Patent Application
20100088900
This disclosure relates to cutting rigid and semi-rigid materials, and more particularly, to cutting rigid and semi-rigid materials with a utility cutter including an integral trigger lock.
Utility cutters may be used to cut or slice a variety of materials, such as cardboard, corrugated board of varying thickness, rubber, lightweight plastic, or other packaging material. In order to cut or slice such material, the utility cutter may need to have a sharpened blade. Certain precautions may be used to protect or help protect a user from the sharpened blade. For example, a utility cutter may include guards that extend from the cutter alongside the sharpened blade, such that the guards substantially prevent an accidental injury to the user or other bystander. Further, a utility cutter may include a protective handle that encloses substantially all of a blade during periods of non-use. Utility cutters, however, may be actuated accidentally even during periods of storage or non-use. Accidental actuation of a utility cutter, therefore, may present a substantial hazard to the user, other persons, or valuable material.
Utility cutters are also often moved between and among many locations by users. Use of a utility cutter in a packaging or shipping environment, for example, may subject the utility cutter to periods of use and non-use at various locations, including such locations as vehicles or storage areas. Loss of utility cutters due to the transient nature of their use could mean a significant loss of economic value to an individual or business enterprise. Cost-efficient utility cutters, which effectively cut or slice a variety of material but do not represent a large outlay of economic resources, may have significant value to a business enterprise.
In one general implementation, a utility cutter includes a housing, a blade connected to a blade shuttle, a shuttle spring, a blade trigger, and a trigger lock. The housing includes a blade aperture, a trigger aperture, and a stop pin. The blade and blade shuttle are substantially enclosed within the housing when the blade shuttle is in a retracted position, where the blade is extended from the housing when the blade shuttle is in an extended position. The shuttle spring is connected to the blade shuttle and adapted to convey the blade shuttle to the retracted position. The blade trigger includes a cavity and is pivotally coupled to the housing and accessible at an exterior of the housing through the trigger aperture. The blade shuttle is conveyed from the retracted position to the extended position when the blade trigger pivots from a rest position to an engaged position. The trigger lock includes a projection and is substantially enclosed within the cavity and accessible at the exterior of the housing through the blade trigger. The trigger lock is pivotally coupled to the blade trigger and the projection is in contact with the stop pin when the blade shuttle is in the retracted position. The blade trigger is substantially prevented from pivoting from the rest position to the engaged position when the projection is in contact with the stop pin and the projection is released from the stop pin upon rotation of the trigger lock. The blade trigger is pivotable from the rest position to the engaged position when the projection is released from the stop pin.
In some specific aspects of the utility cutter, the blade shuttle may be adapted to move from the extended position to a cutting position when the blade is engaged in a workpiece. The blade may extend further from the blade aperture in the cutting position than in the extended position. The shuttle spring may automatically convey the blade shuttle from the cutting position to the retracted position when the blade is disengaged from the workpiece. Additionally, the shuttle spring may be adapted to automatically convey the blade shuttle from the cutting position to the retracted position when the blade is disengaged from the workpiece when the blade trigger is in the engaged position. Further, the blade trigger may be adapted to pivot from the rest position substantially simultaneous to rotation of the trigger lock.
In certain specific implementations, the blade trigger may include a cleft and the trigger lock may include a notch. The notch may be adapted to engage the cleft upon rotation of the trigger lock and transfer rotational motion from the trigger lock to the blade trigger. The blade trigger may be adapted to rotate from the rest position to the engaged position when the notch engages the cleft. Additionally, the utility cutter may further include a transmission adapted to transfer a rotational force of the blade trigger as it rotates from the rest position to the engaged position to a lateral force, where the lateral force is directed to convey the blade shuttle from the retracted position to the extended position. In specific aspects, the blade shuttle may include a spring tongue and the blade trigger may further include a rail. The transmission may include at least one guide integrally formed in an interior surface of the housing; a lever coupled to the housing; and a drive arm coupled to the lever. The lever may include at least one lever pin adapted to move along the rail as the blade trigger rotates from the rest position. The drive arm may include a pin and a notch, where the pin is adapted to engage the guide and slide within the guide when the blade trigger rotates from the rest position. The notch is adapted to engage the spring tongue when the blade trigger rotates from the rest position and convey the blade shuttle from the retracted position to the extended position when the blade trigger rotates from the rest position to the engaged position. The spring tongue may be adapted to bend while engaged with the notch when the blade shuttle moves from the retracted position to the extended position. Further, the spring tongue may be adapted to disengage from the notch when the blade shuttle moves from the extended position to a cutting position. In some aspects, an angle between the drive arm and the lever may be between approximately 70 degrees and approximately 90 degrees
In particular aspects of the utility cutter, the utility cutter may further include a spring post integral to the housing and a lever spring. The lever may be coupled to the housing via the spring post. The lever spring may be coupled to the spring post and the lever, where the lever spring is adapted to apply a torsional force to the lever and convey the blade trigger from the engaged position to the rest position via the transmission.
In certain embodiments, the shuttle spring may exert no force on the blade shuttle when the blade shuttle is in the retracted position. Further, the utility cutter may include a trigger spring, where the trigger lock may be in a locked position when the projection is in contact with the stop pin and an unlocked position when the projection is released from the stop pin. The trigger spring may urge the trigger lock from the unlocked position to the locked position. In some aspects, the trigger spring may be an integral spring extension of the trigger lock. In various aspects, the trigger spring may be a compression spring coupled to one of the trigger lock and the blade trigger. The trigger lock may be adapted to receive a compressive force to convey the trigger lock from the locked position to the unlocked position, where the blade trigger may be adapted to receive the compressive force to convey the blade trigger from the rest position to the engaged position.
The utility cutter may include a clip coupled to the housing. The clip may be coupled to either side of the housing. The housing may include a front housing edge at the blade aperture and a front contour. A plane tangential to the front housing edge and a plane tangential to a cutting edge of the blade may define a first obtuse angle. A plane tangential to the front contour and a plane tangential to the blade may define a second obtuse angle. The first obtuse angle and the second obtuse angle may define a compound angle of cut.
In certain aspects, the blade trigger may include a front portion and a back portion, where the front portion is nearest the blade aperture. The front and back portions may each define approximately one-half a length of the blade trigger. The trigger lock may be accessible at the exterior of the housing through the back portion of the blade trigger.
The blade of the utility cutter may include a mount hole and the blade shuttle may include an integral detent formed in a blade slot. The blade may be adapted to slide into the blade slot and engage the integral detent with the mount hole. The integral detent may include a leading edge and a back edge. The leading edge may be tapered from a base of the detent to a top of the detent, where the back edge may be substantially perpendicular to the blade shuttle. The blade may be adapted to engage the integral detent with the mount hole over the leading edge. The back edge may be adapted to substantially prevent decoupling of the blade from the blade shuttle.
Various implementations of a utility cutter according to the present disclosure may include one or more of the following features. The utility cutter may provide a safer cutting mechanism by substantially preventing accidental blade extensions. The utility cutter may provide a more ergonomic and comfortable fit for a user of the cutter. The utility cutter may include a locking mechanism that substantially prevents a blade from accidentally being extended from the cutter. Also, the locking mechanism of the utility cutter may allow for blade extension substantially simultaneous with unlocking. The utility cutter may automatically retract a blade used for cutting or slicing a workpiece into a protective handle when the blade becomes disengaged from the workpiece. Furthermore, the utility cutter may allow for a substantially constant force to extend a blade from a fully retracted position to a fully extended position. Additionally, the utility cutter may provide for a lightweight and disposable mechanism for cutting or slicing rigid or semi-rigid materials.
Various implementations of a utility cutter according to the present disclosure may also include one or more of the following features. The utility cutter may allow for less energy and effort to be utilized when slicing or cutting material through a compound angle of cut. The utility cutter may allow for reduced friction on a blade of the cutter thereby increasing the life of the blade. The utility cutter may allow for reduced friction on a blade of the cutter thereby allowing for a cleaner cut of a rigid or semi-rigid workpiece. The utility cutter may utilize a friction force between a blade of the cutter and a workpiece to allow for automatic retraction of the blade into a retracted position in the cutter. Also, the utility cutter may ensure that a mechanical action of the cutter experiences minimal malfunctions by reducing contaminants from entering the cutter. Additionally, the utility cutter may include a two-piece assembly housing that prevents user access to an interior of the assembly housing in order to avoid internal contamination. The utility cutter may include a two-piece assembly housing held together by security screws requiring specialized tooling to access the interior of the assembly housing, thereby preventing or minimizing internal contamination and malfunction. The utility cutter may allow a user to more comfortably cut rigid or semi-rigid material without substantially injury. The utility cutter may be actuated with approximately 75% less force than typical utility cutters. The utility cutter may also substantially prevent injuries or workplace hazards due to loose cutting blades. The utility cutter may also more easily be carried or otherwise transported in a user's pocket or secured to an article of clothing.
