ES2946737T3 - Personal hygiene device with pivotable treatment head - Google Patents

Abstract

The present disclosure relates to a personal care device with a treatment head pivotally mounted about a pivot axis with respect to a body of the personal care device, the personal care device having a pin having a pin head, the pin is provided on one of the treatment head or body, a cam member having a cam surface that is provided on the other treatment head or body, a spring member that presses the head of the pin and the cam surface relative to each other, where the head of the pin is in contact with the cam surface and the cam surface has a shape that defines a rest position in which the elastic thrust force provided by the spring element with which the head of the pin and the cam surface are urged against each other has a minimum non-zero value, and in which a rotation of the head about the pivot axis causes the head of the pin move along the cam surface and the cam surface is further shaped such that the spring force pushing the pin head and the cam surface against each other increases with increasing angle of rotation . (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Personal hygiene device with pivotable treatment head

field of invention

The present application relates to a personal hygiene device having a treatment head arranged to pivot about a pivot axis with respect to a body of the personal hygiene device.

Background of the invention

Document EP 1372428 A1 generally describes an epilator having a head and a housing, where the head is mounted on the housing so that it can pivot about a rest position. A spring is mounted between the head and the housing, so as to cause the head to return to the rest position once it has been pivoted out of the rest position.

EP 3398737 A1 discloses a razor handle comprising an elongated body, a connector and a release mechanism. The release mechanism is configured to release the interchangeable razor blade cartridge from the handle of the razor. The razor handle further comprises a release trigger, offset from the connector in a longitudinal direction of the elongate body, and a transmission mechanism connecting the release trigger to the release mechanism. A push button, forming a release trigger, may be arranged to emerge through an opening in a mid-segment of the elongated body, midway between the leading end and the trailing end thereof. The push button may further be configured to move along the transverse axis Z of the elongate body, entering the elongate body when operated by a user to activate release of the interchangeable razor blade cartridge from the razor handle. The elongated body of the razor handle can internally accommodate a push rod. The push rod may be slidably supported in a sleeve attached within the elongated body, to mechanically connect the push button to the release mechanism. The push rod may comprise a rounded end configured to engage a sloped surface of the push button. The inclined surface can thus form a cam surface, and the rounded end of the push rod a cam roller, in a cam mechanism configured to convert a push button insertion movement along a transverse axis Z intersecting the longitudinal axis Y in a sliding movement of the push rod along the longitudinal axis Y to actuate the release mechanism.

Document US 2017/0282392 A1 describes a razor having a handle with an intermediate hinged joint between the cutting blade and the part of the handle held by a user. The hinge is made of flexible elastomeric memory material so that the razor head can be moved from an initial position to a displaced position and back to the initial position. The hinge has at least one undercut to reduce its thickness and facilitate movement of the head. The hinge is defined by the pivotal connection of a razor top and a razor bottom by means of a pivot joint defined by opposed projections extending from opposite sides of the top, which are received in junction depressions provided in a inner surface of forks. The lower part of the razor is made of elastic materials such as natural or synthetic rubber, plastic, silicone rubber or other flexible material, and therefore the upper part can be snapped onto the lower part by flexing. out of the yokes to allow the projections to enter the depressions and then pop out again to form a pivot joint. The lower part has a spring channel into which a coil spring can be inserted to elastically bias the joint into an initial position. A plunger sits between the spring and the top. More particularly, the plunger has an upper cam surface which bears against a cam surface at the top.

It is an object of the present description to provide a personal hygiene device having a head arranged to rotate about a rotatable axis with respect to a body of the device comprising an improved or at least alternative provision of a return force supply arrangement. .

Summary of the invention

According to one aspect, there is provided a personal hygiene device as defined in claim 1.

