Down-locking pump

• US 4,369,899 A
• Filed: 11/18/1980
• Issued: 01/25/1983
• Est. Priority Date: 11/18/1980
• Status: Expired due to Term

• Current Assignee: Calmar Laser (Meadwestvaco Corporation)
• Original Assignee: Realex Corporation
• Inventors: Foster, Donald D., Magers, Wallace F.
• Primary Examiner(s): SKAGGS JR, H GRANT
• Application Number:
  US06/207,892
• Time in Patent Office: 798 Days
• Field of Search: 222/153, 222/321, 222/402.11, 222/402.14, 222/321, 222/384
• US Class Current: 222/153.13
• CPC Class Codes: B05B 11/106 in a retracted position, e.g. in an end-of-dispensing-stroke position
• CPC Class Codes: B67D 7/0211 with pump locking means

Abstract

When the plunger is fully depressed, radially projecting lugs carried by the plunger adjacent its normally upper end may be received within corresponding notches in a collar through which the plunger reciprocates, whereupon rotation of the plunger in a clockwise direction moves the lugs under overhanging shoulders of the collar so as to prevent extension of the plunger until it is intentionally unlocked from the collar. A total of three lugs are utilized so as to provide three-point, stabilized retention of the plunger in its locked-down condition, and one of the lugs and its corresponding notch is smaller than the other two so that the plunger can be locked only when it is in a certain, predetermined rotative position relative to the collar aligning the down-sized lug and notch. Each of the shoulders is provided with a lower, lug-engaging, inclined surface which bears against its corresponding lug with progressively increasing force for fluid-tight sealing purposes as the plunger is rotated into a fully locked condition, there being abutments associated with the shoulders blocking movement of the lugs beyond positions corresponding to the fully locked and rotated position of the plunger.

Claims

1. In a down-locking pump, the improvement comprising:

a tubular body having an inlet at one open end thereof and an annular collar at the opposite, open end thereof;

a valve operably associated with said inlet for opening and closing the same;

a tubular plunger telescopically and rotatively received by said collar for movement in opposite axial directions within the body through pumping strokes,

said plunger being operable, when fully depressed, to maintain said valve in a position sealably closing said inlet;

seal structure including cooperating portions on said collar and said plunger respectively and operable, when said plunger is fully depressed, to seal the interface between the collar and the plunger,

said cooperating portions of the seal structure, the collar, and the plunger all being constructed from the same material;

a plurality of generally radially outwardly projecting locking lugs carried by said plunger adjacent the normally outer end thereof;

a plurality of notches in said collar adapted to selectively receive said lugs of the plunger when the latter is in said fully depressed position;

a plurality of shoulders interspersed between said notches and disposed to restrictively overlie said lugs and prevent extension of the plunger when the lugs have been received in said notches and the plunger rotated relative to the collar,

said shoulders being provided with normally downwardly facing inclined surfaces disposed to bear against the normally upper extremities of said lugs with progressively increasing force as the plunger is rotated in one direction with the lugs disposed beneath the shoulders whereby to establish proper forcible interengagement between the portions of said seal structure and to properly maintain said inlet valve closed; and

limit means on said collar normally below said shoulders presenting a normally upwardly facing surface in spaced opposition to said downwardly facing surfaces of the shoulders for cooperating with the latter in traping said lugs against movement in either axial direction once the lugs have been locked beneath said shoulders to thereby absorb shock loading which would otherwise be transmitted to said seal portions,

the minimum spacing between said opposed traping surfaces of the collar being substantially the same as the thickness of said lugs in the axial direction.

2. In a pump as claimed in claim 1, wherein each of said shoulders is further provided with an abutment at one termination of said surface in position to block further rotation of the plunger in said one direction.

3. In a pump as claimed in claim 1, wherein said collar includes a generally cylindrical outer portion and a generally cylindrical inner portion spaced radially inwardly from said outer portion, said inner portion having an axial end extremity presenting said limit means.

4. In a pump as claimed in claim 3, wherein said portions are provided with bridging means integrally interconnecting the same at said end extremity.

5. In a pump as claimed in claim 1, wherein said lugs and said notches are so configured that the lugs may enter the notches only in a certain, predetermined rotative position of the plunger.

6. In a pump as claimed in claim 5, wherein two of said lugs and their corresponding notches are mutually identically configured, the third of said lugs and its corresponding notch being differently configured relative to said two lugs and notches.

7. In combination with a container having a lateral extremity and a top, a pump for dispensing product from the container comprising:

a plunger;

a collar guiding the plunger for reciprocation relative thereto and including means for attaching the pump to the top of the container;

a plurality of generally radially outwardly projecting lugs carried by said plunger adjacent the normally outer end thereof;

a plurality of notches in said collar adapted to selectively receive said lugs of the plunger when the latter is in said depressed position;

a plurality of shoulders interspersed between said notches and disposed to restrictively overlie said lugs and prevent extension of the plunger when the lugs have been received in said notches and the plunger rotated relative to the collar;

an abutment positioned adjacent one end of at least one of said shoulders respectively below the same and in spaced relationship to the notch corresponding therewith for limiting the extent of rotation of the plunger relative to the collar when the lugs are locked beneath said shoulders,

said attaching means including structure operable to permit said plunger and collar to be rotated as a unit relative to the container top in a direction pressing said lugs against said abutments; and

an elongated dispensing spout projecting laterally from the outer end of the plunger,

said spout being positionable with its outermost end disposed within the lateral extremity of the container when the plunger and collar are locked together for rotation whereby to facilitate packaging and shipping,

said spout, said plunger, said lugs, said notches and said abutments being so positioned relative to each other and to the lateral extremity of the container that upon unlocking rotation of the plunger from said disposition of the outer end of the spout within the lateral extremity of the container to a disposition realigning the lugs with their notches for an upstroke of the plunger, and then further rotation of the plunger once unlocked to a normal use position in which the outer end of the spout projects its greatest distance from and beyond said extremity of the container, said lugs are disposed out of alignment with their notches to reduce the chances of the lugs becoming unintentionally realigned with their notches during operation of the pump in said normal use position.