KR102590424B1 - High efficiency driving system for vehicle - Google Patents

Abstract

The present invention is installed on a chassis 100 with wheels 110 and 120 installed at the front and rear, and supplies rotational driving force to the wheels by power supplied from a battery (not shown), improving driving performance and energy efficiency. It relates to an improved drive system for transportation, comprising a chassis 100 with wheels 110 and 120 installed at the front and rear, and a drive system 200 installed on the chassis 100 to supply rotational driving force to the wheels. In the electric vehicle including, the drive system 200 includes a housing 210 fixed to the chassis 100; A first electric motor 220 installed on one side of the housing 210 to supply rotational driving force; a second electric motor 230 installed on the other side of the housing 210 to supply rotational driving force; A first gear assembly 240 installed in the housing 210 and having a main input shaft 241a connected to the rotation shaft of the first electric motor 220 and an output shaft 244a that outputs increased torque; It is installed in the housing 210 and has a sub-input shaft 251a connected to the rotation axis of the second electric motor 230, and selectively transmits the rotational driving force of the second electric motor 230 to the first gear assembly 240. It is characterized in that it includes a second gear assembly 250.

Description

A driving system for transportation with improved driving performance and energy efficiency {High efficiency driving system for vehicle}

The present invention relates to a driving system that drives a vehicle using an electric motor as a driving source. More specifically, it travels by two electric motors when moving forward and by one electric motor when moving backward, thereby improving driving ability as well as energy efficiency. It relates to a drive system for transportation with improved driving performance and energy efficiency.

In general, internal combustion engines using engines have the characteristic of low torque at low RPM. Accordingly, in the case of cars using engines as a driving source, the engines are driven at high RPM to achieve high torque to overcome inertial resistance when starting. It had to be done. Accordingly, it is a well-known fact that fuel efficiency rapidly deteriorates due to excessive fuel consumption on complex roads with repeated stop-and-go traffic, and furthermore, excessive exhaust gas is generated in this process, causing environmental pollution.

Meanwhile, electric vehicles have recently been developed as a means of transportation using electric motors as a driving source and are rapidly becoming popular. Electric vehicles use a drive system implemented by combining an electric motor and a reducer as a driving source into one body.

Due to the nature of electric motors, they generate high torque even at low RPM, so they do not need to be driven at excessive RPM even on complex roads with repeated stops and stops, thereby minimizing energy consumption.

In addition, the RPM of an electric motor can be easily varied by controlling the applied power, so there is no need to use a transmission with a complicated structure, thereby reducing the possibility of a breakdown during operation. In addition, as no exhaust gases are emitted during operation, it is certain that it will replace internal combustion engine vehicles in the future.

When these electric vehicles drive on steep roads or drive at high speeds, high-output electric motors are used to achieve high torque.

However, in the case of high-output electric motors, a lot of electrical energy is basically consumed, which ultimately causes a decrease in the fuel efficiency of electric vehicles.

In addition, because high-output electric motors are large, the size of the reducer connected to them also had to be larger than necessary, which led to an increase in the weight of the electric vehicle and reduced energy efficiency.

The present invention was created to solve the above problems. It uses two relatively low-output electric motors, using both electric motors in the forward, incline, and high-speed sections, and one motor in the reverse and low-speed sections. The purpose is to provide a driving system for transportation with improved driving performance and energy efficiency that can reduce energy consumption and enable long-distance driving at the same time.

In order to achieve the above object, the driving system for transportation with improved driving performance and energy efficiency according to the present invention is installed on the chassis 100 on which wheels 110 and 120 are installed at the front and rear, and a battery ( A housing 210 that supplies rotational driving force to the wheels by power supplied from (not shown) and is fixed to the chassis 100; An electric vehicle comprising a chassis 100 with wheels 110 and 120 installed at the front and rear, and a drive system 200 installed on the chassis 100 to supply rotational driving force to the wheels, wherein the driving System 200 includes a housing 210 fixed to the chassis 100; A first electric motor 220 installed on one side of the housing 210 to supply rotational driving force; A second electric motor 230 installed on the other side of the housing 210 to supply rotational driving force; A first gear assembly 240 installed in the housing 210 and having a main input shaft 241a connected to the rotation shaft of the first electric motor 220 and an output shaft 244a that outputs increased torque; and a sub-input shaft 251a installed in the housing 210 and connected to the rotation axis of the second electric motor 230, and transmitting the rotational driving force of the second electric motor 230 to the first gear assembly 240. ) and a second gear assembly 250 that selectively transmits it to ).

In the present invention, the first gear assembly 240 includes a sun gear 241 having a main input shaft 241a protruding outward from the housing 210, and is arranged to surround the sun gear 241 in the circumferential direction. an inner ring gear 242, and a plurality of planetary gears 243 disposed between the sun gear 241 and the inner ring gear 242. It has an output shaft 244a protruding outward from the housing 210 on the opposite side of the main input shaft 241a and includes a carrier 244 connected to the rotation shaft of a plurality of planetary gears 243.

In the present invention, the first gear assembly 240 is coupled to the main input shaft 241a and is inserted into the first inner fitting groove 211a formed on the lower rear side of the first housing 211. A second inner fitting groove ( 212a) and rotatably supporting the carrier 244, which is coupled on both sides to the inner ring gear 242 and the first and second inner fitting grooves 211a ( It includes an outer bearing 247 that is inserted into the first and second outer fitting grooves 211b and 212b formed to be stepped on the outside of 212a) and rotatably supports the inner ring gear 242.

In the present invention, the second gear assembly 250 includes a sub-drive gear 251 having a sub-input shaft 251a protruding to the outside of the housing 210, and an outside of the inner ring gear 242. An outer ring gear 252 forming one body, an idler gear 253 having an overall ring shape as a connection between the sub-drive gear 251 and the outer ring gear 252, and the idler gear 253 It forms one body and includes a one-way bearing 254 that rotates in one direction, and a housing fixing shaft 255 that is axially coupled to the one-way bearing 254 and fixed to the first and second housings 211 and 212. do.

In the present invention, the one-way bearing 254 includes an inner ring 254a and an outer ring 254b that rotate relative to each other in one direction, and the outer ring 254b is an inner peripheral surface of the idler gear 253. It gets stuck non-rotatingly. The inner ring (254a) is non-rotatingly inserted into the housing fixing shaft (255).

In the present invention, the housing 210 includes a first housing 211 and a second housing 212 that form a space in which the first and second gear assemblies 240 and 250 are installed, and the first housing 212 A first housing stage 213 formed on the outside of the housing 211 and on which the first motor bracket 221 coupled to the tip of the first electric motor 220 is fixed, and the outside of the second housing 212 A second housing stage 214 on which the second motor bracket 231 coupled to the tip of the second electric motor 230 is fixed, and the first and second housings 211 and 212 are connected to the automobile chassis. It includes a housing fixing end (215) for fixing to (100).

In the present invention, the first and second housings 211 and 212 are formed on the lower side of the inner peripheral surface facing each other, and the first and second inner bearings 245 and 246 of the first gear assembly 240 are provided. The first and second inner fitting grooves 211a and 212a are inserted, and the outer bearing 247 of the first gear assembly 240 is formed outside the first and second inner fitting grooves 211a and 212a. First and second outer fitting grooves 211b and 212b, which are formed on the upper side, into which the upper bearing 256 of the second gear assembly 250 is inserted, and upper fitting grooves 211c and 212c, The outer ring 254b of the one-way bearing 254 that is formed between the upper fitting grooves 211c and 212c and the first and second outer fitting grooves 211b and 212b and constitutes the second gear assembly 250. ) is rotatably inserted into the middle fitting grooves 211d and 212d, and is formed on the inside of the middle fitting grooves 211d and 212d and is fixed to the inner ring 254a of the one-way bearing 254. It includes fixed shaft fixing grooves 211e and 212e into which the housing fixing shaft 255 is non-rotatingly inserted.

According to the present invention, by using the first and second gear assemblies 240 and 250, an electric vehicle can be driven at low or high speeds on a general road, and an electric car can be driven with a large torque on a high slope road, Stepless shifting is possible by controlling the operation of the second electric motor 230. When moving backwards, the second electric motor 230 can be stopped, thereby reducing unnecessary electric energy consumption.

In addition, as the sub-drive gear 251 has a large diameter and rotates the outer ring gear 252, a large torque is additionally generated in the outer ring gear 252 and the inner ring gear 242, and the additional torque is generated. Since is transmitted through the planetary gear 243 and the carrier 244, increased torque can ultimately be generated through the output shaft 244a.

In addition, the torque of the output shaft 244a is the sum of the torque of the first electric motor 220 and the torque of the second electric motor 230, and the rotational speed (RPM) of the output shaft 244a is that of the first electric motor 220. It is the sum of the rotation speed (RPM) and the rotation speed (RPM) of the second electric motor 230, and the transmission ratio of the output shaft 244a is determined by the torque of the first electric motor 220 and the torque of the second electric motor 230. It is decided by

In addition, by using two first and second electric motors (220) and (230) with lower output than the one electric motor used in existing electric vehicles, the size and weight of the drive system 200 can be reduced, Accordingly, it is possible to reduce the weight of electric vehicles, thereby reducing the electrical energy consumed, and at the same time, enabling long-distance driving.

1 is a diagram illustrating the application of the driving system for transportation with improved driving performance and energy efficiency according to the present invention to an electric vehicle;
Figure 2 is a perspective view showing an excerpt of the drive system installed on the chassis of Figure 1;
Figure 3 is a perspective view showing the first and second electric motors disassembled from both sides of the housing of Figure 2;
Figure 4 is a perspective view of the first and second gear assemblies installed in the housing of Figure 3;
Figure 5 is a diagram for explaining the detailed configuration of the housing of Figure 4;
Figure 6 is a perspective view for explaining the main parts of the first and second gear assemblies of Figure 4;
Figure 7 is an exploded perspective view of the idler gear, one-way bearing, and housing fixing shaft of Figure 6;
Figure 8 is a diagram for explaining bearings employed in the first and second gear assemblies of Figure 6;
Figure 9 is a perspective view of the first and second gear assemblies of Figure 8 seen from opposite directions.
FIG. 10 is a cross-sectional view taken along line VIII-VIII of FIG. 6, a diagram for explaining that the carrier connected to the rotation axis of the planetary gear rotates in the same direction due to rotation of the sun gear;
Figure 11 is a diagram for explaining that the rotational speed of the carrier increases when the rotational drive force of the second electric motor of Figure 10 is transmitted to the outer ring gear by the idler gear;
Figure 12 is a diagram for explaining that the outer ring gear is stopped by the one-way bearing when the sun gear of Figure 10 rotates in the opposite direction.

Hereinafter, a driving system for transportation with improved driving performance and energy efficiency according to the present invention will be described in detail with reference to the attached drawings.

Hereinafter, the term “above” or “above” may include not only what is directly above in contact but also what is above without contact. Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by the terms. Terms are used only to distinguish one component from another. Singular expressions include plural expressions unless the context clearly dictates otherwise. Additionally, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary. Additionally, terms such as "...unit" and "module" used in the specification refer to a unit that processes at least one function or operation.

1 is a diagram illustrating the application of the driving system for transportation with improved driving performance and energy efficiency according to the present invention to an electric vehicle.

As shown, the driving system for transportation with improved driving performance and energy efficiency according to the present invention is installed on the chassis 100 with wheels 110 and 120 installed at the front and rear and is operated by a battery (not shown). Rotational driving force is supplied to the wheels by the supplied power. The drive system 200 is exemplified as being directly or indirectly connected to the rear wheel 120 to supply rotational driving force.

For ease of explanation in this embodiment, the drive system 200 is exemplified as being directly or indirectly connected to the rear wheel 120 of the electric vehicle to supply rotational driving force.

Figure 2 is a perspective view showing an excerpt of the drive system installed in the chassis of Figure 1, Figure 3 is a perspective view showing the first and second electric motors disassembled from both sides of the housing of Figure 2, and Figure 4 is a diagram showing the first and second electric motors disassembled from both sides of the housing of Figure 2. This is a perspective view of the first and second gear assemblies installed in the housing.

The drive system 200 includes a housing 210 fixed to the chassis 100; A first electric motor 220 installed on one side of the housing 210 to supply rotational driving force; a second electric motor 230 installed on the other side of the housing 210 to supply rotational driving force; A first gear assembly 240 installed in the housing 210 and having a main input shaft 241a connected to the rotation shaft of the first electric motor 220 and an output shaft 244a that outputs increased torque; It is installed in the housing 210 and has a sub-input shaft 251a connected to the rotation axis of the second electric motor 230, and the rotational driving force of the second electric motor 230 is selectively applied to the first gear assembly 240. It includes a second gear assembly 250 that transmits to.

A first motor bracket 221 is coupled to the tip of the first electric motor 220 for fixing the first electric motor 220 to one side of the housing 210, and to the tip of the second electric motor 230. A second motor bracket 231 is coupled to secure the second electric motor 230 to the other side of the housing 210.

The first gear assembly 240 outputs increased torque through the output shaft 244a by reducing the rotational speed of the first electric motor 220 applied through the main input shaft 241.

The second gear assembly 250 selectively selects the rotational driving force of the second electric motor 230 applied through the sub-input shaft 251a to the first gear assembly 240 according to the rotation direction of the second electric motor 230. Pass it to

The output shaft 244a is directly or indirectly connected to the rear wheel 120 and transmits the rotational driving force of the first and second electric motors 220 and 230 to the rear wheel 120 to rotate the rear wheel 120, As a result, electric vehicles can be driven.

FIG. 5 is a diagram for explaining the detailed configuration of the housing of FIG. 4.

The housing 210 includes a first housing 211 and a second housing 212 that form a space inside which the first and second gear assemblies 240 and 250 are installed, and an outside of the first housing 211. A first housing stage 213 on which the first motor bracket 221 coupled to the tip of the first electric motor 220 is fixed, and a second electric motor formed on the outside of the second housing 212 ( 230), a second housing stage 214 on which the second motor bracket 231 is fixed, and a housing fixing end for fixing the first and second housings 211 and 212 to the automobile chassis 100. Includes (215).

When the first housing 211 and the second housing 212 are combined, they form a space in which the first and second gear assemblies 240 and 250 are installed. As shown in FIGS. 8 and 9, the first and second housings 211 and 212 are formed on the lower side of the inner circumferential surfaces facing each other and serve as the first and second inner bearings 245 of the first gear assembly 240. The first and second inner fitting grooves (211a) (212a) into which (246) are inserted, and the outer bearing (247) of the first gear assembly (240) are formed on the outside of the first and second inner fitting grooves (211a) (212a). ) are inserted into the first and second outer fitting grooves (211b) (212b), and upper fitting grooves (211c) (212c) formed on the upper side into which the upper bearing 256 of the second gear assembly 250 is inserted, and , the outer ring (254b) of the one-way bearing 254 that is formed between the upper fitting grooves (211c) (212c) and the first and second outer fitting grooves (211b) (212b) and constitutes the second gear assembly 250. This rotatable middle fitting groove (211d) (212d) is formed inside the middle fitting groove (211d) (212d) and is fixed to the inner ring (254a) of the one-way bearing (254). It includes fixed shaft fixing grooves 211e and 212e into which the shaft 255 is non-rotating.

The first and second housing stages 213 and 214 are formed to be stepped on the outside of the first and second housings 211 and 212 and provide a space for fixing the first and second electric motors 220 and 230. . A plurality of screw holes are formed in the first and second housing stages 213 and 214, and the bolts penetrating the first and second motor brackets 221 and 231 are fastened to the plurality of screw holes to form the first and second electric motors. (220) (230) are fixed to the first and second housing stages (213) (214).

By this housing 210, the first and second gear assemblies 240 and 250 and the first and second electric motors 220 and 230 are combined into one body, and at the same time, the first and second electric motors 220 A structural mechanism that can directly or indirectly connect 230 and the first and second gear assemblies 240 and 250 can be implemented.

Figure 6 is a perspective view for explaining the main parts of the first and second gear assemblies of Figure 4, and Figure 7 is an exploded perspective view of the idler gear, one-way bearing, and housing fixing shaft of Figure 6.

The first gear assembly 240 includes a sun gear 241 having a main input shaft 241a protruding to the outside of the housing 210, an inner ring gear 242 disposed circumferentially surrounding the sun gear 241, and , a plurality of planetary gears 243, for example, arranged between the sun gear 241 and the inner ring gear 242. It has an output shaft 244a protruding outward from the housing 210 on the opposite side of the main input shaft 241a and includes a carrier 244 connected to the rotation shaft of a plurality of planetary gears 243.

The sun gear 241, the inner ring gear 242, and the planetary gear 243 are implemented as helical gears with obliquely inclined teeth, and as a result, the engagement rate is good, rotation is smooth, and quiet compared to spur gears.

The main input shaft 241a is directly connected to the rotation shaft 220a of the first electric motor 220 and transmits the rotational driving force of the first electric motor 220 to the sun gear 241. At this time, a number of irregularities are formed on the outer peripheral surface of the first electric motor rotation shaft 220a, and the inner peripheral surface of the coupling groove 241b on the main input shaft 241a is engaged with the first electric motor rotation shaft 220a as shown in FIG. 8. By forming spline grooves, they can be coupled to each other in a non-rotating manner.

The planetary gear 243 meshes with the sun gear 241 on the inside of the inner ring gear 242 and revolves around the sun gear 241 when the sun gear 241 rotates.

The carrier 244 is simultaneously connected to the rotation shafts of a plurality of planetary gears 243, and thus rotates the output shaft 244a at the orbital speed of the planetary gears 243. This output shaft 244a is directly or indirectly connected to the rear wheel 120 and transmits a rotational driving force to rotate the rear wheel 120.

By this first gear assembly 240, the rotational driving force of the first electric motor 220 rotates the sun gear 241 through the main input shaft 241a, and the rotating sun gear 241 is connected to a plurality of planetary gears 243. ) while idling, the carrier 244 is rotated at a reduced speed, and the torque increased during the reduced rotation process is output through the output shaft 244a, and is transmitted to, for example, the rear wheel 120 of the electric vehicle to drive it.

The second gear assembly 250 includes a sub-drive gear 251 having a sub-input shaft 251a protruding to the outside of the housing 210, and an outer ring gear forming one body on the outside of the inner ring gear 242 ( 252), an idler gear 253 that connects the sub-drive gear 251 and the outer ring gear 252 and has an overall ring shape, and a circle that forms one body with the idler gear 253 and rotates in one direction. It includes a way bearing 254 and a housing fixing shaft 255 that is axially coupled to the one-way bearing 254 and fixed to the first and second housings 211 and 212.

The sub-drive gear 251, the idler gear 253, and the outer ring gear 252 are implemented as helical gears with obliquely inclined teeth, and as a result, the engagement rate is good, rotation is smooth, and quiet compared to spur gears.

The sub-input shaft 251a is directly connected to the rotation shaft of the second electric motor 230 and transmits the rotational driving force of the second electric motor 230 to the sub-drive gear 251 to rotate it.

The outer ring gear 252 forms one body with the inner ring gear 242 on the outside of the inner gear 242, and accordingly, the inner ring gear 242 is connected to the planetary gear 243 that engages and revolves with the sun gear 241. When rotated, they rotate together.

The idler gear 253 has an overall ring shape, and a wenway bearing 254 is inserted inside.

The one-way bearing 254 includes an inner ring 254a and an outer ring 254b that rotate relative to each other in one direction. The outer ring (254b) is non-rotatingly inserted into the inner peripheral surface of the idler gear (253). The inner ring (254a) is non-rotatingly inserted into the housing fixing shaft (255).

The housing fixing shaft 255 is fixed to the first and second housings 211 and 212 in a non-rotating state in the one-way bearing 254. The housing fixing shaft 255 is fixed to the one-way bearing 254. It includes a shaft body 255a that is non-rotatingly inserted, and a shaft extension end 255b that extends to both sides of the fixed shaft body 255a and is fixed to the first and second housings 211 and 212.

Here, the outer diameter d1 of the shaft body 255a is larger than the outer diameter d2 of the shaft extension end 255b, as shown in FIG. 7. Accordingly, even if the shaft extension ends 255b are formed on both sides of the shaft body 255a, the shaft extension ends 255b can penetrate the inner ring 254a of the one-way bearing 254.

There are various ways in which the idler gear 253 and the one-way bearing 254 are non-rotating with each other. In this embodiment, the first key protrusion 253b is formed on the inner peripheral surface 253a of the idler gear, and the first key protrusion 253b is formed on the outer side of the one-way bearing. It is illustrated that a first key groove 254c is formed in the ring 254b into which the first key protrusion 253b is inserted.

There are various ways in which the housing fixing shaft 255 and the one-way bearing 254 are non-rotating with each other. In this embodiment, a second key protrusion 254d is formed on the inner ring 254a of the one-way bearing, It is illustrated that a second key groove (255c) into which a second key protrusion (254d) is inserted is formed in the shaft body (255a) of the housing fixing shaft (255).

There are various ways of non-rotatingly inserting the housing fixing shaft 255 into the fixing shaft fixing grooves 211e and 212e of the first and second housings 211 and 212. In this embodiment, the axial extension end of the housing fixing shaft ( It is illustrated that spline protrusions are formed on the outer peripheral surface of 255b), and spline grooves are formed on the fixed shaft fixing grooves 211e and 212e.

By the one-way bearing 254, the outer ring gear 252 with which the idler gear 253 is engaged can be rotated in only one direction.

Figure 8 is a diagram for explaining bearings used in the first and second gear assemblies of Figure 6, and Figure 9 is a perspective view of the first and second gear assemblies of Figure 8 seen from the opposite direction.

The first gear assembly 240 is a first inner bearing that is coupled to the main input shaft 241a and is inserted into the first inner fitting groove 211a of the first housing 211 to rotatably support the sun gear 241. (245) and a second inner bearing 246 that is coupled to the carrier having the output shaft 244a and is inserted into the second inner fitting groove 212a of the second housing 212 to rotatably support the carrier 244. ) and an outer bearing 247 that is coupled to both sides of the inner ring gear 242 and is inserted into the first and second outer fitting grooves 211b and 212b to rotatably support the inner ring gear 242. It further includes.

The first inner bearing 245 is inserted into the first inner fitting groove 211a to rotatably support the sun gear 241, and the second inner bearing 246 is inserted into the second inner fitting groove 212a to support the carrier. A structural mechanism that rotatably supports (244) can be implemented.

The outer bearing 247 is inserted into the first and second outer fitting grooves 211b and 212b and rotatably supports the inner ring gear 242 and the outer ring gear 252, so that the first and second housings 211 ) A structural mechanism that can rotatably support the inner ring gear 242 and the outer ring gear 252 inside the first and second housings 211 and 212 without forming a hole through 212. It can be implemented.

Meanwhile, the second gear assembly 250 is coupled to the sub-input shaft 251a and is inserted into the upper fitting grooves 211c and 212c of the first and second housings 211 and 212 to form the sub-drive gear 251. It further includes an upper bearing 256 that rotatably supports. This upper bearing 256 is inserted into the upper fitting grooves 211c and 212c to rotatably support the sub-driving gear 251, so it does not form holes penetrating the first and second housings 211 and 212. It is possible to implement a structural mechanism that can rotatably support the sub-drive gear 251 inside the first and second housings 211 and 212.

FIG. 10 is a cross-sectional view taken along line VIII-VIII of FIG. 6, and is a view to explain that the carrier connected to the rotation axis of the planetary gear is rotated in the same direction by the rotation of the sun gear, and FIG. 11 is a view showing the second electric plane of FIG. 10. This is a diagram to explain that the rotational speed of the carrier increases when the rotational driving force of the motor is transmitted to the outer ring gear by the idler gear, and FIG. 12 shows the outer ring speed by the one-way bearing when the sun gear of FIG. 10 rotates in the opposite direction. This is a drawing to explain that the ring gear is stopped.

(a) When driving an electric vehicle at low speed on a general road,

The first electric motor 220 is operated and the second electric motor 230 is operated. Then, as shown in FIG. 10, the rotational driving force of the first electric motor 220 rotates the sun gear 241 clockwise through the first main input shaft 241a, and the rotation axis of the planetary gear 243 and the axis The coupled carrier (244 in FIG. 6) rotates in the same clockwise direction as the sun gear 241. In addition, the rotational driving force of the second electric motor 230 is transmitted to the outer ring gear 252 through the sub-drive gear 251 and the idler gear 253, and the inner ring gear forming one body with the outer ring gear 252 (242) adds torque output through the output shaft (244a) by transmitting the rotational driving force transmitted through the second electric motor 230 to the carrier 244 axially coupled to the planetary gear 243. By this operating mechanism, the torque output through the output shaft 244a of the carrier 244 rotates the rear wheels 120 at a low speed so that the electric vehicle can travel forward.

(b) When driving on a road at high speed or on a road that slopes upward,

Torque is increased by increasing the power applied to the first and second electric motors 220 and 230. then. As shown in FIG. 11, as a result, the electric vehicle can generate enough force to drive on a road at high speed or on a road that slopes upward.

(c) When changing the speed of an electric vehicle on a road while driving,

By controlling the power applied to the second electric motor 230, the magnitude of the rotational driving force is changed. Then, the rotational driving force of the second electric motor 230 is transmitted to the outer ring gear 252 through the sub-drive gear 251 and the idler gear 253. At this time, the rotational speed of the outer ring gear 252 is the second electric motor 252. Since it is dependent on the motor 230, the inner ring gear 242, which forms one body with the outer ring gear 252, can vary the rotational speed of the carrier 244 axially coupled to the planetary gear 243. Accordingly, the speed of the electric vehicle traveling on the road is changed.

(d) When the electric vehicle moves backwards,

As shown in FIG. 12, the first electric motor 220 is operated in the opposite direction to rotate the sun gear 241 counterclockwise, and in this case, the planetary gear 243 engaged with the sun gear 241 rotates in the opposite direction. As it rotates, the carrier 244 coupled to the rotation axis of the planetary gear 243 rotates counterclockwise. Accordingly, the torque output through the output shaft 244a of the carrier 244 rotates the rear wheels 120 in the opposite direction so that the electric vehicle can move backwards.

At this time, the outer ring gear 252 tries to rotate in the opposite direction compared to when the electric vehicle is traveling forward, but the idler gear 253 has a built-in one-way bearing 254 that rotates only in one direction, so the outer ring The gear 252 is maintained in a stopped state by the one-way bearing 254 and the idler gear 253, which is one body, and as a result, the operation of the second electric motor 230 can be completely stopped. That is, when moving backwards, the operation of the second electric motor 230 can be completely turned off.

In this way, by using the first and second gear assemblies 240 and 250, the electric vehicle can be driven at low or high speeds on general roads, and the electric car can be driven with large torque on high slope roads, and the second Stepless shifting is possible by controlling the operation of the electric motor 230. When moving backwards, the second electric motor 230 can be stopped, thereby reducing unnecessary electric energy consumption.

In addition, as the sub-drive gear 251 has a large diameter and rotates the outer ring gear 252, a large torque is additionally generated in the outer ring gear 252 and the inner ring gear 242, and the additional torque is generated. Since is transmitted through the planetary gear 243 and the carrier 244, increased torque can ultimately be generated through the output shaft 244a.

In addition, the torque of the output shaft 244a is the sum of the torque of the first electric motor 220 and the torque of the second electric motor 230, and the rotational speed (RPM) of the output shaft 244a is that of the first electric motor 220. It is the sum of the rotation speed (RPM) and the rotation speed (RPM) of the second electric motor 230, and the transmission ratio of the output shaft 244a is determined by the torque of the first electric motor 220 and the torque of the second electric motor 230. It is decided by

In addition, by using two first and second electric motors (220) and (230) with lower output than the one electric motor used in existing electric vehicles, the size and weight of the drive system 200 can be reduced, Accordingly, it is possible to reduce the weight of electric vehicles, thereby reducing the electrical energy consumed, and at the same time, enabling long-distance driving.

The present invention has been described with reference to an embodiment shown in the drawings, but this is merely illustrative, and those skilled in the art will understand that various modifications and other equivalent embodiments are possible therefrom.

100 ... Chassis 110, 120 ... Wheels
200 ... drive system 210 ... housing
211 ... first housing 211a, 212a ... first and second inner fitting grooves
211b, 212b ... outer fitting groove 211c, 212c ... upper fitting groove
211d, 212d ... middle fitting groove 211e, 212e ... fixed shaft fixing groove
213 ... 1st housing stage 214 ... 2nd housing stage
215 ... Housing fixing end 220 ... 1st electric motor
230 ... second electric motor 240 ... first gear assembly
241 ... sun gear 241a ... main input shaft
242 ... inner ring gear 243 ... planetary gear
244 ... carrier 244a ... output shaft
245 ... 1st inner bearing 246 ... 2nd inner bearing
247 ... Outer bearing 250 ... Second gear assembly
251 ... sub drive gear 251a ... sub input shaft
252 ... outer ring gear 253 ... idler gear
253a ... first key protrusion 254 ... one-way bearing
254a ... inner ring 254b ... outer ring
254c ... 1st key groove 254d ... 2nd key projection
255 ... housing fixed shaft 255a ... shaft body
255b ... shaft extension 255c ... second key groove

Claims (7)

It is installed on a chassis 100 with wheels 110 and 120 installed at the front and rear and supplies rotational driving force to the wheels by power supplied from a battery (not shown),
a housing 210 fixed to the chassis 100;
A first electric motor 220 installed on one side of the housing 210 to supply rotational driving force;
A second electric motor 230 installed on the other side of the housing 210 to supply rotational driving force;
A first gear assembly 240 installed in the housing 210 and having a main input shaft 241a connected to the rotation shaft of the first electric motor 220 and an output shaft 244a that outputs increased torque; and
It is installed in the housing 210 and has a sub-input shaft 251a connected to the rotation axis of the second electric motor 230, and the rotational driving force of the second electric motor 230 is applied to the first gear assembly 240. It includes a second gear assembly 250 that selectively transmits to;
The first gear assembly 240 includes a sun gear 241 having the main input shaft 241a protruding to the outside of the housing 210, and an inner ring gear disposed circumferentially surrounding the sun gear 241. (242) and a plurality of planetary gears (243) disposed between the sun gear (241) and the inner ring gear (242). A carrier 244 having an output shaft 244a protruding outside the housing 210 on the opposite side of the main input shaft 241a and connected to the rotation axis of the plurality of planetary gears 243, and a carrier 244 connected to the main input shaft 241a. A first inner bearing 245 that is coupled and is inserted into the first inner fitting groove 211a formed on the lower rear side of the first housing 211 of the housing 210 to rotatably support the sun gear 241. And, the output shaft 244a is coupled to the connected carrier and is inserted into the second inner fitting groove 212a formed on the lower rear side of the second housing 212 of the housing 210 to rotate the carrier 244. The second inner bearing 246, which supports the second inner bearing 246, is coupled to the inner ring gear 242 on both sides, and the first and second inner bearings 211a and 212a are steppedly formed on the outside of the first and second inner fitting grooves 211a and 212a. A means of transportation with improved driving performance and energy efficiency, characterized in that it includes an outer bearing 247 that is inserted into the outer fitting grooves 211b and 212b and rotatably supports the inner ring gear 242. delete delete The method of claim 1, wherein the second gear assembly 250 is:
A sub-drive gear 251 having a sub-input shaft 251a protruding to the outside of the housing 210,
An outer ring gear 252 forming a body outside the inner ring gear 242,
An idler gear 253 that connects the sub-drive gear 251 and the outer ring gear 252 and has an overall ring shape,
A one-way bearing (254) that forms one body with the idler gear (253) and rotates in one direction,
A drive for transportation with improved driving performance and energy efficiency, characterized in that it includes a housing fixing shaft 255 that is axially coupled to the one-way bearing 254 and fixed to the first and second housings 211 and 212. system. The method of claim 4, wherein the one-way bearing 254 is:
It includes an inner ring (254a) and an outer ring (254b) that rotate relative to each other in one direction, and the outer ring (254b) is non-rotatingly inserted into the inner peripheral surface of the idler gear (253). A drive system for transportation with improved driving performance and energy efficiency, wherein the inner ring (254a) is non-rotatingly inserted into the housing fixing shaft (255). The method of claim 5, wherein the housing 210 is:
A first housing 211 and a second housing 212 forming a space where the first and second gear assemblies 240 and 250 are installed,
A first housing stage 213 formed on the outside of the first housing 211 and on which the first motor bracket 221 coupled to the tip of the first electric motor 220 is fixed,
A second housing stage 214 formed on the outside of the second housing 212 and on which the second motor bracket 231 coupled to the tip of the second electric motor 230 is fixed,
A driving system for transportation with improved driving performance and energy efficiency, comprising a housing fixing end (215) for fixing the first and second housings (211) and (212) to the automobile chassis (100). The method of claim 5, wherein the first and second housings (211) (212) are,
First and second inner fitting grooves 211a and 212a formed on the lower side of the inner peripheral surface facing each other and into which the first and second inner bearings 245 and 246 of the first gear assembly 240 are inserted,
First and second outer fitting grooves (211b) (212b) formed outside the first and second inner fitting grooves (211a) (212a) into which the outer bearing 247 of the first gear assembly 240 is inserted,
Upper fitting grooves 211c and 212c formed on the upper side into which the upper bearing 256 of the second gear assembly 250 is inserted,
The outer ring 254b of the one-way bearing 254 that is formed between the upper fitting grooves 211c and 212c and the first and second outer fitting grooves 211b and 212b and constitutes the second gear assembly 250. ) are rotatably inserted into the middle fitting grooves (211d) (212d),
A fixed shaft fixing groove ( A driving system for transportation with improved driving performance and energy efficiency, comprising 211e) (212e).

Images