Abstract:
A power hammer assembly providing forming capabilities while remaining economical with respect to performance, vibration, footprint size and acquisition costs. The power hammer assembly can provide for a single stroke speed and/or a single set stroke with respect to the striking of die assemblies against a piece of metal. The power hammer assembly can provide for a large throat area and/or a larger die gap for ease of use. The power hammer assembly can include adjustment features allowing for the use of die sets of varying configurations such as, for example, shank size, shank length or alternatively, die sets fabricated for use with other machinery. In addition, the power hammer assembly can include a belt transmission assembly designed to slip in the event of die interference during set-up or operation so as to avoid damaging the power hammer assembly.

Description:
PRIORITY CLAIM  
       [0001]     The present application claims priority to U.S. Provisional Application No. 60/660,782, filed Mar. 11, 2005, and entitled, “METAL SHAPING APPARATUS,” which is herein incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The invention relates generally to the field of shaping metal. More particularly, the present invention pertains to a power hammer assembly capable of economically providing three-dimensional shaping capabilities.  
       BACKGROUND OF THE INVENTION  
       [0003]     A variety of methods and machines are presently available for shaping metal into three-dimensional parts. Recently, the popularity of such metal shaping methods and machines has been increased due to the number of television programs dealing with custom metal shaping in the context of motorcycle and automobile customization. As such, a new generation of potential customizers and users has been introduced to the art and skill of metalworking.  
         [0004]     Prior to the development of power machinery, metal forming and customization was accomplished through hand forming. Eventually, the development of controlled, powered machinery such as, for example, power hammers and forming machines available from companies such as Pullmax of Sweden and Eckold of St. Andreasberg, Germany, as well as those disclosed in U.S. Pat. No. 4,181,002 to Eckhold et al., U.S. Pat. No. 4,372,183 to Lehtinen and U.S. Pat. No. 6,427,515 to Kuhne, each of which is herein incorporated by reference in their entirety, provided metal workers with increased forming capabilities while decreasing production times.  
         [0005]     Unfortunately, using presently available power hammers and formers can subject users to a number of inherent disadvantages. Generally, presently available power hammers and formers are expensive and may cost on the order of tens of thousands of dollars putting them out of reach of all but the largest metalworking operators. Presently, available power hammers and formers tend to be bulky and occupy large footprints making them unsuitable for small-scale operations. In addition, presently available power hammers and formers can require precise, custom machined die sets, which may be unusable with other machinery, in order to provide proper operational clearance. Finally, presently available power hammers and formers can be operated by linkage drives that have the capacity to literally destroy the machines if proper die set-ups and clearances are not maintained.  
       SUMMARY OF THE INVENTION  
       [0006]     The present disclosure addresses a power hammer assembly providing users with the metal forming advantages associated with power machinery at a reduced expense and in a smaller footprint than presently available power hammer systems. In general, the power hammer assembly of the present invention provides three-dimensional shaping capabilities, which have application in the forming of custom metal products such as, for example, customized motorcycle and automotive parts. The power hammer assembly of the present disclosure can be fabricated and assembled in a kit fashion with commonly available tools to reduce costs. Alternatively, the power hammer assembly of the present disclosure can be purchased in an assembled configuration.  
         [0007]     In one aspect, a power hammer assembly of the present disclosure provides powered forming capabilities while remaining economical with respect to performance, vibration, footprint size and acquisition costs. In some embodiments, the power hammer assembly can comprise a power assembly for providing a single stroke speed and/or a single set stroke with respect to the striking of die assemblies against a piece of metal. In some embodiments, the power hammer assembly of the present invention can comprise a larger throat area and/or a larger die gap than presently available power hammers to facilitate ease of use. In some embodiments, the power hammer assembly of the present invention can comprise adjustment features allowing for the use of die sets of varying configurations such as, for example, shank size, shank length or alternatively, die sets fabricated for use with other machinery. In some embodiments, the power hammer assembly of the present invention can comprise a belt transmission assembly designed to slip in the event of die interference during set-up or operation so as to avoid damaging the power hammer assembly. In some embodiments the power hammer assembly of the present invention includes fine adjustment means for spacing between the upper and lower die.  
         [0008]     In another aspect, a method of forming metal pieces with a power hammer assembly is disclosed and described.  
         [0009]     In yet another aspect, the present disclosure relates to a kit for fabrication and assembly of a power hammer assembly using commonly available tools and tooling.  
         [0010]     The above summary of the various representative embodiments of the disclosure is not intended to describe each illustrated embodiment or every implementation of the invention. The figures in the detailed description that follow more particularly exemplify these embodiments. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:  
         [0012]      FIG. 1  is a perspective view of an embodiment of a power hammer assembly.  
         [0013]      FIG. 2  is an exploded, perspective view of the power hammer assembly of  FIG. 1 .  
         [0014]      FIG. 3  is an exploded, perspective view of the power hammer assembly of  FIG. 1 .  
         [0015]      FIG. 4 a  partially hidden, side view of the power hammer assembly of  FIG. 1 .  
         [0016]      FIG. 5  is partially hidden, top view of the power hammer assembly of  FIG. 1 .  
         [0017]      FIG. 6  is a partially hidden, front view of the power hammer assembly of  FIG. 1 .  
         [0018]      FIG. 7  is a partially hidden, rear view of the power hammer assembly of  FIG. 1 .  
         [0019]      FIG. 8  is a perspective view of the power hammer assembly of  FIG. 1  mounted on a portable stand for shaping a piece of metal.  
         [0020]      FIG. 9  is a perspective view of the power hammer assembly of  FIG. 3  shaping a piece of metal.  
         [0021]      FIG. 10  is a perspective view of a die holder portion of the power hammer assembly of  FIG. 1 .  
         [0022]      FIG. 10   a  is an enlarged perspective view of the die holder portion of the power hammer assembly taken at Detail A of  FIG. 10 .  
         [0023]      FIG. 11  is a perspective view of an embodiment of a dual work zone power hammer assembly. 
     
    
       [0024]     While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]     As illustrated in  FIGS. 1, 2 ,  3 ,  4 ,  5 ,  6 ,  7 ,  10  and  10   a , a power hammer assembly  100  of the present invention provides the ability to shape metal with a reduced footprint, vibration-free power tool. With reference to  FIG. 1 , power hammer assembly  100  generally comprises a body assembly  102 , a forming die portion  104 , a die adjustment portion  106 , a motor portion  108  and a belt transmission portion  110 . Power hammer assembly  100  can be fabricated so as allow assembly with the use of suitable fasteners  111  such as, for example, screws.  
         [0026]     As shown in detail in  FIGS. 2 and 3 , body assembly  102  comprises a pair of support base assemblies  112   a ,  112   b , a pair of side plates  114   a ,  114   b , a pair of base spacers  115  and a shroud cover  116 . Forming die portion  104  comprises a pair of die holders  118   a ,  118   b , a female shrinking die  120  and a male shrinking die  122 . Female shrinking die  120  and male shrinking die  122  can comprise machined, hand polished hardened steels such as, for example, 4140 hardened steels. Female shrinking die  120  and male shrinking die  122  can comprise shanks such as, for example, 0.75″ by 0.75″ square shanks, for attaching the female shrinking die  120  and male shrinking die  122  to the die holders  118   a ,  118   b . Die adjustment portion  106  comprises an adjustment wheel  124 , an adjustment rod  126 , an adjustment sleeve  128 , a sleeve cross bolt  129  and an adjustment collet  130 . Motor portion  104  can comprise an electric motor  132  having a power cord assembly  133  as shown in  FIG. 8 . In one representative, presently preferred embodiment, electric motor  132  can comprise a one horsepower,  115  VAC, single-phase motor allowing for convenient electrical hookup to typical residential and commercial power sources. Belt transmission portion  110  can comprise a belt cover  134 , a belt cover lid  136 , a top pulley  138 , a bottom pulley  140 , a belt  142 , a rear spacer plate  144 , a pair of flange bearings  146 , an offset shaft  148 , a front mount plate  150 , a connecting rod  152 , a bearing  153 , a slider  154 , a bushing  155 , a top collet  156 , a bushing  158 , a slide guide  160 , an alignment key stock  162  and a support key stock  164 . Bottom pulley  140  is adapted for slidable placement and fixation over the motor shaft  166 .  
         [0027]     Female shrinking die  120  and male shrinking die  122  are disclosed and described for illustration purposes only as one of skill in the art will recognize that a variety of alternative die set designs can be employed with the present invention. Representative, alternative die set designs can comprise stretching die sets, beading die sets, flanging die sets, doming die sets, plannishing die sets and flaring die sets. During use, die sets are routinely changed out based on the desired shape to be formed. By selectively configuring adjustment collet  130  and top collet  156 , dies sets having alternative shank sizes such as, for example, 0.375″ by 0.375″, 0.5″ by 0.5″ and 0.625″ by 0.625″ (as well as various metric sizes), can be utilized with power hammer assembly  100 . Furthermore, spacers such as, for example, an L-shaped spacer can be used to adjust the configuration of adjustment collet  130  and top collet  156 .  
         [0028]     As illustrated in  FIGS. 8 and 9 , power hammer assembly  100  can be assembled and placed on a portable stand assembly  168  to form a portable power hammer assembly  170 . Portable stand assembly  168  can comprise a mounting element  172 , stand legs  174 , support member  176  and a plurality of caster assemblies  178 . Using support base assembly  112 , power hammer assembly  100  can be fixedly mounted to mounting element  172  such that a user can rollingly position the portable power hammer assembly  170  in a variety of locations for use and/or storage. In addition, when a  115  VAC, single-phase electric motor  132  is used, portable power hammer assembly  170  can be positioned anywhere  115  VAC power is available.  
         [0029]     Referring to  FIG. 4 , power hammer assembly  100  comprises a fabrication area  180  defined by a throat depth  182  and a die opening  184 . In one presently preferred embodiment, throat depth  182  comprises about an eighteen-inch depth providing power hammer assembly  100  the capacity to shape the middle of a thirty-six inch metal panel. Die opening  184  in one presently preferred embodiment is adjustable configurable through the use of die adjustment portion  106  from a maximum opening of about 6 inches to a minimum of about 0.5 inches. Die adjustment portion  106  provides power hammer assembly  100  with an infinitely adjustable lower die holder  118   b . Adjustment rod  126  has a continuous thread such that lower die holder  118   b  and consequently, male shrinking die  122  can be adjustably lifted upwards toward the female shrinking die  120 , through hand rotation of the adjustment wheel  124 , to set the proper die opening  184 . By providing an infinitely adjustable die adjustment portion  106 , die holders  118   a ,  118   b  do not require machining to exact lengths such that die holders contemplated for and used with other machines can be interchangeably used with power hammer assembly  100 .  
         [0030]     When fully assembled, power hammer assembly  100  is capable of shaping metal such as, for example, shrinking metal through the multiple stamping operations as depicted in  FIGS. 8 and 9 . For example, using a one horsepower electric motor  132 , female shrinking die  120  and male shrinking die  122  can be hit at a hit rate of about 900 hits per minute. Based on the desired three-dimensional shape to be formed, a user selects an appropriate die set such as, for example, female shrinking die  120  and male shrinking die  122 . Once female shrinking die  120  and male shrinking die  122  have been attached to their corresponding die holder  118   a ,  118   b , a user positions the piece of metal to be formed within the die opening  184  between the female shrinking die  120  and male shrinking die  122 .  
         [0031]     The user initiates operation of the power hammer assembly  100  by plugging in power cord assembly  133  and actuating a power actuator such as, for example, a pushbutton or switch assembly  186  as shown in  FIG. 8 . When switch  186  is in an operational position, electric motor  132  causes motor shaft  166  to begin rotating wherein bottom pulley  140  begins turning the driving belt  142 . As driving belt  142  is rotated, top pulley  138  spins, which correspondingly provides, axial rotational motion to offset shaft  148 . As offset shaft  148  spins, connecting rod  152  translates the rotational motion to a vertical, reciprocating motion wherein an up and down stamping motion is translated to female shrinking die  120  through slider  154 . Depending upon the gauge of a metal sheet  300  being formed, the user turns adjustment wheel  124  to lift the male shrinking die  122  so as to define the appropriate die opening  184 . As the metal sheet  300  is conformed to the selected die set such as, for example, female shrinking die  120  and male shrinking die  122 , the metal sheet  300  assumes the desired three-dimensional shape such as, for example, custom motorcycle components such as a gas tank or fender  302  as illustrated in  FIG. 9 . In the event that the female shrinking die  120  and male shrinking die  122  interfere during operation or set-up, the belt transmission portion  110  causes belt  142  to slip so as to avoid damage to the power hammer assembly  100 .  
         [0032]     Upon completion of a desired forming operation, portable power hammer assembly  170  can have power cord assembly  133  unplugged such that caster assemblies  178  can be used to rollably position the portable stand assembly  168  in a desired storage position allowing the user to avoid permanently occupying work space.  
         [0033]     An alternative, representative embodiment of a dual work zone power hammer assembly  200  is illustrated in  FIG. 11 . Dual work zone power hammer assembly  200  can substantially resemble power hammer assembly  100  with the exception that dual work zone power hammer assembly  200  comprises both a first forming die portion  202  and a second forming die portion  204 . First forming die portion  202  and second forming die portion  204  can be actuated and operated so as to allow for simultaneous shaping operations or alternatively, first forming die portion  202  and second forming die portion  204  can comprise selected die sets such as, for example, female shrinking dies  120  and male shrinking dies  122 , so as to allow a first forming operation in the first forming die portion  202  and a second forming operation in the second forming die portion  204 . Both dual work zone power hammer assembly  200  and power hammer assembly  100  can comprise a direct current variable speed drive  206  so as to provide the capability for controlling the strike rate of the dies sets such as, for example, reducing the rate of die strikes.  
         [0034]     The present disclosure describes aspects of one presently preferred embodiment of a power hammer assembly for economically providing three-dimensional metal shaping capabilities. It will be understood by one of skill in the art that additional, alternative embodiments are contemplated and would not depart from the spirit and scope of the present disclosure.