Abstract:
A method of making a masonry block employing a mold assembly having a plurality liner plates each having a major surface that together form a mold cavity having an open top and an open bottom, wherein at least one liner plate is moveable between a retracted position and a desired extended position. The method includes providing a negative of a desired texture on the major surface of the moveable liner plate, moving the moveable liner plate to a retracted position, closing the bottom of the mold cavity by positioning a pallet below the mold assembly, filling the mold cavity with dry cast concrete via the open top, and vibrating the mold assembly and dry cast concrete therein. The method further includes moving the moveable liner plate toward a desired extended position after the mold cavity has been filled with dry cast concrete, before the open top of the mold cavity is closed, and while the mold assembly is vibrating, and closing the open top of the mold cavity with a head shoe assembly subsequent to commencement of the vibrating and the moving of the moveable liner plate toward the desired extended position.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This Non-Provisional Patent Application is a Continuation Application of U.S. Utility application Ser. No. 12/407,568, filed on Mar. 19, 2009, entitled: SYSTEM AND METHOD OF MAKING MASONRY BLOCKS which in-turn claims benefit of U.S. Provisional Application No. 61/038,144, filed Mar. 20, 2008, both of which are incorporated herein. 
     
    
     BACKGROUND 
       [0002]    Concrete blocks, also referred to as concrete masonry units (CMU&#39;s), are typically manufactured by forming them into various shapes as part of an automated process employing a concrete block machine. Such machines typically employ a mold frame assembled so as to form a mold box, within which a mold cavity having a negative of a desired block shape is formed. To form a block, a pallet is moved by a conveyor system onto a pallet table, which is then moved upward until the pallet contacts and forms a bottom of the mold cavity. 
         [0003]    The mold cavity is then filled with concrete and a head shoe assembly is positioned to form a top of the mold cavity. The head shoe assembly then compresses the concrete (typically via hydraulic or mechanical means) to a desired psi rating (pounds-per-square-inch) while simultaneously vibrating the mold cavity along with the vibrating table. As a result of the compression and vibration, the concrete reaches a level of “hardness” which enables the resulting finished block to be immediately removed from the mold cavity. To remove the finished block, the mold frame and mold cavity remain stationary while the shoe assembly, pallet, and pallet table move downward and force the finished block from the mold cavity. The conveyor system then moves the pallet bearing the finished block away and a clean pallet takes its place. This process is repeated for each block. 
         [0004]    For many types of CMUs (e.g. pavers, patio blocks, light-weight blocks, cinder blocks, etc.), retaining wall blocks and architectural units in particular, it is desirable for at least one surface of the block to have a desired texture, such as a stone-like texture, for instance. When arranged to form a structure with the textured surface visible, the structure will have the appearance of being constructed from natural stone. 
         [0005]    One technique for creating a desired texture on a block surface is to provide a negative of a desired texture or pattern on a moveable side wall of the mold cavity. During the manufacturing process, the side wall is moved to an extended position to form the mold cavity. As described above, the mold cavity is then filled with concrete and compressed/vibrated. The side wall is then moved to a retracted position and the finished block, as described above, is forced from the mold cavity and onto the pallet by the head shoe assembly. The finished block, including a surface having the desired texture, is then transported on the pallet by the conveyor for curing. 
         [0006]    While such a technique is effective at forming a textured surface, air pockets trapped between the textured surface of the moveable side wall and concrete fill are forced out during the compression/vibration process, causing the concrete to settle proximate to the textured surface and resulting in the finished block having a height along the textured surface (e.g. front face of block) which is shorter than that along an opposite surface (e.g. rear face of block). Consequently, unless compensated for in some fashion, a structure (e.g. a retaining wall) will tend to have an undesirable lean in a direction toward the textured surface. 
