Abstrict A pill crusher has an arm extending over and along an elongate
base, with a pivotal connection between the base and one end of
the arm. An upwardly open cylindrical housing on the base has a
longitudinal axis perpendicular to the base and a compression spring
in the cylindrical housing between a cylindrical anvil member and
the base. Interengaged guide formations on the housing and the anvil
member at opposite sides of the housing are inclined so as to cause
rotational movement of the anvil member relative to the cylindrical
housing on displacement of the anvil member along the longitudinal
axis against the action of the spring; and a cylindrical pressure
member depending from the arm above the cylindrical housing. In
use, the rotational movement of the anvil member causes a pill to
be both crushed and also simultaneously ground between the pressure
and anvil members, which have serrated opposed faces to improve
the grinding.
Claims I claim:
1. A pill crusher, comprising: an elongate base; an arm extending
over and along said elongate base; a pivotal connection between
said base and one end of said arm; an upwardly open cylindrical
housing on said base, said cylindrical housing having a longitudinal
axis perpendicular to said base; a cylindrical anvil member in said
cylindrical housing; a compression spring in said cylindrical housing
between said anvil member and said base; interengaged guide formations
on said housing and said anvil member at opposite sides of said
housing, said guide formations being inclined so as to cause rotational
movement of said anvil member relative to said cylindrical housing
on displacement of said anvil member along said longitudinal axis
against the action of said spring; and a cylindrical pressure member
depending from said arm above said cylindrical housing.
2. A pill crusher as claimed in claim 1 wherein said interengaged
formations comprise cam surfaces on said cylindrical housing and
cam followers projecting from said anvil member into contact with
said cam surfaces.
3. A pill crusher as claimed in claim 1 wherein said interengaged
formations comprises slots in said cylindrical housing and projections
extending from the opposite sides of said anvil member into said
slots.
4. A pill crusher as claimed in claim 1 wherein said pressure
member has a serrated undersurface facing said anvil member.
5. A pill crusher as claimed in claim 1 wherein said anvil member
has a serrated upper surface.
6. A pill crusher as claimed in claim 1 including a pivotal connection
between said arm and said pressure member, said pivotal connection
having an axis of pivotation transverse to the length of said arm.
7. A pill crusher as claimed in claim 1 wherein said anvil member
protrudes upwardly from said cylindrical housing.
8. A pill crusher as claimed in claim 1 including a spade handle
at an opposite end of said arm.
9. A pill crusher, comprising: a base; an upwardly open cylindrical
housing on said base; a compression spring in said cylindrical housing;
an anvil member on said compression spring, said anvil member being
downwardly movable relative to said cylindrical housing against
the action of said compression spring; an arm extending over said
base; a pivotal connection between one end of said arm and said
base; a pressure member depending from said arm above said cylindrical
housing and movable onto said anvil member, by pivotation of said
arm relative to said base, to effect downward displacement of said
anvil member relative to said cylindrical housing; and means for
effecting relative rotational movement of said pressure member and
said anvil member during said downward displacement.
10. A pill crusher as claimed in claim 9 wherein said anvil member
and said pressure member have opposed serrated surfaces.
11. A pill crusher as claimed in claim 9 wherein said means for
effecting relative rotational movement comprises cam surfaces and
cam followers on said anvil member and said pressure member.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to pill crushers for use in crushing
medicaments in the form of pills or tablets.
2. Description of the Related Art
Medications are commonly provided in the form of pills or tablets,
and it is well known that these can be difficult to swallow for
various persons. Consequently, various pill crushers have been proposed
in the prior art for crushing pills and tablets so as to convert
the medications into powder form, which can be more easily ingested
by such persons.
For example, U.S. Pat. No. 3915393 issued Oct. 20 1975 to Bill
Webb Elkins, discloses an apparatus for crushing medications, such
as pills, tablets and the like, which includes a base member having
a crushing bowl formed therewith, which is adapted to receive a
medication cup containing medicine to be crushed. The apparatus
further-includes a crushing arm pivotally mounted on the base member
and having a crusher head mounted on the crushing arm. By pivoting
the crushing arm relative to the base member, the crusher head can
be forced downwardly onto the medication, which is contained between
a pair of interengaged cups positioned in the crushing bowl.
In this prior apparatus, the crushing head is fixedly secured to
the crushing arm, and the interengaged cups are supported on the
base member. Therefore, there is no relative rotational movement
between the undersurface of the crushing head, and the upper surface
of the base member, on which the cups are supported, during the
crushing of the medication. Consequently, it has been found, in
practice, that the medications are not sufficiently pulverized by
such crushing action.
In U.S. Pat. No. 6357679 issued Mar. 19 2000 to George F. Radke,
there is disclosed apparatus for crushing medication having a crushing
member which is rotatable relative to an anvil, as medication is
crushed between the crushing member and the anvil. More particularly,
this prior apparatus has an anvil mounted on a base, and a crusher
member mounted in a housing for rotation about a first, horizontal
axis relative to the housing. The housing has a cam surface which
mates with a follower connected to the base, which produces rotational
movement of the housing about a second, vertical rotational axis
as the crushing member with its housing are displaced downwardly,
toward the anvil, in order to a crush medication provided between
interengaged cups between the crusher member and that the anvil.
It is, however, a disadvantage of the apparatus of U.S. Pat. No.
6 357679 that the force required for crushing medication must
be directed vertically downwardly onto the housing, so that there
is no lever action between the crusher member and the anvil. Consequently,
this prior art apparatus cannot easily be employed by weak or otherwise
disabled persons.
BRIEF SUMMARY OF THE INVENTION
It is, accordingly, an object of the present invention to provide
a novel and improved pill crusher which improves the crushing of
pills without requiring the application of any significant amount
of strength.
According to the present invention, a pill crusher comprises an
arm extending over and along an elongate base, with a pivotal connection
between the base and one end of the arm. An upwardly open, cylindrical
housing on the base has a longitudinal axis perpendicular to the
base, and a cylindrical anvil is provided in the cylindrical housing
on a compression spring located between the anvil member and the
base.
Interengaged guide formations on the cylindrical housing and the
anvil member,at opposite sides of the housing, are inclined so as
to cause rotational movement of the anvil member relative to the
cylindrical housing upon displacement of the anvil member against
the action of the spring. A cylindrical pressure member depends
from the arm above the cylindrical housing.
When the apparatus according to the present invention is in use,
a pill it is inserted into a cup, and another cup is interengaged
with the first cup, so that the pill is located between the two
cups. The two cups, with the pill between them, are then placed
on the anvil member, and the arm is pivoted downwardly to bring
the cylindrical pressure member into the uppermost cup. During further
downward movement of the pressure member toward the anvil member,
the pill is crushed between the pressure member and the anvil member.
Furthermore, during this crushing of the pill, the downward movement
of the pressure member causes the anvil member to be downwardly
displaced relative to the cylindrical housing. This movement of
the anvil member relative to the cylindrical housing, through the
interengaged formations, causes relative rotational movement of
the pressure member and the anvil member. Therefore, the pill it
is not only crushed but is, also, simultaneously ground between
the two cups.
The combination of the force exerted on the pressure member by
the lever action of the arm, with the grinding of the medication
caused by the relative rotation of the pressure member and the anvil
member, has been found to produce improved pulverization of the
medication.
Furthermore, but it has been found that the pulverization of the
medication can be still further improved by the provision of serrations
on opposed services of the pressure member and the anvil member.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more readily understood from the
following description of a preferred embodiment of thereof, given
by way of example with reference to the accompanying drawings, in
which:
FIG. 1 shows a view in perspective of a pill crusher according
to the present invention;
FIG. 2 shows a broken-away side view of parts of the pill crusher
of FIG. 1;
FIG. 3 shows a view taken in cross-section along the line 3--3
of FIG. 2;
FIGS. 4 and 5 show top plan views of an anvil member, which is
a component of the pill crusher of the FIG. 1 in a partially rotated
position and a normal position, respectively;
THE PREFERRED EMBODIMENT
In the accompanying drawings, there is shown a pill crusher, indicated
generally by reference numeral 10 which has an elongate base, indicated
generally by reference numeral 12 and an arm indicated generally
by reference numeral 14.
The base 12 is provided, at one end of the base 12 with an upstanding,
bifurcated block 16 to which a lug 18 on one end of the arm 14
is connected by a pivot pin 20 so that there is a pivotal connection
between this end of the arm 14 and the base 12.
A spade handle, indicated generally by reference numeral 22 is
provided at the opposite end of the arm 14 to facilitate pivotation
of the arm 14 to and fro about the horizontal axis of the pivot
pin 20 relative to the base 12 by a weak or otherwise disabled
person.
On the base 12 there is provided a cylindrical housing 24 which
has a longitudinal axis perpendicular to the base 12 i.e. a vertical
longitudinal axis.
A cylindrical anvil member 26 which is coaxial with the cylindrical
housing 24 is provided in the housing 24 and protrudes upwardly
from the top of the housing 24. As can be seen from FIG. 3 the
anvil member 26 is mounted on a helical compression spring 28 which
is located between the base and the underside of the anvil member
26. The compression spring 28 is partially accommodated in a boring
30 in the bottom of the cylindrical housing 24 and receives a downwardly
protruding cylindrical projection 34 on the underside of the anvil
member 26.
The cylindrical housing 24 and the anvil member 26 are formed with
interengaged formations in the form of downwardly inclined slots
36 in the wall of the cylindrical housing 24 and projections in
the form of grub screws 38 projecting, at opposite sides of the
anvil member 26 from the anvil member 26 with which they are in
threaded engagement, into the slots 36 in the cylindrical housing
24. The slots 36 form cam surfaces, and the grub screws 38 form
cam followers in contact with these cam surfaces, so that when the
anvil member 26 is displaced downwardly relative to the cylindrical
housing 24 as described below, it is simultaneously rotated, through
a few degrees, about to the vertical longitudinal axis of the cylindrical
housing 24.
The arm 14 is formed, between the lug 18 and the handle 22 with
a downwardly projecting extension 40 at the lower end of which
a pressure member 42 is pivotally connected by a pivot pin 43 (FIG.
3). The downward extension 40 is so located that, on pivotation
of the arm 14 downwardly about the pivot pin 20 toward the base
12 the pressure member 42 is brought downwardly onto and substantially
in alignment with the anvil member 26 as shown in FIGS. 2 and 3.
Furthermore, the cylindrical housing 24 is located at a position
along the length of the base 12 which is relatively close to the
pivot pin 20 and as will be apparent to those skilled in the art,
the purpose of this is to provide an appropriate lever moment to
facilitate the pressing of the pressure member 42 downwardly onto
the anvil member 26 by a person grasping the handle 22 in such
a manner as to substantially minimize the force required to be exerted
by that person on the handle 22.
The underside of the pressure member 42 is formed with serrations
44 and the top of the anvil member 26 is formed with serrations
46.
During operation of the pill crusher 10 a pill or tablet 48 is
inserted into a first cup 50 and a second cup 52 is then inserted
into the cup 50 on top of the pill 48 as shown in FIG. 2. The thus-interengaged
cups 50 and 52 with the pill 48 between them, are mounted on the
top of the anvil member 26 and the lever arm 14 is pivoted about
the pivot pin 20 to bring the pressure member 42 downwardly into
the uppermost cup 52 until it presses the base of the cup 52 downwardly
onto the pill 48. Further downward movement of the pressure member
42 causes crushing of the pill 48 and, simultaneously, forces the
anvil member 26 to be displaced downwardly relative to the cylindrical
housing 24. Due to the grub screws 38 and the slots 36 this downward
movement of the anvil member 26 relative to the cylindrical housing
24 causes a simultaneous partial rotational movement of the anvil
member 26 about the vertical longitudinal axis of the cylindrical
housing 24 as described above, through an angle .alpha., as shown
in FIG. 4 from its normal, unrotated position, in which it is shown
in FIG. 5 so that the pill 48 is simultaneously ground as well
as being crushed. This combination of crushing and grinding of the
pill 48 which it is facilitated by the serrations 44 and 46 produces
a very effective pulverization of the pill 48.
As will be appreciated by those skilled in the art, various modifications
may be made in the above-described embodiment of the present invention
within the scope of the appended claims.
For example, the spade handle 22 may be replaced by a crossbar,
extending at right angles to the length of the arm 14 and secured
by a screw to the free end of the arm 14. This facilitates gripping
of the handle.
In that case, the shape of the arm may be modified so that the
arm curves downwardly from the extension 40 and then extends substantially
vertically to the crossbar, so that there is less obstruction to
the fingers of a user gripping the handle. |