Low-speed sounding alarm device for electric automobile

Abstract

The invention discloses a low-speed sounding alarm device for an electric vehicle, and aims to provide a low-speed sounding alarm device which can not only meet the low-speed sounding alarm function, but also omit a complex alarm system, reduce the development cost, and avoid the influence on the driving experience due to the false operation of sounding alarm in the high-speed driving process of the electric vehicle caused by the fault of the alarm system. The low-speed sounding alarm device for the electric automobile is used for solving the problem. The motor comprises a motor rotating shaft; convex peaks are arranged on the outer wall of the sound steel ring; the knocking device is arranged on the motor rotating shaft and comprises a guide hole extending in the radial direction of the motor rotating shaft, a knocking piece capable of sliding along the guide hole and a spring, and the spring provides elastic force to drive the knocking piece to move towards the outer wall of the sound steel ring; when the speed of the electric automobile is smaller than a set value and the rotating shaft of the motor drives the knocking device to rotate, the knocking piece collides with the convex peak to generate knocking sound.

Description

Technical Field

[0001] The present invention relates to the technical field of electric drive assemblies of new energy vehicles, and in particular to a low-speed audible alarm device for an electric vehicle. Background Art

[0002] Electric vehicles (new energy vehicles) are relatively quiet when driving at low speeds (external noise is significantly lower than that of traditional internal combustion engine vehicles). When the vehicle is driving at low speeds, it is difficult for pedestrians outside the vehicle to detect the vehicle approaching through hearing, which makes it difficult for other pedestrians on the road to detect the approach of the vehicle, thus posing a greater safety hazard. In response to this, relevant regulations have formulated requirements for low-speed warning sounds for electric vehicles to remind pedestrians to pay attention to safety.

[0003] The current electric vehicle low-speed warning sound alarm system generally requires corresponding sound source data, adaptive software and processors for processing. The alarm system is complex and has high development costs. In addition, due to system failure, the electric vehicle may erroneously sound an alarm during high-speed driving, affecting the driving experience and even driving safety.

[0004] For example, the Chinese patent application number CN202110775034.8, the name of the invention is the intelligent control method and control device of the low-speed alarm sound of the automobile. The application adopts the method of judging the current position of the vehicle. If the current position is judged to be a non-point of interest area or the point of interest area is a non-crowded place, the vehicle's current driving speed and the information of pedestrians and non-motor vehicles around the vehicle are used to judge whether the low-speed alarm condition 2 is met. When the conditions are met, the low-speed alarm sound system is turned on and a sound reminder is issued. When the conditions are not met, the low-speed alarm sound system is turned off. It also has the problems of complex alarm system and high development cost; and there is a problem that due to system failure, the electric vehicle malfunctions in the process of high-speed driving, which affects the driving experience and even affects driving safety. Summary of the invention

[0005] The purpose of the present invention is to provide an electric vehicle low-speed sound alarm device which not only can meet the low-speed sound alarm function, but also eliminates the complex alarm system, reduces the development cost, and avoids the problem of false operation of the alarm system causing the electric vehicle to sound an alarm during high-speed driving, thereby affecting the driving experience and even affecting driving safety.

[0006] The technical solution of the present invention is: A low-speed sound alarm device for an electric vehicle, comprising: Motor shaft; The sound steel ring has a convex peak on its outer wall; A striking device is directly or indirectly arranged on the motor shaft, comprising a guide hole extending radially along the motor shaft, a striking piece that can slide along the guide hole, and a spring, wherein the spring provides elastic force to drive the striking piece to move toward the outer wall of the sound steel ring, and the side of the striking piece that faces the sound steel ring is a spherical surface or an arc surface; When the speed of the electric vehicle is less than a set value, the knocking device is driven by the motor shaft to rotate, and a knocking sound is generated by the collision between the knocking piece and the convex peak.

