Abstract:
An automated dispenser for straws is provided with a housing, a hopper, and a guide tray. The housing has a dispensing slot in an anterior outer wall. The hopper has an upper section with transverse walls and longitudinal walls which converge to define a stacking slot and a substantially horizontal support to support straws beneath the stacking slot. An anterior inner wall, longitudinally extending channel, and posterior wall span the longitudinal walls. The anterior inner wall has an ejection opening and the posterior wall has an access opening each of which adjoin the longitudinally extending channel. A support member and pressing foot within the stacking slot can translate longitudinally and pass through both the ejection opening and the access opening. A guide tray, disposed below the ejection opening, has a location zone, a posterior wall, and an anterior wall. The guide tray urges straws into the dispensing slot projecting upwardly.

Description:
[0001]    This application claims benefit priority of U.S. Provisional Application 61/987,756 filed May 2, 2014, entitled Sanitary Straw Dispenser naming Daniel Stone as inventor, incorporated herein by reference. 
     
    
       [0002]    Straws are omnipresent in the quick service restaurant industry being used for the wide variety of soft drinks that account for a large portion of the quick service restaurant owners&#39; margins. Yet even though they inherently come into contact with the customers drink and the customer&#39;s mouth, a truly sanitary and practical method of dispensing straws—often referred to as “soda straws”—has been lacking. This invention relates to an automated straw dispenser that, in preferred embodiments, effectively restricts customers from touching any surface that touches each straw as it is being dispensed. Furthermore, the dispenser presents straws one at a time to the customer in a manner which makes it intuitive to the customer that the straw is being dispensed and how to easily remove it for use by presenting it in an angled upwardly configuration that customers intuitively recognize as only requiring grasping and withdrawal of the straw. In preferred embodiments, a timing circuit provides a delay between removal of one straw and its replacement with another to discourage unnecessary use. 
         [0003]    Hitherto, in many cases, soda straws have been dispensed in a sanitary package which does prevent any other customer from touching the straw. Typically, these straws are referred to as “wrapped straws” even though they are more sealed in a sanitary package than wrapped. Wrapping of straws can add up to ten percent or more to the cost paid by the restaurant operator, adding to his costs and cutting significantly into his typically razor-thin margins. Moreover, they also make it easy for customers to take more than one straw, perhaps stockpiling for later use, while providing juveniles with the apparently almost irresistible opportunity to launch the wrappers as missiles against their companions, again leading to not only an incentive to take more straws than are actually needed but also requiring additional labor to police wrappers scattered over the restaurant. Thus, even though supplying of wrapped straws addresses a portion of the sanitation issue, the added cost-in-use strongly discourages their use. 
         [0004]    Yingst et al., U.S. Pat. No. 3,519,166 relates to an automated straw dispenser which provides straws projecting outwardly in horizontal disposition from the dispenser. Because Yingst employs a push through channel in which each straw is forced through a dispensing tube by another straw, this dispenser is susceptible to jamming and would be difficult to adapt to dispense upwardly angled straws in a limited volume as push-through dispensing conflicts with gravity feed from a horizontal hopper if the straw must ultimately be angled upwardly. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention dispenses upwardly angled straws from a gravity-fed dispenser by ejecting each straw over an inclined straw guide having walls shaped to guide the straw as it falls under the force of gravity into a dispensing aperture formed in the face of the dispenser. In this fashion, not only is the possibility of jamming alleviated, by properly shaping the aperture, the straw can be prevented from touching any surface which is accessible to—or touchable by—other customers. If desired, the dispenser can be provided with a dispense delay by which a second straw is not dispensed until a predetermined period after dispensing of the prior straw thus discouraging unnecessary use of straws. 
         [0006]    Other aspects and advantages of the present invention are described in the detailed description below and in the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The invention is described in detail below with reference to the appended drawings, wherein like numerals designate similar parts. In the Figures: 
           [0008]      FIG. 1  illustrates a straw dispenser of the present invention with a straw projecting upwardly through a dispensing aperture formed in the anterior housing plate without touching any surface which can be readily touched by customers. 
           [0009]      FIG. 2  is a partially cutaway schematic view of a straw dispenser of the present invention with both lateral housing walls removed to illustrate ejection of straws into the straw guide. 
