Abstrict A waste container crusher particularly adapted for crushing automotive
type oil filters or other structurally rigid disposables containing
hazardous waste has a housing with an open bottom which is closed
off by an anvil plate. The anvil plate slideably receives three
equiangularly spaced posts which are secured to a roof plate at
the top of the housing, above the anvil plate. Nuts on the posts
support the anvil plate below the roof plate, so that the anvil
plate is suspended from the roof plate by the posts. The roof plate
is secured to a hydraulic cylinder which produces a 10 ton driving
force for a platen guided by the posts to crush a container placed
on the anvil plate below the platen. In the anvil plate, four blind
bores in a rectangular pattern in the top surface intersect a central
blind bore extending from the bottom surface, and a smaller central
through-bore provides communication between the lower central blind
bore and the top of the anvil plate. In one embodiment, a pneumatic-hydraulic
control circuit is provided in which the hydraulic cylinder is driven
until an air powered hydraulic pump stalls. In an alternate embodiment,
an electro-hydraulic control circuit drives the hydraulic cylinder
according to a timed cycle.
Claims We claim:
1. A waste container crusher, comprising:
a housing having a closeable door;
an anvil plate for supporting a container to be crushed within
said housing;
a platen for crushing said container against said anvil plate;
a hydraulic cylinder for driving said platen against a container
to be crushed supported on said anvil plate within said housing,
said cylinder having a cylinder port;
an air powered hydraulic pump having a pneumatic port and a hydraulic
port, said pump providing a supply of hydraulic fluid at said hydraulic
port which can be compressed to a pressure limit which is proportional
to a pressure of a compressed air supply provided at said pneumatic
port;
a main air valve having a first port and a second port, said valve
blocking said first port and venting said second port in an off
state and connecting said first and second ports in an on state;
means communicating said hydraulic port and said cylinder port;
means communicating said second port of said main air valve and
said pneumatic port;
means for providing a supply of compressed air at a certain pneumatic
pressure to said first port of said main air valve; and
means for changing said main air valve between said on and off
states including an interlock control actuated by closing said door
such that said main air valve is turned on when said door is closed
and is turned off when said door is opened;
wherein when said door is closed, said pump drives said cylinder
to said pressure limit, whereat said pump stalls, and said pump
maintains the pressure of said cylinder at said pressure limit after
said pump stalls until said door is opened.
2. A waste container crusher as in claim 1 wherein said interlock
control is a pneumatic valve which is shifted upon closing said
door to pressurize a pilot port of said main air valve to thereby
turn said main air valve on.
3. A waste container crusher as in claim 1 further comprising
a pneumatically actuated dump valve in communication with said pump
hydraulic port so as to vent said pump hydraulic port to a reservoir
tank when said door is opened.
4. A waste container crusher as in claim 1 wherein said air powered
hydraulic pump is a reciprocating pump.
5. A waste container crusher as in claim 1 further comprising:
a dump valve, said dump valve having a first port, a second port
and a pneumatic pilot port;
a reservoir tank of hydraulic fluid;
means communicating said dump valve first port and said cylinder
port;
means communicating said dump valve second port and said reservoir
tank;
means communicating said dump valve pneumatic pilot port and said
pump pneumatic port;
wherein in the on state of said main air valve said dump valve
first and second ports are blocked and in the off state of said
main air valve said dump valve first and second ports are placed
in communication.
6. A waste container crusher, comprising:
a housing having a closeable door;
an anvil plate for supporting a container to be crushed within
said housing;
a platen for crushing said container against said anvil plate;
a hydraulic cylinder for driving said platen against a container
to be crushed supported on said anvil plate within said housing,
said cylinder having a cylinder port;
an air powered hydraulic pump having a pneumatic port and a hydraulic
port, said pump providing a supply of hydraulic fluid at said hydraulic
port which can be compressed to a pressure limit which is proportional
to a pressure of a compressed air supply provided at said pneumatic
port;
a main air valve having a first port and a second port, said valve
blocking said first port and venting said second port in an off
state and connecting said first and second ports in an on state;
means communicating said hydraulic port and said cylinder port;
means communicating said second port of said main air valve and
said pneumatic port;
means for providing a supply of compressed air at a certain pneumatic
pressure to said first port of said main air valve;
means for changing said main air valve between said on and off
states including an interlock control actuated by closing said door
such that said main air valve is turned on when said door is closed
and is turned off when said door is opened;
wherein when said door is closed, said pump drives said cylinder
to said pressure limit, whereat said pump stalls;
a dump valve, said dump valve having a first port, a second port
and a pneumatic pilot port;
a reservoir tank of hydraulic fluid;
means communicating said dump valve first port and said cylinder
port;
means communicating said dump valve second port and said reservoir
tank;
means communicating said dump valve pneumatic pilot port and said
pump pneumatic port;
wherein in the on state of said main air valve said dump valve
first and second ports are blocked and in the off state of said
main air valve said dump valve first and second ports are placed
in communication;
wherein said means for changing said main air valve between said
on and off states includes a main air valve pneumatic pilot port
of said main air valve, and wherein said interlock control includes
an interlock valve which is actuated by closing said door, said
interlock valve having a first port and a second port, said first
and second ports being placed in communication by closing said door
and said first port being normally blocked and said second port
being normally vented in the open position of said door;
means connecting said main air valve pilot port and said interlock
valve second port; and
means for providing compressed air to said main air valve first
port and said interlock valve first port;
wherein closing said door actuates said interlock valve to change
said main air valve to said on state and opening said door deactuates
said interlock valve to return said main air valve to said off state.
7. A waste container crusher, comprising:
an anvil plate for supporting a container to be crushed;
a platen for crushing said container against said anvil plate;
a hydraulic cylinder for driving said platen against a container
to be crushed supported on said anvil plate, said cylinder having
a cylinder port;
an air powered hydraulic pump having a pneumatic port and a hydraulic
port, said pump providing a supply of hydraulic fluid at said hydraulic
port which can be compressed to a pressure limit which is proportional
to a pressure of a compressed air supply provided at said pneumatic
port;
a main air valve having a first port, a second port and a pilot
port, said valve being normally biased to block said first port
and vent said second port in an off state and being shiftable against
said bias when said pilot port is pressurized to connect said first
and second ports in an on state;
a dump valve having a first hydraulic port, a second hydraulic
port and a pneumatic pilot port, said dump valve being normally
biased to provide communication between said first hydraulic port
and said second hydraulic port and to cut off said communication
when said pneumatic pilot port is pressurized;
a reservoir tank of hydraulic fluid;
means communicating said hydraulic port, said cylinder port and
said first hydraulic port of said dump valve with one another;
means communicating said second port of said main air valve, said
pneumatic port and said pilot port of said dump valve;
means communicating said second hydraulic port of said dump valve
and said reservoir tank with one another;
an interlock valve having a first port, a second port and an actuator,
said interlock valve being normally biased to block said first port
and vent said second port and being shiftable by said actuator against
said bias to communicate said first and second ports with one another;
means for providing compressed air to said first ports of said
main air valve and said interlock valve;
means providing communication between said second port of said
interlock valve and said pilot port of said main air valve; and
a housing for enclosing said container when said container is being
crushed, said housing having a door which when closed actuates said
actuator of said interlock valve;
wherein closing said door shifts said interlock valve to pressurize
said pilot port of said main air valve to shift said main air valve
to pressurize the pneumatic port of said pump and the pilot port
of said dump valve to drive said pump and close said dump valve
until the first to occur of either said pump stalling or said door
opening.
Description FIELD OF THE INVENTION
This invention relates to devices for crushing waste containers
in a manner to prepare them for recycling, and particularly to a
device specially adapted for crushing disposable oil filters.
BACKGROUND OF THE INVENTION
Disposable oil filters, for example of the type commonly used on
automotive engines, and other similar disposable items, have created
a disposal problem. These items typically occupy a relatively large
volume for the amount of solid materials which they contain and
may contain an environmentally hazardous liquid, such as waste oil.
In some parts of the country, waste oil filters are now mandatorily
recycled. However, whether oil filters are recycled or not, it is
desirable to reduce their volume by collapsing or crushing them
and to drain them of the majority of environmentally hazardous liquids
which they contain.
To accomplish this purpose, a relatively large force is required
to crush the oil filter axially. As is well known, oil filters of
the automotive type are typically in the general shape of a cylindrical
can. Crushing is usually accomplished by reducing the length of
the can along the cylinder axis. For example, a four or five inch
tall oil filter may typically be crushed to a height of one inch
or less without appreciably changing the diameter of the filter.
A large force is required because the diameter of the filter is
typically about 3 to 4 inches and the filter is typically made of
structurally rigid materials such as steel.
As a container such as an oil filter is crushed in this manner,
the majority of liquid within the container is squeezed out. Therefore,
a device for crushing such containers must be able to drain the
liquids away from the container as the container is being crushed.
These functions must be combined in a low cost, reliable and easy
to use crusher.
SUMMARY OF THE INVENTION
The invention provides an improved waste container crusher particularly
adapted for crushing automotive type oil filters or other structurally
rigid disposables containing hazardous waste. The crusher has a
roof plate, an anvil plate located a predetermined spacing below
the roof plate, a housing enclosing the space between the roof and
anvil plates. Each of a plurality of posts has one end secured in
one of the plates and an opposite end slideably received in the
other of the plates. The posts are angularly spaced apart about
a longitudinal axis which is generally parallel to the posts. Means
are provided on the slideably received ends of the posts for maintaining
a predetermined spacing between the plates. A platen is slideably
mounted on the posts for reciprocable movement along the longitudinal
axis. Power means is fixed to the roof plate for driving the platen
toward the anvil plate, and control means is provided for actuating
the power means to crush a waste container placed on the anvil plate
between the platen and the anvil plate when the recycler is operated.
In this construction, the posts guide the platen and also act as
structural supports. The posts are placed in tension to bear substantially
the entire load of the power means as the crusher is operated to
crush a container. Since one end of each post is slideably received
in one of the plates, the anvil plate is suspended from the roof
plate so that it may realign itself under the roof plate as a container
is being crushed. In this manner, undesirable side loading on the
posts and the power means is substantially reduced in a compact,
reliable and economical unit.
In a preferred form, the upper ends of the posts are secured in
the roof plate and the lower ends of the posts are slideably received
in the anvil plate. The housing is rigidly secured to one of the
plates and not to the other plate. Thereby, distortions in the housing
are prevented which may otherwise occur upon operating the crusher
and the posts may also be used to support the roof plate over the
anvil plate when the crusher is not in use.
In an especially useful form, three posts spaced 120.degree. apart
are provided. This allows a symmetrical load distribution on the
platen to help prevent side loading on the power means, especially
when a container is placed in the crusher not aligned with the longitudinal
axis of the crusher.
In a preferred aspect, the anvil plate is provided with multiple
holes which drain into a single hole. The multiple holes include
a central hole substantially coaxial with the longitudinal axis
and at least one hole offset from the longitudinal axis. In the
most preferred form, four blind bores are formed in a top surface
of the anvil plate in a generally rectangular pattern centered on
the longitudinal axis, a central hole is formed in the top surface
of the anvil plate substantially coaxial with the longitudinal axis,
and a blind bore is formed in the bottom surface of the anvil plate
which intersects the four holes and is in communication with the
central hole.
In one form, the control means includes a compressed air powered
hydraulic pump, an air interlock valve and the housing has a closeable
door. The interlock valve is actuated by closure of the door to
initiate operation of the air powered hydraulic pump, which is operated
until it stalls. Thereby, a low cost and reliable non-electric control
system is provided for operating the crusher.