[0007] When the speed of the electric vehicle is greater than or equal to the set value, the motor shaft drives the knocking device to rotate, and the knocking piece moves away from the outer wall of the sound steel ring under the action of centrifugal force, so that there is no collision between the knocking piece and the convex peak. The specific operation of the low-speed sound alarm device of the electric vehicle of this scheme is as follows: during the driving of the electric vehicle, the motor shaft of the electric drive assembly drives the knocking piece to rotate synchronously. When the speed of the electric vehicle is less than the set value (that is, during the low-speed driving of the electric vehicle), the motor shaft drives the knocking device to rotate, and the action of the spring overcomes the centrifugal force of the knocking piece, so that the knocking piece collides with the convex peak to produce a knocking sound; at the same time, during the contact between the knocking piece and the convex peak, the knocking piece moves away from the sound steel ring and compresses the spring so that the knocking piece passes over the convex peak without affecting the normal operation of the electric drive assembly. When the speed of the electric vehicle is greater than or equal to the set value, the knocking piece moves away from the outer wall of the sound steel ring under the action of centrifugal force, so that there is no collision between the knocking piece and the peak, and no knocking sound is generated (the sound is cancelled at high speed), thereby satisfying the low-speed sound alarm function; at the same time, the low-speed sound alarm device of this scheme is a purely mechanical structure with a simple structure, safety and reliability. It not only eliminates the complex alarm system and reduces the development cost, but also avoids the malfunction of the alarm system causing the electric vehicle to issue a sound alarm during high-speed driving, which affects the driving experience and even affects driving safety.

[0008] Preferably, the motor shaft is the shaft of a drive motor of an electric vehicle.

[0009] Preferably, a rotary transformer cover is installed on the end cover of the driving motor, and a housing cavity is provided between the rotary transformer cover and the end cover, and the sound steel ring and the knocking device are located in the housing cavity. This scheme utilizes the characteristic of the existing motor assembly that there is a housing cavity between the rotary transformer cover and the end cover, and arranges the sound steel ring and the knocking device in the housing cavity, which can not only protect the low-speed sound alarm device, but also effectively improve the compactness of the structure and effectively reduce the modification of the original automobile parts. More importantly, the sound steel ring and the knocking device are arranged in the housing cavity. During the low-speed driving of the electric vehicle, the knocking alarm sound generated by the collision between the knocking piece and the convex peak can be directly transmitted to the outside of the vehicle through the rotary transformer cover, so as to alert pedestrians; and there is an internal partition and vibration isolation effect from the electric drive to the whole vehicle, so that the knocking alarm sound is difficult to be transmitted to the inside of the vehicle, which can effectively reduce the impact on the people in the vehicle.

[0010] Preferably, the acoustic steel ring is fixedly arranged on the rotary transformer cover of the electric vehicle. In this way, on the one hand, the fixing and arrangement of the acoustic steel ring is convenient, and on the other hand, when the electric vehicle is driving at a low speed, the knocking alarm sound generated by the collision between the knocking piece and the convex peak can be directly transmitted to the outside of the vehicle through the rotary transformer cover to alert pedestrians.

[0011] Preferably, the knocking device further comprises a guide sleeve and an adjusting bolt, the inner hole of the guide sleeve constitutes the guide hole, the adjusting bolt and the guide hole are connected by threads, and the spring is located in the guide hole between the knocking piece and the adjusting bolt. In this way, the initial pre-tightening force of the spring on the knocking piece can be adjusted by tightening or loosening the adjusting bolt, thereby adapting to the low-speed sound alarm function at different driving speeds.

[0012] Preferably, a limit column is provided on the end of the adjusting bolt facing the striking piece, the limit column is inserted in the spring, and a distance is provided between the limit column and the striking piece. In this way, the limit column can be used to limit the stroke of the striking piece moving away from the sound steel ring, so as to prevent the striking piece from being too centrifugal and crushing the spring during high-speed driving of the electric vehicle.

[0013] Preferably, a closing structure with a reduced inner diameter is provided at one end of the guide hole facing the outer wall of the acoustic steel ring, and the closing structure, the striking piece, the spring and the adjusting bolt are sequentially distributed along the axial direction of the guide hole. In this way, the striking piece can be prevented from falling out of the guide hole, which is convenient for actual production.

