AU634376B2

AU634376B2 - A portable high-pressure cleaner

Info

Publication number: AU634376B2
Application number: AU75403/91A
Authority: AU
Inventors: Karl Johan Klitgaard Frandsen
Original assignee: Kf Industri AS
Current assignee: Kf Industri AS
Priority date: 1990-03-20
Filing date: 1991-03-18
Publication date: 1993-02-18
Anticipated expiration: 2011-03-18
Also published as: AU7540391A; CA2078430A1; FI924170A; DK72490A; WO1991014517A1; JPH05507986A; DK72490D0; FI924170A0; DK166766B1; EP0521054A1

Description

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PCT

OPI DATE 21/10/91 AOJP DATE 21/11/91 A\PPLN. In 75403 91 PCT NUMBER PCT/DK91/00n INTERNATIONAL A 1. (PCT) (51) International Patent Classification 5 International Publication Number: WO 91/14517 B08B 3/02 (43) International Publication Date: 3 October 1991 (03.10.91) (21) International Application Number: (22) International Filing Date: Priority data: 0724/90 20 March PCT'DK91/00080 18 March 1991 (18.03.91) 1990 (20.03.90) (71) Applicant (for all designated States except US): K.F. IN- DUSTRI A'S Anholtvej 2, DK-9500 Hobro

(DK).

(72) Inventor; and Inventor/Applicant (for US onl1) FRANDSEN, Karl. Johan, Klitgaard [DK/DK]; Teglvaerksvinget 9. Stinesminde. DK-9500 Hobro (DK).

(74) Agent: GREGERSEN. Aarhus Patentkontor, Skanderborgvej 40, DK-8000 Aarhus C (DK).

(81) Designated States: AT, AT (European patent), AU. BF (European patent), BG. BR. CA. CH, CH (European patent), DE, DE (Utility model). DE (European patent), DK, DK (European patent). ES. ES (European patent).

FI, FR (European patent), GB, GB (European patent), GR (European patent). HU, IT (European patent), JP, KP, KR, LU, LU (European patent), MC. NL. NL (European patent), NO, PL. RO, SE. SE (European patent).

SU, US.

Published litlh international search report.

634 76 (54) Title: A PORTABLE HIGH-PRESSURE CLEANER (57) Abstract By a portable high-pressure cleaner (66) comprising a pump part with a pumping chamber (24) and belonging valve and displacement means (14, 22, 26) between a low-pressure part (10, 32) where the pumped medium, by way of example water, is supplied, and a high-pressure part (12) with a discharge connection to a utility tool, by way of example a jet pipe, and an engine, preferably an internal combustion engine, the displacement means comprise a hollow, cylindrical pump piston (14) which preferably via a crosshead connecting rods (18) and a crank is drive connected directly with an engine piston and which is permanently connected to the low-pressure part (10, 32) via intake openings (65) to the cavity of the pump piston, and an intake valve (22) positioned at an open front end of the pump piston, said intake valve being adapted to close the open front end of the pump piston (14) by forward movement of said pump piston towards a pressure valve (26) and the pumping chamber and to open the front end of the pump piston (14) by rearward movement of said pump piston (14) towards the low-pressure part 32).

1 A PORTABLE HIGH-PRESSURE CLEANER The present invention relates to a portable high-pressure cleaner, in particular for hobby purposes, and of the type described in the introductory part of claim 1.

For leisure-time or hobby purposes is known to produce lightweight and compact high-pressure cleaners. However, it is often a question of downward-dimensioned and equipmentwise versions of high-pressure cleaners for professional use, that is to say that known high-pressure cleaners for hobby-purposes normally also are encumbered with the same disadvantages as high-pressure cleaners for professional use including a relatively high price. Furthermore, known high-pressure cleaners of this type are relatively heavy units because they either include a conventional petrol engine or an electric motor. In the last-mentioned case in addition to connection to proper electricity supply a special security system is required because of the connection to a water supply.

