HK1134767B - Safety scalpel with replaceable blade cartridge and safety brake - Google Patents

Description

Safety scalpel with replaceable blade cartridge and safety brake

It is to be appreciated that the U.S. legal residents who live in Edinburgh 8895, Roxwell, George, Singapore, Patrick, and Vietnam citizen, Li, who live in valley 474A, Singapore 248359, have invented some novel and useful improvements.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PHARMACEUTICAL APPLICATIONS

This application is a partial continuation of U.S. patent application No.11/259,939, filed on 26/10/2005, which claims priority from U.S. provisional patent application No.60/623,741, filed on 29/10/2004.

Technical Field

The present invention relates generally to scalpel devices, and more particularly to medical safety scalpels.

Background

Healthcare is the second fastest growing segment of the U.S. economy, employing over one thousand and two million workers. Health care workers face a wide range of risks at work, including needlestick and sharps injuries, back injuries, latex allergies, violence and stress. While it is possible to prevent or reduce the risk to which healthcare workers are exposed, healthcare workers are actually experiencing increasingly more occupational injuries and illnesses. The proportion of occupational injuries to health care workers has risen over the past decade. In contrast, two of the most hazardous industries, agriculture and construction are now safer than ten years ago.

Accurate national data is not applicable to annual data for needle sticks and other percutaneous injuries by health care workers, however, estimates show that 600,000 to 800,000 such injuries occur annually. About half of these lesions have not been reported. Data from EPINet (blood exposure prevention and treatment advisory network system) suggests that in a general hospital, approximately thirty needle injuries occur per 100 beds per year for staff.

Most reported needle and sharps injuries involve nursing staff, but laboratory staff, physicians, housewives, and other health care workers are also injured. Some of these injuries expose workers to blood-borne pathogens that can cause infection. More serious of these pathogens are Hepatitis B Virus (HBV), Hepatitis C Virus (HCV) and Human Immunodeficiency Virus (HIV). Infection by each of these pathogens can be life-threatening, but can be prevented.

The emotional impact of needle sticks and sharps injuries is severe and persists for long periods of time, even if severe infections are not transmitted. This effect is particularly acute when the injury involves exposure to HIV. In one study in which twenty healthcare workers were exposed to HIV, eleven reported severe distress, seven had persistent moderate distress, and six resignated to work from the exposure. Other stress responses requiring counseling have also been reported. It is unknown that the infectious state of the source patient can put stress on the health care provider. In addition to the exposed health care workers, colleagues and families may also suffer emotionally.

Safety and hygiene issues are best addressed by setting up a comprehensive prevention plan that considers all aspects of the work environment and has personnel involved and regulatory commitments. The use of implementing improved engineering controls is part of such a comprehensive plan. However, other control measures factors that must be addressed include: modifying hazardous work management, addressing administrative changes to needlestick hazards in the environment (e.g., immediate removal of boxes full of needlestick waste), safety education and attention, feedback on safety improvements, and actions to consider persistent issues.

Improved engineering control is often the most effective way to reduce occupational hazards and is therefore an important factor in needle-stick control programs. Such control includes eliminating the use of unnecessary needles and implementing a device with a safety feature. Numerous sources have identified several desirable characteristics for security devices, including preferences for security devices: no needle is used; the safety device is taken as a component of the device; passive operation (i.e., no user activation required); a safety feature that is usable with one-handed techniques and allows a worker's hand to be located on the exposed needle rear surface if user activation is required; to allow a user to easily determine whether the safe is activated; having a safety that cannot be disabled and remains protective when discarded; reliable execution; easy to use and practical; safe and effective for patient care.

While each of these characteristics is desirable, some are not feasible, applicable or available for a particular healthcare situation. For example, for the case of no alternatives for skin penetration, a needle is always necessary. Additionally, a safety feature that requires activation by a user may be preferred for individuals that are passive in certain situations. Each device must take into account its own advantages and its ability to ultimately reduce workplace injuries.

For a particular scalpel, conventional scalpels currently used in the health care industry include a metal handle and a disposable blade mounted to the handle prior to use and removed from the handle after use. The blade mounting and dismounting process is a difficult and dangerous process that exposes the medical practitioner to potential injury from the exposed blade or contamination from blood on the blade. Further, sharps injuries may also occur during procedures in which the surgeon passes exposed scalpel to colleagues.

Surgeons who are familiar with the feel of the weight and shape of metal handles dislike current disposable safety scalpels, especially because plastic handles are too light and feel "different". The plastic handle of the scalpel causes undesirable flexibility during use compared to a metal handle scalpel. In addition, disposable safety scalpels are significantly more expensive than conventional disposable blades. These two factors currently limit the use of safety scalpels in the health care industry.

There is therefore a need for a safe and reliable scalpel that overcomes the drawbacks of health care practitioners with respect to the feel of current designs, while providing adequate protection for the medical staff holding the scalpel. Such devices are of primary interest to the present invention.

Disclosure of Invention

Briefly, in accordance with a preferred embodiment, the present invention provides a safety scalpel that is improved over conventional scalpel tools, the safety scalpel comprising: reusable metal scalpel handles that resemble most surgeons' favorite conventional metal handles in shape and feel, and disposable blade cartridges that cover the blade before, during, and after use and that can be easily mounted to and released from the scalpel handle.

The safety scalpel of the present invention comprises: a blade having a cutting profile similar to a standard surgical blade, a blade holder secured to the blade, and a blade guard covering the blade and within which the blade holder can slide, a scalpel handle that receives a blade cartridge (the blade, blade holder, and blade guard are assembled together), and a locking assembly. The scalpel handle is reusable, while the blade cartridge is disposable.

Prior art designs have included disposable blade cartridges in which the blade guard slides away from the releasably secured blade, but the present invention is based on sliding the blade out of the releasably secured guard.

The present invention comprises a safe disposable blade cartridge that can be used with preferably reusable metal scalpel handles or disposable plastic scalpel handles, having the weight and feel of conventional designs. The blade cartridge is easily secured to the scalpel handle and can be securely and releasably locked thereto. The blade is preferably movable through at least three different positions-open, closed and locked.

Attaching and detaching the blade cartridge to and from the scalpel handle with an easy, longitudinal sliding motion. When secured to the scalpel handle, only the blade and blade holder of the blade cartridge can move in a longitudinal direction because the blade guard has limited or no longitudinal movement.

According to other preferred embodiments, the blade cartridge itself is a separate small scalpel that is securely fixed to a metal handle and is passive, or the blade is movable within a hollow metal holder.

According to other embodiments, the blade is immobilized against movement when the reusable handle is removed.

An operating and construction method is also provided herein.

For example, a safety scalpel is disclosed having a disposable blade cartridge with a blade, a blade holder in communication with the blade, and

a blade guard adapted to receive the blade and the blade holder; and a non-disposable scalpel handle having a distal end, wherein the disposable blade cartridge is slidable onto the distal end of the non-disposable scalpel handle, the disposable blade cartridge adapted to be lockable to the non-disposable scalpel handle.

The safety scalpel may further include a catch for engaging an extension, and the catch engaging the extension locks the disposable blade cartridge to the scalpel handle.

The safety scalpel may also include a blade holder having a holder knob, the blade being movable from a closed position in which the blade is not exposed from the disposable blade cartridge to an open position in which the blade is exposed from the disposable blade cartridge.

The safety scalpel may further include an extension member, the disposable blade cartridge including a catch for engaging the extension member, wherein the catch engaging the extension member locks the disposable blade cartridge to the scalpel handle, and the blade holder further includes a holder knob that enables the blade to move from a closed position in which the blade is not exposed outside the disposable blade cartridge to an open position in which the blade is exposed outside the disposable blade cartridge.

The scalpel may also include a latch assembly including a locking mechanism adapted to engage an aperture of the scalpel handle such that the latch assembly locks the blade cartridge to the scalpel handle.

Another embodiment of the scalpel may also include a mechanical brake that provides friction to prevent movement of the blade, the brake including at least one member that provides friction to prevent movement of the blade only when the handle is removed.

The scalpel may include a space for receiving the handle, and the detent member comprises a finger that flexibly projects into the space for use by the handle, the detent thereby being prevented from interfering with movement of the blade, the finger being configured to engage at least a portion of the blade holder when the handle is not in place, thereby preventing movement of the blade without the handle.

The scalpel may include a finger having a contact platform with a beveled surface proximate where the platform contacts the blade holder when engaged.

The scalpel may further comprise a locking safety of the safety catch for preventing accidental retraction of the blade when in use, comprising: a slider knob at least partially external to the blade guard and in mechanical communication with the blade such that movement of the slider causes movement of the blade, the slider including a base and a releasable engagement portion; a catch portion sized to receive the engagement portion, the catch being located on the guard such that the catch portion and engagement portion are engaged when the blade is in the fully extended position.

Additionally, the safety device may include a resilient portion extending from the base, the resilient portion having a free end and being spaced apart from the base. The resilient portion may be arcuate and depressible and include a catch at its free end, wherein the catch portion includes a receptacle sized to receive the catch, such that when the resilient portion is depressed, the catch may be engaged within the receptacle, thereby preventing movement of the blade.

The scope of the invention is determined by the claims, which are intended only to provide the reader with a preview of the remainder of the entire specification.

Drawings

FIG. 1A illustrates a perspective view of a safety scalpel according to a preferred embodiment of the present invention;

FIG. 1B illustrates a perspective view of a safety scalpel according to another preferred embodiment of the present invention;

FIG. 2A illustrates a perspective view of an unassembled blade and blade holder according to a preferred embodiment of the present invention;

FIG. 2B illustrates a perspective view of the assembled blade and blade holder of FIG. 2A;

FIG. 2C illustrates a perspective view of the front surface of the blade holder in accordance with a preferred embodiment of the present invention;

FIG. 2D illustrates a perspective view of the rear surface of the blade holder of FIG. 2C;

FIG. 3A illustrates a perspective view of the front surface of the blade guard in accordance with a preferred embodiment of the present invention;

FIG. 3B illustrates a perspective view of the rear surface of the blade guard of FIG. 3A;

FIG. 3C illustrates a perspective view of the front surface of the blade guard according to another preferred embodiment of the present invention;

FIG. 3D illustrates a perspective view of the rear surface of the blade guard of FIG. 3C;

FIG. 3E illustrates a perspective view of the proximal end of the blade guard of FIG. 3C;

FIG. 4 illustrates a perspective view of a cartridge assembly in accordance with a preferred embodiment of the present invention;

FIG. 5 illustrates a front, perspective view of a blade cartridge connected to a scalpel handle;

FIG. 6A illustrates a perspective view of the front surface of a safety scalpel having a blade housed in a blade cartridge in accordance with a preferred embodiment of the present invention;

FIG. 6B illustrates a perspective view of the front surface of the safety scalpel of FIG. 6A with a blade extending from the blade cartridge in accordance with a preferred embodiment of the present invention;

