NL2010430C2

NL2010430C2 - Ergonomic knife.

Info

Publication number: NL2010430C2
Application number: NL2010430A
Authority: NL
Inventors: Alexander Hubertus Matilde Cremers
Original assignee: Alexander Hubertus Matilde Cremers
Priority date: 2013-03-12
Filing date: 2013-03-12
Publication date: 2014-09-15
Also published as: WO2014142662A1

Abstract

A knife having a locking mechanism, comprising a handle,a blade holder, connected to the handle via the locking mechanism, for retaining a blade having a cutting edge, wherein the locking mechanism forms a pivoting point between the handle and the blade holder, and wherein the locking mechanism comprises at least two locking positions for locking the handle with respect to the blade holder for using the knife in at least two positions.

Description

Title

Ergonomic knife Field of the invention

The present invention relates in general to a knife having a locking mechanism, comprising a handle and a blade holder for holding a blade.

Description

Known knifes in the art comprise a blade connected to a handle. The blade is covered in the handle in a retracted state, i.e. in a state where the knife is not to be used. In an open state of the knife, the blade is substantially aligned with the blade holder. In such a state the knife is to be used by a person. These knives are known, for example, as pocket knives.

In a further example, the pockets knives may comprise a locking mechanism arranged for locking the blade holder in a position relative to the handle, typically an open state of the knife, to prevent accidently movement of the blade during use.

A drawback of the known knives is that during long-term or repeated use of these knifes, complaints related to pain in the joints of a wrist, i.e. arthralgia, complaints related to loss of power in hands and/or infections to the hands or wrists, among others, are common.

Another drawback of these knives is that the operability of the knives, i.e. the different uses for which these knives can be used, is limited as in practice, different types of knives, having different types of orientation of the blade holder to the handle are used for different types of applications.

Accordingly, it is an object of the present invention to propose a knife having a locking mechanism to overcome the drawbacks set out above, i.e. to provide for an ergonomic knife which relieves the wrist during use, especially during long-term and repeated use of the knife.

Another object of the present invention is to provide for a single knife which is able to be used for different types of applications, i.e. different types of uses.

In order to accomplish that object, the present invention, according to a first aspect thereof, provides for a knife having a locking mechanism, comprising a handle, a blade holder connected to the handle via the locking mechanism, for retaining a blade having a cutting edge, wherein the locking mechanism comprises at least two locking positions for locking the handle with respect to the blade holder for using the knife in at least two positions.

The invention is based on the insight of the inventor that in order to use a knife for different applications, i.e. different uses, a wrist of a user can be relieved by integrating a locking mechanism for locking an angle between the blade holder and the handle, which provides the possibility for a user to use the knife in at least two different positions.

The locking mechanism according to the present invention is understood as a mechanism which is able to block any pivoting movement of the handle with respect to the blade holder, when in a locked position. In a freed position, the handle is able to pivot around the pivoting point with respect to the blade holder. In another example, it is the blade holder which is arranged to pivot around the pivoting point with respect to the handle.

In an embodiment, the pivoting point is understood as an hinge point.

As, according to the invention, the knife can be used in at least two different positions, an ergonomic effect is obtained as the inventor noted that in order to use the knife efficiently, i.e. cut efficiently, a cutting edge of the blade should be substantially aligned with the object to be cut. Having a knife with at least two different positions, a user operating the knife can choose, and/or vary, the angle of the handle with respect to the blade holder.

The knife according to the present invention is especially suitable for providing different types of grips, and at the same time, for example, maintaining the alignment of the cutting edge of the blade with respect to the object to be cut.

For example, in a forward knife grip technique of the handle, when grasped by a user, the blade opposes the little finger. The forward knife grip technique is known in the art as the traditional grip technique for holding a knife. Such a grip technique can be obtained with the knife according to the present invention, whenever the locking mechanism is in a first locking position such that the handle with respect to the blade holder is substantially aligned.

In another example, in a reverse knife grip technique of the handle, when grasped by a user, the blade opposes the thumb. Such a grip technique can be obtained with the knife according to the present invention, whenever the locking mechanism is in a second locking position such that an angle of the handle with respect to a cutting side of the blade holder is a reflex angle.

Using a knife in such a position is advantageous, especially for, for example, cutting a carpet, cutting roof materials, paper, plasterboard, etc.

In another example of the present invention, the locking mechanism comprises one of a push lock, frame lock, liner lock, lock back, picklock, axis lock and ball bearing lock.

With a liner lock, for example, the blade holder is held in a locked position by a leaf spring that butts up against the tang of the blade holder, preventing the blade holder from moving to a closed position. To release the lock, a user must press a lock bar back towards the handle side, such that the blade holder is allowed to move to a closed position.

In another example, the locking mechanism comprises an axis lock, comprising an axis and two elements rotatable over the axis, wherein the elements are connected to the blade holder and the handle, respectively. The two elements further comprise interworking mating means, for locking a relative position of the elements to each other. Such interworking mating means comprise, for example, a protrusion and a recess. The locking mechanism is in a locking position when the recess of an element is in the protrusion of the other element.

In another embodiment of the present invention, the locking mechanism comprises a first locking position such that the handle with respect to the blade holder is substantially aligned, and a second locking position such that an angle of the handle with respect to a cutting side of the blade holder is a reflex angle.

For example, the angular displacement of the handle with respect to the blade holder is between 260° and 300°, preferably between 275° and 290°, and even more preferably around 280°. In such a case, the knife according to the present invention is suitable for use in the first locking position with a forward knife grip technique, and in the second locking position with a reverse knife grip technique, wherein the alignment of the blade with respect to the cutting object is the same.

In yet another embodiment of the present invention, the locking mechanism comprises further locking positions such that an angular displacement of the handle with respect to the blade holder is between a corresponding angular displacement of the handle with respect to the blade holder in the first locking position and a corresponding angular displacement of the handle with respect to the blade holder in the second position.

The advantage of the above described embodiment is that each user operating the knife is able to set an angle between the handle with respect to the blade holder such that the user can himself determine which angle is most convenient for him to operate the knife.

In an even further embodiment of the present invention, the blade holder further comprises a cover for covering the blade. Here, even when the knife holder is in an open state, the blade is protected from the outside using the cover. In such a case, the presence of hazardous situations is prevented.

In an embodiment of the present invention, the handle further comprises a rotational mechanism arranged for rotating and locking the handle over a longitudinal axis of the handle with respect to the locking mechanism.

It was the insight of the inventor, that when the knife according to the present invention is used with as well a forward knife grip technique as well as a reverse grip technique, the ergonomic aspects of the knife are improved whenever the handle is able to be rotatable adjustable over a longitudinal axis of the handle.

For example, in a first locking position in which the handle is substantially aligned with the blade holder, the knife is used, using a forward knife grip technique. In the second locking position, in which the angle between the handle with respect to a cutting side of the blade holder is a reflex angle, the knife is used, using a reverse knife grip technique. The inventors noted that in such a case, the handle of the knife should be rotated and fixed along its longitudinal axis to maintain its ergonomic capabilities with the reverse knife grip technique.

In an example, the rotational mechanism comprises a pull bolt, a compression spring and a rotary knob for setting a longitudinal rotation of the handle. To rotate the handle, the handle is first freed from the locking mechanism by rotating the rotary knob counter clockwise. In such a freed position, the handle is able to rotate over its longitudinal axis, i.e. over the pull bolt. Once the handle has rotated to a desired rotation, the handle can be rotatable fixed to the locking mechanism by clockwise rotating the rotary knob.

In an even further example of the present invention, the blade holder is connected to the locking mechanism via a cutout provided at an opposite side of the blade holder compared to a cutting side of the blade such that a person operating the knife is able to place a portion of the person’s hand between the pivoting point and the blade.

It was the insight of the inventor that the knife according to the present invention, when used with a reverse grip technique, for example when the locking mechanism is in the second locking position, can be operated more accurately, for example when cutting a carpet, when a cutout is provided at an opposite side of the blade holder compared to a cutting side of the blade, i.e. between the pivoting point and the blade.

A user placing a portion of its hand in the cutout, will experience more stability of the knife during cutting, and can thus more reliably control the knife in the reverse grip technique. In an example, the cutout is provided such that the person operating the knife is able to place the portion of the person’s hand between the pivoting point and the cutting edge of the blade

The invention will now be explained in more detail with reference to the appended figures, which merely serve by way of illustration of the invention and which must not be construed as being limitative thereto.

Brief Description of the Drawings

Figure 1 shows, in a schematic form, an example of an embodiment of a knife having a locking mechanism according to the present invention.

Figure 2 shows, in a schematic form, an example of an embodiment of a knife having a locking mechanism, comprising a rotational mechanism arranged for rotating and locking the handle over a longitudinal axis of the handle with respect to the locking mechanism, according to the present invention.

Figure 3a-3d show, in a schematic form, examples of an embodiment of a knife having a locking mechanism and comprising the rotational mechanism, wherein the transitions of knife from a first position to a second position is shown.

Detailed description of the drawings

Figure 1 shows, in a schematic form, an example of an embodiment of a knife 1 having a locking mechanism 6 according to the present invention.

In the example of figure 1, the knife 1 comprises a handle 2 which is used for holding the knife 1 by a user. The knife 1 further comprises a blade holder 5 for holding a blade 4 having a cutting edge 9. In the present example, the blade 4 is placed in the blade holder 5, however, a blade holder 5 suitable for, but without having actually a blade 4 present falls within the scope of the appended claims.

The knife 1 further comprises a locking mechanism 6 forming a pivoting point between the handle 2 and the blade holder 5, wherein the locking mechanism 6 comprises at least two locking positions for locking the handle 2 with respect to the blade holder 5 for using the knife in two positions 10, 11.

As is clearly seen from figure 1, the knife 1 can be used in two different positions 10, 11, i.e. a first position 10 in which the locking mechanism 6 is in a first locking position 12, and in a second position 11 in which the locking mechanism 6 is in a second locking position 13. In the first position 10, the handle 2 is substantially aligned with the blade holder 5, such that the knife 1 can be used as a traditional pocket knife. In the second position 11, the knife 1 is to be used for, for example, cutting a carpet.

In the second position 11, the handle 2 of the knife 1 is locked in a position about perpendicular to the blade holder 5, in opposite direction of the cutting edge 9 of the blade 4. The angle the handle 6 makes with the blade holder 5 is then defined as a reflex angle, i.e. an angle larger than 180° and smaller than 360°.

Using the knife 1 in the first position 10, a person operating the knife usually holds the handle 2 in a forward knife grip technique, such that the index finger of the person is closest to the locking mechanism 6.

The knife in the second position 11, a person operating the knife 1 usually holds the handle 2 in a reverse knife grip technique, such that the little finger, i.e. pink, of the person is closest to the locking mechanism 6.

The blade holder 5 is further connected to the locking mechanism 6 via a cutout 8 provided at an opposite side of the blade holder 5 compared to a cutting side 9 of the blade 4 such that a person operating the knife 1 is able to place a portion of the person’s hand between the pivoting point and the blade 4.

The cutout 8 is especially suitable when the knife 1 is in the second position 11, because then, when a user holds the handle 2 in a reverse knife grip technique, the little finger of the user can be placed in the cutout 8. This provides additional stability and control over the knife 1.

For safety reasons, the knife 1 also comprises a cover 3 for covering the blade 4.

According to the present invention, the locking mechanism 6 can be implemented in several ways.

In an example, a ball and socket joint arranged to rotate in an organ. By clamming the organ around the ball and socket joint, the handle can be locked.

Figure 2 shows, in a schematic form, an example of an embodiment of a knife 21 having a locking mechanism 32, having a pivoting point 31, comprising a rotational mechanism 26, 27, 28 arranged for rotating and locking the handle 29 over a longitudinal axis 33 of the handle 29 with respect to the locking mechanism 32, according to the present invention.

In this example, the blade holder 25, the cutout 23, the blade 24, the cutting side 30 and the cover 22 all have same function as the blade holder 5, the cutout 8, the blade 4, the cutting side 9 and the cover 3 of the knife 1 shown in figure 1, respectively.

The rotational mechanism 26, 27, 28 comprise a pull bolt 26, a compression spring 27 and a rotary knob 28 for setting a longitudinal rotation 33 of the handle 29.

Here, the rotary knob 28 is turned counter-clockwise to release the handle 29 from a force, i.e. the tension, of the compression spring 27, which fixates the handle 29 to the locking mechanism 32. After the handle 29 is freed, it is able to rotate freely around its longitudinal axis 33. Once the handle 29 is rotated, for example 180°, the handle 29 is fixed again to the locking mechanism 32 by turning the rotary knob 28 clockwise.

Figure 3a-3d show, in a schematic form, examples of an embodiment of a knife 41, 51, 61, 71 having a locking mechanism and comprising the rotational mechanism, wherein the transitions of knife from a first position 41 to a second position 71 is shown.

Here, it is shown that besides the two positions in which the knife can be used, the handle 42 of the knife 41, 51, 61, 71 is also rotated and fixed 180° over its longitudinal axis in the second position 71, compared to the knife in the first position 41.

The present invention has been explained in the foregoing by means of a number of examples. As those skilled in the art will appreciate, several modifications and additions can be realized without departing from the scope of the invention as defined in the appended claims.

Claims

A knife with a blocking mechanism, comprising a handle; a blade holder, connected to the handle via the blocking mechanism, for holding a blade with a cutting side, wherein the blocking mechanism forms a pivot point between the handle and the blade holder, and wherein the blocking mechanism comprises at least two blocking positions for blocking the handle at relative to the blade holder for using the knife in at least two positions.

A knife according to claim 1, wherein the blocking mechanism comprises at least one of a frame lock ("frame lock"), liner lock ("liner lock"), lockback, picklock, axis lock ("axis lock"), and ball bearing lock ("ball bearing lock") ").

3. Knife as claimed in any of the foregoing claims, wherein the blocking mechanism comprises a first blocking position such that the handle is substantially aligned with respect to the blade holder, and a second blocking position such that an angle of the handle with respect to a cutting side of the blade holder is a reflex angle.

The knife of claim 3, wherein, in the second blocking position, the angular rotation of the handle relative to the blade holder is between 260 ° and 300 °, preferably between 275 ° and 290 °, and more preferably about 280 °.

The blade of any one of claims 3 or 4, wherein the blocking mechanism comprises further blocking positions such that an angular rotation of the handle relative to the blade holder between a corresponding angular rotation of the handle relative to the blade holder in the first blocking position and a corresponding angular rotation of the handle relative to the blade holder is in the second blocking position.

6. Knife as claimed in any of the foregoing claims, wherein the blade holder further comprises a cover cap for covering the blade.

The blade of any one of the preceding claims, wherein the handle further comprises a rotation mechanism adapted to rotate the handle about a longitudinal axis of the handle with respect to the locking mechanism.

The knife of claim 7, wherein the rotation mechanism further comprises a draw bolt, a compression spring and a rotary knob for adjusting a longitudinal rotation of the handle.

The blade of any one of the preceding claims, wherein the blade holder is connected to the locking mechanism through a notch provided on an opposite side of the blade holder compared to a cutting side of the blade such that a person operating the blade is able to part of the person's hand between the pivot point and the blade.

The knife of claim 9, wherein the notch is provided such that the person operating the knife is able to place a portion of the person's hand between the pivot point and the cutting side of the blade.