A DEVICE AT WASHING AND RINSING APPARATUSES FOR PRODUCING A FOAM

Abstract: A device in washing and rinsing apparatuses for continuously creating a foam, and conveying this to a nozzle (30), which device incorporates an injector (12), to the pressure side (14) of which is connectable a driving medium, e.g. water under pressure, and the suction side of which is connectable to a liquid, foam-forming detergent. The spray nozzle (18) of the injector is designed with an elongated, cross-sectionally very small hole (19), adapted to press the driving medium as a very thin jet into the diffusor (16) of the injector, that the diffusor (16) is slightly conical and on the inlet side provided with a portion of bigger, preferably much bigger cross-sectional area than the hole (19) of the spray nozzle (18), and that the diffusor (16) is arranged to open in an expansion chamber (20), to which is connectable a pressurized gas, e.g. air, for transport of the foam created therein to said nozzle (30).

Description: A device at washing and rinsing apparatuses for producing a foam The present invention refers to a device in washing and rinsi apparatuses for continuously creating a foam, and conveying th to a nozzle, which device incorporates an injector, to t pressure side of which is connectable a driving medium, e. water under pressure, and the suction side of which connectable to a liquid, foam-forming detergent. Background of the invention When cleansing with washing and rinsing apparatuses it very oft occurs that the object to be cleansed must be subjected cleansing with a chemical detergent during the cleansi procedure. This detergent is usually added to the cleansi liquid, which generally is water, by means of an injector. T detergent thus is admixed with rinsing water, which furthermo may have an increased water pressure, if the washing and rinsi apparatus is a high pressure apparatus. As the addition of t detergent occurs in connection with the rinsing, only a sma part of the detergent supplied will actively take part in t dissolving of the dirt. The major part of the detergent flushed away when the jet of water hits the object to cleansed. Manual application of the detergent has therefore be resumed, whereby the detergent will have a possibility activel to act upon the layer of dirt. From US-A-4, 505,431 is earlier known a foam-forming devic wherein water causes injection of a foam-forming fluid in injector, which is also connected to a source of pressurized air in such a manner that pressurized air is supplied to an annul slot around the injector diffusor. The quantity of air supplie in relation to the water quantity flowing through is rathe small, which means that a foam of high water content is formed i.e. a foam of rather short duration. The big excess of water i the foam furthermore causes the detergent to be heavily dilute resulting in an inferior cleansing effect. Purpose and most essential features of the invention The purpose of the present invention is to provide a device i known washing and rinsing apparatuses, which can be used for lo pressure apparatuses, operating at the pressure of the wate mains, as well as for high pressure apparatuses (water pressur of between 50 and 200 bar) and with which a foam treatment, i.e dissolving of the "dirt" with foamed detergent can be effected whereby the water consumption is as low as possible and therefor also the quantity of detergent supplied, and which quantity ca furthermore be controlled. Another purpose is to provide a devic by means of which it is possible to create a rich foam of lo duration and also by shifting a valve making possible rinsi with the same equipment and without limitation of the wat quantity. These tasks have been solved in that the spray nozzl of the injector is designed with an elongated, cross-sectionall very small hole, adapted to press the driving medium as a ve thin jet into the diffusor of the injector, that the diffusor slightly conical and on the inlet side provided with a portion bigger, preferably much bigger cross-sectional area than the ho of the spray nozzle and that the diffusor is arranged to open an expansion chamber, to which is connectable a pressurized ga e.g. air, for transport of the foam created therein to sa nozzle. Description of the drawings The invention will hereinafter be further described wi reference to an embodiment. Figure 1 shows the device according to the invention in a fro view. Figure 2 shows a section through the valve body according figure 1 in a somewhat bigger scale. Description of embodiment The device according to the invention consists of a valve body in which is included an injector 12 having on the pressure s 14 a connection 13 for a driving medium and on the suction si a connection 15 for a detergent. The driving medium in most ca is water under pressure. Behind the diffusor 16 of the injec as seen the direction of water flow is a room 17 in which arranged the spray nozzle 18 of the injector. This spray nozz is a plug provided with a central hole 19 and resting with shoulder against a corresponding stop in the valve, body 11. T spray nozzle 18 is sealed off against the pressure chamber 14 a its front part is almost cylindrical, thus that the water j emitted by the spray nozzle 18 through the hole 19 will have ti to fill the diffusor 16 before it enters an expansion chamber provided in connection to the diffusor. A pressure gauge 23 wi pressure regulator 24 and a stop valve 25 are connectable to t expansion chamber via the socket 21. At the front end of the valve body 11 a quick-coupling 27 for hose is connectable to the socket 26, the hose having at its fr end a lance 28 with a control valve 29 and a nozzle 30. Between the pressure chamber 14 and the expansion chamber 20 provided a by-pass conduit 31 having a closing and controlli valve 32, by means of which it is possible to by-pass t injector 12, which is then exerted to the same pressure at bo sides, whereby the injector is made inactive, thus that t production of foam ceases. In this position the device accordi to the invention is used for rinsing only. For adjustment of the quantity of detergent supplied there provided a quantity control valve 34 in the suction conduit 3 which is connected to the connection 15. It has proven itself that the size ratio between the hole 19 the spray nozzle 18, i.e. the hole diameter a and the diffuso cross-section b, at its inlet part and the pressure at which th driving medium, i.e. the water is supplied are of importance fo producing an optimum quantity of foam. At a pressure of 100 - 20 bar it has been found that a diameter a_ in the bore 19 of 0.8 m and a diffusor diameter b_ of 1.6 mm are appropriate. If the wate pressure is between 40 and 99 bar then a shall be 1.0 mm and 1.6 mm. At water pressure between 15 and 39 bar the measure shall be 2.3 mm and the hole diameter a 1.6 mm, whereas for water pressure between 5 and 14 bar a shall be 1.8 mm and b 2. mm. In this manner it is possible to cover the entire pressure rang (from 5-200 bar) with two different valve bodies 11, one having diffusor diameter b_ of 1.6 mm and another wherein the measure is 2.3 mm, and four different injector spray nozzles 18. Operating mode of the device When the stop valve 32 in the by-pass conduit 31 is in close position, the pressurized water via the spray nozzle 18 will for a jet, which in the suction chamber 17 creates a sub-pressure sucking in detergent in a quantity corresponding to the positio of the control valve 34. The water-detergent admixture, which, a a certain chosen size relation between the spray nozzle and th diffusor, can be e.g. 4 to 5 litres per minute, builds up counter-pressure in the diffusor, which is balanced against th pressurized air flowing into the expansion chamber 20 via ti conduit 22. An air pressure of about 5 - 6 bar at an air quantit of about 50 litres per minute has proven itself to give a optimum quantity of foam. The quantities of detergent and of ai are adjusted due to the foam pattern desired, to the importanc of the throwing length and to how rigid the foam shall be. B suitable choice of lance 28 and nozzle 30 it is furthermor possible to adjust the quantity of foam during work.

Claims: CLAIMS 1. A device in washing and rinsing apparatuses for continuous creating a foam, and conveying this to a nozzle (30), whi device incorporates an injector (12), to the pressure side (1 of which is connectable a driving medium, e.g. water und pressure, and the suction side of which is connectable to liquid, foam-forming detergent, c h a r a c t e r i z e d t h e r e i n, that the spray nozzle (18) of the injector is designed with elongated, cross-sectionally very small hole (19), adapted press the driving medium as a very thin jet into the diffus (16) of the injector, that the diffusor (16) is slightly conical and on the inlet si provided with a portion of bigger, preferably much bigger cros sectional area than the hole (19) of the spray nozzle (18), a that the diffusor (16) is arranged to open in an expansi chamber (20), to which is connectable a pressurized gas, e. air, for transport of the foam created therein to said nozz (30). 2. A device as claimed in claim 1, c h a r a c t e r i z e d t h e r e i n, that the spray nozzle (18) is a separate plug designed with shoulder adapted to separate the pressure chamber (14) of t injector from its suction chamber (17). 3. A device as claimed in claim 1, c h a r a c t e r i z e d t h e r e i n, that between the pressure side (14) of the injector (12) and t expansion chamber (20) of the device is provided a bypass condu (31) having av stop valve (32). 4. A device as claimed in claim 1, c h a r a c t e r i z e d t h e r e i n, that the quantity pressurized gas supplied to the expansi chamber (20) is considerably bigger than the quantity of drivin medium-detergent admixture supplied thereto, preferably at ratio of 10:1.

Inventors: CARLZON MANNE, DAHLIN STEN-HUGO, CARLZON, MANNE, DAHLIN, STEN-HUGO
Applicants: CARLZON MANNE, CARLZON, MANNE
Application year: 1988
Main classification: B05B7
IPC codes: B05B7, B08B3, G01N1, G01N35