Note: Descriptions are shown in the official language in which they were submitted.
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ADJUSTABLE SPRING ANGLE ON VIBRATORY BOWL FEEDERS
The invention has to do with providing adjustability
for leaf spring suspension elements in vibratory bowl
feeders. More specifically, interchangeable components
are provided in a suspension structure to allow adjustment
of the angles of the leaf spring mountings of the feeder.
Vibratory bowl feeder apparatus, typically including
a base and a driven component mounted on spring to the
base, are vibrated through the use of an electromagnetic
exciter. The frequency of the exciter's operation is
dictated by the line frequency of the power source. Since
feed rates vary for different materials or articles and
since a bowl feeder should have some flexibility over the
range and type of material that it is able to feed, some
adjustment of the angle of motion is desirable.
According to an aspect of this invention, a vibratory
material feeder of the type having a material feeder
resiliently mounted to a base by a leaf spring suspension,
the material feeder and the base having leaf spring
mounting faces, and means for angularly adjusting the
plane of the leaf spring suspension for changing the
frequency of the material feeder, the angular adjusting
means comprises at least one wedge member sandwiched
between one of the leaf spring suspension and one of the
associated leaf spring mounting faces, the wedge member
having one face parallel with the plane of the leaf spring
suspension and a second face non-parallel with the plane
of the leaf spring suspension, the faces having an
aperture there through, and a bolt extending through the
apertures in the leaf spring and the faces of the wedge
member connecting the one end of the leaf spring
suspension to the associated leaf spring mounting face.
According to another aspect of the invention, a
method of adjusting the leaf spring suspension of a
vibratory bowl feeder having a base and a driven component
mounted on leaf springs to the base, the leaf springs
being removably attached at each end to spring mounting
blocks respectively forming part of the base and the
driven member, the method comprises inserting wedge
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spacers, of which opposed faces are angled to one another,
between the spring ends and the respective mounting block.
The advantages of this invention and a complete
understanding thereof will be apparent from the following
description and study of the drawing figures wherein:
Figure 1 presents a plan view of a vibratory bowl
feeder;
Figure 2 present a side elevation view of Figure l;
Figures 3, 4 and 5 present a single leaf spring
assembly with several combinations of spacers yielding
several different leaf spring angles.
The Figure 1 view is a plan view of a vibratory bowl
feeder generally 10 having a base 12 that supports a cross
arm element 14 to which a bowl, not shown, is attached in
a conventional manner. Each of the appendages such as 16
of the cross arm element 14 are attached to an individual
stack of leaf springs such as 20. Each leaf spring stack
20 may be composed of either a single leaf or a plurality
of leaves and the two leaf spring stacks shown here are
simple an example of a preferred embodiment.
The elevation view of Figure 2 shows the cross arm
element 14, which is a supported member, and the
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appendage 16 supported by the four leaf spring stacks such
as 20 to the base 12. The base 12 is a generally
rectangular plate of significant mass that is provided
with cutouts such as 22 to accommodate mounting of the
leaf springs within the general perimeter of the machine.
Each cutout 22 projects normally from the edges of the
base toward the center thereof and is machined generally
as shown in Figure 2 so that at least a first face 24,
hereinafter the base face of the base cutout, is formed at
an angle to the vertical reference 26. In a preferred
embodiment this base face angle would be 25.
figure 2 also shows that the appendages such as
16 are provided with an appendage face such as 30 that is
machined on an angle relative to the vertical reference 26
in a direction opposite that of the first face angle of
the base cutout. In a preferred embodiment this may be an
angle of 15.
Each end of each leaf spring 20 is provided with
a through aperture for accommodating a spring clamping
bolt such as 32. There are eight identical bolts used in
the embodiment shown but other fastening arrangements are
contemplated. The bolts are ultimately received in
drilled and tapped bores in respective base faces 24 and
appendage faces 30 of the base 12 and the cross arm
element 14 respectively. All the spring clamping bolt
receiving bores are drilled at an angle to the horizontal
plane of equal slope. In this embodiment the bores are
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drilled at 20 from the horizontal and are parallel to
each other.
In order to provide the leaf spring mounting
angle's adjustability a plurality of flat spacers and
wedges are provided For purposes of this disclosure a
flat spacer is a rectangular piece of stock having a given
thickness and large flat faces on each side thereof with
these faces being generally parallel to each other. These
flat spacers, such as the one shown as 40 in Figure 2, are
also provided with a hole that allows passage of the
spring clamping bolt 32.
