Patent Description:
There has been known an electro-photographic type image-forming apparatus such as a laser printer and an LED printer. A developing cartridge is used in the image-forming apparatus. The developing cartridge includes a developing roller for supplying toner. <CIT> discloses a conventional developing cartridge that includes a holder holding a storage medium.

For recycling a developing cartridge including a storage medium, information stored in the storage medium is rewritten, or the storage medium is exchanged with a new storage medium. However, according to the above-identified conventional developing cartridge, a cover holding the holder is fixed to a casing of the developing cartridge by screw-fixing. Hence the cover must be detached from the casing each time data rewriting or exchange of the storage medium is performed. Accordingly, workload for recycling is increased.

From post-published prior art document <CIT> it is known a cartridge that includes: a housing; a storage medium; and a holder. The storage medium has an electrical contact surface. The holder is movable relative to the housing. The holder includes: a first holder member; and a second holder member. The first holder member has a pawl portion and is configured to hold the electrical contact surface. The second holder member includes a corner portion. The pawl portion is engageable with the corner portion. The second holder member has a through-hole. An engagement part of the pawl portion engaging with the corner portion is accessible from outside the second holder member through the through-hole in a state where the pawl portion engages with the corner portion.

From prior art document <CIT> it is known a developing cartridge capable of being detachably arranged in a printer. The developing cartridge comprises a cartridge body and a chip assembly, wherein the chip assembly is arranged on a surface of the cartridge body matching the printer, and comprises a chip fixing frame, a chip and a chip assembly control mechanism.

From prior art document <CIT> it is known a toner cartridge that includes: a toner container for containing a toner, the toner container being removably mounted in an image forming apparatus; and a storage section for electronically storing specific information held by the toner container, the storage section being electrically connected to a to-be-connected portion of the image forming apparatus when the toner container is mounted in the image forming apparatus, the storage section comprising: a board assembly including a board on which a storage element for storing the specific information held by the toner container as electronic information is mounted; a housing member for holding the board assembly; and a covering member for detachably integrating the board assembly and the housing member, the storage section being attachable to and removable from the toner container.

In view of the foregoing, it is an object of the invention to provide a technique for reducing workload incurred for recycling of a cartridge including a holder.

According to the aspects (<NUM>)-(<NUM>) of the present invention, pressing the pawl through the through-hole can realize disengagement of the pawl from the corner part. With this configuration, the first holder member holding the electrical contact surface can be removed while the second holder member is left in the cartridge, thereby reducing the number of processes incurred for recycling the cartridge. Further, since the through-hole is open at the end face at the another side of the second holder member in the first direction, the pawl is accessible from the another side in the first direction of the holder.

According to the aspect (<NUM>) of the present invention, the first hook part and the second hook part are both accessible in the same direction, while the first hook part and the second hook part protrude in opposite directions from each other.

According to the aspect (<NUM>) of the present invention, the engagement of the pawl with the corner part can prevent detachment of the first holder member from the second holder member.

According to the aspect (<NUM>) of the present invention, the first holder member can be detached from the second holder member with the coil spring connected to the second holder member.

According to the aspect (<NUM>) of the present invention, the coil spring can be fixed to the large diameter portion, while the small diameter portion can prevent the coil spring from getting tilted.

According to the aspect (<NUM>) of the present invention, the pawl is accessible through the through-hole without removal of the holder cover.

According to the aspect (<NUM>) of the present invention, the first holder member can be detached without removal of the holder cover from the housing. This configuration can prevent occurrence of distortion of screw holes caused by fastening and unfastening of screws.

The particular features and advantages of the embodiment(s) as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which:.

Hereinafter, a developing cartridge <NUM> according to one embodiment of the present disclosure will be described with reference to accompanying drawings.

In the following description, a direction crossing an electrical contact surface <NUM> (<FIG>) will be referred to as a "first direction". Further, an extending direction of a rotation axis of a developing roller <NUM> (<FIG>) will be referred to as a "second direction". Further, a direction connecting between one end of a casing <NUM> of the developing cartridge <NUM> where the developing roller <NUM> is positioned and another end of the casing <NUM> opposite the one end of the casing <NUM> will be referred to as a "third direction". The first direction and the second direction cross each other, and preferably, perpendicular to each other. The second direction and the third direction cross each other, and preferably, perpendicular to each other. The third direction and the first direction cross each other, and preferably, perpendicular to each other.

<FIG> is a perspective view of the developing cartridge <NUM>. <FIG> is a partial exploded perspective view of the developing cartridge <NUM>. The developing cartridge <NUM> is used in an electro-photographic type image-forming apparatus, such as a laser printer and an LED printer.

The developing cartridge <NUM> is configured to be attached to a drum cartridge. Further, the drum cartridge to which the developing cartridge <NUM> is attached is configured to be attached to the image-forming apparatus. The developing cartridge <NUM> is configured to supply developing agent such as toner to a photosensitive drum of the drum cartridge. Incidentally, a single developing cartridge <NUM> may be attached to the single drum cartridge, or a plurality of developing cartridges <NUM> may be attached to the single drum cartridge.

As illustrated in <FIG> and <FIG>, the developing cartridge <NUM> includes the casing <NUM>, the developing roller <NUM>, a gear cover <NUM>, a memory assembly <NUM>, and a holder cover <NUM>.

The casing <NUM> is configured to accommodate therein developing agent. The casing <NUM> has a first outer surface <NUM> and a second outer surface <NUM> spaced apart from the first outer surface <NUM> in the second direction. The gear cover <NUM>, the memory assembly <NUM>, and the holder cover <NUM> are positioned at the first outer surface <NUM>. The casing <NUM> extends in the second direction between the first outer surface <NUM> and the second outer surface <NUM>. The casing <NUM> has an interior functioning as an accommodation chamber <NUM> for accommodating therein the developing agent.

