U.S. patent number 3,756,150 [Application Number 05/150,635] was granted by the patent office on 1973-09-04 for trash compactor ram.
This patent grant is currently assigned to Amana Refrigeration, Inc.. Invention is credited to Joseph F. Bourgeois.
United States Patent |
3,756,150 |
Bourgeois |
September 4, 1973 |
TRASH COMPACTOR RAM
Abstract
A trash compactor employs a vertically descending ram operated
by a single, centrally disposed motor driven screw swivelly
attached to the ram to accommodate tilting of the latter during
compacting. The head of the ram is removable and of a scalloped
shape for better compaction of cans and bottles. The ram engages
trash deposited in a round, bucket-like container supported on
springs carried on a slide-out mount from which the container is
removable, compaction causing the container to descend against its
supporting springs until it seats on the base of the compactor. The
container incorporates a liner, a disposable bag and several shield
plates to protect the container and the bag. An electrical control
circuit is included, together with several safety interlocks, for
actuating the ram and automatically reversing it.
Inventors: |
Bourgeois; Joseph F. (Cedar
Rapids, IA) |
Assignee: |
Amana Refrigeration, Inc.
(Amana, IA)
|
Family
ID: |
22535387 |
Appl.
No.: |
05/150,635 |
Filed: |
June 7, 1971 |
Current U.S.
Class: |
100/229A;
100/289; 141/390; 220/908; 220/495.11 |
Current CPC
Class: |
B30B
9/30 (20130101); B30B 9/3064 (20130101); Y10S
220/908 (20130101) |
Current International
Class: |
B30B
9/30 (20060101); B30B 9/00 (20060101); B30b () |
Field of
Search: |
;100/52,53,214,229A,229R,295,289,240 ;220/65 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wilhite; Billy J.
Claims
I claim:
1. In a trash compactor having a ram assembly movable in a
substantially vertical path; a container in trash compacting
position beneath said ram assembly and movable therefrom for
emptying; power operated means for moving said ram assembly in a
compacting stroke downwardly into said container substantially its
full effective depth and then upwardly along said path so that said
container can be removed for emptying, said power operated means
exerting force upon said ram assembly in a single axis of thrust
normally parallel to said path and including a single screw and
threaded means carried by said ram assembly permitting swivel
movement of said assembly relative to said axis; and a plurality of
stationary guides for said ram assembly extending parallel to said
thrust axis and spaced remotely from and about said axis and screw
outboard of the exterior of said container, the improvement in said
ram assembly comprising: a substantially horizontal top member
carrying said threaded means and centrally disposed with respect to
said axis; opposite skirt members depending extensively from said
top member, said skirt members slidably engaging said stationary
guides during movement of said assembly and spaced from and about
said thrust axis to pass outboard of the exterior of said container
during the compacting stroke of said ram assembly; a ram head
beneath said top member having a compacting face normal to said
path and centrally disposed with respect to said thrust axis, said
ram head being fittingly received in said container during said
compacting stroke, the perimeter of said ram head being inboard of
said skirt members; and means connecting said ram head to said top
member and spacing said compacting face therebelow a distance
substantially equal to the full effective depth of said container,
the outer confines of said connecting means lying inboard of the
perimeter of said ram head, said connecting means and said top and
skirt members together being effective to resist tilting of said
ram head during said compacting stroke.
2. The compactor of claim 1 wherein said top member comprises a
rectangular top plate and said skirt members a pair of rectangular
plates depending therefrom having vertical angular corner portions
with friction reducing material disposed thereover and slidably
engaging said stationary guides, said stationary guides comprising
a plurality of angular channels.
3. The compactor of claim 2 wherein said threaded means includes an
internally threaded nut mounted to said top plate against rotation
relative thereto and said screw is rotably driven, said mounting
also preventing movement of said threaded member relative to said
assembly in either direction along said thrust axis.
4. The compactor of claim 2 wherein the outer confines of said
connecting means extend convergingly upwardly from closely adjacent
the perimeter of said ram head and are attached to the underside of
said top plate closely adjacent and about said thrust axis and said
threaded means.
5. The compactor of claim 4 wherein said connecting means comprise
a pair of formed plate members, each of said members including a
central trapezoidal portion having its converging edges extending
upwards from said ram head to said top plate, said trapezoidal
portions being disposed in spaced facing relation on opposite sides
of said screw, each of said trapezoidal portions having reinforcing
portions along their entire converging edges, said reinforcing
portions being angled with respect to said trapezoidal portions
outwardly toward the perimeter of said ram head and secured to said
top plate and said ram head.
