Note: Descriptions are shown in the official language in which they were submitted.
~;22913Çi~
FINGER PRESSURE ACTABLE DUMP CONTROL SYSTEM
FOR DUMP VEX I CUE S
BACKGROUND OF THE INVENTION
This invention relates to a control system for the
dump body of a dump vehicle and pertains more
specifically to a novel electropneumatic dump control
system which affords, the finger pressure actuation of
the dump body.
A great variety of dump vehicles have been used
extensively, both on and off highways, as versatile and
efficient hauling units for loose materials. The dump
vehicle operator has heretofore encountered Defoe-
gullies, however, in controlling the up and down motion
of the dump body with respect to the vehicle chassis.
The typical conventional dump control system has been
purely pneumatic, including a control lever disposed on
one side of the operator's seat in the cab for the
actuation of a hoist cylinder control valve. The
operator has had to exert considerable force for
manipulating the control lever.
Further, installed close to the operator's seat,
the control lever and valve arrangement have occupied a
large proportion of the narrowly confined space within
the cab. It may be contemplated to mount the control
valve exteriorly of the cab. This solution is
unsatisfactory, however, as it requires as additional
linkage between the lever and valve.
The prior art pneumatic dump control system has
also made it difficult to provide electrical alarm means
such as pilot lamps indicative of the various working
conditions of the dump body The provision of such
alarm means is essential as the operation of the dump
vehicle demands utmost caution to minimize any hazard to
the workers.
US SUMMARY OF THE INVENTION
The present invention provides a novel dump control
system of mostly electrical (more specifically,
electropneumatic) construction which is capable of
finger pressure actuation, as by the depression of
~:Zg3~0
pushbutton switches, thus freeing the operator from the
physical labor heretofore required for operating the
dump body. By thus providing the electrified dump
control system the invention also solves the problem of
how to minimize the space it occupies within the cab.
Still further the invention makes possible the easy
provision of electrical alarm means for operating
safety.
The dump control system in accordance with the
invention comprises a hoist valve actuating mechanism
having fluid actuated cylinder means, and valve means
for the selective delivery of fluid under pressure to
the cylinder means. The valve means are operated
electrically by manual activation of switches.
An aspect of the invention is as follows:
A finger pressure actable dump control system for
a dump vehicle having a dump body, comprising:
a) a hoist valve actuating means for operating a
hoist valve comprising first and second fluid actuated
cylinders operatively connected to the hoist valve, the
first cylinder having an "up" chamber and a "float"
chamber, the second cylinder have a "down" chamber;
by a source of fluid under pressure;
(c) "up" valve means for on-off control of
communication between the "up" chamber of the first
cylinder and the pressurized fluid source;
(d) "float" valve means for on-off control of
communication between the "gloat" chamber of the first
cylinder and the pressurized fluid source;
(e) "down" valve means for on of control of
communication between the "down" chamber of the second
cylinder and the pressurized fluid source;
(f) "up" switch to be activated manually;
(g) a "hold" switch to be activated manually;
(h) a download switch to be activated
manually;
tip "up" circuit means for opening the "up" valve
means in response to the activation of the "up" switch;
pa ~L2~936~
(j) "hold" circuit means for closing the "up",
"float" and "down" valve means in response to the
activation of the "hold" switch:
(k) "down" circuit means for opening the "down"
valve means in response to the activation of the
"down/float" switch; and
(1) "float' circuit means for opening the float
valve means in response to the release of the
"down/float" switch.
The switches are preferably of the pushbutton type,
comprising an "up" switch for raising the dump body, a
"down/float" switch for lowering it, and a "hold" switch
for holding it stationary in any desired position. The
selective depression of these switches results in the
selective energization, or deenergization, of solenoid
valves which control the delivery of pressurized air to
the air cylinders of the hoist valve actuating
mechanism. The operator may simply activate the
pushbutton switches by light finger pressure, instead of
manipulating the heavy control lever as has been the
case heretofore, for controlling the dump body.
Perhaps as an incidental feature of the invention
the dump control system further comprises "up", "down",
"float" and
- - lZ;~9;~
1 "hold" pilot lamps to clearly indicate the operating conditions of
2 the vehicle. These pilot lamps glow in response to the actuation
3 of the switches.