From the disclosure of US Patent No. 3 446 156 is known a diffential pressure poppet valve comprising an improved discharge valve by a pump having a piston moveable in a normal back-and-forth cycle capable of forcing a fluid through a cylindrical passageway. The piston has a hollow interior chamber and includes an inlet ball valve located at the front end being cabable of moving between an open position during the backstroke where fluid may pass through the inlet valve from the interior chamber and a closed position during the forwardstroke where the ball is forced against a valve seat.

The invention has for its purpose to provide an improved high-pressure cleaner of the type mentioned initially, by means of which a significant use-wise flexibility and ini. 2 creased reliability are achieved even at reduced manufacturing costs.

The high-pressure cleaner according to the invention is distinctive in that the Pump piston consists of a thin-walled tube of stainless steel which via a crosshead, connecting rods and a crank mechanism is directly drive connected with an engine pi-ton of the drive engine and which is permanently connected to the low-pressure part via intake openings to the cavity of the pump piston, that the intake valve as per see knowv is positionec at an open front end of the pump piston, and that a valve member of the intake valve is connected to the pump piston in such loosely displaceable manner that the valve member by inertia stress is removed from the open front end, when the pump piston is moved rapidly towards the low-pressure part, and displaced towards the open end when the pump piston is moved rapidly in the opposite direction. In this manner is obtained a strongly improved high-pressure cleaner which in consequence of the simple and compact construction in particular is suited as a portable cleaning apparatus which despite the modest size has a very significant cleaning capacity. And furthermore, by means of simple constructional provisions is obtained an intake valve build together with the hollow pump piston which without valve spring means may operate with a relatively high on/off frequency (50 160 opening/ closing movements per second).

In order to obtain a simplified and sturdy construction the high-pressure cleaner according to the invention is such provided that the pump piston opposite the open front end has a concentric connecting part with small diameter, said connecting part being provided with a central, through-going bore provided with an internal thread, said threaded bore serves the purpose of fixing the pump piston to the crosshead and fixing a guiding pin (90) stretching central- /ro- SUBSTiTUTE SHEET 3 lv through the pump piston, on which guiding pin the valve memberfor the intake valve is iournaled.

Expediently the high-pressure cleaner according to the invention is such provided that said intake openings to the vavity of the pump piston being provided as a number of intake channels in an inclined, cylindrical reducing piece to the connecting part the axeses of said, intake channels stretching rearwards in an acute angle in relation to the centre-axis of the pump piston. Hereby in a simple manner is achieved an extra easy supply of water from the lowpressure part into the hollow pump piston both during the forward pumping movement and during the rearward intake movement of the pump piston.

In order to obtain a larger cleaning capacity and to utilize a sort of differential effect in the low-pressure part or on the intake-side of the pump piston the high-pressure cleaner according to the invention is such provided that a rearmost part of said hollow pump piston, said inclined, cylindrical reducing piece and the connecting part for the pump piston are stretching through the low-pressure part in the form of an intake chamber. By simple provisions the said differential effect is hereby obtained on the lowpressure side such that the supply of water into the hollow pump piston from the intake chamber is optimal during the pump stroke as well as during the intake stroke.

In the following the invention is described in more detail with reference to the drawing, in which:- Fig. 1 is a view partly in section of an embodiment of a high-pressure cleaner according to the invention as seen from above, Fig. 2 a side view partly in section of the high-pressure cleaner shown in Fig. 1, SS~3TTUT~ 4-.

Sr 4 Fig. 3 an enlarged sectional view of the pump part of the high-pressure cleaner shown in Fig. 1, Fig. 4 an enlarged sectional view of the pump part of the high-pressure cleaner shown in Fig. 2, Fig. 5 a side view partly in section of a preferred embodiment of a high-pressure cleaner according to the invention, Fig. 6 a view partly in section of the high-pressure cleaner shown in Fig. 5 as seen from above, Fig. 7 an end view partly in section as seen from the section line VII-VII in Fig. Fig. 8 a side view mainly in section of an embodiment of a pump part of the high-pressure cleaner according to the invention shown in Figs. 5 7, while, Fig. 9 is a sectional view of a pump piston for the pump part shown in Fig. 8 for a high-pressure cleaner according to the invention.

