MEDIA-FEED ASSEMBLIES

Abstract

Media-feed mechanisms for business machines are provided. A media-feed mechanism comprises a frame, a stopper, a rotary member, and a swing gear mechanism. The rotary member comprises a cam contacting the stopper and a driven gear fixed to the cam. When the gear mechanism is in a first position, a first gear thereof engages the driven gear and rotates the cam in a first direction, to impel the stopper from a first angle to a second angle. When the swing gear mechanism is in a second position, a second gear thereof engages the driven gear and rotates the cam in the first direction, such that the stopper rotates from the second angle to the first angle.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates in general to media-feed assemblies and in particular to media-feed assemblies preventing accidental feeding of multiple sheets.

2. Description of the Related Art

Referring to FIG. 1, a conventional media-feed assembly of a business machine primarily comprises a tray 12 with a sheet stack (not shown) disposed therein, a separator 14 on the bottom of the tray 12, a shaft 16, a feed arm 18, and a feed roller 19 at an end of the feed arm 18. As shown in FIG. 1, the feed arm 18 is pivotally connected to the shaft 16, and the shaft 16 is mounted to the side walls of the tray 12.

Generally, the sheet stack is pressed and fed by the feed roller 19, wherein the feed arm 18 is rotatable around the shaft 16 to adjust the angle thereof for feeding sheets of various thicknesses. When feeding, the lower sheets of the sheet stack are buckled by the separator 14, and only the top sheet is fed. However, when the sheets are improperly disposed in the tray 12 and exceed the separator 14, accidental feeding of multiple sheets may occur.

BRIEF SUMMARY OF THE INVENTION

Media-feed mechanisms for business machines are provided. A media-feed mechanism comprises a frame, a stopper, a rotary member, and a swing gear mechanism. The rotary member comprises a cam contacting the stopper and a driven gear fixed to the cam. When the gear mechanism is in a first position, a first gear thereof engages the driven gear and drives the cam rotating in a first direction, to impel the stopper from a first angle to a second angle. When the swing gear mechanism is in a second position, a second gear thereof engages the driven gear and drives the cam rotating in the first direction, such that the stopper rotates from the second angle to the first angle.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

FIG. 1 is a perspective diagram of a conventional media-feed assembly;

FIG. 2 is a perspective diagram of an embodiment of a media-feed assembly;

FIG. 3 is a perspective diagram of an embodiment of a stopper;

FIG. 4 is a perspective diagram of a first gear engaged with a driven gear;

FIG. 5 is a perspective diagram of a first gear disengaged from a driven gear when meeting a toothless potion thereof;

FIG. 6 is a perspective diagram of a second gear engaged with a driven gear; and

FIG. 7 is a perspective diagram of a second gear disengaged from a driven gear when meeting a toothless potion thereof.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 2, a media-feed assembly of a business machine primarily comprises a frame H, a stopper 51, a rotary member 61, and a swing gear mechanism 71. In this embodiment, the stopper 51, the rotary member 61, and the swing gear mechanism 71 are pivotally connected to the frame H. The frame H comprises a tray 41 with a sheet stack S disposed therein. The top sheet S1 of the sheet stack S is fed by a roller connected to the frame H, such as the feed roller 19 shown in FIG. 1, along a feeding direction A. The stopper 51 is rotatable with respect to the frame H to selectively guide or block the sheets, preventing feeding of multiple sheets.

As shown in FIG. 3, the stopper 51 comprises a shaft 51a pivotally connected to the frame H and a contact portion 51b extending from the shaft 51a, wherein the contact portion 51b has a nub 51c, such as an elastomer. Referring to FIG. 4, the rotary member 61 comprises a cam 61a and a driven gear 61b fixed to the cam 61a. In this embodiment, the cam 61a and the driven gear 61b are monolithically formed in one piece, and the driven gear 61b comprises an irregular toothless portion 61b′. Specifically, the driven gear 61b and the cam 61a are rotatable around a central axis C thereof, and the nub 51c maintains contact with an outer surface of the cam 61a.

As shown in FIG. 4, the swing gear mechanism 71 comprises an arm 72, a driving gear 73, a first gear train 74, and a second gear train 75, wherein the driving gear 73 and first and second gear trains 74 and 75 are rotatably connected to the arm 72. As shown in FIG. 4, the first and second gear trains 74 and 75 are engaged with the driving gear 73 from opposite sides thereof, wherein the first gear train 74 has a first gear 741, and the second gear train 75 has two second gears 751. In some embodiments, the first gear train 74 may have an odd number (such as three or five) of first gears 741, and the second gear train 75 may have an even number (such as four or six) of second gears 751.

In FIG. 4, the contact portion 51b and the sheets S form an included angle α, and the sheets S are blocked by the contact portion 51b from falling along direction A. When feeding the sheets S, the swing gear mechanism 71 rotates to a first position as shown in FIG. 4, such that the first gear 741 at the end of the first gear train 74 engages with the driven gear 61b of the rotary member 61. Subsequently, with clockwise rotation of the driving gear 73, the driven gear 61b and the cam 61a are rotated along a first direction A1 (clockwise), such that the contact portion 51b descends from the angle α to the angle β (shown in FIG. 5), wherein β>α.

When the contact portion 51b rotates to the angle β, as shown in FIG. 5, the first gear 741 meets the toothless portion 61b′ and disengages from the driven gear 61b, such that the contact portion 51b is held in the angle β. Hence, the top sheet S1 of the sheet stack S can be fed by the feed roller.

After feeding, the swing gear mechanism 71 is reversely rotated with the driving gear 73 (counterclockwise) from the first position to a second position, as shown in FIG. 6, such that a second gear 751 at the end of the second gear train 75 is engaged with the driven gear 61b. Similarly, the cam 61 of the rotary member 61 is driven to rotate along the first direction A1 (clockwise) until the second gear 751 meets the toothless portion 61b′, as shown in FIG. 7, such that the contact portion 51b is lifted to the angle α.

With rotation of the rotary member 61 along the first direction A1, the contact portion 51b returns from the angle β shown in FIG. 6 to the angle α shown in FIG. 7. Here, the swing gear mechanism 71 is disengaged from the driven gear 61b when the second gear 751 meets the toothless portion 61b′, such that the contact portion 51b can be held in angle β to block the sheets S from falling along the direction A.

To switch the media-feed assembly from the state shown in FIG. 7 to the state shown in FIG. 5 for feeding, first, the swing gear mechanism 71 is reversely rotated with the driving gear 73 (clockwise) and returned from the second position to the first position shown in FIG. 4. Subsequently, the cam 61a is driven by the first gear 741 to rotate along a first direction A1 (clockwise), such that the contact portion 51b descends from the angle α to the angle β, as shown in FIG. 5.

Media-feed assemblies are provided according to the embodiments. When the swing gear mechanism 71 is in the first position, the driving gear 73 rotates the cam 61a along the first direction A1, such that the contact portion 51b of the stopper 51 descends from the angle α (shown in FIG. 4) to the angle β (shown in FIG. 5). Alternatively, when the swing gear mechanism 71 is in the second position, the driving gear 73 rotates the cam 61a along the first direction A1, such that the contact portion 51b of the stopper 51 is lifted from the angle β (shown in FIG. 6) to the angle α (shown in FIG. 7). Specifically, when the first gear 741 or the second gear 751 meets the toothless portion 61b′ of the driven gear 61b, the swing gear mechanism 71 is disengaged from the driven gear 61b, such that the contact portion 51b can be selectively held in the angle α or the angle β, to prevent accidental feeding of multiple sheets.

While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.

Claims

1. A media-feed assembly of a business machine, comprising:

a frame, comprising a tray with at least one media sheet disposed therein;

a stopper, pivotally connected to the frame and rotatable with respect to the media sheet between a first angle and a second angle;

a swing gear mechanism, pivotally connected to the frame, comprising a driving gear, a first gear train, and a second gear train, wherein the first and second gear trains are engaged with the driving gear; and

a rotary member, comprising a cam contacting the stopper and a driven gear fixed to the cam, the driven gear comprising an irregular toothless portion, wherein when the swing gear mechanism is in a first position, the first gear train is engaged with the driven gear, to rotate the cam along a first direction and impel the stopper from the first angle to the second angle, and when the swing gear mechanism is in a second position, the second gear train is engaged with the driven gear, to rotate the cam along the first direction and return the stopper from the second angle to the second angle.

2. The media-feed assembly as claimed in claim 1, wherein when the first gear train meets the toothless portion of the driven gear, the swing gear mechanism is disengaged from the driven gear, and the stopper is held in the second angle.

3. The media-feed assembly as claimed in claim 1, wherein when the second gear train meets the toothless portion of the driven gear, the swing gear mechanism is disengaged from the driven gear, and the stopper is held in the first angle.

4. The media-feed assembly as claimed in claim 1, wherein the stopper comprises a shaft pivotally connected to the frame and a contact portion in contact with the cam.

5. The media-feed assembly as claimed in claim 4, wherein the contact portion comprises a nub in contact with the cam.

6. The media-feed assembly as claimed in claim 5, wherein the nub is an elastomer.

7. The media-feed assembly as claimed in claim 1, further comprising a feed roller connected to the frame, wherein the media sheet is fed by the feed roller when the stopper is in the second angle.

8. The media-feed assembly as claimed in claim 7, wherein the media sheet is blocked from feeding by the stopper when the stopper is in the first angle.

9. The media-feed assembly as claimed in claim 7, wherein the second angle exceeds the first angle.

10. The media-feed assembly as claimed in claim 1, wherein the first gear train comprises an odd number of first gears, and the second gear train comprises an even number of second gears.

11. The media-feed assembly as claimed in claim 1, wherein the swing gear mechanism further comprises an arm with the first and second gear trains rotatably connected thereto.

12. The media-feed assembly as claimed in claim 1, wherein the swing gear mechanism is moved between the first and second positions with the driving gear.

13. The media-feed assembly as claimed in claim 1, wherein the driven gear and the cam are monolithically formed in one piece.