JP2006038953A - Blade assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blade assembly in which distortion is hardly caused on a metal blade member, which easily realizes the improvement of durability and by which the metal blade member is easily made to abut on a developer carrier with uniform pressure. <P>SOLUTION: In the blade assembly 10 where the metal blade member 11 is fixed on a supporting member 12 and the metal blade member 11 is disposed so as to abut on the developer carrier 13, the supporting member 12 and the metal blade member 11 are stuck with an adhesive, and both the difference of a solubility factor between the adhesive and the metal blade member 11 and the difference of a solubility factor between the adhesive and the supporting member 12 are both ≤15, and also cutting elongation percentage after the adhesive is hardened or solidified is set to ≥350%, and tensile strength is set to ≥3MPa. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a blade assembly for mounting a blade member that is brought into contact with and slides on a developer carrier such as various rolls in an image forming apparatus using an electrophotographic method, and particularly supports a metal blade member. The present invention relates to an improvement of a blade assembly fixed to a member.

  2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, a toner carrier, which is a developer stored in a hopper or the like, is provided with a developer carrying member composed of various rolls such as a toner conveying roll, a magnet roll, a photosensitive drum, and a developing roll. Via, it is transferred to a developing object such as paper.

  In such an image forming apparatus, the toner moves while being carried on each roll surface. At that time, a layer thickness regulating blade for regulating the layer thickness of the toner on the roll surface, and a charging for charging the toner. A blade for cleaning, a cleaning blade for removing toner, foreign matter, and the like remaining on each roll surface after a predetermined conveyance section are installed so as to contact the roll surface with a predetermined pressure.

  These developing blades and cleaning blades have a long blade member formed of metal or resin, and the blade member is fixed to a support member as a blade assembly in an immobile state or a movable state. It is installed.

In such a blade assembly, the metal blade member is usually fixed to the support member by using a screw or the like (see, for example, FIG. 3 of Patent Document 1 below), and the resin blade member has several locations. And those fixed to the support member by screws or the like and those bonded to the support member using an adhesive are known (for example, see Patent Documents 1 to 3 below).
JP 2000-206784 A JP 2000-137380 A Japanese Patent Laid-Open No. 11-231648

  However, conventionally, in a blade assembly using a metal blade member, it is fixed to the support member by a mechanical fixing means such as a screw. However, the metal blade member is made of a material having a thin spring property. Since the member is made of a material having no spring property such as resin or metal and is formed of different materials, there is a difference in thermal expansion coefficient. For this reason, when the temperature is changed during operation, such as a temperature rise, the metal blade member is likely to be deformed such as a minute strain, and the durability is also easily lowered. In addition, when the metal blade member is brought into contact with the roll with a large pressure, there is a slight difference in the deformation state between the position near the screw for fixing the metal blade member and the position away from the screw. There is a problem that a difference in the contact pressure in the vertical direction is likely to occur.

  Accordingly, it is an object of the present invention to provide a blade assembly that is less likely to be distorted in a metal blade member, is easy to improve durability, and is easy to abut a metal blade member on a developer carrier with uniform pressure. To do.

  The blade assembly according to claim 1, wherein the blade assembly according to claim 1, wherein a metal blade member is fixed to a support member, and the metal blade member is disposed so as to come into contact with the developer carrier. The support member and the metal blade member are bonded by an adhesive, and the difference in SP value (solubility factor) between the adhesive and the support member is 15 or less, and the adhesive is cut after being cured or solidified. The elongation is 350% or more and the tensile strength is 3 MPa or more.

  The invention described in claim 2 is characterized in that, in addition to the configuration described in claim 1, the adhesive is applied with a constant width over substantially the entire length of the metal blade member.

  The invention according to claim 3 is characterized in that, in addition to the structure according to claim 1 or 2, the thickness of the adhesive after curing or after solidification is 60 μm or more and 150 μm or less.

  The invention described in claim 4 is characterized in that, in addition to the structure described in any one of claims 1 to 3, the adhesive is a silicone-based adhesive.

  According to a fifth aspect of the present invention, in addition to the configuration according to any one of the first to fourth aspects, the metal blade member has an elastic modulus of 110 N or more and 195 N or less, and a spring limit value of 250 N / mm or more. It consists of a steel plate which does not contain hexavalent chromium of 470 N / mm or less.

  According to a sixth aspect of the present invention, in addition to the configuration according to any one of the first to fifth aspects, the metal blade member removes the developer attached to the surface of the developer carrying member. It is characterized by that.

  According to the first aspect of the present invention, since the adhesive that bonds the support member and the metal blade member has a difference in SP value of 15 or less than that of the support member, the adhesive strength at the interface with the support member. Furthermore, since the elongation percentage after curing or solidification of the adhesive is 350% or more and the tensile strength is 3 MPa or more, the metal blade member and the support member Strain caused by the difference in thermal expansion coefficient between them can be absorbed by deformation of the adhesive layer. Therefore, the metal blade member can be easily brought into contact with the developer carrying member with uniform pressure, and the metal blade member can be prevented from being deformed to improve durability, and the metal blade member is peeled off from the support member. And the durability of the blade assembly can be secured.

  According to claim 2, since the adhesive is applied with a constant width over substantially the entire length of the metal blade member, the metal blade member can be fixed to the support body over the entire length, and the metal blade member When the toner is brought into contact with the developer carrier, the deformation state can be made constant over the entire length, and the metal blade member can be brought into contact with the developer carrier with a uniform pressure.

  According to invention of Claim 3, it is easy to ensure the adhesive strength of an adhesive bond layer in the thickness after hardening or solidification of an adhesive agent being 60 micrometers or more and 150 micrometers or less.

  According to invention of Claim 4, if an adhesive agent is a silicone type adhesive agent, the above elongation at the time of cutting and tensile strength can be obtained easily, and it can use especially suitably.

  According to the invention described in claim 5, the metal blade member is made of a steel plate having an elastic modulus of 110N or more and 195N or less and a spring limit value of 250N / mm or more and 470N / mm or less, and has an appropriate spring property. Therefore, the metal blade member is easily elastically deformed, and the entire side edge of the metal blade member is easily brought into contact with the developer carrier uniformly. And since it consists of a steel plate which does not contain hexavalent chromium, the bad influence with respect to an environment can be reduced also at the time of disposal.

  According to the sixth aspect of the present invention, the metal blade member is a cleaning blade assembly that removes the developer adhering to the surface of the developer carrying member, and therefore, compared to a blade member made of a material such as a resin. Since the top part that is brought into contact with the developer carrying member can be sharply formed, it is preferable that the developer can be removed more easily.

  Embodiments of the present invention will be described below.

  1 to 3 show a blade assembly of this embodiment.

  In the figure, reference numeral 10 denotes a blade assembly mounted at a predetermined position of an image forming apparatus (not shown), in which a long metal blade member 11 is fixed to a support member 12 with an adhesive. In this blade assembly 10, as shown in FIG. 3, the substantially entire length of one side edge 11a of the metal blade member 11 is in contact with the surface of an object 13 such as a cleaning roll / transfer belt as a developer carrier. In this state, the mounting hole 14 is used to mount the image forming apparatus at a predetermined position using a screw or the like.

  Such a blade assembly 10 rotates the object 13 such as a cleaning roll and a transfer belt with the metal blade 11 in contact with it, and slides the side edge 11a of the metal blade member 11 on the surface thereof. Used by.

  Here, the image forming apparatus to which the blade assembly 10 is attached is, for example, a facsimile, a printer, a copier, or the like in an electrophotographic system. The blade assembly 10 is for mounting on the image forming apparatus in a state where the metal blade member 11 is in contact with the surface of an object 13 such as a cleaning roll and a transfer belt disposed in the image forming apparatus. Here, the metal blade member 11 may be fixed to the image forming apparatus in an immovable state so as to be always in contact with the object 13 such as a cleaning roll / transfer belt, and may be moved when necessary to move to the cleaning roll / transfer. It may be fixed to the image forming apparatus so as to be movable so as to be in contact with an object 13 such as a belt.

  Further, the object 13 such as a cleaning roll / transfer belt can be replaced in the same manner as long as it carries a developer such as a toner transport roll, a magnet roll, and a photosensitive drum, and is not particularly limited. Absent.

  The metal blade member 11 of the blade assembly 10 may be a developing blade that regulates the film pressure of the toner or is frictionally charged. However, the object 13 such as a rotating cleaning roll or transfer belt may be used. It can be suitably used for a cleaning blade used for removing toner remaining on the surface of the toner after a predetermined conveying section.

  The metal blade member 11 adheres to the surface of the object 13 because it is easier to form sharply one side edge to be brought into contact with the object 13 such as a cleaning roll and a transfer belt than a blade member formed of a material such as resin. This is because it is easy to remove the toner.

