Abstract:
A cap with a supply stopper for use with ordinary containers comprising a detachable double cap, that is, an outer cap and an inner cap which is used as a supply cap having a supply opening and a supply stopper. By an engagement mechanism of the upper cap and the inner cap, when the upper cap is fastened, the supply stopper is firmly pressed against the supply opening so that the leakage of contents in the container during storage or transportation is completely prevented.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates in general to a cap for use with containers for fluids, and more particularly involves a screw cap with a liquid supply stopper for use with containers for fluid substances including powders. 
     In the conventional containers for liquids, such as liquid developers, other liquid chemicals and liquid fuels, an ordinary screw cap is often used during transportation and storage, and when the liquid in the container is used, the screw cap is exchanged with a cap having a liquid supply stopper. 
     The conventional cap having a liquid supply stopper comprises a cap with a liquid supply opening, and a stopper having a rod passing through the liquid supply opening and projecting out of the opening, the stopper being disposed inside the cap and in pressure contact with the opening when not in use so as to shut the opening tightly by spring means connecting a support member of the rod with a support member fixed inside the cap. 
     When the liquid in the container is used, the container with the cap having a liquid supply stopper is turned upside down and the projecting rod is pushed against the resilience of the spring means in the cap, for example, by pushing the top of the rod against the bottom of a receiving container so as to space the liquid supply stopper from the liquid supply opening. Thus, the liquid flows out through the liquid supply opening. 
     Therefore, two different types of caps, namely, an ordinary screw cap and a cap having a liquid supply stopper, are used in the conventional liquid container. 
     However, the ordinary screw cap is apt to be loosened by vibrations or changes in temperature and atmospheric pressure or the like during storage or transportation, in particular, during air transportation, causing leakage of the liquid. 
     Moreover, as mentioned previously, when the liquid in the container is used, the screw cap has to be exchanged with the cap having a liquid supply stopper. At that time, unexpected accidents are apt to occur, such as turning over the container, the liquid being scattered by the slightest shock, smearing the clothes of a person who handles the container. In particular, such accidents are very dangerous in case the liquid is corrosive. 
     In the case of the conventional cap for use with the containers for powders, the above mentioned problems occur likewise. 
     SUMMARY OF THE INVENTION 
     It is, therefore, an object of this invention to provide a cap having two functions as a screw cap which is not loosened during storage and transporation and as a cap having a supply stopper so as to obviate the inconveniences of using and exchanging two different types of caps for use with containers. 
     Another object of this invention is to provide a cap which ensures safety in storage, transportation and handling of containers. 
     According to the present invention, there is provided a cap comprising a double cap, that is, an outer cap and an inner cap, the inner cap having a function as a cap with a supply stopper, and in this invention, when the outer cap is fastened, the supply stopper is pressed firmly over the supply opening of the inner cap by the connecting mechanism which connects the inner cap and the outer cap so that the leakage of contents during storage or transportation is completely obviated, and when the contents are used, only by unfastening the outer cap, the contents can be used in the same manner as in the containers with the conventional cap having a supply stopper. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1-3 illustrate the first preferred embodiment according to the present invention. 
     FIG. 1 is a partially sectional view of an inner cap of the embodiment of this invention. 
     FIG. 2 is a cross-sectional view of an outer cap of the embodiment of this invention. 
     FIG. 3 is a cross-sectional view of the fitting condition of the outer cap and the inner cap of the embodiment of this invention. 
     FIGS. 4-6 illustrate the second preferred embodiment according to this invention. 
     FIG. 4 is a perspective view of an inner cap of the second embodiment of this invention. 
     FIG. 5 is a perspective view of an outer cap, partly in section, of the second embodiment of this invention. 
     FIG. 6 is a cross-sectional view of the fitting condition of the outer cap and the inner cap of the second embodiment of this invention. 
     FIG. 7 is a side view of a preferred supply stopper having a groove and a projecting member which can be used in any of the above mentioned embodiments according to the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 1-3 illustrate the first preferred embodiment according to the present invention. 
     FIG. 1 is a partially sectional view of an inner cap of the first embodiment of this invention. The inner cap 1 has a supply opening 2 in the center of the inner cap 1. Inside the inner cap 1 is fixed a support member 3, through which a rod 5 having a supply stopper 4 at one end thereof is passed. At the other end portion of the rod 5 is fixed a disc 6. Spring means 7 is connected between the support member 3 and the disc 6 so that the supply stopper 4 is pressed tightly against the supply opening 2 by the resilience of spring means 7. 
     The numeral 8 is a screw fitting portion of the inner cap 1, which fits in the screw fitting portion 12 of an outer cap 11 in FIG. 2. The numeral 9 is a screw fitting portion of the inner cap 1 which fits in the screw fitting portion of a container in general use. 
     The numeral 10 is a portion where the supply opening 2 and the supply stopper 4 are brought into close contact with each other. 
     FIG. 2 is a cross-sectional view of the outer cap 11 of the first embodiment of this invention. 
     The outer cap 11 is fastened at the screw fitting portion 12 and a screw fitting portion 8 of the inner cap 1. 
     At the inside center of the outer cap 11 is provided a screw socket 13. The pitch of the screw thread of the screw socket 13 is a little greater than that of the screw threads of the screw fitting portions 12 and 8, respectively, of the outer cap 11 and the inner cap 1. 
     On the outer cap 11 is provided a nonskid 14 to prevent skidding when the outer cap 11 is screwed. 
     The operation mechanism of the inner cap 1 and the outer cap 11 is as follows: 
     As shown in FIG. 3, the inner cap 1 is screwed at the screw fitting portion 9 of the supply opening 2 of an ordinary container. At this time, the supply stopper 4 is being tightly pressed against the close contact portion 10 of the supply opening 2 by the resilience of spring means 7 connected between the disc 6 fixed at the end portion of the rod 5 and the support member 3. Then, the outer cap 11 is screwed so that the screw fitting portion 12 is fitted in the screw fitting portion 8 of the inner cap 1. At this time, the disc 6 fixed at the rod 5 is screwed into the screw socket 13. As the outer cap 11 is screwed, the disc 6 is screwed into the screw socket 13 as well. Therefore, the rod 5 is pulled outwards by the disc 6 and accordingly, the supply stopper 4 fixed at the lower end of the rod 5 is also pulled in the same direction, resulting in that the supply stopper 4 is brought into closer contact with the close contact portion 10. 
     Since the pitch of the screw thread of the screw socket 13 is greater than that of the screw threads of the screw fitting portions 12 and 8, the supply stopper 4 is brought into much closer contact with the close contact portion 10 as the outer cap 11 is screwed. 
     When the contents in the container are used, the outer cap 11 is unscrewed and detached and the container with the inner cap 1 is turned upside down and the top of the projecting rod 5 is pushed against the resilience of spring means 7 in the inner direction of the container, for instance, by pushing the rod 5 against the bottom of a receiving container. Thus, the supply stopper 4 is unfitted from the supply opening 2 and thus the content flows out through the liquid supply opening 2. 
     FIGS. 4-6 illustrate the second preferred embodiment according to the present invention. 
     FIG. 4 is a perspective view of an inner cap 1&#39; with a supply stopper 4&#39;. The inner cap 1&#39; has a supply opening 2&#39; in the center of the inner cap 1&#39;. Inside the inner cap 1&#39; is fixed a support member 3&#39;, through which a rod 5&#39; having the supply stopper 4&#39; at one end thereof is passed. At the other end of the rod 5&#39; is provided a fixing head 15. Spring means 7&#39; is connected between the support member 3&#39; and the fixing head 15 in the manner that the resilience of spring means 7&#39; is generated. The fixing head 15 is conic and has a pair of projecting parts at both sides thereof. 
     The axially outer wall of the inner cap 1&#39; has an externally projecting, circumferentially extending, axially inclined guide tooth 8&#39; which engages a corresponding guide tooth inside the outer cap 11&#39;. In the second embodiment, the outer cap 11&#39; fixedly engages with the inner cap 1&#39; through the guide tooth by the turn of 90 degrees. The axial incline of the guide teeth acts to draw the outer cap 11&#39; axially inwardly relative to the inner cap 1&#39; when the outer cap 11&#39; is turned the 90 degrees. 
     FIG. 5 shows the outer cap 11&#39;. Inside the outer cap 11&#39; is provided a shelf 16. In the center of the shelf 16 is a hole 17 which permits passing of the fixing head 15. 
     FIG. 6 is a cross-sectional view of the fitting condition of the inner cap 1&#39; and the outer cap 11&#39;. 
     In FIGS. 4-6, the identical parts are given the identical numerals. 
     In this embodiment, when the outer cap 11&#39; is put on the inner cap 1&#39;, the fixing head 15 of the inner cap 1&#39; appears from the shelf 16, passing through the hole 17 of the outer cap 11&#39;. Under such condition, the outer cap 11&#39; is turned by 90  degrees. Then, the outer cap 11&#39; is firmly fitted with the inner cap 1&#39; by the engagement of the guide tooth 8&#39; with the corresponding guide tooth inside the outer cap 11&#39;. 
     At this time, the hole 17 of the shelf 16 is also turned by 90 degrees. This results in that a pair of the projecting parts of the fixing head 15 are caught by the circular edges of the hole 17 and at the same time, the fixing head 15 is pulled outwards because the axially outer wall of the inner cap 1&#39; pushes the shelf 16 axially outwardly as the guide teeth draw the outer cap 11&#39; axially inwardly relative to the axially outer wall of the inner cap 1&#39;. 
     Therefore, the supply stopper 4&#39; is also pulled outwards through the rod 5&#39; so that the supply stopper 4&#39; is more closely fitted into the close contact portion 10&#39; of the supply opening 2&#39;. 
     FIG. 7 is a front view of a preferred supply stopper which can be used in any of the above mentioned embodiments according to the present invention. 
     At the lower outside portion of the supply stopper are provided a groove 18 and a projecting member 19. Inside a container are also provided a projecting member and a groove, which fit in the groove 18 and the projecting member 19, respectively. 
     When this supply stopper is incorporated in the first or second embodiment, and the rod 5 in FIG. 1 or the rod 5&#39; in FIG. 4 is pulled outwards by screwing the outer cap, with these grooves and projecting members fitted, the pulling action of the rod or the fixing head can be ensured without rotating the rod in FIG. 1 or FIG. 4.