EP1833346A1

EP1833346A1 - Cleaning head comprising a radial piston pump and surface cleaning device comprising said type of cleaning head

Info

Publication number: EP1833346A1
Application number: EP05810606A
Authority: EP
Inventors: Felix Treitz
Original assignee: Alfred Kaercher SE and Co KG
Current assignee: Alfred Kaercher SE and Co KG
Priority date: 2004-12-23
Filing date: 2005-11-18
Publication date: 2007-09-19
Anticipated expiration: 2025-11-18
Also published as: DE102004063202A1; EP1833346B1; US20080006715A1; ATE474494T1; DE502005009983D1; WO2006072277A1; US7600698B2

Abstract

The invention relates to a cleaning head (15) which is used to impinge a surface which is to be cleaned upon a pressurised cleaning fluid. Said cleaning head comprises at least one spray arm (41, 42, 43) which is rotationally mounted about a rotational axis (29) and is maintained on the at least one nozzle (46) which can be fed with a cleaning fluid by a pressure pump. The invention also relates to a surface cleaning device (10) which is provided with said type of cleaning head (15). The aim of the invention is to further develop the cleaning surface device and the cleaning head such that the surface cleaning device can be handled in a simple manner. As a result, the pressure pump is integrated into the cleaning head (15).

Description

CLEANING HEAD WITH RADIAL PISTON PUMP AND FLAT CLEANING UNIT WITH SUCH CLEANING HEAD

The invention relates to a cleaning head for acting on a surface to be cleaned with cleaning fluid under pressure, with at least one spray arm, which is rotatably mounted about a rotation axis and on which at least one nozzle is held, which is supplied from a pressure pump cleaning liquid.

Moreover, the invention relates to a surface cleaning device with such a cleaning head.

By means of surface cleaning devices, for example, a floor surface can be effectively cleaned. For this purpose, a pressure pump can be connected to the cleaning head, with the aid of which pressurized cleaning liquid can be supplied to the at least one nozzle. The nozzle is held on a spray arm, which is rotatably mounted about a rotation axis. As a result, the nozzle when dispensing the cleaning liquid can perform a rotary movement together with the spray arm, so that the surface to be cleaned can be acted upon by a liquid jet circulating on a circular path. As a result, an effective cleaning can be achieved, however, it is desirable to simplify the handling of the surface cleaning device.

Object of the present invention is therefore to develop a cleaning head of the type mentioned in such a way that it allows a simplified handling of a surface cleaning device with such a cleaning head. This object is achieved in a cleaning head of the generic type according to the invention that the pressure pump is integrated into the cleaning head.

Such a configuration has the advantage that a stationary pressure pump which is in flow communication with the cleaning head via a pressure hose can be dispensed with. The handling of a surface cleaning device with such a cleaning head is therefore considerably simplified.

It is advantageous if the cleaning head has a rotor housing which surrounds an eccentric and is rotatable relative to the eccentric about the axis of rotation, wherein at least one spray arm is fixed to the rotor housing and in the spray arm a delivery piston is slidably mounted in accordance with the orbital motion of the rotor housing the eccentric is drivable within the spray arm to a reciprocating motion, wherein the delivery piston dips into a cylinder chamber, which communicates with the at least one nozzle in flow communication and the cleaning liquid can be fed. Such a configuration allows a particularly compact design of the cleaning head. It forms, as a combination of at least one spray arm rotatable about a rotation axis, on which at least one nozzle is held, and a pressure pump, a unit which can be guided by the user, for example along a floor surface. The cleaning head can also be used for the internal cleaning of a container, in particular a liquid tank, wherein it only has to be brought into fluid communication with a source of cleaning liquid via a low-pressure hose. Such low pressure hoses have a higher flexibility as high-pressure hoses, as they are usually used to connect known cleaning heads to a stationary pressure pump.

During the orbital movement of the rotor housing of the displaceably mounted in the spray arm piston is driven due to the eccentricity of the eccentric to a reciprocating motion, so that during a suction stroke of the delivery piston cleaning fluid flow into the cylinder chamber and during a pressure stroke, the liquid pressurized from the cylinder and over the nozzle can be dispensed. The eccentric is held immobile relative to the rotor housing, while the rotor housing carries out a rotary movement together with the at least one spray arm fixed to it. Thus, the rotational movement of the rotor housing and the spray arm not only serves to generate a circulating on a circular path liquid jet, but it also serves to drive the displaceably mounted in the spray arm delivery piston.

It is advantageous if the cleaning fluid through the eccentric and the piston through the cylinder chamber can be fed. This allows a particularly compact design of the cleaning head. The eccentric not only assumes the function of a cam for controlling the movement of the delivery piston, but it also forms a channel for supplying the Reinigungsfüssigkeit in the cylinder chamber.

In a particularly preferred embodiment, the eccentric comprises a radially extending flow channel, which extends in the circumferential direction of the eccentric only over a partial region of the eccentric. The supply of the cleaning liquid through the piston to the cylinder chamber takes place over the flow channel of the eccentric. During the circulating movement of the rotor housing with the at least one spray arm, cleaning liquid is supplied non-uniformly to the cylinder chamber, namely only when there is a flow connection between the cylinder chamber and the flow channel. This flow connection consists only along a portion of the circumference of the eccentric, while in the remaining peripheral region, the flow connection between the flow channel and cylinder space is interrupted. Such a configuration is particularly advantageous when the delivery piston forms a suction stroke with an existing flow connection between the flow channel and the cylinder space and a pressure stroke when the flow connection between the cylinder space and the flow channel is interrupted. Additional control valves for the pressure pump can be omitted.

It is favorable if the flow channel extends in the circumferential direction of the eccentric over an angular range of at least 90 °.

In a particularly preferred embodiment, it is provided that the flow channel extends in the circumferential direction of the eccentric over an angular range of more than 180 °, in particular it can be provided that extends the flow channel in the circumferential direction of the eccentric over an angular range of about 220 °. Such a configuration has the advantage that the flow connection between the flow channel and the cylinder space is not only present when the piston performs a suction stroke for introducing cleaning liquid into the cylinder chamber, but also during a portion of its pressure stroke. As a result, the delivery of pressurized cleaning fluid through the nozzle to an angular range of less than 180 °, in particular an angular range of approximately 140 °. Such a configuration is particularly advantageous if the cleaning head comprises a plurality of spray arms each fixed to the rotating rotor housing, on each of which at least one nozzle is held. Cleaning liquid can be dispensed successively via the nozzles by means of the flow connection between the flow channel and the respective cylinder chamber, which exists only over a partial region of the circumference of the eccentric. By means of suitable alignment of the nozzles, a surface to be cleaned can be subjected to a strip of cleaning liquid jet in the form of a strip, wherein the distance between the respective nozzle delivering the cleaning liquid and the surface to be cleaned can be kept very small. Thus, an intensive cleaning liquid jet can be directed onto the surface.

The supply of cleaning fluid to the eccentric takes place in a preferred embodiment of a hollow shaft on which the eccentric is held against rotation. The hollow shaft serves for a storage of the eccentric and on the other hand it forms a supply line, via which the cleaning liquid can be supplied to the eccentric.

The reciprocating movement of the spray piston displaceably mounted in the delivery piston can be achieved that it lies with its end facing away from the cylinder chamber directly on the eccentric. However, this leads to a considerable frictional force between the delivery piston and eccentric. It is therefore advantageous if the delivery piston is mounted on a sliding shoe, which bears against the outer wall of the eccentric. This makes it possible to optimally adapt the sliding shoe and the delivery piston to the respectively prevailing requirements; in particular, the shape of the sliding shoe can be adapted to the shape be adapted to the eccentric and by suitable choice of material as low as possible friction between eccentric and shoe can be achieved.

Preferably, the sliding block has a through bore, via which the flow channel of the eccentric can be brought into fluid communication with a recess of the piston. The supply of cleaning fluid can thus be carried out through the eccentric and the shoe through to the delivery piston and from this through the recess to the cylinder chamber. Preferably, the recess of the piston is designed as a longitudinal bore, which is guided in the longitudinal direction of the piston through this.

It is advantageous if the delivery piston and the sliding block are pivotable relative to each other. This has the advantage that, with the radial orientation of the delivery piston remaining the same with respect to the axis of rotation of the rotor housing, the sliding block can follow the eccentric peripheral surface of the eccentric, without this leading to jamming of the piston or of the sliding shoe.

It may, for example, be provided that the sliding shoe and the delivery piston abut one another via a spherical recess and a spherical protrusion dipping into the recess. The recess and the corresponding projection allow a relative pivoting movement of the two parts while maintaining a planar contact.

It can be provided that the sliding shoe has on its side facing the delivery piston the spherical projection and the delivery piston having a ball-shaped recess arranged at its rear end takes the lead. Alternatively it can be provided that the end portion of the piston facing the sliding shoe forms the spherical projection, which dips into a spherical recess of the sliding shoe.

It has proved to be particularly advantageous if the sliding shoe has a recess in the region of its contact surface resting against the eccentric, to which the through bore of the sliding shoe adjoins in the direction of the delivery piston. During a suction stroke, a pressure is generated by the delivery piston within the cylinder space, which can spread through the recess of the piston and the through hole of the sliding thrust through into the recess of the sliding shoe. Within the contact area of the sliding shoe on the eccentric thus an overpressure is generated, which significantly reduces the frictional force between the eccentric and shoe. Outside the region of the depression, the overpressure in the contact region of the sliding shoe on the eccentric drops substantially linearly.

To generate the reciprocating movement of the delivery piston is provided in a structurally particularly simple embodiment, that the delivery piston is biased by a return spring in the direction of the eccentric.

It is advantageous if the return spring is disposed within the cylinder chamber.

The return spring can be clamped between the piston and a nozzle holder, for example, on which the at least one nozzle is held. In order to seal the cylinder space, it is advantageous if the piston is surrounded in the circumferential direction by at least one sealing ring.

Advantageously, the sealing ring is designed as a piston ring. It has been shown that this allows a particularly low-friction storage of the delivery piston in the spray arm while ensuring a high density between the delivery piston and the surrounding wall of the spray arm.

Preferably, the sealing ring, in particular the piston ring, made of a plastic material based on PEEK, that is based on a polyether ether ketone material.

The piston is made in a preferred embodiment of a light metal, such as an aluminum alloy, or of a plastic material.

It is advantageous if flow guide elements are arranged within the longitudinal bore of the piston, for example, cross-shaped webs, with the aid of which the flow can be aligned within the delivery piston.

The rotor housing is preferably mounted on a shaft and sealed with respect to this by means of at least one sealing ring. It is advantageous if the at least one sealing ring is designed as a piston ring.

The rotary drive of the rotor housing is preferably carried out by means of a drive motor which can be coupled via gear elements with the rotor housing. So Q

For example, an angle gear can be used or a belt drive.

It is particularly advantageous if the housing is rigidly connected to the rotor of an external rotor motor. This allows a particularly compact design of the cleaning head with connected electric drive.

It is advantageous if the cleaning head has a splash guard, in which the rotor housing is rotatably mounted and which has a liquid discharge opening. Such an embodiment of the cleaning head is particularly advantageous when used in a surface cleaning device for floor cleaning, because by means of splash guard is ensured in a structurally simple manner that the at least one, together with the rotor housing rotating nozzle surface to be cleaned only in the liquid discharge opening with cleaning liquid applied.

Preferably, a shaft is rotatably held on the splash guard on which the rotor housing is rotatably mounted.

As already explained, the cleaning head explained above is used in particular in a surface cleaning device. Here, in a preferred embodiment, it is provided that the surface cleaning device comprises a handle on which the cleaning head is held. Such a configuration has the advantage that the user can move the cleaning head with the help of the handle along a surface to be cleaned along, where he can assume an upright position. The surface cleaning device is thus stalk-shaped in the manner of a Stielstaubsaugers. It is advantageous if the surface cleaning device has support means for supporting the surface cleaning device on the surface to be cleaned. The user is thereby relieved of the weight of the surface cleaning device, in particular the weight of the cleaning head. This allows a particularly simple handling of the surface cleaning device.

