Apparatus for dispensing medium to high viscosity liquids with liquid flow detector and alarm
First Claim
1. An automatic liquid dispensing machine for dispensing sealants, mastics, adhesives and like medium to high viscosity liquids, said machine comprising medium to high viscosity sealant, mastic, adhesive and the like liquid automatic dispensing means, liquid pressure sensing means disposed in the liquid flow path of said automatic liquid dispensing means, said liquid pressure sensing means serving to derive a fluid pressure indicating electrical signal indicative of the instantaneous liquid pressure in said sealants, mastics, adhesives and the like medium to high viscosity liquid flow path, and electrical signal processing circuit means responsive to said liquid pressure indicating electrical signal, said signal processing circuit means comprising differentiating circuit means responsive to said liquid pressure indicating electrical signal for differentiating the said liquid pressure indicating electrical signal to derive a rate-of-change in liquid pressure electrical signal, and bubble indicator means responsive to said liquid pressure rate-of-change electrical signal for detecting the existence of an undesired rate-of-change in liquid pressure condition indicative of the occurrence of a bubble.
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Accused Products
Abstract
A medium to high viscosity liquid flow detector and alarm sub-system for use with apparatus for automatic liquid dispensing machines for mastics, sealants, adhesives, and the like, comprising a liquid pressure sensing device disposed in the liquid flow path of the liquid dispensing gun of the machine. The liquid pressure sensing device derives an output electrical signal indicative of the instantaneous liquid pressure in the liquid flow path. A differentiating circuit differentiates the liquid pressure indicating signal to derive a rate of change in fluid pressure signal. The rate-of-change signal is supplied to an indicator for signalling the existence of an undesired rate-of-change in liquid pressure condition and is indicative of a bubble or void in the liquid mastic, sealant, or the like being dispensed. The rate-of-change signal is supplied to a first comparator which also has supplied thereto an input bubble size reference signal that establishes a predetermined size bubble or void below which no alarm signal will be produced. Upon the occurrence of a bubble or void which is greater than that established by the adjustable bubble size reference signal, an output alarm signal is produced.
71 Citations
28 Claims
- 1. An automatic liquid dispensing machine for dispensing sealants, mastics, adhesives and like medium to high viscosity liquids, said machine comprising medium to high viscosity sealant, mastic, adhesive and the like liquid automatic dispensing means, liquid pressure sensing means disposed in the liquid flow path of said automatic liquid dispensing means, said liquid pressure sensing means serving to derive a fluid pressure indicating electrical signal indicative of the instantaneous liquid pressure in said sealants, mastics, adhesives and the like medium to high viscosity liquid flow path, and electrical signal processing circuit means responsive to said liquid pressure indicating electrical signal, said signal processing circuit means comprising differentiating circuit means responsive to said liquid pressure indicating electrical signal for differentiating the said liquid pressure indicating electrical signal to derive a rate-of-change in liquid pressure electrical signal, and bubble indicator means responsive to said liquid pressure rate-of-change electrical signal for detecting the existence of an undesired rate-of-change in liquid pressure condition indicative of the occurrence of a bubble.
- 10. A sealant, mastic, adhesive and like medium to high viscosity liquid dispensing gun and alarm system for an automatic sealant, mastic, adhesive and the like liquid dispensing machine for dispensing medium to high viscosity sealant, mastic, adhesive and the like liquids comprising liquid pressure sensing means disposed in the liquid flow path of said liquid dispensing gun, said liquid pressure sensing means serving to derive an output liquid pressure indicating electrical signal indicative of the instantaneous liquid pressure in said sealant, mastic, adhesive and the like medium to high viscosity liquid flow path, and signal processing circuit means responsive to said liquid pressure indicating electrical signal from the liquid pressure sensing means, said signal processing circuit means comprising differentiating circuit means responsive to said liquid pressure indicating electrical signal for differentiating the said liquid pressure indicating electrical signal to derive a rate-of-change in liquid pressure electrical signal, and bubble indicator means responsive to said liquid pressure rate-of-change electrical signal for detecting the existence of an undesired rate-of-change in liquid pressure condition indicative of the occurrence of a bubble.
- 19. The method of detecting discontinuities due to bubbles or voids occurring in the flow of medium to high visocity sealant, mastic, adhesive and the like liquids while being dispensed, said method comprising sensing the pressure of the sealant, mastic, adhesive and the like medium to high viscosity liquid being supplied under pressure to a dispensing gun for the medium to high viscosity liquid, deriving an output electric signal representative of the instantaneous liquid pressure of the sealant, mastic, adhesive and the like medium to high viscosity liquid being supplied to the dispensing gun, differentiating the liquid pressure indicating electric signal to derive a rate-of-change in liquid pressure electrical signal representative of abrupt changes in pressure of the liquid being dispensed which in turn is indicative of the possible occurrence of a bubble or void in the sealant, mastic, adhesive and like liquid being dispensed, and employed the rate-of-change in liquid pressure electrical signal to indicate the possible occurrence of a bubble or void in the liquid being dispensed.
Specification