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BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a refuse collection device for collecting refuse in a flexible container, such as a plastic bag, and in particular to a mechanism for readily and releasably retaining the collection bag on the refuse collection device. 
     2. The Related Art 
     Collecting refuses, especially animal droppings, is always a disgusting job. To help people collecting the refuses without using hand to directly pick up the refuses, there are a variety of refuse collection devices proposed and available in the market. One example of the known refuse collection devices is U.S. Pat. No. 6,019,405 issued to the applicant. The known device comprises a flexible container for receiving the collected refuse. The container is attached to the device by means of resiliency of the container itself. However, the known device suffers the disadvantage that opening of the container cannot be securely fixed to the device, leaving a portion of the container unfixed. This leads to poor protection of the device for contamination by the refuse collected in the container. 
     Thus, it is desired to have an improvement of the refuse collection device to overcome the above-discussed problems. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a refuse collection device comprising a retention mechanism for securely attaching a collection container [[to]] thereto while allowing the container to be readily detached from the device without hand touching the container. 
     Another object of the present invention is to provide a refuse collection device that is completely protected from contamination caused by the refuse collected therein. 
     A further object of the present invention is to provide a refuse collection device comprising a retention mechanism for securely fixing opening end of a collection container to the device in order to enhance collection of refuses. 
     Yet a further object of the present invention is to provide a refuse collection device comprising a retention mechanism which allows for ready mounting of a collection bag to the device while securely fixing the bag to the device without causing undesired contamination of the device. 
     To achieve the above objects, in accordance with the present invention, there is provided a refuse collection device comprising an upright tubular portion having a lower end to which a bag mount is formed. The bag mount includes a lower section and an upper section spaced from each other to define a refuse passage. A flexible bag, such as a plastic bag, has a front opening fit over the upper and lower sections and is thus attached to the bag mount for receiving refuses through the refuse passage. The bag is comprised of first and second sheets, each having a front edge folded over the upper and lower sections of the bag mount. The front edge of the first sheet forms a cut line dividing the front edge into two opposite free flaps for facilitating mounting the bag to the bag mount. A flap retainer is mounted to the tubular portion and is biased by a torsional spring to securely fix the flaps to the bag mount thereby preventing the flaps from arbitrarily moving within the refuse passage and thus enhancing collection of refuses into the bag. The torsional spring has a small spring constant that is only sufficient to overcome inherent resiliency of the flaps for effectively retaining the flaps in position while causing no substantial interference with mounting and dismounting of the bag to and from the bag mount. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, in which: 
     FIG. 1 is a perspective view of a refuse collection device constructed in accordance with the present invention; 
     FIG. 2 is an exploded view of the refuse collection device of the present invention; 
     FIG. 3 is a side elevational view, partly sectioned, of the refuse collection device in a closed condition with a refuse collection container attached thereto; 
     FIG. 4 is similar to FIG. 3 but showing the refuse collection device in an open condition; 
     FIG. 5 is similar to FIGS. 3 and 4 but showing the refuse collection device in a dumping condition; 
     FIG. 6 is a perspective view of the refuse collection device in accordance with the present invention and a refuse collection container and a cover envelop that are shown detached from the refuse collection device; 
     FIG. 7 is a side elevational view, partially sectioned, of the refuse collection device of the present invention with the refuse collection container and the cover envelop attached thereto; and 
     FIG. 8 is a perspective view of the refuse collection device with the refuse collection container and the cover envelop attached thereto. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference to the drawings and in particular to FIGS. 1-3, a refuse collection device constructed in accordance with the present invention, generally designated with reference numeral  10 , comprises an elongated rod or tubular portion  12  which in general use is substantially upright with an axis thereof extending in a vertical direction, having a lower end (not labeled) supporting a bag mount  14  to which a flexible refuse collection container  16 , such as a plastic bag (see FIGS.  6 - 8 ), is detachably mounted and openably closed by a cover  18  and an upper end (not labeled) to which a control  20  is mounted to selectively open the cover  18  for collecting refuse (not shown) into the refuse collection container  16 . 
     The elongated rod portion  12  of the refuse collection device  10  comprises an outer tube  22  and an inner tube  24  telescopically received in the outer tube  22  whereby the outer tube  22  is axially movable with respect to the inner tube  24  between a lower closed position (FIG. 3) and an upper open position (FIG.  4 ). The outer tube  22  may be further moved to a dumping position (FIG. 5) beyond the upper open position. All these positions will be further discussed. Each of the tubes  22 ,  24  has an upper end and an opposite lower end. The lower end of the inner tube  24  extends beyond the lower end of the outer tube  22  with the bag mount  14  fixed thereto for supporting the refuse collection container  16 . 
     The bag mount  14  comprises a semi-circular frame (not labeled) having a lower flat section  26  positionable on the ground G as shown in FIG.  4 . For example, the bag mount  14  may be positioned in front of a refuse R, such as an animal dropping (shown in phantom lines in FIG. 4 for illustration purposes), and an arc upper section  28  connected to the flat section  26  to define therebetween a refuse passage  29 . The bag mount  14  comprises a hollow projection  30  extending from the arc upper section  28  (preferably an upper apex thereof) in a vertically upward direction substantially perpendicular to the lower flat section  26 . The projection  30  defines a central bore  32  into which the lower end of the inner tube  24  is inserted. The inner tube  24  is fixed to the projection  30  of the bag mount  14  by any known means, such as welding, bolt-nut pairs or force fitting. A cover support  38  is formed on the projection  30  of the bag mount  14  and extends in a transverse direction. A through hole  40  is defined in the cover support  38 . 
     The cover  18  comprises a semi-circular plate  42 , substantially corresponding in shape and size to the semi-circular frame of the bag mount  14 . The semi-circular plate  42  comprises two lugs  44  extending therefrom and spaced from each other. The lugs  44  define aligned holes  46  corresponding to the through hole  40  of the cover support  38  of the projection  30  of the bag mount  14  for the extension of a pivot pin  48  therethrough. This allows the cover  18  to rotate about the pivot pin  48  with respect to the bag mount  14  (as well as the projection  30 ) and thus making the semi-circular plate  42  of the cover  18  movable relative to the bag mount  14  between a closed position (FIG. 3) and an open position (FIG. 4) for closing/opening the refuse passage  29  defined between the upper section  28  and the lower section  26  of the bag mount  14 . 
     A biasing element  50  is provided between the cover support  38  and the cover  18  to bias the cover  18  toward the closed position for normally closing the refuse passage  29  of the bag mount  14 . The refuse passage  29  of the bag mount  14  is normally closed by the cover  18  under the biasing force of the biasing element  50  and can only be opened by manually moving the cover  18  against the biasing element  50  which will be further discussed. This prevents the refuse collected in the refuse collection container  16  that is mounted to the bag mount  14  from accidentally getting out of the refuse collection container  16  and causing a second time contamination. 
     In the embodiment illustrated, the biasing element  50  comprises a torsional spring, having a U-shaped configuration comprising two limbs connected by a bottom (both not labeled for simplifying the drawings). Each limb of the U-shaped configuration forms a coil  52  and has a free end  54 . The pivot pin  48  of the cover  18  extends through the coils  52  for supporting and retaining the biasing element  50  in position. The bottom of the U-shaped configuration is attached to and supported by the projection  30  of the bag mount  14  and each free end  54  of the U-shaped configuration is fixed to the cover  18  by inserting into a slot  441  defined between each lug  44  and support plate  56  adjacent to and opposite to the lug  44  whereby the spring exerts the biasing force between the cover  18  and the cover support  38  of the bag mount  14 . 
     A connection link  58 , substantially U-shaped, has a bottom section  59  attached to the outer tube  22  by a retainer  60  and two side sections  61  each having a free end forming a hook  62  engaging a sideway-projecting pin  64  extending from each lug  44  of the cover  18  and having an expanded end  641 . The connection link  58  allows the user to open the cover  18  by axially moving the outer tube  22  with respect to the inner tube  24  in an upward direction from the closed position to the open position. By moving the outer tube  22 , the retainer  60  that is fixed to the outer tube  22 , drives the cover  18 , via the connection link  58 , to rotate about the pivot pin  48  from the closed position to the open position for exposing the refuse passage  29  of the bag mount  14 . 
