Warming-up type bill validator

A temperature sensor 51 is provided in the bill validator according to the present invention to produce a detection signal when a temperature in the case 11 is lowered below a predetermined level. Upon occurrence of the detection signal of the temperature sensor 51, a first timer starts counting a confirmative period of time. When the first timer counts up the confirmative period of time, a second timer produces a drive signal to activate the conveyer motor 38 for a predetermined warming-up period of time. As the conveyer motor 38 is rotated for warming-up, the belt 23 runs in the case 11 to revive its flexibility and generate heat due to dynamic friction of the mechanic parts including the conveyer motor 38, pulleys 21, 22 and belt 23 during rotation of the conveyer motor 38.

FIELD OF THE INVENTION 
This invention relates to a bill validator, in particular a warming-up type 
bill validator capable of preventing breakdown or failure of the bill 
validator resulted from cold air. 
PRIOR ART 
Bill validators have been used in vending machines, money exchangers, bill 
dispensers or other kind of many bill handling machines all over the 
countries. A typical bill validator comprises a case having an inlet into 
which a bill is inserted and an outlet from which the bill is discharged; 
an inlet sensor for detecting insertion of the bill into the inlet; a 
conveyer device for transporting the bill from the inlet to the outlet 
through a passageway in the case; a bill sensor disposed adjacent to the 
passageway for converting into electric signals optical or magnetic 
feature of the bill; and a validating control circuit electrically 
connected with the inlet sensor, conveyer device and bill sensor for 
driving the conveyer device. When the bill is inserted into the inlet, the 
inlet sensor products a detection signal to the validating control circuit 
which starts rotation of a motor of the conveyer device. Therefore, the 
bill is transported from the inlet toward the outlet by a flexible 
conveyer belt along the passageway so that the bill sensor converts into 
electric signals optical or magnetic feature of the bill moving through 
the passageway. The conveyer belt is wound around and moved by pulleys 
rotated by the motor. The validating control circuit compares output 
signals from the bill sensor with an optical or magnetic pattern 
previously stored in the validating control circuit. If the output signals 
from the bill sensor are correspondent to the stored pattern, the 
validating control circuit forwards a drive signal to the conveyer device 
to transport the bill to the outlet so that the bill is sent to a stacker 
for accumulation after discharged from the outlet. Adversely, if the 
output signals from the bill sensor are not correspondent to the stored 
pattern, the validating control circuit forwards a different drive signal 
to the conveyer device to return the bill to the inlet. 
In some cases, bill validators are broken down in cold districts because 
the conveyer belt is hardened under the low atmospheric temperature so 
that the belt cannot return to its flexible property for smooth rotation 
when the conveyer device is suddenly driven after it is paused in cold 
atmosphere for a long time. In particular, a congealed curved portion of 
the belt wound around the pulley cannot be deformed into its straight 
shape for rotation, thereby causing breakdown or failure of the conveyer 
device. In addition, below the freezing point of atmospheric temperature, 
ice is deposited on parts within the bill validator, and it may result in 
trouble of the bill validator. 
An object of the present invention is to provide a bill validator that can 
prevent breakdown or failure thereof resulted from cold air by performing 
appropriate warming-up operation. 
Another object of the invention is to provide a bill validator which can be 
well operated in a cold atmosphere without a heater. 
A still another object of the invention is to provide a bill validator 
whose inside can always be kept in good condition for smooth operation at 
low atmospheric temperature. 
SUMMARY OF THE INVENTION 
The bill validator according to the present invention comprises a case 
having an inlet into which a bill is inserted and an outlet from which the 
bill is discharged; an inlet sensor for detecting insertion of the bill 
into the inlet; a conveyer device for transporting the bill from the inlet 
to the outlet through a passageway in the case; a bill sensor disposed 
adjacent to the passageway for converting into electric signals optical or 
magnetic feature of the bill moving through the passageway; and a 
validating control circuit electrically connected with the inlet sensor, 
conveyer device and bill sensor for driving the conveyer device. The 
conveyer device has a belt for transporting the bill along the passageway 
and a conveyer motor drivingly connected with the belt. The bill validator 
further comprises a temperature sensor for producing a detection signal 
when a temperature in the case is lowered below a predetermined level; a 
first timer for starting counting a confirmative period of time upon 
receiving the detection signal from the temperature sensor, and a second 
timer for producing a drive signal when the first timer counts up the 
confirmative period of time to drive the conveyer motor for a 
predetermined warming-up period of time. 
When the temperature in the case is lowered below the predetermined level, 
the temperature sensor produces a detection signal which lets the first 
timer start counting a confirmative period of time. When counts up the 
confirmative period of time, the first timer produces an output by which 
the second timer produces a drive signal to activate the conveyer motor 
for a predetermined warming-up period of time. As the conveyer motor is 
rotated for run-in or warming-up, the belt runs in the case to revive its 
flexibility and generate heat due to dynamic friction of the mechanic 
parts including the conveyer motor, pulleys and belt during rotation of 
the conveyer motor. Thus, the warming-up operation can prevent hardening 
of the belt and elevate the interior temperature of the case to an 
appropriate level without a heater. 
In an embodiment of the present invention, the conveyer motor may be 
rotated in the reverse direction by the drive signal of the second timer. 
The temperature sensor comprises an electrical sensor of a thermostat or a 
temperature-sensitive capacitor or a mechanical sensor of a bimetal or a 
shape memory alloy. The operation of the conveyer motor can be stopped 
when the temperature sensor decides that the interior of the case is 
warmed to a predetermined temperature during the warming-up period of time 
.

DETAILED DESCRIPTION OF THE INVENTION 
An embodiment of the present invention will be described hereinafter 
referring to FIGS. 1 to 3. 
A bill validator 10 of this invention comprises a case 11 having an inlet 
13 into which a bill is inserted and an outlet 14 from which the bill is 
discharged; an inlet sensor 40 provided adjacent to the inlet 13 for 
detecting insertion of the bill into the inlet 13; a conveyer device 15 
for transporting the bill from the inlet 13 to the outlet 14 through a 
passageway 12 in the case 11; a bill sensor 16 disposed adjacent to the 
passageway 12 for converting into electric signals optical or magnetic 
feature of the bill moving through the passageway 12. The bill validator 
10 forms a validating unit 20 removably attached to a transport apparatus 
24. 
The bill sensor 16 comprises infrared ray optical sensor 41 for picking up 
optical features of the bill and a magnetic sensor 42 for detecting 
magnetic features of the bill. An outlet sensor 45 is provided adjacent to 
the outlet 14 of the passageway 12 to detect discharge of the bill. The 
conveying device 15 comprises a pair of pulleys 21, 22; and a belt 23 
wound around the pulleys 21, 22. The pulley 22 is operatively connected to 
a conveyer motor 38 to drive the belt 23 so that a bill is transported by 
the belt 23 from the slot 13 to the outlet 14. Not shown but a rotary 
encoder is attached to the conveyer motor 38 to detect rotation of the 
conveyer motor 38. The passageway 12 formed by the conveying device 15 is 
aligned with a carrier passage 26 formed in a transport apparatus 24 which 
comprises pulleys 27, 28, 29, 30 and 31 provided adjacent to the carrier 
passage 26, and a belt 32 wound around the transporting pulleys 27 to 31 
so that the bill discharged from the outlet 14 of the bill validator 10 is 
continuously carried by the transport apparatus 24. The pulleys 27, 28 and 
29 are rotatably mounted so that their upper surfaces are positioned 
nearly on a same plane toward push rollers 39, 33 and the pulley 31. A 
transport motor 34 has an output shaft to which a pinion 35 is mounted in 
engagement with an intermediate gear 36. An output gear 37 is meshed with 
the intermediate gear 36 for rotation together with the drive pulley 30 
disposed outside an upwardly bent area 26a of the carrier passage 26 to 
smoothly drive the belt 32 along the bent area 26a of the carrier passage 
26 to travel the bill through the bent area 26a and exit 26b into a 
stacker 25. A printed circuit board 50 is disposed in the transport 
apparatus 24 to support a temperature sensor 51 which produces a detection 
signal when an interior temperature of the case 11 is lowered below a 
predetermined level, for example zero degree. To this end, the temperature 
sensor 50 may be selected from an electrical sensor of a thermostat or a 
temperature-sensitive capacitor or a mechanical sensor of a bimetal or a 
shape memory alloy. 
As shown in FIG. 2, the inlet sensor 40, infrared ray optical sensor 41, 
magnetic sensor 42, outlet sensor 45 and temperature sensor 51 are 
electrically connected with each corresponding input terminal of a 
validating control circuit 80. The rotary encoder attached to the conveyer 
motor 38 is also electrically connected with the control circuit 80 which 
counts the pulses from the rotary encoder to detect rotation of the 
conveyer motor 38. Each output terminal of the validating control circuit 
80 is connected with the transport motor 34 and conveyer motor 38. Not 
shown but, the validating control circuit 80 comprises first and second 
timers formed by programmed control in the validating control circuit 80. 
Upon receiving the detection signal from the temperature sensor 51, the 
first timer starts counting a confirmative period of time for example 
fifteen minutes and produces an output when counts up the confirmative 
period of time. When the first timer counts up the confirmative period of 
time or generates the output, the second timer produces a drive signal to 
activate the conveyer motor 38 for a predetermined warming-up period of 
time for example five seconds. 
The bill validator of the present invention is worked in accordance with an 
operational sequence shown in flow chart of FIG. 3. 
The processing moves from "START" of Step 100 to Step 101 wherein the 
validating control circuit 80 judges by the output of the inlet sensor 40 
whether a bill is inserted or not. If this is negative, the treatment goes 
to Step 102 wherein the validating control circuit 80 decides by the 
output of the temperature sensor 51 whether the temperature in the case 11 
is lowered below a predetermined level by cold atmosphere. In this case, 
if the temperature in the case 11 is lowered below the predetermined 
level, the temperature sensor 51 produces a detection signal to the first 
timer which thereby starts counting a confirmative period of time (Step 
103). In Step 104, the control circuit 80 make a decision whether the 
first timer counts up the confirmative period of time to confirm that the 
inside of the case 11 is continuously below the predetermined low 
temperature for the certain period of time. When the first timer counts up 
the confirmative period of time in Step 104, it produces an output and 
then is reset (Step 105). Thereafter, the processing advances to Step 106 
wherein the validating control circuit 80 determines whether the inlet 
sensor 40 is turned "ON" or not by inserting a bill into the inlet 13. 
When the inlet sensor 40 is in the "OFF" condition in Step 106, in 
accordance with generation of the output from the first timer, the second 
timer produces a drive signal in Step 107 so that the conveyer motor 38 is 
rotated in the reverse direction for a given warming-up period of time in 
Step 108 by the drive signal of the second timer. As the conveyer motor 38 
is rotated for warming-up, the belt 23 runs in the case 11 to revive 
flexibility of the belt 23 and generate heat due to dynamic friction of 
the mechanic parts including the conveyer motor 38, pulleys 21, 22 and 
belt 23 during rotation of the conveyer motor 38. Thus, the warming-up 
operation can prevent hardening of the belt 23 and elevate the interior 
temperature of the case 11 to an appropriate level without a heater. In 
Step 109, the control circuit 80 decides whether the second timer counts 
up the predetermined warming-up period of time. When the period of time is 
over in Step 109, operation of the conveyer motor 38 is stopped in Step 
110 and the processing returns to Step 101. When the temperature in the 
case 11 is not lowered below a predetermined level in Step 102 or when the 
first timer does not count up the confirmative period of time in Step 104, 
the stage is returned to Step 101. When the second timer does not count up 
the given warming-up period of time in Step 109, the process returns to 
Step 108. 
When the inlet sensor 40 is turned "ON" in Step 101 or 106, the control 
circuit 80 supplies drive signals to the conveyer motor 38 which therefore 
is rotated in the forward direction to transport the bill along the 
passageway 12. The bill sensor 16 detects optical or magnetic features of 
the bill moving along the passageway 12 so that the control circuit 80 
judges from the output of the bill sensor 16 in Step 112 whether the bill 
is genuine or not. If this is affirmative, the bill is moved to a stacked 
position (Step 113). Then, the conveyer motor 34 is rotated in the reverse 
direction (Step 114) for stacking operation of the bill into the stacker 
25. The control circuit 80 determines whether it counts up a predetermined 
number of pulses from the rotary encoder connected with the conveyer motor 
38 in Step 115 to confirm completion of the stacking operation. When the 
control circuit 80 counts up the predetermined number of pulses, the 
process goes to Step 110. When the bill is considered not genuine in Step 
112, the control circuit 80 drives the conveyer motor 38 in the adverse 
direction in Step 116, and when it concludes that the inlet sensor 40 is 
turned "OFF" in Step 117, the processing goes to Step 110. 
The embodiment of this invention is not limited to the foregoing example 
and modifications can be made in the embodiment. For example, the 
transport motor 34 as well as the conveyer motor 38 may simultaneously be 
driven for warming-up when no bill is inserted. However, usually 
warming-up operation of only the conveyer motor 38 for the given period of 
time is enough to prevent breakdown of the bill validator 10 under low 
temperature because the conveyer motor 38 is very close to the inlet 13 
through which cold air enters the validator 10. 
The confirmative period of time may vary for example from 20 seconds to an 
hour, and the warming-up period of time may vary for example from three 
seconds to fifteen minutes as required. The temperature sensor 51 can 
detect a temperature ranging between for example zero to five degrees. The 
validating control circuit 80 can be so designed that the operation of the 
conveyer motor 38 can be stopped to Step 110 without Step 109 when the 
validating control circuit 80 decides by output of said temperature sensor 
51 that the interior of the case 11 is warmed to a predetermined 
temperature for example 10.degree. C. in Step 108 during the warming-up 
period of time. Otherwise, the conveyer motor 38 can be rotated in the 
forward direction to Step 111 when the validating control circuit 80 
decides by output of the inlet sensor 40 that a bill is inserted into the 
inlet 13 during the warming-up period of time. 
As above-mentioned, the warming-up operation of the bill validator 
according to the present invention can realize that the inside of the case 
is heated to an appropriately elevated temperature and kept over a given 
temperature level. Therefore, the bill validator can always be operated in 
optimal condition, avoiding breakdown or trouble of the validator caused 
by internal freeze.