FIG. 6C illustrates a perspective view of the rear surface of the safety scalpel of FIG. 6A received in a blade cartridge in accordance with a preferred embodiment of the present invention;

FIG. 7 illustrates a close-up, front view of the distal end of a blade cartridge having blades extending from the blade guard in accordance with a preferred embodiment of the present invention;

FIG. 8 illustrates a perspective view of the rear surface of a safety scalpel similar to that of FIG. 5C except for a blade housed in a guard having an integrated mechanical stop in accordance with a preferred embodiment of the present invention;

FIG. 9 is a close-up partial perspective view of a portion of the view of FIG. 8, enlarged to show detail of the associated stop 1301;

FIG. 10 is a partial close-up view similar to FIG. 9, except on opposite sides; and

fig. 11 is a partial close-up view of a portion of another embodiment of a safety scalpel.

Detailed Description

Referring now in detail to the drawings in which like reference numerals refer to like parts throughout the several views, the safety scalpel 10 of FIGS. 1A, 1B and 6A-6C includes a blade 100 that is securable to a blade holder 200, the subassembly being slidable within a blade guard 300. The combination of the blade 100, the blade holder 200, and the blade guard 300 forms a blade cartridge 400 that can be connected to a scalpel handle 500.

The safety scalpel 10 of the present invention includes a blade cartridge 400 and a scalpel handle 500, the blade cartridge 400 being configured for secure attachment to the scalpel handle 500 and for safe detachment from the scalpel handle 500. In a preferred embodiment of the invention, the blade cartridge 400 is disposable, while the scalpel handle 500 is non-disposable. Thus, a new blade cartridge 400 can be attached to the scalpel handle 500 for use by, for example, a medical practitioner. After the medical practitioner has used the safety scalpel 10, the blade cartridge 400 can be safely removed from the scalpel handle 500 so that the blade cartridge 400 can be properly disposed of.

The blade cartridge 400 may include a blade 100, a blade holder 200 adapted to securely engage the blade 100, and a blade guard 300 configured to slidably receive the blade 100 and the blade holder 200. Also, the blade holder 200 is adapted to move the blade 100, or a portion thereof, between the closed position and the open position. In the closed position, the blade 100 is safely and completely contained within the blade guard 300. In the open position, the blade 100 or a portion thereof extends beyond the blade guard 300. With this design, the blade 100 is in the closed position during non-use of the safety scalpel 10 and is in the open position during effective use of the safety scalpel 10. Thus, the safety scalpel 10 of the present invention provides a safe and effective surgical tool.

As shown in fig. 2A and 2B, the blade 100 includes a cutting edge 110 at the distal end 102 of the blade 100. Also, the blade 100 defines an aperture 120 at the proximal end 107; preferably an elongated aperture 120 such as a slot. The blade 100 preferably has similar front and rear surfaces, except for the profile of the cutting edge 110.

One skilled in the art will recognize that the blade 100 can be made from a variety of suitable materials, including, but not limited to, carbon and stainless steel. Typically, the carbon and stainless steel used to form the blade 100 are manufactured according to different industry standards, including british standard ("BS") 2982: 1992. international organization for standardization ("ISO") 7740: 1985 and European Standard ("EN") 27740: 1992. the blade 100 may also be sterilized, for example, by gamma radiation.

The blade holder 200 is designed to mate with the blade 100. Unlike the blade 100, the front surface 210 and the rear/back surface 225 of the blade holder 200 are dissimilar and the thickness of the blade holder 200 is also not uniform. The distal end 202 of the blade holder 200 includes a holder protrusion 205 that extends from the front surface 210 of the blade holder 200 in a profile that substantially corresponds to the aperture 120 of the blade 100. The holder protrusion 205 is adapted to be securely engaged in the aperture 120 of the insert 100.

The blade holder 220 may further include a protruding stop 215 on the proximal end of the holder protrusion 205 such that the protruding stop 215 locks the blade 100 to the blade holder 200. When the holder protrusion 205 engages the blade aperture 120, the blade 100 preferably snaps into the protrusion stop 215, thereby preventing the blade 100 from being accidentally disengaged from the blade holder 200.

The blade holder 200 further includes a holder knob 220 extending from the front surface 210 of the blade holder 200 at the proximal end 207. The surface of the holder knob 220 may include a plurality of ridges 222 for increasing traction when in contact with a finger during use of the safety scalpel 10. As described more fully below, the holder knob 220 is adapted to move the blade 100 between the closed and open positions when in communication with the blade guard 300.

The rear surface 225 (see fig. 2D) of the blade holder 200 can include a track 240 for receiving the scalpel handle 500, preferably the blade receiving portion 550 of the scalpel handle 500. The track 240 limits lateral movement of the blade cartridge 400 when secured to the scalpel handle 500.

As shown in fig. 3A-3E and 4, the blade guard 300 is designed to slidably receive the blade 100 and the blade holder 200. When the blade 100 is in the closed position, the blade guard or blade sheath 300 sufficiently surrounds the blade 100 so that the blade 100 cannot inadvertently cut, puncture, or otherwise damage material or an individual.

There are at least two preferred embodiments of the blade guard 300. The first embodiment is shown in fig. 3A-3B, while the second embodiment is shown in fig. 3C-3E. The embodiment chosen depends on the type of scalpel handle 500 used.

The blade guard 300 includes an aperture 320 (also referred to herein as a slot 320) for providing a track for the holder knob 220 of the blade holder 200 to slide between the closed and open positions. Accordingly, as the holder knob 220 moves between the retracted position and the forward position, the blades 100 move between the closed position and the open position, respectively. More specifically, the directional force applied to the holder knob 220 of the blade holder 200 allows the holder knob 220 to slide along the slot 320 when moving the blade 100 and the blade holder 200 between the closed position and the open position.

The blade guard 300 defines a cavity 305 therein. The blade 100 and blade holder 200 are positioned within the cavity 305 for sliding movement as the holder knob 220 slides within the slot 320. The holder knob 220 is positioned proximate the proximal end 327 of the slot 320 when the blade 100 is in the closed position, and the holder knob 220 is positioned proximate the distal end 322 of the slot 320 when the blade 100 is in the open position.

The blade guard 300 includes a front catch 325 and a rear catch 330, the front catch 325 being positioned proximate the distal end 322 of the slot 320 and the rear catch 330 being positioned proximate the proximal end 327 of the slot 320. The front catch 325 is adapted to engage the holder knob 220 when the blade 100 is in the open position. The front catch 325 prevents the blade holder 200 from moving forward beyond the open position. The front catch 325 can include a flexible lock 326 that locks the blade holder 200 to prevent the blade 100 from being opened in the open position by mistake. Similarly, the rear catch 330 is adapted to engage the holder knob 220 when the blade 100 is in the closed position. The rear catch 330 may prevent the blade holder 200 from moving rearward beyond the closed position. Alternatively, the rear catch 330 prevents the blade holder 200 from moving the blade 100 rearwardly beyond the fully locked position. Also, the rear catch 330 may prevent accidental opening of the blade holder 200, thereby attempting to prevent accidents.

The blade guard 300 may include a plurality of slots 340 positioned on the rear surface 315 of the blade guard 300, as shown in fig. 3B and 3D. The plurality of grooves 340 may prevent slippage of the safety scalpel 10 during use.

The blade guard has a front surface 310 as shown in fig. 3A and 3C and a back/back surface 315 as shown in fig. 3B, 3D, and 3E. The front face 310 of both embodiments is preferably identical. However, the back surface 315 may have different properties.

Advantageous features of the different rear surfaces 315 include a method of releasing the blade guard 300, and thus the blade cartridge 400, from the scalpel handle 500.

The blade guard 300 of fig. 3C and 3D further includes a latch assembly 345 for releasing the blade guard 300 from the scalpel handle 500. The lockout assembly 345 includes a knob 350 extending from the rear surface 315 of the blade guard 300, and a locking mechanism 355. The surface of the knob 350 may include ridges 352 for increasing traction when in contact with a finger during removal of the blade guard from the scalpel handle 500. As described more fully below, the knob 350 is adapted to remove the blade cartridge 400 from the scalpel handle 500.

Those skilled in the art will recognize that the blade holder 200 and blade guard 300 may be made from a variety of suitable materials, including but not limited to plastics, such as Acrylonitrile Butadiene Styrene (ABS) copolymer plastics.

As described above, the blade 100 and the blade holder 200 are assembled in the blade guard 300. These three components collectively form the blade cartridge 400. The blade cartridge 400 can be attached to and detached from the distal end of the scalpel handle 500.

The scalpel handle 500 shown in fig. 1A and 1B includes a handle portion 540 and a blade receiving portion 550. The handle portion 540 extends from an approximate midpoint 555 of the scalpel handle 500 to the proximal end 507 of the scalpel handle 500, while the blade receiving portion 550 extends from the approximate midpoint 555 to the distal end 502 of the scalpel handle 500.

The distal end 502 of the scalpel handle 500 can be cut on the front surface 510 to accommodate the blade cartridge 400. Preferably, the distal end 502 of the scalpel handle 500 can have a tapered portion 504 for improved assembly of the safety scalpel 10.

The scalpel handle 500 includes at least one extension 530 located on the front surface 510 of the proximal end 557 of the blade receiving portion 550, such as near the approximate midpoint 555. The extension member 530 extends outwardly from the scalpel handle 500 and is adapted to enable the blade cartridge 400 and the scalpel handle 500 to be secured.

That is, the at least one extension or intermediate stop 530 is adapted to engage at least one catch 335 of the blade cartridge 400 (e.g., the catch 335 of the blade guard 300). When the blade cartridge 400 is connected to the scalpel handle 500, the catch 335 of the blade cartridge 400 can engage the extending member 530 or snap around the extending member 530 to prevent longitudinal movement of the blade cartridge 400. In addition, lateral movement of the blade cartridge 400 is limited due to the form-fitting blade receiving portion 550.

To increase the traction of the scalpel handle 500 when in contact with a finger during use of the safety scalpel 10, the handle portion 550 can include a plurality of grooves 525 positioned on the rear surface 515 of the scalpel handle 500, as shown in FIG. 6C. The plurality of grooves 525 may prevent slippage of the safety scalpel 10 during use.

As shown in fig. 1A, 1B, 6A, and 6B, the handle portion 550 of the scalpel handle 500 can include indicia 520. The markings 520 are generally located on the front surface 510 of the scalpel handle 500 proximate the proximal end 507. While one skilled in the art will recognize that the indicia 520 of the present invention may include a plurality of indicia or printed words, the indicia 520 is preferably a unit of measure such as, but not limited to, the metric system, the imperial system, or many other suitable measuring systems.

The scalpel handle 500 is designed to receive the blade cartridge 400 and provide the user with the feel of a conventional scalpel when in use. Thus providing a material, weight and design suitable for comfortable use by the user.

Assembly of the blade cartridge 400

The blade cartridge 400 includes the assembled mating blade 100, blade holder 200, and blade guard 300 as shown in fig. 4. Preferably, the blade cartridge 400 is assembled outside of the site of ultimate use of the safety scalpel 10 as shown, e.g., a factory, so that only the assembled blade cartridge 400 is shipped to the user. Further, the blade 100 may be attached to the blade holder 200 by insert molding, wherein the blade holder 200 is actually formed and molded around the blade 100. By using insert molding, the blade 100 does not have to be subsequently attached to the blade holder 200.

The blade cartridge 400 may be shipped in its own sterile packaging, such as an aluminum foil package. Thus, the blade cartridge 400 is not assembled by the user, but rather the blade cartridge 400 is mated with the scalpel handle 500.

As described above, the blade 100 is secured to the blade holder 200 by aligning the blade aperture 120 with the corresponding holder protrusion 205 of the blade holder 200. The protruding shelf 215 allows the blade 100 to be secured to the blade holder 200 as shown in fig. 2A and 2B.

The blade holder 200 with the blade 100 is then attached to the blade guard 300 by sliding and placing the blade holder 200 in the aperture 305 of the blade guard 300. This is indicated by the arrows in fig. 4.

To connect the blade 100 and the blade holder 200 into the blade guard 300, the blade 100 and the blade holder 200 are inserted into the blade guard 300 to align the blade 100 in a cavity 305 defined by lateral sides of the blade guard 300 and to fit the holder knob 220 in the slot 320. As shown in fig. 4 (see arrow), the blade holder 200 is placed in the blade guard 300 such that the stop rib 230 on the blade holder 200 engages the rear retaining groove 370 of the blade guard 300.

The blade holder 200 and blade 100 are temporarily locked in the blade guard 300 by the holder stop rib 230 engaging and locking with a mating rear retention groove 370 on the blade guard 300. Thus, the blade 100 may be held in the locked position.

In the assembled blade cartridge 400, the blade 100 is entirely enclosed in the blade guard 300 before being mounted to the scalpel handle 500 for use.

Mounting of the blade cartridge 400 to the scalpel handle 500

As shown in fig. 1A and 1B, the process of mounting the assembled blade cartridge 400 to the scalpel handle 500 is relatively simple. The distal end 502 of the scalpel handle 500, i.e., the blade receiving portion 550, is preferably inserted into the cavity 305 of the blade cartridge 400 at the proximal end 307. In practice, the blade receiving portion 550 of the scalpel handle 500 can be received in the track 240 of the rear surface 225 of the blade holder 200, thereby securing the blade cartridge 400 to the scalpel handle 500. The blade cartridge 400 is slid to a position where the catch 335 engages the extension member 530.

The catch 335 of the blade cartridge 400 is configured to latch around the extending member 530. Also, the proximal end 307 of the blade cartridge 400 (e.g., the proximal end 307 of the blade guard 300) is adapted to abut the approximate midpoint 555 of the scalpel handle 500 such that the blade cartridge 400 has limited or no longitudinal and/or lateral movement. Fig. 5 illustrates the closing of the blade cartridge 400 secured to the scalpel handle 500 such that the catch 335 is latched to the extending member 530.

Additionally, when the scalpel handle 500 includes the aperture 505, the blade cartridge 400 can be further secured to the scalpel handle 500. The blade cartridge 400 (e.g., the blade guard 300) may include a latch assembly 345. The lockout assembly 345 includes a locking mechanism 355 that engages the aperture 505 of the rear surface of the scalpel handle 500. This engagement further secures the blade cartridge 400 to the scalpel handle 500.

Use of the safety scalpel 10

When first installed, the blades 100 in the blade cartridge 400 are in a closed position, as shown in fig. 6A and 6C. By depressing the holder knob 220 of the blade holder 200 (e.g., pushing the holder knob 220 downward) or alternatively simply pushing the distal end 202 of the blade holder 200 outward, the stop rib 230 on the blade holder 200 is released from the rear retaining slot 270 on the blade guard 300, the holder knob 220 is slid along the slot 320 of the blade guard 300 until the blade 100 reaches the open position so that the blade 100 can extend out of the blade guard 300, after which the holder knob 220 is released so that the stop rib 230 on the blade holder 200 engages the front retaining slot 375 on the blade guard 300. Thus, the blade 100 is temporarily locked in the open position. When the blade guard 300 engages the front retention slot 375, the flexible lock 326 may be moved outward toward the edge of the blade guard 300 to lock it.

In this open position, as shown in fig. 6B, the safety scalpel 10 is ready for use, i.e., cutting and/or slicing. Also, in this position, the blade 100 is prevented from lateral and transverse movement during use of the safety scalpel 10.

The blade cartridge 400 (e.g., the blade guard 300) may further include a plurality of notches 380, as shown in fig. 1A, 3A, and 3B. The plurality of notches 380 are positioned on at least one side/lateral edge of the blade guard 300 such that the plurality of notches 380 provide increased gripping force on the safety scalpel 10 during use.

If the user desires to hand the safety scalpel 10 to a colleague, the user first moves the blade 100 to the closed position by depressing the holder knob 220 on the blade holder 200 to release the stop rib 230 from the front retaining groove 375. Alternatively, the user may move the holder knob 220 toward the proximal end 307 of the blade guard 300. In either case, this slides the holder knob 220 back along the slot 320 of the blade guard 300 until the blade 100 reaches the closed position, after which the holder knob 220 is released to allow the stop rib 230 on the blade holder 200 to re-engage the rear retaining slot 370 on the blade guard 300. The blade 100 is now temporarily locked in the closed position. The blade 100 may be moved between the open and closed positions any number of times until the procedure is complete.

Detaching the blade cartridge 400 from the scalpel handle 500

Since at least two embodiments of the scalpel handle 500 can use two different blade guards 300, there are also two different procedures for detaching the blade cartridge 400 (e.g., the blade guard 300) from the safety handle 500.

In a first embodiment, the blade guard 300 of fig. 3A and 3B is secured to the scalpel handle 500 of fig. 1A, i.e., without the aperture 505 (see fig. 1B).

The blade guard 300 in this first embodiment is removed by placing the holder knob 220 in the rear retention slot 370 such that the blade 100 is in the closed position and does not extend from the blade guard 300. The holder knob 220 may slide slightly further toward the proximal end 307 of the blade cartridge 400 (e.g., the proximal end 307 of the blade guard 300) or toward the approximate midpoint 555. When the holder knob 220 is slid in this direction, the catch 335 moves away from the extending member 530 of the scalpel handle 500. This may release the blade cartridge 400 from the scalpel handle 500. The user then simply slides the entire blade cartridge 400 toward the distal end 502 of the scalpel handle 500, or away from the scalpel handle 500.

In the second embodiment, the scalpel handle 500 includes an aperture 505 proximate the extension 530, preferably offset slightly toward the distal end 502. In this embodiment, the blade cartridge 400 (e.g., the blade guard 300) further includes a locking mechanism 355 around the rear surface 315 thereof.

Once the locking mechanism 355 is removed from the aperture 505, the catch 335 may be released from the extension 530, as described above. The blade cartridge 400 is then loose enough to be released from the scalpel handle 500. In essence, the latch assembly 345 is an additional safety feature that helps ensure that the blade cartridge 400 does not mistakenly release from the scalpel handle.

The rear surface 315 of the blade cartridge 400 (e.g., the rear surface 315 of the blade guard 300) mates with the rear surface 515 of the scalpel handle 500. The latch assembly 345 is adapted to engage the aperture 505 of the scalpel handle 500 when the blade cartridge 400 is secured to the scalpel handle 500. The lockout assembly 345 includes a knob 350 and a locking mechanism 355. Because the locking mechanism is an inwardly extending mechanism, the locking mechanism engages the hole 505 in its normal state. However, if the knob 350 is depressed, the locking mechanism 355 disengages from the aperture 505. Knob 350 may include a plurality of ridges for increasing traction when locking mechanism 355 is removed from aperture 505.

Disposable safety scalpel 10

In another alternative embodiment of the present invention, the safety scalpel 10 includes a disposable scalpel handle 500, such that the disposable scalpel handle 500 is separate from the blade cartridge 400 and is passive. The disposable scalpel handle 500 is adapted to be attached to the blade cartridge 400. Preferably, the blade cartridge 400 and the disposable scalpel handle 500 are permanently secured to each other in the factory during the manufacturing process of the safety scalpel 10. After use, the blade cartridge 400 and disposable scalpel handle 500 can be properly disposed of.

Alternative preferred embodiment

To further enhance the safety of the scalpel, the preferred embodiment of fig. 8-10 discloses additional means to ensure that the blade does not move accidentally, even when the user is attempting to operate the device incorrectly. In describing this embodiment, to the extent it is consistent with the previous embodiments, the same reference numerals are used, and reference should first be made to the previously described drawings. In this embodiment of the invention, the safety scalpel 10 includes a non-disposable scalpel handle 500, such that the non-disposable scalpel handle 500 is separate from the disposable blade cartridge 400 and is passive. The non-disposable scalpel handle 500 is adapted to be connected to the disposable blade cartridge 400. In this embodiment, it is preferred to ensure, for safety, that when the lockout assembly 345 is disengaged from the catch 355, the surgical blade 100 remains securely contained within the guard 300 and the entire blade guard 300 is discarded.

Fig. 8 illustrates a perspective view of the rear surface of the safety scalpel 10 with the blade 100 (not shown) entirely contained within the blade guard 1300, in accordance with a preferred embodiment of the present invention. Components in fig. 8 that directly correspond to components in fig. 1A have the prefix "1" added (i.e., 1000 added). The blade guard 1300 may be made of a plastic-like material, and an area of the blade guard 1300 may be configured to protrude into an interior area of the blade guard 1300. The protrusion in the interior region of the blade guard 1300 will be referred to hereinafter as a mechanical stop or detent 1301. Fig. 8 shows the mechanical stop 1301 located near the edge of the rear surface of the blade guard 1300. The mechanical stop 1301 may protrude inwardly into the space designated for the scalpel to pass through. The stop/guard mechanically secures the surgical blade 100 within the blade guard 300 when the blade guard is removed from the handle 500, either directly or by engaging with the blade holder 200. This is achieved by creating a frictional contact (i.e., biasing force) between the stop 1301 and the holder 200 (or blade 100). In practice, the stop 1301 is a finger that protrudes into the space to be occupied by the holder 200, thereby exerting a frictional resistance thereon. This resistance can preferably be easily overcome by inserting the handle 500, which lifts the projection of the detent 1301 out of the area. In a preferred construction, the stop 1301 will be "deactivated" when the handle is inserted.

The stop 1301 can be constructed in a variety of ways and can be positioned in a number of places. The preferred position is shown in figure 10. In this embodiment, there are a pair of stops 1301 formed as fingers 1301a in the plastic guard, cut from the guard material itself and biased into the path of travel of the surgical blade.

The finger is actually two parts. See fig. 9-10. A first portion 1301e extends from and is resiliently connected to the plastic housing and a second portion 1301c extends at the distal, platform into the space for the sliding blade. The platform is preferably a chamfer 1301d (rounded or beveled edge) to prevent the blade from getting trapped (halted) when engaging the blade holder 200 and also to increase the force per unit area at the contact site.

There are other ways to achieve this important braking action. First, only one stop may be used. It may also be provided on the side wall instead of the bottom or top as shown. The braking action itself may be achieved by friction pads affixed within the safety housing, or by magnets embedded in the housing to create a reluctance force against the steel blade (unless non-magnetic stainless steel is used). The scope of the present invention includes other mechanical means for preventing inadvertent movement of the blade when the lock is released.

The degree of bias and resiliency of the fingers should be such that the blade cannot move without being pushed by the user, but insertion of the handle 500 is not impeded by the resistance created by the stop 1301. In practice, the tool shank, when inserted, can easily lift the stop out of the way, in part due to the chamfered edge on finger 1301 d.

In one embodiment of the present invention, the mechanism by which the mechanical stop 1301 secures the scalpel blade 100 within the blade guard 1300 during its disposal is described below.

In preparation for disposal of the blade guard 1300, the surgeon may first retract the surgical blade completely within the blade guard 1300. The surgeon may then begin to separate the non-disposable scalpel handle 1500 from within the blade guard 1300 by applying a force to the latch assembly 1345 in a direction toward the distal end 1302 of the blade guard 1300. When the distal end 502 (see fig. 1, item 502) of the non-disposable scalpel handle 1500 passes under the mechanical stop 1301, the mechanical stop may now mechanically engage the stop 1301 and possibly the distal ends of the ridges 223a and 223b (see fig. 2C, 2D) of the blade holder 200 and secure the scalpel blade 100 within the blade guard assembly 1300. During normal surgical use of the safety scalpel 10, when a non-disposable scalpel handle 1500 is inserted into the blade guard 1300 (with the enclosed scalpel blade 100), the distal end 502 of the handle (see fig. 1A) slides along the top surface of ridges 223a and 223b (see fig. 2C, 2D) of the blade holder 200 until the distal end 502 of the handle first engages the mechanical stop 1301. In one embodiment of the invention, the mechanical stop may be deformable and the top surface of the scalpel surface may apply sufficient force to deform the mechanical stop flush with the surface of the blade guard 1300, thereby inserting the scalpel handle between the mechanical stop 1301 and the ridge of the blade holder 200, allowing the scalpel blade to move freely within the blade guard 1300 by applying force to the holder knob 220 (see fig. 1A). In a preferred embodiment of the present invention, the mechanical stop 1301 may be positioned proximate to the slot 1340 in fig. 8, in which position the mechanical stop 1301 may engage the distal ends of the ridges 223a and 223b (see fig. 2C and 2D) at the location where the surgical blade 100 abuts the proximal end 207 (see fig. 1A) of the blade holder, thereby ensuring that the surgical blade 100 is fully and safely contained within the blade guard 1300.

Those skilled in the art will recognize that the disposable scalpel handle 500 can be made from a variety of materials, including but not limited to plastics, such as Acrylonitrile Butadiene Styrene (ABS) copolymer plastic.

In yet another alternative embodiment of the present invention, the safety scalpel 10 includes a disposable scalpel handle 500 having a slidable blade 100 and blade holder 200 received therein. Thus, the blade guard 300 is an integral part of the disposable scalpel handle 500, and thus, the blade guard 300 is not separated from the scalpel handle 500. Also, the entire safety scalpel 10 is disposable after use.

The blade cartridge 400 and scalpel handle 500 are attached and detached as described above.

Those skilled in the art will recognize that the scalpel handle 500 (e.g., the entire safety scalpel 10, the removal blade 100) can be made from a variety of materials, including but not limited to plastics, such as Acrylonitrile Butadiene Styrene (ABS) copolymer plastic.

FIG. 11 illustrates another safety feature as an alternative to the knob slider 220 in FIG. 1A.

Generally, there should be a safety catch to prevent accidental retraction of the blade when in use, the safety catch having: a slider at least partially external to the blade guard and in mechanical communication with the blade such that movement of the slider causes movement of the blade, the slider including a base portion and a releasable engagement portion; and a catch portion sized to receive the engagement portion, the catch being located on the guard such that the catch and engagement portion are engaged when the blade is in the fully extended position.

Additionally, the safety may include a resilient portion extending from the base, having a free end and being spaced apart from the base. The resilient portion may be arcuate and depressible and include a catch at its free end, wherein the catch portion includes a receptacle sized to receive the catch, such that when the resilient portion is depressed, the catch may be engaged within the receptacle, thereby preventing movement of the blade.

In place of slider knob 220 is a compressible slider 2220 that provides a means for the user to extend or retract the blade. Fig. 11 shows the blade in the fully extended position. In addition to the other devices provided herein, the slider 2220 provides an additional locking device for preventing accidental retraction of the blade. The slider 2220 may include ridges 2222 that provide a good frictional gripping force. Extending from the base of the blade is a resilient ring 2224 which is preferably attached at one end of the base of the slider and free at the other end. The free end includes a hook-like structure 2226 in the form of a one-way fishhook or simply a platform extending radially away from the free end loop 2224, e.g., a right angle platform extending perpendicularly from the base of the free end to form a flat surface. Distal to the platform, the surface may be chamfered or rounded to allow the platform to slide under the bridge with less resistance.

