Water-tight and robust motor suspension

Abstract

The invention relates to a watertight and robust motor suspension. The invention relates to a motor suspension for rigid and watertight mounting of a motor to a housing of an electric device, an electric device comprising such a motor suspension and a hair cutting device comprising an electric device with such a motor suspension. The motor suspension comprises a motor fixation element, a sealing suspension element and a motor shaft seal. The motor fixation element is configured to provide a rigid connection of the motor to the housing in one direction while it provides a certain flexibility in the other direction to let the housing not deform. The sealing suspension element is configured for providing a fluid-tight connection to the housing and the motor shaft seal is configured for providing a fluid-tight connection of the sealing suspension element to a rotational shaft of the motor.

Description

TECHNICAL FIELD

[0001] The invention relates to a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device, to an electrically operated device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device, and to a hair cutting device comprising an electrically operated device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device. BACKGROUND

[0002] In electrically operated devices operating with a reciprocating movement of an element, such as a cutting element of a trimmer, the rotational movement of the motor output shaft is transformed into a reciprocating movement. Friction and forces against the reciprocating movement result in forces acting on the motor output shaft in the direction of the reciprocating movement. To achieve watertightness of the electrically operated device and to shield the internal components, a flexible seal can be placed between the rotational shaft of the motor and the housing of the electrically operated device. One or more rubber seals are typically used to shield the interior of the device from water. The rubber seal is part of the drivetrain robustness. It is located between the housing to which the stationary part of the cutting element is connected and the motor and / or motor shaft to which the moving part of the cutting element is connected. The flexibility of the seal is required to create the desired watertightness. Especially in cases where the rotational movement is transformed into a linear movement, such a seal can negatively influence the strength and clarity of the linear movement under different load conditions. Due to this flexibility of the seal, the construction of the drivetrain becomes less rigid, which results in a vibrating movement of the motor output shaft in the direction of the reciprocating movement. This can result in a loss of stroke of the reciprocating movement, especially under high load conditions. Typical examples of such devices are hair cutting devices like beard trimmers and hair clippers, but also toothbrushes, kitchen tools like blenders and electric saws, and garden tools or other tools like hedge trimmers and saws can suffer from this drawback.

[0003] CN 202 858 906 U discloses a multi-stage compact sealing structure of a blender having a first sealing ring and a second sealing ring.

[0004] CN 102 638 122 B discloses a driven shear motor having a bracket, a rotor unit and two bearings.

[0005] In electric appliances having a moving function driven by a rotational shaft and requiring watertightness, a solution is required. For these reasons, it would be advantageous to have a motor suspension that does not suffer from the drawbacks mentioned above. SUMMARY

[0006] It is an object of the invention to provide a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device with improved performance.

[0007] The objects of the application are solved by the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims.

[0008] The described embodiments equally relate to a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device, to an electrically operated device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device, and to a hair cutting device comprising an electrically operated device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device. Although not described in detail, synergistic effects can result from different combinations of embodiments.

[0009] Further still, it should be noted that all embodiments of the application with respect to the method can be performed in the order of the described steps, however, this does not necessarily have to be the only and necessary order of the steps of the method. Unless explicitly mentioned to the contrary hereinafter, the method as presented herein can be performed in another order of the disclosed steps without departing from the respective method embodiment.

[0010] According to a first aspect of the present application, a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically operated device is provided. The motor suspension comprises a motor fixation element, a sealing suspension element and a motor shaft seal. A stator of a motor to be mounted is fixably connected to the motor fixation element. The sealing suspension element is configured for providing a fluid-tight connection of the sealing suspension element to the housing of the electrically operated device. The motor shaft seal has a first sealing surface fluid-tightly connected to the sealing suspension element, and the motor shaft seal has a second sealing surface adapted for fluid-tightly receiving a rotational axis of the motor to be mounted. The rotational axis is configured for driving a reciprocating movement of a tool to be connected. The motor fixation element is configured for forming a connection to an inner peripheral surface of the housing of the electrically operated device along at least a portion of an outer peripheral surface of the motor fixation element, which connection is rigid in a first direction, which first direction is substantially perpendicular to a direction of a longitudinal extension of the rotational axis and substantially parallel to a direction of the reciprocating movement. The rigid connection comprises a first connection section and a second connection section, wherein the first connection section and the second connection section are opposite to each other with respect to the rotational axis of the motor to be mounted.