     The retainer  60 , which can be made of molded plastics, comprises a cylindrical body  66  snugly fit over the lower end of the outer tube  22 . Two resilient fingers  68  are formed on opposite sides of the cylindrical body  66 , each having a free end forming a barb  70  engaging a corresponding slot  72  defined in the outer tube  22  thereby attaching the retainer  60  to the outer tube  22 . Upper and lower retaining boards  74 ,  76  extend transversely from the cylindrical body  66 . Notches  78 ,  80  are defined in the upper and lower retaining boards  74 ,  76 . In the embodiment illustrated, two lower boards  76  are provided and are spaced from each other with a single upper board  74  located above the lower boards  76  and at a position substantially midway between the lower boards  76 . The notches  78 ,  80  of the upper and lower boards  74 ,  76  have arc configuration and are complementary to each other whereby the notches  78 ,  80  together, when viewed sideways, form a circular channel in which the bottom section  59  of the connection link  58  is accommodated. Thus, the bottom section  59  of the connection link  58  is seated in the notches  78 ,  80  whereby the bottom section  59  of the connection link  58  is gripped by and pinched between the upper and lower boards  74 ,  76 . It is apparent to those having ordinary skills to replace the upper and lower boards  74 ,  76  with other structure to retain the bottom section  59  of the connection link  58 . 
     The control  20  comprises a movable handle  82  mounted to the upper end of the outer tube  22  and a fixed handle  92  mounted to the upper end of the inner tube  24 . The movable handle  82  comprises a handle bar  84  pivotally mounted to the movable handle  82  by a pivot  841  whereby the handle bar  84  is movable with respect to the movable handle  82  between a released condition and an erected condition where the handle bar  84  extends transversely from the movable handle  82 . The movable handle  82  further comprises a cylindrical sleeve  86  mounted to the upper end of the outer tube  22  whereby the movable handle  82  is movable in unison with the outer tube  22 . If desired, the sleeve  86  can be separated from the movable handle  82  and integrally formed with the outer tube  22 . A central bore  88  is defined in the cylindrical sleeve  86 . A multi-stepped groove  90  (FIG. 3) is defined in an inside surface (not labeled) of the bore  88  of the sleeve  86 . The structure of the multi-stepped groove  90  is disclosed in detail in the above mentioned U.S. Pat. No. 6,019,405 and thus no further description will be given herein. 
     The fixed handle  92  comprises a handle bar  111  corresponding in spatial position to the handle bar  84  of the movable handle  82 . Preferably, the handle bar  111  of the fixed handle  92  is detachably mounted to the fixed handle  92 . For example and as illustrated in the drawings, a threaded extension  110  transversely extends from the fixed handle  92  and threadingly and thus detachably engages an inner threading  94  of the handle bar  111  to mount the handle bar  111  to the fixed handle  92  for allowing the user to hold the refuse collection device  10  in a direction facing a refuse R to be collected for best operation of the refuse collection device  10 . A hollow shaft  96  extends from the handle  92  and is axially and movably received in the central bore  88  of the sleeve  86 . The hollow shaft  96  has a lower end (not labeled) securely fixed to the upper end of the inner tube  24 . (Alternatively, the hollow shaft  96  can be made an integral part of the inner tube  24 .) The hollow shaft  96  is provided with a plurality of radially extending openings  98  around a circumference thereof to each movably receive a spherical member  100  whereby the spherical members  100  are allowed to partly move in and out of the multi-stepped groove  90  of the sleeve  86 . The openings  98  are sized to allow the spherical members  100  to freely move therethrough. In the embodiment illustrated, there are two openings  98  formed on the shaft  96  and arranged to be diametrically opposite to each other. 
     The control  20  further comprises a shank  102  axially and movably received in the hollow shaft  96 . The shank  102  forms a multi-stepped groove  104  formed on a lower end thereof and corresponding in position to the openings  98  of the hollow shaft  96 . The structure and operation of the multi-stepped groove  104 , as well as the spherical members  100  and the multi-stepped groove  90  of the sleeve  86 , are disclosed and taught in the above-mentioned U.S. Pat. No. 6,019,405 and thus no further discussion is needed herein. 
     The shank  102  has an expanded upper end forming a pushbutton  106 . The fixed handle  92  forms a recess  108  in an upper surface (not labeled) thereof for movably receiving the pushbutton  106  therein. Biasing means, such as helical spring  107 , is disposed between the pushbutton  106  and the recess  108  for biasing the pushbutton  106  to a non-actuated position, which will be further discussed. 
     A driving link  200  extends downward from the fixed handle  92  and extends through a slot  201  defined in the movable handle bar  84  of the movable handle  82 . Sideways projections  202  extend from a lower free end (not labeled) of the driving link  200  in opposite directions whereby when the outer tube  22  is moved to the lower position (FIG.  3 ), the projections  202  engage opposite sides of the slot  201  of the movable handle bar  84  and maintain the movable handle bar  84  at the erected condition to allow hand holding by the user for moving the outer tube  22  from the lower position toward the upper position and even the dumping position. When the outer tube  22  is moved to the upper position as shown in FIG. 4, the movable handle bar  84  is no longer supported by the projections  202  and is thus allowed to move to the released condition, clearing the space below the handle bar  111  of the fixed handle  92  for convenience of operation. 
     A bag release  112  is rotatably mounted to the projection  30  of the bag mount  14  substantially opposite to the cover  18 . The bag release  112  has a U-shaped configuration having two spaced side sections  114  and a connection section  116  connected between the side sections  114 . The side sections  114  are located on opposite sides of the projection  30  and define aligned holes  118  for receiving a pivot pin  120  which is mounted to the projection  30 , such as extending through holes  122  defined in the projection  30 , whereby the bag release  112  is movable with respect to the bag mount  14  between a bag-holding position (corresponding to the closed and open positions of the outer tube  22  and the cover  18  as shown in FIGS. 3 and 4) and a bag-releasing position (corresponding to the dumping position of the outer tube  22  and the cover  18  as shown in FIG.  5 ). In the bag-holding position, the connection section  116  of the bag release  112  is substantially horizontal, or even slightly upward inclined, for engaging and supporting an edge of the refuse collection container  16 . The refuse collection container  16  is thus tightly fixed between the bag release  112  and the bag mount  14  (especially the flat section  26  of the bag mount  14 ). When the bag release  112  is moved to the bag-releasing position (in response to the movement of the outer tube  22  and the cover  18  toward the dumping position), the connection section  116  is slightly inclined downward, allowing the bag  16  to slip off of the bag release  112  and thus automatically removing the refuse collection container  16  from the refuse collection device  10 . 
     A biasing element  124  is arranged between the bag release  112  and the bag mount  14  to bias the bag release  112  to the bag-holding position. The biasing element  124  comprises a U-shaped spring having two limbs each forming a coil  126  through which the pivot pin  120  extends for supporting and retaining the biasing element  124  in position. The limbs of the biasing element  124  has free end  128  received and retained in slots  130  defined in the side sections  114  of the bag release  112  for supporting and biasing the bag release  112  to the bag-holding position. 
     The side sections  114  of the bag release  112  have proximal ends  132 . The ends  132  of the bag release  112  are located and dimensioned to be engageable by the lugs  44  of the cover  18  whereby when the cover  18  is moved from the open position to the dumping position, the lugs  44  thereof engage the ends  132  of the bag release  112  and initiate rotation of the bag release  112  with respect to the projection  30  of the bag mount  14 , thereby tilting the bag release  112  to release the refuse collection container  16  from the bag mount  14 . 
     Also referring to FIG. 4, to collect refuses, with the cover  18  opened, one may position the refuse collection device  10  next to the refuse R with the refuse passage  29  of the bag mount  14  facing the refuse R. To open the cover  18 , one may move the movable handle  82  toward the fixed handle  92  whereby the cover  18  is driven by the outer tube  22  via the connection link  58  to the open position (FIG.  4 ). The outer tube  22  and thus the cover  18  are maintained in the open condition by the spherical members  100  engaging the multi-stepped grooves  90 ,  104  of the sleeve  86  and the shank  102 . This is described in detail in the above-mentioned U.S. Pat. No. 6,019,405 and constitutes no novel part of the application. Thus, no detail regarding the operation of the spherical members  100 , as well as the multi-stepped grooves  90 ,  104 , is given herein. 
     Thereafter, by depressing the pushbutton  106  against the spring  107  from the non-actuated position to an actuated position, the shank  102  is forced downward and the engagement between the spherical members  100  and the multi-stepped grooves  90 ,  104  of the sleeve  86  and the shank  102  that maintains the cover  18  in the open position is broken. The cover  18  is driven back to the closed position by the biasing force of the biasing element  50 . With the refuse R to be collected located in the path of the movement of the cover  18  when the cover  18  moves from the open position to the closed position, the cover  18  hits and scoops the refuse into the refuse collection container  16 . 