Brief description of the drawings

The present description is made more understandable by a detailed description of illustrative embodiments and by referring to the figures. in the figures

Fig. 1 is a representation of an illustrative personal hygiene device embodied as a hair removal device;

Fig. 2 is a representation of a detachable accessory for a personal hygiene device, the accessory shown partially cut open so that a spring-loaded pin and a cam member having a cam surface can be seen;

Fig. 3A is a detail in cross-sectional view of the spring-loaded pin and cam member shown in Fig. 2, where the spring-loaded pin is in a central or rest position;

Fig. 3B is a detail cross-sectional view of the spring-loaded pin and cam element, where the pin is in a pivoted position and the spring element is in a more compressed state;

Fig. 4A is a detail of a cross-sectional view of the spring-loaded pin guided in a pin holder; and

Fig. 4B is a detail of a cross-sectional view of the pin and pin holder shown in Fig. 4A taken on a plane A-A which is perpendicular to the cross-section of Fig. 4A, where the plane of view A-A is indicated in Fig. 4A.

Detailed description of the invention

In the context of the present description "personal hygiene" shall mean the nutrition (or care) of the skin and its appendages (i.e. hair and nails) and of the teeth and oral cavity (including the tongue, gums etc. ), where the objective is, on the one hand, the prevention of diseases and the maintenance and strengthening of health (“care”) and, on the other hand, the cosmetic treatment and improvement of the appearance of the skin and its appendages. It must include the maintenance and strengthening of well-being. This includes skin care, hair care and oral hygiene, as well as nail care. This also includes other grooming activities such as beard grooming, shaving and waxing. A “personal hygiene device” therefore means any device for performing this feeding or grooming activity, e.g. eg, (cosmetic) skin treatment devices such as skin massagers or skin brushes; wet razors; electric shavers or trimmers; electric epilators; and oral hygiene devices such as manual or electric toothbrushes, (electric) flossers, (electric) irrigators, (electric) tongue cleaners or (electric) gum massagers. This would not exclude that the proposed personal hygiene system may have a greater advantage in one or more of these fields of care or device than in one or more of the other areas. In the description below with reference to the figures, a hair removal device was chosen to present details of the proposed personal hygiene device. As long as the details are not particular to a hair removal device, the proposed technology can be used in any other personal hygiene device.

The present description relates to a personal hygiene device having a treatment head and a handle, where the treatment head is rotatable or pivotable relative to the handle about a tilting or pivoting axis. The treatment head has a rest position (which can also be called a central position in case the rest position is approximately central with respect to two tilt directions) from which the head can be tilted or pivoted in at least one direction angular against a return spring force provided by a spring element. The treatment head and the body are pushed against each other in the rest position by a pushing force that must be overcome in order to tilt the head out of the rest position. The bias force and the return force of the spring are provided by a spring element acting between a pin and a cam element, where the pin has a pin head that is in contact with a cam surface of the cam element. . The spring element pushes the head of the pin and the cam surface against each other with some non-zero minimum value (eg 2 N). Although it is mentioned here that the personal hygiene device has a spring element, this only means that one spring element is needed, but will not preclude the use of additional spring elements to provide the full return force of the spring. To pivot the treatment head about the pivot axis, the pushing force must first be overcome, and then the head of the pin slides on the cam surface if the applied force increases further. Thus, the push force provides good feedback to the user, since the push force must be overcome before the head will actually pivot. In the case where a spring only provides a return force, but no push force, pivoting begins once a force is applied. Without any limitation, the pushing force can generally be in a range between 0.5 N and 8 N, in particular in a range between 1.0 N and 5.0 N, more particularly in a range between 1 .5 N and 4.0 N, and even more particularly in a range between 2.0 N and 3.0 N. Without any limitation, the spring constant of the spring element can be in a range between 0, 05 N/mm and 1.0 N/mm, in particular in a range between 0.1 N/mm and 0.4 N/mm, and more particularly in a range between 0.15 N/mm and 0 .25N/mm. Although in the explained embodiments, the pushing force pushes the head of the pin against the cam surface, this does not exclude that the cam surface is pushed against the head of the pin, that is, when the cam element can move and the head of the pin can only pivot.

