Patent Publication Number: US-11377129-B2

Title: Traction mechanism, bogie assembly, and straddle-type monorail vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a national phase application of International Application No. PCT/CN2017/075172, filed on Feb. 28, 2017, which is based on and claims priority to and benefits of Chinese Patent Application No. 201610839645.3, filed with the State Intellectual Property Office (SIPO) of the People&#39;s Republic China on Sep. 21, 2016. The entire contents of the above-identified applications are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure belongs to the technical field of vehicle manufacture, and in particular to, a traction mechanism, a bogie assembly having the traction mechanism, and a straddle-type monorail vehicle having the bogie assembly. 
     BACKGROUND 
     The cost of laying a straddle-type monorail transit system is much lower than that of a subway transit system, and the straddle-type monorail transit system has a wider range of applications. A traction mechanism between a vehicle body and a bogie frame is an important transmission component of a straddle-type monorail vehicle, and its performance directly affects the safety and ride comfort of the straddle-type monorail vehicle. In the related art, the traction connection between a bogie and the vehicle body is mainly realized by a central traction pin assembly. During the running, the power of a running wheel is transmitted to the bogie frame, and a traction force is transmitted to the vehicle body through the central traction pin assembly. However, the traction mechanism is only applicable to a double-axle bogie, and the pitch motion of the bogie cannot be suppressed. Since the structure is complicated, a large mounting space is occupied, and there is a need for improvement. 
     SUMMARY 
     The present disclosure solves one of technical problems in related technologies at least to a certain extent. In view of this, an objective of the present disclosure is to provide a traction mechanism having a wide range of applications. 
     Another objective of the present disclosure is to provide a bogie assembly having the foregoing traction mechanism. 
     Yet another objective of the present disclosure is to provide a straddle-type monorail vehicle having the foregoing bogie assembly. 
     A traction mechanism according to an embodiment of a first aspect of the present disclosure includes: a traction component, including a traction connecting rod, a first crank and a transmission shaft, the traction connecting rod being suitable to be hinged to a bogie frame, a first end of the first crank being hinged to the traction connecting rod, a second end of the first crank being fixedly connected to the transmission shaft, and the transmission shaft being suitable to be rotatably connected to a vehicle body; and a traction crank, both ends of the traction crank being suitable to be respectively hinged to the bogie frame and the vehicle body, wherein the first end of the first crank is away from the traction crank. 
     The traction mechanism according to the embodiment of the first aspect of the present disclosure has a simple and compact structure, a transmission path of a traction force is short, and the traction mechanism is convenient to assemble and disassemble, occupies a small space, is wide in usage range, can be used for low-floor and high-floor vehicles, and is also applicable to a single-axle bogie, a double-axle bogie and a multi-axle bogie. 
     In addition, the traction mechanism according to the foregoing embodiment of the present disclosure may also have the following additional technical features: 
     In some embodiments of the present disclosure, there are at least two traction components which are spaced apart laterally. 
     In some embodiments of the present disclosure, a projection of the traction crank in a horizontal plane is located between projections of the at least two traction components in the horizontal plane. 
     Optionally, there are two traction components, each traction component further includes a second crank, and a first end of the second crank is fixedly connected to the transmission shaft, wherein the first end of the second crank is away from the bogie frame, and the traction mechanism further includes: a lateral connecting rod, both ends of the lateral connecting rod being respectively hinged to second ends of the two second cranks of the two traction components. 
     Optionally, the first crank and the second crank are arranged perpendicularly, and the first crank is located below the second crank. 
     Optionally, the first end of the second crank and the second end of the first crank are respectively connected to both ends of the transmission shaft through splines. 
     Optionally, the lateral connecting rod is set to be adjustable in length. 
     Further, the lateral connecting rod includes: a lateral connecting rod thread sleeve with two internal thread segments that screw in opposite directions; and two sub-lateral connecting rods, one end of each sub-lateral connecting rod being in threaded connection with one thread segment of the lateral connecting rod thread sleeve, and the other end of each sub-lateral connecting rod including a hinging joint. 
     In some embodiments of the present disclosure, the traction connecting rod is set to be adjustable in length. 
