WO2008056072A2

WO2008056072A2 - Removable-blade knife having a handle in the form of two separable parts

Info

Publication number: WO2008056072A2
Application number: PCT/FR2007/052258
Authority: WO
Inventors: Jacques Marsot; Jean-Claude L'huillier; Laurent Claudon; Sébastien Poirel; Arnaud Arduini; Ludovic Mourey
Original assignee: Institut National De Recherche Et De Securite Pour La Prevention Des Accidents Du Travail Et Des Maladies Professionnelles
Priority date: 2006-11-09
Filing date: 2007-10-26
Publication date: 2008-05-15
Also published as: FR2908343B1; FR2908343A1; WO2008056072A3

Abstract

The invention relates to a removable-blade knife having a handle in the form of two separable parts. The knife with a removable blade (1) comprises a handle (2) in the form of two separable parts (17, 23). The handle includes a housing (18) for receiving the blade (1). The housing (18) is defined by two reception areas (18a, 18b) on both sides of a separation surface (22-24) between the two parts (17, 23). Each reception area (18a, 18b) has a width, as viewed when parallel to the separation surface (22-24), that is larger than the depth of said area (18a, 18b) as viewed when perpendicular to said surface (22-24).

Description

Removable blade knife with two separable handles

The invention relates to the field of tools with removable blade and in particular knives, especially for butchering.

Knives with a removable blade are already known in the state of the art.

In this respect reference may be made to patent application DE 17 934 (FRIED) which describes knives or forks, a part of which can be inserted into a handle. The disadvantage of such knives is in the unreliability of fixing the blade in the handle.

US Patent No. 4,011,657 (VANCE) also discloses a knife in which a blade has a curved tongue which penetrates a groove of the handle so as to be immobilized by a pawl system. The reliability of the assembly of the blade in the handle is obtained here by a monoblock handle and a locking mechanism. The disadvantage of this type of knife is that the handle described is likely to retain debris from previous use.

In a food application in general and especially in butchery, it is necessary that the tools such as axes, saws, knives, are fully disinfectable. It is desirable that debris from past use be readily accessible to cleaning and disinfecting tools.

The patent application DE 199 40 484 (BERGER) further describes a knife whose blade has a flat inner portion intended to be fixed in the handle. The handle comprises a main portion comprising a deep housing into which is introduced the inner portion of the blade. An auxiliary portion of the handle is assembled on the main portion to obstruct a small side of the housing and hold the blade in position. Such a knife also has difficulty cleaning, including the housing in which is introduced the inner portion of the blade. The application DE 29 48 987 describes a knife where a blade is fixed between two parts of the handle by means of a screw tightening the two parts. This type of knife requires at least four moving parts relative to each other. Such a knife has in particular the disadvantage that the screw can be lost. If the screw is integral with one of the parts of the handle, gaps between the screw and this part of the handle can be difficult to clean.

In view of the above, the invention aims to overcome the disadvantages of the knives of the state of the art, ensuring inter alia good mechanical cohesion of the tool once assembled.

An object of the invention is to provide a tool with a removable blade, of the type comprising a handle that is more easily cleaned.

The object of the invention is therefore, according to one embodiment, a knife with a removable blade comprising a handle in two separable parts. The handle has a housing for receiving the blade.

The housing is delimited by two reception zones, on either side of a separation surface between the two parts. Each receiving zone has a width, considered parallel to the separation surface, greater than the depth of said zone, considered perpendicular to said surface.

The two parts of the handle have complementary attachment means comprising at least one hook projecting from one of the parts, and a housing adapted to receive said hook. The hook and the housing are curved so as to allow free rotation of one part relative to the other.

In such a knife, the fact that the parts are separable allows that each can be cleaned without being hindered by the present of the other party. In addition, the fact that the receiving areas of the inner part of the blade, corresponding to each part, are wider than deep, allows effective cleaning with a simple tool such as a brush. Thanks to the possible rotational movement between the parts of the handle while the hooking means cooperate, the two parts of the handle can be assembled by a hooking sequence, followed by a rotation until a detent means secures the two parts relative to one another by gripping the blade. This allows the two parts of the handle to be assembled without permanent hinge. The complementary attachment means are easier to clean when they are separated from one another.

