GB2119770A

GB2119770A - Paper feeding apparatus

Info

Publication number: GB2119770A
Application number: GB08312356A
Authority: GB
Inventors: Hiroaki Ura; Takashi Tamura
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 1982-05-10
Filing date: 1983-05-05
Publication date: 1983-11-23
Also published as: JPS58197136A; GB8312356D0; DE3316721A1

Abstract

A paper-feeding system having an improved paper feeding rack for electrophotographic copying apparatus wherein a paper-feeding cassette (A) for storing a pile of recording papers can be removably mounted on the rack. A cam (14) is formed on the bottom wall (10) of the paper-feeding cassette (A) to cooperate with a follower in the form of a flange (16) formed on a pusher member (5) which urges upwardly a bottom plate of the paper feeding cassette supporting the papers, such that when the paper-feeding cassette (A) is withdrawn from the paper- feeding rack, the cam (14) and flange (16) are brought into engagement to cause depression of the pusher member (5) to allow complete withdrawal of the cassette from the rack. Thus, withdrawal of the cassette can take place even if pusher member (5) is being held in the upwardly-urged position after e.g. power supply has been interrupted. <IMAGE>

Description

SPECIFICATION Paper feeding apparatus The present invention has been devised with feeding apparatus for example of an electrophotographic copying machine and more particularly to a paper-feeding apparatus of the type wherein paper is fed with a bottom plate in the paper-feeding cassette, in which recording paper (sheets of paper) are loaded, being pushed in automatically.

Many of the paper-feeding sections of electrophotographic copying machines are of the type wherein paper is fed with a bottom plate in the paper-feeding cassette being pushed up towards a paper-feeding unit such as a paperfeeding roller or the like. In paper-feeding apparatus with such construction a pusher member needs to be removed from the paperfeeding cassette when the paper-feeding cassette is attached to or detached from the paper-feeding rack. Previously, therefore, a manually-operated lever that depresses the pusher member has been provided on the paper-feeding rack and such manually-operated lever has been operated each time a paper-feeding cassette is loaded or removed from the rack. The necessity to operate the manually-operated lever is inconvenient.Even where a manually-operated lever is not used, an operating member that separately removes the pusher member is still needed.

In order to solve these problems, the present applicants have suggested a paper-feeding apparatus with a structure as shown in Fig. 1 and disclosed in U.S. Patent Application No. 386,624.

In this paper-feeding apparatus, there is provided a paper-feeding unit 4 consisting of a paperfeeding belt 2 and a separating member 3 at the back of the paper-feeding rack 1 where the paperfeeding cassette A is attached. Under the paperfeeding rack 1, there is provided a pusher member 5 which is in the position shown in the solid lines each time the signal for commanding paperfeeding, is sent out. Therefore, such paper-feeding system has an advantage that the paper-feeding cassette A may freely be loaded or removed when no signal for commanding paper-feeding exists, because the pusher member 5 is then retracted under the paper-feeding rack 1.

With such constitution, however, if the operation of the apparatus is discontinued during a paper-feeding operation for some reason, such as when a plug for power source is carelessly pulled out from its socket or when there is a power failure or the like, the pusher member 5 would be held in its upwardly extending position so that it is impossible to withdraw the paper-feeding cassette A from the paper-feeding rack 1.

The present invention has been devised with the purpose of overcoming the abovementioned problems.

The present invention provides a paper-feeding apparatus comprising a pusher member for automatically urging upwardly a bottom plate of a paper-feeding cassette against a paper-feeding unit, and in which recording paper is removed from the paper-feeding cassette when inserted into a paper-feeding rack, wherein a cam is provided on said paper-feeding cassette and a follower for cooperation with said cam is provided on said pusher member; the arrangement being such that, when said paper-feeding cassette is withdrawn from the paper-feeding rack, the cam follower cooperate so as to cause the pusher member to be lowered to allow complete withdrawal of the cassette.

According to the present invention, it is possible freely to withdrawn completely the paper-feeding cassette even if the plug of a power source is pulled our carelessly during paper feeding or power failure takes place or the apparatus is halted for some other reason. It is an advantage of an apparatus according to the present invention that the operational function of the paper-feeding apparatus in which the bottom plate of the paper-feeding cassette is pushed up automatically, can be fully utilized and the system can be provided at low cost because the construction is extremely simple.

