JP2011012707A - Powder leakage prevention structure, powder container, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power leakage prevention structure and a power container in which sealing is ensured.SOLUTION: The power leakage prevention structure includes a first member 13 provided with a connection surface 15 having an opening 14 which powder can pass through, an elastically compressible seal member 16 arranged on the connection surface 15 so as to surround the opening 14, and a second member 12 which can be mounted to the first member 13 so as to clamp the seal member 16. The second member 12 has an inclination part 19 whose tip end is located inside the seal member 16, which inclines toward outside so as to become far from the connection surface 15, and which presses the seal member 16 in such a way that an inside compression rate becomes higher. The drop of the seal member 16 into the opening 14 is inhibited by pressing the seal member 16 so as to include a component of a force that acts toward the outside circumferential side of the seal member 16.

Description

  The present invention relates to a powder leakage prevention structure, a powder container, and an image forming apparatus.

  When sealing the opening of a powder container such as a developing device, or when connecting a powder flow path to the opening of a powder container, ensure airtightness with a sealing member made of an elastic material such as foam rubber, It is common to prevent leakage of powder. As in the developing devices described in Patent Documents 1 to 3, in the conventional powder leakage prevention structure, a thick seal member is interposed between the connection surfaces facing each other.

  Since the seal member made of an elastic material is easily deformed, the seal member may be deformed when the seal member is disposed, and may be partially protruded inside the opening. Then, when the seal member is compressed between the connection surfaces, the portion protruding to the inside falls further so as to escape to the inside of the opening and deforms by undulation, and the seal between the connection surfaces is sufficient. It may disappear. Then, the problem that powder leaks out by vibration and impact occurs.

JP 2003-122114 A JP 2006-98645 A JP 2008-83441 A

  Provided is a powder leakage prevention structure that is surely sealed.

  In order to solve the above problems, a powder leakage preventing structure according to the present invention is provided on a first member having a connection surface having an opening through which powder can pass, and on the connection surface so as to surround the opening. An elastically compressible seal member; and a second member attachable to the first member so as to sandwich the seal member, wherein the second member suppresses the seal member from dropping into the opening. Therefore, the sealing member is configured to be pressed so as to include a component of force acting toward the outer peripheral side of the sealing member.

  According to this configuration, even if the seal member protrudes from the inside of the opening, the second member pushes the seal member outward, so that the seal member is not drawn into the inside of the opening. The undulation is prevented and the hermetic sealing of the connecting portion is ensured.

  Further, in the powder leakage preventing structure of the present invention, the second member may include an inclined portion whose tip is positioned inside the seal member and is inclined outwardly from the connection surface. .

  According to this configuration, when the sealing member is pressed by the second member, the inclined portion spreads the sealing member outward, preventing the sealing member from wavy and ensuring airtightness.

  In the powder leakage prevention structure of the present invention, the inclined portion may press the seal member so that the inner compression rate becomes high.

  According to this configuration, the drag due to the elastic compression of the seal member acts on the outer peripheral side, and the undulation of the seal member toward the opening can be prevented.

  Further, the powder leakage preventing structure of the present invention connects the innermost part of the inclined portion with which the seal member can come into contact with the inner edge of the opening in a state where the second member is attached to the first member. The straight line preferably has an angle of 90 ° or more with respect to the outer surface of the inclined portion.

  According to this configuration, since the pressing force of the inclined portion can be a pressure angle acting outward with respect to the seal member protruding from the opening, it is possible to reliably prevent the seal member from wavy.

  In the powder leakage prevention structure of the present invention, at least one of the first member and the second member defines a gap between the first member and the second member outside the seal member. It is preferable to provide a spacer part.

  According to this configuration, the compression rate of the sealing member can be made appropriate, and the sealing performance can be sufficiently exhibited. Further, by excessively pressing the inclined portion, it is possible to prevent the seal member from being pushed into the opening.

  In the powder leakage prevention structure of the present invention, it is preferable that the inclined portion is chamfered at a portion that abuts on an inner angle of the seal member.

  According to this configuration, excessive stress does not act on the corner of the seal member to cause tearing, and the seal member does not wave and the sealing performance is not deteriorated.

  A powder container according to the present invention, particularly an image forming apparatus, includes any one of the powder leakage prevention structures.