The cam surface has a particular shape so that the spring force applied by the spring element increases with increasing pivot angle. Here, the shape of the cam surface is such that the distance between the pivot axis and the cam surface decreases and therefore the pin is forced to move towards the pivot axis (or the cam element is forced away from the pivot axis) and by this movement the spring element is deforms so that the spring force with which the head of the pin is pushed against the cam surface is increased. In the case where the cam surface follows a circular function with respect to the pivot axis (i.e. the cam surface would be a part of the circle with the pivot axis being at the center of the circle), neither the pin nor the cam element would move, and the spring force would not change. The cam surface can follow any arbitrary function as a function of the pivot angle as long as the distance between the cam surface and the pivot axis increases essentially monotonically. The increasing spring force acts against the deflection of the treatment head and tries to return the treatment head to the rest position. The spring element may be a coil spring that compresses when the pin moves toward the toggle axis to increase the force of the spring. However, the spring element can also be a bending leaf spring, a twisting torsion spring, etc. As already mentioned, instead of one spring element, two or more spring elements can be used. The cam surface can be shaped in such a way that the distance between the cam surface and the pivot axis decreases linearly with the pivot angle. The cam surface can also be shaped so that any other distance-reducing function is achieved. This will not preclude the cam surface from providing one or more locking positions at locking pivot angles, where the pivot angle would be maintained without the applied external force.

Although in some embodiments, the treatment head can only pivot out of the rest position in one pivot direction, i.e., a clockwise or counterclockwise direction with respect to the rest position, the treatment head can, in some embodiments, pivoting in a plane in a clockwise direction and in a counterclockwise direction out of the rest position. The maximum clockwise pivot angle can have the same value as the maximum counterclockwise pivot angle (eg, 13 degrees). Alternatively, the maximum pivot angle can have different values in the clockwise and counterclockwise directions (eg, 6 degrees and 20 degrees). The personal hygiene device may comprise at least one stop element for mechanically limiting the deflection of the treatment head out of the rest position so that a maximum pivot angle cannot be exceeded. Two stop elements can be present in case the treatment head can pivot in a clockwise and counterclockwise direction.

The head of the pin has a contact surface for contacting the cam surface. The contact surface may be shaped to provide an essentially point-shaped or line-shaped contact region between the pin head contact surface and the cam surface. The contact surface of the head of the pin is shaped as a part of a sphere or a part of a cylinder. In some embodiments, the head of the pin is a cylinder or sphere that is particularly pivotally mounted to the pin. Such a design can help reduce friction between the contact surface of the head of the pin and the cam surface. The cam surface has a depression to define the rest position. The depression has a diameter smaller than the diameter of the head of the pin and in particular smaller than the size of the contact surface so that the contact surface of the head of the pin has two contact regions in the form of a point or in the form of a line with the cam surface in the rest position. In particular, the depression can begin and end at the contact points or contact lines of the contact surface of the head of the pin with the cam surface. This leads to a better defined home position and evens out the tolerances.

Since the pin moves in some embodiments in a linear direction towards (and away from) the pivot axis depending on the pivot direction, the pin can be guided by any suitable linear bearing which, in particular, pivots together with the pin. In some embodiments, the pin is guided into a recess in a pin support, the pin support providing a sliding bearing. Pin and pin holder materials can be chosen to allow self-lubrication. Although it is possible to fabricate the pin and pin holder by machining a metal block, plastic block or ceramic block to a very close tolerance so that the inner bore of the pin holder can accurately receive the pin, it may be less expensive to make at least the hollow pin holder from a thermoplastic material so that the hollow pin holder can be manufactured by plastic injection molding, where many pin holders can be manufactured in parallel and with a low cycle time. The gap in such an injected pin holder can then have a different shape from that of the pin. For example, the pin may have a circular cross section and the hole in the pin holder may have a polygonal cross section, e.g. eg, a hexagonal cross section. In some embodiments, the pin holder has at least two guide surfaces, in particular oppositely arranged, which guide the pin. Additionally, the pin holder may have at least four guide surfaces where two guide surfaces are arranged in a first longitudinal position and two guide surfaces are arranged in a second longitudinal position, respectively. By such an arrangement, the pin is guided in two positions along its longitudinal extension, which leads to precise linear guidance and aids in the design of the pin holder since the pin holder does not need to guide the pin along. along its entire length inside the pin bracket. The hole in the pin holder can be made as a blind hole. Instead of a pure blind hole, the hole can continue as a smaller diameter hole that can be used in the step of mounting the spring element.

