System for palletizing screws and other headed elements

Information

  • Patent Grant
  • 6729111
  • Patent Number
    6,729,111
  • Date Filed
    Friday, August 2, 2002
    22 years ago
  • Date Issued
    Tuesday, May 4, 2004
    20 years ago
  • Inventors
  • Examiners
    • Gerrity; Stephen F.
    • Desai; Hemant
    Agents
    • Armstrong, Kratz, Quintos, Hanson & Brooks, LLP
Abstract
A machine for palletizing elements having a head, a shank and a tip. An auger has a first portion having a variable pitch and a second portion having a constant pitch. A plurality of the elements are directed onto the auger and retained on the auger. A transfer arm moves the plurality of elements from the auger and introduces the plurality of elements to a tray having rows of holes therein. Several embodiments are disclosed.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a system for palletizing screws and more particularly to an apparatus which automatically and rapidly loads screws or other headed elements into holes in a tray.




2. Description of Related Art




Screws and similar elements having heads, shanks and tips have been loaded into trays so that subsequent batch processing operations can proceed. These operations include the application of paint or other coatings onto the screw head area; and moving the screws through heat treating ovens. Up until now, the trays have been loaded either by hand, or by the use of shaker tables, where, it was hoped, a percentage of the screws would end up with their shanks hanging through the tray's holes. But both methods have proven to be very labor-intensive.




BRIEF SUMMARY OF THE INVENTION




It is an object of the present invention to automatically and rapidly load headed elements such as screws into a series of holes in a tray.




It is a further object of the present invention to align a plurality of screws in a row and, transfer the entire row, simultaneously to holes in a tray.




In accordance with the teachings of the present invention there is disclosed a machine for palletizing screws and other elements having a head, a shank and a tip. The machine has an auger having a variable pitch. Means are provided for feeding a plurality of screws, in sequence, onto the auger. A transfer arm has means thereon to remove the screws from the auger. Means are provided for moving the transfer arm to and from the auger. Means are provided for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein. The screws are automatically and rapidly received in the holes in the tray.




In further accordance with the teachings of the present invention, there is disclosed a machine for palletizing screws and other elements having a head, a shank and a tip. The machine has an auger having a first portion and a second portion. The first portion has a variable pitch, the second portion has a constant pitch. Means are provided for feeding a plurality of screws, in sequence, onto the auger. A vane is disposed adjacent to the first portion of the auger, the vane directing each screw onto the first portion of the auger. A transfer arm has means thereon to remove the screws from the auger. The transfer arm is movable with respect to the auger. Means are provided for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein. The shanks of the screws are automatically and rapidly received in the holes in the tray.




In still further accordance with the teachings of the present invention, there is disclosed a machine for palletizing screws and other elements having a head, a shank and a tip. The machine has a first auger having a first portion and a second portion. The first portion has a variable pitch, the second portion has a constant pitch. Means are provided for feeding a plurality of screws, in sequence, onto the auger. A second auger is disposed adjacent and parallel to the first auger. The second auger directs the head of each screw onto the first portion of the first auger. A transfer arm has means thereon to remove the screws form the first auger. The transfer arm is movable with respect to the first auger. Means are provided for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein. The shanks of the screws are automatically and rapidly received in the holes in the tray.




In yet further accordance with the teachings of the present invention, there is disclosed a machine for palletizing screws and other elements having a head, a shank and a tip. The machine has a first auger having a first portion and a second portion. The first portion has a variable pitch, the second portion has a constant pitch. Means are provided for feeding a plurality of screws, in sequence, onto the first auger. A second auger is disposed below and parallel to the first auger. A third auger is disposed above and parallel to the first auger. All three augers are rotated in the same direction. The head of each screw contacts the third auger, the shank of each screw contacts the first auger and the tip of each screw contacts the second auger. A transfer arm has means thereon to remove the screws from the augers, the transfer arm is movable with respect to the augers. Means are provided for removing the screws form the transfer arm and introducing the screws into a tray having a plurality of holes therein. The shanks of the screws are automatically and rapidly received in the holes in the tray.




