Apparatus for the remote control of a transfer operation

The invention relates to apparatus for the remote control of transfer operations, in which a material to be transferred is taken from a supply tank into tanks to be filled, where a control signal with start and stop function is given by a hand station (1) to a control device at the delivery system for maintaining the transfer operation, while holding the filling valve open and in operation. The hand station (1) is equipped with a separate start and stop signal transmitter (14; 15) and a status indicator is also provided for assisting the operator.

BACKGROUND OF THE INVENTION 
1. Field of Invention 
The invention relates to apparatus for the remote control of transfer 
operations in which a material is transferred from a supply tank into a 
tank to be filled and more particularly for a device for the failsafe 
manual remote control of a valve and pump used in the filling operation. 
2. Description of the Prior Art 
In a known device for the remote control of tanking operations at airports, 
a manual device such as a hand rubber ball, button or lever switch, is 
connected by a hose or cable to the control device of the tanker and is 
maintained in an activated state by the operator as long as the filling 
operation is to continue. If the manual device is released, the control 
device closes the filling valve. Such a device is very inconvenient for 
the operator, as it can cause cramps in the operator's hand. In practice, 
the operator is not precluded from blocking the manual device. Thus, a 
hand rubber ball can be wedged and pressed down under a wheel of the 
tanker thereby defeating its safety function. However, in certain 
instances, such as refueling of aircraft remote manual control is 
absolutely essential because it is not assured in practice that the amount 
of fuel to be taken on as requested the flight personnel is accurate or is 
consistent with the capacity of the tank. Incorrect setting of the desired 
amounts at the control device is another source of error. Furthermore, the 
tanker hose can also become defective or other problems can occur. 
Similar problems occur generally in the transfer of dangerous liquids or 
other materials such powders or granular materials. The danger may be due 
to flammability, poisonous nature or the like of these materials. It may 
also involve expensive material which must not be spilled or generally 
operations executed by robots which are to be controlled effectively by 
hand. 
SUMMARY OF THE INVENTION 
It is an object of the invention to develop apparatus for the remote 
control of transfer operations which is substantially safer than the 
devices commercially available and which is more comfortable for the 
operator. 
According to this invention, a hand station for controlling fluid flow into 
a tank is equipped with a separate start and stop signal transmitter which 
interacts with the control device at the carrier of the supply tank in the 
following manner: 
After the control device is turned on, a state indicator is switched to 
"ready". After a start signal is actuated, the control device deactivates 
the state indicator, and the filling valve is opened for the pumping 
operation. After a first time interval, the state indicator is activated 
again. Until the end of a second time interval, the filling valve is kept 
open, the pump remains turned on and the filling operation can be 
reactivated by the start signal. Without actuation of the start signal, 
however, the filling valve is closed and the pump is shut down, or brought 
to a reduced output, for instance by reducing its speed. The filling valve 
can be closed and the pump turned off or its output reduced at any time by 
activating a stop signal. 
Thereby, safety functions as well as control measures of the transfer 
operation are possible from the hand station without adverse mutual 
interaction. 
The safety function is met in principle by a so-called dead man's circuit. 
A similar dead man's circuit is known as a safety travel circuit for the 
wireless remote control of locomotives in such a manner (German Pat. No. 
24 50 074) that an emergency stop is initiated if in a first time 
interval, an acoustic-optical signal transmitter has been put in operation 
and during a subsequent second time interval, a control command for 
changing the state of motion of a locomotive is not given. Although such a 
safety travel circuit as well as the simpler dead man's circuit at the 
control station of locomotives have been known for a long time, their use 
for securing tanking operations has not been considered to date. In 
practice and in the literature, in particular, references are lacking as 
to how known dead man's circuits could be adapted to tanking operations. 
In practice, it is advisable to arrange the control advice at the delivery 
system, for instance, at a tank vehicle in such a manner that upon receipt 
of the stop signal, not only is the filling valve closed and the pump is 
shut down or its output reduced but at the same time the state indicator 
is activated. 
According to a further embodiment, the hand station is equipped with an 
infrared transmitter with a start and stop signal transmitter and the 
control device has an infrared receiver which can be tuned to the infrared 
transmitter. By using infrared light as the transmission medium, 
interference by electromagnetic field and/or by acoustical interference 
waves is eliminated. 
The hand station can be equipped with an infrared transmitter with a start 
and a stop signal transmitter and with a coding device, where the control 
device comprises an infrared receiver which can be turned to the infrared 
transmitter by a single-command decoder as a security measure. Such coding 
devices are absent in the known safety circuits. 
A suitable circuit for the control device consists of the infrared receiver 
with an amplifier and is followed by a decoder, the output of which is 
connected via single-command decoder, first, to a decimal decoder as part 
of a counting device which obtains its timing by a clock generator, and 
second, directly to a time-setting device of the counting device. The 
time-setting device sets the duration of the first and second time 
intervals. The output of the time setting device for the first time 
interval is connected to the state indicator and the output of the time 
setting device for the second time interval with the addressing device for 
the filling valve. The filling valve may be controlled directly or through 
an intermediate control valve.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The apparatus for the remote control of the transfer operations according 
to FIG. 1 comprises a hand station and a control device which selectively 
activates state indicator (i.e., a lamp) 11 and a control valve 12. The 
hand station 1 may be realized as an infrared transmitter with a coding 
device, in which case the control device may comprise a receiver 2, 
including an infrared receiver with a pre-amplifier. The control device 
further consists substantially of a decoder, 3, a single-command decoder 
4, a counting device 13 as well as of power stages 9, 9' for the state 
indicator 11, and the control valve 12. The individual subassemblies of 
the control device are connected to a voltage supply 10. The hand station 
1 has a start signal transmitter 14 and a stop signal transmitter 15. 
A tank or storage container holds the material to be dispensed. The 
contents of tank 30 are pumped out by pump 28 through a filling valve 27. 
The filling valve is operated by a control valve 12 by using either 
hydraulic or pneumatic control signals, through pipe 31. In addition, if 
desired, pump 28 may be selectively operated by means of a control signal 
on line 32 from stage 9. 
The decoder 3 consists of an integrated circuit 16 for the infrared signal 
evaluation, for instance, a SAB 3209, monostable multivibrators 17 and 18, 
a shift register 19 and a command group decoder 20. The counting device 13 
consists substantially of a clock generator 5 such as an oscillator; a 
decimal decoder 6, a time setting device 7 for the first time interval t1 
and a time setting device 8 for the second time interval t2. 
The apparatus operates as can be seen from the following function table for 
each action at the hand station 1 or at the control device at the delivery 
system: 
______________________________________ 
LAMP 
ACTION (State indicator 11) 
FILLING VALVE 27 
______________________________________ 
1 Off Closed 
2 On Closed 
3 Off Open 
4 Off Open 
5 Off Open 
6 Off/ Open/ 
after t1: after t2 
On Closed 
7 On Closed 
8 On Closed 
______________________________________ 
If the control device is switched off (action 1), the state indicator 11 is 
turned off and the filling valve 27 is closed. If the control device at 
the delivery system is switched on (action 2), the state signal 
transmitter is switched on and the filling valve remains closed. If the 
start signal transmitter 14 of the hand station 1 is then actuated (action 
3), the state signal transmitter 11 is switched off and the filling valve 
27 is opened. If the start signal transmitter 1 is actuated again within 
the first time interval t1 (action 4), the state indicator 11 remains 
switched off and the filling valve remains open. If the start signal 
transmitter is operated within the second time interval after the state 
signal transmitter had been switched on (action 5), the state signal 
transmitter is switched off again and the filling valve remains open. 
If the start signal transmitter is operated at the beginning of the 
transfer operation and is not operated again during period t1 (action 6), 
the state indicator (which is initially switched off) is switched on at 
the end of the first time interval t1. The filling valve is open over the 
first time interval t1 and it is closed at the end of the second time 
interval t2. If the start signal transmitter 14 is not operated at the 
beginning of a filling operation, the state indicator remains switched on 
and the filling valve remains closed (action 7). Any time the stop signal 
transmitter 15 of the hand station 1 is actuated, the state indicator 11 
is switched on and the filling valve is closed (action 8). 
By example, for refuelling an aircraft, the supply requested fuel quantity 
filled is first set at an overfill protection device (not shown). The 
control device at the delivery system is then switched on and pumping of 
fuel begins by activating the start signal transmitter 14 at the hand 
station 1. The different operating states have been explained with the aid 
of the table. The tanking operation is terminated if the hand station 
delivers a stop signal, by not operating the start signal transmitter or 
if the set quantity was delivered. In addition, the device can be adapted 
in a manner known per se to the situation in which a given pressure change 
in the pumping line, customarily in the event of a pressure increase, the 
control device of the filling valve closes automatically with a so-called 
fast stop. 
If the start signal transmitter 14 is actuated at the hand station 1, the 
infrared transmitter sends an address consisting of a start signal, 
encoded information and closing command. A similar but different address 
is sent if the stop signal transmitter 15 is actuated. The infrared 
receiver 2 converts the address received as light signals into electrical 
signals and amplifies it in the pre-amplifier. In the first decoder 3, the 
integrated circuit for the signal evaluation 16, SAB 3209 contains 
substantially a Schmitt trigger oscillator with an externally connected 
tuned LC circuit (not shown) for generating the internal clock frequency. 
In this module the signals already processed by the pre-amplifier are 
amplified again and are fed at the original frequency to an the internal 
series interface. More particularly the information signals are fed to the 
shift register 19 via the data line 21. A start signal likewise is fed to 
the shift register 19 via the line 22 and a monostable multivibrator 17 
from the comparator output of the Integrated circuit for evaluating the 
infrared signal, 16. A line 23 also feeds a trigger signal to the 
monostable multivibrators 17 and 18. In the command group decoder 20, a 
preset coded signal is compared with the one received from the shift 
register. In the case of signal agreement in the group, the single-command 
decoder 4 can effect the single signal comparison. In the case of 
agreement of both the group and individual signals, counter device 13 is 
enabled through single-command decoder 4. 
In FIGS. 2A and 2B, details of an embodiment example are shown. Three 
infrared receivers with pre-amplifiers 2a, 2b and 2c can be connected to 
the decoder 3. Therefore, the receivers can be arranged at the delivery 
system, for instance, a tank vehicle, at three different points in order 
to make sure that the control device can receive commands by the hand 
transmitter from different positions. At the coding switches S1 to S4 of 
the command group decoder 20, programming can be carried out for two 
channels of the receiver (signal from the start signal transmitter and 
signal from the stop signal transmitter) upon a command of 15 command 
groups of two commands each and encoded thereby. The receiver decodes from 
the serial data sequence of the signal furnished by the preamplifier, the 
corresponding command and controls the output of the associated channel. 
Thereupon, the output of the command group decoder 20 is kept open and 
connected through via a driver gate 24 approximately for the duration of 
the actuation of the start signal transmitter at the hand transmitter 1. 
In the clock generator 5, a base time of 5, 10 or 15 seconds can be set by 
inserting programmable jumpers A1, A2, A3. The decimal decoder 6 controls 
the warning and shut-off time for the state indicator 11 and for the 
control valve 12. in the time setting device 7, jumpers X1 to X7 can be 
inserted, whereby a multiple of the base time can be set as the first time 
interval t1. At the time-setting device 8, jumpers Y1 to Y7 can be 
inserted, for instance, as programming plugs, whereby a multiple of the 
base time can be set as a second time interval t2. 
In the embodiment example, a voltage supply for +12 V to reference 
potential is used as the on-board network for each of the modules. The 
voltage supply 10 is stabilized in a manner known per se. 
In the embodiment example the following standardized integrated circuits 
are used: 
For the monostable multivibrator 17 and the monostable multivibrator 18, an 
MC 14538 BCP; for the shift register 19, and 14015 BCP; for the clock 
generator 5, an IC 25, namely, a 14541; for the decimal decoder 6, a 
14027; for the time setter 7 and 8 jointly an MIC 26, namely a 14017; and 
ahead of the output of the time setting for the first time interval, 7, a 
14027. In the power stages 9, a Darlington transistor each can be used. 
Otherwise, gates, resistors and capacitors and further components are used 
in the manner shown.