Patent Publication Number: US-6341919-B1

Title: Threaded side bar inserter

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention. 
     The present invention relates generally to a side bar inserter, and more particularly, but not by way of limitation, to an apparatus for inserting a side bar having a bar portion and a flanged end in a side face of a concrete slab formed by a slip form paver. 
     2. Brief Description of the Related Art. 
     Roads and runways are constructed of large expanses of concrete pavement, and therefore, are generally comprised of several slabs of concrete formed adjacent one another. When forming one slab of concrete adjacent to another slab of concrete, the adjacent concrete slabs are typically tied together with a plurality of steel side bars (also known as tie bars) spanning between each of the adjacent slabs. The side bars are inserted into the side face of the initially formed concrete slab so that a portion of the side bars extend a distance from the side face of the concrete slab. The adjacent slab is then poured thereby encompassing the extended portion of the side bars. 
     When a slip form paver is used to form the concrete slab, the side bars are often inserted into the side face of the concrete slab as the concrete slab is being formed. Slip form pavers are self-propelled machines having spaced vertical side forms and a screed extending between the side forms. The screed is supported by a frame and screeds the concrete deposited on the road bed ahead of the advancing slip form paver. The pressure exerted on the concrete by the screed and the side forms is sufficient so that the contour of the concrete slab is maintained as the slip form paver continues to advance down the road bed. 
     Side bars have conventionally been straight metal rods having a length sufficient so that half the side bar extends into one concrete slab and the other half extends into the adjacent concrete slab. To this end, numerous devices have been proposed for use in conjunction with a slip form paver for inserting such side bars into the side face of a concrete slab. 
     However, a two piece side bar has been introduced in recent years. The two piece side bar includes a first section that is inserted into the initially formed concrete slab and a second section that is connected to the first section so as to extend from the initially formed concreted slab prior to forming the adjacent concrete slab. The first section has an open threaded end which is adapted to threadingly receive one end of the second section. The threaded open end of the first section is also provided with an outwardly extending flange which acts to limit the depth of insertion of the first section into the concrete slab to where the threaded opening is substantially flush with the side face of the concrete slab. 
     When employing the side bar inserters of the prior art to insert the first section, problems are encountered due to the existence of the flange of the first section. That is, the side bar inserters of the prior art are provided with a bar receiving chamber in which a straight side bar will lie flat and in turn be inserted into the concrete slab in a normal relation relative to the side face of the concrete slab. However, when the first section of the two piece side bar is placed in the bar receiving chamber, the flange causes the bar portion to lie at an angle with respect to the side face of the concrete slab. As a result, the first section will be inserted into the concrete slab at a downward angle which will result in the second section extending at an upward angle. 
     To this end, an apparatus is needed for inserting a side bar having a bar portion and a flanged end in a side face of a concrete slab formed by a slip form paver which will accommodate the flanged end and thus permit the bar portion to be disposed at a selected relationship relative to the side face of the concrete slab. It is to such an apparatus that the present invention is directed. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to an apparatus for inserting a side bar having a bar portion and a flanged end in a side face of a concrete slab formed by a slip form paver. The apparatus includes a frame having a side bar receiving chamber defining a travel path. A slide pin is extendable through at least a portion of the side bar receiving chamber so as to engage the side bar and cause the side bar to be driven from the side bar receiving chamber along the travel path. A guide member is connected to the frame and movable between a first position wherein the guide member is positioned to vertically support the bar portion of the side bar in a selected relationship with respect to the side face of the concrete slab and a second position wherein the guide member is retracted from the travel path of the side bar to permit the flanged end of the side bar to travel past the guide member along the travel path unimpeded by the guide member. 
     The features and advantages of the present invention will become apparent from the following detailed description when read in conjunction with the accompanying drawings and appended claims. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     FIG. 1 is a side elevational view of a side bar inserter constructed in accordance with the present invention shown mounted on a slip form paver. 
     FIG. 2 is a partially cutaway, side elevational view of a first section of a threaded side bar. 
     FIG. 3 is a perspective view of the side bar inserter of the present invention. 
     FIG. 4 is a partial cutaway, side elevational view of the guide flap assembly of the side bar inserter. 
     FIG. 5 is a partial cutaway, top plan view of the guide flap assembly of the side bar inserter. 
     FIGS. 6A-6C are side elevational views of the side bar inserter of the present invention illustrating the sequential operation of the side bar inserter during the process of inserting a threaded side bar into the side face of a concrete slab. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and more particularly to FIGS. 1 and 2, a threaded side bar inserter  10  (FIG. 1) constructed in accordance with the present invention is shown mounted on the side of a slip form paver  12 . The threaded side bar inserter  10  is used to insert a side bar  14  (FIG. 2) having a bar portion  16  and a flanged end  18  in a side face  20  of a concrete slab  22  formed by the slip form paver  12 . More specifically, the side bar  14  is a first section  24  of a two piece side bar. 
     As mentioned above, a two piece side bar has been introduced in recent years. The two piece side bar includes the first section  24  that is inserted into the side face  20  of the concrete slab  22  and a second section (not shown) that is connected to the first section  24  so as to extend from the concrete slab  22  prior to forming an adjacent concrete slab. As illustrated in FIG. 2, the first section  24  includes the bar portion  16  and the flanged end  18 . The first section  24  further has a threaded opening  26  which is adapted to threadingly receive one end of the second section (not shown). The flanged end  18  acts to limit the depth of insertion of the first section  24  into the concrete slab  22  to where the threaded opening  26  is substantially flush with the side face  20  of the concrete slab  22 . 
     Returning to FIG. 1, the slip form paver  12  is a self-propelled machine having spaced vertical side forms (not shown) and a screed (also not shown) extending between the side forms. The screed is supported by a frame  28  and screeds concrete deposited on a road bed  30  ahead of the advancing slip form paver  12 . The pressure exerted on the concrete by the screed and the side forms is sufficient so that the contour of the concrete slab  22  is maintained as the slip form paver  12  continues to advance down the road bed  30 . The slip form paver  12  also include an edger  32  which travels along the side face  20  of the concrete slab  22 . The edger  32  has a slot  33  which extends from the rear edge of the edger  32  towards the forward edge of the edger  32 . The slot  33  provides an opening through which the side bar  14  is inserted into the side face  20  of the concrete slab  22  as the slip form paver  12  advances down the road bed  30 . 
     Referring now to FIG. 3, the threaded side bar inserter  10  includes a frame assembly  40 , a bar guide assembly  42 , and a slide pin assembly  44 . The frame assembly  40  includes an elongated tray  46  having a first end  48 , a second end  50 . A guide tube  52  having a longitudinal slot  54  is secured in the tray  46  so as to define a side bar receiving chamber  56  which defines a travel path for the side bar  14 . The slot  54  is dimensioned to permit the side bar  14  to be loaded into the side bar receiving chamber  56  through the slot  54 . The slot  54  is provided with an enlarged section  57  for receiving the flanged end  18  of the side bar  14 . The frame assembly  40  further includes an upright bracket assembly  58  extending from the near the first end  48  of the tray  46 . The bracket assembly  58  supports the slide pin assembly  44 . 
     To connect the threaded side bar inserter  10  to the slip form paver  12 , the second end  50  of the tray  46  is pivotally connected to the edger  32  of the slip form paver  12  by a tray hinge  59 . The tray hinge  59  includes a first hinge member  60  attached to the bottom of the tray  46  (as best shown in FIG.  4 ), a pin  61  rotatably positioned within a tubular portion  60   a  of the first hinge member  60 , and a pair of brackets or lugs  62  which are rotatably disposed on the pin  61  and attachable to the edger  32  by welding or the like. The upright bracket assembly  58  is suspended from the slip form paver  12  with a chain assembly  63  extendible between the upper end of the upright bracket assembly  58  and a portion of the slip form paver  12 . 
     It will be appreciated by those of ordinary skill in the art that the threaded side bar inserter  10  can be attached to the slip form paver  12  in a variety of different ways other than that described above. For example, in addition to using the chain assembly  63  to support the upright bracket assembly  58 , the pin  78  may be extended and utilized to attach the threaded side bar inserter  10  to an adjustable boom assembly (not shown) connected to and extending from the slip form paver  12  whereby the threaded side bar inserter  10  is not attached directly to the edger  32 . 
     The slide pin assembly  44  includes a slide pin  64  and a guide flap depressor  65 . The slide pin  64  is disposed in the side bar receiving chamber  56  so as to be movable through the side bar receiving chamber  56  between a retracted position (FIG. 3) and an extended position (FIG.  6 C). The slide pin  64  has an engaging end  66  which is engageable with the flanged end  18  of the side bar  14  to cause the side bar  14  to be driven from the side bar receiving chamber  56  along the travel path defined by the side bar receiving chamber  56 . The engaging end  66  of the slide pin  64  includes a bolt  67  which is adjustable along the longitudinal axis of the slide pin  64  to adjust the depth of insertion of the side bar  14  into the concrete slab  22 . 
     The guide flap depressor  65  is a plate mounted to the slide pin  64  so that the guide flap depressor  65  travels in conjunction with the slide pin  64 . The function of the guide flap depressor  65  will be described in detail below. 
     The slide pin assembly  44  further includes a cylinder  68  for moving the slide pin  64  through the side bar receiving chamber  56  between the retracted position and the extended position. The cylinder  68  has one end pivotally attached to the bracket assembly  58  and another end pivotally attached to a portion a rocker arm  69 . The rocker arm  69  in turn has one end pivotally attached to a bracket  70  which is connected to the slide pin  64  and another end pivotally attached to one end of a link arm  71 . The other end of the link arm  71  is pivotally attached to the bracket assembly  58 . Upon extension of the cylinder  68  the slide pin  64  is caused to travel through the side bar receiving chamber  56  to the extended position and upon retraction of the cylinder  68  the slide pin  64  is caused to travel back through the side bar receiving chamber  56  to the retracted position. The cylinder  68  is preferably a hydraulic cylinder but it will be appreciated by those of ordinary skill in the art that other types of actuation, including pneumatic and electrical, as well as manual, can be employed. 
     It is desirable to insert the bar portion  16  of the side bar  14  into the side face  20  of the concrete slab  22  so that the bar portion  16  of the side bar  14  is in a substantially normal relationship to the side face  20  of the concrete slab  22  or some other selected relationship. Therefore, the bar guide assembly  42  is provided to compensate for the dimensional differences between the bar portion  16  and the flanged end  18  of the side bar  14 , and thus, support the bar portion  16  of the side bar  14  in a selected relationship relative to the side face  20  of the concrete slab  22 . At the same time, the bar guide assembly  42  is retractable so that the flanged end  18  of the side bar  14  may pass through the side bar receiving chamber  56  unimpeded by the bar guide assembly  42 . 
     As best shown in FIGS. 3-5, the bar guide assembly  42  comprises a guide flap  72  which has a bottom plate  73 , a pair of upright plates  74   a ,  74   b  extending from opposites sides of the bottom plate  73 , and a pair of slide plates  76   a ,  76   b  mounted on the upper end of the upright plates  74   a  and  74   b , respectively. Each of the upright plates  74   a ,  74   b  is configured to receive and be secured to a pin  78  extending transversely between the upright plates  74   a  and  74   b . The pin  78  is disposed through a tube  80  (illustrated in phantom in FIG. 5) which is attached to a lower surface of the tray  46  such that the guide flap  72  is rotatable relative to the tray  46  of the frame assembly  40 . 
     The bar guide assembly  42  further includes a guide member bracket  82  mounted to the bottom plate  73  of the guide flap  72  and a guide member  84  mounted to the guide member bracket  82 . The guide member  84  is provided with an opening  86  (FIG. 3) sized to slidingly support and guide the bar portion  16  of the side bar  14  and a slit  88  (FIGS. 3 and 5) to permit the guide member  84  to be selectively retracted or pulled away from the bar portion  16  of the side bar  14  in a manner to be discussed in greater detail below. As such, the guide member  84  is constructed of a pliable material, such as a rubber, that will permit the bar portion  16  of the side bar  14  to pass through the slit  88  upon the guide member  84  being retracted form the side bar  14 . Alternatively, the end of the guide member bracket  82  can be configured to have a substantially U-shaped slot sized to slidingly support the bar portion  16  of the side bar  14  if the bar portion  16  of the side bar  14  does not require an loop type guide. 
     The slide plates  76   a  and  76   b  are spaced apart a suitable distance to permit the bar portion  16  of the side bar  14  to be disposed into the side bar receiving chamber  56 . The slide plates  76   a  and  76   b  are further supported by a vertical brace  90 . Each of the slide plates  76   a  and  76   b  has an angled surface  91  (FIG. 4) which is engageable by the leading edge of the guide flap depressor  65  so as to cause the guide flap  72  to move from a first position (FIG. 4) wherein the guide member  84  is positioned to support the bar portion  16  of the side bar  14  in a selected relationship with respect to the side face  20  of the concrete slab  22  and a second position (FIG. 6C) wherein the guide member  84  is retracted from the travel path of the side bar  14  to permit the flanged end  18  of the side bar  14  to travel past the guide member  84  along the travel path unimpeded by the guide member  84  upon at least a portion of the bar portion  16  of the side bar  14  being inserted into the side face  20  of the concrete slab  22  such that the bar portion  16  is vertically supported by the concrete slab  22 . 
     The guide flap  72  is biased in the first position by a pair of extension springs  92 . Each of the extension springs  92  has one end attached to a loop  93  formed on the tray  46  and another end attached to a bolt  94  extending from the upright plate  74   a  and  74   b . The extension springs  92  extend over the tube  80 , as best shown in FIG. 4, so as to cause the guide flap  72  to be biased in the first position wherein the bottom plate  73  of the guide flap  72  engages the bottom of the tray  46 . 
     Operation 
     Referring now to FIGS. 6A-6C, the threaded side bar inserter  10  is attached to the slip form paver  12  so that the side bar receiving chamber  56  is aligned with the slot  33  of the edger  32  of the slip form paver  12  and positioned in a substantially normal relationship with respect to the edger  32 . A side bar, such as the side bar  14  described above, is loaded into the side bar receiving chamber  56  with the bar portion  16  supported by the guide member  84  of the guide flap  72 . The side bar  14  is manually loaded into the side bar receiving chamber  56 . However, it will be appreciated that it may be possible to automatically feed the side bar  14  from a magazine (not shown). 
     With the side bar  14  in the side bar receiving chamber  56 , the cylinder  68  is actuated so as to cause the cylinder  68  to move to the extended position thereby causing the slide pin  64  to move through the side bar receiving chamber  56  from the retracted position (FIG. 6A) to the extended position (FIG. 6C) so as to engage the flanged end  18  of the side bar  14  and cause the side bar  14  to be driven from the side bar receiving chamber  56  and into the side face  20  of the concrete slab  22 . As the slide pin  64  travels through the side bar receiving chamber  56  from the retracted position to the extended position, the guide flap  72  is caused to be moved from the first position (FIGS. 6A and 6B) wherein the guide member  84  supports the bar portion  16  of the side bar  14  in a substantially normal relationship with respect to the side face  20  of the concrete slab  22  when the flanged end  18  of the side bar  14  is positioned in the side bar receiving chamber  56  to the second position (FIG. 6C) wherein the guide member  84  is retracted from the travel path of the side bar  14  to permit the flanged end  18  of the side bar  14  to travel past the guide member  84  along the travel path unimpeded by the guide member  84 . 
     The guide flap  72  is caused to be rotated to the second position by the engagement of the guide flap depressor  65  with the slide plates  76   a  and  76   b  of the guide flap  72 . As shown in FIG. 6B, the guide flap depressor  65  initially engages the slide plates  76   a  and  76   b  only upon at least a portion of the bar portion  16  of the side bar  14  being inserted into the side face  20  of the concrete slab  22  such that the bar portion  16  is vertically supported by the concrete slab  22 . As the slide pin  64  continues to move to the extended position, the guide flap depressor  65  slidingly engages the angled surfaces  91  of the slide plates  76   a  and  76   b  causing the guide flap  72  and thus the guide member  84  to be rotated downwardly to the second position (FIG.  6 C). With the guide member  84  retracted from the travel path of the side bar  14 , the side bar  14  is driven into the side face  20  of the concrete slab  22  unimpeded by the guide member  84 . 
     Subsequent to the side bar  14  being driven into the concrete slab  22 , the cylinder  68  is actuated so as to cause the cylinder  68  to move to the retracted position thereby causing the slide pin  64  to move through the side bar receiving chamber  56  from the extended to the retracted position and thus disengaging the guide flap depressor  65  from the slide plates  76   a  and  76   b  of the guide flap  72  such that the guide flap  72  is caused to return to the first position ready to receive another side bar. 
     From the above description it is clear that the present invention is well adapted to carry out the objects and to attain the advantages mentioned herein as well as those inherent in the invention. While presently preferred embodiments of the invention have been described for purposes of this disclosure, it will be understood that numerous changes may be made which will readily suggest themselves to those skilled in the art and which are accomplished within the spirit of the invention disclosed and as defined in the appended claims.