In the drawings:- Fig. 1 is a sectional view of a previously proposed paper-feeding apparatus; Fig. 2 is a sectional view of a paper-feeding apparatus according to the present invention; and Fig. 3 is a perspective view of primary portions of the paper-feeding apparatus of Fig. 2.

An embodiment of the present invention will now be described by way of example and with reference to Fig. 2 and Fig. 3.

Fig. 2 is a sectional view corresponding to Fig.

1 showing a paper-feeding system according to the present invention and the same symbols are given to the structural portions which are common to Fig. 1 and Fig. 2.

According to this embodiment of the present invention, the opening 11 for accepting the pusher member 5 is formed in the bottom wall 10 of the paper-feeding cassette A and this opening 11 is connected to an opening 13 in the front wall 12 of the paper-feeding cassette A as shown in Fig. 3.

The bottom wall 10 of the paper-feeding cassette A has a cam 14 projecting from the aforesaid opening 11 and a driven follower in the form of a flange 1 6 that is formed by bending a part of the pusher member 5 downwardly is positioned to be engaged by a cam surface on the cam 14 when the paper-feeding cassette A is withdrawn from the apparatus. A spring is employed for urging the pusher member 5 upwardly and the engagement of the cam with the flange 16 causes downward movement of the pusher member 5 against the action of the spring.

With this structure, the paper-feeding cassette A may be withdrawn in the direction of the arrow X in Fig. 2, when a plug for a power source is pulled out carelessly from its socket during paper feeding or a power failure takes place and the pusher member 5 is held in the position shown with a solid line in Fig. 2.When a flange 1 6 is engaged with the cam 14 when the paper-feeding cassette A is being removed, the pusher member 1 5 is depressed to the position shown by chain dotted lines in Fig. 2, against the action of the aforesaid spring and therefore the roller 1 7 located at the tip of the pushing up member 5 is brought to a position in which it can pass through the opening 13 in the front wall of the paperfeeding cassette A so that the paper feeding cassette A can be completely withdrawn from the paper-feeding rack 1.

Modifications of this embodiment can be made within the scope of the invention as defined in the accompanying claims. For example, it is also possible to provide an apparatus in accordance with the invention, in which a cam surface is provided, if occasion demands, in the vicinity of the opening of a front wall of the cassette and the driven surface of the pusher member is engaged by that cam surface. In such an embodiment, it is desired to set the rotary axis of the pusher member in a forward position further from the front wall of a paper-feeding cassette. It is also of course possible that the contact portion with the bottom plate namely the end of the pusher member may be provided as an arm or other forms as well as the roller described above.

Claims

1. A paper-feeding apparatus comprising a pusher member for automatically urging upwardly a bottom plate of a paper-feeding cassette against a paper-feeding unit, and in which recording paper is removed from the paper-feeding cassette when inserted into a paper-feeding rack, wherein a cam is provided on said paper-feeding cassette and a follower for cooperation with said cam is provided on said pusher member; the arrangement being such that, when said paper-feeding cassette is withdrawn from the paper-feeding rack, the cam and the follower cooperate so as to cause the pusher member to be lowered to allow complete withdrawal of the cassette.

2. A paper-feeding apparatus as claimed in Claim 1 , wherein the cassette is formed with an aperture in its bottom wall through which the pusher member can project and an adjoining opening in a front wall thereof for passage therethrough of the pusher member in a lowered position thereof.

3. A paper-feeding apparatus as claimed in Claim 1 or Claim 2, wherein said cam is provided on a bottom wall of said paper-feeding cassette.

4. A paper-feeding apparatus as claimed in Claim 3, wherein said follower is a downwardly turned flange provided on the pusher member to cooperate as aforesaid with said cam which projects downwardly of the bottom wall of the cassette.

5. A paper-feeding apparatus as claimed in Claim 2, wherein said cam is provided adjacent said front wall of the cassette.

6. A paper-feeding apparatus as claimed in any preceding Claim, wherein said pusher member having said driven follower is biassed upwardly and is pivotally mounted.

7. A paper-feeding apparatus substantially as hereinbefore described with reference to, and as illustrated in, Figures 2 and 3 of the accompanying drawings.