SE2151622A1 - Vehicle arrangement and vehicle comprising a vehicle arrangement - Google Patents

Abstract

A vehicle arrangement (10) comprising a first frame (2), a second frame (3) mounted to the first frame (2), and a friction damper (6). The friction damper (6) comprises a first plate-like member (8) attached to the first frame (2) and comprising a first portion (8a) having a first friction surface (8b) arranged so as to face towards the second frame. The friction damper further comprises a second friction surface (9b) arranged so as to abut the first friction surface (8b), said second friction surface (9b) formed by a surface arranged on the second frame (3) or by a surface of an optional second member (9) that is attached to the second frame (3). The friction damper (6) also comprises a force applying device (11) configured to apply a force to the first plate-like member (8) in a direction towards the second friction surface (9b). The present disclosure further relates to a vehicle (1) comprising a vehicle arrangement (10).

Description

VEHICLE ARRANGEMENT AND VEHICLE COMPRISING A VEHICLE ARRANGEMENT TECHNICAL FIELD The present disclosure relates in general to a vehicle arrangement comprising a first frame and a second frame mounted to each other. The present disclosure further relates in general to a vehicle comprising such a vehicle arrangement.

BACKGROUND Heavy vehicles, such as trucks or buses, generally comprises a chassis frame and a subframe. The chassis frame, also known as main frame, typically comprises two longitudinal members adapted to extend along the length of the vehicle and being connected to each other by a plurality of cross members which provide the required strength, stiffness, and torsional rigidity to the chassis frame. The subframe is an additional frame mounted on top of the chassis frame. The subframe, also known as auxiliary frame, can extend only a part of the length of the chassis frame or cover the entire chassis frame. Like the chassis frame, the subframe may typically comprise two longitudinal members connected by a plurality of cross members. The primary purpose of the subframe is to protect the chassis frame by evenly distributing the load from bodywork on the vehicle and load from any cargo. The subframe may also be used for mounting bodywork, such as a cargo box, a swap body, a supporting frame for carrying e.g. timber, or machinery such as a crane or the like, on the vehicle.

The subframe is typically mounted to the chassis frame by a plurality of attachment arrangements. The type of attachment arrangements used, as well as the position thereof and combination of different type of attachment arrangements may be selected depending on desired characteristics of the vehicle. For example, rigid attachments, which are configured to not allow any relative movement between the chassis frame and the subframe, may typically be used at the rear part of the vehicle, whereas flexible attachment arrangements may typically be used in the front part of the vehicle. Flexible attachment arrangements may for example be designed to allow a limited movement between the chassis frame and the subframe in a vertical direction of the vehicle and/or in the longitudinal direction of the vehicle.

While driving, the chassis frame and the subframe are exposed to various types of forces which may cause vibrations. Sources of vibration may be road conditions or various constituent components of the vehicle. These vibrations may cause one or more of the frames to osci||ate if the source of vibration has a frequency that coincides with the natural frequency of said one or more frames due to resonance. Frame resonances in the vertical direction of the vehicle and in the range about 4-10 Hz is a common problem for heavy vehicles. These vertical frame resonances can be a significant contribution to poor comfort, in particular by resulting in vibrations to the cab of the vehicle that may be very disturbing to a driver of the vehicle. ln order to reduce the risk for vertical frame resonances, some type of damping between the chassis frame and the subframe is needed. lt has previously been proposed to create friction damping in the horizontal contact plane between the chassis frame and the subframe. However, in unladen condition, there is very little gravitational force to create friction between the chassis frame and the subframe. Furthermore, the flexible attachment arrangements used generally offer very little force to create friction or stiffening cooperation between the frames. Also, the subframe and/or the chassis frame may not be completely straight in the horizontal-longitudinal direction, which can cause a lack of contact for considerable portions of the length, especially in unladen condition.

SUMMARY The object of the present invention is to reduce the risk for vertical frame resonances in a vehicle or at least reduce the effect of such vertical frame resonances.

The object is achieved by the subject-matter of the appended independent claim(s). ln accordance with the present disclosure, a vehicle arrangement comprising a first frame and a second frame, mounted to each other by a plurality of attachment arrangements, is provided. The vehicle arrangement comprises a friction damper formed by: a first plate-like member attached to the first frame and comprising a first portion having a first friction surface arranged so as to face towards the second frame, a second friction surface arranged so as to abut the first friction surface, said second friction surface formed by a surface arranged on the second frame or by a surface of an optional second member that is attached to the second frame, and a force applying device configured to apply a force to the first plate-like member in a direction towards the second friction surface.

By means of the vehicle arrangement according to the present disclosure, friction damping is achieved in a plane which is substantially perpendicular to the contact plane between the first and second frames due to the configuration of the friction damper. Thus, the present vehicle arrangement does not rely on friction damping in the contact plane between the first frame and the second frame as previously relied upon (although friction damping in the contact plane between the first and second frames may also be achieved). Moreover, a considerable and arbitrary selected normal force can be applied to the friction surfaces of the friction damper as a result of the force applying device. Thus, the normal force between the first and second friction surfaces may be independent of the load of the vehicle and therefore present already in unladen condition. Furthermore, the friction damping between the frames can be considerable even if the contact between the first and second frames in the horizontal-longitudinal direction is inferior, for example due to poor straightness of the first and/or second frames.

The first plate-like member may comprise a first through-hole arranged in the first portion and the friction damper further comprise a first elongated fastener. Said elongated fastener may be arranged so as to extend perpendicular to the second friction surface and through the first through-hole of the first plate-like member. The first through-hole has a diameter greater than the diameter of the first elongated fastener so as to allow motion of the first plate-like member relative to the first elongated fastener in a plane parallel to the second friction surface.

The force applying device may comprise a spring element, for example a coil spring. Thereby, a reliable and controlled force may be applied to the first plate-like member by the force applying device.

