Abstract:
The hinge assembly of the present invention is a novel configuration that utilizes multiple arcuate shaped clevis elements. The configuration produces a compact, stable, and efficient means for transmitting an actuation force to retract or deploy one or more sections of a folding chute assembly utilized on transit concrete mixing vehicles.

Description:
CROSS-REFERENCED TO RELATED APPLICATIONS 
       [0001]    Not applicable 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable 
       TECHNICAL FIELD 
       [0003]    The invention relates generally to transit concrete mixing and delivery vehicles and, more particularly, to a multi-component linkage assembly for a concrete chute attached to a concrete mixer. The invention is particularly suited for manipulating a folding concrete chute from a stored (folded) configuration to a deployed configuration and back again. 
       BACKGROUND OF THE INVENTION 
       [0004]    It is common for transportable mixing units, like those employed on concrete trucks, to use a plurality of hinged chute sections, for movement between a retracted transport position and an extended discharge position, and for the transfer and discharge of concrete mix from a transport vehicle. It is well known in the art that a variety of hydraulically, pneumatically, or electrically driven assemblies are available to actuate the chute deployment and retraction process. Devices representative of the prior art are described in U.S. Pat. Nos. 4,458,800; 5,056,641; and 6,918,481 assigned to the same assignee as the present application. 
         [0005]    The vehicles themselves may be of a front or rear discharge type. In rear discharge vehicles the mechanism for discharging and delivering concrete from a mixing drum is positioned at the rear of the vehicle. And in a front discharge type, the mechanism for discharging and delivering concrete from a mixing drum is located above the vehicle&#39;s cab enclosure at the front of the vehicle. 
         [0006]    It is well known in the art that folding chute sections utilized for the discharge and delivery of concrete from the mixing drum are typically heavy and produce large stresses on the chute joints and actuator assemblies, particularly when loaded with concrete. The operation actuator and hinge assemblies experience significant resistive and torsional forces that result in rapid damaging wear and tear upon the parts. Additionally, designs commonly employed within the industry, while successful, are inefficient as to the delivery of functional forces from the actuator system to the point of deployment because of limitations in the hinge mechanisms. U.S. Pat. No. 3,774,741 (hereafter “the &#39;741 patent”) exemplifies this design. The embodiment depicted in FIGS. 1-7 of the &#39;741 patent shows a traditional single eyelet hinge design. Two chute segments are rotatably linked by a pair of hinges. The hinges comprise a pair of hinge eyelets, one eyelet on each side of each chute segment. These hinges utilize a single pivot bolt to rotatably fasten the chute segments. U.S. Pat. Nos. 4,498,568 and 4,458,800 also utilize this single eyelet hinge system. U.S. Pat. No. 3,930,567 exemplifies a slight modification to the single eyelet design where extended joint arms are employed. 
         [0007]    One common limitation with existing single eyelet hinge configurations occurs because a strong twisting force and motion results when the actuator operates as the actuator force is delivered through the joint to deploy or retract the chute segment. When actuator force is applied, inertial, gravitational, and frictional forces resist the desired rotational movement about the pivot. Delivery of the actuator force results in twisting forces at the weakest point, the rotational axis, within the system. The force will dissipate in all possible directions until the resistive forces are maximized and the movement about the hinges is the least resistive outlet for energy dissipation. The twisting forces place unwanted stress on the hinge components resulting in undue wear and tear on the components. This wear and tear on the chute joints results in excessive maintenance costs and inconvenient down time to repair the vehicle. 
       SUMMARY OF THE INVENTION 
       [0008]    An embodiment of the current invention depicts a folding chute assembly for a transit concrete mixing vehicle or the like. It comprises a pair of consecutive chute segments including an upper chute segment and a lower chute segment, the upper chute segment being pivotally attached in an end-to-end relationship with the lower chute segment. The upper chute segment and lower chute segment each have cooperatively mated ends to form a continuous channel for transfer of concrete mixture. It also contains a hinge arrangement fixedly attached to pivotally connect the upper chute segment with the lower chute segment at the cooperatively mated ends wherein said hinge provides for the deployment of the lower chute segment from a stowed configuration to a deployed configuration for the delivery of concrete mixture. The hinge arrangement comprises a plurality of stabilizing elements. The hinge may further comprise (1) a stabilizing clevis primary mounting bracket, fixedly attached to said upper chute segment, (2) an arcuate lever element, pivotally connected to the primary mounting bracket, (3) an arcuate clevis primary linkage element that is pivotally connected to the arcuate lever element, and (4) a secondary mounting bracket that is pivotally connected to the primary linkage element, pivotally connected to the primary mounting bracket, and fixedly attached to said lower chute segment. 
         [0009]    The current advance provides a folding delivery chute joint structure for concrete mixers that increases the strength of the joint and increases the efficient delivery of actuation energy through the joint, which in turn results in a component with reduced wear, lower maintenance costs, and less unpredictable maintenance down time. 
         [0010]    The hinge structure prevents tangential rotation about the joint pivot pins, thereby enabling transfer of operational energy more efficiently and effectively to deploy or retract the concrete delivery chute segments. 
         [0011]    The current invention applies multiple forked or clevis elements to create a balanced, stronger joint that resists torsional or twisting aspects and overcomes deficiencies of designs currently used in the art. A resulting multi-pronged design of the current linkage configuration provides a plurality of spaced pivot attachment points on opposing sides of connecting linkage components. This three-pronged design supports the attendant joints along the entire pivot axis in the deployment/retraction linkage system. The uniform support of the three-pronged arcuate design, derived from the extended support at these pivotal axis points, counteracts the torsional forces that have the tendency to induce an undesired rotation that is generally perpendicular to the direction of the desired hinge rotation. 
         [0012]    In addition, the three pronged design increases the number of contact points about the pivotal axis, which in turn increases the strength of the pivotal joint because the additional contact points provide greater stability and control of the pivot bolt or pin. The rotational resistive forces are deployed on either side of the rotation pivot point created by traditional designs and thereby prevent the pivot pin from undergoing perpendicular rotation about the axis point. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The foregoing and other advantages will become apparent upon examination of the description and the drawings contained herein, wherein: 
           [0014]      FIG. 1   a  is a side elevational view of a front discharge transit concrete mixing vehicle showing an embodiment of a type pertaining to the current invention; 
           [0015]      FIG. 1   b  is a side elevational view of the rear fragmentary portion of a rear discharge transit concrete mixing vehicle showing an embodiment of a distribution chute of a type pertaining to the current invention; 
           [0016]      FIG. 2   a  is an enlarged perspective view of an embodiment of a distribution chute of a type pertaining to the current invention; 
           [0017]      FIG. 2   b  is a side elevational view of a distribution chute of a type pertaining to the current invention with a lower chute segment folded in a stowed configuration; 
           [0018]      FIG. 2   c  is a side elevational view of a distribution chute of a type pertaining to the current invention showing the movement of the lower chute deployment configurations in phantom; 
           [0019]      FIG. 2   d  is a perspective view of a distribution chute of a type pertaining to the current invention with a lower chute segment in a deployed configuration; 
           [0020]      FIG. 3  is an exploded view of a distribution chute hinge in accordance with the current invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    Embodiments of the present invention are described herein with reference to  FIGS. 1 through 3 . The principles, the illustrative embodiments, and modes of operation for the present invention are described in the following specification. However, the invention, which is intended to be protected, is not to be construed as limited to the particular embodiment disclosed. Further, the embodiments described herein are meant to be regarded as illustrative rather than restrictive. Variations and changes may be made by others skilled in the art, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes, and equivalents that fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby. 
         [0022]    As illustrated in  FIGS. 1   a  and  1   b,  the embodiments of the current invention movably attach to a conventional transit concrete mixing truck which possesses a mixing drum  2  and a discharge spout  3  attached to and supported by a chassis  4  comprising a body frame member  5  and wheels  6 , having a conventional combination pivoting mount  7  and discharge hopper  8  for attaching a standard chute assembly  9  to the truck body frame member  5 . The embodiments include a hinge assembly generally at  10  for mechanically actuating and pivotally connecting an upper chute segment  12  to a lower chute segment  14  to produce the chute assembly  9 . 
         [0023]    Referring to  FIG. 2   a,  the illustrated hinge assembly  10  is a pin and clevis mechanism and includes four elements that are movably connected by a plurality of pivot joints. The elements may include a primary mounting bracket  20 , an arcuate lever element  25 , an arcuate primary linkage element  30 , and a secondary mounting bracket  35 . These elements are rotatably connected through a plurality of pivots as will be explained. 
         [0024]    Again referring to  FIG. 2   a,  the chute possesses an actuator assembly  39 . The actuator assembly  39 , preferably employing a double acting fluid (hydraulic or pneumatic) cylinder arrangement  40   a,  is provided to mechanically operate the hinge assembly  10  to pivot, deploy, or retract the pin and clevis arrangement to pivot the lower chute segment  14 . As seen in  FIG. 1   b,  the actuator assembly  39  may also employ an electrical mechanical actuator cylinder arrangement  40   b.  The cylinder arrangements  40   a  and  40   b  are coupled to the chute by actuator pivot pin  41  or other suitable pivotal connection attached to an actuator mounting bracket  42  which may be welded to the upper chute segment  12 . 
         [0025]    One aspect of the present invention is to provide a stronger hinge assembly  10  through which to effectuate an efficient transfer of energy from the cylinder arrangement  40   a  or  40   b  to the folding lower chute segment  14  for pivotal deployment or retraction of the lower chute segment  14 , as depicted in  FIG. 2   c.  A stronger hinge assembly is achieved by utilizing a clevis design with multiple joint members each possessing multiple pivot points. This configuration results in even distribution of actuation forces upon the joint and a joint with increased stability. 
         [0026]    A class of cement delivery chutes, to which the embodiments depicted in  FIGS. 1-2   d  pertain, contain two pivotally connected folding segments. As seen in  FIGS. 2   a - 2   d,  the upper chute segment  12  possesses a longitudinal direction that runs from a proximal end to a distal end.  FIGS. 1   a  and  1   b  show the proximal end of the upper chute segment  12  is designed to receive and direct mixed concrete, discharged from the mixing drum  2 , directed through the spout  3  and discharge hopper  8 . The proximal end of the upper chute segment  12  is attached and positioned at or near the discharge hopper  8 . The diameter of upper chute segment  12  may gradually narrow proceeding from the proximal end to the distal end.  FIGS. 2   a  and  2   d  illustrate upper chute segment  12  as being generally semi-circular in cross-sectional shape and forming a concave internal trough and a convex external wall. The semi-circular shape is designed to include a reinforcing member  43  that runs parallel to upper chute segment  12  and forms a first upper edge  44  of the upper chute segment  12 . 
         [0027]      FIGS. 2   a  and  2   d  show the lower chute segment  14  is pivotally attached at or near the distal end of the upper chute segment  12  by hinge assembly  10  and a second hinge assembly  48  of any known configuration. This second hinge assembly  48  may be of any adequately functional configuration and may also be a second hinge of the inventive configuration described herein. Lower chute segment  14  includes a proximal end and a distal end. The lower chute segment  14  is configured such that the cross-sectional shape of the proximal end cooperatively mates with the distal end of upper chute segment  12 , when lower chute segment  14  is unfolded and fully deployed. In this manner, a uniformly narrowing channel may be created over the entire length of the chute. This cooperative mating of segments provides for efficient, continuous transfer of concrete mixture from the raised opening in the mixing drum  2  to a convenient location for delivery. 
         [0028]    As seen in  FIGS. 2   a - 2   d,  a primary mounting bracket  20  is fixedly attached to upper chute segment  12  and is generally parallel to the longitudinal axis of the chute. Parallel mounting is necessary to allow proper pivotal movement of the chute segments and to compensate for a gradual narrowing of the cross-sectional diameter of the chute from the proximal end to the distal end of the chute segment. 
         [0029]    As seen in  FIG. 3 , embodiments of the current invention employ a generally “U”-shaped clevis member or primary mounting bracket  20 . The clevis or forked design greatly improves the strength and stability of the joint by providing support on both ends of the pivots associated with the primary mounting bracket  20 . This type of support is not found in prior linkage systems for folding delivery chute joint structures in concrete mixers, and the new configuration greatly reduces unwanted twisting motion in the pivot joint. 
         [0030]    The primary mounting bracket  20  comprises a proximal end and a distal end. The proximal direction of the mounting bracket corresponds to the proximal direction of the chute, and the distal end of the mounting bracket corresponds to the distal direction of the chute. 
         [0031]    As seen in  FIG. 3 , the primary mounting bracket  20  includes a solid weldment section  50  and a hinge section  52 . Hinge section  52  has two primary mounting bracket arm members  53 . Mounting bracket arm members  53  are spaced and so configured as to define a gap  54 . The weldment section  50  is fixed to the reinforcing member  43 , as seen in  FIG. 2   d,  at or near the first upper chute edge  44 . 
         [0032]    Primary mounting bracket  20 , specifically arm members  53 , is configured to function as the supporting framework for a plurality of generally transverse pivot joints  55 ,  58 . The primary mounting bracket  20  contains a plurality of corresponding opposed aligned opening pairs  59  and  60  to accommodate threaded pivot pins  61 ,  62  with corresponding threaded fasteners as nuts  63 ,  64 . The first axle or pivot pin  61  works in cooperation with opposed, aligned opening pair  59  to form a first pivot joint  55 . The second pivot pin  62  works in cooperation with the second opposed, aligned opening pair  60  to form the second pivot joint  58 . Each opening pair  59 ,  60  is arranged and so configured to create an axis that is substantially transverse to the chute axis and substantially parallel to a plane created by the top edges of the chute. 
         [0033]    As seen in  FIG. 2   c,  this configuration allows for the cooperative rotational movement of the two chute segments around the first pivot joint  55  to pivot between a stowed configuration and a deployed configuration. Pivot pins  61 ,  62  may be formed using any type of threaded bolt or the like that provides a solid, stable central shaft about which the joint elements may rotate. 
         [0034]    Opposed, aligned openings  60  accept a second pivot pin  62  to create a second pivot joint  58  that provides for rotatably mounting generally arcuate lever element  25 . The arcuate lever element  25  provides a leverage function in the linkage design, allowing for a compact hinge mechanism at the pivot joint  58 . The lever element  25  is a generally flat metal plate and includes a first or proximal opening  65  near the proximal end and a second distal opening  66  at or near the distal end. Opening  65  is positioned to align with opposed, aligned openings  60  in primary mounting bracket  20 . The arcuate lever element  25  and the arcuate primary linkage element  30  are rotatably connected by pivot pin  62  positioned within openings  60  and  65 . 
         [0035]    As generally seen in  FIGS. 2   a - 3 , the linkage assembly also possesses a generally arcuate primary linkage element  30 . As seen in  FIG. 3 , linkage element  30  possesses a proximal end and a distal end. The configuration of the proximal end defines the spacing body  69  of generally fork shaped primary linkage element  30 . The spacing body  69  configuration further defines a central element eyelet  67 . The distal end is formed by two spaced, generally parallel arcuate primary linkage arm members  68  which form a support framework for a plurality of generally transverse pivot joints  70  and  72  accommodated by a plurality of opposed, aligned openings  73 ,  74  to accomplish this function. 
         [0036]    Openings  73  accept a third threaded pivot pin  75  and corresponding threaded nut  76  to create pivot joint  70 . The distal end opening  66  of arcuate lever element  25  attaches to rotate relative to arcuate primary linkage element  30  at pivot joint  70 . 
         [0037]    The primary linkage element  30 , opening pair  74 , a forth threaded pivot pin  78 , with threaded nut  79  form pivot joint  72 , with an axis that is substantially transverse to the chute axis and substantially parallel to the plane created by the top edges of the chute. 
         [0038]    As seen in  FIGS. 2   a - 2   d  and  3 , the final element of the hinge assembly  10  is secondary mounting bracket  35 , which is a generally “L”-shaped single plate with a proximal end and a distal end. The distal end, comprising a weldment region  85 , is fixedly attached to lower chute segment  14  and is generally parallel to the longitudinal axis of the chute. Parallel mounting is necessary to allow proper pivotal movement of the chute segments and to compensate for a gradual narrowing of the cross-sectional diameter from the proximal end to the distal end of the chute segment. The proximal end, or foot portion of the “L”, possesses an approximately 90-degree angle and defines a hinge region  82 . 
         [0039]    A secondary mounting bracket, first opening  87  is defined at or near the proximal end of the secondary mounting bracket  35  and the 90-degree angle of the hinge region  82 . Opening  87  of the secondary mounting bracket  35  is aligned with opening pair  74  of linkage element  30  at pivot joint  72  for rotational attachment. 
         [0040]    At or near the proximal end of the secondary mounting bracket  35  is a second opening  89 , which resides in the hinge region  82 . The proximal end of the secondary mounting bracket  35  is configured to reside within the gap  54  of the primary mounting bracket  20 . The opening  89  of secondary mounting bracket  35  is aligned with the opposed, aligned opening pair  59  of primary mounting bracket  20 . Pivot pin  61  thereby rotatably fastens the primary mounting bracket  20  to the secondary mounting bracket  35 . This connection fully establishes the cooperative configuration between the upper chute segment  12  and lower chute segment  14  for the hinge assembly  10 . 
         [0041]    One final aspect of the current embodiment is the rotatable connection of the primary linkage element  30  to the fluid cylinder  40   a,  or electrical cylinder  40   b,  arrangement to provide a means for delivering an actuation force to the hinge assembly  10 . The actuator assembly  39  in the form of a double acting fluid (hydraulic or pneumatic) cylinder arrangement  40   a,  with a piston rod  92  is fixed to clevis member  91  as at  94 . The double acting fluid cylinder arrangement  40   a  may also be performed by an electrical mechanical cylinder actuator  40   b.  Clevis member  91  includes spaced arm members  95  with opposed, aligned openings  96 . The central eyelet  67  of element  30  is rotatably connected to clevis member  95 . The central eyelet  67  and opposed, aligned openings  96  are cooperatively positioned to work with a fifth threaded pivot pin  97  and corresponding threaded nut  98  to create a fifth pivot joint  99  to rotatably fasten the actuator assembly  39  to the arcuate primary linkage element  30 . 
         [0042]    This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use embodiments of the example as required. However, it is to be understood that the invention can be carried out by specifically different devices and that various modifications can be accomplished without departing from the scope of the invention itself.