Moreover, in accordance with the teachings of the present invention, there is disclosed a machine for palletizing screws and other elements having a head, a shank and a tip. The machine has a first auger having a first portion and a second portion. The first portion has variable pitch, the second portion has a constant pitch. A second auger is disposed adjacent and parallel to the first auger, the second auger being in the same vertical plane as the first auger. Means are provided for feeding a plurality of screws, in sequence, onto the augers. At least one upper drum is disposed above the first auger, the heads of the screws being received in the at least one upper drum. At least one lower drum disposed below the second auger, the tips of the screws having received in the at least one lower drum. Means are provided for rotating the at least one upper drum and the at least one lower drum in synchronization wherein the plurality of screws are displaced from the augers. A plurality of down tubes are disposed beneath the augers wherein the screws are directed to a tray having a plurality of holes therein. The screws are automatically and rapidly received in the holes in the tray.




These and other objects of the present invention will become apparent from a reading of the following specification taken in conjunction with the enclosed drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a top plan schematic view of the machine of the present invention.





FIG. 2

is a top plan view of an auger having a first portion and a second portion.





FIG. 3

is a perspective view having screws stretched out in the first portion of the auger.





FIG. 4

is a perspective view of the transfer arm distal from the auger.





FIG. 5

is a perspective view showing means for moving the transfer arm proximal to the auger.





FIG. 6

is a perspective view showing screws falling into drum holes leading to split funnels.





FIG. 7

is a perspective view showing pocket pins projecting upwardly through holes in the tray.





FIG. 8

is a side elevation view showing a screw being directed by a pocket pin.





FIG. 9

is a prospective view showing a chain drive conveyer.





FIG. 10

is a perspective view of a portion of the tray.





FIG. 11

is a perspective view showing the spring-loaded blade on the in-line vibratory feeder.





FIG. 12

is a perspective view showing a vane adjacent to the first portion of the auger.





FIG. 13

is a perspective view showing a second auger adjacent to the auger.





FIG. 14

is a perspective view showing the machine having three augers.





FIG. 15

is a perspective view showing a wrap finger directing the screws onto the auger.





FIG. 16

is a diagram showing a machine having two augers and drums to remove screws from the augers.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring now to

FIG. 1

, a single unit of the machine of the present invention has a vibratory bowl feeder


10


into which a plurality of screws


12


are loaded in random order. Preferably all of the screws are of the same size and type so that the palletized product has all identical screws. As used herein, “screws” includes any element with a head


14


, connected to a shank


16


which has a tip


18


. For convenience of expression, “screw” as used herein includes headed elements with and without threaded shanks. Further included are elements with and without slots in the head and heads which are circular or have flat sides to cooperate with a wrench. The output of the vibratory bowl feeder


10


is directed to an in-line vibratory linear feeder


20


where the screws are separated and disposed on a moving surface leading from the vibratory bowl feeder


10


to sorting and loading position of the machine as will be described. It is noted that for high volume production, a number of the single units may be used. The following description is for a single unit.




The in-line vibratory linear feeder


20


carries the screws


12


to an auger


22


. Preferably the auger has a first portion


24


and a second portion


26


(FIG.


2


). The auger


22


may be approximately 30 inches in length. The first portion


24


may be approximately 10 inches in length. The first portion


24


has a variable pitch, the pitch increasing in length as the screws


12


proceed down the length of the first portion


24


. The second portion


26


has a constant pitch. As the screws


12


approach the first portion


24


of the auger


22


, the head of the screw contacts the thread on the rotating auger


22


, the screw


12


is stripped off from the linear feeder


20


and is moved along the auger toward the second portion


24


. Successive screws are each separately moved along the auger


22


. Due to the variable pitch of the first portion


24


, the screws


12


are stretched out in their spacing (FIG.


