Fairbanks, Inc.

Colt Industries Operating Corporation

Fairbanks Scales Inc.

Alec T Douglas

Harry J Keen

James S Havers

Frank J Rusk

Walter W Sevigny

A pressure transducer module includes a plurality of cavities, each cavity in fluid communication with a hydraulic load cell. Each cavity deforms with variations in the pressure of the hydraulic fluid in the cavity. Sensors generate output signals representative of the deformation of the cavities. The sensor output signals are digitized and multiplexed, whereby the transducer module generates a digital output data stream. The pressure transducer module is pre-calibrated for creep, hysteresis, non-linearity and temperature related errors. A computer controller stores the calibration data for the module. The pressure transducer module also includes a temperature sensor. A weighing system includes a weighing platform or structure; at least one pressure transducer module; and hydraulic transducers for measuring the load applied to the weighing platform or structure. A controller receives the outputs of the sensors and applies the calibration data to calculate the weight of the load on the platform. The transducer module may be used in weighing systems having different load ranges. Also provided is a method and apparatus for pre-calibrating the pressure transducer module, a method and apparatus for pre-calibrating the hydraulic transducers, and a method of performing cornering correction in a weighing system. In an alternative embodiment, the pressure transducer module may include a microprocessor and calibration data memory so as to perform error compensation on the pressure transducer module within the module itself.

Digitally compensated hydraulic scale system

A modular checkweigher/grader system is disclosed. A feed conveyor is provided for directing items to be weighed to a weighing conveyor. The entire system is modularly designed using lightweight durable materials, such as plastics and stainless steel. Each conveyor includes a conveyor belt in contact with upper and lower surfaces of a platform. The belts are tightened and loosened with quick release tension clamps and driven by air powered motors. The feed conveyor is attached to a frame by toggle clamps. The weighing conveyor is attached to a load cell which is connected to the frame by toggle clamps. These toggle clamps permit the entire feed and weighing conveyors to be easily removed. All of the air and electrical connector to the conveyors are by quick release connectors. The entire weighing conveyor is used as the weighing platform. A tachometer may be used to regulate the conveyor speed. A modular grading conveyor is disclosed for categorizing objects from the weighing conveyor. A tensioner is provided for allowing the grader belt to be slackened for easy cleaning. Grader paddle control modules are hinged for easy cleaning. The hinges are secured by butterfly nuts for easy removal of broken modules. All air and electrical connections to the paddle control modules are by quick release connectors.

Modular checkweigher and grading system

A load indicator conversion system is disclosed for converting a scale having a mechanical measuring system, such as a conventional portable beam scale, into a scale having an electronic measuring system for providing an electronic display, such as an LCD display, corresponding to the load applied to the mechanical load receiver of the scale, such as the scale platform [104], which is mechanically linked via the beam load rod assembly [110] and an s-hook arrangement [150] to a load cell transducer [1]. A single common temperature sensor is employed adjacent the load cell and the associated electronics to provide information on the variations in temperature to the microprocessor for enabling temperature compensation to take place. The mechanical linkable between the transducer and the existing mechanical load receiving member is accomplished by removing the balance beam [106] and connecting the load cell [1] to the beam load rod [110] which normally mechanically transfers the applied load from the scale platform to [104] the balance beam [106 ].

Mechanical scale conversion system

A postal type scale (20), such as an electronic scale, capable of weighing a plurality of different size packages (24, 34) comprises a weighing mechanism (26), a platform (22) for supporting a package (24, 34) thereon in a weighing relationship, and a movable weight display (30, 36) slidably mounted to the platform (22) and longitudinally extendable therefrom along a horizontal mounting surface (38) when the platform (22) is supported on the horizontal mounting surface (38). The weight display (30, 36) comprises a horizontal weight display (30, 30b), such as an LCD display (30b), which may be removably mounted to the horizontally movable display mounting member (36) for providing the display (30) at a position remote from the mounting member (36). The weight display (30, 36) is variably extendable beyond the platform edge (32) along the horizontal mounting surface (38) from a display rest position to a plurality of different longitudinal positions beyond the platform edge (32) within a predetermined longitudinal range for enabling the weight display (30, 30b) to be longitudinally moved along the horizontal mounting surface (38) to a variable position for enabling the display (30, 30b) to be readable from above the supported package (24, 34) irrespective of the size of the package (24, 34) within that range.

Postal scale having extendable weight display for weighing oversize

A compact, modular, electronic measuring unit (10) constructed for enclosure within a small, portable housing (12) having a removable front wall (40) to provide access to the enclosure (28) formed within the housing (12). A measuring and indicator circuit card (60) is mounted within the enclosure (28) adjacent the front wall (40) while a power circuit card (58) is mounted within the enclosure adjacent the rear wall (22) thereof. Manual control units (44, 52, 54) are mounted on the front wall (40) of the housing (12) and are removable therewith. A moving dot matrix printer (56) is mounted within the housing (12) and is connected to receive data from the measuring and indicator circuit (60). This printer (56) is activated by one of the control units (50) on the front wall (40) of the housing (12), and includes a printer unit (116) which is driven in a first plane during the printing of a character on a record medium (178) and a record medium drive unit (136, 148, 150) which drives a record medium (178) in a second plane transverse to the first plane during the printing of a character.

Growing community of inventors

St. Johnsbury, VT, United States of America

Alec T Douglas