In another form, the control means includes an electric powered
hydraulic pump and an electric interlock switch. As in the pneumatic
control system, the interlock switch is actuated by closure of the
door to initiate operation of the electric powered hydraulic pump,
which drives the platen to crush the container. However, this control
system includes a timer for limiting the duration of the crushing
stroke.
Other features and advantages of the invention will be apparent
from the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation view of a waste container crusher of
the present invention with portions broken away;
FIG. 2 is a right side elevation view of the crusher of FIG. 1
with a portion broken away;
FIG. 3 is a sectional view taken along the plane of the line 3--3
of FIG. 1;
FIG. 4 is a top plan view of an anvil plate for the crusher of
FIG. 1;
FIG. 5 is a sectional view taken along the plane of the line 5--5
of FIG. 4;
FIG. 6 is a schematic view of a pneumatic-hydraulic control circuit
for the crusher of FIG. 1;
FIG. 7 is a sectional view of a modified porting arrangement for
a pump for the pneumatic-hydraulic control circuit of FIG. 6;
FIG. 8 is a sectional view of a dump valve for the pneumatic-hydraulic
control circuit of FIG. 6;
FIG. 9 is a fragmentary view similar to FIG. 2 but for an electro-hydraulic
powered alternate embodiment; and
FIG. 10 is a schematic view of a control circuit for the electro-hydraulic
embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2 a waste container crusher 10 of the
present invention is illustrated. The waste container crusher 10
of the preferred embodiment is particularly adapted to crush oil
filters of the automotive type. These filters are well known, are
usually in the form of a cylindrical can which is about 3 to 6 inches
tall as measured along its cylinder axis and usually about 3 to
5 inches in diameter.
The crusher 10 is usually used for crushing such containers along
their cylindrical axis to effect a material decrease in length and
corresponding increase in density of the container. For example,
a 5 inch tall filter can be compressed to a height of approximately
1 inch or less. In this process, the great majority of oil inside
the filter is squeezed out and drained away from the filter, as
hereinafter described.
The crusher 10 includes a housing 12 made of relatively light gauge
sheet metal and having a top 14 left side 16 right side 18 a
front side 20 and a rear side 22. The bottom of the housing 12 is
open but closed off by an anvil plate 24. The anvil plate 24 may
be sealed with a suitable caulking material (not shown) to the housing
12 so as to prevent leakage, but otherwise is not directly secured
to the housing 12.
The front side 20 of the housing 12 has an opening 26 which is
covered in operation by a door 28. The door 28 is hinged at 30 to
the front side 20 of the housing 12 and includes a latch 32. The
latch 32 is rotatable and has a helical wire 34 which cams on the
rear surface of the front side 20 to pull the door 28 tightly against
the front side 20 when the latch 32 is rotated clockwise as viewed
in FIG. 1.
Referring also to FIG. 3 three support posts 36 equiangularly
spaced at 120.degree. about a common center 38 support a roof plate
40 inside the housing 12 at the top of the housing 12. The housing
12 may be secured to the roof plate 40 by fasteners or other appropriate
means (not shown).
Each of the posts 36 has a threaded top end 42 (only one shown)
which is threaded into the roof plate 40 to secure the roof plate
40. Lower end 44 of each post 36 is slideably received within bores
46 of anvil plate 24. Below the anvil plate 24 the lower ends 44
are threaded and nuts 48 are received thereon which abut the bottom
of the anvil plate 24 to support the anvil plate 24 at the bottom
of the housing 12 spaced from the roof plate 40. The lower tips
of the posts 36 have flats 50 to enable tightening the posts 36
to the roof plate 40 and for holding the posts 36 rotatably stationary
when assembling the nuts 48.
The pattern of posts 36 is arranged to provide a large opening
at the front of the housing 12 so that a container to be crushed
can easily be placed upon the anvil plate 24. Also, it may be desirable
to have the rear-most post 36 extend somewhat above the top of the
housing 12 so that a suitable bracket can be attached to the top
of the rear-most post 36 and also to the bottom for mounting the
crusher 10 to a wall or other suitable vertical support.
The top 14 of the housing 12 has a central bore, as does the roof
plate 40. The central bore of the roof plate 40 is threaded at 52
and a hydraulic cylinder 54 is threaded into it to be rigidly secured
therein. The hydraulic cylinder 54 has a piston shaft 56 threaded
into a coupling 58 which secures a platen 60 by means of a stud
62 which is threaded into the lower end of the coupling 58 and into
the platen 60 at 61. The platen 60 is circular as shown in FIG.
3 and has three equiangular spaced through-bores 64 in which the
posts 36 are received. The posts 36 are hard chrome plated and a
bronze bearing 66 is received with a press fit within each of the
through bores 64. The lumen of the bronze bearing 66 is coated with
a lubricious material, such as a polytetraflouroethylene resin,
to substantially reduce friction between the platen 60 and the posts
36. Bearings 66 found suitable are commercially available from Garlock
Bearing, Inc. of Thorofarey, N.J. under the trade designation type
D-U. A smooth sliding fit is thereby achieved between each post
36 and the corresponding bearing 66 so that the posts serve to
guide the platen 60 as it reciprocates up and down. The posts 36
also prevent side loading on the cylinder 54 which may otherwise
result if a container to be crushed is not concentrically aligned
with the center 38 as it rests on the anvil plate 24.
The posts 36 serve not only to guide the platen 60 and prevent
undesirable side loading on the piston shaft 56 and hydraulic cylinder
54 but also serve as structural supports for the crusher 10. The
crusher 10 as previously described may be supported by hanging
from the top of the rear-most post 36 and supporting the rear-most
post 36 from the bottom, or may be supported from the bottom of
the nuts 48 for example on a table top having holes through which
the lower ends 44 of the posts 36 would extend so that the nuts
48 could rest on the table top. When the crusher 10 is not in use,
the posts 36 serve to support the roof plate 40 and hydraulic cylinder
54 above the anvil plate 24 with the anvil plate 24 simply resting
on top of the nuts 48. When in use, the force of the hydraulic cylinder
54 10 tons in the preferred embodiment, acts to try to separate
the anvil plate 24 from the roof plate 40. Therefore, when in use
the posts 36 serve to support the spacing between the anvil plate
24 and roof plate 40 to prevent them from separating. Thereby, the
10 ton load exerted by the cylinder 54 is born by the three posts
36 acting under a tensile loading.
Referring to FIGS. 4 and 5 the anvil plate 24 is provided with
a special arrangement 63 of holes to allow for the proper draining
of an automotive type oil filter while the filter is being crushed.
A rectangular pattern of four equiangularly spaced blind bores 70
is provided in the top surface of the anvil plate 24. A fitting
hole 72 extends from the lower surface of the anvil plate 24 upwardly
and is of a diameter to intersect the holes 70 thereby creating
a path of communication from each hole 70 into the fitting hole
72. Fitting hole 72 does not extend all the way through the anvil
plate 24 but a smaller central through-bore 72 is provided in the
center of the holes 70 which extends from the top surface of the
anvil plate 24 through to the fitting hole 72.
In use, an oil filter is placed with its open end down on top of
the anvil plate 24. Typical oil filters have a relatively large
central hole with a circular pattern of smaller holes spaced around
the larger hole and with a ring of metal between the circular pattern
of smaller holes and the larger central hole. The oil filter is
placed on top of the anvil plate 24 with its larger central hole
generally aligned with the central hole 74. Thereby, the central
hole 74 and holes 70 provide passages for the escape of oil through
the central hole of the filter as well as through the smaller peripheral
holes. A central drain passage as well as peripheral drain passages
are provided because the ring of metal between the circular pattern
of smaller holes and the larger central hole of an oil filter can
create a seal against the anvil plate 24 when the filter is being
crushed. This arrangement of drain holes has been found to provide
adequate draining while at the same time providing sufficient support
against the forces generated in crushing an automotive type oil
filter. The fitting hole 72 is tapped to receive a standard hose
connection fitting so that the waste oil squeezed from the filter
can be removed to an appropriate reservoir for subsequent disposal
or further possessing.
A pneumatic-hydraulic control system 78 for the crusher 10 includes
a port 79 for connection to a source of compressed air, an interlock
valve 80 a main air valve 82 an air powered hydraulic pump 84
and a dump valve 86. The purpose of the control system is to automatically
operate the hydraulic cylinder 54 to crush a container placed beneath
the platen 60.
The interlock valve 80 is mounted on the rear surface of the front
side 20 of the housing 12 and has a push type spring return actuator
88 which is depressed by the door 28 as the latch 32 is turned clockwise
as viewed in FIG. 1. Also referring to FIG. 6 suitable pneumatic
tubing connects a first port 80a of the interlock valve 80 to the
air supply and a second port 80b to a pilot port 82c of a spring
biased main air valve 82. When the interlock valve 80 is actuated,
it is shifted against its spring force to shift the main air valve
82 against its spring force, which place the first and second control
ports 82a and 82b of the valve 82 in communication. Since the main
air valve 82 has control port 82a connected to the air supply and
control port 82b connected to a pneumatic port 84a of the air powered
hydraulic pump 84 pressurizing the valve 82 pilot port 82c provides
air pressure from the air supply to drive the air powered hydraulic
pump 84.
The air powered hydraulic pump 84 used in the preferred embodiment
is capable of producing a hydraulic pressure of approximately 10000
psi given an inlet air pressure of approximately 80 psi. Such pumps
are well known and one such pump is described in U.S. Pat. No. 3041975
issued Jul. 3 1962 the disclosure of which is hereby incorporated
by reference. The pump described in U.S. Pat. No. 3041975 is a
reciprocating type pump in which a relatively large surface area
pneumatic piston drives a relatively small diameter hydraulic piston,
and the pump includes a reservoir of hydraulic fluid. A suitable
pump like that described in U.S. Pat. No. 3041975 is commercially
available from Applied Power, Inc., Butler, Wis. under the trade
designation PA-133. The valves 80 and 82 and cylinder 54 are also
all well known commercially available items.
The hydraulic port 84b of the hydraulic pump 84 is routed to a
port 54a of the hydraulic cylinder 54 and to a first control port
86a of the dump valve 86. The cylinder 54 has only one port because
it is advanced under pressure and returned by a low force spring.
In the preferred embodiment, the hydraulic cylinder 54 is capable
of producing a 10 ton force given a 10000 psi hydraulic pressure.
Thereby, with an 80 psi air supply pressure, a force of 10 tons
is produced for crushing waste containers in the crusher 10.
The dump valve 86 is for relieving pressure from the hydraulic
cylinder 54 upon the completion of a crushing cycle. In addition
to having a first control port 86a in communication with the hydraulic
port of the pump 84 the hydraulic dump valve 86 has a pilot port
86c in communication with the pneumatic port 84a of the pump 84
and a second control port 86b connected to tank 90. Thus, when valve
82 is shifted so as to provide pneumatic pressure to the pump 84
the dump valve 86 is shifted so as to block the flow of hydraulic
fluid from the pump 84 to tank 90 which may conveniently be provided
in the pump 84 as hereinafter discussed. When the pilot pressure
is exhausted from the dump valve 86 which is what happens when
valve 82 shifts to its normal "off" position, the valve
86 returns to its normal position shown in FIG. 6 so that the cylinder
54 and the hydraulic port 84b of the pump 84 are vented to tank
90.
In operation of the waste container recycler 10 a waste container
containing liquid is placed open end down generally centered on
the hole 74. The door 28 is then shut and the latch 32 rotated clockwise
as viewed in FIG. 1 to pull the door 28 tightly shut. This action
actuates the interlock valve 80 which provides pilot pressure to
the main air valve 82 to shift the main air valve 82 so as to provide
supply pressure to the air powered hydraulic pump and pilot pressure
to the dump valve 86. The hydraulic output of the pump 84 is thereby
provided to the cylinder 54 to advance the piston shaft 56. This
provides a 20000 pound force on the waste container placed beneath
the platen 60.
When the container has been crushed to the force limit of the cylinder
54 the output hydraulic pressure of the pump 84 reaches its capacity
when the air pressure acting on the piston within the pump 84 is
no longer able to overcome the hydraulic pressure which the pump
has developed. When this occurs, the pump 84 stalls and holds the
output pressure being exerted on the cylinder 54. Only when the
door 28 is opened is the force exerted by the platen 60 on the container
released. When the door 28 is opened, the interlock valve 80 is
returned to the position shown in FIG. 6 by its return spring to
vent the pilot pressure on the main air valve 82 to exhaust. This
shifts the main air valve back to the position shown in FIG. 6 under
the action of the main air valve return spring, which vents the
pneumatic port of the pump 84 and the pilot pressure of the dump
valve 86 to exhaust. Venting the dump valve 86 pilot pressure to
exhaust opens up the pump 84 hydraulic output and the cylinder 54
pressure to tank 90 which allows the cylinder 54 to return the
platen 60 to near the top of the housing 12 under the action of
the cylinder return spring.
It is noted that if a hydraulic pump 84 like the pump disclosed
in U.S. Pat. No. 3041975 is used, it can be conveniently modified
as shown in FIG. 7 to provide the connection of the dump valve 86
back to tank. In this regard, in FIG. 7 the reference numerals
93 94 and 95 refer to the same items as in FIGS. 7 and 8 of U.S.
Pat. No. 3041975 namely, bore 93 release passage 94 which is
in communication with the hydraulic output of pump 84 and release
passage 95 which is in communication with the reservoir tank of
pump 84.
Referring to FIG. 7 in the preferred modification, the components
occupying bore 93 described in U.S. Pat. No. 3041975 are replaced
with a plug disk 98 and a nipple 100. The interface between passage
94 and bore 93 is sealed off by plug disk 98 which is held in place
with nipple 100. Nipple 100 is threaded into the bore 93 and sealed
therein by O-ring 102. Nipple 100 has an axial bore 104 in communication
with one or more transverse bores 106. Thereby, axial bore 104 communicates
with the tank of the pump 84 via bores 106 and passage 95.
FIG. 8 depicts a preferred form of dump valve 86. The dump valve
86 has a valve block 110 in which a pilot cavity 112 and passageways
114 116 and 118 are formed. In FIG. 8 the passageway 118 is shown
rotated into a plane which is 90.degree. from its actual position
for illustrative purposes. Passageway 114 is connected to the port
54a of cylinder 54 passageway 116 is connected to the hydraulic
port 84b of the pump 84 and passageway 118 which corresponds to
port 86b, is connected to the nipple 100 to be in communication
with axial bore 104 so that passageway 118 is in communication
with the reservoir tank of the pump 84. Passageway 115 which corresponds
to port 86a, opens into the intersection of passageways 114 and
116. A plug 120 is provided in the valve block 110 is sealed therein
with an O-ring seal 122 and is held in place by a spring clip 124.
A piston 126 is sealed against the pilot cavity 112 by an O-ring
128 and held biased against the plug 120 by spring 130. Pin 132
projects from piston 126 and normally holds ball 134 against a seat
136 when the pilot cavity 112 is pressurized. In this regard, the
plug 120 has a central threaded hole 138 which corresponds to port
86c, which is for connection to communicate with the pneumatic port
84a of the pump 84. The face of piston 126 is sized such that at
80 psi air pressure in the pilot cavity 112 sufficient force will
be generated to hold the ball 134 against hardened seat 136 at 10000
psi hydraulic pressure in passageway 116.
Referring to FIGS. 9 and 10 a electro-hydraulic control system
148 for a crusher of the invention is disclosed as an alternate
to the pneumatic-hydraulic control system 78. Referring to FIG.
9 the interlock valve 80 is replaced with an interlock switch 150.
In addition, the main air valve 82 air powered hydraulic pump 84
and the dump valve 86 are replaced by the electrohydraulic control
system 148. The control system 148 is powered by 115 volts AC power
and has an electric powered hydraulic pump 152 a first relay 154
a second relay 156 a timer 158 a transformer 160 a switch 162
and a thermal switch 164 all of which are well-known commercially
available components.
From source 166 ground lead 168 is connected to motor 152. Power
lead 170 is connected to one terminal of the 115 volt side of transformer
160 and, via plug 172 to one of the power terminals of the pump
152. Power lead 174 is connected via plug 172 to one terminal of
thermal switch 164 which is normally closed and provided for thermal
protection of the pump 152. The other terminal of thermal switch
164 is connected via plug 172 to the common terminal of pump switch
162 and the normally off terminal of switch 162 is connected to
the other terminal on the 115 volt side of the transformer 160 and
to a normally open terminal on the first relay 154. The common terminal
on the first relay 154 is connected via plug 172 to the other power
terminal of the pump 152.
The transformer 160 steps down the 115 volts AC to 24 volts AC.
One of the 24 volt terminals of transformer 160 is connected to
interlock switch 150 which is normally open, and the other terminal
of the switch 150 is connected to the input terminal of timer 158
and to the common terminal of the second relay 156. The timer 158
is a solid state timer, commercially available from Artisan Industries
of Parsippaney, New Jersey, Part No. 438U. The timer 158 has a resistor
178 the value of which determines the timing period. The timing
period begins when the timer 158 senses a signal at its input terminal,
and at the end of the timing period the signal is passed through
to the timer 158 output terminal, which is connected to one side
of the coil for the second relay 156. The other side of the coil
of the second relay 156 is connected to the other power terminal
on the 24 volt side of the transformer 160 which is also connected
to one side of the coil of the first relay 154. The other side of
the coil of the first relay 154 is connected to the normally closed
terminal of the second relay 156.
In operation, the pump switch is turned on, but this does not initiate
the beginning of a crushing cycle. First, a filter is placed beneath
the platen 60 with its open end down as previously described. Then,
the door 28 is closed as previously described, which actuates interlock
switch 150. Assuming that the thermal switch 164 has not been actuated,
when the interlock switch 150 is closed, the first relay 154 is
energized and timing by timer 158 begins. Energizing relay 154 starts
pump 152 which provides hydraulic fluid under pressure to drive
hydraulic cylinder 54.
For the duration of the timing period, typically 30 seconds, the
platen 60 is driven downwardly by hydraulic cylinder 54 to crush
the container placed beneath the platen 60. When the timer 158 times
out, second relay 156 is energized which de-energizes the first
relay 154. This turns the pump 152 off, which has the effect of
depressurizing the hydraulic cylinder 54 so that the platen 60 lifts
under the influence of the return spring of the hydraulic cylinder
54. A new cycle cannot be initiated until the door 28 is opened.
When the door 28 is opened, interlock switch 150 opens, which turns
off power to the timer 158 to reset the control circuit to be ready
for the initiation of the next crushing cycle.
Preferred embodiments of the invention have been described. Many
modifications and variations of the preferred embodiments will be
apparent to those of ordinary skill in the art, but which will still
be within the spirit and scope of the invention. Therefore, the
invention should not be limited by the scope of the preceding description
of the preferred embodiments, but only by the claims which follow.
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