     Optionally, the traction connecting rod includes: a traction connecting rod thread sleeve with two internal thread segments that screw in opposite directions; and two sub-traction connecting rods, one end of each sub-traction connecting rod being in threaded connection with one thread segment of the traction connecting rod thread sleeve, and the other end of each sub-traction connecting rod including a hinging joint. 
     In some embodiments of the present disclosure, the transmission shaft is sleeved with a transmission shaft vehicle body connecting base, suitable to be connected to the vehicle body. 
     Optionally, each transmission shaft is sleeved with a plurality of transmission shaft vehicle body connecting bases, spaced apart in an up-down direction. 
     In some embodiments of the present disclosure, the traction mechanism further includes: a crank vehicle body connecting base, suitable to be connected to the vehicle body, and hinged to the first end of the traction crank; and a crank bogie connecting base, suitable to be connected to the bogie frame, and hinged to the second end of the traction crank. 
     Optionally, the first end of the traction crank includes a damping bushing. 
     In some embodiments of the present disclosure, both the traction connecting rod and the traction crank are spherically hinged to the bogie frame. 
     A bogie assembly according to an embodiment of a second aspect of the present disclosure includes the traction mechanism according to any of the contents involved in the first aspect. 
     The bogie assembly has the same advantages as the foregoing traction mechanism with respect to the prior art, and details are not described herein again. 
     A straddle-type monorail vehicle according to an embodiment of a third aspect of the present disclosure includes the bogie assembly according to any of the contents involved in the second aspect. 
     The straddle-type monorail vehicle has the same advantages as the foregoing bogie assembly with respect to the prior art, and details are not described herein again. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing and/or additional aspects and advantages of the present disclosure become obvious and easily understood in descriptions of the embodiments with reference to the following accompanying drawings. 
         FIG. 1  is a structural schematic view of a bogie assembly according to an embodiment of the present disclosure; 
         FIG. 2  is a side view of a bogie assembly according to an embodiment of the present disclosure; 
         FIG. 3  is a structural schematic view of a traction mechanism according to an embodiment of the present disclosure; 
         FIG. 4  is a structural schematic view of a partial structure of a traction component according to an embodiment of the present disclosure; and 
         FIG. 5  is a structural schematic view of a traction connecting rod and a lateral connecting rod according to an embodiment of the present disclosure. 
     
    
    
     Drawing reference numerals: 
     bogie assembly  1000 , 
     bogie frame  100 , 
     traction mechanism  200 , 
     traction component  210 , traction connecting rod  211 , sub-traction connecting rod  211   a , traction connecting rod thread sleeve  211   b , first crank  212 , transmission shaft  213 , second crank  214 , lateral connecting rod  215 , sub-lateral connecting rod  215   a , lateral connecting rod thread sleeve  215   b,    
     traction crank  220 , damping bushing  221 , 
     transmission shaft vehicle body connecting base  231 , crank vehicle body connecting base  232 , crank bogie connecting base  233 , 
     running wheel  300 , guide wheel  400 , stabilizing wheel  500 . 
     DETAILED DESCRIPTION 
     The following describes embodiments of the present disclosure in detail. Examples of the embodiments are shown in the accompanying drawings, where reference numerals that are the same or similar from beginning to end represent same or similar components or components that have same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary, and are used for explaining rather than limiting the present disclosure. 
     In the descriptions of this specification, descriptions such as reference terms “an embodiment”, “some embodiments”, “example”, “specific example”, or “some examples” intend to indicate that specific features, structures, materials, or characteristics described with reference to embodiments or examples are included in at least one embodiment or example of the present disclosure. In this specification, schematic descriptions of the foregoing terms do not need to direct at a same embodiment or example. Besides, the specific features, the structures, the materials or the characteristics that are described may be combined in a proper manner in any one or more embodiments or examples. In addition, in a case that is not mutually contradictory, persons skilled in the art can combine or group different embodiments or examples that are described in this specification and features of the different embodiments or examples. 
     The present disclosure is described in detail below with reference to the accompanying drawings and the embodiments. 
     A bogie assembly  1000  according to an embodiment of the present disclosure is described in detail with reference to the accompanying drawings. As shown in  FIG. 1  to  FIG. 2 , the bogie assembly  1000  includes a bogie frame  100 , a traction mechanism  200 , a running wheel  300 , a guide wheel  400 , and a stabilizing wheel  500 . 
