Brush, especially toothbrush

Abstract

The present invention relates to a brush, in particular a toothbrush (2), which is produced using a low amount of plastic but is nonetheless sufficiently rigid and strong. The brush has a brush body (4) with a handle stem (20), a brush head (10) forming a substantially planar brush head surface (12), and a brush neck (14) provided between the handle stem (20) and the brush head (10). The brush also has elongate cleaning means (6) which protrude from the brush head surface (12) at a front side (V) of the brush body (4). The rigidity is achieved by the handle stem (20) having a handle-stem portion (22) with a T-shaped cross-section.

Description

[0001] Brush, especially toothbrush

[0002] The present invention relates to a brush, in particular a toothbrush, comprising a brush body. The brush body has a handle and a brush head, which forms a substantially planar brush head surface, and a brush neck provided between the handle and the brush head. The brush further comprises elongated cleaning elements that project from the brush head surface at a front face of the brush body.

[0003] Such a brush is commonly known as a toothbrush.

[0004] For example, WO 2023 / 232822 A1 discloses a toothbrush with the general characteristics described above. Its handle is provided with a hollow structure located within the handle, with a view to using the plastic that forms all or part of the brush head in the most resource-efficient way possible.

[0005] Brushes, especially toothbrushes, must meet various requirements. First and foremost, they must maintain an aesthetically pleasing and hygienic appearance even after prolonged use. This means that undercuts, ridges, and crevices where bacteria and dirt can accumulate are unacceptable.

[0006] The present invention is based on the problem of providing a brush of the type mentioned at the outset that meets the hygienic and strength requirements, but which can be manufactured with minimal material usage.

[0007] To solve this problem, the present invention further develops a brush of the type mentioned above by means of a handle with a T-shaped handle section in cross-section. The T-shaped handle section has a high area moment of inertia with minimal material usage. A T-shaped handle section in cross-section has a transverse web and a longitudinal web, which typically extends perpendicular to the transverse web. The longitudinal web is typically designed to extend in a longitudinal plane of the brush body, which extends transversely to a transverse plane. This transverse plane extends parallel to the plane containing the brush head surface, which is hereinafter referred to as the brush head surface plane. The transverse web and the longitudinal web are optimally designed with regard to the desired area moment of inertia. The transverse web contributes in particular to the bending stiffness of the brush body in its longitudinal direction.The brush body is typically a longitudinally slender, rod-shaped body. The crossbar stiffens this elongated brush body in a direction perpendicular to its length. The interconnected crossbars increase the overall torsional stiffness of the brush body. The brush body may have a cross-sectional shape that, in cross-sectional view, does not significantly exceed the cross-sectional contour of a conventional, essentially circular or elliptical brush body. However, because recesses projecting inwards from the free end face of the longitudinal rib are provided opposite the maximum extent of the crossbar, the brush body, and especially the handle, requires less material while maintaining essentially the same strength as a brush body with a circular or elliptical cross-section.

[0008] For ergonomic reasons, it is preferable to orient the T-shaped handle section so that the crossbar extends in a plane parallel to the brush head surface, and the longitudinal rib extends centrally from the crossbar to the front of the brush body. The front of the crossbar is therefore located on the same side of the handle as the brush head surface. The crossbar rests beneath the handle within its T-shaped section. This allows the brush, when held in the user's hand, to rest against the crossbar, providing relatively broad and comfortable support. The comparatively narrower longitudinal rib allows the user to comfortably hold and clamp the brush in their hand.

[0009] The brush body, preferably the brush as a whole, is preferably made of plastic. The brush body, preferably the brush as a whole, can be made from a single plastic component.

[0010] The aforementioned end face is preferably formed by a cushion-like body made of a soft, elastic second plastic. This provides a more pleasant tactile feel despite the relatively small contact area for parts of the hand. Preferably, this second soft, elastic plastic, due to its lower strength compared to a conventional first hard component made of PP, PA, PBT, ABS, SAN, or PE, comprises no more than 40% of the area of ​​the T-shaped handle section in a cross-sectional view.

[0011] Alternatively, the cushion body is formed from a second rigid component, which can be either the same as the first or different. This gives the handle additional stability while maintaining its distinctive color appearance. If the same material is chosen for both components, better material recycling is possible.

