LEVEL DETECTOR FOR A HOT MELT SYSTEM

• US 20200056922A1
• Filed: 08/20/2018
• Published: 02/20/2020
• Est. Priority Date: 08/20/2018
• Status: Active Grant

• Current Assignee: Hot Melt Technologies, Inc.
• Original Assignee: Hot Melt Technologies, Inc.
• Inventors: Tanury, Bryan, Spearing, Ed, Holzman, Colin
• Granted Patent: US 10,641,637 B2
• Time in Patent Office: Days
• CPC Class Codes: G01F 23/0007 for discrete indicating and measuring G01F23/02 - G01F23/28 take precedence
• CPC Class Codes: G01F 23/20 by measurement of weight, e.g. to determine the level of stored liquefied gas
• CPC Class Codes: G01F 23/804 containing circuits handling parameters other than liquid level
• CPC Class Codes: G05D 9/12 characterised by the use of electric means

Abstract

An illustrative example level detector for a hot melt system includes a scale having a load cell and a controller having an indicator configured to alert an operator when a weight detected by the load cell has decreased by a user-selected maximum allowable amount.

Claims

1. A level detection system for a hot melt unit, comprising:

a scale having a load cell, the load cell configured to be placed beneath a tank of a hot melt unit; and

a controller having an indicator configured to alert an operator when a weight of the hot melt unit detected by the load cell has decreased by a user-selected maximum allowable amount.

2. The level detection system of claim 1, wherein the scale is rectangular and configured to fit beneath the hot melt unit.

3. The level detection system of claim 2, wherein the scale has four load cells, one at each corner of the rectangular scale.

4. The level detection system of claim 1, wherein the controller is configured to periodically receive signals from the load cell.

5. The level detection system of claim 1, wherein the indicator is a visual indicator.

6. The level detection system of claim 1, wherein the indicator is an audible alarm.

7. The level detection system of claim 1, comprising a user interface configured to allow the operator to select the maximum allowable amount.

8. The level detection system of claim 7, wherein the user interface has a reset button for the operator to reset the indicator.

9. The level detection system of claim 7, wherein the user interface is configured to allow the operator to select between a manual refill mode and an automatic refill mode.

21. The level detection system of claim 8, wherein the indicator is both an audible alarm and a visual indicator

10. A hot melt system, comprising:

a melt unit having a melt tank;

a scale arranged beneath the melt unit; and

a controller having an indicator configured to alert an operator when the scale detects a weight of the melt unit has decreased by a user-selected maximum allowable amount.

11. The hot melt system of claim 10, wherein the user-selected maximum allowable amount is set by the operator.

12. The hot melt system of claim 10, wherein the scale comprises four load cells, one positioned near each of four corners of the melt unit.

13. The hot melt system of claim 10, wherein the indicator is an audible alarm.

14. The hot melt system of claim 10, wherein the indicator is a visual indicator.

15. The hot melt system of claim 10, wherein the controller is configured to periodically receive signals from the scale.

16. A method of maintaining a desired fill level in a hot melt tank using a level detection system having a scale situated to detect a weight of a hot melt tank, the method comprising:

setting a tank full weight;

determining a user-selected desired minimum weight of the hot melt tank;

periodically measuring the weight of the hot melt tank with the scale; and

alerting an operator when the weight of the hot melt tank falls below the desired minimum weight, wherein alerting the operator comprises sounding an audible alarm.

17. The method of claim 16, wherein the determining the desired minimum weight is based upon selecting a maximum allowable weight decrease, and wherein the desired minimum weight corresponds to the tank full weight minus the maximum allowable weight decrease.

18. (canceled)

19. The method of claim 18, comprising:

refilling a tank of the hot melt system; and

resetting the tank full weight of the hot melt system.

20. The method of claim 19, comprising silencing the alarm after refilling the tank.