The developing roller <NUM> is rotatable about a rotation axis extending in the second direction. The casing <NUM> has an opening portion <NUM>. The opening portion <NUM> provides communication between the accommodation chamber <NUM> and an outside of the casing <NUM>. The opening portion <NUM> is positioned at one end of the casing <NUM> in the third direction. The developing roller <NUM> is positioned at the opening portion <NUM>. That is, the developing roller <NUM> is positioned at the one end in the third direction of the casing <NUM>.

The developing roller <NUM> includes a developing roller body <NUM> and a developing roller shaft <NUM>. The developing roller body <NUM> is hollow cylindrical and extends in the second direction. The developing roller body <NUM> is made from elastic material such as rubber. The developing roller shaft <NUM> is a solid cylindrical and extends throughout a length of the developing roller body <NUM> in the second direction. The developing roller shaft <NUM> is made from metal or electrically conductive resin.

Incidentally, the developing roller shaft <NUM> may not extend throughout the length of the developing roller body <NUM> in the second direction. For example, the developing roller shaft <NUM> may extend in the second direction from each end in the second direction of the developing roller body <NUM>.

The developing roller body <NUM> is fixed to the developing roller shaft <NUM>, so that the developing roller shaft <NUM> is non-rotatable relative to the developing roller body <NUM>. Further, a developing roller gear (not illustrated) is fixed to one end of the developing roller shaft <NUM> in the second direction, so that the developing roller gear is non-rotatable relative to the one end of the developing roller shaft <NUM>. Accordingly, rotation of the developing roller gear causes co-rotation of the developing roller shaft <NUM> and the developing roller body <NUM>.

When driving force is transmitted to the developing cartridge <NUM>, the developing agent in the accommodation chamber <NUM> of the casing <NUM> is supplied therefrom to an outer peripheral surface of the developing roller <NUM> through a supply roller (not illustrated). At this time, the developing agent positioned between the supply roller and the developing roller <NUM> is subjected to tribo-charging. Further, a bias voltage is applied to the developing roller shaft <NUM> of the developing roller <NUM>. Hence, the developing agent is attracted to the outer peripheral surface of the developing roller body <NUM> by electrostatic force imparted between the developing roller shaft <NUM> and the developing agent.

The developing cartridge <NUM> further includes a layer thickness regulation blade (not illustrated). The layer thickness regulation blade is configured to regulate a thickness of the layer of the developing agent supplied to the outer peripheral surface of the developing roller body <NUM> into a uniform thickness. Then, the developing agent carried on the outer peripheral surface of the developing roller body <NUM> is supplied to the photosensitive drum of the drum cartridge. At this time, the developing agent is moved from the developing roller body <NUM> to the outer peripheral surface of the photosensitive drum in accordance with an electrostatic latent image formed on the outer peripheral surface of the photosensitive drum. Hence, the electrostatic latent image is developed into a visible image on the outer peripheral surface of the photosensitive drum.

The gear cover <NUM> is positioned at one end in the second direction of the casing <NUM>. The gear cover <NUM> is fixed to the first outer surface <NUM> of the casing <NUM>. The gear cover <NUM> constitutes a housing of the developing cartridge <NUM> in combination with the casing <NUM>. A plurality of gears including the above-described developing gear are positioned between the first outer surface <NUM> of the casing <NUM> and the gear cover <NUM>.

Next, the memory assembly <NUM> and the holder cover <NUM> will be described. <FIG> is a perspective view of the memory assembly <NUM>. <FIG> is an exploded perspective view of the memory assembly <NUM>. <FIG> and <FIG> are transverse cross-sectional views of the memory assembly <NUM>. <FIG> is a view of the memory assembly <NUM> and a portion in the vicinity thereof as viewed from another side in the first direction.

The memory assembly <NUM> is positioned at the one end in the second direction of the casing <NUM>. Specifically, the memory assembly <NUM> is positioned at an outer surface of the gear cover <NUM>. As illustrated in <FIG>, the memory assembly <NUM> includes a memory <NUM>, and a holder <NUM> holding the memory <NUM>. The memory <NUM> is positioned on an outer surface of the holder <NUM> at one side in the first direction.

The memory <NUM> is configured to store therein information about the developing cartridge <NUM>. Specifically, the memory <NUM> stores at least one of identification information and lifetime information on the developing cartridge <NUM>. The identification information may include at least one of a manufacturing serial number of the developing cartridge <NUM>; and an identification code as a proof of a genuine product. The lifetime information may include at least one of a volume of the developing agent; a service life of the developing roller <NUM>; information indicating a new product; a cumulative rotation number of the developing roller <NUM>; a cumulative number of printed sheets; and an error history. Further, the memory <NUM> may also store information about a model that matches with the developing cartridge <NUM>, in addition to the identification information and the lifetime information.

The memory <NUM> has four electrical contact surfaces <NUM>. The four electrical contact surfaces <NUM> are surfaces of electrically conductive metal exposed to the outside. The four electrical contact surfaces <NUM> are electrically connected to the memory <NUM>. The four electrical contact surfaces <NUM> are arrayed with each other in the second direction. Incidentally, the number of the electrical contact surfaces <NUM> may be not more than three, or not less than five.

As illustrated in <FIG>, the holder <NUM> includes a first end portion <NUM> and a second end portion <NUM>. The first end portion <NUM> corresponds to one end portion of the holder <NUM> in the first direction. The second end portion <NUM> corresponds to another end portion of the holder <NUM> in the first direction. The first end portion <NUM> and the second end portion <NUM> are spaced apart from each other in the first direction. Further, the first end portion <NUM> is movable in the first direction relative to the second end portion <NUM>.

Specifically, the holder <NUM> includes a first holder member <NUM>, a second holder member <NUM>, and a coil spring <NUM> positioned therebetween. The first holder member <NUM> is made from, for example, resin. The second holder member <NUM> is made from, for example, resin. The first holder member <NUM> is movable in the first direction relative to the second holder member <NUM>. The first holder member <NUM> includes the first end portion <NUM>. The memory <NUM> is held to an outer surface of the first end portion <NUM>. The second holder member <NUM> includes the second end portion <NUM>.

The coil spring <NUM> is resiliently deformable member extending in the first direction. The coil spring <NUM> is positioned between the first end portion <NUM> and the second end portion <NUM> in the first direction. The coil spring <NUM> has one end portion in the first direction connected to the first holder member <NUM>. The coil spring <NUM> has another end portion in the first direction connected to the second holder member <NUM>. Specifically, the second holder member <NUM> includes a columnar portion <NUM> as illustrated in <FIG> and <FIG>. The columnar portion <NUM> protrudes in the first direction toward the first end portion <NUM> from an inner surface of the second end portion <NUM>. The columnar portion <NUM> is inserted inside the coil spring <NUM>.

The columnar portion <NUM> includes a large diameter portion <NUM> and a small diameter portion <NUM>. The small diameter portion <NUM> is positioned closer to the first end portion <NUM> in the first direction than the large diameter portion <NUM> is to the first end portion <NUM>. Further, the small diameter portion <NUM> has a diameter smaller than a diameter of the large diameter portion <NUM>. The other end portion in the first direction of the columnar portion <NUM> is force-fitted with the large diameter portion <NUM>. Hence, the other end portion in the first direction of the columnar portion <NUM> is fixed to the second holder member <NUM>. Further, the small diameter portion <NUM> prevents the coil spring <NUM> from being inclined with respect to the first direction.

The coil spring <NUM> is configured to expand and compress in the first direction at least between a first state (illustrated in <FIG>) and a second state (illustrated in <FIG>). The coil spring <NUM> has a length in the first direction greater in the first state than in the second state. Hence, a distance between the first end portion <NUM> and the second end portion <NUM> in the first direction is greater in the first state than in the second state. Further, the length in the first direction of the coil spring <NUM> each in the first state and the second state is smaller than a natural length of the coil spring <NUM>.

As illustrated in <FIG> and <FIG>, the first holder member <NUM> includes a first pawl <NUM>, and a second pawl <NUM>. The first pawl <NUM> and the second pawl <NUM> are arrayed with each other in the second direction.

The first pawl <NUM> includes a first arm part <NUM> and a first hook part <NUM>. The first arm part <NUM> extends in the first direction toward the second end portion <NUM> from an inner surface of the first holder member <NUM>, the inner surface facing the second end portion <NUM>. The first hook part <NUM> protrudes from a tip end portion of the first arm part <NUM> toward the one side in the second direction (away from the gear cover <NUM>).

The second pawl <NUM> is positioned opposite to the first pawl <NUM> with respect to the columnar portion <NUM>. The second pawl <NUM> includes a second arm part <NUM> and a second hook part <NUM>. The second arm part <NUM> extends in the first direction toward the second end portion <NUM> from the inner surface of the first holder member <NUM>, the inner surface facing the second end portion <NUM>. The second hook part <NUM> protrudes from a tip end portion of the second arm part <NUM> toward the another side in the second direction (toward the gear cover <NUM>).

On the other hand, as illustrated in <FIG> and <FIG>, the second holder member <NUM> includes a first corner part <NUM> and a second corner part <NUM>. The first corner part <NUM> and the second corner part <NUM> are positioned inside the second holder member <NUM>. The first corner part <NUM> is provided by an intersection of a plane extending in the first direction with a plane extending in the second direction. The second corner part <NUM> is provided by an intersection of a plane extending in the first direction with a plane extending in the second direction. The first corner part <NUM> is positioned further toward the one side in the second direction than the second corner part <NUM>. The second corner part <NUM> is positioned opposite to the first corner part <NUM> with respect to the columnar portion <NUM>.

The first hook part <NUM> of the first pawl <NUM> is engageable with the first corner part <NUM> to provide a first engaging portion therebetween. The second hook part <NUM> of the second pawl <NUM> is engageable with the second corner part <NUM> to provide a second engaging portion therebetween.

The first hook part <NUM> engages the first corner part <NUM> in the first state of the coil spring <NUM>. That is, as illustrated in <FIG>, a surface of the first hook part <NUM> at the one side in the first direction (the surface facing the memory <NUM>) is in contact with the first corner part <NUM> in the first state of the coil spring <NUM>. Further, the second hook part <NUM> engages the second corner part <NUM> in the first state of the coil spring <NUM>. That is, as illustrated in <FIG>, a surface of the second hook part <NUM> at the one side in the first direction (the surface facing the memory <NUM>) is in contact with the second corner part <NUM> in the first state of the coil spring <NUM>. These engagements can prevent the length in the first direction of the coil spring <NUM> from being greater than that in the first state. Further, these engagements can prevent disengagement of the first holder member <NUM> from the second holder member <NUM>.

In contrast, in the second state of the coil spring <NUM> as illustrated in <FIG>, the first hook part <NUM> is separated away from the first corner part <NUM> toward the another side in the first direction (toward the second end portion <NUM>). Further, in the second state of the coil spring <NUM> as illustrated in <FIG>, the second hook part <NUM> is separated away from the second corner part <NUM> toward the another side in the first direction (toward the second end portion <NUM>).

The first holder member <NUM> further includes a sleeve part <NUM> and a guide rib <NUM>, as illustrated in <FIG>. The sleeve part <NUM> is hollow cylindrical and extends in the first direction to surround the coil spring <NUM>. As illustrated in <FIG>, the sleeve part <NUM> has a notch <NUM>. The notch <NUM> extends in the first direction to penetrate a portion of the sleeve part <NUM> in the second direction, the portion being at the one side in the second direction.

The guide rib <NUM> protrudes in the second direction from the sleeve part <NUM>, and extends in the first direction. The second holder member <NUM> has a key groove <NUM> extending in the first direction, as illustrated in <FIG>. The guide rib <NUM> is inserted in the key groove <NUM>, so that the first holder member <NUM> is guided in the first direction with respect to the second holder member <NUM>. As illustrated in <FIG> and <FIG>, the guide rib <NUM> has a tapered surface <NUM>. The tapered surface <NUM> is at a surface of the guide rib <NUM>, the surface facing the second pawl <NUM>. The tapered surface <NUM> is provided by diagonally cutting another end portion in the first direction of the guide rib <NUM>.

