Surface cleaning head

Abstract

The present invention relates to a surface cleaning head, which is used for cleaning a surface and comprises a housing having a cleaning space surrounded by a peripheral wall, wherein at least one spray arm is supported in the cleaning space in a manner that it can rotate freely around a rotation axis, and a cleaning nozzle is held on the spray arm for applying a pressurized cleaning liquid to the surface, and the surface cleaning head also comprises a jet pump, which is used to suck out the cleaning liquid applied to the surface, wherein the jet pump has a suction socket in fluid connection with the cleaning space, the suction socket is connected to the peripheral wall and can be connected to an outlet line, wherein a drive nozzle that can be loaded with pressurized cleaning liquid for forming a suction flow is arranged in the suction socket. In order to achieve good suction removal with less consumption of cleaning liquid, the drive nozzle is designed as a full cone nozzle, and its nozzle characteristic parameter is 0.18 l / min to 0.35 l / min when the reference pressure is 1 bar.

Description

Technical Field

[0001] The present invention relates to a surface cleaning head for cleaning surfaces, the surface cleaning head comprising a shell having a cleaning space surrounded by a peripheral wall and open downwardly when the surface cleaning head is in a horizontal use state, wherein at least one spray arm is supported in the cleaning space in a manner that allows it to rotate freely around a rotation axis, wherein a cleaning nozzle that can be loaded with a pressurized cleaning liquid is retained on the spray arm for applying the cleaning liquid to the surface to be cleaned, and the surface cleaning head further comprises a jet pump that is used to absorb the cleaning liquid that has been applied to the surface to be cleaned, wherein the jet pump has a suction socket that is fluidly connected to the cleaning space, the suction socket is connected to the peripheral wall, and can be connected to an outlet line, wherein a drive nozzle that can be loaded with a pressurized cleaning liquid for forming a suction flow is arranged in the suction socket. Background Art

[0002] Such a surface cleaning head is known from EP 2 547 463 B1. A spray gun of a high-pressure cleaner can be connected to the surface cleaning head, so that the cleaning liquid pressurized by the high-pressure cleaner can be delivered to a cleaning nozzle held on a spray arm in the cleaning space. With the help of the cleaning nozzle, the cleaning liquid can be sprayed onto the surface to be cleaned. The cleaning nozzle produces a liquid jet oriented obliquely downward in the direction of the surface to be cleaned and is subjected to a recoil force, so that the spray arm rotates around the rotation axis together with the cleaning nozzle. Usually, at least two spray arms that are opposite to each other are used, and cleaning nozzles are respectively arranged on the spray arms, wherein the cleaning nozzles can be loaded with pressurized cleaning liquid at the same time.

[0003] In addition to at least one cleaning nozzle, the surface cleaning head known from EP 2 547 463 B1 also has a jet pump, which works according to the principle of a Venturi pump. It comprises a suction connection, in which a drive nozzle is positioned, which can also be loaded with pressurized cleaning liquid. By discharging the pressurized cleaning liquid, a suction flow can be generated inside the suction connection by means of the drive nozzle. The suction connection is in flow connection with the cleaning space of the surface cleaning head, so that the cleaning liquid applied to the surface can be sucked up together with the cleaned dirt under the effect of the suction flow. An outlet line can be connected to the free end of the suction connection, and the sucked cleaning liquid can be discharged via the outlet line together with the cleaned dirt.

[0004] In the surface cleaning head known from EP 2 547 463 B1, effective suction can be achieved, but it would be desirable to reduce the consumption of cleaning liquid required for suction. Summary of the invention

[0005] It is therefore an object of the present invention to improve a surface cleaning head of the type mentioned at the outset in such a way that it enables good suction with a low consumption of cleaning fluid.

[0006] This object is achieved according to the invention in a surface cleaning head of the generic type in that the drive nozzle is designed as a full cone nozzle, the characteristic nozzle variable of which is 0.18 l / min to 0.35 l / min at a reference pressure of 1 bar.

[0007] The surface cleaning head according to the present invention is characterized in particular by the use of a drive nozzle in the form of a full cone nozzle. This nozzle discharges a conical liquid jet, under the action of which a strong suction flow is formed inside the suction socket, so that the cleaning liquid applied to the surface to be cleaned and the cleaned dirt are sucked up together and can be discharged via the suction socket and the outlet line connected to the suction socket. Particularly good suction efficiency, that is, good suction removal is achieved under relatively low consumption of pressurized cleaning liquid by the following method, that is, when the reference pressure is 1 bar, the nozzle characteristic parameter of the full cone nozzle is 0.18l / min to 0.35l / min. The nozzle characteristic parameter is currently defined as the flow rate at a specific reference pressure, more precisely, the flow rate of the cleaning liquid flowing through the drive nozzle when the reference pressure is 1 bar is 0.18l / min to 0.35l / min.

[0008] A pressurized cleaning liquid can be delivered to the surface cleaning head by a high-pressure cleaner. A portion of the cleaning liquid provided is sprayed onto the surface to be cleaned, while the remaining portion of the cleaning liquid is used to form a suction flow so as to suck up the sprayed cleaning liquid and the cleaned dirt together. Using a driving nozzle in the form of a full-cone nozzle with a nozzle characteristic parameter of 0.18 l / min to 0.35 l / min at a reference pressure of 1 bar enables the cleaning liquid applied to the surface and the cleaned dirt to be effectively sucked away together with a relatively low consumption of pressurized cleaning liquid, so that a large portion of the cleaning liquid provided can be sprayed onto the surface to be cleaned. This allows the surface to be effectively cleaned and sucked with the help of the surface cleaning head.

[0009] The good suction removal of cleaning liquid applied to the surface to be cleaned and cleaned-off dirt that can be achieved with the surface cleaning head according to the invention allows dirty liquid to be discharged via the outlet line itself even if the outlet line overcomes a height difference of up to 0.8 m.

[0010] The pressure of the cleaning liquid supplied to the surface cleaning head may be, for example, 50 bar to 180 bar, in particular 70 bar to 120 bar.

[0011] The total consumption of cleaning liquid for cleaning and suction can be, for example, 200 l / h to 700 l / h.

[0012] It is particularly advantageous if the nozzle characteristic variable of the drive nozzle is 0.18 l / min to 0.28 l / min.

[0013] In a preferred embodiment of the surface cleaning head according to the present invention, the driving nozzle includes a nozzle cap, the nozzle cap having a nozzle outlet opening, the nozzle outlet opening being arranged at the tip of a conical end section of the inner space of the nozzle cap, wherein a nozzle insert is arranged in the conical end section, wherein the nozzle insert has a cylindrical base, a truncated cone-shaped protrusion connected to the base in the direction of the nozzle outlet opening, and its peripheral side surface is form-lockedly attached to the inner wall of the conical end section of the inner space of the nozzle cap, wherein the nozzle insert has a through-channel directed toward the nozzle outlet opening and a plurality of swirl channels formed in the peripheral side surfaces of the truncated cone-shaped protrusion, wherein the through-channel opens into a swirl chamber in the conical end section directly preceding the nozzle outlet opening, and wherein the swirl channel opens into the swirl chamber laterally offset from the through-channel.

[0014] In this design, the driving nozzle includes a nozzle cap, which has an inner space. The end section of the inner space is designed to be conical. At the tip of the conical end section, the nozzle cap has a nozzle outflow opening, and the pressurized cleaning liquid can be discharged from the driving nozzle via the nozzle outflow opening. The nozzle outflow opening extends into the conical end section of the inner space of the nozzle cap. The end section accommodates a nozzle plug-in, which has a cylindrical base and a truncated cone-shaped protrusion connected thereto. The peripheral side of the truncated cone-shaped protrusion is abutted against the inner wall of the conical end section in a shape-locking manner. The nozzle plug-in has a through-channel oriented to the nozzle outflow opening. In addition, the nozzle plug-in has a plurality of swirl channels, which are formed into the peripheral side of the truncated cone-shaped protrusion. Between the nozzle plug-in and the nozzle outflow opening, the conical end section of the inner space of the nozzle cap constitutes a swirl chamber. The through-channel of the nozzle plug-in passes into the swirl chamber centrally, and the swirl channel passes into the swirl chamber laterally with the through-channel staggered. This design of the drive nozzle makes it possible to discharge the cleaning fluid in the form of a full-cone jet, so that a strong suction flow is formed inside the suction connection downstream of the drive nozzle.

