Patent Publication Number: US-2023159009-A1

Title: Braking mode switching apparatus and brake control system for vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Chinese Patent Application No. 202111415849.1, filed on Nov. 25, 2021, which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The embodiments relate to the vehicle field, a braking mode switching apparatus, and a brake control system for a vehicle. 
     BACKGROUND 
     As a service life of a vehicle increases, an electrical system of the vehicle may become faulty. This brings a serious potential risk to driving of the vehicle. In particular, when the electrical system that becomes faulty is associated with safety performance (for example, braking performance) of the vehicle, such a failure is usually fatal. Therefore, how to ensure driving safety even if the electrical system of the vehicle is faulty is an important challenge. 
     SUMMARY 
     The embodiments may provide a braking mode switching apparatus and a brake control system for a vehicle, to overcome at least some of the foregoing problem and/or another potential problem existing in the conventional technology. 
     According to a first aspect, a braking mode switching apparatus is provided. The braking mode switching apparatus includes: a braking mode selection component, where the braking mode selection component can move between a first position corresponding to a first braking mode and a second position corresponding to a second braking mode; a transmission member, where the transmission member is coupled to the braking mode selection component and has a first transmission portion and a second transmission portion; a stopper, including a first stopper portion and a second stopper portion; and a driver, including an output shaft; and a motion control component, disposed on the output shaft and coupled to the braking mode selection component. The motion control component is configured to: abut against the first stopper portion in response to a case in which the driver is powered on, where the braking mode selection component is located in the first position, so that the first transmission portion engages with a first execution portion; and abut against the second stopper portion in response to a case in which the driver is not powered on, where the braking mode selection component is located in the second position, so that the second transmission portion engages with a second execution portion. 
     According to the embodiments, the transmission member may move to different positions based on an on/off state of the driver, to switch between different braking modes. 
     In an implementation, the motion control component includes: a cylindrical body, extending along a first central axis and coupled to the output shaft of the driver; a protrusion portion, extending away from the cylindrical body from a surface of the cylindrical body, where the protrusion portion is configured to: abut against the first stopper portion in response to a case in which the driver is powered on, and abut against the second stopper portion in response to a case in which the driver is not powered on; a coupling shaft, extending along a second central axis from one end that is of the cylindrical body and that is close to the protrusion portion, where the second central axis deviates from and is parallel to the first central axis; and a drive ring, sleeved on the coupling shaft and coupled to the braking mode selection component. In such an arrangement, the motion control component may reliably switch between braking modes. 
     In an implementation, when the braking mode selection component is in the first position or the second position, a vertical connecting line between the first central axis and the second central axis is parallel to a first direction pointing from the first position to the second position. In such an arrangement, the driver may be prevented from being subject to a reverse acting force of the braking mode selection component, to prevent the driver from overheating. 
     In an implementation, the braking mode switching apparatus further includes an elastic member, coupled to the cylindrical body of the motion control component, and configured to reset the cylindrical body when the driver is not powered on, so that the braking mode selection component moves to the second position. In such an arrangement, when the driver cannot operate normally due to a failure, the elastic member performs a reset action, so that the braking mode selection component can automatically switch between braking modes without a need to perform a manual operation. 
     In an implementation, the braking mode switching apparatus further includes a housing. The housing includes a limiting plate, and the limiting plate is provided with a groove for accommodating the braking mode selection component, to limit the braking mode selection component, so that the braking mode selection component moves along a first direction pointing from the first position to the second position. In such an arrangement, movement of the braking mode selection component may be effectively limited. 
     In an implementation, the first transmission portion includes a first toothed portion, the first execution portion includes a second toothed portion that is configured to engage with the first toothed portion, and the first toothed portion engages with the second toothed portion when the driver is powered on. In such an arrangement, transmission between the first transmission portion and the first execution portion may be implemented in a reliable and cost-controllable manner. 
     In an implementation, the second transmission portion includes a third toothed portion, the second execution portion includes a fourth toothed portion that is configured to engage with the third toothed portion, and the third toothed portion engages with the fourth toothed portion when the driver is not powered on. In such an arrangement, transmission between the second transmission portion and the second execution portion may be implemented in a reliable and cost-controllable manner. 
     According to a second aspect, a brake control system for a vehicle is provided. The brake control system includes the braking mode switching apparatus according to the first aspect and a brake pedal. The brake pedal is coupled to a transmission member by using a connecting rod. In such an arrangement, switching of a braking mode of the brake control system for a vehicle can be implemented without a need to perform an additional operation. 
