DE9115517U1 - Handle for hand tools, especially for professional knives - Google Patents

Description

Patent Attorney Mülbergerstr. 65 * -"Z 'Authorized Representative, at Dipl.-Ing. Volkhard Kratzsch D-7300 Esslingen " European Patent Office PO Box 90 European Patent Attorney Telephone 0711/317000 Deutsche Bank Esslingen 210906 Fax 0711/313248 Postgiroamt Stuttgart 10004-701

Friedr. Dick GmbH

9 December 1991

7300 Esslingen

Attorney file 5177

Handle for hand tools, especially for professional knives

The invention relates to a handle for hand tools, in particular for professional knives, e.g. for butchers, cooks or the like, of the type mentioned in the preamble of claim 1.

In known handles of this type, the central plane of the handle body, which is roughly symmetrical to the wide surfaces of the handle, runs over the entire length of the handle body in alignment and extension, for example, with the plane of a knife blade. It has been shown that professional knives equipped with such a handle, even if the narrow and/or wide surfaces of the handle body are convexly curved outwards and the handle body has a significant cross-sectional volume, tend more or less to slip out of the hand when handled in one way or another, e.g. when used as a butcher's knife, which is used relatively frequently in the commercial sector. There is also a tendency for the professional knife to be rotated in the hand around the longitudinal axis of the handle when handled, despite a firm grip. The knife handle must therefore be grasped and gripped very tightly in order to prevent it from slipping out and also from rotating around the longitudinal axis of the handle to some extent. Especially when

If moments around the longitudinal axis are to be transmitted during use, the handle must be gripped and held particularly tightly. Even then, slipping or turning is unavoidable. It has also been shown that greater forces for gripping and clasping the handle are detrimental to sensitive handling and control of the professional knife. In addition, if the knife is gripped tightly, painful pressure points and cuts can occur in the hand gripping the handle, with ^associated rapid weakening or fatigue.

The invention is based on the object of creating a handle of the type mentioned at the outset according to the preamble of claim 1, which enables an even better power transmission from the surrounding

¹ ^ grasping hand over the handle body onto the hand tool, in particular a knife blade, with reduced expenditure of force, whereby in particular a good level of security is achieved against rotation of the handle body in the grasping hand about the longitudinal axis of the handle and also against slipping in the longitudinal direction.

The object is achieved according to the invention in a handle of the type mentioned in the preamble of claim 1 by the features in the characterizing part of claim 1. Further independent features of the invention arise from claims 2 to 4. Further advantageous features of the invention and embodiments are contained in claims 5 to 20.

Because the handle body has a significant cross-sectional volume and is twisted clockwise or counterclockwise at least along part of its length around the handle's longitudinal axis, depending on whether the handle is designed as a right-handed or left-handed grip, the handle body follows the natural course of a hand grasping it, without any forced postures being necessary when grasping it. The handle body nestles in the natural shape of the grasping hand

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so that the handle body fits almost perfectly in the hand. As a result, very large forces can be transferred from the hand via the handle body to a hand tool, e.g. the blade of a professional knife, with little effort. The handle body fits very securely in the hand.

against slipping in the longitudinal direction in the hand. Due to the twisted shape of the handle body, surfaces of the handle body counteract any slipping in the longitudinal direction by providing positive locking and acting as resistance. Furthermore, even greater security against

¹ ^ Slipping of the handle body around the handle body's longitudinal axis in the hand enclosing the handle body is achieved. At the same time, a tool equipped with this handle, especially a professional knife, can be guided more reliably and safely and at the same time more sensitively. The

¹ ^ Reduced effort. With only a small amount of effort, it is possible to transfer large forces via the handle to a hand tool, in particular the blade of a professional knife, and to the material being cut. The handle body can be designed with a pronounced rectangular outer contour or with a pronounced rectangular cross-section, without the longitudinal edges otherwise present with such a cross-section in the transition area between the narrow and wide surfaces cutting painfully into the hand grasping the handle body. In this way, the moment that can be developed around the longitudinal axis of the handle by the hand grasping the handle body can be increased even further without the need for greater grasping force. If, for example, a professional knife is equipped with a handle according to the invention, the knife blade runs essentially in the direction of the extension of the handling arm in almost all handling of the professional knife and is therefore in a natural alignment.

Further details and advantages of the invention will become apparent from the following description.
35

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The full wording of the claims is not reproduced above solely to avoid unnecessary repetition, but instead reference is made to them merely by naming the claim numbers, whereby all of these claim features are to be regarded as expressly disclosed at this point and essential to the invention. All features mentioned in the above and following description as well as the features that can be inferred solely from the drawing are further components of the invention, even if they are not particularly highlighted and in particular are not mentioned in the claims.

