Abstract:
An article ejector is provided having kinematic linkages that drive ejector paddle assemblies in an article ejector mode, as well as a die cleaning mode where the kinematic linkages are driven via rotary motion in a continuous clockwise direction, in both modes, without having to impart changes in direction for the rotary drive mechanisms, and while maintaining maximum mechanical advantage of the kinematic linkages. A method is also provided.

Description:
RELATED PATENT DATA 
     This application claims priority from U.S. Provisional Patent Application Ser. No. 60/480,145, which was filed on Jun. 20, 2003, and which is incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     This invention pertains to apparatus for separating and ejecting thin-walled articles from a sheet of thermoformable plastic material in which the articles have been formed using a thermoforming press. More particularly, the present invention relates to a trim press article-ejecting apparatus, such as an article, or product, ejector. 
     BACKGROUND OF THE INVENTION 
     Numerous techniques are known for separating thin-walled thermoformed articles from sheets of thermoformable plastic material. The trimming of thermoformed articles from a continuous web or sheet of thermoformable plastic material has long been known in the art. It has been known to form and sever articles from webs of both solid and foamed-plastic material. 
     Using a thermoforming process, articles are molded into a heated material web using a thermoforming machine. A heated web of material is transported through the thermoforming machine where articles are then formed in the web. The web is then transported from the thermoforming machine at a relatively high operating speed into a trim press where the articles are severed from the web of plastic material. 
     Typically, a trim press includes cooperating male and female members, each member having cooperating cutting surfaces, such as complementary punches and dies that correspond with an outer configuration of the formed articles. Such pairs of punches and dies are adapted to cooperate and trim individual articles from the web as they are brought together on opposite sides of the web by the trim press. Recently, attempts have been made to further increase the operating speed of trim presses. Such increases in operating speed can lead to significant increases in throughput and article output. Accordingly, relatively high-speed trim presses have been developed that generate a continuous horizontally-nested stack of articles which are slid onto a platform, or packing table. However, increases in operating speed have caused some problems in that a vacuum is created when drawing apart platens of a trim press which can actually suck severed articles or scrap web material back up into the trim press dies, which can create a jam or problem when running the trim press at relatively high operating speeds. 
       FIGS. 7–8  illustrate one prior art solution in the form of an article accumulator  250  that is mounted onto a trim press similar to the trim press depicted with reference to  FIG. 1  wherein article ejector  250  substitutes for the new article ejector that is described with reference to  FIGS. 1–6  and  9 – 11 , as described in the Detailed Description, below. For the case of the prior art article ejector  250 , a support frame  252  is secured to a top face of an upper platen (not shown), such as the upper platen depicted with reference to  FIGS. 1 and 2 . Support frame  252  is secured via four mounting blocks  336 ,  338 ,  340 , and  342  via threaded fasteners. A pair of vertical die posts  312  and  314  are also supported within the upper platen via fastener collars  332  and  334 . Die posts  312  and  314  are rigidly and vertically secured within the upper platen. An ejector bridge  310  is supported by a bushing assembly  316  and  318  at each end for vertical up and down reciprocation along die posts  312  and  314 . A plurality of ejector paddle assemblies depend downwardly from ejector bridge  310 , such as ejector paddle assembly  344 , for ejecting articles that are severed between male and female dies of a trim press into an accumulator cavity, where the articles are stacked and accumulated for delivery to a conveyor. 
     According to the construction of prior art article ejector  250 , a servo motor  262  drives a drive pulley  320  which further drives a driven pulley  324  via a timing belt  330 . Driven pulley  324  is rigidly affixed onto a drive shaft  308  in order to drive a driven wheel  322  at its opposite end. Wheel  322  and pulley  324  each pivotally support one end of a crank arm  326  and  328 , respectively. Crank arms  326  and  328  are fixed with bearings at opposite ends to mounting positions on ejector bridge  310  so as to drive ejector bridge  310  and paddle assemblies  344  up and down so as to eject and clear product from between dies of a trim press during operation. 