The spring element can be arranged, at least partly, in a hole in the pin where the hole in the pin can be concentric with the longitudinal axis of the pin. The spring element can generally be embodied as a spiral spring. One end of the spring element can bear against a bearing surface in the recess in the pin and a second end of the spring element can bear against a bearing surface in the hollow of the pin holder. The bearing surface on the pin holder can be precisely sized to snugly receive the second end of the spring element such that the second end of the spring element cannot move relative to the pin holder. The bearing surface in the pin holder may be provided by a recess in the pin holder. As already indicated, the hole can continue as a hole of smaller diameter. A metal pin can be slid through the smaller diameter hole, in which the spring element (eg, coil spring) can be mounted until the pin that compresses the spring element mounts in the gap. The metal pin can be retracted from the smaller diameter hole once assembly of the pin and spring element has occurred.

The gap in the pin holder can be defined by a precisely machined core in the plastic injection molding of the pin holder. In particular, the guide surfaces (ie the distance between the guide surfaces) of the recess can then be realized with high quality, e.g. For example, a tolerance of ±0.03 mm can be applied for the guide surfaces. The same or similar low tolerance can be applied for the respective cooperating outer surface portions of the pin itself, so that the pin is ultimately guided with high precision and with little play or play.

The head of the pin or the cam element can be made, at least in the area of the contact surface of the pin or the cam surface, of one of the following materials: a plastic material, in particular a hard plastic material having a Shore D hardness of at least 40, further in particular a reinforced plastic material; a light metal or a metal alloy having a specific gravity in the range of 2 g/cm3 to 5 g/cm3 such as titanium or aluminum; a heavy metal or a metal alloy having a specific gravity in the range of 5 g/cm3 to 20 g/cm3 such as steel, brass or bronze; or a ceramic material such as silicon carbide or tungsten carbide.

Fig. 1 is a representation of an illustrative embodiment of a personal hygiene device 1 realized as a mechanical epilator. The personal hygiene device 1 comprises a removable accessory 10 and a handle 20. The removable accessory 10 comprises a treatment head 100 which is arranged to be pivotable with respect to a body 200 of the personal hygiene device 1 about an axis A of pivoting so that the treatment head 100 can pivot in a clockwise direction and in a counterclockwise direction about the pivot axis A as indicated by the double arrow R1. The treatment head 100 is here embodied as an epilation head comprising a treatment head housing 101 and a treatment unit 120 embodied as a mechanical epilation cylinder. In the example shown, the treatment head 100 comprises a skin contact element 110 which is arranged to be pivotable about a pivot axis S as indicated by the double arrow R2. The pivot axis S is aligned with a central axis of the rotatable mechanical hair removal cylinder 120 . The additional pivotable skin contact element 110 is an optional feature. A neck 180 is fixedly connected to the head housing 101 of the treatment head. Neck 180 is arranged to plunge into frame 190 when treatment head 100 is pivoted about pivot axis A. In the shown embodiment, the frame 190 is a part of the detachable accessory 10 but is fixedly secured to the handle 20 in the attached state, in particular with a mechanical fastening means such as one or more snap hooks. Thus, although frame 190 is part of detachable attachment 10, it is fixedly secured to handle 20, that is, it does not pivot or move when the treatment head is moved, and handle 20 and frame 190 together form the body 200 of the personal hygiene device 1. In another embodiment, only the treatment head can be made as a detachable accessory and the frame and neck are provided on the handle. In another embodiment, the treatment head together with the neck form the detachable accessory and the frame is made as a part of the handle.

The handle 200 has a handle housing 201 that can accommodate a rechargeable battery or accumulator and a control unit for operating the treatment unit 120. In some embodiments, the treatment unit is not powered and can only be powered by electrical power. In some embodiments, the treatment unit is powered and powered. In some embodiments, the treatment unit is not actively powered or powered. The handle 200 may comprise one or more switches 210 such as an on/off switch or a mode switch, etc. The handle may comprise any other features that a skilled person would provide in a handle, e.g. eg, a light source 220 to illuminate the area to be treated.