[0012] The end face typically extends longitudinally along the handle in a plane parallel to the plane containing the brush head surface. The free end face of the longitudinal rib is typically located on the rear side of the brush. The rear side is formed by the side parallel to the surface of the brush head penetrated by the cleaning elements, this surface of the brush head being part of a front end face of the brush body. The aforementioned first hard component and the second plastic forming the cushion body, which may be made of a soft-elastic plastic component, are preferably the only materials used to form the T-shaped handle section, and more preferably to form the brush body.The T-shaped handle section, preferably the brush body, is formed solely by the cushion body and an associated base body made of the hard component. To further increase the area moment of inertia and also to ensure the best possible bonding of the soft elastic plastic, the T-shaped handle section forms flank surfaces extending from a rear end face, which are formed partly by the base body and partly by the cushion body. It is understood that the transition between the area formed by the hard component and the area formed by the soft elastic plastic is free of any steps or protrusions on the outside. Rather, the base body and the cushion body merge seamlessly and flush at an end surface that tapers to a point in cross-section. On the inside, the tapered end surfaces formed by the base body create a recess that accommodates the cushion body.In this way, the soft elastic plastic can be formed with a relatively large height and good volume below the front face which forms a contact surface for the hand, while at the same time the tapered end surfaces made of the material of the base body can be formed with relatively high inertia and torsional stiffness.

[0013] To increase rigidity and also to ensure good tactile properties, the T-shaped handle section, as seen from above on the brush head surface, is preferably designed with convex side edges. The T-shaped handle section typically has only such convexly curved side edges.

[0014] In a view orthogonal to the top view, namely a side view of the handle, the crossbar has essentially the same height, at least over its predominant longitudinal extent, and thus over the longitudinal extent of the handle. The height is the distance between the surface and the underside of the crossbar. Crucially, a reference line extending orthogonally to the longitudinal plane and tangent to the front and rear surfaces of the crossbar is decisive, preferably in an externally visible area.

[0015] The crossbar is provided at least towards the end and over at least 60%, preferably 70%, of the length of the handle, with essentially the same height. In a front area of ​​the handle oriented towards the brush head, where it may transition into a support area, the height can increase continuously along its length from the rear end to the front.

[0016] With B representing the width of the grill handle and thus the greatest extent of the transverse web in its longitudinal direction, and with H representing the height of the grill handle, i.e., the extent perpendicular to the width and corresponding to the greatest extent of the longitudinal web, the resulting B / H ratio is between 0.5 and 2, preferably 0.8–1.8, and particularly preferably 1.0–1.7. According to a preferred embodiment, the corresponding ratio lies in an interval between 1.1 and 1.3, preferably between 1.15 and 1.28, at least for the majority of the length of the grill handle. Only in one end region of the handle can the ratio lie between 1.3 and 1.5.

[0017] Preferably, the transverse web has a convex cross-sectional shape in a cross-sectional view. The cross-sectional shape can be an ellipse or a rectangle with rounded end faces. The cross-sectional shape is usually axially symmetric to the longitudinal plane. Since the longitudinal web adjoins the transverse web directly and forms an integral unit with it, this means that parts of the boundary surface of the transverse web also form a boundary surface of the longitudinal web and are therefore not exposed on the outer surface of the cross-sectional profile.

[0018] According to a further preferred embodiment of the present invention, the longitudinal web has the flank surfaces mentioned above. In the further development discussed here, the longitudinal web forms these flank surfaces between its rear end face and the transverse web. In this preferred embodiment, the flank surfaces are inclined outwards at an angle of 1° to 60°, preferably between 1° and 45°, and particularly preferably between 1° and 35°, relative to the longitudinal plane. The flank surfaces can have a straight cross-section. Alternatively, they can be wholly or partially convex or concave. Preferably, the flank surfaces transition into the rear end face via a convex curve. The transition between each flank surface and the transverse web is typically concave.