       SUMMARY 
       [0007]    According to one example, a method of making a masonry block is provided which employs a mold assembly having a plurality liner plates each having a major surface that together form a mold cavity having an open top and an open bottom, wherein at least one liner plate is moveable between a retracted position and a desired extended position within the mold cavity. The method includes providing a negative of a desired texture on the major surface of the moveable liner plate to impart the desired texture to a surface of the masonry block corresponding to the moveable liner plate, moving the moveable liner plate to a retracted position, closing the bottom of the mold cavity by positioning a pallet below the mold assembly, filling the mold cavity with dry cast concrete via the open top, and vibrating the mold assembly and dry cast concrete therein. The method further includes moving the moveable liner plate toward a desired extended position after the mold cavity has been filled with dry cast concrete, before the open top of the mold cavity is closed, and while the mold assembly is vibrating, and closing the open top of the mold cavity with a head shoe assembly subsequent to commencement of the vibrating and the moving of the moveable liner plate toward the desired extended position. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a perspective view illustrating generally one embodiment of a mold assembly according to embodiments of the present invention. 
           [0009]      FIG. 2  is a top view illustrating generally one embodiment of a drive assembly according to embodiments of the present invention. 
           [0010]      FIG. 3  is a sectional view of the drive assembly of  FIG. 2 . 
           [0011]      FIG. 4A  illustrates a masonry block formation process according to embodiments of the present invention. 
           [0012]      FIG. 4B  illustrates a masonry block formation process according to embodiments of the present invention. 
           [0013]      FIG. 4C  illustrates a masonry block formation process according to embodiments of the present invention. 
           [0014]      FIG. 4D  illustrates a masonry block formation process according to embodiments of the present invention. 
           [0015]      FIG. 5   a  illustrates a masonry block formed by a masonry block formation process according to embodiments of the present invention. 
           [0016]      FIG. 5   b  illustrates a masonry block formed by a masonry block formation process according to embodiments of the present invention. 
           [0017]      FIG. 6  is an example structure formed by the masonry block of  FIG. 5 . 
           [0018]      FIG. 7A  is masonry block formed by conventional methods. 
           [0019]      FIG. 7B  is an example structure formed by the masonry block of  FIG. 7A . 
           [0020]      FIG. 8  is a flow diagram illustrating one embodiment of a masonry block formation process according to embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. 
         [0022]      FIG. 1  is a perspective view illustrating generally one embodiment of a mold assembly  30  having at least one moveable liner plate and which is suitable for forming a masonry block having at least one textured surface, or face, according to embodiments of the present invention. Mold assembly  30  is configured and adapted for use in an automated concrete block machine, such as those machines manufactured by Besser Company (Alpena, Mich.) and Columbia Machine, Inc. (Vancouver, Wash.), for example. Mold assembly  30  includes a mold frame having side-members  34   a  and  34   b  and cross-member  36   a  and  36   b  that are coupled to one another to form a mold box  38 . A plurality of liner plates  40 , illustrated as liner plates  40   a,    40   b,    40   c,  and  40   d  are positioned within mold box  38  to form a mold cavity  42 , wherein the plurality of liner plates are positioned to form a desired shape for a masonry block to be formed therein. 
         [0023]    In one embodiment, as illustrated, liner plate  40   a  is moveable between a retracted and a desired extended position within mold box  38 , while liner plates  40   b,    40   c,  and  40   d  are stationary. In other embodiments, up to all liner plates of the plurality of liner plates  40  are moveable between a corresponding extended and refracted position within mold box  38  to form mold cavity  42 . In one embodiment, as illustrated, moveable liner plate  42   a  includes a liner face  44  having a negative of a desired texture, pattern, or other design to be formed on a face of a masonry block to be molded within mold cavity  42  by mold assembly  30 . 
         [0024]    Mold assembly  30  further includes a drive assembly  46  which is selectively coupled to and configured to drive moveable liner plate  40   a  and thus, moveable liner face  44 , between the retracted and desired extended positions within mold cavity  42 . In one embodiment, as will be described in greater detail below by  FIGS. 2 and 3 , drive assembly  46  includes a position sensor configured to provide an indication of a position of moveable liner plate  40   a  within mold cavity  42 , wherein drive assembly  46  moves moveable liner plate  40   a  to a desired extended position within mold cavity  42  based on the position indication from the position sensor. 
