Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65B—MACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
  • B65B51/00—Devices for, or methods of, sealing or securing package folds or closures; Devices for gathering or twisting wrappers, or necks of bags
  • B65B51/04—Applying separate sealing or securing members, e.g. clips
  • B65B51/08—Applying binding material, e.g. to twisted bag necks

Definitions

• DEVICE FOR BAG TYER disclose automatic bag closing and tying machines used for closing a flexible bag by attaching and twisting a wire-like ribbon about the neck of the bag.
• Discrete lengths of ribbon are capable of being disengagedly formed into fasuy held twist ties by rotationally deforming terminal ends of said lengths about each other.
• the ribbons can comprise polymers, such as polyalkylene terephthalates, polyvinylchlorides, styrcne-acrylonitrile copolymers and polystyrenes.
• Optional polymeric materials include elastomeric impact modifiers and plasticizers.
• the patent states that the ribbon was utilized in an automatic bag closing and tying machine (model 50-7, Burford Corporation) at packaging rate of 60 bags per minute. The machine produced tight ties having between 1 and 11/2 twists.
• U. S. Patent No. 5,342,687 discloses a non-metallic coreless twist-tie formed by extruding polymeric material and men drawing the material at a rate of more than about 2.5 times.
• the polymer is described as being formed from polymeric resin having a degree of crystallization of about 10% to 60% at a crystallized temperature range of about 100 degree(s) C. to 250 degree(s) C. and can also include a quantity of fine glass beads.
• Non-metallic coreless twist-tie ribbon has a different cross-sectional profile and physical characteristics that may result is slippage of the ribbon in the twister hook, loose ties and some times disengagement of the end of the ribbon from the holder.
• the bag neck tying device disclosed herein incorporates a bag neck gathering mechanism comprising motor driven gathering belts for moving a bag neck along a path in a plane into engagement with a bag stop controlled by an electric brake positioned adjacent a ribbon holder- shear assembly which holds the free end of a ribbon of tie material.
• a motor driven needle wraps the strand of tie material around the gathered neck of the bag, and a motor driven twister hook assembly engages the free end and the running end of the ribbon adjacent the gathered neck for twisting the ribbon.
• Independently controlled bi-directional, brush type servomotors are mounted in the separate subassemblies of the tying device. Each of the servomotors is controlled by a solid state
• DC motor controller in a closed loop feedback system under the control of a multi-channel microcontroller which precisely starts, controls and stops each of the servomotors in a pre-assigned sequence for each cycle of the tying apparatus.
• An improved holder shear assembly incorporates a V-shaped groove formed in the holder and a V-shaped rib formed on a gripper finger such that the ribbon is contacted at several different areas before the ribbon is cut.
• the gripper finger As the gripper finger is rotated it pushes the ribbon into the corner of a holder cutting area. Tension on the ribbon extrudes the ribbon and grabs to pre-hold the ribboa As the gripper finger rotates further, the ribbon is molded and bent over a cutting edge on the holder. This causes the ribbon to be securely held between surfaces on ⁇ e gripper finger and the holder before the ribbon is cut.
• V-shaped groove in the holder and the V-shaped rib on the gripper finger are not parallel to each other. Consequently, increasing the tension on the ribbon increases the gripping action.
• a shuttle bar connected for moving the gripper finger is mounted in a resilient bushing such that different gauges of wire or wireless ribbon can be used with the holder shear assembly without requiring adjustment of cams and other actuating mechanisms.
• a ribbon guide is mounted adjacent the twister hook and positioned such that rotation of the twister hook draws tails of a severed section of ribbon across the guide surface so that it is positioned at an angle of approximately 90° relative to the twister hook allowing the twister hook to securely engage the tails of the ribbtin to prevent slippage between the ribbon and the twister hook.
• the ribbon is securely gripped by the twister hook the ribbon is twisted a predetermined number of twists between the twister hook and the neck of a bag encircled by the ribbon. This gripping action draws the ribbon material tight around the gathered neck of a bag.
• Figure 1 is a perspective view illustrating the front of the bag neck tying device
• Figure 2 is a diagrammatic front elevational view
• Figure 3 is a diagrammatic rear elevational view
• Figure 4 is an end view looking generally in the direction of the arrows along line 4-4 in Figure 2;
• Figure 5 is a diagrammatic end view illustrating the discharge end of the bag neck tying device, looking in the direction of the arrows along line 5-5 in Figure 2;
• Figure 7 is a wiring diagram of the closed loop microcomputer controlled control system
• Figure 8 is a graphic representation of the sequence of operation of the needle, hook and shear assemblies during a complete cycle of operation
• Figure 10 is a fragmentary perspective view of the twister hook assembly and the holder shear assembly
• Figure 11 is a diagrammatic perspective view of the holder shear assembly in an inverted position
• Figure 13 is a diagrammatic view illustrating a pinch angle between a gripper finger and holder. Numeral references are employed to designate like parts throughout the various Figures of the drawing.
• the wire tying device generally designated by the numeral 10, in FIGS. 1 and 2 of the drawing is preferably of the type disclosed in U.S. Patent No. 5,483,134, that issued January 9, 1996, to Frazier, et al, the disclosure of which is incorporated herein by reference for all purposes.
• twister hook assembly 50 and a holder-shear assembly 60 are incorporated into the device to provide improved performance when different types of ribbon or ribbon constructed of different materials are used to tie bags.
• the ribbon 15 may be constructed of wire enclosed in paper or plastic or it may comprise a ribbon of plastic or any other material.
• the strand of ribbon 15 extends around one or more pulleys 41, 41a and 41b, mounted on shafts 41a', from a spool 41 c of tie material.
• spool 41c The mounting for spool 41c is similar to that disclosed in U. S. Patent No. 3,919,829 entitled “APPARATUS FOR TYING PACKAGES AND WRAPPING MATERIALS", the disclosure of which is incorporated herein by reference in its entirety for all purposes.
• spool 41c of tie material is mounted on a shaft and the ribbon 15 is fed from spool 14c, routed around rollers 4 lb, 4 la and 41, around needle roller 44 and the end of the ribbon
• Spool 41c is mounted on a shaft engaged by a brake (not shown).
• a brake (not shown).
• needle 42 forms a loop of tie material around the gathered neck of a bag
• the force of inertia and force exerted by the brake cause the spool 4 lc to remain stationary momentarily as a crank arm, on which roller 41a is mounted, is rotated.
• one of the pulleys 41, 41a or 41b is preferably equipped im a sensor device which is capable of calculating the amount of ribbon 15 dispensed from spool 41c.
• the sensor apparatus determines whether or not a bag neck is present As needle 41 moves from the full outline position illustrated in Figure 2 to the dashed outline position, if a bag neck is not positioned in the path of the ribbon, the cycle of operation will be interrupted so that the holder-shear assembly 60 will not be actuated and die twister hook assembly 50 will not rotate. This prevents actuation of the holder-shear assembly which would have resulted in the ribbon being dropped or released if a bag neck was not present
• the frame of the bag tying device may assume many configurations.
• upper and lower face plates 16 and 17 are supported on forward edges of vertically extending end plates 18 and 19 having slots formed therein to permit passage of a bag neck.
• a horizontal mounting plate 19a extends between lower portions of end plates 18 and 19 and a vertical mounting plate 16a extends outwardly from end plate 18.
• bag neck gathering apparatus 20 comprises, in a preferred embodiment of the invention, an upper gathering belt 22 routed around a driven pulley 24 and idler pulleys 26, 27 and 28.
• the bag neck gathering mechanism 20 further comprises a lower gathering belt 32 routed around a driven pulley 34 and idler pulleys 36, 37 and 38.
• the portion 29 of the upper gathering belt 22, extending between idler pulleys 27 and 28, is substantially parallel and closely spaced relative to the portion
• driven shaft 25 having driven pulley 24 mounted on one end, has a pulley 23 mounted on its opposite end.
• a pulley 30 mounted on die drive shaft of motor Ml drives pulleys 23 and 33 dirough a belt 31 such that driven pulley 24 rotates in a clockwise direction while driven pulley 34 rotates in a counterclockwise direction, as viewed in Figure 2 of d e drawing.
• Belt guards 16a and 16b and 17a preferably extend between the gatiiering belts and products on die conveyor.
• the bag neck is moved into a slot in the belt guard by brushes (not shown) and d e product in the bag engages the belt guards when the neck of the bag is drawn by gathering belts 22 and 32 around a bag stop lever 80. It should be appreciated diat other and further gathering structures may be used to form a garnered neck on a bag.
• motor Ml is driven by a solid state DC motor controller 91 which is capable of varying the speed of motor Ml to substantially synchronize movement of upper gathering belt 22 and lowering gathering belt 33 with the speed of a conveyor 300 moving packages 125 adjacent me bag gathering mechanism 20.
• the conveyer 300 would preferably bring bags to and dirough the tier at a speed of approximately 300 feet per minute and d e gathering belts 22 and 32 would preferably be driven at a speed of, for example 305 feet per minute, so that the neck of the bag would be accelerated for gathering die neck, stopped momentarily while it is being tied with a ribbon and then discharged in a substantially continuous operation.
• die garnering assembly 20 also includes a bag stop lever 80, illustrated in Figures 2 and 3, mounted on shaft 85 for rotary movement about a horizontal axis, in the illustrated embodiment.
• Shaft 85 extends dirough an electric brake 82, which momentarily locks lever 80 in a lowered position extending across patii 12 such that gathering belts 22 and 32 move me bag neck into engagement with lever 80.
• the electric brake 82 is released and d e gathered neck, carried between belts 22 and 32, urges die lever 80 upwardly such that it does not obstruct movement of the gathered neck.
• die lever 80 moves back to the illustrated position extending across path 12.
• a needle assembly 40 is positioned for wrapping a strand 15 of ribbon material around a gathered neck of a bag.
• the needle assembly 40 comprises a needle 42 carrying idler rollers 44, 44a and 44b.
• the needle 42 is mounted on die output shaft 45 of a gear box 46 driven by motor M2.
• Needle 42 is shown in its home position in Figures 1 and 2 of die drawing. Motor M2 moves needle 42 from d e full oudine position to die dashed oudine position, illustrated in Figure 2 of the drawing, and tiien reverses for moving the needle 42 back to die position illustrated in full oudine in Figure 2.
• a twister hook assembly 50 comprises a twister shaft 52 rotatably mounted in a bearing 53 having a hook 54 on one end thereof and a pulley 55 on die odier end.
• a drive pulley 56 is mounted on die drive shaft of motor M3 and drives pulley 55 dirough a belt 58.
• a ribbon guide plate 58 is mounted on die upper end of a support plate 57 secured to bearing block 53 and extending generally parallel to shaft 52.
• the ribbon guide plate 58 has an opening which encircles shaft 52 to provide an upper surface extending generally transversely of twister hook 54.
• Tails of ribbon 15 extend upwardly from holder shear assembly 66 and are engaged by hook 54 when shaft 52 is rotated
• the tails of the severed section of ribbon are drawn across guide surface 58 and deflected relative to twister hook 54 at an angle of approximately 90 ° . This reduces the tendency of the tails of die severed ribbon to slip relative to die twister hook.
• die loop portion of ribbon 15 extends above hook 54 mounted on shaft 52.
• Ribbon guide plate 58 mounted immediately below twister hook 54 pulls the tails 15a and 15b across the upper surface of ribbon guide 58 which forms a "kink" where hook 54 engages tails 15a and 15b to at least partially wrap the ribbon around die surface of hook 54 and pull it into a groove between hook portion 54 and shaft 52.
• Rotation of shaft 52 and hook 54 causes die ribbon material above hook 54 to be twisted
• ribbon guide plate 58 is positioned between twister hook 54 and die holder shear assembly 60.
• a ribbon holder-shear assembly comprises a holder and shear assembly of die type disclosed in U. S. Design Patent No. 307,281 to Charles E. Burford and U. S. Patent No. 4,856,258 entided WIRE TYING DEVICE, which issued August 15, 1989, to Charles E. Burford and Jimmy R. Frazier.
• the holder-shear assembly 60 comprises a gripper arm 62 having a gripper finger 64 on one end diereof rotatably secured to a mounting plate 66 by bolt 65.
• a pair of anvils 68 and 69 are formed on the end of mounting plate 66, each being associated with shear surfaces 68a and 69a to grip and cut a strand of ribbon as will be hereinafter more fully explained
• the gripper finger 64 As the gripper finger 64 is rotated it pushes die ribbon into die corner 69d between the inclined surfaces 69c and 69e which form a holding area. Because d e ribbon is under tension, this "V" point extrudes die ribbon and grabs to pre-hold die ribbon. As die gripper finger rotates further, die ribbon is molded around point 69b and bent over the cutting edge 69a of anvil 69.
• the gripper finger has ribs 64a and 64b having surfaces that are angularly disposed at die same angle as surfaces 69c and 69d on anvil 69. However, d e edge of the rib 64a and the inner section 69d between surfaces 69c and 69e are not parallel. As illustrated in Figure 13, the surface of die rib forms a tapered slot 67 of diverging cross-section to make a pinch angle. As the ribbon 15 is pulled out of the cutting area, this causes the ribbon to be pinched tighter as tension increases.
• Gripper finger 62 is oscillated between anvils 68 and 69 by a shuttie rod 75 having a cylindrical end 75a wi ⁇ a resilient bushing 75b through which a bolt 75c extends.
• the device operates effectively with wire or wireless ribbon 15 and also different gauges of wire or wireless ribbon because resilient bushing 75b is compressed and deforms to accommodate different size ribbon in slot 67.
• Profile of cam 75 is shaped to permit rotation of die cam through an angle of a few degrees when die cam and shuttle bar are in home positions without changing the cam follower position.
• a cam 70 is mounted on die shaft of motor M4 and is configured to engage cam-followers 72 and 74 on spaced arms 71 and 73 secured to a shutderod 75 mounted for reciprocating movement in bearings 76.
• a link 75a secures the end of gripper arm 62 to shuttle rod 75.
• cam 70 will exert force through cam-followers 72 and 74 for moving shuttie rod 75 for pivoting the actuating arm 62 about bolt 65.
• the free end of me ribbon is gripped between the end of gripper finger 64 and anvil 68 or 69, depending on which direction d e gripper finger 64 is shifted.
• needle 42 wraps die intermediate section of d e ribbon 15 around die gadiered neck of a bag, the ribbon will be positioned between gripper finger 64 and die odier anvil 68 or 69.
• gripper finger 64 is shifted to its opposite position, d e ribbon will be cut and die free end of die strand of ribbon will be gripped between gripper finger 64 and anvil 68 or 69.
• roller 41 has a plurality of index points 4 lx.
• die index points are formed by steel dowel pins circumferentially spaced around d e axis about which roller 41 rotates.
• a proximity switch is positioned near index pointers 41x for making an electrical circuit when die presence of an indexing pin 4 lx is sensed.
• the proximity switch is of conventional design and is connected dirough a suitable power supply and amplifier to d e CPU 96.
• the CPU monitors die proximity output and counts die pulses produced by index pins 4 lx in roller 41.
• the CPU 96 calculates die amount of ribbon dispensed to determine whedier or not a bag neck is present as needle 42 moves from die full oudine position illustrated in Figure 2 of die drawing toward die dashed oudine position illustrated in Figure 2 of die drawing.
• die CPU will terminate a portion of die remainder of die cycle of operation so diat holder-shear 65 will not be actuated to prevent releasing die end of ribbon 15 which is gripped between gripper finger 64 and anvil 68 or 69.
• a switch 86 is actuated by switch arm 88, which actuates a timer for energizing electric brake 82 which momentarily locks bag stop 80 in a fixed position for a predetermined period of time, for example 0.25 seconds for restraining the leading edge of a bag neck, such that gathering belts 22 and 32 will gather the neck adjacent bag stop 80.
• electric brake 82 At the expiration of die predetermined period of time, electric brake 82 will be de-energized so diat linear movement of the bag neck will rotate bag stop 80 upwardly to release the bag so diat it will be moved away by the conveyor.
• Bag stop 80 is biased toward the position illustrated in Figure 3 of the drawing by a spring 83. It should be readily apparent that the spring 83 may be replaced by a counter-weight, air cylinder or other suitable biasing mechanism to resiliendy urge bag stop 80 toward its home position.
• Motors Ml, M2, M3 and M4 are bi-directional, permanent magnet, DC brush-type servomotors having outputs proportional to die voltage applied across the armatures. Such motors are commercially available from Groschopp, Inc. of Sioux Center, Iowa as a "Power Master 8304"
• diat odier motors and motors of other sizes may be provided to facditate driving die various assemblies. For example, it is contemplated diat smaller motors would be used in a counter top model used for gathering and fastening materials such as cods of electrical cord water hose, tubing, or yarn, and bundles of cable, rods, or carrots and odier produce.
• One side of die armature winding of each motor Ml, M2, M3 and M4 is connected to ground such diat reversing the polarity of current dirough die armature winding reverses die direction of rotation of die motor.
• die numeral 90 generally designates a power supply for delivering electric current to motor controller 91 and to motor Ml in the bag neck garnering mechanism 20; motor controller 92 and motor M2 in the needle assembly 40; motor controller 93 and motor M3 in the twister assembly 50; and motor controller 94 and motor M4 in the holder- shear assembly 60.
• a suitable 32-bit integrated microcontroller 96 is the MC68332 which is commercially available from Motorola, Inc. of Schaumburg, Illinois as a product referred to as "MC68332 SIM" System Integrated Module.
• the MC68332 microcontroller 96 contains intelligent peripheral modules such as the time processor unit (TPU) which provides 16 microcoded channels for performing time-related activities for simple input capture or output capture to complicated motor control or pulse widdi modulation.
• High-speed serial communications are provided by die queued serial module (QSM) widi synchronous and asynchronous protocols available.
• QSM die queued serial module
• Two kilobytes of fully static standby RAM allow fast two-cycle access for system and data stacks and variable storage widi provision for battery backup. Twelve chip selects enhance system integration for fast external memory or peripheral access.
• These modules are connected on-chip via an intermodule bus (1MB).
• the CPU board is connected to an auxiliary board 98 dirough a connector header which carries data signals and address signals.
• Driver circuits C1-C4 which generate pulse width modulated (PWM) signals, are mounted on the auxiliary board along widi die decoders D1-D4.
• the pulse widdi modulated signals from driver circuits C 1-C4 are sent to the motor drivers 91-94 selectively delivering positive or negative DC power to control the operation of motors M1-M4.
• the circuits carrying input signals from the encoders E1-E4 to decoders D 1-D4; die circuit carrying pulse widdi modulated signals from driver circuits C1-C4 to motor drivers 91-94; and the circuits carrying power from the motor drivers 91-94 to motors M1-M4 form a closed loop control system.
• the closed loop control system depends upon die feedback concept for operation and die output PWM signals are forced to a pre-assigned function of the reference input of the microcontroller of die central processing unit
• the microcontroller 96 sends control PWM signals determined by die programmed movements stored in RAM memory in a pre-assigned order as a function of time after switch arm 88 returns to its home position illustrated in Figure 3.
• the control PWM signals are delivered to die control circuit
• Each encoder E1-E4 connected to the shaft of motors M1-M4, send quadrature signals to the decoders D1-D4 that indicate die position of the shaft of each motor.
• the confrol PWM signals delivered to each control circuit C1-C4 arc delivered to motor drivers 91-94.
• the quadrature signals from decoders D1-D4 are read to adjust die control PWM signals.
• Drivers 92, 93 and 94 which control the delivery of power to motors M2, M3 and M4, respectively, for controlling the needle assembly 40, twister hook assembly 50 and holder-shear mechanism 60 are substantially identical.
• One side of die winding of each of die motors M2, M3 and M4 is connected to ground
• Drivers 92, 93 and 94 deliver eidier positive or negative power to die other side of die motor winding for driving motors M2, M3 and M4 in opposite directions. For example, when positive 34 volt direct current is delivered to die winding of motor M2, its shaft is driven in a clockwise direction. If negative 34 volt direct current is delivered to die winding of motor M2, its shaft will be driven in a counter-clockwise direction.
• the driver 91 for motor Ml connected to the bag gadiering assembly 20, is similar to drivers 92, 93 and 94 except that driver 91 is not provided widi die capabdity of delivering negative direct current because it is not necessary for motor M 1 to be driven in reverse.
• FIG 11 is a graphic representation of the sequence of operation of die needle, hook and shear assemblies during a complete cycle of operation.
• the microcontroller 96 is initially programmed by a computer through a serial port RS for storing a program which will initiate movement of needle 42 from its home position illustrated in Figure 3 and die speed of movement toward die dashed oudine position illustrated in Figure 3 controlled by signals delivered dirough control circuit C2 to motor M2.
• switch arm 88 will be moved downwardly from the position illustrated in Figure 3 which will energize electric brake 82 so that belts 22 and 32 will move die neck of the bag into engagement with bag stop 80 causing die neck to be gatiiered
• switch arm 88 will move back to the position illustrated in Figure 3 causing switch 86 to send a signal to the microcontroller for starting a new tying cycle.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Package Closures (AREA)
• Control Of El Displays (AREA)
• Basic Packing Technique (AREA)

Applications Claiming Priority (3)

Publications (3)

Family

ID=22022277

Family Applications (1)

Country Status (8)

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Family Cites Families (13)

• 1998
  • 1998-09-17 CA CA002272879A patent/CA2272879C/fr not_active Expired - Lifetime
  • 1998-09-17 EP EP98967063A patent/EP1003673B1/fr not_active Expired - Lifetime
  • 1998-09-17 ES ES98967063T patent/ES2213936T3/es not_active Expired - Lifetime
  • 1998-09-17 AU AU32849/99A patent/AU3284999A/en not_active Abandoned
  • 1998-09-17 WO PCT/US1998/019392 patent/WO1999025615A1/fr not_active Ceased
  • 1998-09-17 JP JP51831699A patent/JP4275745B2/ja not_active Expired - Lifetime
  • 1998-09-17 DE DE69821770T patent/DE69821770D1/de not_active Expired - Lifetime
  • 1998-09-17 AT AT98967063T patent/ATE259740T1/de not_active IP Right Cessation

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