JP7183637B2 - Fine particle collection device and image forming device - Google Patents

Description

The present invention relates to a fine particle collecting device and an image forming apparatus.

Conventionally, as a technique for collecting particulates in exhaust gas with a collecting means such as a filter and purifying the air before discharging the air into the atmosphere, the technology described in Patent Document 1 below is known.

Patent Document 1 describes a duct for merging exhaust air from a plurality of exhaust ports of an electrical device and discharging the exhaust air from one outlet into the atmosphere, and a filter and an electric fan built in front of the outlet of the duct. , an optional device for electrical equipment comprising an air flow sensor for detecting the presence or absence of exhaust from one of a plurality of air outlets, and a control device for controlling the operation of an electric fan based on the output of the air flow sensor , wherein the air flow sensor is arranged at an outlet having the highest exhaust air velocity among the plurality of outlets.

JP 2016-162759 A (paragraphs 0002, 0034-0036, FIG. 6)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fine particle collecting device and an image forming apparatus capable of collecting fine particles while preventing them from leaking to the outside of a ventilation pipe.

The fine particle collection device of the present invention (A1) comprises:
a vent pipe having a channel space for flowing air; a first air blowing means for sending air containing fine particles into the channel space on one end side of the vent pipe; and a collecting means for collecting fine particles contained in the air sent by the first air blowing means, and passing through the collecting means on the other end side of the ventilation pipe. a second air blowing means for collecting air and sending it out from the flow path space;
The vent pipe extends from the first flow passage space from the first air blowing means to the collection means in the flow passage space, and from the collection means to the second air blow means in the flow passage space. a second flow path space up to, a front flow path space portion existing along the longitudinal direction of the collection means at a position on the front side of the collection means in the first flow path space, and the front flow having an inlet through which air flows into the channel space portion, and an outlet through which the air in the second channel space that has passed through the collecting means is discharged to the second air blowing means;
The inflow port and the outflow port are arranged so as to exist at different end sides in the longitudinal direction of the collection means,
The front channel space portion has a first space portion on the side where the inflow port exists and a second space portion on the side where the inflow port does not exist, and faces the collecting means in the second space portion. The distance between the inner wall surface portion and the collecting means is smaller than the distance between the inner wall surface portion facing the collecting means and the collecting means in the first space portion,
The first air blowing means and the second air blowing means are arranged such that the pressure (P1) in the first flow path space and the pressure (P2) in the second flow path space satisfy the relationship of "P2<P1≦atmospheric pressure". It is kept and operated.

Further, the fine particle collection device of the present invention (A2) is the collection device of the invention A1, wherein the first air blowing means and the second air blowing means are configured such that the air volume (Q1) of the first air blowing means and the air volume (Q1) of the first air blowing means 2 The air volume (Q2) of the air blowing means operates while maintaining the relationship of "Q1<Q2".
Further, in the fine particle collecting device of this invention (A3), in the collecting device of the above invention A1 or A2, the first air blowing means is an axial fan .
The fine particle collecting device of this invention (A4) is the collecting device of any one of the above inventions A1 to A3, wherein the second air blowing means is a sirocco fan .

Further, the image forming apparatus of the present invention (B1) is equipped with the fine particle collecting device according to any one of A1 to A4 .
The image forming apparatus of the present invention (B2) is the image forming apparatus of the invention B1, further comprising fixing means for fixing the unfixed image by allowing the recording medium for holding the unfixed image to pass therethrough, wherein the collecting device comprises: One end of the ventilation pipe on the side where the first air blowing means is arranged is arranged to be connected to the fixing means.

According to the collecting device of Invention A1, it is possible to collect fine particles while preventing them from leaking to the outside of the ventilation pipe.
In addition, according to the collecting device of the invention A1, compared to the case where the inlet and the outlet are not arranged so as to exist on different end side in the longitudinal direction of the collecting means, Fine particles can be collected by effectively utilizing the longitudinal direction. Furthermore, according to the collecting device of the invention A1, compared to the case where the distance between the collecting means and the inner wall surface portion facing the collecting means in the front channel space portion of the vent pipe is the same throughout, It is possible to suppress clogging due to concentration of fine particles in a portion of the collecting means facing the discharge port of the collecting means.
According to the collecting device of the invention A2, the relationship of P2<P1≦atmospheric pressure can be easily realized.
According to the collecting device of the invention A3, compared with the case where the first air blowing means is not an axial fan, the air containing fine particles can be efficiently collected and sent into the flow path space of the ventilation pipe.
According to the collecting device of the invention A4, compared to the case where the second air blowing means is not a sirocco fan, even if there are fine particles that are not collected by the collecting means, the fine particles are allowed to adhere to the inner wall of the casing of the sirocco fan. can be captured .

According to the image forming apparatus of Invention B1, it is possible to collect fine particles generated in the image forming apparatus while preventing them from leaking to the outside of the ventilation pipe.
According to the image forming apparatus of the invention B2, it is possible to collect fine particles generated by the fixing means while preventing them from leaking to the outside of the ventilation pipe.

1 is a schematic diagram showing the configuration of an image forming apparatus according to Embodiment 1; FIG. 1 is a schematic perspective view showing the configuration of a fine particle collecting device according to Embodiment 1. FIG. 3 is a schematic perspective view showing the collection device of FIG. 2 when viewed from another direction; FIG. 4 is a schematic perspective view showing an enlarged part of the interior of the collection device of FIG. 3; FIG. FIG. 3 is a schematic cross-sectional view showing the collection device of FIG. 2; FIG. 4 is a schematic cross-sectional view showing the collection device as viewed in a cut plane at another angle; It is a schematic plan view which shows the upper end part of the ventilation pipe in a collection device. FIG. 3 is a block diagram showing a configuration related to control of the collection device of FIG. 2; FIG. 3 is a conceptual diagram showing an operation example of the collecting device of FIG. 2; FIG. 3 is a schematic cross-sectional view showing an operating state of the collecting device of FIG. 2; FIG. 11 is a schematic cross-sectional view showing the operating state of FIG. 10 as viewed in a cut plane at another angle; (A) is a schematic perspective view showing part of a collection device of a modification, and (B) is a schematic cross-sectional view of part of the collection device of (A) along the line BB. FIG. 13 is a schematic plan view showing part of the collection device of FIG. 12 in cross section; FIG. 13 is a schematic plan view, partly in section, showing an operating state of part of the collecting device of FIG. 12 ;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[Embodiment 1]
1 to 3 show Embodiment 1 of the present invention. FIG. 1 shows the overall configuration of an image forming apparatus 1 according to the first embodiment, and FIGS. 2 and 3 show the configuration of a fine particle collecting device according to the first embodiment.
Arrows indicated by symbols X, Y, and Z in each drawing indicate directions of width, height, and depth of a three-dimensional space assumed in each drawing. In FIG. 1, the circle mark at the intersection of the X and Y direction arrows indicates that the Z direction is vertically downward in the drawing.