The high-pressure cleaner 2 shown in Figs. 1 and 2 comprises a pump part 4 shown in Fig. 3 and in part in Fig. 4,.

a crank mechanism 6 and a motor in the form of a petrol engine 8. The pump part 4 comprises a low-pressure side or part 10 and a high-pressure side or part 12 and a hollow, tubular pump piston 14 placed in between, which via a crosshead 16, connecting rods 18 and the crank mechanism 6 is drive connected directly with a drive piston 20 of the petrol engine 8. Furthermore, the pump part comprises an intake valve 22, a pumping chamber 24, a pressure valve 26 and a discharge stub 28 for the connection of a jet pipe.

7x 2 *Yy The pump piston 14 is opposite the intake valve 22 connected with a cylindrical connecting part 30 being connected with the crosshead 16 opposite the pump piston 14. A rearmnost part of the pump piston 14 and the connecting part 30 stretching on the low-pressure side 10 through an intake chamber 32 to which water at waterworks pressure (2 8 bar) is supplied through a ball valve 34 adapted to open by means of an activation rod 36, via a pivot arm 38 connected with a velocity regulator 40 (speeder) for the petrol engine 8. When the latter by way of example is running at idle speed (corresponding to about 3.000 rpm) the ball valve 34 is closed such that no water is supplied to the pump part 4 which at least shortly should stand to operate without water supply.

The intake valve 22 comprises a valve member 42 which at the open front end of the pump piston 14 is loosely, displaceable journaled in a valve holder 44 secured to the pump piston 14, that is that the valve holder 44 is displaced forwards and backwards together with the pump piston 14. The valve member 42 is guided in the valve holder 44 by means of a stem portion 46 facing forward and which in a way together with the valve member 42 constitutes the proper displacement surface of the pump piston 14. When the pump piston 14 including the valve holder 44 during operation is displaced rapidly forwards and backwards the valve member 42 will among other things as a consequence of the inertia stress automatically be pressed towards the open front end of the pump piston 14 when the latter during the pumping stroke is forwardly displaced, and be removed from the open front end of the pump piston 14 when the latter during the intake stroke is rearwardly displaced. During the pumping stroke the counterpressure in the pumping chamber of course will also actuate the intake valve 22 to close by pressing the valve member 42 towards the open front end of the pump piston 14.

I V- C? IVT 7 6 The pump piston 14 operates in a pump cylinder 48, which at the low-pressure side 10 of the pump part is closed by means of a stuffing box 50 through which the pump piston 14 also stretches. Opposite the stuffing box 50 the pumping chamber 24 is provided in the form of a ring-shaped member which like the other parts of the pump part 4 is secured in a surrounding plastic mantle 52. The latter may consist of two parts or be provided by casting in of the several parts of the pump part, as the plastic mantle 52 constitutes a foremost handle for the high-pressure cleaner 2.

Opposite the pump piston 14 the pumping chamber 24 forms an engagement surface for the pressure valve 26 as a valve member or valve disk 54 by means of a centre spindle 56 is displaceably journaled in a valve housing 58 which comprises a ring-shaped cavity 60 around a central guide bushing 62 for the centre spindle 56. The ring-shaped cavity 60 constitutes a holder for a compression spring 64 ensuring the pressing of the valve member 54 against the front side edge of the pumping chamber 24.

The tubular pump piston 14 is at the rear end, that is to say at the junction to the connecting part 30 provided with radial intake channels 65 which from the intake chamber 32 see to the supply of water from the low-pressure part into the hollow pump piston 14. In front of the intake channels 65 the pump piston 14 has enlarged diameter compared to that of the connecting part 30, that is to say that the pump piston 14 and the connecting part 30 at the lowpressure side 10 constitutes a sort of differential piston reciprocating in the intake chamber 32 and which results in supply of water from the intake chamber 32 into the hollow pump piston 14 during the forward pumping stroke as well as during the rearward intake stroke of the pump piston 14.

