Abstract:
A safety device for automated processing equipment which is disposed in combination with a linear actuator to prevent operator injury. The safety device includes a base plate and a spherical element engaging the base plate to effect relative displacement of structural elements having at least one spring element projecting downwardly from the base plate, the base plate defining an aperture therein having a peripheral edge, and the at least one of the spring element including a ramped surface defining a lead angle relative to a horizontal plane, and
       a spherical element coupled to the end of the actuation shaft and engaging the peripheral edge of the aperture in a coupled operating mode, and disengaging the peripheral edge of the aperture when transitioning from the coupled operating mode to a safe operating mode.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a safety device for a linear actuation system and, more particularly, to a safety device with prevents operator injury in the event that an appendage or article of clothing, of an operator is inadvertently captured between structural elements which move relative to each other. 
     BACKGROUND OF THE INVENTION 
     Various apparatus are employed for arranging sheet material in a package suitable for use or sale in commerce. One such apparatus, useful for describing the teachings of the present invention, is a mailpiece inserter system employed in the fabrication of high volume mail communications, e.g., mass mailings. Such mailpiece inserter systems are typically used by organizations such as banks, insurance companies, and utility companies for producing a large volume of specific mail communications where the contents of each mailpiece are directed to a particular addressee. Also, other organizations, such as direct mailers, use mail inserters for producing mass mailings where the contents of each mail piece are substantially identical with respect to each addressee. Examples of inserter systems are the 8 series, 9 series, and APS™ inserter systems available from Pitney Bowes Inc. located in Stamford, Conn., USA. 
     In many respects, a typical inserter system resembles a manufacturing assembly line. Sheets and other raw materials (i.e., a web of paper stock, enclosures, and envelopes) enter the inserter system as inputs. Various modules or workstations in the inserter system work cooperatively to process the sheets until a finished mail piece is produced. For example, in a mailpiece inserter, an envelope is conveyed downstream utilizing a transport mechanism, such as rollers or a belt, to each of the modules. Such modules include, inter alia, (i) a singulating module for separating a stack of envelopes such that the envelopes are conveyed, one at a time, along the transport path, (ii) a folding module for folding mailpiece content material for subsequent insertion into the envelope, (iii) a chassis module where sheet material and/or inserts, i.e., the content material, are combined to form a collation, (iv) an inserter module which opens an envelope for receipt of the content material, (v) a moistening/sealing module for wetting the flap sealant to close the envelope, (vi) a weighing module for determining the weight of the mailpiece for postage, and (vii) a metering module for printing the postage indicia based upon the weight and/or size of the envelope, i.e., applying evidence of postage on the mailpiece. While these are some of the more commonly used modules for mailpiece creation, it will be appreciated that the particular arrangement and/or need for specialty modules, are dependent upon the needs of the user/customer. 
     The chassis module includes a transport deck having a plurality of pockets and plurality of overhead feed input stations for dispensing inserts onto each pocket of the transport deck. In the context used herein, “inserts” refers to any sheet material, regardless of size and/or whether folded or unfolded, containing information for inclusion into a mailpiece as content material. In many instances, the inserts are added, by the overhead feed input stations, to sheet material previously supplied, at an upstream input module, to the pockets of the chassis module. Chassis modules may have as many as sixteen (16) to twenty-four (24) feed input stations for supplying each of the underlying pockets with original and/or additional content material. Periodically, these feed input stations must be re-loaded to maintain a steady supply of each type of insert. As a result, there is a continuous need for a re-supply of the various inserts to produce the content material of each mailpiece. 
     While such inserts are commonly pre-printed and supplied as fixed inputs, i.e., incapable of changing the information provided or configuration of the insert (e.g., folded or unfolded), frequently there is a need to change the information conveyed or change the configuration of the insert. For example, it may be necessary to change the price of a product/service offered, or vary the size of an insert for receipt within a different type of envelope, e.g., envelopes for accepting flats, letter-sized, tri-fold content material. Currently, there are no insert print modules capable of producing and/or arranging a variable supply of content material inserts. Consequently, such changes require that a mailpiece fabricator await the supply of newly printed/configured inserts to produce mailpieces for a particular mail run/job. 
     Additionally, to the extent that mailpiece inserts include relative moving components/structural elements, hazards may exist for operators when operating the various mechanical components. Such inserters may include relatively moving components capable of capturing/injuring an operator should an appendage, or article of clothing, of an operator be inadvertently captured between the structural elements. 
     A need, therefore, exists for a safety device which prevents injury to an operator should structural elements, which move relative to each other, have the capacity to inflict injury. 
     SUMMARY OF THE INVENTION 
     A safety device for automated processing equipment which is disposed in combination with a linear actuator to prevent operator injury. The safety device includes a base plate and a spherical element engaging the base plate to effect relative displacement of structural elements having at least one spring element projecting downwardly from the base plate, the base plate defining an aperture therein having a peripheral edge, and the at least one of the spring element including a ramped surface defining a lead angle relative to a horizontal plane, and a spherical element coupled to the end of the actuation shaft and engaging the peripheral edge of the aperture in a coupled operating mode, and disengaging the peripheral edge of the aperture when transitioning from the coupled operating mode to a safe operating mode. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further details of the present invention are provided in the accompanying drawings, detailed description, and claims. 
         FIG. 1  is a schematic top view of an insert fabricating module for organizing, arranging and conveying the printed sheet material and a schematic top view of a chassis module of a mailpiece inserter for receipt of the printed sheet material. 
         FIG. 2  is an isolated perspective view of an output module having at least two transport decks disposed in combination with a rotating support structure and adapted to receive printed sheet material from a transfer module of the insert fabricating module depending upon a selected operating mode thereof. 
         FIG. 3  is a side profile view of the output module wherein one of the transport decks of the output module includes a plurality of separators defining a pocket for receipt of one or more stacks of sheet material from a transfer module, and the other of the transport decks is adapted to receive a shingled stack of printed sheet material from the transfer module. 
         FIG. 4  is a front view of the output module wherein an actuator rotates the support structure about a rotational axis to vary which of the transport decks receives the printed sheet material based upon the selected operating mode. 
         FIG. 5  is a side profile view of the output module wherein support structure is extended and retracted (depicted in solid and dashed lines, respectively) such that the appropriate transport deck may rotated into a position corresponding to the selected operating mode. 
         FIG. 6  is an isolated perspective view of the output module including a safety device for extending and retracting the support structure and wherein the safety device prevents operator injury due to the relative displacement of structural elements, e.g., the extended and retracted positions of the support structure. 
         FIG. 7   a  depicts a view taken substantially along line  7   a - 7   a  of  FIG. 6  depicting the safety device, in accordance with the present invention, in a coupled operating mode wherein one of the structural elements, e.g., the support structure, is extended relative to another of the structural elements, e.g., the transfer module. 
         FIG. 7   b  depicts a view taken substantially along line  7   b - 7   b  of  FIG. 6  depicting the safety device in a coupled operating mode wherein one of the structural elements, e.g., the support structure, is retracted relative to another of the structural elements, e.g., the transfer module. 
         FIG. 8   a  depicts a view taken substantially along line  8   a - 8   a  of  FIG. 6  depicting the safety device in a coupled operating mode (shown in dashed lines) and in a safe operating mode (shown in solid lines). 
         FIG. 8   b  depicts a view taken substantially along line  8   b - 8   b  of  FIG. 8   a  depicting a cross-sectional view of the safety device including a base plate having first and second spring elements which deflect in response to a vertical force component imposed by a spherical element thereby engaging and disengaging the base plate, i.e., the coupled and safe operating modes, respectively. 
         FIG. 8   c  depicts an enlarged view of the safety device shown in  FIG. 8   b  depicting the engagement/disengagement of the spherical element from the base plate based upon the vertical force component imposed by the spherical element. 
     
    
    
     DETAILED DESCRIPTION 
     A system is described for fabricating sheet material/inserts for a mailpiece inserter. Additionally, a safety device is described for preventing injury to an operator in the event that an appendage, or article of clothing, of the operator is captured between moving elements of the inserter. While the safety device is described in the context of an insert fabricating module dedicated to producing printed inserts for a chassis module of a mailpiece inserter, it will be appreciated that the safety device may be employed in any system having relatively moving structural elements/components. The safety device of the present invention is, therefore, merely illustrative of an embodiment of the present invention, and should not be construed as limiting the meaning and scope of the appended claims. 
     Insert Fabrication Module 
     In  FIG. 1 , an insert fabricating module  10  is depicted for producing a supply of sheet material inserts for use in a mailpiece inserter  12 , e.g., overhead feed input stations (not shown) of the chassis module  14  thereof. The insert fabricating module  10  includes an input module comprising one of a web supply module  16  and a sheet feed module  18 . The web supply module  16  may include a rolled web  20  of sheet material which is printed in accordance with a mail run data file  22  associated with a particular mailpiece fabrication job. The rolled web  20  may be processed by a cutting station  24  which produces individual sheets of insert material  30  (along a first feed path FP 1 ) associated with the mailpiece fabrication job. Alternatively, or additionally, the sheet feed module  18  may be integrated with the insert fabricating module  10  to supply a plurality of pre-cut inserts  32  (along a second feed path FP 2 ) which are similarly processed in accordance with the mail run data file  22  associated with the mailpiece fabrication job. Accordingly, the insert material  30 ,  32  employed in the insert fabricating module  10  of the present invention may be provided by the web supply module  16  or the sheet feed module  18 . 
     To track, organize and arrange insert material  30 ,  32  based upon the mailpiece fabrication job, scanners  34 ,  36  may be disposed at the output end of each of the web supply and a sheet feed modules  16 ,  18 . More specifically, the scanners  34 ,  36  are adapted to read scan codes or other symbology disposed on one or more of the inserts  30 ,  32 , typically within the margins of the printed inserts  30 ,  32 , such that a processor  40 , electrically coupled to, and in electronic communication with, the insert fabricating module  10 , may determine the number of inserts  30 ,  32  associated with a particular mailpiece fabrication job or individual mailpiece. The processor  40  is also in communication with, and controls, the other modules of the insert fabricating module  10 , i.e., an accumulator module  44 , a folder module  46 , a transfer module  48 , and an output module  50 . 
     Depending upon the origin of each of the inserts  30 ,  32 , i.e., inserts  30  from the web supply module  16 , or inserts  32  from the sheet feed module  18 , inserts  30  from the web supply module  16  may be conveyed through a right angle turn module  42  to re-direct the insert material  30 , i.e., ninety (90) degrees, to the accumulator module  44 . The same right-angle turn module  42  may convey sheet material inserts  32  from the sheet feed module  18 , as a straight line input, to the accumulator module  44 . The function of the accumulator module  44  is conventional and will not be described in greater detail herein. Suffice it to say that the accumulator module  44  may be employed to combine the insert material  30 ,  32  into packets of content material for use in the fabrication of an individual mailpiece, i.e., a collation of sheets, or simply as a buffer to accumulate a predetermined number of sheets. 
     Depending upon the end-use of the sheet material inserts  30 ,  32 , a folder module  46  may be interposed between the accumulator module  44  and the transfer module  48  to fold the insert material  30 ,  32 , or transfer/pass the insert material  30 ,  32  without being folded. Therein, the inserts  30 ,  32 , whether stacked into a collation or processed as an individual sheet from the accumulator module  44 , may be bi-folded, tri-folded or gate-folded, such that the inserts  30 ,  32  may be placed into a particular size envelope, e.g., a type ten (10) envelope. Alternatively, the inserts  30 ,  32  may be transferred directly, without being folded for inclusion into another type of envelope, e.g., a flats-type envelope. 
     In  FIGS. 1 and 2 , the transfer module  48  conveys the sheet material inserts  30 ,  32  from the folder module  46  to the output module  50  of the insert fabrication module  10 . Furthermore, the transfer module  48  is controlled by the processor  40  to dispense a pre-determined number of inserts  30 ,  32  onto at least one of two transport or conveyor decks  52   a ,  52   b  of the output module  50 . Once again, the number of sheet material inserts  30 ,  32  is a function of that prescribed by the mail run data file of the mailpiece fabrication job. For example, if a mailpiece fabrication job requires that two-thousand (2,000) inserts of a total of five thousand (5,000) inserts be folded, then the folder and transfer modules  46 ,  48  may be commanded, by the processor  40 , to dispense four (4) stacks of five-hundred (500) folded sheet material inserts  30 ,  32  onto a transport deck  52 . 
     The transfer module  48  receives the sheet material inserts  30 ,  32 , from the folding module  46  and conveys the sheet material  30 ,  32  to the output module  50  along a feed path FP. The transfer and output modules  48 ,  50  are operative to arrange, stack, and convey the sheet material inserts  30 ,  32  in a manner consistent/commensurate with the inserts employed in connection with the mailpiece fabrication job. 
     In the described embodiment, and referring to  FIGS. 2 ,  3  and  4 , the output module  50  includes a support structure  54  which rotates about an axis  54 A and at least two transport decks  52   a ,  52   b  disposed in combination with the support structure  54 . The processor  40  receives input from the mail run data file  22  to determine which of the transport decks  52   a ,  52   b  is best suited to receive the sheet material inserts  30 ,  32 , i.e. based upon the size and/or configuration thereof to be used in the mailpiece inserter  12 . While the transport decks  52   a ,  52   b  may be adapted to receive any of a variety of stacked sheet material inserts  30 ,  32 , in the described embodiment, one of the transport decks  52   a ,  52   b  includes a plurality of separators  56  for receiving stacks of sheet material inserts  30 ,  32  while another includes a flat conveyor belt  58  for receiving a shingled stack of sheet material inserts  30 ,  32 . With respect to the transport deck  52   a , the separators  56  define pockets which function to separate stacks of printed sheet material inserts  30 ,  32 . Furthermore, the separators  56  register an edge of each stack while the sheet material  30 ,  32  is deposited between the separators  56 . 
     More specifically, the support structure  54  of the output module  50  includes an actuator  60  for rotating the support structure  54  about its rotational axis  54 A. As mentioned previously, the processor  40  issues command signals to the output module  50  to rotate the support structure  54  such that the appropriate one of the transport decks  52   a ,  52   b  is aligned with, and receives, the printed sheet material inserts  30 ,  32  from the transfer module  48 . In the described embodiment, a motor M, responsive to input from the processor  40 , drives a rotating shaft  62  having a first gear  64  connecting to and rotating with the shaft  62 . A belt or chain  66  wraps around and engages the first gear  64  to drive a second gear  68  which, in turn, drives a shaft  70 . The shaft  70  is coupled to, and drives, the support structure  54  of the output module  50 , about the axis  54 A. The processor  40 , therefore, drives the rotation, and position of, the output module  50 , based upon the selected operating mode of the insert fabrication module  10 , i.e., whether the insert fabrication module  10  is to receive and arrange the sheet material inserts  30 ,  32  as stacks of content material, or as a continuous stack of shingled sheet material  30 ,  32 . 
     To rotate the support structure  54 , it may be necessary to extend the transport decks  52   a ,  52   b  beyond the transfer module  48  such that output module  50  clears any structure/elements which may interfere with rotation of the support structure  54  associated with the transfer module  48 . Consequently, the output module  50  may be is adapted to extend/retract relative to the transfer module  48  to facilitate integration of the transfer and output modules  48 ,  50 . Accordingly, in the described embodiment, and referring to  FIGS. 5 ,  6 ,  7   a  and  7   b , the support structure  54  is mounted within guide rails/tracks  72  of a stationary structure  74  to extend and retract the support structure  54  of the output module  50  relative to the transfer module  48 . In the described embodiment, the tracks  72  are stationary and the support structure  54  is mounted, and guided within, the tracks  72  by a plurality of rolling elements  76 . A linear actuator  90 , mounted at one end of the stationary structure  74 , effects relative displacement between the structural elements, i.e., between the stationary structure  74  of the insert fabrication module  10  and the support structure  54  of the output module  50 . The support structure  54  is shown in an extended position to facilitate rotation of the output module  50 , i.e., the support structure  54  and transport decks  52   a ,  52   b , about the rotational axis  54 A. 
