US 3848779 A
A dispensing cap construction comprising a threaded tubular cap body and a screw cap both of molded plastic composition. The body and cap have cooperable stop lugs one of which has a camming surface. When the cap is applied at the factory, it is screwed clockwise to the full-on, sealing position. Part way through the screwing-on, the lugs become engaged, and are forced past each other by a camming action. Thereafter the lugs constitute stops to halt the cap in the full-on sealing position, or in the partially unscrewed, dispensing position. The cap is thus held captive on the body, being turnable to various dispensing positions and to the full-on sealing position.
Claims available in
Description (OCR text may contain errors)
United States Patent 1191 Stull Nov. 19, 1974 CAPTIVE DISPENSING CAP CONSTRUCTION Morton B. Stull, 2132 81st St. Gulf, Marathon, Fla. 33050 Filed: Sept. 8, 1969 Appl. N0.: 855,971
US. Cl. 222/521 Int. Cl B67d 3/02 Field of Search 222/519, 520, 521, 499
References Cited UNITED STATES PATENTS 2/1951 Paulsen 222/499 l0/l962 Kubiliunas 5/1964 11/1965 3/ 1966 10/1968 3/1969 Primary ExaminerRobert B. Reeves Assistant Examiner-Thomas E. Kocovsky Attorney, Agent, or Firm-H. Gibner Lehmann; K. Gibner Lehmann [5 7] ABSTRACT A dispensing cap construction comprising a threaded tubular cap body and a screw cap both of molded plastic composition. The body and cap have cooperable stop lugs one of which has a camming surface. When the cap is appliedat the factory, it is screwed clockwise to the full-on, sealing position. Part way 5 Claims, 7 Drawing Figures Z 22 Z 24 i2 sc i 18 I 30 m 2% f 2 5 54 4 44 I 36 1- II 52 46 l6 CAPIIVE DISPENSING CAP CONSTRUCTION CROSS REFERENCES TO RELATED APPLICATIONS AND PATENTS Pat. No. 3,216,630 Pat. No. 3,319,843 Pat. No. 3,339,773 Pat. No. 3,351,249 Pat. No. 3,407,967 Pat. No. 3,406,880 Pat. No. 3,370,764
BACKGROUND This invention relates to dispensing screw cap structures, and more particularly to constructions of this type wherein the screw cap proper is held captive on the spout or body portion.
Heretofore, dispensing caps of the captive type involved either a construction where the cap was initially applied to the body part by mainly an axial movement involving stripping of the threads past each other, or a construction where annular detent beads were initially forced past each other and thereafter constituted the stop means. These prior caps performed satisfactorily in many circumstances, but usually were not suitable with glue or glue-like products since their action was generally impositive.
SUMMARY The above disadvantage of prior captive screw caps is obviated by the present invention, one object being the provision of an improved captive screw cap wherein the initial applying of the cap proper is done by the usual clockwise turning action, and wherein there are positive stops not only to limit the screwingon of the cap but also to prevent the complete unscrewing and removal of the cap. This is accomplished by a cap construction comprising a threaded tubular cap body and a screw cap both of molded plastic composition. The body and cap have cooperable stop lugs one of which has a camming surface. When the cap is applied at the factory, it is screwed clockwise to the fullon, sealing position. Part way through the screwing-on, the lugs become engaged and are forced past each other by a camming action. Thereafter the lugs constitute stops to halt the cap in the full-on sealing position, or in the partially unscrewed, dispensing position. The stop lugs normally have abutting engagement whereby the stop action is of a positive nature.
Other objects and features of the invention reside in the provision of an improved captive screw cap as above set forth, which is especially effective and reliable in its operation, simple in construction, involves few parts, and is inexpensive to produce.
Still other features and advantages will hereinafter appear.
In the drawings:
FIG. 1 is a side elevational view of the cap body part of the construction, with the screw cap part shown in axial section.
FIG. 2 is a top plan view of the body part.
FIG. 3 is a bottom plan view of the body part.
FIG. 4 is a side elevational view of the screw cap part of the construction.
FIG. 5 is a top plan view of the screw cap part.
FIG. 6 is an axial section of the screw cap part, taken on line 6-6 of FIG. 5.
FIG. 7 is a side elevational view of the cap construc tion with a portion of the cap part broken away. This view illustrates the interference and camming action between the stop lugs during assembly of the cap part to the body part.
Considering first FIGS. 1 and 7, the improved dispensing cap construction of the invention is seen to comprise a cap body part designated generally by the numeral 10, and a screw cap part designated generally by the numeral 12. The cap body part is of tubular configuration, being adapted for attachment to a container (not shown) as by means of internal screw threads 14 disposed in a lower portion 16. It will be understood that the portion 16 of the body part may be screwed onto the threaded neck of the container.
The body part 10 has a discharge spout portion 18 terminating at its upper or outer end in a stopper pin 20 which is supported by three webs 22 defining triangular openings 24 through which the product from the container can pass after traversing the spout portion. The screw cap part 12 has a central opening 26 in its tip to accommodate the stopper pin 20 when the cap is screwed down to its full-on position as shown in FIG. 1. A seal is thus effected by the pin 20, preventing leakage of the product from the cap construction. -The screw cap part 12 also has annular sealing surfaces 28, 29 arranged for tight engagement with a shoulder portion 30, 31 of the spout 18 to effect a seal below the triangular openings 24 of the spout.
The body part 10 and screw cap part 12 have a pair of mutually engageable portions comprising cooperable screw thread means 32, 34 respectively on said parts for moving the cap part axially as it is turned. The screw thread means comprises a helical thread element 32 of the buttress type, said thread element having working surfaces characterized by a relatively small slope or angle with respect to the axis of the cap construction. The arrangement is such that, as in the present case where there is a certain degree of yieldability of the parts, the thread elements may be stripped past each other by applying an excessive axial force to the cap part 12 in a direction tending to remove the same. However, the non-sloping shoulders of the buttress thread element prevent an opposite stripping, that is, prevent the cap part from being forcibly applied to the body part by purely axial movement.
In accordance with the present invention at least one of the parts of the cap construction, and preferably both said parts are constituted of resilient, yieldable plastic such as polyethylene or other suitable wellknown formulation whereby advantage is taken of the yieldability to effect a captive or stop action which prevents complete unscrewing and removal of the cap part 12. The cap part is normally held captive on the body part after it has been screwed on the latter to the full-on position or at least past an intermediate position representing the full-open or unstopped condition of the cap.
The helical thread elements 32, 34 function to effect downward (as viewed in FIGS. 1 and 7) axial movement of the cap part 12 as the latter is turned in a clockwise direction (as viewed from the top) and applied to the body part 10. However, if during such screwing-on operation of the cap part 12 it shouldencounter some momentary obstruction to its axial movement, one or both of the thread elements 32, 34 can yield as the cap part is momentarily halted axially. One
thread element will tend to ride up on the other, and when the obstruction to axial movement of the cap part ceases, the thread elements will tend to spring the cap part 12 downward or toward its full-on position as the elements restore to their initial, normal or non-yielding, non-deformed condition.
The body part has a second or additional thread element, comprising a cam track 36 provided around the base of the spout portion 18, said cam track being cooperative with an interior lug 38 provided within the bottom rim 40 of the cap part 12. The lug 38 rides on the cam track 36 and imparts a positive outward axial movement to the cap part as the latter is turned in unscrewing direction.
The cap and body parts have a second pair of mutually engageable portions, comprising cooperable stop lugs one of which is constituted as the lug 38. The second lug, disposed on the spout portion 18 of the body part, is designated 42 and is disposed at the high end of the cam track 36. The stop lug 42 has opposite surfaces 44, 46 which are respectively engageable with opposite surfaces 48, 50 of the stop lug 38. Also, in accordance with the invention, the surface 46 of the lug 42 has a camming portion 52 constituting a face which slopes with respect to the direction of movement of the lug 38 of the cap part 12. The cam surface 52 is adapted to be engaged by the stop lug 38 of the cap part 12 as the latter is screwed onto the body part 10, such engagement being illustrated in FIG. 7. The engagement with the sloping face 52 constitutes a momentary obstruction or impediment to the downward axial movement of the cap part 12 and in fact causes an opposite or slightly raising movement of the cap part as the turning of the latter is continued. During such reverse movement, the thread elements 32, 34 will yield, one element riding up an extent on the other as permitted by the slightly sloping engaged faces of the elements. Referring again to FIG. 7, as the clockwise turning movement of the cap part 12 is continued, the stop lug 38 thereof will be forced past the top of the lug 42 of the body part 10 and upon reaching the surface 44 of the lug 42 it will snap downward into a recess 36a constituted of the space immediately over the highest part (adjoining the stop lug 42) of the cam track 36, so as to engage the high portion of the cam track 36. This snapping downward of the lug 38 and cap part 12 whereby the lug 38 is freely received in said recess 36a above the highest part of the cam track 36, is due in part to the tendency for the deformed thread elements to resume the nonyielding or unsprung condition. Also, the equipment (not shown) which applies the screw cap 12 may have a spring action by which the cap part is yieldably urged downward as it is being screwed onto the body part 10.
Upon the lug 38 of the cap part being cammed past the lug 42 of the body part, the screwing-on movement of the cap part can be continued until it reaches the full-on position of FIG. 1.
'It will now be understood that as the consumer unscrews the cap part 12 to avail himself of the product, the lug 38 can be brought into engagement with the stop surface 44 of the lug 42, whereby further unscrewing of the cap part 12 will be prevented. For the full-on position of the cap part, the surface 48 of the lug 38 is engaged with the surface 46 of the lug 42, whereupon there exists positive stops defining not only the full-on position of the screw cap but also the full-open position of the same.
For different intermediate positions of the cap part 12, the extent of closing of the discharge opening 26 by the sealing pin 20 can be varied, thereby providing a degree of control of flow of the liquid product from the container.
It will now be understood from the forgoing that l have provided a novel and improved captive dispensing cap construction wherein the cap part is threaded onto the body part by a conventional screwing-on movement, and wherein after the cap part reaches its full-on position, it will be prevented and-held from complete removal by a positive stop. The unscrewed or dispensing position of the cap part 12 and also the full-on or sealing position of the part are determined by positiveaction stop lugs, and the cap part is held captive on the body part once it has been applied thereto and screwed past the full-open dispensing position.
Variations of the structures shown are possible without departing from the spirit of the invention.
1. A captive dispensing cap construction comprising, in combination:
a. a tubular body part adapted to be carried by a container and having a discharge spout,
b. a screw cap part carried by said body part and surrounding said discharge spout,
c. said cap and body parts having two pairs of mutually engageable portions,
d. one pair of mutually engageable portions comprising cooperable screw thread means respectively on said parts, for moving the cap part axially on the body part as the cap part is turned,
e. the other pair of mutually engageable portions comprising cooperable stop lugs respectively on the body and cap parts,
f. one set of surfaces of the lugs becoming engaged and acting in a manner to halt clockwise turning of the cap part in screwing-on direction as the cap part is screwed toward its full-on position on the body part,
g. another set of surfaces of the said lugs becoming engaged and halting the opposite, unscrewing, turning of the cap part as the latter is unscrewed through part of a revolution from said full-on position,
h. one of said stop lugs having a sloping face with respect to the other stop lug to facilitate bypass of the lugs as the cap part is screwed onto the body part,
i. at least one of said portions of the said one pair of the mutually engageable portions comprising the cooperable screw threads of the said parts being resilient and yieldable to enable the cap part to shift so that the stop lug on the cap part can be forced past the stop lug on the body part as the cap part is applied to the body part and screwed toward its full-on position,
j. one of said parts of the cap construction having a recess adjoining the stop lug thereof and in the path of movement of said other stop lug but disposed circumferentially past the stop lug it adjoins, so as to freely receive the other stop lug of the other part after the lugs have bypassed each other, thereby to enable the screw thread means to continue freely elements arranged to permit the cap part to be stripped off the body part under the influence of excessive axial force.
5. A cap construction as in claim 1, wherein:
a. the resilient screw thread means when yielding in response to turning of the cap part and interference between the said lugs, continues to shift the cap part axially toward its full-on position as said interference is terminated.