  According to this structure, powder does not leak from the connection part or sealing part of the container.

  According to the present invention, the powder leakage prevention structure is provided with the inclined portion that pushes the seal member to the outer peripheral side, so that the seal member is not drawn into the inside of the opening, preventing the seal member from undulating, Airtight connection is possible.

1 is a schematic view of an image forming apparatus including an embodiment of a powder leakage preventing structure according to the present invention. FIG. 2 is a cross-sectional view of the developing device and toner supply mechanism of FIG. 1. FIG. 3 is a perspective view of the developing device in FIG. 2. FIG. 3 is an exploded perspective view of the developing device in FIG. 2. FIG. 3 is a perspective view showing a bottom side of a chute of the developing device in FIG. 2. FIG. 3 is a schematic cross-sectional view of a joint structure of a developing device and a chute in FIG. 2. It is the elements on larger scale of FIG. FIG. 3 is a perspective view showing a developing device and a transport lid member of FIG. 2. It is a schematic sectional drawing of the image development apparatus of FIG. It is a schematic sectional drawing which shows the modification of this invention. It is a disassembled perspective view which shows the further modification of this invention.

  Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 shows an image forming apparatus 1 having a powder leakage prevention structure according to one embodiment of the present invention.

  The image forming apparatus 1 includes image forming units 2Y, 2M, 2C, and 2K that form images with toners that are powders of colors of yellow, magenta, cyan, and black. The image forming units 2Y, 2M, 2C, and 2K form electrostatic latent images on the surfaces of the photoreceptors 3Y, 3M, 3C, and 3K by the exposure device 4, and electrostatic latent images by the developing devices 5Y, 5M, 5C, and 5K. Toner is supplied to the image to form a toner image. New toner is supplied from the toner bottles 6Y, 6M, 6C, and 6K to the developing units 5Y, 5M, 5C, and 5K, respectively.

  The toner images formed by the image forming units 2Y, 2M, 2C, and 2K are primarily transferred to the intermediate transfer belt 7 and secondarily transferred to the recording paper supplied from the paper supply unit 9 by the secondary transfer roller 8. The The recording paper to which the toner image has been transferred is pressurized and heated by the fixing device 10, and the toner is melted to fix the image.

  FIG. 2 shows a connection structure between the developing device 5K and the toner bottle 6K. The toner is fed out by the supply screw 11 and is supplied into the developing device 5K from the opening 14 of the housing (first member) 13 of the developing device 5K through the chute (second member) 12. The chute 12 is attached to the housing 13 of the developing device 5K.

  As shown in FIG. 3, an elastically compressible seal member 16 made of, for example, urethane foam (such as Everlite STXE manufactured by Bridgestone) is provided on the connection surface 15 of the housing 13 facing the chute 12 so as to surround the opening 14. Has been placed. As a result, the seal member 16 is compressed between the housing 13 and the chute 12 and hermetically seals between the two.

  As shown in FIG. 4, the chute 12 has a lid 17 that seals the upper opening. Further, as shown in FIG. 5, the opening 18 facing the housing 13 of the chute 12 is a surface inclined so that the inner edge protrudes toward the housing 13 and away from the connection surface 15 of the housing 13 toward the outer side. It has the inclination part 19 which comprises. The corner between the inclined surfaces of the inclined portion 19 (the portion in contact with the inner angle of the seal member 16) is chamfered.

  FIG. 6 shows a simplified connection structure between the housing 13 and the chute 12, that is, a powder leakage prevention structure. The tip (inner edge) of the inclined portion 19 is formed to be sufficiently smaller than the opening 14 of the housing 13 so as to be located inside the seal member 16.

  Further, the housing 13 has a spacer portion 20 that defines a gap between the connection surface 15 and the chute 12 outside the seal member 16. As a result, the seal member 16 is compressed by about 33% (for example, compressed from 3 mm to 2 mm) at the outer peripheral portion, and the inner compression ratio is further increased. In the figure, the seal member 16 before compression is indicated by a two-dot chain line.

  When the chute 12 is attached to the housing 13, the inclined surface of the inclined portion 19 exerts a pressing force so as to include a force component acting toward the outer peripheral side of the seal member 16, thereby pushing the seal member 16 outward. spread. For this reason, as shown in the drawing, the inclined portion 19 does not pull the seal member 16 into the opening 15 even if the seal member 16 protrudes inside the opening 15. As a result, the seal member 16 can be prevented from dropping into the opening 14 due to unintentional deformation (waving), and the sealing performance can be prevented from deteriorating.

  Here, in order to make it easy for the inclined surface of the inclined portion 19 to exert the effect of pushing the seal member 16 outward, as shown in FIG. 7, the inner edge (point P) of the seal member 16 with which the inclined portion 19 abuts. It is preferable that the straight line (the direction in which the compressive stress acts) connecting the inner edge of the opening 15 (point E) has an angle of 90 ° or more with respect to the outer portion of the inclined surface of the inclined portion 19. Note that the shape of the inclined portion 19 needs to be determined in consideration of variations in the position of the P point due to the seal member 16 being displaced in position.

  Further, in this embodiment, since the corner of the inclined portion 19 that contacts the inner corner of the seal member 16 is chamfered, stress is not concentrated on the inner corner of the seal member 16, and the tearing and sealing performance of the seal member 16 are reduced. Such deformation (such as undulation) can be prevented. In this embodiment, R chamfering that forms a curved surface is performed, but C chamfering that forms a flat surface may be used.

  Further, as shown in FIG. 8, the developer 5K is transported to seal the opening 15 in order to prevent toner leakage when transported as a replacement part (especially after collection) and during replacement work. The lid member 21 can be attached. As shown in a simplified manner in FIG. 9, the transport lid member 21 has an inclined portion 22 that forms an inclined surface that spreads the seal member 16 outward, like the chute 12.

  Moreover, in this invention, as shown in FIG. 10, the inclination part 19 may comprise the inclined surface which consists of a curved surface.

  The present invention can also be applied to a connection structure related to an elliptical opening 14 having no corners as shown in FIG.

  Further, in the present invention, the connecting surface 15 on which the seal member 16 is disposed is formed on the chute 12 side, and the inclined portion 19 that presses the seal member 16 on the housing 13 side so as to include a component of force acting in the outer circumferential direction is formed. May be.

  Furthermore, the present invention is not limited to the developing device as in the above-described embodiment, but any powder container, and powder related to the connection or sealing of the powder flow path such as the connection between the toner bottle and the toner conveyance path. Widely applicable to leak prevention structures in general.

5K ... developer 12 ... chute (second member)
13 ... Housing (first member)
DESCRIPTION OF SYMBOLS 14 ... Opening 15 ... Connection surface 16 ... Seal member 19 ... Inclination part 20 ... Spacer part 21 ... Cover member 22 for conveyance 22 ... Inclination part

Claims (8)

A first member having a connection surface having an opening through which the powder can pass;
An elastically compressible seal member disposed on the connection surface so as to surround the opening;
A second member attachable to the first member so as to sandwich the seal member,
The second member presses the seal member so as to include a component of force acting toward the outer peripheral side of the seal member in order to suppress the seal member from dropping into the opening. Powder leakage prevention structure.   2. The powder leakage prevention according to claim 1, wherein the second member includes an inclined portion whose tip is positioned inside the seal member and is inclined outwardly from the connection surface. Construction.   3. The powder leakage prevention structure according to claim 1, wherein the inclined portion presses the seal member so that an inner compression rate becomes high. 4.   In a state where the second member is attached to the first member, a straight line connecting the innermost part of the inclined portion with which the seal member can come into contact with the inner edge of the opening is in relation to the outer surface of the inclined portion. The powder leakage prevention structure according to any one of claims 1 to 3, wherein the powder leakage prevention structure has an angle of 90 ° or more.   The at least one of the 1st member and the 2nd member is provided with the spacer part which defines the crevice between the 1st member and the 2nd member on the perimeter side of the seal member. The powder leakage prevention structure according to any one of 1 to 4.   The powder leakage prevention structure according to any one of claims 1 to 5, wherein the inclined portion is chamfered at a portion that abuts against an inner angle of the seal member.   A powder container comprising the powder leakage prevention structure according to any one of claims 1 to 6.   An image forming apparatus comprising the powder leakage preventing structure according to claim 1.

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