Abstract:
An apparatus for attaching shaped metal clips at intervals to viscous-product-filled casing includes a support frame, a clipper assembly, a clipper assembly mounting rail, and a clipper assembly reciprocation mechanism. The clipper assembly is reciprocally mounted for reciprocal movement back and forth between a first casing entry station and a second casing exit station. A continuous tube of filled casing enters the apparatus at the first station and exits at the second station. The clipping assembly includes a filled casing support passage. Filled casing is directed through this passage as the casing extends between the first and second stations. The clipper assembly further includes first and second casing gathering plates which are projectible into the passage to gather the filled casing to form a neck section therein. The neck section is for attachment of at least one clip about the casing. In the region between the first and second stations, the tube of casing is clipped by the reciprocating clipper assembly, which further includes a clipper mechanism for attachment of clips about the gathered casing.

Description:
This application claims the benefit of provisional applications 60/102,826 filed Oct. 2, 1998 and 60/107,429 filed Nov. 6, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to apparatus for attachment of U-shaped metal clips to a tube of flexible casing material which has been filled with a viscous product. The apparatus applies clips to the casing as the filled casing-product is moving. The invention further relates to a mechanism for attaching metal clips to casing at intervals along the casing thereby sealing product within the casing in the form of separate links as the filled casing is moving continuously. 
     Various food products, such as sausage or cheese, are packaged in flexible, tubular casing by attaching metal clips to the filled casing at spaced intervals thereby sealing and closing the product within the casing, Klenz, U.S. Pat. No. 3,383,754 issued May 21, 1968. incorporated herewith by reference, discloses a device adapted for applying U-shaped metal clips about casing. Klenz discloses the use of a punch for driving a U-shaped metal clip through a channel against a die to form the clip about filled and gathered casing material aligned between the punch and the die. Klenz, U.S. Pat. No. 3,543,378 discloses the use of a pair of clippers arranged in tandem and cooperative with opposed, moveable, casing gathering plates defining a pair of clip channels. The gathering plates move in opposition to each other to gather filled casing material into a constricted form. Two U-shaped metal clips are then driven in channels defined by the gathering plates by punches about the gathered material to seal the ends of adjacent links of the casing. A knife then cuts the casing between the clips to separate the links defined by the clipped casing. 
     Other patents disclose various combinations of gathering mechanisms for gathering casing prior to attachment of the clip or clips, including Klenz U.S. Pat. No. 3,583,506; Dobbert, U.S. Pat. No. 3,783,583; and Velarde, U.S. Pat. No. 4,001,926. 
     Various mechanisms have been suggested for improving the efficiency and speed of operation of clipping mechanisms when forming links of product in a continuous or assembly line operation. Andre, U.S. Pat. No. 3,795,058 discloses a single clipper mounted at a work station of rotating table. The table moves intermittently from station to station between operations performed at each station, including a clip attachment station. Andre, U.S. Pat. No. 4,578,928 discloses a circular table wherein filled casing material is transported from station to station for ultimate attachment of the clip. Ailey, U.S. Pat. No. 4,189,897, discloses a similar multiple station apparatus. 
     Evans et al., U.S. Pat. No. 4,821,485 disclose apparatus for attaching clips to form separate links in an operation wherein the filled casing is continuously moving in a circular pattern with the filed casing being gathered and clipped as the product and casing move continuously by and through the apparatus. The various operational stations move with the casing in a continuous circular motion about a center pivot and the various gathering and clipping operations are performed as the apparatus rotates about the pivot in a single direction. 
     The need has remained for a high speed continuously operating packaging device for attachment of metal clips to flexible, generally cylindrical, continuously moving casing filled with a viscous material. Such a need has been considered desirable to form links of various diameter and length filled with various materials in a continuous operation. 
     SUMMARY OF THE INVENTION 
     In a principal aspect, the present invention is an improved mechanism for sealing filled and continuously moving casing in discreet links or lengths. The apparatus includes a frame on which a reciprocating clipper assembly is mounted. The clipper assembly reciprocates continuously back and forth between a first or casing entry station and a second or casing exit station. Flexible casing, which has been prefilled with viscous material, enters the apparatus at the first station and is discharged from the second station. In the region between the first and second stations, the clipping assembly is designed to reciprocate at the same speed or synchronously with the rate of movement of the filled casing material moving forward between the first and second stations. 