     While the insert fabrication module  10  of the present invention has been described as including a plurality of modules upstream of the output module  50  to process the sheet material/inserts  30 ,  32 , it will be appreciated that certain of the modules may be eliminated to reduce cost or minimize the size envelope of the fabrication module  10 . For example, the right angle turn module  42  may be eliminated should the insert fabrication module  10  receive an in-line, straight, input from either the web supply module  16  or the sheet feeder module  18 . Additionally, the accumulator module  44  may be eliminated if the transfer module  46  is adapted to receive the input directly from one of the input modules, i.e., the web supply or sheet feed modules  16 ,  18 , That is, the accumulator module  44  may be eliminated if the transfer module is adapted to handle the throughput or output of one of the input modules  16 ,  18  directly, without the need to accumulate or buffer the sheet material/inserts at an upstream station. 
     Safety Device for Automated Fabrication Equipment 
     Inasmuch as the insert fabrication system  10  of the present invention requires that a linear actuation device  90  be employed to extend/retract the support structure  54 , a safety device  100 , shown in  FIGS. 7   a  through  8   c , is provided to ensure operator safety when operating the insert fabrication module  10 . In the described embodiment, the linear actuation device  90  includes an actuation cylinder  92  and an actuation shaft  94  disposed in combination with the cylinder  92  which moves relative thereto along a line of motion, i.e., the longitudinal axis  96  of the shaft  94 . The safety device  100  employed in the insert fabrication system  10  may be used in any linear actuation device which employs moving parts, i.e., those which are capable of inflicting injury to an operator by the relative displacement of structural elements (e.g., trapping a finger/limb between moving elements). The safety device  100  employs a spring-biased base plate  102  and a spherical element  104  disposed in combination with the spring-biased base plate  102  which engages and disengages based upon a threshold level of applied force. Hence, the safety device  100  operates in a coupled operating mode and transitions to a safe operating mode, i.e., wherein the spherical element  104  disengages the base plate  102 . 
     In the described embodiment, the spherical element  104  is disposed in combination with the end of the shaft  94  and is mounted by a bearing  105  which permits relative rotation about the longitudinal axis  96  of the shaft  94 . As a result, the spherical element  104  is capable of rotation in a plane orthogonal to the longitudinal axis  96  of the shaft  94 . Furthermore, in the described embodiment, the spherical element  104  defines a diameter greater than about one (1) inches. 
     The base plate  102 , best seen in  FIG. 8   c , includes at least one spring element  106  projecting downwardly from the base plate  102  and includes an aperture  110  therein having a peripheral edge  114 . While the spring element  106  may include a single Belleville-type spring element, i.e., one or more spring elements disposed about a central circular-shaped structure, the base plate  102  of the present invention includes first and second spring elements  106   a ,  106   b , disposed forward and aft relative to the longitudinal axis  96  of the spherical element  104 . The first and second spring elements  106   a ,  106   b  include ramped surfaces  108  which define an angle within a range of between about ten (10) degrees and about forty (40) degrees relative to a horizontal plane HP. Preferably, the ramped surfaces  108  (see  FIG. 8   c ) define an angle within a range of between about fifteen (15) degrees and about thirty (30) degrees relative to the horizontal plane. 
     In operation, the safety device  100 , i.e., the spherical element  104 , imposes a threshold horizontal force component F 1  to the base plate  102  to effect relative displacement between the structural elements, i.e., between the stationary structure  74  of the insert fabrication module  10  and the support structure  54  of the output module  50 . Consequently, the linear actuation device  100  displaces the elements to extend/retract the support structure  54  of the output module  50 , i.e., to facilitate rotation and repositioning of the transport decks  52   a ,  52   b . Should an object or operator appendage be inadvertently disposed between the moving elements, spring elements  106   a ,  106   b  deflect downwardly, due to a vertical force component F 2  imposed by the spherical element  104  and produced by the horizontal force component F 1 , in the described embodiment, the threshold horizontal force F 1  component is less than about twenty-five (25) pounds, and, more preferably, is less than about seventeen (17) pounds. 
     It is to be understood that the present invention is not to be considered as limited to the specific embodiments described above and shown in the accompanying drawings. The illustrations merely show the best mode presently contemplated for carrying out the invention, and which is susceptible to such changes as may be obvious to one skilled in the art. The invention is intended to cover all such variations, modifications and equivalents thereof as may be deemed to be within the scope of the claims appended hereto.