6. The compactor of claim 5 including a cabinet having a front
face, and wherein said top plate includes a first pair of opposite
edges normal to said face and spaced apart a greater distance than
a second pair of opposite edges of said plate parallel to said
face, said skirt plates depending from said first pair of
edges.
7. The compactor of claim 5 wherein said trapezoidal portions are
disposed generally parallel to said second pair of said top plate
edges, said reinforcing portions being angled outwardly toward said
last-named pair of plate edges.
Description
BACKGROUND OF THE INVENTION
Previous designs of trash compactors, especially for domestic use,
typically use two or more screws to drive the ram, thus increasing
the complexity and cost of the unit but not materially its
efficiency. For instance, the compactor in U. S. Pat. No. 3,353,478
employs three such screws equally spaced about a cylindrical ram
head, while that in U. S. Pat. No. 3,537,390 uses two such screws
disposed on opposite sides of a rectangular ram head. The trash to
be compacted is typically a mixture of hard and soft items, such as
cans and bottles on the one hand and paper and plastic on the
other. Consequently, the ram tends to cock at an angle when one
portion of its head engages paper while another portion engages a
bottle, for instance. The use of multiple screws in compactors of
the type concerned is an effort to accommodate these diverse
conditions, but as noted, at the price of increased cost and
complexity because of the additional screws and drive components
needed.
Another unfavorable aspect of prior trash compactors is the ram
head itself. These are typically integral with the ram and cannot
easily be removed for cleaning or replacement. Problems with them
have also been incurred on account of the size and shape of their
compacting faces. Clearance between the ram head and the container
is important, especially when a tapered container is used in order
more easily to remove the compacted trash. If the clearance is too
little, then articles can jam between the ram head and the
container; if it is too much, then smaller articles will be missed
or also jam. On the other hand, the area of the ram head should be
as small as possible in order to provide maximum pressure on the
trash with respect to the overall force applied to the ram. These
competing considerations have not been too well accommodated in
present trash compactors of the kind concerned.
The shape and construction of the container in which the trash is
compacted are still other deficiencies of the prior art. A
non-round, such as a rectangular-shaped, container is rather
unsatisfactory because a hard object, such as a round bottle, can
lie along one wall of the container so that the ram when it
descends contacts the bottle in a manner tending to urge it against
the container wall rather than against the container floor, whence
the container is pushed aside, sometimes even enough to injure or
halt the machine. A round container, on the other hand, is much
freer of that vice. Moreover, both round and non-round containers
previously employed lack protection for the disposable bag with
which the container is customarily lined in order for the compacted
trash to be removed. During the compacting stroke the bag is often
torn by sharp objects, such as cans and bottles, thus soiling the
interior of the container and perhaps even rendering the bag
ineffective for disposing of the trash, or in any event making it
impossible to seal against emission of odors.
Customarily, of course, some sort of electrical control circuit is
also employed for operating compactors of the kind concerned.
Typically, these provide for automatic reversal of the ram at the
bottom of its compacting stroke and include various safety
interlocks. However, such circuits have tended to be rather complex
and expensive, using current sensitive relays or other devices to
sense when the ram has encountered a predetermined amount of
resistance from the trash in order to reverse the ram's direction.
Some prior compactors even limit the compacting stroke to a fixed
distance above the bottom of the trash container regardless, thus
limiting or reducing the amount of compaction irrespective of the
nature or amount of the trash in the container. All of this is
unnecessary, and simpler, less costly and more efficient circuits
and components are obviously desirable from commercial and
performance standpoints.
SUMMARY OF THE INVENTION
The present invention here summarized and later claimed is confined
to the ram and its drive, although other inventive features of the
trash compactor are also shown in the drawings and disclosed in the
more detailed description which follows this summary.