         [0025]    Mold assembly  30  is configured to selectively couple to a concrete block machine. For ease of illustration, the concrete block machine is not shown in  FIG. 1 . In one embodiment, mold assembly  30  is mounted to the concrete block machine by bolting side members  34   a  and  34   b  to the concrete block machine. In one embodiment, mold assembly  30  further includes a head shoe assembly  50  having dimensions similar to those of mold cavity  46  and which is also selectively coupled to the concrete block machine. During formation of a masonry block, head shoe assembly  50  and a pallet  52  respectively form a top and a bottom of mold cavity  42 . 
         [0026]      FIG. 2  is a top view of portions of mold assembly  30  of  FIG. 1 , and illustrates generally a block and schematic diagram of one embodiment of drive assembly  46  according to the present invention. Drive assembly  46  is substantially enclosed within a housing  60  which is coupled to side member  34   a  by support shafts  62  and  64 . In one embodiment, support shafts  62  and  64  extend through corresponding openings in housing  60  and thread into corresponding threaded openings in side member  34   a.  In one embodiment, support shafts  62  and  64  are cylindrical in shape. In one embodiment, support shafts  62  and  64  comprise stainless steel or other non-magnetic materials. 
         [0027]    Drive assembly  46  further includes a master bar  66  having openings  68  and  70  through which support shafts  62  and  64  extend. In one embodiment, master bar  66  includes bushings  72  and  74  respectively mounted within openings  68  and  70 . In one embodiment, bushings  72  and  74  comprise brass or other non-magnetic materials. Guide posts  76  and  78  are coupled between master bar  66  and moveable liner plate  40   a  and extend through corresponding openings  80  and  82  in side member  34   a.  A first drive element  84  having a plurality of angled channels  86  (illustrated by dashed lines) is coupled between master bar  66  and moveable liner plate  40   a  and extends through a corresponding opening  88  in side member  34   a.    
         [0028]    Drive assembly  46  further includes an actuator assembly  90 . In one embodiment, as illustrated, actuator assembly  90  comprises a double-rod end hydraulic piston assembly including a dual-acting cylinder  92  and a hollow piston rod assembly  94  having a first hollow rod-end  96  and a second hollow rod-end  98 . First and second hollow rod-ends  96  and  98  are stationary and extend through removable housing  60 . Hydraulic fittings  100  and  102  respectively connect first and second hollow rod-ends  96  and  98  to a controller  104  via hydraulic fluid lines  106  and  108 . 
         [0029]    A second drive element  110  having a plurality of angled channels  112  configured to slideably interlock with the plurality of angled channels  86  of first drive element  84  is coupled to dual-acting cylinder  92 . In one embodiment, the plurality of angled channels  112  are formed as part of a body of dual-acting cylinder  92  such that second drive element  110  is contiguous with the body of dual-acting cylinder  92 . In one embodiment, as illustrated by  FIG. 3 , which is a cross-sectional view illustrating portions of drive assembly  46  of  FIG. 2 , second drive element  110  is separate from and coupled to dual-acting cylinder  92 . In one embodiment, as illustrated by  FIG. 3 , dual-acting cylinder  92  is positioned internal to second drive element  110 . 
         [0030]    A drive assembly similar to drive assembly  46 , including an actuator assembly employing gear elements and interlocking angled channels, similar to actuator assembly  90  and first and second drive elements  84  and  110 , is described by U.S. patent application Ser. No. 10/629,460 assigned to the same assignee as the present invention (now U.S. Pat. No. 7,156,645), and which is incorporated herein by reference. 
         [0031]    In one embodiment, drive assembly  46  further includes a magnetic sensor assembly  120  configured to provide a position signal  122  indicative of a position of moveable liner plate  40   a  to controller  104 . In one embodiment, magnetic sensor assembly comprises a linear position sensor. Magnetic sensor assembly  120  includes a stationary magnetic sensor probe  124  which is mounted within a bored shaft internal to support shaft  62 , and a permanent magnet  126  which is mounted to bushing  72  and which, as will be described below, is free to slide along support shaft  62  with master bar  66  when driven by double-rod end hydraulic piston assembly  90 . The position of permanent magnet  126  relative to magnetic sensor probe  124  and, thus, a position of moveable liner plate  40   a  relative to mold cavity  42 , is indicated by position signal  122 . In one embodiment, magnetic sensor assembly  120  comprises a Model No. TMI0400002111102 linear position sensor as manufactured by Novotechnik, Southborough, Mass., USA. 
         [0032]    In operation, with reference to  FIGS. 1-3  above, drive assembly  46  is configured to move moveable liner plate  40   a  and corresponding liner face  44  between a retracted position  130  and a desired extended position  132 , indicated by dashed lines on  FIGS. 2 and 3 . To move liner plate  40   a  toward desired extended position  132 , controller  104  transmits hydraulic fluid into dual-acting cylinder  92  via hydraulic line  106  and first hollow rod-end  96  causing dual-acting cylinder  92  and angled channels  112  of second drive element  110  to move along hollow piston rod  94  toward second hollow rod-end  98 , and causing hydraulic fluid to expelled from second hollow rod-end  98  via hydraulic line  108 . As dual-acting cylinder  92  moves toward second hollow rod-end  98 , the plurality of angled channels  112  of second drive element  110  interact with the plurality of angled channels  86  and drive first drive element  84  and moveable liner plate  40   a  toward desired extended position  132 . 
         [0033]    Because first drive element  84  is coupled to master bar  66 , driving first drive element  84  toward desired extended position  132  also causes master bar  66  and guide posts  76  and  78  to move toward desired extended position  132 . As master bar  66  moves toward mold cavity  42 , permanent magnet  126  slides along support shaft  62  and, thus, along stationary magnetic sensor probe  124 . As permanent magnet  126  moves along a length of stationary magnetic probe  124 , magnetic sensor assembly  120  provides position signal  122  indicative of the position of permanent magnet along support shaft  62  and, thus, indicative of the position of moveable liner plate  40   a  relative to mold cavity  42 . When position signal  122  indicates that moveable liner plate  40   a  has reached desired extended position  132 , controller  104  stops transmitting hydraulic fluid to dual-acting cylinder  92  and maintains moveable liner plate  40   a  at desired extended position  132 . It is noted that extended position  132  may vary for various type of masonry blocks formed by mold assembly  30 . 
         [0034]    Conversely, to move liner plate  40   a  away from mold cavity  42  toward retracted position  130 , controller  104  transmits hydraulic fluid into dual-acting cylinder  92  via hydraulic line  108  and second hollow rod-end  9 , causing dual-acting cylinder  92  and angled channels  112  of second drive element  110  to move along hollow piston rod  94  toward first hollow rod-end  96 , and causing hydraulic fluid to be expelled from first hollow rod-end  96  via hydraulic line  106 . As dual-acting cylinder  92  moves toward first hollow-rod end  96 , the plurality of angled channels  112  of second drive element  110  interact with the plurality of angled channels  86  of drive element  84  and drive moveable liner plate  40   a  away from extended position  132  toward retracted position  130 . In a fashion similar to that described above, when position signal  122  indicates that moveable liner plate  40   a  has reached retracted position  130 , controller  104  stops transmitting hydraulic fluid to dual-acting cylinder  92  and maintains moveable liner plate  40   a  at retracted position  130 . 
         [0035]      FIGS. 4A through 4D  are simplified illustrations of mold assembly  30  of  FIGS. 1-3  and illustrate the formation of a masonry block employing a block formation process according to embodiments of the present invention.  FIG. 4A  is a top view of mold assembly  30  showing moveable liner plate  40   a  in retracted position  130 . In one embodiment, while moveable liner plate  40   a  is in retracted position  130 , mold cavity  42  is filled with concrete. In one embodiment, moveable liner plate  40   a  is in a partially extended position when mold cavity  42  is filled with concrete. 
         [0036]    In one embodiment, after mold cavity  42  is filled with concrete, head shoe assembly  50  is moved downward to mold cavity  42 . The concrete block machine in which mold assembly  30  is installed (not shown) then begins to vibrate mold assembly  30  and head shoe assembly  50  begins to compress the concrete within mold cavity  42  as drive assembly  46  drives moveable liner plate  40   a  toward extended position  132 . When position signal  122  indicates that moveable liner plate  40   a  has reached desired extend position  132 , drive assembly  46  stops moving liner plate  40   a  and maintains it at extended position  132 , and the vibration and compression continues as necessary.  FIG. 4B  illustrates moveable liner plate  40   a  and textured liner face  44  after reaching extended position  132 . 
         [0037]      FIGS. 4C and 4D  are side views of mold assembly  30  of  FIGS. 4A and 4B  and respectively illustrate head shoe assembly  50  in a raised position and in a lowered position relative to mold cavity  42 . In one embodiment, head shoe assembly  50  includes a notch  136  which, as will be described below, forms a set-back flange in a masonry block formed by mold assembly  30 . In one embodiment, as described above, head shoe assembly  50  is lowered onto mold cavity  42  prior to movement of liner plate  40   a  by drive assembly  46  and vibration of mold assembly  30 . In another embodiment, head shoe assembly is lowered onto mold cavity  42  and begins to compress the concrete therein after drive assembly  46  begins to drive moveable liner plate  40   a  toward extended position  132  and after the concrete block machine begins to vibrate mold assembly  30 . 
         [0038]    By moving moveable liner plate  40   a  to extended position  42  after mold cavity  42  has been filled, and by compressing and vibrating the concrete within mold cavity  42  as moveable liner plate  40   a  is being moved toward extended position  132 , air pockets trapped between the concrete within mold cavity  42  and textured liner face  44  are substantially removed during the block formation process. 
         [0039]      FIGS. 5A and 5B  illustrate an example of a masonry block  140  formed by mold assembly  30  of  FIGS. 1-3  and the process described above by  FIGS. 4A through 4D . Masonry block  140  is commonly referred to as a retaining wall block. Retaining wall block  140  includes a front face  142  having a three-dimensional pattern formed by textured liner face  44  of moveable liner plate  40   a,  a rear face  144  formed by stationary liner plate  40   c,  and opposing side faces  146  and  148  respectively formed by stationary liner plates  40   b  and  40   d.  A bottom face  150  is formed by head shoe assembly  50  and an opposing top face  152  is formed by pallet  52 . In one embodiment, as illustrated, bottom face  150  includes a set-back flange  154  extending from bottom face  150  along an edge formed with rear face  144 , wherein set-back flange  154  is formed through cooperation between notch  136  of head shoe assembly  50  and stationary liner plate  40   c.  In one embodiment, as illustrated, opposing side face  146  and  148  are angled inwardly from front face  142  toward rear face  144  at an angle (θ)  156 . Set-back flange  154  is formed through cooperation between stationary liner plate  40   c  and notch 
         [0040]    With reference to  FIG. 5B , which is a side view of retaining wall block  140 , by compressing and vibrating the concrete within mold cavity  42  as moveable liner plate  40   a  is being moved toward extended position  132 , substantially all air trapped between the concrete within mold cavity  42  and textured liner face  44  is removed during the block formation process such that a height h 1   158  of front face  142  is substantially the same as a height h 2   160  proximate to rear face  144  and set-back flange  154 . 
         [0041]    Retaining wall blocks, such as retaining wall block  140 , are generally stacked in courses to form a structure, such as a retaining wall or planting bed, for example. Set-back flange  154  is adapted to abut against a rear face of a similar block in a course of blocks below retaining wall block  140  so as to position front face  142  at a desire set-back distance from the front face of the blocks in the course below.  FIG. 6  is a cross-sectional view of an example soil retention wall  170  constructed using masonry blocks  140  as illustrated by  FIGS. 5A and 5B . Because height h 1   158  is substantially equal to height h 2   160 , each successive course of blocks of soil retention wall  170  is substantially horizontal. 
         [0042]      FIG. 7A  is a side view illustrating a masonry block  180 , which is similar to masonry block  140 , but 5 formed by a concrete block machine employing a conventional formation method of filling, compacting, and vibrating the concrete fill after a moveable liner plate having a desired texture is positioned at an extended position. As illustrated, because air trapped between the textured surface of the moveable liner plate and the concrete fill is removed after the moveable liner plate is in the extended position, the concrete fill is compressed and settles such that a height h 3   182  of a textured front face  184  is less than a height h 4   186  proximate to a rear face  188  and a set-back flange  189 . As such, when stacked to form a soil retention wall  190 , as illustrated by  FIG. 7B , each course of blocks is tilted downward from horizontal such that soil retention wall  190  leans further downward from horizontal with each successive course of blocks causing soil retention wall  190  to have a forward lean. Such a forward lean is undesirable and may cause soil retention wall  190 , or other structure formed using masonry blocks  180 , to become unstable. 
         [0043]      FIG. 8  is a flow diagram illustrating one embodiment of a process  200  for forming masonry blocks according to the present invention. Process  200  begins at  202 , where mold assembly  30  is mounted to a concrete block machine, such as by bolting side members  34   a  and  34   b  to the concrete block machine. In one embodiment, mold assembly  30  further includes head shoe assembly  50 , which is also bolted to the concrete block machine. 
         [0044]    At  204 , one or more liner plates, such as moveable liner plate  40   a,  are positioned at a beginning or starting position. In one embodiment, the starting position comprises the corresponding retracted position of each moveable liner plate. In one embodiment, the starting position comprises a partially extended position. Depending on a particular implementation and a particular type of masonry block to be formed, mold assembly  30  may include one or more moveable liner plates. At  206 , the concrete block machine positions pallet  52  so as to form a bottom for mold cavity  42 . 
         [0045]    At  208 , the concrete block machine fills mold cavity  42  with a desired concrete mixture. At  210 , after mold cavity  42  has been filled with concrete, head shoe assembly  50  is lowered onto mold cavity  42 . At  212 , the concrete block machine begins vibrate the concrete and to compress the concrete with head shoe assembly  50 . Concurrently, controller  104  begins to move moveable liner plate  40   a  toward the desired extended position from the starting position (e.g. retracted position, partially extended position). When magnetic sensor assembly  120  indicates via position signal  122  that moveable liner plate  40   a  has reached the desired extended position, such as desired extended position  132 , controller  104  stops moving moveable liner plate  40   a  and maintains it at the desired extended position. In one embodiment, after reaching the desired extended position, the concrete block continues to vibrate and compress the concrete fill within mold cavity  42  to achieve a desired psi rating. 
         [0046]    At  214 , after the concrete has been compressed and vibrated, the one or more moveable liner plates are moved to a retracted position. At  216 , after the one or more liner plates have been moved to a corresponding retracted position, the concrete block machines removes the formed masonry block from mold cavity  42  by moving head shoe assembly  50  and pallet  52  downward while mold assembly  30  remains stationary. At  218 , head shoe assembly  50  is raised to an original starting position, and the above described process is repeated for the formation of each subsequent block. 
         [0047]    As described above and by previously incorporated U.S. patent application Ser. No. 10/629,460, drive assembly  46  employing first and second gear elements  84  and  110  provides a robust drive assembly that enables moveable liner plate  40   a  to be moved to a desired extended position while the concrete fill within mold cavity  42  is being compacted by head shoe assembly  50  and vibrated by the concrete block machine. Additionally, magnetic sensor assembly  120  provides accurate indication of the position of moveable liner plate  40   a  and is not as susceptible to vibration and other adverse conditions (e.g. dirt, debris) as other types of sensors (e.g. position switches, optical sensors). Other types of drive assemblies, however, may be employed, such as those drive assemblies described by U.S. patent application Ser. No. 11/351,770 filed on Feb. 10, 2006, and assigned to the same assignee as the present invention (now U.S. Pat. No. 7,470,121), and which is incorporated herein by reference. 
         [0048]    Additionally, although described herein primarily with respect to movement of a single liner plate and with respect to formation of a masonry retaining wall block, the teachings of the present invention apply to a mold assembly having multiple moveable liner plates and to the formation of other types of masonry blocks, such as architectural units, pavers, and cinder blocks, for example. 
         [0049]    Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof.