MXPA04010298A

MXPA04010298A - Utility knife.

Info

Publication number: MXPA04010298A
Authority: MX
Inventors: Jian Ping Qiu
Original assignee: Great Neck Saw Manufacturers
Priority date: 2003-12-31
Filing date: 2004-10-19
Publication date: 2005-07-05
Also published as: FR2864463A1; CA2466621C; GB0412515D0; CA2466621A1; GB2409658B; FR2864463B1; DE102004023870A1; JP2004337612A; NZ533414A; GB2409658A; DE102004023869A1; AU2004202173A1

Abstract

A utility knife having a handle and a blade holder which is pivotally mounted on the handle for movement from an unfolded position to a folded position. The handle has a space adapted to receive the blade holder when the blade holder is in its folded position. The blade holder includes a main wall and guard wall pivotally mounted on the main wall to pivot from an open position to a closed position overlying the main wall. The main wall being adapted to hold a blade so that a blade is interposed between the main wall and guard wall when the guard wall is in its closed position.

Description

UTILITY KNIFE RELATED APPLICATION This is a continuation in part of the North American Patent Application No. 10 / 437,089 filed on May 13, 2003. BACKGROUND OF THE INVENTION The present invention relates to a utility knife and more particularly to a knife of foldable props where the blade can be folded into the handle when the knife is not in use. Utility knives have been used for many years. Some of the utility knives in use have blades mounted on a blade holder that can be bent into the handle when the knife is not in use. However, some of these utility knives have many moving parts which makes their use difficult and expensive to manufacture. In addition, in some of these utility knives, replacing the blade is a complicated operation that may require special tools. OBJECTS OF THE INVENTION The present invention solves these problems and has as one of its objects the provision of an improved utility knife wherein the sheet holder can be easily bent in the handle. Another object of the present invention relates to the provision of an improved utility knife wherein the blade is held firmly in the utility knife. Another object of the present invention is the provision of an improved utility knife wherein improved means for replacing the blade in the utility knife is provided. Another object of the present invention is the provision of an improved utility knife that is easy to use and economical to manufacture and maintain. Other additional objects of the present invention will be apparent upon understanding the illustrative embodiment described below or they will be indicated in the appended claims and various advantages not mentioned herein will be devised by a person skilled in the art when employing the invention in practice. . BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the present invention has been selected for purposes of illustration and description and is shown in the accompanying drawings that form part of the specification, wherein: Figure 1 is a perspective view of a utility knife; utility manufactured in accordance with the present invention; Figure 2 is a top plan view thereof; Figure 3 is a sectional view along line 3-3 of Figure 1; Figure 4 is a sectional view similar to Figure 3 showing a utility knife in the partially bent position; Figure 5 is a sectional view similar to Figure 3 showing the utility knife in the fully folded position; Figure 6 is a plan view of one side of the utility knife showing how to remove and replace the blade; and Figure 7 is a plan view of the opposite side of the utility knife. PREFERRED MODALITIES With reference to the drawings, the utility knife 1 of the present invention comprises a handle 2 and a sheet fastener 3. The handle 2 comprises a pair of handle halves 2A and 2B each having an outer side wall 11 and an upper edge 7 and a lower edge 9. A rear spacer 4 is provided between the handle halves 2A and 2B to hold the handle halves 2A and 2B apart and to create a space 5 between the handle halves 2A and 2B. The spacers 4 and the handle halves 2A and 2B are held together by fasteners 6 which pass through the spacer 4 and the handle halves 2A and 2B in order to hold them together. The upper edge 7 of the handle halves 2A and 2B (ie, the handle 2) has a notch for finger 8 and the lower edge of the handle halves 2A and 2B (i.e., the handle 2) which represents undulations for allowing the fingers of the user to grip the handle 2. If desired, a fastener 10 can be mounted on a side wall 11 of the handle halves 2A and / or 2B for allowing the utility knife 1 to be held on the user's belt or other convenient location. Interposed between the handle halves at 2A and 2B and along the upper edges 7 of the handle halves 2A and 2B there is provided a block lever assembly 15 (Figures 3 to 5) pivotally mounted between the halves of the handle halves. handle 2A and 2B on a pivot pin 16 extending through the two handle halves 2A and 2B and the lock lever assembly 15. The lock lever assembly 15 is a two-arm lever having an arm frontal 17 and a rear arm 18, respectively. The front arm 17 is equipped with a locking finger 19 extending downwards. Beneath the rear arm 18 of the locking lever assembly 15 is provided a spring 14 (having a u-shaped shape) which normally rests against the lower edge of the rear arm 18 to push the rear arm 18 upwards and the arm front 17 down around the pivot 16 in such a way that the rear arm 18 protrudes above the notch 8. It will be noted that when the rear arm 18 of the locking lever assembly 15 is pressed down manually through the notch 8 against the spring action 14, the front arm 17 is raised. of sheet 3 of the present invention comprises a rear end 31 and a front end 32 integrated therebetween. The trailing end 31 of the sheet fastener 3 has a trailing edge 31A, a lower edge 3IB and an upper edge 31 C. The sheet fastener 3 is pivotally mounted in the space 5 between the handle halves 2A and 2B in a pivot pin 30. A finger button 41 can be provided at the rear end 81 to facilitate the pivotal movement of the sheet fastener 3 relative to the handle 2. The upper edge 31 C of the rear end 31 has a slot 33 in which the locking finger 19 extending downwardly of the locking assembly 15 is adapted to penetrate when the sheet fastener 3 is in its extended or non-bent position. The front end 32 of the sheet fastener 3 comprises a thin main wall 34 and a thin protective wall 35 mounted in pivoting fashion on the main wall 34 in the pivot pin 36. The main wall 34 is adapted to have a leaf B having a lower cutting edge 37 and spaced notches 38 at its upper edge 39. The main wall 34 has a pair of spaced protuberances 40 extending therefrom in which the upper notches 38 of the sheet B are adapted to penetrate to retain the blade B in place in the main wall 34. It will be noted that when the protective wall 35 is in its closed raised position, it covers and holds the blade B in place but when in its open position downwards, exposes the blade B. A blade locking assembly 45 is mounted along the upper edge 35 of the blade fastener 30 and is pivotally mounted to the front end 32 of the blade fastener 30 in a continuous manner. n pivot bolt 46. The blade locking assembly 45 is in the form of a u-shaped fastener having a segmented or interrupted upper wall 48, a pair of side walls 49 depending on the upper wall 48 and a tongue of lateral finger 50 that extends outward from there. When the sheet locking assembly or fastener 45 pivots downwardly around the pivot 46, its side walls 49 encompass the walls 34 and 35 of the sheet fastener 3 and its upper wall 48 covers the walls 34 and 35 as well as the sheet B with the object of folding the B sheet in its place. Inwardly extending projections 51 may be provided in the side walls 49 to frictionally engage the main wall and the protective wall 34, 35 to hold the block assembly 45 in place. When it is desired to renew and replace the blade B, the fastener 45 is pivoted upwardly through its finger tab 50 in order to free the walls 34, 35 and the blade B. This allows the protective wall 35 to be pivoted away from sheet B (as shown in Figure 6) in order to expose sheet B and allow sheet B to be removed and replaced. In operation, the utility knife 1 is placed in its un-bent operative position with the leaf holder 3 unfolded and ready for use. The blade B is maintained in the main wall 34 by protuberances 40 extending in notches 38 in the upper edge 39 of the sheet B. the locking finger 19 of the The front arm 17 of the block lever assembly 15 is in the lowest position (due to the pressure of the spring 14 on the rear arm 18) and is placed in the slot 33 in the sheet holder 3 in order to maintain the fastener of sheet 3 in its unfolded position. The rear arm 18 of the locking lever assembly 15 is in its raised position and protrudes above the finger groove 8 in the upper edge 7 of the handle 2. When it is desired to place the utility knife 1 in its bent position it does not operative, the rear arm 18 of the block assembly 15 is pressed down manuathrough the notch 8 against the pressure of the spring 14. This causes the front arm 17 of the locking assembly 15 to be raised thereby displacing the finger block 19 outside the slot 33 to release the blade holder 3 and allow it to pivot downwardly around the pivot pin 30 (Figure 4). This can be achieved by pushing down the finger button 41. The leaf holder 3 is then pivoted fudown in the space 5 between the handle halves 2A and 2B (Figure 5). When the pressure of the rear arm 18 is released, the spring 14 moves the rear arm 18 to its original raised position through the tension of the spring 14. This causes the locking finger 19 to bear against the trailing edge 31 A and the lower edge 31 B of the sheet holder 3 thus maintaining the sheet holder 3 in its bent position. When you want to use sheet B, the reverse procedure is followed. The sheet holder 3 is pivoted in the opposite direction. It may be desirable for the rear arm 18 of the locking lever assembly 5 to be manuadepressed again to assist in unfolding the sheet holder 3. The sheet holder 3 is still rotated counterclockwise (as shown in FIG. can be seen in Figure 4) until the locking finger 19 of the front arm 17 enters the slot 33 at the rear end 31 of the blade holder 3 in order to keep the blade holder 3 in its extended position. When it is desired to replace a blade B, the blade fastener 3 is placed in its unfolded position (as shown in Figure 6) and the fastener 45 is lifted around the pivot 46 by means of the finger tab 50 thereby releasing the protective wall 35 and allowing it to pivot down about the pivot 36 to expose the sheet B. The sheet B can then be removed from the sheet holder 3 and another sheet B can be placed there. The protective wall 35 is again pivoted upward to the position on top of the blade B and the fastener 45 is lowered to lock the blade B and the walls 34 and 35 in place. It will be noted that the present invention offers a utility knife wherein the blade holder can be easily bent in the handle and where improved means for securing the blade on the utility knife and replacing the blade in the knife and providing It is simple to use and economical to manufacture and maintain. Since many varied modifications of the subject matter of the present invention will be apparent to those skilled in the art from the detailed description given above, it will be understood that the present invention is limited only by that indicated in the appended claims.

Claims

CLAIMS A utility knife comprising a handle and a blade holder, said blade holder is pivotally mounted on said handle for movement from a unfolded position to a bent position, said handle having a space adapted to receive at least a part of said blade holder when the blade holder is in its bent position, said blade holder comprises a main wall and a protective wall pivotally mounted on said main wall from an open position to a closed position covering said main wall, said main wall has a means to hold a sheet there so that a sheet is interposed between said main wall and said protective wall when said protective wall is in its closed position, said sheet fastener comprises a rear end and a front end, said front end comprises said protective wall and dic The main wall, said rear end is pivotally mounted on said handle and has an upper edge and a lower edge, said protective wall is pivotally mounted on said main wall in a pivot adjacent to the lower edge of said rear end, A blade block assembly is mounted for pivoting movement relative to said main wall and said protective wall, from an open position towards a closed position covering the main wall and the protective wall, said locking assembly The blade is pivotably mounted on said front end adjacent said top edge. A utility knife according to claim 1, wherein said blade locking assembly comprises a "u" -shaped fastener having an upper wall and a pair of side walls, and wherein said side walls encompass said main wall and a protective wall when a fastener is placed in a closed position A utility knife according to claim 2, wherein said fastener has a front finger extending therefrom. as set forth in claim 3, wherein said rear end has a finger button extending therefrom. A utility knife in accordance with claim 4, wherein said handle comprises a pair of spaced apart halves of handle and wherein said handle has a pivoted locking lever assembly mounted in said space in the handle and wherein said lever assembly Lock has a front arm and a rear arm and a locking finger that extends from your front arm. A utility knife according to claim 5, wherein said rear end of the blade holder has a slot there adapted to receive said locking finger wherein the blade holder is in its unfolded position. A utility knife according to claim 6, wherein spring means are mounted under the rear arm of the locking lever assembly to push the rear arm upward and to push the front arm downward to allow the The locking finger enters the slot, so pressing the rear arm against the tension of the spring means will cause the front arm to rise and for the locking finger to come out of the slot, which allows the retainer pivot blade relative to the handle from a unfolded position to a folded position in the space in the handle. A utility knife according to claim 7, wherein the handle has a notch in its upper edge and where the rear arm protrudes above the notch so that pressing the rear arm in the notch allows that the front end is raised upwards and causes the locking finger to come out of the locking slot. A utility knife in accordance with claim 8, wherein the blade fastening means comprises a pair of protuberances in the main wall of the blade fastener, said protuberances being adapted to penetrate corresponding slots in a blade. A utility knife according to claim 9, wherein inwardly extending projections are provided on the side walls of said locking assembly to frictionally hold the locking assembly in place. A utility knife comprising a handle and a blade holder, said blade holder is pivotally mounted on said handle for movement from a unfolded position to a bent position, said handle having a space adapted to receive at least one part of said blade holder when the blade holder is in its bent position, said blade holder comprises a main wall and a protective wall mounted on said main wall and which can be moved from an open position to a closed position covering said main wall, said main wall has a means to hold a sheet there so that a sheet is interposed between said main wall and said protective wall when said protective wall is in its closed position, said sheet fastener comprises one end back and a front end, said front end comprises said protection wall and said wall prin cipal, wherein said rear end is mounted as a pivot on said handle and has upper and lower edges, a blade locking assembly is mounted for pivoting movement relative to said main wall and said protective wall from an open position towards a closed position covering the main wall and the protective wall, said sheet locking assembly is pivotally mounted on said front end adjacent said upper edge. A utility knife according to claim 11, wherein said blade locking assembly comprises a "u" shaped fastener having an upper wall and a pair of side walls and wherein said side walls cover said Main wall and a protective wall when a fastener is in its closed position. 3. A utility knife according to claim 12, wherein said fastener has a front finger extending therefrom. 4. A utility knife according to claim 13, wherein said rear end has a finger button extending therefrom. A utility knife according to claim 14, wherein said handle comprises a pair of spaced handle halves and wherein said handle has a lock lever assembly pivoted in said space in the handle, and in wherein said locking lever assembly has a front arm and a rear arm and a locking finger extending from its front arm. 6. A utility knife according to claim 15, wherein said rear end of the blade holder has a slot there adapted to receive said locking finger when the blade holder is in its unfolded position. A utility knife according to claim 16, wherein spring means is mounted under the rear arm of the locking lever assembly to push the rear arm up and to push the front arm downward with the purpose of Allowing the locking finger to penetrate the slot, whereby pressing the rear arm against the tension of the spring means will cause the front arm to rise and the locking finger to move out of the slot allowing the blade holder pivoted relative to the handle from an unfolded position to a folded position in the space in the handle. A utility knife according to claim 17, wherein the handle has a notch on its upper edge and wherein the rear arm protrudes above the notch so that pressing the rear arm into the notch allows that the rear arm is raised upwards and causes the locking finger to come out of the locking slot. A utility knife according to claim 18, wherein the blade fastening means comprises a pair of protuberances in the main wall of the blade fastener, said protuberances being adapted to penetrate corresponding slots in a blade. A utility knife according to claim 19, wherein inwardly extending projections are provided on the side walls of said locking assembly to frictionally hold the locking assembly in place.