3


). The final spacing of the screws is determined by the spacing of holes in a tray as will be described. The screws


12


are moved onto the second portion


26


of the auger


22


which has a constant pitch and the screws


12


are equidistant from the adjacent screws. It is preferred that the second portion


26


of the auger


22


have a length to receive twenty (20) screws.




As shown in

FIG. 4

, a transfer arm


28


is disposed opposite the auger


22


and is movable to and from the auger


22


. It is preferred that the transfer arm


28


ride on a cam


30


. The shape of the cam


30


is such that the transfer arm


28


is adjacent to the auger


22


for a very brief period of time. The transfer arm


28


has means thereon to remove the screws


12


from the second portion


26


of the auger


22


. In a preferred embodiment, the transfer arm


28


has a plurality of spaced-apart magnets


32


mounted on the transfer arm. The spacing between the magnets


32


corresponds to the spacing of the screws


12


on the second portion


26


of the auger


22


. The transfer arm is moved on the cam


30


so the magnets


32


contact the screws


12


and attract the screws


12


from the auger


22


. Pressure is applied to the follower against a sudden rise on the cam


30


which momentarily slows or stalls rotational movement of the auger


22


at the same time as the magnets


32


attract the screws


12


. This is accomplished by a slip clutch


34


in the drive train (FIG.


5


).




Alternately, other means for removing the screws


12


from the auger and picking up of the screws


12


by the transfer arm


28


which are known to persons skilled in the art, may be used. Mechanical means such as clamps or jaws may be carried by the transfer arm


28


. Also, pneumatic means such as vacuum outlets on the transfer arm


28


may draw the screws


12


from the auger


22


and hold the screws on the transfer arm


28


.




The transfer arm


28


is moved away from the auger


22


by the drive train and the screws


12


are released from the transfer arm


28


. The nature of the release of the screws is dependent on the holding means. Any means known to persons skilled in the art may be used. For example, but not limiting, the magnetic attraction of the screws


12


may be broken by a mechanically driven pusher which is extendable from beneath the magnet


32


to strike the screw


12


and break the magnetic attraction. The screws


12


may be exposed to an electric shock to break the magnetic attraction. Mechanical clamps or jaws may be opened to release the screws


12


. Vacuum may be interrupted to release the screws


12


.




The screws


12


are all released simultaneously and each screw


12


falls into a respective down tube


36


immediately below the transfer arm


28


(FIG.


6


).




At the bottom of each down tube


36


, there is a corresponding split funnel


38


. The split funnel


38


is formed of two mirror image half funnels which may be separated. When closed, the shanks


16


of the screws


10


extend into the stem of the funnel


38


and the heads


14


of the screws


12


are too large to pass into the funnel stem. The split funnels


38


are opened to release the screw heads


12


and the shanks


16


of the screws


12


drop directly into corresponding holes


40


in a tray


42


which is disposed under the funnels.




In order to more positively guide the shanks


16


of the screws


12


into the holes


40


, pocket pins


44


are removably disposed through the row of holes


40


in the tray


42


. Each pocket pin


44


is a rod having a cavity in the upper end. The tips


18


of the screws


12


are received in the respective cavities and, as the pocket pins


44


are withdrawn from the holes


40


in the tray


42


. The shanks


16


of the respective screws


12


are directed into the holes


40


(FIG.


8


).




In this manner, a tray


42


having any desired number of screws


12


may be palletized. The tray is palletized when the hole on the tray are fully loaded and available for stacking, storage or further treatment. Further treatment includes, but is not limited to, painting the heads and/or heat treating the screws. It is preferred that twenty (20) screws be disposed on the second portion of the auger


22


, all being moved by the transfer arm


28


and dropped into the split funnels


38


. In this manner, twenty holes


40


are filled in the tray


42


in a single transfer. Thus, a tray


42


having fifty (50) parallel rows containing twenty (20) screws per row is a convenient and practical size.




In order to incrementally move the tray


42


so that a succeeding row of holes


40


may be filled, an indexing means is provided. The indexing means may be a ratchet driven chain conveyor


46


(FIG.