           [0010]      FIG. 3  is a schematic view of the hopper portion of a straw dispenser of the present invention illustrating passage of straws from the hopper into the stacking slot. 
           [0011]      FIGS. 4-6  illustrate a preferred configuration for the straw guide used in the present invention. 
           [0012]      FIGS. 7-10  illustrate how a straw horizontally ejected from the straw ejection slot is reoriented by action of gravity into an upwardly inclined orientation in the straw guide. 
           [0013]      FIG. 11  is a partially exploded view illustrating the mechanism for ejection of straws into the straw guide. 
           [0014]      FIG. 12  illustrates a straw detector usable to detect the presence or absence of a straw in the straw guide. 
           [0015]      FIGS. 13 and 14  illustrate details of the drive paddle which ejects the straw from the straw ejection slot into the straw guide. 
           [0016]      FIGS. 15-17  illustrate another preferred configuration for the straw guide used in the present invention having a generally vertical posterior wall. 
           [0017]      FIGS. 18-20  illustrate another preferred configuration for the straw guide used in the present invention having a generally declivitous posterior wall. 
           [0018]      FIGS. 21-24  illustrate how a straw horizontally ejected from the straw ejection slot is reoriented by action of gravity into an upwardly inclined orientation in the alternative straw guide having a generally vertical posterior wall. 
           [0019]      FIG. 25  illustrates a mechanism for ejection of the straw into the straw guide in which the motor is placed above the drive belt. 
           [0020]      FIG. 26  is a logic flow diagram of an automated straw dispenser in which the system checks for a straw in the straw guide every t o  seconds and provides a delay of t i  seconds for dispensing of a second straw after the first has been removed. 
           [0021]      FIG. 27  is an alternate view, similar to a portion of  FIG. 11 , illustrating a pair of plates forming a tent-like shield over the straw guide to ensure that straws ejected from the stacking slot find their way into the straw guide. 
           [0022]      FIG. 28  is a three quarter schematic view of the interior mechanism of another straw dispenser of the present invention. 
           [0023]      FIG. 29  is side schematic view of the interior mechanism of another straw dispenser of the present invention. 
           [0024]      FIG. 30  is an isometric perspective of a traversing head. 
           [0025]      FIG. 31  is an isometric of a receiving tray. 
           [0026]      FIG. 32  is an isometric of a linear actuator. 
           [0027]      FIG. 33  is isometric of a thrust adjusting head. 
           [0028]      FIGS. 34-39  are schematic isometric perspective illustrating the straw dispensing operation when a linear actuator is used to propel the translating head along a rotating rod. In particular this sequence illustrates how straws are inherently ejected only one at a time with succeeding straws falling into position to be ejected only after the traversing head completes its cycles. 
           [0029]      FIG. 40  is a flow diagram for automatic straw dispenser systems using a traversing head which reciprocates along a shaft to eject straws from a hopper. 
           [0030]      FIG. 41  is an isometric perspective of a traversing head having an upwardly extending protuberance to impart a rocking motion to straws stacked in the dispensing slot. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0031]    The invention is described in detail below with reference to several embodiments and numerous examples. Such discussion is for purposes of illustration only. Modifications to particular examples within the spirit and scope of the present invention, set forth in the appended claims, will be readily apparent to one of skill in the art. Terminology used herein is given its ordinary meaning consistent with the exemplary definitions set forth immediately below. 
         [0032]    Straw dispenser  18  in  FIG. 1  comprises housing  20  of any convenient shape, often chosen primarily for marketing and aesthetic considerations to lend a modern or other desired appearance to the dispenser and comport with the overall atmosphere of the target restaurant market. In  FIG. 1 , straw dispenser  18  is provided with anterior housing plate  22  having dispensing aperture  24  therein. Protection for the interior mechanism is provided by housing top plate  26  and left lateral housing wall  28  and anterior front housing plate  22 . As is conventional, housing  20  will of course be provided with floor  37  as shown in  FIG. 2  and right lateral housing wall not shown herein. Straw  30  is dispensed though dispensing aperture  24  and projects upwardly therethrough. It has been found that presenting straw  30  projecting upwardly and outwardly from dispenser  20  makes it far more intuitive to customers to remove straws as some have difficulty if straw  30  is presented horizontally. It can be appreciated that even though straw  30  projects through dispensing aperture  24 , it does not touch any portion of anterior housing plate  22  and that it is generally quite difficult for customers to contaminate the interior of housing  20 . By proper choice of dimensions of dispensing aperture  24 , it is possible to discourage or entirely prevent users from touching any portion of automated dispenser  18  which touches straw  30 . These features overcome major drawbacks of previously available straw dispensers. 
