US 4,506,488 A · Wrapping machine and method

Abstract

A horizontal wrapping machine which includes a former for shaping a continuous film of packaging material drawn past the former into a continuous tube, a film drive for drawing the continuous film of packaging material past the former and past a cutting and sealing station, a product infeed drive for feeding products to be packaged through the former into the continuous tube of packaging material so that the products are spaced apart from one another in the tube, and a pair of motor-driven cut-heads at the cutting and sealing station for cutting and sealing the continuous tube of packaging material as each product moves past the cutting and sealing station. The horizontal wrapping machine further includes independent closed loop servo control circuits for the film drive, product infeed drive, and cut-head drive, each of which are responsive to a desired velocity control signal. The wrapping machine includes a first encoder on the shaft of a roller driven by the moving film, a second encoder coupled to the product infeed drive, and a resolver coupled to the cut-head drive. A microprocessor-based controller is coupled to the encoders, the resolver, and the servo loops for the infeed, film feed, and cut-head drives.

Claims30

Dependent claims

A method of wrapping products in packages formed from a continuous film of packaging material with each package containing a cut length of film, comprising the steps of:

shaping a continuous film of packaging material with a former by drawing the film past the former into the shape of a continuous tube;
drawing the continuous film of packaging material past the former and past a cutting and sealing station, at which the tube of packaging material is cut and sealed at cut points nominally coincident with the ends of the cut lengths, at a velocity dependent upon a film velocity control signal;
feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon a product infeed rate control signal;
producing the film velocity control signal and the product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former for each cut length of film drawn past the former;
determining the relative orientation between each product and its associated cut length of film moving past the film former;
determining if the relative orientation between a product and its associated cut length of film is such that the product is closer than a selected allowable distance to a cut point;
adjusting the location of a cut point if a product lies closer to the cut point than said allowable distance;
and
cutting and sealing the continuous tube of packaging material at each cut point, as adjusted if necessary, as each product moves past the cutting and sealing station.

6 more elements

A horizontal wrapping machine for wrapping products in packages formed from a continuous film of packaging material wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means, responsive to a film velocity control signal, for drawing the continuous film of packaging material past the former and past a cutting and sealing station at a velocity dependent upon the film velocity control signal;
product infeed means, responsive to a product infeed rate control signal, for feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon the product infeed rate control signal;
means for cutting and sealing the continuous tube of packaging material as each product moves past the cutting and sealing station;
means, coupled to the film drive means and the product infeed means, for producing said film velocity control signal and said product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former by the product infeed means for each cut length of film drawn past the former by the film drive means;
and
means for determining the relative orientation between each product and its associated cut length of film moving past the film former.

4 more elements

A horizontal wrapping machine for wrapping products in packages formed from rolls of a continuous film of packaging material wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means, responsive to a film velocity control signal, for drawing the continuous film of packaging material past the former and past a cutting and sealing station at a velocity dependent upon the film velocity control signal;
product infeed means, responsive to a product infeed rate control signal, for feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon the product infeed rate control signal;
means for cutting and sealing the continuous tube of packaging material as each product moves past the cutting and sealing station;
means, coupled to the film drive means and the product infeed means, for producing said film velocity control signal and said product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former by the product infeed means for each cut length of film drawn past the former by the film drive means;
a film splicer located upstream from the former for splicing the trailing end of a used roll of said continuous film to the leading end of a new roll of said continuous film and for producing a splice signal when said splice is made;
means for storing in a queue the cut lengths of film to be drawn past the former;
and
means, coupled to said splice signal and to said cut length storage means, for determining the cut length in said queue of cut lengths containing the splice and for producing a reject package signal for the package produced from said cut length containing said splice.

6 more elements

A horizontal wrapping machine for wrapping products in packages formed for a continuous film of packaging material wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means, responsive to a film velocity control signal, for drawing the continuous film of packaging material past the former and past a cutting and sealing station at a velocity dependent upon the film velocity control signal;
product infeed means, responsive to a product infeed rate control signal, for feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon the product infeed rate control signal;
means for cutting and sealing the continuous tube of packaging material as each product moves past the cutting and sealing station;
means, coupled to the film drive means and the product infeed means, for producing said film velocity control signal and said product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former by the product infeed means for each cut length of film drawn past the former by the film drive means;
film position sensing means upstream from the former for producing a film position signal for each cut length of film passing the sensing means;
film travel monitoring means for producing at an output a signal indicative of film travel;
means, coupled to the film position sensing means and to the film travel monitoring means, for accumulating a film travel value after each film position signal is produced by the film position sensing means based upon the output of the film travel monitoring means;
and
means for storing each film travel value accumulated by said accumulating means as a cut length in a cut length queue as each film position signal is produced.

7 more elements

A horizontal wrapping machine for wrapping products in packages formed from a continuous film of packaging material wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means, responsive to a film velocity control signal, for drawing the continuous film of packaging material past the former and past a cutting and sealing station at a velocity dependent upon the film velocity control signal;
product infeed means, responsive to a product infeed rate control signal, for feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon the product infeed rate control signal;
means for cutting and sealing the continuous tube of packaging material, as each product moves past the cutting and sealing station, including at least one heated cut-head;
means, coupled to the film drive means and the product infeed means, for producing said film velocity control signal and said product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former by the product infeed means for each cut length of film drawn past the former by the film drive means;
means for heating said cut-head in response to a heater activation signal;
means for measuring the temperature of said cut-head and for producing a cut-head temperature signal indicative of said measured temperature at an output;
and
control means coupled to said cut-head temperature signal output and to said heating means, for producing said heater activation signal when the measured cut-head temperature indicated by;
said cut-head temperature signal falls below a preset proportion of a setpoint cut-head temperature.

7 more elements

A horizontal wrapping machine for wrapping products in packages formed from a continuous film of packaging material wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means, responsive to a film velocity control signal, including at least one pair of finwheels, at least one of which is heated, for drawing the continuous film of packaging material past the former and past a cutting and sealing station at a velocity dependent upon the film velocity control signal;
product infeed means, responsive to a product infeed rate control signal, for feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon the product infeed rate control signal;
means for cutting and sealing the continuous tube of packaging material as each product moves past the cutting and sealing station;
means, coupled to the film drive means and the product infeed means, for producing said film velocity control signal and said product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former by the product infeed means for each cut length of film drawn past the former by the film drive means;
means for heating said finwheel in response to a heater activation signal;
means for measuring the temperature of said finwheel and for producing a finwheel temperature signal indicative of said measured temperature at an output;
and
control means coupled to said finwheel temperature signal output, and to said heating means, for producing said heater activation signal when the measured finwheel temperature indicated by said finwheel temperature signal falls below a preset proportion of a setpoint finwheel temperature.

6 more elements

A horizontal wrapping machine for wrapping products in packages formed from a continuous film of packaging material, notionally divided into a succession of cut lengths of film, wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means for drawing the continuous film of packaging material past the former and past a cutting and sealing station;
a product infeed conveyor positioned upstream of the former for feeding products to be packaged into the former and the continuous tube of packaging material;
product infeed drive means, responsive to a product infeed velocity control signal, for driving the product infeed conveyor at a velocity dependent upon the product infeed velocity control signal;
a pair of opposed cut-heads at a cutting and sealing station downstream from the former operable to be driven in unison to cut and seal the continuous tube of packaging material as each product moves past the cutting and sealing station;
cut-head drive means for driving the cut-heads to cut and seal the continuous tube of packaging material as each product moves past the cutting and sealing station;
film travel monitoring means for producing at an output a signal indicative of film travel;
product infeed monitoring means for producing at an output a signal indicative of product infeed conveyor travel;
means, coupled to the film travel monitoring means and to the product infeed conveyor drive means, for calculating the film velocity and deriving therefrom the product infeed velocity control signal and for outputting said signal to the product infeed drive means, the derived infeed control signal being such that the product infeed conveyor is driven to feed a product into the former for each cut length of film drawn past the former by the film drive means;
a product position sensor at the product infeed conveyor for producing a product position signal as each product passes the sensor;
a film position sensor adjacent the film upstream from the former for producing a film position signal for each cut length of film passing the sensor;
product/former position indicating means, coupled to the product position sensor and to the product infeed monitoring means, for producing a product position indication when a product is at the former;
and
means, coupled to the film position sensor and to the film travel monitoring means, and responsive to the product position indication of the product/former position indicating means, for determining the relative orientation between a product and its associated cut length of film at the former.

11 more elements

A horizontal wrapping machine for wrapping products in packages formed from a continuous film of packaging material wherein each package contains a cut length of film, comprising:

a former for shaping a continuous film of packaging material drawn past the former into a continuous tube;
film drive means, responsive to a film velocity control signal, for drawing the continuous film of packaging material past the former and past a cutting and sealing station at a velocity dependent upon the film velocity control signal;
product infeed means, responsive to a product infeed rate control signal, for feeding products to be packaged into the former and the continuous tube of packaging material at a rate dependent upon the product infeed rate control signal;
means for cutting and sealing the continuous tube of packaging material as each product moves past the cutting and sealing station;
means, coupled to the film drive means and the product infeed means, for producing said film velocity control signal and said product infeed rate control signal to maintain the film velocity and the product infeed rate such that a product is fed into the former by the product infeed means for each cut length of film drawn past the former by the film drive means;
means for determining the actual relative orientation between each product and its associated cut length of film moving past the film former;
means for storing a desired orientation between a product and its associated cut length of film;
and
means for comparing said desired orientation with each actual orientation between each product and its associated cut length of film moving past the film former.

6 more elements

Dependencies are inferred from the claim text.

Wrapping machine and method

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Wrapping machine and method

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Abstract

Claims30