JP2010117666A - Blade for oa - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blade for OA made by providing seal members adjoining on both sides of an elastic member, which reliably prevents leakage of a developing agent. <P>SOLUTION: In this blade 1 for OA, the elastic member 3 abutting against a body to be made contact is provided along the longitudinal direction LD, and seal members are provided adjoining both sides in the longitudinal direction of the elastic member. The elastic member includes a protruding part PR which protrudes to the seal members from the side face SF opposing to the seal members and extends in the thickness direction ZD. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an OA blade in which an elastic member made of a rubber material or the like is bonded to one side of a plate made of a long thin metal plate or the like.

  In electrophotographic or electrostatic recording type image forming apparatuses such as copying machines, facsimiles, and printers (hereinafter collectively referred to as “OA apparatuses”), a developer is carried on the outer periphery of a developing roller and rotated. In addition to the developing blade for regulating the amount of developer supplied by the developing roller, various blades such as a cleaning blade and a transfer blade for cleaning the photosensitive drum or belt are employed. These blades are referred to as OA blades and will be described below.

  As the OA blade, for example, a long metal plate made of a rubber member having sufficient flexibility to form a gap through which the developer passes and characteristics necessary for frictionally charging the developer. The thing of the form adhere | attached along the longitudinal direction is employ | adopted widely.

  For such an OA blade that regulates the amount of developer, for example, a metal plate pre-applied with an adhesive is set at a predetermined position in a mold, and the material is molded using a transfer molding method or an injection molding method. A manufacturing method is employed in which a metal member such as silicone rubber is bonded to a metal plate in a mold. Here, the rubber member is brought into contact (contacted) with the developing roller to regulate the amount of developer transport so that a uniform developer (toner) is formed on the developing roller.

In the OA blade as described above, the rubber member that contacts the developer as described above is pasted along the longitudinal direction on the plate corresponding to the development region, but a part of the regulated developer is OA. If a state of wrapping around the back side of the blade for the developer (downstream side in the developer flow direction) (hereinafter referred to as “developer leakage”) occurs, the developed image is deteriorated or contaminated by the developer. Causes wastefulness. Accordingly, various techniques for preventing leakage of the developer have been proposed as techniques related to the OA apparatus.
For example, Patent Document 1 proposes a developing device in which the distance L1 between the center of the supply roller and the OA blade tip is set smaller than the minimum distance L2 between the center of the supply roller and the peripheral wall of the developing housing. Further, the developing device is provided with a sealing material between the housing and the OA blade, and the tip position of the sealing material is preferably set so as to be between the distance L1 and the minimum distance L2. This prevents the developer from being compressed near the OA blade and prevents the developer from leaking to the back of the blade.
JP 2004-205733 A

  In Patent Document 1 described above, the developer stays in a compacted state in a space such as a contact portion between the developing roller and the supply roller, and accordingly, the developer leaks to the back side of the blade. So we have proposed a technology to deal with this. However, the technique of Patent Document 1 does not consider the leakage of the developer that occurs at both ends of the rubber member of the plate, and there is room to consider this. The leakage of the developer that occurs at both ends of the rubber member that regulates the developer will be described with reference to the drawings.

FIG. 10 is a diagram illustrating two (a) and (b) as a conventional configuration example in the case where a sealing material is provided on a plate of an OA blade. In each drawing, an external perspective view in which a CY portion in a circle indicated by a broken line is enlarged is shown below each.
Each of the OA blades BL shown here has a rubber member RA bonded to the central portion of the long plate PL along the longitudinal direction LD, and the length of the rubber member RA is within a range that regulates the developer. It is set according to. The difference between the blades for OA in (a) and (b) is the shape of the rubber member RA, which is appropriately designed according to the request of the OA device. In the case of (a), the rubber member RA has notches HG at both ends, and the front surface is formed as a curved surface along the developer flow direction CD. On the other hand, in the case of (b), the rubber member RA has a simple rectangular parallelepiped shape, and is formed with an edge raised with respect to the developer flow direction CD.

  When assembling an OA blade as shown in FIGS. 10A and 10B in a cartridge for an OA apparatus, seal members SE formed of urethane foam or the like are attached to both ends as shown in the figure. It is done. The reason why the seal member SE is affixed in this way is to prevent the developer from leaking from the end of the developing roller in the back of the OA blade or the developing roller.

However, the sticking of the seal member SE is often a manual operation, and the sticking position is likely to be displaced. In this way, when a positional deviation occurs in the seal member SE provided to stop the developer on both sides of the rubber member RA, an unacceptable gap SP is formed between the rubber member RA and the seal member SE, and the blade On the back side and the developing roller, the developer leaks out from the end of the developing roller. As a result, the above-described problem becomes apparent.
In addition, although it is possible to automate the sticking operation of the seal member SE with high accuracy, the cost increases due to the development of the sticking device and its manufacture. Moreover, since the material employ | adopted may differ between the rubber member and sealing member which are arrange | positioned adjacently, it is difficult to block | close the clearance gap produced between these reliably.

  Accordingly, an object of the present invention is to propose an OA blade in which a seal member is provided adjacent to both sides of an elastic member, and which can reliably prevent developer leakage.

  The object is to provide, on a long plate, an elastic member that is in contact with a contacted body along the longitudinal direction, and seal members are provided adjacent to both sides in the longitudinal direction of the elastic member. In the OA blade, the elastic member includes a protruding portion that protrudes from the side surface facing the seal member toward the seal member and extends in the thickness direction. Can be achieved.

  Moreover, it is preferable that the protruding portion has a structure provided over at least the entire thickness of the elastic member. Further, it is preferable that the protruding portion is formed continuously on the front surface of the elastic member facing in the developer flow direction. Further, it is preferable that the protruding portion has a structure formed so as to extend in a direction perpendicular to the upper surface of the plate. Moreover, it is preferable that the protruding portion has a structure that is longer than the thickness of the main body of the elastic member in the thickness direction. And it is good also as a structure where the said protrusion part is formed in multiple numbers.

  And it is preferable that the said protrusion part is further equipped with the additional part extended along the edge by the side of the upper surface of the said elastic member. The OA blade as described above can be formed as a developing blade as a preferred example.

  In the blade for OA according to the present invention, the elastic member provided on the plate includes the protruding portions protruding toward the sealing members on both sides, so that the developer enters the gap between the elastic member and the sealing member and the back side In addition, in the developing roller, it is possible to reliably prevent the developer from leaking out from the end of the developing roller, that is, the developer leakage. Such an OA blade can be manufactured in the same manner as in the past by simply changing the mold for manufacturing the blade. Therefore, the present invention can be easily executed. Therefore, the OA apparatus that employs the blade for OA of the present invention is an apparatus that forms a high-precision and high-definition image without the deterioration of the developed image due to the leakage of the developer and the contamination and waste due to the developer.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings. In the following embodiments, a developing blade will be described as an example, but applicable OA blades are not limited to this.
FIG. 1 is a diagram schematically showing a state where an OA blade is attached to an OA apparatus. FIG. 2 is a plan view showing the OA blade according to the present embodiment.

  The OA blade 1 includes a metal plate 2 as a thin and long plate, and a rubber member 3 as an elastic member disposed on a part of one surface 2a thereof. As such a rubber member 3, for example, a thermosetting rubber material such as a two-component curable polyurethane, fluororubber, chloroprene rubber, or liquid silicone rubber can be preferably used, but the productivity is excellent. In view of this, it is desirable to use liquid silicone rubber.

  The metal plate 2 can be formed of, for example, stainless steel. The rubber member 3 is bonded and fixed with an adhesive along the longitudinal direction LD of the metal plate 2. More specifically, the length of the rubber member 3 in the longitudinal direction LD is set according to the development area, and blank areas BA are provided on both sides thereof. Therefore, the basic form of the OA blade 1 is a state in which the rubber member 3 is bonded to the central portion between the blank areas BA on both sides. The blank areas BA on both sides are secured as areas for attaching a seal member for preventing leakage of the developer when assembled in the cartridge.

  As shown in FIG. 1, the OA blade 1 is disposed in a posture to contact (contact) the peripheral surface of the rotating developing roller 100 and regulate the layer thickness of the developer 101 on the developing roller peripheral surface 100 a. To function.

3 is a perspective view of the OA blade 1 shown in detail by partially enlarging the structure viewed in the direction of arrow X in FIG. The rubber member 3 includes projecting portions PR projecting toward the outer blank area BA on the side surfaces SF on both sides. The OA blade 1 according to the present invention effectively prevents the developer leakage described above by providing the rubber member 3 with the protruding portion PR outward from the side surface SF.
As described above, the seal member is attached to the blank area BA in the longitudinal direction LD. Here, if the rubber member 3 includes the protruding portion PR that is outward in the longitudinal direction LD, the protruding portion PR can be in contact with the sealing member when the sealing member is disposed adjacently later. . Thus, even if a gap is generated between the rubber member 3 and the seal member, the developer can be prevented from leaking by closing the gap.

