FIELD OF THE INVENTION

[0001] This invention relates generally to a protective cover for the probe of a medical instrument that is insertable into a body cavity.

BACKGROUND OF THE INVENTION

[0002] Many types of medical instruments, such as an infrared (IR) thermometer, contain a probe for insertion into a body cavity so that various body related measurements can be taken. In order to prevent cross contamination between patients or health care workers and patients, the probe is generally enclosed within a protective cover which can be disposed of in a sanitary manner after it has been used. Typically, this cover is manufactured from plastic using different types of molding techniques, many of which produce products that have surface imperfections or which can not be held to tight tolerances. Most protective covers are packaged and shipped with the covers being stacked one inside the other. Unstacking irregular formed covers and placing them upon the tip of an instrument can be extremely difficult. Defective covers tend to bind in the stack and as a consequence can be damaged and dropped during removal from the stack. Displacement or a misshapened cover from the instrument tip during an examination can also be unnerving to both the attending health care individuals and the patient. Lastly, an irregularly formed cover can hang up on the instrument during removal thus requiring unwanted manual handling of a potentially contaminated product. SUMMARY OF THE INVENTION

[0003] It is therefore a primary object of this invention to improve disposable probe covers that are suitable for use in the protection of insertion tips of medical instruments.

[0004] Another object of the invention is to provide for easy removal of a protective probe cover from a supply stack of probe covers.

[0005] A further object of the invention is to more positively secure a protective probe cover to a medical instrument to insure that the cover does not become prematurely dislodged during a patient examination.

[0006] A still further object of the present invention is to allow for the free release of a used probe cover from a medical instrument.

[0007] Yet another object of the present invention is to minimize the amount of manual handling that is required when loading and unloading a protective probe cover from a medical instrument.

[0008] Still another object of the present invention is to minimize the risk of damaging a protective probe cover as the cover is being loaded upon a medical instrument.

[0009] These and other objects of the invention are attained by a removable protective cover for a medical instrument that contains a probe that is suitable for insertion into a body cavity. The cover contains a flexible tubular body that compliments the tip geometry and a radially disposed flange that surrounds the proximal end of the body. A series of snap-on fasteners removably connect the cover to the instrument. A camming surface is located on the outer face of the flange which coacts with a cam follower that is movably mounted upon the instrument to flex the cover sufficiently to open the fastener and release the cover from the instrument. Alignment tabs are further provided on the flange that mate with openings in the instrument to properly register the cover with regard to the instrument.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] For a better understanding of these and other objects of the invention, reference will be made to the following detailed description of the invention which is to be read in association with the accompanying drawings, wherein:

[0011] Fig. 1 is a partial view in perspective illustrating the probe end of a medical instrument showing a protective cover embodying the invention securely affixed to the instrument;

[0012] Fig. 2 is a perspective view similar to that illustrated in Fig 1. showing the protective cover moved to a release position;

[0013] Fig. 3 is a further perspective view of the probe end of an IR thermometer with portions broken away to show the apparatus of the invention in greater detail;

[0014] Fig. 4 is a prospective view of the tip end of probe for use in a medical instrument embodying the present invention with the protective cover removed;

[0015] Fig. 5 is a prospective view similar to that illustrated in Fig. 4 showing a protective cover mounted upon the probe tip in an unsecured condition;

[0016] Fig. 6 is a prospective view similar to that shown in Fig. 5 with the cover secured to the tip of the instrument probe;

[0017] Fig. 7A is a partial view in section showing the probe tip of a medical instrument with a protective cover secured to the instrument in a locked position; [0018] Fig. 7B is an enlarged partial view showing in greater detail one of the snap- on fasteners in a locked position, as well as the cover ejector mechanism; [0019] Fig. 8 is a view similar to Fig. 7 A showing the ejector mechanism moved to a releasing position;

[0020] Fig. 9A is a partial view similar to that shown in Fig. 7 A showing a second embodiment of the invention with one of the fasteners in a locked position; [0021] Fig. 9B is an enlarged view showing the snap-on fastener and the ejector mechanism shown in Fig. 9A in greater detail; and

[0022] Fig. 10 is an enlarged view illustrating a number of protective covers stacked one inside the other.

DESCRIPTION OF THE INVENTION

[0023] Referring initially to Figs. 1-3, the present invention involving a protective probe cover generally referenced 10 that will be described herein with regard to an infrared thermometer 1 1. It should be clear to one skilled in the art, however, that the present invention can be used in conjunction with various other medical instruments having an extended probe for insertion into a body cavity. As pointed out above, disposable protective covers are placed over the probes to mitigate the danger of cross contamination occurring during and after an examination. The covers found in the prior art are typically made of plastic and are fabricated using various molding processes. Many of these molding methods, however, create imperfections in the final product and are unable to hold the product to close tolerances, thereby resulting in unwanted and potentially dangerous problems arising particularly during a medical procedure. [0024] Testing has shown that probe covers that are fabricated by an injection molding process can be held to tight tolerances while still having a desired amount of flexibility that help overcome many fabrication problems. Accordingly, any references made herein involving a protective probe cover embodying the present invention will be specifically directed to a plastic cover that has been injection molded. [0025] Figs. 1-3 illustrate the top section of a hand-held IR thermometer. This instrument includes a lower body section 12 and an upper head section or instrument head 13 that contains an insertion probe 10 that protrudes outwardly some distance from the head section of the instrument. As best illustrated in Fig. 3, the proximal end section 15 of the probe 10 is cylindrical in form and is secured by any suitable means to the head section 13. The distal end 16 of the probe 10 projects outwardly from the head section 13 and is conically shaped so as to taper downwardly from the cylindrical body of the probe towards the distal end tip 17. An IR sensor 18 is mounted in the tip of the probe 10. Although not shown, the sensor is connected by electrical leads to a processor that is located within the body of the instrument, which provides an accurate temperature read out to the user.

[0026] The probe cover 10 is shown in Figs. 1 and 3 mounted upon the extended end of the probe 10 in a locked position wherein the cover is securely fastened to the probe. The inner wall surface 32 of the cover complements the conical wall surface of the probe. As will be explained in further detail below, the cover is releasably secured to the probe by a series of snap-on fasteners 50. As best illustrated in Fig. 3, an ejector mechanism, generally referenced 25 is slidably mounted inside the instrument head 13 upon the cylindrical section of the probe 10. The ejector mechanism is equipped with a circular ring 24 that surrounds the cylindrical section of the probe 10 to provide a close running fit there between so that the ejector can be moved axially along the centerline 29 of the probe between a first cover locking position and a second cover releasing position. [0027] The ring of the ejector contains a raised finger engagable control button 26 that passes upwardly through an opening 27 contained in the head of the instrument. When the control button is situated at the back of the opening as shown in Fig. 1, the ejector mechanism is in the first probe locking position. Manual movement of the control button to the front of the opening, as illustrated in Fig. 2, places the ejector mechanism at a second probe releasing position.

[0028] Turning now to Figs. 4-6 there is illustrated the front circular shoulder mount 30 of the probe assembly, which is retained within the front wall 31 of the instrument head 13 to support the distal end 16 of the probe in assembly. Fig. 4 shows a probe without a cover. Two opposed arcuate shaped slots 33-33 are located in the probe mount 30 that are centered upon the longitudinal axis 29 of the probe. A pair of arcuate shaped fingers 35-35 are integrally joined to the ejector ring 24 and are slidably contained within the slots 33-33. The fingers 35-35 are arranged to be extended and retracted as the ejector moves between the first and second positions. A series of circumferentially spaced segmented detent bead segments 38-38 are mounted upon the probe and, as will be explained in greater detail below, each bead section is the male part of a two part snap- on fitting for releasably securing the probe cover 10 to the instrument. Preferably three equally spaced fittings are employed to secure the cover to the instruments, however, more or less fittings may be employed depending upon the particular application. [0029] Fig. 5 illustrates a protective cover 10 mounted in a locked position upon the probe. At this time, the flange 40 of the cover has engaged the fingers 35-35 of the ejector mechanism and has moved the ejector back to the cover locking position due to the rearward movement of the cover over the probe. Full rearward movement is attained when the snap-on fasteners engage the bead segments on the probe. [0030] Fig, 6 illustrates a probe cover located upon the probe with the ejector mechanism in the cover releasing position. At this time the control button 25 (Fig. 3) has been moved forward, causing the ejector mechanism to unlock the fasteners thus releasing the cover. In addition the continued movement of the ejector toward the distal end of the probe frees the cover from the probe.