9


). Alternately, the indexing means may be at least one opening


48


formed in a base flange on the tray


42


(FIG.


10


). A pin


50


extending upwardly from a chain drive


46


engages the opening


48


and moves the tray


42


by a desired distance at which point the pin


50


is disengaged from the opening


48


in the base flange. The indexing means is not limited to the examples described herein but may be indexing means known to persons skilled in the art. The indexing means may include, but not be limited to, indexing belt drives, cranks and pawls.




The holes


40


in the tray


42


preferably are arranged in a series of parallel rows. Preferably, adjacent rows are offset from each other and alternate rows are in alignment with each other (FIG.


10


). The indexing means incrementally moves the tray


42


a distance equal to the space between the rows. Also, the tray


42


is moved back and forth sideways as it is indexed along. The amount of sideway movement is equal to the offset distance between adjacent rows. It is not essential that the adjacent rows be offset from each other, the rows may all be aligned. Offset orientation is useful for painting the heads of the screws


12


to reduce the amount of paint required.




In a preferred embodiment, the machine loads


420


screws per minute into the tray


42


. A plurality of trays


42


are fed sequentially through the machine so there is no interruption to the filling. The holes


40


on the loading edge and the trailing edge of each tray are spaced one-half of the spacing between the rows of holes so that when two trays are butted together, the spacing between the rows remain constant despite the rows being in adjoining trays.




It is preferred that the in-line vibratory feeder


20


have a spring-loaded blade


52


disposed at the stripping off point where the vibratory feeder


20


adjoins the first portion


24


of the auger


22


(FIG.


11


). The spring-loaded blade


32


urges each screw onto the thread of the auger in a desired orientation and holds each screw on the rotating auger for a sufficient period to assure the retention of the screw. In the event that a screw is improperly oriented, the spring-loaded blade urges the screw onto the auger and permits potential jams to clear themselves and not to interrupt the production cycle.




In one embodiment, a vane


54


is disposed adjacent to the first portion


24


of the auger


22


. The vane


54


directs the head


14


of each screw


12


onto the first portion


24


of the auger as shown in FIG.


12


.




A second embodiment provides a second opposed auger


56


disposed adjacent to and parallel to the auger


22


. The augers are in the same horizontal plane. The augers


56


,


22


rotate in opposite directions. The second auger


56


directs the heads


14


of the screws onto the first portion


24


of the auger


22


as shown in FIG.


13


.




A third embodiment has three augers. The first auger


22


has a variable pitch first portion


24


and a constant pitch second portion


26


. A second auger is disposed below and parallel to the first auger


22


. A third auger


60


is disposed above and parallel to the first auger


22


. All three augers rotate in the same direction. The head


24


of the screw


12


contacts the third auger


60


, the shank


66


of the screw


12


contacts the first auger


22


, and the tip


18


of the screw


12


contacts the second auger


60


(FIG.


14


). Preferably, the three augers are not exactly vertically aligned but are inclined with respect to a vertical axis. The inclination prevents the screws from falling off of the augers. Although the angle of inclination is not critical, an angle of approximately 20° is preferred.




In the third embodiment, a wrap finger


62


is connected to the in-line vibratory feeder


20


at the stripping off point adjacent to the first portion


24


of the auger


22


as shown in FIG.


15


. The wrap finger


62


is a curved finger which contacts the shank


16


of the screw as the screw


12


exits the vibratory feeder


20


. The wrap finger has an upward curvature and directs the head


14


each successive screw toward the thread on the auger to align the screw on the auger


22


. Thus, each screw


14


is rotated for the selected position to be seated on the auger


22


.




