JP5399666B2 - Development blade mold, development blade produced thereby, and development blade production method - Google Patents

Description

  The present invention relates to a technique for manufacturing a developing blade in which an elastic member such as a rubber material is bonded to one surface of a hard plate formed of metal or the like. More specifically, the gold is suitable for manufacturing a developing blade in which a blank area where nothing is arranged on both sides in the longitudinal direction of a long hard plate is secured, and an elastic member to be brought into contact with the developer is bonded therebetween. Regarding type.

Non-magnetic developers are used for electrophotographic or electrostatic recording type image forming apparatuses such as copying machines, facsimile machines, printers, etc. (hereinafter collectively referred to as “OA apparatuses”), particularly for color. A system is adopted in which the developer is charged and the developer is transferred to the photosensitive drum by the charge. In this system, the developer is carried on the outer periphery of the developing roller, and the amount of the developer supplied by the rotating developing roller is regulated by a developing blade attached in a posture facing the outer peripheral surface, and this blade. The developer is triboelectrically charged.

  As such a developing blade, a rubber member having sufficient flexibility to form a gap through which the developer passes and characteristics necessary for frictionally charging the developer are bonded to a thin metal plate. Things are widely adopted.

  Conventionally, a developing blade for regulating the amount of developer is a transfer molding method in which a metal plate pre-applied with an adhesive primer (hereinafter referred to as a primer) is inserted into a predetermined position in a mold. Alternatively, a method is used in which a rubber material is injected into a mold cavity using an injection molding method and molded into a state in which a silicone rubber member or the like is attached to a metal plate in the mold.

  For example, Patent Document 1 discloses a method for manufacturing a developing blade free from burrs and sink marks, and a rib member protruding in the plate width direction is provided on a rubber member bonded to a metal plate, and a gate for injecting material is provided on the metal plate It is not a side but a rib part. As a result, a developing blade having no burrs, sink marks, or welds on the contact surface with the developing roll can be manufactured.

Patent Document 2 applies a primer for adhering a rubber member, leaving a blank area where nothing is provided on one side of the developing blade and a rubber adjacent area adjacent to the blank area. Here, the blank area is an area where nothing is adhered because it is used when a developing blade is set on the OA device or after a desired sealing material is pasted. It should be noted that the primer is allowed to be applied to the blank area for the convenience of manufacturing the developing blade. In Patent Document 2, a mold is set so that a cavity is positioned on a rubber arrangement area, and a rubber material is further guided from a point on the outer edge to the rubber arrangement area and injected into the cavity to mold a rubber member on a metal plate. Here, the primer is applied leaving a blank area and a part of the rubber adjacent area adjacent thereto. Therefore, even if the rubber material is guided from the point on the outer edge to the rubber placement area on the developing blade and injected into the cavity, the rubber member guided to the cavity does not remain in the product while being adhered to the blank area. Since the rubber remaining in the portion (injection path) can be removed after molding, the mold structure can be simplified.
JP 2004-163615 A JP 2005-274644 A

  As with other products, the above-described developing blade is required to be manufactured more efficiently from the viewpoint of improving work efficiency and reducing costs. However, in the method according to Patent Document 1, the runner portion of the mold is formed in the blank area. Therefore, it is necessary to remove a rubber material (hereinafter referred to as “residual rubber”) that remains in the runner portion and is cured after molding. The developing blade cannot be shipped as a product unless the remaining rubber removal operation is completed. Further, when the residual rubber comes into contact with a primer applied to adhere the rubber member to the metal plate, the removal operation becomes extremely difficult. Therefore, it is necessary to remove the primer application area and design the runner so that the remaining rubber does not come into contact with the primer application area. This also complicates the mold design and makes the mold manufacture. Cost increases.

  On the other hand, the manufacturing method proposed in Patent Document 2 avoids the blank area and the primer coating region and arranges the runner portion of the mold. Therefore, compared with the technique proposed in Patent Document 1, the manufacturing complexity is improved. However, even in the manufacturing method proposed in Patent Document 2, it is still necessary to remove the remaining rubber after molding. That is, there is still room for improvement in that the remaining rubber must be removed.

  Therefore, an object of the present invention is to propose a technique for efficiently producing a developing blade without requiring the operation of removing the remaining elastic material.

The above object is a mold used for manufacturing a developing blade in which a blank area is secured on both sides in the longitudinal direction on an elongated hard plate, and an elastic member that is brought into contact with the developer is adhered therebetween. , the overflow portion to recover the successive overflowing material as cavities and spaces in the elastic member is formed in a corresponding shape, Ri Oh provided in a predetermined area corresponding to between both blank area, the overflow portion A primer application region that includes an overflow receiving part and a throttle part that narrows a flow path cross-sectional area of the material filled in the cavity, and in which a primer is preliminarily applied to the hard plate to adhere the elastic member The throttle portion is configured to form part of the cavity and the overflow receiving portion and protrude from other portions. Is formed between the projecting portion, the overflow receiving portion, is formed as a space end, through the narrowed portion are continuous as a space only in the projecting portion, the developing blade mold, characterized in that Can be achieved.

Here, there is no limitation on the shape of the protrusion. When the shape of the elastic member bonded to the hard plate is a substantially rectangular shape (rectangular shape), the basic shape of the cavity is a rectangular shape accordingly.

  Further, a structure in which a thermosetting material is used as the material, an injection part for filling the material into the cavity is set, and a cold runner is provided in the injection part is more preferable.

  Further, the cavity is set so as to form a plurality of developing blades at the same time, and a sealing packing is provided around the cavity, and a vacuum drawing part is provided inside the packing. In addition, it may be configured to be connected to an external gas suction device through the vacuum drawing unit so that the periphery of the cavity can be vacuumed.

In the developing blade manufactured by the developing blade mold, an additional portion of an elastic member formed corresponding to the throttle portion and the overflow receiving portion of the die is provided in a predetermined region between the both blank areas. The additional portion of the elastic member exists continuously from the protruding portion of the elastic member formed corresponding to the protruding portion that forms a part of the cavity of the mold and protrudes from the other part. (Or left) The material is preferably made of liquid silicone to produce a developing blade. The developing blade may be manufactured by injecting a material into the mold, using the developing blade mold. Moreover, liquid silicone is preferable as the material to be injected.

  According to the present invention, the material overflowed to the overflow portion is recovered. This overflow part is continuously provided as a cavity and a space. The overflow portion is set to a predetermined area so that the material injected into the overflow portion can be left as it is between the two blank areas on the developing blade as a product. Therefore, the work itself for removing the remaining rubber can be stopped. That is, it is not necessary to perform the removing operation after molding the elastic member as in the conventional case. Accordingly, it is not necessary to design the runner part under severe conditions. According to the present invention, it is possible to simplify the structure by simplifying the structure of the mold. In particular, the present invention proposes a novel mold structure that is manufactured by leaving (remaining) the remaining rubber in a region (dead space) that is not affected by the developing blade as a product.

The overflow portion is continuously provided as a space with a protruding portion protruding from another part of the cavity . The overflow part is composed of an overflow receiving part for collecting the overflow and a throttle part formed between the overflow receiving part and the cavity . Providing the throttle portion can prevent material filling failure in the cavity.

  When the predetermined area is set inside the area corresponding to the primer application area (that is, in the primer application area), the overflow portion of the developed developing blade can be bonded and fixed with the primer. Therefore, it is possible to prevent inconveniences caused by leaving the left overflow part.

  Furthermore, if the mold is provided with a cold runner, the remaining rubber on the supply side can be eliminated. Further, a sealing packing is provided around the cavity, and the material can be reliably guided to the overflow portion in a structure in which a vacuum evacuation portion is provided inside the packing.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing a state in which a developing blade manufactured using the mold of this embodiment is attached to an OA apparatus. FIG. 2 is a front view of the developing blade taken out. The developing blade 1 includes a metal plate 2 as a thin plate having a long and thin shape, 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 two-component curable polyurethane, fluorine rubber, chloroprene rubber, and liquid silicone rubber can be preferably used, but it is said to be excellent in productivity. In view of this, it is particularly preferable to use liquid silicone rubber.
The metal plate 2 can be formed of, for example, stainless steel. Further, the rubber member 3 is bonded and fixed to a central portion in the longitudinal direction of the metal plate 2 by a primer. More specifically, the blank area BA described above is set on both sides of the developing blade 1, and the rubber member 3 is bonded between the blank areas BA.