[0011] The motor suspension comprises a motor fixation element, a sealing suspension element and a motor shaft seal. The motor fixation element is connected to the motor and it provides a rigid connection of the motor fixation element to the housing of the electric device in a direction perpendicular to the rotation axis. The motor fixation element and the motor can be inserted into the housing of the electric device such that a part of the outer circumferential surface of the motor fixation element forms a rigid connection with a part of the inner circumferential surface of the housing of the electric device. The sealing suspension element provides a fluid-tight connection to the housing of the electric device. Further, the sealing suspension element is fluid-tight connected to a first sealing surface of the motor shaft seal and a second sealing surface of the motor shaft seal is fluid-tight connected to the rotation axis of the motor.

[0012] The motor fixation element can be connected to the motor to prevent a relative rotation of the motor and the motor fixation element around an axis parallel to the rotation axis, for example by one or more screws or protrusions mounted in screw holes of the motor. Further, the motor fixation element provides a rigid connection of the motor to the housing at least in a first direction. This first direction can be the direction of the reciprocating movement of the cutting tool drivingly connected to the rotation axis and can be substantially perpendicular to the rotation axis and substantially parallel to the direction of the reciprocating movement. Substantially perpendicular or substantially parallel should be understood to include a deviation of up to fifteen degrees in any direction.

[0013] The sealing suspension element together with the motor shaft seal provides a fluid-tight enclosure of the motor in the housing and ensures a fluid tightness between the motor shaft and the housing from which the rotation axis of the motor extends. The sealing suspension element and the housing can be two separate parts fluid-tight connected with the housing seal. However, the sealing suspension element and the housing can also be integrated as one single part.

[0014] The stiff connection between the motor fixation element and the housing can be achieved via at least two connection sections of opposite sides of the motor fixation element. The connection sections can be located at the outer circumferential surface of the motor fixation element in a way that the rotation axis of the motor is perpendicular to a straight line between the first connection section and the second connection section. The first direction in which the rigid connection is provided is perpendicular to the straight line between the first connection section and the second connection section and perpendicular to the rotation axis.

[0015] In an embodiment of the invention, the motor fixation element has the form of a plate perpendicular to the rotation axis of the motor to be mounted and comprises at least one through slot transversely to a straight line between one of the first connection section and the second connection section and the rotation axis of the motor to be mounted to achieve a resilient connection between the motor to be mounted to the motor fixation element and the housing of the electric device in a direction substantially perpendicular to the longitudinal extension of the rotation axis and in a direction substantially perpendicular to the direction of the reciprocating movement.

[0016] The motor fixation element can have the shape of a plate extending perpendicular to the rotation axis. Two through-slots parallel to the first direction and between the connection sections on either side of the rotation axis of the motor provide a certain flexibility of the motor fixation element in the direction of the straight line from the first connection section to the second connection section, respectively. Thus, the motor can be flexibly mounted to the housing in a direction perpendicular to the reciprocating movement of the cutting tool and perpendicular to the rotation axis, while the connection can be rigid in the first direction of the reciprocating movement of the cutting tool. This flexibility ensures a good fit between the motor fixation element and the housing at least at the two connection sections, so that the connection is rigid in the first direction, while the motor fixation element does not exert too much pressure on the housing, so that the housing deforms. Excessive pressure on the housing can deform the housing and make the fluid tightness of the connection of the sealing suspension element to the housing worse. By avoiding such deformations, the fluid tightness can be improved.

[0017] In embodiments of the application, the motor fixation element comprises at least one recess or protrusion configured to tightly accommodate an opposite protrusion or recess, respectively, of a housing of the electrically powered device, wherein the at least one recess tightly accommodating the respective protrusion forms at least a portion of a rigid connection to an inner peripheral surface of the housing of the electrically powered device along at least a portion of an outer peripheral surface of the motor fixation element.

[0018] The rigid connection of the motor fixation element to the housing can be achieved at least at the connection sections. The outer peripheral surface of the motor fixation element can be connected to the inner peripheral surface of the housing. The connection can be achieved by a recess accommodating a protrusion. The protrusion can extend into the recess, thereby forming a rigid connection in one direction, while leaving a certain flexibility in another direction. The recess can be located in the motor fixation element and the protrusion can be located at the housing, or the recess can be located at the housing and the protrusion can be located at the motor fixation element.