The wedges such as 42 in Figure 2 are similar to
the flat spacers 40 except that the opposite large flat
faces are formed at different angles to the normal plane
thereof. For instance, a first face 44 is parallel to the
normal plane while a second face 46 is formed at 5 from
the normal plane, thus 5 relative to the first face 44.
The wedges are also provided with a hole to accommodate
the spring clamp bolts such as 32.
The flat spacers 40 and the wedges 42 are
arranged relative to the leaf spring stack 20, to provide
various leaf spring angles shown in Figures 3 through 5.
In Figure 3 the leaf spring stacks are positioned
at a 15 angle to the vertical as shown by included angle
A. In this figure it can be seen that the appendage face
30 is formed on the appendage 16 of the cross arm element
at an angle of 15, reference 50, from the vertical
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reference 26. On the base 12 it can be seen that the face
24 is machined or formed at an angle of 25, reference 52,
from the vertical reference 26. These face angles of the
appendage face 30 and the cutout face 24 are constant in
all of the exemplary versions shown but could be changed
depending on designer's preference.
To get the 15 angle A through the leaf spring
embodiment shown in Figure 3 the following arrangement of
spacers is used. Since the cross arm appendage face 30 is
already machined at 15 no spacers are needed between the
upper ends of the leaf spring stacks and the appendage
face 30. A wedge 42 is needed outboard of the leaf spring
stacks to assure that the head of the spring clamping bolt
contacts a surface which remains perpendicular to the
major axis of the bore 34 and the bolt is not deflected by
eccentric loads. The wedge 42 provides a face that is
parallel to the appendage face 30 of the cross arm
appendage. At the base cutout 22 where the base face 24
is formed at 25 to vertical two identical wedges aye and
42b are needed between the leaf spring stacks and the base
face 24. The two wedges aye and 42b have their normal
faces abutting each other so that a 10 wedge is
constructed thus bringing the base face actual angle down
to 15 from 25. Outboard of the springs a single wedge
~42c~ is used to assure that the bolt head aye contacts a
surface which is 20 from the vertical reference an it
not deflected by eccentric loads.
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In the Figure 4 embodiment a 20 included angle B
between the leaf spring stack 20 and the vertical
reference 26 is developed. Of course the elements used
here are the same as those used in Figures l, 2 and 3
except that the flat spacers and wedges are arranged
differently. Specifically at the cross arm a wedge 42d is
placed between the leaf spring 20 and the appendage face
30 to steepen the face angle from 15 at 50 to 20. Since
this face provides a complimentary angle for the spring
clamping bolt 32 a flat spacer 40 is used outboard or the
springs. At the base, where the base face is 25 (52) a
wedge eye is used to bring the angle to 20 between the
leaf spring 20 and the vertical reference 26. Outboard of
the leaf spring 20 only a flat spacer is needed to assure
concentric loading for the spring clamping bolt aye.
In the Figure 5 embodiment a 25 included angle C
is provided by inserting 10 of wedges, namely wedges 42f
and 42g of 5 each between the leaf spring stacks and the
appendage face 30. Outboard at the top end of the leaf
spring stack a third wedge 421 is needed to get the
contact surface alignment back to 20 so the spring clamp
bolt 32 is concentrically loaded. At toe base no wedges
are needed as the base face 24 is formed at 25, there-
fore, the leaf spring stack is directly mounted adjacent
the base face 24. A wedge 42j is used, however, to
realign the spring clamp bolt aye and the threaded bore in
the cross arm.
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Although this disclosure deals with wedges having
the face 5 from the normal plane and specific appendage
face and base cutout face angular displacements it should
be obvious that this disclosure attempts to set forth a
S preferred embodiment and thus minor changes in angular
values will be considered within the scope of this disk
closure. Furthermore, the quantities of elements are not
critical to the invention hence bases with more than four
cutouts and cross arms with a plurality of arms are also
contemplated.
Thus it can be seen that there has been provided
a vibratory bowl feeder having adjustable spring angles
provided by a set of flat spacers and wedges that fully
meets the objects of the invention. The inventor contem-
plates that several nuances of design are possible and such variations are intended to fall within the scope of
the following claims.