Fig. 2 is a representation of an illustrative partially open removable fitting 10A comprising a treatment head 100A having a treatment head housing 101A to which a neck 180A is fixedly mounted. A frame 190A is pivotally arranged with respect to treatment head 100A and neck 180A. A support frame 170A is mounted to the frame 190A. The support structure 170A and/or the frame 190A have coupling means for coupling the detachable accessory 10A to a handle of a personal hygiene device as explained with respect to Fig. 1. The support structure 170A carries an element 150A cam. A pin unit 160A is fixedly mounted to the treatment head 100A and/or neck 160A. The pin unit 160A comprises a pin holder 161A and a pin 165A, where a pin spring element 169A is arranged between the pin holder 161A and the pin 165A. The pin 165A contacts a cam surface 151A of the cam member 150A. The pin 165A is shown here in a rest position. The spring element 169A, which is embodied here as a spiral spring, compresses and thus pushes the pin 165A against the cam surface 151A of the cam element 150A with a predetermined bias force F. The technical design of the pin unit 160A and the interaction between the pin 165A and the cam element 150A will be explained in more detail below with reference to Figures 3A, 3B, 4A and 4B. As mentioned above, although the embodiment explained with respect to the figures shows a spring-loaded pin, it is also contemplated that the cam element is spring-loaded, and that the cam element can be guided by a linear guide.

Fig. 3A is a detailed cross-sectional view of the pin unit 160A and the cam member 150A when the pin 165A is in a rest position. As already explained, the pin unit 160A comprises a pin holder 161A having a gap 162A, which will be described in more detail with reference to Figures 4A and 4B, a pin 165A arranged partially in the gap 162A and a locking element 169A. spring urging a pin head 166A against a cam surface 151A of the cam member 150A with a biasing force F. The pin 165A has a central hole or hole 167A in which the spring element 169A is arranged. The spring element 169A is here embodied as a spiral spring, which will not exclude another embodiment, e.g. For example, the spring element can be an elastically deformable flexible rubber element. One end 1692A of the spring element 169A bears on a bearing surface 1651A provided in the recess 167A.

Pin head 166A has an outer contact surface 1661A that makes frictional contact with a cam surface 151A. The cam surface 151A of the cam member 150A defines a rest position of the pin unit 160A. To pivot the pin unit 160A out of the rest position, the pin head 166A must move along the cam surface 151A, which is shaped such that the pin 165A will move toward a pivot axis R. with an increasing pivot angle as shown in Fig. 3B, which leads to a compression of the spring element 169A and thus to an increase in the force F with which the pin head 161A is pushed against the cam element 150A. The cam element 150A has a depression 152A which is arranged centrally in the cam element 150A, that is, it is arranged centrally with respect to an axis L1 defining the rest position. Without the central depression 152A, the right lateral cam surface and the left lateral cam surface would meet at an acute angle. The contact surface 1661A of the pin head 166A is cylindrical at least in those areas that contact the cam surface 151A. The size of the depression 152A is smaller than the extension of the contact surface 1661A of the pin head 166A so that the pin head 166A contacts the cam member 150A at two contact points CP1 and CP2 a the left and right of the depression 152A (since the cam surface 151A and the contact surface 1661A extend in three-dimensional space, the contact points CP1 and CP2 are essentially contact lines or contact areas but, for simplicity, here they are called contact points). In particular, the depression 152A is dimensioned so that the contact points CP1 and CP2 lie right on the edge of the depression 152A. The depression 152A tends to even out the tolerances in the parts.

In the shown embodiment, the cam member 150A and the cam surface 151A are symmetrical with respect to the home position so that the home position is also a center position. In order to prevent the pin head 166A from pivoting about one end of the cam element 150A, the personal hygiene device may comprise stop elements that prevent any pivoting beyond a maximum pivot angle. The personal hygiene device may comprise two such stop elements, where one stop element limits the range of pivoting in the clockwise direction and the other stop element limits the range of pivoting in the counterclockwise direction, where the clockwise and counterclockwise directions intersect. defined with respect to the plane of the paper. Although the cam element 150A is here symmetrical, the stop elements can provide non-symmetrical ranges of clockwise and counterclockwise pivoting.

The pin 165A may comprise an extension that is arranged in a slot or notch in the pin bracket 161A (or vice versa) so that the pin 165A is secured in the pin bracket 161A during the mounting process.

A somewhat larger detail of the pin unit 160A and the cam member 150A is shown in Fig. 3B, where the pin unit 160A is shown in a clockwise pivoted state. The direction of longitudinal extension of the pin unit 160A is indicated by the axis L2, which pivots against the home position axis L1 at a pivot angle a. As the pin unit is secured with respect to the treatment head, the shown pivoting state of the pin unit 160A means that the treatment head is likewise pivoted by the pivot angle a against the body of the personal hygiene device. The pivoting occurs around a pivot axis R which is defined by a bearing and/or a joint pivotally connecting the treatment head and the body of the personal hygiene device, e.g. For example, the treatment head and the body can be pivotally connected by means of a universal joint. The contact surface 1661A of the pin head 166A is in contact with the cam surface 151a at a contact point CP3. The contact point CP1 on the contact surface 1661A of the pin head 166A shown in Fig. 4A moves slightly when the pin 165A is pivoted out of the rest position. Obviously, the head 165A of the pin has only one point CP3 of contact with the cam element 150A once it is pivoted out of the rest position. The cam surface 151A is shaped such that the distance D(a) between the contact point CP3 and the pivot axis R monotonically decreases with increasing pivot angle a. Due to this decrease in the distance D(a), the pin 165A moves towards one end of the blind hole of the recess 167A of the pin holder 161A and, as a consequence, the spring element 169A is compressed, which leads to an increase by the force F2 with which the pin head 166A is pushed against the cam element 150A. This increasing push force results in a return force that attempts to return the pin unit 160A back to its home position. An end 1961A of the spring element 169A opposite the end 1692A bears on a bearing surface 1631A which is provided in a recess 163A provided in the blind hole end of the recess 162A of the pin holder 161A. The recess 163A is dimensioned such that the end 1961A of the spring element 169A is essentially snugly received in the recess 163A and therefore cannot move.

As said, the cam surface is formed in a manner that results in a monotonic decrease in the distance D(a) between the contact point CP3 and the pivot axis R with increasing pivot angle a. In some embodiments, the mathematical relationship can be expressed by a linear equation:

D(a) = D0 - k-a,

where D0 is the distance at rest and k is a slope factor that defines how fast the distances decrease per pivot angle, that is, k = AD/Aa. This, of course, should not exclude that the cam surface may take other shapes, ie a shape where the distance potentially decreases or a shape that supports an intermediate locking position at a locking angle.

The materials from which the pin head 166A is made at least in the area of the contact surface 1661A and the cam element 150A at least in the area of the cam surface 151A can be chosen such that the friction between the two parts does not lead to a self-blocking. In particular, the coefficient of friction between the two materials can be chosen below 0.4, in particular below 0.35, such as 0.3 or 0.25 or 0.2. As said in a previous paragraph, the head of the pin can be made as a cylinder or a sphere that is pivotally mounted on the pin, and therefore self-locking problems can be overcome.

Generally, it is not excluded that the pin fits smoothly in the pin holder. For example, the pin and pin holder may be precisely shaped pieces of aluminum or the like and may be lubricated with a suitable lubricant. With reference to Figures 4A and 4B, an illustrative embodiment of the pin unit 160A is explained, comprising the pin 165A and the pin support 161A that allows the parts to be made by plastic injection molding, where the tolerances are greater than in a metal forming process and where the manufacturing process imposes certain needs such as deformation angles that are accommodated by design. In this embodiment, the pin 165A and the pin holder 161A are not made as smoothly fitting parts, but still a good quality of guiding the linear movement of the pin 165A is achieved. Fig. 4A is a cross-sectional detail of the pin unit 160A and Fig. 4B is another cross-sectional detail of the pin unit 160A taken along the plane A-A as indicated in Fig. 4A.

The pin unit 160A comprises the pin holder 161A, the pin 165A and the spring element 169A. With respect to the spring element 169A, reference is made to the above paragraphs. The pin 165A is guided by the pin support 161A. The pin holder 161A has a recess 162A made as a hole having a blind hole end 164A. As can be seen in Fig. 4A, the gap 162A in the pin holder 161A tapers from its open end at the front of the pin holder 161A where the pin 165A protrudes towards the cam member 150A to the hole end 164A. blind. This taper is necessary to allow pin support 161A to deform from a core defining gap 162A at the end of a plastic injection molding process. Instead of a uniform taper from the front to the end of the blind hole 164A, the angle of incidence varies over the longitudinal extension length of the hole 162A. From the front to the blind hole end 164A, the angle of incidence is first very small in a front region 1611A, then the angle of incidence is relatively large in a central region 1612A, and the angle of incidence becomes very small from again in a blind hole end region 1613A. In the regions 1611A and 1613A with the low angle of clearance, guide surfaces having a low specified tolerance are provided. In the region 1611A, which is in longitudinal extension direction located near the front part of the pin holder 161A, two oppositely arranged guide surfaces GS21 and GS22 are provided. In the region 1613A, which is in longitudinal extension direction located near the blind end hole 164A of the pin holder 161A, two oppositely arranged guide surfaces GS11 and GS12 are provided.

Pin 165A also generally tapers from a front end region 1653A to a trailing end region 1654A. But as described for the hole 162A of the pin holder 161A, the pin 165A has areas of low tolerance at the front and at the back that coincide in the assembled state with the longitudinal locations of the guide surfaces in the hole 162A. . As best seen in Fig. 4B, the pin 165A has an essentially circular cross-sectional outer shape and the gap 162A has an essentially hexagonal cross-sectional inner shape. Therefore, the guiding surfaces, of which GS11 and GS12 are shown in Fig. 4B, provide essentially line-shaped guiding contact with the pin. 165A. The non-guiding surfaces NGS11 to NGS14 are provided with a nominal pin distance 165A. The same type of arrangement is provided in the frontal region 161A. This leads to precise guidance of the movement of the pin in the z-direction (where the z-direction is indicated in Fig. 4A) and precise location of the pin 165A in the x-direction. The contact of the pin 165A with the cam member 150A prevents the pin 165A from tilting and only allows some freedom of movement in the y-direction (the y-direction is indicated in Fig. 4B).

The dimensions and values described herein are not to be construed as being strictly limited to the exact numerical values stated. Rather, unless otherwise specified, each such dimension is intended to mean both the named value and a functionally equivalent range around that value. For example, a dimension described as "40mm" is intended to mean "about 40mm".

Claims (14)

