Abstract:
A locking means for a fixing band of diving mask which can fasten or release the fixing band as a fastening member to which one end of the fixing band is connected is inserted into or removed from a mask frame by one action. The locking means comprises two main portions: holders provided at the both sides of a mask frame integrally formed with a face fitting member of the diving mask, and fastening member formed in a taper shape, having three triangle pawls integrally formed with the fastening member. The three triangle pawls are so arranged as to become higher in order, so that the fastening member be gradually tightened owing to the triangle pawls as the fastening member is moved forwards. The locking means in accordance with this invention is particularly useful in a fixing band of a diving mask.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to a diving mask. More particularly, the present invention relates to a locking means for releasably fastening the fixing band of a diving mask, to which one end of the fixing band, is connected by insertion at its ends into the diving mask frame in one action. 
     2. Description of the Prior Art 
     In conventional diving masks, a chrome-steel fastening member is inserted into a holder provided at the side surface of a mask frame and placed in its locking condition thereby, and a portion of a fixing band is connected to the fastening member. Thus, the end portion of the fixing band may become entangled with seaweeds or knock against bars or pickets during diving, which can result in serious trouble. Furthermore, the manufacturing cost of such a fastening member per se is relatively high. 
     SUMMARY OF THE INVENTION 
     With these problems in mind, therefore, it is the primary object of the present invention to provide a locking means for a fixing band of a diving mask which can provide a fastening member manufactured at low cost. The fastening member is housed in the mask frame of the mask so as to protect the fastening member from damage and from entanglement with seaweeds. 
     Another object of the present invention is to provide a locking means for a fixing band of a diving mask which is designed so that the fixing band can be fastened or unfastened in one action. 
     As will be apparent to persons skilled in the art, the apparatus of the present invention may also be used with face masks for other purposes, e.g., for skiers, machinists and the like. 
     To achieve these objects, the locking means according to the present invention comprises holders, provided at both side surfaces of a mask frame integrally formed with a face fitting member, and fastening members each formed in a tapered shape for connecting to a fixing band which at it ends can be insertedly housed in each of the holders. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features and advantages of the locking means for a fixing band of a diving mask according to the present invention, over the prior-art locking devices or means, will be more clearly appreciated from the following description of the preferred embodiments of the invention, taken in conjunction with the accompanying drawings in which like reference numerals designate the same or similar elements or sections throughout the figures thereof. 
     FIG. 1 is a plan view showing essential parts of a diving mask which employs the present invention; 
     FIG. 2 is an elevational view of the diving mask of FIG. 1; 
     FIG. 3 is a sectional view taken along the line III--III in FIG. 2 showing the fastened condition of the fixing band at the right side of the figure and the unfastened condition of the fixing band at the left side therein, respectively; 
     FIG. 4 is a sectional view taken along the line IV--IV in FIG. 2; 
     FIG. 5 is a side view showing the right side of FIG. 2; 
     FIG. 6 is a side elevational view showing the fastening member; 
     FIG. 7 is a sectional view taken along the line VII--VII in FIG. 6; and 
     FIG. 8 is an end elevational view showing the fastening members of FIG. 6. 
     FIGS. 9 to 11 show steps in the process of moving the fastening member with the fixing band of the diving mask to fasten the fixing band in the holder. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an embodiment of the present invention will be explained with reference to the accompanying drawings. 
     Referring to FIGS. 1 to 5, there is shown a diving mask in which an embodiment of the present invention is employed. In the drawings, the reference numeral 1 denotes a face fitting member made of synthetic resin, rubber or the like. The most forward end of the face fitting member 1 (corresponding to the top end in FIG. 3, or the right end in FIG. 4) is formed to have a recessed groove 1a having a channel shape section. A strong and transparent glass plate 2 is fitted and fixed therein. A mask frame 3 is integrally fitted on the outer surface of the face fitting member 1 along the fringe of the glass plate 2 held therein. The mask frame 3 is integrally formed, with holders 3a and 3b substantially at the center of the two side surfaces (left and right) thereof. Hereinafter, the explanation will focus on only the holder 3a because the holder 3b is constructed in the same manner. Thus, the reference numerals of the holder 3a shall also denote the corresponding parts of the holder 3b. 
     The holder 3a seen most clearly in FIGS. 9-11 is formed in the shape of a housing which is constructed in such manner that a recessed end 3a 1  is formed in the most front end of the inside thereof and an opening O, having a rectangular shape, formed substantially at the center in the outer side surface of the holder 3a. This is shown most clearly in FIGS. 5 and 9. Further, the interior space of the holder 3a tapers off toward the front end as shown in FIG. 3. 
     Referring to FIG. 6, there is shown an embodiment of a fastening member 5 which can fit into the holder 3a. The fastening member 5 is made of synthetic resin so as to be highly flexible. The detailed configuration of the fastening member 5 is shown in FIGS. 6 to 8. That is, the rear end 6 (shaped as a pawl at the right end in FIGS. 6 and 7) of the fastening member 5 comprises a band bar 7, a locking member 10 and a tongue 11. There is a rectangular space 8, defined between the end pawl 6 and the band bar 7, and a substantially U-shaped space 9 defined between the band bar 7 and the locking member 10, as shown in FIG. 6. 
     The overall shape of the fastening member 5 is so tapered as to be similar to the internally tapered shape of the holder 3a as shown in FIG. 7. Thus, the tongue 11 of the fastening member 5 can fit the recessed end 3a 1  of the holder 3a, and the locking member 10 can engage with the rectangular opening O when the fastening member 5 is completely inserted in the holder 3a. The length of the fastening member 5 is shorter than that of the holder 3a, so that the fastening member 5 can be covered with the holder 3a except for the end pawl 6, as shown in FIG. 5. The locking member 10 is fixed only at the front end thereof, so that the locking member 10 can move like a plate spring as indicated by the direction of arrow D shown in FIG. 7. Further, the locking member 10 is formed with a front projection 13, three triangle pawls X, Y, and Z and a rear edge 12, as best shown in FIG. 6. The three triangle pawls X, Y and Z are so arranged as to become higher in this order, as shown in FIGS. 7, 9, 10 and 11, so that the fastening member 5 is threreby gradually tightened as it is moved forward. 
     A fixing band 15 is formed with a plurality of projections 16 at regular intervals on one side surface in the vicinity of each end thereof, as best shown in FIGS. 9-11. The fixing band 15 is so wound around the bar 7 as to engage the projections 16 in order to prevent the fixing band 15 from slipping off the bar 7. 
     The operation of the locking means, constructed as described above, will be explained as follows, and is best understood by reference to FIGS. 3 and 9-11. The fastening member 5 connected to the fixing band 15 is inserted in the holder 3a so that the front projection 13 engages with a holding edge 4 of the opening O. This state is shown by the left side holder 3a as shown in FIGS. 3 and 9. Further, as the fastening member 5 is moved forwards (towards the glass plate 2), the pawls X, Y and Z engage with the holding edge 4, each clicking more audibly in this order. The fastening member 5 is gradually tightened owing to the triangle pawls X, Y and Z as the fastening member 5 is moved forwards. Finally, when the tongue 11 of the fastening member 5 contacts the recessed end 3a 1  of the holder 3a, the rear edge 12 of the locking member 10 engages with the holding edge 4 and the end pawl 6 contacts the end of the holder 3a. This locked state is shown in the right side holder 3b in FIGS. 3, 5 and 9. In this locked state, the fastening member 5 is completely housed in the holder 3a (likewise 3b on the other side) and the fixing band 15 is kept fastened within the holder 3a. The triangle pawls X, Y and Z of the locking member 10 appear invisible through the opening O of the holder 3a. 
     In order to unlock the fastening member 5 from the holder 3a, the locking member 10 is depressed as indicated by the arrow 17 shown in FIG. 3. The rear edge 12 of the locking member 10 is released from the engagement with the holding edge 4 of the opening O in an instant. The fastening member 5 is moved backwards and the front projection 13 engages with the holding edge 4 of the opening O as shown in the left side holder 3a in FIG. 3. According to this engagement between the front projection 13 and the holding edge 4, it is possible to prevent the fastening member 5 from unnecessarily slipping out of the holder 3a. Then the fastening member 5 can be smoothly released from the holder 3a by depressing the front projection 13. 
     In addition to the above explanations, FIGS. 9 to 11 show the successive steps in engaging the fastening member, with the fixing band of the diving mask mask, in the holder to be fastened. In this process, the fastening member is gradually tightened owing to the triangle pawls as the fastening member is moved forward because the three triangle pawls X, Y and Z are so arranged as to become higher in this order. In FIG. 9, although the front projection is engaging with the holding edge 4, the first pawl X has not yet been engaged with the holding edge 4, so that it is possible to adjust the fixing band in that status. In the status shown in FIG. 10, it is more difficult to adjust the fixing band. Finally, in the status as shown in FIG. 11, the fixing band is completely fastened, and cannot be pulled out from the fastening member and diving mask. 
     As explained above, the locking means for the fixing band of diving mask comprises holders provided at both side surfaces of the mask frame, and fastening members, each formed in a tapered shape like a fan slightly unfolded, for connecting to the fixing band, which can be insertedly housed in each of the two holders. The fastening member connected to the fixing band near each of its ends is so designed as to be covered by the holder when the fastening member is fully inserted into each of the holders. Accordingly, the fastening member can be free from damage due to knocking against objects such as bars, and will be free of entanglement with seaweeds while the diving mask is used in the sea. Furthermore, the fastening member except for the end pawl is completely covered by the holder so that the overall appearance of the diving mask will be improved. Accordingly, the triangle pawls formed on the fastening member, appearing through the rectangular opening of the holder, not only assist the fastening function but also improve the design. The interiors of the holders, like the fastening members, are tapered in shapes to match each other so that the engagement and disengagement therebetween can be smoothly and exactly carried out. That is, the fixing band can be completely fastened or released by one action. Since the fastening member is made of synthetic resin, it can be manufactured at a lower cost in comparison with one made of chrome-steel. Also, a fastening member made of synthetic resin is not heavy and fits to the fixing band so that the fastening member does not slip off from the fixing band even when the fastening member is kept unlocked with respect to the holder. 
     It is further to be understood by those skilled in the art that the foregoing description is only of a preferred embodiment of the present invention and that various changes and modifications may be made without departing from the spirit and scope thereof.