JPH0621052U - Cleaning blade - Google Patents

Abstract

(57) [Summary] [Structure] A support member 7 bent into a substantially L-shaped cross section, and a thick resin blade member 8 are attached to one end of the support member 7 along the longitudinal direction. Then, one surface B of the blade member 8 that is in sliding contact with the photosensitive drum is formed into a flat surface, and the other surface C is gradually thinned from approximately the center in the longitudinal direction of the blade member 8 toward both edges, and the thickness T of both edges is gradually reduced.
Is thinner than the other parts. [Effect] The stress applied to both ends of the blade member can be dispersed. As a result, the outer peripheral surface of the photosensitive drum is evenly slidably contacted without causing a situation such as turning over of both ends.
Moreover, that state can be maintained for a long period of time.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cleaning blade for removing toner remaining on the outer peripheral surface of a photosensitive drum of an electrophotographic copying machine or the like.

[0002]

[Prior art]

 An electrophotographic copying machine is equipped with a photosensitive drum with a photoconductor surface layer, the outer peripheral surface of this photosensitive drum is uniformly charged, and then the outer peripheral surface is exposed through a copied image of a copied object. A copy is performed by forming an electrostatic latent image on the outer peripheral surface, adhering toner to the electrostatic latent image to form a toner image, and transferring the toner image onto a copy paper or the like. After the copying, as shown in FIG. 6, since the toner 2 remains on the outer peripheral surface of the photosensitive drum 1, it is necessary to remove the residual charged toner 2. This removal is performed by the cleaning blade 3. I'm going. The cleaning blade 3 is configured by attaching a thick plate-shaped soft urethane resin blade member 5 to one end of a thin plate-shaped stainless steel support member 4 along the longitudinal direction. Then, the residual charged toner 2 is removed by the cleaning blade 3 by sliding the tip of the blade member 5 onto the outer peripheral surface of the rotating photosensitive drum 1. Therefore, the cleaning blade 3 is required to uniformly slidably contact the outer peripheral surface of the photosensitive drum 1 with the entire tip portion of the blade member 5.

[0003]

[Problems to be solved by the device]

 However, at both ends of the photosensitive drum 1, since the amount of the toner 2 is relatively smaller than that of the other portions, the lubricating action of the toner 2 is reduced. Therefore, at both end portions of the photosensitive drum 1, the frictional force of the blade member 5 becomes larger than that at the other portions, and a large stress is applied to both end portions of the blade member 5. This stress cannot be dispersed with the blade member 5 having a uniform thickness as shown in FIG. 4, so that both ends of the blade member 5 accompany the rotation of the photosensitive drum 1 and are indicated by a broken line A in FIG. The phenomenon of turning over occurs. This phenomenon is promoted when foreign matter or the like adheres to the outer peripheral surface of the photosensitive drum 1. Further, in the cleaning blade 3, as described above, a large stress is applied to both end portions of the blade member 5, so that partial material fatigue is caused early and, in some cases, damage occurs.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a cleaning blade capable of preventing curling of both end portions of a blade member and always performing stable cleaning.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the cleaning blade of the present invention comprises a supporting member and a cleaning blade member attached to one end of the supporting member along the longitudinal direction and one surface of which is in sliding contact with the outer peripheral surface of the photosensitive drum. In the blade, one surface of the blade member, which is in sliding contact with the photosensitive drum, is formed to be a flat surface, and the thickness of both ends of the blade member in the longitudinal direction is formed thinner than other parts. .

[0006]

[Action]

 That is, the cleaning blade according to the present invention is such that one side of the blade member that is in sliding contact with the photosensitive drum is formed into a flat surface, and both end portions of the outer peripheral surface of the photosensitive drum in which the toner on both end sides in the longitudinal direction of the blade member is less lubricated. The thickness of the part that is in sliding contact with is thinner than other parts. Therefore, this cleaning blade can reduce the frictional force between both ends of the photosensitive drum and both ends of the blade member compared to the conventional cleaning blade, and the stress applied to both ends of the blade member can be reduced. Can be dispersed. Therefore, it is possible to apply a uniform stress to the tip of the blade member, and the blade member is brought into even sliding contact with the outer peripheral surface of the photosensitive drum without causing a situation such as turning over of both ends of the blade member. Maintain for a long time.

Next, this invention will be described based on examples.

[0008]

【Example】

 FIG. 1 shows an embodiment of the cleaning blade of the present invention. That is, the cleaning blade 6 includes a support member 7 formed by bending a thin stainless steel plate into a substantially L-shaped cross section, and a thick-walled plate-shaped soft urethane attached to one end of the support member 7 in the longitudinal direction. It is composed of a resin blade member 8.

In the blade member 8, one surface B which is in sliding contact with the photosensitive drum is formed into a flat surface, and the other surface C is formed such that the thickness of the blade member 8 extends from the substantially center in the longitudinal direction to both end edges and is next thinned. Is formed on a curved surface. The upper end of the one side B is fixed to the support member 7.

The blade member 8 is formed such that the thickness T of both edges is within the range of 1/3 to 1/5 with respect to the thickness L of the substantially central portion thereof.

Using the 500 cleaning blades 6 configured as described above, assuming the start of rotation of the photosensitive drum 1, a turning-over test of the blade member 8 was performed as follows. First, as shown in FIG. 2, the cleaning blade 6 is attached to a fixing portion 10 provided upright on a base portion 9 that can slide back and forth as shown in the drawing. Next, as shown in FIG. 3, the tip of the blade member 8 of the attached cleaning blade 6 is brought into sliding contact with the outer peripheral surface of the photosensitive drum 1 rotating at a speed of 30 rpm, so that the blade member 8 of the blade member 8 is rotated. A turn-over test was conducted, and the number of blade members 8 that caused turn-up was counted. As a comparative example, as shown in FIG. 4, the supporting member 4 is the same as that in the above-described embodiment, and the thickness U of the blade member 5 is uniform throughout (this thickness is the same as that of the central portion of the embodiment product). 500 conventional cleaning blades 3 having the same thickness) were prepared and a flip-over test was conducted in the same manner as above. The number of blade members 5 in which flection was caused by this was counted. The above results are shown in Table 1 below.

[0012]

[Table 1]

From the results shown in Table 1 above, in the above-described example products, the entire blade member 8 can be slidably contacted with the outer peripheral surface of the photosensitive drum 1 in a state in which uniform stress is applied, and the swelling at both ends is Can be prevented. On the other hand, in the comparative example product, a large frictional force is applied to both ends of the blade member 5, and thus it is easy to turn the blade.

FIG. 5 shows another embodiment of the cleaning blade of the present invention. The cleaning blade 13 has stepped portions 15 formed as paragraphs at both ends along the longitudinal direction of the surface of the blade member 14 that does not come into sliding contact with the photosensitive drum. Except for this, the configuration is the same as that of the above-described embodiment, the same portions are denoted by the same reference numerals, and the effects are the same as those of the above-described embodiment.

[0015]

[Effect of device]

 As described above, in the cleaning blade of the present invention, one surface of the blade member that is in sliding contact with the photosensitive drum is formed to be a flat surface, and the thickness of both ends of the blade member in the longitudinal direction is formed thinner than other portions. There is. As a result, the frictional force of the blade member can be reduced at both ends of the photosensitive drum where the toner adhesion amount is small and the degree of wetting by the toner is small, and the blade member can be applied with uniform frictional stress. Can be brought into sliding contact with the outer peripheral surface of the photosensitive drum. Therefore, it is possible to prevent both ends of the blade member from being turned over, and it is possible to maintain the cleaning function of the blade member for a long period of time.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a cleaning blade of the present invention.

FIG. 2 is a structural diagram showing a method for testing a cleaning blade.

FIG. 3 is a structural diagram showing a method of testing a cleaning blade.

FIG. 4 is a perspective view showing a conventional cleaning blade.

FIG. 5 is a perspective view showing another embodiment of the cleaning blade of the present invention.

FIG. 6 is an explanatory view showing a usage state of a conventional cleaning blade.

[Explanation of symbols]

 6,13 Cleaning blade 7 Support member 8,14 Blade member B Plane

Claims (1)

[Scope of utility model registration request] 1. A cleaning blade comprising: a supporting member; and a blade member attached to one end of the supporting member in a longitudinal direction of the supporting member, one surface of which is in sliding contact with an outer peripheral surface of the photosensitive drum. A cleaning blade characterized in that one surface that is in sliding contact with is formed into a flat surface, and the thickness of both ends of the blade member in the longitudinal direction is formed thinner than other portions.