Communications: electrical – Condition responsive indicating system – Specific condition
Reexamination Certificate
2002-04-18
2004-08-24
La, Anh V. (Department: 2636)
Communications: electrical
Condition responsive indicating system
Specific condition
C340S679000, C340S521000, C340S525000, C070S017000, C014S069500
Reexamination Certificate
active
06781516
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to control panels for loading dock equipment. More particularly, the present invention relates to a simplified and unified control panel for operating loading dock equipment.
BACKGROUND OF THE INVENTION
This invention is a master control panel which simplifies the operation of loading dock equipment. In addition to having a dock leveler and overhead door, a loading dock may also have a vehicle restraint, loading light, barrier gate and inflatable shelter. If the various devices are power operated rather than manually operated, the wall beside the doorway may be cluttered with various control panels. Not only is the space between doors often very restricted, but the cost of the electrical installation can be significant. This situation can be improved with the installation of a combination control panel which includes all of the controls in a single enclosure. The combination panel not only saves space but may also reduce the cost of electrical installation. One criticism of existing combination panels has been that the operator may be confused by the various number of switches and push buttons, and the proper sequence of operation.
DESCRIPTION OF RELATED ART
FIG. 1
illustrates a loading dock with a driveway
1
, dock wall
2
, dock floor
3
. A pit
4
is recessed in the floor
3
. A dock leveler assembly
10
has a deck assembly
11
, and a frame assembly
12
which is mounted in the pit
4
. Lip keepers
14
are mounted to the front of the frame. The rear of a deck assembly
11
pivots on the frame assembly
12
and has a lip hinge
13
at the front. A lip assembly
15
is supported at one end by the lip hinge
13
and has the other end resting on the lip keepers
14
.
The doorway of the loading dock can be closed by a movable door
18
, shown partially open. A vehicle restraint assembly
20
is mounted to the wall
2
and has a hook
21
, which moves vertically to engage the ICC bar of a truck or tractor trailer (not shown). A light assembly
23
is mounted beside the doorway and has a red light
24
and a green light
25
to signal the truck driver. Two signs
26
and
27
instruct the driver to move only when the green light is illuminated. The sign
26
has reversed lettering to be legible when viewed in the truck mirror. A loading light
28
is mounted beside the doorway to illuminate the interior of the trailer during loading. A barrier gate assembly
30
has a barrier arm
31
which moves from a horizontal position where it prevents access to the doorway to a vertical position where it allows access to the doorway.
An inflatable shelter assembly
35
has two side bags
36
and a head bag
37
which are inflated by a motor and blower (not shown). When a truck or trailer is at the dock, the bags inflate to form a seal between the truck or trailer and the dock wall.
FIG. 2
demonstrates a typical loading dock area with control panels for a hydraulic dock leveler, electric vehicle restraint and power operated door. The dock leveler control panel
40
has three buttons, button
41
raises the dock leveler deck assembly
11
, button
42
extends the hinged lip plate
15
, and button
43
is an Emergency Stop which stops all of the dock leveler functions. The vehicle restraint control panel
50
has a selector switch
51
, an engage button
52
and a release button
53
. Three lights
55
,
56
and
57
which are red, amber and green respectively, indicate to the dock operator the status of the vehicle restraint. The selector switch
51
has three positions, Off, On, and Lights Only, which allows the operator to bypass the vehicle restraint if the truck or trailer cannot be captured by the vehicle restraint and must be restrained by wheel chocks. The door control panel
60
has three buttons, an Open button
61
, a Close button
63
and a Stop button
62
.
The normal operating sequence of the equipment is as follows:
When the dock is not in use, the exterior green light
25
is illuminated to indicate that the truck driver may approach or leave the dock. The interior red light
55
is illuminated to indicate that the dock is not in a condition for use. The operator selects the vehicle restraint control panel
50
and presses the engage button
52
. The vehicle restraint hook
21
, of
FIG. 1
, rises to engage the truck or trailer. When the hook
21
starts to rise, the exterior red light
24
is illuminated to indicate that the truck driver cannot leave. When the truck or trailer has been effectively restrained, the interior green light
57
is illuminated to indicate that the dock is ready to use. If the vehicle restraint
20
cannot restrain the trailer, the dock operator must manually chock the truck or trailer wheels. The operator may then turn the selector switch
51
from On to Lights Only. Both the interior green light
55
and amber light
56
are now illuminated to indicate that the dock is safe to use, but that the operator should use greater caution because the vehicle restraint
20
has not engaged the truck or trailer.
The operator selects the door control panel
60
and presses the Door Open button
61
to open the door
18
.
The operator selects the dock leveler control panel
40
and presses the Raise button
41
to raise the deck assembly
11
, extend the lip assembly
15
, and releases the button to lower the leveler onto the trailer. Pressing the Lip Extend button
42
allows faster operation by causing the lip
15
to extend before the deck assembly
11
is fully raised. Pressing the Emergency Stop button
43
causes the dock leveler to stop so that it will not descend on top of any misplaced cargo.
If a loading light
28
is installed it may have a manual switch or may be automatically turned on when the door is opened. Similarly, an inflatable shelter
35
may be operated by a manual switch or be automatically turned on when the door is opened.
When the loading operation is finished, the operating sequence is reversed.
The operator presses the dock leveler Raise button
41
to raise the deck assembly
11
, fold the lip assembly
15
and then releases the button to lower the dock leveler to the stored position.
The operator presses the Door Close button
63
to close the door
18
. Pressing the Stop button
62
causes the door to stop before it closes.
The operator presses the Release button
53
and the vehicle restraint hook
21
lowers to release the trailer. When the hook
21
starts to lower, the interior red light
55
is illuminated to indicate that the dock is not ready for use. When the hook is fully lowered, the exterior green light
25
is illuminated to indicate that the truck driver may leave.
FIG. 3
demonstrates a typical combination control panel with controls for a hydraulic dock leveler, electric vehicle restraint and power operated door. The control buttons and switches have the identical functions of the separate panels in FIG.
2
. Often, a Programmable Logic Controller (PLC) is used to allow many different control sequences and interconnect relationships. A PLC accepts input signals from various devices such as limit switches and push buttons and then transmits output signals to various devices such as lights, relays and motors in accordance with the logic defined by the control program. The use of a PLC is well known in the loading dock industry and the specific electrical circuits and program statements are not shown nor discussed herein.
Although the control buttons and switches are arranged in functional groups and are clearly labeled, an untrained operator may find that the number of buttons and their differing locations make the proper sequence of operations seem confusing. Therefore, this invention provides a combination panel with all of the advantages of compact space and economical installation, and with a simplified operating sequence.
Accordingly, it is desirable to provide a simplified combination panel for controlling loading dock equipment and a method for operating loading dock equipment with a simplified control panel.
SUMMARY OF THE INVENTION
It is th
Alexander James C.
Reynard Terence
Baker & Hostetler LLP
La Anh V.
United Dominion Industries, Inc.
LandOfFree
Master control panel for loading dock equipment does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Master control panel for loading dock equipment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Master control panel for loading dock equipment will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3321470