JP3149307B2 - Cassette with paper size detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cassette with a paper size detecting device provided in an image forming apparatus such as an electrophotographic copying machine, a facsimile or a printer.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrostatographic copying machine, a paper feed cassette capable of storing sheets of various sizes is sometimes provided in a detachable manner.

In such a paper feed cassette, a paper size detecting means is provided in the paper feed cassette in order for the image forming apparatus main body to detect the size of the currently stored paper.

[0004] For example, the paper size detecting means is provided with a pressing member slidably provided in contact with the free end of the paper stored in the paper cassette, and the position of the pressing member is determined by the image forming apparatus. And the like, which are detected by a plurality of detecting means provided on the main body side.

[0005]

However, in the conventional paper size detecting means as described above, switches must be provided on the main body side by the number of types of paper, so that the number of parts increases and the number of parts increases. There is also a drawback that a large space for providing a switch is required, which has been a major obstacle in reducing the size of the image forming apparatus.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a sheet feeding cassette which requires a small space for disposing a sheet size detecting means and can make the image forming apparatus compact.

[0007]

According to the present invention, means for solving the above-mentioned problems are constituted as follows. That is, a paper storage portion provided on the upper surface side of the cassette main body for storing the paper, and a long hole formed in the bottom plate of the cassette main body in the longitudinal direction of the paper stored in the paper storage portion. A sheet, which has a guide groove and a protruding shaft, which is loosely fitted in the guide groove and partially protrudes from the lower surface side of the cassette body, is provided in the paper storage portion so as to be movable along the guide groove. A pressing member that abuts a free end in the longitudinal direction of the cassette body, and a guide hole formed in a long hole shape, and is rotatably supported on the lower surface of the cassette main body. A segment gear that loosely fits the protruding shaft, an idle gear that meshes with the segment gear, is rotatably supported near the edge of the lower surface of the cassette main body, and lowers the meshing gear ratio; and a rack that meshes with the idle gear. , Said pay
In the main body of the image forming apparatus in which the paper cassette is inserted and removed
Paper size detection with multiple detection elements fixed in position
And a detecting means, which further corresponds to the plurality of sensing elements.
A plurality of detected elements are provided movably along an edge of the sheet cassette, and the pressing member is configured to
When it comes into contact with the free end, the segment gear
Meshing with the dollar gear
It is characterized by comprising comprises a serial pushing paper position sensing hand stage can move less than the displacement amount of the member.

[0008]

When the pressing member is brought into contact with the free end of the paper stored in the paper storage portion of the paper feed cassette, the meshing gear ratio is reduced from the segment gear via the idle gear, and the plurality of paper position detecting means are controlled. The detected element moves and corresponds to a plurality of detecting elements of the paper size detecting means provided in the image forming apparatus main body, and the size of the paper is detected by a combination of the elements.

Therefore, the amount of movement of the paper position detecting means with respect to the paper size detecting means may be small, and the meshing gear ratio is reduced via the idle gear to move the pressing member smaller than the displacement amount, whereby the paper is moved. The size detecting means can be made compact.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cassette with a paper size detecting device (hereinafter referred to as a cassette) of the present invention will be described in detail with reference to the drawings. 3 and 5 show the cassette 1, and FIG. 1 shows a main configuration of the cassette 1. In these figures, reference numeral 2 denotes a paper storage unit provided on the upper surface side of the bottom plate 3 of the cassette 1, and reference numerals 4 and 5 denote width regulating members for restricting the paper 6 by contacting both sides in the width direction of the paper 6. The racks 7 and 8 movably provided on the lower surface of the bottom plate 3 and the pinions 9 pivotally supported on the lower surface of the bottom plate 3 are interlocked with each other in the width direction by being fixed to the respective width regulating members 4 and 5. It is configured to be.

Reference numeral 10 denotes a pressing member which comes into contact with the rear end (free end) of the paper 6 and regulates the paper 6 in the front-rear direction. A protruding shaft 10a provided below the pressing member is formed on the bottom plate 3 in the front-rear direction. Of the protruding shaft 10a is projected downward, slides in the front-rear direction (see FIG. 2), and the base is pivoted by the pivot P fixed to the lower surface of the bottom plate 3. The protruding shaft 10a is loosely fitted in an elongated guide hole 12a formed in the shaft of the supported segment gear 12 (see FIG. 4).

Reference numeral 13 denotes an idle gear meshing with the segment gear 12, and a pivot shaft 13a fixed to the lower surface of the side of the bottom plate 3.
And a small gear 14 coaxially integrated with the rack 16 of the sheet position detecting means 15 movably provided along the side edge of the bottom plate 3. Are engaged. The paper position detecting means 15 has two detected elements 15a and 15b.

Reference numeral 17 denotes two detected elements 15a and 15b.
Contact type detection elements 17a, 17b, 1
7c, the image forming apparatus 18
The size of the paper 6 is detected and a detection signal is sent to a controller 19 (see FIG. 2). When the size is selected, the paper 6 is fed out and the photosensitive member is The image is transferred from the drum 20.

The size is detected by two detected elements 15.
a, 15b and the three detecting elements 17a, 17b, 17c, the amount of movement of the sheet position detecting means 15 is much smaller than the amount of displacement of the pressing member 10.

FIGS. 6A and 6B show the corresponding positions of the paper position detecting means 15 with respect to the paper size detecting means 17, wherein FIG. 6A shows a B4 size, FIG. 6B shows a folio size, and FIG.
4D size, (D) B5R size, (E) A5R size detection position.

As described above, the amount of movement of the paper position detecting means 15 is extremely reduced due to the reduction in the gear ratio.
The cassette 1 can be made compact, and the paper size detecting means 17 can also be made compact.
The degree of freedom in the layout of the image forming apparatus 18 can be greatly improved, and the overall size can be reduced.

FIGS. 7A to 7C show an example in which the paper size detecting means 17 is composed of two detecting elements 17a and 17b. FIG. ) Is the position where the 8.5 × 11R size is detected, and (C) is the position where the 5.5 × 8.5R size is detected.

The number of detected elements and the number of detecting elements described above may be appropriately set, and a photoelectric type paper size detecting means 1 capable of detecting the detected element in a non-contact manner instead of the contact type.
7 can also be employed.

[0019]

As described above, according to the cassette with the paper size detecting device of the present invention, the paper position detecting means having a plurality of detected elements is provided by the pressing member which abuts the free end in the longitudinal direction of the paper. With the movement amount much smaller than the displacement amount of the paper size, it is linked with the pressing member so as to correspond to the paper size detection means having a plurality of detection elements. The entire forming apparatus can be made compact.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram showing one embodiment of a cassette with a paper size detecting device of the present invention.

FIG. 2 is a perspective view of a main part of the cassette.

FIG. 3 is a plan view of the cassette.

FIG. 4 is a partial sectional view of the cassette.

FIG. 5 is a partially transparent perspective view of the image forming apparatus.

FIGS. 6A to 6E are plan views illustrating detection positions of a sheet position detection unit.

FIGS. 7A to 7C are plan views showing detection positions of sheet position detection means in different embodiments.

[Explanation of symbols]

1: cassette (cassette) with paper size detection device, 2:
Paper storage unit, 3 ... Bottom plate, 4,5 ... Width regulating member, 6 ... Paper, 10 ... Pressing member, 10a ... Protrusion shaft, 11 ... Guide groove, 1
2 ... segment gear, 12a ... guide hole, 13 ... idle gear, 15 ... paper position detecting means, 15a, 15b ... detected element, 16 ... rack, 17 ... paper size detecting means, 1
7a, 17b, 17c: detecting element, 18: image forming apparatus.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI G03G 21/16 H04N 1/00 108C H04N 1/00 108 G03G 15/00 554 (72) Inventor Masaya Murata Chuo-ku, Osaka-shi, Osaka No. 1-228, Tamazuko Mita Kogyo Co., Ltd. (56) References JP-A-2-184701 (JP, A) JP-A-63-66030 (JP, A) JP-A-4-14232 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B65H 1/00-3/68

Claims (1)

(57) [Claims] A paper storage portion provided on an upper surface side of a cassette main body for storing paper, and an elongated hole formed in a bottom plate of the cassette main body in a longitudinal direction of the paper stored in the paper storage portion. The lower part has a formed guide groove and a protruding shaft, which is loosely fitted in the guide groove and partially protrudes from the lower surface of the cassette body, and is movably accommodated in the paper storage part along the guide groove. A pressing member that abuts a free end in the longitudinal direction of the formed sheet, and a guide hole formed in a long hole shape, and is rotatably supported on the lower surface of the cassette main body. A segment gear that loosely fits the protruding shaft of the member, an idle gear that meshes with the segment gear, and is rotatably supported near the edge of the lower surface of the cassette main body to lower the gear ratio; A meshing rack and the paper cassette Forming that can be inserted and removed freely
For use with multiple sensing elements provided in a fixed position on the device body
Paper size detection means, further comprising the plurality of detection elements
And a plurality of elements to be detected, which are provided movably along the edge of the sheet cassette, and use the pressing member.
When abutting against the free end of the paper, the segment gear
Mesh with the idle gear through the idle gear
Paper size detecting device with a cassette characterized by comprising comprises a <br/> sheet position detecting hand stage can move less than the displacement amount of the pressing member by.