US3792801A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoplastic applicator with self-cleaning supply reservoir
Assignee: Nordson Corp
•
Filing: 1971-10-29
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Granted: 1974-02-19
•
Expires: 1991-10-29
Abstract
Abstract An applicator for melting thermoplastic material and supplying the molten or liquid material under pressure and at a controlled temperature to an applicator head. The material is melted by a heated grid through which it passes to a storage reservoir. From the reservoir it is pumped to a gun type applicator head. The pump is a single piston double-acting pump that is driven by an air motor. The liquid reservoir, the pump, the applicator gun, and the hose connecting the gun to the pump are all heated and maintained at an even temperature so that there are neither hot spots nor cold spots in the system. The applicator incorporates a self-cleaning mechanism for cleaning the grid and the tank by heating the degraded carbonaceous hot melt material to a temperature at which it is decomposed and converted to a powdered ash that is easily removed.
Inventors
- 👤 R Baker
- 👤 E Nord
- 👤 A Reighard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:48
CPC Classifications
B; B05; B05C; B05C11/00; B05C11/10; B05C11/1042; B29; B29B; B29B13/00; B29B13/02; B29B13/022; F; F04; F04B; F04B15/00; F04B15/04; F04B53/00; F04B53/10; F04B53/12; F04B53/125; F04B53/126; F04B9/00; F04B9/08; F04B9/10; F04B9/103; F04B9/105
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
182 words
An apparatus for melting and dispensing thermoplastic material comprising a hopper for receiving the thermoplastic material while in a solid state, said hopper having a continuous side wall, a bottom wall and an open top for receiving said material, a discharge opening in said bottom wall, said bottom wall having a heating surface exposed to said thermoplastic material and means for heating said surface so as to melt solid thermoplastic material contained in said hopper, a liquid reservoir located beneath and in fluid communication with said bottom wall of said hopper, said reservoir having a continuous side wall and a bottom wall, an applicator head including a discharge nozzle and an inlet, means incLuding a pump and a conduit connecting said applicator head inlet to said liquid reservoir, said pump being mounted upon the inside surface of said liquid reservoir side wall and in intimate contact with said reservoir side wall over a sufficiently large area to enable heat to be transferred to said pump through said reservoir side wall, and means located externally of said liquid reservoir for heating said pump.
Claim 2
Independent Claim
182 words
An apparatus for melting and dispensing thermoplastic material comprising a hopper for receiving the thermoplastic material while in a solid state, said hopper having a continuous side wall, a bottom wall and an open top for receiving said material, a discharge opening in said bottom wall, said bottom wall having a heating surface exposed to said thermoplastic material and means for heating said surface so as to melt solid thermoplastic material contained in said hopper, a liquid reservoir located beneath and in fluid communication with said bottom wall of said hopper, said reservoir having a continuous side wall and a bottom wall, an applicator head including a discharge nozzle and an inlet, means incLuding a pump and a conduit connecting said applicator head inlet to said liquid reservoir, said pump being mounted upon the inside surface of said liquid reservoir side wall and in intimate contact with said reservoir side wall over a sufficiently large area to enable heat to be transferred to said pump through said reservoir side wall, and means located externally of said liquid reservoir for heating said pump.
Claim 3
Independent Claim
25 words
The apparatus of clam 1 which further includes means for heating said liquid reservoir to maintain liquid contained in said reservoir in a liquid condition.
Claim 4
Independent Claim
25 words
The apparatus of clam 1 which further includes means for heating said liquid reservoir to maintain liquid contained in said reservoir in a liquid condition.
Claim 5
Dependent Claim
63 words
The apparatus of claim 2 which further includes means for cleaning said hopper bottom wall surface and said liquid reservoir, said cleaning means including means for causing said means for heating said hopper bottom wall surface and said means for heating said liquid reservoir to heat to a temperature sufficiently high to completely decompose said material and convert it to a powdered ash.
Claim 6
Dependent Claim
43 words
The apparatus of claim 3 in which said cleaning means is operable to cause said means to heat said hopper bottom wall surface and said means for heating said reservoir to heat to a temperature in excess of 700*F. but less than 1,500*F.
Claim 7
Dependent Claim
30 words
The apparatus of claim 3 in which said cleaning means causes said hopper bottom wall heating means and said reservoir heating means to heat to a temperature of approximately 1,000*F.
Claim 8
Dependent Claim
43 words
The apparatus of claim 1 in which said pump heating means includes a heater element mounted on the exterior of said liquid reservoir in such a manner that heat may be transferred from said element through said reservoir side wall to said pump.
Claim 9
Dependent Claim
25 words
The apparatus of claim 6 which further includes means for heating the side walls of said liquid reservoir and additional means for heating said conduit.
Claim 10
Dependent Claim
44 words
The apparatus of claim 7 in which all of said heating means comprises electrical heaters and further including control elements for independently controlling the flow of electricity to said reservoir heating means, said conduit heating means, and said hopper bottom wall surface heating means.
Claim 11
Dependent Claim
61 words
The apparatus of claim 8 which further includes a cover housing surrounding and enclosing said liquid reservoir and reservoir heaters, said cover housing being divided into two compartments separated by an insulated divider wall, one of said compartments enclosing said reservoir and the other compartment enclosing electrical elements of an electrical control panel for controlling the temperature of said heating means.
Claim 12
Dependent Claim
24 words
The apparatus of claim 9 which further includes a fan contained in said other compartment for cooling said other electrical control panel enclosing compartment.
Claim 13
Independent Claim
187 words
An apparatus for melting and dispensing thermoplastic material comprising means including a liquid reservoir for receiving the thermoplastic material while in a solid state and for melting said solid thermoplastic material to convert it to a liquid state and for holding said liquid thermoplastic material while maintaining it in a liquid state, said liquid reservoir having a continuous side wall and a bottom wall, an applicator head including a discharge nozzle and an inlet, means including a pump connecting said applicator head inlet to said liquid reservoir, said pump being mounted internally of said liquid reservoir upon the inside surface of said reservoir side wall, said pump being in intimate contact with said reservoir side wall over a sufficiently large area to enable heat to be transferred to said pump through said reservoir side wall, and said reservoir heater means including a heater element mounted upon the exterior of said reservoir side wall for heating said pump, said heater element being mounted directly opposite said pump on the exterior of said side wall so as to facilitate transfer of heat through said side wall into said pump.
Claim 14
Independent Claim
187 words
An apparatus for melting and dispensing thermoplastic material comprising means including a liquid reservoir for receiving the thermoplastic material while in a solid state and for melting said solid thermoplastic material to convert it to a liquid state and for holding said liquid thermoplastic material while maintaining it in a liquid state, said liquid reservoir having a continuous side wall and a bottom wall, an applicator head including a discharge nozzle and an inlet, means including a pump connecting said applicator head inlet to said liquid reservoir, said pump being mounted internally of said liquid reservoir upon the inside surface of said reservoir side wall, said pump being in intimate contact with said reservoir side wall over a sufficiently large area to enable heat to be transferred to said pump through said reservoir side wall, and said reservoir heater means including a heater element mounted upon the exterior of said reservoir side wall for heating said pump, said heater element being mounted directly opposite said pump on the exterior of said side wall so as to facilitate transfer of heat through said side wall into said pump.
Claim 15
Dependent Claim
24 words
The apparatus of claim 11 which further includes a conduit extending between said pump and said aPplication head, and means for heating said conduit.
Claim 16
Dependent Claim
32 words
The apparatus of claim 12 in which all of said heating means comprises electrical heaters and further including control elements for independently controlling the flow of electrical power to said heating means.
Claim 17
Dependent Claim
44 words
The apparatus of claim 11 which further includes means for cleaning said liquid reservoir, said cleaning means including means for causing said reservoir heater means to heat to a temperature sufficiently high to completely decompose said material and convert it to a powdered ash.
Claim 18
Dependent Claim
34 words
The apparatus of claim 14 in which said cleaning means is operable to cause said reservoir heater means to heat said reservoir to a temperature in excess of 700*F. but less than 1, 500*F.
Claim 19
Dependent Claim
23 words
The apparatus of claim 14 in which said cleaning means causes said reservoir heating means to heat to a temperature of approximately 1,000*F.
Claim 20
Dependent Claim
27 words
The apparatus of claim 14 in which said cleaning means includes a high temperature thermostat set to a temperature in excess of 700*F. but less than 1,500*F.
Claim 21
Independent Claim
180 words
An apparatus for melting and dispensing thermoplastic material comprising means including a liquid reservoir for receiving and holding the thermoplastic material while in a liquid state, said reservoir having a side wall and a bottom wall, an applicator head, means including a pump connecting said applicator head to said liquid reservoir, said pump being mounted internally of said liquid reservoir upon an inside surface of said reservoir side wall, said pump being in intimate contact with said reservoir side wall over a sufficiently large area to enable heat to be transferred to said pump through said reservoir side wall, means including a heater element mounted upon the exterior of said reservoir side wall for heating said pump, said heater element being mounted directly opposite said pump on the exterior of said side wall so as to facilitate transfer of heat through said side wall into said pump, and means for cleaning said liquid reservoir, said cleaning means including means for heating said reservoir to a temperature sufficiently high to completely decompose said material and convert it to a powdered ash.
Claim 22
Independent Claim
180 words
An apparatus for melting and dispensing thermoplastic material comprising means including a liquid reservoir for receiving and holding the thermoplastic material while in a liquid state, said reservoir having a side wall and a bottom wall, an applicator head, means including a pump connecting said applicator head to said liquid reservoir, said pump being mounted internally of said liquid reservoir upon an inside surface of said reservoir side wall, said pump being in intimate contact with said reservoir side wall over a sufficiently large area to enable heat to be transferred to said pump through said reservoir side wall, means including a heater element mounted upon the exterior of said reservoir side wall for heating said pump, said heater element being mounted directly opposite said pump on the exterior of said side wall so as to facilitate transfer of heat through said side wall into said pump, and means for cleaning said liquid reservoir, said cleaning means including means for heating said reservoir to a temperature sufficiently high to completely decompose said material and convert it to a powdered ash.
Claim 23
Dependent Claim
32 words
The apparatus of claim 18 in which said reservoir heating means is operable to heat said reservoir to a temperature in excess of 700*F. but less than 1,500*F. to clean said reservoir.
Claim 24
Dependent Claim
25 words
The apparatus of claim 18 in which said reservoir heating means heats said reservoir to a temperature of approximately 1, 000*F. to clean said reservoir.
Claim 25
Dependent Claim
28 words
The apparatus of claim 18 in which said reservoir cleaning means includes a high temperature thermostat set to a temperature in excess of 700*F. but less than 1,500*F.
References Cited (Backward Citations)
US825386A
Cited
US1061433A
Cited
US1785607A
Cited
US2206674A
Cited
US2563085A
Cited
US3121158A
Cited
US3377466A
Cited
US3531023A
Cited
US3585361A
Cited
US3598282A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-18 | 1977-08-20 | 1978-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-18 | 1981-08-20 | 1982-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-18 | 1985-08-20 | 1986-02-19 | $7700.00 | Window Closed / Lapsed |