     The bogie frame  100  may have a rail recess for straddling a rail beam, the running wheel  300 , the guide wheel  400  and the stabilizing wheel  500  are all mounted on the bogie frame  100 , and the traction mechanism  200  is connected between the bogie frame  100  and a vehicle body of a straddle-type monorail vehicle. When the running wheel  300  rotates along a rail, power for driving the straddle-type monorail vehicle to move is transmitted to the bogie frame  100 , and the bogie frame  100  transmits a traction force to the vehicle body through the traction mechanism  200 . 
     The traction mechanism  200  according to an embodiment of the present disclosure is described below with reference to  FIG. 1  to  FIG. 5 . As shown in  FIG. 1  to  FIG. 3 , the traction mechanism  200  includes a traction component  210  and a traction crank  220 . 
     The traction component  210  is suitable to be rotatably connected to the vehicle body, and a traction connecting rod  211  of the traction component  210  is suitable to be hinged to the bogie frame  100 . Optionally, referring to  FIG. 3 , the traction component  210  may further include a first crank  212  and a transmission shaft  213 , an end (first end) of the first crank  212  away from the traction crank  220  may be hinged to the traction connecting rod  211 , and an end (second end) of the first crank  212  close to the traction crank  220  may be fixedly connected to the transmission shaft  213 . For example, the second end of the first crank  212  may be connected to a lower end of the transmission shaft  213  through a spline. 
     The transmission shaft  213  is suitable to be rotatably connected to the vehicle body. For example, the transmission shaft  213  may be sleeved with a transmission shaft vehicle body connecting base  231 , the transmission shaft vehicle body connecting base  231  being suitable to be connected to the vehicle body. Referring to  FIG. 3  and  FIG. 4 , the transmission shaft vehicle body connecting base  231  may include a plurality of mounting holes, and the transmission shaft vehicle body connecting base  231  may be connected to the vehicle body through a threaded fastener passing through the mounting hole. Each transmission shaft  213  may be sleeved with a plurality of transmission shaft vehicle body connecting bases  231  spaced apart in an up-down direction (Z direction). For example, each transmission shaft  213  in  FIG. 3  and  FIG. 4  may correspond to two transmission shaft vehicle body connecting bases  231 . 
     A first end of the traction crank  220  is suitable to be hinged to the vehicle body, and a second end of the traction crank  220  is suitable to be hinged to the bogie frame  100 . Referring to  FIG. 3 , the traction mechanism  200  may further include a crank vehicle body connecting base  232  and a crank bogie connecting base  233 , the crank vehicle body connecting base  232  is suitable to be connected to the vehicle body, and the crank bogie connecting base  233  is suitable to be connected to the bogie frame  100 . The crank vehicle body connecting base  232  may be fixedly connected to the vehicle body through a threaded fastener, the crank bogie connecting base  233  may be fixedly connected to the bogie frame  100  through a threaded fastener, or the crank bogie connecting base  233  may be welded to the bogie frame  100 . The crank vehicle body connecting base  232  is hinged to the first end of the traction crank  220 , and the crank bogie connecting base  233  is hinged to the second end of the traction crank  220 . The first end of the traction crank  220  may include a damping bushing  221 . In this way, the vibration shock of an X direction (an extending direction of the rail beam) can be buffered, and the ride comfort can be improved. The damping bushing  221  may be a rubber sleeve or a nylon sleeve. 
     Optionally, both the traction connecting rod  211  and the traction crank  220  are spherically hinged to the bogie frame  100 . In this way, when the load on the vehicle body changes, the vehicle body may be relatively raised or lowered. For example, when there are many passengers in the vehicle body, the traction connecting rod  211  may rotate downward around a spherical hinging joint between the traction connecting rod  211  and the bogie frame  100 , and the traction crank  220  may rotate downward around a spherical hinging joint between the traction crank  220  and the bogie frame  100 , so that the entire vehicle body is settled downward, and the center of gravity is lowered. 