     To dispose the collected refuse, the refuse collection container  16  is detached from the bag mount  14  without the user&#39;s hand(s) directly touching the refuse collection container  16 . This is done by manually moving the movable handle  82  toward the fixed handle  92  with the cover  18  moving from the closed position and passing the open position and toward the dumping position as shown in FIG.  5 . The bag release  112  that supports the refuse collection container  16  on the bag mount  14  is tilted thereby releasing the refuse collection container  16  from the bag mount  14 . 
     The bag release  112  and the cover  18  are maintained in the dumping position by the spherical members  100  as described in the above mentioned U.S. Pat. No. 6,019,405. To release the cover  18  from the dumping position shown in FIG. 5, one may simply depress the pushbutton  106  to move the shank  102  downward so as to break the engagement between the spherical members  100  and the grooves  90 ,  104  that maintains the cover  18  in the dumping position. The cover  18  is now allowed to move downward along the arc path P (FIG. 4) and thus closing the cover  18 . 
     Referring back to FIGS. 3-5, the bag mount  14  has an inclined side profile whereby the flat section  26  of the bag mount  14  is spaced from a position corresponding to the pivot pin  48  of the cover  18  in the vertical direction and a distance D therebetween is sufficient to provide a space for accommodating the refuse R to be collected at a position substantially corresponding to the pivot pin  48  of the cover  18  in the vertical direction. This allows the refuse R to be positioned at the lowermost point of the path P of the cover  18  whereby the cover  18  hits the refuse R with the greatest speed that the cover  18  in a most complete way. 
     In addition, since the refuse R is located at the lowermost point of the path P of the cover  18 , the cover  18  can hit almost all of the refuse R to completely move the refuse R into the container  16 . 
     Referring to FIGS. 6-8, in the embodiment illustrated, the refuse collection container  16  is made of plastics as a plastic bag, comprising two opposite and spaced plastic sheets  300 ,  302  sealed together along a rear edge  161  and two lateral edges  162  to define a front opening  163  for fitting over the bag mount  14 . It is apparent that the refuse collection container  16  can be made of other materials, such as paper sheet with wax coating. Two cut lines (not labeled) are formed in the first plastic sheet  300  and extend from the front edge  164  of the first plastic sheet  300  to a desired length whereby a strip  304  is formed with one end  305  attached to the first plastic sheet  300  and the first plastic sheet  300  forms two flap portions  312  on opposite sides of the strip  304 . The strip  304  has a free end  307  extending beyond the front edge  164  of the first plastic sheet  300 . A reference mark  306  is printed on the second plastic sheet  302 . 
     To mount the plastic bag  16  to the bag mount  14 , the bag  16  is widely opened with the lower flat section  26  of the bag mount  14  positioned on an inner surface of the second plastic sheet  302  substantially corresponding to the reference mark  306 . The first plastic sheet  300  is slightly stretched and fit over the bag release  112 . This retains the bag  16  on the bag mount  14  due to the restoring force caused by the stretching of the bag  16 . The strip  304  may now extend over the arc upper section  28  of the bag mount  14  with the free end  307  thereof engaging a cover envelop  308 , preferably made of plastics in the form of a plastic bag, fit over the cover  18 . In the embodiment illustrated, the cover envelop  308  is coated with an adhesive material  310  to which the free end  307  of the strip  304  attaches. This secures both the bag  16  and the cover envelop  308  in position. The cover envelop  308  helps preventing the cover  18  from being contaminated by the collected refuse. Front portions  400  (FIG. 7) of the first and second plastic sheets  300 ,  302  of the bag  16  are folded inward and over the upper and lower sections  28 ,  26  of the bag mount  14  to substantially shield and prevent the upper and lower sections  28 ,  26  of the bag mount  14  from being contaminated by the collected refuse. 
     To prevent undesired unfolding of the front portions  400  of the first and second plastic sheets  300 ,  302  caused by the inherent resiliency of the plastic material, in accordance with the present invention, a flap retainer  350  is movably attached to the projection  30  of the bag mount  14 . Also referring to FIG. 2, the flap retainer  350  comprises a pivot  352  rotatably received in holes  354  defined in the cover support  38  that is fixed to the projection  30 . The flap retainer  350  is biased by a torsional spring  356  to urge a rounded lower end  358  thereof against the projection  30  by rotating about the pivot  352 . Preferably, the pivot  352  is located at an upper end of the flap retainer  350  and is opposite to the rounded lower end  358 . Due to the folding of the first plastic sheet  300  over the upper section  28  of the bag mount  14  and due to the arcuate configuration of the upper section  28 , the flap portions  312  partially overlap each other on the folded portions thereof. The overlapped portions of the flap portions  312  of the first plastic sheet  300  are positioned between the rounded end  358  of the flap retainer  350  and the projection  30  by manually moving the rounded end  358  against the torsional spring  356  (as shown in phantom lines in FIG.  7 ). The flap portions  312  are thus secured by the flap retainer  350  and this prevents the folded front portions  400  of the bag  16  from undesirably unfolding. To allow for easy operation and due to the fact that the inherent resiliency of the plastic sheets  300 ,  302  is small, the spring constant of the spring  356  is selected to be small and just sufficient to overcome the inherent resiliency of the plastic sheets  300 ,  302 . The small spring constant of the spring  356  also helpful in removing the plastic bag  16  from the bag mount  14  and this will be further discussed. 
     To remove the plastic bag  16  from the refuse collection device  10 , the movable handle  82  is moved to the dumping position, which tilts the bag release  112  and thus loosening the plastic bag  16 . The tubular portion  12  is then held in a substantially horizontal condition with the plastic bag  16  located on the lower side of the bag mount  14  and the cover  18  on the upper side of the bag mount  14 . The plastic bag  16  is thus allowed to detach from the bag mount  14  by means of the gravity of the refuse collected in the plastic bag  16 . At this moment, due to the adhesion connection between the free end  307  of the plastic bag  16  and the cover envelop  308  and further due to the engagement between the cover envelop  308  and the cover  18 , the plastic bag  16  hangs below the tubular portion  12  but is not completely separated from the refuse collection device  10 . As mentioned above, the spring constant of the spring  356  is small whereby the weight of the collected refuse can easily overcome the spring force of the flap retainer  350  to detach the plastic bag  16  from the bag mount. In other words, the spring force of the spring  356  does not interfere with detaching the plastic bag  16  from the bag mount  14 . 
     By rotating the refuse collection device  10  about the tubular portion  12  an angle around 180 degrees, the plastic bag  16  is now moved to the same side of the cover  18  with respect to the bag mount  14  and the gravity of the refuse collected in the bag  16  forces the cover envelop  308  to detach from the cover  18 , making the plastic bag  16  and the cover envelop  308  completely separated from the refuse collection device  10 . Thus, the refuse collected and the plastic bag  16  can be disposed of by simply dropping into a garbage can without any hand contacting the plastic bag  16  and the envelop  308 . Meanwhile, the refuse collection device  10  is completely free of contamination caused by the collected refuse for being protected by the plastic bag  16  and the envelop  308 . 
     Although the present invention has been described with reference to the preferred embodiment thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.

Summary:
A refuse collection device includes a tubular portion to which a bag mount is attached. The bag mount defines a passage. A cover is movably mounted to the bag mount for openably closing the passage. A flexible bag, such as a plastic bag, has a front opening fit over and releasably secured to the bag mount for receiving refuses through the passage. The bag is comprised of first and second sheets, each having a front edge folded over sections of the bag mount. The front edge of the first sheet forms a cut line dividing the front edge into two opposite free flaps for facilitating mounting the bag to the bag mount. A flap retainer is mounted to the tubular portion and is biased by a torsional spring to securely fix the flaps to the bag mount thereby preventing the flaps from arbitrarily moving within the passage and thus enhancing collection of refuses into the bag. The torsional spring has a small spring constant that is only sufficient to overcome inherent resiliency of the flaps for effectively retaining the flaps in position while causing no substantial interference with mounting and dismounting of the bag to and from the bag mount. An envelop is fit over the cover for protecting the cover from contamination by the collected refuses. A flexible strip extends from the bag, having a free end attached to the envelop whereby the bag and the envelop can be removed from the bag mount at the same time.