The invention is explained in more detail below using an embodiment shown in the drawing.

¹ ^ Fig. 1 a schematic side view of a handle

for hand tools, in particular for professional knives, with a part of a blade,

Fig. 2 is a schematic plan view of the handle in the direction of arrow II in Fig. 1,

Fig.3

and 4 each show a visual front view and rear view of the handle in arrow direction III and IV in Fig. 1,

Fig. 5 is a schematic section along the line V-V in Fig. 2 .

The drawing shows a schematic representation of a handle 10 for hand tools, which is designed in particular for professional knives, e.g. knives for butchers, cooks or the like. In the embodiment shown, such a professional knife is shown schematically, in particular for butchers. The handle is formed from a handle body 11, which extends in the direction of the handle's longitudinal axis 13. A blade 12 is attached to the handle body 11. The handle body 11 consists, for example, of

made of a physiologically harmless plastic material and can have a non-slip, non-slip surface. The handle body can consist of a one-piece injection-molded part and thus of solid material. The handle of the blade 12, not visible here ^, can be molded around by the material of the handle body 11.

In another embodiment, not shown, the handle body 11 advantageously consists of at least two handle shells from which it is composed. In this case too, plastic can be used as the material. Instead, however, a durable precious wood or another suitable material is also possible.

The handle body 11 is molded onto the hand tool, e.g. onto the blade 12 shown, or instead is secured in some other way with force and/or form. In another embodiment, not shown, the handle body 11 is secured to another hand tool, e.g. a file or the like, instead of to the blade 12 shown.

The handle body 11 has a substantial cross-sectional volume and is twisted at least over part of its longitudinal extent around the schematically indicated handle longitudinal axis 13 in an anti-clockwise direction, as shown in the drawings, or instead in a clockwise direction by the angle o£. In particular, the previously described handle body 11 is twisted with its rear end 14 relative to its front end 15 around the handle longitudinal axis 13 in an anti-clockwise direction, as shown, or instead in a clockwise direction by the angle oC.

As can be seen in particular from Fig. 3 to 5, the handle body 11, which has a significant cross-sectional volume, has an at least essentially rectangular outer contour, the two narrow surfaces 16 and 17

above and below and whose two broad surfaces 18 and 19 run on both sides. The rear end 14 is rotated in relation to the front end 15 around the handle longitudinal axis 13 in an anti-clockwise direction, as shown, or instead in a clockwise direction by the angle oC. When above and below ° a torsion by the angle oC in an anti-clockwise direction around the handle longitudinal axis 13 is mentioned, this direction of rotation is based on a view in the direction of arrow IV in Fig. 1, i.e. a view of the rear end 14 in the handle longitudinal direction. It is understood that

¹ ^ that when viewed in the opposite direction in the direction of arrow III in Fig. 1, the handle body 11 is twisted about the longitudinal axis 13 in a clockwise direction by the angle ^ ₇ C. In this view, alternatively, in an embodiment not shown, the handle body 11 can be twisted in the opposite direction in a corresponding anti-clockwise direction.

As the section in Fig. 5 in particular shows, the handle body 11 has an at least essentially rectangular cross-section. In view of the fact that the handle body 11 represents an essentially linear part, the shape of the handle body 11 thus results in approximately the shape of a linear rectangular torsion bar, as is familiar, for example, from calculation examples in mechanics.

The ratio of the width of the wide surfaces 18,19 to the width of the narrow surfaces 16,17 of the handle body 11 is approximately 2 to 1. Each wide surface 18,19 has a width of approximately between 25 mm and 35 mm. Preferably the width of each wide surface 18,19 is approximately between 27 mm and 31 mm. Each narrow surface 16,17 has a width of approximately between 10 mm and 20 mm. Preferably the width of each narrow surface 16,17 is approximately between 14 mm and 16 mm.

The schematically drawn central plane 20, which is approximately symmetrical to the broad surfaces 18, 19, runs in the area of the front end 15 of the handle body 11 approximately in extension of the plane within which the blade 12 of a 5

knife or another hand tool not shown. In the area of this front end 15, the central plane 20 and the plane of the blade 12 coincide.

On the other hand, the same central plane 20, which runs approximately symmetrically to the wide surfaces 18,19, runs in the area of the rear end 14 of the handle body 11 at an angle OC, thus at the mentioned torsion angle, with respect to the plane within which the blade 12

extends.
15

The torsion angle oC is approximately in the order of magnitude between 10° and 40°, whereby it can preferably be, for example, approximately 30°.