  As shown in FIG. 1, the developing blade 1 is disposed in a posture in contact with the circumferential surface of the rotating developing roller 100 or in a posture having a slight gap with the circumferential surface, and the developer on the circumferential surface 100 a of the developing roller. It functions to regulate the layer thickness of 101.

  As shown in FIG. 2, the rubber member 3 is bonded to one side of the developing blade 1. In general, the generally planar shape of the rubber member 3 is roughly rectangular. In order to bond such a rubber member 3, a primer is applied on the metal plate 2a to set a primer application region CT. For example, as shown in FIG. 2, the primer application region CT is set to a rectangular shape that is the same as or slightly larger than the rubber member 3. The primer application region is not limited to this, and the primer may be applied to a part or all of the blank area. Further, the outer shape of the rubber member 3 is appropriately provided with convex portions protruding outward or concave portions recessed inward at the end portion or the peripheral portion as necessary. In the case of the rubber member 3 shown in FIG. 2, projecting portions 3TA-1 and 3TA-2 projecting upward are formed at both ends. In general, such a protrusion is formed in order to provide a material injection port (gate portion) or the like. Here, in the illustrated structure, the additional portion 3PR of the elastic member extends further continuously from the one protruding portion 3TA-2. The additional portion 3PR is a terminal portion (dead end portion). The additional portion 3PR is designed to exist in a predetermined area between the protruding portions 3TA-1 and 3TA-2. Such a characteristic structure is derived from a mold used when the developing blade 1 is manufactured. This will be clarified in the description of the mold described later.

  Further, a mold suitable for manufacturing the developing blade 1 will be described with reference to the drawings. FIG. 3 is a plan view schematically showing an example of the structure of the lower mold 10 which is one of the molds used when the developing blade 1 is manufactured. Here, the upper die (not shown) has a shape corresponding to the lower die 10, and when placed on the lower die 10, a shape corresponding to the developing blade 1 is formed inside.

  The lower mold 10 illustrated in FIG. 3 is designed to take a large number of developing blades 1 (four in the illustration of FIG. 3). That is, in FIG. 3, four cavities CA-1 to CA-4 are formed in the lower mold 10 so as to simultaneously manufacture four developing blades. The metal plate 2 is held at a predetermined position of the lower mold 10, and the cavities CA-1 to CA-4 are set inside thereof. Therefore, after setting the metal plate 2 to which the primer has been applied in advance, the upper part is closed with an upper mold (not shown), and a material is filled in each of the cavities CA-1 to CA-4 to be cured. The developing blade 1 can be manufactured by molding the rubber member 3.

  Further, a characteristic structure applied to the mold of the present invention will be described in detail with reference to FIGS. First, the rubber member 3 bonded to the surface 2a of the metal plate 2 and the material overflowing from the cavity for forming the rubber member 3 will be described. A thermosetting rubber material can be suitably used as a material for forming the rubber member 3. The material of the thermosetting rubber is filled (injected) into a cavity CA (space) formed in the shape of the rubber member 3 from an external injection device (not shown). Here, it is possible to manufacture a developing blade having a uniform rubber member 3 adhered thereto by reliably filling the cavity with a material. Therefore, a little more (excess) material is supplied to the cavity CA and overflowed (leaked out) from the downstream side, so that the gas (air) in the cavity is surely expelled and the cavity is filled with the material. Is preferred. In particular, in a mold having a large number of molds as illustrated in FIG. 3, in order to suppress a filling variation between cavities and reliably manufacture a plurality of developing blades, a method of overflowing the material as described above is used. It is desirable to adopt.