     As shown in  FIG. 7 , support frame  252  includes side plates  300  and  302  which are joined together via rigid cross-shafts  304  and  306 . 
     Article ejector  250 , according to prior art techniques, is run in two operating modes. First, article ejector  250  is normally run to downwardly press (or eject) severed articles from dies and into a stack within an article accumulator (not shown). During such normal operating mode, pulley  324  and wheel  322  are driven between a 12:00 o&#39;clock and 3:00 o&#39;clock position by driving drive pulley  320  back and forth in clockwise and counter-clockwise directions, respectively, via operation of servo  262 . Accordingly, crank arms  326  and  328  are only driven to half their maximum displacement position as dictated by the attachment points in the diameters on wheel  322  and pulley  324 . 
     Another operating mode is desired in order to eject plastic material or damaged articles when there has been a misfeed or jam in a trim press. During such an operating mode, it is desirable to more deeply and fully stroke paddle assemblies into the female bores beneath a female die to eject any waste or damaged articles or material to clean out the trim press dies and cavities. In order to achieve such a result, the prior art techniques provided by article ejector  250  require operation of servo motor  252  to drive wheel  322  and pulley  324  between the 12:00 o&#39;clock and 6:00 o&#39;clock positions by driving drive pulley  320  in respective clockwise and counter-clockwise directions. 
     Accordingly, the two operating modes require that normal operation occur between a 12:00 o&#39;clock and 6:00 o&#39;clock position on pulley  324  which does not provide maximum stroke for a given amount of mechanical advantage as provided by the accompanying kinematic linkages (and in the first operating mode). Secondly, the clockwise and counter-clockwise reciprocating motion of the kinematic linkages in servo motor  262  is not efficient or optimal for high-speed operation. The associated moments of inertia are undesirable for relatively high operating speeds because the associated masses of the kinematic components suddenly change (or reverse) direction at high speed, which is undesirable and creates imbalance forces and increasing loading at component connections. 
     Accordingly, improvements are needed to provide a more efficient and high-speed article ejector for a high-speed thermoforming trim press. Furthermore, it is desirable to provide more optimal use of kinematic linkages and to reduce the negative effects of inertial operating forces to increase the operating speed and effectiveness of an article ejector. 
     SUMMARY OF THE INVENTION 
     An article ejector is provided having kinematic linkages that drive ejector paddle assemblies in an article ejector mode, as well as a die cleaning mode where the kinematic linkages are driven via rotary motion in a continuous clockwise direction, in both modes, without having to impart changes in direction for the rotary drive mechanisms, and while maintaining maximum mechanical advantage of the kinematic linkages. 
     According to one aspect, a trim press is provided having a first platen, a second platen, an article accumulator, and an article ejector. The first platen has at least one male die. The second platen has at least one female die. The article accumulator has a flywheel drive mechanism configured to rotate in a continuous forward direction with an offset crank arm configured to drive at least one ejector paddle to and fro. The at least one ejector paddle ejects articles from the female die into the cavity in a first mode of operation. 
     According to another aspect, an article ejecting device includes a platen, an articulating frame, an article ejector; and a frame moving mechanism. The articulating frame is carried for movement by the platen between an article stacking position and an article ejecting position. The article ejector mechanism is movably carried by the frame between a retracted position and an extended position. The frame moving mechanism is configured to move the frame and the article ejector mechanism between an article stacking position and an accumulator cavity clean-out position. 
     According to yet another aspect, a trim press article ejector is provided with a base, an articulating frame, an actuator, and an article ejector. The articulating frame is carried by the base. The actuator is coupled with the frame and is operative to move the frame between extended and retracted positions relative to the base. The article ejector is carried by the frame and has at least one paddle movable to and fro to eject articles from a trim press die. The extended position of the frame places the article ejector in an article stacking position. The retracted position of the frame places the article ejector in a clean-out position. 