Advantageously, the floss of the blade is flat, and parallel to the separation surface between the two parts.

Advantageously, the two parts of the handle comprise complementary latching means, located at a distance from the attachment means and able to immobilize the two parts. The distance between the hooking means and the latching means contributes directly to the mechanical strength of the assembled knife.

Advantageously, one of the parts comprises at least one projecting lug and the other part comprising a mortise adapted to receive the lug. Thanks to the additional guidance between the tenon and the mortise, the assembly of the two parts of the handle can be hyperstatic. This makes it possible to increase the mechanical strength of the assembled knife, especially in the event of shocks.

Advantageously, the post has an oblong shape, complementary to a light formed in the silk of the blade. This improves the retention of the removable blade in the handle.

According to one embodiment, one of the parts is a main part whose receiving zone receives most of the silk. The other part is an auxiliary part that plumps said silk against said receiving zone when the two parts are assembled.

Advantageously, the attachment means comprise at least one hook projecting on the main part, the auxiliary part comprising a housing adapted to receive said hook. The hook and the housing are curved. The curved shape of the hook and the housing allows to leave free a rotational movement between the two parts hung.

Advantageously, the hook passes through a light formed in the silk of the blade. According to a variant, the attachment means comprise two lateral hooks projecting on the main part and located on either side of the blade. This makes it possible to block two rotations and three relative translations between the two parts of the handle. According to another variant, a rear end of the auxiliary part opposite the blade comprises a bead extending transversely with respect to an axis of the knife. The main part comprises an axially deformable rear bead to allow the bead to snap. The rear position of the detent device makes it possible to increase the distance between the snap and the snap. This also allows a mechanical overlap between the bead and the heel more important because when snapping, the main part can deform over the entire distance between the attachment and the rear heel. According to one embodiment, the rear heel has a notch adapted to receive a stud for transversely guiding the rear end of the auxiliary portion relative to the heel.

According to a variant, the main part comprises a centering pin projecting on the main part cooperating with a corresponding hole of the auxiliary part. The pin or the centering pin can block one of the relative rotations between the two handle parts and strengthens the mechanical cohesion of the assembled knife.

According to another embodiment, the centering pin is provided with a circular bead adapted to snap into the corresponding hole.

Other features and advantages of the invention will appear on reading the detailed description of some embodiments taken as non-limiting examples and illustrated by the appended drawings in which: FIG. 1 is a side view of a first embodiment of a knife according to the invention once assembled;

FIG. 2 is a perspective view of the first embodiment of the knife during assembly; FIG. 3 is a detail section along the plane III-III of FIG. 5 of the first embodiment;

FIG 4 is a longitudinal section along the plane IV-IV of Figure 5 of the first embodiment; FIG. 5 is a view from above of the main part of the knife handle according to the first embodiment;

FIG 6 is a cross section along the plane VI-VI of Figure 5 of the first embodiment;

FIG. 7 is a perspective view of a second embodiment;

