JP6003625B2 - Development device - Google Patents

Description

  The present invention relates to a developing device including a seal member for suppressing the leakage of developer from between a developing roller and a casing.

  Conventionally, as a developing device, a housing that accommodates toner, a developing roller that is disposed to face an opening formed in the housing, and a seal member that is disposed between an end of the developing roller and the housing The thing provided with (refer patent document 1) is known.

JP 2009-63635 A

  By the way, in the developing device described above, the rotating developing roller is brought into sliding contact with the seal member, and the sliding contact portion is heated by friction. For this reason, when the rotation speed of the developing roller is increased in order to increase the printing speed, the sliding contact portion becomes high in temperature, and the toner melts in the sliding contact portion, so that toner leakage may occur.

  SUMMARY An advantage of some aspects of the invention is that it provides a developing device capable of releasing heat in a sliding contact portion between a developing roller and a seal member.

In order to achieve the above-described object, a developing device of the present invention includes a housing for containing a developer, a developing roller disposed in an opening formed in the housing, and between the developing roller and the housing. In order to suppress the leakage of the developer, a seal member disposed between the developing roller and the housing, the plurality of fibers extending in the first direction and the plurality of fibers extending in the second direction A sealing member having a crossed fabric member; and a heat dissipating member for contacting the sealing member to dissipate heat of the sealing member.
The fiber of the fabric member has a peripheral surface where the heat dissipation amount per unit area is the first heat dissipation amount, and an end surface where the heat dissipation amount per unit area is a second heat dissipation amount larger than the first heat dissipation amount, The fabric member has a first surface facing the developing roller and a second surface opposite to the first surface.
And the textile member is cut | disconnected by the heat radiating member from at least one side of the 1st surface and the 2nd surface, leaving a part, and the cut surface of a fiber and the heat radiating member are contacting.

  According to such a configuration, since the heat radiating member is brought into contact with the seal member, the heat generated at the sliding contact portion between the developing roller and the seal member can be released via the heat radiating member. Further, by cutting the fabric member with the heat radiating member, the cut surface (end surface) of the fiber and the heat radiating member can be brought into contact with each other. The heat transmitted to the fibers can be efficiently released to the heat radiating member. Furthermore, since the fabric member is cut by leaving a part with the heat radiating member, it is possible to suppress the heat radiating member from being separated from the cut surface of the fiber as compared with a configuration in which the fabric member is completely cut.

  In the above-described configuration, the fabric member may be cut from both sides of the first surface and the second surface leaving a part.

  According to such a structure, a heat radiating member can be made to contact the cut surface of a fiber in the both sides of the 1st surface and 2nd surface of a textile fabric member.

  In the above-described configuration, the heat dissipating member may be disposed at a position other than the portion of the fabric member that faces the developing roller.

  According to such a configuration, since the heat dissipating member is disposed at a position other than the portion of the fabric member facing the developing roller, the development is compared with the configuration in which the heat dissipating member is disposed at the portion facing the developing roller. It can suppress that a roller and a thermal radiation member contact.

  In the above-described configuration, the heat dissipation member may have a protrusion for cutting the fiber.

  According to such a configuration, the fibers can be easily cut by the protrusions of the heat dissipation member.

  In the configuration described above, the heat dissipation member may be formed of metal.

  According to the present invention, heat in the sliding contact portion between the developing roller and the seal member can be released.

1 is a cross-sectional view illustrating a laser printer including a developing cartridge according to an embodiment of the present invention. FIG. 3 is a cross-sectional view showing a developing cartridge. It is a perspective view which shows the structure around the opening of a housing | casing. It is a disassembled perspective view which shows a side seal member simply. It is sectional drawing (a) which shows the state with which the side seal member was attached to the housing | casing, and (b) which shows that the cut surface and protrusion of a vertical fiber are contacting. FIG. 6A is a diagram showing the periphery of the protrusion corresponding to FIG. 5A in the first modification, and FIG. 6B is a diagram showing the periphery of the protrusion corresponding to FIG. 5A in the second modification. It is an enlarged view which shows the heat radiating member periphery which concerns on a 3rd modification.

  Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, the overall configuration of the laser printer will be briefly described, and then the details of the features of the present invention will be described.

  Further, in the following explanation, explanation will be given in the direction based on the user when the laser printer 1 is used. That is, the right side in FIG. 1 is “front”, the left side is “rear”, the front side is “left”, and the back side is “right”. Also, the vertical direction in FIG.

  As shown in FIG. 1, the laser printer 1 includes a main body casing 2, a feeder unit 4 for feeding paper 3, and an image forming unit 5 for forming an image on the paper 3.

  The feeder unit 4 includes a paper feed tray 6 that is detachably attached to the bottom of the main casing 2 and a paper pressing plate 7 provided in the paper feed tray 6. The feeder unit 4 includes various rollers 11 that carry the paper 3 and remove paper dust. In the feeder unit 4, the sheet 3 in the sheet feeding tray 6 is moved upward by the sheet pressing plate 7 and conveyed to the image forming unit 5 by various rollers 11.

  The image forming unit 5 includes a scanner unit 16, a process cartridge 17, and a fixing unit 18.

  The scanner unit 16 is provided at an upper portion in the main body casing 2 and includes a laser light emitting unit (not shown), a polygon mirror 19 that is rotationally driven, lenses 20, 21 and reflecting mirrors 22, 23, 24, and the like. . In the scanner unit 16, the laser beam is irradiated on the surface of the photosensitive drum 27 by high-speed scanning through a path indicated by a chain line in the drawing.

  The process cartridge 17 can be attached to and detached from the main casing 2 by appropriately opening a front cover 2 a provided on the front side of the main casing 2. The process cartridge 17 includes a developing cartridge 28 as an example of a developing device and a drum unit 39.

  The developing cartridge 28 is detachably attached to the main casing 2 while being attached to the drum unit 39. The developing cartridge 28 may be configured to be detachable from the drum unit 39 fixed to the main casing 2. As shown in FIG. 2, the developing cartridge 28 includes a developing roller 31, a layer thickness regulating blade 32, a supply roller 33, and a toner storage chamber 34.

  In the developing cartridge 28, toner as an example of a developer stored in the toner storage chamber 34 is stirred by the agitator 34 </ b> A and then supplied to the developing roller 31 by the supply roller 33. The toner is positively frictionally charged with the developing roller 31. The toner supplied onto the developing roller 31 enters between the layer thickness regulating blade 32 and the developing roller 31 as the developing roller 31 rotates, and is regulated to a thin layer having a certain thickness while being frictionally charged. Then, it is carried on the developing roller 31. Details of the developing cartridge 28 will be described later.

  As shown in FIG. 1, the drum unit 39 includes a photosensitive drum 27, a scorotron charger 29, and a transfer roller 30. In the drum unit 39, the surface of the photosensitive drum 27 is uniformly positively charged by the scorotron charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 16. Thereby, the potential of the exposed part is lowered, and an electrostatic latent image based on the image data is formed.

  Next, by the rotation of the developing roller 31, the toner carried on the developing roller 31 is supplied to the electrostatic latent image formed on the surface of the photosensitive drum 27, so that the toner image is formed on the surface of the photosensitive drum 27. It is formed. Thereafter, the sheet 3 is conveyed between the photosensitive drum 27 and the transfer roller 30, whereby the toner image carried on the surface of the photosensitive drum 27 is transferred onto the sheet 3.

  The fixing unit 18 includes a heating roller 41 and a pressure roller 42 that is disposed to face the heating roller 41 and pressurizes the heating roller 41. In the fixing unit 18 configured as described above, the toner transferred onto the paper 3 is thermally fixed while the paper 3 passes between the heating roller 41 and the pressure roller 42. The sheet 3 thermally fixed by the fixing unit 18 is conveyed to a paper discharge roller 45 disposed on the downstream side of the fixing unit 18, and is sent out from the paper discharge roller 45 onto a paper discharge tray 46.

<Detailed structure of developing cartridge>
Next, the detailed structure of the developing cartridge 28 according to an embodiment of the present invention will be described. Since the developing cartridge 28 has a symmetrical structure, only one of the left and right parts is shown in FIG. 3 and the like, and the other part is omitted. 3 shows a state in which the developing roller 31, the supply roller 33, and an outer reinforcing plate 32C (see FIG. 2) to be described later are removed.

