Abstract:
A spreading apparatus is provided for spreading flowable materials such as adhesives and/or sealants on a surface such as a floor and/or a wall. The apparatus has a pad retainer for retaining a removable spreader pad and a reservoir chamber for flowable material pivotally attached to the pad retainer to permit pivoting of the reservoir chamber frontwards and backwards. The spreader pad comprises an elongated resilient foam member sufficiently thick to fit within and frictionally engage the pad retainer, and sufficiently high to extend below the pad retainer so that the spreader pad rather than the pad retainer contacts the surface when the spreader pad is retained by the pad retainer.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation-in-part of U.S. patent application Ser. No. 10/883,759 filed on Jul. 6, 2004. 

   FIELD OF THE INVENTION 
   This invention relates to spreading apparatuses for flowable materials, in particular to spreading apparatuses for spreading flowable adhesives and/or sealants on a surface. This invention also relates to spreader pads for the spreading apparatuses. 
   BACKGROUND OF THE INVENTION 
   A number of service industries in which a decorative or protective finish is applied to a surface employ an adhesive and/or sealant for that purpose. The adhesive and/or sealant must be spread uniformly as a thin coating on the surface. A particular industry with such a requirement is the installation of coverings on floors and/or walls. Coverings may be, for example, carpet, sheet plastic (e.g. vinyl), plastic tiles, ceramic tiles, composite strips and wood strips. 
   Adhesives and sealants are generally supplied in a variety of containers of the type also generally used for paints. Thus, small quantities of a liter or part liter are supplied in metal cans with press-on lids, while larger quantities, e.g. 20 or 40 liters, are supplied in small plastic drums with snap-on lids. Irrespective of the size of the surface that is to be coated, the usual method of application is for a quantity of the material to be poured onto the surface, if it is sufficiently easily flowable, or if too viscous to be poured easily, for small quantities to be scooped from the container and dumped on the surface. It is then spread uniformly by the operator, kneeling when the surface is a floor, employing for the purpose a metal or plastics hand tool of approximately rectangular shape, usually about 20 cm (8 ins) in width, the longer straight edge which engages the floor being toothed or serrated in a regular pattern so as to provide a row of uniform-size, uniformly-spaced gaps whereby corresponding uniform-size, uniformly parallel spaced lines of the adhesive are formed on the surface as the tool is dragged over it, the surplus material being pressed ahead of the tool and escaping around the edges. Such operations are labour-intensive and also tend to be somewhat messy unless the operator is particularly careful, especially as the container is emptied, when it becomes more difficult to extract the remaining material therefrom. 
   To mitigate against the problems in the art, there have been developed manually operable spreading apparatuses to assist in spreading flowable materials on to a surface. Such apparatuses are disclosed in U.S. Pat. No. 5,937,628 issued Aug. 17, 1999 and U.S. Pat. No. 6,325,563 issued Dec. 4, 2001, both in the name of William Matechuk. While these apparatuses are an improvement over the labour-intensive methods described above, there still remains a need for a spreading apparatus with improved spreading characteristics and improved ease of use. 
   SUMMARY OF THE INVENTION 
   In a first aspect of the invention, there is provided a spreading apparatus comprising: a pad retaining means for retaining a removable spreader pad for spreading a flowable material on a surface, the pad retaining means having a width over which the spreading pad spreads the flowable material; a reservoir chamber for flowable material comprising a front, a back and a bottom, the reservoir chamber pivotally attached to the pad retaining means to permit pivoting of the reservoir chamber frontwards and backwards, the reservoir chamber further comprising an adjustable gate through which the flowable material may exit the reservoir chamber when the gate is open, the gate proximal the bottom of the reservoir chamber and complementary to the width of the pad retaining means; and, a handle attached to and extending from the reservoir chamber. 
   In a second aspect of the invention, there is provided a spreading apparatus comprising: a pad retaining means for retaining a removable spreader pad for spreading a flowable material on a surface; a reservoir chamber for flowable material comprising an adjustable gate through which the flowable material may exit the reservoir chamber when the gate is open; a hollow handle connected to either or both of the pad retaining means and the reservoir chamber; and, a gate opening means attached to the handle, the gate opening means comprising an actuator and a cable, one end of the cable connected to the actuator and another end of the cable connected to the gate, the cable being housed within the hollow handle. 
   In a third aspect of the invention, there is provided a spreading apparatus comprising: a pad retaining means for retaining a removable spreader pad for spreading a flowable material on a surface; a reservoir chamber for flowable material attached to the pad retaining means, the reservoir chamber comprising an adjustable gate through which the flowable material may exit the reservoir chamber when the gate is open; and a handle pivotally attached to and extending from the reservoir chamber. 
   There is further provided a system comprising: a spreading apparatus as described above; a removable spreader pad for spreading the flowable material on the surface, the spreader pad removably retained by the pad retaining means by frictional engagement of the spreader pad with the pad retaining means; and, a container containing the flowable material, the container adapted to be housed in the reservoir chamber comprising an adjustable gate and adapted to cooperate with the gate to permit the flowable material to exit the container and the reservoir chamber when the gate is open. 
   There is yet further provided a spreader pad for use with a spreading apparatus as described above, the pad comprising an elongated resilient foam member sufficiently thick to fit within and frictionally engage the pad retaining means of the spreading apparatus, and sufficiently high to extend below the pad retaining means so that the spreader pad rather than the pad retaining means contacts the surface when the spreader pad is retained by the pad retaining means. 
   The reservoir chamber is a space in which a supply of flowable material may be stored in the spreading apparatus. Flowable material may be placed directly in the chamber, however, for cleanliness and ease of use, it is preferred that the flowable material be contained within a separate container and the container housed in the reservoir chamber. The container may be a bag or a cartridge or any other suitable container for the flowable material, which may be housed in the reservoir chamber. 
   The reservoir chamber comprises means through which the flowable material may be loaded into it, for example, an open top or a door in the chamber. In a preferred embodiment, the reservoir chamber is fully enclosed but may have a movable or removable front door or panel. In a particularly preferred embodiment, a front panel is pivotally secured to the reservoir chamber along the bottom of the panel so that it may fold down for easy access to the reservoir chamber. This facilitates loading containers of flowable material into the reservoir chamber. To prevent unwanted opening of the front panel, the panel may be releasably secured to the reservoir chamber by any suitable means, for example, screws, latches, clips, etc. Screws are preferred as they provide a more secure closure to resist pressure from the flowable material inside the reservoir chamber. 
   In order to spread flowable material on to a surface, the flowable material must be able to flow out of the reservoir chamber. In this respect, the reservoir chamber is provided with an adjustable gate. The gate may be closed or opened prevent or permit dispensing of the flowable material from the reservoir chamber. Preferably, the gate is proximal the bottom of the reservoir chamber, which facilitates emptying of the reservoir chamber and permits better control over where the flowable material is dispensed on the surface. Preferably, the gate is complementary to the width of the pad retaining means, which permits dispensing of the flowable material over a wider swath resulting in more uniform coverage of a larger area and reducing the extent to which the spreading apparatus must be manipulated to spread an even coating thickness over said area. In such an arrangement, when the gate is open there is an opening in the reservoir chamber which spans substantially the width of the spreader pad. Flowable material is thereby dispensed along substantially the entire width of the spreader pad and the operator only has to pass the spreader pad a minimal number of times through the flowable material to obtain uniform spreading of the flowable material over the width of the spreader pad. 
   The gate may operate on any suitable principle. For example, the gate may pivot or slide away from an opening in the reservoir chamber. Preferably, the gate is pivotally attached to the reservoir chamber. The gate is preferably closed unless the operator actively opens the gate. The gate may be retained in a closed position by biasing means, which biases the gate towards the closed position. To ensure complete closure of the gate, a strong biasing force is desirable. Opening the gate is accomplished by applying a force to the gate which acts against the biasing force applied by the biasing means. The gate may be opened and enclosed with a gate opening means. In one embodiment, the gate opening means comprises an actuator and a cable, one end of the cable connected to the actuator and another end of the cable connected to the gate. Any suitable actuator, for example, a lever or a wheel and crank, may be used. The actuator is preferably selectively lockable so that the operator could lock the gate in an open position if desired. Locking the gate in an open position especially facilitates loading and unloading containers of flowable material in the reservoir chamber. 
   In the case where flowable material is loaded directly into the reservoir chamber, opening and closing the gate will automatically control dispensing. Where a container of flowable material is housed in the reservoir chamber, the container must cooperate with the gate to permit dispensing of the flowable material. For example, when the flowable material is contained within a bag, for example a plastic bag, an edge of the bag may be inserted through the gate so that a portion of the bag protrudes from the gate. Slitting or cutting away the edge of the bag permits the flowable material to flow and closing the gate results in pinching the protruding portion so that flowable material is prevented from flowing. In another embodiment, a cartridge may be equipped with a flexible seal along one edge with is inserted through the gate in a similar manner as the bag. Flowable material may be dispensed from the reservoir chamber by any suitable means, for example, by gravity or by a powered mechanism (human or otherwise) such as a plunger, a collapsing plate, a roller or pressurized fluid (e.g. air). 
   In the spreading apparatus, the reservoir chamber is preferably attached to the pad retaining means. More preferably, the reservoir chamber is pivotally attached to the pad retaining means to permit pivoting of the reservoir chamber frontwards and backwards. Such a configuration facilitates keeping the pad retaining means parallel to the surface thereby ensuring that the pad is always in full contact with the surface. This leads to more uniform spreading of the flowable material and accommodates operators of various heights. 
   The pad retaining means retains the spreader pad in a removable fashion. Thus, the pad may be removed and replaced without replacing the pad retaining means or the spreading apparatus. Preferably, retention of the spreader pad is accomplished without the use of springs and/or clips nor any other ancillary element requiring operator manipulation. In this way, the pad may be removed and replaced more easily and the spreading apparatus is less complicated to build and maintain. 
   In a first embodiment, the spreader pad is retained by frictional engagement of the pad within the pad retaining means. The pad retaining means may comprise a tight tolerance channel having two walls between which the spreader pad is retained by frictional engagement of the pad with the inside surfaces of the two walls. The channel may be closed at the top to prevent the pad from slipping too far up between the walls. Part of the spreader pad extends below the pad retaining means so that the spreader pad rather than the pad retaining means contacts the surface. Each or either end of the channel may be further extended at a right angle to form an U-shaped or an L-shaped channel. In particular, a U-shaped channel with a corresponding U-shaped spreader pad helps keep flowable material confined to the region behind the spreader pad when the flowable material is dispensed from the gate. In this embodiment, the spreader pad may comprise an elongated resilient foam member sufficiently thick to fit between and frictionally engage the walls of the channel, and sufficiently high to extend below the walls of the channel. 
   In a second embodiment of the spreader pad, the pad as described above is thicker than can be forced between the channel walls but comprises a groove separating an inner part from an outer part of the pad. The inner part is sufficiently thick to fit between and frictionally engage the channel walls and the outer part covers an outside surface of a channel wall, which fits within the groove. The spreader pad may comprise one groove to accommodate one wall or two grooves to accommodate both walls. In this way, the spreader pad completely protects the walls of pad retaining means from the flowable material being spread so that little or no clean-up of the pad retaining means is necessary. 
   In a third embodiment of the spreader pad, a pad similar to the first embodiment of the spreader pad may further comprise a beveled bottom. Preferably, the bottom is beveled so that the outside front face of the pad is less wide than the inside face. Beveling the bottom of the pad provides for better scraping action when pulling the spreading apparatus toward the operator and less build or pooling when pushing the spreading apparatus away from the operator. This leads to more even distribution of the flowable material on the surface. 
   In a fourth embodiment of the spreader pad, a pad similar to the first embodiment of the spreader pad may further comprise a serrated spreader blade mounted at a bottom edge of the pad, preferably the bottom inside edge. The serrated blade helps impart a pattern to the flowable material on the surface providing more effective contact between the flowable material and a covering being applied to the surface thereby leading to better adhesion. For further improvement in spreading performance, the blade may comprise one or more slits to impart greater flexibility to the spreader blade. The blade may be mounted to the pad by any suitable means, for example adhesives, bolts and/or engaged within grooves in the pad. Preferably, the blade is glued to the pad. More preferably, the blade is both glued to the pad and engaged within grooves in the pad. The blade may be made of any suitable hard material, for example plastics, metals, etc. 
   A spreader pad combining beveling as described above and a serrated spreader blade as described above provides for even better spreading performance. 
   The spreading apparatus also comprises a handle. The handle is preferably attached to and extends from the reservoir chamber, i.e. the handle is preferably not attached directly to the pad retaining means. The handle is preferably pivotally attached to the reservoir chamber so that the handle can pivot from side to side to facilitate spreading flowable material in corners and to more easily follow uneven contours of the surface. The handle is preferably curved near the top for greater ease of use. 
   The handle is preferably hollow, both to reduce weight and to provide a housing for the cable associated with the gate opening means. For ease of use, the actuator for the gate opening means is preferably secured to the handle where the operator can easily activate the gate with his hand, for example the actuator may be secured to an underside of the handle where the actuator can be activated by gripping. In such a case, the cable must run from the gate, up the handle to the actuator. By housing the cable inside the handle, the cable is out of the way and is protected from damage due to operator handling and errant flowable material. 
   The handle may also comprise an adjustable side grip. The side grip may be adjusted up or down to accommodate the operator&#39;s height as well as his arm length. The side grip may also be adjusted from side to side to accommodate a right or left handed operator. 
   The spreading apparatus may be made of any suitable material, for example, metal (e.g. galvanized steel, aluminized steel), high strength plastic (e.g. high density polyethylene, polypropylene), etc. Preferably, the spreading apparatus is made of a material or materials to which the flowable material does not readily stick. Typically, a metal or metals provides a good balance of machinability, cost and maintainability. The front panel of the reservoir chamber is preferably transparent to permit ready determination of the amount of flowable material remaining in the reservoir chamber. The gate preferably comprises a lining of “no stick” material, for example a polyfluorinated hydrocarbon such as Teflon™. 
   The spreading apparatus of the present invention may be used to spread any flowable material. The flowable material is preferably an adhesive and/or sealant for the installation of coverings on surfaces such as floors and walls. Coverings may be, for example, carpet, sheet plastic (e.g. vinyl), plastic tiles, ceramic tiles, composite strips and wood strips. 
   The spreading apparatus of the present invention advantageously provides improved spreading of flowable material on a surface. Flowable material may be spread more uniformly and over a greater area. Wastage of flowable material may be reduced. The apparatus may be easier to use, facilitating the loading of flowable material, facilitating spreader pad replacement, providing better access to corners, accommodating the height of different operators and accommodating both right handed and left handed operators. The apparatus is easier to keep clean and to maintain. 
   Further features of the invention will be described or will become apparent in the course of the following detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the invention may be more clearly understood, embodiments thereof will now be described in detail by way of example, with reference to the accompanying drawings, in which: 
       FIG. 1  is a perspective view of a spreading apparatus of the present invention; 
       FIG. 2  is a side view of the spreading apparatus of  FIG. 1 ; 
       FIG. 3  is a front view of the spreading apparatus of  FIG. 1 ; 
       FIG. 4  is a back view of the spreading apparatus of  FIG. 1 ; 
       FIG. 5  is a bottom view of the spreading apparatus of  FIG. 1 ; 
       FIG. 6  is an enlarged side sectional view at the bottom of the spreading apparatus of  FIG. 1 ; 
       FIG. 7  is an enlarged side view at the bottom of the spreading apparatus of  FIG. 1 ; 
       FIG. 8  is an enlarged back view near the bottom of the spreading apparatus of  FIG. 1 ; 
       FIG. 9A  is a perspective view of one embodiment of a spreader pad of the present invention; 
       FIG. 9B  is a perspective view of another embodiment of a spreader pad of the present invention; 
       FIG. 10A  is a perspective view of yet another embodiment of a spreader pad of the present invention; 
       FIG. 10B  is a side cross-sectional view of the spreader pad of  FIG. 10A ; and, 
       FIG. 10C  is a bottom view of the spreader pad of  FIG. 10A . 
   

   DESCRIPTION OF PREFERRED EMBODIMENTS 
   Referring to  FIGS. 1–8 , an embodiment of a spreading apparatus of the present invention is illustrated. A reservoir chamber  1  in the shape of a rectangular prism having a top face, a bottom face, a front face, a back face and two side faces is pivotally attached to a U-shaped pad retaining means  3  by means of two bolts  5 . Only one of the two bolts  5  is shown, the other bolt corresponding in position to the one bolt but located on the other side. As best seen in  FIGS. 5 and 6 , the U-shaped pad retaining means  3  comprises a tight tolerance channel having two arms each arm extending at right angles from each end of a cross-member. A U-shaped foam spreader pad  7  is inserted in the channel and is held in place by frictional engagement of the pad within the channel of the pad retaining means  3 . 
   The front face of the reservoir chamber  1  is a transparent door  9  hinged at the bottom by a door hinge  11  running the width of the reservoir chamber (see  FIGS. 5 ,  6  and  7  in particular). The transparent door  9  is secured to the reservoir chamber  1  proximal the top of the reservoir chamber by two screws  13 . 
   A tubular hollow handle  15  having a top and a bottom is pivotally attached to the back face of and extends upward from the reservoir chamber  1 . A single bolt  17  at the bottom of the handle  15  and proximal the bottom of the reservoir chamber  1  attaches the handle to the reservoir chamber and provides the point at which the handle pivots. The handle is curved proximal the top and terminates in a foam hand grip  19 . An adjustable side grip  21  is secured to the handle  15  by a clamp  23  and may be adjusted left, right, up or down. In order to adjust the side grip  21 , the clamp  23  may be loosened and tightened by rotating the side grip  21  about the longitudinal axis of threaded pin  25  which is perpendicular to the handle  15 . A grip lever  27  is mounted to the handle  15  on the underside and at the top of the handle. A cable  26  extends from the grip lever  27  to an adjustable gate  29  located on the reservoir chamber  1 . Operation of the gate  29  is explained below. A lock  31  is located on the grip lever  27  for locking the grip lever in a depressed position (i.e. when the gate  29  is open). 
   As best seen in  FIG. 2 , pivoting of the reservoir chamber  1  on the bolts  5  permits backward and frontward pivoting of the reservoir chamber  1  (and the handle  15 ) while allowing the pad retaining means  3  to remain parallel to the surface and allowing the spreader pad  7  to remain in continuous contact with the surface (e.g. the floor) over the full spreading area of the pad.  FIG. 2  illustrates two possible positions of the reservoir chamber  1  and the handle  15  in relation to the pad retaining means  3 . One of the positions is illustrated in broken lines. Thus, the apparatus is efficiently utilizable by a person of any height. 
   As best seen in  FIGS. 3 and 4 , pivoting of the handle  15  on the bolt  17  permits side-to-side pivoting of the handle on the reservoir chamber  1  while allowing the reservoir chamber  1  and the pad retaining means  3  to remain in position.  FIG. 3  illustrates three possible positions of the handle  15  in relation to the reservoir chamber  1 . Two of the positions (a left position and a right position) are illustrated in broken lines. Thus, an operator can efficiently spread adhesive into corners. The handle  15  is provided with a plastic spacer  33  (see  FIG. 2 ) attached to and located part way up the handle to maintain a gap between the handle  15  and the back of the reservoir chamber  1 . The handle  15  is prevented from pivoting too far to either side by stops  35 , which stop the spacer  33  when the handle  15  is pivoted to a side. As an alternative embodiment, the spacer may cooperate with an arcuate groove cut into the back of the reservoir chamber with the ends of the groove acting as the stops. 
   As best seen in  FIGS. 4 and 5 , the adjustable gate  29  is located along the bottom back edge of the reservoir chamber  1  and extends substantially the entire width of the reservoir chamber. Since the reservoir chamber  1  is located substantially within the entire inside distance between the two arms of the pad retaining means  3 , it can be seen that the adjustable gate  29  is complementary to the width of the pad retaining means  3 . 
   As best seen especially in  FIGS. 5 ,  6  and  7 , the adjustable gate  29  comprises a bracket  37  traversing the width of the reservoir chamber. The bracket comprises a first flange and a second flange forming a right angle. The first flange is attached to one panel of a panel hinge  39 , while another panel of the panel hinge  39  is attached to the back face of the reservoir chamber  1 . The second flange of the bracket  37  covers an opening  41  formed along the bottom of the back face of the reservoir chamber  1  over substantially the entire width of the reservoir chamber. Pivoting about the hinge pin of the panel hinge  39  permits movement of the second flange away from the opening  41  resulting in opening of the gate  29 . The second flange of the bracket  37  is biased towards the opening  41  and held in place over the opening by a pair of springs  43  located at each end of the bracket  37 . In this manner, the adjustable gate  29  is normally closed. Each of the springs  43  is attached to the second flange of the bracket  37  and a side face of the reservoir chamber  1 . 
   As indicated above, a cable  26  extends from the grip lever  27  to the adjustable gate  29 . The cable  26  is housed within the hollow handle  15  from substantially the grip lever  27  to the bottom of the handle. The cable  26  comprises an outer sheath  45 , typically made of a plastic or rubber, and an inner wire  47 , typically made of metal. The cable used on a bicycle brake is one example of a suitable cable. One end of the inner wire  47  is attached to the first flange of the bracket  37  at about the midpoint along the width of the reservoir chamber  1 . Squeezing the grip lever  27  with sufficient force to overcome the biasing force of the springs  43  pulls up the inner wire  47  which slides within the outer sheath  45 . Pulling on the inner wire  47  in turn pulls up the first flange of the bracket  37 . Pulling up on the first flange causes the panel hinge  39  to pivot thereby pivoting the bracket  37 . When the bracket  37  pivots in this manner, the second flange is pulled away from the opening  41  and the gate  29  is opened. Releasing the grip lever  27  permits the springs  43  to pull the second flange back over the opening  41  thereby closing the gate  29 . 
   As best seen in  FIGS. 6 and 8 , in order to prevent accidental opening of the gate  29  caused by pulling on the cable  26  when the handle  15  is pivoted from side-to-side, the outer sheath  45  is fixedly secured at the pivot point  49  of the handle  15  while the inner wire  47  is not fixedly secured at the pivot point  49 . Pivoting of the handle  15  will thereby cause the outer sheath  45  to flex without pulling on the inner wire  47 . 
   As best seen in  FIGS. 6 and 7 , the transparent door  9  on the front face of the reservoir chamber  1  can open and close by pivoting on the door hinge  11 . In order to load a bag  51  of adhesive into the reservoir chamber  1 , the transparent door  9  is opened, the bag  51  is placed in the reservoir chamber  1  and an edge  53  of the bag along the entire width of the gate  29  is pushed through the open gate. To facilitate this operation, the lock  31  on the grip lever  27  may be engaged to keep the gate  29  open while the bag  51  is being loaded. Once the edge  53  of the bag  51  is pushed through the open gate along the entire width, the gate may be closed to pinch the bag thereby leaving a portion of the bag to protrude from the gate. The edge  53  of the bag may then be slit or cut away entirely. When the gate  29  is next opened, adhesive may then flow out of the slit or cut bag under the force of gravity to be deposited on the surface (e.g. the floor) where it can be spread by the action of the spreader pad  7 . Allowing the gate  29  to close pinches the bag closed thereby stopping the flow of adhesive. 
   Referring to  FIGS. 9A ,  9 B,  10 A,  10 B and  10 C, three embodiments of a spreader pad of the present invention are illustrated. In all of these embodiments, the pads comprise a foam material suited for spreading an adhesive. A stiffer, denser foam is more suitable for spreading a thicker material such as tile grout while a less stiffness dense foam is suited for spreading a thinner material such as carpet glue. The heights of the pads are greater than the height of the channel in the pad retaining means so that at least some of the pad extends below the channel. Once a pad is worn down, it may be simply removed and replaced. In operation, adhesive is dispensed on the surface (e.g. floor) within the area bounded by arms and cross-member and the pad is drawn over the adhesive to spread it. 
   Referring to  FIG. 9A , a pad  70  is U-shaped having a two pad arms  71 , 72  and a pad cross-member  73 . The two pad arms  71 , 72  extend at right angles in the same direction from respective ends of the pad cross-member  73 . Slots  74  are cut into the pad on the pad arms  71 , 72  to accommodate the bolts denoted by reference numeral  5  in  FIGS. 1–8 . The pad  70  is sized to fit tightly into the tight tolerance channel of the pad retaining means so that under normal use conditions, the pad may be retained in the pad retaining means by frictional engagement while still being insertable and removable. 
   Referring to  FIG. 9B  a pad  80  is U-shaped having a two pad arms  81 , 82  and a pad cross-member  83 . The two pad arms  81 , 82  extend at right angles in the same direction from respective ends of the pad cross-member  83 . In this embodiment, the entire pad  80  is thicker than can be forced into the channel of the pad retaining means but comprises two grooves  85  separating an inner part  86  from an outer part  87  of the pad  80 . The inner part  86  is sufficiently thick to fit within and frictionally engage the channel of the pad retaining means and the outer part  87  covers outside surfaces of the pad retaining means. Walls of the channel fit within the groove  85 . Slots  84  are cut into the pad on the pad arms  81 , 82  to accommodate the bolts denoted by reference numeral  5  in  FIGS. 1–8 . In operation, the pad  80  works similarly to the pad of  FIG. 9A  except that outside surfaces of the pad retaining means are protected from adhesive. 
   Referring to  FIGS. 10A ,  10 B and  10 C, a pad  90  is U-shaped having two pad arms  91 , 92  and a pad cross-member  93 . The two pad arms  91 , 92  extend at right angles in the same direction from respective ends of the pad cross-member  93 . Slots  94  are cut into the pad on the pad arms  91 , 92  to accommodate the bolts denoted by reference numeral  5  in  FIGS. 1–8 . The pad  90  is sized to fit tightly into the tight tolerance channel of the pad retaining means so that under normal use conditions, the pad may be retained in the pad retaining means by frictional engagement while still being insertable and removable. A serrated spreader blade  96  having a plurality of serrations  97  (only one labeled) is glued to an inside face of the cross-member  93  at a bottom edge thereof. As best seen in  FIG. 10C , the blade  96  is also engaged within grooves  99  cut into the arms  91 , 92 . The blade further comprises a plurality of vertical slits  98  (only one labeled) to impart greater flexibility to the blade. As best seen in  FIG. 10B , the cross-member  93  has a beveled bottom  95  such that the serrated spreader blade  96  extends below the inside bottom edge of the cross-member. The beveled bottom  95  results in the outside bottom edge of the cross-member being higher off the surface than the inside bottom edge of the cross-member, i.e. the outside face of the cross-member is narrower in height than the inside face of the cross-member. 
   Other advantages which are inherent to the structure are obvious to one skilled in the art. The embodiments are described herein illustratively and are not meant to limit the scope of the invention as claimed. Variations of the foregoing embodiments will be evident to a person of ordinary skill and are intended by the inventor to be encompassed by the following claims.