The holder cover <NUM> covers at least a portion of the holder <NUM>. The holder cover <NUM> is fixed to the outer surface of the gear cover <NUM>. Specifically, the holder cover <NUM> is screw-fixed to the gear cover <NUM>. Hence, the holder cover <NUM> is movable together with the casing <NUM> and the gear cover <NUM>. The second holder member <NUM> is held between the outer surface of the gear cover <NUM> and the holder cover <NUM>.

Incidentally, the holder cover <NUM> may be directly screw-fixed to the casing <NUM>, rather than to the gear cover <NUM>. Further, the screw-fixing of the holder cover <NUM> to the gear cover <NUM> can be treated as the "screw-fixing of the holder cover <NUM> to the housing".

As described later, in a configuration where the holder cover <NUM> is screw-fixed to the casing <NUM> or the gear cover <NUM>, only the first holder member <NUM> of the holder <NUM> can be detached from the holder cover <NUM> without unfastening screws from the holder cover <NUM>. Since unfastening of the screws is not required for the holder cover <NUM>, detachment of the first holder member <NUM> from the holder cover <NUM> can be realized without damaging positioning accuracy of the holder cover <NUM> relative to the housing. Further, fastening and unfastening of the screws with respect to the holder cover <NUM> and the casing <NUM> are required for a fewer number of times than otherwise, contributing to longer service life of the holder cover <NUM> and the casing <NUM>. Such long-term use of the holder cover <NUM> and the casing <NUM> is particularly beneficial for recycling of the developing cartridge <NUM>.

The second holder member <NUM> includes a first boss <NUM>, a second boss <NUM>, and a third boss <NUM>. The first boss <NUM> extends in the second direction toward the holder cover <NUM> from a surface of the second holder member <NUM>, the surface being opposite to a surface facing the gear cover <NUM>. On the other hand, as illustrated in <FIG>, the holder cover <NUM> has a cover hole <NUM>. The cover hole <NUM> penetrates one end portion of the holder cover <NUM> in the second direction. The first boss <NUM> is inserted in the cover hole <NUM>.

The second boss <NUM> and the third boss <NUM> extend in the second direction toward the gear cover <NUM> from the surface of the second holder member <NUM>, the surface facing the gear cover <NUM>. That is, the second boss <NUM> and the third boss <NUM> are positioned opposite to the first boss <NUM> with respect to the columnar portion <NUM>. The second boss <NUM> and the third boss <NUM> are arrayed with each other in the third direction.

On the other hand, the gear cover <NUM> has a first recess <NUM> and a second recess <NUM>. The first recess <NUM> and the second recess <NUM> are recessed from the outer surface of the gear cover <NUM> toward the another side in the second direction (toward the second outer surface <NUM>). The first recess <NUM> and the second recess <NUM> are arrayed with each other in the third direction. The second boss <NUM> is inserted in the first recess <NUM>. The third boss <NUM> is inserted in the second recess <NUM>.

Incidentally, the first boss <NUM>, the second boss <NUM>, and the third boss <NUM> may have a solid cylindrical shape or solid prismatic columnar shape.

The cover hole <NUM> has a dimension (inside dimension) in the third direction greater than a dimension (external size) of the first boss <NUM> in the third direction. Hence, the first boss <NUM> is movable in the third direction within the cover hole <NUM>. Further, the first recess <NUM> has a dimension (inside dimension) in the third direction greater than a dimension (external size) of the second boss <NUM> in the third direction. Hence, the second boss <NUM> is movable in the third direction within the first recess <NUM>. Further, the second recess <NUM> has a dimension (inside dimension) in the third direction greater than a dimension (external size) of the third boss <NUM> in the third direction. Hence, the third boss <NUM> is movable in the third direction within the second recess <NUM>.

Accordingly, the second holder member <NUM> is movable in the third direction, together with the first boss <NUM>, the second boss <NUM>, and the third boss <NUM>, relative to the casing <NUM>, the gear cover <NUM>, and the holder cover <NUM>. The first holder member <NUM> is caused to move in the third direction together with the second holder member <NUM> in accordance with the movement of the second holder member <NUM> in the third direction. Hence, the electrical contact surfaces <NUM> held by the first holder member <NUM> are also allowed to move in the third direction in accordance with the movement of the first holder member <NUM> in the third direction.

Likewise, the cover hole <NUM> has a dimension (inside dimension) in the first direction greater than a dimension (external size) of the first boss <NUM> in the first direction. Hence, the first boss <NUM> is movable in the first direction within the cover hole <NUM>. Further, the first recess <NUM> has a dimension (inside dimension) in the first direction greater than a dimension (external size) of the second boss <NUM> in the first direction. Hence, the second boss <NUM> is movable in the first direction within the first recess <NUM>. Further, the second recess <NUM> has a dimension (inside dimension) in the first direction greater than a dimension (external size) of the third boss <NUM> in the first direction. Hence, the third boss <NUM> is movable in the first direction within the second recess <NUM>.

Accordingly, the second holder member <NUM> is movable in the first direction along with the first boss <NUM>, the second boss <NUM>, and the third boss <NUM>, relative to the casing <NUM>, the gear cover <NUM>, and the holder cover <NUM>. The first holder member <NUM> is caused to move in the first direction together with the second holder member <NUM> in accordance with the movement of the second holder member <NUM> in the first direction, and hence, the electrical contact surfaces <NUM> held by the first holder member <NUM> are allowed to move in the first direction in accordance with the movement of the first holder member <NUM> in the first direction.

Incidentally, the holder cover <NUM> may have not less than two cover holes <NUM>. Further, the number of boss to be inserted in the cover hole <NUM> may be not less than two. Further, the gear cover <NUM> may have one recess or not less than three recesses. Further, the number of boss to be inserted in the recess of the gear cover <NUM> may be one or not less than three. Further, the gear cover <NUM> may have hole(s) instead of the recess(es).

Further, the second holder member <NUM> may also be movable in the second direction between the gear cover <NUM> and the holder cover <NUM>.

<FIG> is a cross-sectional view illustrating a state of the memory assembly <NUM> prior to attachment of the developing cartridge <NUM> to the drum cartridge. As illustrated in <FIG>, the drum cartridge includes a first guide plate <NUM> and a second guide plate <NUM>. The first guide plate <NUM> and the second guide plate <NUM> face each other and spaced away from each other in the first direction.

The first guide plate <NUM> has an electrical connector <NUM> made from metal and configured to contact the electrical contact surfaces <NUM> of the memory <NUM>. The electrical connector <NUM> protrudes toward the second guide plate <NUM> in the first direction from an outer surface of the first guide plate <NUM>. Further, the first guide plate <NUM> has a guide protrusion <NUM> protruding toward the second guide plate <NUM>. The guide protrusion <NUM> is positioned closer to an insertion opening of the drum cartridge (toward the another side in the third direction) than the electrical connector <NUM> is to the insertion opening in the third direction.

For attaching the developing cartridge <NUM> to the drum cartridge, the holder <NUM> is inserted into the insertion opening defined between the first guide plate <NUM> and the second guide plate <NUM>. At this time, the first holder member <NUM> is brought into contact with the first guide plate <NUM>, and the second holder member <NUM> is brought into contact with the second guide plate <NUM>. Since the holder <NUM> moves relative to the casing <NUM>, the holder <NUM> is nipped between the first guide plate <NUM> and the second guide plate <NUM>.

Then, the first holder member <NUM> is pushed by the guide protrusion <NUM> toward the second guide plate <NUM>, so that the length in the first direction of the coil spring <NUM> is reduced from the first state to the second state. Hence, the distance between the first end portion <NUM> and the second end portion <NUM> in the first direction is shortened. After the first holder member <NUM> moves past the guide protrusion <NUM>, the coil spring <NUM> again expands to increase its length in the first direction. Hence, the electrical contact surfaces <NUM> of the memory <NUM> are brought into contact with the electrical connector <NUM>. That is, the memory <NUM> and the electrical connector <NUM> are electrically connected to each other.

As described above, the holder <NUM> is movable in the first direction and the third direction relative to the casing <NUM>. Further, the holder <NUM> is capable of expanding and contracting in the first direction. With this structure, the electrical contact surfaces <NUM> can move along the guide protrusion <NUM>, regardless of a posture of the casing <NUM> during the insertion of the developing cartridge <NUM> into the drum cartridge. The electrical contact surfaces <NUM> are allowed to move in the first direction with respect to the electrical connector <NUM>, thereby restraining frictional wearing of the electrical contact surfaces <NUM>.

Further, the drum cartridge can perform a so-called "separating operation" for temporarily separating the developing roller <NUM> from the photosensitive drum after the developing cartridge <NUM> is attached to the drum cartridge. <FIG> illustrates a state of the developing cartridge <NUM> during a separating operation as viewed from the one side in the second direction. As indicated by a broken line arrow in <FIG>, at the time of the separating operation, the casing <NUM> of the developing cartridge <NUM> is caused to move toward the another side in the third direction relative to the drum cartridge due to the driving force from the image-forming apparatus.

In the separating operation, the position of the memory assembly <NUM> is fixed by the nipping between the electrical connector <NUM> and the second guide plate <NUM>. Therefore, the position of the memory assembly <NUM> relative to the drum cartridge can be maintained unchanged in spite of the movement of the casing <NUM> and the developing roller <NUM> in the third direction. In this way, the contact between the electrical contact surfaces <NUM> and the electrical connector <NUM> can be maintained even at the time of the separating operation, and frictional wearing of the electrical contact surfaces <NUM> and the electrical connector <NUM> can be restrained.

For recycling the developing cartridge <NUM>, information stored in the memory <NUM> is rewritten, or the memory <NUM> itself is exchanged with a new memory. To this effect, detachment of the holder cover <NUM> from the gear cover <NUM> may increase man-hours. Further, since the holder cover <NUM> is screw-fixed to the gear cover <NUM>, repeated unfastening and fastening of the screws may cause distortion in screw holes formed in the gear cover <NUM>.

The developing cartridge <NUM> according to the depicted embodiment has a structure for realizing detachment of the first holder member <NUM> with the second holder member <NUM> held between the gear cover <NUM> and the holder cover <NUM>. Hereinafter this structure will be described in detail.

As illustrated in <FIG>, the second holder member <NUM> has a first through-hole <NUM> and a second through-hole <NUM>. Further, the second holder member <NUM> has one end portion 60A at one side, and an end face 60B at the another side in the first direction. The first through-hole <NUM> and the second through-hole <NUM> are positioned at the end face 60B in the first direction of the second holder member <NUM>. That is, the first through-hole <NUM> and the second through-hole <NUM> are positioned in the second end portion <NUM> of the holder <NUM>. Accordingly, as illustrated in <FIG>, the first through-hole <NUM> and the second through-hole <NUM> are exposed to the outside through the holder cover <NUM>. Further, the first through-hole <NUM> and the second through-hole <NUM> are positioned apart from each other in the second direction.

The first through-hole <NUM> is open at the end face 60B in the first direction of the second holder member <NUM>, and extends in the first direction. The first through-hole <NUM> extends in the first direction toward the first hook part <NUM> throughout the second holder member <NUM> from the another side in the first direction. Therefore, the first engaging portion where the first hook part <NUM> of the first pawl <NUM> engages the first corner part <NUM> is accessible to an operator through the first through-hole <NUM> from the outside of the holder <NUM>.

The second through-hole <NUM> is positioned further toward the another side in the second direction than the first through-hole <NUM> is. The second through-hole <NUM> is open at the end face 60B in the first direction of the second holder member <NUM>, and extends in the first direction. The second through-hole <NUM> extends in the first direction toward the second hook part <NUM> throughout the second holder member <NUM> from the another side in the first direction. Therefore, the second engaging portion where the second hook part <NUM> of the second pawl <NUM> engages the second corner part <NUM> is accessible to the operator through the second through-hole <NUM> from the outside of the holder <NUM>.

For recycling the developing cartridge <NUM>, an operator inserts a tool (such as a screwdriver or a pair of tweezers) into the first through-hole <NUM> from the another side of the second holder member <NUM> in the first direction while the second holder member <NUM> remains held between the gear cover <NUM> and the holder cover <NUM>. Then, the operator uses a tip end of the tool to push the first hook part <NUM> in a direction away from the first corner part <NUM>. The operator thus realizes disengagement of the first hook part <NUM> from the first corner part <NUM>.

Further, the operator inserts the tool (such as a screwdriver or a pair of tweezers) into the second through-hole <NUM> from the another side of the second holder member <NUM> in the first direction while the second holder member <NUM> remains held between the gear cover <NUM> and the holder cover <NUM>. The operator then uses the tip end of the tool to push the second hook part <NUM> in a direction away from the second corner part <NUM>. The operator thus realize disengagement of the second hook part <NUM> from the second corner part <NUM>.

After the first pawl <NUM> and the second pawl <NUM> are disengaged respectively from the first corner part <NUM> and the second corner part <NUM>, the operator pulls out the first pawl <NUM> and the second pawl <NUM> from the second holder member <NUM> in the first direction toward the one side. In this way, the operator can remove the first holder member <NUM> from the second holder member <NUM> while the second holder member <NUM> remains held between the gear cover <NUM> and the holder cover <NUM>.

The operator then rewrites information stored in the memory <NUM> held by the removed first holder member <NUM>, or the operator replaces the memory <NUM> for a new memory. Thereafter, the operator inserts the first pawl <NUM> and the second pawl <NUM> of the first holder member <NUM> into the second holder member <NUM>. The operator then engages the first hook part <NUM> of the first pawl <NUM> and the second hook part <NUM> of the second pawl <NUM> with the first corner part <NUM> and the second corner part <NUM>, respectively.

As described above, in the developing cartridge <NUM> according to the present embodiment, the second holder member <NUM> has the first through-hole <NUM> through which the first pawl <NUM> of the first holder member <NUM> is accessible from the outside. The operator can thus push the first pawl <NUM> through the first through-hole <NUM> to realize disengagement of the first pawl <NUM> from the first corner part <NUM>. Further, the second holder member <NUM> has the second through-hole <NUM> through which the second pawl <NUM> of the first holder member <NUM> is accessible from the outside. The operator can press the second pawl <NUM> through the second through-hole <NUM> to realize disengagement of the second pawl <NUM> from the second corner part <NUM>. In this way, the first holder member <NUM> can be detached from the second holder member <NUM> with the second holder member <NUM> held between the gear cover <NUM> and the holder cover <NUM>.

As such, detachment of the holder cover <NUM> from the gear cover <NUM> is unnecessary for recycling the developing cartridge <NUM>. Therefore, the number of processes incurred for recycling can be reduced. Further, since repeated unfastening and fastening of the screws need not be performed, deformation of the screw holes does not occur in the gear cover <NUM>.

Further, the first through-hole <NUM> and the second through-hole <NUM> are both open at the end face 60B of the second holder member <NUM> in the first direction. Hence, the first engaging portion (where the first hook part <NUM> of the first pawl <NUM> engages the first corner part <NUM>) and the second engaging portion (where the second hook part <NUM> of the second pawl <NUM> engages the second corner part <NUM>) are both accessible to the operator from the outside of the second holder member <NUM> in the first direction from the same side (i.e., from the another side in the first direction).

Further, according to the present embodiment, the first hook part <NUM> of the first pawl <NUM> and the second hook part <NUM> of the second pawl <NUM> protrude in opposite directions from each other. However, the first hook part <NUM> and the second hook part <NUM> are both accessible to the operator in the same direction through the first through-hole <NUM> and the second through-hole <NUM>.

Further, as described above with reference to <FIG>, the sleeve part <NUM> has the notch <NUM> extending throughout a thickness of a portion of the sleeve part <NUM> in the second direction, the portion facing first pawl <NUM>. For disengaging the first pawl <NUM> from the first corner part <NUM>, the first pawl <NUM> is deformed toward the another side in the second direction (toward the gear cover <NUM>). At this time, a part of the first pawl <NUM> can be inserted in the notch <NUM>. In other words, the notch <NUM> of the sleeve part <NUM> can provide a space for allowing deformation of the first pawl <NUM> without increasing a size of the holder <NUM>.

Further, as described above with reference to <FIG> and <FIG>, the guide rib <NUM> has the tapered surface <NUM>. For disengaging the second pawl <NUM> from the second corner part <NUM>, the second pawl <NUM> is deformed toward the one side in the second direction (toward the holder cover <NUM>). At this time, a part of the second pawl <NUM> can be positioned in a space provided by the tapered surface <NUM>. In this way, the tapered surface <NUM> of the guide rib <NUM> can provide the space required for the deformation of the second pawl <NUM> without increasing the size of the holder <NUM>.

Next, a method for detaching the first holder member <NUM> from the second holder member <NUM> in the developing cartridge <NUM> will be described in further details.

<FIG> is a perspective view for description of detachment of the first holder member <NUM> from the second holder member <NUM> in the developing cartridge <NUM>. <FIG> are views for description of the detachment of the first holder member <NUM> from the second holder member <NUM> as viewed from the one side in the second direction. As illustrated in <FIG>, a first jig <NUM> is used for the detachment of the first holder member <NUM> from the second holder member <NUM>. The first jig <NUM> has a generally flat plate-like shape.

For detaching the first holder member <NUM> from the second holder member <NUM>, firstly, the operator sets the developing cartridge <NUM> on a surface of the first jig <NUM>, such that one end surface in the first direction of the casing <NUM> faces the surface of the first jig <NUM> as illustrated in <FIG> and <FIG>. Hence, the electrical contact surfaces <NUM> of the memory <NUM> face the surface of the first jig <NUM>.

The surface of the first jig <NUM> has a plurality of first protrusions <NUM>. The first protrusions <NUM> protrude toward the another side in the first direction from the surface of the first jig <NUM>. When placed on the surface of the first jig <NUM>, portions of the casing <NUM> of the developing cartridge <NUM> are in contact with the respective first protrusions <NUM>. Hence, the casing <NUM> is fixed in position relative to the first jig <NUM> in the directions crossing the first direction.

In this state, the operator inserts the tool (such as the screw driver and the tweezers) into the first through-hole <NUM> from the another side in the first direction. The operator then pushes the first hook part <NUM> in the direction away from the first corner part <NUM> with the tip end of the tool to disengage the first hook part <NUM> from the first corner part <NUM>. Further, the operator inserts the tool (such as the screw driver and the tweezers) into the second through-hole <NUM> from the another side in the first direction, and pushes the second hook part <NUM> in the direction away from the second corner part <NUM> with the tip end of the tool. The second hook part <NUM> is thus disengaged from the second corner part <NUM>.

At this time, the first hook part <NUM> is urged by the tool toward the another side in the second direction. The second hook part <NUM> is urged by the tool toward the one side in the second direction. Here, the tweezers may be used to pinch the first hook part <NUM> and the second hook part <NUM> such that the first hook part <NUM> and the second hook part <NUM> are urged to approach each other by the respective tip ends of the tweezers. Hence, the operator can simultaneously realize disengagement of the first hook part <NUM> and the second hook part <NUM> from the first corner part <NUM> and the second corner part <NUM>, respectively.

As a result of the disengagement of the first pawl <NUM> and the second pawl <NUM> from the first corner part <NUM> and the second corner part <NUM>, the first holder member <NUM> is urged to move toward the one side in the first direction because of the resilient urging force of the coil spring <NUM>, as illustrated in <FIG>. Here, since the first end portion <NUM> of the first holder member <NUM> faces the surface of the first jig <NUM> in the first direction, the first holder member <NUM> moving toward the first jig <NUM> comes into contact with the surface of the first jig <NUM>. Thus, popping out of the first holder member <NUM> can be prevented.

Thereafter, as illustrated in <FIG>, the operator moves the assembly of the casing <NUM>, the gear cover <NUM>, the holder cover <NUM>, and the second holder member <NUM> in a direction away from the surface of the first jig <NUM>, i.e., toward the another side in the first direction. Hence, the assembly of the casing <NUM>, the gear cover <NUM>, the holder cover <NUM>, and the second holder member <NUM> is separated away from the first holder member <NUM> toward the another side in the first direction. In this way, only the first holder member <NUM> holding the memory <NUM> can be detached from the developing cartridge <NUM> while the second holder member <NUM> is kept held between the gear cover <NUM> and the holder cover <NUM>.

Here, the other end portion in the first direction of the coil spring <NUM> is fixed to the large diameter portion <NUM> of the columnar portion <NUM> of the second holder member <NUM>. The other end portion in the first direction of the coil spring <NUM> remains fixed to the large diameter portion <NUM> when the first holder member <NUM> is removed from the second holder member <NUM>. Therefore, the coil spring <NUM> is also separated together with the second holder member <NUM> toward the another side in the first direction. Accordingly, detachment of the coil spring <NUM> can be prevented.

Next, a method for attaching the first holder member <NUM> to the second holder member <NUM> in the developing cartridge <NUM> will be described in more detail.

<FIG> is a perspective view illustrating a state of the developing cartridge <NUM> for description of attachment of the first holder member <NUM> to the second holder member <NUM>. <FIG> are views illustrating the state of the developing cartridge <NUM> as viewed from the one side in the second direction for description of the attachment of the first holder member <NUM> to the second holder member <NUM>. As illustrated in <FIG>, a second jig <NUM> is used for the attachment. The second jig <NUM> has a generally flat plate-like shape.

For attaching the first holder member <NUM> to the second holder member <NUM>, firstly, the operator sets the assembly of the casing <NUM>, gear cover <NUM>, holder cover <NUM>, and the second holder member <NUM> on the surface of the second jig <NUM> such that the surface of the casing <NUM> on the another side in the first direction faces the surface of the second jig <NUM>, as illustrated in <FIG> and <FIG>. Hence, the end face 60B of the second holder member <NUM> at the another side in the first direction faces the surface of the second jig <NUM>.

At this time, the end face 60B of the second holder member <NUM> extends perpendicular to the first direction. The end face 60B of the second holder member <NUM> is brought into contact with the surface of the second jig <NUM>, thereby setting the second holder member <NUM> on the surface of the second jig <NUM>. Accordingly, the second holder member <NUM> is set perpendicular to the surface of the second jig <NUM>. That is, the first direction becomes perpendicular to the surface of the second jig <NUM>.

The surface of the second jig <NUM> has a plurality of second protrusions <NUM>. The second protrusions <NUM> protrudes from the surface of the second jig <NUM> toward the one side in the first direction. Portions of the casing <NUM> positioned on the surface of the second jig <NUM> are in contact with the second protrusions <NUM>. The casing <NUM> is thus fixed in position relative to the second jig <NUM> in the direction crossing the first direction.

The coil spring <NUM> is attached to the second holder member <NUM>. Specifically, the other end portion in the first direction of the coil spring <NUM> is fixed to the large diameter portion <NUM> of the columnar portion <NUM>. Further, as illustrated in <FIG>, the one end portion in the first direction of the coil spring <NUM> protrudes out from the second holder member <NUM> and the holder cover <NUM> toward the one side in the first direction.

With this state, the operator moves the first holder member <NUM> toward the second holder member <NUM> from one side thereof in the first direction, as illustrated in <FIG>. Specifically, the operator moves the first holder member <NUM> toward the coil spring <NUM> protruding out of the second holder member <NUM>, as a target, in the first direction toward the another side. Then, the operator inserts the first pawl <NUM> and the second pawl <NUM> of the first holder member <NUM> into the second holder member <NUM>.

In response to the insertion into the second holder member <NUM>, the first arm part <NUM> of the first pawl <NUM> is deformed toward the another side in the second direction, and the second arm part <NUM> of the second pawl <NUM> is deformed toward the one side in the second direction. As the operator pushes the first holder member <NUM> further toward the another side in the first direction, the first hook part <NUM> and second hook part <NUM> move past the first corner part <NUM> and second corner part <NUM>, respectively. Accordingly, the deformed first arm part <NUM> restores its original shape to cause engagement of the first hook part <NUM> with the first corner part <NUM>, and the deformed second arm part <NUM> restores its original shape to cause engagement of the second hook part <NUM> with the second corner part <NUM>. Attachment of the first holder member <NUM> to the second holder member <NUM> is thus completed, as illustrated in <FIG>.

As described above, according to the depicted embodiment, the operator moves the first holder member <NUM> such that the first holder member <NUM> approaches the second holder member <NUM> in a state where the casing <NUM> and the second holder member <NUM> are kept immobile. Hence, the first holder member <NUM> holding the memory <NUM> can be readily attached to the second holder member <NUM>.

Further, the operator is required to do nothing other than bringing the first holder member <NUM> closer to the second holder member <NUM> to engage the first hook part <NUM> with the first corner part <NUM> by making use of the deformation of the first arm part <NUM>. That is, the operator can realize engagement of the first hook part <NUM> with the first corner part <NUM> without employment of a tool. Likewise, the operator is required to do nothing other than bringing the first holder member <NUM> closer to the second holder member <NUM> to engage the second hook part <NUM> with the second corner part <NUM> by making use of the deformation of the second arm part <NUM>. Therefore, the operator can realize engagement of the second hook part <NUM> with the second corner part <NUM> without employment of a tool.

In particular, the second holder member <NUM> is supported vertically with respect to the surface of the second jig <NUM>. This means that the direction in which the first holder member <NUM> is pushed against the second holder member <NUM> is perpendicular to the surface of the second jig <NUM>. This configuration can facilitate the operator's pushing of the first holder member <NUM> into the second holder member <NUM>.

According to the above-described embodiment, the first holder member <NUM> includes the first pawl <NUM> and the second pawl <NUM>. However, the first holder member may have one pawl or not less than three pawls. That is, the first holder member has only to have at least one pawl. Further, the second holder member has only to have at least one corner part engageable with the at least one pawl of the first holder member. Further, the second holder member has only to have at least one through-hole through which the engaging portion between the pawl and the corner part is accessible.

Further, according to the above-described embodiment, the memory <NUM> having the electrical contact surfaces <NUM> is fixed to the outer surface of the first end portion <NUM> of the holder <NUM>. However, only the electrical contact surface configured to contact the electrical connector of the drum cartridge may be fixed to the outer surface of the holder, and a portion of the memory other than the electrical contact surface may be arranged at a position of the developing cartridge different from the position of the electrical contact surface.

Further, the developing cartridge <NUM> according to the above-described embodiment is configured to be attached to the drum cartridge. However, the developing cartridge <NUM> may be of a type directly attachable to the image-forming apparatus without intervention of the drum cartridge. In the latter case, the image-forming apparatus may include the first guide plate <NUM> and the second guide plate <NUM>.

Further, the memory assembly just like the above-described memory assembly <NUM> may be provided in a cartridge other than the developing cartridge.

Further, shapes of detailed parts of the cartridge according to the invention may be different from those illustrated in the attached drawings. Further, parts and components appearing in the described embodiment and modifications thereof may be suitably selected and/or combined as long as no confliction is developed.

While the description has been made in detail with reference to the specific embodiment thereof, it would be apparent to those skilled in the art that many modifications and variations may be made thereto without departing from the scope of the invention.

Claim 1:
A cartridge (<NUM>) comprising:
a housing (<NUM>, <NUM>);
a storage medium (<NUM>) comprising an electrical contact surface (<NUM>); and
a holder (<NUM>) movable relative to the housing, the holder including:
a first holder member (<NUM>) holding the electrical contact surface (<NUM>) and including at least one pawl (<NUM>, <NUM>), the first holder member having one end surface in a first direction crossing the electrical contact surface (<NUM>), and the electrical contact surface (<NUM>) being positioned at the one end surface; and
a second holder member (<NUM>) movable relative to the first holder member (<NUM>), the second holder member (<NUM>) including at least one corner part (<NUM>, <NUM>) engageable with the at least one pawl to provide an engaging portion therebetween, the second holder member having one end portion (60A) at one side and an end face (60B) at another side in the first direction, and the second holder member (<NUM>) having a through-hole (<NUM>, <NUM>) that is open at the end face (60B) at the another side, the engaging portion being accessible from an outside of the holder through the through-hole (<NUM>, <NUM>),
characterised in that the at least one pawl includes a first pawl (<NUM>) and a second pawl (<NUM>),
wherein the at least one corner part includes: a first corner part (<NUM>) engageable with the first pawl to provide a first engaging portion therebetween; and a second corner part (<NUM>) engageable with the second pawl to provide a second engaging portion therebetween,
wherein the through-hole includes: a first through-hole (<NUM>) through which the first engaging portion is accessible from the outside of the holder (<NUM>); and a second through-hole (<NUM>) through which the second engaging portion is accessible from the outside of the holder (<NUM>), and
wherein the second through-hole (<NUM>) extends from the another side in the first direction, and
the first through-hole (<NUM>) extends from the another side in the first direction.