The cleaning head is preferably arranged in the region of the end of the handle facing the surface to be cleaned, so that the center of gravity of the surface cleaning device is adjacent to the surface to be cleaned.

Preferably, the surface cleaning device comprises a manually operable switching member for controlling the liquid discharge of the cleaning head. It is advantageous if the switching element is arranged in the region of the cleaning head facing away from the end of the stem. The handling of the surface cleaning device can be further simplified.

A particularly compact design can be achieved in a surface cleaning device according to the invention in that the handle forms a supply line for cleaning agent, wherein the supply line to a supply hose can be connected. It can be provided that in the region of the end facing away from the cleaning head of the stem, a connection fitting is arranged for connection of the supply hose.

The following description of a preferred embodiment of a cleaning head according to the invention and an areal surface according to the invention nigungsgerätes used in conjunction with the drawings for further explanation. Show it:

Figure 1 is a schematic, partially sectioned front view of a surface cleaning device according to the invention;

Figure 2 is a fragmentary side view of the surface cleaning device of Figure 1;

Figure 3 is a schematic, partially sectioned front view of a cleaning head according to the invention of the surface cleaning device of Figure 1;

Figure 4 is a schematic partial sectional view taken along line 4-4 in Figure 3 and

Figure 5: a schematic partial sectional view corresponding to Figure 4 of an alternative embodiment of a cleaning head according to the invention.

In Figure 1, an inventive surface cleaning device 10 is shown schematically, which is designed as a hand-held, stalk-shaped pressure washer and can be moved by the user to clean a surface 11 along this. It comprises a handle 12, which is of tubular design and forms a supply line 13 for cleaning fluid, preferably water, which can be supplied to a cleaning head 15 which is fixed to the lower end of the handle 12 facing the surface 11 to be cleaned. is laid. The cleaning head 15, which is explained in more detail below with reference to Figures 3 and 4, has a splash guard 17, which faces the surface 11 defines a liquid discharge opening 19 which is circumferentially surrounded by a splash guard in the form of a bristle strip 21, the Surface 11 contacted. On the outside of the spray guard 17 of the liquid discharge opening 19 adjacent two freely rotatable about a common axis of rotation 23 support rollers 24, 25 are mounted, with the help of the surface cleaning device 10 can be supported on the surface 11 to be cleaned and moved along this.

Above the splash guard 17, an electric motor 27 is fixed to the handle 12, the housing 28 can be flowed around for cooling of cleaning fluid and is in operative connection with a rotatably mounted in the splash guard 17 about a rotational axis 29 rotor housing 30.

At its upper, the cleaning head 15 end facing away from the handle 12 carries a manually operable by the user switching member 33 with a pivot lever 34 and a connection fitting 35th

As is clear in particular from FIG. 2, the switching element 33 is designed in the manner of a pistol and comprises a handle 37 which can be gripped by the user and on which the pivot lever 34 is pivotably mounted. The switching device forms a check valve with which the flow of cleaning fluid can be selectively released and interrupted by the user. The connection fitting 35 is fixed to the end of the switching element 33 facing away from the handle 12 and serves to connect a low-pressure supply hose, via which the cleaning fluid can be supplied to the surface cleaning device 10.

On the stem 12, two hook-shaped holder 38, 39 are fixed at a distance to each other around which an electric supply cable for the electric motor 27 can be wound when the surface cleaning device 10 is not in operation.

The cleaning head 15, whose application is not limited to the stem-shaped surface cleaning device 10, which is explained for the sake of illustration on the example of the surface cleaning device 10, has three hollow cylindrical spray arms 41, 42, 43 which are fixed at a uniform angular distance from each other on the rotor housing 30 and At their free end, the spray arms 41, 42 and 43 each have a sleeve-shaped nozzle holder 45, which in the embodiment shown in Figures 1 to 4 of the cleaning head 15 in the spray arm 41, 42 and 43 is inserted and secured with transverse pins 47 and pressed in the embodiment according to Figure 5 on the spray arm 41, 42 and 43 and which protrudes with an end portion of the spray arm. The nozzle holder 45 receives a nozzle 46.

