JP3059922B2 - Clothes dryer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clothes dryer for drying clothes that have been dry-cleaned using a petroleum solvent or the like.

[0002]

2. Description of the Related Art In a clothes dryer of this type, a collection drying step of drying clothes while collecting a solvent, an exhaust drying step of volatilizing a solvent remaining in the clothes to completely dry the clothes, and drying are completed. It consists of a cool-down process of cooling while loosening clothing, and a deodorizing process of removing solvent odor remaining on clothing.

[0003] In the recovery and drying step, air heated by a heater is sent into a rotating drum containing clothes in a state in which an intake port for taking in air from the outside and an exhaust port for air to the outside are closed. Evaporate the solvent that has permeated the water. Then, the air containing the solvent is sent to a cooler, and the air is cooled to liquefy and collect the solvent. The air is heated again by the heater and circulated for solvent recovery.
After the recovery of the solvent is almost completed, the process proceeds to the exhaust drying step. In the exhaust drying step, the air inlet and the air outlet are opened, the outside air is taken in from the air inlet, heated by the heater, and then sent into the rotating drum to evaporate the residual solvent in the clothes and discharge the clothes from the air outlet.

[0004] Therefore, in the recovery and drying process, the treatment is performed in a closed circulation path in the clothes dryer, and the concentration of the solvent contained in the air in the circulation path becomes maximum when passing through the rotating drum and passes through the cooler. Immediately after, it becomes the minimum. If the solvent concentration exceeds a certain value, there is a risk of ignition. Therefore, in general, the concentration of the evaporated solvent is limited by lowering the heating temperature of the heater. On the other hand, in the exhaust drying step, since the solvent concentration is originally low, the temperature of the heater is set high.

The intake and discharge of air into and from the clothes dryer are controlled by opening and closing an intake valve provided at an intake port and an exhaust valve provided at an exhaust port. However, if the intake and exhaust valves are not normally opened and closed due to a mechanical failure or the like, the following problem occurs. That is, if the intake valve or the exhaust valve is kept closed in the exhaust drying step, the heater temperature is high even if the amount of the solvent remaining in the clothes is slight, so that the volatility of the solvent increases and the solvent concentration increases. In this case, the danger of ignition increases because the solvent concentration increases when the heater temperature is high.

[0006]

In order to solve the above-mentioned problems, the applicant has already disclosed a clothes dryer capable of detecting the open / closed state of an intake valve and an exhaust valve in Japanese Patent Laid-Open No. 6-182.
No. 098. In this clothes dryer, a temperature sensor is provided at a gas outflow / outlet port of a cooler, and an open / close abnormality of an intake valve and an exhaust valve is detected based on the temperature detected by the temperature sensor. That is, for example, in the exhaust drying step, if the opening operation of the intake valve and the exhaust valve is normal, the hot air that has passed through the drum is discharged to the outside from the exhaust port provided in front of the cooler. In both cases, the temperature near the cooler outlet should be low. Conversely, if the intake valve or the exhaust valve is kept closed, hot air is circulated to the cooler side, so that the temperature at the cooler outlet rises. Therefore, if the temperature of the cooler outlet is equal to or higher than a predetermined value after a while from the recovery drying process to the exhaust drying process,
It is determined that the opening / closing operation of the intake valve or the exhaust valve is abnormal.
As described above, since the opening / closing abnormality of the intake valve and the exhaust valve is electrically detected, the structure is simple and the reliability is high.

[0007] In order to further enhance the safety of such a dryer, it is desirable to detect the temperature change as quickly and reliably as possible after shifting from the recovery drying step to the exhaust drying step. The present invention has been made in view of such a point, and is to further improve the above-mentioned conventional clothes dryer, and it is an object of the present invention to reliably detect abnormal opening and closing of an intake valve and an exhaust valve. Accordingly, it is an object of the present invention to provide a clothes dryer with further improved safety.