  Here, for example, as shown in FIG. 5, it is conceivable to provide an overflow overflow portion 110 for guiding the material MA overflowed from the cavity CA for molding the rubber member to the outside. However, when the structure shown in FIG. 5 is adopted, the rubber in the overflow portion 110 becomes the above-described residual rubber after molding, and thus a removal operation is required. FIG. 5 also shows a structure in which a runner portion 120 for injecting material MA into the cavity CA is also shown. After the molding, the rubber in the runner portion 120 also becomes residual rubber, so that a removal operation is necessary. become. Therefore, what is shown in FIG. 5 is a mold with low manufacturing efficiency because the removal work pointed out above is required. FIG. 5 shows a case where the overflow part 110 and the runner part 120 exist in the blank area BA, and it is necessary to remove the remaining rubber.

  Now, referring to FIG. 3 again, the structure of the lower mold 10 will be described. Since each cavity CA-1 to CA-4 has the same structure, the upper cavity CA-1 will be described. When this cavity CA-1 is viewed in more detail, a main cavity (original cavity) MC-1 is formed as a main space for forming the rubber member 3, and is attached to the main cavity MC-1. , A small subcavity SC-1 which is continuous as a space is added. This subcavity SC-1 is formed as a terminal space (dead space). In FIG. 3, reference numeral 14 denotes an injection port (gate) for filling the material into the cavity CA-1.

The sub-cavity SC-1 is provided for the purpose of collecting the material overflowing from the main cavity MC-1 side. It can be assumed that the main cavity MC-1 is filled with the material by allowing the material to enter the subcavity SC-1. In addition, it is desirable to provide a constricted portion 11 that further narrows the channel cross-sectional area of the material between the main cavity MC-1 and the subcavity SC-1. Providing such a throttle portion 11 increases the flow resistance to the subcavity SC-1. Therefore, when the material overflows into the subcavity SC-1, the material is pushed in with a sufficient filling pressure (injection pressure). Therefore, it is possible to prevent the material from being poorly filled (short shot) and to obtain a sharp product with firm corners (edges).
Here, the subcavity SC-1 may correspond to an overflow receiving portion constituting the present invention. Further, the subcavity SC-1 and the throttle portion 11 can correspond to an overflow portion constituting the present invention.

  FIGS. 6A and 6B are diagrams illustrating a plurality of specific examples of the dimensions of the diaphragm 11 and the mold as specific examples. If part C (depth of the throttle part) shown in the figure is smaller than 0.01 mm, it becomes extremely difficult to flow the material, and only gas is discharged. That is, the throttle part 11 can also function as a gas vent part (gas escape part). The depth of the narrowed portion 11 is usually 0.01 to 0.15 mm, more preferably 0.05 to 0.10 mm. The width of the narrowed portion 11 is preferably 0.1 mm or more, more preferably 0.1 to 1.5 mm.

  In a conventional mold, it was natural that the portion that was overflowed and cured (residual rubber) was removed after molding. On the other hand, the mold of the present embodiment is designed so that such a removal operation is not necessary. In FIG. 3, the predetermined area where the subcavity SC-1 is set is, for example, an area corresponding to a primer application area CT where a primer for connecting the rubber member 3 (elastic member) to the metal plate 2 is applied. Is also set inside. Since the primer application region CT is a region where a primer is applied to the surface of the metal plate 2 in order to bond the rubber member 3 to the surface of the metal plate 2, the primer application region CT is equal to or slightly larger than the region where the rubber member 3 is bonded. On the other hand, the primer application region CT is separated from the blank area BA with a predetermined boundary BL. Here, the subcavity SC-1 is set as a dead space in the primer application region CT. That is, the subcavity SC-1 is installed by utilizing the remaining space in the primer application region CT that is left by adhering the rubber member 3.

  As described above, the subcavity SC-1 is provided as an overflow receiving portion for the overflowed material, but the original purpose is to form a state in which the material flows out from the main cavity MC-1. Therefore, the volume of the subcavity SC-1 itself may be small. A characteristic of the mold realized by this embodiment is that it does not perform the operation of removing the rubber material after molding, and is left in the dead space of the developed developing blade. is there. That is, the remaining rubber in the subcavity SC-1 exists (is left) as the additional portion 3PR in the developing blade 1 shown in FIG. When viewed from the developing blade 1 when it is a product, the additional portion 3PR of the elastic member has a meaningless protruding structure, but the additional portion 3PR does not become an obstacle when installed in the OA apparatus. In this way, in the past, the unnecessary rubber part after molding, which was supposed to be removed when the developing blade was manufactured, should be left in an area (dead space) that does not get in the way even after the product. Therefore, the gist of the present invention is to eliminate the troublesome and complicated rubber removing operation. If the remaining primer application region CT is effectively used as described above, the additional portion 3PR can be fixed with the primer. Therefore, it can be prevented that leaving the unnecessary additional portion 3PR of the elastic member causes a problem later.

  By the way, the main cavity MC-1 of the lower mold 10 shown in FIG. 3 is provided with projecting portions 12 and 13 that project part of both ends. Thus, if one protrusion 12 is provided in the main cavity MC and the material is filled, and the overflowed material is allowed to flow out through the other protrusion 13, the outer shape of the rubber member 3 can be simplified. Further, since the projecting portion functions as a material entrance and exit, the influence of the material flow can be reduced and the rubber member 3 can be formed uniformly. Therefore, the developing blade 1 shown in FIG. 2 has protruding portions 3TA-1 and 3TA-2 protruding upward at both ends of the rubber member 3. Further, in the structure in which a plurality of protrusions are provided as illustrated in FIG. 3, the space between the protrusions becomes the above-described dead space, so the subcavity SC-1 is set here and the additional part 3PR is disposed. It will be possible.

In the above configuration, the subcavity (overflow receiving portion) SC-1 extends along the longitudinal direction of the cavity from the protruding portion 13 from which a part of the main cavity MC-1 is protruded via the throttle portion 11. ing. However, the length of the subcavity SC-1 is not limited to this, and can be set short as shown in FIG. 4A, for example. Further, the formation position of the protruding portion is not limited to the end portion in the longitudinal direction of the cavity MC-1 as in the above configuration, but as shown in FIG. It can also be set as the structure formed.
Further, at that time, there may be one overflow portion that is continuous as a space from the protruding portion, or a plurality of overflow portions may be provided as shown in FIG. However, if the protrusion is formed at a position away from the end in the longitudinal direction of the cavity as shown in FIG. 4B, the material may be prevented from reaching the end of the cavity, resulting in a short circuit. There is. For this reason, in order to obtain a good blade without a short circuit, a configuration in which the protruding portion is provided at the end portion in the longitudinal direction of the cavity or the vicinity thereof is preferable.

  In the above description, it has been described that the removal processing of the material overflowing from the main cavity MC-1 (removal operation of the remaining rubber) is unnecessary. However, in the conventional mold, as described with reference to FIG. 5, since the runner portion for material injection is formed even when the material is filled into the main cavity MC-1, the injection side Residual rubber may be generated. Therefore, it is not enough to propose a technique that eliminates the need for removing only the overflowed material.

  In view of this, as an even more preferable form, a mold having a structure that eliminates the need to remove the remaining rubber after molding is proposed on the side of filling (supplying) the material. The mold includes a cold runner that fills the thermosetting material while cooling. This structure will be described with reference to FIG. In the above description, only the lower mold 10 is illustrated, but in FIG. 7, it is illustrated that the lower mold 10 and the upper mold 15 constitute the mold 5. FIG. 7 shows a structure example in which a cavity CA is provided on the upper mold 15 side. The cavity CA may be provided in the lower mold 10.

  As shown in FIG. 7, the runner portion 23 is configured as a cold runner that includes an outlet 24 a and is at least partially cooled by a cooling jacket 26. That is, the cold runner 23 that forms a cylindrical space is in contact with the cylindrical cooling jacket 26 via a bush 25 that forms the cylindrical space, and the cooling jacket 26 passes a cooling medium such as cooling water. 27 is provided, and this cooling medium is guided to and passed through the cooling pipe 27 to cool the cold runner 23 provided in the cylinder of the cooling jacket 26, and the material MA such as silicone rubber passing therethrough is cooled. It is kept at a temperature at which curing is difficult to proceed so as not to be cured.

In addition, a heater 32 for curing the thermosetting material MA injected into the cavity CA is provided around the cavity CA of the lower mold 10, while the upper mold 15 is formed there. Even if the material MA stays in the runner portion 23, a cooling pipe 31 for cooling the entire upper mold 15 is provided so as not to harden the material MA. Since the mold shown in FIG. 7 is provided with a cold runner for injecting the material into the cavity CA without curing the material, it is not necessary to remove the remaining rubber after molding on the supply side.

  Finally, a structure that is preferably provided in the mold according to the above-described embodiment will be described again 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 inside the packing 17 (passing under the packing in FIG. 3). Is provided. 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. When 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 overflowing material can flow smoothly to the subcavity SC-1.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

  As is apparent from the above description, according to the present invention, it is possible to provide a mold that improves the manufacturing efficiency of the blade used in the OA apparatus.

It is a schematic diagram which shows the state which attached the developing blade manufactured using the metal mold | die of this embodiment to OA apparatus. It is the front view which took out and showed the developing blade. It is the top view which showed typically the structure of the lower mold | type which is one side of the metal mold | die used for manufacture of a developing blade. (A), (b) is the figure shown about the metal mold | die concerning other embodiment concerning this invention. It is the figure shown about the problematic mold. (A), (b) is the figure shown about the metal mold | die structure of the specific example. It is sectional drawing which showed the example of a metal mold | die structure provided with the cold runner.

Explanation of symbols

1 Development blade 2 Metal plate (hard plate)
3 Rubber member (elastic member)
3PR additional part 3TA-1 projecting part 3TA-2 projecting part 5 mold 10 lower mold 11 restricting part 13 projecting part 15 upper mold 100 developing roller BA blank area

Claims (7)

A mold used for manufacturing a developing blade, which has a blank area on both sides in the longitudinal direction on a long rigid plate, and is bonded with an elastic member to be in contact with the developer.
Overflow unit for recovering successive overflowing material as cavities and spaces are formed in a shape corresponding to the elastic member, Ri Oh provided in a predetermined area corresponding to between both blank area,
The overflow portion includes an overflow receiving portion and a throttle portion that restricts a flow path cross-sectional area of the material filled in the cavity, and a primer is preliminarily applied to the hard plate to bond the elastic member. Provided in the area corresponding to the primer application area
The throttle portion is formed between the overflow receiving portion and a protruding portion that constitutes a part of the cavity and protrudes from another portion,
The mold for a developing blade , wherein the overflow receiving part is formed as a terminal space, and is continuous as a space only to the protruding part through the throttle part . A thermosetting material is used as the material,
Said material is an injection unit set for filling into the cavity, the developing blade mold according to claim 1, wherein the injection unit is cold runner are deployed, it is characterized. The cavities are set to be multi-cavity so as to form a plurality of developing blades simultaneously,
A sealing packing is provided around the cavity, and a vacuum suction part is provided inside the packing, and is connected to an external gas suction device via the vacuum suction part to vacuum the periphery of the cavity. The mold for developing blade according to claim 2 , wherein the mold is capable of being pulled. A developing blade produced by the developing blade mold according to any one of claims 1 to 3 ,
In a predetermined region between the two blank areas, there is an additional portion of an elastic member formed corresponding to the throttle portion and the overflow receiving portion of the mold,
The additional portion of the elastic member is continuous with the protruding portion of the elastic member formed corresponding to the protruding portion that constitutes a part of the cavity of the mold and protrudes from the other part. Developing blade. The developing blade according to claim 4 , wherein the material is liquid silicone. A development blade manufacturing method using the development blade mold according to any one of claims 1 to 3 ,
A method for producing a developing blade, wherein a material is injected into the mold. The method for manufacturing a developing blade according to claim 6 , wherein the material is liquid silicone.

Images