  In general, such a metal blade member 11 is brought into contact with an object 13 such as a cleaning roll or a transfer belt at a predetermined pressure, for example, 1 N or more, at a side edge 11a. The contact should be as constant as possible over the entire length. Therefore, the metal blade member 11 is preferably made of a material having an appropriate spring property. In particular, an elastic modulus conforming to JIS G 7602 01 is 110 N or more and 195 N or less, and a spring limit value conforming to JIS H 3130 is made of a metal having a spring limit value of 250 N / mm or more and 470 N / mm or less. The metal blade member 11 having such an elastic coefficient range and a spring limit value range has an appropriate spring property, so that it is easy to be elastically deformed, and the side edge 11a of the metal blade member 11 is made full length. It is easy to uniformly contact the object 13 such as a transfer cleaning roll or a transfer belt.

  Examples of the metal constituting the metal blade member 11 of the present invention include stainless steel, phosphor bronze, spring white and the like. In addition, these metals are composed of metal composite materials that have been subjected to various surface treatments such as plating, resin coating, vapor deposition, and coating with fluororesin-treated tape for various purposes such as improving corrosion resistance, wear resistance, and slipperiness. Things can be used.

  When such a metal blade member 11 is made of a hexavalent chromium-free steel plate that does not contain hexavalent chromium or a surface treatment that does not use hexavalent chromium is used, This is suitable because it can reduce the adverse effect on the surface.

  The support member 12 of the blade assembly 10 is made of metal as long as the metal blade member 11 has a strength capable of abutting against an object 13 such as a cleaning roll / transfer belt with a predetermined pressure. Or it may consist of materials other than metals, such as resin.

  The metal constituting the support member 12 may be made of the same material as the metal blade member 11.

  The adhesive that bonds the metal blade member 11 and the support member 12 is an adhesive whose adhesive strength measured according to JIS K6854-1 can be at least 10 N / cm or more. As the adhesive of the present invention, the elongation percentage after curing or solidification is 350% or more, and at the same time, the tensile strength measured by JIS K6251 needs to be 3 MPa or more.

  In the case of such a range of cutting elongation and tensile strength, the distortion of the metal blade member 11 with respect to the support member 12, for example, the temperature of the blade assembly 10 rises during operation of the image forming apparatus. Distortion due to expansion and contraction of each member caused by the difference in thermal expansion coefficient between the blade member 11 and the support member 12, the metal blade member 11 is brought into contact with an object 13 such as a cleaning roll / transfer belt at a predetermined pressure and elastically deformed. This is because the distortion caused by this can be absorbed by the elastic deformation of the adhesive.

  Examples of the adhesive having the elongation at break and the tensile strength after curing or solidification include silicone adhesives such as reaction curing type and thermosetting type.

  Such an adhesive must be selected and used according to the material of the metal blade member 11 and the material of the support member 12. That is, in this invention, it is an adhesive with good adhesiveness to the metal blade member 11, and the difference between the SP value (solubility factor) of the adhesive and the SP value (solubility factor) of the support member 12 is 15 or less. Select and use one. This is because it is easy to obtain sufficient adhesive strength not only at the interface between the adhesive and the metal blade member 11 but also at the interface between the adhesive and the support member 12 as long as the SP value is within this range.

  In order to bond the metal blade member 11 and the support member 12 with such an adhesive, for example, by applying various coating methods such as screen printing, the adhesive is applied to one or both of these and cured. Alternatively, it may be solidified. At that time, as shown in FIG. 1, it is preferable that the adhesive is applied to the side edge 12a of the support member 12 or inside the side edge 12a, as shown in FIG. Thus, it is preferable to apply the adhesive so that the adhesive exists in the region X having a constant width over substantially the entire length of the metal blade member 11. Here, the fact that the adhesive is applied over substantially the entire length means that the adhesive is applied to a position corresponding to substantially the entire range of the metal blade member 11 in contact with the object 13 such as a cleaning roll or a transfer belt. Is Rukoto.

  In this way, the metal blade member 11 can be fixed to the support member 12 over substantially the entire length, and the side edge is brought into contact with the object 13 such as a cleaning roll / transfer belt and displaced by elastic deformation. Since the length from 11a to the position fixed by the adhesive can be made uniform, the amount of deformation when the metal blade member 11 is brought into contact with the object 13 such as a cleaning roll or a transfer belt is made constant. The member 11 can be brought into contact with the object 13 with a uniform pressure over the entire length.

  Moreover, it is more preferable that the thickness of the adhesive after curing or solidification is 60 μm or more and 150 μm or less. This is because the strength of the adhesive layer can be easily ensured. That is, when the adhesive layer is thick, for example, the strength of the adhesive layer is likely to decrease due to air bubbles mixed in the adhesive, etc., but such a thickness prevents them. It is easy to secure sufficient adhesive strength. As a result, peeling between the metal blade member 11 and the support member 12 can be prevented.

  Therefore, according to the blade assembly 10 in which the metal blade member 11 is fixed to the support member 12 using the adhesive as described above, the adhesive has an SP value difference of 15 or less than that of the support member 12. Therefore, the adhesive strength at the interface with the metal blade member 11 and the adhesive strength at the interface with the support member 12 can be sufficiently increased, and the cut elongation after curing or solidification of the adhesive is 350% or more. In addition, since the tensile strength is 3 MPa or more, the strain caused by the difference in thermal expansion coefficient between the metal blade member 11 and the support member 12 can be absorbed by the deformation of the adhesive layer. Therefore, the metal blade member 11 can be easily brought into contact with the object 13 such as a cleaning roll / transfer belt with uniform pressure, and the metal blade member 11 can be prevented from being deformed to improve the durability. It is possible to prevent the blade member 11 from being detached from the support member 12 and to ensure the durability of the blade assembly.

  The embodiment described above can be changed as appropriate within the scope of the present invention. For example, in the above description, the metal blade member 11 is fixed to the support member 12 only with an adhesive. In the case of a blade assembly fixed using a metal screw or the like, it is naturally possible to use an adhesive together with fixing using a metal screw or the like.

  Examples will be described below.

Example 1
A support member 12 surface-treated with a urethane-modified olefin resin, a metal blade member 11 made of SUS304H, having a thickness of 0.08 mm, an elastic modulus of 193 N, and a spring limit value of 409 N / mm, are combined with a silicone adhesive. The blade assembly 10 shown in FIG. 1 and FIG. 2 was produced.

  The difference between the SP value of the support member 12 and the SP value of the adhesive was 3. Moreover, the thickness of the adhesive in the bonded state was 80 μm.

  Further, the elongation percentage after curing of this adhesive was 660%, and the tensile strength was 0.7 MPa.

The obtained blade assembly 10 was mounted as a cleaning blade so that the metal blade member 11 was in contact with a pressure of 10 gf / mm ² , and an acceleration test was performed using 100,000 sheets in a 28 ° C. environment.

  As a result, the developer remaining on the surface of the object 13 was not confirmed even after 100,000 sheets were used.

Comparative Example 1
The acceleration test was performed in exactly the same manner as in Example 1 except that a polyester-based adhesive (SP value 10.0) was used as the adhesive and the aluminum support member 12 (SP value 117) was used untreated on the surface. It was.

  In Comparative Example 1, the difference between the SP value of the support member 12 and the SP value of the adhesive was 107.

  As a result, the remaining developer was confirmed on the surface of the object 13 after 100,000 sheets were used.

1 is a front view of a blade assembly according to an embodiment of the present invention. It is a side view of the blade assembly of the embodiment. It is sectional drawing which shows the state which made the blade member of the same embodiment contact | abut to a roll.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Blade assembly 11 Metal blade member 12 Support member 13 Target objects, such as a cleaning roll and a transfer belt 14 Mounting hole

Claims (6)

In the blade assembly in which the metal blade member is fixed to the support member, and the metal blade member is disposed so as to contact the developer carrier,
The support member and the metal blade member are bonded by an adhesive,
The difference in SP value between the adhesive and the support member is 15 or less,
A blade assembly having a cut elongation after hardening or solidification of the adhesive of 350% or more and a tensile strength of 3 MPa or more. The blade assembly according to claim 1, wherein the adhesive is applied with a constant width over substantially the entire length of the metal blade member. 3. The blade assembly according to claim 1, wherein a thickness of the adhesive after being cured or solidified is not less than 60 μm and not more than 150 μm. The blade assembly according to any one of claims 1 to 3, wherein the adhesive is a silicone-based adhesive. The metal blade member is made of a steel plate not containing hexavalent chromium having an elastic modulus of 110 N or more and 195 N or less and a spring limit value of 250 N / mm or more and 470 N / mm or less. The blade assembly according to claim 1. 6. The blade assembly according to claim 1, wherein the metal blade member removes the developer attached to the surface of the developer carrying member.

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