Dispenser for viscous materials

A dispenser for viscous materials such as toothpaste is disclosed. The dispenser comprises an elongated container having a spout at its upper end and a rockable finger actuator operable to dispense contents when depressed. The actuator is connected to an elongated operating rod which is coupled to a follower by means of a spray clutch which causes the follower to move upwardly in the container in increments in response to rocking motion of the actuator. The lower end of the operating rod is connected to a base member having a resilient portion and a peripheral recess which receives the lower end of the container. The resilient portion of the base member pulls the operating rod downwardly for repositioning the same after each stroke of the actuator, and the operating rod pulls upwardly on the base member to securely mount the same to the container.

FIELD OF THE INVENTION 
The present invention relates to dispensers for viscous materials, and more 
particularly, the present invention relates to a viscous material 
dispenser of the type having a container in which a follower is displaced 
axially toward a spout by an operating rod connected to an actuator. 
BACKGROUND OF THE INVENTION 
Various types of viscous material dispensers are known. Examples of such 
dispensers may be found in the following U.S. Pat. Nos.: 949,545; 
1,212,010; 1,244,324; 1,668,511; 1,921,912; 2,151,684; 2,243,774; 
2,557,952; 2,604,858; 2,732,101; 3,088,636; 3,215,320; 3,255,935; 
3,361,305; 3,768,705; 4,154,371; 4,301,948; 4,413,759; 4,421,255; 
4,437,584; 4,437,591; and 4,461,403. While the patented dispensers may 
function satisfactorily for their intended purposes, there is a need for a 
viscous material dispenser which is reliable in operation, which has a 
minimum of parts, and which is inexpensive to manufacture. 
OBJECTS OF THE INVENTION 
With the foregoing in mind, a primary object of the present invention is to 
provide a novel viscous material dispenser which overcomes the limitations 
of known viscous material dispensers. 
Another object of the present invention is to provide an improved viscous 
material dispenser which is reliable in operation. 
A further object of the present invention is to provide a unique viscous 
material dispenser which can be manufactured and filled economically 
utilizing a high-speed mass production equipment. 
SUMMARY OF THE INVENTION 
More specifically, the present invention provides an improved dispenser 
which is particularly suited for use in dispensing viscous materials, such 
as toothpaste. The dispenser comprises an elongated container having an 
upper end with a spout and a finger-actuated rocker arm actuator. An 
elongated operating rod is connected at its upper end to the actuator and 
depends therefrom axially inside the container where it is connected by a 
sprag clutch assembly to a follower. Rocking motion of the actuator causes 
the operating rod to reciprocate for advancing the follower upwardly in 
the container for dispensing contents from the spout. A base member has a 
resilient portion extending across the lower end of the container and 
engaging the lower end of the operating rod for biasing the same 
downwardly to reposition it relative to the follower after each dispensing 
stroke. A recess in the base member receives the lower end of the 
container and cooperates with the operating rod to securely mount the base 
member to the container.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, FIG. 1 illustrates a dispenser 10 which 
embodies the present invention. The dispenser 10 is particularly suited 
for use in dispensing viscous materials such as toothpaste, shampoo, 
grease, etc. Accordingly, while reference hereinafter will be made to 
toothpaste, it should be understood that the dispenser of the present 
invention can be used to dispense a variety of products. 
As best seen in FIG. 1, the dispenser 10 comprises an elongated tubular 
container 1 having an upper end 11a with a transverse end wall 12 and a 
lower end 11b. The lower end 11b terminates in a circular edge defining an 
opening through which the container 11 is filled when inverted. A 
dispensing spout 13 is formed integral with the upper end wall 12 of the 
container 11 and projects upwardly therefrom to one side of its 
longitudinal axis. An annular rib 15 on the end wall 12 cooperates with a 
complementary rib 16 on a cap 14 to hold the cap 14 in place on top of the 
container 11 in the manner illustrated in FIG. 1. 
The container 11 is adapted to contain toothpaste T and to dispense the 
same from the spout 13 after the cap 14 has been removed. To this end, a 
follower 17 is mounted in the container 11 for movement axially therein to 
pressurize the toothpaste T. The follower 17 has a peripheral skirt 17a 
which engages the inner periphery of the container 11. The skirt 17a 
slidably engages the inside of the container 11 in a fluid tight manner to 
prevent the contents thereof from leaking. 
The follower 17 is displaced upwardly in the container 11 by means of an 
operating rod 18. As best seen in FIG. 1, the operating rod 18 extends 
axially inside the container 11 for substantially its entire length. The 
operating rod 18 has a lower end 18a located adjacent to the bottom of the 
container 11, an upper end 18b located adjacent to the top of the 
container 11, and a series of annular ribs 18c spaced apart in increments 
along substantially its entire length. 
The operating rod 18 is connected to the follower 17 by means which causes 
the follower 17 to move unidirectionally upward when the rod 18 is 
displaced upwardly. To this end, a metal-stamped sprag clutch assembly 19 
having a series of flexible fingers 19a, 19b engages the operating rod 18 
between the ribs 18c as shown in FIGS. 1 and 3 to grip the rod 18 in a 
downward direction so that when the rod 18 moves upwardly, it causes the 
follower to move upwardly with it. The sprag clutch assembly 19 permits 
the rod 18 to move downwardly relative to the follower 17 in a well known 
manner. 
To displace the operating rod 18 upwardly, the upper end 18b of the 
operating rod 18 is connected by means of a flexible strap, or hinge, 20 
to a rocker arm finger actuator 21 mounted in a trunnion 22 formed on the 
end wall 12 of the container 11. The strap 20 is molded integral with the 
rod 18 and the finger actuator 21 of the same plastic material. Pivotal 
movement, or depression, of the finger actuator 21 clockwise in the 
direction indicated by the arrow in FIG. 1 causes the operating rod 18 to 
move upwardly in the container 11, and this advances the follower 17 
upwardly and applies pressure to the toothpaste T for causing it to flow 
out the spout 13. 
A prior art dispenser of the type just described is disclosed in U.S. Pat. 
No. 4,437,591, the disclosure of which is incorporated by reference 
herein. In the patented dispenser, a spring element is provided for 
pivoting the finger actuator in the counterclockwise direction for urging 
the operating rod downwardly relative to the follower at the completion of 
a dispensing stroke to reposition the rod with respect to the follower and 
to ready the same for the next dispensing stroke. In this dispenser, the 
spring element is formed integral with the finger actuator and engages the 
upper end wall of the container for effecting the desired counterclockwise 
pivotal movement of the finger actuator. With this container, however, it 
has been necessary for the hinge to be fabricated of a special plastic 
material capable of sustaining the alternate tension and compression loads 
on the operating rod. While the operating rod itself can be fabricated of 
a low cost plastic, it has been necessary to fabricate the plastic 
material of the hinge of a more expensive grade of plastic, and this 
necessitates a more complex molding operation. Furthermore, in such 
containers, the hinge has been a source of failure of the product because 
of the repeated stressing of the hinge axially in opposite directions 
while undergoing flexure. 
The present invention overcomes the aforementioned limitations of a known 
prior art container of the type described and provides a dispenser which 
is durable and yet which can be manufactured economically. To this end, a 
means is provided for maintaining downward tension on the operating rod so 
that the hinge is maintained in tension at all times. This is accomplished 
in the present invention by providing a base member 25 which functions 
both as a container base and as an operating rod biasing means. 
To this end, and as best seen in FIG. 1, the base member 25 has a resilient 
wall portion 26 extending transversely across the lower end 11b of the 
container 11 and a peripheral recess 27 which receives and engages the 
lower end 11b of the container 11. The base member 25 has an outwardly 
extending and downwardly depending flared portion 28 with a lower edge 28' 
adapted to engage a support surface to support the container 11 upright. 
Preferably, the flared portion 28 has one or more straight sides 28a, 28b 
(FIGS. 2 and 4) to prevent the container 11 from rolling when laid on its 
side. 
The base member 25 operatively engages the operating rod 18. For this 
purpose, the resilient wall portion 26 of the base member 25 has a central 
aperture 26a through which the lower end 18a of the operating rod 18 
depends. The lower end 18a of the operating rod has an integral barbed 
head 18c having an annular shoulder 18' which engages the underside of 
the resilient wall portion 26 of the base member 25, and the head 18c is 
tapered in the manner illustrated. Thus, the base member 25 can be mounted 
on the lower end 11b of the container 11 and connected to the operating 
rod 18 simply by pushing the base member 25 axially with respect to the 
container 11 until the operating rod head 18c passes through the aperture 
26a and the shoulder 18' engages the underside of the resilient wall 26. 
The base member 25 positively biases the operating rod 18 downwardly. To 
this end, the resilient wall 26 has a concave, or dished, configuration, 
such as illustrated, and it deflects upwardly in response to upward 
movement of the operating rod 18 when the finger actuator 21 is pivoted 
clockwise in the direction indicated by the arrow. 
In the illustrated embodiment, a stop surface 22a is provided adjacent to 
the spout 13 for engaging the finger actuator 21 to limit its pivotal 
movement in the counterclockwise direction. Thus, the stop 22a and 
trunnion 22 cooperate with the resilient wall portion 26 of the base 
member 25 to maintain tension on the operating rod 18 and its strap 20. 
The cap 14 aids in the assembly of the dispenser 10 by stabilizing the 
position of the operating rod 18. To this end, the inside of the cap 14 is 
provided with a series of centrally located gussets 14a, 14b which depend 
from its end wall 14c and engage the topside of the finger actuator 21 in 
alignment with the strap 20 and operating rod 18 when the cap 14 is 
mounted on the container 11. The cap 14, and its gussets 14a, 14b, prevent 
the operating rod 18 from moving axially in the container 11 when the 
follower 17 is engaged with the operating rod 18 and the base member 25 is 
assembled onto the lower end 11b of the container 11 after the container 
11 has been filled with toothpaste T. After engagement of the operating 
rod 18 and base wall 26 in the manner illustrated, the flexible wall 
portion 26 of the base member 25 applies a slight amount of tension to the 
operating rod 18, and thereby to the strap 20, for causing the finger 
actuator 21 to normally assume the home, or inactive, position illustrated 
in FIG. 1. 
In use, the gap 14 is removed from the container 11 and the dispensing 
spout 13 positioned in dispensing relation with respect to the bristles of 
a toothbrush. A person then engages a thumb or finger with the finger 
actuator 21 and pivots the same clockwise in the direction of the arrow in 
FIG. 1. As the actuator 21 moves clockwise, it pulls upwardly on the strap 
20 while flexing the same, and the strap 20, in turn, pulls upwardly on 
the operating rod 18. By virtue of the sprag clutch assembly 19 
interconnecting the follower 17 with the operating rod 18, the follower 17 
is pulled upwardly in the container 11 along with the operating rod 18. 
As the follower 17 moves upwardly, it pressurizes the toothpaste T in the 
container 11, and this causes the toothpaste to flow out the spout 13. At 
the same time, the resilient flexible wall 26 of the base member 25 flexes 
upwardly by virtue of its interconnection with the lower end 18a of the 
operating rod 18 and the bottom of the container 11 continuing to maintain 
tension on the operating rod 18. When pressure is released from the finger 
actuator 21, however, the resilient wall 26 flexes downwardly toward the 
position illustrated in FIG. 1, enabling the sprag clutch 19 to permit the 
operating rod 18 to move downwardly with respect to the follower 17. The 
resilient wall 26 continues to pull the operating rod 18 downwardly until 
the finger actuator 21 engages its stop 22a. Thus, the finger actuator 21 
is returned to its home position, and the follower 17 is reengaged with 
the operating rod 19 at a higher position to ready the dispenser 10 for 
the next dispensing stroke. 
The container 10 may be stored upright in the manner illustrated in FIG. 1, 
or it may be laid down on its side without rolling as a result of the flat 
surfaces provided on the base member 25. 
The aforedescribed structure has a number of advantages. First of all, the 
resilient wall portion 26 of the base member 25 exerts a relatively strong 
pull on the operating rod 18 to insure that it maintains the operating rod 
18 under tension and causes it to reengage the follower at new location to 
be ready for the next dispensing stroke. Since the strap 20 does not 
undergo compressive stresses in use, it is fatigue resistant and therefore 
resistant to failure. Thus, the operating rod 18 and its strap 20, can be 
molded of the same low cost plastic in a straightforward molding 
procedure. The novel base member 25 provides, not only a means for biasing 
the operating rod 18 downwardly, but also a closure for the lower end of 
the container to prevent foreign matter from entering the same. 
Furthermore, the design of the base member 20 is such as to be capable of 
being molded in one piece and assembled readily with the container 11 
simply by pushing the same together. Accordingly, the dispenser 10 of the 
present invention is not only economical to manufacture, but it is also 
durable and reliable in use. 
While a preferred embodiment of the present invention has been described in 
detail, various modifications, alterations and changes may be made without 
departing from the spirit and scope of the present invention as defined in 
the appended claims.