JP3233993B2 - Developer supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer supply device.

[0002]

2. Description of the Related Art In recent years, various proposals have been made for a developer replenishing device for supplying a developer to a developing means and an image forming apparatus provided with the developer replenishing device.

A conventional structure of such a developer replenishing device will be described with reference to FIGS.

Here, FIG. 6 is a perspective view showing an outline before the developer replenishing container is mounted on the developer replenishing device, and FIG. 7 is a longitudinal sectional view showing the developer replenishing device mounted with the developer replenishing container. is there. FIG. 8 is a sectional view taken along the line AA of FIG.
FIG. 3 is an explanatory diagram for explaining the developer supply operation. FIG.
(a), (b), (c) is an operation explanatory view of a lock mechanism for fixing a developer replenishing container to the developer replenishing device. FIG. 15 is a diagram illustrating a state in which the opening / closing lid is closed with the developer remaining in the developer replenishing container.

In FIG. 6, reference numeral 1 denotes a developer receiving container provided on the electrophotographic image forming apparatus side, and a developing device provided with a developing roller for supplying a developer to an electrostatic image carrier to form a developed image. The developer is conveyed from the developer receiving container 1 by a screw or the like.

Since the developer in the developer receiving container 1 is consumed as the image forming process proceeds,
It is necessary to replenish the developer appropriately, but the replenishment of the developer
Generally, this is performed by transferring the developer in the developer replenishing container 3 to the developer receiving container 1 of the image forming apparatus main body.

Further, an upper opening is formed in the container 1, and the upper opening is covered with a sliding type opening / closing lid (opening / closing means) 2 (FIG. 7). A slit 21 is formed on the upper surface of the opening / closing lid 2. On the other hand, a concave portion 14 into which the projecting portion 3b is inserted when the developer replenishing container 3 is mounted, and a guide 1a for guiding the insertion are formed in the upper portion of the developer receiving container 1. As shown in FIG. 6, the developer receiving container 1 has an engaging portion (fixing means) 1.
01 is provided, and the lock member 7 is engaged with the protrusion 33 of the developer replenishing container 3 to lock the developer replenishing container 3 at a predetermined position on the developer receiving container 1. . The detailed structure of the engagement portion 101 will be described later.

On the other hand, an appropriate amount of developer for replenishment is accommodated in the container main body 3a of the developer replenishing container 3, and its lower end opening is covered with a slide-type opening / closing lid (second opening / closing means) 4. Have been done. At the tip of the opening / closing lid 4, the tip 2 of the opening / closing lid 2 is attached.
2 is provided with a projection 41 which is hooked on the opening / closing lid 2.
The opening / closing lid 4 is also pushed in with the pushing in of. A thin hollow portion 42 having openings at both ends in the sliding direction (left and right ends in FIG. 7) is provided inside the opening / closing lid 4.

A sheet pull-out member 6 is fixed to the flange portion of the container body 3a, for example, by means such as pinching or click patching. 62 are formed. The lower end of the projection 62 is located in the slit 21 of the opening / closing lid 2. When the opening / closing lid 2 is pulled out, the lower end of the projection 62 is engaged with the end 23 of the slit 21 of the opening / closing lid 2 in the sliding direction. It has become. Further, the mounting strength of the sheet pull-out member 6 is not easily detached before the developer replenishing container 3 is mounted on the developer receiving container 1, and when the opening / closing lid 2 is pulled out, the end 23 in the sliding direction is used. The projection 62 is released by being pressed.

Further, a flexible sealing sheet 5 in the form of a film is adhered to the peripheral edge 31 at the lower end of the container body 3a by heat welding or the like. Prevents leaks. Note that the bonding strength of the sheet 5 is sufficient to enable peeling and prevent leakage of the developer.

Also, in the sliding direction of the opening / closing lid 2,
The total length of the sheet 5 is set to be at least twice the length of one side in the direction of the portion attached to the periphery of the lower end opening,
The remaining portion of the sheet 5 that is not stuck to the lower end opening of the container body 3a is folded back and disposed so as to pass through the hollow portion 42 of the opening / closing lid 4, as shown in FIG. .

Further, the end of the sheet 5 is stuck to the position 61 of the sheet pull-out member 6 with such strength that the sheet 5 does not easily come off, so that the sheet 5 does not come out of the container body 3a. The surplus part is the opening / closing lid 4 and the sheet drawer member 6
It is stored in a folded state. In addition,
The length of the surplus portion is set so that when the sheet pull-out member 6 is detached from the container body 3a, the operator can grasp and pull it.

The opening length K ₁ at the upper opening of the developer receiving container 1 is set to be larger than the opening length K ₂ at the lower opening of the developer replenishing container 3 (FIG. 7). the opening width W ₁ of the developer receiving container 1 is set to be larger than the opening width W ₂ of the developer replenishing container 3 (Fig. 8). That is, the opening area of the upper opening on the side of the developer receiving container 1 is configured to be as large as possible than the opening area of the lower end opening on the side of the developer replenishing container 3. Guide rail (sliding surface 32 and the like) is prevented from being contaminated by the splash of the developer. Further, the peripheral edge 31 of the lower end opening of the container body 3a to which the sheet 5 is adhered has a step (FIG. 8), and when the lid 4 slides along the sliding surface 32, Sliding resistance does not occur due to contact with the sheet 5.

Next, the procedure for supplying the developer will be described.

When supplying the developer to the developer receiving container 1, the developer replenishing container 3 is first mounted on a predetermined position of the developer receiving container 1 as shown in FIG. That is, the developer replenishing container 3 is placed on the developer receiving container 1 while the projecting portion 3b of the developer replenishing container 3 is inserted into the concave portion 14 of the developer receiving container 1. In this state, the protrusion 3b of the developer replenishing container 3 is restricted by the guide 1a and is prevented from moving upward.

On the other hand, the engaging portion 10 of the developer receiving container 1
14 is provided with a lock member 7 as shown in FIG. The lock member 7 is configured to rotate together with the lock member 72 about a rotation center axis 74, and an elastic member (a leaf spring or the like) 9 attached to the developer receiving container 1 is attached to the lock member 72. It is biased counterclockwise based on the contact. The lock member 7 has a claw 73 and is configured to engage with the protrusion 33 of the developer replenishing container 3 to lock the developer replenishing container 3.

The locking member 72 has a claw portion 71. The claw portion 71 is provided on the opening / closing lid 2 when the developer replenishing container 3 is not mounted on the developer receiving container 1. Engagement with the stop hole 24 prohibits sliding opening and closing of the opening / closing lid 2 (FIG. 14A).

When the developer replenishing container 3 is lowered in this state, the lock member 7 is moved to the projecting portion 33 of the developer replenishing container 3.
, And rotates clockwise against the urging force of the elastic member 9. When the developer replenishing container 3 is placed on the developer receiving container 1, the claw 73 of the lock member 7 engages with the protrusion 33 as shown in FIG. The container 3 is locked so that it cannot be removed. On the other hand, the claw portion 71 also rotates together with the lock member 7,
The engagement with the locking hole 24 is released, and the opening / closing lid 2 is slidable.

When the open / close lid 2 is pulled out in the direction of the arrow shown in FIG. 9, a slit provided in the upper part of the open / close lid 2 is provided shortly before the open / close lid 2 fully opens the upper opening of the developer receiving container 1. The terminal end 23 of 21 is engaged with the protrusion 62 of the sheet pull-out member 6, and the sheet pull-out member 6 starts to be detached from the container body 3a by the movement of the opening / closing lid 2 in the opening direction,
When the opening / closing lid 2 is fully opened, as shown in FIG. 10, the sheet pull-out member 6 is detached from the container main body 3a, and is pulled out to a position where an operator can grasp and pull it.

Next, when the operator holds the sheet pull-out member 6 and pulls the sheet 5 in the direction of the arrow in FIG. 10, the portion of the sheet 5 attached to the lower end opening of the container body 3a is folded back. The sheet 5 is sequentially peeled off from the side, and as shown in FIG. 11, the folded position of the sheet 5 moves in the pull-out direction, and the folded portion of the sheet 5 pushes the open / close lid 4 and moves in the opening direction. Then, the lower end opening of the developer replenishing container 3 is gradually opened, and the developer contained in the container main body 3a is dropped and supplied to the developer receiving container 1.