  The OA blade 1 as shown in FIG. 3 uses a metal plate manufactured to a predetermined size (for example, vertical and horizontal dimensions of B5 to A3 size paper). Then, on such a metal plate, for example, a rubber member 3 having a length direction LD of about 210 to 250 mm, a thickness direction ZD of about 1.0 to 3.0 mm, and a width direction WD of about 4.0 to 9.0 mm. Is glued. The protrusion PR provided on the rubber member 3 is formed so as to have a length capable of contacting the seal member 4 disposed adjacent to the seal member 4 with a certain degree of contact pressure and closing the gap SP as a whole. Is desirable. For this purpose, it is desirable that the protruding portion PR is provided over the entire region (total thickness) in the thickness direction ZD of the rubber member 3. Therefore, the protruding portion PR needs to extend in the thickness direction of the rubber member 3, and more preferably extends in a direction perpendicular to the upper surface of the metal plate 2.

  For example, as shown in FIG. 3, the protruding portion PR has a shape like a triangular prism laid. In this case, for example, the height (length in the longitudinal direction LD) HL is about 5 to 500 μm, and the base side. The width of the base end portion (length in the width direction WD) WL is about 10 to 500 μm.

FIGS. 4A to 4D are diagrams collectively showing arrangement examples of the protrusions PR formed on the rubber member 3 with respect to the OA blade 1. In FIG. 4, a state in which the above-described seal member 4 is attached to a predetermined position of the blank area BA of the metal plate 2 is illustrated by a broken line, and a gap SP formed between the side surface of the rubber member 3 and the seal member 4 is illustrated. Shows a state in which the projection PR is closed.
First, FIG. 4A shows a case where the protrusion PR is continuously formed on the front surface FF of the main body of the rubber member 3 with respect to the developer flow direction CD. FIG. 4A is the same as the structure shown in FIG. Moreover, although the structure of the rubber member 3 in which the notch HG is formed at the end is illustrated here, the notch HG is not an essential structure in the present invention. A shape in which the front surface of the entire rubber member 3 is located at the same position in the width direction without providing the notch HG may be used.

  FIG. 4B is a structural example in which the projecting portion PR is arranged in the middle of the side surface SF in the width direction WD. Providing the protrusion PR so as to coincide with the front surface FF in the developer flow direction CD as in (a) is effective for preventing leakage of the developer, but in the middle of the gap SP as illustrated in (b). The developer may be prevented from leaking. In (a) and (b), the projecting portion PR is provided over the entire thickness in the thickness direction ZD.

  Further, FIG. 4C shows a case where the protruding portion PR is longer in the thickness direction ZD than the main body of the rubber member 3, that is, the protruding portion PR protrudes upward. By adopting such a structure, it is possible to prevent the developer from leaking by dealing with the situation where the developer blocked by the projecting portion PR then jumps over the projecting portion PR and turns to the back surface. This (c) is an improvement example of the structure shown in (a), but it can also be applied to the structure shown in (b).

  FIG. 4D shows a case where a thin tongue-shaped additional portion PRa extending along the upper edge of the rubber member 3 is provided at one end of the protruding portion PR. The additional portion PRa is preferably arranged so as to extend parallel to the upper surface TF of the rubber member 3 and cover the upper portion of the gap SP. By adopting such a structure, it is possible to prevent the developer blocked by the projecting part PR from jumping over the projecting part PR and entering the back gap SP, thereby preventing the developer from leaking. This (d) is an example of improvement of the structure shown in (b), but can also be applied to the structure shown in (a).

3 and 4 exemplify a case where the cross-sectional shape of the protruding portion PR of the rubber member 3 is a triangular prism shape, but is not limited thereto. As shown in FIG. 5, it is good also as columnar shape whose cross section is arch shape.
3 and 4 exemplify the case where one protrusion PR that the rubber member 3 has is provided, the present invention is not limited to this. As shown in FIG. 6, the rubber member 3 may have a structure in which a plurality of protrusions PR are formed in the width direction WD, for example.

  The OA blade 1 as described above has the protruding portions PR in which the rubber member 3 provided on the metal plate 2 protrudes toward the sealing member 4 on both sides, and therefore the rubber member 3 and the sealing member 4. It is possible to reliably prevent the developer from entering the gap SP and wrapping around to the back side, that is, the leakage of the developer.

The OA blade 1 described above can be manufactured using a mold in the same manner as a conventional blade. A preferred method for manufacturing the OA blade 1 will be further described with reference to the drawings.
FIG. 7 is a plan view schematically showing the structure of the lower mold 10 which is one of the molds used when manufacturing the OA blade 1. FIG. 8 is a side view showing the entire structure of the mold 5 having the lower mold 10 and the upper mold 15 shown in FIG. The upper die 15 has a shape corresponding to the lower die 10, and when set on the lower die 10, a shape corresponding to the OA blade 1 is formed therein.

  The lower mold 10 illustrated in FIG. 7 is designed so that a plurality of OA blades 1 (see FIG. 2) can be manufactured simultaneously. The lower mold 10 is designed to take a plurality (four in the illustration of FIG. 7). In FIG. 7, four cavities CA-1 to CA-4 are formed in the lower mold 10 so as to simultaneously manufacture four OA blades. In the manufacturing process, the metal plate 2 (see FIG. 2) is set at a predetermined position of the lower mold 10, filled with the material in each of the cavities CA-1 to CA-4, and cured, whereby the rubber member 3 is positioned at the predetermined position. The blade 1 for OA prepared for can be manufactured. In FIG. 7, reference numeral 14 corresponds to the position of a gate (injection port) for supplying material into the cavity CA-1.

  The OA blade mold 5 is the same as the conventional mold in that the lower mold 10 and the upper mold 15 are configured as described above, but includes the rubber member 3 having the above-described protrusion PR. Some changes have been made so that OA blades can be manufactured. Specifically, a hollow portion protruding outward is provided on the inner side wall (cavity surface) of each of the cavities CA-1 to CA-4. By setting this recess, the rubber member 3 having the protrusion PR can be formed as described above. As described above, the above-described protrusion PR can be formed only by making a simple change to a part of the mold used in the prior art. Since the four cavities CA formed in the mold are the same, the first cavity CA-1 will be described as an example.

  FIG. 9 is an enlarged view of the LE portion at the left end of the first cavity CA-1 shown in FIG. However, FIG. 9 shows a case where two blocks RK-1 and RK-2 are fitted adjacent to the cavity CA-1, and a depression CR is formed in the block RK-1. The outer shape of the rubber member 3 is defined by a cavity provided in the mold. An outwardly recessed portion CR is formed at the position of the side surface of the cavity where the protrusion PR is to be formed on the rubber member 3. More specifically, one block RK-1 is formed by notching a portion corresponding to the depression CR, and the opening MU of the depression CR faces the cavity CA-1. Therefore, by providing an opening corresponding to the opening MU in the cavity CA-1, the cavity CA-1 and the depression CR are continuous.

Note that the opening MU needs to be set to a size (large) so that at least the material can be smoothly poured into the depression CR according to the properties of the rubber material to be employed. For example, liquid silicone is adopted as the material, mold temperature 160 to 180 (° C.), filling pressure 20 to 80 MPa, filling time 0.5 to 3.0 (s), material viscosity 100 to 800 Pa · s (10 s ^−1). ) In the case where it is fed as a degree, the opening size is set to 10 to 500 μm, for example. This opening dimension corresponds to the dimension of the width WL with respect to the base of the protrusion PR.

  The structure applied to the mold 5 will be described again with reference to FIG. The upper die 15 of the mold 5 is formed with runner portions 23 and 24 for receiving the material MA supplied from the injection nozzle 40 through the sprue 41 and sending it to the cavity CA of the lower die 10. These runner portions 23 and 24 are combined to form a cold runner. Here, the outlet 24a at the lower end of the runner portion 24 extending in the vertical direction is connected to the gate 14 described above for injecting material into the cavity CA. The material is filled into the cavities CA-1 to CA-4 of the lower mold 10 through openings provided in the metal plate 2.

  It is desirable to provide the mold 5 with a cold runner structure for cooling the material as necessary so that a thermosetting material such as liquid silicone can be reliably injected into each cavity CA. This cold runner structure is applied to the cold runners 23 and 24 as described later.

  As shown in FIG. 8, a part of the runner portion 24 is surrounded by a cooling jacket 26 and is configured as a cold runner that can be cooled. That is, the runner portion 24 forming the cylindrical space is in contact with the cylindrical cooling jacket 26 via the bush 25 forming the cylindrical space, and the cooling jacket 26 passes a cooling medium, for example, cooling water. 27, the runner portion 24 provided in the cylinder of the cooling jacket 26 is cooled by guiding the cooling medium to the cooling pipe 27 and passing therethrough, and the material MA such as liquid silicone passing through the cooling medium 26 is passed through. It is kept at a temperature at which curing is difficult to proceed so as not to be cured. In FIG. 8, PL is a parting line, the upper die 15 is the upper die 15 and the lower die 10 is the lower die.

  Around the cavity CA of the lower mold 10, a heater 32 for curing the thermosetting material MA injected into the cavity CA is provided not only on the lower mold 10 but also on the lower side of the upper mold 15. On the other hand, even if the material MA stays in the runner portions 23 and 24, the upper mold 15 is provided with a cooling pipe 31 so as not to be cured. The cooling pipe 31 cools the entire upper side of the upper mold 15 separately from the cold runner structure around the runner portion 24. In the middle of the upper mold 15, heat insulating layers 28 and 29 are arranged as a preferable structure for increasing the thermal efficiency.

  Further, a structure that the mold 5 preferably has will be described with reference to FIG. The lower mold 10 is provided with a sealing packing 17 around the cavities CA-1 to CA-4, and a vacuum pulling portion 18 is provided inside the packing 17 (through the packing in FIG. 6). ing. The evacuation unit 18 is connected to an external gas suction device 19 so as to evacuate the periphery of the cavity in the packing 17. If the structure for vacuuming is further provided in this way, the periphery of the cavity can be adjusted to a low pressure, so that the rubber member having the projecting portion PR can be reliably formed by smoothly flowing the material into the recessed portion CR.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

  As is apparent from the above description, according to the present invention, an OA blade capable of reliably preventing developer leakage can be provided. An OA apparatus that employs such an OA blade can accurately form a high-precision and high-definition image by regulating the developer.

It is a figure which shows typically a mode when the blade for OA is attached to the OA apparatus. It is the top view shown about the blade for OA concerning this embodiment. FIG. 3 is a perspective view of the OA blade shown in detail by partially enlarging the structure seen in the direction of arrow X in FIG. 2. (A)-(d) is the figure which showed collectively the example of arrangement | positioning of the protrusion part formed in a rubber member about the blade for OA. It is a figure shown about other shape examples of the projection part formed in a rubber member. It is a figure shown about the example which provides multiple protrusion parts formed in a rubber member. It is the top view which showed typically the structure of the upper mold | type which is one side of the metal mold | die used when manufacturing the braid | blade for OA. It is the side block diagram which showed the whole structure of the metal mold | die provided with the upper mold | type and lower mold | type shown in FIG. It is the figure which expanded the LE part of the left end part of the cavity shown in FIG. It is the figure shown in order to demonstrate the conventional structure in the case of arrange | positioning a sealing material to the plate of the blade for OA.

Explanation of symbols

1 Blade for OA 2 Metal plate (plate)
3 Rubber member (elastic member)
4 Seal member 5 Mold 100 Developing roller (contacted body)
CA cavity LD Longitudinal direction WD Width direction ZD Thickness direction PR Protrusion SF Side FF Front

Claims (8)

An OA blade in which an elastic member that is in contact with a contacted body is provided along a longitudinal direction on a long plate, and a sealing member is provided adjacent to both sides in the longitudinal direction of the elastic member. In
The blade for OA, wherein the elastic member includes a protruding portion that protrudes from the side surface facing the seal member toward the seal member and extends in the thickness direction. The OA blade according to claim 1, wherein the protruding portion is provided over at least the entire thickness of the elastic member. 2. The OA blade according to claim 1, wherein the protruding portion is formed continuously on the front surface of the elastic member facing in the developer flow direction. The OA blade according to claim 1, wherein the protrusion is formed to extend in a direction perpendicular to the upper surface of the plate. 2. The OA blade according to claim 1, wherein the protruding portion is formed longer than a thickness of the main body of the elastic member in the thickness direction. The OA blade according to claim 1, wherein a plurality of the protruding portions are formed. 2. The OA blade according to claim 1, wherein the protruding portion further includes an additional portion extending along an edge on the upper surface side of the elastic member. The OA blade according to claim 1, wherein the blade is formed as a developing blade.

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