Apart from the region of the nozzle holder 45, the spray arms 41, 42 and 43 of the embodiment shown in Figures 1 to 4 are each lined by a sliding sleeve 49 which receives a displaceable in the longitudinal direction of the respective spray arm 41, 42, 43 feed piston 50, which in order - In the case of the alternative embodiment shown in FIG. 5, the delivery piston 50 rests, via the piston ring 52, directly against the inner wall of the respective spray arm 41, 42 and 43, respectively.

The nozzle 46 remote from the end portion of the delivery piston 50 is configured in the form of a spherical projection 54 which bears flat against a spherical recess 56 of a shoe 57. The sliding shoe 57 bears with a support surface 59 facing away from the delivery piston 50 against a non-rotatable eccentric 60 which is surrounded by the rotor housing 30. By rotating the rotor housing 30 and the spray arms 41, 42 and 43 fixed to it, the sliding shoes 57 can slide along the peripheral surface 61 of the eccentric 60. This is designed circular cylindrical, with its central axis 62 is arranged offset from the axis of rotation 29 of the rotor housing 30.

The eccentric 60 is rotatably held on a hollow shaft 64 which is rotatably held on an end wall 65 and a rear wall 66 of the splash guard 17, wherein it protrudes with its rear end 68 outwardly beyond the rear wall 66. Starting from the rear end 68 extends within the hollow shaft 64 up to the height of the eccentric 60, an axial bore 69, to which at the height of the eccentric 60, a continuous radial bore 70 connects.

The radial bore 70 opens into a radially extending flow channel 72 of the eccentric 60. The flow channel 72 extends in the circumferential direction of the eccentric 60 preferably over an angular range of more than 180 °, in the illustrated embodiment, it extends over an angular range from about 220 °. It opens into the peripheral surface 61 and forms a flow connection between the interior of the hollow shaft 64 and a through hole 74 of the sliding shoes 57, to which in the direction of the respective nozzle 46 a longitudinal bore 76 of the respective spray arm 41, 42 and 43 slidably mounted delivery piston 50th followed.

The sliding shoes 57 have in the region of their contact surface 59 each have a recess 78, to which the through hole 74 connects in the direction of the delivery piston 50.

The delivery pistons 50 are acted upon by a return spring 80 with an elastic restoring force in the direction of the respective sliding shoe 57, so that the sliding shoe 57 is pressed against the peripheral surface 61 of the eccentric 60. The return spring 80 is clamped between the respective delivery piston 50 and the nozzle holder 45. In the amount of the return spring 80, the spray arms 41, 42 and 43 define in the region between the respective delivery piston 50 and the nozzle holder 45, a cylinder chamber 82 into which the longitudinal bore 76 of the delivery piston 50 opens and via the sleeve-shaped nozzle holder 45 with the respective nozzle 46 in Flow connection is.

Via the hollow shaft 64, the eccentric 60, the sliding shoes 57 and the delivery piston 50, the cylinder chambers 82 of the spray arms 41, 42 and 43 cleaning liquid can be supplied. If the rotor housing 30 is rotated about the axis of rotation 29, the sliding shoes 57 slide along the peripheral surface 61 of the eccentric 60 and the spring piston 50 biased in the direction of the eccentric 60 lead due to the eccentric arrangement of the eccentric 60 relative to the axis of rotation 29 a There and Herbewegung within the respective spray arm 41, 42 and 43, so that within the cylinder chamber 82 cleaning fluid can be pressurized and then discharged through the nozzle 46. The supply of cleaning liquid to the cylinder chamber 82 takes place during a rotational movement of the rotor housing 30 only along the portion of the circumference of the eccentric 60, in which the flow channel 72 opens, while in the flow channel 72 is not detected peripheral region, the flow connection between the hollow shaft 64 and the cylinder chamber 82nd is interrupted. The flow channel 72 is arranged such that the delivery pistons 50 in the peripheral region of the eccentric 60 not detected by the flow channel 72 perform a lifting movement in the direction of the respective nozzle 46, the nozzle 46 facing the liquid discharge opening 19 and thus the surface 11 to be cleaned. Since the flow channel 72 extends in the circumferential direction of the eccentric 60 over an angular range of 220 °, whereas the entire lifting movement of the delivery piston over an angular range of 180 °, is still during the lifting movement of the respective delivery piston 50, the flow connection between the hollow shaft 64 and the cylinder chamber 82 released again. This has the consequence that during the lifting movement of the delivery piston 50, a pressure equalization between the cylinder chamber 82 and the hollow shaft 64 takes place, so that the delivery of pressurized cleaning fluid is interrupted via the nozzle 46. In this way, it is ensured that practically only pressurized cleaning fluid is discharged via the nozzles 46 when they face the liquid discharge opening 19.