[0014] Preferably, the knocking member is a knocking ball. Thus, when the electric vehicle is running at a low speed, when the knocking ball contacts and collides with the convex peak, the knocking ball can roll, thereby effectively reducing the friction resistance between the knocking ball and the convex peak.

[0015] As a preference, the motor further comprises a mounting bracket, the mounting bracket being fixed on the motor shaft, and the knocking device being mounted on the mounting bracket, so as to facilitate the installation and manufacture of the knocking device.

[0016] The beneficial effects of the present invention are: First, it can meet the low-speed sound alarm function.

[0017] Secondly, it adopts a purely mechanical structure with a simple structure, safety and reliability, eliminating the need for a complex alarm system, reducing development costs, and avoiding the problem of false operation of the alarm system causing the electric vehicle to sound an alarm during high-speed driving, which affects the driving experience and even driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The utility model is a partial cross-sectional structural schematic diagram of a low-speed sound alarm device for an electric vehicle of the present invention.

[0019] Figure 2 The present invention is a schematic diagram of a partial cross-sectional structure of a low-speed sound alarm device for an electric vehicle after removing an end cover of a driving motor.

[0020] Figure 3 The invention discloses an exploded view of a low-speed sound alarm device for an electric vehicle.

[0021] In the figure: Motor shaft 1; Acoustic steel ring 2, convex peak 2.1; A striking device 3, a guide sleeve 3.1, a striking member 3.2, a spring 3.3, an adjusting bolt 3.4, a limiting column 3.5, and a closing structure 3.6; Mounting bracket 4, main body 4.1, end plate 4.2, connecting sleeve 4.3, mounting hole 4.4; Rotary cover plate 5; End cap 6; Accommodating cavity 7. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments: Specific embodiment 1, as Figure 1 , Figure 2 As shown, a low-speed sound alarm device for an electric vehicle includes a motor shaft 1, a sound steel ring 2 and a knocking device 3. In this embodiment, the motor shaft 1 is the shaft of the driving motor of the electric vehicle. The sound steel ring 2 is fixedly arranged, and a convex peak 2.1 is provided on the outer wall of the sound steel ring 2. It should be noted that the sound steel ring 2 in the claims of the present application does not specifically refer to a steel sound steel ring 2, which includes but is not limited to a steel sound steel ring 2, an aluminum sound steel ring 2, a copper sound steel ring 2, and can also be a sound steel ring 2 made of alloys such as aluminum alloy and copper alloy, or a sound steel ring 2 made of other metal materials. The knocking device 3 is directly or indirectly arranged on the motor shaft 1. During the driving process of the electric vehicle, the motor shaft 1 of the electric drive assembly drives the knocking member 3.2 to rotate synchronously. The knocking device 3 includes a guide hole extending radially along the motor shaft 1, a knocking member 3.2 that can slide along the guide hole, and a spring 3.3. The spring 3.3 provides elastic force to drive the knocking piece 3.2 to move toward the outer wall of the sound steel ring 2, and the side of the knocking piece 3.2 facing the sound steel ring 2 is a spherical surface or an arc surface.

[0023] When the speed of the electric vehicle is less than the set value v, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 collides with the convex peak 2.1 to produce a knocking sound. For example, when the speed of the electric vehicle is less than 30 km / h, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 collides with the convex peak 2.1 to produce a knocking sound.

[0024] When the speed of the electric vehicle is greater than or equal to the set value v, the motor shaft 1 drives the striking device 3 to rotate, and the striking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that the striking piece 3.2 does not collide with the convex peak 2.1. For example, when the speed of the electric vehicle is greater than or equal to 30 km / h, the motor shaft 1 drives the striking device 3 to rotate, and the striking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that the striking piece 3.2 does not collide with the convex peak 2.1.