^ The longitudinal edges in the transition area of the narrow surfaces 16,17 into the wide surfaces 18,19 are slightly rounded. The wide outer surfaces 18,19 are at least slightly curved outwards. In the same way, the two narrow surfaces 16 and 17 are also at least slightly curved outwards.

² ^ curved. The convex curvature of the wide surfaces 18,19 and the narrow surfaces 16,17 is selected so that the pronounced rectangular outer contour and the pronounced rectangular cross section of the large-volume handle body 11 are essentially retained.

The handle body 11 has in the area of its front end a projection 21 which protrudes at least downwards beyond the lower narrow surface, e.g. in side view it is approximately hook-shaped, which serves as a finger guard or the like.

In the illustrated embodiment of the handle 10, its handle body 11 is twisted counterclockwise by the angle *c about the handle longitudinal axis 13 when viewed in the direction of arrow IV in Fig. 1 and is designed as a right-handed handle in this configuration.

In the left-handed grip design, which is not shown, the grip body 11 is instead twisted clockwise by the torsion angle <<.

The essentially rectangular outer contour and the essentially rectangular cross-section of the handle body 11 ensure that the handle 11 can be easily gripped by hand.

, r- can be included, whereby a good frictional connection can be achieved &igr;&ogr;

without the rounded longitudinal edges between the narrow surfaces 16,17 and the wide surfaces 18,19 cutting painfully into the hand grasping the handle 10. The torsion of the handle body 11 through the angle <£. makes a very decisive contribution to this.

If, for example, a professional knife equipped with the described handle 10, e.g. a butcher's knife, is handled in a cutting position in which the handle body 11 is separated from the

right hand in such a way that the fingers are essentially-25

lent on the left broad surface 18 in Fig. 4 and 5 and the right broad surface 19 is located approximately in the area of the palm, the handle 10 and thus the entire professional knife is reliably grasped and held and guided safely. The handle body 11 follows the wide surfaces 18,19 and due to the described torsion the natural grip position of the right hand holding the handle body 11. This enables sensitive, slip-proof and above all twist-proof guidance

and handling of the professional knife. Above all, 35

with only little effort the transmission of large

Forces can be transferred via the handle 10 to the blade 12 and to the material being cut. The force required for holding and using the professional knife is transferred from the human hand to the handle and to the blade 12 in an ergonomically favorable manner due to the described design of the handle body 11. When grasping the handle body 11, large moments around the longitudinal axis 13 of the handle can be transferred with little or no fatigue. Thus, with relatively little effort, practically the full force can be transferred to the blade via the handle 10, and this is the case for all possible handling of the professional knife, in particular, for example, when cutting, even when moments have to be transferred in the direction around the longitudinal axis 13 of the handle. When handling the professional knife in the

In the cutting position described, the handle 10 fits snugly and tightly into the natural hand position, whereby the blade 12 is then practically aligned as an extension of the arm and in this way the transfer of large forces from the arm and the hand

via the handle 10 onto the blade 12 and the material being cut. The same or comparable advantages also arise when the professional knife is held in the fist grip by the user's right hand, for example. The thumb of the right hand is supported in the area of the left wide surface 18 in Fig. 4 and 5, while the index finger is supported and placed on the other wide outer surface 19. The knife can therefore be reliably grasped and safely held and guided even in the fist grip, ^Q whereby the transmission of large forces is possible with only a small amount of force.

The handle 10 also offers great advantages when the professional knife equipped with it is handled in the so-called boning position, as is used by butchers. This is the essentially

reversed fist grip position, in which the fingers essentially grip the upper narrow surface 16 and the grip body 11 is supported approximately in the area of the lower narrow surface in the palm area. Even then, the hand finds a good, coherent position and support on the grip body 11. In all of this, the rotation around the torsion angle cC ensures that the grip body 11 essentially fits snugly and positively into the natural grip of the right hand in every grip position.

¹ ^, so that a sensitive, non-slip guidance of the professional knife and the transmission of large forces is achieved with little or no fatigue, whereby the handle body 11 lies extraordinarily well and securely, in particular twist-proof, in the hand without

!5 painful pressure points result.

