JP2008125745A - Dry cleaner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly safe dry cleaner which ensures safety with no danger of ignition or the like even if microcomputer runaway or the like occurs, and the dry cleaner which ensures safety insurance in the drying process. <P>SOLUTION: A relay sequence control circuit 71 includes a serial connection of a first valve V27 to be controlled, a first switch 77 for controlling the turn-on of the first valve V27 and a second contact 76a provided in a second relay 76. A detection circuit 79 for controlling the second contact 76a is connected to this serial connection. Thus, the first valve V27 is maintained in an inactive state irrespective of a first switch 77 turn-on control performed by a control part 81 until the detection circuit 79 performs a predetermined operation to turn on the second contact 76a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dry cleaner, and more particularly to a dry cleaner that performs washing, draining and drying using a flammable solvent.

Conventionally, laundry is washed with a flammable solvent such as petroleum solvent, the solvent is removed from the laundry after washing, and hot air heated by a heater is applied to the washed laundry. There is known a dry cleaner that dries laundry by bathing and evaporating the solvent.
By the way, since petroleum-based solvents are highly flammable, if the concentration of solvent gas evaporated from the laundry is high during the drying of the laundry, the heat of the heater is ignited as a source of ignition to the solvent gas, and there is a risk of ignition accidents. There is a risk of explosion.

  Therefore, as a dry cleaner for preventing such an accident, a drum for storing laundry and performing washing, draining and drying, a circulation air passage for circulating the air in the drum, and a circulation air Steam heating type drying heater for heating the air flowing through the passage, a steam valve that is opened and closed to supply steam to the drying heater, and the temperature of the gas supplied to the drum provided in the circulation air passage A dry cleaner comprising a drum inlet temperature sensor, a drum outlet temperature sensor for measuring the temperature of a gas that has passed through the drum, and a control unit that controls the steam valve and each of the temperature sensors. Is known (for example, Patent Document 1).

  In the drying process, the drum outlet temperature changes depending on the amount of solvent contained in the laundry. That is, when the amount of solvent contained in the laundry is large, the volatilization amount is relatively large and the drum outlet temperature is relatively low. Increasing the drum inlet temperature when the drum outlet temperature is low, that is, increasing the heating by opening the steam valve increases the amount of solvent volatilization from the laundry, resulting in a safe value (for example, the solvent is gasoline 5). In the case of No. 2, air with a solvent gas temperature exceeding 0.6 vol% is generated in the drum, and there is a risk of ignition.

In the dry cleaner described in Patent Document 1, in order to avoid the above danger, the drum outlet temperature is monitored by a microcomputer, the opening and closing of the steam valve is controlled, the temperature of the circulating air supplied from the drum inlet temperature is controlled, and the washing is performed. The amount of volatilization of the solvent from the product becomes too large so that the solvent gas concentration does not exceed a safe value.
JP 2005-218881 A

  However, in the dry cleaner described in Patent Document 1, for example, when a so-called microcomputer runaway occurs due to malfunction of the control unit, the steam valve is not controlled, and the concentration of the solvent gas is controlled. May not be possible. When this happens, the concentration of the solvent gas in the drum increases, and there is a risk that the solvent gas will ignite as a drying heater.

The present invention has been made based on such a background, and a main object of the present invention is to provide a safer dry cleaner that does not pose a danger of ignition or the like even if a microcomputer runaway occurs.
Another object of the present invention is to provide a dry cleaner that ensures the safety in the drying process.

  The invention described in claim 1 is a dry cleaner that performs washing, draining and drying of laundry using a flammable solvent, and is a treatment tank for storing laundry and performing washing, draining and drying A circulation air passage for taking out air in the treatment tank, circulating the closed flow path for drying and returning it to the treatment tank, heating means for heating the air flowing through the circulation air path, and the heating Control means for controlling the operation of the means to execute a drying process; signal output means for outputting an end signal in response to the completion of a predetermined liquid removal process in the processing tank; and the end signal output And a safety circuit that keeps the heating means in an inoperable state regardless of the control of the control means.

  The invention described in claim 2 includes the outer tub formed in a liquid-tight manner and the laundry housed therein by being rotatably provided in the outer tub and rotating. An inner tank that drains the solvent by centrifugal force, and a drive motor for rotating the inner tank, and the signal output means rotates the inner tank or the drive motor at a predetermined rotational speed or higher. The dry cleaner according to claim 1, further comprising a mechanism for outputting the end signal when the rotation has elapsed for a predetermined time.

  According to a third aspect of the present invention, the signal output means is a switch that is turned on when the rotational speed of the inner tub or the drive motor is equal to or higher than a predetermined rotational speed, and starts timing by turning on the switch. The dry cleaner according to claim 2, further comprising: a timer that measures a time during which the signal is ON and outputs the end signal when the time is measured for a predetermined time.

  According to a fourth aspect of the present invention, the heating means includes a heat exchanger that exchanges heat with the air flowing through the circulation air passage, and a steam supply means that supplies steam to the heat exchanger, and the safety circuit The dry cleaner according to any one of claims 1 to 3, wherein steam is not supplied from the steam supply means to the heat exchanger in order to keep the heating means in an inoperable state. It is.