By means of the nozzles 46, the surface to be cleaned can thus be successively applied in strip form with cleaning liquid, whereby the cleaning agent In each case, the dispensing nozzle 46 has a small distance from the surface 11, so that an intensive cleaning agent jet can be directed onto the surface 11.

The supply of cleaning liquid to the rear end 68 of the hollow shaft 64 is carried out starting from the supply line 13 via a not shown in the drawing, known per se flexible connecting line, which can be connected to the rear end 68.

The rotor housing 30 is rotated by the electric motor 27. The power transmission can take place, for example, with the aid of a gear mechanism 86, shown schematically in FIG. 4, which is designed as an angle gear and has a gear wheel 88 held in a rotationally fixed manner on a motor shaft 87, which meshes with a toothed ring 89, which is held against rotation on a bottom wall 91 of the rotor housing 30 is.

Instead of the toothed gear 86, for example, a belt drive known per se and therefore not shown in the drawing can be used.

As shown in Figure 5 as an alternative embodiment of the cleaning head 15, the electric motor 27 may be configured in the form of an external rotor motor 94 with a rotatably held on the hollow shaft 64 stator 95 which is surrounded by a rotor 96, wherein the rotor 96 rotatably on the Bottom wall 91 of the rotor housing 30 is held. This allows a particularly compact design, wherein the use of a transmission can be omitted.

Claims

PATENT CLAIMS

1. cleaning head for applying a surface to be cleaned with cleaning fluid under pressure with at least one spray arm, which is rotatably mounted about a rotation axis and on which is held at least one nozzle which is supplied from a pressure pump cleaning liquid, characterized in that the pressure pump in the cleaning head (15) is integrated.

2. Cleaning head according to claim 1, characterized in that the cleaning head (15) has a rotor housing (30) which surrounds an eccentric (60) and with respect to the eccentric (60) about the axis of rotation (29) is rotatable, wherein on the rotor housing ( 30) at least one spray arm (41, 42, 43) is fixed and in the spray arm (41, 42, 43) a delivery piston (50) is displaceably mounted, according to the orbital movement of the rotor housing (30) about the eccentric (60) within the Spray arm (41, 42, 43) is drivable for reciprocation, wherein the delivery piston (50) in a cylinder chamber (82) is immersed, which is in fluid communication with the at least one nozzle (46) and the cleaning fluid can be supplied.

3. Cleaning head according to claim 2, characterized in that the cleaning liquid through the eccentric (60) and the delivery piston (50) through the cylinder chamber (82) can be fed.

4. Cleaning head according to claim 3, characterized in that the eccentric (60) comprises a radially extending flow channel (72) which extends in the circumferential direction of the eccentric (60) only over a partial region of the eccentric (60).

5. Cleaning head according to claim 4, characterized in that extending the flow channel (72) in the circumferential direction of the eccentric (60) over an angular range of at least 90 °.

6. Cleaning head according to claim 4 or 5, characterized in that the flow channel (72) extends in the circumferential direction of the eccentric (60) over an angular range of more than 180 °.

7. Cleaning head according to one of claims 3 to 6, characterized in that the eccentric (60) rotationally fixed to a hollow shaft (64) is held, via which the cleaning liquid to the eccentric (60) can be fed.

8. Cleaning head according to one of claims 2 to 7, characterized in that the delivery piston (50) in a sliding shoe (57) is mounted, which bears against a peripheral surface (61) of the eccentric (60).

9. Cleaning head according to claim 8, characterized in that the sliding shoe (57) has a through bore (74) via which the flow channel (72) of the eccentric (60) with a recess (76) of the delivery piston (50) can be brought into flow communication ,

10. Cleaning head according to claim 9, characterized in that the recess of the delivery piston (50) is designed as a longitudinal bore (76).

11. Cleaning head according to one of claims 8 to 10, characterized in that the sliding shoe (57) and the delivery piston (50) via a spherical recess (56) and in the recess (56) dipping spherical projection (54) abut each other.

12. Cleaning head according to claim 11, characterized in that the sliding shoe (57) facing the end region of the delivery piston (50) forms the spherical projection (54) which dips into a spherical recess (56) of the sliding shoe (57).

13. Cleaning head according to one of claims 8 to 12, characterized in that the sliding shoe (57) in the region of its on the eccentric (60) abutting bearing surface (59) has a recess (78) to which in the direction of the delivery piston (50) the through hole (74) connects.

14. Cleaning head according to one of claims 2 to 13, characterized in that the delivery piston (50) by means of a return spring (80) is biased in the direction of the eccentric (60).

15. Cleaning head according to claim 14, characterized in that the return spring (80) in the cylinder chamber (82) is arranged.

16. Cleaning head according to claim 14 or 15, characterized in that the return spring (80) between the delivery piston (50) and a nozzle holder (45) is clamped, on which the at least one nozzle (46) is held.

17. Cleaning head according to one of claims 2 to 16, characterized in that the delivery piston (50) in the circumferential direction of at least one sealing ring (52) is surrounded.

18. Cleaning head according to claim 17, characterized in that the sealing ring is designed as a piston ring (52).

19. Cleaning head according to claim 17 or 18, characterized in that the sealing ring (52) is made of a plastic material based on PEEK.

20. Cleaning head according to one of claims 2 to 19, characterized in that the delivery piston (50) is made of a light metal or a plastic material.

21. Cleaning head according to one of claims 2 to 20, characterized in that the rotor housing (30) is rotatably mounted on a shaft (64) and sealed against this by means of at least one sealing ring.

22. Cleaning head according to claim 21, characterized in that the at least one sealing ring is designed as a piston ring.

23. Cleaning head according to one of claims 2 to 22, characterized in that the rotor housing (30) via transmission elements (86) with a drive motor (27) can be coupled.

24. Cleaning head according to one of claims 2 to 22, characterized in that the rotor housing (30) is rigidly connected to the rotor (96) of an external rotor motor (94).

25. Cleaning head according to one of claims 2 to 24, characterized in that the cleaning head (15) has a splash guard (17) in which the rotor housing (30) is rotatably mounted and which has a liquid discharge opening (19).

26. Cleaning head according to claim 25, characterized in that on the splash guard (17) a shaft (64) is rotatably held, on which the rotor housing (30) is rotatably mounted.

27. surface cleaning device with a cleaning head (15) according to any one of the preceding claims.

28. surface cleaning device according to claim 27, characterized in that the surface cleaning device (10) comprises a handle (12) on which the cleaning head (15) is held.

29. Surface cleaning device according to claim 27 or 28, characterized in that the surface cleaning device (10) supporting means (24, 25) for supporting the surface cleaning device (10) on the surface to be cleaned (11).

30. surface cleaning device according to claim 27, 28 or 29, characterized in that the surface cleaning device (10) comprises a manually operable switching member (33) for controlling the liquid discharge of the cleaning head (15).

31. Surface cleaning device according to claim 30, characterized in that the switching element (33) is held on the cleaning head (15) facing away from the end of the stem (12).

32. Surface cleaning device according to one of claims 27 to 31, characterized in that the handle (12) forms a supply line (13) for cleaning agent, wherein the supply line (13) is connectable to a supply hose.