[0015] Preferably, the through-channel and the nozzle outflow opening are arranged colinearly with respect to a central axis of the drive nozzle.

[0016] Advantageously, 2, 3, 4, 5 or 6 swirl channels are formed into the circumference of the truncated-conical projection.

[0017] Preferably, the swirl channels are evenly distributed on the circumference of the truncated cone-shaped protrusion.

[0018] The swirl channel is preferably designed to be straight. This allows the manufacturing costs for the swirl channel to be kept very low.

[0019] In an advantageous embodiment of the invention, the longitudinal axis of the swirl channel is oriented skewed in an eccentric manner relative to the longitudinal axis of the through-channel.

[0020] Advantageously, the flow cross section of the nozzle outflow opening is at most one third of the sum of the flow cross sections of the through-channel and the swirl channel. In this design, the pressurized cleaning liquid can be supplied to the swirl chamber via a relatively large flow cross section, while the cleaning liquid can be discharged from the swirl chamber via a relatively small flow cross section. It has been shown that the suction efficiency of the jet pump can be improved in this way.

[0021] Preferably, the flow cross section of the nozzle outflow opening is at most as large as the flow cross section of the through-channel and at most half the sum of the flow cross sections of the swirl channels.

[0022] It is particularly advantageous if the flow cross section of the nozzle outflow opening is at most one fifth of the sum of the flow cross sections of the through-channel and the swirl channel.

[0023] Advantageously, the flow cross section of the nozzle outflow opening is smaller than the flow cross section of the through-channel and also smaller than the flow cross section of each individual swirl channel.

[0024] In a preferred embodiment of the present invention, the surface cleaning head has an inlet line for conveying a pressurized cleaning liquid, wherein a liquid distribution device is connected to the inlet line, the liquid distribution device is connected to the drive nozzle via a first branch line, and is connected to at least one cleaning nozzle via a second branch line, wherein the end area of ​​the first branch line facing away from the liquid distribution device extends into the suction socket and carries the drive nozzle. This design scheme enables the drive nozzle to be positioned inside the suction socket without having to support the drive nozzle on the suction socket via a supporting element. More precisely, in this design scheme, the drive nozzle is completely surrounded by an annular space in the circumferential direction, through which the cleaning liquid applied to the surface to be cleaned can flow into the suction socket together with the cleaned dirt. Therefore, the suction flow is only subject to very low flow losses in the area of ​​the drive nozzle.

[0025] Advantageously, the nozzle cap of the driving nozzle is held in a releasable and liquid-tight manner on the end region of the first branch line that extends into the suction connection, wherein the nozzle insert of the driving nozzle rests on one or more supporting surfaces of the first branch line. In this design, the nozzle insert rests with its base on one or more supporting surfaces of the first branch line and with the circumferential side surface of the truncated cone-shaped protrusion on the inner wall of the conical end section of the interior space of the nozzle cap. This allows the nozzle insert to be clamped between the inner wall of the end section and at least one supporting surface of the first branch line and thus mechanically fixed.

[0026] It is particularly advantageous if the nozzle cap is screwed to the end region of the first branch line that projects into the suction connection. In this embodiment, the nozzle cap can be screwed onto the end region of the first branch line, wherein the nozzle cap surrounds the nozzle insert which is supported on the one hand on the inner wall of the nozzle cap and on the other hand on one or more support surfaces of the first branch line.

[0027] Advantageously, a sealing element is arranged between the nozzle cap and the end region of the first branch line extending into the suction connection. For example, a sealing ring can be used as the sealing element, which can be positioned in an annular groove that surrounds the end region of the first branch line in the circumferential direction.

[0028] The first branch line establishes a flow connection between the liquid distribution device and the drive nozzle. Advantageously, the first branch line is connected to the liquid distribution device in a releasable manner. This allows a simple assembly of the first branch line and also enables the first branch line to be removed from the surface cleaning head together with the drive nozzle held thereon, so that the drive nozzle can be subsequently removed from the first branch line, for example for cleaning purposes or also for replacing the nozzle insert.

[0029] In a particularly preferred design of the surface cleaning head according to the present invention, the flow rate of the cleaning liquid that can be delivered to the drive nozzle via the first branch line is less than the flow rate of the cleaning liquid that can be delivered to at least one cleaning nozzle via the second branch line. Therefore, the amount of cleaning liquid discharged from the drive nozzle per unit time is less than the amount of cleaning liquid discharged via at least one cleaning nozzle. This allows for particularly effective cleaning of the surface, and at the same time ensures that the cleaning liquid applied to the surface to be cleaned can be sucked away together with the cleaned dirt through the high suction efficiency of the jet pump.

[0030] The flow rate of the cleaning fluid which can be delivered to the drive nozzle via the first branch line is preferably at most 50% of the flow rate of the cleaning fluid which can be delivered to the at least one cleaning nozzle via the second branch line.

[0031] In order to prevent dirt particles carried by the cleaning fluid from clogging the drive nozzle over time, it is advantageous if a filter device is arranged in the flow path of the pressurized cleaning fluid upstream of the nozzle insert of the drive nozzle. The filter device can hold back dirt particles so that they cannot damage the drive nozzle.

[0032] It is particularly advantageous if the filter device has a convexly curved filter surface. The convex curvature makes it possible to provide a relatively large filter surface without requiring a large installation space for the filter device.

[0033] It can be provided that the filter device has a cup-shaped or bell-shaped filter surface.

[0034] Preferably, the filter device has a sieve. The mesh width of the sieve is preferably at most 0.6 mm, in particular at most 0.3 mm.

[0035] The screen preferably consists of metal, in particular steel, and / or a plastic material.

[0036] Advantageously, the filter device is arranged directly upstream of the nozzle insert.

[0037] For example, it can be provided that the filter is arranged upstream of the nozzle insert in the inner space of the nozzle cap of the driving nozzle. In this design, the driving nozzle and the filter constitute a structural assembly in combination, which is positioned in the end region of the first branch line extending into the suction socket.

[0038] Advantageously, the filter device is arranged between the end face of the first branch line facing the nozzle insert driving the nozzle and the base of the nozzle insert. In particular, it can be provided that the filter device is clamped between the end face of the first branch line and the base of the nozzle insert.

[0039] The drive nozzle is arranged in the suction connection socket of the jet pump of the surface cleaning head. Preferably, the suction connection socket forms an inlet channel, which is connected to a mixing channel, and the mixing channel tapers conically in the flow direction of the cleaning liquid.

[0040] Advantageously, a collecting channel is connected to the mixing channel, via which the mixing channel is connected to the diffuser.

[0041] The collecting channel is preferably designed in the form of a cylinder.

[0042] The diameter of the collecting channel is preferably at least 20 mm, in particular 20 mm to 25 mm, for example 23 mm.

[0043] The distance between the drive nozzle and the collecting channel is preferably a maximum of 40 mm.

[0044] It is particularly advantageous if the full cone jet emerging from the drive nozzle widens continuously within the mixing channel over the entire length of the mixing channel.

[0045] In an advantageous embodiment of the invention, the diameter of the nozzle outflow opening of the drive nozzle is approximately 0.7 mm.

[0046] The diameter of the through-channel of the nozzle insert of the drive nozzle is preferably approximately 0.8 mm.

[0047] The flow cross section of the swirl channels is preferably approximately 0.6 mm 2 Up to 0.7mm 2 . BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The following description of the preferred embodiments of the present invention in conjunction with the accompanying drawings is used for a more detailed explanation.