FIG 8 is a cross section of a third embodiment; and

FIG 9 is a view from above of a fourth embodiment assembled. As illustrated in FIG. 1, the knife is of elongated shape and comprises a blade 1 and a handle 2 in the alignment of the axis 3a of the blade 1. One calls the "front end of the handle 2", the end by where the blade 1 protrudes from the handle 2, the rear end being opposite to the front end. The blade 1 is substantially flat and defines a plane of symmetry (3a, 3b) of the knife. In this way, the knife can be indifferently manipulated by a right-handed or left-handed user. The blade 1 has an outer portion 4 and a floss 5, visible in Figure 2. The handle 2 has a generally flattened shape parallel to the plane of symmetry (3a, 3b). The "upper side of the handle 2" is the lateral side of the handle 2 located on the same side as a non-cutting edge 6 of the outer portion 4 of the blade 1. The "lower side" is the lateral side of the handle 2 located on the side of a cutting edge 7 of the outer portion 4 of the blade 1. The handle 2 comprises successively, from front to rear, a guard 8, a gripping body 9 and a knob 10. The guard 8 and the gripping body 9 have a substantially constant thickness, allowing the knife to rest on a laying surface substantially parallel to the plane of symmetry 3 without the blade 1 in contact with the laying surface. The guard 8 has a greater width than the gripping body 9, protruding radially from the axis 3a of the knife by an upper bulge 11 and by a lower flange 12. The gripping body 10 is also asymmetrical laterally and presents a upper side 13 substantially rectilinear. The opposite lower side has a bulging portion 14. This lateral asymmetry of the handle 2 serves as a visual cue to the user to instinctively grasp the knife, so as to arrange the upper side of the knife in the palm of his hand, the fingers of the The ventric portion 14 is separated from the guard 8 by a concave zone before 15 intended to receive the middle finger of the user. Similarly, the bulging portion 14 is separated from the knob 10 by a rear concave portion 16 for receiving the little finger of the user. When the user exerts a pressing force on the cutting edge 7 towards the front of the knife, the upper bulge 1 1 prevents the hand from slipping on the knife towards the blade 1. The concave front part 15 and the rim 12 are particularly accentuated to prevent the user's finger from sliding towards the cutting edge 7 of the blade 1. The rear concave portion 16 serves to prevent the hand from slipping off the knife when the operator pulls the knife towards the blade. ' back.

Figures 2 to 6 to describe the mechanical constitution of the handle 2. The handle 2 comprises a main portion 17 comprising a housing 18, wherein is introduced the silk 5 of the blade 1. The main portion 17 also comprises a rear heel 19 , an upper front hook 20 and a lower front hook 21. The main part 17 has a main plane 22, parallel to the plane of symmetry 3. The depth of the housing 18 corresponds to the thickness of the silk 5 of the blade 1, so that when the silk 5 is introduced into the housing 18, the silk 5 is in alignment with the main plane 22 or slightly projecting from it. The handle 2 also comprises an auxiliary portion 23 having an auxiliary plane 24 intended to be facing the main plane 22. As illustrated in FIG. 4, the main and auxiliary planes 22 coincide when the handle 2 is assembled, and form a separation surface 22-24 of the two parts 17, 23. The housing 18 is delimited by a reception zone 18a of the main part 17, and a receiving zone 18b of the auxiliary part 23, on either side of the separation surface 22-24. The receiving zone 18a comprises a bottom, and edges which open on the separation surface 22- 24 to allow the silk 5 to be introduced into the housing 18. This receiving zone 18a has a width corresponding to the width of the the silk 5. The depth of the receiving zone 18a corresponds to the thickness of said silk 5. The receiving zone 18b which plates the silk 5 against the zone 18a is, in the illustrated embodiment, a flat surface of width equal to the width of the floss 5. The depth of the receiving zone 18b of the auxiliary portion 23 is zero, therefore less than its width.

The auxiliary part 23 has, at its rear end, a bead 25 intended to cooperate with the rear bead 19, as is described in more detail in FIG. 4. The auxiliary part 23 also has a tenon 26, of oblong shape, in the 3a axis of the knife and projecting from the auxiliary plane 24. The post 26 has an outer surface 27 slightly inclined relative to the perpendicular to the auxiliary plane 24 and intended to cooperate with an opening 28 formed in the silk 5. The tenon 26 has a thickness greater than the thickness of the silk 5. A mortise 30 is formed in the main portion 17, so as to receive the portion of the post 26 protruding from the blade 1. An inner shape 3 1 of the post 26 is intended to cooperate with a corresponding form of the main part 17.

The housing 18 has two lugs 32 corresponding with complementary concave shapes of the silk 5. The lugs 32 serve as axial retention to the blade 1.