[0019] According to a preferred embodiment of the present invention, a bearing area is formed by the brush body between the handle and the brush neck. In a top view of the brush head surface, this bearing area is wider than the brush neck to form a bearing surface. In this top view, the bearing area typically has strictly convex lateral edges. There is usually a waist-like section between the bearing area and the handle. In this top view, the brush neck seamlessly follows the contour of the bearing area, but essentially forms the waist and then the thinnest section at the transition between the brush neck and the brush head. Preferably, the bearing surface is bordered. This border is preferably formed by the first rigid component. Surrounded by the border, preferably completely surrounded, the bearing surface is formed from the soft, elastic second plastic.On the front side, opposite the brush head surface, the brush neck initially extends from the contact area in a concave cross-section. In a side view, the brush body is preferably bent at the level of the contact area. Thus, the handle extends essentially parallel to the brush neck, but the handle is raised forward at the bend, towards the brush head surface.

[0020] In a side view, the handle is preferably convexly curved forwards. The opposite back side of the handle can be partially or completely concave and / or partially straight or completely straight.

[0021] Preferably, the handle forms an end section at its end opposite the brush head. In this end section, the transverse rib and the longitudinal rib merge into one another, so that the T-shaped cross-section is dissolved as one approaches the opposite end.

[0022] Further details and advantages of the present invention will become apparent from the following description of two exemplary embodiments in conjunction with the drawing. In this drawing, we see...

[0023] Figure 1 shows a rear view of a first embodiment;

[0024] Figure 2 shows a front view of the first embodiment without cleaning agent;

[0025] Figure 3 shows a side view of the first embodiment;

[0026] Figure 4 shows a perspective rear view of the first embodiment;

[0027] Figure 5 shows a sectional view along line VV as shown in Figure 4;

[0028] Figure 6 shows a side view according to Figure 3, illustrating different section planes, to which section views in Figure 3 refer.

[0029] Figures 7A-A to 1ll show: and

[0030] Figure 8 shows a perspective rear view of a second embodiment.

[0031] In the drawing, reference numeral 2 denotes a toothbrush with a brush body 4 and cleaning agents 6, which are not shown in Figures 1 to 5, but are shown in Figure 6. In this embodiment, these cleaning agents 6 are formed as bristle bundles 8. These bristle bundles 8 consist of a plurality of bristle filaments that are connected to the brush body 4 via a metallic anchor or other fastening means.

[0032] The brush body 4 has a brush head 10 at its front end, which forms a substantially planar brush head surface 12 through which the bristle bundles 8 protrude. A brush neck 14 extends behind the brush head 10. The transition to the brush head 10 is shown in detail in the top views of Figures 1 and 2, and the neck widens slightly conically towards the rear. This brush neck 14 transitions into a support area 16, which, in the top view of Figures 1 and 2, is at least as wide as the brush head 10. On the side of the support area 16 opposite the brush neck 14, it transitions via a waist 18 into a handle 20. The handle 20 consists of a T-shaped handle section 22 and an end section 24, which also forms the end of the brush body 4 opposite the brush head 10.

[0033] As Figures 4 and 5 illustrate, this T-shaped handle section is characterized by a cross-sectional geometry defined by a longitudinal rib 26 and a transverse rib 28. The longitudinal rib extends along a longitudinal plane L, which, at least in a cross-sectional view, intersects the brush head surface 12 at right angles. Accordingly, the longitudinal rib 26 also extends at right angles to the brush head surface 24. The transverse rib 28 extends transversely to the longitudinal rib 26. The longitudinal rib 26 and the transverse rib 28 merge into each other in the cross-sectional direction.

[0034] In Figure 5, a transverse plane is shown with reference numeral Q, defining the central longitudinal axis of the transverse web 26 and extending perpendicular to the longitudinal plane L. In the illustrated embodiment, the transverse web 28 has an overall convex outer circumferential surface. It is understood that this surface transitions seamlessly into the longitudinal web 26, at least towards the front. There, the longitudinal web 26 forms flank surfaces 30, which extend between a rear end face 31 formed by the longitudinal web 26 towards the front and the transverse web 28. The flank surfaces 30 each transition via a convex curvature at reference numeral 34 into the rear end face 31 and via a concave curvature at reference numeral 36 into the outer surface of the transverse web 28, which forms a front end face 32.

[0035] In Figures 1 to 5, reference numeral 40 denotes a base body made of a first rigid component, such as polypropylene (PP). Reference numeral 42 denotes a cushion body made of a second plastic, for example, a soft elastic elastomer (e.g., TPE). In this case, the base body is colored white, whereas the cushion body is a different color. The cushion body 42 has a significantly lower hardness and therefore higher elasticity.

[0036] As Figure 5 illustrates, the base body 50 partially forms the flank surfaces 30, which are mirror-symmetrical to the longitudinal plane L, just as the entire cross-section is axially symmetrical to this longitudinal plane L. A lower section of the flank surface 30 is formed by the base body 40. This tapers conically towards the rear to form pointed end surfaces 44. A recess 46 is shown between the pointed end surfaces 44 in the cross-sectional view of Figure 5. It is understood that the cushion body 42 is formed by overmolding the second component against the base body 40 and is thus connected to it. Despite being formed by two different bodies 40 and 42, the flank surfaces 30 are flat and without steps.

[0037] As Figure 5 illustrates, the cushion body 42 is shaped with a relatively large thickness parallel to the direction specified by the longitudinal plane L due to the recess 46 and accordingly has good spring properties for part of the hand resting on this cushion body 42.

[0038] Within the contact area 16, a contact surface 48 is formed by this cushion body 42. As Figure 5 illustrates, this contact surface 48 is surrounded by a circumferential edge 50 formed by the base body 40. In the front view according to Figures 1 and 2, the contact area 16 with its strictly convex side edges 52 can be seen. On the front side shown in Figure 2, the soft elastic material forming the cushion body 42 forms several lamellae 54 surrounding the hard component of the base body 40. These lamellae terminate at the same height as the material of the base body 40, which is provided between the lamellae 54. The lamellae 54 are joined laterally at the brush body 4 and merge into the cushion body 42; compare Figure 3 in conjunction with Figures 1 and 4. The lamellae define a thumb stop area 55.

[0039] As shown in Figure 2, the handle 20 has strictly convex curved side edges 56 that merge into the side edges 52 of the support area 16.

[0040] Figure 3 shows the height of the crossbar 28, denoted by H. This height is constant along the main longitudinal extent of the handle 20. Only a front section of the crossbar 28, extending towards the support area 16 and comprising no more than 35% of the longitudinal extent of the crossbar 28, widens in height up to the waist 18, as illustrated in Figure 3 by the heights Hi to H4.

[0041] Figures 4 and 5 further show that the brush neck 14 on the back of the brush body 4 initially extends from the support surface 48 towards the brush head 10 in a concave shape 58. The circumferential edge 50 transitions into a ridge 60, which separates the side surface of the brush neck 14, visible in Figure 3, from the back surface, visible in Figures 1, 4 and 5, and defines the concave shape 58.

[0042] Finally, reference numeral 62 indicates a bend in the brush body 4, visible in Figure 3. The handle 20, which extends essentially parallel to the brush neck 14, is offset forward at this bend 62. The bend 62 is limited to the longitudinal extent of the support area 16. All sectional views of the handle 20 in Figures 7A-A to 71 show the previously discussed T-shaped cross-section, the longitudinal extent of which is greater in the middle region of the handle 20 than at the respective ends. The varying height is primarily provided by the first plastic component, and thus the base body 40, while the height of the cushion body 42 remains essentially unchanged. This also applies to the free end in the end region 24, where Figure 7A-A illustrates that the T-shaped cross-section dissolves.Figure 7A-A shows that the longitudinal web 26 in the end region 24 is formed almost exclusively by the cushion body 42.

[0043] Figure 8 shows a second embodiment in which the material forming the cushion body 42 is extended in a groove 64 on the rear end face towards the brush head 10 and forms several lamellae 66 on the back of the brush head 10, which form projections extending from the back and thus a tongue cleaner 68.

[0044] The plastic material forming the cushion body 42 can be a hard component or a soft component. The plastic material forming the cushion body 42 can be identical in its material composition to the plastic material of the base body 40 and differ from the base body only in its color.

[0045] Reference symbol list

[0046] 2 toothbrushes

[0047] 4 brush bodies, 6 cleaning agents

[0048] 8 bristle bundles 10 brush head

[0049] 12 Brush head surface 14 Brush neck 16 Contact area

[0050] 18 Waist 20 Handle 22 T-shaped handle section

[0051] 24 End area 26 Longitudinal web 28 Transverse web 30 Side surface 31 Rear end surface 32 Front end surface

[0052] 34 convex curvature 36 concave curvature

[0053] 40 Base body 42 Cushion body 44 Tapered end surfaces 46 Recess 48 Support surface 50 Circumferential edge

[0054] 52 Side edge of the contact area 54 Lamellas 55 Thumb stop area 56 Convex curved side edge of the handle

[0055] 58 Trough shape 60 Ridge 62 Bend 64 Groove 66 Lamellas 68 Tongue cleaner

[0056] BE Brush head surface plane L Longitudinal plane Q Transverse plane V Front side H Height

Claims

Claims 1. Brush, in particular toothbrush (2), comprising a brush body (4) with a handle (20), a brush head (10) forming a substantially planar brush head surface (12) and a brush neck (14) provided between the handle (20) and the brush head (10), and elongated cleaning agents (6) which project from the brush head surface (12) at a front (V) of the brush body (4), characterized in that the handle (20) has a handle section (22) with a T-shaped cross-section.

2. Brush according to claim 1, characterized in that the T-shaped handle section (22) is oriented such that a transverse web (28) of the T-shaped handle section (22) extends in a transverse plane (Q) which is parallel to a brush head surface plane (BE) containing the brush head surface (12), and a longitudinal web (26) of the T-shaped handle section (22) extending in a longitudinal plane (L) extending perpendicular to it extends centrally from the transverse web (28) to the front (V).

3. Brush according to claim 1 or 2, characterized in that a rear end face (32) is formed by a cushion body (42) made of a soft elastic second plastic which in a cross-sectional view occupies no more than 40% of the area of ​​the T-shaped handle section (22).

4. Brush according to claim 1 or 2, characterized in that a rear end face (31) is formed by a cushion body (42) made of a second, preferably hard plastic and occupies a partial surface of the T-shaped handle section (22).

5. Brush according to claim 3 or 4, characterized in that the T-shaped handle section (22) is formed by the cushion body (42) and a base body (40) connected thereto from a first hard component.

6. Brush according to one of claims 3 to 5, characterized in that the plastic forming the cushion body (42) forms a thumb stop area (55) on the front (32).

7. Brush according to one of claims 3 to 7, characterized in that the plastic forming the cushion body (42) forms a tongue cleaner (68) on the back (32) of the brush head (10).

8. Brush according to one of claims 3 to 7, characterized in that the T-shaped handle section (22) forms flank surfaces (30) extending from a rear end face (31), which are formed partly by the base body (40) and partly by the cushion body (42), and that in a cross-sectional view the base body (40) forms tapered end surfaces (44) which transition smoothly and evenly into the cushion body (42) on the outside and form a recess (46) between them that receives the cushion body (42).

9. Brush according to one of the preceding claims, characterized in that the T-shaped handle section (22) forms convexly curved side edges (56) in a top view of the brush head surface (12).

10. Brush according to one of the preceding claims, characterized in that the crossbar (28) has substantially the same height (H) in a side view over the longitudinal extent of the handle.

11. Brush according to one of the preceding claims, characterized in that the crossbar (28) has a convex cross-sectional shape in a cross-sectional view.

12. Brush according to one of the preceding claims, characterized in that the longitudinal web between its rear end face (31) and the transverse web (28) forms flank surfaces (30) which are oriented obliquely outwards relative to the longitudinal plane (L) at an angle (a) of 1° and 60°, preferably between 1° and 45°, particularly preferably between 5° and 35°.

13. Brush according to one of the preceding claims, characterized in that a bearing area (16) is formed between the handle and the brush neck, which is widened in a top view of the brush head surface (12) compared to the brush neck (14) to form a bearing surface (48).

14. Brush according to one of the preceding claims, characterized in that the handle (20) forms an end region (24) at its end opposite the brush head (10) in which the transverse web (28) and the longitudinal web (26) merge into one another.

15. Brush according to claim 11, characterized in that the brush body (4) is formed in the longitudinal direction of the brush (2) from front to back from the brush head (10), the brush neck (10), the support area (16) and the handle (20).

16. Brush according to claim 42 15, characterized in that the handle (20) is formed from the end region (24) and the T-shaped handle section (22) and that the T-shaped handle section (22) forms at least 70% of the longitudinal extent of the handle (20).

17. Brush according to one of the preceding claims, characterized in that the T-shaped handle section (22) forms at least 30% of the longitudinal extent of the brush body (4).

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