Piston limit sensing for fluid application

Patent metadata

Field	Value
Publication number	US-12135048-B2
Application number	US-201816123680-A
Country	US
Kind code	B2
Filing date	Sep 6, 2018
Priority date	Sep 7, 2017
Publication date	Nov 5, 2024
Grant date	Nov 5, 2024

Abstract

A liquid delivery system includes a source of hydraulic fluid and a hydraulic cylinder fluidically coupled to the source of hydraulic fluid and having a hydraulic piston movable between first and second limit positions. The liquid delivery system includes a rod connected to the piston and extending out of the hydraulic cylinder and a sensor device located outside the hydraulic cylinder and configured to sense a position of the rod and to generate a signal indicating the sensed position. The liquid delivery system includes a liquid cylinder comprising a liquid piston, operably driven by the rod, to pump a liquid along a flow path to a fluid applicator.

First claim

What is claimed is:

1. A liquid delivery system comprising:
a source of hydraulic fluid;
a hydraulic cylinder fluidically coupled to the source of hydraulic fluid and having a hydraulic piston movable between a first limit position and a second limit position;
a rod connected to the hydraulic piston and extending out of the hydraulic cylinder;
a liquid cylinder comprising a liquid piston, operably driven by the rod, to pump a liquid along a flow path to a fluid applicator;
a housing assembly disposed between the hydraulic cylinder and the liquid cylinder, the housing assembly including a first wall and a second wall that are spaced apart to define a first opening and a second opening;
a sheath and a collar which are disposed within the housing assembly and couple the liquid piston to the rod, wherein at least one of the sheath or the collar comprises a ferrous metal;
a sensor device disposed entirely within the housing assembly and located outside the hydraulic cylinder, the sensor device comprising a potting body that hermitically seals a magnet therein, and the sensor device configured to generate a sensor signal indicative of a sensed position of the at least one of the collar or the sheath comprising the ferrous metal;
a controller configured to:
derive a position of the hydraulic piston based on the sensor signal; and
based on the position of the hydraulic piston, actuate a solenoid valve to control a flow of the hydraulic fluid between from the source of hydraulic fluid and the hydraulic cylinder;

a first cover configured to couple to the first wall and cover the first opening; and
a second cover spaced apart from the first cover and configured to couple to the second wall and cover the second opening.

2. The liquid delivery system of claim 1 wherein the liquid comprises paint.

3. The liquid delivery system of claim 1 , wherein the sheath is cylindrical.

4. The liquid delivery system of claim 1 , wherein the first opening and the second opening are on opposite sides of the collar.

5. The liquid delivery system of claim 1 , wherein the sensor device is directly mounted to an interior side of one of the first wall or the second wall.

6. The liquid delivery system of claim 1 wherein the sensor device comprises a first sensor device corresponding to the first limit position and configured to generate a first sensor signal indicative of a first sensed position of the at least one of the collar or the sheath, the liquid delivery system further comprising:
a second sensor device corresponding to the second limit position and located outside the hydraulic cylinder, the second sensor device configured to generate a second sensor signal indicative of a second sensed position of the at least one of the collar or the sheath.

7. The liquid delivery system of claim 6 , wherein the first cover and the second cover are removable to provide access to an interior of the housing assembly.

8. The liquid delivery system of claim 7 , wherein the first sensor device and the second sensor device are directly coupled to an interior wall of the housing assembly, the interior wall of the housing assembly being separate from the first cover and the second cover such that the first sensor device and the second sensor device remain disposed on the interior wall of the housing assembly when the first cover and the second cover are removed.

9. The liquid delivery system of claim 8 , wherein a potting body of the first sensor device comprises fasteners disposed within the potting body of the first sensor device and configured to facilitate coupling of the first sensor device to the interior wall of the housing assembly, and wherein a potting body of the second sensor device comprises fasteners disposed within the potting body of the second sensor device and configured to facilitate coupling of the second sensor device to the interior wall of the housing assembly.

10. The liquid delivery system of claim 1 , wherein the sensor device comprises a wireless communication component configured to wirelessly transmit the sensor signal.

11. The liquid delivery system of claim 10 wherein the sensor device is coupled to a battery power source.

12. A paint delivery system comprising:
a piston pump assembly including:
a source of hydraulic fluid;
a hydraulic cylinder coupled to the source of hydraulic fluid and having a piston movable between a first limit position and a second limit position;
a rod connected to the piston and extending out of the hydraulic cylinder;
a solenoid valve configured to control a flow of a hydraulic fluid between the source of hydraulic fluid and the hydraulic cylinder;
a housing structure coupled to the hydraulic cylinder, the housing structure including a first wall and a second wall that are spaced apart to define a first opening and a second opening;
a paint pump coupled to the piston by a collar assembly to move paint from a paint reservoir to a paint applicator, the collar assembly disposed within the housing structure and including:
a collar; and
a sheath,
wherein at least one of the collar or the sheath comprises a ferrous material; and

a first non-contact sensor device comprising a first potting body that hermitically seals a first magnet therein, the first non-contact sensor device corresponding to the first limit position and configured to generate a first sensor signal indicative of a first sensed position of the at least one of the collar or the sheath, the first non-contact sensor device disposed entirely within the housing structure and located outside the hydraulic cylinder;
a second non-contact sensor device comprising a second potting body that hermitically seals a second magnet therein, the second non-contact sensor device corresponding to the second limit position and configured to generate a second sensor signal indicative of a second sensed position of the at least one of the collar or the sheath, the second non-contact sensor device disposed entirely within the housing structure and located outside the hydraulic cylinder;
a controller configured to derive a position of the piston based on first sensor signal or the second sensor signal;
a first cover configured to couple to the first wall and cover the first opening; and
a second cover spaced apart from the first cover and configured to couple to the second wall and cover the second opening.

13. The paint delivery system of claim 12 , wherein the controller is configured to receive the first sensor signal and the second sensor signal and to control the solenoid valve based on the first sensor signal or the second sensor signal.

14. The paint delivery system of claim 12 , wherein the first non-contact sensor device is directly mounted to an interior side of one of the first wall or the second wall, and wherein the second non-contact sensor device is directly mounted to the interior side of the one of the first wall or the second wall.

15. The paint delivery system of claim 12 , wherein the first opening and the second opening are on opposite sides of the collar assembly.

Assignees

• Wagner Spray Tech Corp

Inventors

• Zientara Daniel Robert
• Nguyen Lam Huu
• Wu Fei

Classifications

• F04B15/02

  the fluids being viscous or non-homogeneous · CPC title

• B05B9/007

  At least a part of the apparatus, e.g. a container, being provided with means, e.g. wheels, for allowing its displacement relative to the ground · CPC title

• F04B17/06

  Mobile combinations · CPC title

• F04B49/065

  and making use of computers · CPC title

• F04B9/105

  reciprocating movement of the pumping member being obtained by a double-acting liquid motor · CPC title