The vehicle arrangement may further comprise an abutment arranged on the first elongated fastener and the spring element be arranged so as to circumscribe the first elongated fastener. ln such a case, the spring element may be configured to apply the force to the first plate-like member by applying a separating force between the abutment and the first plate-like member.

The force applying device may, in addition to or instead of the spring element, comprise an actuator configured to control the force applied to the first plate-like member. When the force applying device comprises such an actuator, there may be a possibility to vary the force applied to the first plate-like member, and hence the normal force of the first and second friction surfaces, in dependence of various factors, such as vehicle load, speed, road conditions or the like, if desired. ln case the vehicle comprises an abutment arranged on the first elongated fastener and the force applying device comprising both a spring element and an actuator, said actuator may be configured to control the force applied to the first plate-like member by changing the distance between the abutment and the first plate-like member.

The plurality of attachment arrangements of the vehicle arrangement may comprise a flexible attachment arrangement. The friction damper may be integrated with said flexible attachment arrangement such that the first plate-like member of the friction damper is arranged between the second frame and a first attachment member of the flexible attachment arrangement. Integrating the friction damper with a flexible attachment arrangement for example has the advantage of reducing the number of points at which attachment of components to the first and second frames needs to be made. Integrating the friction damper with a flexible attachment arrangement may also reduce the number of constituent components needed and therefore also result in lower cost, lower weight and faster assembly.

The first attachment member of the flexible attachment arrangement may comprise an opening through which the force applying device extend. Thereby, it ensured that the force applying device may apply a force to the first plate-like member without simultaneously applying an undesired force to the first attachment member that may affect the function of the flexible attachment arrangement.

According to a first alternative when the friction damper is integrated with a flexible attachment arrangement, the first attachment member is a support plate. Said support plate as well as the first plate-like member may be firmly attached to the first frame by a first set of fastening means. ln such a case, the flexible attachment arrangement may further comprise one or more support sleeves. Each of said one or more support sleeves is attached to the second frame and arranged so as to extend through a second through-hole of the support plate. Said second through-hole has a diameter greater than the diameter of the support sleeve extending therethrough to thereby allow a limited movement of the support plate in a radial direction of the support sleeve. Thereby, the flexible attachment arrangement may allow a limited relative motion of the first and second frames both in the vertical direction of the vehicle and in the longitudinal direction of the frames. lf the flexible attachment arrangement comprises a plurality of support sleeves, each support sleeve of the plurality of support sleeves may be attached to the second frame by a corresponding fastening means of a second set of fastening means. Said second set of fastening means may, via the support sleeves, also firmly attach the second member, if present, of the friction damper to the second frame.

According to a second alternative when the friction damper is integrated with a flexible attachment arrangement, the first attachment member is a first attachment bracket and the flexible attachment arrangement further comprises a second attachment member in the form of a second attachment bracket. ln such a case, the first plate-like member and the second attachment bracket may be firmly attached to the first frame by a first set of fastening means, and the first attachment bracket firmly attached to the second frame by a second set of fastening means via a p|ura|ity of spacers. The second attachment bracket is flexibly attached to the first attachment bracket via a fastening arrangement and at least one spring load. Thereby, the flexible attachment arrangement may allow a limited movement of the first and second frames both in a vertical direction of the vehicle and in a longitudinal direction of the frames. ln the vehicle arrangement described herein, one of the first and second frames may be a chassis frame, and the other of the first and second frames may be a subframe.

The present disclosure further provides a vehicle comprising the above-described vehicle arrangement. The vehicle may be a land-based heavy vehicle, such as a truck or bus.

BRIEF DESCRIPTION OF DRAWINGS Fig. 1 illustrates a side view of an example of a vehicle, Fig. 2 illustrates an expanded perspective view of a vehicle arrangement according to a first exemplifying embodiment of the present disclosure, Fig. 3 illustrates an expanded perspective view of a vehicle arrangement according to a second exemplifying embodiment of the present disclosure, Fig. 4a represents a front view of the vehicle arrangement shown in Fig. 3, Fig. 4b represents a side vide of the vehicle arrangement shown in Fig. 3, Fig. 4c represents a perspective view of the vehicle arrangement shown in Fig. 3, Fig. 5 illustrates an expanded perspective view of a vehicle arrangement according to a third exemplifying embodiment of the present disclosure, Fig. 6a represents a front view of the vehicle arrangement shown in Fig. 5, Fig. 6b represents a side vide of the vehicle arrangement shown in Fig. 5, Fig. 6c represents a perspective view of the vehicle arrangement shown in Fig. 5, and Fig. 7 illustrates an expanded perspective view of a vehicle arrangement according to a fourth exemplifying embodiment of the present disclosure.

DETAILED DESCRIPTION The invention will be described in more detail below with reference to exemplifying embodiments and the accompanying drawings. The invention is however not limited to the exemplifying embodiments discussed and/or shown in the drawings, but may be varied within the scope of the appended claims. Furthermore, the drawings shall not be considered drawn to scale as some features may be exaggerated in order to more clearly illustrate the invention or features thereof. ln accordance with the present disclosure, a vehicle arrangement comprising a friction damper is provided. A friction damper is in the present disclosure considered to mean a device configured to provide a damping effect to a relative motion between two objects by conversion of kinetic energy into thermal energy. Friction damping occurs at the interface between two bodies in relative (sliding) motion with contact. The friction force opposes the relative velocity direction and depends on the normal force between the bodies. The friction damper according to the present disclosure may be a dry friction damper. A dry friction damper is a friction damper relying on the friction created at the interface between the bodies without any type of purposively added additive to the interface (such as a lubricant or the like) and thereby relying on the respective friction coefficients provided by the friction surfaces forming the interface. lt should however be noted that the interface between the bodies of such a dry friction damper may become wet, or be exposed to other matters that may influence the friction (such as dirt), due to normal exposure when in use.

More specifically, the present disclosure provides a vehicle arrangement comprising a first frame and a second frame, said first and second frames mounted to each other by a plurality of attachment arrangements, and a friction damper configured to provide a damping effect to a possible relative motion between the first and second frames. The friction damper comprises a first plate-like member, firmly attached to the first frame, and comprising a first portion having a first friction surface arranged so as to face towards the second frame. The friction damper further comprises a second friction surface arranged so as to abut the first friction surface. The second friction surface may be formed by a surface arranged on the second frame or by a surface of an optiona| second member that is attached to the second frame. One or both of the first and second friction surfaces may comprise a material having a relatively high friction coefficient. The friction damper further comprises a force applying device configured to apply a force to the first plate-like member in a direction towards the second friction surface. More specifically, the force applying device may be configured to apply a force to the first portion of the first plate-like member and in a direction towards the second friction surface. The force applying device is thus configured to influence the normal force between the first friction surface and the second friction surface of the friction damper.

The second friction surface may be arranged so as to abut the first friction surface in an abutment plane which is substantially perpendicular to a first plane, said first plane representing a contact plane between the first frame and the second frame of the vehicle arrangement. Moreover, said first plane may be substantially parallel to a horizontal plane of a vehicle comprising the vehicle arrangement. Furthermore, said abutment plane may be substantially parallel to a longitudinal direction of a vehicle comprising the vehicle arrangement. ln the vehicle arrangement described herein, one of the first and second frames may be a chassis frame of a vehicle, and the other of the first and second frames be a subframe of the vehicle. According to one alternative, the first frame is a chassis frame and the second frame is a subframe. According to another alternative, the first frame is a subframe and the second frame is a chassis frame.

The friction damper may further comprise a first elongated fastener arranged so as to extend perpendicular to the second friction surface. Said first elongated fastener may suitably be fastened to the second frame. Furthermore, the first plate-like member of the friction damper may comprise a first through-hole arranged in the first portion. The first elongated fastener may in such a case be arranged so as to extend the first through-hole of the first plate-like member. The first through-hole in the first plate-like member has a diameter which is greater than the diameter of the first elongated fastener to thereby allow motion of the first plate-like member relative to the first elongated fastener. Thus, the fact that the first through-hole of the first plate-like member has a diameter that is greater than the diameter of the first elongated fastener also ensures that the first and second frictions surfaces may be moved relative to each other in a sliding motion. The first elongated fastener may serve the purpose of limiting the possible relative motion of the first and second friction surfaces relative to each other, if desired. However, more importantly, the first elongated fastener may serve the purpose of ensuring the position of the force applying device in relation to the first and second friction surfaces.

The force applying device may comprise a spring element, such as a coil spring or a rubber bushing. Said spring element may for example be arranged so as to circumscribe the first elongated fastener and be held in place by an abutment, for example a nut or a bolt, arranged on the first elongated fastener. lf present, the abutment constitutes a constituent component of the force applying device. The force applying device may be configured to apply the force to the first plate-like member by the spring element being configured to apply the force to the first plate-like member by applying a separating force between the abutment and the first plate-like member. By controlling the tension of the spring element by selecting the position of the abutment, the force applied by the force applying device to the first plate-like member may be controlled. lf desired, a washer may be arranged between the spring element and the abutment in order to ensure an even distribution of the force between the spring element and the abutment.

The force applying device may, in addition to the spring element, further comprise an actuator configured to control the force applied to the first plate-like member. The actuator may for example be a pneumatically controlled actuator or a hydraulically controlled actuator, but is not limited thereto. The actuator may be configured to control the force applied to the first plate-like member by changing the distance between the abutment and the first plate-like member. The actuator may be configured to adjust the spring force provided by the spring element of the force applying device. lt should here be noted that the force applying device need not necessarily comprise a spring element, although this is preferred in order to safely ensure a minimum force applied to the first plate-like member. For example, the force applying device may comprise an actuator configured to control the force applied to the first plate-like member without the use of a spring element. ln such a case, the actuator may also be configured to control the force applied to the first plate-like member by changing the distance between the above-described abutment and the first plate-like member.

The present disclosure is however not limited thereto, and other solutions for how such an actuator of the force applying device may apply the force to the first plate-like member in the direction of the second friction surface are plausible. ln case the force applying device comprises an actuator (irrespectively of whether also comprising a spring element or not), it is possible to adapt or vary the force applied to the first plate-like member, and thereby influence the normal force between the first and second friction surfaces, in dependence of various factors also during driving of a vehicle comprising the vehicle arrangement. Examples of such factors include, but are not limited to, driving conditions of the vehicle (such as traveling speed), road conditions (including terrain), vehicle load, and/or detected oscillations of one or both frames of the vehicle arrangement. The actuator may suitably be controlled by a controller in dependence of information received relating to such factors and/or in dependence of driver-initiated requests.

As mentioned above, the first frame and the second frame of the vehicle arrangement are mounted to each other by a plurality of attachment arrangements. The plurality of attachment arrangements may comprise at least one flexible attachment arrangement. The above-described friction damper may for example be arranged next to the at least one flexible attachment arrangement as seen in a longitudinal direction of the first and second frames. However, more suitably, the friction damper is integrated with said at least one flexible attachment arrangement. Integrating the friction damper in a flexible attachment arrangement has the advantage of reducing the number of points along the longitudinal extension of the frames at which attachment of components to the first and second frames needs to be made. lt may also enable using fewer constituent components as some constituent components may be shared by the friction damper and the flexible attachment arrangement, and thereby allow a lower cost and weight compared to arranging the friction damper and flexible attachment arrangement at separate locations within the vehicle arrangement. Furthermore, depending on the configuration of the flexible attachment arrangement, it may have the advantage of enabling achieving a damping effect both in a contact plane between the first and second frames as well as a plane perpendicular thereto at the same position along the longitudinal extension of the first and second frames. Suitably the friction damper is integrated with the at least one flexible attachment arrangement such that the first plate-like member of the friction damper is arranged between the second frame and a first attachment member of the flexible attachment arrangement. Said first attachment member may suitably comprise an opening through which the force applying device of the friction damper may extend. Said opening is preferably sufficiently large to allow a certain movement of the first attachment member relative to the force applying device. By means of the opening in the first attachment member, it is ensured that the force applying device may apply a force to the first attachment member of the flexible attachment arrangement without also applying a force to the first attachment member and thereby possibly also influencing the function of the flexible attachment arrangement as such.

The flexible attachment arrangement, in which the friction damper may be integrated, may have different plausible configurations.

According to a first alternative of a vehicle arrangement wherein the friction damper is integrated with a flexible attachment arrangement, the first attachment member is a support plate which is firmly attached to the first frame. Suitably, the support plate may be firmly attached to the first frame by a first set of fastening means which is also used for firmly attaching the first plate-like member of the friction damper to the first frame. The opening of said support plate through which the force applying device extend, as mentioned above, may suitably be in the form of a first through- opening. The flexible attachment arrangement further comprises one or more support sleeves, wherein each of said one or more support sleeves is firmly attached to the second frame. Moreover, each of said one or more support sleeves is arranged to extend through a respective second through- hole of the support plate. Said second through-hole has a diameter greater than the diameter of the support sleeve extending therethrough to thereby allow a limited movement of the support plate in a radial direction of the support sleeve. Preferably, at least two support sleeves are present, said two support sleeves arranged on opposite sides of the first though-opening (and hence the force applying device of the friction damper) as seen in parallel to a longitudinal extension of the second frame. When the flexible attachment arrangement comprises a plurality of support sleeves (i.e. at least two support sleeves), each of said plurality of support sleeves may be attached to the second frame by a corresponding fastening means from a second set of fastening means. lf the friction damper comprises the second member comprising the second friction surface, said second set of fastening means may also be configured to firmly attach said second member to the second frame. ln such a case, the second member may be firmly attached to the second frame by being clamped thereto by means of the support sleeves and the second set of fastening means.

According to a second alternative of a vehicle arrangement wherein the friction damper is integrated with a flexible attachment arrangement, the first attachment member is a first attachment bracket and the flexible attachment arrangement further comprises a second attachment bracket (which constitutes a second attachment member). The second attachment bracket is firmly attached to the first frame by a first set of fastening means. Said first set of fastening means may also be used for firmly attaching the first plate-like member of the friction damper to the first frame. The first plate- 11 like member of the friction damper is arranged between the first frame and the second attachment bracket. The first attachment bracket is firmly attached to the second frame by a second set of fastening means via a plurality of spacers. The plurality of spacers are suitably arranged on opposite sides of the first portion of the first plate-like member as seen in parallel to a longitudinal extension of the second frame. The spacers ensures that the first attachment bracket may be firmly attached to the second frame despite the fact that the first plate-like member of the friction damper is arranged between the second frame and the first attachment bracket. Furthermore, the second attachment bracket is flexibly attached to the first attachment bracket via a fastening arrangement and at least one spring load. Thereby, the first and second attachment brackets allows a limited and damped relative movement between the first and second frames both in the vertical direction and in the longitudinal direction of the first and second frames. ln the exemplified embodiments described below with reference to the accompanying drawings, the vehicle arrangement according to the present disclosure is for sake of ease of clarity illustrated for a case where the first frame constitutes a chassis frame of a vehicle, and the second frame constitutes a subframe. lt should however be recognized that the present disclosure is not limited thereto, as also described above. For example, the first frame may instead constitute a subframe and the second frame constitute a chassis frame.

Figure 1 illustrates a side view of an example of a vehicle 1. The vehicle 1 comprises a first frame 2 and a second frame 3. As mentioned above, the first frame 2 is here illustrated as a chassis frame and the second frame 3 as a subframe. The second frame 3 may for example serve the purpose of enabling coupling of a cargo box 7 or the like to the vehicle 1. The first frame 2 and the second frame 3 are mounted to each other by a plurality of attachment arrangements. Said plurality of attachment arrangements may comprise one or more rigid attachment arrangements 4. Said plurality of attachment arrangements may additionally or alternatively comprise one or more flexible attachment arrangements 5. ln case the vehicle comprises both rigid attachment arrangements and flexible attachment arrangements, the rigid attachment arrangements are usually arranged in the rear part of the vehicle whereas the flexible attachment arrangements are arranged in the front half of the second frame as shown in the figure.

A rigid attachment arrangement may typically be formed of a rigid plate which is welded or bolted to one of the first frame 2 and second frame 3, and bolted to the other one of the first frame 2 and the second frame 3. A rigid attachment arrangement is thereby not intended to allow any relative movement between the first frame 2 and the second frame 3 at the position of the rigid attachment 12 arrangement. ln contrast, a flexible attachment arrangement is configured to allow a limited relative motion between the first frame 2 and the second frame 3. Flexible attachment arrangements 5 may have different configurations. One commonly known example of a flexible attachment comprises two L-shaped elements, each firmly attached to a respective one of the first frame 2 and second frame 3 and arranged in mirror to each other so as to face each other in a contact plane between the first frame 2 and the second frame 3, said L-shaped elements held together by a spring force. Such L- shaped elements may alternatively be described as attachment brackets.

The vehicle 1 illustrated in Fig. 1 comprises a longitudinal direction. The longitudinal direction of the vehicle 1 is parallel to a flat horizontal support surface when the vehicle 1 is positioned in an upright use position onto the flat horizontal support surface. Wheels of the vehicle 1 are abutting against the flat horizontal support surface when the vehicle 1 is positioned in the upright use position onto the flat horizontal support surface. The longitudinal direction of the vehicle 1 coincides with a forward and reverse driving direction of the vehicle 1.

The vehicle 1 also comprises a lateral direction. The lateral direction is perpendicular to the longitudinal direction and is perpendicular to a vertical direction of the vehicle 1. ln other words, the lateral direction of the vehicle 1 is parallel to a flat horizontal support surface when the vehicle 1 is positioned in the upright use position onto the flat horizontal support surface. The lateral direction of the vehicle 1 may also be referred to as a horizontal direction of the vehicle 1. As evident from the above, a horizontal plane of the vehicle 1 is defined by the longitudinal direction and the lateral direction. ln other words, a horizontal plane of the vehicle is parallel to the flat horizontal support surface when the vehicle 1 is positioned in an upright use position onto the flat horizontal support surface.

Moreover, the vertical direction of the vehicle 1 is parallel to a surface normal vector of the flat horizontal support surface when the vehicle 1 is positioned in the upright use position onto the flat horizontal support surface. ln other words, the vertical direction of the vehicle 1 is perpendicular to the flat horizontal support surface when the vehicle 1 is positioned in the upright use position thereon. Moreover, a vertical plane of the vehicle 1 is perpendicular to the flat horizontal support surface when the vehicle 1 is positioned in the upright use position thereon.

Figure 2 illustrates an expanded perspective view of a vehicle arrangement 10 according to a first exemplifying embodiment of the present disclosure. The vehicle arrangement 10 may be a vehicle 13 arrangement of for example the vehicle 1 illustrated in Figure 1. The vehicle arrangement comprises a first frame 2 a second frame 3, and a friction damper 6. ln the vehicle arrangement 10, the second frame 3 is mounted to the first frame 2 by a plurality of attachment arrangements (not shown in the figure), for example as shown in Figure 1. The first frame 2 and the second frame 3 are arranged on opposite sides of a first plane P1. The first plane P1 represents the contact surface between the first frame 2 and the second frame 3 when they are in contact with each other. The first plane P1 may also be referred to as a first contact plane between the first frame 2 and the second frame 3. The first plane P1 may typically coincide with or be substantially parallel to a horizontal plane of a vehicle comprising the vehicle arrangement 10, such as the vehicle 1 shown in Figure 1. Thus, the first plane P1 may be considered to represent a horizontal first plane.

Furthermore, each of the first frame 2 and the second frame 3 has a longitudinal extension. The longitudinal extension of the first frame 2 is substantially parallel to the longitudinal extension of the second frame 3, at least for a portion thereof where the friction damper 6 is arranged. Moreover, the longitudinal extensions of the first frame 2 and the second frame 3 are substantially parallel to said first plane P1. The longitudinal extension of the second frame 3 is illustrated by the double arrow L in the Fig. 2. The longitudinal extensions of the first frame 2 and the second frame 3 are substantially parallel to the longitudinal direction of the vehicle 1 illustrated in Fig. 1.

As mentioned above, the vehicle arrangement 10 comprises a friction damper 6. The friction damper 6 comprises a first plate-like member 8 firmly attached to the first frame 2, for example by a first set of fastening means or by being welded thereto. Such a first set of fastening means is in the figure exemplified by a plurality of bolts 19a and nuts 19b, the bolts 19a configured to extend through corresponding through-holes 8c in the first plate-like member 8. The first plate-like member 8 is arranged perpendicular to, and transverses, the first plane P1. The first plate-like member 8 may thus be considered to be arranged in parallel to the longitudinal extension of the first frame 2 as well as in parallel to the longitudinal extension of the second frame 3. The first plate-like member 8 has a first frictional surface 8b arranged at least in a first portion 8a of the first plate-like member 8. The first plate-like member 8 is arranged so that said first portion 8a is arranged on a side of the first plane P1 opposite to the side of the first plane P1 where the first plate-like member 8 is attached to the first frame 2. As shown in the figure, the first frictional surface 8b is arranged so as to face the second frame 3. Furthermore, the first frictional surface 8b may be described to be arranged perpendicular to the first plane P1. 14 The friction damper 6 further comprises a second friction surface 9b arranged so as to abut the first friction surface 8b. The second friction surface 9b may be arranged so as to abut the first friction surface 8b in an abutment plane being substantially perpendicular to the first plane P1. Moreover, the abutment plane between the first and second friction surface 8b, 9b may be substantially parallel to the longitudinal direction of the vehicle comprising the vehicle arrangement 10. The second friction surface 9b may be a surface of a second member 9 of the friction damper 6 as shown in the figure. Alternatively, the second friction surface 9b may be formed by a surface directly on the second frame 3. ln the latter case, the friction damper 6 does not comprise the second member 9. lf present, the second member 9 may be welded to the second frame 3 or attached thereto by a one or more fastening means, such as a second set of fastening means comprising a plurality of bolts 18a and nuts 18b as illustrated in the figure. ln case the vehicle arrangement 10 does not comprise the second member 9, the illustrated bolts 18a and nuts 18b serves no purpose according to the first exemplifying embodiment and may therefore be omitted. The friction damper 6 further comprises a force applying device 11 configured to apply a force to the first plate-like member in a direction towards the second friction surface 9b, as will be further described below.

For the purpose of ensuring that the first friction surface 8b abuts the second friction surface 9b, for example in case of presence of the second member 9 and/or a difference in vertical longitudinal planes of the first frame 2 and the second frame 3, the vehicle arrangement 10 may further comprise a distance member 16 arranged between the first frame 2 and the first plate-like member 8. The vertical longitudinal plane of first frame 2 substantially coincides with the two-dimensional extension of the surface 2a illustrated in the figure. Such a vertical longitudinal plane typically corresponds to a vertical longitudinal plane of a vehicle comprising the vehicle arrangement 10 (such as the vehicle 1 illustrated in Figure 1), which in turn is a plane parallel to the vertical direction and parallel to the longitudinal direction of the vehicle. Similarly, the vertical longitudinal plane of the second frame 3 substantially coincides the with the two-dimensional extension of the surface 3a illustrated in the figure. Moreover, said vertical longitudinal planes of the first frame 2 and the second frames 3, respectively, may typically each be substantially perpendicular to the first plane P1. The distance member 16 may suitably be attached to the first frame 2 by the above-described first set of fastening means 19a, 19b. The distance member 16 is, if present, arranged between the first frame 2 and the first plate-like member 8.

The first plate-like member 8 further comprises a first through-hole 12 arranged in the first portion 8a thereof. A first elongated fastener 13, such as a screw or a bolt, is arranged so as to extend perpendicular to and from the second friction surface 9b, and through the first through-hole 12 of the first plate-like member 8. The first through-hole 12 has a diameter which is greater than the diameter of the first elongated fastener 13. Thereby, the first through-hole 12 allows motion of the first plate-like member 8 relative to the first elongated fastener 13 in a plane parallel to the second friction surface 9b. More specifically, the first through-hole 12 allows motion of the first plate-like member 8 relative to the first elongated fastener 13 in a plane parallel to the first friction surface 8b of the first plate-like member 8, i.e. a plane parallel to the above-mentioned abutment plane. ln other words, the first friction surface 8b may be moved in relation to the second friction surface 9b in a sliding manner.

The friction between the first friction surface 8b and the second friction surface 9b of the friction damper 6 creates a damping effect to the relative movement between the first frame 2 and second frame 3, both in a direction parallel to the longitudinal extensions of the first frame 2 and the second frame 3, and in a vertical direction of the first frame 2 and the second frame 3. Here, it should be noted that the vertical direction of the first and second frames 2, 3 correspond to a vertical direction of a vehicle comprising the vehicle arrangement 10 (such as the vehicle 1 illustrated in Figure 1). Said damping effect is, in addition to the friction coefficient of the first and second friction surfaces 8b, 9b, dependent of the normal force between the first and second friction surfaces 8b, 9b. For the purpose of controlling said normal force, the friction damper 6 comprises a force-applying device 11. The force applying device 11 may comprise a spring element 14, such as a coil spring (as illustrated in the figure), a rubber bushing or the like. Said spring element 14 may be arranged so as to circumscribe the first elongated fastener 13. An abutment 15, such as a nut, may be arranged on the first elongated fastener 13. The spring element 14 may be configured to apply a force to the first plate-like member 8 by applying a separating force between said abutment 15 and the first plate-like member 8. Thereby, the normal force between the first and second friction surfaces 8b, 9b is influenced. By controlling the tension of the spring element by means of the abutment 15, the normal force between the first and second friction surfaces 8b, 9b is controlled. A first washer 17 may optionally be interposed between the spring element 14 and the abutment 15 for the purpose of facilitating an even distribution of the force between the spring element 14 and the abutment 15. lf desired, a second washer (not illustrated) may be arranged between the spring element 14 and the first plate-like member 8. As evident from the above, the first elongated fastener 13, the spring element 15, the abutment 15 and the optional first washer 14 together forms the force applying device 11. 16 lt should here be noted that the force applying device of the friction damper 6 is not limited to one having the configuration illustrated in Figure 2. For example, the force applying device may be in the form of an actuator (for example a pneumatically or hydraulically controlled actuator) configured to apply a force to the first plate-like member 8 to thereby influence the normal force between the first and second friction surfaces 8b, 9b of the friction damper. Alternatively, the force applying device 11 may also comprise both a spring element and an actuator (compare with Figure 7). ln the latter case, the actuator may be configured to control the force applied to the first plate-like member by changing the distance between the abutment 15 and the first plate-like member 8.

Figure 3 illustrates an expanded perspective view of a vehicle arrangement 10 according to a second exemplifying embodiment of the present disclosure. The vehicle arrangement 10 illustrated in Figure 3 may be a vehicle arrangement of the vehicle 1 illustrated in Figure 1. The second exemplifying embodiment corresponds to the first exemplifying embodiment described above with reference to Figure 2, except that the friction damper 6 is integrated with a flexible attachment arrangement 5 (compare with Figure 1). More specifically, the friction damper 6 is integrated with the flexible attachment arrangement 5 in such a way that the first plate-like member 8 of the friction damper 6 is arranged between the second frame 3 and a first attachment member of the flexible attachment arrangement 5, said first attachment member constituting a support plate 20.

The support plate 20 of the flexible attachment arrangement 5 is firmly attached to the first frame 2. More specifically, the support plate 20 may be attached to the first frame 2 by the same first set of fastening means that also firmly attaches the first plate-like member 8 of the friction damper 6 to the first frame 2, said first set of fastening means illustrated by the bolts 19a and cooperating nuts 19b.

The support plate 20 is arranged so as to transverse the first plane P1 (see Figures 4a and 4b).

The support plate 20 comprises an opening, more specifically a first through-opening 21, through which the force applying device 11 of the friction damper 6 may extend. Thereby, the force applying device 11 may apply a force to the first plate-like member 8 without simultaneously applying a force to the support plate 20. The first through-opening 21 of the support plate 20 has a diameter sufficiently large to allow movement of the support plate 20 relative to the force applying device in a radial direction of the first through-opening 21.

The flexible attachment arrangement 5 further comprises one or more support sleeves 33, each of said one or more support sleeves 33 arranged so as to extend through a respective second through- hole 36 of the support plate 20 and being attached to the second frame 3. The one or more support 17 sleeves 33 suitably have a cylindrical outer surface. The second through-hole opening 36 has a diameter greater than the diameter of the support sleeve 33 extending therethrough to thereby allow a limited movement of the support plate 20 in the radial direction of a support sleeve 33. Thereby, the support plate 20 together with the one or more support sleeves 33 will allow a limited relative movement between the first frame 2 and second frame 3 and therefore together form a flexible attachment arrangement 5.

As mentioned above, each of the one or more support sleeves 33 is attached to the second frame 3. This may suitably be made by the second set of fastening means, illustrated by the bolts 18a and corresponding nuts 18b, which also attaches the second member 9 of the friction damper 6 if this is present. ln contrast to the first exemplifying embodiment shown in Figure 2, the second set of fastening means may therefore serve a purpose of attaching the one or more support sleeves 33 even if the optional second member 9 is not present. ln addition to serving the purpose of allowing a limited movement of the support plate 20 in a radial direction of a support sleeve 33, the support sleeve 33 also ensures that the second member 9 (if present) is firmly clamped to the second frame 3 by the second set of fastening means 18a, 18b.

Figures 4a-4c represent a front view, a side view and a perspective view, respectively, of the vehicle arrangement 10 according to the second exemplifying embodiment illustrated in Figure 3 when assembled. The front view as shown in Figure 4a typically corresponds to a side view of the vehicle comprising the vehicle arrangement 10. From Figure 4b, it can be seen that the first plate-like member 8 is arranged substantially perpendicularly to, and crosses, the first plane P1. lt can also clearly be seen that the first plate like member 8 of the friction damper is arranged between the second frame 3 and the support plate 20. lt is also clear from Figures 4a and 4b that the support plate 20 of the flexible attachment arrangement 5 crosses the first plane P1.

Figure 5 illustrates an expanded perspective view of a vehicle arrangement 10 according to a third exemplifying embodiment of the present disclosure. The vehicle arrangement 10 illustrated in Figure 5 may be a vehicle arrangement of the vehicle 1 illustrated in Figure 1. Similar to the second exemplifying embodiment described above and shown in Figures 3 to 4c, the third exemplifying embodiment corresponds to the first exemplifying embodiment described above with reference to Figure 2, except that the friction damper 6 is integrated with a flexible attachment arrangement. However, compared to the second exemplifying embodiment, the third exemplifying embodiment has a different configuration of the flexible attachment arrangement as will be evident from the following. 18 More specifically, the flexible attachment arrangement 5 of the vehicle arrangement 10 according to the third exemplifying embodiment comprises a first attachment member in the form of a first attachment bracket 22 and a second attachment member in the form of a second attachment bracket 24. Each of the first and second attachment brackets 22, 24 may have a substantially L- shaped configuration, as shown in the figure. The first attachment bracket 22 is firmly attached to the second frame 3 whereas the second attachment bracket 24 is firmly attached to first frame. Moreover, the first attachment bracket 22 comprises an opening 23 through which the force applying device 11 may extend. Thereby, the force applying device 11 may apply a force to the first plate-like member 8 without simultaneously applying a force to the first attachment bracket 22.

The first attachment bracket 22 is firmly attached to the second frame 3 by the second set of fastening means, here illustrated by the bolts 18a and cooperating bolts 18b. Said second set of fastening means may also suitably be used for firmly attaching the second member 9 if the friction damper 6 comprises said second member 9. The first plate-like member 8 of the friction damper is arranged between the second frame 3 and the first attachment bracket 22, but is not attached to second frame 3 to ensure that the first friction surface 8b and the second friction surface 9b may be slidably moved in relation to each other. Therefore, in order to ensure that first attachment bracket may be firmly attached to the second frame 3, a plurality of spacers 38 are used together with the second set of fastening means 18a 18b.More specifically, a fastening means of the second fastening means is arranged so as to extend through a respective one of the spacers 38. The spacers 38 may each have a thickness greater than the thickness of the first plate-like member 8 so that attachment bracket 22 will have clearance and not restrict relative movement of the first plate-like member 8. Moreover, the spacers are suitably arranged on opposing sides of the first portion 8a (see Figure 2) of the first plate-like member 8 as seen in a plane perpendicular to the first plane P1. The second attachment bracket 24 is firmly attached to the first frame 2, suitably by means of the first set of fastening means (illustrated by the bolts 19a and cooperating nuts 19b) that is used for attaching the first plate-like member 8 to the first frame 2.

Each of the first and second attachment brackets 22, 24 may suitably be substantially L-shaped, as shown in the figure, and arranged such that one leg of the L-shape is firmly attached to a respective one of the first frame 2 and the second frame 3 whereas the other leg of the L-shape extends in a plane perpendicular to the first plane P1 (see Figure 6b). The first and second attachment brackets 22, 24 are flexibly attached to each other via a fastening arrangement and at least one spring load.

For example, the first and second attachment brackets may be flexibly attached to each other via a 19 third set of fastening means 40 clamping the first and second attachment brackets 22, 24 together via a spring load provided by for example one or more rubber bushings 41.

Figures 6a-6c represent a front view, a side view and a perspective view, respectively, of the vehicle arrangement 10 according to the third exemplifying embodiment illustrated in Figure 5 when assembled. The front view as shown in Figure 6a typically corresponds to a side view of the vehicle comprising the vehicle arrangement 10. From the perspective view shown in Figure 6c, it can be clearly seen how the spring 14 of the force applying device extends through the opening 23 of the first attachment bracket 22 and abuts the first plate-like member 8 for the purpose of applying a force thereto.

Figure 7 illustrates a partly expanded perspective view of a vehicle arrangement 10 according to a fourth exemplifying embodiment of the present disclosure. The illustrated vehicle arrangement may be a vehicle arrangement of the vehicle 1 illustrated in Figure 1. The fourth exemplifying embodiment corresponds to the second exemplifying embodiment described above and shown in Figures 3-4c, except that force applying device 11 of the friction damper 6, in addition to a spring element, further comprises an actuator 40. The actuator 40 is configured to control the force applied by the force applying device to the first plate-like member 8. The actuator 40 may for example be pneumatically or hydraulic controlled.

More specifically, the actuator 40 shown in Figure 7 is configured to apply a controllable force to the spring 14 (via the first washer 17, if present) and thereby also to the first plate-like member 8 (not visible in Figure 7 but shown in Figure 3). The actuator 40 may suitably be arranged between the spring 14 and the abutment 15 as shown in the figure. Thereby, the actuator 40 may be configured to control the force applied to the first plate-like member by changing the distance between the abutment 15 and the first plate-like member 8.

The actuator 40 may be connected to one of the first frame 2 and the second frame 3, for example via a pivot arrangement. One example of such a pivot arrangement is illustrated in the figure by a first component 48, firmly attached to the second frame 3, and a second component 49 pivotably connected to the first component 48 and furthermore connected to the actuator 40.

As described above, the vehicle arrangement according to the present disclosure comprises a first frame and a second frame (mounted to each other by a plurality of attachment arrangements) and a friction damper. Each of the first and second frames typically comprises two longitudinal members (configured to extend along the length of the vehicle) connected to each other by a plurality of cross members. The friction damper of the vehicle arrangement is suitably arranged at one of said two longitudinal members of the first and second frames. lt should here be noted that the vehicle arrangement preferably comprises a friction damper arranged at each of longitudinal members of the first and second frames, i.e. on both lateral sides of the vehicle, and preferably at laterally corresponding positions along the longitudinal extension of the longitudinal members. Moreover, the vehicle arrangement may comprise a plurality of the friction damper, these friction dampers may be separated from each other along the longitudinal extension of the longitudinal members of the first and second frames. Suitably, the friction dampers are arranged in the front portion of the vehicle arrangement, the front portion here intended to refer to the front portion of the vehicle comprising the vehicle arrangement.

Claims (13)

1.Claims A vehicle arrangement (10) comprising a first frame (2) and a second frame (3) mounted to each other by a plurality of attachment arrangements (4, 5), the vehicle arrangement (10) further comprising a friction damper (6) formed by: a first plate-like member (8) attached to the first frame (2) and comprising a first portion (8a) having a first friction surface (8b) arranged so as to face towards the second frame, a second friction surface (9b) arranged so as to abut the first friction surface (8b), said second friction surface (9b) formed by a surface arranged on the second frame (3) or by a surface of an optional second member (9) that is attached to the second frame (3), and a force applying device (11) configured to apply a force to the first plate-like member (8) in a direction towards the second friction surface (9b). The vehicle arrangement (10) according to claim 1, wherein the first plate-like member (8) comprises a first through-hole (12) arranged in the first portion (8a), the friction damper (6) further comprising a first elongated fastener (13) arranged so as to extend perpendicular to the second friction surface (9b) and through the first through-hole (12) of the first plate-like member (8), the first through-hole (12) having a diameter greater than the diameter of the first elongated fastener (13) so as to allow motion of the first plate-like member (8) relative to the first elongated fastener (13) in a plane parallel to the second friction surface (9b). The vehicle arrangement (10) according to claim 1 or 2, wherein the force applying device (11) comprises a spring element (14). The vehicle arrangement (10) according to claim 3, further comprising an abutment (15) arranged on the first elongated fastener (13), the spring element (14) being arranged so as to circumscribe the first elongated fastener (13), and wherein the spring element (14) is configured to apply the force to the first plate-like member (8) by applying a separating force between the abutment (14) and the first plate-like member (8). The vehicle arrangement (10) according to any one of the claims 2-4, wherein the spring element (14) is a coil spring.The vehicle arrangement (10) according to any one of the preceding claims, wherein the force applying device (11) comprises an actuator ( 40) configured to control the force applied to the first plate-like member (8). The vehicle arrangement (10) according to claim 4, wherein the force applying device (11) further comprises an actuator (40) configured to control the force applied to the first plate- like member (8) by changing the distance between the abutment (15) and the first plate-like member (8). The vehicle arrangement (10) according to any one of the preceding claims, wherein the plurality of attachment arrangements (4, 5) comprises a flexible attachment arrangement (5), and wherein the friction damper (6) is integrated with said flexible attachment arrangement (5) such that the first plate-like member (8) of the friction damper (6) is arranged between the second frame (3) and a first attachment member (20, 22) of the flexible attachment arrangement (5). The vehicle arrangement (10) according to claim 8, wherein the first attachment member (20, 22) comprises an opening (21, 23) through which the force applying device (11) extend. The vehicle arrangement (10) according to any one of claims 8 or 9, wherein the first attachment member is a support plate (20), the support plate (20) as well as the first plate-like member (8) being firmly attached to the first frame (2) by a first set of fastening means (19a, 19b), the flexible attachment arrangement (5) further comprising one or more support sleeves (33), each of said one or more support sleeves (33) attached to the second frame (3) and arranged so as to extend through a second through-hole (36) of the support plate (20), said second through-hole (36) having a diameter greater than the diameter of the support sleeve (33) extending therethrough to thereby allow a limited movement of the support plate (20) in a radial direction of the support sleeve (33). The vehicle arrangement (10) according to claim 10, wherein the flexible attachment arrangement (5) comprises a plurality of said support sleeves (33), each support sleeve (33) of the plurality of support sleeves (33) attached to the second frame (3) by a corresponding fastening means of a second set of fastening means (18a, 18b), andsaid second set of fastening means (18a, 18b), via the support s|eeves (33), firmly attaching the optional second member (9), if present, to the second frame (3). The vehicle arrangement (10) according to any one of c|aim 8 or 9, wherein the first attachment member is a first attachment bracket (22), the flexible attachment arrangement (5) further comprising a second attachment member in the form of a second attachment bracket (24), the first plate-like member (8) and the second attachment bracket (24) being firmly attached to the first frame (

2.) by a first set of fastening means (19a, 19b), the first attachment bracket (22) being firmly attached to the second frame (3) by a second set of fastening means (18a, 18b) via a plurality of spacers (38), and wherein the second attachment bracket (24) is flexibly attached to the first attachment bracket (22) via a fastening arrangement and at least one spring load (41). The vehicle arrangement (10) according to any one of the preceding claims, wherein one of the first and second frames (2, 3) is a chassis frame, and the other of the first and second frames (2,

3.) is a subframe. A vehicle (1) comprising the vehicle arrangement (10) according to any one of the preceding claims.