Pump unit

A pump unit is adapted for attachment to a liquid container having a liquid discharge opening bounded by an annular rim formed with an external screw thread by providing the housing of the pump unit with an annular mounting flange and employing a two-part cap rotatably coupled to the mounting flange to threadably couple the pump unit to the screw thread of the container rim. The parts of the cap are hinge connected to allow for swinging movement of the parts between remote and adjacent positions as an incident to which the cap is coupled to the mounting flange and provided with a latch for retaining the parts in their adjacent position.

BACKGROUND OF THE INVENTION 
It is known to provide a manually operable compressed air pump unit to 
dispense liquid from a container, wherein such unit includes a pump barrel 
slidably receiving a manually operable plunger controlling entry of liquid 
from the container into a pump chamber via a first valve and discharge of 
liquid from the pump chamber into a reservoir via a second valve for 
subsequent discharge from the reservoir via a tube fitted with a manually 
operable spray control valve, as evidenced for instance by U.S. Pat. Nos. 
1,059,373; 1,986,756; and 2,281,142. 
It is also known to removably attach manually operable pumps of various 
sorts to liquid containers by fitting these pumps with caps intended to 
threadably engage with external screw threads carried by mounting rims 
bounding discharge openings of the containers. A drawback of known pump 
unit constructions of this general type is that a different pump unit is 
required for differently sized containers having unique screw thread 
sizes/shapes. 
SUMMARY OF THE INVENTION 
The present invention is generally directed towards an improved pump unit 
for use in dispensing liquid from a container to which the unit is 
attached by a screw threaded cap, and more particularly to a pump unit 
where its principal parts may be fabricated as a common subassembly 
selectively attached to a series of liquid containers having mounting 
screw threads of differing size and/or thread design by selectively 
fitting the subassembly with a series of separately formed caps having 
mounting threads corresponding in size and/or thread design to those of 
the series of containers. 
In a preferred form of the invention, the common subassembly of the pump 
unit includes a housing fitted with first mounting means conveniently in 
the form of an annular mounting rib, and the cap includes two parts having 
arculate recesses, which cooperate to define an annular recess for loosely 
receiving the mounting rib, such as will permit rotation of the cap 
relative to the housing when the cap parts are maintained adjacent one 
another. The cap parts are also formed with arculate thread portions, 
which cooperate, when the cap parts are maintained adjacent one another, 
to define a screw thread adapted for threaded engagement with the mounting 
screw threads of a given liquid container. 
Preferably, the cap parts are connected together by a hinge for swinging 
movement between a remote position and an adjacent position in which the 
cap parts may be maintained by a latch. 
Further, in accordance with the present invention, the pump unit is formed 
with a unique housing consisting of two housing parts which define or 
cooperate to define all elements of the pump subassembly except for its 
movable parts consisting of fluid flow control valves and a 
manually-operated pump plunger or piston.

DETAILED DESCRIPTION 
Reference is first made to FIGS. 1 and 2, wherein a pump unit formed in 
accordance with the present invention is generally designated as 10 and 
shown as being adapted for use in dispensing liquid from a suitable 
container 12 having a liquid discharge opening 14 bounded by an annular 
mounting rim 16 formed with an external screw thread 18. The construction 
of container 12 may be conventional in all respects. 
Pump unit 10 includes a pump housing 20 formed from first and second 
housing parts 20a and 20b, respectively. Housing part 20a is shown in FIG. 
2 as including a first generally cup-shaped portion having an annular side 
wall 22 joined at one end to an end wall 24 having a centrally-located 
through opening 26 and defining at an opposite or free end a first annular 
mounting rim 28; and a cylindrical pump barrel 30 having one end joined to 
end wall 24 in alignment with opening 26 and defining at an opposite or 
free end a second annular mounting rim 32. Pump barrel 30 is shown as 
bounding a cylindrical pumping chamber 34 aligned with end wall opening 26 
and as defining one or more radially through passageways 36 disposed 
adjacent mounting rim 32 for flow communication with pumping chamber 34. 
Preferably, end wall 24 is formed with an annular mounting rim 38 arranged 
concentrically of opening 26. 
Housing part 20b is also shown in FIG. 2 as including a second generally 
cup-shaped portion having an annular side wall 40 joined at one end to a 
base portion 42 externally sized to be removably inserted into a container 
12 through discharge opening 14 and defining at an opposite end a third 
annular mounting rim 44 having an annular mounting recess 46 sized and 
shaped for fluid sealing engagement with first annular mounting rim 28. 
Housing parts 20a and 20b may be considered as having first or adjacent 
connected ends defined by mounting rims 28 and 44, and second or remote 
ends defined by end wall 24 and base portion 42. 
Base portion 42 additionally defines a fourth annular mounting means, such 
as a tubular recess 48 arranged to open through an upper surface of the 
base portion and being sized and shaped for fluid sealing engagement with 
second annular mounting rim 32, a fluid passageway 50 for placing pumping 
chamber 34 in flow communication with the interior of container 12, and a 
first mounting means preferably in the form of an annular, radially 
outwardly projecting rib 52. Passageway 50 terminates in a barbed coupling 
54, which extends from a lower surface of base portion 42 and serves to 
mount an upper end of a tube 56 extending from base 42 to a point adjacent 
a bottom wall 12a of container 12 in order to insure essentially complete 
discharge of the contents from the interior 12b of such container. 
As will be apparent from viewing FIG. 2, housing part 20a and housing part 
20b arranged upwardly of base portion 42 cooperate to define an enlarged 
reservoir 58 disposed concentrically outwardly of pump barrel 30. Thus, 
housing part 20a, and also the upper part of housing part 20b in the 
construction shown in the drawings, are required to have a substantially 
larger diameter than base portion 42, such that they cannot fit within 
container opening 14. Preferably, the housing parts are each formed of 
molded plastic material, and permanently joined to one another by suitable 
means, such as by an adhesive. 
Pumping chamber 34 is arranged for flow communication with the interior 12b 
of container 12 via passageway 50 under the control of a first one way 
valve including a ball 60 arranged to engage seat 62 and with reservoir 54 
via passageways 36 under the control of a second one way valve including 
an annular, resiliently deformable ring or band 64. The extent of movement 
of ball 60 away from seat 62 is limited by a suitable abutment pin 66. 
A manually operated plunger or piston 70 is slidably associated with pump 
barrel 30, and includes a piston head 72 slidably supported in 
fluid-sealed relationship within the pump barrel, a manually operated 
handle 74 arranged exteriorly of pump housing 20 and a piston rod 76 
having its opposite ends connected to the piston head and the pump handle. 
Piston rod 76 may be guided during reciprocation thereof within pump 
barrel 30 by an apertured disc or guide ring 78 peripherally located by 
mounting rim 38. The described elements of plunger 70 may conveniently be 
formed from molded plastic materials. 
An outlet or discharge tube 80 is connected to reservoir 58 by a barbed 
coupling 82 molded-formed integrally with one or the other of housing 
parts 20a or 20b. The discharge end, not shown, of tube 80 may be 
connected, as desired, to a known manually-controlled spray nozzle, also 
not shown. 
The above-described construction forms a common subassembly, which may be 
selectively attached to a series of containers having mounting screw 
threads 18 of differing size and/or thread design or shape by providing 
the subassembly with a series of separately formed container caps or 
closures 84, which have mounting screw threads 86 corresponding in size 
and/or thread design or shape to screw threads 18 and a common means 
adapted for individually mounting the caps on subassembly rib 52. 
One cap 84 is shown for example in FIGS. 2 and 4 as being formed with a 
first part 92a and a second part 92b having first or adjacent edges or 
surfaces 94a and 94b connected to one another by a hinge device 96 and 
second or remote edges or surfaces 98a and 98b adapted to be fixed in an 
adjacent relationship by a suitable latch defined as by a convex locking 
rib 100a sized for receipt within a concave locking slot 100b. Cap parts 
92a and 92b are also formed with arculate mounting recess portions 102a 
and 102b, and arculate screw threaded portions 86a and 86b, as best shown 
in FIGS. 2 and 4. Preferably, cap 84 is of integrally formed, molded 
plastic construction, wherein locking rib 100a and locking slot 100b are 
sized and resiliently deformable sufficiently to permit the rib and slot 
to be snap-fitted together for purposes of cooperation with hinge device 
96 to maintain cap parts 92a and 92b adjacent one another, as shown in 
FIG. 1. 
Hinge device 96 serves to couple cap parts 92a and 92b for swinging 
movement between their relatively remote or open position shown in FIGS. 2 
and 4 into their adjacently disposed position shown in FIG. 1. In this 
latter position, mounting recess portions 102a and 102b cooperate to 
define an annular recess, not shown, which is sized to loosely receive 
annular mounting flange 52, thereby to connect or couple cap 84 to housing 
20 for free rotational movement about an axis, not shown, extending 
lengthwise of housing parts 20a and 20b. Also in this latter position, 
screw threaded portions 86a and 86b cooperate to define an internal screw 
thread 86 sized/shaped to threadably engage with screw thread 18 for 
purposes of removably mounting cap 84, and thus the whole of pump unit 10, 
on container 12 with housing first portion 20b inserted inwardly thereof 
through opening 14. Unit 10 may be fitted with a suitable resiliently 
deformable sealing ring 106 to facilitate fluid sealing of cap 84 relative 
to container mounting rim 16. 
As will be apparent, once cap 84 is threadably coupled to container rim 16, 
a user may dispense liquid from container 12 by first manipulating handle 
74 to extend plunger 70, i.e. move same outwardly relative to pump barrel 
30 in a direction away from its inserted position shown in FIG. 2, in 
order to produce a partial vacuum within inner end of pumping chamber 34 
which is sufficient to lift ball valve 60 from closing engagement with 
valve seat 62 and then draw liquid contents of the container upwardly into 
the pumping chamber. Thereafter, manipulation of handle 74 to purposes of 
returning plunger 70 to its initial position will first serve to return 
ball valve 60 to its closed or seated position and then force liquid 
previously drawn into pumping chamber 34 to flow into reservoir 58 past 
second valve 64, with the latter tending to return to its closed or seated 
position relative to outlet opening 36 upon arrival of the plunger in its 
initial position. Repeated strokes of plunger 70 will serve to charge or 
fill reservoir 58 to a point at which air trapper therein will be 
compressed sufficiently to expel liquid through conduit 80 upon opening of 
a suitable hand operated discharge flow control valve, not shown, 
associated with such conduit. The discharge control valve may be of the 
type with which commercially available, manually operably compressed air 
garden type sprayers are typically fitted. 
As previously indicated, an advantage of the illustrated construction of 
pump unit 10 is that housing portions 20a and 20b, and plunger 70 may be 
assembled as a pump unit subassembly, which can be selectively employed to 
dispense liquid from a series of liquid containers having differently 
sized/shaped screw threads by the expedient of providing a series of caps 
84 having appropriately sized/shaped internal screw threads and a common 
or like sized annular mounting recess for selectively mounting the caps 
one at a time on mounting flange 52. Fabrication of this series of caps is 
facilitated by employing a common or basic mold fitted with a series of 
removable inserts required to produce caps having desired size/shape 
thread configurations. 
As shown in the drawings, base 42 of housing portion 20b is required to be 
transversely sized so that it may be freely inserted through the smallest 
diameter opening 14 of a series of liquid containers 12 with which pump 
unit 10 is intended to be employed. It will also be understood that the 
length of base 42, as measured between its lower end and mounting flange 
52, is limited by the requirement that such lower end be spaced 
sufficiently from container bottom wall 12a so as to allow for flow of 
liquid inwardly of pump chamber 34 through tube 56, when cap 84 is fixed 
to mounting rim 16 of the shortest container of the series of containers 
with which the pump unit is intended to be employed.