[0019] In embodiments of the application, the motor fixation element comprises at least two recesses symmetrically distributed along the outer peripheral surface to accommodate respective protrusions of a housing of the electrically powered device.

[0020] The two recesses can be located at opposite sides of the outer peripheral surface of the motor fixation element. Protrusions of the outer peripheral surface of the housing can be accommodated in these recesses.

[0021] In embodiments of the application, at least one of the protrusion and the recess has an inclined surface to self-center the respective accommodating recess and protrusion.

[0022] The recess of the motor fixation element and the protrusion of the housing can have a trapezoidal or triangular shape. In this embodiment of the invention, the inclined surfaces of the trapezoidal or triangular shape can lead to a self-centering of the protrusion in the recess and in combination with the flexibility of the motor fixation element in the straight direction between the first fixation section and the second fixation section. This ensures a good fit without gaps at the at least two connection sections, does not exert too much pressure on the housing to deform the housing and the pressure is never released from the fluid-tight seal.

[0023] In an embodiment of the invention, the sealing suspension element has a sealing surface for a housing seal, wherein the motor suspension further comprises a housing seal, wherein the housing seal is adapted to provide a fluid-tight connection of the sealing suspension element with the housing of the electric device.

[0024] The fluid-tight sealing of the sealing suspension element is achieved by a housing seal between the sealing surface of the sealing suspension element and the inner circumferential surface of the housing.

[0025] In an embodiment of the invention, the sealing surface of the sealing suspension element is an outer circumferential sealing surface, wherein the housing seal is an O-ring compressible between the outer circumferential sealing surface of the sealing suspension element and a corresponding inner circumferential surface of the housing.

[0026] The sealing surface of the sealing suspension element can be on an outer circumferential surface of the sealing suspension element. Thus, in this embodiment of the invention, the sealing surface is opposite to the inner circumferential surface of the housing and the O-ring as housing seal can be compressed between the sealing suspension element and the housing.

[0027] In an embodiment of the invention, the outer circumferential sealing surface of the sealing suspension element has an elliptical shape with a continuously convex outer circumference for uniformly compressing the O-ring to a corresponding concave inner circumferential surface of the housing of the electric device.

[0028] The outer circumferential sealing surface of the sealing suspension element can have a continuously convex shape such that the curvature always has the same direction without any edges or straight sections. The inner circumferential surface of the housing can have a corresponding continuously concave shape such that in this embodiment of the invention the O-ring can be uniformly compressed between the convex surface of the sealing suspension element and the concave surface of the housing.

[0029] In an embodiment of the invention, the motor shaft seal comprises an abutment surface opposite to the first sealing surface for receiving the motor fixation element, wherein the motor shaft seal is compressed and thereby fixed between the sealing suspension element and the motor fixation element.

[0030] The motor shaft seal can be fixed and connected to the sealing suspension element by compression between the sealing suspension element and the motor fixation element.

[0031] In an embodiment of the invention, the motor suspension is configured for providing a rigid connection of the motor to be mounted and the housing of the electric device in the first direction, to enable conversion of the rotational movement of the rotational shaft into a linear reciprocating movement and to reduce vibrations of the motor in the first direction in the housing.

[0032] The linear reciprocating movement results in a force acting on the rotational shaft of the motor in the first direction parallel to the reciprocating movement. To avoid vibrations of the rotational shaft, the connection of the rotational shaft to the housing has to be solid with respect to the first direction. Thus, the rotational movement can be transformed into a reciprocating movement without stroke loss and without excessive loss of energy due to vibrations. The configuration of this embodiment of the invention is such that there is a rigid connection between the rotational shaft of the motor and the housing in the direction of movement in the first direction, in which the highest forces can be applied. In addition, in this embodiment of the invention, the connection of the motor fixation element to the housing does not exert any forces to the housing, which could cause deformation of the housing.

[0033] In an embodiment of the invention, the motor suspension is configured for providing a fluid-tight enclosure of the motor in the housing and for the rotational shaft to extend out of the motor suspension longitudinally and to be fixed in terms of translation to prevent translation in the first direction.