     The traction force transmission path of the traction mechanism  200  according to the embodiment of the present disclosure is: a portion of a traction force is transmitted through the traction component  210 , where the traction force is transmitted from the bogie frame  100  to the traction connecting rod  211 , then transmitted to the transmission shaft  213  through the first crank  212 , and finally transmitted to the vehicle body through the transmission shaft vehicle body connecting base  231 ; another portion of the traction force is transmitted through the traction crank  220 , where the traction force is transmitted from the bogie frame  100  to the crank bogie connecting base  233 , then transmitted to the crank vehicle body connecting base  232  through the traction crank  220 , and finally transmitted to the vehicle body. 
     When the straddle-type monorail vehicle turns, the traction connecting rod  211  rotates relative to the bogie, the first crank  212  rotates together with the transmission shaft  213  relative to the traction connecting rod  211 , the transmission shaft vehicle body connecting base  231  rotates relative to the transmission shaft  213 , and the traction crank  220  rotates relative to the crank bogie connecting base  233  and the crank vehicle body connecting base  232 . 
     The traction mechanism  200  according to the embodiment of the present disclosure has a simple and compact structure, a transmission path of a traction force is short, the traction mechanism  200  is convenient to assemble and disassemble and occupies a small space, and the traction mechanism  200  is wide in usage range, can be used for low-floor and high-floor vehicles, and is also applicable to a single-axle bogie, a double-axle bogie and a multi-axle bogie. 
     A bogie assembly  1000  according to an embodiment of the present disclosure includes the traction mechanism  200  in the foregoing structural form, so that the bogie assembly  1000  has a simple and compact structure, is convenient to assemble and disassemble, and is efficient in power transmission. 
     The traction mechanism  200  according to some embodiments of the present disclosure is described below. 
     In some embodiments of the present disclosure, there are at least two traction components  210 . Referring to  FIG. 1  and  FIG. 3 , two traction components  210  may be spaced apart in a lateral direction (Y direction, left-right direction), and a projection of the traction crank  220  in a horizontal plane may be located between projections of the two traction components  210  in the horizontal plane. Optionally, the traction crank  220  is equally spaced apart from the two traction connecting rods  211 , the two traction connecting rods  211  have an equal height in an up-down direction, and the traction crank  220  may be located above the two traction connecting rods  211 . 
     Thus, the traction mechanism  200  according to the embodiment of the present disclosure forms a three-connecting rod mechanism, and the traction crank  220  and the two traction connecting rods  211  form a stable three-point traction. The traction stability is strong, so that the traction mechanism  200  has sufficient anti-roll capability. 
     In some embodiments of the present disclosure, the traction mechanism  200  may further include a lateral connecting rod  215 , and there are at least two traction components  210 . Referring to  FIG. 1  and  FIG. 3 , each traction component  210  includes a traction connecting rod  211 , a first crank  212 , a transmission shaft  213 , and a second crank  214 . A first end of the traction connecting rod  211  is hinged to the bogie frame  100 , a second end of the traction connecting rod  211  is hinged to a first end of the first crank  212 , a second end of the first crank  212  may be fixedly connected to a lower end of the transmission shaft  213 , the transmission shaft  213  is rotatably connected to the vehicle body, an upper end of the transmission shaft  213  may be fixedly connected to an end (first end) of the second crank  214  away from the bogie frame, and both ends of the lateral connecting rod  215  are respectively hinged to ends (second ends) of the two second cranks  214  close to the bogie frame  100 . 
     The first crank  212 , the transmission shaft  213  and the second crank  214  do not rotate relative to each other. For example, the second crank  214  is connected to the upper end of the transmission shaft  213  through a spline, and the first crank  212  is connected to the lower end of the transmission shaft  213  through a spline. Throughout the operation of the traction mechanism  200 , the axis of the second crank  214  and the axis of the first crank  212  remain unchanged. Optionally, the second crank  214  and the first crank  212  are arranged perpendicularly. In other words, the length direction of the second crank  214  is perpendicular to the length direction of the first crank  212 , so that the arm of force of the traction component  210  is longer, and the force transmission is efficient. Of course, other manners such as a form of key grooves may be adopted to fixedly connect the first crank  212  and the transmission shaft  213  as well as the second crank  214  and the transmission shaft  213 . Optionally, the first crank  212  is located below the second crank  214 . 