     According to yet even another aspect, a method is provided for stacking and cleaning out thermoformed articles. The method includes: providing a trim press having a first platen with at least one male die and a second platen with at least one female die, the first and second platens movably supported to and fro therebetween, an article ejector supported on the first platen via an articulating frame, and an article accumulator having at least one cavity communicating with the female dies; positioning the articulating frame in a first position corresponding with the article accumulator configured in an article stacking position; stacking one or more articles by reciprocating the article ejector to and fro while the articulating frame is in the first position; positioning the articulating frame in the second position corresponding with the article accumulator configured in a clean out position; and cleaning out the at least one cavity of the article accumulator by reciprocating the article ejector to and fro while the articulating frame is in the second position. 
     One advantage is to reduce sudden changes in direction of kinematic components on an article ejector for a trim press which will impart undesirable inertial forces to the machine that can limit overall operating speed and performance. 
     Another advantage is to provide continuously rotating kinematic components that have a mass that is configured to store energy as a fly wheel such that rotation of the kinematic linkages does not oscillate between clockwise and counter-clockwise directions. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred embodiments of the invention are described below with reference to the following accompanying drawings. 
         FIG. 1  is a vertical side view of a thermoforming machine trim press having an article ejector embodying one aspect of the invention; 
         FIG. 2  is a simplified vertical front view of the thermoforming machine trim press and article ejector of  FIG. 1  taken from a right side of  FIG. 1 , omitting some components in a lower portion of the trim press to emphasize the article ejector assemblies; 
         FIG. 3  is an enlarged partial, vertical side view of the article ejector of  FIG. 1  further illustrating construction of the article ejector in partial vertical sectional view; 
         FIG. 4  is a perspective view of the upper platen and article ejector of  FIGS. 1–3 ; 
         FIG. 5  is a perspective view of the article ejector of  FIG. 4 , but with the upper platen removed; 
         FIG. 6  is a further enlarged perspective view taken within the encircled region  6  of  FIG. 5  and further illustrating the ejector bridge and ejector paddle assemblies of the article ejector; 
         FIG. 7  is a perspective view of a prior art article ejector configured for mounting on a top platen of a thermoforming machine similar to the thermoforming machine depicted in  FIGS. 1–2 ; 
         FIG. 8  is a left end view of the prior art article ejector of  FIG. 7 ; 
         FIG. 9  is a simplified side view of the article ejector of  FIGS. 1–6  and illustrating positioning of the article ejector prior to severing and ejecting the article into a stack of articles within an article accumulator provided below within the female die; 
         FIG. 10  is a simplified side view of the article ejector of  FIG. 9 , but illustrating the article ejector with the ejector paddles positioned to eject a newly severed article into a stack of articles within the article accumulator, corresponding with maximum displacement of the ejector paddles while in a normal operating mode; 
         FIG. 11  illustrates the article accumulator of  FIGS. 9–10  for a cleanout mode of operation wherein the article ejector frame has been downwardly articulated to further increase stroke of the ejector paddles to clean out scrap or damaged product or film material from within the female dies of the article accumulator. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     This disclosure of the invention is submitted in furtherance of the constitutional purposes of the U.S. Patent Laws “to promote the progress of science and useful arts” (Article 1, Section 8). 
     Reference will now be made to a preferred embodiment of Applicant&#39;s invention. An exemplary implementation is described below and depicted with reference to the drawings comprising an article ejector and method for ejecting articles and material from a die assembly in an article accumulator of a thermoforming trim press. 
     While the invention is described by way of the preferred embodiment, it is understood that the description is not intended to limit the invention to this embodiment, but is intended to cover alternatives, equivalents, and modifications which may be broader than this embodiment, such as are included within the scope of the appended claims. 
     Furthermore, in an effort to prevent obscuring the invention at hand, only details germane to implementing the present invention will be described in great detail. Presently understood peripheral details will be incorporated by reference, as needed, as being presently understood in the art. 