4 The above and other features and advantages of this in-
mention and the manner of realizing them will become more apparent,
6 and the invention itself will best be understood, from a study of
7 the following description and appended claims, with reference had
8 to the attached drawings showing a preferred embodiment of the in-
9 mention.
11 BRIEF DESCRIPTION OF THE DRAWINGS
12
I FIG. l is a diagrammatic side elevation of the cab and
I neighboring parts of the dump vehicle incorporating the dump con-
trot system in accordance with the invention;
16 FIG. 2 is a diagrammatic top plan explanatory of the en-
17 rangement of the operator's seat, dump control console, etc., with-
18 in thy cab of FIG. 1, the dump control console having pushbutton
lug switches included in the dump control system in accordance with the
invention;
21 FOG. 3 is an enlarged side elevation, partly shown broken
away to reveal the inner details, of the dump control console of
23 ¦ FIG. 2;
I ¦ FIG. 4 is a top plan of the dump control console of FIG.
I i 3;
26 if FIX&. 5 is a rear elevation of the dump control console;
27 1¦ FIG. 6 is an elevation of the hoist valve actuating mock-
28 anise forming a part of the dump control system in accordance with
29 the invention;
¦ FIG. 7 is a schematic diagram showing the complete elect
11
l 3
3122~36~)
1 tropneumatic dump control system embodying the principles of this
2 invention;
3 FIG. 8 is a diagram similar to FIG. 7 but explanatory OX .
4 the operation of the dump control system when the dump body is be-
in raised;
6 FIG. 9 is also a diagram similar to FIG. 7 but explant
7 Tory of the operation of the dump control system when the dump
8 body reaches the topmost position;
9 FIX. lo is also a diagram similar to FIG. 7 but explant
N Tory of the operation of the dump control system when the dump
body is being initially lowered by the forced contraction of the
hoist cylinders;
13 FIG. if is also a diagram similar to FIG. 7 but explant
14 Tory of the operation of the dump control system when the dump
body is being lowered by gravity following the initial lowering by
16 the forced contraction of the hoist cylinders; and
I FIG. 12 is also a diagram similar to FIG. 7 but explant
18 Tory of the operation of the dump control system when the dump
lug ¦ body is being held against motion in any desired position interim-
dilate its raised and lowered positions.
21
DESCRIPTION OF THE PREFERRED EMBODIMENT
23
24 1 The reference numeral 20 in FIGS. 1 and 2 indicates the
25 scab of a standard dump truck. The cab 20 defines an operator come
26 apartment having a seat 22. Disposed on one side of the operator's
27 ¦ seat 22 and within easy reach of the operator sitting thereon is a
I I control console 24 for controlling the up and down motion of the
I dump body, not shown, of the vehicle in accordance with the novel
30 it concepts of the present invention. As illustrated on an enlarged
Al 4
5 ~293~i~
scale in FIGS. 3, 4 and 5, the control console 24 has
three pushbutton switches arranged in a row on its top
for activation by the vehicle operator. These switches
are:
1. An "up switch 26 for raising the dump body.
2. A "hold" switch 28 for holding the dump body
stationary in any desired angular position with respect
to the vehicle chassis.
3. A l'down/float" switch 30 for lowering the dump
body.
In FIG. 6 is shown a hoist valve actuating
mechanism 32, constituting a part of the dump control
system in accordance with the invention, for actuating
the hoist valve 11 controlling the hoist cylinders loan
lob for the dump body. Both hoist valve and hoist
cylinders fall outside the purview of the instant
invention. Suffice it to say that the hoist cylinders
for use with the representative dump control system
disclosed herein are telescopic. The telescopic hoist
cylinders are contracted, for lowering the dump body,
first by the forced circulation of the hydraulic fluid
and then under the weight of the dump body. The word
"float" used herein, as in the "down/float" switch 30,
indicates a condition allowing such lowering of the dump
body by gravity. The initial contraction of the hoist
cylinders by the forced circulation of the fluid is
necessary because the vehicle may stand inclined when
the dump body is in its topmost position; the body may
not turn in the proper direction without the forced
contraction of the hoist cylinders.
The hoist valve actuating mechanism 32 of FIG. 6
comprises first 34 and second 36 fluid actuated,
preferably pneumatic, cylinders. The first cylinder 34
has a piston rod 38 pin jointed at 40 to one end of a
lever 42. The second cylinder 36 has a drain port 36'
and a piston rod 44 slotted at 46 to slid ably receive a
pin 48 on the other end of the lever I This lever has
a rod or pin 50 midway between its opposite ends for the
actuation of the hoist valve 11. The pair of hoist
~2~:936~
cylinders loan lob are hydraulically connected through
the hoist valve 11 with a hydraulic fluid supply source
12. The hoist valve 11 includes a valve spool 13
pivotal connected to one end of a lever 14. The other
end of the lever 14 is fixedly connected to the pin 50.
The hoist cylinder lo and lob the hoist valve 11
including valve spool 13 and lever 14, and the hydraulic
fluid supply source 12 are conventional. The dump
control system in accordance with the invention effects
selective delivery of pressurized air into the air
chambers of the cylinders 34 and 36 in response to the
three pushbutton switches 26, 28 and 30 for controlling
the hoist cylinders, and therefore the dump body, via
the hoist valve.
FIG. 7 is a diagrammatic representation of the
complete dump control system, including the three
pushbutton switches 26, 28 and 30 on the top of the
control console by the side of the operator's seat and
the hoist valve actuating mechanism 32. The first
cylinder 34 has a rod end or "up" chamber 52
communicating with the outlet port 54 of an "up"
solenoid valve 56 by way of a conduit 58, and a head end
or "gloat" chamber 60 communicating with the outlet port
62 of a "float" solenoid valve 64 by way of a conduit
66. The second cylinder 36 has a rod end or "down"
chamber 68 communicating with the outlet port 70 of a
"down" solenoid valve 72 by way of a conduit 74. The
listed three solenoid valves 56, 64 and 72 have
respective drain ports (not shown) their inlet ports 76,
78 and 80 in constant communication with a source of
compressed air herein shown as in air reservoir 82 by
way of a conduit 84. The inlet ports 76 r 78, and 80 are
normally closed when valves 56, 64 and 72 are
deenergized.
Thus the energization of the "up" solenoid valve 56
results in the raising of the dump body. The
energization of the "down" solenoid valve 72 results in
the lowering of the dump body by the forced construction
of the telescopic hoist cylinders. The energization of
pa
12;~3
the "float" solenoid valve 64 results in the lowering of
the dump body by gravity. All the solenoid valves 56,
64 and 72 are deenergized for holding the dump body
against motion in a desired angular position and, at
that time, compressed air from reservoir 82 is
discharged through the drain ports of valves 56, 64 and
72. Thus, the hoist cylinders are operated by the
actual movements of cylinders 34 and 36~
The illustrated dump control system further
comprises the
12;~9360
1 following major components: .
2 1. First to fifth relays 86, 88, 90, 92 and 94 to cause
3 selective energization, and deenergization, of the solenoid valves
4 56, 64 and 72 in response to the pushbutton switches 26, 28 and 30.
2. Four pilot lamps 96, 98, 100 and 102 which are to glow
6 to indicate the "down", "up", "float" and "hold" conditions rest
7 pectively, of the dump body
8 3. A body switch 104 to be closed automatically when the
9 dump body reaches the topmost position -
4. An electric power supply 106 for energizing the sole-
11 nod valves 56, 64 and 72.
The first relay 86 has a movable contact 108, two fixed
13 contacts 1.10 and 112, a set circuit 114, and a reset circuit 116.
14 Tithe movable contact 108 engages the fixed contact 110 on energize-
¦ lion of the set circuit 114 and engages the other fixed contact 112
16 on energiza~ion of the reset circuit 116.. The second relay 88 is
I of like configuration, comprising a movable contact 118, two fixed
.8 contacts 120 and 122, a set circuit 124, and a reset circuit 126.
19 The movable contact 118 engages the fixed contact 120 on energize-
lion of the set circuit 124 and engages the other fixed contact 122
21 on energiæation of the reset circuit 126.
The first relay 86 has first 128 and second 130 terminals
I ¦ connected to the sex circuit 114, a third terminal 132 connected to
I 1 the fixed contact 110, a fourth terminal 134 connected to the move
25 if able contact 108, a fifth terminal 136 connected to the fixed con-
26 if tact 112, and sixth 138 and seventh 140 terminals connected to the
27 reset circuit 116. The first terminal 128 is further connected dip
I requital to the seventh terminal 140 via line 142. The second Fermi-
29 ! net 130 is further connected to the sixth terminal 130 via line 144
30 1 having a diode 146.
i
1, 7
~2936(j
1 The second relay 88 has first 148 and second 150 term-
2 nets connected to the set circuit 124, a third terminal 152 con-
3 netted to the fixed contact 120, a fourth terminal 154 connected to
4 the movable contact 118, a fifth terminal 156 connected to the fix-
Ed contact 122, and sixth 158 and seventh 160 terminals connected
6 to the reset circuit 126. The second terminal 150 of the second
7 relay 88 is connected to the seventh terminal 140 of the first no-
8 lay 86 via line 162 and further to the sixth terminal 158 of the
9 second relay via line 164. The fifth terminal 156 of the second
relay 88 is connected to the fourth terminal 134 of the first relay
11 86 via line 166.
The "up" switch 26 has a first fixed contact 168 con-
13 netted to a first fixed contact 170 of the "hold" switch 28 via .
14 i line 172, to the fourth terminal 154 of the second relay 88 via
I i line 174, and to a terminal A of a connector 176 via line 178. The
16 ¦ second fixed contact 180 of the "up" switch 26 is connected to the
17 sixth terminal 138 of the first relay 86 via line 182 and to the
18 seventh terminal 160 of the second relay 88 via line 184.
19 The first fixed contact 170 of the "hold" switch 28 is
connected to a fixed contact 186 of the "down/float" switch 30 via
21 line 188, besides being connected to the first fixed contact 168 of
I the "up" switch 26. A second fixed contact 190 of the "hold"
23 I switch 28 is connected to the first terminal 148 of the second no-
24 I lay 88 via line 192.
i The "down/float" switch 30 has another fixed contact 194
26 I connected to a terminal 196 of the fifth relay 94 via line 198, to
I a terminal 200 of the fourth relay 92 via line 202, and to the sea-
28 ¦ on terminal 130 of the first relay 86 via line 204.
29 I The third relay 90 has a terminal 206 connected to the
third terminal 152 of the second relay 88 via line 208, a terminal
,, 11 . I
- , 8
: ~2g3~
1 210 connected to the sixth terminal 158 of the second relay 88 via
2 line 212 and to a terminal 214 of the fourth relay 92 via line 216,
3 a terminal 218 connected to a terminal 223 of the fourth relay 92
4 via line 222~ and a terminal 224 connected to a terminal F of the
connector 176 via line 226.
6 The terminal 200 of the fourth relay 92 is grounded via
7 line 228 having a diode Z30j besides being connected to the fixed
8 terminal 194 of the "down/float" switch 30 via the line 202. The
9 terminal 214 of the fourth relay 92 is also grounded, besides being
connected to the terminal 210 of the third relay 90 via the line
11 216. Further the fourth relay 92 has a terminal 232 connected to
the terminal 132 of the first relay 86 via line 234, and a terminal
13 236 connected to the terminal B of the connector 176 via line ~38.
14 In addition to the terminal 196 connected to the fixed
contact 194 of the "down/float" switch 30, the fifth relay 94 has a
16 urinal 240 grounded, a terminal 242 connected to the terminal D
I of the connector 176 via line 244, and a terminal 246 connected to
18 the terminal 148 of the second relay 88 via line 248.
19 The terminal 136 of the first relay 86 is connected to
20 I the terminal C of the connector 176 via line 250. The terminal 1,2
21 of the second relay 88 is connected to the terminal E of the con-
nectar 176 via line 252
23 ! The connector 176 has the aforementioned sex of terminals
24 Al A, B, C, D, E and F and serves to electrically connect these term-
25 1! nets to another set of terminals A', B', C', D', E' and F', respect
I I lively. The terminal A' is connected to the power supply 106 via .
27 1¦ line 254 and also to a fixed contact 256 of the aforesaid body
28 ¦¦ switch 104 via line 258. The terminal B' is connected to the
29 I solenoid 260 of the "down" valve 72 via line 262 and to the term-
¦ net 264 of the "down" pilot lamp 96 via line 266. The terminal C'
Jo
I ~.~2~336~
1 is connected to the solenoid 268 of the "up" valve 56 via line 270
2 and to the terminal 272 of the "up" pilot lamp 98 via line 274.
3 The terminal D' is connected to a fixed contact 276 of the body
4 switch 104 via line 278. The terminal E' is connected to the ton-
final 280 of the "hold" pilot lamp 102 via line 282. The terminal
F' is connected to the solenoid 284 of the "float" valve 64 via
7 line 286 and to the terminal 288 of the "float" pilot lamp loo via
8 line 290.
OPERATION
Lo .'
I FIGS. 8 through 12 are explanatory of the operation of
18 the dump control system of FIG. 7, depicting its conditions in the
14 various aspects of dump body control. The following lines are used
I I in all these figures to clearly indicate the electrical functions
16 ¦¦ of the various connecting lines of the dump control system:
I 11 I Do and dash lines: Supply circuits from the power
I I supply 106. -
19 1 2. Dash lines: Grounding circuits.
20 j 3. Dotted lines: Relay energizing circuits.
21 ¦¦ 4. Thick lines: Supply circuits to the solenoid valves
¦¦ 56, 64 and 72 and to the pilot lamps 96, 98 7 100 and 102.
23 1¦ The "up" switch 26, "hold" switch 28, "down/float" switch
I Al 30, and body switch 1Q4 are all normally open as in FIG. 7.
I ,,
26 I' Raising the Dump Body
27 if
28 it The operator may depress the "up" switch 26, as in FIG.
29 Al 8, for raising the unsown dump body. The closed "up" switch 26
30 if connects the dot and dash line 178 from the power supply 106 both
, . ' ID
~2~g3~
1 to the dotted line 182 leading to the reset circuit 116 of the
2 first relay 86 and to the dotted line 184 leading to the reset air-
3 cult 126 of the second relay 88. Thus energized, the reset air-
4 cults 116 and 126 cause the movable contacts 108 and 118 to engage
the fixed contacts 112 and 122, respectively. It will be seen that
6 the supply line 178 is coupled directly to the dot and dash line
7 174 leading to the movable contact 118 of the second relay 88. The
8 relays 86 and 88 connect this line 174 to the terminal C of the
9 connector 176 via the thick lines 166 and 250. The corresponding
terminal C' of the connector is coupled to the solenoid 268 of the
if "up" valve 56 and to the "up" pilot lamp 98.
On energization the "up" solenoid valve 56 directs the
13 compressed air from the receiver 82 to the "up" chamber 52 of the
lo first cylinder 34 of the hoist valve actuating mechanism 32. The
lever 42 of this actuating mechanism actuates the hoist
16 control valve to cause extension of the unsown hoist cylinders.
lo Thus the dump body starts rising. The "up" pilot lamp 98 glows to
18 I indicate such rising of the dump body.
19 ¦ The operator may immediately release the "up" switch 26.
Since the movable contacts 108 and 118 of the first 86 and second
21 j 88 relays remain engaged with the fixed contacts 112 and 122, the
22 1 "up" solenoid valve 56 remains energized to cause the continued up-
23 1 ward motion of the dump body.
If With reference to FIG 9 the body switch 104 becomes
! automatically closed when the dump body reaches the topmost post
26 I lion. Being connected to the power supply 106 via the dot and dash
27 I lines 254 and 258, the closed body switch 104 causes the set air-
28 kowtow 124 of the second relay 88 to be energized via the dotted
29 Illness 278, 244 and 248. The movable contact 118 of the second no-
30 Al lay moves into engagement with the fixed contact 120 thereby con-
1., ,
If :
-- 36~
l netting the dot and dash line 174 to the thick line 252 leading to
2 the "hold" pilot lamp 102 via the terminals E and E' of the connect
3 ion 176 and the thick line 282. With all the solenoid valves 56,
4 64 and 72 thus deenergized, the hoist valve actuating mechanism
32 causes the dump body to become locked against motion in its
6 highest position. The "hold" pilot lamp 102 glows to indicate such
7 locking of the dump body in the raised position.
9 Lowering the Dump Body
I
if The operator may depress the "down/float" switch 30, as
in FIG. 10, for lowering the dump body. The power supply 106 is
13 constantly connected to the fixed contact 186 of the "down/float"
lo Switch 30 via the dot and dash lines 178, 172 and 188. Consequent-
, lye the closure of the "down/float" switch 30 results in the energy-
16 Ization of the relays 86, 92 and 94 via the dotted lines 204, 202
17 land 198. The energized set circuit 114 of the first relay 86
13 llcauses the movable contact 108 to move into engagement with the
lo 1Ifixed contact 110. The reset circuit 126 of the second relay 88 is
lasso energized via the dotted lines 182 and 184, causing the move
Al table contact 118 to engage the fixed contact 122. Thus the power
22 supply 106 becomes connected to the terminal B of the corrector 176
23 1! via the dot and dash lines 178 and 174 and the thick lines 166, 234
24 Al and 238. The associated terminal B' of the connector 1-76 is Jon-
25 netted to the solenoid 260 of the "down" valve 72 and to the "down"
26 pilot lamp 96.
27 Al On energization the "down" solenoid valve 72 directs the
28 comprised air into the "down" chamber 68 of the second cylinder 36
29 Al of the hoist valve actuating mechanism 32. The lever 42 becomes
positioned to initiate the descent of the dump body by the forced
12
3L2~:9360
-. .
1 contraction of the telescopic hoist cylinders. The "down" pilot
2 lamp 96 glows to indicate the descent of the dump body by the lore-
3 Ed contraction of the hoist cylinders.
4 As the operator subsequently releases the "down/float"
switch 30, all the relays become deenergized as in FIG. 11. The
6 movable contacts 108 and 118 of the first 86 and second 88 relays
7 remain engaged with the fixed contacts 110 and 122 respectively.
- 8 The result is the connection of the power supply 10~ to the term-
9 net F or the connector 176 via the dot and dash lines 178 and 174
and the thick lines 166, 234, 222 and 226. The associated terminal
11 F' of the connector 176 is connected to the solenoid 284 of the
"float" valve 64 and to the "float" pilot lamp 100.
13 The "float" solenoid valve 64 on energization delivers
14 the compressed air into the "float" chamber 60 of the first Solon-
15 ¦¦ per 34 of the hoist valve actuating mechanism 32. The lever 42 be-
16 ¦¦ comes positioned to allow the dump body to descend under its own
17 ¦¦ weight. The "float" pilot lamp 100 glows to indicate such gravity
18 ¦ fall of the dump body. The dump control system is in the state of
19 FIG. 11 even when the dump body is fully lowered.
2b
21 Holding the Dump Body
22
23 The "hold" switch 28 may be depressed as in FIG. 12 for
24 Holding the dump body against motion in any desired angular post-
25 jltion. The fixed contact 170 of this switch is in constant connect
26 It ion with the power supply 106 via the dot and dash lines 178 and
27 1! 172. Upon closure of the "hold" switch 28, therefore, the set air-
28 kowtow 124 of the second relay 88 becomes energized via the dotted
29 ¦ line 192, causing the movable contact 118 to engage the fixed con-
30 1 tact 120. The second relay 88 connects the dot and dash line 174
- I 13
9360
l to the thick line 252 leading to the terminal E of the connector
2 176. The associated terminal E' is connected only to the "hold"
3 pilot lamp 102.
4 As has been set forth in connection with FIG. 9, which
represents the condition where the dump body is in the topmost pox
6 session, the dump body becomes locked against motion upon deenergi-
ration of all the solenoid valves. The "hold" pilot lamp 102 glows
8 to indicate such locking of the dump body.
9 It is understood that the above disclosed embodiment is
lo by way of example only, since a variety of modifications will occur
to one skilled in the art to conform to the specific requirements
of the intended applications of the invention. Reference is there-
13 fore directed to the appended claims for the scope of protection to
14 be afforded to the invention.
16
17
18
19
I
I
23 1 .
25 ,
foe
it 1!
28 1
I 1
I I