[0034] The motor suspension can provide a fluid-tight enclosure of the motor in the housing, thereby protecting the electric components from fluids. The rotational shaft of the motor can extend through an orifice of the motor shaft seal, while the motor shaft seal can provide a fluid-tight connection to the rotational shaft.

[0035] According to another aspect of the invention, an electric device comprising a motor suspension according to any of the preceding embodiments is provided. The electric device comprises a motor having a stator and a rotational shaft, wherein the stator of the motor is mounted to the motor fixation element and the rotational shaft is received fluid-tightly by the second sealing surface of the motor shaft seal.

[0036] The electric device can comprise a motor suspension as described in the previous embodiments of the invention. The electric device further comprises a motor having a stator and a rotational shaft. The motor can be mounted to the motor fixation element and thereby connected to the housing of the electric device, thereby enabling a rigid connection in the first direction.

[0037] In an embodiment of the invention, the motor fixation element and the one or more through-slots formed in the motor fixation element have a higher deformability than the housing of the electric device in the direction from the rotational shaft to the respective connection section, such that a transverse force applied to the rotational shaft of the motor to be mounted deforms the motor fixation element, rather than the inner peripheral surface of the housing.

[0038] The slot formed in the motor fixation element provides a resilient connection of the motor fixation element to the housing in a direction perpendicular to the first direction, which is defined by the reciprocating movement. However, the slot does not deteriorate the rigidity in a direction parallel to the first direction. Thus, a rigid connection of the motor fixation element to the housing in the first direction can be provided without deforming the housing of the electric device. Thus, in this embodiment of the present invention, the sealing suspension element can provide a fluid-tight connection to the housing and the motor shaft seal can provide a fluid-tight connection to the rotational shaft of the motor.

[0039] According to another aspect of the present invention, a hair cutting device comprising an electric device according to any of the preceding embodiments is provided. The hair cutting device further comprises a cutting tool drivingly connected to the rotational shaft of the motor, wherein a main cutting direction of the cutting tool is transversal to a straight line connecting the opposite first and second connection sections.

[0040] Typical examples of water-tight products having a reciprocating movement generated by a rotational shaft of a motor are e.g. hair cutting devices like a beard trimmer, a hair cutter or a shaver, but also toothbrushes, kitchen tools like a blender and an electric knife or saw, and gardening or medical tools like a hedge trimmer and a saw. They usually comprise a first part of a cutting tool performing the reciprocating movement, which is achieved by a connection to the rotational shaft of the motor. A second part of the cutting tool can be connected to the housing, such that the first part of the cutting tool moves in the first direction relative to the second part of the cutting tool. The motor can be mounted into the housing from the top side. Depending on the form and function of the appliance, the motor can also be mounted into the housing from the bottom side.

[0041] Furthermore, the motor suspension can be realized with a reduced number of components, such that the motor fixation element and the sealing suspension element are integrated into one part.

[0042] The benefits provided by any of the above aspects apply equally to all other aspects and vice versa.

[0043] In general, the present invention relates to a motor suspension for rigid and water-tight mounting of a motor to a housing of an electric device, an electric device comprising such a motor suspension and a hair cutting device comprising an electric device having such a motor suspension. The motor suspension comprises a motor fixation element, a sealing suspension element and a motor shaft seal. The motor fixation element is configured to provide a rigid connection of the motor to the housing in one direction, while it provides a certain flexibility in another direction to not deform the housing. The sealing suspension element is configured for providing a fluid-tight connection to the housing and the motor shaft seal is configured for providing a fluid-tight connection of the sealing suspension element to the rotational shaft of the motor.

[0044] The above aspects and embodiments will become clear and will be illustrated in the description hereinafter with reference to the examples described hereinafter. In the following, exemplary embodiments of the present application will be described with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 A schematic setup of a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a first exemplary embodiment of the present application is shown.

[0046] Figure 2 A schematic setup of a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a second exemplary embodiment of the present application is shown.

[0047] Figure 3 A schematic setup of an electrically driven device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a third exemplary embodiment of the present application is shown.

[0048] Figure 4 A first cross-sectional view of an electrically driven device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a third exemplary embodiment of the present application is shown.

[0049] Fig. 5a shows a second cross-sectional view of an electrically driven device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a third exemplary embodiment of the present application.

[0050] Fig. 5b shows a cross-sectional view of an electrically driven device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a fourth exemplary embodiment of the present application.

[0051] Figure 6 A schematic setup of a hair cutting device comprising an electrically driven device comprising a motor suspension for rigid and watertight mounting of a motor to a housing of an electrically driven device according to a fifth exemplary embodiment of the present application is shown. DETAILED DESCRIPTION

[0052] Figure 1A schematic setup of a motor suspension 100 for rigid and watertight mounting of a motor 160 to a housing 170 of an electric device 200 according to a first exemplary embodiment of the present application is shown. The motor suspension 100 comprises a motor fixation element 110 connectable to the motor 160, a sealing suspension element 120, and a motor shaft seal 130 having a first sealing surface 131 and a second sealing surface 132. The first sealing surface 131 is connected to the sealing suspension element 120, and the second sealing surface 132 is connectable to a rotating shaft 161 of the motor 160. The motor 160 is connectable to the motor fixation element 110, which is configured for providing a rigid connection to the housing 170 in a first direction 140. The sealing suspension element 120 is configured for providing a fluid-tight connection to the housing 170.

[0053] Figure 2 A schematic setup of a motor suspension 400 for rigid and watertight mounting of a motor 160 to a housing 170 of an electric device 200 according to a second exemplary embodiment of the present application is shown. In this embodiment of the present application, the sealing suspension element 120 is an integrated part of the housing 170.

[0054] Figure 3 A schematic setup of an electric device 200 comprising a motor suspension 100 for rigid and watertight mounting of a motor 160 to a housing 170 of the electric device 200 according to a third exemplary embodiment of the present application is shown. A stator 162 of the motor 160 is connected to the motor fixation element 110. The motor fixation element 110 provides a rigid connection to the housing 170 of the electric device 200 in a direction perpendicular to a rotating shaft 161 of the motor 160. Along at least a portion of an outer peripheral surface 111 of the motor fixation element 110, a rigid connection to an inner peripheral surface 171 of the housing 170 of the electric device is formed. The sealing suspension element 120 is fluid-tightly connected to the housing with a housing seal 123 compressed between a sealing surface 121 of the sealing suspension element 120 and the inner peripheral surface 171 of the housing 170. The motor shaft seal 130 is fluid-tightly connected to the sealing suspension element 120 with the first sealing surface 131 and to the rotating shaft 161 of the motor 160 with the second sealing surface 132.

[0055] Figure 4 A first cross-sectional view of an electric device 200 comprising a motor suspension 100 for rigid and watertight mounting of a motor 160 to a housing 170 of the electric device 200 according to a third exemplary embodiment of the present application is shown. In the first cross-sectional view, the motor fixation element 110 is indicated with A-A. Figure 3 The horizontal of the first cross-sectional view is indicated with A-A in Figure 4A housing seal 123 is shown compressed between a sealing surface 121 of the sealing suspension element 120 and an inner circumferential surface 171 of the housing 170. Although not clearly depicted in the figures, the sealing surface 121 and the inner circumferential surface 171 do not comprise straight sections, but have a convex and a concave shape, respectively. A motor shaft seal 130 is fixed between the sealing suspension element 120 and the motor fixation element 110. A rotation shaft 161 of the motor 160 extends through an orifice of the motor shaft seal 130.

[0056] Fig. 5a shows a second cross-sectional view of the electrically powered device 200 comprising the motor suspension 100 for rigid and watertight mounting of the motor 160 to the housing 170 of the electrically powered device 200 according to a third exemplary embodiment of the present application. In Figure 3 The horizontal of the second cross-sectional view is indicated with B-B in Fig. 5a. Fig. 5a shows a rigid connection 150 of the motor fixation element 110 to the housing 170 of the electrically powered device 200. A first connection section 151 and a second connection section 152 are located at opposite sides of the outer circumferential surface 111 of the motor fixation element 110. At each connection section 151, 152, the motor fixation element 110 comprises a trapezoidal notch 153 with an inclined surface 155. These notches 153 accommodate corresponding protrusions 154 formed on the inner circumferential surface 171 of the housing 170, thereby forming a rigid connection in the first direction 140. Two through-slots 112 are formed in the motor fixation element 110, which extend parallel to the first direction 140 and are located between the rotation shaft 161 of the motor 160 and the first connection section 151 and the second connection section 152, respectively. Thus, the notches 153 are flexible and movable along a straight line from the first connection section 151 to the second connection section 152 and provide a rigid connection of the motor fixation element 110 to the housing 170 without any deformation of the housing 170.