In another embodiment, the machine does not have a transfer arm. As shown in

FIG. 16

, a first auger


22


has a first portion


24


with a variable pitch and a second portion


26


with a constant pitch. A second auger


64


having a constant pitch is disposed adjacent to and parallel to the first auger


22


. The augers are in the same vertical plane and rotate in the same direction. At least one upper drum


66


is disposed above the first auger


22


. The heads


14


of the screws


12


are received in the at least one upper drum


66


. At least one lower drum


68


is disposed below the second auger


64


. The tips


18


of the screws


12


are received in the at least one lower drum


68


. Preferably, each drum


66


,


68


has a notch formed therein to engage the screw


12


to more easily displace the screw


12


. Means are provided for rotating the at least one upper drum


66


in synchronization with the at least one lower drum


66


. When the drums


66


,


68


are rotated, the plurality of screws


12


which are carried by the augers


22


,


64


are displaced from the augers


22


,


64


and the screws


12


fall into down tubes


36


as described above for the other embodiments. The down tubes


36


, split funnels


38


and trays


42


are the same as described above for palletizing the screws. This embodiment does not have any magnets and can be used for headed elements which are made of non-magnetic materials such as brass and aluminum.




The present invention overcomes the labor intensive sorting and palletizing of headed elements which has been used to date. The present machine is useful with screws, bolts, nails, and other headed elements. The present invention can be made with augers having any desired pitch to be used with headed elements of any length and diameters.




Obviously, many modifications may be made without departing from the basic spirit of the present invention. Accordingly, it will be appreciated by those skilled in the art that within the scope of the appended claims, the invention may be practiced other than has been specifically described herein.



Claims
  • 1. A machine for palletizing screws and other elements having a head, a shank and a tip, the machine comprising:an auger having a variable pitch, means for feeding a plurality of screws, in sequence, onto the auger, a transfer arm having means thereon to remove the screws from the auger, means for moving the transfer arm to and from the auger, means for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein, wherein the screws are automatically and rapidly received in the holes in the tray.
  • 2. The machine of claim 1, wherein the means for feeding the plurality of screws, in sequence, onto the auger is a vibratory bowl feeder which directs the screws onto an in-line vibratory feeder, the in-line vibratory feeder carrying the screws to the auger.
  • 3. The machine of claim 2, further comprising a spring-loaded blade urged against the screws on the in-line feeder such that screws are fed onto the auger without jamming.
  • 4. The machine of claim 1, wherein the auger has a first portion connected to a second portion, the first portion having a first length having a variable pitch, the second portion having a second length having a constant pitch wherein the spacing of the screws are stretched out to a desired distance on the first portion of the auger and are maintained at the desired distance on the second portion.
  • 5. The machine of claim 1, wherein the transfer arm has means thereon to remove the screws from the auger and to release the screws from the transfer arm.
  • 6. The machine of claim 5, wherein the means to remove and release the screws are magnetic.
  • 7. The machine of claim 5, wherein the means to remove and release the screws are mechanical.
  • 8. The machine of claim 5, wherein the means to remove and release the screws are pneumatic.
  • 9. The machine of claim 1, wherein the means to move the transfer arm is a driven cam on which the transfer arm rides.
  • 10. The machine of claim 1, further comprising a plurality of down tubes disposed under the transfer arm wherein the plurality of screws are released from the transfer arm, each screw being directed into a separate down tube, each down tube being disposed over a respective split funnel such that each screw is received in a separate split funnel, the split funnels each being disposed over a respective hole in the tray, such that opening the split funnel deposits each of the screws in a respective opening in a row of holes in the tray.
  • 11. The machine of claim 10, further comprising a plurality of spaced-apart pocket pins removably disposed through the row of holes in the tray, each pocket pin contacting the tip of a respective screw wherein the shanks of the screws are directed into the holes in the tray as the pocket pins are withdrawn from the row of holes in the tray.
  • 12. The machine of claim 1, wherein a vane is disposed adjacent to the first portion of the auger, the vane directing each screw onto the first portion of the auger.
  • 13. The machine of claim 1, wherein a second opposed auger is disposed adjacent and parallel to the auger, the augers being in the same horizontal plane, the augers rotating in opposite directions, the second auger directing the head of each screw onto the first portion of the auger.
  • 14. The machine of claim 1, further comprising a second auger disposed below and parallel to the auger, a third auger disposed above and parallel to the auger, all three augers being rotated in the same direction, wherein the head of each screw contacts the third auger, the shank of each screw contacts the auger and tip of each screw contacts the second auger.
  • 15. The machine of claim 14, further comprising a wrap finger connected to an in-line vibratory feeder disposed adjacent to the auger, the wrap finger rotating the screws to a selected position for seating on the augers.
  • 16. The machine of claim 1, wherein the holes in the tray are arranged in a series of parallel rows having a space therebetween, the adjacent rows being offset a predetermined distance and alternate rows being in alignment, the machine having an indexing means wherein the tray is incrementally moved forwardly a distance equal to the space between the rows and the tray is moved sideways a distance equal to the offset disposition of adjacent rows.
  • 17. A machine for palletizing screws and other elements having a head, a shank and a tip, the machine comprising:an auger having a first portion and a second portion, the first portion having a variable pitch, the second portion having a constant pitch, means for feeding a plurality of screws, in sequence, onto the auger, a vane disposed adjacent to the first portion of the auger, the vane directing each screw onto the first portion of the auger, a transfer arm having means thereon to remove the screws from the auger, the transfer arm being movable with respect to the auger, means for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein wherein the shanks of the screws are automatically and rapidly received in the holes in the tray.
  • 18. A machine for palletizing screws and other elements having a head, a shank and a tip, the machine comprising:a first auger having a first portion and a second portion, the first portion having a variable pitch, the second portion having a constant pitch, means for feeding a plurality of screws, in sequence, onto the auger, a second auger disposed adjacent and parallel to the first auger, the second auger directing the head of each screw onto the first portion of the first auger, a transfer arm having means thereon to remove the screws from the first auger, the transfer arm being movable with respect to the first auger, means for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein wherein the shanks of the screws are automatically and rapidly received in the holes in the tray.
  • 19. A machine for palletizing screws and other elements having a head, a shank and a tip, the machine comprising:a first auger having a first portion and a second portion, the first portion having a variable pitch, the second portion having a constant pitch, means for feeding a plurality of screws, in sequence, onto the first auger, a second auger disposed below and parallel to the first auger, a third auger disposed above and parallel to the first auger, all three augers being rotated in the same direction, wherein the head of each screw contacts the third auger, the shank of each screw contacts the first auger and the tip of each screw contacts the second auger, a transfer arm having means thereon to remove the screws from the augers, the transfer arm being movable with respect to the augers, means for removing the screws from the transfer arm and introducing the screws into a tray having a plurality of holes therein, wherein the shanks of the screws are automatically and rapidly received in the holes in the tray.
  • 20. The machine of claim 1, further comprising a wrap finger connected to an in-line vibratory feeder disposed adjacent to the third auger, the wrap finger rotating the screws to a selected position for seating on the augers.
  • 21. A machine for palletizing screws and other elements having a head, shank and a tip, the machine comprising:a first auger having a first portion and a second portion, the first portion having a variable pitch, the second portion having a constant pitch, a second auger disposed adjacent and parallel to the first auger, the second auger being in the same vertical plane as the first auger, means for feeding a plurality of screws, in sequence, onto the augers, at least one upper drum disposed above the first auger, the heads of the screws being received in the at least one upper drum, at least one lower drum disposed below the second auger, the tips of the screws being received in the at least one lower drum, means for rotating the at least one upper drum and the at least one lower drum in synchronization wherein the plurality of screws are displaced from the augers, a plurality of down tubes disposed beneath the augers wherein the screws are directed to a tray having a plurality of holes therein, wherein the screws are automatically and rapidly received in the holes in the tray.
CROSS REFERENCE

This application is related to provisional patent application Ser. No. 60/312,660 filed Aug. 15, 2001, entitled “Automated System for Palletizing Screws and Other Headed Elements”.

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Provisional Applications (1)
Number Date Country
60/312660 Aug 2001 US