Patent Publication Number: US-2016243912-A1

Title: Suspension arrangement

Description:
REFERENCE TO RELATED APPLICATIONS 
     The application is a continuation of U.S. patent application Ser. No. 14/218,397 filed on Mar. 18, 2014, which claims priority to United Kingdom Application No. 1304949.9 filed on Mar. 18, 2013. 
    
    
     TECHNICAL FIELD 
     The invention relates to the field of vehicles, such as passenger service vehicles. In particular, but not exclusively, the invention relates to suspension arrangements, or chassis and suspension arrangements, for such passenger service vehicles. Further, the invention relates to, but is not limited to, associated apparatus, structures, vehicles and methods. 
     BACKGROUND 
     There is a need for passenger service vehicles, such as coaches and buses, to have both good ride and good handling characteristics. However, achieving both can often lead to complex suspension arrangements, which can be costly and space prohibitive (i.e., the overall structure of the suspension arrangement may impede on the occupant or passenger space within the vehicle). Further, such complex systems may unhelpfully increase the overall weight of the vehicle. 
     As such, there is a continuing desire to provide suspension and chassis arrangements that are cost effective, can be installed in a limited space so as not to unduly restrict occupancy of the vehicle, or space within the vehicle, yet at the same time provide both good ride and handling characteristics, while at the same time minimizing the weight of the vehicle. 
     This background serves to set a scene to allow a skilled reader to better appreciate the following description. Therefore, none of the above discussion should necessarily be taken as an acknowledgement that that discussion is part of the state of the art or is common general knowledge. One or more aspects/embodiments of the invention may or may not address one or more of the background issues. 
     SUMMARY 
     According to a first aspect of the invention, there is provided a suspension arrangement for a passenger service vehicle. 
     The suspension arrangement may include one or more suspension mounts. The suspension mounts may be configured to attach an axle, such as a front axle, of a passenger service vehicle to a chassis. The suspension mounts may be configured to attach with a drop-beam axle. The suspension arrangement may include two suspension mounts, e.g., a left-hand mount and a right-hand mount. 
     The suspension mounts may be configured to mount with one or more of the following: suspension arm links, such as radius arms links, suspension air springs, suspension dampeners (e.g., telescoping dampeners), anti-roll bars, Panhard rods, or the like. The suspension arrangement may include one or more of the following: suspension arm links, such as radius arms links, suspension air springs, suspension dampeners (e.g., telescoping dampeners), anti-roll bars, Panhard rods, or the like, mounted with the chassis and the axle, using the suspension mount. 
     The suspension mounts may include one or more mounting apertures configured to allow for mounting (e.g., using bushes, bolts, or the like) of the arms links, air springs, etc. The mounting apertures may be preformed with the mount. 
     Each suspension mount may include a dished surface configured to allow mounting of an air spring. The dished surface may be angled from a body axis of the suspension mount. The angle may be between 90 and 100 degrees. The angle may be between 95 and 100 degrees. The angle may be 98 degrees. The suspension arrangement may be configured such that an air spring, or the like, is housed between the dished portion and a portion of the chassis. 
     Each suspension mount may include a body portion extending between the dished surface and an axle-mount portion. The body portion may include one or more curved ribs. The ribs may provide a rigid mount, while minimizing weight. The axle-mount portion may include one or more depending lugs. The lug or each lug may include mounting apertures. The suspension mount may be a unitary mount (e.g., from a single cast). 
     The suspension arrangement may additionally or alternatively include a suspension arrangement associated with the rear axle. The rear-axle can be considered the drive axle. One or more links, such as fixed links, may be used to attach the chassis to, for example, a rear differential. Such a rear differential may be configured to connect a drive shaft and the rear wheels. 
     The above mentioned configuration may allow for short rear overhangs with transverse mounted engines. 
     According to a further aspect of the invention, there is provided a passenger service vehicle. The vehicle may include one or more suspension arrangements having one or more of the features of the first aspect. 
     The vehicle may have an overall length of about 35 feet or less. For example, the vehicle may have an overall length of between 25 feet and 35 feet. In some examples, the vehicle may have an overall length of approximately 35 feet. Such a vehicle may be configured to provide at least 35 passenger seats. Such a vehicle may have an unladen weight of around 25,000 lbs or less (e.g., roughly 20,000 lbs or even less). 
     In other examples, the vehicle may have an overall length of approximately 30 feet. Such a vehicle may be configured to provide at least 27 passenger seats. Such a vehicle may have an unladen weight of around 22,000 lbs or less (e.g., 18,000 lbs or even less). 
     The vehicle may have a front overhang (i.e., the distance from the front of the vehicle to the center of a front axle) of around 250 cm, 230 cm or less (e.g., 226 cm). The vehicle may have a rear overhang (i.e., the distance from the rear of the vehicle to the center of a rear axle) of around 300 cm, 275 cm or less (e.g., 271 cm). 
     The vehicle may include a longitudinally mounted engine (e.g., a six cylinder longitudinally mounted engine). Such an engine may be compliant with, for example, environmental protection agency requirements. The vehicle may be a single-deck vehicle. The vehicle may include at least two passenger doors. The vehicle may include a vertical exit exhaust. The vehicle may include an air conditioning system. The conditions system may be mounted on the external of the vehicle. The conditioning system may be provided in a middle region of the vehicle. 
     The present invention includes one or more corresponding aspects, embodiments or features in isolation or in various combinations whether or not specifically stated (including claimed) in that combination or in isolation. It will be appreciated that one or more embodiments/aspects may be useful in providing suspension and chassis arrangements that are cost effective, can be installed in a limited space so as not to unduly restrict occupancy of the vehicle, or space within the vehicle, yet at the same time provide both good ride and handling characteristics. 
     The above summary is intended to be merely exemplary and non-limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A description is now given, by way of example only, with reference to the accompanying drawings in which: 
         FIG. 1  shows a side view of a passenger service vehicle; 
         FIGS. 2-3  show plan and side views of a passenger deck of the vehicle of  FIG. 1 ; 
         FIG. 4  shows a perspective view of a forward chassis and suspension apparatus of the vehicle, while  FIGS. 5-6  show front and plan views respectively; 
         FIG. 7  shows section A-A from  FIG. 6 ; 
         FIG. 8  shows section B-B from  FIG. 4 ; 
         FIG. 9  shows section C-C from  FIG. 6 ; 
         FIG. 10  shows section D-D from  FIG. 6 ; 
         FIG. 11  shows section E-E from  FIG. 6 ; 
         FIGS. 12-14  show views of a left-hand suspension mount; 
         FIGS. 15-17  show views of a right-hand suspension mount; 
         FIGS. 18-21  show various side and plan views of a rear suspension arrangement through various sections; and 
         FIGS. 22-23  show the associated drivelines for differing gearbox configurations. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a side view of a passenger service vehicle  100 . Here, the vehicle  100  may be considered to have an overall length of about 35 feet or less (i.e., a length from the front of the vehicle  100  to the rear of the vehicle  100  of 35 feet or less). 
     In some examples, the vehicle  100  has an overall length of approximately 35 feet. Such a vehicle  100  may be configured to provide at least 35 passenger seats. Such a vehicle may have an unladen weight of around 25,000 lbs or less (e.g., roughly 20,000 lbs or even less). In other examples, the vehicle  100  may have an overall length of approximately 30 feet. In those cases, the vehicle  100  may be configured to provide fewer seats, such as at least 24 passenger seats, or even 27 passenger seats. Such a vehicle  100  may have an unladen weight of around 22,000 lbs or less (e.g., around 18,000 lbs or even less). 
     As shown, the vehicle  100  has a front overhang (i.e., the distance from the front of the vehicle  100  to the center of a front axle  110 ). The front overhang can be considered to be around 230 cm or less (e.g., 226 cm). The vehicle  100  also has a rear overhang (i.e., the distance from the rear of the vehicle to the center of a rear axle  120 ). In this example, the rear overhang can be considered to be 275 cm or less (e.g., 271 cm). 
     In this example, the vehicle also includes a longitudinally mounted engine  130  (e.g., a six cylinder longitudinally mounted engine  130 ). Such an engine  130  may be compliant with, for example, environmental protection agency requirements. 
     As is shown, the vehicle  100  can be considered to be a single-deck vehicle having forward and rearward passenger doors  140 ,  142  (in some examples, only a forward door may be provided). The vehicle  100  further includes a vertical exit exhaust  150 . In addition, the vehicle  100  includes an air conditioning system  160 , which is mounted external to the vehicle  100 . The conditioning system  160  is provided in a middle region of the roof of the vehicle  100  and distanced from the engine so as to assist with even weight distribution. 
       FIG. 2  shows a plan view of a passenger deck  170  of such a vehicle  100  (e.g., a 30 ft vehicle). As is shown, the passenger deck  170  of the vehicle includes a number of passenger seats  175  (in the example, 24 passenger seats are shown, although more may be provided using a different configuration).  FIG. 3  shows a side view of the passenger deck  170 . 
     As is shown, the vehicle  100  further includes front wheel arch regions  180 , beneath which the front axle  110  and front wheels are located. The upper surface of the wheel arch regions  180  may serve as additional seating and/or may serve to allow storage or the like (e.g., baggage storage). In order to maximize the space within the vehicle  100 , it can be useful for any wheel axle  110  and suspension arrangement to occupy the minimum space possible. However, minimizing the space used should ideally not compromise the ride and handling capabilities of the vehicle. Such packaged suspension arrangements may also assist in reducing the overall length of the vehicle, as well as minimizing the unladen weight of the vehicle. 
       FIG. 4  shows a perspective view of the underside of the front of the vehicle  100  and, in particular, the front axle  110  and compact and effective suspension arrangement  200 , as will be further described. For clarity, the body and remainder of the vehicle  100  have been omitted from these Figures. Here, a front portion of a chassis  190  is shown, which includes a passenger entrance side  210  and a driver side  220  (right and left-hand sides, or near and far sides, respectively) upon which a platform allows a driver&#39;s seat, etc., to be constructed. As is shown, the chassis  190  at the passenger entrance side  210  has an aperture  215  defined between a forward most strut  217  of the chassis  190  and the wheel region  219  of the chassis  190 , such that a passenger ramp, or the like, may be fitted to the vehicle  100 , if desired (see also  FIG. 6 ). 
       FIG. 5  shows a front view of the suspension arrangement  200  and front chassis  190 , while  FIG. 6  shows a plan view.  FIG. 7  shows the section A-A,  FIG. 8  shows section B-B,  FIG. 9  shows section C-C,  FIG. 10  shows section D-D, and  FIG. 11  shows section E-E, as is shown in  FIGS. 5-6 . Reference numerals for the same features are common throughout the Figures. 
     The suspension arrangement  200  includes two suspension mounts  230   a,    230   b,  a left-hand mount  230   a  and a right-hand mount  230   b,  as will be explained.  FIGS. 12-14  show the left-hand suspension mount  230   a,  while  FIGS. 15-17  show the right-hand suspension mount  230   b.    
     The suspension mounts  230   a,    230   b  are configured to attach an axle  240 , which, in this example, is a drop-beam axle  240 . In this example, the axle  110  is configured with a braking system, as well as allows for steering of the vehicle  100 . 
     Here, the mounts  230   a,    230   b  include axle mount portions  245  to allow the mounts to attach to the axle  240 . Here, this is achieved using preformed apertures  260  in the axle mount portions  245 . Those apertures  260  can be used to attach and mount the suspension mounts (in this case using bolts  250 ) to the axle  240 . In some examples, the axle mount portions  245  are configured such that they are essentially flat (e.g., machined flat) so as to attach to a corresponding flat (e.g., machined flat) region of the axle  240 . 
     Here, and as is shown in  FIGS. 8-9 , the suspension mounts  230   a,    230   b  are additionally configured to mount with suspension link arms  310 ,  320 , which, in turn, effectively attach the axle  240  to the chassis  190 . Here, two link arms  310 ,  320  are provided, which in this example are fixed link arms with each mount and attach to the respective mounts  230   a,    230   b  using preformed apertures  260  in the mount  230   a.  Here, the links  310 ,  320  can be considered to be configured roughly parallel to one another and pivotable so as to allow the axle to travel in generally vertical direction with respect to the chassis  190 . Here, the links  310 ,  320  may be considered to be radius arm links and may be roughly less than 40 cm long (e.g., roughly 36 cm). 
     The suspension mounts  230   a,    230   b  are further configured to mount air springs  330 , or the like, with the axle  240 . In this example, each suspension mount  230   a,    230   b  includes a dished surface  255  configured to allow mounting of the air spring  330  thereto (e.g., bolting of the spring to the mount). Here, the dished surface  255  can be considered to be a partial dish, extending roughly 270 degrees for each mount  230   a,    230   b,  as is shown in  FIGS. 12-17 . Here, one or both of the air springs  330  are configured to deflate (e.g., upon user request) so as to effectively lower the front of the vehicle  100  to a kneeling configuration. 
     Further, each dished surface  255  is angled from a body axis of the suspension mount  230   a,    230   b.  Such a configuration can permit a compact suspension arrangement, yet also helpfully balance the angle of compression of each of the air springs  330  from a central line  270  of the axle  240 . The angle from the body axis may be between 90 and 100 degrees, such as between 95 and 100 degrees. In this example, the angle from the body axis can be considered to be roughly 98 degrees. The suspension arrangement is configured such that, when mounted, each air spring  330 , or the like, is essentially housed between the dished portion  255  and a portion of the chassis  190 . 
     Each suspension mount  230   a,    230   b  is further configured so as to mount suspension dampeners (e.g., telescoping dampeners) between the axle  240  and the chassis  190 . In this example, a single dampener is provided and is attached to each mount  230   a,    230   b  using preformed apertures  260 . In other examples, more dampeners may be used. 
     In addition to the above, the right-hand mount  230   b  (i.e., on the left of  FIG. 9  and as is shown in  FIGS. 15-17 ) further includes an extended lug  280 , depending from the axle-mount portion  245 . The extended lug also includes mounting apertures  285  configured to mount a Panhard rod  286 , or the like, between the axle  240  and the chassis  190 , as is shown (e.g., see  FIG. 9 ). Each mount further includes apertures  290  to permit mounting of the axle  240  with an anti-roll device (e.g.,  295 ), provided on depending lugs. Of course, in other examples, such a depending lug may be provided on the other mount  230   a.    
     As is shown in  FIGS. 12-17 , each suspension mount  230   a,    230   b  essentially includes a body portion  265  that extends between the dished surface  255  and an axle-mount portion  245 . In each case, the body portion  265  includes one or more curved ribs (in this example four ribs are used). The ribs provide for a rigid mount, but while minimizing weight. Here, each suspension mount can be considered to be a unitary mount (e.g., from a single cast). 
     The suspension mounts may be unitary (e.g., formed from a single cast) and provided with a number of preformed apertures to allow for mounting to one or more of the following: suspension arm links, such as radius arms links, suspension air springs, suspension dampeners (e.g., telescoping dampeners), anti-roll bars, Panhard rods, or the like. As such, the vehicle suspension arrangement can include one or more of the following: suspension arm links, such as radius arms links, suspension air springs, suspension dampeners (e.g., telescoping dampeners), anti-roll bars, Panhard rods, or the like, mounted with the chassis and the axle, using the suspension mount. 
     Providing a suspension arrangement and mount according to the features outlined above provides a suspension arrangement that is cost effective and can be installed in a limited space so as not to unduly restrict occupancy of the vehicle or space within the vehicle, yet at the same time provide both good ride and handling characteristics. In addition, the use of a unitary mount with preformed apertures improves the ease with which vehicles can be constructed, as well as improves manufacturing compliance and tolerances. 
     It will be appreciated by a skilled reader that individual features of the above described suspension apparatus  200  and chassis  190  may be used in combination, without the need for all the features disclosed in the various figures being essential to provide the benefits of an improved suspension arrangement and passenger service vehicle. 
       FIGS. 18-21  show various side and plan views of a rear-axle suspension arrangement  400 , through sections, which may optionally be used with the vehicle  100 . In this example, the rear-axle can be considered the drive axle. Here, links  410   a - 410   d,  which may be considered fixed links, attach the chassis to, in this case, a rear differential  420 , which in turn is connected to a drive shaft and the rear wheels.  FIGS. 22-23  show the associated drivelines from the rear-axle to the rear of the vehicle for two differing gearbox configurations, demonstrating the ability to achieve a short rear overhang with transverse mounted engine. 
     It will be appreciated that any of the aforementioned mounts, springs, dampeners, etc. may have other functions in addition to the mentioned functions and that these functions may be performed by the same mount/spring/dampener. 
     The applicant hereby discloses in isolation each individual feature described herein, and/or disclosed in the associated Figures, and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of any claims. The applicant indicates that aspects of the invention may consist of any such individual feature or combination of features. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention. 
     Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.