Powder conveying chamber for a dense phase powder pump and dense phase powder pump comprising a powder conveying chamber

Patent metadata

Field	Value
Publication number	US-12447485-B2
Application number	US-202218576739-A
Country	US
Kind code	B2
Filing date	Jul 6, 2022
Priority date	Jul 9, 2021
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

A powder conveying chamber for a dense-phase powder pump for conveying powder, in particular coating powder, has an end region via which the powder conveying chamber is or can be fluidically connected to a powder line, wherein the end region of the powder conveying chamber is configured as a transition region and designed to reduce an effective flow cross-section of the powder conveying chamber to an effective flow cross-section of the powder line and/or to an effective flow cross-section of a valve arranged between the powder conveying chamber and the powder line, in particular a pinch valve. In particular, a cleaning system is associated with the end region, with which the end region can be supplied with cleaning air in the form of pressurized air, in order to keep the end region free of powder deposits or in order to remove powder deposits in the end region.

First claim

The invention claimed is:

1. A powder conveying chamber for a dense phase powder pump for conveying powder, wherein the powder conveying chamber comprises at least one air exchange opening which is designed and formed separately from a cleaning air outlet of an end region of the powder conveying chamber, for alternately connecting fluidly to a vacuum line or vacuum source or to a compressed air supply line or compressed air source for drawing powder into the powder conveying chamber, or pneumatically expelling a portion of powder present within the powder conveying chamber, wherein the end region of the powder conveying chamber is fluidly connected or connectable to a powder line, and is configured as a transition region and designed to reduce an effective sectional area of flow of the powder conveying chamber to an effective sectional area of flow of the powder line and/or to an effective sectional area of flow of a valve, arranged between the powder conveying chamber and the powder line,
wherein:
the end region is allocated a cleaning system via which cleaning air in the form of compressed air can be supplied to the end region, in order to keep the end region free of powder deposits or to remove deposits of powder at the end region; and
at least part of a wall area of the end region forming the end region of the powder conveying chamber is designed as a porous wall area more permeable to compressed air but less permeable to powder.

2. The powder conveying chamber according to claim 1 ,
wherein the end region of the powder conveying chamber has at least one cleaning air outlet for blowing out the cleaning air in a powder conveying path defined by the transition region of the powder conveying chamber.

3. The powder conveying chamber according to claim 1 ,
wherein the cleaning system has a filter element at least in part tapering conically which is permeable to air but not to powder, wherein the filter element is or can be accommodated in a filter housing able to be supplied with cleaning air in the form of compressed air, wherein the filter element is or can be releasably connected to an end region of a cylindrical main body region of the powder conveying chamber by its larger end region in terms of diameter, and wherein the filter element is or can be releasably connected to an end region of the powder line or to an end region of a valve arranged between the powder conveying chamber and the powder line by its smaller end region in terms of diameter.

4. The powder conveying chamber according to claim 1 ,
wherein a control device is assigned to the cleaning system which is designed to fluidly connect at least one cleaning air outlet of the end region of the powder conveying chamber to a compressed air supply line or a compressed air source when needed, wherein the control device is designed to fluidly connect the at least one cleaning air outlet of the end region of the powder conveying chamber to the compressed air supply line or the compressed air source during a cleaning operation; and/or
wherein the control device is designed to fluidly connect the at least one cleaning air outlet of the end region of the powder conveying chamber to the compressed air supply line or compressed air source during a powder output cycle of the powder conveying chamber.

5. The powder conveying chamber according to claim 4 ,
wherein the control device is designed to regulate, as a function of an operating state and/or operating cycle of the powder conveying pump, the volume of compressed air to be supplied to the at least one cleaning air outlet of the end region of the powder conveying chamber per unit of time, wherein the control device is designed to supply a higher volume of compressed air per unit of time to the at least one cleaning air outlet of the end region of the powder conveying chamber during a cleaning operation compared to the volume of compressed air to be supplied to the at least one cleaning air outlet per unit of time during the powder output mode.

6. The powder conveying chamber according to claim 1 ,
wherein the end region of the powder conveying chamber is fluidly connected or connectable to the powder line by means of a pinch valve, wherein the pinch valve exhibits an effective sectional area of flow in its open state, and wherein the end region of the powder conveying chamber is designed to reduce an effective sectional area of flow of the powder conveying chamber to the effective sectional area of flow of the pinch valve in its open state.

7. The powder conveying chamber according to claim 1 ,
wherein the powder conveying chamber comprises a cylindrical main body region having a substantially uniform effective sectional area of flow.

8. The powder conveying chamber according to one of claims 1 to 7 ,
wherein the end region of the powder conveying chamber is a first end region, and the powder conveying chamber further comprises an oppositely disposed second end region, wherein the powder conveying chamber is or can be fluidly connected to a first powder line via the first end region and is or can be fluidly connected to a second powder line via the second end region, wherein the first and/or second end region of the powder conveying chamber is/are implemented as a transition region and designed to reduce an effective sectional area of flow of the powder conveying chamber to an effective sectional area of flow of the corresponding powder line, and wherein a cleaning system is in each case allocated to the first and/or second end region via which cleaning air in the form of compressed air can be supplied to the respective end region, in order to keep the respective end region free of powder deposits or to remove deposits of powder at the end region.

9. A dense phase powder pump for conveying coating powder from a first powder reservoir to a second downstream powder reservoir or to a downstream powder spray coating gun or device for spraying coating powder, wherein the dense phase powder pump has at least one powder conveying chamber according to claim 1 which is fluidly connected or connectable to the first powder reservoir via a powder inlet and to the second powder reservoir, or to the powder spray coating gun or device for spraying coating powder respectively, via a powder outlet, wherein at least one powder inlet valve is provided at the powder inlet and at least one powder outlet valve is provided at the powder outlet.

10. The dense phase powder pump according to claim 9 ,
wherein the at least one powder inlet valve and the at least one powder outlet valve have substantially the same effective sectional area of flow in their respective open state; or
wherein the powder inlet valve exhibits a larger effective sectional area of flow in the open state than an effective sectional area of flow of the powder outlet valve in its open state.

11. The dense phase powder pump according to claim 9 , wherein the dense phase powder pump is designed as a single-chamber dense phase powder pump and only has a single powder conveying chamber for the conveyance of coating powder.

12. The dense phase powder pump according to claim 9 ,
wherein the dense phase powder pump is designed as a multi-chamber dense phase powder pump and has a plurality of powder conveying chambers connected in parallel to each other for the conveyance of coating powder.

13. The dense phase powder pump according to claim 9 ,
wherein the at least one powder conveying chamber has the powder inlet at the end region which is a first end region, and has the powder outlet at an oppositely disposed second end region, wherein the at least one powder inlet valve and at least one powder outlet val

Assignees

• Gema Switzerland Gmbh

Inventors

• Sanwald Marco
• Michael Hanspeter
• Sutter Erich

Classifications

• B65G53/28

  Systems utilising a combination of gas pressure and suction (inducing feed of the materials by suction in gas pressure systems B65G53/14) · CPC title

• B05B15/55

  using cleaning fluids · CPC title

• B05B7/1459 Primary

  comprising a chamber, inlet and outlet valves upstream and downstream the chamber and means for alternately sucking particulate material into and removing particulate material from the chamber through the valves (conveying material in bulk by using a combination of gas pressure and suction B65G53/28; pumps in general F04B; apparatus for repeatedly measuring and separating a predetermined volume of fluent solid material from a supply or container G01F11/00) · CPC title