Cleaning head and hard surface cleaning device having a cleaning head

Abstract

The invention relates to a cleaning head and a hard surface cleaning apparatus having a cleaning head. The cleaning head (14) has at least one cleaning roller (104, 106) rotatable about an axis of rotation (40), which is held in a rotationally fixed manner on a drive shaft (34) which is rotatable driven. In order to improve the cleaning head (14) in such a way that it has a high mechanical load capacity and a low manufacturing cost, it is proposed according to the invention that the drive shaft (34) has at least one inner shaft portion (44) composed of metal, which is surrounded by an outer shaft portion (46) composed of a plastic material.

Description

TECHNICAL FIELD

[0001] The invention relates to a cleaning head for a hard surface cleaning device, in particular a floor cleaning device, wherein the cleaning head has at least one cleaning roller which is rotatable about an axis of rotation and which is held in a rotationally fixed manner on a rotationally driven drive shaft.

[0002] The invention also relates to a hard surface cleaning device, in particular a floor cleaning device, which has such a cleaning head and has a drive motor for driving the drive shaft of the cleaning head. BACKGROUND

[0003] Hard surface cleaning devices, in particular floor cleaning devices, usually have a cleaning head for cleaning hard surfaces, in particular floors. The cleaning head comprises one or more cleaning rollers which are rotatable about an axis of rotation and which are held in a rotationally fixed manner on a rotationally driven drive shaft. The drive shaft is driven by a drive motor of the hard surface cleaning device, wherein between the drive motor and the drive shaft a transmission is usually arranged for torque transmission and rotational speed reduction. The cleaning rollers can be designed, for example, in the form of brush rollers having a number of cleaning bristles. Alternatively, the cleaning rollers can also have a cleaning coating, for example a cleaning fleece or a cleaning fabric.

[0004] In many cases, the drive shaft is subjected to considerable mechanical loads due to high torques and bending moments. It is therefore common for the drive shaft to be made of metal, in particular steel. However, this requires a number of manufacturing steps and leads to high manufacturing costs for the cleaning head. The outer geometry of the drive shaft also requires considerable effort to match different uses.

[0005] Cleaning heads are also known whose drive shaft is made of plastic. However, this reduces the mechanical load capacity of the drive shaft and thus also of the entire cleaning head. SUMMARY

[0006] It is therefore the task of the present invention to improve a cleaning head of the type mentioned at the outset, which has a high mechanical load capacity and still has low manufacturing costs.

[0007] In the generic cleaning head, this task is solved according to the invention in that the drive shaft has at least one shaft inner part made of metal, which is surrounded by a shaft outer part consisting of a plastic material.

[0008] The cleaning head according to the application is characterized by a high mechanical load capacity and a low manufacturing cost, since the drive shaft can be manufactured inexpensively and still withstand high torques and bending moments. To this end, the drive shaft has at least one shaft inner part composed of metal, which is surrounded by a shaft outer part made of plastic material. The at least one shaft inner part ensures a high mechanical load capacity of the drive shaft, while the shaft outer part made of plastic material allows the outer geometry of the drive shaft to be matched to different uses at low cost.

[0009] Advantageously, the shaft outer part constitutes a plastic shaped part, which is molded onto the at least one shaft inner part. Molding the shaft outer part onto the at least one shaft inner part makes it possible to achieve a significant reduction in manufacturing costs.

[0010] It can be provided that the drive shaft has a plurality of shaft inner parts composed of metal, which are oriented coaxially to the rotational axis of the drive shaft and are surrounded by the shaft outer part.

[0011] The shaft inner parts can be connected to one another in pairs, in particular screwed to one another.

[0012] It can also be provided that the shaft inner parts are arranged loosely next to one another or spaced apart from one another.

[0013] In a particularly preferred design of the application, the drive shaft has a single shaft inner part made of metal, which is embedded in a shaft outer part made of plastic.

[0014] Advantageously, the single shaft inner part is surrounded by the shaft outer part made of plastic on its entire circumference and also at its end sides.

[0015] The at least one shaft inner part is preferably designed cylindrically.

[0016] Alternatively, the at least one shaft inner part can be designed as a polygonal body, in particular as a quadrangular or hexagonal body.

[0017] It can be provided that the at least one shaft inner part is configured as a solid body or also in the form of a tube.

[0018] Advantageously, the shaft inner part has knurling and / or recesses and / or steps, which make it possible to prevent the shaft inner part from moving relative to the shaft outer part in a simple manner.

[0019] In a preferred design of the application, the outer shaft part has at least one recess and / or at least one step on its outer side. Preferably, the at least one recess is designed in the manner of a pocket.

[0020] Advantageously, the volume of the at least one shaft inner part is at least 5% and at most 95% of the total volume of the drive shaft.

[0021] The cross-sectional area of the at least one shaft inner portion over its entire length is preferably at least 5% and at most 95% of the cross-sectional area of the drive shaft.

[0022] In a preferred design of the application, the cleaning head has a transmission for coupling the drive shaft to the drive motor, wherein the shaft outer portion has a fastening section of increased material thickness for fastening a transmission element of the transmission against relative rotation. It is advantageous here for the shaft outer portion to have its greatest diameter in the region of the fastening section.

[0023] The fastening section can for example constitute an end section of the shaft outer portion or for example a middle section of the shaft outer portion.

[0024] It is advantageous for the shaft outer portion to have at least one chamfer in the region of the fastening section, which facilitates the fastening of the transmission element against relative rotation on the fastening section.

[0025] The transmission element is preferably connected in a form-locking manner to the fastening section of the shaft outer portion.

[0026] The transmission preferably has a transmission housing on which the drive shaft is rotatably mounted. The transmission housing accommodates at least the transmission element connected against relative rotation to the shaft outer portion and enables the rotatable mounting of the drive shaft.

[0027] It is advantageous for the drive shaft to pass through at least one through-opening of the transmission housing, wherein the shaft outer portion carries a sleeve in the height of the through-opening, on the outside of which a sealing element for sealing the transmission housing in the circumferential direction is sealingly applied, which surrounds the drive shaft. The transmission housing can be filled with oil. In order to avoid the possible egress of oil via the through-opening, the transmission housing can be sealed in this design of the application by means of a sealing element which is sealingly applied both on the transmission housing and on the outside of the sleeve surrounding the shaft outer portion. The outside of the sleeve constitutes the sealing surface here. This ensures that the sealing element is not damaged by the plastic material of the shaft outer portion. It can for example be provided that the shaft outer portion is composed of a fiber-reinforced plastic material, wherein the use of the sleeve ensures that the fibers of the plastic material do not damage the sealing element.

[0028] The sealing element arranged between the sleeve and the transmission housing can for example be designed in the form of a shaft seal ring, in particular in the form of a radial shaft seal ring.

[0029] The sleeve is preferably pressed onto the shaft outer portion.

[0030] The sleeve can for example be composed of metal.

[0031] Advantageously, a further sealing element, for example a sealing ring, is arranged between the sleeve and the shaft outer part. In this design, the inner side of the sleeve also constitutes a sealing face.

[0032] In an advantageous design of the application, the cleaning head has two cleaning rollers which are rotatable about a rotational axis, wherein the transmission is arranged between the cleaning rollers and wherein the drive shaft passes through the transmission housing and carries the cleaning rollers on its longitudinal section which projects from the transmission housing, respectively. The cleaning rollers which are oriented in line with one another can be driven to rotate about the common rotational axis by means of the drive shaft, wherein the drive shaft can be coupled to the drive motor via the transmission.

[0033] Advantageously, at least one cleaning roller has a roller body and a securing device, wherein the roller body carries a cleaning coating and / or several cleaning bristles on its outer side and can be secured to the drive shaft in a detachable manner by means of the securing device.

[0034] The roller body can be designed in one piece or in multiple pieces. For example, it can be provided that the roller body consists of multiple individual segments.

[0035] Preferably, the securing device is detachably connectable with an axial continuation of the drive shaft.

[0036] Advantageously, the shaft outer part is configured with an axial continuation.

[0037] For example, it can be provided that the roller body can be placed on the longitudinal section of the drive shaft which projects from the transmission housing in the axial direction and can be secured to the drive shaft in a detachable manner by means of the securing device. Here, the securing device cooperates with the axial continuation of the drive shaft.

[0038] For example, it can be provided that the securing device can be screwed to the continuation of the drive shaft.

[0039] As mentioned in the introduction, the application also relates to a hard surface cleaning device, in particular a floor cleaning device. The hard surface cleaning device according to the application has a cleaning head of the type described above and a drive motor for driving the drive shaft of the cleaning head.

[0040] The hard surface cleaning device according to the application is preferably designed as a hand-guided hard surface cleaning device, in particular as a stick device.

[0041] Preferably, the hard surface cleaning device has, in addition to the cleaning head, at least one nozzle via which a cleaning liquid can be applied to the hard surface to be cleaned, in particular to the floor. The pressurized cleaning liquid can be supplied to the hard surface cleaning device, for example, from a water supply network or from a pump.

[0042] Advantageously, the hard surface cleaning device has a rechargeable battery for supplying energy to the drive motor. Attached Figure Description

[0043] The following description of advantageous embodiments of the invention is provided for a more detailed explanation in conjunction with the accompanying drawings. Wherein:

[0044] Figure 1 : A perspective view of a hard surface cleaning device with a cleaning head;

[0045] Figure 2 : Show along Figure 1 A cross-sectional view of the cleaning head along line 2-2;

[0046] Figure 3 : Show along Figure 2 A cross-sectional view of the cleaning head in line 3-3, where the two cleaning rollers of the cleaning head are hidden;

[0047] Figure 4 : Show along Figure 3 A cross-sectional view of the cleaning head along line 4-4;

[0048] Figure 5 : A perspective view showing the drive shaft of the cleaning head;

[0049] Figure 6 : Show Figure 5 A partially cut-out view of the drive shaft. Detailed Implementation

[0050] Figure 1 An advantageous embodiment of the hard surface cleaning device according to the invention is illustrated exemplarily, and is generally denoted by reference numeral 10. The hard surface cleaning device 10 is designed in the form of a hand-guided floor cleaning device 12, which can be manually guided by a user along the floor to be cleaned.

[0051] The floor cleaning device 12 has an advantageous embodiment of the cleaning head 14 according to the invention, which is schematically shown in... Figure 1 and Figure 2 As shown in the image.

[0052] The floor cleaning device 12 includes a main body 16, which has a housing 18 and is connected to an operating unit 22 via a handle 20. The operating unit 22 has a pistol-shaped handle 24 that can be gripped by a user with one hand. A connecting element 26 is arranged on the operating unit 22, which is connected to two nozzles 30, 32 arranged on the main body 16 via a fluid line (not shown in the figure). The fluid line is guided through the handle 20. A water hose (not shown in the figure for better overview) can be connected to the connecting element 26. Water can be supplied to the floor cleaning device 12 from a water supply network or from a pump via the water hose, and the water can be applied to the floor to be cleaned via the nozzles 30, 32.

[0053] The cleaning head 14 is held on the device body 16. The cleaning head has a drive shaft 34 which is coupled via a transmission 36 with an electric drive motor 38 arranged in the housing 18 of the device body 16, by means of which the drive shaft 34 can be set in rotation about an axis of rotation 40. In order to supply the drive motor 38 with electrical energy, a rechargeable battery 42 is held in a detachable manner on the operating unit 22, which is electrically coupled with the drive motor 38 via electrical lines not shown in the drawing. The electrical lines are guided through the handle 20. In order to switch the drive motor 38 on and off, an electrical switch is arranged on the handle 24 of the operating unit 22, which has a switching lever 39 which can be manipulated by the user.

[0054] As an alternative or in addition to the rechargeable battery 42, a power cable can be provided via which the floor cleaning device 12 can be coupled with a power supply network.

[0055] The drive shaft 34 has an inner shaft portion 44 which consists of metal, preferably of steel. Furthermore, the drive shaft 34 has an outer shaft portion 46 which consists of a plastic material, in particular a fiber-reinforced plastic material, and which surrounds the inner shaft portion 44. The outer shaft portion 46 constitutes a plastic shaped part, in particular an injection molded part, which is molded onto the inner shaft portion 44.

[0056] As is particularly clear from Figure 6 the inner shaft portion 44 has a constant diameter over its entire length. However, it can also be provided that the inner shaft portion 44 has elevations, depressions and / or steps. Alternatively, the inner shaft portion 44 can also be designed as a polygonal body.

[0057] The outer shaft portion 46 constitutes a housing 48 which surrounds the inner shaft portion 44 in the circumferential direction and has a plurality of depressions 49, elevations 50 and steps 51 on its outer side.

[0058] The outer shaft portion 46 constitutes an axially oriented first continuation 52 and a second continuation 54 with its end sections. The continuations 52 and 54 are integrally connected with the housing 48 and cover the end sides 56, 58 of the inner shaft portion 44. The first continuation 52 constitutes a first outer thread 60 and the second continuation 54 constitutes a second outer thread 62.

[0059] The outer shaft portion 46 has a material-thickness-increased fastening section 64 centrally in the longitudinal direction. The fastening section is configured with two mutually opposite truncations 66, 68. In the region of the fastening section 64, the outer shaft portion 46 has its greatest diameter, which decreases stepwise in the direction of the continuations 52, 54.

[0060] The transmission 36 has a transmission housing 70, which is penetrated by the drive shaft 34. For this purpose, the transmission housing 70 has a first through-opening 72 and a second through-opening 74. At the height of the through-openings 72, 74, the drive shaft 34 carries a sleeve 76, 78, respectively, which is pressed onto the shaft outer portion 46 and is thus connected in a rotationally fixed manner thereto. Preferably, the sleeves 76, 78 are composed of metal. Between the sleeves 76, 78 and the shaft outer portion 46, a sealing ring 80 or 82, respectively, is arranged in order to seal the respective sleeve 76, 78 against the shaft outer portion 46. Between the sleeves 76, 78 and the transmission housing 70, a sealing element in the form of a radial shaft sealing ring 84 or 86, respectively, is arranged in order to seal the drive shaft 34 against the transmission housing 70. The sleeves 76, 78 utilize their outer sides to form a sealing surface, against which the radial shaft sealing rings 84, 86 are sealingly pressed even when the drive shaft 34 is rotating. The sleeves 76, 78 ensure that the radial shaft sealing rings 84, 86 are not damaged by the fiber-reinforced plastic material of the shaft outer portion 46 even when the drive shaft 34 is rotating.

[0061] The drive shaft 34 is rotatably supported on the transmission housing 70 by means of a first bearing 88 and a second bearing 90.

[0062] The transmission 36 is configured as a worm gear 92, via which the drive shaft 34 is coupled with a motor shaft 94 of the drive motor 38. The worm gear 92 has a worm wheel 96, which is held in a rotationally fixed manner on the fastening section 64 between the first bearing 88 and the second bearing 90, wherein the worm wheel 96 is pressed onto the cut-off portions 66, 68.

[0063] The worm wheel 96 is in operative connection with a worm shaft 98, which is connected in a rotationally fixed manner with the motor shaft 94. This is apparent from Figure 4

[0064] The drive shaft 34 has a first longitudinal section 100 and a second longitudinal section 102, which are opposite one another and each extend from the transmission housing 70. A first cleaning roller 104 is held in a rotationally fixed manner on the first longitudinal section 100 and a second cleaning roller 106 is held in a rotationally fixed manner on the second longitudinal section 102.

[0065] The first cleaning roller 104 has a first roller body 108, which carries a first brush portion 110 on its outer side, which has a number of cleaning bristles 112. In a corresponding manner, the second cleaning roller 106 has a second roller body 114, which carries a second brush portion 116 on its outer side, which has a number of cleaning bristles 118.

[0066] ​The roller bodies 108, 114 can be designed in one piece or in multiple pieces. In particular, the roller bodies 108, 114 can consist of multiple single segments.

[0067] In order to axially secure the first cleaning roller 104 on the drive shaft 34, the first cleaning roller 104 has a first securing device 120. The first securing device 120 comprises a first securing body 122 which can be inserted into a recess 124 of the first roller body 108 in the axial direction and is screwed with a first continuation 52 of the shaft-external portion 46 which projects into the recess 124. The first securing body 122 carries, at its end facing away from the first continuation 52, a first securing flange 126 which projects from the recess 124 and which bears against an end side 128 of the first roller body 108 facing away from the transmission housing 70.

[0068] In order to axially secure the second cleaning roller 106 on the drive shaft 34, the second cleaning roller 106 has a second securing device 130. The second securing device 130 comprises a second securing body 132 which can be inserted into a recess 134 of the second roller body 114 in the axial direction and is screwed with a second continuation 54 of the shaft-external portion 46 which projects into the recess 134. The second securing body 132 carries, at its end facing away from the second continuation 54, a second securing flange 136 which bears against an end side 138 of the second roller body 114 facing away from the transmission housing 70.

