Hydraulic control system for weighing
First Claim
1. A method for accurately weighing a load lifted by an hydraulically operated lifting device of the type having lift arms hydraulically operated to lift a loaded container and empty it;
- said method comprising the steps of;
lifting a container means with lift arm means of an hydraulic system means;
operating the hydraulic system means to cause the lift arm means to lift the container means to a reference position;
generating a signal when the lift arm means have lifted said container means to the reference position;
tapping off and bypassing hydraulic fluid from a lift circuit of the hydraulic system means of the lifting device;
lowering said lift arm means at a slower rate than the normal rate of descent of the hydraulic system means;
generating a signal when said lift arm means have lowered said container means to a weighing position;
generating an analog electric signal from transducer means communicating with said tapped-off hydraulic fluid;
receiving said analog electrical signal generated by the transducer means at an analog/digital converter means for generating a digital record; and
,activating said hydraulic system means to cause said lift arm means to lift said container means to an emptying position for unloading contents therefrom.
1 Assignment
0 Petitions
Accused Products
Abstract
An hydraulic bypass control system for tapping off the lift circuit of an hydraulically operated lifting device. The bypass control system slowly releases hydraulic fluid from the lift circuit and directs it back to the reservoir in a controlled manner so a load is smoothly moved from a reference position to a weighing position. Reliable weighing may be obtained by avoiding dynamic shaking, vibration and pressure surges, which permits the weighing step to be reliably made at the same point or range and affords precise calibration of a load transducer with a weighing instrument to be made.
29 Citations
5 Claims
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1. A method for accurately weighing a load lifted by an hydraulically operated lifting device of the type having lift arms hydraulically operated to lift a loaded container and empty it;
- said method comprising the steps of;
lifting a container means with lift arm means of an hydraulic system means; operating the hydraulic system means to cause the lift arm means to lift the container means to a reference position; generating a signal when the lift arm means have lifted said container means to the reference position; tapping off and bypassing hydraulic fluid from a lift circuit of the hydraulic system means of the lifting device; lowering said lift arm means at a slower rate than the normal rate of descent of the hydraulic system means; generating a signal when said lift arm means have lowered said container means to a weighing position; generating an analog electric signal from transducer means communicating with said tapped-off hydraulic fluid; receiving said analog electrical signal generated by the transducer means at an analog/digital converter means for generating a digital record; and
,activating said hydraulic system means to cause said lift arm means to lift said container means to an emptying position for unloading contents therefrom. - View Dependent Claims (2, 3, 4, 5)
- said method comprising the steps of;
Specification