Machine that ties and unties a four-in-hand necktie knot

Information

  • Patent Grant
  • 6820904
  • Patent Number
    6,820,904
  • Date Filed
    Monday, March 3, 2003
    21 years ago
  • Date Issued
    Tuesday, November 23, 2004
    19 years ago
  • Inventors
  • Examiners
    • Welch; Gary L.
    Agents
    • Hollander Law Firm, P.L.C.
Abstract
A machine for automatically tying a four-in-hand necktie knot in a necktie, includes (1) a horizontal rotatable cylinder; (2) a hooking mechanism capable of pulling a left hand short segment of the necktie through a loop of a right hand long segment of the necktie hanging from the rotatable cylinder; (3) a finger mechanism capable of laterally moving the right hand long segment along the length of the rotatable cylinder; (4) a whirler mechanism capable of flipping an end of the right hand long segment around the rotatable cylinder and up through a space between the right hand long segment and the left hand short segment and the necktie support, and (5) an electronic and feedback control for operating various mechanisms in response to a sequence of voltage commands.
Description




BACKGROUND AND SUMMARY OF INVENTION




I have conceived, built, and successfully operated a machine that ties and then unties a necktie, using a four-in-hand necktie knot. The machine consists of 10 different electric motors that are coordinated by a computer so as to perform the above tasks on a tie hung from a platform located above the motors. The purpose of the machine is for entertainment although in principle, after the tie is tied, it could be removed from the platform and hung on a person's neck as if it had been manually tied.




Each of the ten electric motors has an integral gearhead whose output shaft is attached to a potentiometer that provides feedback to an electronic power operational amplifier that drives the motor resulting in servomechanism operation that is well known to feedback control engineers. Each output shaft has an attached lever or pulley wheel or specially shaped structure to accomplish a given type of task (e.g. pulling or pushing or rolling or grabbing the tie) within the overall cycle. The motors are located on posts several feet high projecting up from a heavy baseplate approximately 1.5×3 feet in size that in turn is mounted upon a wooden base. The input to each of the 10 servomechanisms, which controls how far it is to rotate, is an analog voltage coming from a D/A converter controlled by a personal computer. The computer runs a program that sequentially reads out a data set line by line. The data in each line consists of a first number which selects which motor is to be operated, a second number which determines how far it is to rotate, and a third number which determines how long the computer is to wait before reading out the next line, e.g. typically the duration of the motor motion. In the current version of the data set that successfully ties and unties the necktie, there are approximately 550 lines. It takes approximately 6 minutes to sequentially read out all of these lines, and therefore to tie and untie the necktie.




The most difficult challenge in automatically tying the four-in-hand knot is to push the wider part of the tie (henceforth labeled RT—for right tie) through the space between the first and second wraps of the RT around the narrow part of the tie (henceforth called LT—for left tie). In my design this guidance of the mechanically manipulated RT is facilitated by pulling the RT through a 3 inch diameter horizontally oriented support tube about which rotates an outer rotating tube over which RT has been previously wrapped (the second wrap). The first wrap of RT around LT has previously been manipulated to be outside and behind both concentric tubes so that when the RT is pulled through the support tube, it is automatically located between the first and second wraps. This use of a tube to guide RT as described above dominates the design and operation of the machine. It is explained more thoroughly in Section IV Method of Operation and in the various parts of FIG.


12


. The rotary and support tubes can be raised and lowered a distance comparable to the length of the suspended RT. A horizontal tab is attached to the periphery of the rotating tube at its left end. When RT is engaged in the tab and the tube is rotated, RT can be wrapped around the tube by an amount controlled by the tube rotation. In summary, the support tube can be vertically moved to position the outer rotating tube at different heights and the RT ultimately gets pulled through the inner support tube. Hereinafter the term tube assembly is used to stand for the concentric rotary and support tubes.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1A

(front view);

FIG. 1B

(right end view); and

FIG. 1C

(top view) are schematic diagrams of the tube assembly that is used to form loops of the tie and guide the placement of the end of the tie through the appropriate loops.





FIG. 2

is a schematic illustration (left end view) of the vertical moving assembly and the attached tube assembly.





FIG. 3A

(front view) and

FIG. 3B

(top view) are schematic diagrams of the hooker assembly and its attached crank assembly.





FIG. 4A

(front view) and

FIG. 4B

(right end view) are schematic diagrams of the whirler assembly.





FIG. 5A

(front view) and

FIG. 5B

(right end view) are schematic diagrams of the finger assembly.





FIG. 6A

(front view) and

FIG. 6B

(top view) are schematic diagrams of the grabber assembly.





FIG. 7

is a schematic diagram (front view) of the breaker assembly.





FIG. 8A

(top view) and

FIG. 8B

(front view) are schematic diagrams of the tie support assembly.





FIG. 9

is an overall signal flow diagram of the electronic controls.





FIG. 10

is a schematic diagram of a single one of the 10 identical circuits that controls a motor.





FIG. 11A

is a front view of the overall layout which, for clarity, does not show the tube, vertical moving, whirler, and finger assemblies or the winch, monitor, and circuit boards.

FIG. 11B

, for clarity, does not show the grabber, breaker, hooker, or tie support assemblies.





FIGS. 12A-12S

are a series of schematic diagrams of the various stages of the formation of the tie knot. Some of the elements of some of the assemblies forming the knot are shown.











DETAILED DESCRIPTION OF THE INVENTION




I. Mechanisms:




(1) The tube assembly and vertically moving assembly—(

FIGS. 1A-1C

,

FIG. 2

)




The rotating tube


1


is approximately 3.5 inches in diameter, and 4 inches in length. It has a 2 inch long tab


2


attached to the periphery of its left end which is raised about ¼ inch above the surface. The tab


2


is secured at its left end, extends rightwards and is open at its right end. To the left of the tab


2


, a timing belt


3


is bonded to the periphery of the rotating tube


1


and flanges


17


are provided. This bonded belt acts as a timing belt pulley wheel and engages a moving timing belt


4


that causes the rotating tube to rotate about an inner concentric support tube


5


which acts as a bearing surface. The support tube in turn is attached by a connecting bracket


6


to a vertically moving assembly


7


that, via a cable


19


and top pulley


9


, is moved upwards by a winch drum and motor


10


, and downwards by gravity—as allowed by the winch unwinding. The timing belt


4


is driven by a motor


11


and attached timing belt pulley


18


mounted on the connecting bracket


6


. The vertically moving assembly


7


moves on a vertical post


8


fixed to a heavy baseplate


12


. An additional vertical guide rod


13


combined with a slotted bracket


14


attached to the vertically moving assembly


7


prevents yaw motions of the rotating tube


1


. Additionally, the inside


15


and outside


16


cylindrical surfaces of the support tube are lined with Teflon tape to reduce friction of the tie being pulled through the support tube, as well as friction between the rotating tube


1


and the support tube


5


. A special provision is made to insure that the turns of cable


19


on the winch drum


10


never overlap in order to insure vertical accuracy. This is accomplished by feeding cable


19


leading to winch drum


10


through a vertical hole in guide


20


which moves laterally (into and out of the paper in

FIG. 2

) on pin


20




a


as vertically moving assembly


7


is moved up and down. This lateral motion occurs because an additional cable


21


at a slight angle to the vertical is also fed through the vertical hole in guide


20






(2) The hooker assembly—(

FIGS. 3A-3B

)




The horizontally oriented hooker


21


is made of a coathanger wire which at its right end has 90 degree bend containing a 2 inch long section and another 90 degree bend of ¼ inch to form a modified “U” of disparate leg lengths suitable for hooking a slender object. Hooker wire


21


is attached to the shaft of a motor


22


which is mounted on a block


23


containing linear bearings


24


that allow it to translate horizontally along two guide rods


25


supported in a U shaped mounting block


32


that is attached to a vertical post


33


attached to the baseplate


12


. The motor is pushed and pulled horizontally by a linkage


26


attached to the pedal


27


of a bicycle crank with integral sprocket wheel


28


which in turn is rotated by a bicycle chain


29


which is driven by sprocket wheel


30


attached to electric motor


31


also mounted on post


33


. This means of producing a horizontal translation is the reverse of the usual reciprocating to rotary conversion of motion such as was done in a railroad steam engine and is used for aesthetic purposes. In reality a rack and pinion or a leadscrew arrangement would have been more efficient but less pleasing to the eye.




(3) The whirler assembly—(

FIGS. 4A-4B

)




Whirler


34


is a multiply bent plastic piece, of the shape shown in

FIG. 4

, which has 1 inch diameter rod


35


at its distal end to catch RT when it rapidly sweeps RT around the rotating tube


1


. Rod


35


needs to be roughened to increase the friction coefficient so that the RT does not slip off during the whirling motion. Forward projection


36


of the end of whirler


34


allows it to push the RT through the Vee (see

FIG. 12



c


) formed by the LT and RT hanging from the tie support assembly (see

FIG. 8



b


), and let it fall forward of rotary tube


1


. Whirler


34


is attached to the shaft of motor


37


mounted by bracket


39


to vertical post


38


secured to baseplate


12


.




(4) The finger assembly—(

FIGS. 5A-5B

)




Finger


40


consists of lever


41


and oblique projection


42


coming off it several inches from its extremity. Lever


41


is attached to the shaft of a first motor


43


held by a bracket


44


attached to a second motor


45


whose shaft


46


is clamped stationary to bracket


47


mounted on vertical post


38


. Shaft


46


is oriented horizontally and is perpendicular to the direction of translation of hooker wire


21


. Thus when motor


45


is powered, both motors


43


and


45


rotate in roll which alters the plane of motion of lever


40


. When motor


43


is powered, lever


40


rotates so that it moves towards the front or rear surface of the rotating tube


1


.




(5) The grabber assembly—(

FIGS. 6A-6B

)




The grabber contains lever


48


attached to motor


49


whose rotation changes the elevation angle of lever


48


. The extremity of lever


48


contains an anvil bracket


49




a


. Attached partway up lever


48


is a second electric motor


50


, with its axis parallel to that of motor


49


, which rotates bar


51


whose extremity has an attached grabber jaw fixture


52


that mates with and pushes against anvil


49




a


to form a clamp. Both clamping surfaces of


52


and


49




a


are lined with a high friction material


53


(e.g. urethane class ML6 high friction material, Meridian Laboratory, Middleton, Wis.) to facilitate clamping the LT or RT even if only a small portion is engaged. Elevation motor


49


is mounted on bracket


50




a


secured to baseplate


12


.




(6) The breaker assembly—(

FIG. 7

)




The breaker consists of sturdy lever


54


attached to timing belt pulley wheel


55


which rotates on shaft


56


mounted in vertical post


57


attached to baseplate


12


. Pulley wheel


55


is rotated by electric motor


58


via several timing belts


59


,


60


and pulleys


61


,


62


,


63


, arranged to provide a mechanical advantage. The distal end of lever


54


contains short rod


64


at right angles to lever


54


which engages the main loop of the completed tie, where the neck would normally be, when Lever


54


is rotated about shaft


56


. Electric motor


58


is mounted on vertical post


57


by bracket


65


. The shaft


66


upon which are mounted pulley wheels


61


and


63


is supported by a bearing block


67


which is contacted by two tension screws


68


. The tension screws


68


are mounted in a block


69


fastened to post


57


at a position such that the two belts


59


, and


60


can be tightened to the desired tension when the tension screws


68


are advanced against the bearing block


67


. Bearing block


67


is supported by a swinging bracket


70


that is hinged to vertical post


57


by a pin


71


.




(7) The tie support—(

FIGS. 8A-8B

)




Near the middle of its length, a portion of the tie


77


is secured to a horizontal support piece


72


attached to vertical post


38


. This portion


77


is clamped in place between horizontal support


72


and front bar


73


so that the RT and LT hang straight down. The supported ends of the RT and LT are laterally positioned and separated by means of bottom guides


74


and top guides


75


, to locate RT and LT relative to the whirler, finger and hooker assemblies. Hinge pin


76


allows front bar


73


to be swung away from horizontal support piece


72


when locking knob


76


is unscrewed. This provides for initially loading and removing the tie


77


before or after the tying cycle, and, if desired, for removing the tie


77


at any time during the cycle (if the machine is stopped) e.g. when the knot is complete so it can be put on someone without disrupting the tied knot. Top guides


75


are rounded to avoid damaging tie


77


in the vicinity of where it is clamped.




(8) The electronic circuitry—(

FIGS. 9-10

)




Data from personal computer


78


comes into interface board


79


via printer port cable


80


. Two digital numbers are transmitted: the motor number and how far that motor should rotate. The motor number is converted into a logic enable signal on one of 10 lines


81


, each leading to a different sample and hold (S/H) module


82


. The second digital number is converted by a digital to analog converter into an analog voltage command


83


that is connected to the analog input terminal


84


of all 10 of S/H's


82


. All of the S/H modules


82


ignore the analog input voltage


83


except for the one S/H module


82


that has been selected by the logic enable voltage


81


(that was determined by the first digital number). The output


85


of each S/H


82


is the command voltage


85


fed through a resister Rin into the input


85




a


of each separate power amplifier


86


whose output


92


in turn is connected to a different one of the 10 electric motors


87


(FIG.


10


). The output


93


from each electric motor shaft potentiometer


88


is fed back through a resister Rin to the input


85




a


of amplifier


86


that drives the motor attached to that potentiometer via a buffer amplifier


89


. Each power amplifier


86


has a feedback resistor Rf between its output


92


and its input


85




a


as is standard practice by electronic engineers so that at input


85




a


to each power amplifier


86


the potentiometer output is subtracted from S/H output


85


resulting in a feedback servomechanism in which a given voltage command corresponds to a given shaft angle—as is well known by feedback control engineers. To minimize extraneous voltages and grounding problems, the power return from the motors goes to a power ground,


102


, which is kept separate from the ground


94


for the low level voltage signals as is customary practice.




Thus as the different pairs of numbers are sequentially read out, different S/H modules


82


are controlled which in turn makes the corresponding motors move through shaft angles that correspond to the command voltages. The computer


78


runs a program which reads out the two numbers to the printer port and then, according to a third parameter in the data set of numbers, the computer waits a prescribed amount of time before reading out the next pair of numbers. Different data sets correspond to different sequences of moves of the various actuators described above so as to tie and untie the necktie. Thus the data set is what determines how the different parts move. The


10


S/H


82


modules,


10


power amplifiers


86


and feedback connections


93


and motor output connections


92


are contained on two separate circuit boards


90


,


91


. These and the interface board


79


are visibly mounted to a vertical post


100


secured to the baseplate


12


in a pleasing inverted Y configuration


101


.




(9) Overall Layout—(

FIGS. 11A-11B

)




Baseplate


12


is mounted on top of dull black plywood base


95


with 4 casters


96


and side shelf


97


for the computer keyboard and mouse. Computer


78


is located out of sight inside base


95


. Attached to the rear of base,


95


is vertical post


98


that supports color flat panel computer monitor


99


that continually displays the command data set as the different parts move using a separate color for each different motor. The relative placement of the different actuators described in


1


thru


8


above is shown in FIG.


11


.




II. Method of Operation—(FIGS.


12


-A-


12


S)




At the beginning of the cycle, both RT and LT hang straight down from tie support


72


,


73


, and rotary tube


1


is at the lower end of its travel—6 inches above the end of RT. The first part of the cycle uses finger


40


to manipulate the end of the RT so that it is caught in tab


2


, no matter how it might previously have been hanging (e.g. at startup) (

FIG. 12



a


). Rotary tube


1


is then raised until it is about ¾ of the way up to tie support


72


,


73


. Rotary tube


1


is also rotated part of a turn, and because RT is captured in tab 2, 6 inches above its end, the 6 inch free end of the RT hangs down from one side of tab


2


while on the other side of tab


2


RT is partially wrapped around rotary tube


1


creating a loop of RT hanging down from rotary tube


1


(

FIG. 12



b


). With the prior assistance of finger


40


, the LT is drawn through this loop of RT (

FIGS. 12



b,c


) by hooker


21


. The front of the loop is next moved to the rear of rotary tube


1


by finger


40


so that a very loose first wrap of RT around LT is created which is located outside of and behind rotary tube


1


(

FIG. 12



c


). This creates a Vee space between the RT and LT where they hang down from Tie Support


72


,


73


. By a series of back and forth rotations of rotary tube


1


, the slack of the first wrap is removed so that RT is wrapped tightly around LT (

FIG. 12



d


). This slack removal, which is crucial, results from the interaction of the friction characteristics of the tie and rotary tube


1


and its tab


2


with the weight of the hanging tie suspended from rotary tube


1


. When the tube


1


with tab


2


rotates in the forward direction it drags the tie with it, but when it rotates in the reverse direction there is slippage between the RT and rotary tube


1


which takes up the slack.




Next, using finger


40


, the free hanging end of RT is manipulated laterally along rotary tube


1


to a position centered under the Vee space (

FIG. 12



e


). Then the specially shaped whirler


34


,


35


rotates about its horizontal axis to intercept the hanging RT and carry it around rotary tube


1


and thru the Vee space (

FIGS. 12



f,g


). This is equivalent to manually bringing the RT up from under after the second crossover of the four-in-hand tie knot. It is the second wrap plus the end of RT hanging for 6 inches over the front of rotary tube


1


. RT is now manipulated to the right end of the rotary tube


1


and its support tube


5


by finger


40


(

FIG. 12



h


), and hooker


21


is moved through support tube


5


, rotated about its axis in order to intercept the length of RT about 6 inches from its end (

FIG. 12



i


), and, finally, hooker


21


pulls RT through support tube


5


(

FIG. 12



j


). At this point topologically speaking, the knot has been formed.




The next process is to scrape the second wrap off of the rotating tube


1


using finger


40


, and hooker


21


in a pushing rather than pulling mode (

FIG. 12



k


). Rotary tube


1


is then lowered out of the way and the loosely configured knot hangs free with the ends of the LT and RT protruding from the loops of the knot (FIG.


121


). The LT is then secured by hooker


21


in order to position the hanging end of the RT in a favorable location so that the RT can be grabbed by grabber jaws


49




a


,


52


and sequentially pulled in a series of moves to tighten the knot (

FIG. 12



m


). After each pull RT is released by grabber jaws


49




a


,


52


and repositioned so that the they can subsequently clamp RT closer to the knot and then RT is pulled again. After multiple pulls (e.g. four) the RT is then released and the LT is secured by grabber jaws


49




a


,


52


(

FIG. 12



n


) and pulled tight to shape the knot so that it looks as if it had been tied by a human (

FIG. 12



o


). The knot is then pulled apart by breaker lever


54


which is moved into the large loop where a persons neck would normally reside (

FIG. 12



p


), and this loop is pulled until the LT is pulled through the knot which as a result comes apart. To facilitate this, the RT is first secured by grabber jaws


49




a


,


52


(

FIG. 12



r


) with the aid of hooker


21


(

FIGS. 12



p,q,r


) and held at an oblique angle which reduces the friction of the LT being pulled through the knot (

FIG. 12



r


). The resulting twisted free hanging RT (

FIG. 12



s


), is then swung back and forth in a variety of ways by finger


40


to remove all twists and turns so it hangs straight and it is then manipulated by finger


40


so it is caught in tab


2


on rotating tube


1


, thus returning the tie to its original position (

FIG. 12



a


). All the motors return to their initial positions completing the cycle.



Claims
  • 1. A machine for automatically tying a four-in-hand necktie knot in a necktie, comprising:a necktie support platform for hanging a necktie, said necktie having a left hand short segment and a right hand long segment, a rotatable cylinder having a tab to temporarily hold the right hand long segment, wherein the rotatable cylinder is supported by a concentric smaller support tube that is moveable in an up and down vertical motion, a hooking mechanism capable of pulling the left hand short segment through a loop of the right hand long segment hanging from the rotatable cylinder, and of pulling the right hand long segment through the concentric support tube, a finger mechanism capable of laterally moving the right hand long segment along the length of the rotatable cylinder and then pushing the right hand long segment towards the rear of the rotatable cylinder, and a whirler mechanism capable of flipping an end of the right hand long segment around the rotatable cylinder and up through a space between the right hand long segment and the left hand short segment and the necktie support.
  • 2. A machine according to claim 1, further comprising an electronic and feedback control for operating various mechanisms in response to a sequence of voltage commands.
  • 3. A machine according to claim 1, further comprising a grabber mechanism for holding and pulling the right hand long segment or the left hand short segment.
  • 4. A machine according to claim 3, wherein the grabber mechanism comprises a clamping surface lined with a urethane high friction material.
  • 5. A machine according to claim 1, further comprising a breaker assembly for pulling apart a four-in-hand necktie knot.
  • 6. A machine for automatically tying a four-in-hand necktie knot in a necktie suspended from a platform, comprising:a necktie support platform, a necktie, vertically hung by a middle segment from the support platform, with a protruding left hand (LT) short segment and a right hand (RT) long segment, a horizontal rotatable cylinder supported by a concentric smaller support tube which is attached to means to provide vertical up and down motion, said rotatable cylinder provided with means to rotate it and means to temporarily attach RT to its periphery so that with coordinated vertical motion of the support tube and rotation of the rotatable cylinder RT can either be rolled up tightly around said cylinder or loosely draped around said cylinder leaving a loop of hanging RT, a horizontally oriented hooking mechanism capable of pulling LT through a loop of RT hanging from the rotatable cylinder, and also of pulling RT through the support tube after RT has been appropriately moved to the open end of the support tube, a finger mechanism capable of laterally moving RT along the front length of the rotatable cylinder and then pushing it either to the rear of the cylinder or positioning it even with the opening of the support tube, a whirler mechanism which flips the end of the suspended RT around the rotatable cylinder and up through a space between the RT and LT and the tie support so that it lies on the front surface of said cylinder, and a grabber mechanism for holding and pulling the RT, so as to pull the end of RT after the RT has been scraped off the rotatable cylinder so as to pull the nascent four-in-hand knot tight.
  • 7. A method for automatically tying a four-in-hand necktie knot in a necktie, comprising:hanging a necktie on a necktie support platform by a middle segment of the necktie so that a left hand short segment and a right hand long segment hang from the support platform, temporarily attaching the right hand long segment to a periphery of a horizontal rotatable cylinder; vertically moving and rotating the horizontal rotatable cylinder, thereby rolling the right hand long segment partially around the horizontal rotatable cylinder and creating a loop of the right hand long segment hanging from the horizontal rotatable cylinder; pulling the left hand short segment through the loop of the right hand long segment; laterally moving the front of the loop of the right hand long segment along the front length of the horizontal rotatable cylinder to its end and then to the rear of the horizontal rotatable cylinder, thereby creating a loose first wrap of the right hand long segment around the left hand short segment; rotating the horizontal rotatable cylinder back and forth, thereby removing the slack of the loose first wrap so that the right hand long segment is wrapped tightly around the left hand long segment; flipping a suspended end of the right hand long segment around the rotatable cylinder and up through a space between the right hand long segment and left hand short segment and the necktie support platform so that it lies on a front surface of the horizontal rotatable cylinder, moving the right hand long segment along the front of the cylinder to its end and then pushing the right hand long segment rearwards so it is even with the open end of the horizontal rotatable cylinder; pulling the right hand long segment through the horizontal rotatable cylinder; removing the right hand long segment off of the horizontal rotatable cylinder, thereby forming a nascent four-in-hand knot; and holding and pulling the right hand long segment, thereby tightening the nascent four-in-hand knot.
  • 8. A method for automatically tying a four-in-hand necktie knot according to claim 7, further comprising holding and pulling the left hand short segment, thereby shaping the four-in-hand knot.
  • 9. A method for automatically tying a four-in-hand necktie knot according to claim 7, further comprising pulling apart the four-in-hand necktie knot.
Parent Case Info

This application claims the benefit under 35 U.S.C. 119(e) of provisional application No. 60/364,925 filed Mar. 15, 2002, in the name of Seth R. Goldstein, the disclosure of which is incorporated by reference in its entirety.

US Referenced Citations (4)
Number Name Date Kind
5562456 Cianciotto Oct 1996 A
6015172 Williams et al. Jan 2000 A
6120068 DiPietro Sep 2000 A
6543819 Hakimain Apr 2003 B2
Provisional Applications (1)
Number Date Country
60/364925 Mar 2002 US