     As the clipper assembly moves forwardly with the filled casing material, it effects gathering of the casing in order to form a necked portion thereof. The gathering operation includes voiding of a certain portion of the casing by and between a pair of gathering plates which initially constrict the casing and the separate to void the viscous filling material in the casing from the region of the constriction. The gathering plates separate or spread to ensure that a length or tail of constricted or necked casing is provided. 
     A pair of spaced, U-shaped metal clips is then applied to the necked casing by clipper subassemblies which are positioned intermediate the spaced gathering plates. The clips are applied simultaneously by the clipper subassemblies to the necked casing “on the fly” as the casing and clipper assembly move between the first and second stations. Thereafter, optionally, the clipper assembly effects a cut or severance of the casing between the attached metal clips so that separate links are formed. The filled casing, having the clips attached thereto, is next released at the second station. 
     The clipping assembly then reciprocates or moves in the reverse direction from the second station back to the first station without impeding the continuous forward movement or progress of the filled casing between the first and second stations. Upon arrival at the first station, the clipper assembly again begins its synchronous movement with the filled casing to effect attachment of further clips thereto. 
     Thus, it is an object of the invention to provide an improved packaging device for filling flexible tubular casing filled with a viscous material. 
     A further object of the invention is to provide an improved packaging device with apparatus for attachment of U-shaped metal clips to flexible tubular casing. 
     Yet another object of the invention is to provide a continuously operating packaging device adapted to receive tubular casing material filled with a viscous product as that filled casing moves uninterruptedly and continuously in a generally linear direction. 
     Yet another object of the invention is to provide a clipper assembly which reciprocates between an entry station and an exit station and, which during movement from the entry station to the exit station, effects voiding of a section of the filled casing and attachment of one or more clips thereto. 
     Yet another object of the invention is to provide a packaging device which is capable of manufacture of a wide range of lengths of link product. 
     Another object of the invention is to provide an improved clip attachment mechanism having simplified construction and which is compact, yet which permits extremely high speed operation relative to prior art packaging devices: 
     These and other objects, advantages and features of the invention All be set forth in the detailed description which follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     In the detailed description which follows reference will be made to the drawing comprised of the following figures: 
     FIG. 1 is an isometric view of the apparatus of the invention; and 
     FIG. 2 is an isometric view of the internal construction of the gathering plates used in the apparatus of the invention. 
     FIG. 3 is a front elevation of the apparatus of the invention; 
     FIG. 4 is an isometric view of the apparatus of the invention; 
     FIG. 5 is a side elevation of the apparatus of the invention; 
     FIG. 6 is an isometric view of the clipper of the invention and the reciprocal mounting bars for the clipper; 
     FIG. 7 is a front elevation of the clipper of FIG. 6; 
     FIG. 8 is a top plan view of the clipper assembly of FIG. 6; 
     FIG. 9 is a side elevation of the clipper assembly of FIG. 6; 
     FIG. 10 is an isometric view of the total packaging apparatus wherein the clipper assembly is incorporated therewith without the guard frame; 
     FIG. 11 is an isometric view of the gathering, voiding and clip attachment assembly of the apparatus viewed from the downstream side of the assembly; 
     FIG. 12 is an isometric view of the assembly of FIG. 11 viewed front the opposite or upstream side; 
     FIG. 13 is a cutaway isometric view of the assembly of FIG. 11 viewed along the plane  13 — 13  in FIG. 11; 
     FIG. 14 is a cutaway isometric view of the assembly of FIG. 11 viewed along the plane  14 — 14  in FIG. 11; 
     FIG. 15 is a cutaway isometric view of the upper clipper subassembly of FIG. 11; and 
     FIG. 16 is an exploded isometric view of the lower clipper or clipper anvil subassembly of FIG.  11 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 depict a frame  10  which supports a dual rail comprised of first and second, or upper and lower horizontal, spaced rail bars or rods  12  and  14 . A clipper assembly  16  is reciprocally mounted on the rods or bars  12  and  14  (FIG. 6) and is powered to reciprocate between a first or entry station adjacent a first vertical support beam  18  of frame  10  and a second or exit station adjacent a second vertical support beam  20 . Previously product filled, flexible, casing  22  continuously moves between the first and second stations in the forward direction indicated by the arrow and extends or fits through a passage or opening  24  of the clipper assembly  16 . The casing  22  is filled in a separate apparatus such as depicted and/or discussed in the prior art patents referenced above, all of which are incorporated herewith by reference. 
     As the casing  22  moves continuously in the forward direction as described, the clipper assembly  16  is driven by a reciprocating drive piston assembly or actuator  46  and reciprocates between the first or entry station, and the second or exit station moving either forward synchronously with casing  22  or in the opposite direction. Movement and operation of assembly  16  is controlled by a control mechanism retained in the control box  26 . The clipper assembly  16  moves from the first station to the second station synchronously with the movement of the casing  22  as the casing  22  is necked, voided and a clip or clips  28 ,  30  are attached. After clips  28 ,  30  have been attached to the casing  22 , the clipper assembly  16  will release the casing and reciprocate to the first station from the second station by movement opposite to the movement of the casing  22 . The assembly  16  may then repeat its sequential operation and move synchronously once again with the movement of the casing  22  for gathering and attachment of yet a further clip or set of clips, subsequent release and then reverse movement. 
     As shown in FIG. 1, a pair of U-shaped metal clips  28 ,  30  of the type depicted in the prior art references referenced above are attached to the casing  22  at discrete length intervals to form links in the casing  22 . First, however, gathered casing  22  is formed or gathered to form a tight neck, for example, neck  32 . After the neck  32  is formed, the clips  28  and  30  are applied thereto. The casing  22  intermediate the clips  28  and  30  may be severed by means of a knife  29 . In this manner, the casing  22  may be cut into separate links. 
     In review, prior to attachment of clips  28  and  30 , gathering plates, such as gathering plates  94   96 ,  102 ,  104  in FIGS. 2,  13 ,  14  engage the casing material  22  to form the neck  32  and to void a portion of the casing  22  of material filling the casing in the neck  32 . The plates  94 ,  96 ,  102 ,  104  then separate slightly during movement in the direction of casing  22  movement to define a length of the necked section  32 . One or more clips  28 ,  30  may then be attached to the neck or necked portion  32  by means of a clipper  38 . An important feature of the invention is the mechanism associated with the plates  94 ,  96 ,  102 ,  104 . The mechanism provides that the plates  94 ,  96 ,  102 ,  104  will cause the necking of the casing  22  and voiding of material from the casing  22  in the region where it is necked. 
     The sequence of operations of the clipper assembly  16  includes initial movement of the entire assembly  16  synchronously forward with the casing  22 , followed by operation of the gathering plates  94 ,  96 ,  102 ,  104  to gather and void the casing  22  and to then separate so as to define a neck  32 . Thereafter, the clipper  38  operates to place two spaced U-shaped metal clips  28 ,  30  about the casing  22  to seal the ends of separate links of the casing  22 . Thereafter, and optionally, a knife  95  may sever the casing  22  between the applied clips  28 ,  30  and through the neck  32 . Thereafter, the knife  95 , the clipper  38 , and the gathering plates  94 ,  96 ,  102 ,  104  are released from the casing  22  and the clipper assembly  16  is traversed back to the first station with the filled casing  22  sliding through the passage  24  in the clipper assembly  16 . While at the first station, the clipper assembly  16  may dwell so that the length of filled casing  22  passing through the assembly  16  will be as desired to form an appropriate length of link. The movement of the assembly  16  may then be commenced and the operation of attachment of a clip or clips  28 ,  30  is repeated. 
     Apparatus of the type described have been developed to provide for a cycle time of assembly  16  movement between the first and second stations of 1.5 seconds thereby resulting in extremely fast, operation relative to prior art, operations. Moreover, the apparatus of the invention is especially compact relative to the prior art constructions. 
     Referring again to the figures, frame  10  is comprised of first and second vertically upstanding spaced support beams  18  and  20 . The support beams  18  and  20  are connected by horizontal cross members  13  and  15  to thereby define a support for slide bars  12 ,  14  that support the reciprocating clipper assembly  16 . The entire construction is typically retained in a housing  31  such as depicted in FIG. 3 comprised of enclosing panels. The housing  31  includes an entry end panel  33  into which filled casing  22  is inserted through an inlet passage  35 . An exit passage (not shown) in the opposite outside panel of the housing  31  is provided for discharge of filled casing  22 . An observation opening or window  37  is provided in the front of the housing  31 . The entire construction may be mounted on a wheeled carriage (not shown) and may be constructed so that beams  18 ,  20  telescope to be movable in the vertical direction in order to align the casing inlet  35  appropriately with the discharge outlet from a product filling machine, for example. 
     Referring to FIG.  8  and FIG. 9, the clipper assembly  16  is slidably mounted on the rail rods  12  and  14 . The assembly  16  is driven reciprocally back and forth on rail rods  12 ,  14  by means of a reciprocal actuator  46 . The actuator  46  may be hydraulic, pneumatic or otherwise. The actuator  46  connects with the assembly  16  by means of a bracket  41  which is driven horizontally back and forth by actuator  46  in response to control signals from control box  26 . 
     The clipper assembly  16  further includes a first clipper  34  and a second clipper  36 . Clips  28 ,  30  are fed through channels  39  and  40  respectively to be driven by a punch  43  against an anvil  44 . The punch  43  and anvil  44  are driven by means of a piston assembly  38  to attach the clips  28 ,  30  to casing material  22  passing through the assembly  16 . Gathering plates (described below) are associated with gathering blocks carried on the assembly  16 . The plates close or clamp upon casing material  22  passing through the assembly to form a constricted neck. Then the blocks separate one from the other through an eccentric or another mechanism driven by a motor or piston  52  so as to provide an elongated neck in the casing  22 . 
     FIGS. 11-15 illustrate in greater detail the construction of the clipper assembly  16  which is reciprocally mounted on the rods  12  and  14  for horizontal, reciprocal motion between the stations between the vertical frame support members  18  and  20 . FIG. 11 depicts a downstream isometric view of the clipper assembly  16 . FIG. 12 depicts an upstream side of the clipper assembly  16 . FIG. 13 is a cutaway isometric view depicting the movable voider assembly and blocks. FIG. 14 is an isometric view depicting the stationary voider assembly and blocks. FIG. 15 is an isometric view of an upper clipper subassembly associated with the punches which drive clips down channels against an anvil to form the clips  28 ,  30  about the gathered casing  22 . FIG. 16 is an isometric view, of a lower anvil subassembly of a lower clipper assembly. 
     Referring first, therefore, to FIGS. 11 and 12, the clipper assembly  16  is comprised of a movable voider assembly  60  which is opposed to a fixed voider assembly  62 . The voider assemblies  60  and  62  are arranged in opposed facing relationship and are movable with respect to one another between a position wherein the moveable assembly  60  is positioned tightly against the fixed assembly or immovable assembly  62  and a position wherein the assemblies  60 ,  62  are spaced from one another following their gathering and necking operations. 
     The clipper assembly  16  further includes a lower clipper anvil subassembly or mechanism  64  (FIG. 16) and an upper clipper subassembly  66  (FIG.  15 ). Rails  68 : are provided on opposite sides of the assembly as shown in FIG. 11 and 12 feeding clips into the clipper assembly  16 . The described assemblies and subassemblies are all mounted on a bracket comprised of spaced vertical plates  70  and  72  connected together by horizontal connecting plates  74  and  76 . The plates  70 ,  72 ,  74  and  76  thus form a rigid bracket, frame or structure  77  upon which the stationary and movable voider assemblies  60  and  62 , as well as the lower clipper subassembly  64  and upper clipper subassembly  66  are mounted. The stationary voider assembly  62  is rigidly mounted to the described structure. The movable voider assembly  60  is movable within the bracket  77  so as to be movable between a first position immediately adjacent the stationary voider assembly  62  and a spaced position relative to the stationary voider assembly  62 . The lower and upper clipper subassemblies  64  and  66  are rigidly attached to the described bracket  77  and do not move relative to other component parts, although the upper clipper assembly  66  includes clip channel plates and punches which move to drive clips from the rails  68  into engagement with moveable anvils associated with the lower clipper subassembly  64 . Thus, lower subassembly  64  will position an anvil appropriately relative to gathered and necked casing for engagement with clip  28 ,  30  drive by punches through clip channel plates. 
     FIG. 13 depicts the movable voider assembly in an isometric view sectioned in a manner to illustrate the internal or inside of the voider assembly  60 . That is, the voider assembly  60  includes cylinders  80  and  82 , each with a piston connected respectively to blocks  84  and  86  by means of a rod. This enables the blocks  84  to move simultaneously, equally and reciprocally back and forth in the direction depicted by the arrow in FIG.  13 . The blocks  84  and  86  also include transverse cylinders which include rods  90  and  92  connected with gathering plates  94  and  96  respectively. The plates  94  and  96  may be driven toward or away from each other as depicted by the arrows on block  86  in FIG.  13  and block  84  in FIG.  13 . The plates  94 ,  96  include shaped openings, such as opening  98 , through which filled casing  22  may be inserted. The shaped openings  98  have a narrow or V-shaped end such as end  100  of plate  96 . The separate plates  94 ,  96  each have the described shape and the narrowed ends  100  so that when the plates  94 ,  96  are separated or moved horizontally, the narrowed ends  100  will come together and gather material inserted through the opening  98  defined by the plates  94 ,  96 , thereby forming a neck in the casing material  22  in that opening  98 . 
     FIG. 14 depicts the construction of the stationary voider assembly which is substantially a mirror image of the construction depicted in FIG. 13 associated with the movable voider assembly. Thus, the stationary assembly includes gathering plates  102  and  104  which include an opening  106  that is closed by actuation of driver blocks  108  and  110  to constrict casing material  22  passing through the opening  106 . Blocks  108 ,  110 , however, do not move relative to bracket  77 . 
     In operation, the casing material  22  is passed through the openings  98  in plates  94 ,  96 ,  102  and  104 . The plates  94 ,  96 ,  102 ,  104  are then driven in a horizontal direction towards one another to constrict the opening defined by the plates  94 ,  96 ,  102  and  104  along the center line through the passage  24  of assembly  16  uniformly about the center line of opening  24 . This effects gathering of the casing material  22 . 
     The movable voider assembly  60  is then actuated by operation of the cylinder and pistons  80 ,  82  to separate the assembly  60  including plates  94 ,  96  from adjacent the plates  102 ,  104  in the direction of casing movement thereby necking the casing material  22  and voiding a portion or length of the casing material  22  as the plates  94 ,  96  separate or become spaced from the plates  102 ,  104 . The plates  94 ,  96 ,  102  and  104  are thus immediately adjacent one another initially and are also in their full open or overlapping position such as illustrated in FIGS. 13 and 14. Casing material  22  is then inserted through the opening  98  defined by the plates  94 ,  96 ,  102 ,  104 . The plates  94 ,  96 ,  102  and  104  are then driven in a manner so that they slide relative to one another in a direction transverse to the center line of the casing material  22 . This necks or narrows the casing material  22 . The plates  94 ,  96  are then driven or moved in the same direction as the axis of the casing  22  to separate longitudinally from plates  102 ,  104 . This effects the necking operation. 
     Thereafter, the lower clipper subassembly  64  positions an anvil  44  between the spaced plates  94 ,  96 ,  102  and  104  of the respective voider assemblies  60 ,  62  while simultaneously the upper clipper subassembly  66  drives spaced clips  28 .,  30  against the anvil  44  to attach the clips  28 ,  30  about to gather casing material  22 . As shown in FIG. 15, the upper subassembly includes a drive cylinder  114  mounted on a mounting bracket  116 . The drive cylinder drives clips  28 .  30  down channels  118  and  120  about gathered casing material  22 . Note that the channels  118  and  120  are formed in separate, spaced plates  122  and  124  which are transported adjacent anvil  44  before clips  28 ,  30  are attached. This also enables a cylinder  126  to operate a knife blade  128  to drive the blade  128  into the space between the plates  122  and  124  so as to sever casing  22  about which the clips  28 ,  30  have been placed. 
     The anvil  44  is thus positioned in an opposed relationship to the clip channels  118 ,  120  associated with the upper clip subassembly  66 . In other words, the lower clipper subassembly  64  moves anvil  44  into position immediately adjacent the center line axis of the casing material  22  in the assembly  16 . Simultaneously, the upper clipper subassembly  66  is operated to move the separate plates  122  and  124  in position with respect to the anvil  44  to define clip channels  118 ,  120  in which separate punches then move to drive clips  28 ,  30  through those channels  118 ,  120  into engagement with the anvils  44  and around the neck portion of casing material  22 . By the time, or when, the various assemblies and subassemblies reach the second station, all of the described elements are retracted from the center line axis of the casing material  22  and the casing  22  has been optionally severed so that the casing material  22  may continue to move in an uninterrupted fashion through the apparatus and further so that the clipper assembly  16  may move in the reciprocal direction to the first station for repeat of its cyclical operation. 
     It is contemplated that various types of clipper mechanisms may be used in conjunction with the described apparatus. Among the important features of the assembly, however, is the maintenance of the various gathering plates, anvil punches, etc. in alignment and moveable so as to maintain necking of the casing material  22  and attachment of clips  28 ,  30  thereto along a center line axis of the casing material  22  as it passes through the apparatus. Smooth and efficient movement of the casing, material through the apparatus is thus promoted without undue stress on the casing material  22  as it is being gathered and clips are being attached thereto. 
     Various alternative embodiments of the invention are considered to be within the scope of the invention which is limited only by the following, claims and equivalents thereof.