This patent application is based on and claims priority pursuant to 35 U.S.C. § 119(a) to Japanese Patent Application No. 2022-090935, filed on Jun. 3, 2022, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.
Embodiments of the present disclosure relate to a supporting structure for a temperature sensor and to a drying device.
In order to increase the durability of ink fixation, there are some cases in which a box-shaped drying device is arranged between an image forming apparatus in which images are printed on a roll sheet and a device such as a winding device and a chiller device that performs post-processing on the printed roll sheet. Such a drying device has a front panel and a rear panel, and multiple heating roller units are arranged between the pair of side panels.
A recording medium such as a continuous sheet that is coated with ink or the treatment liquid is looped around multiple heating rollers of a heating roller unit such that the recording medium is dried.
Some of the multiple heating rollers has an integrated heat source such as a halogen lamp, and the temperature of such an integrated heat source is controlled using a temperature sensor such as a thermopile.
Embodiments of the present disclosure described herein provide a supporting structure for a temperature sensor, and a drying device provided with the supporting structure. The supporting structure includes a front panel, a rear panel, a first supporting member having both ends in a longer-side direction of the first supporting member, and a second supporting member attachable to and detachable from the first supporting member. In the supporting structure, both ends of the first supporting member are removably supported by the front panel and the rear panel. In the supporting structure, the temperature sensor is disposed on the second supporting member, and the temperature sensor detects surface temperature of a heating roller disposed between the front panel and the rear panel.
A more complete appreciation of embodiments and the many attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.
The accompanying drawings are intended to depict embodiments of the present disclosure and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “includes” and/or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
In describing example embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the present disclosure is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that have the same structure, operate in a similar manner, and achieve a similar result.
Drying Device
A drying device 200 according to an embodiment of the present disclosure and the supporting structure of a thermopile 430 according to an embodiment of the present disclosure that serves as a temperature sensor to detect the temperature of a heating roller 310 of the drying device 200 are described below with reference to the accompanying drawings.
The image forming apparatus 100 according to the present embodiment is an inkjet recording apparatus, and provided with five inkjet heads each of which serves as an ink-droplet discharger. In other words, the image forming apparatus 100 according to the present embodiment is provided with five inkjet heads of colors including black (K), cyan (C), magenta (M), yellow (Y), and special color E from an upstream portion to a downstream portion of the apparatus in the sheet conveyance direction.
The special color E is, for example, orange color. The types and number of colors are not limited to the above.
The image forming apparatus 100 ejects ink from five inkjet heads onto a continuous sheet P that serves as a recording medium. As a result, an image is formed on the continuous sheet P.
The continuous sheet P according to the present embodiment is a belt-like sheet. The material of the continuous sheet P is, for example, a sheet of paper, an overhead projector (OHP) sheet, threads, fibers, leather, metal, plastic, or vinyl, and the continuous sheet P may be all sorts of medium on which ink or some sort of liquid is adhered to form an image.
As a matter of course, the embodiments of the present disclosure can be applied to the drying device of a printer that uses a sheet material such as a cut sheet instead of the continuous sheet P. The continuous sheet P to which ink or some sort of liquid has been applied by the image forming apparatus 100 passes through the drying device 200, and then is sent to a chiller device or a winding device at a downstream portion of the entire apparatus.
As illustrated in
The temperatures of the multiple heating roller units 300 and the heating drum 350 are detected by the multiple thermopile units 400, and the temperatures of the heating drum 350 and a plurality of heating rollers 310 of the multiple heating roller units 300 are controlled by a controller.
In the present embodiment, the continuous sheet P is spirally guided to the heating drum 350 at the center of the apparatus by the multiple conveying rollers 220 and the multiple heating roller units 300. Then, the continuous sheet P that has passed through the heating drum 350 is spirally guided in the reverse direction by the multiple conveying rollers 220 and the multiple heating roller units 300. In this manner, the continuous sheet P is brought in contact with the multiple heating rollers 310 of the multiple heating roller units 300 from two varying directions of the liquid-applied surface and the reverse side. As a result, the continuous sheet P is evenly heated and dried.
Heating Roller Unit and Thermopile Unit
The heating roller unit 300 and thermopile unit 400 according to the present embodiment are described below with reference to
As illustrated in
In other words, both ends of the heating roller unit 300 and thermopile unit 400 in the longer-side direction are supported by the front panel 210F and the rear panel 210R. A rectangular opening 250 is formed in the front panel 210F to allow thermopile unit 400 to loaded or unloaded in the longer-side direction.
The heating roller unit 300 according to the present embodiment includes a heating roller 310 and a heater lamp 320 arranged inside the heating roller 310. In the present embodiment, a set of four heater lamps 320 is arranged. As will be described later in detail with reference to
The continuous sheet P is conveyed in the direction indicated by arrow by means for conveying the continuous sheet P located upstream and downstream from each one of the multiple conveying rollers 220. During the conveyance of the continuous sheet P, each one of the multiple heating rollers 310 is heated by the multiple heater lamps 320 while the heating roller is rotating. Due to such a configuration, the continuous sheet P that is conveyed in contact with the multiple heating rollers 310 is continuously heated and dried.
The thermopile unit 400 according to the present embodiment includes a first supporting member 410 and a second supporting member 420. The second supporting member 420 is provided with a thermopile 430. The lengths of the first supporting member 410 and the second supporting member 420 are approximately equivalent to the distance between the front panel 210F and the rear panel 210R.
As illustrated in
The second supporting member 420 can be mounted on the first supporting member 410 in a detachable manner. As illustrated in
As illustrated in
The first supporting member 410 according to the present embodiment has a pair of rising portions 410a that vertically rise at both ends in the shorter-side direction, and this pair of rising portions 410a guide and align the second supporting member 420 in the shorter-side direction.
As illustrated in
Front and Rear Positioning
As illustrated in
The position of the thermopile 430 when implemented can be prevented from being displaced by those pins including the pair of positioning pins 221, the pair of positioning pins 222, and the pair of positioning pins 280. As illustrated in
As illustrated in
In other words, as illustrated in
The bent piece 410b of the first supporting member 410 is fixed to the front panel 210F as a screw 292 is screwed into a screw hole 261 (see
The pair of right and left positioning pins 221 and 222 are arranged on the rear panel 210R. As illustrated in
Introduction of Cooling Air
As illustrated in
The bracket 420c according to the present embodiment is covered with a cover 440 together with thermopile 430. The cooling air that is flown into the cover 440 through the air duct 240 flows from the rear to the front of the cover 440.
The cover 440 is formed with a through hole 440a through which the outer circumferential surface of the heating roller 310 can be seen through from the thermopile 430 (see, for example,
As illustrated in
Both the pair of flow-rate adjusting orifices 450 may be arranged upstream from the front and rear thermopiles 430. However, according to the experiment in which the flow rate of the cooling air was measured, it is difficult to adjust the flow rate of the cooling air flowing through the pair of thermopiles 430 when the pair of flow-rate adjusting orifices 450 are arranged upstream from the rear thermopile 430. The bracket 420c is arranged upstream from the rear thermopile 430. For this reason, there is little room for space.
In order to handle such a situation, in the present embodiment, the pair of flow-rate adjusting orifices 450 are arranged upstream from the front thermopile 430 and downstream from the rear thermopile 430. Due to the arrangement of the pair of flow-rate adjusting orifices 450 as in the present embodiment, the flow rates of the cooling air of the pair of thermopiles 430 can easily be adjusted to be equal to each other.
Removal of Thermopile Unit
In
The second supporting member 420 and the first supporting member 410 of thermopile unit 400 can be detached in the order listed. In order to achieve such detachment, firstly, only one of the multiple screws 291 is removed in
The first supporting member 410 still remains beside the heating roller unit 300. It is not necessary to remove the first supporting member 410 to inspect and replace the thermopile 430.
If the first supporting member 410 is left between the front panel 210F and the rear panel 210R, the second supporting member 420 can be reattached in a short time after the inspection and replacement of the thermopile 430. In this reattachment, the first supporting member 410 serves as a guide rail for the second supporting member 420.
The rear portion of the second supporting member 420 is inserted into the opening 250 of the front panel 210F, the second supporting member 420 is slid toward the rear in the longer-side direction of the first supporting member 410. In so doing, the rising portions 410a on both sides of the first supporting member 410 in the shorter-side direction guide both right and left sides of the second supporting member 420.
Accordingly, the bracket 420c of the second supporting member 420 at the rear can be smoothly aligned with the positioning pin 221 as illustrated in
Finally, the screw 291 is tightened to complete the attachment of the second supporting member 420. According to the present embodiment as described above, the second supporting member 420 can easily attached or detached.
If the first supporting member 410 is also detached from the state as illustrated in
As a result, the space between the front panel 210F and the rear panel 210R is widely opened as illustrated in
In the present embodiment, the second supporting member 420 is mounted on the first supporting member 410. Accordingly, the entirety of the thermopile unit 400 can be inserted through the opening 250 of the front panel 210F at a time. However, as a method of attachment, it is easier to insert the first supporting member 410 and the second supporting member 420 from the opening 250 step by step than inserting the entirety of the thermopile unit 400 at a time.
In other words, when the first supporting member 410 is inserted independently, the bent piece 410c at the rear can be easily seen through the opening 250 at the front. Accordingly, the bent piece 410c at the rear can easily be aligned with the pair of positioning pins 222 at the rear.
Position of Thermopile
The relative positions of the heating roller 310 to thermopile 430 are further described in detail with reference to
In
The pair of thermopiles 430 are arranged near both ends of the second supporting member 420 in the longer-side direction.
In
The upper portions of the heater lamp 320 make up a heating area A, and as illustrated in
The thermopile 430 on the right is arranged adjacent to a non-heating area or a non-sheet-passing area external to the heating area A of the upper heater lamp 320. The thermopile 430 on the left is arranged adjacent to a non-heating area or a non-sheet-passing area external to the heating area B of the lower heater lamp 320.
The installation angles that the pair of thermopiles 430 form with the heating roller 310 are adjusted to an angle at which the temperature of the non-sheet-passing area can be detected with a high degree of precision. As the temperature of the non-sheet-passing area tends to rise excessively, the temperature of the non-sheet-passing area is detected by thermopile 430 to control the electrical conduction of the heater lamp 320.
As illustrated in
As described above, the cooling air passes through the outer regions of the pair of thermopiles 430. By so doing, thermopile 430 can be effectively cooled and the accuracy of the detection improves.
Detailed Front and Rear Positioning
As described above, the pair of right and left positioning pins 221 in the upper portion are inserted into the pair of positioning holes formed on the bracket 420c of the rear end of the second supporting member 420. The pair of right and left positioning pins 222 in the lower portion are inserted into the positioning holes formed on the bent piece 410c of the rear end of the first supporting member 410.
A male connector 226 that is electrically conductive with the pair of thermopiles 430 are arranged on the positioning member 225 of the rear panel 210R. A female connector 230 through which the male connector 226 is coupled to the bracket 420c in a detachable manner from the longer-side direction of the second supporting member 420 is arranged on the bracket 420c of the thermopile unit 400.
As described above, the pair of right and left positioning pins 280 of the front panel 210F are inserted into the positioning holes formed on the bent piece 410b of the front end of the first supporting member 410.
The bent piece 410b of the first supporting member 410 is fixed to the front panel 210F as a screw 292 is screwed into a screw hole 261 (see
Flow of Cooling Air
The flow of the cooling air is described below with reference to
A fan 500 is arranged on the rear side of the rear panel 210R, and the cooling air that is blown out from the fan 500 is introduced to the rear side end of the cover 440 of the thermopile unit 400 through the air duct 240.
The air duct 240 penetrates the positioning member 225 and protrudes to the inner side of the rear panel 210R. When thermopile unit 400 is inserted into the apparatus as illustrated in
When the cooling air is introduced from the air duct 240 to the rear side of the cover 440, the cooling air flows through the cover 440 toward the front. The entire amount of the cooling air is exhausted to the outside through the through hole 440a of the cover 440, which is formed ahead of the pair of thermopiles 430 adjacent to the heating roller 310. In so doing, thermopile 430 is cooled, and the accuracy of the detection of the thermopile 430 can be maintained.
If the flow rates of the cooling air that flows through the pair of thermopiles 430 are different from each other, the accuracy of detection may deteriorate. In order to handle such a situation, the pair of flow-rate adjusting orifices 450 are arranged between the pair of thermopiles 430 as described above, and the flow rates of the cooling air that flows through the pair of thermopiles 430 are adjusted so as to be equal to each other.
Note that numerous additional modifications and variations are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the embodiments of the present disclosure may be practiced otherwise than as specifically described herein. For example, elements and/or features of different illustrative embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims.
For example, the supporting structure for the temperature sensor according to the present the present disclosure is applicable not just to the supporting structure for the temperature sensor used in the drying device, but to the supporting structure for a temperature sensor used to measure the temperature of various kinds of heating devices. For example, the supporting structure for the temperature sensor according to the present the present disclosure is applicable to the supporting structure for a temperature sensor provided for a fixing roller in fixing devices known in the art.
The supporting structure for the temperature sensor according to the present the present disclosure is also applicable to the supporting structure for, for example, an optical device such as a miniature camera or various kinds of sensors such as an optoelectronic detector and a close-proximity sensor, in addition to or in place of the temperature sensor.
Any one of the above-described operations may be performed in various other ways, for example, in an order different from the one described above.
Each of the functions of the described embodiments may be implemented by one or more processing circuits or circuitry. Processing circuitry includes a programmed processor, as a processor includes circuitry. A processing circuit also includes devices such as an application-specific integrated circuit (ASIC), digital signal processor (DSP), field-programmable gate array (FPGA), and conventional circuit components arranged to perform the recited functions.
Number | Date | Country | Kind |
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2022-090935 | Jun 2022 | JP | national |