Abstract:
A vehicle cab frame includes a base frame, with connection elements mounted on the base frame, as well as support elements mounted on the connection elements. Functional surfaces for linking attachment parts are formed on the support elements and the functional surfaces have a specified spatial orientation subject to tolerances. In order to improve the positioning accuracy of functional surfaces, the support elements are oriented and positioned relative to the connection elements so that tolerance deviations due to the construction of the base frame can be compensated by corresponding orientation and positioning of the support elements relative to the connection elements.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a vehicle cab frame. 
       BACKGROUND OF THE INVENTION 
       [0002]    It is known to provide many types of vehicles with cabs which include a cab frame. For example, construction vehicles or agricultural vehicles have cab frames with a support structure or a support frame constructed as a welded construction using steel-pipes. Such welded constructions pose the problem that the support frame is exposed to uncontrollable deformation or uncontrollable warping due to the introduction of heat because of heating during the welding process and also because of cooling afterwards, so that dimensional tolerances are often difficult to observe or cannot be observed, and finishing work of the already welded support frame is required so that the vehicle cabin attachment parts that are mounted on the support frame with a certain sensitivity to tolerances specific to the processing can be mounted with dimensional precision. Such attachment parts can represent inner and outer lining elements, doors, winds, seals, etc. For example, due to the warping of the support frame, problems can occur with respect to handling that is reliable during processing for the tolerance-sensitive functions to be performed by the support frame, such as, e.g., the provision of an exact positioning of the attachment point for a door hinge, a dimensionally precise adhesive surface geometry for the bonding of glazing, a dimensionally precise sealing surface for doors and plates or an exact positioning of the attachment point for a roof structure or for a cabin lining. 
       SUMMARY 
       [0003]    Accordingly, an object of this invention is to provide a vehicle frame to which vehicle cabin attachment parts can be mounted with dimensional precision. 
         [0004]    This and other objects are achieved by the present invention, wherein a vehicle cab frame is constructed so that the support elements can be oriented and positioned relative to the connection elements mounted on the base frame such that tolerance deviations due to a construction method (for example, welding) of the base frame can be compensated by the corresponding orientation and positioning of the support elements relative to the connection elements. The connection elements and the support elements are positioned on the base frame independent from the actual welding production of the base frame, so that the frame warping generated during the welding of the base frame can be optimally compensated by the positioning of the support elements. Here, the connection elements can be welded on the base frame at provided or specified positions, advantageously simultaneously, together with the support elements or can be mounted on this base frame in some other way. In this way, the support elements can be oriented exactly with respect to a specified spatial geometry (edge geometry or orientation of the functional surfaces of the support elements in a specified spatial geometry) and can be mounted with positional precision on the previously welded base frame. The production sequence named above can also be performed not simultaneously but instead sequentially as a function of the specified spatial geometry or component geometry. 
         [0005]    The base frame can comprise several posts, advantageously steel posts, welded with each other, wherein the base frame represents a solid base construction through which both static and also dynamic, safety-relevant forces on the vehicle can be absorbed. Thus, for example, the post thickness is dimensioned such that, if the vehicle rolls over, several times the weight of the vehicle can be absorbed by the base frame construction. 
         [0006]    The base frame could comprise posts, advantageously steel posts, formed as tubular posts. Tubular posts can have advantages in shaping in a bending process and/or in joining in a welding process (or a different joining process, for example, bonding) compared with other, for example, rectangular post shapes, because tubular posts are not sensitive to twisting due to their uniform outer surface, so that during the bending process and/or also during the joining of the posts, essentially no attention must be given to the orientation of the outer surface. A cylindrical outer surface of a tubular post, however, can have disadvantages compared with a flat outer side of a rectangular post for a tolerance-precise orientation, positioning, and/or attachment of components, if the outer surface is used directly as a reference and connection surface, which is why conventionally the use of tubular posts for constructions with tolerance-precise component positioning and component connections had been avoided. For a frame construction according to the invention, such aspects can be disregarded, so that for the construction of the base frame, both tubular posts, cylindrical or circular and also rectangular cross sections, could be used, because here the tolerance-precise orientation, positioning, and/or attachment of components is performed exclusively in combination of the connection elements with the support elements and one is not bound in the typical way to the form of the outer surface of the post. Also, the use of posts with mixed cross sections is not a problem, so that, in one construction, posts of different forms and different cross sections can be combined with each other easily. It should be noted that posts of other cross sections can also be used in the same way, for example, L-posts, I-posts, T-posts, U-posts, or also oval-shaped posts. 
         [0007]    The base frame can be formed, for example, as a base frame of a vehicle cabin, with the support elements being arranged on an outer side of the base frame. As already mentioned, a large part of the forces acting on the frame construction are absorbed by the base frame. The support elements and the connection elements take up only a very small portion, essentially only the dead weight of the outer parts mounted on them in the vehicle cabin, such as car body parts, linings, doors, panels, etc. Such a frame construction, however, is not limited to just use for vehicle cabins. 
         [0008]    The base frame comprises, with respect to the orientation of the vehicle cabin, front and/or rear posts extending vertically on which the support elements are mounted. In addition to a closed construction with a vehicle cabin roof, two front posts, and two rear posts, an open construction or a partially open construction of the vehicle cabin is also possible, so that the vehicle cabin has a cantilevered roof that is supported by only the rear or front posts. The use of a frame construction according to the invention as a so-called roll-over protection system (ROPS) is also conceivable. 
         [0009]    The support elements have functional surfaces that can be formed as adhesive surfaces, sealing surfaces, positioning surfaces, or door-hinge-link surfaces and are thus subject to a high positioning tolerance. Deviations that lie outside of the specified tolerance range can lead to leaks or functional interference in the activation of doors or windows. Furthermore, functional interference can also occur in adhesive surfaces, so that, for example, an adhesive connection is realized defectively. The same applies for sealing surfaces that do not satisfy a specified tolerance dimension. In addition, assembly problems can occur in series production. 
         [0010]    The support elements and/or the connection elements could be constructed as shaped sheet steel, wherein the material thickness of the support elements is smaller than that of the steel posts of the base frame. 
         [0011]    Therefore, because a smaller material thickness is to be processed, in particular, is to be connected to each other, lower quantities of thermal energy can be applied in a welding process, in order to weld the parts to each other. Therefore, the distortion generated during the welding is also reduced during the heating and cooling of the parts welded to each other. This results in higher dimensional accuracy and therefore also higher tolerance accuracy. Thus, frame distortion generated during the welded construction of the base frame can be compensated by the attachment of the connection and support elements or by their exact positioning, without additional, excessive distortion of the connection and support elements welded to each other leading to tolerance errors. 
         [0012]    The support elements are provided with openings or recesses through which the connection elements extend at least partially. The position of the support elements or the openings of the support elements can thus vary with respect to the connection elements. Thus, the support elements are advantageously oriented together with the connection elements if needed according to the specified spatial geometry, wherein the openings of the support elements are constructed such that a maximum tolerance deviation to be expected in the base frame can be compensated through corresponding positioning of the openings relative to the connection elements and are welded or connected to the connection elements in an additional step. The connection elements are used here as spacers between the base frame and support element. According to the frame distortion on the base frame, individual regions on the support element can be positioned differently close to or far from the corresponding base frame post, so that distance differences between the support frame and base frame can be set at several positions along a base frame post, wherein a tolerance compensation or a spacing correction is possible with respect to several degrees of freedom. 
         [0013]    The connection elements can be welded or also, for example, bonded on the base frame, wherein other attachment forms are also conceivable. In the same or similar way, the support elements could also be welded to the connection elements or bonded with these elements. 
         [0014]    The support elements arranged on a post can be constructed in one piece, so that they extend across the entire length of the post. Here, several connection elements are arranged distributed across the length of the posts that correspond, on the support elements, with openings distributed across the length of the support elements. It is also possible, however, to construct the support elements on a post in several parts. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a schematic side view of an agricultural vehicle; 
           [0016]      FIG. 2  is a schematic perspective view of a frame construction according to the invention for a vehicle cabin of a vehicle of  FIG. 1 ; 
           [0017]      FIG. 3  is a schematic perspective rear view of the frame construction of  FIG. 2  on a rear post; 
           [0018]      FIG. 4  is a schematic perspective side view of the frame construction of  FIG. 2  on the rear post of  FIG. 3 ; 
           [0019]      FIG. 5  is a schematic top view of the frame construction of  FIG. 2  on the rear post of  FIGS. 3 and 4 ; 
           [0020]      FIG. 6  is a perspective side view of the frame construction of  FIG. 2  on a front post; and 
           [0021]      FIG. 7  is a schematic top view of the frame construction of  FIG. 2  on the front post of  FIG. 6 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0022]    Referring to  FIG. 1 , an agricultural vehicle  10 , such as for example, a tractor or hauler, has a cabin  12  that is constructed as a frame  14 . The vehicle  10  could also be some other agricultural vehicles (e.g., harvesting machines, spraying machines, loaders, etc.) or a vehicle in the construction sector (e.g., wheel loaders, backhoes, diggers, etc.) or forestry equipment (e.g., pull-back machines). 
         [0023]    The frame  14  includes a base frame  16  that is welded together (see, in particular,  FIG. 2 ). The base frame includes two front posts  18 ,  20 , advantageously steel, extending essentially vertically, as well as two rear posts  22 ,  24 , advantageously steel, extending essentially vertically, wherein the posts  18 ,  20 ,  22 ,  24  were subjected to specified shaping in a preceding bending process. 
         [0024]    The posts  18 ,  20 ,  22 ,  24  are welded with posts  26  running longitudinal to the direction of travel of the vehicle  10  and with post  28 , advantageously steel posts, running perpendicular to the direction of travel of the vehicle  10 , which were likewise subjected to shaping by bending. Alternatively, the posts  18 ,  20 ,  22 ,  24 ,  26 ,  28  could also be bonded to each other. The thickness and dimensions of the posts  18 ,  20 ,  22 ,  24 ,  26 ,  28  are such that they can withstand loading that is caused by an accident and that can correspond to several times the weight of the vehicle. For example, if the vehicle rolls over, to a large extent it is guaranteed that the posts do not buckle. By means of an additional post  29  running perpendicular to the direction of travel of the vehicle  10  on a lower region of the frame  14  and a base plate  30 , the frame  14  is connected to a frame  31  of the vehicle  10 . With respect to a typical designation in vehicle construction for frame structures of car bodies and cabins, the posts  18 ,  20  are comparable to an A-pillar (front post) and the posts  22 ,  24  are comparable to a C-pillar (rear post), wherein, in the present example, the frame  14  has no middle B-pillars in this respect. 
         [0025]    The frame  14  further comprises connection elements  32 ,  34 ,  36 , wherein the connection elements  32 ,  34  are arranged on the rear posts  22 ,  24  and the connection elements  36  are arranged on the front posts  18 ,  20 . The arrangement and construction of the connection elements  32 ,  34  are especially clear with reference to  FIGS. 3-5  (as well as  FIG. 2 ) and the arrangement and construction of the connection elements  36  are to be seen with reference to  FIGS. 6 and 7  (as well as  FIG. 2 ), wherein the posts  22  arranged at the back left in the direction of travel in the example in  FIGS. 3-5  and the posts arranged at the front left in the direction of travel in the example in  FIGS. 6 and 7  are shown with respect to the frame  14 . 
         [0026]    The frame  14  further comprises support elements  38 ,  40 , wherein support elements  38  are arranged on the rear posts  22 ,  24  and the support elements  40  are arranged on the front posts  18 ,  20 . The arrangement and construction of the support elements  38  is clear with reference to  FIGS. 3-5  (as well as  FIG. 2 ) accordingly and the arrangement and construction of the support elements  40  are to be seen with reference to  FIGS. 6 and 7  (as well as  FIG. 2 ). 
         [0027]    Thus, the frame  14  comprises two embodiments that differ from each other for the arrangement and construction of the connection elements  32 ,  34 ,  36  and the support elements  38 ,  40  that are described in detail below. 
         [0028]    The connection element  32  is in the form of a flat steel bar or a flat steel sheet or a steel band (see cross section in  FIG. 5 ) and extends in the direction of its length along the length of an upper, outer region of the post  22 . The connection element  32  is oriented in the direction of its width essentially perpendicular to the direction of travel of the vehicle  10 , wherein the connection element  32  is welded or bonded along its longitudinal edge with the surface of the post  22  directed outward and lateral to the vehicle  10  with respect to the frame  14 . Optionally, notches or recesses  42  that are used as positioning aids for the elements  32 ,  38  relative to each other are provided on the longitudinal sides of the support element  38  and also the connection element  32 , in that these aids can be brought into engagement with each other. 
         [0029]    The other connection element  34  arranged on the rear post  22  is in the form of a steel sheet formed as an L-post in its width cross section with two legs  44 ,  46  arranged at approximately 90° to each other (see cross section in  FIG. 5 , wherein the angular dimensions are set to 90° only as an example and obviously could also be larger or smaller) and extend in the direction of its length along the length of the same upper and outer region of the post  22 , wherein one of the legs  44  is welded or bonded along its longitudinal edge with the surface of the post  22  directed outward and at the rear to the vehicle  10  with respect to the frame  14  such that the other leg  46  is oriented approximately at an angle of 35°-55° to the orientation of the connection element  32  (see cross-sectional drawing with angular details in  FIG. 5 , wherein the angular dimensions are set to 35°-55° only as an example and obviously could be larger or smaller). Optional notches or recesses  48  that are used as positioning aids could be provided on the longitudinal edge of the connection element  34  or the leg  44  welded or bonded with the post  22 , in that they can be brought into engagement with raised sections  50  that could be formed accordingly on the rear outer surface of the post  22 . 
         [0030]    As can be seen in  FIG. 5 , the support element  38  is formed as a steel post extending along the connection elements  32 ,  34  and has two legs  52 ,  54  that extend in the width direction and that are dimensioned with an opening angle of approximately 120° relative to each other (see cross-sectional view in  FIG. 5 , wherein the angular dimensions are set to 120° only as an example and obviously could also be larger or smaller). The longitudinal edge of the leg  54  is provided with flanging  56  at approximately 90° relative to the leg axis of the leg  54 . 
         [0031]    As is to be seen especially well in  FIG. 5 , the connection element  32  and the leg  46  of the connection element  34  form a positioning opening  58  that extends in the longitudinal direction of the upper, outer region of the post  22  and by means of which the support element  38  can be positioned and can be connected, advantageously welded or bonded, at the leg  52  with the leg  46  of the connection element  34  or at the leg  54  with the connection element  32 . 
         [0032]    Several functional surfaces  60  that are distributed across the length and on which, for example, a cabin door (not shown) or lining elements can be attached are formed on the support element  38 . 
         [0033]    The positioning opening  58  between the connection elements  32  and  34  is dimensioned such that the support element  38  can be oriented within the positioning opening  58 , so that existing warping of the base frame  16  or the total deviations relative to specified spatial geometry dimensions for the functional surfaces  60  that are formed on the support element  38  and that are formed as door-hinge links in the embodiment shown in  FIGS. 3-5  can be compensated by corresponding positioning of the support element  38 . The material thickness values of the connection elements  32 ,  34  and the support element  38  are clearly smaller than the wall thickness of the posts of the base frame  16 , so that when the support element  38  is welded with the connection elements  32 ,  34 , a smaller introduction of heat is required, wherein thermal warping of the connection elements  32 ,  34  and the support element  38  can be essentially avoided or can move within the permitted tolerances, so that, overall, the required spatial geometry dimensions for the functional surfaces  60  can be observed or achieved easily and precisely through corresponding positioning of the support element  38 . Alternatively, the connection elements  32 ,  34  could also be bonded to the support element  38 , so that otherwise no thermal warping occurs. 
         [0034]    An additional arrangement and orientation of connection elements  32 ,  34  and the support element  38  are found in a corresponding manner on the other rear post  24 . 
         [0035]    The connection elements  36  of the second embodiment shown in  FIGS. 6 and 7  are U-posts that are made from sheet steel and that are arranged on an outer region of the posts  18 ,  20  spaced apart from each other along the length of the posts  18 ,  20  and welded or bonded with the posts. The connection elements  36  are arranged such that the legs of the u-shaped connection elements  36  are directed outward and oppose each other in the horizontal direction, wherein the orientation is selected such that the legs extend approximately along the bisecting ling of an angle between the front and side surfaces of the vehicle cabin  12 , that is, approximately enclosing an angle of 135° with the front or side or side surface (see angular details in  FIG. 7 , wherein the angular dimensions are set to 135° only as an example and obviously could also be larger or smaller). 
         [0036]    As is to be seen in  FIGS. 6 and 7 , the support element  40  is constructed as a steel post extending in its length along the post  18  and has two legs  62 ,  64  that extend in the width direction and that stand at an opening angle of approximately 90° relative to each other. (See  FIG. 7 , wherein the angular dimensions are set at 90° only as an example and obviously could also be larger or smaller). The longitudinal edge of the leg  62  is provided with flanging at approximately 90° relative to the leg axis of the leg  62 . 
         [0037]    Along the length of the support element  40  there are oval-shaped positioning openings  66  between the legs  62 ,  64 , that is, in the corner region of the support element  40  or in the region in which the legs  62 ,  64  contact each other, wherein these openings correspond in number and arrangement to those of the connection elements  36 . The positioning openings  66  have a width diameter that corresponds approximately to the outer distance of the two legs of the connection elements  36 , so that the legs of the connection elements  36  can extend through the positioning openings  66 . 
         [0038]    The support element  40  is positioned such that the legs of the connection elements  36  are brought into engagement with the positioning openings  66 , wherein according to the orientation of the support element  40 , the legs can project at different lengths through the positioning opening. According to a tolerance-precise orientation and arrangement of the support element  40  at the edge of the positioning openings  66 , the legs of the connection elements  36  are connected, advantageously welded or bonded to the support element  40 . 
         [0039]    On the support element  40 , there are functional surfaces  68  extending along the legs  62 ,  64  in the longitudinal direction of the support element  40  in the form of an adhesive surface and/or sealing surface on which glazing (not shown) can be bonded for the vehicle cabin  12  or that can be used as the sealing surface for a door seal of a cabin door (not shown). 
         [0040]    The positioning openings  66  as well as the form and length of the legs of the connection elements  36  are dimensioned such that the support element  40 , first, can be oriented and, second, it is guaranteed that after orienting the support element  40 , the legs of the connection elements  36  can still be connected to the edge of the positioning openings  66 . The orientation is realized such that existing warping of the base frame  16  or total deviations relative to specified spatial geometry dimensions for the functional surfaces  66  that are formed on the support element  40  and that are constructed as adhesive and/or sealing surfaces in the embodiment shown in  FIGS. 6 and 7  can be compensated by the corresponding positioning of the support element  40 . The material thickness values of the connection elements  36  and the support element  40  are here significantly smaller than the wall thickness values of the posts of the base frame  16 , so that, when the support element  40  is welded with the connection elements  36 , a smaller introduction of heat is required, wherein thermal warping of the connection parts  36  and the support element  40  can be avoided or can move within permitted tolerances, so that overall the required spatial geometry measures for the functional surfaces  66  can be maintained or achieved easily and precisely through corresponding positioning of the support element  40 . Alternatively, the connection elements  36  can also be bonded with the support element  40 , so that no thermal warping otherwise occurs. 
         [0041]    An additional arrangement and orientation of connection elements  36  and the support element  40  are found in a corresponding manner on the other front post  20 . 
         [0042]    Even if the invention was described merely with reference to two embodiments, in the light of the preceding description as well as the drawings, many different types of alternatives, modifications, and variants that fall under the present invention present themselves for someone skilled in the art. For example, the connection elements  32 ,  34 ,  36  or also the support elements  38 ,  40  could be shaped differently and could be connected to each other in different ways. The positioning openings  58 ,  66  and connection points can be supported at different positions. Furthermore, the support elements  38 ,  40 , as well as the connection elements  32 ,  34 , could also be formed in multiple parts, which is different than as shown in the example here. The posts  18 ,  20 ,  22 ,  24  (A-pillar and C-pillar) formed as cylindrical tubular posts in the frame  14  could also be formed as differently shaped tubular posts or even as open posts (e.g., as I-posts, T-posts, L-posts, U-posts, etc.). 
         [0043]    While the present invention has been described in conjunction with a specific embodiment, it is understood that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, this invention is intended to embrace all such alternatives, modifications and variations which fall within the spirit and scope of the appended claims.