Drum
Door Control
The drum door is opened and closed by the door grabber, which is positioned by an actuator driven by a small DC brush motor. A mechanical interlock prohibits the drum door from latching closed if garments get caught in the door opening. With the door unable to close, the drum will stall, which will be sensed by the motor control module and corrective action will occur.
The drum door is opened and closed by the door grabber, which is positioned by an actuator driven by a small DC brush motor. A mechanical interlock prohibits the drum door from latching closed if garments get caught in the door opening. With the door unable to close, the drum will stall, which will be sensed by the motor control module and corrective action will occur.
After
Start/Pause is pressed when the dryer is waiting with the drum door open:
1. The lid will lock.
2. The sensor module assumes the drum door is open at “Home” and rotates the drum at 5 RPM in the drum door close direction. If it is “Home” and the grabber lowered, the door will close at 78 degrees away from “Home”. Note: If the door is closed and the grabber lowered, the drum will simply rotate with a slight rubbing noise of the grabber on the drum.
1. The lid will lock.
2. The sensor module assumes the drum door is open at “Home” and rotates the drum at 5 RPM in the drum door close direction. If it is “Home” and the grabber lowered, the door will close at 78 degrees away from “Home”. Note: If the door is closed and the grabber lowered, the drum will simply rotate with a slight rubbing noise of the grabber on the drum.
3.
If the motor stalls after the drum has moved at least 42 degrees, a “Clothes
Jammed” fault will be internally flagged and the drum will reverse and the door
will open before trying to close again. After three unsuccessful attempts, the
drum door will open, the lid will be unlocked and the relevant User Warning
will occur.
4. At the “Retract Grabber Position”, 142 degrees from “Home”, the sensor module begins moving away the grabber.
• If a fault is detected during the actuator movement, the operation of the actuator will be checked. The drum will stop and an attempt will be made at moving the actuator back to lower the door grabber.
• If a fault is again detected, a maximum of five attempts are made at moving the grabber, alternating the direction with each attempt, until finally the dryer will display the relevant fault code and remain in the stationary position with the lid unlocked. If however the actuator is operated correctly, the grabber is left in the retracted position. 5. When the grabber is confirmed to have retracted, the drum is sped up to 47 RPM and the sensor module will begin or continue the normal drying operation.
4. At the “Retract Grabber Position”, 142 degrees from “Home”, the sensor module begins moving away the grabber.
• If a fault is detected during the actuator movement, the operation of the actuator will be checked. The drum will stop and an attempt will be made at moving the actuator back to lower the door grabber.
• If a fault is again detected, a maximum of five attempts are made at moving the grabber, alternating the direction with each attempt, until finally the dryer will display the relevant fault code and remain in the stationary position with the lid unlocked. If however the actuator is operated correctly, the grabber is left in the retracted position. 5. When the grabber is confirmed to have retracted, the drum is sped up to 47 RPM and the sensor module will begin or continue the normal drying operation.
When Pause is pressed or the drying is completed:
1. If the drum is rotating in the Close direction, then it will be reversed and the drum speed will be set at 20 RPM, at which speed the position of the drum is verified using the tacho “Gap” as its reference. If however the drum was moving in the open direction, its position may have already being verified at the higher speed, but if not, will be set to slow down to 20 RPM until the position is verified. If within 40 seconds the sensor module is unable to verify its position, either because no “Gap” of sufficient arc has been detected or a correct count for a complete revolution of the drum cannot be obtained, then a fault code will be displayed.
2. Once the position is known, the drum speed begins to slow to 5 RPM. Provided the drum speed has reduced to at least 18 RPM when the drum position is 132 degrees from the extended door grabber position (210 degrees from “Home”), the lowering of the grabber begins.
3.
As the bridges approach the lowered door grabber, wings on each side of the
grabber enter the bridge channels. If the wings do not enter the channels, the
grabber will be unable to open the drum door (refer to the diagram below). As the drum continues to rotate, the
engagement ribs attached to the door grabber unlatch the drum door hinge arms,
lifting them out of the channel slots. The hinge arms are raised by
details on the dAs the drum reaches the fully opened position, details on the drum bridges hit the door grabber, causing the motor to stall and the drum to stop. The drum is now in a fully opened position, where the user can load or unload garments from the dryer.oor grabber to the top face of the bridge channels. The drum continues to rotate in the opening direction, while the drum door is held stationary by the door grabber.
details on the dAs the drum reaches the fully opened position, details on the drum bridges hit the door grabber, causing the motor to stall and the drum to stop. The drum is now in a fully opened position, where the user can load or unload garments from the dryer.oor grabber to the top face of the bridge channels. The drum continues to rotate in the opening direction, while the drum door is held stationary by the door grabber.
As
the drum reaches the fully opened position, details on the drum bridges hit the
door grabber, causing the motor to stall and the drum to stop. The drum is now
in a fully opened position, where the user can load or unload garments from the
dryer. The dryer electronics can determine whether the drum has reached the
correct position by way of the optical sensor attached to the Sensor board,
which uses the dimples on the drum end outlet to determine the drum position.
4. Provided there is no failure in extending the grabber, the drum door will be opened. However, if a failure is detected in the actuator’s movement, the drum will immediately stop. The dryer will then attempt to retract the grabber. If the grabber is successfully retracted, the sequence will repeat from step 1 of this opening sequence. However, if the actuator fails to successfully move the grabber after repeated attempts, the sensor module will stop the drum in its closed state and a fault code will be displayed. Five attempts are made to open the drum door before flagging the fault.
5. The lid lock will be released.
4. Provided there is no failure in extending the grabber, the drum door will be opened. However, if a failure is detected in the actuator’s movement, the drum will immediately stop. The dryer will then attempt to retract the grabber. If the grabber is successfully retracted, the sequence will repeat from step 1 of this opening sequence. However, if the actuator fails to successfully move the grabber after repeated attempts, the sensor module will stop the drum in its closed state and a fault code will be displayed. Five attempts are made to open the drum door before flagging the fault.
5. The lid lock will be released.
When
the power is first switched on or restored after interruption:
In normal circumstances where the previous cycle was completed successfully, when power is reapplied to the product, the sensor module will assume the door is open and the machine is at rest. In all other cases it will either continue operating or return to the “home” position so that the drum door is open and the lid is unlocked. If for some reason the drum door is not open, then the operator will need to first start, then pause the machine to return it to its drum open position. When the dryer recommences operation, the sensor module must allow for the situation where the drum door may be part way through an opening or closing sequence. In order to do this without the risk of damaging any of the mechanical parts, the sensor module executes the following sequence:
1. Moves the drum in the open direction to check if the user has manually opened the drum door, and if found so, will stop and assume the normal off position.
2. If not “Home”, moves the drum so as to close the door, moving as far as would normally be required to close the door from the “Home” (fully open) position.
In normal circumstances where the previous cycle was completed successfully, when power is reapplied to the product, the sensor module will assume the door is open and the machine is at rest. In all other cases it will either continue operating or return to the “home” position so that the drum door is open and the lid is unlocked. If for some reason the drum door is not open, then the operator will need to first start, then pause the machine to return it to its drum open position. When the dryer recommences operation, the sensor module must allow for the situation where the drum door may be part way through an opening or closing sequence. In order to do this without the risk of damaging any of the mechanical parts, the sensor module executes the following sequence:
1. Moves the drum in the open direction to check if the user has manually opened the drum door, and if found so, will stop and assume the normal off position.
2. If not “Home”, moves the drum so as to close the door, moving as far as would normally be required to close the door from the “Home” (fully open) position.
3.
The sensor module then operates the grabber and leaves it in the retracted
position.
4. Provided the grabber was successfully retracted, the drum will continue rotating in the Close direction; ramp up to full speed, and the dryer will continue its cycle.
4. Provided the grabber was successfully retracted, the drum will continue rotating in the Close direction; ramp up to full speed, and the dryer will continue its cycle.
Heater
Control.
The heaters are controlled in response to the selected drying cycle chosen and also according to other operational requirements such as reversing and overheating. The heater housing is fitted with two elements
that supply approximately 5 kW of heat when both are on. There is a 3.6kW and a 1.4kW element that are used at various times depending on the cycle chosen and the drum/fan direction. When drying, the heater is only switched on when the drum is up to speed. Because of the time it takes for the element to cool down after switching off, the larger element in the electric model is switched off a few seconds before
stopping to reverse, to prevent excessive heat entering the drum.
The heaters are controlled in response to the selected drying cycle chosen and also according to other operational requirements such as reversing and overheating. The heater housing is fitted with two elements
that supply approximately 5 kW of heat when both are on. There is a 3.6kW and a 1.4kW element that are used at various times depending on the cycle chosen and the drum/fan direction. When drying, the heater is only switched on when the drum is up to speed. Because of the time it takes for the element to cool down after switching off, the larger element in the electric model is switched off a few seconds before
stopping to reverse, to prevent excessive heat entering the drum.
The
software in the motor control module responds to the switching on and off of
the heater as requested by the sensor module. It also monitors the automatic
thermostat on the heater housing for excessive restriction of airflow, and if
detected, will set a User Warning but continue the drying cycle until the end
of the cycle when the warning will reset. If the User Warning occurs, the
drying will take a longer time to complete and the load will possibly end up a
little damp. Each cycle has a
temperature limit, as defined in the tables in Section 5.12, as measured in the
exhaust air. After switching off at the limit, the temperature has a hysteresis
of 5 degrees below these temperatures when the heat source switches back on.
Note: During heating, if the temperature exceeds the limits for the particular cycle, the heat is turned off and can significantly reduce the heating time.
Note: During heating, if the temperature exceeds the limits for the particular cycle, the heat is turned off and can significantly reduce the heating time.
Cycle
times can be affected by a number of factors including:
* The cycle chosen
* Load size
* Size of items
* Type of fabric
* Load wetness
* Venting method
* Location of dryer
* Condition of exhaust ducts
* Environmental conditions (temperature, humidity, etc)
* The cycle chosen
* Load size
* Size of items
* Type of fabric
* Load wetness
* Venting method
* Location of dryer
* Condition of exhaust ducts
* Environmental conditions (temperature, humidity, etc)
Auto
Sensing
When wet or damp clothes are loaded into a dryer they are partially saturated with water which is a relatively good conductor of electricity. In the Intuitive dryer, sensor bars (located beneath the lint bucket) are used to measure the conductivity. When moisture in the clothes touches across the sensor bars their conduction is measured. As the clothes dry they become less conductive and it is this measurement that is used to calculate the dryness of the clothes load. Large loads will brush against these sensor bars more frequently than small loads, and this strike count is used to help determine the dryness of different sized loads. Different fabrics retain moisture differently; a thick towel containing a lot of moisture will often conduct the same as a light synthetic garment containing very little. It is this difference in fabric characteristics plus the initial unknown moisture content that makes the calculation of dryness reasonably complex.
When wet or damp clothes are loaded into a dryer they are partially saturated with water which is a relatively good conductor of electricity. In the Intuitive dryer, sensor bars (located beneath the lint bucket) are used to measure the conductivity. When moisture in the clothes touches across the sensor bars their conduction is measured. As the clothes dry they become less conductive and it is this measurement that is used to calculate the dryness of the clothes load. Large loads will brush against these sensor bars more frequently than small loads, and this strike count is used to help determine the dryness of different sized loads. Different fabrics retain moisture differently; a thick towel containing a lot of moisture will often conduct the same as a light synthetic garment containing very little. It is this difference in fabric characteristics plus the initial unknown moisture content that makes the calculation of dryness reasonably complex.
COMPONENTS
Element Assembly 240V 3.6 kW
Two sets of Nichrome wire elements linked in parallel between
Mica plates. A ceramic insulator is used to support the element
assembly in the housing.
Cold Resistance 13.5 Ohms
Current 15 Amps
Power 3.6 kW
Voltage 240 Volts.
Element Assembly 240V 3.6 kW
Two sets of Nichrome wire elements linked in parallel between
Mica plates. A ceramic insulator is used to support the element
assembly in the housing.
Cold Resistance 13.5 Ohms
Current 15 Amps
Power 3.6 kW
Voltage 240 Volts.
Element Assembly 240V 1.4 kW
Cold Resistance 37 Ohms
Current 5.8 Amps
Power 1.4 kW
Voltage 240 Volts
Thermostat Cutout – Automatic
Reset
Type SPST
Trip Temperature 70°C ± 3o
Reset Temperature 55°C ± 4o
Thermostat
Cutout – Manual Reset
Type SPST 30 Amps/240 Volts AC
Trip Temperature 100oC ± 6
Type SPST 30 Amps/240 Volts AC
Trip Temperature 100oC ± 6
Motor
– 3 Phase 240W
Voltage Rated 190 Volts AC 85 Hz
Power 240 Watts
Current 1.6 Amps
Speed 2340 RPM
Resistance Across Any
Two Terminals of Plug 9.6 Ohms
Voltage Rated 190 Volts AC 85 Hz
Power 240 Watts
Current 1.6 Amps
Speed 2340 RPM
Resistance Across Any
Two Terminals of Plug 9.6 Ohms
Exhaust
Temperature Sensor
Loom
Resistance (+10%) at Various Ambients
0oC 33 kOhms
10oC 20 kOhms
20oC 12 kOhms
30oC 8 kOhms
40oC 5 kOhms
Loom
Resistance (+10%) at Various Ambients
0oC 33 kOhms
10oC 20 kOhms
20oC 12 kOhms
30oC 8 kOhms
40oC 5 kOhms
Lid
Lock
Resistance range 63 Ohms +/- 10 Ohms @ 20oC
Safety extra low voltage.
Resistance range 63 Ohms +/- 10 Ohms @ 20oC
Safety extra low voltage.
Motor Control Module
Sensor Module
Display Module
