2. Background of the Invention
[0001] The present invention relates to a spray pump improved to permit the fixing and holding
of nozzle port of a spray head at a position determined beforehand optimumly from
the requirement by the construction of the pump, as well as from the view point concerning
the advertising design on the surface of the container.
[0002] In the spray containers having spray pumps, it is preferred and necessary from the
view point of the construction of the pump structure that the nozzle port of the spray
head is directed in the same direction as the bend of the suction pipe suspended from
the lower end of the pump structure towards the bottom of the container. On the other
hand, since the name of the good and an advertising design are placed on the front
side of the outer surface of the spray container, it is necessary that the nozzle
port of the spray head is directed forwardly so that the spray may made in the same
direction as the display of the goods name and the advertising design.
[0003] Usually, the connection between the spray head and the valve stem is made through
a friction fitting engagement between the outer periphery of the upper end of the
valve stem and a bore of a rather large diameter formed in the lower end of the spray
head in communication with a vertical passage formed in the spray head. Since this
friction fitting engagement is not so tight, it is often experienced that an unintentional
relative rotation is caused between the spray head and the valve stem during the use.
An inadequate use of the spray container impairs the performance of the pump seriously
or make the pump inoperative, even though there is no defect in the pump structure.
This cannot be expected by the manufacturer. For instance, the rotation of the valve
stem within the cylinder may occur however the connection between the spray head and
the valve stem may be made tight. In such a case, one end of the valve stem is ground
by the keen edge of the coiled spring mounted on the bottom of the cylinder. In consequence,
the orifice is often clogged with the ground powder of the material of the valve stem.
In addition, the operation for depressing the spray head is unstabilized due to a
comparatively short length of fitting between the spray head and the valve stem.
[0004] Thus, in the spray container having a spray pump, it is desirable that the optimum
inital set condition given by the manufacturer is maintained over the period of use
of the spray container, by avoiding the unintentional relative rotation between the
valve stem and the spray head.
[0005] Under this circumstance, the present invention aims at providing a spray pump which
can fix and hold the spray nozzle port of the spray head at the correct position.
3. Summary of the Invention
[0006] It is, therefore, an object of the invention to provide a spray pump in which the
vertical upward and downward movement of the spray head is guided correctly in such
a manner as to avoid any unintentional rotation of the spray head with respect to
a stationary cap attached to the neck of the liquid container.
[0007] To this end, according to the invention, there is provided a spray pump comprising
a fitting projection formed in one of the ceiling surface of the stationary cap and
the opposing lower end surface of the spray head, and a fitting recess formed in the
other of these surfaces, one of these fitting surfaces being provided with a rotation-preventing
rib or the like protrusion while the other has a slit for guiding the protrusion,
the fitting engagement between the spray head and the stationary cap being made beforehand
when the spray head is fixed to the plunger.
4. Brief Description of the Drawings
[0008]
Fig. 1 is a vertical sectional view of a portion of a spray pump with the spray head
positioned at the upper end of the stroke;
Fig. 2 is a sectional view taken along the line II-II of Fig. 1;
Fig. 3 is a vertical sectional view of a portion of the pump structure of another
embodiment having a different type of rotation prevention means;
Fig. 4 is a cross-sectional view taken along the line IV-IV of Fig. 3;
Fig. 5 is a vertical sectional view of a portion of spray pump of still another embodiment
having a different type of rotation prevention means; and
Fig. 6 is a sectional view taken along the line V-V of Fig. 5.
5. Description of the Preferred Embodiments
[0009] Preferred embodiments of the invention will be explained hereinunder with reference
to the accompanying drawings.
[0010] Fig. 1 is a sectional side elevational view of a pump structure showing a spray head
and a stationary cap. The stationary cap 1 has a ceiling plate la and an annular peripheral
wall lb suspending downwardly from the periphery of the ceiling plate la so as to
form a downwardly opening fitting recess 2. Screw threads are formed in the inner
peripheral surface of the recess 2 so that the stationary cap 1 can be freely screwed
onto and out of the outer periphery of a neck portion of the spray container. A pump
cylinder 3 has a flange 3a which contacts at its upper surface with the lower surface
of the ceiling plate la. The pump cylinder 3 is made to fit in the recess 2 to suspend
downwardly therefrom. The arrangement is such that, when the cap 1 is mounted on the
neck of the container, the lower side of the flange 3a is born by the upper end of
the neck. As is well known, the pump cylinder 3 accomodates a plunger 4 having a piston
and a coiled spring supported by the bottom of the cylinder 3. The cylinder 3 is provided
with valves at portions thereof adjacent to the plunger and the suction pipe. These
parts are assembled in such a manner that, as the plunger 4 is moved up and down within
the cylinder by the manual force and the force of the coiled spring, the valves are
opened and closed alternatingly to discharge the content liquid.
[0011] The upper end portion of the plunger 4 projects upwardly through the central bore
lc of the ceiling plate la by a height which is determined in view of the necessity
for the fitting to the spray head and the downward stroke. An inner cylinder 5 and
an outer cylinder 6 protrude from the ceiling plate la as a unit with the latter,
concentrically with the central bore lc. An inner annular recess 7 provided in the
inner cylinder surrounds the plunger 4 protruding through the central bore lc so as
to open upwardly with the bottom thereof constituted by the ceiling plate. On the
other hand, an outer annular recess 8 is formed between the inner cylinder 5 and the
outer cylinder 6 so as to open upwardly with the bottom thereof constituted by the
ceiling plate. A reference numeral 9 designates a fitting surface formed on the outer
periphery of the inner cylinder 5 and adapted to fit in the spray head 10. Ribs 11
of a prdetermined height is formed on the fitting surface 9 so as to extend in the
axial direction. Although the described embodiment employs 3 (three) ribs 11 arranged
at a constant circumferential pitch, it is possible to use only one rib 11. Each rib
11 may have the form of a small projection.
[0012] As is well known, the spray head 10 is provided therein with a discharge passage
consisting of a vertical bore 12, a horizontal bore 13 and a nozzle 14 provided on
the end of the horizontal bore 13. The spray head 10 is further provided at its lower
end with a fitting bore 15 of a rather large diameter adapted to fit around and receive
the upper end of the plunger 4 so as to be fixed and connected to the plunger 4. The
fitting bore 15 is in communication with the vertical bore 12. The spray head 10 is
provided on the lower end thereof with a convexity or concavity complementary to the
shape of the upper surface of the stationary cap 1. More specifically, the spray head
is provided at its lower end with a downwardly opening recess 16 having an inside
diameter `substantially equal to the outside diameter of the inner cylinder 5 on the
stationary cap 1. In addition, an annular cylinder 17 for fitting in the outer peripheral
recess 8 of the stationary cap 1 is formed on the outer periphery of the spray head.
The fitting recess 16 in the spray head has a diameter substantially equal to the
outside diameter of the inner cylinder 5. A fitting surface 18 for mating with the
fitting surface 9 of the of the inner cylinder 5 is formed on the inner periphery
of the fitting recess 16. Axial guide slits 19 are formed to extend from the lower
end of the fitting surface 18 to a prdetermined height so as to receive the ribs 11
formed in the inner cylinder 5. The spray head 10 having the convexity and concavity
has to fit to the complementary surface of the stationary cap 1 when the same is set
on the plunger 4. To this end, the connection between the plunger 4 and the spray
head 10 are accomplished by aligning the ribs 11 on the stationary cap 1 and the guide
slits 19 in the spray head 10. By making the ribs 11 fit in the guide slits 19, the
ribs 11 are retained by the side walls of the slits to prevent the spray head 10 from
rotating to ensure that the initial optimum direction of the nozzle is maintained
permanentally. On the other hand, the ribs 11 provide a good guide for the vertical
movement of the plunger so that the upward and downward stroking of the spray head
10 can be made in quite a stable manner. If the length of fit between the plunger
4 and the spray head 10 is short, the spray head may be declined when the same is
pushed downward to impair the vertical depression of the plunger 4. However, in the
spray head of the invention, the undesirable lateral oscillation and declining of
the spray head are avoided because a very stiff connection is achieved by the fitting
engagement with the stationary cap.
[0013] Fig. 3 shows another embodiment having a different construction for rotation prevention
fitting between the spray head 10 and the stationary cap 1. In this embodiment, the
fitting surface 9 is formed on the inner periphery of the inner cylinder 5 of the
cap 1, and the guide slits 19 are formed in the fitting surface 9 to extend from the
upper end to lower end of the cylinder. The spray head 10 has a mounting cylinder
20 for mountng the plunger 4, and the fitting surface 19 is formed on the outer periphery
of the cylinder 20. The fitting surface 19 is provided with ribs or small projections
which serve to prevent the rotation as in the case of the construction shown in Fig.
1. In this embodiment, the annular cylinder 17 on the spray head 10 may be omitted
but, preferably, this cylinder 17 is formed from the view point of design or appearance
of the spray head.
[0014] Fig. 5 shows still another embodiment having a different construction for rotation
prevention fitting between the spray head 10 and the stationary cap 1. The stationary
cap 1 has the outer cylinder 6 the inner peripheral surfaceof which serving as the
fitting surface 9 in which formed are the guide slits 19. On the other hand, ribs
11 and other small protrusions are formed on the fitting surface 18 on the outer periphery
of the annular cylinder 17 of the spray head 10. A reference numeral 21 designates
a suction pipe which extends downwardly from the lower end of the pump cylinder 3.
[0015] As has been described, in the spray pump of the invention, a fitting projection is
formed in one of the opposing surfaces of the ceiling plate la of the stationary cap
1 and the spray head 10 while a cooperating fitting recess is formed in the other
surface. One of these fitting surfaces is provided with ribs or the like protrusions
while the other is provided with slits. The arrangement is such that the fitting engagement
between the stationary cap 1 and the spray head 10 is achieved when the spray head
10 is assembled. Therefore, the spray head secured to the plunger in the correct orientation
or direction is prevented from rotating relatively to the stationary cap to maintain
the correct initial set condition permanentally. The convexity and concavity formed
in the fitting surfaces of the spray head and the plunger are effective to some extent
in weakening the rotation prevention force to facilitate the work for setting the
spray head and in guiding the spray head when the latter is reciprocally moved up
and down, thereby to ensure a correct operation of the spray head.