     A preferred embodiment of Applicants&#39; invention is shown implemented on a thermoforming machine trim press  10 , wherein the invention is generally designated with reference numeral  50  in  FIG. 1 . An article ejector  50  is mounted atop an upper platen  32  of trim press  10  for ejecting individual articles  68  from within an article cavity  45  from within a female die  44  of a lower platen  33 . Articles  68  are severed from a web  76  of thermoformable plastic material as the web is advanced by a web conveyor  72  via a conveyor chain drive system  74  that is identified in simplified form as a pair of co-acting drive rollers provided on opposite edges of web  76 . A treadle  61  (partially shown) also advances the web  76  into trim press  10 . 
     A control system  78  choreographs operation of trim press  10  along web conveyor  72  in order to move web  76  of thermoformed plastic material in which individual articles, or products,  68  have been previously formed using a thermoforming machine (not shown). In operation, web  76  is driven in intermittent motion under the control of control system  78  in order to intermittently feed individual rows of articles  68  for severing from web  76  using trim press  10 . In one case, there are five articles  68  within a single row of web  76 . 
     An article accumulator  47  is provided on trim press  10  in order to accumulate severed articles  68  into individual stacks  48 . Stacks  48  are intermittently deposited atop an article conveyor  46  for delivery to a packaging machine. Such stacks  48  of articles  68  are then loaded into individual packages or plastic bags. According to one implementation, conveyor  46  is intermittently activated to move stacks  48  of articles  68  for delivery to a bagging system (not shown) once desired stack sizes have been realized atop conveyor  46 . 
     As shown in  FIG. 1 , web conveyor  72  is illustrated in simplified form as a drive wheel assembly, even though it is actually a chain drive  74 , including servo motors that are controllably actuated via control system  78  to impart intermittent motion to web  76 . Accordingly, intermittent actuation of chain drive  74  via control system  78  is operative to intermittently deliver rows of articles  68  into trim press  10 . Such rows of articles  68  are then severed as control system  78  actuates a severing operation via trim press  10 . Subsequently, scrap web  66  is delivered from trim press  10  and ground into small pieces using a plastic comminuting device configured for grinding up scrap web  66 . 
     It is understood that article conveyor  72  is shown in simplified form. One exemplary detailed construction for article conveyor  72  is disclosed in U.S. Pat. No. 5,806,745, issued Sep. 15, 1998, entitled “Adjustable Conveyor for Delivering Thin Web Materials”, naming Jere F. Irwin as inventor, and which is incorporated by reference herein. 
     As shown in  FIGS. 1 and 2 , trim press  10  includes a frame  12  including frame members  14  that support a servo drive motor  18  and a gear box  16 . Motor  18  and gear box  16  drive a movable upper platen  32  via throw arms  20 ,  21  and  22 ,  23  which drive crank arm assemblies  24 ,  26  and  28 ,  30 , respectively, to raise and lower upper platen  32 . A pair of main die posts  38  and  40  guide upper platen  32  in up and down motion via associated bushings (not numbered), as well as via a tool die post  34 . Details of one exemplary thermoforming machine having such crank arm assembly for moving an upper platen and having counterbalance features are shown in U.S. Pat. No. 6,067,886, issued May 30, 2000, entitled “Machine Trim Press Having Counterbalance Features”, naming Jere F. Irwin as inventor, and which is incorporated by reference herein. 