[0008]

Means for Solving the Problems and Embodiments of the Invention A clothes dryer according to the present invention, which has been made to solve the above problems, comprises: a rotating drum for storing clothes; A circulation path for air contained in the section, an intake port for taking in outside air into the circulation path, an exhaust port for discharging air from the circulation path to the outside, and an intake valve or the exhaust port provided at the intake port At least one of the exhaust valves provided in the, and a cooler for solvent recovery disposed in a circulation path between the intake port and the exhaust port where the rotary drum is not located, and the intake port and the rotary drum And a heater for heating the air disposed in the circulation path between them, and at least one of the intake valve and the exhaust valve is closed to collect the solvent without introducing outside air into the circulation path. While drying clothes A clothes drying step of continuously performing a recovery drying step to be performed and an exhaust drying step to dry clothes while opening both the intake valve and the exhaust valve provided with at least one of the above and introducing outside air into the circulation path. A) a temperature sensor disposed in the vicinity of the cooler; and b) at the time of transition from the recovery drying step to the exhaust drying step, after opening at least one of the intake valve and the exhaust valve, An operation control means for stopping the cooling of the cooler after a lapse of time; c) a cooling operation of the cooler which is continuously operated for the predetermined time after the opening operation of the intake valve and the exhaust valve is performed .
A predetermined value based on the amount of temperature decrease detected by the temperature sensor.
If the temperature drops, the intake valve or exhaust valve is normal
The exhaust drying operation is continued
If there is no predetermined temperature drop, the intake valve or exhaust
Judging that the valve is open, stop operation and
Abnormality detecting means for displaying a normal state.

In the clothes dryer according to the present invention, at the time of the collecting and drying step, at least one of the intake valve and the exhaust valve is closed, that is, in a state where one of the intake port and the exhaust port is open. Even so, the air pressure in the circulation path is kept slightly lower than the outside air pressure, so that the air in the circulation path is circulated in a closed state without being discharged to the outside. At this time, the heater and the cooler are operated. Therefore, the air in the circulation path is heated by the heater, and is sent into the rotating drum in which the clothes impregnated with the solvent are stored. The solvent volatilized from the clothes reaches the cooler through the circulation path together with the air, is cooled, liquefied and collected. The air is heated again by the heater and circulates.

When the process shifts from the recovery drying process to the exhaust drying process, first, both the intake valve and the exhaust valve are opened to take in outside air into the circulation path. At this time, the operation of both the heater and the cooler is continued. Therefore, the outside air flowing from the intake port is heated by the heater and sent into the rotating drum. The air that has passed through the rotating drum does not circulate in the direction of the cooler and is discharged to the outside through the exhaust port. Since the cooling operation of the cooler is continued in a state where hot air is not supplied to the vicinity of the cooler, the temperature of the air near the cooler sharply decreases. However, if both the intake and exhaust ports are not open,
The hot air that has passed through the rotating drum does not go to the exhaust port but circulates in the cooler direction, so that the temperature near the cooler does not decrease. Therefore, this temperature change is detected by the temperature sensor, and the abnormality detecting means detects a state after the opening operation of the intake valve and the exhaust valve is performed (that is, the operation control means instructs the opening operation of the intake valve and the exhaust valve). If the temperature drops by a predetermined amount or more within a certain period of time, for example, if the temperature drops by 2 ° C. or more per minute, it is determined that the intake valve and the exhaust valve have normally opened.

It is to be noted that the temperature sensor can reliably detect a temperature drop when it is located as far away from the exhaust port as possible and near the cooler. For this reason, it is preferable to arrange on the air outlet side of the cooler.

Further, the abnormality detecting means detects an opening / closing abnormality of the intake valve and the exhaust valve by judging an amount of decrease in temperature which occurs during a predetermined time after the opening operation of the intake valve and the exhaust valve, and detects the abnormality of the cooler. Is preferably stopped before a certain time has elapsed and when a time sufficient to cause a temperature drop has elapsed when the opening operation of the intake valve and the exhaust valve is normal. That is, in order to enhance safety in the present invention, it is desirable that the abnormality detecting means detects a temperature decrease within a short time as much as possible and detects an opening / closing abnormality of the valve. For this purpose, it is preferable to extend the predetermined time during which the cooler continues to operate after the valve is opened, and to operate the cooler at least until the abnormality detection means detects a valve opening / closing abnormality. However, if the operation of the cooler is continued for a long time in a state where hot air does not circulate, there is a risk of dew condensation or even freezing. For this reason, the cooler operation is not necessarily continued until the abnormality detection ends, and is stopped at an appropriate time. For example, when detecting the temperature decrease amount for one minute as described above, the predetermined time for continuing the cooler operation is set to about 30 seconds.

[0013]

According to the present invention, it is possible to quickly and reliably detect an open / close failure of an intake valve or an exhaust valve.
The danger of ignition or explosion of the solvent can be greatly reduced.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a rear cross-sectional view of a clothes dryer according to an embodiment of the present invention, FIG. 2 is a side cross-sectional view of the same, and FIG. A cylindrical rotary drum 1 having a large number of ventilation holes around it is disposed at substantially the center of the dryer main body, and clothes are put into the rotary drum 1 from a clothes input port 2. Rotating drum 1
Is supported by the main shaft 3, and a pulley 4 is attached to a tip of the main shaft 3. The pulley 4 is connected to a speed reducer 5 via a belt, and further connected to a drum drive motor 6 via a belt. An intake port 7 having an openable and closable intake valve 8 is disposed at an upper portion of the dryer main body, and air introduced into the dryer main body from the intake port 7 is supplied to the rotary drum 1, a lower ventilation path 9c, a rear ventilation path 9b, and It circulates through a series of circulation paths consisting of the upper ventilation path 9a. An exhaust port 10 is provided between the rear ventilation path 9b and the upper ventilation path 9a. The circulation of air in the circulation path is performed by rotating a fan 11 installed in the lower ventilation path 9c by a blower motor 12. In addition, a lint filter 13 for collecting lint and the like from clothes is provided in the lower ventilation path 9c.

A heater 14 is provided in an air passage extending from the intake port 7 to the rotary drum 1, and steam from a boiler (not shown) is supplied to the heater 14 via a steam valve 15. Further, a cooler 16 is provided in the upper ventilation path 9a, and a cooled refrigerant is circulated and supplied to the cooler 16 via a cooling valve 17 from a refrigerator 18 installed at the bottom of the dryer main body. In the circulation path, a first temperature sensor 19a provided on the outlet side of the cooler 16, a second temperature sensor 19b provided on the air supply side ventilation path of the rotary drum 1, and an exhaust port side ventilation path of the rotary drum 1 are provided. Three temperature sensors of the third temperature sensor 19c are arranged.

In FIG. 3, the control unit 30 mainly includes a CPU 3
1 and a memory 32. The control unit 30 has a key input signal from the operation unit 33, three temperature sensors 19a, 1
Detection signals from 9b and 19c and signals from switches and the like (not shown) are input. On the other hand, the control unit 30
An appropriate command is given to the drive circuit 35 in accordance with the execution of the operation program stored in the internal memory 32 and each of the above input signals, and the drum drive motor 6 and the blower motor 1 are provided.
2, the opening and closing of the intake valve 8, the steam valve 15, and the cooling valve 17 are controlled. In addition, the control unit 30 performs a display according to the input signal of the operation unit 33 and a display for monitoring the operation status on the display unit 34.

The operation of the clothes dryer having the configuration shown in FIGS. 1 to 3 will be described below with reference to FIGS. 4 and 5 are control flowcharts, and FIG. 6 is a diagram showing a temperature change and a cooler operation in the circulation path. In this embodiment, the operation time of the collecting and drying step is 17 minutes, and the temperature set at the outlet of the rotary drum 1 in this step, that is, the third temperature sensor 19c is 50 ° C. It is assumed that heater heating control is performed so that the difference becomes 10 ° C. The operation time of the exhaust drying step is 5 minutes, and the heater is heated so that the set temperature at the outlet of the rotary drum 1 in this step is 60 ° C. and the difference between the inlet temperature and the outlet temperature of the rotary drum 1 is 20 ° C. Control shall be performed.

When the clothes damp with the solvent after the liquid removing step of the dry cleaning are accommodated in the rotating drum 1 from the clothes inlet 2 and the drying operation is started, the control unit 30 follows the operation program stored in the memory 32. First, a recovery drying step is performed. First, the blower motor 12 and the drum drive motor 6 are turned on, the refrigerator 18 is turned on, the cooling valve 17 is opened, and the intake valve 8 is closed (step S1). At the same time, the steam valve 15 is opened (step S2).

When the blower motor 12 is rotated in a state where the intake valve 8 is closed, air is circulated in the above-described circulation path by the suction force of the rotation of the fan 11. That is,
The air heated by the heater 14 is sent into the rotating drum 1 from the ventilation holes of the rotating drum 1 and strikes the agitated clothing to volatilize the solvent permeating the clothing. The air containing the solvent escapes from the lower portion of the rotary drum 1 to the lower air passage 9c, passes through the rear air passage 9b, and the upper air passage 9a.
To 6. When the air is cooled by the cooler 16, the solvent is condensed and liquefied and collected.

After the start of the recovery / drying operation, it is determined whether or not the recovery / drying operation time has passed 17 minutes (step S3). If it has elapsed, the process proceeds to step S10. If not, the process proceeds to step S4, where the first temperature sensor 19
The temperature at the outlet of the cooler 16 is 5 ° C. based on the temperature detected by a.
It is determined whether or not: That is, in the normal recovery and drying operation, since the intake valve 8 is closed and air is not introduced from the outside, the hot air that has passed through the rear ventilation passage 9b
And is circulated to the cooler 16 side without being discharged. Therefore, the temperature at the outlet of the cooler 16 does not become extremely low. However, if the intake valve 8 is left open due to a failure, outside air flows in from the intake port 7, so that the hot air that has passed through the rear ventilation path 9 b is discharged to the outside from the exhaust port 10. In this case, since the cooler 16 continues to be cooled without the hot air circulating, the temperature at the outlet of the cooler 16 becomes abnormally low. Therefore, when the temperature detected by the first temperature sensor 19a becomes 5 ° C. or less, it is determined that the operation of the intake valve 8 is abnormal, the process proceeds to step S28, and the operation is stopped. Is displayed (step S29).

If the temperature at the outlet of the cooler 16 is higher than 5 ° C. in step S4, the temperature at the drum outlet is 55 ° C. or higher or the temperature at the drum inlet and outlet based on the temperatures detected by the second temperature sensor 19b and the third temperature sensor 19c. It is determined whether the difference is 10 ° C. or more (step S5). If the drum outlet temperature is 55 ° C. or more or the temperature difference is 10 ° C. or more, the process proceeds to step S6, and the steam valve 15 is closed. As a result, the heating of the heater 14 is weakened. If the drum outlet temperature is less than 55 ° C. and the temperature difference is less than 10 ° C., the process returns to step S3 and repeats the above processing. After the steam valve 15 is closed in step S6, the processes of steps S7 and S8 corresponding to steps S3 and S4 are executed. In step S9, the temperature at the drum outlet is 5
It is determined whether the temperature difference between the inlet and the outlet of the drum is 3 ° C. or less and the temperature difference is 8 ° C. or less. If the drum outlet temperature is 53 ° C. or less and the temperature difference is 8 ° C. or less, the process returns to step S2, and the steam valve 15 is opened again to start heating the heater 14. On the other hand, if the drum outlet temperature is higher than 53 ° C. or the temperature difference is higher than 8 ° C., the process returns to step S7 with the steam valve 15 closed, and the above processing is repeated.

By the above processing, the temperature difference between the inlet and the outlet of the drum is maintained at about 10 ° C. as shown in FIG. 6A, and the temperature at the outlet of the drum is also the upper limit temperature (in this case, 55 ° C.). ) Below. As a result, the concentration of the solvent in the circulation path is kept almost constant at a value without danger of ignition. Then, when the collecting and drying operation time has passed 17 minutes, the collecting and drying step is ended, and the process proceeds to the next exhaust drying step.

After the start of the exhaust drying step, if the steam valve 15 is closed (step S10), the intake valve 8 is also opened (step S11). When the blower motor 12 is rotated with the intake valve 8 opened, the outside air constantly flows from the intake port 7, and the outside air heated by the heater 14 is sent into the rotary drum 1 and hits the garment to be stirred. The remaining solvent is volatilized. This hot air escapes from the lower part of the rotary drum 1 to the lower air passage 9c,
The air is discharged from the exhaust port 10 to the outside through the rear ventilation passage 9b.

After 30 seconds have passed since the intake valve 8 was opened (step S12), the cooling valve 17 is closed and the cooling of the cooler 16 is stopped (step S13). During this 30 seconds, the hot air that has passed through the inside of the rotary drum 1 does not pass through the upper air passage 9a and does not hit the cooler 16, but the cooler 16 keeps operating, so that the air near the cooler 16 is cooled. Therefore, as shown in FIG. 6A, the temperature detected by the first temperature sensor 19a (cooler outlet temperature) rapidly decreases immediately after the start of the exhaust drying operation.

It is determined whether or not one minute has elapsed since the opening of the intake valve 8 (step S14). If not, it is determined based on the temperatures detected by the second temperature sensor 19b and the third temperature sensor 19c. Then, it is determined whether the drum outlet temperature is 60 ° C. or higher or the temperature difference between the drum outlet and the inlet is 20 ° C. or higher (step S15). If one minute has elapsed in step S14, the process proceeds to step S20. If the drum outlet temperature is 60 ° C. or more or the temperature difference is 20 ° C. or more, the steam valve 15 is closed to weaken the heating of the heater (step S16), and the drum outlet temperature is less than 60 ° C. and the temperature difference is less than 20 ° C. If there is, return to step S14 and repeat the above processing. After closing the steam valve 15 in step S16, it is determined again whether one minute has elapsed (step S17), and if it has elapsed, the process proceeds to step S20. If one minute has not elapsed, the temperature at the drum outlet is 58 ° C. or lower and the temperature difference between the drum inlet and outlet is 18 °.
° C (step S18), and if so, the steam valve 15 is opened (step S1).
9) Return to step S14 and repeat the above processing.

If one minute has elapsed in steps S14 and S17, the amount of change in the cooler outlet temperature for one minute, Δ, based on the temperature detected by the first temperature sensor 19a.
T is calculated (step S20). Then, it is determined whether or not the temperature change amount ΔT is 2 ° C. or more (step S
21) If the temperature is equal to or higher than 2 ° C., it is determined that the opening operation of the intake valve 8 is normal, and the process proceeds to step S22 to continuously perform the exhaust drying operation. On the other hand, if it is lower than 2 ° C., it is determined that the intake valve 8 is kept closed or insufficiently opened, and the process proceeds to step S28 to stop the operation and display an abnormality of the intake valve opening. (Step 29).

In step S23, the exhaust drying operation time is 5
It is determined whether or not the time has elapsed. If the time has elapsed, the exhaust drying operation is terminated and the process proceeds to the next cool-down step.
If five minutes have not elapsed, the process proceeds to step S24, which corresponds to step S15. Step S22-
The processing of S27 is the same as the above-described steps S14 to S19 except for the determination criteria of the elapsed time.

By the above processing, in the exhaust drying step, the temperature difference between the inlet and the outlet of the drum is maintained at about 20 ° C. as shown in FIG. (In this case, 65 ° C.) or less. As a result, the concentration of the solvent in the circulation path is kept almost constant at a value without danger of ignition. Then, when the exhaust drying operation time has passed 5 minutes, the exhaust drying step is completed, and the process proceeds to the next cool-down step.

In the cool-down step, the intake valve 8 is closed again, the cooling valve 17 is opened, and the steam valve 15 is closed. That is, the heating of the heater is stopped, and the cool air cooled by the cooler 16 circulates in the circulation path. The operation time of the cool-down process is 2.5 minutes. In the last deodorization step, the intake valve 8 is opened, and the cooling valve 1 is opened.
7 is a closed state, in which only the replacement of air by the fan 11 is performed.

In the above embodiment, the exhaust port 10 is not provided with an openable / closable exhaust valve and is kept open. By providing an openable and closable exhaust valve and controlling it to open and close simultaneously with opening and closing of the intake valve 8, the inside of the dryer may be made to be completely sealed.

When the cooling of the cooler is stopped, the operation of the refrigerator itself may be stopped in addition to closing the cooling valve. Further, the values of the operation time, the temperature, and the like in the above-described embodiment are merely examples, and can be appropriately changed.

[Brief description of the drawings]

FIG. 1 is a rear sectional view of a clothes dryer according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the clothes dryer of the embodiment of FIG.

FIG. 3 is an electrical configuration diagram of the clothes dryer according to the embodiment of FIG. 1;

FIG. 4 is a control flowchart of the clothes dryer of the embodiment.

FIG. 5 is a control flowchart of the clothes dryer of the embodiment.

FIG. 6 is a diagram showing a temperature change and a cooler operation in a circulation path of the clothes dryer of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotary drum 7 ... Intake port 8 ... Intake valve 9a ... Upper ventilation path 9b ... Rear ventilation path 9c ... Lower ventilation path 10 ... Exhaust port 14 ... Heater 15 ... Steam valve 16 ... Cooler 17 ... Cooling valve 19a, 19b, 19c ... Temperature sensor 30 ... Control unit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-182098 (JP, A) JP-A-6-343797 (JP, A) JP-A-6-15093 (JP, A) JP-A-5-15093 277287 (JP, A) JP-A-6-296795 (JP, A) JP-A-4-279194 (JP, A) JP-A-4-236995 (JP, A) JP-A-63-288194 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) D06F 58/28

Claims (3)

(57) [Claims] A rotating drum for accommodating clothes, a circulation path of air including a part of the rotating drum, an air inlet for taking in outside air into the circulation path, and an external air from the circulation path. Circulation between the exhaust port for exhausting the air, at least one of an intake valve provided at the intake port or an exhaust valve provided at the exhaust port, and the intake port and the exhaust port where the rotary drum is not located A cooler for recovering a solvent disposed in a passage, and a heater disposed in a circulation passage between the intake port and the rotary drum for heating air, and at least one of the intake valve and the exhaust valve A collection and drying step for drying clothes while performing solvent recovery without closing one of them and introducing outside air into the circulation path, and opening both an intake valve and an exhaust valve provided with at least one of the two. The circulation A clothes dryer that continuously performs an exhaust drying step for drying clothes while introducing outside air into the clothes drying apparatus, comprising: a) a temperature sensor disposed near the cooler; b) a collection drying step to an exhaust drying step. An operation control means for stopping the cooling of the cooler after a predetermined time has elapsed after opening the intake valve and the exhaust valve provided with at least one of them at the time of the transition; c) opening operation of the intake valve and the exhaust valve After the cooling operation, the cooling operation of the cooler, which is continuously operated for the predetermined time, is performed .
A predetermined value based on the amount of temperature decrease detected by the temperature sensor.
If the temperature drops, the intake valve or exhaust valve is normal
The exhaust drying operation is continued
If there is no predetermined temperature drop, the intake valve or exhaust
Judging that the valve is open, stop operation and
A clothes dryer, comprising: abnormality detecting means for displaying a normal state . 2. The clothes dryer according to claim 1, wherein the temperature sensor is arranged on a gas outlet side of the cooler. 3. The clothes dryer according to claim 1, wherein the abnormality detecting means determines the amount of temperature decrease occurring during a predetermined time after the opening operation of the intake valve and the exhaust valve is performed. When a predetermined time set in the operation control means detects an opening / closing abnormality of the valve or the exhaust valve, and the predetermined time is not elapsed, and when the opening operation of the intake valve and the exhaust valve is normal, the temperature is determined. A clothes dryer characterized by a time sufficient to cause a drop.