The main portion 17 has near the rear heel 19 a recess 33 recessed from the main plane 22. The corresponding portion of the auxiliary portion 23 does not protrude from the auxiliary plane 24, as shown in Figure 1 in the assembled state. The recess 33 opens on the underside of the knob 10 and allows to receive a spacer tool, for example a screwdriver. In this way, the user can force the back gap of the auxiliary portion 23 relative to the main portion 17, deforming the rear heel 19.

As illustrated in Figure 2, the front hooks 20 and 21 project from the main plane 22 and are located at the same axial level, so as to be aligned along a pivot axis perpendicular to the axis of the knife. As can be seen in FIGS. 3 to 5, the front hooks 20 and 21 are curved towards the front of the knife and cooperate with lateral housings 34 formed in the auxiliary part 23.

We will now describe the method of assembly of the knife. In an initial state, the blade 1, the main portion 17 and the auxiliary portion 23 are three parts independent of each other.

In a first step, the floss 5 of the blade 1 is introduced into the housing 18 of the main portion 17 in an axial position determined by the lugs 32. In a second step, the auxiliary portion 23 is brought into a position illustrated in FIG. 2, so that an upper portion 35 of the hooks 20 and 21 coincides with an opening 36 of the lateral housings 34 on the auxiliary plane 24. The shape of the hooks 20 and 21, the lateral housings 34 and the relative position of the end 37 of the auxiliary portion 23 are designed so that the auxiliary portion 23 can pivot substantially around the end 37, while the end of the hooks 20 and 21 penetrates the lateral housings 34. This arrangement forms means for complementary hooking, leaving free a rotational movement between the two parts of the handle 2. Due to the fact that the two hooks 20 and 21 are aligned along a pivot axis, the simultaneous cooperation of the two hooks 20 and 21 in their respective housing brings the main parts 17 and 23 auxiliary facing each other. In a third step of the assembly, the pin 26 enters the slot 28. A functional clearance formed between the housing 18, the pins 32 and the blade 5 of the blade, allows the outer surface 27 of the post to be in adjusted contact. 28. In a fourth step, the bead 25 comes into contact with the end 38 of the bead 19. The bead 25 has a curved shape 39 contacting first with the end 38 of the bead. The angle of the curved portion 39 forces the heel 19 to move backward and allow the bead 25 to enter the end position, illustrated in FIG. 4. In the illustrated example, the pivot axis is substantially perpendicular to the axis of the knife, but any position of the pivot axis makes it possible to bring the bead 25 in register with the heel 19.

We will now, with the help of Figure 7, describe another embodiment which differs from the previous embodiment, in that the attachment means is composed of a single hook 40, located on the axis. 3a of the knife and protruding from the main part 17 through a slot 41 formed with clearance in the silk 5. The main hook 40 cooperates with a corresponding housing 42 in the auxiliary portion 23. Such an embodiment has the advantage of a more robust attachment means. The hook 40 and the housing 42 are fitted to each other in the end position, but have play with respect to each other during the assembly phase. This game allows some rotation around the main hook 40. A centering pin 43 located at a distance from the main hook 40 and cooperating with a hole

44, allows the rear end of the auxiliary portion 23 coincides with the heel 19 when the two parts arrive in the final assembly position. In the illustrated embodiment, the centering pin 43 protrudes from the main portion 17, and the hole 44 is formed in the auxiliary portion 23, but it would be possible to do the opposite.

In the example illustrated in FIG. 7, the indexing pin 43 is provided with a bead 45 able to force fit into the housing 44. In such an embodiment, the precise guidance in the final position between the hook 40, the housing 42 and the deformations of the beads 45 and 25, the assembly of the two parts is of hyperstatic type. This assembly plays on the elasticity of the handle material, which is generally made of plastic, and makes it possible to increase the assembly forces. This gives the knife better impact resistance.

FIG. 8 shows another embodiment, in which the pivoting between the main 17 and auxiliary 23 parts takes place as in the second embodiment around a main hook 40. On the other hand, the alignment of the parts making up the knob 10 is formed by an indexing pin 46 projecting from the auxiliary portion 23 and penetrating into a corresponding housing. In this third embodiment, the indexing pin mainly provides a guidance function and not a hooking function.

