[0001] The present invention relates to a push-button controller for a crane and to a crane
control apparatus connected to it via a signal link.
[0002] Crane controllers are traditionally built as units fitted to suit a particular crane.
This means that the controllers for e.g. three cranes using identical machineries
but different control methods are each fitted individually to match the crane machineries.
Thus the control signals of a normal contactor-controlled crane are taken directly
from the crane controller's push buttons via a cable to the control apparatus of the
crane.
[0003] If a crane of the same type is equipped e.g. with a radio control system, the controller
is traditionally manufactured as a complete set with push buttons and radio transmitter
integrated in a common controller box.
[0004] If a crane of the same type is equipped with an infrared control system, the push
buttons and infrared transmitter are traditionally integrated with the box as single
unit.
[0005] Corresponding integration is also employed in the equipment used for the handling
of the signals in the crane itself. For example, the receiver for radio control is
integrated with the parallel interface from which the signals are taken in parallel
form to the crane drives.
[0006] A drawback in known technology is the difficulty of changing the control method.
Another notable drawback of known technology is the difficulty of achieving a uniform
appearance and image of the controller because the whole controller with all its equipment
is handled at the same time. Achieving a uniform appearance and image of the controller
is of course possible, but it is expensive.
[0007] The object of the present invention is to eliminate some of the drawbacks of previously
known technology and to achieve a crane control method that permits easier and cheaper
transition to a different control method, which can be utilized e.g. in the renovation
of cranes.
[0008] The invention is characterized by what is said in the characterization part of claim
1.
[0009] The invention has the following advantages. The push button unit is always the same
regardless of the control method, allowing a uniform appearance and image of the controllers
to be maintained irrespective of the control method.
[0010] The control method of a crane is easy to change when the circumstances change, e.g.
from cable control to wireless control.
[0011] Some parts of the push button controller, e.g. the push button unit 2, can be manufactured
in larger quantities, which means that e.g. the cost of the required plastic moulding
tools per controller is lower and therefore the whole push button controller becomes
cheaper.
[0012] The requirement of customers and the safety regulations of many countries that there
should be an alternate control method for radio control can be fulfilled more easily
than using controllers previously known in the art.
[0013] In the following, the invention is described in detail in the light of an embodiment
by referring to Fig. 1, which presents a modular push button controller system as
provided by the invention.
[0014] Fig. 1 shows a push button controller 1 connected via a signal link to the electric
system 26 of the crane and consisting of a push button unit 2 and at least one module
41, 42, 43, 44 which is in immediate contact with it and which transmits the control
signals to the electric system of the crane and, if necessary, also processes them.
The modules can be attached with a detachable joint 27 to the same push button unit
2. The detachable joint 27 connects the module and the push button controller together
without a large clearance and the joint can be secured with a self-locking mechanism.
Between the push button unit 2 and the module there is a detachable electric connection
9 for the control signals. A 'detachable electric connection' means an electric connection
permitting easy disconnection, preferably implemented as a plug-and-socket connector.
The detachable electric connectors of all modules 41...44 are compatible with the
corresponding connectors in the push button unit 2. The detachable joint 27 between
the modules 41...44 and the push button unit 2 can be provided with a sealing 28 to
protect it against environmental effects. The control buttons 3 of the push button
unit 2 are typically push buttons, control switches and signal lamps. Correspondingly,
the reception of control signals in the electric system of the crane is also implemented
using modules 18, 20, 21, 23 corresponding to the control method, and the modules
for different control methods can be easily changed in the electric system 26 of the
crane by normal operational measures.
[0015] Inserted into the push button unit 2 is a module 41 for a parallel communication
cable 5. The control signals 6 issued from the control buttons 3 are transmitted via
the detachable electric connection 9 to the module 41 and further through the cable
5 to the crane. In the crane the cable 5 is connected to a signal-transmitting cable
module 18 for parallel communication which transmits the control signals 6 via another
detachable electric connection 91 to the crane drives 25 in the control apparatus
26 of the crane. This second detachable electric connection is also preferably implemented
as a plug-and-socket connector and it can be protected with a sealing if necessary.
[0016] When the control method is to be changed into one based on serial communication,
a serial communication module 42 is connected to the push button unit 2. The serial
communication module consists of a first signal converter 8, in this case a parallel/serial
converter 8, and a serial communication cable 7. The control commands issued from
the control buttons 3 are transmitted via the detachable electric connection 9 to
the serial/parallel converter and further as a parallel signal 11 via a cable 10 to
a serial communication cable module 20 in the crane. From this module, the control
commands are transmitted to another signal converter 19 (serial/prallel converter)
and further via a second detachable electric connection 91 in serial form to the crane
drives 25 in the control apparatus 26.
[0017] When the control method is to be changed into radio control, a radio control module
43 is connected to the push button unit 2. The radio control module 43 consists of
a first signal converter 8 (parallel/serial converter) and a radio transmitter 12
with an aerial 13. The control commands issued from the control buttons 3 are transmitted
via the detachable electric connection 9 to the parallel/serial converter and further
in serial form to the radio transmitter module 12 and as a wireless signal from its
aerial 13 to a radio receiver 21 on the crane, via the receiving aerial 22. The control
commands are converted into parallel form by a second signal converter 19 (serial/parallel
communication module) and passed in parallel form via a second detachable electric
connection 91 to the crane drives 25 in the control apparatus 26 of the crane.
[0018] When the control method is changed to IR control (infrared transmitter/receiver),
the push button unit 2 is provided with an infrared-control module 44. The infrared-control
module 44 consists of a first signal converter 8 (parallel/ serial converter) and
an IR transmitter 15. The control commands issued from the control buttons 3 are transmitted
via the detachable electric connection 9 to the parallel/serial converter and further
in serial form to the IR transmitter 15. From here, the control commands are transmitted
as an IR signal 17 via a light source 16 to an IR receiver 23 on the crane, the receiver
being provided with one or more IR detectors 24. The control commands are then converted
into parallel form by a second signal converter 19 (serial/parallel communication
module) and passed in parallel form via a second detachable electric connection 91
to the crane drives 25 in the control apparatus 26 of the crane.
[0019] The signal converter 8 contained in modules 42...44 can also be constructed as a
separate module which is connected via a detachable electric connection, e.g. plug-and-socket
connectors, to the serial communication cable component 7, radio transmitter 12 or
IR transmitter 15 which transmits the signal to the crane. No parallel/serial converter
is needed for the parallel communication cable module 41 because the signals received
from the control buttons 3 are already in parallel form, but module 41 is still provided
with a detachable electric connection 9 (e.g. plug-and-socket connectors) compatible
with the detachable electric connection (plug-and-socket connectors) of modules 42...44.
[0020] The modules 41...44 and the push button unit 2 are preferably provided with a casing
of a totally enclosed type. The casing material is preferably plastic, the sealings
being advantageously flexible.
[0021] Items of equipment such as supporting ropes, holds and the like which may be needed
in the controllers are not presented because they are outside the scope of the invention.
[0022] A modular implementation as described above is also employed in the crane control
apparatus 26 in the crane itself. Push button controllers 1 with their modules 41...44
employing different control methods can be connected separately to the control apparatus
26 of the crane via compatible detachable connections. Similarly, the signal converters
19 can be connected to their receivers 20, 22, and 23 via a detachable electric connection
such as a plug-and-socket connection.
1. Push button controller (1) for a crane and a crane control apparatus (26) connected
to it via a signal link, characterized in that the push button controller (1) consists of a push button unit (2) and at
least one module (41, 42, 43, 44) attached to it with a detachable joint (27) and
transmitting or sending a control signal (6, 11, 14, 17) to the crane.
2. Push button controller (1) according to claim 1, characterized in that each one of the modules (41, 42 43, 44) transmitting or sending a control
signal can be separately attached to and detached from the same push button unit (2)
by means of a detachable joint (27).
3. Push button controller (1) according to claim 1 or 2, characterized in that the detachable joint (27) between the push button unit (2) and the module
(41, 42 43, 44) transmitting or sending a control signal is provided with a detachable
electric connection (9), preferably a plug-and-socket connection, and that any one
of said modules (41, 42 43, 44) transmitting or sending a control signal can be alternatively
connected to the push button unit (2).
4. Push button controller (1) according to claim 2 or 3, characterized in that the detachable joint (27) is provided with a sealing (28).
5. Push button controller (1) according to any one of claims 1...4, characterized in that the module (41, 42 43, 44) transmitting or sending a control signal sends
to the crane a parallel signal (6), a serial signal (11), a radio signal (14) or an
IR light signal (17).
6. Push button controller (1) according to any one of claims 1...5, characterized in that the module (41, 42 43, 44) transmitting or sending a control signal contains
a signal converter (8), such as a parallel/serial converter, between itself and the
push button unit (2).
7. Push button controller (1) according to claim 6, characterized in that the signal converter (8) is a separate unit between the push button unit
(2) and the module (42...44) transmitting or sending a control signal and that said
signal converter (8) is provided with a detachable electric connection (9) both on
the side of the push button unit (2) and on the side of the module (42...44) transmitting
or sending a control signal.
8. Crane control apparatus (26) receiving the control signal transmitted or sent by a
push button controller (1) according to any one of claims 1...7, characterized in that the control apparatus (26) comprises a module (18, 20, 21, 23) transmitting
or receiving the control signal (6, 11, 14, 17), said module being connected to the
control apparatus (26) of the crane either directly or via a signal converter (19).
9. Crane control apparatus (26) according to claim 8, characterized in that the connection between the module (18, 20, 21, 23) transmitting or receiving
the control signal and the crane control apparatus (26) is implemented using a second
detachable electric connection (91), e.g. a plug-and-socket connection, and that these
detachable electric connections (91) are of a uniform design such that any one of
said modules (18, 20, 21, 23) transmitting or receiving the control signal can be
alternatively connected to the second detachable electric connection (91) in the control
apparatus (26) of the crane.