EP0442004B1 - Knife with interchangeable blades - Google Patents

Abstract

The invention relates to a knife with interchangeable blades (M), having a housing (1) and a slide (4) which is guided longitudinally displaceably in the housing (1) and can be fixed at predetermined spacings of a catch (6) formed on the housing (1), and on which the blade (M) is interchangeably held by means of a pin (18, 19) engaging into a hole of the blade (M). To be able to use such a knife with different commercially available blades (M), the particular blade (M) is held on the slide (4) by means of an interchangeable holder (17a, 17b) or a turning holder (17c) which is mounted on the slide (4) so as to be rotatable through 180 DEG and is provided at each end with a pin (18, 19), the diameters of which are made in various sizes in accordance with the different commercially available blades (M).

Description

The invention relates to a knife for interchangeable knife blades with a housing and a longitudinally displaceable slide in the housing, which can be fixed at predetermined intervals of a detent formed on the housing and on which the knife blade is held interchangeably by means of a pin engaging in a hole in the knife blade, the respective knife blade is held on the slide by means of a holder which is provided with a pin corresponding to the hole of the respective knife blade and is interchangeably mounted on the slide.

Knives of this type are known in various designs. They are used as so-called technical knives in various craft work, for example when laying carpets. In addition to trapezoidal carpet knife blades that are designed with either a smooth or hook-shaped cutting edge, so-called snap-off blades are also used. Knife blades of this type are divided into several sections by predetermined breaking lines; as soon as the cutting edge of the respective front section has become blunt, the front section is broken off, so that a new section of the snap-off blade with a sharp cutting edge is then available for the work ahead.

The known knife blades are not only designed differently with regard to their respective purpose, but also are also held in different ways on the slider which is longitudinally displaceable in the knife housing. In addition to slot-like notches in the back of the knife blade, many of the known knife blades are provided with a hole which can be placed on a pin of the respective slide for holding the knife blade. However, the knife blades most commonly used in practice differ not only in their thickness and width and length, but also in the position and diameter of the hole provided for mounting the knife blade on the slide. For this reason, despite a certain standardization, it is necessary to use different knife housings for different knife blades.

From DE-A 29 02 642 a knife of the type described is known, in which the holder can be fixed in different positions on the slide and is provided with two concentrically formed pins of different diameters, which cooperate with the differently sized holes of the different knife blades. In order to adapt the holder to different knife blades, the holder must be removed and adjusted relative to the slide. In addition, a locking unit acted upon by spring force is required, which holds the holder in the respective position on the slide.

The invention has for its object the known knife, which can be used universally for most of the commercially available blades despite the differences of such knife blades in terms of length, width, thickness and hole formation, such that there is a simplified adaptation to the blade to be used in each case .

The solution to this problem by the invention is characterized in that the holder is designed as a reversible holder which is rotatably mounted on the slide by 180 ° and is provided at each end with a pin, the diameter of which is of different sizes in accordance with the various commercially available knife blades.

This inventive development of a reversible holder mounted on the slide for holding the exchangeable knife blades has the advantage that the same knife housing can be used for different commercially available knife blades, for example for carpet knife blades and snap-off blades, whose width is between 18 and 19 mm and their thickness is between 0.5 and 0.65 mm and which, apart from a different length, have holes of either 5.2 or 7.1 mm in order to be fixed on the slide of the knife. Despite these sometimes considerable differences with regard to the design of the usable knife blades, the respective knife blade is reliably fixed both on the slide and in the guide channel of the knife housing, because the turning holder can be rotated through 180 °, whereby not only one for the correct determination of the knife blade to be used in each case Pin with the correct diameter is available, but also the distance of the knife back to the knife guide channel formed in the knife housing is set such that the back of the respective knife blade lies reliably against the guide channel. The invention thus creates a universal technical knife for using differently designed knife blades.

To ensure that the holder or turning holder is reliably guided in the blade channel of the housing and against rotation In order to achieve a secure fixing of the respective knife blade in the housing, according to a further feature of the invention, the turning holder is provided at the end with a transverse web, the guide surfaces of which extend parallel to the longitudinal extension and bear against the corresponding guide surfaces of the blade channel, so that the front end in the Front slot of the housing-guided knife blade is also reliably guided in the blade channel in the area of its attachment to the slide, because the guide surfaces formed on the crossbars are guided in the blade channel so that they cannot tip over and rotate.

In a preferred embodiment of the invention, the turning holder is provided with a bearing pin with which it is positioned in a corresponding bearing bore in the slide. According to the invention, the turning holder on the slide can be further fixed in that it is secured against rotation by longitudinal guide webs on the slide.

According to a further feature of the invention, the slide is provided on its underside with at least one latching cam, which engages in a detent formed on the housing with respect to the underside of the slider, from which the latching cam can emerge due to the elasticity of the slide and on which the latching cam by means of a Locking member can be fixed. This further development according to the invention results in a positive locking of the slide on the knife housing, which can only be released consciously and not accidentally; in the known spring catches, which require an additional spring element, which can be lost or broken, an unintentional actuation is not excluded, so that, in contrast to the knife according to the invention, an unwanted release of the knife blade lock can occur. In the case of the invention Training such an incorrect operation is excluded by a positive locking of the slide on the housing, so that the knife according to the invention can also be used for saw blades that are loaded in the pulling and pushing directions.

In a preferred embodiment of the invention, the locking member is formed by a rotatably mounted gag which engages under the catch in the locking position and thus prevents the locking cam from escaping due to the elasticity of the slide and which is dimensioned in the release position such that there is no under-grip. With this design according to the invention there is also the advantage that the detent is arranged on the broad side of the knife housing and thus not in the pressure area of the knife, which is constantly loaded by the thumb or the ball of the thumb during use. This also prevents incorrect actuation of the knife lock and thus unconscious triggering.

In a preferred development, the toggle is formed with a cylindrical middle piece, with which the toggle can be inserted into a slot in the slide provided with circular bearing points. This results in a particularly simple and therefore inexpensive design and storage of the toggle on the slide.

In order to ensure a particularly reliable fixing of the slide on the knife housing, two mutually opposite detents are provided according to the invention.

If, according to the invention, an additional channel for storing reserve knife blades is formed in the housing parallel to the blade channel, a larger number can also be different Knife blades can be reliably stored in the knife.

Finally, the invention proposes to close the housing at its end facing away from the front slot by a cap that closes both the blade channel and the additional channel. This design makes it possible to now form the main part of the knife housing in one piece, so that there is a considerably greater rigidity and strength compared to the previous housings, which are divided in the longitudinal direction.

Fig. 1

eine Seitenansicht des Messers,

Fig. 2

eine Ansicht der anderen Seite des Messers,

Fig. 3

eine Draufsicht auf das Messer,

Fig. 4

eine Stirnansicht des Messers,

Fig. 5

eine der Fig. 2 entsprechende, vergrößert dargestellte Seitenansicht des Messers,

Fig. 6

einen Längsschnitt durch das Messer gemäß der Schnittlinie VI-VI in Fig. 5,

Fig. 7

einen Querschnitt durch das Messer gemäß der Schnittlinie VII-VII in Fig. 5,

Fig. 8

eine Seitenansicht des Schiebers,

Fig. 9

eine Draufsicht auf den Schieber,

Fig. 10

eine Ansicht des Schiebers von unten,

Fig. 11

eine Stirnansicht des Schiebers,

Fig. 12

einen Querschnitt durch den Schieber gemäß der Schnittlinie XII-XII in Fig. 11,

Fig. 13

eine Seitenansicht des Wendehalters,

Fig. 14

eine Draufsicht auf den Wendehalter,

Fig. 15

eine Ansicht des Wendehalters von unten,

Fig. 16

einen Querschnitt durch den Wendehalter gemäß der Schnittlinie XVI-XVI in Fig. 13,

Fig. 17

einen vergrößert dargestellten Längsschnitt durch das Messer im Bereich des Schiebers gemäß der Schnittdarstellung in Fig. 6,

Fig. 18

eine vergrößert dargestellte Draufsicht auf einen Teil des Messers im Bereich des Arretiergliedes,

Fig. 19

eine Draufsicht auf das als Knebel ausgebildete Arretierglied,

Fig. 20

eine Seitenansicht des Knebels,

Fig. 21

einen Schnitt durch den Knebel gemäß der Schnittlinie XXI-XXI in Fig. 20.

An exemplary embodiment of the knife according to the invention is shown in the drawing, namely:

Fig. 1

a side view of the knife,

Fig. 2

a view of the other side of the knife,

Fig. 3

a top view of the knife,

Fig. 4

a front view of the knife,

Fig. 5

3 shows an enlarged side view of the knife corresponding to FIG. 2,

Fig. 6

3 shows a longitudinal section through the knife according to the section line VI-VI in FIG. 5,

Fig. 7

3 shows a cross section through the knife according to the section line VII-VII in FIG. 5,

Fig. 8

a side view of the slide,

Fig. 9

a plan view of the slide,

Fig. 10

a view of the slide from below,

Fig. 11

a front view of the slide,

Fig. 12

3 shows a cross section through the slide according to the section line XII-XII in FIG. 11,

Fig. 13

a side view of the turning holder,

Fig. 14

a plan view of the turning holder,

Fig. 15

a view of the turning holder from below,

Fig. 16

FIG. 13 shows a cross section through the turning holder according to the section line XVI-XVI in FIG. 13,

Fig. 17

6 shows an enlarged longitudinal section through the knife in the area of the slide according to the sectional view in FIG. 6,

Fig. 18

3 shows an enlarged top view of part of the knife in the region of the locking member,

Fig. 19

2 shows a plan view of the locking member designed as a gag,

Fig. 20

a side view of the gag,

Fig. 21

a section through the gag along the section line XXI-XXI in Fig. 20th

The knife shown in Figures 1 to 4 in different views consists of a knife blade M housing 1, which is provided at its front end with a front slot 2 as an outlet for the front end of the knife blade M and at its rear end with a cap 3 is. In the one-piece housing 1, a slide 4 is guided in a longitudinally displaceable manner and can be locked in various positions by means of a toggle 5, which is rotatably mounted on the slide 4 as a locking member, which are predetermined by a detent 6 formed on the housing 1.

The slide 4 is displaceably guided in a guide channel 7 running in the longitudinal direction of the housing 1. This guide channel 7 can be seen in FIGS. 2 and 5 in plan view and in FIG. 7 in cross section. Figures 8 to 12 show the slide 4 in different views and in cross section.

As can be seen from these representations, the slide 4 is provided on its underside with two latching cams 8 which are formed in one piece on a fork-shaped part of the slide 4, this fork-shaped part of the slide 4 being designed to be resilient with respect to the main slide part, which in the exemplary embodiment is a transverse one Material weakening 9 is provided. The material weakening 9 causes the locking cams 8 to emerge resiliently from the recesses of the locking 6 when the slide 4 moves longitudinally relative to the housing 1, so that the slide 4 can be moved in the longitudinal direction of the housing 1.

In order to enable the slide 4 to be locked on the housing 1 in each of those positions in which the locking cams 8 engage in a recess in the locking 6, a locking member in the form of a toggle 5 is provided. This gag 5 is shown as an individual part in FIGS. 19, 20 and 21.

These representations show that the toggle 5 comprises a cylindrical middle piece 10 with which it is rotatably mounted in circular bearing points 11 of the slide 4, these circular segment shaped bearing points 11 being formed in a slot 12 of that part of the slide 4 which has the locking cams 8 . The toggle 5 is provided with a handle 13 on the upper side. On the underside, the middle piece 10 carries a locking part 14; This locking part 14 has different dimensions in the longitudinal and transverse directions, so that the locking part 14 engages under the two catches 6 in the locking position according to FIG. 18, whereas it is dimensioned in its release position rotated by 90 ° in such a way that no grip is present. This has the effect that in this release position the locking cams 8 can emerge from the recesses of the detents 6 and thus the slide 4 can be moved in the longitudinal direction of the guide channel 7, because the part of the slide 4 which bears the locking cams 8 and the toggle 5 resiliently and can thus emerge from the locking recesses. The position of the handle 13 shows whether the toggle 5 is in the locking position according to FIGS. 2 and 5 or in the release position not shown in the drawing. FIG. 17 shows that it is impossible for the locking cams 8 to emerge from the depressions in the associated locking 6 when the toggle 5 is in the locking position because it engages under the locking 6 in this locking position. In the locking position of the toggle 5, the slide 4 is thus positively fixed in the respectively selected position on the housing 1.

As can be seen from FIGS. 10 and 12, the slide 4 is provided with a bearing bore 15 into which a bearing pin 16 of a turning holder 17c engages, which is thus rotatably mounted on the slide 4. This turning holder 17c is provided on the underside facing away from the bearing journal 16 with two journals 18 and 19 with different diameters. These pins 18 and 19 each serve to receive a hole which is formed in the knife blade M to be used in each case. In the exemplary embodiment, the pin 18 has a diameter of 7.1 and the pin 19 has a diameter of 5.2 mm, so that different knife blades M can be held on the turning holder 17c, depending on which of the pins 18 and 19 has been brought into the receiving position .

In order to reliably guide the turning holder 17c in the housing 1, it is provided at each end with a transverse web 20, the guide surfaces 21 of which run parallel to the longitudinal extension of the turning holder 17c are guided in the blade channel 22 of the housing 1, which can best be seen in FIG . In this blade channel there is also the knife blade M, which is held with its hole, which cannot be seen in the drawing, on one of the two pins 18 or 19 of the turning holder 17c.

In the exemplary embodiment shown in the drawing, the turning holder 17c is further fixed in its respective end position on the slide 4 by longitudinal guide webs 23 which are formed on the slide 4 and between which the turning holder 17c is held non-rotatably. These guide webs 23 can be seen in FIGS. 8 to 12.

As can be seen from FIG. 7, an additional channel 24 is formed in the housing 1 parallel to the guide channel 7 for the slide 4 and to the blade channel 22 and can be used for storing spare blades. This additional channel 24 is closed together with the guide channel 7 and blade channel 22 by the closure cap 3 which can be placed on the rear end of the housing 1.

To insert or replace a knife blade M, the closure cap 3 is first removed. Then the gag 5 is rotated by means of its handle 13 such that the grip of the locking part 14 under the catch 6 is lifted. The gripping piece 13 standing transversely in FIGS. 2 and 5 is rotated by 90 ° in this case and extends with its main extent parallel to the longitudinal direction of the housing 1.

In this position, the slide 4 can be pushed back out of the housing 1, since the two locking cams 8 can spring out of the recesses of the detents 6 due to the elasticity of the slide part carrying them. In this way, the slide 4 can be removed from the housing 1 together with the toggle 5 and the turning holder 17c. Outside the housing 1, a knife blade M possibly held on the turning holder 17c can be removed from the turning holder 17c.

The knife blade M now to be used is placed with its hole on one of the two pins 18 or 19 of the turning holder 17c, specifically on the pin 18 or 19 lying in front. If the diameter of the pin 18 or 19 lying in front is not with the hole of the knife blade M to be used, the turning holder 17c with its bearing pin 16 is lifted slightly out of the bearing bore 15 of the slide 4, so that it is outside the guide webs 23 formed on the slide 4. In this position, the turning holder 17c can be rotated through 180 °, so that the pin 18 or 19 required in each case is at the front.

The new knife blade M is now placed on these pins 18 and 19. The blade with the slide 4, the toggle 5 and the turning holder 17c is then pushed into the housing 1, the knife blade M and the turning holder 17c being in the blade channel 22, whereas the slide 4 is essentially in the guide channel 7. Since the gag 5 with its locking part 14 does not engage under the catches 6, the slide 4 can be pushed into the housing 1 until the tip of the knife blade M emerges from the front slot 2 of the housing 1. In the desired position, the slide 4 is then locked with the knife blade M by turning the toggle 5 through 90 °. In this locking position, the locking part 14 of the toggle 5 engages under the catches 6, so that the catch cams 8 lying in a recess of these catches 6 cannot emerge from the recesses when the slide 4 or the knife blade M is axially loaded; there is thus a positive locking of the slide 4 and thus the knife blade M in the respectively selected position.

Both the housing 1 and the slide 4 with toggle 5 and turning holder 17c are preferably made of a suitable one Made of plastic, as is the closure cap 3. In order to be able to hang up the knife when not in use, the housing 1 is provided with a hanging opening 25 in the exemplary embodiment.

Reference list

M

Knife blade

1

casing

2nd

Front slit

3rd

Sealing cap

4th

Slider

5

Gag

6

Rest

7

Guide channel

8th

Locking cams

9

Material weakening

10th

Centerpiece

11

Depository

12th

slot

13

Handle

14

Locking part

15

Bearing bore

16

Bearing journal

17a

holder

17b

holder

17c

Turning holder

18th

Cones

19th

Cones

20th

Crossbar

21

Leadership area

22

Blade channel

23

Boardwalk

24th

Additional channel

25th

Hanging opening

Claims (10)

1. Knife for exchangeable knife blades (M), having a housing (1) and a slide (4) which is guided longitudinally displaceably in the housing (1), can be fixed at predetermined intervals of a latching-notch arrangement (6) formed on the housing (1), and on which the knife blade (M) is retained, such that it can be exchanged, by means of a pin (18, 19) engaging into a hole of the knife blade (M), the respective knife blade (M) being retained on the slide (4) by means of a retaining device (17a, 17b) which is provided with a pin (18 and 19, respectively), corresponding to the hole of the respective knife blade (M), and is mounted on the slide (4) such that it can be exchanged, characterized in that the retaining device is designed as a turn-around retaining device (17c) which is mounted on the slide (4) such that it can rotate through 180° and which is provided, at each end, with a pin (18, 19), the diameters of the two pins being designed in different sizes corresponding to the different commercially available knife blades (M).
2. Knife according to Claim 1, characterized in that the turn-around retaining device (17c) is provided, at the end, with a transverse web (20), the guide surfaces (21), running parallel to the longitudinal extent, of which rest on the corresponding guide surfaces of the blade channel (22).
3. Knife according to Claim 1 or 2, characterized in that the turn-around retaining device (17c) is provided with a bearing pin (16), by means of which it is positioned in a corresponding bearing bore (15) of the slide (4).
4. Knife according to Claims 1 to 3, characterized in that the turn-around retaining device (17c) is secured against rotation by longitudinally running guide webs (23) on the slide (4).
5. Knife according to at least one of Claims 1 to 4, characterized in that the slide (4) is provided on its underside with at least one latching cam (8) which engages into a latching-notch arrangement (6) which is formed, opposite the underside of the slide (4), on the housing (1), out of which arrangement the latching cam (8) can escape, owing to the elasticity of the slide (4), and on which a latching cam (8) can be fixed by means of the locking member (5).
6. Knife according to Claim 5, characterized in that the locking member is formed by a toggle (5) which is rotatably mounted on the slide (4), which, in the locking position, engages beneath the latching-notch arrangement (6) and thus prevents the latching cam (8) from escaping out of the latching-notch arrangement (6), owing to the elasticity of the slide (4), and which, in the release position, is dimensioned such that it does not engage beneath anything.
7. Knife according to Claim 6, characterized in that the toggle (5) is designed with a cylindrical central piece (10), by means of which the toggle (5) can be introduced into a slot (12), of the slide (4), which is provided with bearing points (11) in the form of segments.
8. Knife according to one of Claims 5 to 7, characterized in that two mutually opposite latching-notch arrangements are provided (6).
9. Knife according to at least one of Claims 1 to 8, characterized in that, parallel to the blade channel (22), there is formed an additional channel (24) for accommodating extra blades in the housing (1).
10. Knife according to at least one of Claims 1 to 9, characterized in that, at its end directed away from the end slot (2), the housing (1) can be closed off by a cap (3) which closes off both the blade channel (22) and the additional channel (24).

Images