The invention according to claim 5 is characterized in that the steam supply means includes a steam supply path for supplying steam and a valve for closing and opening the steam supply path, and the safety circuit includes the heating means. The dry cleaner according to claim 4, wherein the valve is normally closed in order to keep it in an inactive state.
According to a sixth aspect of the present invention, a plurality of the steam supply passages are provided, and a valve is interposed in each steam supply passage, so that the safety circuit keeps the heating means in an inoperable state. The dry cleaner according to claim 5, wherein only the predetermined valve is normally closed.

  According to the first aspect of the present invention, in the state where the end signal in response to the end of the predetermined liquid removal processing in the processing tank is not output by the signal output means, the safety circuit is provided regardless of the control of the control means. By this, the heating means is kept in an immovable state. These signal output means are constituted by hardware different from the control means (such as a microcomputer), and an end signal can be obtained without depending on the control means. Therefore, it is possible to operate the heating means only after the predetermined liquid removal process is completed.

  In general, the solvent gas concentration during the drying process greatly depends on the amount of solvent contained in the laundry and the temperature of the air exposed to the laundry, the more solvent contained, the higher the air temperature. The solvent gas concentration tends to increase. Therefore, if the amount of the solvent contained in the laundry is set to a certain amount or less in the liquid removal treatment, the amount of the solvent that volatilizes in the drying process is small, and even if the air temperature is high, the solvent gas concentration increases to a certain value or more. There is no.

  For example, the lower limit flammability concentration, which is the lower limit concentration that the solvent gas may ignite, is 0.8 vol%, the amount of solvent contained in the laundry is “A”, and the laundry containing the solvent below “A” The solvent gas concentration is maintained at 0.8 vol% or less even when it is overheated (hereinafter referred to as “A” unless otherwise specified). In the present invention, if the predetermined liquid removal treatment is defined as, for example, “a treatment for removing liquid so that the amount of solvent contained in the processed laundry is equal to or less than“ A ””, the amount of solvent contained in the laundry The heating means can be operated only after the temperature becomes “A” or less.

  As a result, the control means runs out of control during the operation of the heating means. For example, even if the heating means falls into an uncontrollable state and the air in the circulation air passage is overheated, the amount of solvent contained in the laundry becomes “A” or less. Therefore, the solvent gas concentration does not exceed the lower flammability limit concentration. As a result, it is possible to provide a safer dry cleaner that ensures the safety in the drying process and does not cause danger such as ignition.

  According to the second aspect of the present invention, the signal output means is provided with a mechanism for outputting an end signal when the inner tub or the drive motor rotates at a predetermined rotational speed or more and the rotation has passed for a predetermined time. Yes. In the invention according to claim 2, the predetermined rotation speed and the rotation time at the rotation speed are, for example, “the amount of the solvent contained in the laundry after the treatment can be set to“ A ”or less, and the rotation speed thereof” If the “rotation time at the rotation speed” is determined, it is possible to prevent the solvent gas concentration from rising above a certain value by a simple method of simply detecting the rotation speed and rotation time of the inner tank.

  According to the third aspect of the present invention, the signal output means includes a switch that is turned on when the rotational speed of the inner tank or the drive motor is equal to or higher than a predetermined rotational speed, and starts counting when the switch is turned on. And a timer that outputs an end signal when the time is measured for a certain time. Therefore, it is possible to prevent the solvent gas concentration from rising above a certain value by a simple method of simply controlling the switch and the timer.

  According to the invention described in claim 4, the heating means includes a heat exchanger for exchanging heat with the air flowing through the circulation air passage, and a steam supply means for supplying steam to the heat exchanger. In order to keep this in an inoperable state, the safety circuit prevents the steam from being supplied from the steam supply means to the heat exchanger. As a result, the steam is supplied to the heat exchanger and the air flowing through the circulation air passage is heated only after the predetermined liquid removal process is completed. As a result, the control means runs out of control during the supply of steam. For example, even if a large amount of steam is supplied from the steam supply means and the temperature of the heat exchanger rises rapidly, the amount of solvent contained in the laundry becomes “A” or less. Therefore, it is possible to prevent the solvent gas concentration from rising above a certain value.

According to the invention described in claim 5, the steam supply means includes a steam supply path for supplying steam and a valve for closing and opening the steam supply path, and the valve is provided by a safety circuit. Always closed. According to this configuration, it is possible to prevent the solvent gas concentration from rising above a certain value by simple control in which the valve is always closed.
According to the sixth aspect of the present invention, a plurality of steam supply passages are provided, and each steam supply passage is provided with a valve, and only a predetermined valve of the valves is provided by the safety circuit. Always closed. In the invention described in claim 6, for example, a predetermined valve is defined as “a valve that may increase the solvent gas concentration to a concentration exceeding the lower flammability limit concentration by being opened”, and only the valve is determined. If it is normally closed, it is possible to prevent the solvent gas concentration from rising above a certain value. Further, the other valves do not need to be kept in an immovable state by the safety circuit, and it is not necessary to provide an extra device, so that cost can be saved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
<Appearance structure of dry cleaner>
FIG. 1 is a front perspective view of a main part of a dry cleaner 1 according to an embodiment of the present invention. In addition, when referring to a direction, the illustrated direction arrow is referred to (the same applies to other drawings).