     It is understandable that when turning, the interaction of the lateral connecting rod  215  and the two traction components  210  can ensure that the two traction connecting rods  211  are deflected in the same direction, so that the vehicle body can smoothly pass through a small curve. Further, when the straddle-type monorail vehicle enters a curve, clamping forces of guide wheels  400  on both sides of the rail beam are different, and the traction component  210  on the side where the clamping force is relatively large may transmit the force to the traction component  210  on the other side through the lateral connecting rod  215 , thereby balancing the clamping forces of the guide wheels  400  on both sides. 
     In the case of emergency braking or rapid acceleration, the bogie frame  100  has a tendency to skew forward or backward about a wheel axle due to inertia, and the traction mechanism  200  formed by the lateral connecting rod  215 , the traction component  210  and the traction crank  220  can effectively constrain the pitch motion of the bogie frame  100 . 
     That is to say, the traction mechanism  200  according to the embodiment of the present disclosure has a function of assisting steering and suppressing the pitch motion of the bogie frame  100 . 
     In some embodiments of the present disclosure, referring to  FIG. 5 , the traction connecting rod  211  may be set to be adjustable in length. Optionally, the traction connecting rod  211  may include a traction connecting rod thread sleeve  211   b  and two sub-traction connecting rods  211   a . The traction connecting rod thread sleeve  211   b  may include two internal thread segments that screw in opposite directions, one end of each sub-traction connecting rod  211   a  is in threaded connection with one thread segment of the traction connecting rod thread sleeve  211   b , and the traction connecting rod  211  can be conveniently extended and/or retracted by rotating the traction connecting rod thread sleeve  211   b . The other end of each sub-traction connecting rod  211   a  includes a hinging joint. The hinging joint of one of the sub-traction connecting rods  211   a  is used for hinging to the bogie frame  100 , where the hinging joint may be a universal spherical hinge. The hinging joint of the other sub-traction connecting rod  211   a  is used for hinging to the first crank  212 . 
     In some embodiments of the present disclosure, referring to  FIG. 5 , the lateral connecting rod  215  may be set to be adjustable in length. Optionally, the lateral connecting rod  215  may include a lateral connecting rod thread sleeve  215   b  and two sub-lateral connecting rods  215   a . The lateral connecting rod thread sleeve  215   b  may include two internal thread segments that screw in opposite directions, one end of each sub-lateral connecting rod  215   a  is in threaded connection with one thread segment of the lateral connecting rod thread sleeve  215   b , and the lateral connecting rod  215  can be conveniently extended and/or retracted by rotating the lateral connecting rod thread sleeve  215   b . The other end of each sub-lateral connecting rod  215   a  includes a hinging joint. The two hinging joints of the two sub-lateral connecting rods  215   a  are respectively hinged to the two second cranks  214 . 
     The present disclosure also discloses a straddle-type monorail vehicle. The straddle-type monorail vehicle according to the embodiment of the present disclosure includes any bogie assembly  1000  described in the foregoing embodiment, which makes the straddle-type monorail vehicle efficient in power transmission and more convenient to assemble and disassemble. 
     In descriptions of the present disclosure, it is understandable that direction or position relationships indicated by terms such as “horizontal”, “length”, “width”, “thickness”, “above”, “below”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, and “axial” are direction or position relationships based on the accompanying drawings, and are used only for conveniently describing the present disclosure and simplifying descriptions, instead of indicating or suggesting that a represented apparatus or component needs to have a particular direction or is constructed and operated in a particular direction, and therefore shall not be understood as limiting the present disclosure. 
     In the present disclosure, it should be noted that unless otherwise clearly specified and limited, the terms “mounted”, “connected”, “connection”, and “fixed” should be understood in a broad sense. For example, a connection may be a fixed connection, a detachable connection, or an integral connection; may be a mechanical connection or an electrical connection; may be a direct connection or an indirect connection by means of an intermediate medium; or may be internal communication between two elements or interaction relationship between two elements, unless otherwise clearly limited. A person of ordinary skill in the art may understand specific meanings of the foregoing terms in the present disclosure according to a specific situation. 
     Although the embodiments of the present disclosure are shown and described above, it may be understood that the foregoing embodiments are examples, and cannot be understood as limitations to the present disclosure. A person of ordinary skill in the art may make changes, modifications, replacements, and variations to the foregoing embodiments without departing from the scope of the present disclosure.