Dilute phase powder pump and method for operating a dilute phase powder pump

Patent metadata

Field	Value
Publication number	US-2022016653-A1
Application number	US-201917309352-A
Country	US
Kind code	A1
Filing date	Dec 19, 2019
Priority date	Dec 31, 2018
Publication date	Jan 20, 2022
Grant date	—

Abstract

The invention relates to a dilute phase powder pump (51) for pumping powder, particularly coating powder, from a powder reservoir to a powder spray-coating device, comprising a powder inlet (80), which is or can be flow-connected to the powder reservoir, and a powder outlet (81), which is or can be flow-connected to the powder spray-coating device, the dilute phase powder pump (51) having also a powder pumping injector (100) with a motive fluid nozzle (1) and a converging inlet nozzle (11), and the dilute phase powder pump (51) having a valve device for optionally interrupting a flow connection between the powder inlet (80) of the dilute phase powder pump (51) and a powder inlet (5) of the motive fluid nozzle (1).

First claim

1 . A dilute phase powder pump for conveying powder from a powder reservoir to a powder spraying device, which comprises a powder inlet, which is fluidly connected or connectable to the powder reservoir, and a powder outlet, which is fluidly connected or connectable to the powder spraying device, wherein the dilute phase powder pump further comprises a powder-conveying injector having a drive nozzle and a collecting nozzle, and wherein the dilute phase powder pump comprises a valve device for selectively interrupting a fluidic connection between the powder inlet of the dilute phase powder pump and a powder inlet of the drive nozzle,
wherein the dilute phase powder pump further comprises a compressed air inlet device which serves to supply compressed air as purge air for cleaning/flushing the dilute phase powder pump or components provided upstream and downstream of the powder-conveying injector respectively, and which opens into the fluidic connection at least at one point between the powder inlet of the dilute phase powder pump and the powder inlet of the drive nozzle in order to selectively supply compressed air as purge air, wherein the compressed air inlet device opens into the fluidic connection at a point between the valve device and the powder inlet of the drive nozzle.

2 . The dilute phase powder pump according to claim 1 ,
wherein the valve device comprises a pneumatically actuatable pinch valve provided in a flow path between the powder inlet of the dilute phase powder pump and the powder inlet of the drive nozzle.

3 . The dilute phase powder pump according to claim 1 ,
wherein the collecting nozzle exhibits a stream collecting channel distanced axially opposite from the drive nozzle, and wherein the powder inlet of the drive nozzle is distanced axially opposite from the stream collecting channel.

4 . The dilute phase powder pump according to claim 3 ,
wherein the powder inlet of the drive nozzle is aligned with respect to an axis which coincides with a longitudinal axis defined by the stream collecting channel or runs parallel to the longitudinal axis defined by the stream collecting channel.

5 . The dilute phase powder pump according to claim 1 ,
wherein a pump housing is provided in which the powder-conveying injector is at least partially accommodated, wherein a powder supply channel is formed in the pump housing which fluidly connects the powder inlet of the dilute phase powder pump to the powder inlet of the drive nozzle, wherein the valve device is designed to disconnect a fluidic connection formed by the powder supply channel between the powder inlet of the dilute phase powder pump and the powder inlet of the drive nozzle.

6 . The dilute phase powder pump according to claim 5 ,
wherein the collecting nozzle exhibits a stream collecting channel distanced axially opposite from the drive nozzle, and wherein the powder inlet of the drive nozzle is distanced axially opposite from the stream collecting channel; and wherein the powder supply channel runs in a straight line along a longitudinal axis thereof, wherein the longitudinal axis of the powder supply channel coincides with a longitudinal axis defined by the stream collecting channel or runs parallel to a longitudinal axis defined by the stream collecting channel.

7 . The dilute phase powder pump according to claim 1 ,
wherein a device for the functional testing of the dilute phase powder pump or components of the dilute phase powder pump is provided.

8 . The dilute phase powder pump according to claim 7 ,
wherein the device for functional testing comprises at least one pressure sensor for detecting a static and/or dynamic pressure in an area in the fluidic connection between the powder inlet of the dilute phase powder pump and the powder inlet of the drive nozzle.

9 . The dilute phase powder pump according to claim 8 ,
wherein the at least one pressure sensor is designed to detect a static and/or dynamic pressure in an area in the fluidic connection between the valve device and the powder inlet of the drive nozzle.

10 . The dilute phase powder pump according to claim 8 ,
wherein the at least one pressure sensor is designed to detect the chronological progression of a static and/or dynamic pressure over a definable period of time.

11 . The dilute phase powder pump according to claim 8 ,
wherein a pump housing is provided in which the powder-conveying injector is at least partially accommodated, wherein a powder supply channel is formed in the pump housing which fluidly connects the powder inlet of the dilute phase powder pump to the powder inlet of the drive nozzle, wherein the valve device is designed to disconnect a fluidic connection formed by the powder supply channel between the powder inlet of the dilute phase powder pump and the powder inlet of the drive nozzle; and wherein a filter permeable to air but not to powder is allocated to the compressed air inlet device, wherein the at least one pressure sensor is connected to a compressed air path which extends from a compressed air line allocated to the compressed air inlet device to an air side of the filter, and wherein the filter separates the air side from the fluidic connection between the powder inlet of the dilute phase powder pump and the powder inlet of the drive nozzle.

12 . The dilute phase powder pump according to claim 7 ,
wherein the device for functional testing comprises at least one actual powder rate value sensor which is arranged in or near the powder-conveying injector on or in a flow path of the powder/conveying air mixture at the powder outlet of the dilute phase powder pump for detecting a corresponding actual powder rate value delivered by the powder-conveying injector.

13 . The dilute phase powder pump according to claim 1 ,
wherein the dilute phase powder pump comprises a conveying air inlet allocated to the powder-conveying injector for supplying conveying air to the drive nozzle and a supplementary air inlet allocated to the powder-conveying injector for supplying supplementary air into a flow path of a powder/conveying air mixture at the powder outlet of the dilute phase powder pump, wherein at least one air setting element is provided for setting a volume of conveying air supplied to the conveying air inlet per unit of time and/or for setting a volume of supplementary air supplied to the supplementary air inlet per unit of time.

14 . The dilute phase powder pump according to claim 13 ,
wherein a device for the functional testing of the dilute phase powder pump or components of the dilute phase powder pump is provided; wherein the device for functional testing comprises at least one pressure sensor for detecting a static and/or dynamic pressure in an area in the fluidic connection between the powder inlet of the dilute phase powder pump- and the powder inlet of the drive nozzle; and wherein the device for functional testing comprises an evaluation device for evaluating the static and/or dynamic pressure value detected by the at least one pressure sensor and/or for evaluating a chronological progression of the static and/or dynamic pressure detected by the at least one pressure sensor, wherein the evaluation device is designed to detect at least one of the following situations on the basis of the pressure value detected by the at least one pressure sensor and/or the progression of pressure detected by the at least one pressure sensor as well as on the basis of the volume of conveying air or supplementary air respectively supplied to the conveying air inlet and/or the supplementary air inlet per unit of time:
wear and/or degree of wear of the collecting nozzle;

Assignees

• Gema Switzerland Gmbh

Inventors

• Tobler Roger
• Sanwald Marco
• Mauchle Felix

Classifications

• B65G53/40

  Feeding or discharging devices · CPC title

• F04F5/44

  Component parts, details, or accessories not provided for in, or of interest apart from, groups F04F5/02 - F04F5/42 · CPC title

• B05B7/1472 Primary

  Powder extracted from a powder container in a direction substantially opposite to gravity by a suction device dipped into the powder · CPC title

• F04F5/14

  the inducing fluid being elastic fluid · CPC title

• F04F5/54

  Installations characterised by use of jet pumps, e.g. combinations of two or more jet pumps of different type · CPC title