Referring to FIG. 1, this dry cleaner 1 is for business use, for example, and includes a substantially rectangular parallelepiped main body 2 and a tank / filter kit 3 (see FIG. 2).
The main body 2 includes a substantially frame-shaped frame 2a, and an outer tub 4 and a drum 5 (inner tub) accommodated in the outer tub 4 are provided in the frame 2a. The frame 2a is fixed to the ground. In addition, an operation panel 2b is attached to a position above the outer tub 4 in the front side surface portion of the frame 2a, specifically near the position of the user's eyes. By operating an operation button 66 (described later) of the operation panel 2b, it is possible to cause the dry cleaner 1 to execute a desired operation. The display panel 67 (described later) of the operation panel 2b indicates the operation status of the dry cleaner 1. Is displayed.

  The outer tub 4 is formed in a substantially rectangular parallelepiped shape, and a substantially cylindrical space is formed therein. A front side wall of the outer tub 4 is formed with an outer tub opening 4 a having a circular shape in front view and communicating with the inside of the outer tub 4. An annular rim 4b made of metal is fitted into the outer tub opening 4a along the peripheral edge thereof. An annular packing 4c is attached to the front edge of the inner peripheral edge of the rim 4b. A hinge 4d is provided at the left end of the rim 4b, and an engaged projection 4e is provided at the right end of the rim 4b. A door (not shown) is attached to the hinge 4d, and this door (not shown) can rotate around the rotation axis of the hinge 4d to open and close the outer tub opening 4a. . Further, the door (not shown) is provided with an engaging projection (not shown) on the opposite side to the side attached to the hinge 4d, and the door (not shown) serves as the outer tank opening. When the engagement protrusion (not shown) engages with the engagement protrusion 4e of the rim 4b when the door 4a is closed, the door (not shown) is locked with the outer tub opening 4a closed. The

Moreover, the outer tank 4 is connected with the flame | frame 2a via the damper 2c in the four corners of the bottom face. Therefore, even if the outer tub 4 vibrates during the operation of the dry cleaner 1, the vibration is alleviated by the damper 2c, so that the vibration is prevented from being transmitted around the dry cleaner 1 through the frame 2a. .
The drum 5 is formed in a hollow, substantially cylindrical shape, and is arranged so that its central axis extends in a substantially horizontal direction, specifically in the front-rear direction. Further, a drum motor 21 (see FIG. 3) connected to the central shaft is disposed behind the drum 5, and when the drum motor 21 rotates, the power is transmitted to the drum 5 through the central shaft. As a result, the drum 5 rotates. A drum opening 5 a communicating with the inside of the drum 5 is formed on the front side wall of the drum 5 at a position corresponding to the outer tank opening 4 a. The drum opening 5a faces the outer tub opening 4a in the front-rear direction. Therefore, the door (not shown) can be opened, and the laundry can be accommodated in the drum 5 through the outer tub opening 4a and the drum opening 5a. In addition, a plurality of baffles 5 b protruding toward the central axis direction are provided on the inner peripheral surface of the drum 5.
<Internal configuration of dry cleaner>
FIG. 2 is a piping system diagram of the dry cleaner 1. Below, with reference to FIG. 2, the internal structure of the dry cleaner 1 is explained in full detail.

  The outer tub 4 described above is provided with an air inlet 6 for introducing air into the drum 5 and an air outlet 7 for discharging the air in the drum 5, and the air outlet 7 and the air inlet 6. They are connected by a circulation path 8 (circulation wind path). That is, the circulation path 8 has an air inlet 6 and an air outlet 7 and can be said to be a closed path (closed flow path) that connects between the air outlet 7 and the air inlet 6.

  The dry cleaner 1 is a device that performs dry cleaning using a dedicated combustible solvent (for example, petroleum solvent). Although dry cleaning has advantages such as less shrinkage of the laundry and easy removal of oil stains compared to washing the laundry with water, it is desirable that the solvent to be used should not be released into the environment as much as possible. Therefore, in this embodiment, the solvent is all recovered.

  That is, at the time of washing, a certain amount of solvent supplied from a tank 31 described later is stored in the outer tub 4 and washing is performed. After washing, the solvent is recovered from the outer tub 4 to the tank 31. Further, the drum 5 is rotated at a high speed, and the solvent is drained from the laundry. The removed solvent is also collected in the tank 31. Thereafter, the laundry is dried by circulating the air in the drum 5 between the circulation path 8 and the drum 5 while the drum 5 is rotated at a low speed. The vaporized solvent that evaporates from the laundry by drying is also aggregated and recovered. Note that the laundry is efficiently washed and dried by stirring the laundry by the baffle 5b when the drum 5 rotates.

  In the drying step, the blower 10 is rotated by the blower motor 9, and the air in the drum 5 is circulated from the air outlet 7 through the circulation path 8 to the air inlet 6. In the circulation path 8, drying coolers 11 and 12 are provided, and a drying heater 13 (heat exchanger) is provided in the vicinity of the air inlet 6. The air flowing from the drum 5 to the circulation path 8 through the air outlet 7 contains a vaporized solvent (solvent gas). The air containing the solvent gas is cooled by the drying coolers 11 and 12, thereby The solvent gas inside liquefies. That is, the air containing the solvent passing through the circulation path 8 is cooled by the drying coolers 11 and 12 to condense the solvent and recover it from the air. Thereafter, the air is heated by the drying heater 13, and the heated air is supplied from the air inlet 6 into the drum 5 as dry air. In the drum 5, the heated air exchanges heat with the laundry to vaporize the solvent contained in the laundry. The evaporated solvent flows together with air from the air outlet 7 to the circulation path 8. By repeating this cycle, that is, a cycle in which the air in the drum 5 circulates between the drum 5 and the circulation path 8, the laundry in the drum 5 is dried. The dry cleaner 1 is configured to supply the drying air from the air inlet 6 to the laundry in the drum 5 through the outer tub opening 4a and the drum opening 5a. The drum opening 5a is the largest hole in the drum 5, and the drying air can be efficiently supplied to the laundry through the drum opening 5a. Further, since the air in the drum 5 is circulated by the circulation path 8, the air heated by the drying heater 13 and supplied to the drum 5 exchanges heat with the laundry in the drum 5 so that the moisture (solvent of the laundry) After being vaporized, it is reused for drying laundry without being discharged with the vaporized moisture. Therefore, it can be said that this dry cleaner 1 is an environmentally friendly device.

By the way, the solvent is flammable, and if the temperature control of the heated air is not reliably performed in the drying process, the vaporized solvent may ignite or explode.
Therefore, in order to detect the temperature of the heated air supplied from the air inlet 6 to the drum 5, the drum is arranged on the downstream side of the drying heater 13 in the circulation path 8 (downstream side in the air flow direction, the same applies hereinafter). An inlet temperature thermistor 14 and an inlet temperature overheat prevention thermistor 15 are provided. Although not shown, the inlet temperature overheat prevention thermistor 15 is connected to a transistor circuit, for example, for detecting the temperature of 95 ° C. to disconnect the circuit through the transistor. The operating temperature is lower than that of the thermostat. There is an advantage that it can be detected more accurately and the temperature reactivity is good.

  In the circulation path 8, in order to detect the temperature of the air discharged from the air outlet 7, a drum outlet temperature thermistor 16 and a monitor outlet temperature abnormality determination thermistor for determining whether or not the drum outlet temperature thermistor 16 has failed. 17 is provided. Further, in order to detect the air temperature after being cooled by the downstream cooler of the two dry coolers 11 and 12, the circulation path 8 constitutes a part of the cooler temperature thermistor 18 and a safety circuit. A cooler temperature overheat prevention thermistor 19 is provided.

  Further, the circulation path 8 located between the drying cooler 12 and the drying heater 13 is provided with a breathing port 20 and a gate valve V14 for adjusting the pressure when the pressure in the circulation path 8 increases excessively. ing. Normally, the breathing port 20 is open, and the gate valve V14 is open so that air flows through the circulation path 8. Furthermore, an explosion-proof opening 26 is provided for allowing the air containing the solvent gas flowing through the circulation path 8 to ignite and cause an explosion in order to escape the blast. The explosion-proof port 26 is urged in a closing direction by a spring (not shown).

  The drying coolers 11 and 12 are connected to the refrigerator 23 via refrigerant passages 22a, 22b, and 22c. The refrigerator 23 is provided outside the main body 2. When the drying cooler electromagnetic valve 2Y inserted in the refrigerant passage 22a is opened, the refrigerant (for example, cold water) flows from the refrigerator 23 to the drying cooler 12 and the drying cooler 11 through the refrigerant passages 22a and 22b. 12 and the drying cooler 11 perform a cooling operation. Here, although the drying coolers 11 and 12 are connected in series with the refrigerator 23, they may be connected in parallel. Specifically, refrigerant passages 22a and 22c are provided for the drying coolers 11 and 12, respectively, and the refrigerant from the refrigerator 23 is supplied to the drying coolers 11 and 12 individually. Of course, the refrigerator 23 may be provided separately according to the drying coolers 11 and 12.

  The drying heater 13 is a so-called radiator that heats the surroundings by allowing steam to pass through and releasing the heat of the steam from the fins, and is connected to steam paths 24 (steam supply paths) and 25. Specifically, the steam passage 24 connects the steam source outside the apparatus and the drying heater 13. In addition, an inlet valve V20 is inserted in the steam passage 24. In the steam passage 24, a portion between the drying heater 13 and the inlet valve V20 has a relatively large path diameter relative to the first steam supply passage 24a. Branches to the second steam supply path 24b having a narrow path diameter. A first valve V27 is inserted into the first steam supply path 24a, and a second valve V28 is inserted into the second steam supply path 24b. In this embodiment, the path including the steam passage 24 to the drying heater 13 corresponds to the heating means of the present invention. On the other hand, the steam passage 25 is a passage for discharging the steam supplied from the steam passage 24 to the drying heater 13 to the outside of the apparatus.

  By opening the inlet valve V20 and the first valve V27 and / or the second valve V28, steam (for example, steam of 110 to 120 ° C.) is supplied to the drying heater 13, and the drying heater 13 is The heating operation of the air in the circulation path 8 is performed. Since the first steam supply path 24a and the second steam supply path 24b have different steam supply amounts, one or both of the first steam supply path 24a and the second steam supply path 24b are used as necessary. Alternatively, steam may be supplied to the drying heater 13.

  In the drying step, the rotation of the blower motor 9, the inlet valve V20, and the first valve V27 and / or the second valve are usually based on the detected temperatures of the drum inlet temperature thermistor 14, the drum outlet temperature thermistor 16, and the cooler temperature thermistor 18. The opening and closing of the valve V28 is controlled. In the dry cleaner 1, an electric circuit for controlling the opening and closing of the first valve V27 and the second valve V28 is configured as a safety circuit 70 (described later) in order to prevent ignition and explosion of the solvent gas. An electric circuit for controlling the opening and closing of each valve (V27, V28) will be described in detail later.

  The tank / filter kit 3 includes a tank 31 for storing a solvent, and a first filter 32 and a second filter 33 connected in series for filtering the solvent pumped out of the tank 31. One end of a pumping pipe 34 is connected to the lower surface of the tank 31. A valve V <b> 1 is inserted into the pumping pipe 34, and the other end is connected to the junction 35. The junction 35 is connected to the suction side of the solvent pump 36, and the discharge side of the solvent pump 36 is connected to the inlet of the three-way valve V6. One outlet of the three-way valve V6 is connected to one end of the flow pipe 37, and the other end of the flow pipe 37 is connected to the tank 31 via the valve V19. A middle portion of the flow pipe 37 (between the three-way valve V6 and the valve V19) is branched and connected to the series connection of the first filter 32 and the second filter 33. A flow pipe 38 is connected to the outlet side of the second filter 33, and the front end of the flow pipe 38 is connected to an inlet of a solvent heat exchanger 39 provided in the main body 2.

One end of the bypass pipe 40 is connected to the other outlet of the above-described three-way valve V6, and the other end is joined to the flow pipe 38 connected to the inlet of the solvent heat exchanger 39.
Therefore, by switching the outlet of the three-way valve V6, the solvent is supplied to the solvent heat exchanger 39 through the first filter 32 and the second filter 33, or bypassed by the bypass pipe 40 without passing through the filters 32 and 33, The heat exchanger 39 can be switched.

  A vapor pipe 41 and a refrigerant pipe 42 are disposed in the solvent heat exchanger 39. Each of the steam pipe 41 and the refrigerant pipe 42 is a pipe swirled in a coil shape, for example. Steam passages 43 and 44 are connected to the steam pipe 41. The steam passage 43 connects between the steam pipe 41 and the steam passage 24, and a valve V21 is inserted in the middle thereof. On the other hand, the steam passage 44 is a passage for discharging the steam supplied from the steam passage 43 to the steam pipe 41 to the outside of the apparatus. When the valve V21 is opened, steam flows through the steam passage 43 to the steam pipe 41, and the steam is discharged through the steam passage 44. While the solvent passes through the solvent heat exchanger 39, heat exchange is performed between the high-temperature steam pipe 41 and the solvent, and the solvent is heated. On the other hand, refrigerant passages 45a and 45b are connected to the refrigerant pipe 42, and a solvent cooler electromagnetic valve 3Y is inserted into the refrigerant passage 45a. When the solvent cooler electromagnetic valve 3Y is opened, the refrigerant is passed through the refrigerant pipe. While the solvent passes through the solvent heat exchanger 39, heat exchange is performed between the solvent and the refrigerant pipe 42, and the solvent is cooled. By controlling the opening and closing of the valve V21 and the opening and closing of the solenoid valve 3Y for the solvent cooler, the solvent heat exchanger 39 switches between heating and cooling of the solvent, and the temperature of the solvent after passing through the solvent heat exchanger 39 Can be adjusted to a desired temperature.

One end of a circulation pipe 46 is connected to the outlet side of the solvent heat exchanger 39. The other end of the flow pipe 46 is connected to the inlet of the three-way valve V9. The flow pipe 46 is provided with a liquid temperature thermistor 47 for measuring the temperature of the solvent, and a liquid temperature overheat prevention thermistor 48 for preventing the liquid temperature from rising above a predetermined temperature. It has been.
The circulation pipe 46 further includes a soap concentration sensor 50 on the downstream side of the two thermistors.
Is provided.

One end of the liquid supply pipe 51 is connected to one outlet of the three-way valve V9, and the other end is connected to the outer tub 4 so that the solvent can be supplied into the drum 5. One end of a feedback pipe 52 is connected to the other outlet of the three-way valve V <b> 9, and the other end is connected to the tank 31.
In order to recover the solvent condensed by the drying coolers 11 and 12 in the circulation path 8, one end of a recovery pipe 62 is connected below the position where the drying coolers 11 and 12 in the circulation path 8 are arranged. The other end of the recovery pipe 62 is connected to the water separator 63. In the water separator 63, the water contained in the recovered solvent is separated, and the separated water is drained through the drain pipe 64. Then, the solvent is returned to the tank 31 through the recovery pipe 65.

A drainage port 55 is formed in the lowermost part of the outer tub 4, and a liquid level detection container 56 is connected to the drainage port 55. The liquid level detection container 56 is provided with two liquid level switches, a standard liquid level switch 57 and a drain liquid level switch 58. The liquid level detection container 56 also serves as a trap such as a button dropped from the laundry falling from the drainage port 55 during washing.
One end of a recovery pipe 59 is connected to the lower end of the liquid level detection container 56. A valve V4 is inserted into the recovery pipe 59, and the other end of the recovery pipe 59 is connected to the junction 35.

Further, the other end of the soap pipe 61 whose one end is connected to the soap container 60 is joined to the joining point 35. A valve V17 is inserted into the soap pipe 61.
Next, the flow of the solvent in the piping system diagram shown in FIG. 2 will be described.
In the washing process, first, the solvent stored in the tank 31 is supplied to the drum 5 (outer tub 4). Therefore, the valve V1 is opened, the solvent pump 36 is driven, the three-way valve V6 is opened on the flow pipe 37 side, and the valve V19 is closed. As a result, the solvent in the tank 31 flows through the flow pipe 38 through the first filter 31 and the second filter 33, and after the temperature is adjusted by the solvent heat exchanger 39, the three-way valve V9 passes through the flow pipe 46. It flows to. The three-way valve V <b> 9 is open on the liquid supply pipe 51 side, and the solvent is supplied to the outer tank 4 through the liquid supply pipe 51. At the time of supply, the valve V4 is closed. The amount of the solvent accumulated in the outer tub 4 is detected by the standard liquid level switch 57. When a predetermined amount (a quantity suitable for washing) of the solvent is accumulated in the outer tub 4, the valve V9 is switched and the liquid supply pipe 51 is switched. The side is closed and the feedback tube 52 side is opened.

The solvent stored in the tank 31 is mixed with soap in advance, and the soap concentration in the solvent is measured by the soap concentration sensor 50 when the solvent passes through the flow pipe 46. When the soap concentration is low, the valve V17 is opened, and the soap in the soap container 60 is pumped out through the soap pipe 61 and mixed into the supplied solvent.
In addition, when supplying the solvent to the outer tub 4, the three-way valve V 6 is switched in some cases, and the solvent is supplied to the solvent heat exchanger 39 through the bypass pipe 40 without passing through the filters 32 and 33, and to the outer tub 4. You may make it supply.

In the draining and draining process, the valve V4 is opened, the valve V1 is closed, and the solvent pump 36 is driven. The three-way valve V6 is opened on the flow pipe 37 side, the valve V19 is opened, and the solvent is returned to the tank 31.
Alternatively, the valve V19 is closed, and the solvent flowing through the flow pipe 37 passes through the filters 32 and 33, the flow pipe 38, the solvent heat exchanger 39, and the flow pipe 46, and then flows through the feedback pipe 52 via the three-way valve V9. You may make it return to 31. In this way, the solvent after washing discharged from the outer tub 4 and the solvent drained from the laundry by centrifugal force can be purified and returned to the tank 31 by passing through the filters 32 and 33.
<Electrical configuration of dry cleaner 1>
FIG. 3 is a block diagram showing an electrical configuration of the dry cleaner 1 and shows a portion related to the present invention.

The dry cleaner 1 is provided with a control unit 81 (control means) composed of, for example, a microcomputer.
An operation button 66 and a display panel 67 provided on the operation panel 2b are connected to the control unit 81. When the user operates the operation button 66, an input signal corresponding to the operation is controlled. This is input to the unit 81. In addition, an output signal corresponding to the operation status of the dry cleaner 1 is input to the display panel 67, and the operation status is displayed as character information on the display panel 67.

  Further, a three-way valve V9, a valve V4, and a drum motor 21 (drive motor) are connected to the control unit 81 as various control objects, and the operation of these various control objects is controlled by the control unit 81. For example, in the washing process, the three-way valve 9 is opened to the liquid supply pipe 51 side, and the solvent is supplied to the drum 5 (outer tub 4). Further, in the liquid removal step, the valve V4 is opened, and the solvent discharged in the outer tank 4 is returned to the tank 31.

In addition, the first valve V27 and the second valve V28 are connected to the control unit 81 via a safety circuit 70.
The safety circuit 70 is electrically connected to the drum motor 21, the speed detector 68 and the timer 69, the rotational speed of the drum motor 21 is detected by the speed detector 68, and the timer operates in accordance with this, An input signal of the timer is input to the safety circuit 70. In addition, the controller 81 can control the operation of the first valve V27 only after the safety circuit 70 is turned on in response to an input signal from the timer. On the other hand, the second valve V28 can be controlled by the controller 81 even when the safety circuit 70 is in the OFF state. The specific configuration of the safety circuit 70 will be described in detail below with reference to FIG.
<Solvent gas concentration safety system>
FIG. 4 is a diagram showing a relay sequence control circuit 71 constituting the solvent gas concentration safety system. Here, the solvent gas concentration safety system is a system for preventing ignition or explosion of solvent gas during the drying process. In order to construct this system, the dry cleaner 1 includes a relay sequence control. A circuit 71 is provided.

  The relay sequence control circuit 71 is a control circuit for controlling the first valve V27 and the second valve V28. For example, the relay sequence control circuit 71 is connected to a DC power supply (for example, DC 24V), A parallel connection circuit is provided in which the valve V27 and the second valve V28 are connected in parallel. In addition, a first switch 77 and a second switch 78 are provided in series with the first valve V27 and the second valve V28, respectively, and are controlled by a microcomputer in the control unit 81. Each of the valves (V27, V28) is opened by inputting ON signals output by the ON control of the first switch 77 and the second switch 78 to the first valve V27 and the second valve V28, respectively.

Further, a second contact 76 a provided in the second relay 76 is further connected in series to the series connection of the first valve V 27 and the first switch 77. Thereby, in the state where the second contact 76a is not ON, the safety circuit 70 is configured such that the first valve V27 is kept in an inoperable state regardless of the control of the control unit 81 turning on the first switch 77. ing.
The relay sequence control circuit 71 is provided with a detection circuit 79 for controlling the second contact 76a.

The detection circuit 79 is connected in parallel to the safety circuit 70, and is connected in series with the second relay 76 and the first contact 75a provided in the first relay 75, and connected in parallel with this series connection. 1 relay 75 and a timer contact 69 a provided in the timer 69 are connected in series.
The first relay 75 and the second relay 76 are devices having a function of opening and closing contacts by electromagnetic force, such as electromagnetic relays, and are provided with electromagnetic coils (not shown) provided in these relays (75, 76). ) Is closed, each contact (75a, 76a) is closed.

Further, a door switch 74 for detecting the state of a door (not shown) that opens and closes the outer tub opening 4a is connected in series to the first relay 75 and the second relay 76, and the door switch 74 is turned ON while the door is closed.
The timer 69 is connected in parallel to the door switch 74 and the first relay 75 (the door switch 74 and the second relay 76). For example, when the timer 69 starts measuring time by inputting a signal and a predetermined time has elapsed, The timer contact 69a provided in is configured to be turned on. The timer 69 is connected in series with the detection switch 73, and when the detection switch 73 is turned ON, an input signal for starting time measurement is given to the timer 69.

  The detection switch 73 is included in an internal circuit (not shown) of the speed detector 68 connected to the drum motor 21 (see FIG. 3). The drum motor 21 has an inverter circuit whose frequency is controlled, for example, and the speed detector 68 is connected to the inverter circuit. The speed detector 68 is configured to detect a frequency output when the drum motor 21 is equal to or higher than a predetermined rotation speed, and to turn on the detection switch 73 during the rotation speed or higher.

Next, the control flow of the relay sequence control circuit 70 will be described.
When the washing process is completed and the liquid removal process is started, the drum 5 is rotated at a high speed by the rotational power of the drum motor 21 and the solvent contained in the laundry is discharged. When the rotational speed of the drum motor 21 is, for example, 500 rpm or higher, the frequency output when the rotational speed is 500 rpm or higher is detected by the speed detector 68, and the detection switch 73 is turned on.

  When the detection switch 73 is turned on, the ON signal is input to the timer 69 and the timer 69 starts measuring time. Thereafter, when the time for which the detection switch 73 is ON, that is, the time for which the drum motor 21 is rotating at 500 rpm or more, for example, 4 minutes elapses, the timer contact 69a is turned ON. In the washing process and the draining process, the door (not shown) for opening and closing the outer tub opening 4a is closed, so that the door switch 74 is kept in the ON state.

  When the timer contact 69a is turned on, a current flows through the electromagnetic coil inside the first relay 75, and the first contact 75a is turned on. When the first contact 75a is turned on, a current flows through the electromagnetic coil inside the second relay 76, and the second contact 76a is turned on. Thereby, since the control part 81 carries out ON control of the 1st switch 77, the (+) side and (-) side of the 1st valve V27 will be in a conduction | electrical_connection state, Therefore The 1st valve V27 can be opened.

  Thus, in a state where the speed detector 68 detects that the rotational speed of the drum motor 21 is 500 rpm or more and the timer 69 does not measure that the drum 5 has been rotated at that rotational speed for 4 minutes, Since the contact point 76a is in the OFF state, even if the control unit 81 turns the first switch 77 on, the ON signal is not transmitted to the first valve V27, and the first valve V27 is kept in an inoperable state. That is, the control unit 81 can turn on the first valve V27 only after the laundry is drained for 4 minutes at a drum rotation speed of 500 rpm or more.

  As a result, in the drying process, for example, the microcomputer (microcomputer) of the control unit 81 runs away and steam is continuously supplied to the drying heater 13, so that even if the laundry is exposed to hot hot air, it is included in the laundry. Since a certain amount of the solvent to be removed is removed in the liquid removal step, the solvent gas concentration does not exceed the lower flammability limit concentration (for example, 0.8 vol%). As a result, safety in the drying process is reliably ensured, and a safer dry cleaner that does not cause danger such as ignition can be obtained. Further, since such control can be performed only by the operation of the detection switch 73 and the timer 69, the control is also simple.

  Further, the second valve V28 has a smaller steam supply amount than the first valve V27, and even if steam is continuously supplied to the drying heater 13, the temperature of the drying heater 13 does not increase so much. For this reason, there is no possibility that the solvent gas concentration will rise to a concentration exceeding the lower limit of flammability, so there is no need to control by the safety circuit 70. As a result, there is no need to incorporate extra relays or the like in the circuit, thus saving costs.

The present invention is not limited to the embodiment described above, and various modifications can be made within the scope of the claims.
For example, in the above-described embodiment, the condition that the first valve V27 can be “opened” is “the laundry is drained for 4 minutes at a drum rotation speed of 500 rpm or more”, but this condition is only a guideline. Yes, as long as the solvent gas concentration does not exceed the lower flammability limit concentration, it is not limited to this condition, and further liquid removal treatment may be performed.

  In the above-described embodiment, the first valve V27 closing / opening control is shown as an example. However, the inlet valve V20 provided in the steam passage 24 that is the supply source of the steam to the first valve V27 is controlled to open / close. Also good.

It is a front side perspective view about the principal part of the dry cleaner concerning one embodiment of this invention. It is a piping system diagram of the dry cleaner shown in FIG. It is a block diagram which shows the electric constitution of the dry cleaner shown in FIG. 1, Comprising: The part relevant to this invention is shown. It is a figure which shows the relay sequence control circuit which comprises a solvent gas concentration safety system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dry cleaner 4 Outer tank 5 Drum 8 Circulation path 13 Drying heater 21 Drum motor 24 Steam path 24a 1st steam supply path 24b 2nd steam supply path 68 Speed detector 69 Timer 69a Timer contact 70 Safety circuit 73 Detection switch 75 1st Relay 75a First contact 76 Second relay 76a Second contact 77 First switch 78 Second switch 81 Control unit V20 Inlet valve V27 First valve V28 Second valve

Claims (6)

A dry cleaner for washing, draining and drying laundry using a flammable solvent,
A treatment tank for storing the laundry and washing, draining and drying;
A circulation air passage for taking out the air in the treatment tank and circulating the closed flow path for drying and returning it to the treatment tank;
Heating means for heating the air flowing through the circulation air passage;
Control means for controlling the operation of the heating means to execute a drying step;
In the processing tank, a signal output means for outputting an end signal in response to completion of a predetermined liquid removal process,
A dry cleaner comprising: a safety circuit that keeps the heating means in an inoperable state regardless of the control of the control means when the end signal is not output. The treatment tank includes a liquid-tight outer tank,
An inner tub that is rotatably provided in the outer tub and rotates to remove the solvent contained in the laundry contained therein by centrifugal force;
A drive motor for rotating the inner tub,
The signal output means includes a mechanism for outputting the end signal when the inner tank or the drive motor rotates at a predetermined rotational speed or more and the rotation has passed for a predetermined time. The stated dry cleaner. The signal output means is a switch that is turned on when the rotational speed of the inner tank or the drive motor is equal to or higher than a predetermined rotational speed;
The timer according to claim 2, further comprising: a timer that starts timing when the switch is turned on, measures a time during which the switch is turned on, and outputs the end signal when the switch is measured for a predetermined time. Dry cleaner. The heating means includes a heat exchanger for exchanging heat with the air flowing through the circulation air passage;
Steam supply means for supplying steam to the heat exchanger,
4. The safety circuit according to claim 1, wherein steam is not supplied from the steam supply means to the heat exchanger in order to keep the heating means in an inoperable state. Dry cleaner. The steam supply means includes a steam supply path for supplying steam;
A valve for closing and opening the steam supply path,
5. The dry cleaner according to claim 4, wherein the safety circuit always closes the valve to keep the heating means in an inoperable state. A plurality of the steam supply passages are provided, and a valve is interposed in each steam supply passage,
6. The dry cleaner according to claim 5, wherein the safety circuit is normally closed only to a predetermined valve in order to keep the heating means in an inoperable state.

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