         [0033]      FIG. 2  is a cutaway view of dispenser  18 , in which the principal components of the straw ejection system are depicted while  FIG. 3  illustrates hopper  31  in which straws  30  are stored above the mechanism illustrated in  FIG. 2  prior to dispensing. In  FIG. 2 , straws  30  to be dispensed are stacked vertically one above another adjacent vertically extending right stacking slot lateral wall  32  prior to being ejected seriatim into straw guide  34   b  which positions straws  30  projecting through dispensing aperture  24  by action of gravity. Motive force for ejection of straws is conveniently provided by drive paddles  38  connected to endless translating drive belt  36  by drive paddle necks  39  projecting laterally therefrom. It is considered quite advantageous for drive belt  36  to be disposed such that it translates in vertical planes as shown in  FIG. 2  as this limits interference with straw guide  34   b  and makes it possible to devote more of the interior volume of straw dispenser  18  to straw storage while reducing the overall height thereof. In particular, since hopper  31  defines a generally converging shape which is narrow at its lowest extremity and broadens upwardly, the space beneath either side of hopper  31  conveniently accommodates the upwardly opening drive belt  36 . In one sense, the surface of drive belt  36  can be considered mathematically to be a generalized cylinder wherein the generators of the cylinder extend generally vertically. 
         [0034]    In  FIG. 3 , hopper  31  for storing straws  30  prior to dispensation is defined forwardly of posterior housing plate  23  between inclined right hopper wall  33  adjoining right stacking slot vertical wall  32  and inclined left hopper wall  35  adjoining vertically extending left stacking slot lateral wall  50 . Access slot  52  is defined between left stacking slot vertical wall  50  and right stacking slot vertical wall  32  so that drive paddles  38  may be connected to drive belt  36  by drive paddle necks  39  extending therethrough. Conveniently, the lower extremity of right stacking slot vertical wall  32  presents a “J” shaped cross-section upon which straws  30  are supported prior to ejection from between stacking slot vertical walls  32  and  50 . Preferably, to aid in filling of hopper  31  by tilting of housing top plate  26 , the longitudinal dimension of hopper  31  is somewhat in excess of the length of straws  30  to be dispensed therefrom; but the maximum horizontal transverse dimension is less than the length of straws  30  to discourage straws  30  from lying with their longitudinal axes transverse to the width of hopper  31 . Upon closing of housing top plate  26 , lid close proximity sensors  27  are operatively connected to controller  70  ( FIGS. 11 and 25 ) which activates hopper vibrator  29  for a short period thereafter to allow straws  30  to rearrange themselves into a configuration in which the axes thereof are oriented parallel both to each other and to the longitudinal axis of hopper  31  presenting a compact downwardly flowing disposition relative to each other for eased dispensation. Preferably, top plate  26  is bowed upwardly to present a hollow cavity above hopper  31  and limit or discourage jamming of an excessive number of straws  30  into hopper  31  which might lead to jamming. 
         [0035]    In  FIG. 2 , straw guide  34   b  is depicted having a declivitous forwardly sloping rear wall  40   b  as detailed in  FIGS. 18-20 .  FIGS. 4 through 6  illustrate an alternative straw guide  34  having a relieved rear wall  40  which obviates the possibility of straw  30  becoming lodged there against as it falls into the dispensing position as illustrated in  FIGS. 7 through 10 . In  FIGS. 4 through 6 , inclined left lateral guide wall  42  cooperates with inclined right lateral guide wall  44  to urge straw  30  into centrally located straw retention trough  46  with the midpoint of straw  30  located inwardly and posteriorly to straw retention ledge  48  which as illustrated in  FIGS. 7 through 10  serves as a pivot point upon which straw  30  reorients itself upon clearing relieved rear guide wall  40  to fall into an upwardly and outwardly projecting disposition to be ready for dispensation through dispensing aperture  24 . 