7 By the preferred embodiment of the high-pressure cleaner 66 shown in Figs. 5 7 the same references have been used for the parts which are recovered by the high-pressure cleaner 2 cfr. Figs. 1 4. Furthermore, the high-pressure cleaner 66 comprises a petrol tank surrounding the pump part 4, a carburettor operated by means of the speeder 40 placed in a handle 72 which as indicated by arrows 74 in addition is used as sup.ly channel for cooling air to the motor, a flywheel 76 with belonging ignition-system 78.

The pump part 4 of the high-pressure cleaner 66 is shown in more detail in Fig. 8 where among other things it may be seen that the pumping chamber 24 is provided in a ringshaped part 80, which in addition comprises an escape valve mechanism 82 as the ring-shaped part 80 at the front end is held in place against a combined holder part and valve housing part for the pressure valve 26 by means of a disc spring 84 such that the part 80 is allowed to be displaced in forward direction in case of a too high pressure behind the pressure valve 26, by way of example if a connected jet pipe is blocked so that the excess-pressure may be drained off via a lower radial opening 86.

By the high-pressure cleaner 66 the intake valve 22 is arranged in a different way than that of the high-pressure cleaner 2 where the valve member 22 is displaceably journaled in a valve housing 44. Instead a valve member 88 at the open front end of the hollow pump piston 14 is displaceably journaled on a valve pin 90 stretching centrally through the hollow pump piston 14 and secured to a support bushing 92 being secured inside a central bore 94 of the connecting part 30. The valve member 88 cooperates with a head part 96 of the valve pin 90 in such a way that the valve member 88 is allowed to be removed very little from the open front end of the pump piston 14 when the latter during the intake stroke is displaced rearwards etc. The r high-pressure cleaner 66 comprises like the high-pressure cleaner 2 a water supply 98 which is partly surrounded by a sound absorber 100.

1 j~ 1-

Claims

1. A portable high-pressure 66) cleaner comprising a pump part with a pumping chamber a pump piston an intake valve (22) between a low-pressure part (109 where the pumped medium, such as water, is supplied. and a h i rh-n-rpess"-- l -ri+ (12) with a discharge connection (28) to .Irsr ~-uuulr CULC an auxiliary tool, such as a let pipe, and a drive engine i th' form of an internal combustion engine c h a r a c t e r i z e d in that the pump piston (14) consists of a thin-wal' I tube of stainless steel which via a cross- head (16) connecting rods (18) and a crank mechanism (6) is directly drive connected with an engine piston (20) of the drive engine and which is permanently connected to the low-pressure part (10) via intake openings (65) to the cavity of the pump piston that the intake valve (22j as per see know) is positioned at an open front end of the pump piston and that a valve member (42, 88) of the intake valve (22, is connected to the pump piston (14) in such loosely displaceable manner that the valve member (42 88) by inertia stress is removed from the open front end, when the pump piston (14) is moved rapidly towards the low-pressure part and displaced towards the open end when the pump piston (14) is moved rapidly in the opposite direction. l J I L

2. A portable high-pressure cleaner according to claims 1, c h a r a c t e r i z e d in that the pump piston (14) op- posite the open front end has a concentric connecting part with small diameter, said connecting part (30) being provided with a central, through-going bore (94) provided with an internal thread, said threaded bore (94) serves the purpose of fixing the pump piston (14) to the crosshead (16) and fixing a guiding pin (90) stretching centrally through the pump piston on which guiding pin (90) the valve member (42. 88) for the intake valve is iournaled.

3. A portable high-pressure cleaner according to claims 1 and 2, c h a r a c t e r i z e d in that said intake ope- nings to the cavity of the pump piston (14) being provided as a number of intake channels (65) in an inclined, cylin- drical reducing piece to the connecting part (30) the axe- ses of said intake channels (65) stretching rearwards in an acute angle in relation to the centre-axis of the pump pi- ston (14).

4. A portable high-pressure cleaner according to claims 1 3, c h a r a c t e r i z e d in that a rearmost part of said hollow pump piston said inclined, cylindrical reducing piece and the connecting part (30) for the pump piston (14) are stretching through the low-pressure part (10) in the form of an intake chamber. (I