[0025] The specific operation of the low-speed sound alarm device for electric vehicles of this embodiment is as follows: during the driving of the electric vehicle, the motor shaft 1 of the electric drive assembly drives the knocking member 3.2 to rotate synchronously. When the speed of the electric vehicle is less than the set value v (i.e., during the low-speed driving of the electric vehicle), during the process of the motor shaft 1 driving the knocking device 3 to rotate, the force of the spring 3.3 overcomes the centrifugal force of the knocking member 3.2, so that the knocking member 3.2 collides with the convex peak 2.1 to produce a knocking sound; at the same time, during the contact between the knocking member 3.2 and the convex peak 2.1, the knocking member 3.2 moves away from the sound steel ring 2 and compresses the spring 3.3 so that the knocking member 3.2 passes over the convex peak 2.1 without affecting the normal operation of the electric drive assembly. When the speed of the electric vehicle is greater than or equal to the set value v, the knocking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that there is no collision between the knocking piece 3.2 and the peak 2.1, and no knocking sound is generated (the sound is cancelled at high speed), thereby satisfying the low-speed sound alarm function; at the same time, the low-speed sound alarm device of this scheme is a purely mechanical structure with a simple structure, safety and reliability, which not only eliminates the complex alarm system and reduces the development cost, but also avoids the malfunction of the alarm system causing the sound alarm to be induced during high-speed driving of the electric vehicle, thereby affecting the driving experience and even affecting the driving safety.

[0026] Specific embodiment 2, as Figure 1 , Figure 2 , Figure 3 As shown, a low-speed sound alarm device for an electric vehicle comprises a motor shaft 1, a sound steel ring 2 and a knocking device 3. In this embodiment, the motor shaft 1 is the shaft of the driving motor of the electric vehicle.

[0027] The acoustic steel ring 2 is fixedly arranged. It should be noted that the acoustic steel ring 2 in the claims of the present application does not specifically refer to a steel acoustic steel ring 2, which includes but is not limited to a steel acoustic steel ring 2, an aluminum acoustic steel ring 2, a copper acoustic steel ring 2, and may also be an acoustic steel ring 2 made of alloys such as aluminum alloy, copper alloy, or an acoustic steel ring 2 made of other metal materials.

[0028] In this embodiment, the acoustic steel ring 2 is coaxially distributed with the motor shaft 1. A convex peak 2.1 is provided on the outer wall of the acoustic steel ring 2. The outer side surface of the convex peak 2.1 is a cylindrical surface, or the convex peak 2.1 is hemispherical.

[0029] In one embodiment, a convex peak 2.1 is provided on the outer wall of the acoustic steel ring 2.

[0030] In another embodiment, the outer wall of the acoustic steel ring 2 is provided with a plurality of convex peaks 2.1 evenly distributed around the circumference of the acoustic steel ring 2. For example, the outer wall of the acoustic steel ring 2 is provided with 2-6 convex peaks 2.1 evenly distributed around the circumference of the acoustic steel ring 2. According to the matching characteristics of different vehicle models, a unique sound effect style can be formed by designing the convex peaks 2.1 of the acoustic steel ring 2.

[0031] The knocking device 3 is directly or indirectly arranged on the motor shaft 1. In this embodiment, the knocking device 3 is located on the outside of the sound steel ring 2. During the driving of the electric vehicle, the motor shaft 1 of the electric drive assembly drives the knocking piece 3.2 to rotate synchronously. The knocking device 3 includes a guide hole extending radially along the motor shaft 1, a knocking piece 3.2 that can slide along the guide hole, and a spring 3.3. The spring 3.3 provides an elastic force to drive the knocking piece 3.2 to move toward the outer wall of the sound steel ring 2, and the side of the knocking piece 3.2 facing the sound steel ring 2 is a spherical or arc surface.

[0032] In one embodiment, there is one striking device 3 .

[0033] In another embodiment, there are multiple knocking devices 3, and each knocking device 3 is evenly distributed in sequence around the circumference of the motor shaft 1. The specific number of the knocking devices 3 can be arranged as needed, for example, the number of the knocking devices 3 is 3, 4, 5 or more. According to the matching characteristics of different vehicle models, a unique sound effect style can be formed by designing the number of the knocking devices 3.

[0034] When the speed of the electric vehicle is less than the set value v, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 collides with the convex peak 2.1 to produce a knocking sound. For example, when the speed of the electric vehicle is less than 30 km / h, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 collides with the convex peak 2.1 to produce a knocking sound.

[0035] In one embodiment, when the electric vehicle stops and the motor shaft 1 stops rotating, the knocking member 3.2 abuts against the outer wall of the acoustic steel ring 2 under the action of the spring 3.3.

[0036] In another embodiment, when the electric car stops and the motor shaft 1 stops rotating, there is a gap between the knocking member 3.2 and the outer wall of the sound steel ring 2, and the gap is smaller than the height of the protrusion 2.1.

[0037] When the speed of the electric vehicle is greater than or equal to the set value v, the motor shaft 1 drives the striking device 3 to rotate, and the striking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that the striking piece 3.2 does not collide with the convex peak 2.1. For example, when the speed of the electric vehicle is greater than or equal to 30 km / h, the motor shaft 1 drives the striking device 3 to rotate, and the striking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that the striking piece 3.2 does not collide with the convex peak 2.1.

[0038] Of course, it should be noted that the above-mentioned setting value v can be set according to actual needs, for example, the setting value v can be set to 20 km / h, 25 km / h, 35 km / h or 40 km / h.

[0039] The specific operation of the low-speed sound alarm device for electric vehicles of this embodiment is as follows: during the driving of the electric vehicle, the motor shaft 1 of the electric drive assembly drives the knocking member 3.2 to rotate synchronously. When the speed of the electric vehicle is less than the set value v (i.e., during the low-speed driving of the electric vehicle), during the process of the motor shaft 1 driving the knocking device 3 to rotate, the force of the spring 3.3 overcomes the centrifugal force of the knocking member 3.2, so that the knocking member 3.2 collides with the convex peak 2.1 to produce a knocking sound; at the same time, during the contact between the knocking member 3.2 and the convex peak 2.1, the knocking member 3.2 moves away from the sound steel ring 2 and compresses the spring 3.3 so that the knocking member 3.2 passes over the convex peak 2.1 without affecting the normal operation of the electric drive assembly. When the speed of the electric vehicle is greater than or equal to the set value v, the knocking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that there is no collision between the knocking piece 3.2 and the peak 2.1, and no knocking sound is generated (the sound is cancelled at high speed), thereby satisfying the low-speed sound alarm function; at the same time, the low-speed sound alarm device of this scheme is a purely mechanical structure with a simple structure, safety and reliability, which not only eliminates the complex alarm system and reduces the development cost, but also avoids the malfunction of the alarm system causing the sound alarm to be induced during high-speed driving of the electric vehicle, thereby affecting the driving experience and even affecting the driving safety.

[0040] like Figure 1 , Figure 2 As shown, the knocking device 3 is directly or indirectly arranged on the motor shaft 1. In this embodiment, the knocking device 3 is indirectly arranged on the motor shaft 1. Specifically, an electric vehicle low-speed sound alarm device also includes a mounting bracket 4. The mounting bracket 4 is fixed on the motor shaft 1. The knocking device 3 is installed on the mounting bracket 4 (that is, the knocking device 3 is indirectly arranged on the motor shaft 1 through the mounting bracket 4). In this way, the installation and production of the knocking device 3 is facilitated.

[0041] In one example, if Figure 2 , Figure 3As shown, the mounting bracket 4 includes a cylindrical main body 4.1 and an end plate 4.2 arranged at one end of the cylindrical main body 4.1, and a connecting sleeve 4.3 is arranged on the end plate 4.2, and the connecting sleeve 4.3 is coaxially distributed with the cylindrical main body 4.1. One end of the motor shaft 1 is inserted into the connecting sleeve 4.3, and the motor shaft 1 and the connecting sleeve 4.3 are connected by bolts, threads, rivets or welding. The side wall of the cylindrical main body 4.1 is provided with mounting holes 4.4 corresponding to the knocking device 3, and the knocking device 3 is installed in the corresponding mounting holes 4.4.

[0042] In another example, the mounting bracket 4 includes a connecting sleeve and a mounting piece fixedly connected to the outer wall of the connecting sleeve, one end of the motor shaft 1 is inserted into the connecting sleeve, and the motor shaft 1 is connected to the connecting sleeve by bolts, threads, rivets or welding. The knocking device 3 corresponds to the mounting piece one by one, and the knocking device 3 is installed on the corresponding mounting piece.

[0043] Further, such as Figure 2 , Figure 3 As shown, the knocking device 3 also includes a guide sleeve 3.1. The inner hole of the guide sleeve 3.1 constitutes the guide hole. The guide sleeve 3.1 is installed on the mounting bracket 4, so that the knocking device 3 is installed on the mounting bracket 4. In this way, the installation and production of the knocking device 3 is facilitated.

[0044] Further, such as Figure 2 , Figure 3 As shown, the knocking device 3 also includes an adjusting bolt 3.4. The adjusting bolt 3.4 is connected to the guide hole by a thread, and the spring 3.3 is located in the guide hole between the knocking piece 3.2 and the adjusting bolt 3.4. In this way, the initial pre-tightening force of the spring 3.3 on the knocking piece 3.2 can be adjusted by tightening or loosening the adjusting bolt 3.4, thereby adapting to the low-speed sound alarm function at different driving speeds.

[0045] Further, such as Figure 2 , Figure 3 As shown, a limit column 3.5 is also provided on the end of the adjusting bolt 3.4 facing the striking piece 3.2, and the limit column 3.5 is inserted into the spring 3.3, and a distance is provided between the limit column 3.5 and the striking piece 3.2. In this way, the limit column 3.5 can limit the stroke of the striking piece 3.2 moving away from the sound steel ring 2, thereby preventing the striking piece 3.2 from being too centrifugal and crushing the spring 3.3 during high-speed driving of the electric vehicle.

[0046] The limiting column 3.5 and the adjusting bolt 3.4 are coaxially distributed.

[0047] In one embodiment, the limiting column 3.5 is fixedly connected to the adjusting bolt 3.4, for example, the limiting column 3.5 and the adjusting bolt 3.4 are integrally formed, or the limiting column 3.5 and the adjusting bolt 3.4 are connected by welding, so as to facilitate the manufacture of the limiting column 3.5 and the adjusting bolt 3.4.

[0048] In another embodiment, a bolt hole is further provided on the end of the adjusting bolt 3.4 facing the striking member 3.2, and the limiting column 3.5 is threadedly connected to the bolt hole. In this way, the spacing between the limiting column 3.5 and the striking member 3.2 can be adjusted by rotating the limiting column 3.5.

[0049] Further, such as Figure 2 As shown, a closing structure 3.6 with a reduced inner diameter is provided at one end of the guide hole facing the outer wall of the acoustic steel ring 2, and the closing structure 3.6, the striking piece 3.2, the spring 3.3 and the adjusting bolt 3.4 are sequentially distributed along the axial direction of the guide hole. In this way, the striking piece 3.2 can be prevented from falling out of the guide hole, which is convenient for actual production.

[0050] In one example, the inner side surface of the closing structure 3.6 and the annular arc surface, and the annular arc surface and the inner wall of the guide hole are smoothly transitioned.

[0051] In another example, the closing structure is an annular protrusion, and a step is provided between the annular protrusion and the inner wall of the guide hole.

[0052] If the electric car stops and the motor shaft 1 stops rotating, there is a gap between the knocking piece 3.2 and the outer wall of the sound steel ring 2. At this time, the knocking piece 3.2 is pressed against the closing structure under the action of the spring 3.3 to prevent the knocking piece 3.2 from falling out of the guide hole.

[0053] The specific form of the knocking member 3.2 can be designed and manufactured as required, for example, In one embodiment, if Figure 2 , Figure 3 As shown, the striking member 3.2 is a striking ball. The striking ball is a metal ball, such as a steel ball, an aluminum ball, a copper ball, or a ball made of an alloy such as an aluminum alloy or a copper alloy. In this way, when the striking ball and the convex peak 2.1 come into contact and collide during low-speed driving of the electric vehicle, the striking ball can roll, thereby effectively reducing the friction resistance between the striking ball and the convex peak 2.1.

[0054] In another embodiment, the knocking piece 3.2 is cylindrical (not shown in the figure). The end of the knocking piece 3.2 facing the acoustic steel ring 2 is spherical or arc-shaped.

[0055] Further, such as Figure 1As shown, a rotary transformer cover plate 5 is installed on the end cover 6 of the driving motor, and a receiving cavity 7 is provided between the rotary transformer cover plate 5 and the end cover 6. The sound steel ring 2 and the knocking device 3 are located in the receiving cavity 7. This solution utilizes the characteristic that there is a receiving cavity 7 between the rotary transformer cover plate 5 and the end cover 6 in the existing motor assembly, and arranges the sound steel ring 2 and the knocking device 3 in the receiving cavity 7, which can not only protect the low-speed sound alarm device, but also effectively improve the compactness of the structure, effectively reduce the modification of the original automobile parts, and realize the installation requirements through very small size modification, and the overall structure modification is small, which further reduces the development cost. More importantly, the sound steel ring 2 and the knocking device 3 are arranged in the accommodating cavity 7. When the electric vehicle is driving at a low speed, the knocking alarm sound generated by the collision between the knocking member 3.2 and the convex peak 2.1 can be directly transmitted to the outside of the vehicle through the rotary cover plate 5, so as to alert pedestrians; and there is an internal partition and vibration isolation effect from the electric drive to the whole vehicle, and the knocking alarm sound is difficult to be transmitted into the vehicle, which can effectively reduce the impact on the people in the vehicle.

[0056] In one embodiment, if Figure 1 , Figure 2 , Figure 3 As shown, the acoustic steel ring 2 is fixedly arranged on the rotary transformer cover plate 5 of the electric vehicle. In this way, on the one hand, the fixing and arrangement of the acoustic steel ring 2 is convenient, and on the other hand, when the electric vehicle is running at a low speed, the knocking alarm sound generated by the collision between the knocking member 3.2 and the convex peak 2.1 can be directly transmitted to the outside of the vehicle through the rotary transformer cover plate 5, so as to alert pedestrians.

[0057] In one example, the acoustic steel ring 2 and the rotary transformer cover plate 5 are integrally formed, so that the structure between the acoustic steel ring 2 and the rotary transformer cover plate 5 is guaranteed to be stable and easy to install.

[0058] In another example, the acoustic steel ring 2 and the rotary cover plate 5 are made separately, and the acoustic steel ring 2 and the rotary cover plate 5 are fixed on the rotary cover plate 5 of the electric vehicle by welding, bolts, threads, or riveting. In this way, the acoustic steel ring 2 can be added to the original rotary cover plate 5 without changing the original manufacturing mold of the rotary cover plate 5.

[0059] In another embodiment, the acoustic steel ring is fixed to the end cover of the driving motor through a mounting member (not shown in the figure).

[0060] Specific embodiment 3, a design method of a low-speed sound alarm device for an electric vehicle. The specific structure of the low-speed sound alarm device for an electric vehicle in this embodiment refers to specific embodiment 2.

[0061] A design method for a low-speed sound alarm device for an electric vehicle is as follows: First, determine the vehicle speed and the speed ratio of the electric drive assembly at the set value v.

[0062] Second, the rotation speed of the motor shaft 1 of the driving motor of the electric drive assembly is calculated through the vehicle speed of the electric vehicle (ie, the set value v) and the speed ratio of the electric drive assembly transmission system.

[0063] Third, determine the rotation speed of the knocking member 3.2 according to the rotation speed of the motor shaft 1 (the rotation speed of the motor shaft 1 is the same as the rotation speed of the knocking member 3.2), determine the mass m of the knocking member 3.2, and determine the rotation radius of the knocking member 3.2; then calculate the centrifugal force of the steel ball.

[0064] Fourth, determine the size of the peak 2.1 of the acoustic steel ring 2 and the matching size between the striking piece 3.2 and the peak 2.1 (i.e., when the speed of the electric vehicle is less than the set value v, the motor shaft 1 drives the striking device 3 to rotate, and the matching size of the collision between the striking piece 3.2 and the peak 2.1).

[0065] Fifth, the model parameters of the spring 3.3 are determined by the calculated centrifugal force of the steel ring and the matching size of the knocking piece 3.2 and the convex peak 2.1, so as to achieve, When the speed of the electric vehicle is less than the set value v, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 collides with the convex peak 2.1 to produce a knocking sound; for example, when the speed of the electric vehicle is less than 30 km / h, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 collides with the convex peak 2.1 to produce a knocking sound; When the speed of the electric vehicle is greater than or equal to the set value v, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that there is no collision between the knocking piece 3.2 and the convex peak 2.1; for example, when the speed of the electric vehicle is greater than or equal to 30km / h, the motor shaft 1 drives the knocking device 3 to rotate, and the knocking piece 3.2 moves away from the outer wall of the sound steel ring 2 under the action of centrifugal force, so that there is no collision between the knocking piece 3.2 and the convex peak 2.1, and the sound disappears.

[0066] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A low-speed sound alarm device for electric vehicles, characterized in that: include: Motor shaft; The sound steel ring has a convex peak on its outer wall; A striking device is directly or indirectly arranged on the motor shaft, comprising a guide hole extending radially along the motor shaft, a striking piece that can slide along the guide hole, and a spring, wherein the spring provides elastic force to drive the striking piece to move toward the outer wall of the sound steel ring, and the side of the striking piece that faces the sound steel ring is a spherical surface or an arc surface; When the speed of the electric vehicle is less than a set value, the knocking device is driven by the motor shaft to rotate, and a knocking sound is generated by the collision between the knocking piece and the convex peak.

2. The electric vehicle low-speed sound alarm device according to claim 1 is characterized in that: When the speed of the electric vehicle is greater than or equal to the set value, the motor shaft drives the striking device to rotate, and the striking piece moves away from the outer wall of the sound steel ring under the action of centrifugal force to prevent the striking piece from colliding with the convex peak.

3. The low-speed sound alarm device for electric vehicles according to claim 1 or 2, characterized in that: The motor shaft is the shaft of the driving motor of the electric vehicle.

4. The low-speed sound alarm device for electric vehicles according to claim 3 is characterized in that: A rotary transformer cover plate is installed on the end cover of the driving motor, and a receiving cavity is provided between the rotary transformer cover plate and the end cover, and the sound steel ring and the knocking device are located in the receiving cavity.

5. The low-speed sound alarm device for electric vehicles according to claim 4 is characterized in that: The acoustic steel ring is fixedly arranged on the rotary transformer cover plate of the electric vehicle.

6. The low-speed sound alarm device for electric vehicles according to claim 1 or 2, characterized in that: The knocking device also includes a guide sleeve and an adjusting bolt. The inner hole of the guide sleeve constitutes the guide hole. The adjusting bolt and the guide hole are connected by threads. The spring is located in the guide hole between the knocking piece and the adjusting bolt.

7. The low-speed sound alarm device for electric vehicles according to claim 6 is characterized in that: A limiting column is also provided on one end of the adjusting bolt facing the knocking piece. The limiting column is inserted in the spring, and a distance is provided between the limiting column and the knocking piece.

8. The low-speed sound alarm device for electric vehicles according to claim 7 is characterized in that: An end of the guide hole facing the outer wall of the acoustic steel ring is provided with a closing structure with a reduced inner diameter, and the closing structure, the knocking piece, the spring and the adjusting bolt are sequentially distributed along the axial direction of the guide hole.

9. The electric vehicle low-speed sound alarm device according to claim 1 or 2, characterized in that: The striking piece is a striking ball.

10. The electric vehicle low-speed sound alarm device according to claim 1 or 2, characterized in that: It also includes a mounting bracket, which is fixed on the motor shaft, and the knocking device is installed on the mounting bracket.

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