     In an implementation, the brake control system further includes a feedback assembly coupled to a first execution portion of the braking mode switching apparatus, and the feedback assembly is configured to provide a reverse acting force to the brake pedal when a driver is powered on. In such an arrangement, a driver may obtain more natural driving experience. 
     In an implementation, the brake control system further includes a brake cable coupled to a second execution portion of the braking mode switching apparatus, and the brake cable is configured to brake the vehicle when a driver is not powered on. In such an arrangement, safe driving of the vehicle may be ensured when an electrical system of the vehicle is faulty. 
     Descriptions of the plurality of embodiments appear below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing features, advantages and aspects and other features, advantages, and aspects of the embodiments become clearer with reference to the accompanying drawings and the following detailed descriptions. In the accompanying drawings, same or similar reference numerals represent same or similar elements. The accompanying drawings are not necessarily drawn in proportion. 
         FIG.  1    is a three-dimensional schematic diagram showing a braking mode switching apparatus according to an embodiment; 
         FIG.  2    is a schematic exploded view that shows a braking mode switching apparatus shown in  FIG.  1    and that exists when the braking mode switching apparatus is viewed from a first perspective; 
         FIG.  3    is a schematic exploded view that shows a braking mode switching apparatus shown in  FIG.  1    and that exists when the braking mode switching apparatus is viewed from a second first perspective, where some components are omitted; and 
         FIG.  4    is an enlarged schematic diagram showing a detail of a portion A in  FIG.  3   . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The following describes embodiments in more detail with reference to accompanying drawings. Although some embodiments are shown in the accompanying drawings, it should be understood that the embodiments may be implemented in various forms and should not be construed to be limited to the embodiments described herein. It should be understood that the accompanying drawings and the embodiments are merely used as examples but are not used to limit the scope of the embodiments. 
     In descriptions of the embodiments, the term “including” and similar terms should be understood as non-exclusive inclusion, namely, “including but not limited to.” The term “based on” should be understood as “based on at least a part of”. The term “one embodiment” or “this embodiment” should be understood as “at least one embodiment”. The terms “first”, “second”, and the like may refer to different or same objects. Other explicit and implied definitions may be further included below. 
     The following describes some implementations of a brake control system according to the embodiments with reference to a use scenario of a vehicle. The term “vehicle” may include various forms. For example, the vehicle may be an electric vehicle, a fuel vehicle, or a hybrid vehicle. In some embodiments, the vehicle may be a household vehicle, a passenger vehicle of an operational nature, a freight vehicle of an operational nature, or the like. In some embodiments, the vehicle may be a vehicle equipped with an autonomous driving capability, the autonomous driving capability may include but is not limited to an assisted driving capability, a semi-autonomous driving capability, a highly automated driving capability, or a fully automated driving capability. A form of the vehicle is not limited by the forms listed above, provided that a braking operation needs to be performed for the vehicle. 
     The following describes more details of the embodiments with reference to  FIG.  1    to  FIG.  4   .  FIG.  1    is an overall three-dimensional schematic diagram of a braking mode switching apparatus  1  in a brake control system  2  for a vehicle according to an embodiment. The braking mode switching apparatus  1  is configured to switch a braking mode of the vehicle. 
     The following describes the braking mode of the vehicle. Currently, many vehicles are braked by using an electromechanical brake (EMB) system. When an electrical system of the vehicle runs normally, the EMB system may sense that a brake pedal is depressed, and control, in an electrical manner, a brake pad to tightly hold a tire of the vehicle, so as to generate a braking force to implement braking. In the embodiments, this mode is referred to as a “first braking mode”. The EMB system needs to depend on the electrical system of the vehicle to provide a power support. Therefore, once the electrical system fails, the EMB system cannot operate normally. In this case, a mechanical drive system needs to be used to perform braking. In the embodiments, this mode is referred to as a “second braking mode”. 
     As shown in  FIG.  1   , the braking mode switching apparatus  1  is coupled to a connecting rod  33 . The brake pedal (not shown) may be connected to a side of the connecting rod  33 . The brake pedal may be coupled to a connecting hole  37  located on a side of the connecting rod  33  and rotate around an axis C of the connecting rod  33 . When the brake pedal is depressed, a braking action may be transmitted to an inside of the braking mode switching apparatus  1  through the connecting rod  33 , and the braking mode switching apparatus  1  may switch the braking mode of the vehicle between the first braking mode and the second braking mode based on a state of the electrical system of the vehicle. This is described in more detail below with reference to an internal structure of the braking mode switching apparatus  1 . 
     More details of the braking mode switching apparatus  1  are described below with reference to  FIG.  2    to  FIG.  4   . As shown in  FIG.  2   , the braking mode switching apparatus  1  generally includes a braking mode selection component  20 , a transmission member  30 , a stopper  10 , a driver  70 , and a motion control component  40 . The braking mode selection component  20  can move between a first position and a second position along a first direction L 1 , the first position corresponds to the first braking mode, the second position corresponds to the second braking mode, and the first direction L 1  is a direction pointing from the first position to the second position. The transmission member  30  is coupled to the braking mode selection component  20  and includes a first transmission portion  31  and a second transmission portion  32 . With reference to  FIG.  2    and  FIG.  3   , in an illustrated embodiment, a groove  24  may be disposed on a side that is of the braking mode selection component  20  and that faces the transmission member  30 , a protrusion  34  may be disposed on a side that is of the transmission member  30  and that faces the braking mode selection component  20 , and at least a part of the protrusion  34  may be accommodated in the groove  24 , so that the braking mode selection component  20  is coupled to the transmission member  30 . In such an arrangement, when the braking mode selection component  20  moves between the first position and the second position along the first direction L 1 , the transmission member  30  may be driven to move along the first direction L 1 . 
     As shown in  FIG.  3   , the stopper  10  includes a first stopper portion  11  and a second stopper portion  12 , to limit movement of the motion control component  40 . In the illustrated embodiment, the stopper  10  includes a C-shaped physical structure, and the first stopper portion  11  and the second stopper portion  12  may be two ends of the physical structure and may be used to limit the motion control component  40  to a moving range. For example, as shown in  FIG.  3   , the moving range may be 180°, the first stopper portion  11  is a lower limiting position, and the second stopper portion  12  is an upper limiting position. In another embodiment, the moving range may be any angle that is approximately between 150° and 210°. In a further embodiment, the moving range may be larger or smaller, and this aspect is not strictly limited. 
     In some embodiments, the stopper  10  may be directly or indirectly mounted on a frame of the vehicle. It should be understood that a form of the stopper  10  described herein is merely an example but imposes no limitation. In a scenario, a structure of the stopper  10  and a corresponding travel range may be correspondingly adjusted based on an actual requirement of driving. 
     As shown in  FIG.  3   , the driver  70  may include an output shaft  72 . The output shaft  72  is coupled to the motion control component  40 , so that the motion control component  40  can rotate with the output shaft  72 . The motion control component  40  is coupled to the braking mode selection component  20 . If the driver  70  is powered on, the motion control component  40  abuts against the first stopper portion  11 , and the braking mode selection component  20  is located in the first position, so that the transmission member  30  moves downward, and the first transmission portion  31  of the transmission member  30  engages with a first execution portion  80 . The first execution portion  80  is located outside the braking mode switching apparatus  1  and is stationary in the first direction L 1 . If the driver  70  is not powered on, the motion control component  40  abuts against the second stopper portion  12 , and the braking mode selection component  20  is located in the second position, so that the transmission member  30  moves upward, and the second transmission portion  32  of the transmission member  30  engages with a second execution portion  90 . The second execution portion  90  is located outside the braking mode switching apparatus  1  and is also stationary in the first direction L 1 . Based on whether the driver  70  is powered on, a moving direction of the transmission member  30  may be changed, and the braking mode switching apparatus  1  engages with either of the first execution portion  80  and the second execution portion  90 , to switch between different braking modes. 
     As shown in  FIG.  4   , the motion control component  40  may include a cylindrical body  42 . The cylindrical body  42  extends around a first central axis A 1 . With reference to  FIG.  2   , the cylindrical body  42  includes an annular groove  41  that faces and accommodates the output shaft  72  of the driver  70 , so that the cylindrical body  42  is coupled to the output shaft  72  of the driver  70 . 
     The motion control component  40  is provided with a protrusion portion  44  that extends away from the cylindrical body  42  from a surface of the cylindrical body  42 . When the driver  70  is powered on, the output shaft  72  is used to drive the motion control component  40  to rotate, so that the protrusion portion  44  of the motion control component  40  abuts against the first stopper portion  11 . When the driver  70  is not powered on, the output shaft  72  is used to drive the motion control component  40  to rotate, so that the protrusion portion  44  of the motion control component  40  abuts against the second stopper portion  12 . The motion control component  40  further includes a coupling shaft  46  that extends from one end of the cylindrical body  42  and includes a drive ring  48  disposed on the coupling shaft  46 . As shown in  FIG.  4   , the coupling shaft  46  and the protrusion portion  44  are located on a same side of the first central axis A 1 . The coupling shaft  46  extends approximately along a second central axis A 2 . As shown in  FIG.  4   , the second central axis A 2  is parallel to the first central axis A 1 , and deviates from the first central axis A 1 . 
     The drive ring  48  is coupled to the braking mode selection component  20 . This is best shown in  FIG.  2   . In the illustrated embodiment, a receiving portion  22  is disposed on a side that is of the braking mode selection component  20  and that faces the drive ring  48 , and the receiving portion  22  is configured to receive the drive ring  48 , so that when the drive ring  48  moves with the coupling shaft  46 , the braking mode selection component  20  can be driven to move. 
     The following describes the first braking mode in this embodiment with reference to a schematic scenario. In some embodiments, the driver  70  may be a motor on the vehicle. Provided that the electrical system of the vehicle runs normally, the driver  70  may be powered on. In this case, the driver  70  may rotate along a first rotation direction C 1  shown in  FIG.  3   , so that the output shaft  72  is used to drive the motion control component  40  to rotate in the first rotation direction C 1 . In this case, the protrusion portion  44  of the motion control component  40  rotates to a position abutting against the first stopper portion  11 . Because the coupling shaft  46  and the protrusion portion  44  are located on a same side of the first central axis A 1 , currently, the coupling shaft  46  moves to a lower limiting position of the coupling shaft  46 , and the drive ring  48  is also located in a lower limiting position of the drive ring  48 , to drive the braking mode selection component  20  and the transmission member  30  to move downward. In this case, referring to  FIG.  2    and  FIG.  3   , the first transmission portion  31  of the transmission member  30  engages with the first execution portion  80 . 
     In some embodiments, the brake control system  2  of the vehicle may include a feedback assembly  82  that is coupled to the first execution portion  80 . In a further embodiment, the feedback assembly  82  may be a spring or a spring group, the spring or the spring group extend along a direction of an axis of the feedback assembly  82 , to provide a reverse acting force to the brake pedal when the driver  70  is powered on. In such an arrangement, when the electrical system of the vehicle operates normally, and a driver depresses the brake pedal, a proper braking feedback may be obtained. Based on the feedback, the driver may learn that the state of the electrical system of the vehicle is normal. 
     In some embodiments, as shown in  FIG.  2   , the braking mode switching apparatus  1  may further include a barrel  86 , configured to mount and accommodate the feedback assembly  82 . The barrel  86  may be directly or indirectly fastened to the frame of the vehicle, to ensure that the feedback assembly  82  moves only along the axis the feedback assembly  82  in response to a case in which the brake pedal is depressed. 
     The following describes the second braking mode in this embodiment with reference to a schematic scenario. In some embodiments, the braking mode switching apparatus  1  further includes an elastic member  60  coupled to the cylindrical body  42  of the motion control component  40 . As shown in  FIG.  4   , the elastic member  60  may be in a form of a torsion spring. As shown in  FIG.  3   , once the electrical system on the vehicle fails, power provided to the driver  70  also fails. In this case, the driver  70  is powered on. Under a reset action of the elastic member  60 , the cylindrical body  42  of the motion control component  40  rotates along a second rotation direction C 2  shown in  FIG.  3   . In this case, the protrusion portion  44  of the motion control component  40  rotates to a position abutting against the second stopper portion  12 , namely, the upper limiting position shown in the figure. Because the coupling shaft  46  and the protrusion portion  44  are located on a same side of the first central axis A 1 , currently, the coupling shaft  46  moves to the upper limiting position of the coupling shaft  46 , and the drive ring  48  is also located in the upper limiting position of the drive ring  48 , to drive the braking mode selection component  20  and the transmission member  30  to move upward. In this case, referring to  FIG.  2    and  FIG.  3   , the second transmission portion  32  of the transmission member  30  engages with the second execution portion  90 . 
     In some embodiments, the brake control system  2  of the vehicle may include a brake cable  92  that is coupled to the second execution portion  90 , and the brake cable  92  is configured to mechanically brake the vehicle when the driver  70  is not powered on. As shown in  FIG.  2   , the brake cable  92  may be connected to the second execution portion  90  by using a guide arm  96 . The brake cable  92  may be connected to a series of mechanical transmission assemblies (not shown), and the vehicle may be braked by using the brake cable  92  in various transmission manners that are known or to be developed in the future and are not limited in this embodiment. In such an arrangement, if the electrical system of the vehicle cannot operate normally, when the driver depresses the brake pedal, the connecting rod  33  pushes the transmission member  30  to drive the second execution portion  90  to move, to perform a braking action on the brake cable  92  by using the guide arm  96 , and ensure that the vehicle can be braked in a case of an electrical failure and parked for maintenance if necessary, so as to improve driving safety. 
