AU2011200124A1

AU2011200124A1 - Cleaning apparatus

Info

Publication number: AU2011200124A1
Application number: AU2011200124A
Authority: AU
Inventors: Holger Krogsgard
Original assignee: Nilfisk Advance AS
Current assignee: Nilfisk AS
Priority date: 2010-01-15
Filing date: 2011-01-13
Publication date: 2011-08-04
Anticipated expiration: 2031-01-13
Also published as: DK2345484T3; EP2345484A1; AU2011200124B2; EP2345484B1

Abstract

CLEANING APPARATUS 5 By the invention a cleaning apparatus for cleaning an elevated surface comprising, in combination, a high pressure cleaner (40), a gun (100) having a trigger (104), and a outer tube, which may be a telescopic tube (60), surrounding a flexible hose (70) for a fluid and a detergent, wherein a valve (116) may be provided in, or at, the gun (100), and the valve (116) is regulating the supply of the detergent to an injector (150) which 10 is provided in the flow path of the fluid, and wherein the flexible hose (70) is terminated in a nozzle (80) attached to the distal end of the outer tube, is provided. A method of cleaning a roof of a residential house is also provided. Fig. 1 is to be published with the abstract.

Description

Pool Section 29 Regulation 3.2(2) AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: invention Title: Cleaning apparatus The following statement is a full description of this invention, including the best method of performing it known to us: P11 IABAU/0610 1 CLEANING APPARATUS The present invention relates to an apparatus and a method for cleaning elevated structures such as residential house roofs. 5 In many countries roofs on residential houses get covered by organic matter, such as algae, which affect the appearance of the houses negatively. Further, the organic matter can accelerate the natural deterioration of the roof, leading to an increased need for roof maintenance and ultimately a costly roof replacement. Roof problems 10 associated with organic matter typically occur in areas with high amounts of rain and warm winters and cold summers. Attempts to remove organic matter from a residential house roof include mechanical cleaning relying on brooms or brushes or a high pressure water jet to forcefully remove 15 the organic matter, and chemical cleaning where an appropriate detergent, typically mixed with water, is applied to the roof. Mechanical cleaning, using brooms or brushes or other tools which mechanically contact the roof, may lead to damage to the roof if used too forcefully. Likewise cleaning using only a high pressure water jet may also damage the roof due to the high pressure needed. A combination of a high pressure 20 water and a detergent is therefore preferred as this reduces the risk of damaging the roof. Further the cleaning, whether mechanical or chemical, should be performable without the need for a person standing on the roof or on a ladder, i.e. preferably the cleaning should be performable by a person standing on the ground as this reduces the risk of injuries. 25 For cleaning of residential roofs or other elevated structures, numerous devices typi cally comprising long wands or poles have been described in amongst others US6905080, US20020190145, EP2105550, DE20202532 (utility model) and FR2901718. The devices rely on an external source of high pressurized water and, if 30 used to apply a detergent solution, requires that the detergent is provided to the de vices already mixed with water. For chemical cleaning of organic deposits, the deter gent, typically based on Benzalkoniumchlorid, should be mixed with water to a specific concentration for it to be effective. 35 A readily available source of high pressurized water for use by a consumer cleaning a residential roof is a consumer high pressure cleaner.

2 Although many consumer high pressure cleaners are capable of adding a detergent through an injector mounted at the high pressure pump, or an injector mounted in a lance connected to the pump, the detergent being sucked into and mixed with the wa 5 ter due to the pressure differences between the water and the detergent supply as the water passes the injector, the correct concentration of detergent in the water cannot be achieved as a typical consumer high pressure cleaner with an injector mounted at the pump typically only reach a concentration of around 2-5%. Increasing the concentra tion of detergent to water through increasing the pressure difference is possible but 10 results in decreased performance during normal high pressure cleaning, i.e. when no detergent is added. Thus the above described devices for cleaning residential roofs cannot apply an affective mixture of detergent and water to a residential roof. Further, the above described devices do not allow a consumer to adjust the concentration of detergent, while cleaning a residential roof, without interrupting cleaning, thus making 15 the cleaning less efficient and more time-consuming. Techniques related to the mixing of water and detergents are described in amongst others US5669558, W02008086952, US3361300, US20060234616 and W09809739. 20 An object of the present invention is to simplify and rationalize chemical cleaning of residential roofs. A further object of the present invention is to provide a cleaning apparatus which is usable together with a consumer high pressure cleaner by a consumer standing on the 25 ground. A yet further object of the present invention is to provide a cleaning apparatus capable of supplying a detergent solution to a residential roof in an effective mixture. 30 A further object of the present invention is to provide a method for applying a detergent solution to a residential roof. The above objects, as well as numerous further objects which will be evident from the following detailed description of preferred embodiments of the cleaning apparatus of 35 the present invention is according to a first aspect of the present invention obtained by a cleaning apparatus for cleaning an elevated surface comprising, in combination: 3 a high pressure cleaner, a gun having a trigger, and an outer tube surrounding a flexible hose for a fluid and a detergent, wherein an injector is provided in the flow path of said fluid, and wherein said flexible hose is ter 5 minated in a nozzle attached to the distal end of said outer tube. The elevated surface may be a surface on a residential house or other low rise build ing such as a wall, roof, window, the surfaces of a rain gutter, the surfaces of a chim ney, but preferably a roof of a residential house. However, it is contemplated that the 10 elevated surface could also be a surface on a bridge, a surface on a crane, a surface on a wind turbine, a surface on a vehicle etc. The elevated surface is typically 2-16 m above the user's feet. It is however contemplated within the context of the present invention that also a de 15 pressed surface such as the walls of a manhole or a cellar staircase, where it would be expedient to achieve cleaning without actually entering the manhole or cellar staircase, could be cleaned by the cleaning apparatus according to the first aspect of the present invention. 20 The high pressure cleaner according to the first aspect of the present invention may be adapted to supply the fluid to the gun at high pressure. By using a high pressure cleaner a high concentration, such as 10%, of detergent in the fluid may be reached The gun according to the first aspect of the present invention may be in fluid commu 25 nication with the high pressure cleaner via a high pressure hose. The trigger may be adapted to interrupt the flow of fluid. The trigger may be connected to a main valve provided in the flow path of the fluid. The main valve may be a ball valve. The gun may be held by a user of the cleaning apparatus. 30 The outer tube according to the first aspect of the present invention may be attached to the gun and may surround a flexible hose for the fluid and a detergent. The outer tube may be elongated and may be made of metal or plastic. The fluid according to the first aspect of the present invention may be water. The de 35 tergent according to the present invention may be supplied from a detergent container. The detergent may be supplied to the gun through a hose.

4 In the context of the present invention the term detergent is to be understood as com prising any agent useful for cleaning an object. The detergent may be for example a tenside, a soap, a surfactant, a herbicide, an acid, an abrasive, an oxidant, an enzyme 5 etc. The injector according to the first aspect of the present invention may be a based on the Venturi effect. The injector may be enclosed in the gun or may alternatively be at tached to the gun or may alternatively be provided at the gun such as on the high 10 pressure hose or in a fitting fluidly connecting the high pressure hose to the gun. The flexible hose according to the first aspect of the present invention may be in fluid communication with the gun. The flexible hose may be bendable, but may also be stretchable. 15 In one preferred embodiment of the cleaning apparatus according to the first aspect of the present invention the outer tube is a telescopic tube. This is advantageous as it allows the cleaning apparatus to be more easily transportable and storageable while still allowing elevated surfaces to be reached for cleaning. The telescopic tube may 20 include co-axial tube sections joined by locking mechanisms. In one preferred embodiment of the cleaning apparatus according to the first aspect of the present invention the cleaning apparatus further comprises a valve provided in, or at, said gun, the valve being adapted to regulate the supply of the detergent to the 25 injector. This is advantageous as it allows a user to adjust the concentration of deter gent in the fluid without interrupting cleaning by letting go of the gun. The valve according to the first aspect of the present invention may be actuable by the user of the cleaning apparatus without interrupting cleaning. The valve may be en 30 closed in the gun or may alternatively be attached to the gun or may alternatively be provided at the gun such as on the hose supplying detergent from the detergent con tainer or in a fitting fluidly connecting the hose from the detergent container to the gun. The valve may be a ball valve, a globe valve or a needle valve etc, but any valve may be used provided that it allows a regulation of the supply of the detergent to the injec 35 tor. It is preferred that the valve allows stepless regulation, but the valve may also be an on-off valve.

5 It is however contemplated within the context of the present invention that the valve could be substituted by a steplessly or steppedly regulated pump and the injector could be substituted by a fluid connection between the pump and the flow path of the 5 fluid, wherein the pump may be an electric pump. In one preferred embodiment of the cleaning apparatus according to the first aspect of the present invention the gun further includes a main valve actuable by the trigger for interrupting the flow of the fluid and the injector is provided downstream of the main 10 valve. By providing the injector downstream of the main valve the injector is protected from the high pressure arising when the main valve is closed. This is advantageous as it lessens the risk of leaks in the injector and allows the injector to be constructed out of less expensive materials. 15 In one embodiment of the cleaning apparatus according to the first aspect of the present invention the elevated surface is a roof of a house and the cleaning apparatus is adapted to allow a user standing on the ground adjacent the house to clean the roof. By standing on the ground the safety for the user is increased. 20 In one embodiment of the cleaning apparatus according to the first aspect of the present invention the high pressure cleaner is a conventional consumer high pressure cleaner. This is advantageous as it decreases the cost for a user, which is in the possession of 25 a consumer high pressure cleaner, wishing to clean an elevated surface. In the context of the present invention the term conventional consumer high pressure cleaner is to be understood as comprising high pressure cleaners delivering a fluid at a maximum pressure below 200 bar. 30 In one embodiment of the cleaning apparatus according to the first aspect of the present invention the trigger of the gun is lockable when triggered. This allows the user to adjust his grip of the gun to actuate the valve to regulate the detergent supply without interrupting cleaning. 35 6 In one embodiment of the cleaning apparatus according to the first aspect of the present invention the outer tube is may be a telescopic tube having a fully extended length of at least 2 m, such as least 3 m, preferably at least 5 m. This is advantageous as it allows the user to clean the roof of most residential homes. 5 In one embodiment of the cleaning apparatus according to the first aspect of the present invention the outer tube may be a telescopic tube comprising a plurality of co axial tube sections joined by locking mechanisms, each of the plurality of tube sections being independently lockable in relation to an adjacent tube section. 10 This allows the telescopic tube to assume any length between a fully retracted length, where all tube sections are nested within each other, to a fully extended length, thus achieving the advantage that the telescopic tube may be shortened when the fully ex tended length is not needed, thus simplifying the handling of the cleaning apparatus 15 for the user. In one embodiment of the cleaning apparatus according to the first aspect of the present invention the cleaning apparatus further comprises a support structure adapted to support the outer tube. This simplifies the handling of the cleaning appara 20 tus for the user. The support structure may have a first part for supporting the outer tube and a second part being supported by the ground on which the user stands, or by an additional user of the cleaning apparatus. 25 In one embodiment the support structure includes a tripod or a monopod. The support structure may be telescopic. Alternatively the support structure may include a harness worn by the user and connected to the outer tube for supporting the outer tube. Alter natively the support structure may include, at the nozzle, a wheel being rollable on, or 30 a runner being slideable over, the elevated surface to support the outer tube by sup porting the nozzle on the elevated surface. In one embodiment of the cleaning apparatus according to the first aspect of the present invention the cleaning apparatus further comprises a counterweight attached 35 to the gun or the outer tube to counter balance the weight of the outer tube and/or the thrust from the nozzle.

7 In one embodiment of the cleaning apparatus according to the first aspect of the present invention the flexible hose is a low pressure hose. 5 In the context of the present invention the term low pressure hose is to be understood as a hose having a maximum pressure limit before failure which is less than the pres sure limit before failure of the high pressure hose establishing fluid communication between the high pressure cleaner and the gun. 10 This may be possible as the flexible hose may be downstream of the main valve whe reby the high pressures which arise when the main valve is closed are not present in the flexible hose. This is advantageous as the weight and cost of the flexible hose decreases. The flexi 15 ble hose may have a larger flow area than the high pressure hose. In one embodiment of the cleaning apparatus according to the first aspect of the present invention the valve is selectively actuable to allow the detergent to be injected into the fluid at a rate adapted to achieve a concentration in the range from 0% to at 20 least 10% detergent in the fluid. This is advantageous as it allows the cleaning apparatus according to the first aspect of the present invention to be used for various cleaning requiring various concentra tions of detergent. This also allows various types of detergents, requiring various dilu 25 tions, to be used. Further, when the concentration of detergent in the fluid is zero per cent, the cleaning apparatus may be used to rinse off the elevated surface. In one embodiment of the cleaning apparatus according to the first aspect of the present invention the detergent is benzalkoniumchloride and the fluid is water. 30 This is advantageous as benzalkoniumchloride is an effective detergent for cleaning an elevated surface, in particular removing organic deposits from a roof. In one embodiment of the cleaning apparatus according to the first aspect of the 35 present invention the nozzle is angleable and/or produces a pencil jet.

8 This is advantageous as it increases the reach of the cleaning apparatus. Further, it is contemplated within the context of the present invention that by angling the nozzle, and thus changing the direction of the thrust from the nozzle, the handling of the cleaning apparatus may be simplified as the thrust from the nozzle may be directed to 5 counteract the weight of the outer tube. According to a second aspect of the cleaning apparatus according to the present in vention a method for cleaning the roof of a residential house by a user standing on the ground adjacent the house is provided comprising the steps of: 10 Providing a cleaning apparatus according to the first aspect of the present inven tion, and applying the fluid and the detergent to the roof. In a preferred embodiment of the method according to the second aspect of the 15 present invention the method according to the second aspect of the present invention further comprises the step of: Adjusting the valve to obtain a specific concentration of said detergent in said fluid. 20 This is advantageous as it allows the concentration of detergent in the fluid to be ad justed to suit the detergent used, the extent of cleaning needed and the type of roof, which increases the efficiency of the cleaning. In one embodiment according to the second aspect of the present invention the 25 cleaning of the roof comprises the removal of organic deposits selected from the group comprising algae, lichen, mold and moss, or combinations thereof, from the roof. The cleaning apparatus according to the first aspect of the present invention has the advantage that it allows a user, while standing on the ground, to apply an effective 30 concentration of detergent to an elevated surface such as a residential roof using a normal consumer high pressure cleaner as source of pressurized water, without the risk of falling down from the roof, thus increasing the safety of cleaning. In a preferred embodiment of the cleaning apparatus according to the first aspect of 35 the invention the user may easily, and without interrupting cleaning by letting go of the gun, adjust the concentration of detergent for different types of roofs, different types of 9 detergents and/or different types to be performed, thus simplifying and rationalizing the cleaning. The invention and its many advantages will be described in more detail below with 5 reference to the accompanying schematic drawings which for the purpose of illustra tion show some non-limiting embodiments and in which Fig. 1 shows the cleaning of a roof using one embodiment of the cleaning apparatus according to the present invention, 10 Fig. 2 shows the cleaning apparatus, Fig. 3 shows the gun, Fig. 4 shows the foam generating nozzle, Fig. 5 shows in cross section the gun, and Fig. 6 shows in cross section the injector in the gun. 15 Fig. 1 shows the cleaning of a roof, designated the reference numeral 12, of a resi dential house, designated the reference numeral 10, by a user, designated the refer ence numeral 30, standing on the ground, designated the reference numeral 1, adja cent the house 10. The user 30 grasps a gun, in its whole designated the reference 20 numeral 100, in one of his hands and grasps a telescopic tube, in its whole designated the reference numeral 60, with his other hand. The telescopic tube 60 is supported by a support structure, designated the reference numeral 90, shown as a monopod, how ever the support structure 90 may be omitted if desired. A consumer high pressure cleaner, designated the reference numeral 40 receives water from a mains water 25 hose, designated the reference numeral 46, and supplies pressurized water to the gun 100 via a high pressure hose, designated the reference numeral 42. Detergent is sup plied to the gun 100 from a detergent container, designated the reference numeral 200 through a detergent hose, designated the reference numeral, 202. Within the gun 100 the pressurized water and the detergent are mixed, as will be described in more detail 30 with reference to figs. 5-6 below, resulting in a detergent solution, designated the ref erence numeral 20, which is led through a flexible hose, designated the reference numeral 70, extending through, and surrounded by, the telescopic tube 60, to a noz zle, designated the reference numeral 80, wherefrom it is applied to the roof 12. 35 The consumer high pressure cleaner 40 could for example be a Nilfisk C 100.5 con sumer high pressure cleaner having a maximum water pressure of about 100 bar and 10 a water flowrate of about 440 I/h. As an alternative to placing the detergent container 200 on the ground adjacent the user 30 and supplying the detergent through the de tergent hose 202, the detergent container 200 could be directly connected to the gun, omitting the detergent hose 202, whereby it could serve as a counterweight to balance 5 the telescopic tube 70. Further, although the outer tube of the first aspect of the present invention is shown as telescopic tube 60 in figs 1-6, a non-telescopic outer tube may also be used. 10 Fig. 2 shows the telescopic tube 60 in more detail. The telescopic tube includes a plu rality of tube sections, one of which is designated the reference numeral 62 and a plu rality of locking mechanisms, one of which is designated the reference numeral 64, each of which may be independently actuable by the user to permit or hinder as de sired the telescopic movement between two neighbouring tube sections. One end of 15 the telescopic tube 60 is connected to a gun 100, and the other end of the telescopic tube 60 is connected to the nozzle 80. The tube sections 62 are preferably made of metal such as aluminium, but may also be made from carbon or glass fibre reinforced plastic or composite. The locking me 20 chanisms 64 are preferably made from plastic or metal. Fig. 3 shows the gun 100 attached to the telescopic tube 60. The gun 100 has a han dle, designated the reference numeral 102, and a trigger, designated the reference numeral 104, to allow the user 30 (not shown) to open/close the flow of pressurized 25 water from the consumer high pressure cleaner 40 (not shown) which supplies pressu rized water to the gun 100 via the high pressure hose 42. Detergent can be sucked in via a suction inlet, designated the reference numeral 106, which will be shown in more detail in fig. 6, supplied by the detergent container 200 (not shown) via the detergent hose 202. A control knob, designated the reference numeral 108, is located on the gun 30 100 where it can be easily manipulated by the user 30 (not shown). The flow of pres surized water is mixed with the detergent and the resulting detergent solution 20 (not shown) is led to the nozzle 80 (not shown) via the flexible hose 70 which runs through the telescoping tube 60. The flexible hose 70 forms a loop, designated the reference numeral 72, which accumulates any excess of flexible hose 70 and allows the flexible 35 hose 70 to move, as indicated in fig. 3 by the double arrow designated the reference sign A, into, or out of the gun 100 as the telescopic tube 60 is extended or retracted 11 respectively. The telescopic tube 60 may for example be retracted for convenient sto rage. The internal routing of the flexible hose will be described in more detail with ref erence to fig. 5 below. 5 The gun is typically molded out of plastics which may be carbon or glass fibre rein forced. The gun may also be made of metal. Preferably the gun 100 is made from two molded halves assembled by screws. The flexible hose 70 is typically made out of rubber or plastics, which may be rein 10 forced by Kevlar or other synthetic fibres. Fig. 4 shows the nozzle 80 connected to the telescopic tube 60 ejecting the detergent solution 20 as a pencil jet. The nozzle 80 includes an pivoting connection, designated the reference numeral 82, allowing the detergent solution 20 to be directed, and a tip, 15 designated the reference numeral 84, which allows the detergent solution to be ap plied to the roof as a pencil jet or as a wider spray by turning the tip 84 as desired by the user 30 (not shown). The nozzle 80 is typically molded out of plastic but may in clude metal components in the tip. 20 Fig. 5 shows in cross section the gun 100. The trigger 104 activates a main valve, designated the reference numeral 110, which allows pressurized water to flow from the consumer high pressure cleaner 40 (not shown) via the high pressure hose 42 and an inlet, designated the reference numeral 112, to an outlet, designated the reference numeral 114. An injector, in its whole designated the reference numeral 150, is con 25 nected to the main valve 110 and the outlet 114 to allow detergent supplied by the detergent container 200 (not shown) via detergent hose 202 to be sucked from the suction inlet 106 through a valve, designated the reference numeral 116, for mixing with the pressurized water. The telescopic tube 60 is attached to the gun 100 and the flexible hose 70 leads the detergent solution from the outlet 114, in the loop 72, 30 through an aperture, designated the reference numeral 118, into the gun 100 and through the telescopic tube 60 to the nozzle 80 (not shown). The flexible hose 70 is anchored to the nozzle 80 and the outlet 114, thus it may run freely within the gun 100 and the telescopic tube 60, allowing any excess of flexible hose 70, such as when the telescopic tube 60 is retracted, to be expelled from the telescopic tube 60 and the gun 35 100 through the aperture 118 as indicated by the double arrow A to accumulate in the loop 72.

12 Fig. 6 shows in cross section the injector 150. The flow of pressurized water from the consumer high pressure cleaner 40 (not shown), indicated by an arrow designated the reference numeral 44, draws in detergent, indicated by an arrow designated the refer 5 ence numeral 204, due to the high velocity, and subsequently the reduced pressure, of the pressurized water as it passes a restriction, designated the reference numeral 152, in the injector 150. The detergent valve 116 can be actuated through rotation of the control knob 108 (not shown), thereby reducing or increasing the flow of detergent indicated by the arrow 204. 10 13 List of reference signs and numerals with reference to the figures: A. Double arrow indicating movement of the flexible hose 70 1. Ground 10. Residential house 12. Roof 20. Detergent solution 30. User 40. Consumer high pressure cleaner 42. High pressure hose 44. Arrow indicating flow of pressurized water 46. Mains water hose 60. Telescopic tube 62. Tube section 64. Locking mechanism 70. Flexible hose 72. Loop 80. Nozzle 82. Pivoting connector 84. Tip 90. Support structure 100. Gun 102. Handle 104. Trigger 106. Suction inlet 108. Valve control knob 110. Main valve 112. Inlet 114. Outlet 116. Valve 118. Aperture 150. Injector 152. Restriction 200. Detergent container 202. Detergent hose 204. Arrow indicating flow of detergent

Claims

1. A cleaning apparatus for cleaning an elevated surface-comprising, in combination: a high pressure cleaner (40), 5 a gun (100) having a trigger (104), and an outer tube surrounding a flexible hose (70) for a fluid and a detergent, wherein an injector (150) is provided in the flow path of said fluid, and wherein said flexible hose (70) is terminated in a nozzle (80) attached to the distal end of said outer tube. 10

2. The cleaning apparatus according to claim 1, said outer tube being a telescopic tube (60).

3. The cleaning apparatus according to any preceding claim, further comprising a 15 valve (116) provided in, or at, said gun (100), said valve (116) being adapted to regu late the supply of said detergent to said injector (150).

4. The cleaning apparatus according to any preceding claim, said gun (100) further including a main valve (110) actuable by said trigger (104) for interrupting the flow of 20 said fluid and said injector (150) being provided downstream of said main valve (110).

5. The cleaning apparatus according to any preceding claim, said elevated surface being a roof (12) of a house (10) and said cleaning apparatus being adapted to allow a user (30) standing on the ground (1) adjacent said house (10) to clean said roof (12). 25

6. The cleaning apparatus according to any preceding claim, said high pressure cleaner being a conventional consumer high pressure cleaner (40).

7. The cleaning apparatus according to any preceding claim, said trigger (104) of said 30 gun (100) being lockable when triggered.

8. The cleaning apparatus according to any of the claims 2-7, said telescopic tube (60) having a fully extended length of at least 2 m, such as least 3 m, preferably at least 5 m. 35 15

9. The cleaning apparatus according to any of the claims 2-8, said telescopic tube (60) comprising a plurality of co-axial tube sections (62) joined by locking mechanisms (64), each of said plurality of tube sections (62) being independently lockable in relation to an adjacent tube section. 5

10. The cleaning apparatus according to any preceding claim, said cleaning apparatus further comprising a support structure (90) adapted to support said outer tube.

11. The cleaning apparatus according to any preceding claim, said flexible hose (70) 10 being a low pressure hose.

12. The cleaning apparatus according to any of the claims 3-11, said valve (116) being selectively actuable to allow said detergent to be injected into said fluid at a rate adapted to achieve a concentration in the range from 0% to at least 10% detergent in 15 said fluid.

13. The cleaning apparatus according to any preceding claim, said detergent being benzalkoniumchloride and said fluid being water. 20

14. The roof cleaning apparatus according to any preceding claim, said nozzle (80) being angleable and/or producing a pencil jet.

15. A method for cleaning the roof (12) of a residential house (10) by a user (30) standing on the ground adjacent said house (10) comprising the steps of: 25 Providing a cleaning apparatus according to any preceding claim, and applying said fluid and said detergent to said roof (12). 30