Patent Publication Number: US-11034053-B2

Title: Concrete product machine apron plate gap adjustment

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims the benefit of the filing date of United States Provisional Patent Application Ser. No. 62/856,406, filed Jun. 3, 2019, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Field 
     This application relates generally to adjustable feed trays for molding machines. 
     Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98 U.S. Pat. No. 7,896,517 
     Mold assemblies are interchangeably installed in concrete product machines to shape various concrete products. They have varying shapes and sizes, and top plates of these mold assemblies may have differing lateral depths. Apron plates of these concrete products machines need to maintain a certain lateral gap distance from the top plates of the mold assemblies, and this gap distance must be reset every time a different mold assembly is loaded into the concrete products machines, to accommodate dimensional differences in the mold assemblies and/or mold top plates. 
     Current techniques to achieve and maintain this apron plate gap distance require an operator to move the apron plate away from an installed mold assembly&#39;s top plate by pressing a button or throwing switch on a control panel, which actuates hydraulic cylinders attached to the apron plate. The operator measures the resulting apron plate gap with a tape measure as the apron plate is moved, until the gap reaches the desired size. The operator then manually locks the apron plate into position. This manual adjustment and measuring process is time consuming and inefficient—especially when it needs to be performed frequently. 
     SUMMARY 
     A concrete product machine apron gap adjustment apparatus is provided, which comprises an apron plate supported on a machine frame for reciprocal movement between a retracted position allowing room for installation of an interchangeable mold assembly, and an engaged position against an installed mold assembly. A primary apron plate positioning cylinder is connected between the apron plate and the machine frame and is configured to move the apron plate between the retracted and engaged positions. A gapper mechanism is in fluid communication with the primary apron plate positioning cylinder and is configured to set a desired gap between the machine apron plate and the mold assembly by injecting an index amount of hydraulic fluid into fluid communication with the primary apron plate positioning cylinder which, in response, causes the machine apron plate to retreat a desired gap distance away from its engaged position against the mold assembly. 
     In addition, a method is provided for configuring a concrete product machine to automatically set a desired gap between an apron plate of the machine and a mold assembly installed in the machine. The method includes installing an apron plate gapping cylinder in the machine, in fluid communication with a primary apron plate positioning cylinder of the machine, and in electrical communication with a controller of the machine. The method also includes programming a controller to execute the step of commanding the apron plate to advance into engagement with a mold assembly installed in the machine, by actuating the primary apron plate positioning cylinder; as well as the step of commanding the apron plate to retreat from engagement with the mold assembly by the desired gap distance by actuating the gapping cylinder to expel the index amount of hydraulic fluid from the apron plate gapping cylinder into the primary apron plate positioning cylinder. 
    
    
     
       DRAWING DESCRIPTIONS 
         FIG. 1  is an orthogonal view of a concrete product machine comprising an apron plate and an apron gap adjustment apparatus, and having a mold assembly interchangeably installed; 
         FIG. 2  is a magnified view of a portion of the concrete product machine of  FIG. 1  including the apron plate and mold assembly; 
         FIG. 3  is an orthogonal view of the apron plate and mold assembly of  FIG. 2 ; 
         FIG. 4  is a schematic diagram of a hydraulic circuit of the concrete product machine and apron gap adjustment apparatus of  FIG. 1 ; 
         FIG. 5  is a flowchart showing a method for setting a desired apron plate gap between the mold assembly and apron plate of  FIG. 3 ; 
         FIG. 6  is an orthogonal view of the apron plate and mold assembly of  FIG. 3 , with the apron plate in a retracted position providing sufficient space between the apron plate and mold assembly to remove and replace the mold assembly; 
         FIG. 7  is an orthogonal view of the apron plate and mold assembly of  FIG. 3 , with the apron plate in an engaged position against the mold assembly top plate; 
         FIG. 8  is an orthogonal view of the apron plate and mold assembly of  FIG. 3 , with the apron plate spaced the desired gap distance from the mold assembly; and 
         FIG. 9  is a flowchart showing a method of configuring a concrete product machine to automatically set a desired gap between an apron plate of the machine and a mold assembly installed in the machine. 
     
    
    
     DETAILED DESCRIPTION 
     A concrete product machine apron gap adjustment apparatus is shown at  10  in  FIGS. 1, 3, and 6-8 . The apparatus may include an apron plate  12  supported on a frame of a concrete products machine  14  for reciprocal movement between a retracted position (shown in  FIG. 6 ) that allows room for removal and installation of an interchangeable mold assembly  16 , and an engaged position (shown in  FIG. 7 ) against an installed mold assembly  16 . Specifically, the apron plate  12  may engage against a top plate  18  of the installed mold assembly  16 . 
     The apparatus  10  may also include at least one, and preferably two, primary apron plate positioning cylinders  20  that may be connected between the apron plate  12  and the machine frame  14 . The apparatus  10  may accordingly include at least one, but preferably two, primary apron plate positioning cylinder hydraulic circuits  22 , each of which may be connected to and in fluid communication with one of the primary apron plate positioning cylinders  20 . The primary apron plate positioning cylinders  20  may be configured and actuable to move the apron plate  12  between the retracted and engaged positions. 
     The apparatus  10  may also include a gapper mechanism  24 , as shown in  FIG. 4 , that may include at least one, but preferably two, apron plate gapping cylinders  25  that may be in fluid communication with the primary apron plate positioning cylinders  20  through the hydraulic circuits  22 . The gapper mechanism  24  may also include first and second hydraulic directional valves  27 ,  29 . The first directional valve  27  may be in fluid communication with the gapping cylinders  25 , and the first directional valve  27  may be actuable to allow hydraulic fluid to escape from the gapping cylinders  25 . The second hydraulic directional valve  29  may be in fluid communication with the two apron plate gapping cylinders  25  via the hydraulic circuit  22 . second hydraulic directional valve  29  may be actuable to allow hydraulic fluid to flow into the two apron plate gapping cylinders  25 , causing the cylinders to expel fluid into the gapping cylinders  25 . 
     The gapper mechanism  24  may be configured to set a desired gap between the machine apron plate  12  and the mold assembly top plate  18  by injecting an index amount of hydraulic fluid into fluid communication with the primary apron plate positioning cylinders  20 , causing the machine apron plate  12  to retreat a desired gap distance away from its engaged position against the mold assembly  16 . By injecting an index amount of fluid when the apron plate  12  is in the engaged position, the gapper mechanism  24  ensures that a consistent gap is produced between a mold assembly  16  and the apron plate  12 , even if mold assemblies  16  and/or mold assembly top plates  18  of varying dimensions are installed in the apparatus  10 . For example, the gapping mechanism  24  may be configured to produce a desired gap of 1/32- 1/16 inches, however other gap sizes may be desired according to the needs of the concrete products machine  14 . 
     The apparatus  10  may comprise a controller  26  connected in electrical communication with the gapper mechanism  24  and the apron plate positioning cylinders  20 . The controller  26  may be further configured to receive commands from an operator via a human/machine interface (HMI)  28 . The controller  26  may be programmed to automatically set a proper gap between the apron plate  12  and the mold assembly  16  in response to a gapping command. According to this programming, when the controller  26  receives the gapping command, the controller  26  should actuate the primary apron plate positioning cylinders  20  to advance the apron plate  12  into engagement with the mold assembly  16 , and command the gapping cylinders  25  to expel the index amount of hydraulic fluid from the apron plate gapping cylinders  25  into the primary apron plate positioning cylinders  20 , thereby causing the apron plate  12  to retreat the desired gap distance from the mold assembly  16 . 
     In practice, and as shown in  FIG. 5 , the desired gap may be set between the apron plate  12  and a mold assembly  16  in the concrete product machine  14  via the following procedure: 
     First, as shown in  FIG. 6 , the apron plate  12  must be retracted as necessary to provide sufficient space to install an interchangeable mold assembly  16 . This may be accomplished by an operator input at the HMI  28 , which actuates the apron plate positioning cylinders  20  to retract the apron plate  12 . An interchangeable mold assembly  16  may then be installed in the concrete product machine  14 . 
     An operator may issue a gapping command via the HMI  28  to begin the gapping process. The point at which this command is issued may vary, and the gapping command may be included with, or triggered by, other commands. For example, the HMI  28  may be configured and programmed so that the gapping command may be issued by the operator after the mold  16  installation is complete, alternatively, the operator may issue the gapping command as part of an automated series of commands issued by the controller  26  in response to pressing an HMI button that begins the whole mold  16  installation and gapping process. As a further alternative, the gapping command may be automatically issued in response to some other operator input such as the installation of a new mold assembly  16 . 
     Once the mold assembly  16  is installed, and the gapping command has been issued, the controller  26  may respond to the gapping command by causing the apron plate  12  to advance into engagement with the mold assembly  16  as shown in  FIG. 7 . The controller  26  may then cause the apron plate  12  to retreat from engagement with the mold assembly  16 , as shown in  FIG. 8 , and create a desired gap between the machine apron plate  12  and the mold assembly  16  by causing an index amount of hydraulic fluid to be expelled from the apron plate gapping cylinders  25  into the rod sides  23  of hydraulic circuits  22  that the primary apron plate positioning cylinders  20  are connected into. 
     Actuation of the two apron plate gapping cylinders  25  may include causing the first hydraulic directional valve  27  to open and then, ½ second later, causing the second hydraulic directional valve  29  to open, and causing both hydraulic directional valves  27 ,  29  to remain open for an additional second. This should cause the apron plate gapping cylinders  25  to extend and expel the index amount of hydraulic fluid, which should cause the apron plate  12  to retreat a desired distance of 1/32- 1/16 inch away from the mold assembly top plate  18 . 
     In practice, and as shown in  FIG. 9 , a concrete products machine  14  may be configured to automatically set a desired gap between an apron plate  12  of the machine and a mold assembly  16  installed in the machine  14  according to the following steps: First, the gapper mechanism  24 , including the gapper cylinders  25 , may be installed in fluid communication, via the hydraulic circuits  22 , with the primary apron plate positioning cylinders  20  of the machine, and in electrical communication with a controller  26  of the machine  14 . Next, the controller  26  may be programmed to execute the following steps when the controller  26  receives a gapping command: (1) command the apron plate  12  to advance into engagement with a mold assembly  16  installed in the machine  14 , by actuating the primary apron plate positioning cylinders  20 ; and (2) command the apron plate  12  to retreat from engagement with the mold assembly  16  by the desired gap distance by actuating the gapping cylinders  25  to expel the index amount of hydraulic fluid from the apron plate gapping cylinders  25  into the primary apron plate positioning cylinders  20 . 
     To ensure that the correct gap distance is consistently produced, a target parameter value may be determined that corresponds to the index amount of hydraulic fluid required to be expelled from the apron plate gapping cylinders  25  into a primary apron plate positioning cylinder to produce the desired gap. This target parameter value determination may be performed via various means including trial and error, measurement, experimentation, and/or via calculation. The parameter may, for example, be time; and the target parameter value may be the length of time that a hydraulic valve must remain open to release the index amount of hydraulic fluid. Once the target parameter value is determined, it may be used in the step of programming the controller  26  as a means of controlling the amount of hydraulic fluid expelled by the gapping cylinders  25 . For example, the controller  26  may be programmed to expel hydraulic fluid until the controller  26  perceives that the target parameter value has been met. 
     A concrete product machine apron gap adjustment apparatus constructed as disclosed above, and concrete product machine configuration and apron gap adjustment methods executed as disclosed above, will allow the automatic and consistent setting of a desired gap between a concrete product machine apron plate and any number of differently-configured mold assemblies interchangeably installed in the concrete product machine. 
     This description, rather than describing limitations of an invention, only illustrates (an) embodiment(s) of the invention recited in the claims. The language of this description is therefore exclusively descriptive and is non-limiting. Obviously, it&#39;s possible to modify this invention from what the description teaches. Within the scope of the claims, one may practice the invention other than as disclosed above.