<Overall Configuration of Image Forming Apparatus>
The image forming apparatus 1 is an apparatus that forms an image on a sheet of paper 9, which is an example of a recording medium, by electrophotography. The image forming apparatus 1 according to the first embodiment is configured as a printer that forms an image corresponding to image information acquired from an external device such as an information terminal. Image information is information that constitutes an image such as characters, graphics, patterns, and photographs.

The image forming apparatus 1 has a housing 10 as shown in FIG. 5. A fine particle collection device 6 and the like are mainly arranged. The dashed-dotted line shown in FIG. 1 is the main transport path along which the paper 9 is transported inside the housing 10 .

The housing 10 is a structure having a box-like appearance, and is constructed using various supporting members, exterior materials, and the like. An operating means 12 is arranged outside the housing 10 . The operating means 12 includes, for example, a display section for displaying various information, an input section for performing selection operations and input work, and the like. A control means 14 is arranged inside the housing 10 . The control unit 14 is a unit having a function of comprehensively controlling various operations in the image forming apparatus 1 . The control means 14 is composed of, for example, an arithmetic processing circuit, storage means, input/output means, a control section for controlling them, and the like.

The image forming means 2 is a means for forming a toner image composed of toner as a developer using an electrophotographic system. As shown in FIG. 1, the image forming means 2 in Embodiment 1 individually forms toner images of four colors, for example, yellow (Y), magenta (M), cyan (C) and black (K). It is composed of four image forming units 20Y, 20M, 20C and 20K.

Each of the four image forming units 20 (Y, M, C, K) has a photosensitive drum 21 which is an example of a photosensitive member driven to rotate in the direction indicated by the arrow A. , a charging device 22, an exposure device 23, a developing device 24 (Y, M, C, K), a primary transfer device 25, a first cleaning device 26, and the like are arranged. In FIG. 1, the reference numerals 21 to 26 are all indicated for the image forming unit 20K, but only some of the reference numerals are indicated for the other color image forming units 20 (Y, M, C). is omitted.

Among them, the charging device 22 is a device for charging the outer peripheral surface portion of the photosensitive drum 21, which is an image forming area, to a required potential. The charging device 22 includes, for example, a charging member such as a roll that is brought into contact with the image forming area on the outer surface of the photosensitive drum 21 and supplied with a charging current. The exposure device 23 is a device that irradiates the charged outer peripheral surface of the photosensitive drum 21 with light generated from image information to form an electrostatic latent image of each color component. The exposure device 23 operates upon receiving an image signal obtained by decomposing image information input from the outside into the four color components (Y, M, C, K) by image processing means (not shown). The developing device 24 (Y, M, C, K) develops the electrostatic latent image of each color component formed on each photosensitive drum 21 by supplying toner of a color corresponding to the color component to develop the four colors ( This is an apparatus for visualizing a toner image of any one of Y, M, C, and K).

The primary transfer device 25 is a device that primarily transfers the toner image formed on each photosensitive drum 21 in each image forming unit 20 (Y, M, C, K) to the intermediate transfer means 3 . The primary transfer device 25 includes, for example, a primary transfer member such as a roll that contacts the outer peripheral surface of the photosensitive drum 21 via an intermediate transfer belt 31 (to be described later) and is supplied with a primary transfer current. Further, the primary transfer device 25 constitutes a part of the intermediate transfer means 3 as will be described later. The first cleaning device 26 is a device that removes unnecessary substances such as toner adhering to the outer peripheral surface of the photosensitive drum 21 and cleans it.

The intermediate transfer means 3 temporarily holds and conveys the toner image formed by each image forming unit 20 (Y, M, C, K) in the image forming means 2 by primary transfer, and finally onto the paper 9. It is means for secondary transfer. As shown in FIG. 1, the intermediate transfer means 3 in Embodiment 1 holds the toner image primarily transferred from the photosensitive drum 21 of the image forming unit 20 (Y, M, C, K) and performs secondary transfer. It is configured by a belt system using an intermediate transfer belt 31 that conveys to a position.

Of these, the intermediate transfer belt 31 is an annular belt capable of holding a toner image by electrostatic action. The intermediate transfer belt 31 is supported by a plurality of support rolls 32a to 32e so as to rotate (circularly move) while successively passing through each primary transfer position where primary transfer is performed on the image forming units 20 (Y, M, C, K). It is supported under the required tension. Further, the intermediate transfer belt 31 is driven to rotate in the direction indicated by arrow B by a support roll 32a as a drive roll. The primary transfer position is a portion where the intermediate transfer belt 31 and the primary transfer device 25 face each other.

The primary transfer device 25 and the like in each image forming unit 20 (Y, M, C, K) are arranged on the inner circumferential surface side of the intermediate transfer belt 31 . A secondary transfer device 35 , a second cleaning device 36 , and the like are arranged on the outer peripheral surface side of the intermediate transfer belt 31 .
The secondary transfer device 35 is a device that secondarily transfers the toner image that has been primarily transferred onto the outer peripheral surface of the intermediate transfer belt 31 onto the paper 9 . The secondary transfer device 35 includes, for example, a secondary transfer member such as a roll that contacts the outer peripheral surface portion of the intermediate transfer belt 31 supported by a support roll 32d as a secondary transfer backup roll. A secondary transfer current is supplied to the support roll 32d or the secondary transfer member. The second cleaning device 36 is a device that cleans the outer peripheral surface of the intermediate transfer belt 31 by removing unnecessary substances such as toner.

The paper feeding means 4 is a means for containing the paper 9 used for image formation and supplying it to the secondary transfer position where the secondary transfer of the intermediate transfer means 3 is performed. As shown in FIG. 1, the paper feeding means 4 in Embodiment 1 includes a paper container 41, a delivery device 43, and the like. The secondary transfer position is a portion of the intermediate transfer means 3 where the intermediate transfer belt 31 and the secondary transfer device 35 face each other.

The paper container 41 is, for example, a device that is attached to the housing 10 so as to be able to be pulled out, and contains the paper 9 of a desired size, type, etc. in a stacked state on a stacking plate (not shown). The delivery device 43 is a device that delivers the sheets 9 one by one from the sheet container 41 . The paper 9 may be any medium as long as it can be transported through the transport path in the housing 10 and hold and fix the toner image.

The fixing means 5 is means for fixing the toner image, which is an unfixed image transferred to the paper 9, onto the paper 9. As shown in FIG. As shown in FIG. 1, the fixing means 5 in Embodiment 1 includes a heating rotating body 52 and a pressing rotating body 52 in the inner space of a box-shaped housing 51 in which an inlet and an outlet for the paper 9 are formed. It is configured by arranging the body 53 and the like.

The heating rotator 52 is a structure having a roll shape, a belt shape, a belt-nip shape, or the like. The heating rotator 52 is heated and held at a required temperature by a heating means (not shown), and is supported by a driving means (not shown) so as to be rotated in the direction indicated by the arrow. The pressing rotator 53 is a structure having a roll shape, a belt shape, a belt-nip shape, or the like. The pressing rotator 53 is arranged so as to contact the heating rotator 52 with a required pressure by a pressurizing means (not shown), and is supported so as to follow the rotation of the heating rotator 52 and be rotated. It is
In the fixing means 5, the sheet 9 having the toner image transferred thereon is passed through a portion where the heating rotating member 52 and the pressing rotating member 53 are in contact with each other, and a fixing processing section (fixing nip) is provided for performing fixing processing such as heating and pressing. part) FN.

Further, in the image forming apparatus 1, as shown in FIG. 1, a transport path illustrated below is provided inside the housing 10. As shown in FIG.
For example, between the paper supply means 4 and the secondary transfer position of the intermediate transfer means 3, there is provided a paper supply transport path Rt1 for transporting the paper 9 delivered from the paper supply means 4 to the secondary transfer position. . The paper feed transport path Rt1 is configured by arranging, for example, a plurality of transport rolls 45a to 45d and a plurality of transport guide members (not shown).
Between the fixing device 5 and the secondary transfer position of the intermediate transfer device 3, a relay transport path Rt2 is provided for transporting the sheet 9 to the fixing device 5 after the secondary transfer is finished. The relay transport path Rt2 is configured by arranging sheet transport devices 46a and 46b of a belt transport type, for example.
Further, an ejection transport path Rt3 is provided between the fixing means 5 and the paper ejection port 11 in the housing 10 to transport the paper 9 after fixing to the paper ejection port 11 . The discharge transport path Rt3 is configured by arranging transport rolls 47a and 47b, a transport guide member (not shown), and the like.

According to the image forming apparatus 1 configured as described above, by selecting and operating the four image forming units 20 (Y, M, C, and K) as the image forming means 2, images of the following types can be obtained. can be formed (printed).
For example, by operating all of the image forming units 20 (Y, M, C, K), a multi-color image formed by combining toners of four colors (Y, M, C, K), a so-called full-color image, is formed in the intermediate image. It can be formed on paper 9 via transfer means 3 and fixing means 5 . Further, by operating any one of the image forming units 20 (Y, M, C, K), a monochrome image made of one color toner is formed on the paper 9 via the intermediate transfer means 3 and the fixing means 5. be able to. Furthermore, by operating two or three of the image forming units 20 (Y, M, C, K), it is possible to similarly form a multi-color image other than a full-color image, which is composed of a plurality of color toners. .

<Structure related to particle collection device>
The fine particle collecting device 6 is a device for collecting fine particles generated from the fixing means 5 and its surroundings in the image forming apparatus 1 .
The fine particles to be collected by the collecting device 6 are, for example, fine particles (dust) having a particle size of 1 μm or less generated by cooling after volatilization of components such as wax contained in the toner due to heating during the fixing process. is. Further, the fine particles at this time are preferably fine particles containing so-called ultra fine particles (UFP) having a particle size of 0.1 μm or less or less.

As shown in FIGS. 2 to 6 and the like, the fine particle collecting device 6 includes a vent pipe 61, a first blowing means 62, a collecting means 63, a second blowing means 64, and the like. The collecting device 6 according to the first embodiment is configured to collect fine particles generated by the fixing means 5 .

Among these, the ventilation pipe 61 is a structure having a flow path space 60 for flowing air.
As shown in FIGS. 1 and 5, the ventilation pipe 61 in Embodiment 1 has one end connected to a collection duct 56 provided above the housing 51 of the fixing means 5, and the other end connected to the second end. 2 is arranged to be connected to the air blowing means 64 . The collection duct 56 collects the air present in the housing 51 and its surroundings from a plurality of intake ports 56a formed at positions above the paper 9 inlet and outlet in the housing 51 of the fixing means 5. is to be incorporated into
Further, the vent pipe 61 rises upward along the inner wall portion of the housing 10 of the image forming apparatus 1 from the rear end of the housing 51 of the fixing unit 5 to reach the rear upper end corner of the housing 10 . It extends to a position on the front side of an exhaust port 13 (FIG. 5) provided in the part.

More specifically, as shown in FIGS. 2 and 3, the vent pipe 61 has a truncated pyramid-shaped passage space 60 enlarged so as to allow the placement of the first air blowing means 62 at its lower end. An enlarged portion 61A, an enlarged upper end portion 61B having a rectangular parallelepiped channel space 60 enlarged so as to allow the arrangement of the collection means 63, and an enlarged lower end portion 61A and an enlarged upper end portion 61B extending to connect the enlarged portion 61A and the enlarged upper end portion 61B. It is configured as a structure having a shape including an intermediate portion 61C having a channel space 60 having a rectangular cross section.

As shown in FIGS. 1, 5, etc., the space between the enlarged lower end portion 61A of the air pipe 61 or the first air blowing means 62 and the fixing means 5 is present in the housing 51 of the fixing means 5 and its peripheral portion. A collection connection 65 is arranged for collecting and connecting the air flowing through the collection duct 56 .
As shown in FIGS. 2 and 3, the intermediate portion 61C of the ventilation pipe 61 includes an intermediate lower portion 61Ca that rises upward from the enlarged lower end portion 61A, and an approximately horizontal portion after expanding and rising from the raised intermediate lower portion 61Ca. It is composed of an intermediate upper portion 61Cb that is bent in a direction and reaches a portion of the enlarged upper end portion 61B and is connected thereto.
Furthermore, as shown in FIGS. 4 to 7, the upper end expanded portion 61B of the air pipe 61 has an inlet 66 connected to the intermediate portion 61C (intermediate upper portion 61Cb) through which air flows, and a collecting means 63. A discharge port 67 is provided through which the air that has passed through is discharged to the second blower means 64 .

Next, the first air blowing means 62 is an air blowing means for sending air containing fine particles into the flow path space 60 on one end side of the ventilation pipe 61 .

The first air blowing means 62 is preferably air blowing means having a performance capable of efficiently collecting fine particles generated in the fixing means 5 and its peripheral portion together with air and sending the fine particles into the flow path space 60 of the ventilation pipe 61 . .
In Embodiment 1, an axial fan is applied as the first air blowing means 62 . Further, in Embodiment 1, the first air blowing means 62 is arranged so as to exist in the widest portion of the flow passage space 60 in the enlarged lower end portion 61A of the air pipe 61 .

For example, as shown in FIGS. 5 and 6, the axial fan as the first air blowing means 62 is present in a frame portion 621 having a through portion 621a having a circular cross section and a through portion 621a of the frame portion 621. It is composed of a shaft portion 622 rotatably supported by the base and having a built-in drive motor (625: FIG. 8), and a plurality of blade portions 623 erected around the shaft portion 622. As shown in FIG.

Next, the collecting means 63 is disposed in the flow channel space 60 in the middle of the ventilation pipe 61 in a state of blocking the flow channel, and collects fine particles contained in the air sent by the first air blowing means 62. It is a means to

In Embodiment 1, the collecting means 63 is arranged so as to cross the channel space 60 at the upper end enlarged portion 61B of the air pipe 61 at a substantially intermediate position. The collecting means 63 at this time is arranged to have a relatively long shape (form) in one transverse direction. Moreover, the direction in which the collecting means 63 crosses at this time is the longitudinal direction C of the collecting means 63 .
Further, in Embodiment 1, as the collecting means 63, one having a performance capable of collecting fine particles contained in the air and a performance capable of collecting even ultrafine particles is applied. . Specifically, as the collecting means 63, a filter is used that has a relatively high initial pressure loss (for example, 50 Pa or more at a flow velocity of 1 m/s) and a collection efficiency of 95% or more for fine particles. .
Furthermore, in Embodiment 1, as the collecting means 63, as shown in FIGS. 4 and 5, a pleated filter (a shape in which peaks and valleys are continuously folded) is applied. For example, as shown in FIGS. 2 and 3, the filter as the collection means 63 is passed through a mounting opening provided corresponding to the position where the collection means 63 of the enlarged upper end portion 61B of the ventilation pipe 61 is mounted. It can be replaced by detaching. In addition, the ventilation pipe 61 is provided with a replacement grip portion 61D that is gripped when the collecting means 63 is replaced through the mounting opening thereof.

Next, the second air blowing means 64 is air blowing means for collecting the air passing through the collecting means 63 on the other end side of the vent pipe 61 and sending it out from the flow path space 60 .

The second air blowing means 64 is preferably air blowing means capable of making the inside of the passage space 60 of the vent pipe 61 negative pressure. In addition, the second air blowing means 64 includes a housing having an inner wall surface on which fine particles not collected by the collecting means 63 can adhere, and generates an air flow that collides with the inner wall surface of the housing. It is preferable that the air blowing means is of a type that allows the air to flow. A multi-blade centrifugal fan, for example, can be applied as such a second air blowing means 64 .

In Embodiment 1, a sirocco fan, which is one of multi-blade centrifugal fans, is applied as the second air blowing means 64 .
Further, in Embodiment 1, the second air blowing means 64 is arranged so as to face the discharge port 67 provided in the upper surface portion 61Ba of the enlarged upper end portion 61B of the air pipe 61 .
Furthermore, in the first embodiment, as shown in FIGS. 2 to 4, an exhaust guide for guiding the air sent from the second air blower 64 to the exhaust port 13 in the housing 10 of the image forming apparatus 1 is provided. Means 69a, 69b are provided. The exhaust guide means 69a and 69b are configured using, for example, plate-like members.

The sirocco fan as the second air blowing means 64 is, for example, as shown in FIGS. 641b, a shaft portion 642 that is rotatably supported on the top surface of the accommodation space of the housing 641 and has a built-in drive motor (645: FIG. 8), and is attached around the shaft portion 642. and a multi-blade rotating portion 643 in which a large number of blades are arranged in a cylindrical shape at regular intervals and rotates within the accommodation space of the housing 641 .
This sirocco fan is arranged with the intake hole 641 a of the housing 641 facing the discharge port 67 of the ventilation pipe 61 . Further, the exhaust passage portion 641b of the housing 641 in this sirocco fan is configured as a passage portion for exhausting air along the upper surface portion 61Ba of the enlarged upper end portion 61B of the vent pipe 61 as shown in FIG. However, the passage may be such that the air is exhausted in a direction other than that.

5 and 6, the first air blowing means 62 and the second air blowing means 64 in the collection device 6 collect air from the first air blowing means 62 in the flow passage space 60 of the ventilation pipe 61, as shown in FIGS. A first pressure (P1) in the first flow passage space 60A up to the means 63 and a second 2 pressure (P2) is configured to operate while maintaining the relationship of "P2<P1≤atmospheric pressure".

Here, the atmospheric pressure is strictly the atmospheric pressure outside the vent pipe 61 when the collecting device 6 is in operation, but it is substantially the same as the atmospheric pressure outside the housing 10 of the image forming apparatus 1 . be. The first pressure (P1) is preferably a pressure (negative pressure) lower than the atmospheric pressure, but may be the same pressure as the atmospheric pressure. Furthermore, the second pressure (P2) may be any pressure lower than the first pressure (P1).
Also, the first pressure (P1) is measured by a first pressure measuring means 71 arranged in the first flow path space 60A. The second pressure (P2) is measured by a second pressure measuring means 72 arranged within the second flow path space 60B. As the first pressure measuring means 71 and the second pressure measuring means 72, for example, internal pressure gauges capable of measuring negative pressure are applied.

Moreover, the first air blowing means 62 and the second air blowing means 64 in the collection device 6 are such that the first air volume (Q1) of the first air blowing means 62 and the second air volume (Q2) of the second air blowing means 64 are "Q1< Q2” relationship is maintained and operated.

Here, the first air volume (Q1) is the air volume obtained according to the rotational speed of the first air blowing means 62 . Also, the second air volume (Q2) is the air volume obtained according to the rotational speed of the second air blowing means 64 . Therefore, the first air volume (Q1) and the second air volume (Q2) can be adjusted by changing the rotational speed of the first air blowing means 62 and the rotational speed of the second air blowing means 64.
The first air volume (Q1) and the second air volume (Q2) are generally the amount of air moved per unit time, and are numerical values obtained as a multiplier of the passing air speed (m/s) and the passing area (m ² ). (m ³ /h). Then, the first air volume (Q1) and the second air volume (Q2) in the collection device 6 are measured using a measuring means such as an anemometer, for example.

As shown in FIG. 8, the collection device 6 has control means (control section) 70 for controlling its operation.
The control means 70 has the same configuration as the control means 14 in the image forming apparatus 1, and is configured as a control system independent of the control means 14, or operates as a part of the control means 14. configured to When the control means 70 is a control system independent of the control means 14 , the start and end of its operation are controlled by the control means 14 .

Then, as shown in FIG. 8, the control means 70 includes a first pressure measuring section (measuring means) 71 for measuring the first pressure (P1) in the first flow path space 60A in the vent pipe 61, the vent pipe 61 A second pressure measuring unit (measuring means) 72 that measures the second pressure (P2) in the second flow path space 60B in the second flow path space 60B, PV information that acquires count information of the cumulative number of printed sheets 9 (PV: Print Volume) It is connected to an acquisition unit (acquisition means) 15 or the like, and thereby inputs information necessary for control processing.
The first pressure measuring section 71 and the second pressure measuring section 72 are configured by the above-described internal pressure gauges arranged in the first flow path space 60A and the second flow path space 60B. The PV information acquisition unit 15 is configured to acquire PV information counted by the control unit 14 of the image forming apparatus 1 and stored and held in the storage unit.

Further, as shown in FIG. 8, the control means 70 is connected to a blowing drive control section 75 for controlling the driving of the blowing operation of the first blowing means 62 and the second blowing means 64, thereby performing necessary control. Information is output to the blower drive control section 75 .
The air-blowing drive control unit 75 controls each operation of a drive motor 625 that drives the first air blower 62 when air is blown and a drive motor 645 that drives the second air blower 64 when air is blown. The number of revolutions (rotation speed) of 645 can also be controlled.

Further, as shown in FIG. 8, the control means 70 has a storage unit 73 for storing programs and data necessary for control and information obtained in the process of control operation. and has the following information processing functions for processing information based on data, etc.
The information processing function includes a calculation unit 76 that calculates the pressure difference ΔP between the first pressure (P1) and the second pressure (P2), and the number of rotations of the first blower means 62 and the second blower means 64 during blowing. It has an adjustment unit 77 for adjustment, an arrival detection unit 78 for detecting that the filter, which is the collecting means 63, has reached its pre-life and provisional life.

Among them, the pressure difference ΔP calculator 76 calculates the pressure difference ΔP (=P1− P2) is calculated.
In addition, the rotation speed adjustment unit 77 functions to adjust the rotation speeds of the drive motors 625 and 645 during air blowing so that the pressure difference ΔP obtained by the calculation unit 76 is kept within a predetermined range. It is desirable that the adjusting unit 77 adjust the number of rotations of both the driving motors 625 and 645 of the first blowing means 62 and the second blowing means 64, but it is possible to keep the pressure difference ΔP within a certain range. For example, as will be described later, only the number of revolutions of the drive motor 645 of the second blower means 64 may be adjusted.
Further, a filter pre-life and provisional service life detection unit 78 detects when the number of revolutions obtained from the adjustment unit 77 reaches each specified number of revolutions corresponding to a predetermined pre-service life and provisional service life. The pre-life is set, for example, when the collection efficiency of the filter drops from the initial value by a required percentage. The provisional service life is set, for example, at the time when the collection efficiency of the filter is further reduced by a required percentage from the value at the time of the pre-service life. In addition, data D<b>1 of prescribed rotation speeds for pre-life and provisional life used by the arrival detection unit 78 is stored in the storage unit 73 .

Furthermore, as shown in FIGS. 4 to 6, the ventilation pipe 61 in the collection device 6 is positioned in front of the collection means 63 in the first flow path space 60A and extends in the longitudinal direction of the collection means 63. As shown in FIGS. 60 C of front flow-path space parts which exist along C are provided.

A portion of the front flow path space portion 60C is formed with the above-described inlet port 66 for actually causing the air in the first flow path space 60A to flow into the front flow path space portion 60C. In addition, this front flow path space portion 60C makes it possible for the air to evenly contact the entire area in the longitudinal direction C of the filter, which is the collecting means 63, and functions to increase the thickness of the filter in a pseudo manner. do.

As for the ventilation pipe 61 in the collecting device 6, as shown in FIGS. 4 to 7, the inflow port 66 and the discharge port 67 are located along the longitudinal direction of the collecting means 63 in the ventilation pipe 61 (upper end enlarged portion 61B). They are arranged so that they are offset to different end sides in the direction C. FIG.

In Embodiment 1, an opening having a rectangular opening shape is provided as the inflow port 66 , and the inflow port 66 is positioned in the front channel space portion 60C of the upper end enlarged portion 61B of the vent pipe 61 in the collection means 63 . It is provided at a portion extending from one end in the longitudinal direction C to approximately half the position in the longitudinal direction C. As shown in FIG. Further, in Embodiment 1, an opening having a circular opening shape is provided as the discharge port 67, and the discharge port 67 is located at the upper end enlarged portion 61B of the vent pipe 61 at the other side of the collecting means 63 in the longitudinal direction C. It is provided at a site close to the end of the .

5 and 6, the front channel space portion 60C of the vent pipe 61 is divided into a first space portion 60Ca on the side where the inlet 66 exists and a second space on the side where the inlet 66 does not exist. A channel space having a portion 60Cb.
Moreover, in the front channel space portion 60C, the distance H2 between the collecting means 63 and the inner wall surface portion 68a facing the collecting means 63 of the second space portion 60Cb is equal to the collecting means of the first space portion 60Ca. The inner wall surface portion 61Bc facing the collector 63 and the collecting means 63 are arranged to have a relationship smaller than the distance H1 (H2<H1).
The distance H2 in the second spatial portion 60Cb is set to a value of 2 cm or less, for example.

In Embodiment 1, as shown in FIGS. 4 and 6, the second space portion 60Cb has a longitudinal extension of the collecting means 63 at a position closer to the collecting means 63 than the inner wall surface portion 61Bc of the first space portion 60Ca. A raised bottom portion 68 having a planar inner wall surface portion 68a extending along the direction C is provided, thereby establishing a size relationship (H2<H1) between the distances H1 and H2.
The raised bottom portion 68 has a slope that continuously rises from the inner wall surface portion 61Bc of the first space portion 60Ca toward the inner wall surface portion 68a of the raised bottom portion 68 on the end side that is the boundary with the first space portion 60Ca. It has a portion 68b.

<Operation of collection device>
For example, the fine particle collecting device 6 configured as described above operates as follows.

The collection device 6 operates in conjunction with the operation of the image forming apparatus 1 at least during operation (period).
Specifically, the collecting device 6 causes the control means 70 to drive the driving motor 625 of the first blowing means (axial fan) 62 and the driving motor 645 of the second blowing means (sirocco fan) 64 respectively. operated by

In the collecting device 6 at this time, the number of revolutions of the first air blowing means 62 and the second air blowing means 64 is controlled by the control means 70, so that the first pressure P1 in the first flow passage space 60A of the vent pipe 61 is and the second pressure P2 in the second flow path space 60B of the air pipe 61 are maintained in the above specific relationship (P2<P1≦atmospheric pressure).
Further, in the collecting device 6 at this time, the rotational speeds of the first blowing means 62 and the second blowing means 64 are controlled by the control means 70, so that the air volume Q1 of the first blowing means 62 and the air volume Q1 of the second blowing means 64 The air volume Q2 is maintained in the above specific relationship (Q1<Q2). In particular, by operating the first air blowing means 62 and the second air blowing means 64 so as to maintain the relationship of Q1<Q2, the relationship of P2<P1≦atmospheric pressure is relatively improved compared to the case where the relationship is not operated. easily implemented. Note that this specific relationship regarding air volume is realized by maintaining a relationship in which the rotational speed of the second air blowing means 64 is higher than the rotational speed of the first air blowing means 62, as shown in FIG. ing.

When the collecting device 6 operates in this way, as shown in FIGS. 10 and 11, the air containing fine particles generated by the fixing means 5 is blown by the collecting duct 56 mainly by the blowing action of the first blowing means 62. After being collected, it is fed into the first flow space 60A of the vent tube 61 through the collection connection 65 as illustrated by arrow E1.
At this time, since the first air blowing means 62 is an axial fan, the air containing fine particles is efficiently collected and sent into the first circulation space 60A compared to the case where the axial fan is not used.

Next, as shown in FIGS. 10 and 11, the air (E1) moves through the first circulation space 60A of the ventilation pipe 61 by the blowing action of the second blowing means 64 and is illustrated by arrows E2 and E3. After passing through the collection means 63 as described above, it is sent out through the exhaust port 67 from the second flow path space 60B as illustrated by an arrow E4. The air (E1) at this time is finally discharged from the exhaust passage 641b of the second blower 64 to the outside of the housing 10 through the exhaust port 13 of the housing 10 of the image forming apparatus 1, as illustrated by an arrow E5. be done.
At this time, fine particles contained in the air are collected by the collection means 63 when passing through the collection means 63 . As a result, the air that is sent out from the second air blowing means 64 becomes purified air free of fine particles.
Note that even if there are particles that are not captured by the collecting means 63, since the second blowing means 64 is a sirocco fan, the particles are more likely to flow with the air than when the sirocco fan rotates multiple blades. Centrifugal force due to the rotation of the portion 643 collides with or contacts the inner wall surface of the housing 641, and as a result, the fine particles are carried to the inner wall surface of the housing space in the housing 641 and the inner wall surface of the exhaust passage portion 641b. can be caught by adhering to

As described above, according to the collecting device 6, the first pressure P1 in the first flow path space 60A and the second pressure P2 in the second flow path space 60B in the vent pipe 61 are "P2<P1≤atmospheric pressure". Therefore, air containing fine particles generated by the fixing means 5 is kept in a state where it is difficult for it to leak out of the ventilation pipe 61 and is conveyed so as to pass through the collecting means 63 . As a result, fine particles contained in the air are collected by the collection means 63 .

Further, in the collecting device 6, the air (E1) sent into the first flow path space 60A of the ventilation pipe 61 flows as illustrated by an arrow E2 as shown in FIGS. After flowing into the front channel space portion 60C from the inlet 66, it is sent toward the collection means 63 as illustrated by an arrow E3.

At this time, the air (E2) that has flowed into the front flow path space portion 60C flows through arrows E3a, E3b, and E3c in FIG. After being in a state of being widely diffused as illustrated, they move in a state in which they can come into contact with the entire length of the collecting means 63 in the longitudinal direction C. As shown in FIG.
As a result, in the collecting device 6, the entire region in the longitudinal direction C of the collecting means 63 is effectively used, and the fine particles are efficiently collected.

At this time, the air (E2) that has flowed into the front flow path space portion 60C passes through the second air blowing means through the exhaust port 67 that is biased toward the end portion side different from the inflow port 66 in the longitudinal direction C of the collecting means 63. 64 air blow (intake) action.
As a result, in the collecting device 6, the air passing through the collecting means 63 moves in such a manner as to obliquely penetrate the collecting means 63 in its longitudinal direction C, as illustrated by an arrow E6 in FIG. As a result, the entire area of the collecting means 63 in the longitudinal direction C is also effectively used, and the particles are efficiently collected.

Further, at this time, the air (E2) that has flowed into the front flow path space portion 60C flows through the space between the collecting means 63 and the bottom-raising portion 68 provided in the second space portion 60Cb where the inflow port 66 does not exist. Since it is narrower than the first space portion 60Ca where the inlet 66 exists, it becomes difficult to flow into the second space portion 60Cb compared to the first space portion 60Ca.
As a result, in the collecting device 6, the air passing through the collecting means 63 can easily move diagonally through the collecting means 63 as illustrated by the arrow E6 in FIG. Also, the entire area in the longitudinal direction C of the collecting means 63 is effectively utilized, and the collection of fine particles is efficiently performed.

Furthermore, in the collection device 6, since the bottom raised portion 68 is provided in the second space portion 60Cb, local clogging of the collection means 63 is suppressed as described below.

That is, if the second space portion 60Cb were not provided with the raised bottom portion 68, the air blowing (intake) action of the second air blowing means 64 would be biased toward one end in the longitudinal direction C of the collecting means 63. Through the exhaust port 67 present at the bottom, the portion of the collecting means 63 facing the exhaust port 67 is relatively strongly affected. For this reason, in the collecting means 63, a relatively large amount of air passes through the portion facing the exhaust port 67, and the fine particles are collected intensively in that portion, resulting in local clogging. easier to get into.
On the other hand, in this collection device 6, the air that has flowed into the front flow path space portion 60C is relatively less likely to flow into the second space portion 60Cb having the raised bottom portion 68 than to the first space portion 60Ca. As a result, the proportion of air passing through the portion facing the exhaust port 67 of the collecting means 63 is reduced, and it becomes difficult for the portion to be locally clogged due to concentrated collection of fine particles in that portion. .

In addition, the collection device 6 is configured such that the length of the first flow passage space 60A in the vent pipe 61 is longer than the length of the second flow passage space 60B.
As a result, the air containing fine particles sent into the first flow path space 60A of the ventilation pipe 61 by the blowing action of the first air blowing means 62 stays in the first flow path space 60A for a period of time equal to that of the second flow path space 60B. It is relatively longer than the time spent inside. For this reason, in the collection device 6, compared to the case where the channel length of the first channel space 60A is shorter than the channel length of the second channel space 60B, fine particles contained in the air are reduced. , the rate of contact with the inner wall surface of the first flow path space 60A increases in the stage before passing through the collecting means 63, and the particles tend to adhere to the inner wall surface and be easily captured.

In the collecting device 6, the control means 70 controls the rotational speeds of the first blowing means 62 and the second blowing means 64 as follows.

That is, in the collecting device 6, using the measurement information of the first pressure P1 and the second pressure P2 respectively measured by the first pressure measuring means (measuring section) 71 and the second pressure measuring means (measuring section) 72, While the pressure difference ΔP (=P1−P2) is calculated by the pressure difference ΔP calculator 76 in the control means 70, the control means 70 is controlled so that the calculated pressure difference ΔP falls within a predetermined numerical range. The number of revolutions of the first air blowing means 62 and the number of revolutions of the second air blowing means 64 are adjusted by increasing or decreasing the number of revolutions by a necessary amount.

In this control, as shown in FIG. 9, the collection efficiency of the filter, which is the collection means 63, fluctuates mainly in the direction of deterioration due to use, and the passage rate (air resistance) of the air collection means 63 also fluctuates. However, since the first pressure P1 and the second pressure P2 also fluctuate under the influence of this, this is done in order to maintain the relationship "P2<P1≦atmospheric pressure".
At this time, the constant numerical range of the pressure difference ΔP is a numerical range required to maintain the difference value in the magnitude relationship of P2<P1, which is predetermined from the relationship “P2<P1≦atmospheric pressure”. . At this time, the rotational speeds of both the first blower means 62 and the second blower means 64 are adjusted. is adjusted to maintain the relationship of "Q1<Q2".

In addition, in this collecting device 6, the number of fine particles generated by the fixing means 5 tends to be the greatest when the fixing means 5 is new. An "initial collection mode" is implemented in which both the means 62 and the second blower means 64 are controlled to operate while maintaining the rotational speed in a range of relatively high values.
This initial collection mode ends, for example, when the cumulative number of sheets (PV) of the printing operation performed from the start of use of the new fixing unit 5 reaches a predetermined specified number of sheets. This determination of the end time is performed by acquiring and detecting information on the cumulative number of prints from the PV information acquisition section 15 in the control means 70 . The specified number of sheets at this time is set to, for example, 2800 sheets.
The collection device 6 is controlled in this initial collection mode, so that fine particles that are frequently generated when the fixing means 5 is brand new are properly collected.

In addition, in this collecting device 6, the amount of fine particles generated by the fixing means 5 tends to decrease after the control period of the initial collection mode has passed. Thus, the "collection gradual reduction mode" is executed in which both the first air blowing means 62 and the second air blowing means 64 are controlled to operate while being changed in the direction in which the rotational speed thereof is reduced.
In this collection gradual reduction mode, the rotational speeds of both the first blower means 62 and the second blower means 64 are continuously reduced at a constant rate at predetermined times, or they are reduced stepwise according to the PV information. Let Also, the collection gradual decrease mode ends when, for example, the information on the cumulative number of prints reaches a specified number different from the specified number in the initial collection mode.
The collection device 6 is controlled in this collection gradual decrease mode, so that appropriate collection of fine particles corresponding to the state of generation of fine particles is performed.
This collection gradual decrease mode may be omitted. In this case, immediately after the initial collection mode ends, a transition is made to a silent/low-power collection mode, which will be described later.

In addition, in this collection device 6, the amount of fine particles generated by the fixing means 5 decreases after the control timing of the collection gradual decrease mode (or the initial collection mode). As shown in , both the first blower means 62 and the second blower means 64 are operated while being maintained at the minimum required rotation speed selected from the viewpoint of giving priority to noise reduction and low power consumption. A "silent, low-power collection mode" is implemented.
Even in this silent, low-power collection mode, control is similarly executed to adjust the rotational speeds of the first blower means 62 and the second blower means 64 so that the pressure difference ΔP is kept within a certain range. This is the same for the collection gradual decrease mode and other collection modes described later.
Also, as shown in FIG. 9, the quiet/low-power collection mode is started when the collection gradual decrease mode (or the initial collection mode) ends, while the filter as the collection means 63 It ends when the pre-life is reached.
The collection device 6 is controlled in this silent/low-power collection mode, thereby properly collecting fine particles while reducing noise and power consumption.

Here, the arrival of the pre-life of the filter is detected by a filter pre-life and provisional life detection section 78 in the control means 70 . In this case, as shown in the upper part of FIG. 9, the detection by the arrival detection unit 78 is performed by detecting when the number of revolutions of the air blowing means reaches a specified number of revolutions corresponding to a predetermined pre-life.
At this time, the specified number of rotations during the pre-life period is set as the number of rotations corresponding to the period when it is predicted that the collection efficiency of the filter will decrease by about 10% from the initial value, for example, referring to the results of actual measurements such as experiments. be done.
At this time, the pre-life determination is made by detecting that the number of rotations of the second air blowing means 64 has reached a specified number of rotations. In addition, regarding the determination of whether the pre-life has been reached, for example, it is detected that the number of rotations of the first air blowing means 62 and the number of rotations of the second air blowing means 64 have reached respective specified number of rotations, which are separately determined. It may be configured to be performed by

Furthermore, in this collection device 6, the collection efficiency of the filter, which is the collection means 63, begins to decrease after the control timing of the silent/low-power collection mode. As shown in Fig. 1, both the first air blowing means 62 and the second air blowing means 64 are controlled to operate while their rotation speed is increased so as to compensate for the decrease in the collection efficiency of the filter. collection mode” is executed.
As shown in FIG. 9, the collection mode during the pre-life ends when the filter, which is the collection means 63, reaches the provisional life.
The collection device 6 is controlled in this pre-life collection mode, thereby appropriately collecting fine particles while compensating for the reduction in the collection efficiency of the filter, which is the collection means 63 .

The arrival of the provisional service life of the filter is detected by a filter pre-service life and provisional service life detection section 78 in the control means 70 . In this case, as shown in the upper part of FIG. 9, the detection by the arrival detection unit 78 is performed by detecting when the number of revolutions of the air blowing means reaches a specified number of revolutions corresponding to a predetermined provisional life.
At this time, the specified number of revolutions during the provisional service life is set as the number of revolutions corresponding to the period when the collection efficiency of the filter is expected to decrease by about 20% from the initial value, for example, referring to the results of actual measurements such as experiments. be done.
Also, determination of reaching the provisional life at this time is performed in the same manner as determination of reaching of the pre-life.

Finally, in the collecting device 6, when the collection mode control period during the pre-life period has passed, the collection efficiency of the filter, which is the collection means 63, is further reduced and the filter approaches its original life. Therefore, both the first air blowing means 62 and the second air blowing means 64 are rotated in a range of relatively high values so as to further compensate for the decrease in the collection efficiency of the filter as shown in FIG. A form of "end-of-life collection mode" that controls operation to maintain the number is implemented.
Also, the trapping mode just before the life of the filter ends at the time when the trapping efficiency of the filter reaches zero, as shown in FIG.
The collection device 6 is controlled in the collection mode just before the end of life, thereby further compensating for the reduction in the collection efficiency of the filter, which is the collection means 63, until the filter reaches its original life. done.

Incidentally, in the collection device 6, for example, when the filter serving as the collection means 63 reaches the end of its provisional life, a warning prompting replacement of the collection means 63 is displayed on the operation means 12 of the image forming apparatus 1 or the like. can be configured as

[Modification]
The present invention is in no way limited to the contents exemplified in the first embodiment, and various modifications are possible, including, for example, the following modifications.

Regarding the particulate collector 6, if it is possible to maintain at least the relationship "P2<P1≦atmospheric pressure" during its operation, the vent pipe 61 (including the flow path space 60) may be of another form. Or, applying a blowing means other than an axial fan as the first blowing means 62, applying a blowing means other than a sirocco fan as the second blowing means 64, or applying a collecting means 63 A collection device configured by applying another filter as a filter may be used.
Also, the operation (including the control operation) of the collection device 6 is not limited to the operation example illustrated in the first embodiment, and a configuration in which other operations are performed may be employed.

Regarding the vent pipe 61, for example, it is a vent pipe having a shape of a first flow passage space 60A that has the same width as the length of the collection means 63 in the longitudinal direction C and that extends substantially linearly to the first air blowing means 62. good too. Also, the vent pipe 61 may be a vent pipe that does not have the front channel space portion 60C. Further, with respect to the vent pipe 61, the inner wall surface facing the collecting means 63 in the longitudinal direction C of the collecting means 63 as the front channel space portion 60C is the same from the collecting means 63 in the entire area in the longitudinal direction C. It may be configured as a vent pipe having a front flow passage space portion of a structure separated by a distance.

12 and 13, in the collecting device 6, the end port 641c in the exhaust passage portion 641b of the sirocco fan, which is the second air blowing means 64 arranged on the upper surface portion 61Ba of the ventilation pipe 61, and the exhaust gas passage portion 641b. An opening 80 may be provided between the guiding means 69a.

As illustrated in FIG. 13 , this opening 80 allows the collection device 6 (the second blower 64 in the upper part of the vent pipe 61 and its exhaust passage) to be separated from the inside of the housing 10 of the image forming apparatus 1 . It is preferable to provide it when it is arranged adjacent to the space portion 18 . In this case, as will be described later, it is possible to obtain the function of easily exhausting the air in the adjacent space portion 18, which is effective. Reference numerals 18a and 18b in FIG. 13 and the like indicate partition walls. The adjacent space portion 18 is, for example, a space portion in which heat-generating components are arranged.
13, the opening 80 faces the flow path portion of the air (E5) flowing with directivity, for example, and faces the air flow (airflow). It must be provided in such a way that it can be touched. Moreover, in the opening 80, there is no passage shape portion or other parts that obstruct or change the flow of the air (E5) between the end port 641c of the exhaust passage portion 641b and the opening 80. must also not exist.

The opening 80 shown in FIG. 12 and the like is formed as a rectangular opening elongated in the vertical direction along the gravity direction between the terminal end 641c of the exhaust passage portion 641b and one end of the exhaust guide means 69a.
In addition, as shown in FIG. 13, the opening 80 has an inner wall surface 69ac of the plate-like member that is the exhaust guide means 69a shifted outward from the inner wall 641cd at the terminal end 641c of the exhaust passage portion 641b. It is formed to exist between the exhaust guide means 69a and the end port 641c of the exhaust passage portion 641b.
Furthermore, this opening 80 is formed as an opening facing in a direction substantially orthogonal to the direction of exhaust at the terminal end 641c of the exhaust passage 641b of the sirocco fan.

In the image forming apparatus 1 provided with the collecting device 6 having the opening 80, when the collecting device 6 starts and the sirocco fan, which is the second air blowing means 64, operates, as shown in FIG. 13 and FIG. The air discharged from the sirocco fan passes through the exhaust passage portion 641b and passes through the exhaust passage surrounded by the upper surface portion 61Ba of the air pipe 61 and the exhaust guide means 69a and 69b from the terminal port 641c. It flows as air E5 having directivity substantially along the direction. The air E5 at this time is finally exhausted to the outside from the exhaust port 13 (FIG. 5) of the housing 10. FIG.
At this time, in the opening 80, as shown in FIG. 14, the second air blowing means 64 above the ventilation pipe 61 of the collection device 6 and the other space adjacent to the exhaust passage in the housing 10 The air E11 existing in 18 is sucked so as to be attracted to the air flow of the air E5 flowing through the exhaust passage across the opening 80 .

As a result, as shown in FIG. 14, the air E11 existing in the adjacent space portion 18 enters the exhaust passage surrounded by the upper surface portion 61Ba of the vent pipe 61 and the exhaust guide means 69a, 69b through the opening 80. After that, it is multiplied by the airflow of the air E5 in the exhaust passage and flows along the inner wall surface 69ac of the exhaust guide means 69a as the air E12. exhausted to
As a result, when the air E11 existing in the adjacent space portion 18 contains excess heat, the air E11 containing the heat can be easily exhausted without providing countermeasure equipment such as a dedicated exhaust device. becomes possible.

In the first embodiment, the fine particle collection device 6 is applied as a collection device for collecting fine particles generated by the fixing means 5 of the image forming apparatus 1. However, the collection device 6 is It is also possible to apply it as a collecting device for collecting fine particles generated from components other than the fixing means 5 of the forming apparatus 1 . Furthermore, the collection device 6 can be applied to various devices other than the image forming device if collection of fine particles is required.

In addition, the image forming apparatus to which the fine particle collecting device 6 is applied is not limited to the type illustrated in the first embodiment, and may be an image forming apparatus of another type using an electrophotographic method. . Furthermore, the image forming apparatus to which the collection device 6 is applied may be an image forming apparatus that employs an image forming method other than the electrophotographic method (for example, a droplet jetting method, a printing method, etc.).

REFERENCE SIGNS LIST 1 ... image forming apparatus 5 ... fixing means 6 ... particle collecting device 9 ... paper (an example of a recording medium)
60 Flow path space 60A First flow path space 60B Second flow path space 60C Front flow path space portion 60Ca First space portion 60Cb Second space portion 61 Air pipe 62 First air blowing means 63 Collecting means 64 Second air blowing means 66 Inlet 67 Outlet C Longitudinal direction H1, H2 of collecting means Spacing distance P1 First pressure P2 Second pressure

Claims (6)

a vent pipe having a channel space for flowing air;
a first air blowing means for sending air containing fine particles into the channel space on one end side of the vent pipe;
a collecting means arranged in a flow channel space in the middle of the vent pipe in a state of blocking the flow channel and collecting fine particles contained in the air sent by the first air blowing means;
a second air blowing means for collecting air passing through the collecting means on the other end side of the ventilation pipe and sending the air out of the flow path space;
with
The vent pipe extends from the first flow passage space from the first air blowing means to the collection means in the flow passage space, and from the collection means to the second air blow means in the flow passage space. a second flow path space up to, a front flow path space portion existing along the longitudinal direction of the collection means at a position on the front side of the collection means in the first flow path space, and the front flow having an inlet through which air flows into the channel space portion, and an outlet through which the air in the second channel space that has passed through the collecting means is discharged to the second air blowing means;
The inflow port and the outflow port are arranged so as to exist at different end sides in the longitudinal direction of the collection means,
The front channel space portion has a first space portion on the side where the inflow port exists and a second space portion on the side where the inflow port does not exist, and faces the collecting means in the second space portion. The distance between the inner wall surface portion and the collecting means is smaller than the distance between the inner wall surface portion facing the collecting means and the collecting means in the first space portion,
The first air blowing means and the second air blowing means are arranged such that the pressure (P1) in the first flow path space and the pressure (P2) in the second flow path space satisfy the relationship of "P2<P1≦atmospheric pressure". A particulate trap that operates in a retained manner. The first air blowing means and the second air blowing means operate with the air volume (Q1) of the first air blowing means and the air volume (Q2) of the second air blowing means being maintained in a relationship of "Q1<Q2". 1. The collection device according to 1. 3. The collecting device according to claim 1, wherein said first air blowing means is an axial fan . 4. The collecting device according to any one of claims 1 to 3, wherein said second air blowing means is a sirocco fan . An image forming apparatus comprising the fine particle collecting device according to any one of claims 1 to 4 . A fixing means for fixing the unfixed image by passing through a recording medium holding the unfixed image;
6. The image forming apparatus according to claim 5, wherein the collecting device is arranged such that one end of the ventilation pipe on the side where the first blowing device is arranged is connected to the fixing device.

Images