Then, as shown in FIG. 12, the lower end opening of the developer replenishing container 3 is fully opened and all the developer has dropped into the developer receiving container 1, ie, the sheet 5 is completely pulled out. Even in the opened state, the surface 5 a of the sheet 5 to which the developer is attached is stored in the hollow portion 42 of the opening / closing lid 4, so that the worker can touch the developer attached to the sheet 5. Therefore, the hands, clothes and surroundings of the worker are not contaminated by the developer. Therefore, a cleaning pad for scraping off the developer adhering to the sheet 5 becomes unnecessary, and the size and cost of the developer supply device can be reduced. Opening / closing lid 2
When the sheet 5 starts to be peeled from the container body 3a, it is in the fully opened state in advance, so that the developer falling from the developer replenishing container 3 does not contaminate the top surface of the front end of the opening / closing lid 2.

After the developer is replenished as described above, when the lid 2 is pushed and closed in the direction of the arrow in FIG. 12, the tip 22 of the lid 2 engages with the projection 41 of the lid 4, and 4 is pushed and closed, and the opening / closing lid 4 closes while pulling in the sheet 5 and the sheet pull-out member 6 drawn out of the container body 3a. At this time, even if the developer in the developer replenishing container 3 is biased and the developer is in the mountain in the developer replenishing container 3, the developer is leveled and the opening / closing lids 2 and 4 are opened. Closed. In such a case, since the tip of the opening / closing lid 2 is engaged with the projection 41 of the opening / closing lid 4, and the gap between the opening / closing lid 2 and the opening / closing lid 4 is closed by the projection 41, the developer enters the gap. Never. When the upper opening of the developer receiving container 1 is closed by the opening / closing lid 2 and the lower opening of the developer replenishing container 3 is completely closed by the opening / closing lid 4, the sheet 5 and the sheet pull-out member 6 are moved to the state shown in FIG. As shown in (2), the sheet drawer member 6 is stored in a state slightly protruding from the container body 3a.

In this state, as shown in FIG. 14 (c), when the cover 2 is further pushed in the direction of the arrow, the cam surface 25 of the cover 2 pushes the claw 71 of the lock member 7, and the lock member 7 is elastic. Rotating clockwise (in the direction of the arrow in the figure) against the member 9, the engagement between the claw 73 and the protrusion 33 of the developer replenishing container 3 is released. Therefore, the developer replenishing container 3 can be removed from the developer receiving container 1 by pulling out the protrusion 3b from the concave portion 14.

Next, when the operator stops the pushing operation of the opening / closing lid 2, the pawl portion 71 of the locking member 7, which is elastically urged in the counterclockwise direction by the elastic member 9, engages the cam surface 25. , The opening / closing lid 2 starts sliding again in the lid opening direction. Immediately thereafter, the claw portion 71 is fitted into the locking hole 24 of the opening / closing lid 2 by the urging force of the elastic member 9. Is stopped and locked in the release prohibition state.

[0025]

According to the prior art, however, the developer replenishing apparatus which transfers the developer in such a closed system cannot directly check the remaining amount of the developer. Therefore, the developer receiving container 1
In some cases, the developer is unnecessarily replenished even though a sufficient amount of the developer remains inside.

In such a case, for example, as shown in FIG. 15, the peaks of the developer are separated by the projections 41 of the opening / closing lid 4, that is, while the excess amount of the developer is pushed back to the developer replenishing container 3, And the cover 4 is closed.

However, when the opening / closing lid 2 is closed, the developer is compacted because it is easy to aggregate in the form of ultrafine particles.
5 becomes jammed, and comes off before the opening / closing lid 4 of the developer replenishing container 3 is closed, or
A situation occurs in which the developer replenishing container 3 does not come off.

In order to avoid this, as shown in FIG. 16, a buffer (buffer space) 200 for accommodating the developer overflowing from the developer receiving container 1 is provided.
As disclosed in Japanese Utility Model Laid-Open No. 2-132260, a device provided with a developer receiver for accommodating overflowing developer has been proposed.

However, in the case of the buffer 200 described above, it is necessary to return the developer contained in the buffer 200 to the developer receiving container 1 for the next replenishment of the developer so that there is no developer. Lower opening (second opening)
202 had been formed. Therefore, when the developer is supplied, the developer receiving container 1 passes through the lower opening 202 of the buffer 200, the buffer 200, the upper opening (the first opening) of the buffer 200, and the gap between the protrusion 3b and the guide 1a. As shown in FIG. 17B, there is a problem that the developer flows backward and leaks to the outside as shown in FIG. Since the developer has a high fluidity, a large amount of the developer leaks out, so that there has been a serious problem that the equipment around the developer replenishing container 3 and the clothes of the worker are widely stained. In some cases, the developer enters the inside of the image forming apparatus and deteriorates the quality of a formed image.

Further, when the developer receiver is detachably provided as disclosed in Japanese Utility Model Laid-Open No. 2-132260, there is a possibility that the developer may be scattered at the time of detachment.

Therefore, an object of the present invention is to provide a developer replenishing device which solves these problems.

[0032]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a developer receiving container having an upper opening and receiving replenishment of developer from a developer replenishing container; And a slide type opening / closing means for covering the portion, wherein the developer replenishing device receives supply of the developer from the developer replenishing container in a state where the opening / closing means is opened, and closes the opening / closing means after the replenishment is completed. A buffer space for temporarily storing surplus developer that becomes an obstacle when closing the opening / closing means is provided near the tip of the opening / closing means in the closing direction, and the buffer space is pressed by the opening / closing means. A first opening for storing the developer in the buffer space, a second opening for discharging the surplus developer into the developer receiving container, the buffer space and the developer receiving container. A third switching means for disconnecting the communication between with a, characterized in that.

In this case, a lower end opening facing the upper opening of the developer receiving container is formed in the developer replenishing container, and a second sliding opening / closing means is provided to cover the lower end opening. Attached to the refill container, and
Fixing means for fixing the developer replenishing container on the developer receiving container may be provided.

Further, there is provided an urging means for urging the third opening / closing means in a closing direction with a predetermined urging force, wherein the third opening / closing means has a predetermined amount or more of the developer entering the buffer space. In this case, the developer may be opened by its own weight to discharge the developer into the developer receiving container, and may be closed after the developer is discharged into the developer receiving container.

Further, the third opening / closing means closes the second opening of the buffer space in conjunction with the operation of placing the developer replenishing container on the developer receiving container. Yes, you may.

[0036]

Embodiments of the present invention will be described below with reference to the drawings.

First, an embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 1A shows a state of the buffer 200 when the developer replenishing container 3 is not mounted.
(b) shows a state when the developer replenishing container 3 is mounted, respectively. FIGS. 2 to 4 show the state when the opening / closing lid 2 is closed in a state where the developer remains in the developer replenishing container 3 as in FIG. 15, and FIG. 5 shows the opening / closing mechanism of the lid 500. , Respectively.

In this embodiment, the opening / closing lid (opening / closing means)
A buffer (buffer space) 200 for temporarily storing the developer is provided in the vicinity of the front end of the buffer 200 in the closing direction, and an upper opening (first opening) 201 of the buffer 200 is provided.
Has the same height as the upper opening of the developer receiving container 1. A lid 300 is provided at a height at which the opening / closing lid 2 above the buffer 200 slides.
0 is urged by the elastic member 400 in a direction to close the upper opening 201.

When the developer replenishing container 3 is mounted (FIG. 1B), the projecting portion 3b of the developer replenishing container 3 is
It is inserted between the guide 1a of the developer receiving container 1 and the lid 300, and the upward movement is regulated by the guide 1a. At this time, the protrusion 3b is
It is in contact with the lid 300 with such a strength as not to disturb the movement of the zero.

On the other hand, a lower end opening (second opening) 202 is provided at the lower end of the buffer 200, and the lower end opening 202 is provided with a lid rotatably supported about a rotation center axis 501. (Third opening / closing means) 500 is provided. A torsion coil spring (biasing means) 502 for biasing the lid 500 in the closing direction is wound around the rotation center shaft 501.

FIG. 5 is a schematic view showing a mounted state of a torsion coil spring 502 as an opening / closing mechanism of the lid 500.
FIG. 5 (a) is a view of FIG.
(b) is a diagram viewed from the cross-sectional direction. 503 in the figure
Reference symbols a and b denote coil spring detent shafts, and reference numerals 504a and b denote spring stoppers. By applying the tip of the torsion coil springs 502a and 502b to the coil spring rotation preventing shafts 503a and 503b, a predetermined urging pressure is applied in the direction of the arrow (FIG. 5B) to keep the lid 500 closed.

Next, the operation when the opening / closing lid 2 is closed will be described with reference to FIGS.

When the cover 2 is closed with the developer remaining in the developer replenishing container 3, the projection 41 of the cover 4 engages with the tip 22 of the cover 2 as shown in FIG. By 41, the developer is pushed apart. At this time, the upper opening 201 of the buffer 200 is closed by the lid 300 urged in the closing direction by the elastic member 400, and the lower opening 202 of the buffer 200 is closed by the lid 50.
Closed by 0. That is, the buffer 200
Is a closed space for the developer replenishing container 3 and the developer receiving container 1.

As shown in FIG. 3, when the opening at the lower end of the developer replenishing container 3 is closed by the opening / closing lid 4, that is, the developer (excess developer) which has nowhere to go in the portion T is projected by the projection 41. By the time the developer is pressed and the obstruction of the lid 2 occurs, a part 2
6 starts to push open the lid 300 against the biasing force of the elastic member 400.

Therefore, as shown in FIG. 4, the developer pressed by the opening / closing lid 2 (projection 41) is applied to the upper opening 20 as shown in FIG.
1 and into the buffer 200, the opening / closing lid 2 is closed together with the opening / closing lid 4 without being subjected to the resistance due to the developer having nowhere to go.

On the other hand, the developer that has entered the buffer 200 falls onto the lid 500 of the buffer 200, and accordingly, a pressure Q corresponding to the weight of the developer is applied to the lid 500. Acts to open. At this time, the lid 500 has an urging pressure P of the spring 502 in the closing direction.
The pressure is set so as to maintain the closed state. )
Further, the developer normally replenished in the developer receiving container 1 exerts a pressure T (pressure by the developer in the developer receiving container 1) from below the lid 500.

Therefore, the pressure Q acting to open the lid 500 and the pressure acting to close the lid 500 (P
+ T), the opening and closing operation of the lid 500 is performed.

That is, when a sufficient amount of the developer exists in the developer receiving container 1 even when the developer is in the buffer 200, the pressure T is large (T + P> Q), so that the lid 500 is in the closed state. Remains. However, when the amount of the developer in the developer receiving container 1 decreases and the amount of the developer pressing the lid 500 from below decreases, and the pressure T decreases, the pressure Q acting to open the lid 500 acts to close. It becomes larger than the pressure (P + T) (T + P <
Q), as shown in FIG. 4, the lid 500 is opened, and the developer enters from the buffer 200 into the developer receiving container 1.

When there is no developer in the buffer 200, the pressure Q does not act, and the lid 500 is kept closed by the urging force of the spring 502. That is, the buffer 200 is disconnected from the developer receiving container 1 by the lid 500.

Accordingly, even when a large amount of the developer remains in the developer receiving container 1, the developer is supplied even when the developer is replenished. Since the agent is stored in the buffer 200, the opening / closing lid 2 can be completely closed. Therefore, a situation in which the developer is clogged and the opening / closing lid 2 or the like comes off, or the developer replenishing container 3 does not come off does not occur. For this reason, in order to prevent replenishment when the remaining amount of the developer is sufficient, there is no need to attach a piezo-type sensor or the like, and the structure of the apparatus becomes simple and inexpensive.

When replenishing the developer, the buffer 200 is closed by the lid 500, so that the developer normally replenished in the developer receiving container 1 is supplied to the buffer 2.
It does not flow backward through 00 and leak out. Therefore, it is possible to prevent the equipment around the developer replenishing container 3 and the clothes of the worker from being stained.

In this embodiment, the torsion coil spring 5
02 is used one by one on the left and right sides, but is not of course limited to this, and may be provided on only one side if a predetermined biasing pressure is obtained.

Although the lid 500 is provided at the lower end opening 202 between the buffer 200 and the developer receiving container 1, the same effect can be obtained by providing the lid 500 at the upper opening 201 and the intermediate part.

Further, in the present embodiment, the developer replenishing container 3 is changed to the developer receiving container 3 due to the size of the area where the sheet 5 is adhered to the developer replenishing container 3 and the size of the developer replenishing device. At the time of attachment to the cover 1, the cover 300 is in a state of being pushed and opened by the opening / closing cover 2, but may be configured to be in a closed state.

[0056]

As described above, according to the present invention,
When there is no more developer in the buffer space, the third opening / closing means is closed, and the communication between the developer receiving container and the outside is cut off. Therefore, it is possible to prevent the developer from flowing backward through the buffer space and leaking to the outside when the developer is supplied.

[Brief description of the drawings]

FIG. 1A is a diagram illustrating a state of a buffer 200 when a developer replenishing container is not mounted, and FIG. 1B is a diagram illustrating a state when a developer replenishing container is mounted.

FIG. 2 is an explanatory diagram for explaining a state when the opening / closing lid 2 is closed in a state where the developer remains in a developer replenishing container.

FIG. 3 is an explanatory diagram for explaining a state in which the opening / closing lid 2 is closed with the developer remaining in the developer replenishing container.

FIG. 4 is an explanatory diagram for explaining a state when the opening / closing lid 2 is closed in a state where the developer remains in the developer replenishing container.

FIG. 5 is an explanatory diagram illustrating an opening / closing mechanism of a lid 500.

FIG. 6 is a perspective view showing an outline before a developer replenishing container is mounted on a developer receiving container.

FIG. 7 is a longitudinal sectional view of a developer receiving container equipped with a developer replenishing container.

FIG. 8 is a sectional view taken along line AA of FIG. 7;

FIG. 9 is an explanatory diagram showing a developer supply procedure.

FIG. 10 is an explanatory diagram showing a developer supply procedure.

FIG. 11 is an explanatory diagram showing a developer supply procedure.

FIG. 12 is an explanatory diagram showing a developer supply procedure.

FIG. 13 is an explanatory diagram showing a developer supply procedure.

FIG. 14 is an explanatory diagram of an operation of a lock mechanism of the developer replenishing container.

FIG. 15 is an explanatory diagram showing a state in which the opening / closing lid is closed when the developer remains in the developer replenishing container.

FIG. 16 is a diagram illustrating a detailed structure of a buffer 200.

FIG. 17 is a view for explaining a conventional problem.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 developer receiving container 2 opening / closing means (opening / closing lid) 3 developer replenishing container 4 second opening / closing means (opening / closing lid) 5 sheet 6 sheet pull-out member 200 buffer space (buffer) 201 first opening (upper opening) 202 second opening (lower opening) 500 third opening / closing means (lid) 502 biasing means (torsion coil spring)

Continuation of the front page (72) Inventor Hiroshi Hiura 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 15/08

Claims (4)

(57) [Claims] A developer receiving container having an upper opening and receiving supply of developer from a developer replenishing container; and a sliding opening / closing means for covering the upper opening.
A developer replenishing device that receives the supply of developer from the developer replenishing container with the opening and closing unit open and closes the opening and closing unit after the replenishment is completed, temporarily removes excess developer that becomes an obstacle when closing the opening and closing unit. A buffer space for temporarily storing the excess developer pushed by the opening / closing means in the buffer space; An opening, a second opening for discharging the surplus developer into the developer receiving container, and third opening / closing means for cutting off communication between the buffer space and the developer receiving container. A developer supply device, characterized in that: 2. A developer supply container, wherein a lower end opening opposite to an upper opening of the developer receiving container is formed in the developer supply container.
Sliding second opening / closing means is attached to the developer replenishing container so as to cover the lower end opening, and fixing means for fixing the developer replenishing container on the developer receiving container is provided. The developer supply device according to claim 1, wherein: 3. An urging means for urging the third opening / closing means in a closing direction with a predetermined urging force, wherein the third opening / closing means has a predetermined amount or more of developer entering the buffer space. 2. The method according to claim 1, wherein the developer is opened by its own weight to discharge the developer into the developer receiving container, and is closed after the developer is discharged into the developer receiving container. Developer supply device. 4. The third opening / closing means closes a second opening of the buffer space in conjunction with an operation of placing the developer replenishing container on the developer receiving container. The developer replenishing device according to claim 1, wherein: