This invention relates to apparatus for assembling and fastening together core elements of core assemblies, and more particularly, to apparatus for fastening together an assembly of the water jacket core and slab core of a V-block for an internal combustion engine.
The manufacture of castings for internal combustion engines poses difficult manufacturing problems. For example, the manufacture of a V-block for an internal combustion engine frequently requires that large and unwieldy cores be placed together in a sub-assembly, which is then assembled with another core or placed in a casting mold. In one such operation, the water jacket core and slab core for casting a V-block engine must be assembled into a “jacket and slab” sub-assembly that is subsequently assembled in its entirety into a crankcase core. Because of their weight and size, the water jacket core and slab core of the “jacket and slab” sub-assembly are frequently separated and broken in handling, or are damaged since the cores are fragile and easily broken. These mishaps require production delays in which the production line is frequently stopped so that the broken or damaged cores can be removed.
In the past, adhesive and/or screws have been used to fasten core elements together to maintain the integrity of the core assembly during its handling and during pouring of the casting. The use of an adhesive requires an adhesive that can be easily spread on the core elements, that will set within the shortest possible time; that will hold the core elements together as one piece and maintain their position during the casting process, and that may be removed from the casting after the casting metal solidifies. This method results in substantial costs and opportunities for unreliable castings because of a potentially unreliable interface between the core elements. The adhesive materials may separate or otherwise become degraded in storage. It is also necessary that workmen apply the adhesive correctly so that the adhesive reliably maintains the core elements together during casting and is not spread onto an exposed casting surface. Furthermore, this method requires time for applying the adhesive, assembling the core elements together and allowing the adhesive to set before the core elements can be used for casting, and it introduces into the mold an unnecessary foreign element in the form of an adhesive that may evolve gas that may become trapped in the solidified casting and cause areas of possible failure. Because of the difficulties of using adhesive to fasten core elements together, screws have been used to fasten the core elements of core assemblies together. The use of screws requires the installation of accurately sized pins in the mold-form for the core to provide accurately sized holes in the core to accept the screws. Such pins in the mold-form became eroded by the abrasive core sand and bent in use, resulting in holes in the core that are too small or that cannot accept screws from an automatic installation station. As a result, screws frequently fail to properly engage the core sand core elements and to provide holding engagement of the core sand element as a result of core sand stripping during their installation.
Neither adhesive nor screws can satisfactorily fasten together assemblies of core elements, such as water jacket core, and slab cores for V-blocks of internal combustion engines.
The invention provides an apparatus by which an assembly of core elements, such as an assembly including a water jacket core and slab core, can be easily and rapidly fastened together, avoiding their separation and breakage in subsequent handling, and eliminating associated production line delays, and includes the use of smooth surface fasteners, such as staples, as the fastener means.
The invention provides an apparatus for automatically fastening together one or more sets of assembled sand cores, each set including, for example, a water jacket core and a slab core for an internal combustion engine block. The apparatus of the invention comprises a support for the one or more sets of assembled sand cores, each of which, for example, includes a water jacket core and a slab core for an internal combustion engine, a plurality of movable carriers for a plurality of staple guns, each of the plurality of movable carriers being drivable between a retracted position and a staple insertion position adjacent the two sets of core assemblies on said support. Each of the movable carriers carries a plurality of staple guns and a supply of staples for each staple gun, an actuator for operating each staple gun and a staple sensor for sensing the insertion of staples from each of the staple guns. The apparatus further includes a core assembly sensor for sensing the presence of the one or more sets of assembled sand cores at their fastening positions on the support, and a control having first control means triggered by said core assembly sensor for actuating the movement of the plurality of movable carriers between their retracted positions and their staple insertion positions, second control means for operating the staple gun actuators when the movable carriers have reached their staple insertion positions, and third control means triggered by signals from the plurality of staple sensors for actuating the movement of the plurality of carrier drivers to their retracted positions. Preferably in the invention, each of the plurality of staple guns is located at the staple insertion position so that each of the plurality of staple guns inserts a single staple into both of assembled cores, each such single staple having one tine inserted into one of the cores and the other tine inserted into the other of the cores with the crown of the staple crossing the interface between the cores thereby retaining the cores of the one or more sets of assembled sand cores together. In the invention, the retracted positions of the plurality of movable carriers are preferably below the level of the support so that a work carrier, such as a pick-and-place robot, can place the one or more sets of assembled sand cores on the support without obstruction.
A preferable apparatus of the invention automatically fastens together two sets of assembled sand cores, each set including a water jacket core and a slab core for internal combustion engine block, and includes a table and a plurality of supports for the two sets of assembled sand cores, each of which extend upwardly from the table. A pair of movable carriers, each of which carry a pair of automatically operable staple guns, are provided, with one movable carrier and one pair of staple guns being located on one side of the table and the second movable carrier and pair of staple guns being located on the opposite side of the table. Each of the movable carriers have a retracted position below the level of the table and a staple insertion position in which each pair of staple guns is located adjacent the two sets of assembled sand cores which rest on the plurality of supports. The movable carriers further include actuators to move the plurality of automatically operable staple guns upwardly and inwardly from their retracted positions to their staple insertion positions. Each of the movable carriers carry, in addition to the pair of staple guns, two supplies of staples, one for each staple gun, and two staple insertion sensors, one for each staple gun. Core assembly sensor means adjacent to the table senses the presence of the two sets of assembled cores on the plurality of supports in position to be fastened together. A control for operating the apparatus includes first control means operated by the core assembly sensor means to operate the actuators of each of the pair of movable carriers and move the plurality of automatically operated staple guns from their retracted positions to their staple insertion positions, second control means for operating each of the plurality of staple guns and inserting staples into the two sets of assembled cores to retain each of the water jacket cores and slab cores together in the sub-assembly, and a third means operated by the staple insertion sensors for operating the actuators for the pair of movable carriers to move the pair of movable carriers to the retracted positions. In the apparatus, the retracted positions of the pair of movable carriers are below the level of the table and the staple insertion positions locates the ends of the plurality of staple guns adjacent the sides of the water jacket core and slab core in such a position that the plurality of staples are inserted into the assemblies with one tine of each inserted staple being placed in the water jacket core and the other tine of the staple being inserted into the slab core with the crown of the staple lying across the interface between the water jacket core and slab core, retaining the water jacket core and slab core in their sub-assembly.
Other features and advantages of the invention will be apparent from the accompanying drawings and the more detailed description of the invention that follows.
The apparatus 10 is adapted to retain together two sets of assembled sand cores, each set including a water-jacket core and a slab core for a V-block of an internal combustion engine. As illustrated most clearly in
In the preferred embodiment illustrated in
The apparatus further includes a control 21 including first control means triggered by the core assembly sensor 20 for operating the plurality of actuators 15, 16 to move and locate the plurality of staple guns 14 in their staple insertion positions 14a. The control also includes a second control means for operating actuators for the staple guns 14 when the plurality of staple guns 14 have stopped at their staple insertion positions, and third control means triggered by signals from the plurality of staple sensors of the staple guns for operating the plurality of actuators 15, 16 and moving the plurality of movable carriers 12 and staple guns 14 to their retracted positions.
The plurality of carrier drivers 15, 16 can be any form of linear actuator, electric, hydraulic, or pneumatic, but preferably comprise air-operated piston-cylinders 15, 16 operated by said control with air valves (not shown) to move the staple guns vertically through the action of air-operated cylinders 16 and horizontally through the action of air-operated cylinders 15, to position the muzzle of the staple gun 14 directly against the assembled sand cores 13.
In the preferred apparatus of the invention illustrated in
As illustrated by
Thus, the invention provides an apparatus for automatically fastening together a plurality of assembled cores, such as a water jacket core and a slab core for an internal combustion engine block, including first means 11 for supporting the assembled cores in a predetermined fastening position, second means 20 for sensing the presence of the assembled cores at the predetermined fastening position, a plurality of third means 12 operated by the second means 20 for carrying a plurality of staple guns 14 between retracted positions and staple insertion positions adjacent the assembled cores 13, fourth means incorporated into the plurality of staple guns 14 operated by the second means 20 for operating the plurality of staple guns 14 when they have reached their staple insertions positions, and fifth means also incorporated into the plurality of sensor guns for sensing when the staples have been inserted from all staple guns 14 into the assembled cores 13 and for thereafter operating third means 12 returning the plurality of staple guns 14 to their retracted positions.
In one operation of the preferred production apparatus, two assemblies of water jacket cores and slab cores are formed and carried by a pick-and-place robot to a fastening apparatus 10. At the fastening apparatus 10, the two assemblies of sand cores are located by the pick-and-place robot and lowered onto a plurality of assembly supports 11b projecting upwardly from a table 11a. A core assembly sensor 20 senses the presence of the core two assemblies in proper location for fastening and operates a pair of movable carriers 12 by which a plurality of staple guns 14 are moved into location against the two core assemblies 13 for insertion of a plurality of staples into the water jacket cores and slab cores. Preferably, each fastener gun is an automatically operable staple gun, and is preferably positioned so that one tine of each staple is inserted into the water jacket core and the other tine of each staple is inserted into the slab core with the crown of the staple lying across the interfacing sides of the water jacket core and slab core to retain the assembled cores together. Upon completion of the fastening operation by insertion of all of the staples, the fastened assemblies 13 of core elements are removed from the plurality of supports by the pick-and-place robot for further processing.
The automatically operable staple guns preferably comprise Mezger's Stapling Head Part No. MEZ-A20-60 right hand and left hand, electronic staple sensor Part No. MEZ-Sensor-5, and electronic sensor conversion Part No. MEZ-VY63 PF. The two staple guns 14 on each movable carrier 12 are preferably spaced so that there is a distance of 12 inches between the staples inserted by each of the staple guns. While any form of sensor 20 can be used to sense the presence of the core assemblies in their fastening positions on the support 11, a proximity sensor that does not engage the core assemblies is preferred to reduce the risk of damage to the core assemblies.
Hoses, cables and other interconnections have been omitted from the
The foregoing description is to be regarded as illustrative, rather than limiting, and it will be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.
This patent application is a continuation-in-part of U.S. patent application Ser. No. 10/210,518, filed Aug. 1, 2002, which is hereby incorporated by reference.
Number | Date | Country | |
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Parent | 10210518 | Aug 2002 | US |
Child | 10954452 | Sep 2004 | US |