     In some embodiments, as shown in  FIG.  2   , the braking mode switching apparatus  1  may further include a rebound spring  98  that is coupled to the guide arm  96 . The rebound spring  98  may be in the form of the torsion spring as shown in the figure. After depressing of the brake pedal is released, the rebound spring  98  may perform a reset action of the rebound spring  98 , so that the brake cable  92  returns to an original position, to repeat the foregoing motion next time the brake pedal is depressed. 
     According to the brake control system in this embodiment, when an electrical device of the vehicle fails, the braking mode may be automatically switched, so that without a need to perform an addition operation by a driver, it is ensured that braking performance of the vehicle is not affected. 
     In some embodiments, as shown in  FIG.  2   , the braking mode switching apparatus  1  further includes a housing  50 . The housing  50  may be directly or indirectly mounted on the frame of the vehicle, so that the housing  50  is stationary relative to the vehicle. The housing  50  may include a limiting plate  52 , and the limiting plate  52  is provided with a groove  54 , configured to accommodate the braking mode selection component  20 , to limit the braking mode selection component  20 , so that the braking mode selection component  20  moves along the first direction L 1 . 
     In some embodiments, when the braking mode selection component  20  is located in the first position or the second position, in other words, when the protrusion portion  44  of the motion control component  40  is in an upper limiting position and a lower limiting position of the protrusion portion  44 , a vertical connecting line between the first central axis A 1  and the second central axis A 2  is parallel to the first direction L 1 . 
     As discussed above, the braking mode selection component  20  is built in the groove  54  of the limiting plate  52  of the housing  50 . Therefore, the braking mode selection component  20  can move only along the first direction L 1  shown in  FIG.  2    to  FIG.  4   . Because the drive ring  48  is built in the receiving portion  22  of the braking mode selection component  20 , an acting force that is exerted by the output shaft  72  of the driver  70  on the drive ring  48  is parallel to the first direction L 1 . In this case, regardless of whether the motion control component  40  is located in the upper limiting position shown in  FIG.  4    or located in the lower limiting position opposite to the upper limiting position, because the vertical connecting line between the first central axis A 1  of the motion control component  40  and the second central axis A 2  of the drive ring  48  is parallel to the first direction L 1 , a torque is not generated for the acting force to disengage the protrusion portion  44  of the motion control component  40  from the upper limiting position or the lower limiting position. In other words, the motion control component  40  is “self-locked” in the upper limiting position or the lower limiting position of the motion control component  40 , and only under an action of the driver  70  serving as a driving apparatus, the output shaft  72  is used to drive the motion control component  40  to be disengaged from the upper limiting position or the lower limiting position, while when the braking mode selection component  20  serving as a driven apparatus moves, the motion control component  40  is not disengaged from the upper limiting position or the lower limiting position. Based on the mechanical self-locking principle, a too large reverse acting force exerted by the braking mode selection component  20  on the driver  70  may be avoided, to avoid a heat generation problem of the driver  70  due to the too large reverse acting force. 
     In some embodiments, as shown in  FIG.  2    and  FIG.  3   , the first transmission portion  31  may include a first toothed portion  35 , and the first execution portion  80  includes a second toothed portion  84  that matches the first toothed portion  35 . As shown in the figure, the first toothed portion  35  and the second toothed portion  84  may be in a form of a gear rack. In such an arrangement, a motion of the transmission member  30  may be stably and reliably transmitted to the first execution portion  80 . 
     In some embodiments, as shown in  FIG.  2    and  FIG.  3   , the second transmission portion  32  may include a third toothed portion  36 , and the second execution portion  90  includes a fourth toothed portion  94  that matches the third toothed portion  36 . As shown in the figure, the third toothed portion  36  and the fourth toothed portion  94  may be in a form of a gear rack. In such an arrangement, the motion of the transmission member  30  may be stably and reliably transmitted to the second execution portion  90 . 
     In comparison with a conventional solution, the brake control system in the embodiments may automatically switch the braking mode when the electrical device of the vehicle fails, to avoid a traffic accident that occurs due to low braking performance In addition, an overheating problem of the motor of the vehicle may also be overcome, to produce a good use effect. 
     Although is the embodiments are described with structural features and/or methodological actions, it should be understood that the embodiments are not limited to the features or actions described. On the contrary, the features and actions described above are merely example forms of embodiments and are non-limiting.