[0069] The two cleaning rollers 104, 106 are held on the drive shaft 34 in a detachable manner. In order to detach the first cleaning roller 104 from the drive shaft 34, the first securing body 122 can be unscrewed from the first continuation 52, so that the first roller body 108 can subsequently be pulled off the first longitudinal section 100 of the drive shaft 34. In a corresponding manner, the second securing body 132 can be unscrewed from the second continuation 54, so that the second roller body 114 can subsequently be pulled off the second longitudinal section 102 of the drive shaft 34.

Claims

1. A cleaning head for a hard surface cleaning apparatus, wherein, The cleaning head (14) has at least one cleaning roller (104, 106) rotatable about an axis of rotation (40), which is held in a rotationally fixed manner on a rotationally driven drive shaft (34), characterized in that the drive shaft (34) has at least one shaft inner portion (44) composed of metal, which is surrounded by a shaft outer portion (46) composed of a plastic material.

2. The cleaning head of claim 1, wherein, The shaft outer portion (46) constitutes a plastic shaped part, which is molded onto the at least one shaft inner portion (44).

3. The cleaning head of claim 1, wherein, The drive shaft (34) has a unique shaft inner portion (44) embedded in the shaft outer portion (46).

4. The cleaning head of claim 1, wherein, The at least one shaft inner portion (44) is designed cylindrically or as a polygonal body.

5. The cleaning head of any one of claims 1 to 4, wherein, The shaft outer portion (46) has recesses (49) and / or elevations (50) and / or steps (51) on its outer side.

6. The cleaning head of any one of claims 1 to 4, wherein, The cleaning head (14) has a transmission (36) for coupling the drive shaft (34) to a drive motor (38), wherein the shaft outer portion (46) has a material-thickened fastening section (64) for fastening a transmission element (96) of the transmission (36) in a rotationally fixed manner.

7. The cleaning head of claim 6, wherein, The transmission (36) has a transmission housing (70), on which the drive shaft (34) is rotatably supported.

8. The cleaning head of claim 7, wherein, The drive shaft (34) passes through at least one through-opening (72, 74) of the transmission housing (70), wherein the shaft outer portion (46) has a sleeve (76, 78) in the height of the through-opening (72, 74), against the outer side of which a sealing element (84, 86) surrounding the drive shaft (34) in the circumferential direction sealingly rests for sealing the transmission housing (70).

9. The cleaning head of claim 8, wherein, Between the sleeve (76, 78) and the shaft outer portion (46) a sealing ring (80, 82) is arranged.

10. The cleaning head of claim 6, wherein, The cleaning head (14) has two cleaning rollers (104, 106) rotatable about the axis of rotation (40), wherein the transmission (36) is arranged between the cleaning rollers (104, 106), and wherein the drive shaft (34) passes through the transmission housing (70) and carries a cleaning roller (104, 106) on a longitudinal section (100, 102) of the drive shaft projecting from the transmission housing (70), respectively.

11. The cleaning head of any one of claims 1 to 4, wherein, The at least one cleaning roller (104, 106) has a roller body (108, 114) and a securing device (120, 130), wherein the roller body (108, 114) carries a cleaning coating and / or a plurality of cleaning bristles (112, 118) on its outer side and can be detachably secured to the drive shaft (34) by means of the securing device (120, 130).

12. The cleaning head of claim 11, wherein, The securing device (120, 130) can be detachably connected with an axial continuation (52, 54) of the drive shaft (34).

13. The cleaning head of claim 12, wherein, The shaft outer portion (46) is configured with the axial continuation (52, 54). The at least one cleaning roller (104, 106) has a roller body (108, 114) and a securing device (120, 130), wherein the roller body (108, 114) carries a cleaning coating and / or a plurality of cleaning bristles (112, 118) on its outer side and can be detachably secured to the drive shaft (34) by means of the securing device (120, 130). The securing device (120, 130) can be detachably connected with an axial continuation (52, 54) of the drive shaft (34). The shaft outer portion (46) is configured with the axial continuation (52, 54).

14. Hard surface cleaning device having a cleaning head (14) according to any one of claims 1 to 4 and a drive motor (38) for driving a drive shaft (34) of the cleaning head (14).

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