  As shown in FIG. 3, the developing cartridge 28 includes the developing roller 31 and the like described above, a housing 50 for storing toner, and a side seal as an example of a seal member that is in sliding contact with both ends of the developing roller 31. A member 61 and a lower film 63 are provided. The developing roller 31 is rotated in the direction of the arrow shown in the drawing, that is, so as to be in sliding contact with the lower film 63 and the side seal member 61 in this order.

  A bearing portion 51 that rotatably supports the developing roller 31, an opening 52 for supplying toner from the toner storage chamber 34 to the developing roller 31, and a side seal member 61 are attached to the housing 50. A side seal attaching surface 53 and a support portion 54 that supports the lower film 63 are formed. The opening 52 is formed in a rectangular long hole shape along the axial direction of the developing roller 31, and the layer thickness regulating blade 32 is fixed to the upper portion thereof.

  The layer thickness regulating blade 32 includes a plate-like metal plate 32A that is elongated in the left-right direction, and a rubber pressing member 32D that is fixed to the lower end portion (tip portion) of the metal plate 32A. The pressing member 32D is formed to have a smaller left-right width than the metal plate 32A. Further, both end portions in the left-right direction of the pressing member 32D are in contact with the fabric member 61B.

  As shown in FIG. 2, a pair of heat radiating members as an example of a heat radiating member that sandwiches and reinforces the upper end of the layer thickness regulating blade 32 (the end opposite to the end that contacts the developing roller 31). The reinforcing plates 32B and 32C are provided. The layer thickness regulating blade 32 and the pair of reinforcing plates 32B and 32C are fixed to the housing 50 via a known blade back seal 64. In other words, the outer reinforcing plate 32 </ b> C sandwiches and holds the layer thickness regulating blade 32, the inner reinforcing plate 32 </ b> B, and the blade back seal 64. The reinforcing plates 32B and 32C will be described in detail later.

  As shown in FIG. 3, the side seal attaching surface 53 is a substantially arc-shaped surface in cross section and is formed on both the left and right sides of the opening 52. A side seal member 61 is provided on the side seal attaching surface 53. The side seal member 61 will be described in detail later.

  The support portion 54 is formed so as to protrude from the side seal attaching surface 53 toward the developing roller 31 and to extend along the axial direction of the developing roller 31. A lower film 63 is provided on the upper surface of the support portion 54.

  The lower film 63 is a sheet-like member made of a resin such as polyethylene terephthalate, and extends along the axial direction of the developing roller 31 and is in sliding contact with substantially the entire developing roller 31. And this lower film 63 is formed in the left-right direction longer than the support part 54, and in the state affixed to the support part 54, the both ends protrude from the support part 54, and the side seal member 61 and They are arranged so as to overlap. Thereby, toner leakage between the side seal member 61 and the lower film 63 is suppressed.

  The side seal member 61 is a member for suppressing the leakage of toner from between the both end portions of the developing roller 31 disposed so as to face the opening 52 of the housing 50 and the side seal attaching surface 53. It is provided between both end portions of the roller 31 and the side seal attaching surface 53. As shown in FIGS. 4 and 5, the side seal member 61 includes a base material 61A having elasticity and a fabric member 61B laminated on the surface of the base material 61A on the developing roller 31 side. .

  The base 61A is formed of an elastic body such as an elastically deformable urethane sponge, and is attached to the side seal attaching surface 53 of the housing 50 by the double-sided tape T1 so as to be adjacent to the lower end of the blade back seal 64. Has been. In FIG. 5, illustration of the double-sided tapes T1 and T2 is omitted for convenience.

  The fabric member 61B is formed in a long sheet shape extending along the rotation direction of the developing roller 31, and intersects the plurality of longitudinal fibers B1 extending in the longitudinal direction and the transverse fibers B2 extending in the lateral direction. It is composed by weaving into. Further, the diameters of the fibers B1 and B2 of the fabric member 61B are about 150 μm for the longitudinal fibers B1 and about 200 μm for the transverse fibers B2. As the weaving method, twill weave and satin weave are preferable. Here, the longitudinal direction (the rotation direction of the developing roller 31) corresponds to an example of the first direction, and the short direction (the axial direction of the developing roller 31) corresponds to an example of the second direction.

  Specifically, a plurality of longitudinal fibers B1 are provided in the short direction of the fabric member 61B, and a plurality of longitudinal fibers B1 are also provided in the thickness direction of the fabric member 61B. A plurality of transverse fibers B2 are provided in the longitudinal direction of the fabric member 61B, and a plurality of transverse fibers B2 are also provided in the thickness direction of the fabric member 61B. Note that the fibers B1 and B2 are omitted as appropriate, for example, in FIG. 3 and FIG.

  And each fiber B1, B2 has a peripheral surface where the heat dissipation amount per unit area is the first heat dissipation amount, and an end face where the heat dissipation amount per unit area is a second heat dissipation amount larger than the first heat dissipation amount. Have. Specifically, as the fibers B1 and B2 having such properties, fibers having a molecular structure in which molecules are linearly arranged can be employed. For example, ultrahigh molecular weight polyethylene or PBO (polyparaffin). (Phenylene benzobisoxador) fiber or the like can be employed. More specifically, the thermal conductivity in the direction toward the end face at 100K is 0.1 W / cm · K to 1.0 W / cm · K, and 2 to 50 of the thermal conductivity in the circumferential direction. Fibers that are twice or more are preferred. In this embodiment, Dyneema (registered trademark) SK60 fiber manufactured by Toyobo Co., Ltd. was used.

  The fabric member 61B is formed so as to be longer than the base material 61A in the longitudinal direction, and is adhered to the base material 61A, the blade back seal 64, and the inner reinforcing plate 32B by a double-sided tape T2. The fabric member 61B has a first surface B3 facing the developing roller 31 and a second surface B4 opposite to the first surface B3, and the upper end of the first member B is a pair of reinforcing plates 32B and 32C. It is sandwiched.

  The pair of reinforcing plates 32B and 32C are made of metal, and are disposed at positions other than the portion of the fabric member 61B facing the developing roller 31. The reinforcing plates 32B and 32C are exposed to the outside of the housing 50, and have protrusions 32E and 32F that protrude toward the fabric member 61B on the surface sandwiching the fabric member 61B.

  The protrusions 32E and 32F are for cutting the longitudinal fibers B1 of the woven fabric member 61B, and are formed in a triangular shape in cross-sectional view with a sharp tip. The protrusions 32E and 32F extend from the right end to the left end of the fabric member 61B in the left-right direction, and are disposed at positions facing each other. The protrusions 32E and 32F may protrude outward in the left-right direction of the fabric member 61B. Further, the protrusions 32E and 32F are formed in such a size that the respective tip portions do not come into contact with each of the reinforcing plates 32B and 32C sandwiching the metal plate 32A. That is, the sum of the height of the protrusion 32E and the height of the protrusion 32F is smaller than the thickness of the metal plate 32A.

  Then, as the reinforcing plates 32B and 32C sandwich the upper end of the fabric member 61B, as shown in FIG. 5B, the fabric member 61B has projections from both sides of the first surface B3 and the second surface B4. Cut by 32E and 32F, leaving a part. With this configuration, the cut surface B10 (end surface) of each longitudinal fiber B1 is in contact with the protrusions 32E and 32F of the reinforcing plates 32B and 32C.

  Therefore, the heat generated at the sliding contact portion between the developing roller 31 and the fabric member 61B can be transmitted from the cut surface B10 of each longitudinal fiber B1 to each projection 32E, 32F, and therefore via each reinforcing plate 32B, 32C. It is possible to dissipate heat. The reinforcing plates 32B and 32C are also in contact with the flat surface of the fabric member 61B (the peripheral surface of the longitudinal fibers B1), and heat is radiated from here as well, but the heat dissipation amount per unit area is greater than the peripheral surface of the fibers. Since the end face of the fiber is larger, the heat dissipation efficiency is improved at the portion where the longitudinal fiber B1 is in contact with the protrusions 32E and 32F from the cut surface B10.

  In the developing cartridge 28 configured as described above, as shown in FIG. 3, when the developing roller 31 rotates, both end portions of the developing roller 31 and the surface on the developing roller 31 side of the fabric member 61B come into sliding contact. When heat is generated from the sliding contact portion between the developing roller 31 and the fabric member 61B, the heat is transmitted along each longitudinal fiber B1, and each reinforcing plate 32B is transmitted from the cut surface B10 of each longitudinal fiber B1. , 32C is efficiently transmitted to the protrusions 32E, 32F. Heat is also transmitted from the peripheral surface of the fiber to the reinforcing plates 32B and 32C.

  In addition, the heat radiating member is not contacting the lower end surface of the vertical fiber B1. Specifically, since it is in contact with air, the amount of heat released from the end face is small. Moreover, since the heat radiating member is not in contact with the end face of each horizontal fiber B2 (touching the air), the amount of heat released from the end face is small, and the heat of each horizontal fiber B2 is relatively low. It is transmitted to the fiber B1.

  The heat transmitted from the cut surface B10 of each longitudinal fiber B1 to the protrusions 32E and 32F of the reinforcing plates 32B and 32C is radiated to the outside of the housing 50 through the reinforcing plates 32B and 32C. Therefore, according to the present embodiment, the heat generated in the sliding contact portion between the developing roller 31 and the side seal member 61 can be released via the reinforcing plates 32B and 32C.

  Further, by cutting the fabric member 61B with the reinforcing plates 32B and 32C, the reinforcing plates 32B and 32C can be brought into contact with the cut surfaces B10 (end surfaces) of the longitudinal fibers B1, so that the plane of the fabric member 61B Compared with the structure in which the reinforcing plates 32B and 32C are brought into contact only with the (circumferential surface of the fiber), the heat transmitted to the vertical fibers B1 can be efficiently released to the reinforcing plates 32B and 32C. Furthermore, since the fabric member 61B is cut with the reinforcing plates 32B and 32C leaving a part, the reinforcing plates 32B and 32C are cut from the cut surfaces of the longitudinal fibers B1 as compared with the configuration in which the fabric member 61B is completely cut. The fabric member 61B can be held by the reinforcing plates 32B and 32C as it is.

  Further, since the fabric member 61B is cut leaving a part from both sides of the first surface B3 and the second surface B4, the reinforcing plates 32B are provided on both sides of the first surface B3 and the second surface B4 of the fabric member 61B. , 32C can be brought into contact with the cut surface B10 of each longitudinal fiber B1.

  Further, since the reinforcing plates 32B and 32C (heat radiating members) are arranged at positions other than the portion facing the developing roller 31 in the fabric member 61B, for example, the heat radiating members are arranged at the portions facing the developing roller 31. Compared with the structure to perform, it can suppress that the developing roller 31 and a heat radiating member contact.

  Further, since the reinforcing plates 32B and 32C have the protrusions 32E and 32F, the fibers can be easily cut by the protrusions 32E and 32F of the reinforcing plates 32B and 32C.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention. In the following description, components that are substantially the same as those in the above embodiment are given the same reference numerals and description thereof is omitted.

<First Modification>
In the embodiment, the protrusions 32E and 32F of the reinforcing plates 32B and 32C face each other. However, the present invention is not limited to this, and for example, as shown in FIG. , 32F may be arranged at positions that do not face each other. Even in such a configuration, the heat generated in the sliding contact portion between the developing roller 31 and the side seal member 61 is transmitted to the projections 32E and 32F from the cut surface of each longitudinal fiber, as in the above embodiment. Therefore, it is possible to efficiently dissipate heat through the reinforcing plates 32B and 32C.

<Second Modification>
In the above embodiment, the fabric member 61B is cut from both sides of the first surface B3 and the second surface B4 by the protrusions 32E and 32F, but from one side of the first surface B3 and the second surface B4. The configuration may be such that the fabric member 61B is cut while leaving a part. For example, as shown in FIG. 6B, the inner reinforcing plate 32B may have a protrusion 32E and the outer reinforcing plate 32C may have no protrusion. Even with such a configuration, the fabric member 61B can be cut from the second surface B4 side by the protrusion 32E while leaving a part of the fabric member 61B. Therefore, as in the above-described embodiment, the heat generated in the sliding contact portion between the developing roller 31 and the side seal member 61 can be transmitted from the cut surface of each vertical fiber to the protrusion 32E. It is possible to efficiently dissipate heat through 32B.

<Third Modification>
In the said embodiment, although a pair of reinforcement board 32B, 32C was used as a heat radiating member, this invention is not limited to this, You may use members other than each reinforcement board 32B, 32C as a heat radiating member.

For example, as shown in FIG. 7, a metal member 55 embedded in the housing 50 may be used as a heat dissipation member.
The metal member 55 is embedded in a part of the housing 50 where the side seal attaching surface 53 is formed by insert molding or the like, and the outer surface thereof is exposed to the outside of the housing 50. Further, the metal member 55 has a protrusion 55 </ b> A that protrudes from the side seal attaching surface 53 toward the developing roller 31.

  The protrusion 55 </ b> A is formed in a triangular shape in cross section with a sharp tip, and extends from the right end to the left end of the side seal member 61 in the left-right direction. The protrusion 55A is smaller than the thickness of the side seal member 61 and larger than the thickness of the base material 61A. By sticking the side seal member 61 to the side seal attaching surface 53, the protrusion 55A of the metal member 55 penetrates the base material 61A and cuts leaving a part of the fabric member 61B. Even in such a configuration, since the cut surface of the fabric member 61B and the protrusion 55A are in contact with each other, the sliding contact portion between the developing roller 31 and the side seal member 61 is generated as in the above embodiment. The heat that has been performed can be transmitted from the cut surface of each longitudinal fiber to the protrusion 55A. Therefore, the heat can be released to the outside of the housing 50 through the metal member 55.

  In each of the embodiments, the developing cartridge 28 integrally including the toner storage chamber 34 is illustrated as the developing device. However, the present invention is not limited to this, and the developing device can be attached and detached, for example, with a toner cartridge having the toner storage chamber. What is called a process cartridge provided with a developing device, a photosensitive drum, and a developing roller may be used.

  In each of the embodiments, the laser printer is exemplified as the image forming apparatus to which the developing device is attached. However, the present invention is not limited to this, and may be another image forming apparatus such as a color printer or a multifunction peripheral.

  In the above embodiment, the side seal member 61 has a two-layer structure, but the present invention is not limited to this, and may have a three-layer structure or more as long as it has a woven member. In addition, the seal member is not limited to the side seal member 61 as long as the seal member is in sliding contact with the developing roller. For example, when the seal member is provided instead of the lower film 63, the present invention is applied to the seal member. May be.

  In each said embodiment, although each member which comprises a heat radiating member was formed with the metal, this invention is not limited to this, For example, you may form with a heat conductive resin.

28 Developing Cartridge 31 Developing Roller 32B Reinforcement Plate 32C Reinforcement Plate 32E Protrusion 32F Protrusion 50 Housing 52 Opening 61 Side Seal Member 61B Textile Member B1 Longitudinal Fiber B3 First Surface B4 Second Surface B10 Cut Surface

Claims (5)

A housing for containing the developer;
A developing roller disposed in an opening formed in the housing;
A seal member disposed between the developing roller and the housing to prevent the developer from leaking between the developing roller and the housing, and a plurality of members extending in the first direction. A sealing member having a fabric member in which the fibers and a plurality of fibers extending in the second direction intersect;
A heat radiating member for contacting and dissipating heat of the seal member in contact with the seal member,
The fiber of the fabric member has a peripheral surface where the heat dissipation amount per unit area is the first heat dissipation amount, and an end surface where the heat dissipation amount per unit area is a second heat dissipation amount larger than the first heat dissipation amount. And
The fabric member has a first surface facing the developing roller and a second surface opposite to the first surface;
The fabric member is cut from the at least one side of the first surface and the second surface leaving a part by the heat dissipation member,
The developing device, wherein the cut surface of the fiber is in contact with the heat radiating member.   The developing device according to claim 1, wherein the fabric member is cut from both sides of the first surface and the second surface leaving a part.   The developing device according to claim 1, wherein the heat radiating member is disposed at a position other than a portion of the fabric member facing the developing roller.   The developing device according to claim 1, wherein the heat radiating member has a protrusion for cutting the fiber.   The developing device according to claim 1, wherein the heat radiating member is made of metal.

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