     Each crank arm assembly  24 ,  26 ,  28  and  30  comprises a throw arm  20 - 23 , respectively, and a platen connecting rod  25 ,  27  and  29 ,  31 , respectively. For example, arm  20  and rod  25  cooperate to form a kinematic linkage that drives a dedicated corner of platen  32  for vertical, guided reciprocation. Additionally, main die posts  38  and  40  are rigidly carried in a stationary position by frame  12  to support platen  32  for movement in an axial, vertical direction. Article ejector  50  includes an articulating frame  52  that can be positioned between a raised and lowered position via a pair of pneumatic cylinders  54  and  56 . In a normal operating mode, articulating frame  52  is provided in a raised position for downwardly ejecting articles  64  that have been severed into cavity  45  of article accumulator  47  for storage and stacking therein. In a second operating mode, cylinders  54  and  56  are retracted so as to lower frame  52  to a downward position in order to increase stroke of an ejector bridge assembly  64  to increase stroke of a plurality of individual ejector paddle assemblies  144  to clean damaged parts and web material from dies  43 ,  44  and cavity  45 . 
     Control system  78  includes controller  80 . Controller  80  includes processing circuitry  82  and memory  84 . According to one construction, processing circuitry  82  is provided by a microcontroller. Alternatively, processing circuitry  82  is provided by a central processing unit (CPU). It is understood that memory  84  is operative to store software subroutines that are retrieved and implemented on processing circuitry  82  in order to impart motion control functionality by way of controller  80  to servo motors, motors, and components that operate trim press  10  including article conveyor  46 , article accumulator  47 , and article ejector  50 . Furthermore, control system  78  sends control signals to a pneumatic manifold (or supplies of compressed air)  86  to control delivery of air  88  and air  90  to extend and retract pneumatic cylinders  54  and  56  in a controlled manner to shift between two operating states for article ejector  50 . 
     In operation, individual male dies  43  are supported on a die plate  42  for co-action with female dies  44  above lower platen  33 . Such co-action severs articles  68  from web  76 . 
     Control system  78  further controls operation of servo motor  62  of article ejector  50  in order to control the movement of crank arm assemblies  58  and  60  which direct movement of ejector paddle assemblies  144  downwardly to push down severed articles  68  into cavity  45  for collection. Likewise, control system  78  further imparts control to a servo drive  92  for article conveyor  46  to advance articles (as well as ejected scrap material) from beneath conveyor  10  to another station. In one case, scrap material is ejected in one direction whereas stacks  48  of accumulated articles  68  are ejected in an opposite direction for collection and bagging. Furthermore, control system  78  can regulate raising and lowering of article conveyor  46  via control signals. 
       FIG. 3  illustrates the positioning of article ejector  50  in a fully upwardly retracted position when upper platen  32  is lowered into engagement with lower platen  33  during a severing operation of a web (not shown) when male die  43  co-acts with female die  44  to sever an article, but prior to extending ejector paddle assemblies  144  in a downward direction to eject articles into corresponding cavities  45  within an article accumulator  47 . As shown in  FIG. 3 , ejector paddle assembly  144  is in a fully raised position and article ejector  50  has frame  52  in a fully raised position in a first operating state. Accordingly, cylinders  54  and  56  are shown in an extended position so as to raise frame  52  which further raises crank arm  60  and ejector paddle assemblies  144  to a fully elevated position. Upper platen  32  is shown supported for vertical reciprocation via die posts  38  and  40  such that upper platen  32  can be raised after severing articles between dies  43  and  44 . 
     A plurality of male dies  43  are provided spaced apart along a die plate  42  that is secured with fasteners to a bottom surface of upper platen  32 . Each ejector paddle assembly  144  is configured to move for vertical axial reciprocation along a bearing surface  65  provided in association with upper platen  32  and die plate  42 . Accordingly, the array of ejector paddle assemblies  144  provides an ejector bridge assembly  64  that is supported by upper platen  32 . 
     Servo motor  62  is actuated to rotate drive pulley  120  to rotate driven pulley  124  via drive belt  130  in one circular, forward direction. Accordingly, crank arm assembly  60  is mounted at an off-center position on pulley (or wheel)  124  such that crank arm  96  is driven as pulley  124  rotates completely circumferentially in a clockwise direction (as shown in  FIG. 3 ). Crank arms  58  and  60  are each mounted at opposite ends with bearing fastener assemblies  96  and  98 . For example, crank arm  58  is mounted at one end to pulley  124  as well as at another end to a top portion of an ejector bridge  110 . 
     As shown in the fully raised configuration depicted in  FIG. 3 , each ejector paddle assembly  144  is made substantially of aluminum components, including a cylindrical distal end paddle  172  upon which a resilient foam pad  174  is affixed for engaging and contacting severed articles before ejecting articles into cavity  145 . 
     As shown in  FIG. 3 , cylinder  56  is affixed at one actuating end via a bearing mount  160  and at a distal, opposite end via a mounting block  134  to a top portion of upper platen  32 . 
     As shown in  FIG. 4 , ejector bridge  110  is supported for vertical movement up and down within upper platen  32  by way of alignment posts  112  and  114  that are mounted at either end to inner surfaces of upper platen  32 . A bronze bushing assembly  116  and  118  is provided at opposite ends of ejector bridge  110  to provide for vertical axial aligned movement of ejector bridge  110  along posts  112  and  114 . Spaced along ejector bridge  110  are a plurality of ejector paddle assemblies  144 , each configured to align with a respective female die and a lower platen for ejecting severed articles into respective cavities provided therebelow in an article accumulator (not shown). 
     As shown in  FIG. 4 , bearing mounting bores  138  and  140  are provided for receiving bearings that ride on main die posts  38  and  40 , respectively. 
     As shown in  FIG. 4 , articulating frame  52  on article ejector  50  includes a pair of side plates  53  and  55  that are rigidly affixed together by way of a pair of cross-posts  57  and  59 . A drive shaft  108  is supported for rotation by way of two bearing assemblies between side plates  53  and  55 , and is driven by driven pulley  124  via belt  130  and drive pulley  120 . Accordingly, a wheel  122  is driven for rotation at an opposite end of shaft  108  from pulley  124 . Wheel  122  drives crank arm  58 , whereas pulley  124  drives crank arm  60 . Hence, ejector bridge  110  is driven vertically upwardly and downwardly for vertical reciprocation as guided by way of posts  112  and  114  at either end. 
     More particularly as shown in  FIG. 4 , a lower end of each crank arm  58  and  60  is attached by way of a bearing assembly to a respective mounting bracket  148  and  150  that is provided along ejector bridge  110 . Furthermore, ejector paddle assemblies  144  (numbering five, in this case) are mounted in spaced-apart relation along ejector bridge  110 . 
     As shown in  FIG. 4 , articulating ejector  50  is illustrated with frame  52  rotated up to a raised position by way of extending pneumatic cylinders  54  and  56 . Distal ends of cylinders  54  and  56  are pivotally affixed to mounting blocks  132  and  134  atop upper platen  32 . 
     In the raised configuration of frame  52 , crank arms  58  and  60  are able to move ejector bridge  110  up and down a distance of stroke that is defined by the upper and lower positions of crank arm  60  provided by the offset mounting portion of crank arm  60  off-center on pulley  124  and wheel  122 . By moving the attachment of the crank arm connection points for crank arms  59  and  60  between 12:00 o&#39;clock and 6:00 o&#39;clock positions, a full depth of stroke for ejector bridge  112  is defined under a first mode of operation where articles are driven downwardly to eject the articles into an accumulation device for stacking or accumulating under normal article stacking operations. 
     In another mode of operation (a cleanout mode), pneumatic cylinders  54  and  56  are retracted so as to lower frame  52  via pivoting at pivot bearing assemblies  145  and  146 . Accordingly, the upper attachment point for crank arms  58  and  60  is substantially lowered, which enables deeper draw of ejector paddle assemblies  144  (see  FIG. 3 ) within the cavity for each article. Such second mode of operation is particularly useful when a piece of thermoformable web material or damaged article has become misaligned or trapped between the dies or within the article cavity. When this happens, an operator retracts cylinders  54  and  56  and drives crank arms  58  and  60  to the lowered position to eject the damaged or unwanted material from the cavities and the die in the article accumulator. Afterward, an article conveyor provided therebelow can be moved in a direction opposite the direction that is normally used to remove stacked articles (for bagging at a bagging station) for processing of the damaged or waste material into a comminuting device or storage bin. 
     As shown in  FIG. 4 , servo motor  62  drives pulley  120  so as to further drive crank arms  58  and  60  in a clockwise, or forward, direction. Preferably, the majority of the support components making up article ejector  50  are made from as light a material as possible, such as from aluminum. Others are made of steel (such as fasteners). However, the rotary motion of pulley  124 , wheel  122 , and shaft  108  continues to rotate in a continuous, same rotational direction. Accordingly, their motion acts as a fly wheel that maintains a single rotating direction. In contrast, the prior art system of  FIGS. 7–8  rotates alternative assemblies back and forth which can significantly create problems because of the change in direction of the moving masses. This will not allow the prior art article ejector to operate in as smooth a manner or as fast an operating speed because of the changing in direction of the mass of the associated rotating components. 
       FIG. 5  illustrates in greater detail the article ejector  50  as removed from the upper platen (of  FIG. 4 ). Accordingly, the mounting of ejector paddle assemblies  144  along ejector bridge  110  can be more readily seen. Preferably, crank arms  58  and  60 , ejector bridge  110 , and the structural components of ejector paddle assembly  144  are all formed from lightweight material, such as aluminum to reduce moving moments of inertia. 
     As shown in  FIG. 5 , ejector paddle assembly  144  comprises a perforated, cylindrical paddle  172  carried at the bottom end of a mounting rod  170  that is affixed at an upper end to mate with a threaded fastener  177 , wherein upper and lower brackets  168  and  169  clamp on the top and bottom faces of ejector bridge  110  as threaded fastener  177  is received into a complementary, corresponding threaded bore at the top end of rod  170 . Accordingly, ejector paddle assembly  144  is rigidly affixed to depend below ejector bridge  110 . Furthermore, a pair of threaded fasteners  177  further secure together brackets  168  and  169  to bridge  110 . 
     At a bottom end of paddle  172 , a relatively lightweight foam pad, or plug, is provided for engaging with articles as the articles are being driven downwardly by paddle  172  and pad  174  during an article ejection process, or during a cleaning process when cleaning out jammed material or damaged articles from within a cavity within the die or within an article accumulator therebelow. 
     As shown in  FIG. 5 , upper brackets  152  and  154  are mounted along a top edge of the upper die (not shown). Similarly, bottom brackets  158  and  160  are mounted to an inner surface of the upper die in order to vertically affix die posts  112  and  114 . 
     As further shown in  FIG. 5 , a pair of ball bearings  160  and  162  are provided at the actuating end of frame  52 , recessed within side plates  53  and  55 . Furthermore, additional bearings, such as bearing  166 , are provided at the points where frame  52  pivots atop the upper platen (not shown). Also as shown in  FIG. 5 , frame  52  forms a rigid support structure by way of side plates  53  and  55  being rigidly affixed together by way of cross-posts  57  and  59 . Accordingly, drive shaft  108  is supported at each end by a bearing (not shown) to enable continuous rotary motion of pulley  124  and wheel  122  in a single clockwise direction. Alternatively, the wheel  122  and pulley  124  can be driven only in a counter-clockwise direction, where movement starts and stops, but direction of rotation does not change as article ejector  50  is actuated down and up, intermittently, during article ejection stages. 
     As shown in  FIG. 6 , crank arm  60  is connected via a pivotal bearing assembly to angle bracket  150 . Angle bracket  150  is affixed to a top edge of ejector bridge  110  using a plate  151  and a threaded bolt  153 . Engagement of threaded bolt  153  draws together a bracket  150  and plate  151  so as to rigidly affix bracket  150  atop ejector bridge  110 . 
       FIG. 9  illustrates the position of article ejector  50  when used under a first operating condition for ejecting articles  68  that have been severed between die  43  and female die  44  for stacking such severed articles on top of stack  48  within cavity  45  of an article accumulator  47 . As shown in  FIG. 9 , frame  52  is elevated via pneumatic cylinders  54  and  56  to the shown operating position. 
       FIG. 10  illustrates rotation of pulley  124  from a 12:00 o&#39;clock position shown in  FIG. 9  to a 6:00 o&#39;clock position shown in  FIG. 10  which downwardly drives crank arm  60  and moves from a highest, most elevated position of ejector paddle assembly  144  in  FIG. 9 , to a lowest-most position in  FIG. 10 . By decrementing the timing of when ejector paddle assembly  144  reaches its lower-most position (corresponding with the position shown in  FIG. 11 ), relative to when platen  32  starts to move up, the final resting position of an article  68  can be modified. 
     For example, if 50 plates are being stacked within accumulator  47 , the time at which ejector paddle assembly  144  places a paddle at a bottom-most position can be varied to a point in time when upper platen  32  has been raised a quarter inch. Accordingly, such a position may correspond with a relatively large stack of articles, such as a count of 50 articles being stacked within cavity  45 . In contrast, if only 25 articles are being stacked, the bottom-most position of the paddle on ejector paddle assembly  144  can be timed to occur when upper platen  32  is at a lowest-most position of travel along the trim press. 
     Further optionally, as each successive article  68  is added onto a stack  48 , it is possible to decrement the time at which the paddle on ejector paddle assembly  144  reaches a bottom-most stroke position later in time from the point at which upper platen  32  reaches the lowest-most position. Hence, subsequent articles  68  are downwardly ejected onto stack  48  later in time such that later articles are stacked with the paddle as the upper platen  32  has begun to start moving upwardly from its lowest-most position. 
       FIG. 11  illustrates an alternative operating condition for article ejector  50  wherein pneumatic cylinders  54  and  56  are retracted, or shortened, so as to downwardly pivot frame  52  which lowers the center position of pulley  124  to further lower the crank position of crank arm  60 . The net effect is that ejector paddle assembly  144  is further lowered within cavity  45 . Accordingly, pulley  124  can be rotated to downwardly drive crank arm  60  in combination with shortening of pneumatic cylinders  54  and  56  to more deeply drive the paddle of ejector paddle assembly  144  downwardly a maximal amount within cavity  45  so as to clean out web material  76  that is inadvertently lodged within cavity  45  during a cleanout operation. Such a cleanout operation is only done when an operator discovers that web  76  has become damaged or caught between die members  43  and  44 , or when damaged articles  68  have been jammed within cavity  45 . 
     As previously stated, by adjusting the timing of servo  62  to adjust the timing when ejector paddle assemblies  144  reach a bottom-most position relative to the time when the upper platen is at a lowest-most position, the maximum relative position of a bottom end of the respective paddle relative to the female die and article cavity varies. By retarding the timing such that the paddle reaches a maximum bottomed-out condition as the upper platen starts to move away, the relative position of an article is not pushed as far down as if the bottom-most position of the paddle corresponds with the bottom-most position of the upper platen. By incrementally increasing the retardation time when the paddle reaches a bottom-most position, but when the upper platen is concurrently starting to move up, the depth to which an article is downwardly driven can be reduced incrementally. Accordingly, a control scheme can be implemented wherein increasing numbers of articles in a stack dictate that the retardation time therebetween is reduced or eliminated. For the case where a relatively small stack is being accumulated, a greater retardation time may be desirable. 
     A trim press having an article ejector is provided with a kinematic linkage having a crank driven by a rotary mechanism that rotates continuously in one circular direction to drive the crank arm and at least one corresponding ejector paddle in reciprocating motion to eject articles from between a pair of mating male and female dies after severing. 
     In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents.