JPH0688678A - Drying heater - Google Patents

Abstract

PURPOSE:To provide a drying heater in which a safety device for preventing an overheating operation is positively operated. CONSTITUTION:A drying heater 100 disposed within a chamber 4G at a drying part 20 is constructed such that a heating member 106, a temperature fuse 108 and a thermostat 110 are integrally stored within a thermal radiating part 104 formed by a barrel 112 and fins 114. As a power source is supplied to this heating member, the thermal radiating part is overheated and air passing within the chamber 46 is overheated to produce dried air. The temperature fuse and the thermostat are operated such that the supplying of power source to the heating member is interrupted when they are overheated by the heating member. Temperature of the drying heater is accurately measured by a temperature sensor 102 arranged at a downstream side of air passing through the drying heater.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying heater for heating air supplied from a blowing means provided in a light-sensitive material drying device to generate dry air for drying a light-sensitive material.

[0002]

2. Description of the Related Art Photosensitive materials such as photographic papers and films treated with a processing solution are dried and finished. As a photosensitive material drying device for drying the photosensitive material, a device for drying with a warm air is generally used.

The apparatus for drying the photosensitive material with warm air is provided with an air blowing means such as a blower, a chamber, a duct, and an outlet pipe. The blowing pipe is arranged in the vicinity of the conveyance path of the photosensitive material in the drying chamber, and has slits for uniformly ejecting warm air along the width direction of the photosensitive material. The blowout pipe is connected to a duct, and the wind generated by the blower is supplied through the chamber and the duct. As a result, this wind is ejected from the slit of the blowing pipe toward the surface of the photosensitive material.

A heater for heating the air sent from the blower is arranged in the chamber. When the air from the blower passes near the heater, the air is heated to a desired temperature by the heater. , Is supplied to the blowing pipe as hot air for heating the photosensitive material and is discharged toward the surface of the photosensitive material. This warm air heats and dries the photosensitive material conveyed in the drying chamber.

Such a heater measures the temperature of hot air and controls the heater by turning it on and off so that the temperature is within a predetermined range. In addition, a temperature fuse, as a safety mechanism to prevent overheating, is placed at a position separate from the heater.
A thermostat etc. is provided. The thermostat shuts off the supply of power to the heater when the temperature exceeds a certain temperature in order to prevent the heater from overheating when the temperature controller operates abnormally in normal use. The thermal fuse mechanically shuts off the power supply to the heater when the thermostat malfunctions. In the drying section, it is preferable to prevent overheating by such a double safety mechanism.

[0006]

However, since the heater is used in a state where a heating element such as a nichrome wire is exposed, a safety device such as a thermal fuse or a thermostat is arranged at a predetermined distance from the heater. Must. For this reason, since the heater is separated from the thermal fuse, the thermostat, etc., the heater may not operate quickly and accurately even if it overheats abnormally.

Further, a temperature sensor for controlling the heating temperature of the heater must be provided separately from the heater,
It was difficult to accurately measure the drying temperature.

The present invention has been made in consideration of the above facts, and provides a drying heater in which a safety device can be reliably operated to prevent overheating, and at the same time, a drying heater capable of performing accurate temperature control. It is intended to provide a heater.

[0009]

A drying heater according to claim 1 of the present invention is arranged adjacent to a heating element and supplies power to the heating element when the heating element exceeds a first predetermined temperature. And a first protection unit that shuts off the heat source and enables the power source to be supplied when the temperature of the heating element becomes equal to or lower than the first predetermined temperature, and the heating element disposed adjacent to the heating element is the first heating element. Second protection means for shutting off the power supply to the heating element when a second predetermined temperature higher than the predetermined temperature is exceeded, and the first protection means and the second protection element together with the heating element. And a heat radiating portion for heating the air supplied by the blower means by the heat of the heat generating body when the air supplied by the blower means passes through the surroundings.

A drying heater according to claim 2 of the present invention comprises:
The drying heater according to claim 1, wherein a temperature detecting means for controlling a heat generation temperature of the heat generating element within a predetermined range is arranged on a downstream side of a flow of air passing through the heat radiating portion.

[0011]

In the drying heater according to the first aspect of the present invention, the first protection means and the second protection means are housed in the heat radiation portion integrally with the heating element. The heat of the heating element is transferred to the heat radiating section, which raises the temperature of the heat radiating section, and the heat radiating section transfers this heat to the air supplied from the blowing means. In this drying heater, since the first and second protection means are integrally housed in the vicinity of the heating element in the heat radiation section, the heat of the heating element is quickly and reliably transmitted to these protection means. Therefore, it is possible to prevent any overheating of the heating element by operating any one of the first and second protection means reliably.

The operating temperature of the second protecting means may be set higher than the operating temperature of the first protecting means, and a thermostat or the like can be applied as the first protecting means, or the second protecting means. As such, a thermal fuse or the like can be applied. It is preferable that the second protection means can eliminate the cause of the abnormal temperature rise of the heating element and restore the supply of power to the heater when the temperature of the heating element falls within a predetermined range.

The heat radiating portion preferably transfers the heat from the heat generating element to the surrounding air efficiently. For example, one having a large number of fins for heat radiation formed on the outer periphery of a substantially cylindrical housing member is applied. it can. The heat of the heating element is transmitted to the fins, and the heat is radiated from the fins to efficiently heat the surrounding air, and the air from the air blowing means can be sent as warm air (including heated dry air) to the blowout pipe or the like. .

In the drying heater according to the second aspect of the present invention, the temperature detecting means of the controller for controlling the operation of the heating element is provided on the downstream side of the air flow passing through the heat radiating portion. Therefore, it is possible to accurately control the operation of the heating element by measuring the temperature of the air heated by the heat radiating section with this temperature detecting means.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an automatic developing apparatus 10 which is a photosensitive material processing apparatus applied to this embodiment. The automatic developing device 10 is provided with a processing liquid processing section 11 and a drying section 20 in a machine frame 12. The processing liquid processing section 11 includes a developing tank 14, a fixing tank 16 and a washing tank 18 which are partitioned by a partition wall 13 along the transport direction of the film F which is a photosensitive material.

Insertion port 1 for film F of automatic developing device 10
An insertion rack 17 for drawing the film F into the automatic developing device 10 is arranged near the position 5. Also, the insertion slot 1
An insertion detection sensor 80 for detecting the film F to be inserted is provided in the vicinity of 5. Further, an insertion stand for manually inserting the film F or an auto feeder or the like for automatically inserting the film F by the conveying means can be attached to the insertion opening 15 of the automatic developing device 10.

A developer is stored in the developing tank 14, and a transport rack 24 having a transport roller 22 for transporting the film F driven by a motor (not shown) is provided so as to be immersed in the developer. In the fixing tank 16, a fixing liquid is stored, and a transport rack 28 having a transport roller 26 that drives the film F by being driven by a motor (not shown) is soaked in the fixing liquid. Further, washing water is stored in the washing tank 18, and a transport rack 32 having a transport roller 30 that drives the film F by being driven by a motor (not shown) is disposed so as to be immersed in the washing water.

Two heat exchangers 19 are arranged below the processing liquid processing section 11, and the developing solution in the developing tank 14 and the fixing solution in the fixing tank 16 are respectively transferred to the heat exchanger 19. After being sent, heat exchange is performed there and the liquid temperature is adjusted to a predetermined value, and then the liquid is sent back to the developing tank 14 and the fixing tank 16. As a result, the liquid temperatures of the developing solution in the developing tank 14 and the fixing solution in the fixing tank 16 are maintained within a predetermined range.

Between the developing tank 14 and the fixing tank 16 and the fixing tank 1
A crossover rack 34 is disposed on the upper portion between the 6 and the washing tank 18. The crossover rack 34 holds the nipping / conveying rollers 3 for conveying the film F from the tank on the upstream side in the conveying direction of the film F to the tank on the downstream side.
6 and a guide 38 for guiding the film F.

Therefore, the automatic developing device 10 is inserted from the insertion port 15.
The film F fed into the inside is inserted into the developing tank 14 by the insertion rack 17 and is conveyed in the developing solution by the conveying roller 22 to be developed. The developed film F is sent to the fixing tank 16 by the crossover rack 34, where it is carried in the fixer by the carrying roller 26 and fixed. The fixed film F is sent to the washing tank 18 by the crossover rack 34, where it is conveyed in washing water by the conveying roller 30 and washed. In this way, the film F
Is treated with a treatment liquid.

A drainage pipe (not shown) is provided at the bottom of each of the developing bath 14, the fixing bath 16 and the water washing bath 18, and a drainage valve 21 is attached to each of these drainage pipes. Therefore, if necessary, these drain valves 21
Is opened, the developing solution, the fixing solution and the washing water in the developing tank 14, the fixing tank 16 and the washing tank 18 can be discharged. Further, the developing tank 14, the fixing tank 16 and the washing tank 18
In accordance with the processing of the film F, the processing liquid (water to the washing tank 18) is replenished by a replenishing liquid replenishing mechanism (not shown). The excess processing liquid in the developing tank 14, the fixing tank 16 and the water washing tank 18 by replenishing the processing liquid is discharged to a waste liquid tank by an overflow pipe (not shown). The replenishment of water to the washing tank 18 is performed by a pipe provided from the tap to the water supply tank 54 in response to the detection of the film F by the insertion detection sensor 80 provided near the insertion opening 15 of the film F of the automatic developing device 10. It is performed by opening and closing a solenoid valve 92 arranged in the middle of 90. The developing tank 14 and the fixing tank 16 are provided with a floating lid which covers the surface of each processing liquid and has an opening through which the film F to be conveyed can be inserted to suppress evaporation of the processing liquid and oxidation fatigue. It is preferable.

A squeeze rack 40 is arranged between the washing tank 18 and the drying section 20. This squeeze rack 4
Reference numeral 0 has a transport roller 42 that transports the film F, which is sent out from the wash tank 18 and has wash water adhered thereto, to the drying unit 20 while squeezing it, and a guide 43 that guides the film F.

The drying section 20 includes a transport roller 44 for transporting the film F and a blower fan 4 for generating dry air.
5, a chamber 46 having a built-in heater for heating the air from the blower fan 45 to produce dry air, and a blowing pipe 47 for ejecting the dry air toward the film F and the transport roller 44. Further, the film F is conveyed obliquely upward in the drying turn portion 48 on the downstream side of the conveying roller 44 in the conveying path. Furthermore, in the automatic developing device 10,
A receiving box 49 is provided adjacent to the drying section 20 so as to accommodate the film F sent from the drying turn section 48.

Accordingly, the film F squeezed by the squeeze rack 40 is heated and dried by the drying air blown from the blowing pipe 47 while being heated and conveyed by the conveying roller 44 warmed by the drying air in the drying section 20. It
After that, the film F is turned by the drying turn section 48, discharged into the receiving box 49, and accommodated therein.

Here, the mechanism for generating the drying air for heating and drying the film F, which is blown from the blowing pipe 47 toward the film F, will be described in detail with reference to FIGS. 2 to 5.

The blower fan 45 is adapted to take in air inside the drying chamber or air outside the machine and supply it into the chamber 46. As shown in FIG. 2, the drying heater 100 to which the present invention is applied is provided in the chamber 46.
Further, a temperature sensor 102, which is a temperature detecting means for detecting the temperature of the dry air, is provided.

As shown in FIGS. 3 and 4, the drying heater 100 includes a heat radiating portion 104, a heating element 106 housed in the heat radiating portion 104, a thermostat 110 as a first protection means, and a second heating element. Thermal fuse 1 which is a protection means
08. The heat radiating portion 104 has a large number of fins 114 integrally formed on the outer peripheral portion of a substantially cylindrical tubular body 112 of which one end is closed and which is closed at one end to project radially outward. One is provided. The drying heater 100 is arranged such that the longitudinal direction thereof is orthogonal to the flow of air from the blower fan 45, and the fins 114 are provided.
Air flows between them. The fins 114 are provided in the drying heater 100 in order to efficiently heat the air by increasing the area in contact with the air having a fast flow.

As shown in FIG. 4, the heater 10 for drying is used.
A heat transfer member 116 is filled inside the cylindrical body 112 of 0, and the thermostat 110, the heating element 106, and the thermal fuse 108 are connected in series and housed therein. As the heat transfer member 116, it is preferable to use MgO (magnesium oxide), silicon compound, or the like, but it is also possible to use air as the heat transfer member 116.

The heating element 106 is adapted to generate heat when supplied with power and heat the fin 114 together with the tubular body 112 via the heat transfer member 116.

The contact of the thermostat 110 is normally closed so that power can be supplied to the heating element 106. However, when the thermostat 110 is heated to a predetermined temperature, the contact is opened to cut off the supply of power to the heating element 106. It is like this. In the present embodiment, the temperature at which the thermostat 110 opens the contact is set to 120 ° C. Therefore, when the heating element 106 reaches 120 ° C. or higher, the contact is opened, and when the temperature is 120 ° C. or lower for a predetermined time, the contact is closed again to automatically recover. Incidentally. The thermostat 110 may be automatically reset when the temperature becomes low for a certain period of time, or may be a manual reset type.

In the case of the thermal fuse 108, the thermostat 110 should fail and the heating element 106 continues to be energized.
When the temperature of the heating element 106 is overheated to a predetermined temperature, an internal fuse (not shown) is blown to cut off the supply of power to the heating element 106. This thermal fuse 1
When 08 operates, the thermal fuse 108 or the drying heater 100 must be replaced without automatic recovery. In the present embodiment, this fusing temperature is set to a temperature higher than the operating temperature of the thermostat 110 (about 160 ° C).

The drying heater 100 generates heat when power is supplied to the heating element 106, and the cylindrical body 112 and the fins 114.
Is heated. In addition, the blower fan 4 is placed in the chamber 46.
When the air is supplied from 5, the air is supplied to the drying heater 1
00 to flow to the duct 90. At this time,
The air is heated as it passes near the fins 114 and the cylinder 112. Further, the cylindrical body 112 and the fin 1
The temperature of 14 will be lowered by the passing air.

A temperature sensor 102 is mounted on the downstream side of the flow of air (the flow in the direction of arrow A in FIGS. 2 to 4) passing near the drying heater 100. As shown in FIG. 5, the temperature sensor 102 is connected to a controller 118 provided in a control unit (not shown) of the automatic developing device 10 by a wiring 122. A wiring 120 drawn from the drying heater 100 is connected to the controller 118, and power is supplied to the drying heater 100 via the controller 118. A blower fan 45 is also connected to the controller 118.

The controller 118 is used for the automatic developing device 10.
At the start-up, the drying heater 100 is heated to a set temperature, and the blower fan 45 is operated to generate heated dry air, and the dry air is supplied to the blowing pipe 47. Further, after the start-up, the temperature sensor 102 detects the temperature of the dry air (the temperature of the drying heater 100), and the power supply to the heating element 106 is turned on so that the temperature of the dry air falls within the set range. It is supposed to turn off. In this embodiment, as an example, the temperature of the air passing through the drying heater 100 is 50 ° C.
It is set to be (± 3 ° C).

The air passing through the vicinity of the drying heater 100 is blown as a dry air through the duct 90 into the blow pipe 4.
7 is supplied. As a result, the film F is discharged from the blowing pipe 47 toward the surface of the film F conveyed in the drying section 20, and the film F is heated and dried. The duct 90 has a shape capable of uniformly supplying the dry air to each of the blow pipes 47.
The structure is such that the dry air can be uniformly discharged along the width direction of the film 14.

The operation of this embodiment will be described below. First, the processing of the film F in the automatic processor 10 will be described.

The film F inserted into the automatic developing device 10 through the insertion port 15 is developed with the developing solution in the developing tank 14 and the fixing tank 16.
After the development and fixing process with the fixing solution, the solution is washed with water in the water washing tank 18 to wash away the processing solution. The film F that has been washed with water is sent to the drying unit 20 while the surface moisture is squeezed by the squeeze rack 40. In the drying unit 20, the film F is dried by the heated dry air and the heated transport roller 44, and discharged from the drying turn unit 48 into the receiving box 49. In this way, the films F sequentially inserted into the automatic developing device 10 are subjected to the development processing, and the receiving box 49
Will be housed sequentially.

Here, the temperature of the developer and the fixer stored in the developer tank 14 and the fixing tank 16 is such that the temperature of the liquid inside the tank is the heat exchanger 1.
9 has a predetermined temperature (50 ° C. to 55 ° in this embodiment).
It is heated and kept in C). This temperature is
The film F can be used in a short time in each stable state of the fixer.
The temperature is such that a predetermined optimum sensitivity can be given to.

During the processing of this film F, the heater for drying 1
If a failure occurs in the controller 118 that controls 00, and the power is continuously supplied to the heating element 106, the temperature of the drying heater 100 may gradually rise. At this time, the temperature of the heating element 106 rises, so that the heating element 10
Along with 6, the temperature of the thermostat 110 and the temperature fuse 108 housed in the cylindrical body 112 also rises.

The thermostat 110 opens the contact to shut off the power supply to the heating element 106 when the heating temperature of the heating element 106 reaches the operating temperature (120 ° C. in this embodiment). This stops the heat generation of the heating element 106,
The temperature of the drying heater 100 can be gradually lowered. After that, when the temperature of the drying heater 100 drops to a predetermined temperature, power can be supplied to the heating element 106 again.

Here, if the thermostat 110 should not operate due to a failure, the heating element 106 continues to overheat, but the temperature of this heating element 106 is transmitted to the thermal fuse 108, and the thermal fuse 108 operates. When the temperature (160 ° C. in this embodiment) is reached, the internal fuse is blown and the power supply to the heating element 106 is cut off.

As described above, the drying heater 100 to which the present invention is applied includes the thermostat 110 and the thermal fuse 1.
Since the double overheat prevention function by 08 is provided, even if a failure occurs in the controller 118, it is possible to reliably prevent the device from being damaged due to overheating of the heating element 108.
Further, since the thermostat 110 and the thermal fuse 108 are integrated in the immediate vicinity of the heating element 106, when the heating element 106 has an abnormal temperature rise, it can be detected quickly and reliably.

When power is supplied to the heating element 106 while the blower fan 45 is not operating, the temperature of the heating element 106 rises due to the delay of heat radiation from the drying heater 100, but the heating temperature of the heating element 106 is the thermostat 110. When the operating temperature (120 ° C. in this embodiment) is reached, the contact of the thermostat 110 is opened to shut off the power supply to the heating element 106. In the unlikely event that the thermostat 110 fails and does not operate, the heating element 106 continues to overheat and the thermal fuse 108 keeps its operating temperature (16 in this embodiment).
When it reaches 0 ° C.), the internal fuse is blown and the power supply to the heating element 106 is cut off.

As described above, the drying heater 100 to which the present invention is applied has the same effect as in the case of the failure of the controller 118 as described above, and reliably prevents damage to the device due to overheating of the heating element 106. be able to. Since the temperature sensor 102 is in contact with the drying heater 100,
The controller 118 surely detects this temperature rise,
Power supply to the heating element 106 can be cut off. Therefore, the temperature of the drying heater 100 does not exceed the temperature set by the controller 118. Further, since the temperature sensor 102 can accurately detect the temperature of the drying heater 100, the controller 118
Thus, the temperature of the drying heater 100 can be accurately maintained at the set temperature.

The controller 118 may be so controlled as to confirm the operation of the blower fan 45 of the drying section 20, the drying heater 100, and the temperature sensor 102 when the automatic developing device 10 is started up. For example, when the automatic developing device 10 is started up, the heating element 106 is gradually caused to generate heat, or the temperature rise rate of the drying heater 100 is measured to check the operation of the blower fan 45 and the drying heater 100. Alternatively, the temperature of the dry air in the chamber 46 may be measured, and the detection result of the temperature sensor 102 may be compared to check the operating state of the drying unit 20. If each component is operating normally, You may make it shift to normal operation.

Incidentally, the drying heater 1 applied to this embodiment.
00 does not limit the structure of the drying heater of the present invention. The heat radiating section to which the present invention is applied is only required to house the heating element and the first and second protection means integrally, and to generate a dry air that is efficiently overheated by the heat from the heating element. In this embodiment, each of the set temperature of the drying heater 100, the operating temperature of the thermostat 110, and the fusing temperature of the thermal fuse 108 is shown as an example, and other suitable temperatures may be used. The operation of the drying heater to which the invention is applied is not limited.

Further, in the present embodiment, the present invention is applied to the film F.
However, these do not limit the application of the present invention. INDUSTRIAL APPLICABILITY The present invention can be applied to a drying heater for generating a dry air heated by a photosensitive material processing apparatus that processes other photosensitive materials such as photographic paper.

[0048]

As described above, in the drying heater according to the present invention, since the heating element and the first and second protection means are integrally incorporated, it is possible to reliably detect the temperature rise of the heating element. You can Moreover, since the protection means has a double structure, overheating is prevented quickly and surely.

Further, a temperature detecting means for controlling the operation can be brought into contact with the drying heater. Therefore, the temperature of the drying heater can be reliably detected, and the drying temperature can be accurately controlled, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an automatic developing device applied to this embodiment.

FIG. 2 is a schematic diagram showing a flow of drying air in a drying unit.

FIG. 3 is a main part perspective view showing a drying heater applied to this embodiment.

FIG. 4 is a cross-sectional view of a main part of a drying heater.

FIG. 5 is a configuration diagram of a drying heater including a controller.

[Explanation of symbols]

 10 Automatic Developing Device 20 Drying Part 45 Blower Fan 46 Chamber 100 Drying Heater 102 Temperature Sensor (Temperature Detecting Unit) 104 Radiating Unit 106 Heating Element 108 Thermal Fuse (Second Protecting Means) 110 Thermostat (First Protecting Means) 118 controller

Claims (2)

[Claims] 1. A power supply to the heating element is arranged so as to be adjacent to the heating element and when the heating element exceeds a first predetermined temperature, the power supply to the heating element is cut off and the heating element becomes equal to or lower than the first predetermined temperature. A first protection means capable of supplying the electric power when the heating element is turned on, and the second heating element which is arranged adjacent to the heating element when the heating element exceeds a second predetermined temperature higher than the first predetermined temperature. The second protection means for shutting off the power supply to the heating element and the heating element together with the first protection means and the second protection means are integrally housed, and the air supplied by the blower means surrounds the surroundings. And a heat radiating portion for heating by the heat of the heating element when passing through. 2. The drying heater according to claim 1, wherein temperature detecting means for controlling the heat generation temperature of the heat generating element within a predetermined range is arranged downstream of the flow of air passing through the heat radiating portion. .