These general and specific aspects may be implemented using a device, system or method, or any combinations of devices, systems, or methods. The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
The figures and following description illustrate and explain a utility cutter 10, which may be used to cut rigid or semi-rigid materials, such as, for example, corrugated board, cardboard or other paper products, rubber, plastic, Styrofoam, or any other appropriate material. The utility cutter 10 is typically a handheld device operated by either a left-handed or right-handed user with equal ease. In some implementations, the utility cutter 10 allows the user to carry, transport, or otherwise handle the cutter 10 in a back position, whereby a sharpened blade of the cutter 10 is locked in a retracted position within a protective housing or handle. The user may, as appropriate, set the cutter 10 into an unlocked position via an integral trigger lock within a blade trigger. Further, the user may, substantially simultaneous to placing the utility cutter 10 into the unlocked position, easily and ergonomically actuate the blade trigger to extend the sharpened blade from the protective handle. Once the user finishes cutting the material as desired, the user may disengage the blade from the material. Once disengaged, the blade may be automatically retracted within the protective handle by a spring force to ensure that the blade is no longer exposed and able to cause injury to the user or other person, and/or the material previously cut. This automatic retraction of the blade may occur regardless of whether the blade trigger remains actuated by the user.
The housing, or handle, 15, of the utility cutter 10 encloses at least a portion of the components of the cutter 10 within a protective enclosure. Typically, the housing 15 may be manufactured as a stamped and extruded molded case (e.g., GF nylon), but alternatively, may be made of any appropriate rigid or semi-rigid material. For example, the housing 15 may be made from aluminum or steel, such as stainless steel, in certain implementations. The housing 15, however, may be made of a lightweight and cost efficient material such that the utility cutter 10 may be disposed of upon its end of life without significant economic loss.
Further, the housing 15, generally, may be a two-piece housing such that identical or substantially identical halves of the housing may be coupled together to enclose the components of the utility cutter 10. As a two-piece configuration, the housing 15 may be coupled together through mechanical means, such as screws, rivets, or a snap fit, or through adhesive material. In some aspects, the two halves of the housing 15 may be coupled together using specialty screws, such that a user of the utility cutter 10 may require a special tool to decouple the halves of the housing 15.
The housing 15 includes a blade aperture 75, which allows the blade 55 to extend from the housing 15 when the cutter 10 is actuated. In certain implementations, such as when the housing 15 includes a two-piece design, the blade aperture 75 may be formed at a distal end of the cutter 10 when the two halves of the housing 15 are coupled together. Further, the housing 15 includes an aperture along a bottom side of the housing 15 through which the blade trigger 20 may extend. Additionally, in some aspects, the housing 15 may include one or more integral protrusions extending from an interior wall of the housing 15 into the cavity formed by the two-piece enclosed housing 15. For example, in some aspects, the housing 15 may include a stop pin 30, a spring post 38, a body pin 52, and a slot 70. In some implementations of the housing 15, each half of the housing 15 may include a stop pin 30, a spring post 38, a body pin 52, and a slot 70. In such implementations, for example, the two stop pins 30, the two spring posts 38, and the two body pins 52 may meet in approximately the middle of the cavity formed in the housing 15. Alternatively, two stop pins 30 and two body pins 52 may be included that meet in approximately the middle of the cavity formed in the housing 15, while a single spring post 38 and a single slot 70 are included. In some implementations of the utility cutter 10, the stop pin 30 and the spring post 38 may be combined into one protrusion extending into the cavity and incorporating the functions described herein for these components.
Continuing with
The trigger lock 25 is pivotally coupled to the blade trigger 20 at one or more lock pivots 27, and is substantially seated within the blade trigger 20. Generally, a portion of the trigger lock 25 extends through an aperture formed in the blade trigger 20 and to the exterior of the housing 15, thereby allowing access to the trigger lock 25 by the user of the utility cutter 10. In the back position, at least a portion of the trigger lock 25 is in contact with the stop pin 30. For example, as illustrated in
In some implementations of the utility cutter 10, the trigger lock 25 is positioned such that the lock 25 extends through an aperture formed in a back half of the blade trigger 20 furthest from the blade aperture 75 to the exterior of the housing 15. In such implementations, the user of the utility cutter 10 may grip the blade trigger 20 and the trigger lock 25 simultaneously, with one or more fingers positioned on the trigger lock 25. For example, the user may naturally and ergonomically grip the utility cutter 10 such that the user's third and/or fourth fingers may be positioned on the trigger lock 25 while the user's first and second fingers are positioned on the front half of the blade trigger 20. The user's thumb is typically placed around a top edge of the housing 15 during operation and handling of the utility cutter 10. As explained in more detail with reference to
Lever 40 is an elongated member that is coupled at one end to the housing 15 via the spring post 38. An opposite end of the lever 40 includes one or more lever pins 42 protruding from the lever 40. In some implementations, the lever 40 extends into the cavity of the blade trigger 20 while lever pins 42, extending from either side of the lever 40, are seated upon the rails 24 of the blade trigger 20. In the back position, in the implementation illustrated in
A lever spring 35 is coupled to the lever 40 at one end through a small aperture in the body of the lever 40 and is wound around the spring post 38. A free end of the lever spring 35 is set against the body pin 52, thereby providing a spring force against the lever 40. The lever spring 35, therefore, acts to force the lever 40 into the back position shown in
In the implementation shown in
With regards to the drive arm 45, in some implementations of the utility cutter 10, this component may be set between approximately 70 and 90 degrees (e.g., 82 degrees) from the lever 40 when the utility cutter 10 is in the back position shown in
Continuing with the implementation of
As more fully explained with reference to the implementation show in
Blade 55 is typically formed of steel with a sharpened cutting edge 80 and a rounded safety point at the leading end of the cutting edge 80. Further, the blade 55 typically includes a trapezoidal end and a substantially rectangular end, as shown in
The blade 55 may be coupled to the blade shuttle 50 through mechanical means, such as a screw or rivet, or alternatively, may be attached to the blade shuttle 50 through adhesive means. In some implementations of the utility cutter 10, as more fully shown in
As shown in the implementation of
Continuing with the implementation shown in
As further shown in
The implementation reflected in
As shown in
The forward movement of the drive arm 45 may be transferred to the blade shuttle 50 through the spring tongue 65 engaged with the notch end of the drive arm 45. The spring tongue 65 may, in some aspects, bend downward as the drive arm 45 exerts a forward-directed force on the blade shuttle 50, but, typically, stays engaged with the drive arm 45 while the blade shuttle 50 moves from its retracted position to its extended position.
As shown in
In some implementations of the utility cutter 10, an angle between the drive arm 45 and the lever 40 may be between approximately 70 degrees and approximately 90 degrees when in the retracted position. An initial force necessary to begin rotation of the blade trigger 20 and overcome the inertia of the components of the cutter 10 in the back position may therefore be substantially equal to a force required to extend the blade 55 from the housing 15 once the components of the cutter (e.g., blade trigger 20, lever 40, drive arm 45, and blade shuttle 50) are set in motion. For example, the initial force required to rotate the blade trigger 20 may be approximately 8 ounces while the force required to extend the blade 55 may be between approximately 7-8 ounces. In such fashion, the user of the utility cutter 10 may expend less energy in actuating the cutter 10, thereby allowing for more ease of use and less chance of injury from use of the cutter 10.
The implementation shown in
In one implementation, once the blade 55 become disengaged from the workpiece 85 and the frictional force no longer exists between the workpiece 85 and the blade 55, the shuttle spring 60 uncoils to automatically retract the blade shuttle 50 from its cutting position to its retracted position. More specifically, the shuttle spring 60 is compressed as the blade shuttle 50 moves from the retracted position to the extended position. When the frictional force on the blade 55 becomes less than the spring force of the shuttle spring 60, the spring 60 exerts the spring force on the shuttle pin 62 via the spring rod 95. The spring force exerted on the shuttle pin 62 by the shuttle spring 60 may be transferred to the blade shuttle 50, thereby returning the blade shuttle 50 to its retracted position.
In some aspects of the utility cutter 10, the blade shuttle 50 may return to its retracted position when the blade trigger 20 is actuated. As shown in the implementation of
Alternatively, if the blade trigger 20 is in the unactuated position (as shown in
Continuing with the implementation of
In some implementations, the utility cutter 500 may include a trigger lock 525, which includes a cylinder 528. The blade trigger 520 may further include a piston 526 attached to or formed integrally with the blade trigger 520. The utility cutter 500 may further include a piston spring 527. Generally, the cylinder 528, the piston 526, and the piston spring 527 may function in concert to return the trigger lock 525 from an unlocked position to a back position when the blade trigger 520 is released from an actuated position. For example, in the unlocked position, the trigger lock 525 may be rotated such that the piston 526 fits into the cylinder 528, thereby compressing the piston spring 527 within the cylinder 528. In a compressive state, the piston spring 527 may apply a force to the trigger lock 525 thereby urging the lock 525 into the back (and locked) position. In another aspect, the piston 526 and the cylinder 528 may be substantially similar in dimensions, such that the piston spring 527 may be compressed between the piston 526 and the cylinder 528 when the trigger lock 525 is in the unlocked position. Alternatively, in other implementations, the piston spring 527 may be integral to the cylinder 528. The piston spring 527, generally, may apply no force to the trigger lock 525 or blade trigger 520 when the trigger lock 525 is in the back position.
A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. Accordingly, other implementations are within the scope of the following claims.