The ram itself is constructed essentially from a broad, horizontal
upper plate of rectangular shape having a pair of deep skirt plates
whose four corners are provided with nylon glides which travel in
respective corners of a pair of broad, vertical channels fixed at
their ends to top and floor plates forming the chassis of the
compactor. Below the ram upper plate a pair of spaced trapezoidal
members extend downwardly and are fitted with a horizontal ram
bottom plate below which a removable ram head is attached. The
upper plate of the ram is centrally fitted with a swivel nut held
captive thereon which receives in turn a long vertical Acme drive
screw passing downwardly between the trapezoidal members. The top
of the screw above the upper ram plate is fitted with a large
cogged driven gear about which passes a cogged drive belt, being
driven by a smaller cogged drive gear fixed to the upper end of the
drive shaft of an appropriate electric motor vertically suspended
beneath the chassis top plate.
Accordingly, the four corners of the skirt plates, since they are
disposed substantial distances from the axis of the screw, provide
eight widely spaced and extensive vertical guide surfaces and
effectively restrain cocking of the ram during compaction of trash,
thus enabling a single drive screw to be employed rather than
several. The swivel nut accommodates what twisting of the ram may
occur to prevent binding and wear of the screw and the nut.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of the exterior of a trash compactor
according to the present invention illustrating the outer
cabinet.
FIG. 2 is a vertical elevation of the interior of the compactor
taken generally along the line 2--2 of FIG. 1, certain portions of
the chassis, the ram and its drive and the trash container mount
being additionally sectioned to illustrate their details.
FIG. 3 is a sectional view taken along the line 3--3 of FIG. 2 but
with the trash container mount omitted for more clarity.
FIG. 4 is an exploded isometric view of the ram and its drive.
FIG. 5 is an exploded isometric view of the removable ram head.
FIG. 6 is a bottom plan view of the removable ram head.
FIG. 7 is an enlarged isometric view of the slide-out mount for the
removable container in which the trash is compacted.
FIG. 8 is a detail view taken along the line 8--8 of FIG. 7.
FIG. 9 is an exploded view of the trash container itself
illustrating its components.
FIGS. 10A, B, C, D and E schematically illustrate the electrical
control circuit and its operating sequence during a compacting
cycle.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The trash compactor consists of a chassis 10 formed essentially of
a heavy, downwardly flanged rectangular floor plate 11 reinforced
beneath by a transverse channel assembly 12. Just inboard of and
along the side edges of the floor plate 11 are located two broad,
shallow vertical channels 13 disposed in facing relation to each
other as illustrated in FIGS. 2 and 3. The lower ends of the
channels 13 are provided with horizontal tongues 13a which pass
through slots 11a along the side flanges of the floor plate 11 and
engage its under face, being secured thereto by bolts 13b (see
FIGS. 2 and 7). The channels 13 extend nearly to the top of the
compactor and are capped by a heavy, downwardly flanged top plate
14, also reinforced above by a pair of transverse channel
assemblies 15. The respective opposite flanges of the channels 13
are connected by heavy crossplates 16 just beneath the top plate
14, all to form in effect a heavy, cage-like structure in which the
ram operates. Over the chassis 10 is slipped an open front,
rectangular sheet metal cabinet 17 whose forward edges are flanged
at 17a and provided with a toe space 18. The front of the cabinet
is closed by three panels, 19, 20 and 21 against the cabinet
flanges 17a, the upper edge of the panel 21 being provided with a
hand grip 22 for purposes to be later described. The cabinet 17 is
secured only to the rear and side edges of the floor plate 11,
being otherwise spaced from the chassis 10 in order to minimize
transmission of vibration, and the floor and top plates 11 and 14
extend forward to just behind the toe space 18 and the panel 19,
respectively, (see FIGS. 1 and 2).
The ram assembly, generally indicated at 30 (see FIGS. 2, 3 and 4),
consists of an upper horizontal plate 31 of rectangular shape
generally spanning the area bounded by the four inner corners of
the channels 13 and provided with transverse upwardly turned
flanges 32. From the side edges of the plate 31 depend a pair of
deep skirt plates 33, reinforced by angle braces 34 about the four
edges of the plate 31 and by flanges 35a and 35b along their four
vertical and two bottom edges. Over the four corners formed by the
skirt plates 33 and their flanges 35a are secured nylon glides 36
which slidably bear against the inner corners of the channels 13.
Beneath the upper plate 31 are welded the upper ends of a pair of
trapezoidal shaped supports 37 braced by flanges 38 along their
upright edges and disposed in spaced, back-to-back relation
centrally of the plate 31. Welded to the lower ends of the supports
37 is the upper face of a circular bottom plate 39 having a forward
tab 40 for purposes to be later described and centrally disposed
with respect to the upper ram plate 31. The latter is centrally
bored between the supports 37 to receive a flanged swivel seat 41
for a swivel nut 42 having a squared upper boss 42a, the seat 41
and nut 42 being retained by a flange plate 43 bolted through the
plate 31, the plate 43 having a squared aperture 43a receiving the
boss 42a and so preventing rotation of the nut 42. Through the
latter is threaded a long, Acme type vertical screw 44, its threads
being interrupted at 45 toward its upper end and provided
thereabove with a pair of opposite flats 46 on which is threaded a
nut 47 (see FIG. 2). The latter supports a large, cogged driven
gear 48 whose hub 49 fits the flats 46 to fix the gear 48 relative
to the screw 44. On the hub 49 is placed a sleeve needle bearing 50
which is received in a flanged bushing 51 seated in an aperture 52
in the chassis top plate 14 and bolted thereto between the channel
assemblies 15. Above and below the bushing 51 are interposed a pair
of washer-type needle thrust bearings 53, each sandwiched between a
pair of flat washers 54. Through the bushing 51 extends the upper
end of the screw 44, the latter and thus the entire ram assembly 30
being suspended from the bushing 51 by means of a nut 55 bearing
against the upper-most washer 54. In order to prevent whipping of
the screw 44, its lower end is extended down through an aperture 57
in the ram bottom plate 39 (see FIG. 5). Forward of the ram
assembly 30 a hat-shaped bracket 58 is bolted to the under face of
the chassis top plate 14 from which is vertically suspended an
appropriate electric motor M, the upper end of its drive shaft
carrying a small cogged drive gear 59, the gears 48 and 59 being
connected by a cogged drive belt 60.
Accordingly, as the screw 44 is driven in the appropriate
direction, the entire ram assembly 30 moves downwardly owing to the
swivel nut 42. The four nylon glides 36, which in effect provide a
total of eight bearing faces, fit tightly against the inner corners
of the chassis channels 13 and are heavily greased. The screw 44,
which provides a single axis of thrust centrally disposed with
respect to the ram assembly 30 and parallel to the glides 36,
absorbs most of the resistance encountered by the ram assembly 30
as it descends. Any tendency for it to cock or twist is effectively
resisted and accommodated by the strength of the ram assembly 30,
the extensive length of the eight surfaces of the nylon glides 36
and the substantial lateral spacing of the latter from the axis of
the screw 44. The interrupted thread portion 45 of the screw 44
prevents over-travel of the ram 30 upon its upward movement. The
driven gear 48, which may be of powdered metal or cast from
aluminum or iron, is provided with 84 cogs while the drive gear 59
has 10 to 13 cogs, the motor M being a standard 1/3 hp, 115 VAC
unit of 1,725 rpm.
The removable ram head assembly 90, which is of generally circular
shape, consists essentially of an integral casting 91 having a side
wall formed by peripheral ribbing 92 which undulates radially with
respect to a circle circumscribed thereabout, the ribbing 92 being
extended to provide a forward tab 93 similar to tab 40 of the ram
bottom plate 39. The ribbing 92 is reinforced by reticular ribbing
94 therebetween, the upper ends of the ribbing 92 and 94 and the
upper face of the tab 93 providing faces mating with the lower face
of the ram bottom plate 39. The lower ends of the ribbing 92 and 94
are closed by an end wall whose leading face provides a flat,
compacting surface 95 whose peripheral contour is the same as that
of the ribbing 92 and centrally disposed with respect to the axis
of thrust of the ram drive screw 44. Midway between the top and
bottom of the periphery of the ribbing 92 is formed a laterally
extending, generally circular flange 96 below the level of the tab
93 of substantially the same overall diameter as the ram bottom
plate 39 and concentric therewith. The intersections between
selected ones of the ribbing 94 are enlarged to provide four
rectangularly spaced bolsters 97, centrally disposed with respect
to the head assembly 90, to which is screwed an inverted hat
section plate 98, diametrically aligned with the tab 93. Beneath
the leaves 99 of the plate 98 the respective ribbings 92 and 94 are
relieved, as indicated at 100, in order to permit the leaves 99
slidably to engage a pair of flat spaced ways 101 formed from a
pair of reversely bent metal strips 102 welded to the bottom face
of the ram bottom plate 39 to each side of a diametrical line
through the tab 40 in order to attach the ram head assembly 90 to
the plate 39. The two are releasably retained by a spring loaded
bayonet catch assembly 103 mounted in the tab 40 and engaging a
hole 104 in the tab 93 therebelow. In order to provide clearance
for the lower end of the screw 44 as the head assembly 90 is slid
on and off the way 101, the ribbing 92 and the flange 96 opposite
the tab 93 are relieved at 105, as is the transverse ribbing 94
between the adjacent most pair of bolsters 97 and the corresponding
portion 106 of the plate 98. Finally, to the upper face of the
flange 96 is screwed a neoprene gasket 107 having a circular
perimeter of a diameter somewhat greater than that of the flange
96, all for purposes to be described. Accordingly, by releasing the
catch 103 the ram head assembly 90 can be slid forwardly and
readily removed for cleaning or replacement.
The slide-out mount 120 for the trash container (see FIGS. 2 and 7)
is formed by a rectangular floor pan 121 having shallow side and
rear end walls 122 and a large centrally located, circular aperture
123 therein normally axially aligned with the ram head 90 and
somewhat larger in diameter. To the exterior of the side walls 122
along the floor pan 121 are affixed the outer members 124 of a pair
of three-piece, ball bearing full extension glides 125, of
conventional type, whose stationary members 126 are secured across
the flanges of the chassis channels 13 just above the floor plate
11. The floor pan 121 is also provided with a front wall 127,
extending the full width of the cabinet 17, which is forwardly
stepped to form the cabinet toe space 18 and carries a toe plate
128. A pair of upright, trapezoidal braces 129 welded to the floor
pan 121 and the inner faces of the side and front walls 122 and 127
secure the front wall 127 to the floor pan 121 and the cabinet
front panel 21, carrying the hand grip 22, is secured in turn to
the front wall 127 above the toe plate 128. Two different sized
spring clips 140 are fastened to the inner face of the front wall
127 for purposes to be described. Inwardly of the corners of the
floor pan 121 four flat, container supporting springs 141 extend
radially into the aperture 123. Each spring 141 consists of a
cantilevered arm 142 and a shank 143 terminating in vertically
split tongues 144 formed in the opposite end of the shank 143. The
latter lies atop the floor pan 121 while the tongues 144 engage the
upper and lower faces of the floor pan 121 through a hole 145
through the latter in order to locate the spring 141, its lateral
movement being restrained by a downset tang 146 formed in the shank
143 and engaging another hole 147 in the floor pan 121 (see FIG.
8).
The springs 141 support a trash container assembly 180 consisting
of an outer bucket 181 equipped with handles 182 (or cut-outs) and
fitting the aperture 123 in the floor pan 121. The container
assembly 180 is normally supported on the spring arms 142 above the
chassis floor plate 11 in which position it is just below and
axially aligned with the lower face 95 of the ram head 90 when
fully retracted (see FIG. 2). Within the bucket 181 are nested
first a polyethlene liner 183 and then a disposable plastic bag
184, folded over the top of the bucket 181 and liner 183, having a
circular, corrugated paperboard insert 185 forming a protective
cushion for the bottom of the bag 184. The latter is protected by
three arcuate, overlapping metal shield plates 186 having handles
187 which fit over the rims of the bucket 181, liner 183 and bag
184 (see FIGS. 2 and 9) in order to retain the bag 184 and shield
plates 186 against the wall of the liner 183. The bucket 181 and
liner 183 taper from top to bottom, the interior diameter of the
container 180 at its bottom being substantially equal to the
diameter of the flange 96 of the ram head 90, while its interior
diameter at the top is substantially equal to that of the gasket
107. As a practical working example, the bucket 181 may be formed
from 16 gage galvanized steel with top and bottom outside diameters
of 14-1/2 inches and 14 inches respectively and a height of about
15 inches. The shield plates 186 may be of similar material while
the wall thickness of the liner 183 can be about 0.002-0.005 inch.
The diameter of the flange 96 of the ram head plate 81 may be about
13 inches while the edge of the scalloped perimeter of the ram head
face 95 undulates between three-eighths inch and 1 -1/2 inches from
the edge of the flange 96, the step between the latter and the face
95 being about three-eighths inch. The clearance between the edge
of the flange 96 and the shield plates 186 is thus about
five-sixteenth inch at the top and three-sixteenth inch at the
bottom of the container 180, insuring adequate but not too much
clearance so as neither to jam nor to miss small objects.
When the ram 30 is in its fully retracted position as shown in FIG.
2, the container 180 can be pulled forwardly out of the cabinet 17
on its mount 120, as indicated by the arrow in FIG. 2, by the hand
grip 22 in order for trash to be deposited. When the container 180
is full, the ram 30 is activated and descends to compress the trash
at which time the springs 141 deflect allowing the container 180 to
sink through the aperture 123 until its bottom sits firmly upon the
chassis floor plate 11. The scalloped perimeter of the lower face
95 of the ram head plate 91 not only reduces the area and thus
increases the pressure applied by the face 95 but also tends,
together with the step between the face 95 and the flange 96 above,
to apply a multitude of random, downwardly directed forces on
bottles and the like lying about the wall of the container 180 in
order to provide effective breakage and to reduce or eliminate
lateral forces on the side wall of the container 180. At the same
time, the flange 96 avoids missing small objects and yet minimizes
clearance between the ram head plate 91 and the wall of the
container 180. The arcuate shield plates 186 protect the sides of
the disposable bag 184 from tearing during the compacting stroke,
the bags 184 being readily available standard items so that no
specially formed or shaped bags are necessary; most any bag which
generally fits within the container 180 will do the job. When the
shield plates 185 are withdrawn, the bag 184 with the trash
compressed therein can be readily removed from the liner 183 owing
both to the absence of the shield plates 186 and the overall taper
of the container 180. The polyethylene liner 183 is preferably
included to insure cleanliness of the interior of the bucket 181
since the latter is necessarily quite heavy to lift out for
cleaning. In addition, the liner 183 also serves to protect the
walls of the bucket 181 should the shield plates 186 not be used
for some reason. In that case, too, should the bag 184 tear or the
liner 183 become damaged, the latter can be much more readily
cleaned or replaced than the heavy bucket 181. The ram head gasket
107, which bears against the shield plates 186, acts as a splash
shield, while the clips 140 on the container mount 120 are for
different sized spray cans of deodorant or disinfectant to be used
on trash deposited in the container 180 or after its compaction and
removal.
Turning now to FIGS. 10A - E, the electrical control circuit for
the compactor will now be described. One side L1 of the 115 VAC
power supply line L is connected directly to one end of the run
windings R of the motor M through a typical thermal overload switch
T within the motor M. The other side L2 is connected in series with
four s.p.s.t. switches SW1, SW2, SW3 and SW4, themselves also
connected in series. SW1 is a safety interlock switch biased
normally open and located in a box 190 supported by a bracket 191
at the extreme rear of the chassis floor plate 11 adjacent its
right hand corner (as viewed from the front) so that the box 190 is
elevated above the rear wall 122 of the slide-out mount 120 (see
FIGS. 2, 3 and 7). SW1 is operated by a horizontal pin 192
projecting rearwardly from an upstanding bracket 193 (see FIG. 7)
secured to the rear wall 122 of the slide-out mount 120 which
passes through a hole in the front face of the box 190 and closes
SW1 only when the mount 120 is pushed fully in. SW2 is a key
operated safety switch and SW3 a manually operated ram stop switch,
both mounted on the front control panel 19. SW4 is a ram top limit
switch biased normally closed and located under the chassis top
plate 14 on a bracket 194 (see FIG. 4) in one of its forward
corners to be opened by the forward flange 32 of the upper ram
plate 31 when the ram 30 is in its uppermost position. A s.p.s.t.
momentary start switch SW5 is wired in parallel with SW4 and also
located on the control panel 19. The downstream side of SW4 is
connected to the other end of the run windings R and to one of each
pair of the alternate contacts of a d.p.d.t. ram directional switch
SW6 located beside SW4 on the bracket 194 and operated in the same
manner, the two circuit-making members of SW6 being moved by the
flange 32 of the upper ram plate 31 to the position shown in FIG.
10A and biased to the position shown in FIG. 10B. The other of each
pair of alternate contacts of SW6 are both connected to the line L1
at the run windings R. One of the circuit making members of SW6 is
connected in series with one end of the start windings S of the
motor M through a start capacitor C and the other circuit making
member of SW6 to the other end of the start windings S through a
centrifugal s.p.s.t. switch SW7 within the motor M and normally
closed when the motor M is below a predetermined run speed. The
operating sequence of the compactor is then as follows:
As shown in FIG. 10A, the ram 30 is at rest at the top of its
stroke and the container mount 120 pushed fully in, whereby the
safety interlock switch SW1 is closed, the top limit switch SW4 is
open and the ram directional switch SW6 is in the position
illustrated; the key switch SW2, the manual stop switch SW3 and the
centrifugal switch SW7 are all closed. To activate the ram 30, the
momentary start switch SW5 is first closed, as shown in FIG. 10B,
completing the circuit from L2 to the run windings R and to the
start windings S through SW6, the direction of current flow through
the latter windings being indicated by the arrows in FIG. 10B. The
ram 30 thus starts to descend, permitting the top limit switch SW4
to close and maintain the circuit to the start windings S of the
motor M, whereupon SW5 can be released, all as shown in FIG. 10C.
After the motor M is up to speed the centrifugal switch SW7 opens
the circuit through the start windings S, the motor M thereafter
being operated by the run windings R only, and as the ram 30
further descends the directional switch SW6 moves to its alternate
position preparatory for reversing the direction of current flow
through the start windings S. When the ram 30 has compressed the
trash in the container 180 to a point where its resistance slows
the motor M sufficiently, at which point the ram 30 is exerting
about 3,200 lbs. of force upon the trash, the centrifugal switch
SW7 recloses to re-energize the start windings S, through which the
current flows in the reverse direction as shown by the arrows in
FIG. 10D owing to the previous movement of the directional switch
SW6, thus reversing the motor M and starting the ram 30 upward. As
the motor M gets up to speed, the centrifugal switch SW7 reopens,
as shown in FIG. 10E, and the ram 30 continues to rise until the
flange 32 of the upper ram plate 31 opens the top limit switch SW4,
thus breaking the circuit to the motor M and halting the ram 30. At
the same time, the directional switch SW6 is returned to its
original position and the centrifugal switch SW7 recloses, whereby
the circuit is restored to the condition shown in FIG. 10A, ready
for another compacting cycle. Travel of the ram 30 up or down can
be halted by opening the manual stop switch SW3 which breaks the
circuit from L2 to the motor M under all conditions. Reclosing SW3
will cause the ram 30 to return to its initial, upper position,
regardless of in which direction it had been going, owing to the
fact that in either event SW6 is in the motor reversing position
shown in FIGS. 10C-10E. The key safety switch SW2 is incorporated
so that the compactor can be locked up to protect children or to
avoid unauthorized use inasmuch, as is apparent, the compactor is
inoperative until SW2 is closed. The safety interlock switch SW1
prevents any operation of the ram 30 unless the container mount 120
is fully pushed in.
Should there be no trash in the container 180, or even should the
latter have been entirely removed for some reason, the compactor
can still be operated so long as the container mount 120 is pushed
in. In theory, the ram 30 could simply descend until it contacts
the bottom of the container 180 or the chassis floor plate 11, as
the case may be, and then reverse in the foregoing manner, all
without harm. Hence, it is theoretically unnecessary to employ any
device for measuring the resistance encountered by the ram 30 in
order to reverse it or to limit the compacting stroke to a
predetermined distance above the bottom of the container 180. In
practice, however, in order to keep the length of the ram drive
screw 44 such that the overall height of the cabinet 17 permits it
to be built-in under a typical kitchen counter or the like, the
length of the stroke of the ram 30 must often be restricted so that
it does not "run-off" the screw 44 before it would otherwise
contact the chassis base plate 11 or the bottom of the container
180, as the case might be. This is required in the case of the
embodiment shown, and for that purpose four stops 195 (see FIG. 7)
are welded in the corners of the channels 13 which engage the
flanges 35b of the ram 30 when the compacting face 95 of the ram
head 90 has descended to a position equivalent to about 1-1/2
inches from the bottom of the container 180, thus halting the ram
30 and causing it to reverse in the manner explained above
regardless of whether the container 180 is empty or is removed from
its mount 120. Even so, the degree of compaction is still uniform
and for all practical purposes independent of the amount of trash
in the container 180.
Though the present invention has been described in terms of a
particular embodiment, being the best mode known of carrying out
the invention, it is not limited to that embodiment alone. Instead,
the following claims are to be read as encompassing all
modifications and adaptations of the invention falling within its
spirit and scope.
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