[0049] Figure 1 : shows a perspective view of a surface cleaning head with an outlet line coupled thereto;

[0050] Figure 2 : Show Figure 1 A longitudinal cross-sectional view of a surface cleaning head having an outlet line connected thereto;

[0051] Figure 3 : A perspective view showing a first branch circuit of a surface cleaning head, the branch circuit carrying a drive nozzle;

[0052] Figure 4 : Show Figure 3 A perspective view of a first branch line of the invention, wherein a nozzle cap of the driving nozzle is hidden;

[0053] Figure 5 : Show Figure 2 A magnified view of the detail Z;

[0054] Figure 6 : A perspective view of the nozzle insert showing the driving nozzle. DETAILED DESCRIPTION

[0055] An advantageous embodiment of a surface cleaning head according to the invention is schematically shown in the drawing in a horizontal position of use and is designated overall by reference numeral 10. With the aid of the surface cleaning head 10, a surface 12 to be cleaned can be loaded with pressurized cleaning liquid in order to clean the surface 12, and the cleaning liquid applied to the surface 12 can be sucked up together with the cleaned dirt and discharged via an outlet line 14.

[0056] The surface cleaning head 10 has a hood-shaped housing 16 on which three support wheels 18, 20, 22 are rotatably mounted. With the support wheels 18, 20, 22, the surface cleaning head 10 can be moved along the surface 12 to be cleaned.

[0057] The housing 16 has an intermediate wall 24, to which a cylindrical peripheral wall 26 is connected downwardly in the direction of the surface 12 to be cleaned. The peripheral wall 26 surrounds a cleaning space 28 and carries a surrounding splash guard element 30 on its edge facing the surface 12 to be cleaned, which is designed in the form of a brush strip in the illustrated embodiment.

[0058] Above the intermediate wall 24, the housing 16 defines a distribution space 32, which accommodates a liquid distribution device 34. Into the distribution space 32 extends an inlet line 36, which is connected to the liquid distribution device 34 and carries a coupling element 38 at its end facing away from the liquid distribution device 34, to which a spray gun of a high-pressure cleaner, which is known per se and is therefore not shown in the drawings for the sake of a better overview, can be coupled. With the aid of a high-pressure cleaner, a cleaning liquid, preferably water, can be pressurized in a known manner, which cleaning liquid can be supplied to the surface cleaning head via the spray gun.

[0059] The pressure of the cleaning liquid can be, for example, 50 bar to 180 bar, in particular 70 bar to 120 bar.

[0060] The flow rate of cleaning fluid delivered to the surface cleaning head 10 is preferably from about 200 1 / h to about 700 1 / h.

[0061] The peripheral wall 26 has a lateral recess 40 , to which a suction connection 42 of a jet pump 44 , which will be explained in greater detail below, is connected.

[0062] The suction connection 42 forms an inlet channel 46 connected directly to the lateral notch 40, which is connected to a cylindrical collecting channel 50 via a mixing channel 48 tapering in a direction away from the inlet channel 46, and to which a diffuser 52 is connected. The collecting channel 50 is cylindrical in design, and the diffuser 52 widens conically in a direction away from the collecting channel 50. The outlet line 14 can be connected to the diffuser 52. If necessary, the outlet line 14 can be separated from the diffuser 52.

[0063] The cleaning liquid delivered to the surface cleaning head 10 via the inlet line 36 is divided by the fluid distribution device 34, wherein a first part of the cleaning liquid is delivered to a drive nozzle 56 of a jet pump 44 arranged in an inlet channel 46 of a suction socket 42 via a first branch line 54, and wherein a second part of the cleaning liquid is delivered to a cleaning nozzle assembly 60 arranged in a cleaning space via a second branch line 58.

[0064] The cleaning nozzle assembly 60 has a first cleaning nozzle 62 and a second cleaning nozzle 64. The first cleaning nozzle 62 is arranged on a first spray arm 66, and the second cleaning nozzle 64 is arranged on a second spray arm 68. The two spray arms 66, 68 are opposite to each other and are supported on the second branch line 58 in a manner that they can rotate freely around an axis of rotation 70 perpendicular to the surface 12 to be cleaned. Pressurized cleaning liquid can be sprayed onto the surface 12 to be cleaned via the first cleaning nozzle 62 and the second cleaning nozzle 64. The cleaning nozzles 62, 64 are subjected to a recoil force, under the action of which the spray arms 66, 68 rotate around the axis of rotation 70.

[0065] The first branch line 54 can be releasably connected to the liquid distribution device 34 by means of a connecting element 72 formed at the end of the first branch line 54 facing the liquid distribution device 34. In addition, a holding arm 74 pointing obliquely upward is formed approximately in the middle of the first branch line 54, by means of which the first branch line 54 can be releasably held on the intermediate wall 24.

[0066] The first branch line 34 is sunk into the suction connection 42 with an end region 76 facing away from the liquid distribution device 34. The drive nozzle 56 is detachably held at this end region 76.

[0067] The driving nozzle 56 is designed as a full cone nozzle. Figure 5 It can be seen that the drive nozzle 56 has a nozzle cap 78 , whose interior space 80 accommodates the end region 76 of the first branch line 54 , wherein the nozzle cap 78 has an internal thread 82 which can be detachably screwed to a complementary external thread 84 of the end region 76 .

[0068] In order to ensure a fluid-tight connection between the end region 76 and the nozzle cap 78 , a sealing element in the form of a sealing ring 86 is used which is arranged in an annular groove 88 in the end region 76 .

[0069] The interior space 80 of the nozzle cap 78 has a conical end section 90, at the tip of which a nozzle outflow opening 92 is arranged. A nozzle insert 94 is arranged in the conical end section 90, which has a cylindrical base 96, to which a truncated cone-shaped projection 98 adjoins in the direction of the nozzle outflow opening 92.

[0070] The nozzle insert 94 is penetrated by a through passage 100 that is directed toward the nozzle outlet opening 92. The nozzle outlet opening 92 and the through passage 100 are oriented co-linearly with a central axis 102 of the drive nozzle 56.

[0071] The truncated cone-shaped projection 98 of the nozzle insert 94 has a circumferential surface 104, which bears in a form-fitting manner against an inner wall 106 of the conical end section 90. Four identical, respectively rectilinear swirl channels 108 are formed in the circumferential surface 104 and are arranged evenly distributed around the circumference of the truncated cone-shaped projection 98. The longitudinal axis 109 of the swirl channels 108 is oriented skewedly eccentrically with respect to the longitudinal axis 101 of the through-channel 100.

[0072] The flow cross section of the swirl channel 108 is larger than the flow cross section of the nozzle outflow opening 92. Preferably, the flow cross section of the swirl channel is also larger than the flow cross section of the through-channel 100.

[0073] In the preferred embodiment shown, the swirl channel 108 has a U-shaped cross section.

[0074] The nozzle outflow opening 92 has a circular cross section, and the through-channel 100 also has a circular cross section. The through-channel 100 may have a diameter of, for example, 0.8 mm, and the nozzle outflow opening may have a diameter of, for example, 0.7 mm.

[0075] Between the nozzle insert 94 and the nozzle outflow opening 92 , the conical end section 90 forms a conical swirl chamber 110 , into which both the through-channel 100 and the swirl channel 108 open.

[0076] The through-channel 100 oriented in line with the central axis 102 opens into the swirl chamber 110 in the center, while the swirl channel 108 opens into the swirl chamber 110 laterally offset from the through-channel 100. Figure 6 Especially clear in.

[0077] The end region 76 of the first branch line 54 has at its free end three holding fingers 112, 113 and 114, which are arranged at regular angular intervals from one another and face the conical end section 90 of the interior space 80. A filter device 116 in the form of a sieve is arranged between the holding fingers 112, 113, 114 and is directly upstream of the nozzle insert 94. The nozzle insert 94 is supported on its back side facing the first branch line 54 on a support surface 118 of the holding fingers 112, 113, 114. The nozzle insert 94 is clamped between the support surface 118 and the inner wall 106 of the conical end section 90, and the sieve 116 is held in position between the holding fingers 112, 113, 114.

[0078] The sieve 116 is preferably made of metal, in particular steel and / or plastic material. The mesh width of the sieve 116 is at most 0.6 mm, and the mesh width of the sieve 116 is preferably at most 0.3 mm.

[0079] The screen 116 forms a filter surface or screen surface 120 through which a pressurized cleaning fluid can flow. Preferably, the filter surface 120 is designed in a cup-shaped or bell-shaped manner or is convexly curved.