Alternatively, illustrated in FIG. 9, the rear portion of the auxiliary portion 23 has an axial stud 48 cooperating with a complementary notch 47 of the heel 19. The stud 48 makes it possible to position the rear portions of the main portion 17 and the auxiliary portion 23, when the hooking means located at the front of the handle 2 is composed of a hook type main hook 40, leaving two free rotations during pivoting.

Another embodiment could result from the combination of the second embodiment described in FIG. 7 with a guide of the silk 5 by a stud 16 projecting from either the auxiliary part 23 or the main part 17.

Other embodiments could be obtained with hooking means located at the rear of the handle 2 and complementary locking means located at the front. The outer shapes of the auxiliary and main portions 23 23 could be asymmetrical and suitably adapted to left-handed or right-handed users.

The invention also relates to blade tools 1 having an outer portion 6 not necessarily flat, such as saws or saws. axes, and whose silk 5 is sufficiently flat so that the receiving areas 18a and 18b of the handle 2 in which is housed the silk 5 are wider than deep.

Claims

1 - Knife with removable blade (1) comprising a handle (2) in two separable parts (17, 23), the handle having a housing (18) for receiving a tang (5) of the blade (1); the housing (18) being delimited by two reception zones (18a, 18b), on either side of a separation surface (22-24) between the two parts (17, 23), each reception zone ( 18a, 18b) having a width, considered parallel to the separation surface (22-24), greater than the depth of said zone (18a, 18b), considered perpendicular to said surface (22-24), characterized by the fact that both parties

(17, 23) of the handle (2) have complementary hooking means (20-21 -34, 40-42) comprising at least one hook (20-21, 40) projecting from one of the parts, and a housing (34, 42) capable of receiving said hook (20-21, 40); the hook (20-21, 40) and the housing (34, 42) being curved so as to leave free rotational movement of one part (23) relative to the other (17).

2 - Knife according to claim 1, in which the tang (5) of the blade (1) is flat, and parallel to the separation surface (22-24) between the two parts.

3 - Knife according to any one of the preceding claims, in which the two parts (17, 23) of the handle (2) comprise complementary latching means (19-25, 43-44), located at a distance from the means of hooking and capable of immobilizing the two parts (17, 23).

4 - Knife according to any one of the preceding claims, in which one of the parts (23) comprises at least one tenon (26) projecting and the other part (17) comprising a mortise (30) capable of receiving the tenon (26).

5 - Knife according to claim 4, in which the tenon (26) has an oblong shape, complementary to a light (28) formed in the tang (5) of the blade (1).

6 - Knife according to any one of the preceding claims, in which one of the parts is a main part (17) whose reception zone (18a) receives most of the silk

(5); the other part (23) being an auxiliary part (23) pressing said silk (5) against the receiving zone (18a) when the two parts (17,

23) are assembled. 7 - Knife according to claim 6, in which the hook (20-

21, 40) projects from the main part (17), the auxiliary part (23) comprising the housing (34, 42).

8 - Knife according to claim 7, in which the hook (40) passes through a slot (41) formed in the tang (5) of the blade (1). 9- Knife according to claim 8, in which the hooking means comprise two lateral hooks (20-21) projecting from the main part (17) and located on either side of the blade (1). 10- Knife according to any one of claims 6 to 9, in which a rear end of the auxiliary part (23) opposite the blade (1) comprises a bead (25) extending transversely relative to an axis (3 a) the knife; the main part (17) comprising a rear heel (19) which is axially deformable to allow the bead (25) to snap into place.

1 1 - Knife according to claim 10, in which the rear heel (19) has a notch (47) capable of receiving a stud (48) to guide the rear end of the auxiliary part (23) transversely relative to the heel ( 19).

12- Knife according to any one of claims 6 to 1 1, in which the main part (17) comprises a centering pin (43) projecting from the main part (17) cooperating with a corresponding hole (44) of the auxiliary part (23).

13- Knife according to claim 12, in which the centering pin (43) is provided with a circular bead (45) capable of snapping into place by force in the corresponding hole (44).