmission to the power transmission mechanism, and

wherein, in the operating mode, the switching device is in the second operating state, the first switch is opened and the second switch is closed so that only the output power from the first motor is provided to the The power transmission mechanism, and only the output power from the second electric motor, is provided to the work drive system.
The electrified power system according to any one of claims 1-3, wherein the electrified power system further comprises a control unit connected to the power distribution device, wherein, in a driving mode, the control unit The power distribution device is made to be in the first working state; in the working mode, the control unit makes the power distribution device be in the second working state.
The electrified power system of claim 3, wherein the first switch is a clutch and the second switch is a power take-off switch.
The electrified power system according to claim 1 or 2, wherein the electric vehicle is a street sweeper, the work drive system is a hydraulic system, and the work equipment is a cleaning equipment including devices such as an exhaust fan and a brush.
An electric vehicle comprising an electrified powertrain according to any one of claims 1 to 6.