         [0036]      FIGS. 11 through 14  further illustrate details of the mechanism by which straws  30  are ejected from between right stacking slot lateral wall  32  and left stacking slot lateral wall  50  (shown in phantom in  FIG. 11 ). Longitudinal motion of straws  30  between stacking slot vertical walls  32  and  50  is restrained by stacking slot anterior vertical wall  54  and stacking slot posterior wall  56 , while straws  30  are ejected through ejection opening  58  in stacking slot anterior vertical wall  54 . As drive belt  36  translates, necks  39  of drive paddles  38  progressively pass through access opening  60  in stacking slot posterior wall  56 , access slot  52  (shown more clearly in  FIGS. 13 and 14 ) and ejection opening  58  through stacking slot anterior wall  54 , yet straws  30  are confined to pass only through ejection opening  58  in stacking slot anterior wall  54 . Drive paddles  38  preferably have extension guide tabs  74  formed thereupon riding in extension guide groove  72  in right stacking slot lateral wall  32  ensuring that drive paddles  38  cannot be lodged into the rear opening of straws  30  as each is propelled forwardly though ejection opening  58  by pressure from drive paddle  38 . 
         [0037]    When straw  30  is removed through dispensing aperture  24 , its absence or presence may be detected by either a transmissive or reflective light detection sensor. In  FIG. 11 , reflective light detection sensor  64  is illustrated, in which as shown in  FIG. 12 , detects the absence of reflected light from LED light source  66  and, working through controller  70 , photoreceptor  68  activates motor  62  driving drive belt  36  and drive paddles  38  for either a predetermined drive time or until straw  30  is ejected into guide tray  34  with the presence of reflected light being again detected inactivates motor  62  until currently presented straw  30  is removed triggering another cycle. In the event that excessive time passes between detection of absence of a straw  30  in guide tray  34  and movement of another straw  30  into dispensing position, hopper vibrator  29  is temporarily activated to reorient straws  30  disposed in hopper  31 , allowing a straw  30  to fall into ejection position and thereafter be ejected into guide tray  34  when motor  62  is reactivated. If after an appropriate number of cycles, no straw has been delivered into ejection position, cycling is interrupted and an audible or visual signal (not shown) is activated to alert restaurant staff that attention is required to refill hopper  31 . As mentioned above, hopper  31  has inwardly sloping smooth walls with dimensions being chosen to urge straws  30  within hopper  31  to align themselves by action of gravity into a configuration in which the longitudinal axes of all straws  30  are parallel to one another to restrict attention to the dispenser being required except in situations in which hopper  31  must be refilled. Preferably, the presence or absence of straw  30  in dispensing trough  46  is detected by detectors having no moving parts to increase the reliability of the overall system. A more preferred sensor configuration is shown in  FIGS. 15 through 17  in which drive motor  62  is activated by the presence of a light signal from source  66   a  being received by light detector  68   a  as is occasioned by absence of straw  30  in straw retention trough  46 . As sensor  68   a  and source  66   a  are vertically disposed on either lateral side of straw retention trough  46 , the possibility of occlusion by dusting or other debris is reduced. In  FIGS. 15 through 17 , guide tray  34   a  having generally vertical rear wall  40   a  is depicted, structures analogous to those shown in  FIGS. 4-10  bearing similar numbers with a suffix “a” appended thereto, i.e.  42   a,    44   a,    46   a  and  48   a.  So long as straw  30  is advanced beyond rear wall  40   a  during the drive portion of the cycle, provision of a generally vertical rear wall  40   a  for straw guide  34   a  is entirely satisfactory. As shown in  FIGS. 2 ,  11  and  25 , use of upwardly opening drive belt  36  in the form of a generalized cylinder having generally vertical generators makes it possible to easily locate drive belt  36  horizontally adjacent to access slot  52  which serves to eject straws  30  into dispensation position without interference between drive belt  36  and straw guide  34 . In  FIGS. 18 through 20 , straw guide  34   b  is depicted having forwardly inclined declivitous rear wall  40   b.  As before, use of vertically opening drive belt  36  makes it easy to avoid interference between the straw ejection mechanism and straw guide  34   b  while enabling straw hopper  31  to be located closely adjacent to anterior housing plate  22 , less than one straw length away, and reduces the height of the dispensing portion of the dispenser. In preferred embodiments, straw hopper  31  is located closely adjacent to anterior housing plate  22  being less than three quarters of a straw length away, more preferably just slightly over half a straw length away. In preferred embodiments, straw hopper  31  is located closely adjacent to anterior housing plate  22  being less than three quarters of a straw length away, more preferably just slightly over half a straw length away. 