[0031] Figs. 7 A, 7B and 8 illustrate a first embodiment of the invention detailing apparatus for securing and releasing a probe cover from the instrument. Fig 7A shows the above described ejector mechanism 25 moved back into the first cover locking position and a snap-on fastener generally referenced 50 in a cover securing condition. At this time, the cover is snuggly contained upon the probe. The cover contains an IR transparent lens or window 19 mounted in the distal tip thereof, which is now located in close proximity with the IR sensor 18 (see Fig. 3).

[0032] With further reference to Fig. 7B, the securing and releasing apparatus is shown in further detail in the locked position. Each snap-on fastener 50 includes two mating parts or sections. These include the previously noted bead segment 38 located upon the probe surface that mates with an arcuate shaped cove 42 that is contained in the inner wall 53 of the cover adjacent to the proximal end flange 40. The cove preferable extends circularly about the axis of the cover and services each of the detent beads. The cover wall section that encircles the cove provides a weaker section in the cover about which the cover can flex when an upward force is applied to the outer face 56 of the flange. A circular camming surface 58 is contained in the outer face of the flange that runs along the rim of the flange. The camming surface 58 is angularly offset with regard to the axis of the cover. The distal end of the two fingers 35 of the ejector mechanism is provided with a arcuate surface 60 that is arranged to ride in contact with camming surface 58 as the ejector mechanism moves between the first and second positions. Surface 60 thus serves as a cam follower in this system. Although surface 60 is shown to be arcuate in form, it can, in practice, be a flat surface that rides in sliding contact with camming surface 58 without departing from the teachings of the present invention. [0033] Fig. 7B shows the probe cover 10 in a locked position with the snap fitting closed, thereby securing the cover to the probe. At this time, the ejector mechanism is in the cover locking position. Moving the ejector button forward moves the cam follower against the camming surface of flange, causing the lower portion of the cover to flex about the weakened wall section which surrounds the cove 42. Sufficient flexure is provided to free the detent beads 38 from the cove 42, thus releasing the cover from the probe. As shown in Fig. 8, further forward movement of the ejector moves the cover well clear of the probe surface so that it can fall easily from probe under the influences of gravity.

[0034] A series of semi circular tabs 65 are circumferentially spaced upon the outer face of the flange that are arranged to mate with openings 66 in the raised shoulder 30 of the probe, such that the snap-on fittings will mate properly at the time of closure. [0035] Turning now to Figs. 9A and 9B, there is illustrated a second embodiment of the invention in which the probe cover is generally referenced 70. In this embodiment, the probe cover 70 is also equipped with a series of snap-on fittings 50 as described above. The cove that is formed in the inner wall of the cover body adjacent to the flange is also provided with a weakened section about which the flange can flex. A circular groove 63 is provided in the outer face of the flange which contains a camming surface 65 that is angularly offset with regard to the longitudinal axis of the probe. The end 67 of each ejector mechanism finger 35 is arcuately shaped and acts as a cam follower that rides in sliding contact with the camming surface 65. Again, as the ejector is moved from the first cover locking position to the second release position, each snap-on fitting 50 is opened and the cover is released from the probe.

[0036] As noted, it is the general practice to package and ship the covers in stacks. A number of probe covers 10-10 are illustrated in Fig. 10 in a stacked configuration. When stacked one on top of the other, the semi circular tabs on the upper cover are arrange to seat upon the flange of the underlying cover to prevent the outer wall surface of the lower cover from moving into binding contact with the inner surface of the upper cover. In addition, the inclined edge surfaces 58 on the outer face of cover flange 40 provide an easily accessible space between each of the cover which can be utilized to further facilitate removal of individual covers from the stack.

[0037] While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof to adapt to particular situations without departing from the scope of the invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims.