Abstract:
A speculum provides visual access to a body cavity, and such instrument is used by physicians for vaginal examination. The speculum comprises a handle having a frontal portion and a rear portion slidingly secured to the frontal portion. A blade angle positioner is pivotally connected by a pivot connection in a top end portion of the handle rear portion, whereby to angulate a top blade removably secured to a top blade connector anchor at a forward projecting end of the blade angle positioner. The handle frontal portion has a bottom blade connector anchor in a top forward end portion thereof. The top and bottom blades each have a connecting end provided with clamp connectors for removable engagement with a respective one of the top and bottom blade connector anchors. The blade angle positioner arrests the handle rear portion at a desired selected position by transfering a biasing force applied onto the blades when inserted into a body cavity and the blade connected to the blade angle positioner is in tension with cavity walls.

Description:
TECHNICAL FIELD 
   The present invention relates to a medical diagnostic instrument, and particularly to a speculum to provide visual access to a body cavity, such as a vaginal cavity. 
   BACKGROUND ART 
   A speculum is a diagnostic instrument used by physicians, and particularly gynecologists, for dilating the opening of the vaginal cavity in order that the interior may be more easily visible for observation. The speculum has two expandable blades that are inserted into the vagina in a closed condition and then expanded or moved apart for dilating the vaginal cavity. The speculum is usually a plastic molded instrument formed from a hard, clear and nontoxic plastic resin to be economically manufactured. 
   Most specula known provide adjustment of the blades from a retracted position to an open position, where the spatulas or blades are laterally displaced from one another. It is also desirable to angulate one of the spatulas or blades to create a larger internal opening. It is also known to provide specula with replaceable blades. Examples of such specula can be found, for example, in U.S. Pat. Nos. 3,762,400 and 3,851,642. These specula permit the blades to be disposed in different positions, and this is usually dependent on the comfort of the patient and the nature of the observation required by the physician. Known specula provide very few adjustments, and often this results in discomfort for the patient, as the speculum blades may apply excessive pressure to the walls of the body cavity, as well as being susceptible to causing pinching. 
   As previously described, it is also known to provide a speculum with interchangeable blades, as, for example, described in U.S. Pat. No. 3,762,400. However, these blades are attached on support members in such a way that they are not entirely sanitary, and it is essential to disinfect or sterilize these supports prior to mounting a displaceable blade thereover. Most known specula are of the type that are discarded after use, and this results in waste. A gynecologist can often use twenty of these instruments per day of work and, accordingly, there is excessive waste of plastics material, and this becomes costly to the physician. It also requires excessive storage space in his examination room. The consumption from private practice combined with hospital volume results in excessive plastic wastes. Such instrument which is discarded after use also represents higher costs to the end-user. In addition, it also requires more storage space while providers pay higher freight costs in view of the bulk packaging. 
   For years, specula have been made of metal and intended for longer procedures. Disinfection and/or sterilization have to be done; however, sterilization does not provide a full satisfactory efficiency in regard that all known infectious agents (eq. viruses) are not totally destroyed. Over recent years appeared plastic (disposable) specula which were of relatively inexpensive manufacturing. 
   Most recently, a general concern happened on the effects of discarding instruments in the environment. The present invention offers an economically manufacturing opportunity along with the combined effects form the metal and disposable specula: a more complete range of adjustments (angular and elevational) and a safe/efficient examination by discarding only the spatulas after use. 
   Spatulas as above referred are of a type that permits only rotary or arcuate relative movement of the spatulas (blades). As such, there is a pivotal or hinged connection provided between the two blades. In addition to this angular rotation of the blades, it is necessary that the blades be bodily adjustable relative to each other. Therefore, the instrument should not only permit substantial angular rotation of the blades but should also permit relative linear bodily adjustment. 
   SUMMARY OF INVENTION 
   It is a feature of the present invention to provide a speculum available in different sizes of lengths and width and wherein the blades are removably secured to the speculum by a simple clamping connection and wherein the handle assembly is reusable. 
   Another feature of the present invention is to provide a speculum having multi-positionable configurations to provide more comfort to the patients and to provide a greater range of adjustments of the speculum during an examination procedure. The reusable portion of the speculum (eq. handle) retains a fixed plastic component (eq. light pipe) which can be connected to conventional optical means to achieve a better visualization of the internal tissues. 
   A further feature of the invention relates therefore to the possibility to select among seven (7) elevations a combining effect of four (4) angular and/or linear positions. 
   According to the above features, from a broad aspect, the present invention provides a speculum to provide visual access to a body cavity. The speculum comprises a handle having a frontal portion and a rear portion slidingly secured to said frontal portion. A blade angle positioner is pivotally connected by a pivot connection in a top end portion of the handle rear portion whereby to angulate a top blade removably secured to a top blade connector anchor at a forward projecting end of the blade angle positioner. The handle frontal portion has a bottom blade connector anchor in a top forward end portion thereof. The top and bottom blades each have a connecting end provided with clamp connectors for removable engagement with a respective one of the top and bottom blade connector anchors. The blade angle positioner arrests the handle rear portion at a desired selected position by transferring a biasing force applied onto the blades when inserted into the body cavity and said blade connected to said blade angle positioner is placed in normal tension with cavity walls. The handle rear portion is retained in sliding fit in a guide slot formed in each of a pair of strait vertical side edges of the handle frontal portion. The guide slots each have a serrated section facing forwardly. The handle rear portion has a pair of transversely aligned serration-engaging teeth facing rearwardly and adapted to engage with a respective one of each serrated sections at a desire position therealong when the biasing force is a lied onto the blade. The blade angle positioner is provided with an integrally formed angle-selecting flexible ramp which is integrally molded therewith. The ramp has a series of teeth displaceable against a teeth-engaging edge of the handle rear portion when the angle positioner is displaced on the pivot connection. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which: 
       FIG. 1  is a perspective view of a speculum constructed in accordance with the present invention; 
       FIG. 2  is a side view of the speculum; 
       FIG. 3  is a rear view of the speculum; 
       FIG. 4A  is a perspective view of the blade angle positioner; 
       FIG. 4B  is a side view of  FIG. 4A ; 
       FIG. 4C  is a top view of  FIG. 4B ; 
       FIG. 5  is a cross-section view along section lines V-V of  FIG. 2 ; 
       FIG. 6A  is a perspective view of the detachable blade; 
       FIG. 6B  is a side view of  FIG. 6A ; 
       FIG. 7A  is a perspective view of the handle frontal portion; 
       FIG. 7B  is a side view of  FIG. 7A , illustrating the position of the guide slot; 
       FIG. 7C  is a front view of  FIG. 7B ; 
       FIG. 8A  is a perspective view of the rear sliding portion of the handle; 
       FIG. 8B  is a sectional side view of  FIG. 8A ; 
       FIG. 8C  is a fragmented section view showing the position of the serration-engaging teeth with respect to the serrated section of the guide slot and the position of the force transfer projecting finger relating thereto; 
       FIG. 9A  is a perspective view of a removable light pipe; and 
       FIG. 9B  is a top side view thereof. 
   

   DESCRIPTION OF PREFERRED EMBODIMENTS 
   Referring now to the drawings, and more particularly to  FIGS. 1 to 3 , there is shown generally at  10  the multi-positionable vaginal speculum of the present invention. The speculum as herein shown comprises a handle assembly formed by a handle frontal portion  11  and a sliding rear handle portion  12 , which is detachably secured to the frontal portion  11 . A blade angle positioner  13  is pivotally connected by a pivot connection  14  in a top end portion of the handle rear portion  12 , whereby to angulate a top blade  15 , which is removably secured to a connector anchor  16  (see  FIGS. 4A to 4C ) integrally formed at a forward projecting end  17  of the blade angle positioner  13 . 
   The handle frontal portion  11  is also provided with a bottom blade connector anchor  18  to detachably secure the bottom blade  19  thereto. 
   With reference now to  FIGS. 4A to 4C , and  7 A to  7 C, there is shown the construction of the blade connector anchors  16  and  18 . In both cases, these anchors are identical in construction, and only one of these will be described with reference to  FIGS. 7A and 7C . As herein shown, the connector anchor  18  is comprised of an arcuate guide ridge  20 , having opposed locating cavities  21  and  21 ′ at opposed ends of the ridge, whereby to receive in snap-fit clamping engagement therein the clamp connectors of the blades. As shown in the cross-section view of  FIG. 5 , these clamp connectors  22  and  22 ′ are constituted by a pair of opposed inwardly facing shoulders, each disposed at an opposed end of an arcuate connector channel  23 , forming an inner wall of the connecting end of the blades. The arcuate guide ridge  20  is received in close fit in the channel  23 . The blades are connected by placing the arcuate ridge  20  with its locking cavity  21  in engagement with the clamping connector  22 , and pressing the arcuate ridge  20  into the cavity  23  to permit the cavity  21 ′ to snappingly engage with the clamp connector  22 ′. To disconnect the blades, they are merely twisted out of engagement. It is pointed out that the spatulas or blades are made of polystyrene and the handle components are constructed of polycarbonate. Both plastic resins are compatible with each other offering flexibility for the snap-fit clamping engagement of the blades. The transparency of the spatulas are important for diagnostic purposes. Among several advantages, they are non-toxic, light weight, resistant to pressure, compatible with most disinfecting agents and the handle can sustain sterilization. 
   Referring now to  FIGS. 7A to 7C , there is shown the construction of the handle frontal portion  11 , which is generally a U-shaped member defining opposed straight vertical side edges  25  rearwardly of the frontal portion. A guide slot  26  is formed in each of the vertical side edges  25 , and has a bottom opening  27  to permit entry and displacement of a serration-engaging tooth  28  and a force transfer projecting finger  29  secured to the rear handle portion  12 . The back wall  30  of the guide slot  26  is provided with a serrated section  31  disposed in a lower portion of the slot. The uppermost portion  32  is provided with a smooth inner wall. The serrations or teeth  31 ′ of the serrated section  31  face forwardly of the frontal handle portion  11 . 
   As shown in  FIGS. 8A and 8B , the rear handle portion  12  is also of a substantially U-shaped cross-section, and it has a pair of these force transfer projecting fingers  29  projecting inwardly from a rear edge  35  thereof. The serration-engaging tooth  28  also projects from this rear edge  35 , but in a lower portion of the rear handle portion  12 . These elements  29  and  28  are positioned into the guide slot from the bottom opening  27  of the slot, and are free to move therealong as the rear handle portion slides up and down with respect to the guide slot. The rear handle portion  12  is maintained in engagement with the guide slot by the blade angle positioner  13 , which is connected to the rear handle portion  12  via the pivot connection  14 . Accordingly, the rear handle portion  12  is retained captive in the handle assembly by the blade angle positioner. To detach the component parts of the blade assembly, it is only necessary to flex the upper side walls  12 ′ of the rear handle portion  12  to disconnect the pivot connections with the blade angle positioner. As shown in  FIG. 8A , these upper portions or wings  12 ′ can flex outwardly due to the large cut-out cavity  36  provided in the top portion of the rear handle portion  12 . Pivot pin connectors  37  are located on the inside wall  12 ″ of the upper wing portions  12 ′. The upper part of the cavity  36  provides for a sighting aperture  38 , as shown in  FIG. 3 , whereby to provide visibility to a user person to the area between the blades. 
   Referring now to  FIGS. 4A to 4C , the construction of the blade angle positioner  13  will be described. As herein shown, the top portion  40  of the blade angle positioner has a curvate wall, which, together with the cavity  36  in the rear handle portion, provides a large sighting aperture  38 . Pivot pins  41  extend outwardly on a common transverse axis to be receivably connected within the connectors  37  of the rear handle portion. The lower extension portion  42  of the blade angle positioner is dimensioned to fit within the lower portion of the cavity  36  in the rear handle portion as illustrated in  FIGS. 1 to 3 . 
   As better shown in  FIG. 4B , the lower extension portion  42  of the blade angle positioner  13  is provided with a flexible ramp  43 , integrally molded therewith. The ramp  43  is connected at the front end portion  44  thereof to the lower extension portion  42  of the positioner. The ramp  43  is a narrow plastic strip  45 , as shown in  FIG. 4C , provided with a series of teeth  46  on an outer face thereof. The teeth  46  are integrally formed with the flexible ramp. The flexible ramp  43  also has a finger-engaging projection  47  at a free end thereof to displace the flexible ramp  46  inwardly of the lower extension portion  42 , as indicated by arrow  48  in  FIG. 4B , whereby to disconnect the teeth  46  from engagement with the lower engaging edge  49  of the cavity  36 , as shown in  FIG. 8A . There are four of the teeth  46  formed in the flexible ramp, which are biased outwardly against the engaging edge  49  of the rear handle portion. 
   Having thus described the components parts of the handle assembly and the connection of the removable blades to the handle assembly, and the angle positioner, the operation of the speculum will now be described. 
   When the speculum  10  is positioned in a body cavity, the top and bottom blades are in a closed condition, that is to say, the blades at the insertion are against each other. The closed blades are then inserted into the body cavity and with a slight rotation to allow the examination of the vaginal cavity through a 360 degree opening view, they then become separated as shown in  FIGS. 1 to 3  by sliding the rear handle portion  12  upwardly with the serration-engaging tooth  25  moving upwardly over the serrated section  31  within the guide slot  26 , as shown in  FIG. 8C . Likewise, the force transfer projecting finger  29  moves upwardly until the blades are separated to a desired position. As the blades are separated apart, they are in contact with side walls of the cavity, and this places the blades in tension. Accordingly, a force is applied against the blades, as illustrated by arrows  50  in  FIG. 2 . This tension or force is transmitted along the top blade  15  to the pivot connection  14 , urging the blade angle positioner  13  to exert a movement around the pivot pin  14 , as indicated by arrow  51  in  FIG. 2 . This movement applies an outward force as indicated by arrow  52  on the lower portion of the positioner  13  below the pivot pin. Because the flexible ramp  43  is in toothed engagement with the engaging edge  49 , this outward force, as indicated by arrow  52 , is applied against the rear handle portion  12  due to the pulling action of the positioner. This causes the force transfer projecting finger  29  to move against the inner surface  32 ′ of the upper portion  32  of the slot (see  FIG. 8C ), providing a pivot point to maintain the serration-engaging tooth  28  in engagement with an adjacent tooth  31 ′ of the serrated section  31  formed in the rear wall  32 ′ of the guide slot  26 . Accordingly, the speculum component parts are all interconnected together at a desired position. 
   In order for the physician to displace the removable blades with respect to one another, there is provided on the rear wall of the rear handle portion  12  a thumb cavity  55 , and, by depressing that cavity, the serration-engaging tooth  28  and the force transfer projecting fingers  29  are displaced rearwardly to disconnect from the inner surface  32 ′ and the serrated section  31  of the slot  26 . Thus, the rear handle portion  12  can be slid up or down to open or close the spacing between the blades  15  and  19 . Once an ideal position has been reached, the thumb is removed from the thumb cavity. In order to angulate the top blade  15 , all that is necessary is to exert an upward push on the tongue  47  to draw the flexible ramp  43  inwardly of the lower wall of the lower portion of the blade angle positioner  13 , and to push the lower portion inwardly or to release it outwardly, causing the positioner to pivot on the pivot  14  to assume one of four desired open positions, one of which is illustrated at  56  in phantom line in  FIG. 2 . 
   As previously described, there are four teeth-engaging positions, and there are seven teeth  31 ′ in the serrated section  31  of the guide slot. Accordingly, this provides to the physician with twenty-eight different positions or configuration possibilities of the speculum blades, whereby to achieve better placement of the blades to suit the comfort of a patient, or to provide better access to parts of the body cavity being inspected. 
   As shown in the drawings, and more specifically in  FIGS. 1 to 3 , and  7 A to  7 C, the frontal handle portion  11  is further provided with a light source channel  57 . The channel has an open top end  58 , configured to receive a removable light pipe  59 , as illustrated in  FIGS. 9A and 9B . As herein shown, the light pipe has a connector end  60 , which fits into the open top end  58 , and an angulated light-conducting solid plastic gooseneck  61 , the free end  62  of which is positioned in the channel  63  (see  FIG. 1 ) of the upper section of the handle frontal portion  11 , whereby to direct a light beam between the blades  15  and  19 . A light-dispersing dome  64  directs light from an optic fiber or other light conductor (not shown), and such a light pipe is well known in the art and is merely described as an accessory to the speculum of the present invention. 
   Because of the construction of the speculum  10 , the handle assembly is reusable and only the blades are discarded. The handle portion is easy to assemble and compact. It provides multiple adjustments of the blades and improved visibility to a body cavity. 
   It is within the ambit of the present invention to cover any obvious modifications of the preferred embodiment described herein, provided such modifications fall within the scope of the appended claims.