[0080] As already mentioned, a pressurized cleaning liquid can be applied to the surface 12 to be cleaned by means of the cleaning nozzle assembly 60. The applied liquid can then be sucked up together with the cleaned dirt by means of the jet pump 44 and discharged via the suction connection 42 and the outlet line 14. For this purpose, the pressurized cleaning liquid can be conveyed to the drive nozzle 56 via the first branch line 54, wherein a part of the conveyed cleaning liquid flows through the through-channel 100 and another part of the conveyed cleaning liquid flows through the swirl channel 108. In this way, the cleaning liquid reaches the swirl chamber 110, from which it is discharged via the nozzle outflow opening 92 in the form of a full cone jet.

[0081] The flow cross section of nozzle outlet opening 92 is smaller than the flow cross section of through-channel 100 and also smaller than the flow cross section of swirl channel 108. The flow cross section of nozzle outlet opening 92 is at most one third, in particular one fifth, of the sum of the flow cross sections of through-channel 100 and swirl channel 108.

[0082] The flow rate of the cleaning liquid that can be delivered to the driving nozzle 56 via the first branch line 54 is less than the flow rate of the cleaning liquid that can be delivered to at least one cleaning nozzle 62, 64 via the second branch line 58. In the illustrated embodiment, the flow rate of the cleaning liquid that can be delivered to the driving nozzle 56 via the first branch line 54 is at most 50% of the flow rate of the cleaning liquid that can be delivered to the cleaning nozzles 62, 64 via the second branch line 58.

[0083] As already mentioned, the pressurized cleaning liquid is discharged in the form of a full cone jet from the drive nozzle 56. The drive nozzle 56 thus forms a full cone nozzle. The nozzle characteristic parameter of the drive nozzle 56 is 0.18 l / min to 0.35 l / min, in particular 0.18 l / min to 0.28 l / min at a reference pressure of 1 bar.

[0084] The jet pump 44 has a high suction efficiency, that is, it can realize a strong suction flow under the situation that the consumption of pressurized cleaning liquid is relatively small. About one-third of the cleaning liquid provided to the surface cleaning head 10 is used to generate the suction flow, and about two-thirds of the cleaning liquid provided to the surface cleaning head 10 is sprayed on the surface 12.

Claims

1. A surface cleaning head for cleaning a surface (12) and comprising a housing (16), the housing having a cleaning space (28) surrounded by a peripheral wall (26) and open downwardly in the use state of the surface cleaning head (10), wherein at least one spray arm (66, 68) is supported in the cleaning space in a manner that allows free rotation about a rotation axis (70), wherein: A cleaning nozzle (62, 64) capable of being loaded with a pressurized cleaning liquid is held on the spray arm (66, 68) for applying the cleaning liquid to the surface (12) to be cleaned, the surface cleaning head also comprising a jet pump (44) for sucking away the cleaning liquid applied to the surface (12) to be cleaned, wherein the jet pump (44) has a suction connection (42) in fluid connection with the cleaning space (28), the suction connection is connected to the peripheral wall (26) and can be connected to an outlet line (14), wherein a drive nozzle (56) capable of being loaded with a pressurized cleaning liquid for forming a suction flow is arranged in the suction connection (42), characterized in that the drive nozzle (56) is designed as a full cone nozzle, and at a reference pressure of 1 bar, the nozzle characteristic parameter of the drive nozzle is 0.18 l / min to 0.35 l / min, The drive nozzle (56) comprises a nozzle cap (78) having a nozzle outflow opening (92), wherein the nozzle outflow opening is arranged at the tip of a conical end section (90) of an inner space (80) of the nozzle cap (78), wherein a nozzle insert (94) is arranged in the conical end section (90), wherein the nozzle insert (94) has a cylindrical base, and a truncated cone-shaped protrusion (98) is connected to the base in the direction of the nozzle outflow opening (92), and the peripheral side surface (104) of the truncated cone-shaped protrusion is in a form-locking manner against the truncated cone-shaped protrusion. The nozzle insert (94) has a through-channel (100) directed toward a nozzle outflow opening (92) and a plurality of swirl channels (108) formed into the circumferential side (104) of the truncated cone-shaped protrusion (98), wherein the through-channel (100) opens into a swirl chamber (110) located directly in front of the nozzle outflow opening (92) in the conical end section (90), and wherein the swirl channels (108) open into the swirl chamber (110) laterally offset from the through-channel (100).

2. The surface cleaning head according to claim 1, characterized in that The swirl channels (108) are arranged uniformly distributed on the periphery of the truncated cone-shaped protrusion (98).

3. The surface cleaning head according to claim 1, characterized in that The swirl channel (108) is designed to be straight.

4. The surface cleaning head according to claim 3, characterized in that The longitudinal axis (109) of the swirl channel (108) is oriented skewed and eccentrically relative to the longitudinal axis of the through-channel (100).

5. The surface cleaning head according to claim 1, characterized in that The flow cross section of the nozzle outflow opening (92) is at most one third of the sum of the flow cross sections of the through-channel (100) and the swirl channel (108).

6. The surface cleaning head according to claim 5, characterized in that The flow cross section of the nozzle outflow opening (92) is at most as large as the flow cross section of the through-channel (100) and is at most half the sum of the flow cross sections of the swirl channels (108).

7. The surface cleaning head according to claim 5, characterized in that The flow cross section of the nozzle outflow opening (92) is smaller than the flow cross section of the through-channel (100) and smaller than the flow cross section of each individual swirl channel (108).

8. A surface cleaning head according to any one of claims 1 to 7, characterised in that The surface cleaning head (10) has an inlet line (36) for conveying pressurized cleaning liquid, wherein a liquid distribution device (34) is connected to the inlet line (36), and the liquid distribution device is connected to the drive nozzle (56) via a first branch line (54) and connected to the at least one cleaning nozzle (62, 64) via a second branch line (58), wherein an end region (76) of the first branch line (54) facing away from the liquid distribution device (34) extends into the suction socket (42) and carries the drive nozzle (56).

9. The surface cleaning head according to claim 8, characterized in that The nozzle cap (78) of the drive nozzle (56) is held in a releasable and fluid-tight manner on the end region (76) of the first branch line (54), wherein the nozzle insert (94) of the drive nozzle (56) rests on one or more supporting surfaces (118) of the first branch line (54).

10. The surface cleaning head according to claim 9, characterized in that The nozzle cap (78) is screwed to the end region (76) of the first branch line (54).

11. The surface cleaning head according to claim 8, characterized in that The first branch line (54) is releasably connected to the liquid distribution device (34).

12. The surface cleaning head according to claim 8, characterized in that The flow rate of cleaning fluid that can be delivered to the drive nozzle (56) via the first branch line (54) is smaller than the flow rate of cleaning fluid that can be delivered to the at least one cleaning nozzle (62, 64) via the second branch line (58).

13. The surface cleaning head of claim 12, wherein: The flow rate of the cleaning fluid that can be delivered to the driving nozzle (56) via the first branch line (54) is at most 50% of the flow rate of the cleaning fluid that can be delivered to the at least one cleaning nozzle (62, 64) via the second branch line (58).

14. A surface cleaning head according to any one of claims 1 to 7, characterised in that A filter device is arranged upstream of the nozzle insert (94) in the flow path of the pressurized cleaning fluid.

15. The surface cleaning head of claim 14, wherein: The filter device has a convexly curved filter surface (120).

16. The surface cleaning head of claim 14, wherein: The filtering device has a bell-shaped filtering surface (120).

17. The surface cleaning head of claim 14, wherein: The filter device has a screen (116).

18. The surface cleaning head of claim 14, wherein: The filter device is arranged directly upstream of the nozzle insert (94).

19. The surface cleaning head of claim 14, wherein: The filter device is arranged in an inner space (80) of the nozzle cap (78).

20. The surface cleaning head of claim 8, wherein: In the flow path of the pressurized cleaning liquid, a filter device is arranged upstream of the nozzle plug-in (94), and the filter device is arranged between the end surface of the nozzle plug-in (94) of the first branch line (54) facing the driving nozzle (56) and the base (96) of the nozzle plug-in (94).

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