Claims (20)

Expectations 1. Handle for hand tools, in particular for professional knives, e.g. for butchers, cooks, or the like, with a handle body (11) extending in the direction of the handle longitudinal axis (13), characterized in that the handle body (11) has a substantial cross-sectional volume and is twisted clockwise or counterclockwise around the handle longitudinal axis (13) at least over part of its longitudinal extension. 2. Handle for hand tools, in particular for professional knives, e.g. for butchers, cooks or the like, with a handle body (11) extending in the direction of the handle longitudinal axis (13), characterized in that the handle body (11) has a significant cross-sectional volume and is twisted with its rear end (14) relative to its front end (15) around the handle longitudinal axis (13) in a clockwise or anti-clockwise direction. 3. Handle for hand tools, in particular for professional knives, e.g. for butchers, cooks or the like, with a handle body (11) extending in the direction of the handle longitudinal axis (13), characterized in that that the handle body (11) has a substantial cross-sectional volume and an at least substantially rectangular outer contour, the narrow surfaces (16, 17) of which and below and their broad surfaces (18,19) on both sides &ngr; e r 5 run, and that the rear end (14) is twisted clockwise or counterclockwise around the handle longitudinal axis (13) in relation to the front end (15) of the handle body (11). 4. Handle for hand tools, in particular for professional knives, e.g. for butchers, cooks or the like, with a handle body (11) extending in the direction of the handle longitudinal axis (13), characterized in that that the handle body (11) has a substantial ^cross -sectional volume and an at least substantially rectangular cross-section, the narrow surfaces (16, 17) of which run at the top and bottom and the wide surfaces (18, 19) of which run on both sides, and that the rear end (14) is twisted clockwise or anti-clockwise around the handle longitudinal axis (13) with respect to the front end (15) of the handle body (11). 5. Handle according to one of claims 1 to 4, characterized in that the torsion angle [*£) is approximately in the order of magnitude between 10° and 40°, in particular approximately in the order of magnitude of 30°. 6. Handle according to one of claims 1 to 5, characterized in that the handle body (11) has approximately the shape of a linear and approximately rectangular torsion bar. 7. Handle according to one of claims 1 to 6, characterized in that the ratio of the width of the wide surfaces (18, 19) to the width of the narrow surfaces (16, 17) of the handle body (11) is approximately 2 to 1. 8. Handle according to one of claims 1 to 7, characterized in that each broad surface (18, 19) has a width of approximately between 25 mm and 35 mm, preferably approximately 27 mm to 31 mm. 9. Handle according to one of claims 1 to 8, characterized in that each narrow surface (16, 17) has a width of approximately between 10 mm and 20 mm, preferably approximately from 14 mm to 16 mm. 10.Handle according to one of claims 1 to 9, ² ^ characterized in that the central plane (20) which is approximately symmetrical to the broad surfaces (18,19) in the region of the front end (15) of the handle body (11) runs approximately in extension of a plane within which a hand tool, eg ² ^ the blade (12) of a knife, extends. 11.Handle according to one of claims 1 to 10, characterized in that the central plane approximately symmetrical to the broad surfaces (18, 19) (20) in the region of the rear end (14) of the handle body (11) at an angle (<jC) approximately in the order of magnitude between 10° and 40°, e.g. approximately 30°, with respect to a plane within which a hand tool, e.g. the blade (12) of a knife, extends. 12. Handle according to one of claims 1 to 11, characterized in that the longitudinal edges in the transition area of the narrow surfaces (16,17) into the wide surfaces (18,19) are slightly bevelled. are rounded. 13. Handle according to one of claims 1 to 12, characterized in that the wide surfaces (18, 19) and/or the narrow surfaces (16, 17) are at least slightly curved outwards. 14. Handle according to one of claims 1 to 13, characterized in that the handle body (11), viewed in the direction of its rear end (14), is twisted counterclockwise about the handle longitudinal axis (13) and is designed as a right-handed handle. 15. Handle according to one of claims 1 to 13, characterized in that the handle body (11), viewed in the direction of its rear end (14), is twisted clockwise about the handle longitudinal axis (13) and is designed as a left-handed handle. 16. Handle according to one of claims 1 to 15, characterized in that the handle body (11) has, at least in the region of the front end, a projection (21), e.g. approximately hook-shaped, protrusion, which protrudes at least downwards beyond the lower narrow surface (17) as a finger guard or the like. 17. Handle according to one of claims 1 to 16, characterized in that the handle body (11) consists of plastic. 18· Handle according to one of claims 1 to 17, characterized in that the handle body (11) consists of a one-piece injection-molded part. 19. Handle according to one of claims 1 to 17, characterized in that the handle body (11) consists of at least two handle shells composed. 10 20. Handle according to one of claims 1 to 19, characterized in that the handle body (11) is molded onto the hand tool, e.g. a knife, a file or the like, or is otherwise fastened in a force-fitting and/or form-fitting manner.