The loop 2224 is preferably formed in an arcuate shape or at least spaced from the base 2230 of the slider. This provides clearance for the elastomeric ring to flex therein. By applying pressure to the loop, the hook/fishhook is depressed and will easily slide under gate 2228, which gate 2228 is a receiving channel or bridge for receiving the hook/fishhook. When pressure is released from the loop, the loop returns to its alternative state position in which the fish hook 2226 engages the side wall of the bridge 2228 to prevent retraction of the blade until the user depresses the loop 2224 further to release the hook 2226 from the gate 2228 sufficiently to retract the hook back out of the gate.

In this way, a further safety feature may be included in the scalpel to prevent inadvertent retraction of the blade when in use, but to provide for convenient retraction when required.

Although the present invention has been disclosed in its preferred forms, it will be apparent to those skilled in the art that various modifications, additions and deletions can be made therein without departing from the spirit and scope of the invention as set forth in the following claims and their equivalents.

Claims (18)

1. A safety scalpel, comprising: disposable blade cassettes and non-disposable scalpel handles,

the disposable blade cartridge including a blade and a blade holder holding the blade, the blade cartridge further including a blade guard adapted to receive the blade and the blade holder,

wherein a track in a rear surface of the blade holder is configured to slidably receive and accommodate a blade receiving portion of the scalpel handle, the rear surface of the blade holder being opposite the surface of the blade holder that holds the blade, and

wherein the blade cartridge is configured to lock onto the scalpel handle.

2. The safety scalpel of claim 1, wherein the non-disposable scalpel handle comprises an extension, wherein the disposable blade cartridge comprises a catch for engaging the extension, and the catch engaging the extension locks the disposable blade cartridge to the scalpel handle.

3. The safety scalpel of claim 1, wherein the blade holder further comprises a holder knob adapted to move the blade from a closed position in which the blade is not exposed outside the disposable blade cartridge to an open position in which the blade is exposed outside the disposable blade cartridge.

4. The safety scalpel of claim 1, wherein the non-disposable scalpel handle comprises an extension piece, wherein the disposable blade cartridge comprises a catch for engaging the extension piece,

wherein the catch engaging the extension locks the disposable blade cartridge to the scalpel handle, and

wherein the blade holder further comprises a holder knob capable of moving the blade from a closed position in which the blade is not exposed outside the disposable blade cartridge to an open position in which the blade is exposed outside the disposable blade cartridge.

5. The safety scalpel of claim 1, wherein the disposable blade cartridge further comprises a latch assembly comprising a locking mechanism adapted to engage an aperture of the scalpel handle such that the latch assembly locks the blade cartridge to the scalpel handle.

6. A safety scalpel as defined in claim 1 wherein said blade cartridge includes a mechanical stop to provide friction to prevent movement of said blade.

7. The safety scalpel of claim 6, wherein the brake comprises at least one member that provides friction preventing movement of the blade only when the handle is removed.

8. A safety scalpel as defined in claim 7 wherein said cartridge includes a space for receiving said handle and said detent member includes a finger that flexibly projects into said space for use by said handle so that said detent interferes with movement of said blade.

9. The safety scalpel of claim 8, wherein the finger is configured to engage at least a portion of the blade holder when the handle is not in place, thereby preventing movement of the blade without the handle.

10. The safety scalpel of claim 8, wherein the finger includes a contact platform having a beveled surface that prevents the blade from becoming trapped when the platform is engaged with the blade holder.

11. A safety scalpel as defined in claim 6 further comprising a safety catch for preventing accidental retraction of the blade in use comprising:

a. a slider knob at least partially external to the blade guard and in mechanical communication with the blade such that movement of the slider knob causes movement of the blade;

b. the slider knob includes a base and a releasable engagement portion;

c. a catch portion sized to receive the engagement portion, the catch portion being located on the guard such that the catch portion and the engagement portion are engaged when the blade is in the fully extended position.

12. A safety scalpel as defined in claim 11 wherein said engagement portion includes a resilient portion extending from said base, said resilient portion having a free end and being spaced from said base.

13. A safety scalpel as defined in claim 12 wherein said resilient portion is arcuate and depressible and includes a further catch at its free end, wherein said catch portion includes a receiving portion dimensioned to receive said further catch such that when said resilient portion is not depressed said further catch can be engaged within said receiving portion to prevent movement of said blade.

14. A method of connecting a disposable blade cartridge to a non-disposable scalpel handle, the disposable blade cartridge comprising a blade and a blade holder that holds the blade, the blade cartridge further comprising a blade guard adapted to receive the blade and the blade holder, the method comprising:

sliding and receiving a blade receiving portion of the scalpel handle in a track in a rear surface of the blade holder, the rear surface of the blade holder being opposite the surface of the blade holder that holds the blade;

locking the blade cartridge to the scalpel handle.

15. The method of claim 14, wherein the catch of the blade cartridge engages an extension of the scalpel handle.

16. The method of claim 15, wherein a latch assembly engages an aperture of the scalpel handle.

17. The method of claim 15, further comprising the steps of: movement of the blade within the cartridge is prevented except when the tool shank is partially received within the cartridge in place.

18. The method of claim 14, further comprising the steps of: frictional forces are applied to prevent movement of the blade and to remove the forces when the handle is inserted within the cartridge.