Quick Release Magnetic Latch

Abstract

A latch including laterally slideable ferromagnetic members that coact with underlying stationary ferromagnetic members. The latch finds particular utility in a dual-blanket exposure station.

Parent Case Text

This is a divisional application of commonly assigned pending application Ser. No. 93,211 filed on Nov. 27, 1970 and entitled "Quick Release Magnetic Latch For Copier Exposure Station," now U.S. Pat. No. 3,694,078.

Description

BACKGROUND-SUMMARY OF THE INVENTION

This invention relates to an improved latching mechanism. It finds special utility in a copier exposure station which includes a plurality of cover sheets overlying the exposure window. Such an exposure station forms the subject of copending U. S. Patent application Ser. No. 39,757, filed May 22, 1970, the disclosure of which is hereby incorporated by reference.

In the exposure station of the aforementioned type a transparent editing blanket directly overlies the exposure window and a conventional opaque blanket overlies the editing blanket. As treated in detail in said copending application it is desirable to selectively raise the blankets individually or together. To accomplish this result great care must be taken in designing a latch to insure that it will neither mar the surface of the exposure window nor mutilate any documents that are to be copied.

All of these problems are avoided in the design of this invention. A handle is provided that includes transversely movable magnets. The magnets register with another set of magnets or ferromagnetic material such as steel when both blankets are to be raised simultaneously. By transversely moving the magnets out of registry with the corresponding magnets or ferromagnetic material the blankets may be lifted separately.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and advantages of this invention will become clearer in the following detailed description in conjunction with the drawings in which:

FIG. 1 is a top view of a latch incorporating the principles of this invention.

FIG. 2 is a front view of the latch depicted in FIG. 1.

FIG. 3 is a cross-sectional view taken along line 3--3 in FIG. 1.

FIG. 4 is a partial top view of the latch in FIG. 1 with the mechanism in a different operating position.

DETAILED DESCRIPTION

Referring now to FIG. 1 an exposure station indicated generally by the reference numeral 10 may be seen. This invention has general applicability and consequently neither has the copier been illustrated nor is the invention limited to an exposure station.

The depicted exposure station 10 includes an exposure window 12, an editing blanket 14, and an opaque cover 16. The exposure window 12 is of conventional design and is where a document to be copied is normally placed face down. The relationship of the editing blanket 14 and the opaque blanket 16 is more fully explained in copending application Ser. No. 39,757. Suffice it to say that at times it is desirable to lift both simultaneously for insertion or removal of a document and at others it is desirable to raise only the opaque blanket 16 to visually determine the registration of a document.

The preferred latching mechanism includes a U-shaped member 18. Included in the U-shaped member 18 are two transversely elongated cutouts 20. The cutouts 20 provide a means for mounting a handle 22 (omitted from FIG. 2) and a pair of L-shaped channels 24 by a set of screws 26. This assembly is movable transversely in the cutouts 20 and is spring biased rightwardly by a spring 28 connected at one end 32 to the right L-shaped channel 24 and at the other end to a post 30 that is rigidly secured to the U-shaped member 18.

Two pairs of magnets 34 are rigidly affixed to the right and left L-shaped channels 24. The magnets 34 are free to move transversely in slots 38 which are formed in the U-shaped member 18.

In FIG. 2 it is shown that the U-shaped member 18 rigidly grips the opaque cover 16. A slot 36 has been formed in the U-shaped member 18, the blanket 16 inserted and the slotted portion compressed to tightly grip the blanket 16. However, any means of affixing the blanket 16 to the U-shaped member 18 would be satisfactory.

In FIGS. 2 and 3 four magnets 40 are secured in the editing blanket 14. In the position shown in FIGS. 1-3 the four upper magnets 34 register with the four lower magnets 40. Because the magnets have faces of opposite polarity contiguous with each other the blankets 14, 16 are held together and may be raised simultaneously.

It is apparent that even though pairs of magnets have been depicted, combinations of magnets and ferromagnetic material such as iron, steel and the like could be satisfactorily utilized.

Referring to FIG. 4, the handle 22 and in consequence the magnets 34 have been moved leftwardly. Since the motion is transverse to the lines of magnetic flux such a displacement is relatively easy even for latches that have great holding strengths. Now that the corresponding pairs of magnets 34,40 are out of registry, their attractive force is nil and the opaque blanket 16 may be lifted without raising the editing blanket 14.

Thus, a new latch has been described and it is clear that many variations exist which have not been described in this preferred embodiment but are a part of the invention described in the appended claims.

Claims

The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A latching mechanism for an apparatus including a surface, first cover means for said surface pivotally attached to said surface for movement with respect thereto, and second cover means for said surface overlying said first cover, said second cover pivotally attached to said surface for independent movement with respect to said surface and said first cover, said latching mechanism comprising:

handle means slidably attached to said second cover,

carrier means mounted to said handle means for limited sliding movement relative to said second cover upon movement of said handle means;

first magnet means of a predetermined polarity mounted on said carrier;

second magnet means of a polarity opposite of said first magnetic means affixed to said first cover for selective coaction with said first magnet means;

said limited sliding movement of said carrier means being such that at one extreme thereof said first and second magnet means are contiguous with each other and at the other extreme are not contiguous with each other, whereby said second cover is adapted to be lifted from said first cover and said surface by said handle means when said first and second magnet means are not contiguous and adapted to be lifted with said first cover from said surface by said handle when said first and second magnet means are contiguous; and

an elastic means for biasing said first magnet means into said position in which said first magnet means is contiguous with said second magnet means.

2. The latching mechanism of claim 1 wherein said first and second magnet means each comprise a ferromagnetic member.