[0057] Fig. 5b shows a cross-sectional view of the electrically powered device 200 comprising the motor suspension 100 for rigid and watertight mounting of the motor 160 to the housing 170 of the electrically powered device 200 according to a fourth exemplary embodiment of the present application. In contrast to Fig. 5a, Fig. 5b shows protrusions 157 located at the motor fixation element 110 and notches 156 located at the housing 170.

[0058] Figure 6A schematic setup of a hair cutting device 300 comprising an electrically powered device 200 according to a fifth exemplary embodiment of the present application is shown, the electrically powered device 200 comprising a motor suspension 100 for rigid and watertight mounting of a motor 160 to a housing 170 of the electrically powered device 200. The hair cutting device 300 further comprises a cutting tool 310 drivenly connected to a rotating shaft 161 of the motor 160 and a comb 320 connected to the housing 170. The housing 170 can be integrated in a housing of the hair cutting device 300 and can extend beyond the sealing suspension element 120 and the rotating shaft 161. A main cutting direction of the cutting tool 310 is parallel to the first direction 140.

[0059] While the application has been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered illustrative or exemplary only and not restrictive. The application is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practising the claimed application, from a study of the drawings, the disclosure, and the appended claims.

[0060] In the claims, the word "comprising" does not exclude other elements or steps, and the

[0061] List of reference signs:

[0062] 100, 400 motor suspension

[0063] 110 motor fixation element

[0064] 111 outer peripheral surface

[0065] 112 through slot

[0066] 120 sealing suspension element

[0067] 121 sealing surface

[0068] 123 housing seal

[0069] 130 motor shaft seal

[0070] 131 first sealing surface

[0071] 132 second sealing surface

[0072] 140 first direction

[0073] 150 rigid connection

[0074] 151 first connection section

[0075] 152 second connection section

[0076] 153 recess of motor fixation element

[0077] 154 protrusion of housing

[0078] 155 inclined surface

[0079] 156 recess of housing

[0080] 157 protrusion of motor fixation element

[0081] 160 motor

[0082] 161 rotation axis

[0083] 162 stator

[0084] 170 housing

[0085] 171 inner circumferential surface

[0086] 200 electric device

[0087] 300 hair cutting device

[0088] 310 cutting tool

[0089] 320 comb

Claims

1. Motor suspension for rigid and watertight mounting of a motor (160) to a housing (170) of an electrically powered device (200), the motor suspension comprising: a motor fixation element (110) to which a stator (162) of a motor (160) to be mounted can be fixedly connected, a sealing suspension element (120), and a motor shaft seal (130); wherein the sealing suspension element (120) is configured for providing a fluid-tight connection of the sealing suspension element (120) to a housing (170) of an electrically powered device (200); wherein the motor shaft seal (130) has a first sealing surface (131) fluid-tightly connected to the sealing suspension element (120), wherein the motor shaft seal (130) has a second sealing surface (132) adapted for fluid-tightly receiving a rotating shaft (161) of the motor (160) to be mounted, wherein the rotating shaft (161) is configured for driving a reciprocating movement of a tool to be connected, wherein the motor fixation element (110) is configured for forming a rigid connection (150) to an inner peripheral surface (171) of the housing (170) of the electrically powered device (200) along at least a portion of an outer peripheral surface (111) of the motor fixation element (110), the rigid connection (150) being rigid in a first direction (140) which is substantially perpendicular to a direction of a longitudinal extension of the rotating shaft (161) and substantially parallel to a direction of the reciprocating movement, characterized in that the rigid connection (150) comprises a first connection section (151) and a second connection section (152), wherein the first connection section (151) and the second connection section (152) are opposite to each other with respect to the rotating shaft (161) of the motor (160) to be mounted; wherein the motor fixation element (110) has the form of a plate perpendicular to the rotating shaft (161) of the motor (160) to be mounted and comprises at least one through slot (112) transverse to a straight line between one of the first connection section (151) and the second connection section (152) and the rotating shaft (161) of the motor (160) to be mounted for enabling a resilient connection between the motor (160) to be mounted to the motor fixation element (110) and the housing (170) of the electrically powered device (200) in a direction substantially perpendicular to the direction of the longitudinal extension of the rotating shaft (161) and substantially perpendicular to the direction of the reciprocating movement.

2. The motor suspension according to claim 1, wherein the motor fixation element (110) comprises at least one recess or protrusion, respectively, configured for tightly accommodating the opposite protrusion or recess of the housing (170) of the electric device (200), respectively, wherein the at least one recess tightly accommodating a respective protrusion forms at least a portion of the rigid connection (150) with an inner peripheral surface (171) of the housing (170) of the electric device (200) along at least a portion of the outer peripheral surface (111) of the motor fixation element (110).

3. The motor suspension according to any one of claims 1-2, wherein the motor fixation element (110) comprises at least two recesses symmetrically distributed along the outer peripheral surface (111) to accommodate respective protrusions of the housing (170) of the electric device (200).

4. The motor suspension according to claim 2, wherein at least one of the protrusion and the recess has an inclined surface (155) to self-center the respective accommodating recess and protrusion.

5. The motor suspension according to any one of claims 1-2, wherein the sealing suspension element (120) has a sealing surface (121) for a housing seal (123), wherein the motor suspension further comprises a housing seal (123), wherein the housing seal (123) is adapted to provide the fluid-tight connection of the sealing suspension element (120) with the housing (170) of the electric device (200).

6. The motor suspension according to claim 5, wherein the sealing surface (121) of the sealing suspension element (120) is an outer peripheral sealing surface, wherein the housing seal (123) is an O-ring compressible between the outer peripheral sealing surface of the sealing suspension element (120) and a corresponding inner peripheral surface (171) of the housing (170).

7. The motor suspension according to claim 6, wherein the outer peripheral sealing surface of the sealing suspension element (120) has an elliptical shape with a continuously convex outer periphery for uniformly compressing the O-ring to a correspondingly concave inner peripheral surface (171) of the housing (170) of the electric device (200).

8. The motor suspension according to any one of claims 1-2, wherein the motor shaft seal (130) comprises an abutment surface opposite the first sealing surface (131) for receiving the motor fixation element (110), wherein the motor shaft seal (130) is compressed and thereby fixed between the sealing suspension element (120) and the motor fixation element (110).

9. The motor suspension according to any of claims 1-2, wherein the motor suspension is configured for providing, in the first direction (140), a rigid connection (150) of the motor (160) to be mounted and the housing (170) of the electric device (200) to enable a conversion of a rotational movement of the rotational shaft (161) into a linear reciprocating movement and to reduce vibrations of the motor (160) in the first direction (140) in the housing (170).

10. The motor suspension according to any of claims 1-2, wherein the motor suspension is configured for providing a fluid-tight enclosure of the motor (160) in the housing (170) and a longitudinal extension of the rotational shaft (161) out of the motor suspension and a fixation in terms of translation to prevent a translation in the first direction (140).

11. An electric device (200) comprising a motor suspension according to any of the preceding claims, wherein the electric device (200) comprises a motor (160) having a stator (162) and a rotational shaft (161), wherein the stator (162) of the motor (160) is mounted to the motor fixation element (110) and the rotational shaft (161) is fluid-tightly received by the second sealing surface (132) of the motor shaft seal (130).

12. The electric device (200) according to claim 11, wherein the motor fixation element (110) and the one or more through-slots (112) formed in the motor fixation element (110) have a higher deformability than the housing (170) of the electric device (200) in a direction from the rotational shaft (161) to the respective connection section, such that a lateral force applied to the rotational shaft (161) of the motor (160) to be mounted deforms the motor fixation element (110) and not the inner circumferential surface (171) of the housing (170).

13. A hair cutting device (300) comprising an electric device (200) according to any of claims 11 and 12, further comprising a cutting tool (310) drivingly connected to the rotational shaft (161) of the motor (160), wherein a main cutting direction of the cutting tool (310) is transversal to a straight line connecting the opposite first connection section (151) and the second connection section (152).

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