Yo. A personal hygiene device (1) with a treatment head (100) that is pivotally mounted about a pivot axis (A) with respect to a body (200) of the personal hygiene device (1), comprising the personal hygiene device (1): a pin (165A) having a pin head (166A), the pin (165A) being provided on one of the treatment head (100) or the body (200); a cam member (150A) having a cam surface (151A) that is provided on the other of the treatment head (100) or the body (200); a spring element (169A) that pushes the head (166A) of the pin and the cam surface (151A) against each other; wherein the head (166A) of the pin is in contact with the cam surface (151A) and the cam surface (151A) is shaped so as to define a rest position in which the biasing spring force provided by the pin spring element (169A) with which the head (166A) of the pin and the cam surface (151A) are pushed against each other has a non-zero minimum value; wherein a pivoting of the head (100) about the pivot axis (A) causes the head (166A) of the pin to move along the cam surface (151A) and the cam surface (151 A) is further shaped such that the spring force (F) pushing the pin head (166A) and the cam surface (151A) against each other increases with increasing pivot angle (a); and characterized by the head (166A) of the pin has a contact surface (1661A) for contacting the cam surface (151A), said contact surface (1661A) is at least a part of a spherical surface or a cylindrical surface and the cam surface (151A) has a depression (152A) to define the rest position, the depression (152A) being smaller than a diameter of the sphere defining the spherical surface or of the cylinder defining the cylindrical surface and the diameter being depression (152A) smaller in diameter than the diameter of the head (166A) of the pin and being smaller than the size of the contact surface (1661A), so that the contact surface (1661A) of the head (166A) ) of the pin has two point-shaped or line-shaped contact regions (CP1, CP2) with the cam surface (151A) in the rest position. The personal hygiene device according to claim 1, wherein the pin (165A) is guided in a recess (162A) of a pin holder (161A). The personal hygiene device according to claim 2, wherein the pin holder (161A) has at least two guiding surfaces (GS21, GS22) for guiding the pin (165A), in particular the pin holder (161A). has at least four guiding surfaces (GS11, GS12, GS21, GS22) where two oppositely arranged guide surfaces are provided in a first longitudinal position (1611A) on the pin holder (161A) and two oppositely arranged guide surfaces opposite shape are arranged in a second longitudinal position (1613A). The personal hygiene device according to claim 2 or claim 3, wherein the pin part guided by the pin holder (161A) has an essentially circular cross-sectional shape and a part on the pin holder (161A) for guiding the pin it has an essentially polygonal cross-sectional shape, in particular a hexagonal shape. The personal hygiene device according to one of claims 3 to 4, wherein the pin holder (161A) and the pin guided parts (165A) have at least in the area where the pin (165A) is guided by the pin bracket (161A) a tolerance of ±0.03 mm or less. The personal hygiene device according to one of claims 2 to 5, wherein the spring element (169A) is arranged partly in a longitudinally extending central recess (167A) in the pin (165A) and partly in the recess (162A) from the pin support (161 A). The personal hygiene device according to one of the claims 2 to 6, wherein the spring element (169A) is a longitudinally extending spiral spring having a first end (1691A) which is arranged in a recess (163A ) of the pin support (161A), the recess (163A) being sized to confine the first end (1691A) so that the first end (1691A) is essentially immovable. The personal hygiene device according to one of claims 1 to 7, wherein the cam surface (151A) has a generally concave shape tapering towards the cam surface portion defining the rest point, in particular at where the cam surface (151A) is shaped symmetrically with respect to the rest position. The personal hygiene device according to one of the claims 1 to 8, wherein the cam surface (151A) is defined by a function with respect to the pivot axis which is given by the formula D(a) = D0 - AD (a/Aa), where D is the distance of a point (CP1; CP2) of contact of the head (166A) of the pin and the surface (151A) of the cam to the pivot axis (A), a is the angle of pivoting with respect to the rest position, D0 is the respective distance in the rest position, and AD and Aa are parameters that define the slope of the function. The personal hygiene device according to one of claims 1 to 9, wherein at least the head (166A) of the pin is made of one of the following materials: a plastic material, in particular a hard plastic material having a hardness Shore D of at least 40, also in particular a reinforced plastic material; a light metal or a metal alloy having a specific gravity in the range of 2 g/cm3 to 5 g/cm3 such as titanium or aluminum; a heavy metal or a metal alloy having a specific gravity in the range between 5 g/cm3 and 20 g/cm3 such as steel, brass or bronze. The personal hygiene device according to one of claims 1 to 10, wherein at least the cam surface (151A) is made of one of the following materials: a plastic material, in particular a hard plastic material having a hardness Shore D of at least 40, more in particular a reinforced plastic material; a light metal or a metal alloy having a specific gravity in the range of 2 g/cm3 to 5 g/cm3 such as titanium or aluminum; a heavy metal or a metal alloy having a specific gravity in the range of 5 g/cm3 to 20 g/cm3 such as steel, brass or bronze; a ceramic material such as silicon carbide or tungsten carbide. The personal hygiene device according to one of the claims 1 to 11, wherein the spring constant of the spring element (169A) is in the range of 0.05 N/mm to 1.0 N/mm, in particularly in a range between 0.1 N/mm and 0.4 N/mm, and more particularly in a range between 0.15 N/mm and 0.25 N/mm. The personal hygiene device according to one of claims 1 to 12, wherein the pushing force (F) with which the head (166A) of the pin is pushed against the cam surface (151A) increases from the central position to a maximum pivot angle position by a factor in the range of 1.025 to 1.5, in particular in the range of 1.05 to 1.25, and more particularly in the range of 1.08 to 1.15. The personal hygiene device according to one of claims 1 to 13, wherein the pushing force (F) with which the head (166A) of the pin is pushed against the cam surface (151A) in the rest position is in the range between 0.5 N and 8 N, in particular in a range between 1 N and 5 N, more particularly in a range between 1.5 N and 4.0 N, and still more in particular in a range between 2.0 N and 3.0 N.