Apparatus for precisely controlling the feeding of viscous and non-viscous liquid products into a packaging machine

• US 5,707,212 A
• Filed: 05/12/1995
• Issued: 01/13/1998
• Est. Priority Date: 05/12/1995
• Status: Expired due to Fees

• Current Assignee: Ernest L. Matthews
• Original Assignee: Ernest L. Matthews
• Inventors: Matthews, Ernest L.
• Primary Examiner(s): Thorpe, Timothy
• Assistant Examiner(s): THAI, XUAN MARIAN
• Application Number:
  US08/441,041
• Time in Patent Office: 977 Days
• Field of Search: 417/44.1, 417/53, 417/415, 417/539
• US Class Current: 417/44.1
• CPC Class Codes: B65B 3/32 by pistons co-operating with measuring chambers
• CPC Class Codes: F04B 13/00 Pumps specially modified to deliver fixed or variable measured quantities

Abstract

Precise control of the vertical motion of a piston or series of pistons within a cylindrical housing of a positive displacement pumping device to precisely set the discharge volume of viscous and non-viscous liquid products from the pistons. Uses a linear ball bearing screw actuated by an electronically-controlled servo motor. An electronic pulse generator incorporated in the servo motor provides pulses which are counted and used to set the maximum range of movement of the pistons.

Claims

1. Apparatus for precisely controlling the feeding of viscous and non-viscous fluid products into a packaging machine comprising in combination:

a. fluid intake means connected to a reservoir of fluid to be feed into a packaging machine;

b. fluid discharge means connected to a packaging machine to supply fluid thereto;

c. positive displacement pump means for drawing fluid through said fluid intake means and urging fluid through said discharge means, comprising a plurality of cylinders in parallel alignment each having an axial port, a piston mounted in each cylinder of said plurality cylinders for concomitant reciprocal movement therewithin, a reversible motor having an output shaft with an elongated worm coupled to said output shaft for concomitant rotation therewith and a carriage coupled to said worm for linear motion along the length thereof responsive to rotation of said worm by said motor, said carriage coupled to said pistons for urging said pistons linearly within each said cylinder a fixed linear increment per incremental rotation of said reversible motor;

d. rotary valve means interposed between said pump means and said intake and discharge means to selectively connect said pump means and said intake and discharge means; and

,

e. electronic means for iterative control of the displacement of said pump means, including a pulse generator coupled to said output shaft to generate a predetermined number of pulses per revolution of said shaft and programmable means for determining the movement of said carriage along said worm operably connected to said pulse generator to detect an output therefrom, and operably connected said motor to control the rotation thereof in response to said sensed rotation wherein said motor is a servo motor having a predetermined number of pulses per revolution of said output shaft and wherein said programmable means is programmed to correlate the number of pulses generated with the number of pulses required to move said servo motor through a predetermined angular measure and said angular measure with the linear movement of said carriage.

2. Apparatus as defined in claim 1 wherein said carriage comprises a ball bearing nut coupled to said worm such that ball bearings are urged along helical raceways on said worm to impart linear motion to said nut, at least one piston beam extending radially from said nut, guide means affixed to said piston beam distal said nut for maintaining said piston beam in radial alignment with said nut, said piston beam affixed to said piston.