         [0038]      FIGS. 21 through 24  illustrate how straw  30  is guided into straw retention trough  46   b  by action of gravity once rear edge of straw  30  is urged past rear wall  40   b  with the center of gravity of straw  30  being located posteriorly with respect to straw retention ledge  48   b  allowing straw  30  to pivot downwardly against inclined left lateral guide wall  42   b  which cooperates with inclined right lateral guide wall  44   b  to urge straw  30  into centrally located straw retention trough  46   b  with the midpoint of straw  30  located inwardly and posteriorly to straw retention ledge  48 . In  FIGS. 21 through 24 , reflected light sensor  64   b  combines both a light source, conveniently an LED, and a receiver that detects the absence of light reflected from straw  30  alerting controller  70  to impel another straw  30  into dispensation position resting in straw retention trough  46   b  in guide tray  34   b.  As sensor  64   b  is located horizontally adjacent to straw  30 , a vertical aspect is presented reducing possibility of occlusion by dusting or the like. 
         [0039]      FIG. 25  illustrates an alternative internal configuration for automated dispenser  18  in which drive motor  62  is placed above drive belt  36 . 
         [0040]      FIG. 26  is a logic flow diagram for controller  70  illustrating its programming to control operation of belt drive motor  62  and hopper vibrator  29  in response to inputs from door close detection switches  27  and straw sensor  64 . Conveniently, controller  70  can be programmed to check for the presence of straw  30  in position for dispensation periodically, every t 0 , where t 0  is a conveniently small fraction of a second and to operate hopper vibrator  29  for a suitable period of time to facilitate rearrangement of straws  30  in hopper  31  so that the axes thereof are parallel to each other but to shut off and provide an attention signal if movement of a straw  30  into dispensation position has not been triggered after a suitable number of attempts. 
         [0041]      FIG. 27  illustrates an alternative internal configuration for automated dispenser  18  in which plates  76  and  78  (with  78  being shown in phantom) above guide tray  34  ensure that straws ejected find their way into dispensing aperture  24  by forming a chute to guide ejected straws into dispensing aperture  24  and prevent them from being displaced laterally or vertically from the path leading from ejection opening  58  through stacking slot anterior wall  54 . In  FIG. 27 , there is also pictured a non-contact sensing mechanism  80  which initiates the “Activate Straw Advance” protocol shown in  FIG. 26  only if a hand is waved in front of dispenser  18 . Such non-contact sensing mechanisms are well known as discussed in U.S. Pat. No. 8,186,551 B2, Morris, et al. presenting a very thorough review of known non-contact sensing mechanisms. Known mechanisms can be quite energy efficient allowing for power by hardwiring or from batteries. 
         [0042]      FIGS. 28 and 29  illustrate the interior mechanism of another straw dispenser of the present invention differing from those embodiments previously disclosed in that a threadless linear actuator  61  encompassed within, and therefore not visible, traversing head  183  disposed on rotable shaft  191  is used to advance ejection rod  184  carried on a reciprocating traversing head  183 . A typical linear actuator  61  is illustrated in  FIG. 32 . Such threadless linear actuators are well known items of commerce and are described in U.S. Pat. No. 3,272,021; U.S. Pat. No. 3,425,284; U.S. Pat. No. 4,191,059; U.S. Pat. No. 4,224,831; U.S. Pat. No. 4,726,242; U.S. Pat. No. 4,411,166. In brief, these linear actuators employ skewed roller members arranged about and engaging a drive shaft to translate rotation of the drive shaft to linear displacement along the shaft. One particular brand of linear actuators are sold under the trademark Roh&#39;Lix by Zero-Max, Inc., 13200 Sixth Avenue North, Plymouth, Minn. 55441. In  FIGS. 28 and 29 , hopper  171  is configured similarly to the hopper in previous embodiments so that a J-shaped ledge is formed at the bottom of the right wall of hopper  32  to retain the lowermost straw  30  thereupon while ejection rod  184  carried on traversing head  183  protrudes into access slot  52 . As shown in  FIGS. 34-39 , ejection rod  184  riding in engagement slot  52  has considerable length so that as straw  30  is ejected, straw  30  above it is still supported by ejection rod  184  and so does not move into ejection position until after traversing head  183  has activated forward limit switch  199 , which signals the controller to reverse motor module  187  reversing the direction of rotation of shaft  191  so that traversing head  183  is returned to its rest position engaging rear limit switch  199 . 
         [0043]      FIG. 30  illustrates traversing head  183  having thrust adjustment head  159  surrounding rotary traversing rod aperture  180  through which rotary traversing rod  191  passes. In some embodiments, auxiliary support rod  197  passing through support aperture  178  may be employed to support the weight of traversing head  183 . In many cases, the weight of traversing head  183  will be sufficiently low that auxiliary support rod  197  may be dispensed with. Ejection rod  184  traverses the length of engagement slot  52  as traversing head  183  traverses along rotary traversing rod  191 . Significantly ejection rod  184  is of significant length so that as discussed above, when straw  30  is being ejected, straws above cannot fall into dispensing position until lowermost straw  30  has been ejected and traversing head  183  has retraced its path and cleared the posterior end of engagement slot  52 . 
         [0044]      FIG. 31  illustrates yet another design for a guide tray  34  to receive and properly orient straws  30  after ejection from hopper  31 . Significantly, in the design depicted in  FIGS. 28 and 29 , straws  30  penetrate dispensing aperture  24  while being ejected from hopper  31  and the rear ends of straws  30  fall backward into guide tray  34  only after the straw is ejected from hopper  31 . 
         [0045]      FIG. 33  illustrates a known thrust adjusting head  159  usable to adjust the force with which conventional linear actuator  61  shown in  FIG. 32  engages rotary drive shaft  191 . 
         [0046]      FIGS. 34-39  illustrate details of the interaction between straws  30  in stacking slot  51 , defined between sidewalls  32  and  50 , as traversing head  183  traverses dispensing slot  52  to dispense straws  30  seriatim. In  FIG. 34 , two straws  30  are stacked one atop another in stacking slot  51  while traversing head  183  is in its rearmost position engaging rear detection switch  199  (not shown in this sequence). Upon receipt of a signal to dispense another straw  30 , traversing head  183  moves forwardly forcing lower straw  30  out of stacking slot  51 , through dispensing aperture  24  (see  FIG. 28 ). As straw  30  clears slot  51 , ( FIGS. 35 and 36 ), the rear of straw  30  is no longer supported by sidewall  32  lower lip and begins to fall into dispensing tray  34 , ( FIGS. 37 and 38 ) while the forwardmost portion of straw  30  above it still rests upon traversing head  183 . After traversing head  183  engages forward limit switch  199 , it moves rearwardly until it engages rear limit switch  199  and straw  30  above it can now fall into position to be dispensed as shown in  FIG. 39 . 
         [0047]      FIG. 40  is a flow diagram illustrating the logic by which movement of traversing head  183  is controlled in response to activation of the two limit switches  199  and the straw detection sensor deployed in tray  34 . 
         [0048]      FIG. 41  illustrates an alternative traversing head having upwardly extending protuberance  186  formed on pusher rod  184 . Upwardly extending protuberance  186  imparts a rocking motion to straws  30  thereabove as it transits the length of slot  52  helping to agitate them to ensure that they fall into position properly for dispensing. Another method of agitating straws  30  includes the hopper vibrator  29  discussed above. 
         [0049]    While the invention has been described in detail, modifications within the spirit and scope of the invention will be readily apparent to those of skill in the art. In view of the foregoing discussion, relevant knowledge in the art and references discussed above in connection with the Background and Detailed Description, the disclosures of which are all incorporated herein by reference, further description is deemed unnecessary. In addition, it should be understood that aspects of the invention and portions of various embodiments may be combined or interchanged either in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention.