JPS63106246A - Sheet feeding device - Google Patents

Abstract

PURPOSE:To feed the sheet from the first to the last in stable ways by forming a sheet loading base into the form which permits the contact of the top edge of the loading base with the outer periphery of a paper feeding roller, at the max. rising position. CONSTITUTION:The top edge part of a sheet loading base 56 swings around the rear edge part as center. In particular, each shaft supporting position of the pins 64 and 65 is set so that the top edge contacts a paper feeding roller 31 at the highest rising position, i.e., the contact position with the paper feeding roller 31. Further, the top edge 56a of the sheet loading base 56 is formed into the projection form where the part opposed to the peripheral edge 31e of the paper feeding roller 31 projects in the paper supply direction. A stacker 30 is urged to the paper feeding roller 31 side by a leaf spring guide installed onto a device frame, and at the same time, a projection 59 is projected from the stacker 30, and collided with the revolution shaft 31a of the paper feeding roller 31, and the paper feeding gap G is kept.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a sheet feeding device that separates and supplies paper, cards, and other sheets that have been pre-loaded and stored one by one to the main bodies of various processing devices such as printers, printing machines, and copiers.

[Conventional technology]

In general, as a method for separating and feeding stacked sheets of paper, plastic, etc. one by one from the top, the top sheet on a stacker (sheet stacker) is fed out by a paper feed roller that engages with it, and at the same time, A mechanism that separates and feeds relatively thick sheets, such as postcards and other cards, is used as a simple paper feeding mechanism that separates and feeds sheets with a gap for one sheet prepared on the downstream side of the paper feed. Then, after the top sheet is sent out, a sheet loading platform is always equipped with a spring or the like so that the remaining sheet engages with the paper feeding roller, and the sheet loading platform 103 is placed inside the sheet storage frame 102 so as to face the feeding roller 101. Installed so that it can be raised and lowered freely. The stacker 103 is always urged upward by springs 104 and 105, and a tip end abutting piece 107 of the sheet 106 is provided in front of the paper feed roller 101 to allow only the top sheet to advance and to prevent the second and subsequent sheets from advancing. A gap G corresponding to one sheet is formed between the paper feed roller 101 and this abutment piece 107 to prevent this. Such conventional devices have the following drawbacks. If two or more paper feed rollers 101 are arranged at a distance in the width direction of the sheet in order to apply a uniform feeding force in the width direction of the sheet 106 to obtain stable separation, the center of the sheet may be disposed between the rollers. It tends to rise and become curly or wavy. This is due to the fact that there is an air layer between the stacked sheets, and if you press this from the top, the middle part naturally lifts up. However, with thick paper, plastic sheets, etc., this curling or waving phenomenon may occur due to non-feed or double feed. It causes・In other words, when the loaded amount of sheets is large as shown in Figure 6 (B), the degree of curl is large and the feeding force of the paper feed roller is strong, and when the amount of sheets is reduced as shown in Figure 6 (C), the sheets change to the shape of the loading table. As a result, the degree of curling becomes smaller and a weaker feeding force is applied. Therefore, if the paper feed separation conditions such as the gap size and the pressure contact force between the paper feed roller and the sheet are set based on the condition shown in (B), reliable separation will not be obtained in the condition shown in (C). If the opposite is true, reliable separation cannot be expected in the state shown in (b) figure. In particular, if you print on a cardboard card such as a postcard using a regular typewriter or printer, and then place it on the sheet tray to print on the back of the card, the space between the sheets will be larger than expected, resulting in non-feed or skew. occurs frequently, resulting in unbearable results for array use.

[Purpose of the invention]

In view of the above, the present invention enables sheets set on a loading table to be engaged with paper feed rollers in a substantially uniform posture and state regardless of the size of the loaded sheet, even if it is a thick paper sheet such as a card, so that the sheet can be kept in a stable posture. The object of the present invention is to provide a sheet feeding device which can feed sheets to a feeding gap set in advance by caulking, and thus can stably feed sheets from the first sheet to the last sheet with a simple structure.

[Solution]

In order to achieve the above object, the present invention first sets the shape of the sheet loading platform so that the leading edge of the loading platform comes into contact with the outer periphery of the paper feed roller when the loading platform is at its maximum elevation (no sheet). The leading edge of the stacker facing each peripheral edge of the zero-order paper feeding roller is constituted by a protrusion protruding in the paper feeding direction. In other words, a sheet feed roller connected to an appropriate driving means, a vertically movable sheet loading table that pushes up and presses stacked sheets onto the sheet feeding roller, and a sheet loading table that engages with the leading edge of the sheet on this sheet loading table to The leading edge of the sheet mounting base made of a paper roll plate is shaped so that it comes into contact with the outer periphery of the paper feed roller at the highest position, and the sheet mounting base is shaped so that it contacts the outer periphery of the paper feed roller at the highest position, and the sheet mounting base faces the respective peripheral edges of at least the two left and right paper feed rollers. A solution to this problem is that the leading edge of the stand is shaped like a protrusion that protrudes in the paper feeding direction.

[Effect]

Feed rollers placed at two or more locations on the left and right sides in the sheet feed width direction provide almost uniform feeding over the entire length of the sheet in the width direction, preventing sheet inclination and so-called skew. The paper feed roller is pushed up at the position where it comes into contact with the sheet, resulting in strong engagement between the paper feed roller and the sheet. Also, when the number of sheets on the loading platform decreases, the undulation due to the bulge of the sheets between each paper feed roller tends to become smaller compared to when the loading amount is large, but the edge of the roller periphery is formed with protrusions that protrude in the paper feeding direction, and the stack is fed out in a uniform posture.

【Example】

The illustration shows a case in which a sheet feeding device B is detachably attached to a printing machine main body A consisting of a printer.The printing machine main body A is a normal thermal transfer printer, and a printing unit P backs up a sheet S. A platen 1, a printing element 2, a carriage 3 that moves the printing element 2 step by step at each character interval, a platen paper feeding mechanism 4 that steps the sheet S at the position of the platen 2 in the row direction, and this paper. It is composed of a driving machine body M of the feeding mechanism,
The printing element 2 prints on the sheet in response to a printing signal output from a computer or an input key, and the carriage 3 is moved step by step according to the character spacing to execute the next printing. - When printing for a line is completed, the paper feed mechanism 4 is operated to step feed the sheet to the next line. 2. This platen 2 is composed of a shaft-like stem member positioned in the paper width direction, and its surface facing the sheet is formed of an elastic material such as rubber. A U-shaped paper path 7 is constructed around the platen 2, and the sheet is taken in from the paper feed port 7a at one end, printed on the platen 2, and then ejected from the paper discharge lower b at the other end. It has become. The paper path 7 is provided with a platen paper feeding mechanism 4 that supplies sheets to the platen portion and simultaneously feeds the sheets in steps at the platen portion as follows. In the illustrated example, since the platen 2 has no paper feeding function, a paper feeding roll 8 is rotatably supported on the frame 6 in addition to the platen 2 and adjacent to the platen 2. One end is connected to the drive motor M by a gear transmission mechanism 9, and at the same time, the other end is a knob 1 for manual rotation.
The zero pinch rollers 12 and 13 are in pressure contact. These pinch rollers 12 and 13 are arranged in two rows near the paper feed lower a and near the platen 2, and are fixed to the frame 6 with screws 15 so as to be in constant pressure contact with the paper feed roll 8 side by a leaf spring holder 14. It is. The carriage 3 is movable left and right in the paper width direction, and its rear end 3a is fitted into a guide rail 16 of the frame 6, and its tip 3b is fitted into a shaft 17 attached to the frame. Although not shown, the rack is fixed to an endless wire passed through pulleys provided at the left and right ends of the platen 2 as usual, and a stepping motor is connected to one of the pulleys. Therefore, a printing element 2 consisting of a thermal head is swingably attached to the carriage 3 on a shaft 19 so that it comes into contact with the platen 3 during printing and separates when not printing. It is equipped with
The tape is wound up in response to the movement of the carriage 3 in the printing direction. A paper sensor 20 (not shown) is arranged in the paper feed path 7, detects the trailing edge of the sheet S that is being printed, determines the last line to be printed, stops the printing operation, and at the same time starts the paper feed roll 8. The paper is rotated by a predetermined amount and the paper is ejected from the paper ejection lower b. The platen paper feed mechanism 4 in the illustrated embodiment is composed of a shaft member to which the platen 3 is fixed, and a paper feed roll 8 is provided near the shaft member.
However, instead of this, the platen itself is made up of a rotatable roll-shaped member, and after the pinch roller is pressed, a drive motor is connected to this roll-shaped platen, and the paper is fed by rotation of the platen. There may be. Furthermore, although a thermal transfer head is shown as a printing element,
This is just an example, and the same applies regardless of whether the head is a dot impact head, a thermal head, an inkjet head, an electrostatic head, etc.
It is configured as a paper feed/discharge unit B that automatically supplies the sheets S to the paper feed lower a of the printing machine main body A together with a paper discharge device that guides and stacks and accommodates the sheets. This paper feed/discharge unit B is provided with a paper feed stacker 30 and a paper discharge stacker 21 in a machine frame 22 at a position connected to a paper feed lower a and a paper discharge lower b of a printing machine main body A, and a frame 6 of the printing machine. It can be detachably attached to. First, the paper discharging device includes a paper discharging roller 25 arranged near the paper discharging lower b of the printing machine A, a guide cover 26 that can be opened and closed and facing the paper discharging roller 25 and guiding the sheet to the paper discharging stacker 21. Particularly, the paper discharge stacker 21 is composed of a paper trailing edge receiving part 21a, a back receiving part 21b, and a manual feed slit 27 into which the paper is inserted through the gap shown in the illustration between the paper rear end receiving part 21b and the paper receiving part 21b. It is. This manual feed slit 27 is located at the paper feed lower a of the printing machine main body A.
A path 28 is provided so that a manually fed sheet can be fed to the pressure contact point between the paper feed roller 8 and the pinch roller 12. A paper ejection path 29 from the paper ejection lower b of the printing machine main body A to the paper ejection stacker 21 is formed between the paper ejection roller 25 and the guide cover 26. The driving device (drive motor M shown in the drawing) of the platen paper feeding mechanism 4 transmits the power, and the paper is ejected at the same speed as the paper conveyance speed of the platen paper feeding mechanism 4. Next, the sheet feeding device includes a sheet feeding stacker 30 and a sheet feeding roller 31 that engages with the topmost sheet of the sheets S stacked and stored in this sheet feeding stacker 30. It is composed of a paper feed path 32 that guides the sheet S fed out by the paper feed roller 31 between the paper feed roll 8 of the platen paper feed mechanism 4 and the pinch roller 11. The paper feed stacker 30 is attached to a device frame 33 as shown in FIG. 2.4. This device frame 33 has a pair of left and right side plates 33a. 33b and a bottom plate 33c that connects the two side plates, and these left and right side plates have rotating shafts 31a and 25a of the paper feed roller 31 and the paper discharge roller 25, and their transmission gears 34.
, 35, 36, 37° 38, At the same time that the chucking member 39 is attached to the printing machine and the paper feed stacker 30 is attached to the bottom plate 33c, the sheet is moved to the paper feed lower a.
It also serves as a guide (portion 33g shown in the figure) that leads to. The rotating shaft 3 attached to the left and right side plates 33a and 33b
1a is equipped with a paper feed roller 31, and is connected to the drive motor M of the platen paper feed mechanism 4 on the printing machine main body side by a gear transmission shown in FIG. , the paper feed roller 31, the platen paper feed roller 8, and the paper discharge roller 25 are configured to rotate integrally at the same timing. 1.-) The drive motor wheel 9 built into the main body A of the printing machine
The gear 34 of the sheet feeding device B meshes with the gear 34, and the rotation is transmitted from the gear 34 to the rotating shaft 25a of the paper discharge roller 25 through the gear 35.
Similarly, the signal is transmitted from the gear 34 to the rotating shaft 31a of the paper feed roller 31 via gears 36, 37, and 38. The paper feed roller 31 is composed of two or more rollers spaced apart from each other in the width direction. The one shown is 3, the one shown is 3
It consists of ke. This is in order to be able to feed various types of paper with different paper thicknesses and widths by replacing the paper feed stacker 30, which will be described later. The positional relationship between the paper width and the rollers is selected so that paper with a small width size is fed by two rollers. A mounting space 40 for a paper feed stacker is prepared between the paper feed roller 31 and the bottom opening 33c of the device frame 33, and the bottom plate 33c has a space 40 for mounting a paper feed stacker in the paper feed direction. A leaf spring guide 44 approaching the paper roller 31 is the attachment. This leaf spring guide 44 is constructed of an inclined plate-like member so as to serve as a guide when the stacker is attached because the illustrated paper feed stacker 30 attaches and detaches a plurality of parts depending on the sheet size, and also serves as a guide when the paper feed stacker 30 is attached to the stacker. A spring action is applied to urge the tip end of the paper toward the paper feed roller 31 side. Therefore, a paper feed stacker as shown in FIG. 2 is inserted into the stacker mounting portion 40 along this plate spring guide 41, and the hook formed on one side of the bottom plate 33c and the stacker 30 is connected to the stop protrusion 42 and the hook formed on the other side. When the stacker 30 is fitted with the stopper hole 43, the stacker 30 is held in the machine frame 33 so as to be able to swing freely around the stopper portion. To explain the case where the present invention is adopted in such an apparatus, the paper feed stacker of the present invention does not necessarily have to have a detachable and replaceable cassette structure, but it can be done as shown in FIG. 3.4. Regarding paper feed stacker. The paper feed stacker 30 includes a sheet storage frame 55 and a sheet mounting table 56 arranged vertically movably inside the storage frame 55.
It is composed of a spring 57 that always urges this platform 56 upward, that is, toward the paper feed roller 31 side, and a tip abutment piece that engages with the leading edge of the sheet stored on the sheet platform 56. be. This paper feed stacker is installed by inserting it into the cassette mounting space 40 prepared in the device frame 33 along the aforementioned leaf spring guide 41, and at the same time forming a protrusion 51 provided at the bottom of the stacker on the bottom plate 33c of the machine frame 33. It is designed to be inserted in line with the notch groove 52 which is the opening. In this case, the notched groove 52 guides the left and right positions of the stacker, and the leaf spring guide 41 guides the top and bottom positions of the stacker. When the paper feed stacker 30 is completely inserted into the mounting space 40, the positioning pieces 53 and 54, which are hooks provided on the stacker, are fitted to the rotating shaft 31a of the paper feed roller 31, and the paper feed stacker is moved to the position shown in FIG. It is held stationary in the state. Therefore, the sheet feed stacker 30 includes a sheet storage frame 55, a sheet loading table 56 disposed vertically movably inside the sheet storing frame 55, a spring 57 that always urges this loading table upward, and a The front end abutting piece 58 is configured to engage with the leading edge of the sheet stored in the sheet.
The positioning pieces 53 and 54 provided on the left and right sides of the stacker 30 control the rotation of the paper feed roller 31 so as to form a paper feed gap G corresponding to the thickness of one sheet between the stacker 30 and the paper feed roller 31. The positional relationship is maintained by engaging with the shaft 31a. Therefore, the storage frame 55 has a pair of left and right side plates 62, 63 and a bottom plate 50 integrally formed with synthetic resin.
．． The above-mentioned positioning protrusions 53 and 54 extend from each of the left and right side plates 63, and the width of the storage frame is adjusted to match the horizontal position so that the end abutting piece can be stored in the vertical position.
．． At the same time as setting the interval 63, the guide side plate 5
5a is provided by fitting a bent piece 55c into a guide groove 55b formed in the bottom plate 50 so as to be able to swing freely. Therefore, in the state shown in FIG. 4, the guide side plate 55a holds the postcard in a horizontal position between it and the side plate 62, and by adjusting the movement of this guide side plate to the right side, the postcard is also held in the vertical position between it and the side plate 62. It looks like this. The bottom plate 5 is provided between the platform 56 and the storage frame bottom plate 50.
The spring 57 supported at zero always urges the platform 56 upwards.
It is formed integrally with the storage frame 55 so as to lock the leading edge of the paper stored in the storage frame 55 and at the same time form a gap G corresponding to the thickness of one sheet of paper between the paper feed roller 31 and the paper feed roller 31. In particular, the paper feeding gap shown in FIG. 1 is formed because the shape of the paper fed out by the paper feeding roller in the width direction is most stable at the center of the paper feeding roller. As described above, the tip of the sheet platform 56 swings around its rear end as the axis, but in particular, the sheet platform 56 is at the highest position as shown in FIG. The bearing positions of the bins 64 and 65 are set so that their leading edges abut against the roller at the position where they are in contact with the roller. At the same time, the tip 1Ik56a of the sheet mounting table 566 is formed in the shape of a protrusion that faces the peripheral edge 31a of the paper feed roller 31 and protrudes in the paper feeding direction. In other words, the fourth
The portions 60 and 61 in FIG. A holder piece that protrudes above the platform 56,
Positioning pieces 53 and 54 provided on the left and right sides of the stacker engage with the rotating shaft 31a of the paper feed roller as shown in FIG. 3 so as to form a paper feed gap G in which a spring 57 acts on the stored paper. The position is determined by Therefore, the storage frame 55 has a pair of left and right side plates 55a and 55b, and a bottom opening 50.
In this case, when the paper feed stacker 30 does not need to be detachable, the paper feed stacker 30 is assembled and fixed in the device frame 33. The paper feed roller 31 and the tip abutment piece 58
When installing the paper feed gap G, the paper feed gap G can be maintained by adjusting the position. The position of the tip end abutting piece 58 and the paper feed roller 31 may be guaranteed by the method shown in FIG. In other words, the stacker 30 is biased toward the paper feed roller 31 by the plate spring guide 41 provided on the device frame 33, and at the same time, a protrusion 59 (as shown in FIG.
The paper feed roller 31 is
In this method, the paper feed gap G is maintained by abutting against the rotating shaft 31a and the paper feed gap G. The sheet mounting table 56 is formed of a plate-like member, and its leading edge in the sheet feeding direction is set in a shape such that it comes into contact with the outer periphery of the sheet feeding roller 31 at the highest position (no-sheet state MA). This can be easily configured by selecting the illustrated dimensions of the sheet loading platform 56, but a normal sheet loading platform extends sufficiently long forward in the paper feeding direction relative to the position of the sheet feeding roller, and the sheet loading platform is placed at the highest position. While the platform is designed to engage the paper feed roller with its flat surface at its leading end, this arrangement is such that the leading edge 56a of the platform 58 comes into contact with the outer periphery of the paper feeding roller 31, as will be described later. This is to bring out the effect of the protrusion. Therefore, the leading edge 56a of the sheet mounting table 56 is connected to the paper feed roller 3.
The protrusion shape 60.61 protrudes in the paper feeding direction at a position facing the peripheral edge 31e of the paper sheet 1. In other words, the leading edge 56a of the sheet platform 56' is connected to the paper feed roller 3.
1 central part 31. The peripheral edges 31, -) 1e protrude in the sheet feeding direction from c to back up the sheets on the table. In the case shown in the figure, this protrusion 60.61 is provided on the left and right two paper feed rollers 31, facing the inner center edge edge of each roller, and when the sheet is fed out by the symmetrical protrusion 60. This ensures that no imbalance occurs. It goes without saying that this protrusion may have a shape that continuously projects in the paper feeding direction between the left and right paper feeding rollers 31 as shown in FIG. Note that the illustrated sheet loading platform 56 has its rear end 56b supported by pins 62 and 63 on the sheet storage frame 55, and as the number of sheets on the loading platform decreases, the leading edge 58a of the loading platform moves toward the paper feed roller. 31 to more firmly engage the sheet with the paper feed roller. Further, the abutting piece 58 may be located on the downstream side of the paper feed roller 31 and may be provided over the entire length in the sheet width direction, but the storage frame 55 at the position 1' facing the paper feed roller 31 is located downstream of the paper feed roller 31. A bent piece 55c of one side plate is fitted into a slit 55b at the bottom of the storage frame so that one side plate 55a can be moved in the width direction so that sheets of different sizes can be accommodated in horizontal or vertical positions or sheets of different sizes.

[Example on the left]

The drive device (drive motor M) of the printing device main body A is driven by its control port. For example, when a printing instruction is given by key operation, if the drive device M is rotated clockwise in FIG. Paper feed roll 8, paper discharge roller 25. The paper feed rollers 31 rotate clockwise at the same timing. At this time, the paper feed roll 8 and the paper ejection roller 25 are operated when a manual sheet (a sheet manually set by the user from the finger slit 26 regardless of the feeding device) remains in the paper path 7 and the paper ejection path 29. This is ejected to the paper ejection stacker. At the same time, the rotation of the paper feed roller

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the sheet feeding device of the present invention, FIG. 2 is a top view, FIG. 3 is an enlarged sectional view, FIG. 4 is a top view of the cassette body 22A, and FIG. 5 is a sheet feeding device. FIG. 6 is an enlarged view of the platform, FIG. 6 is a plan view thereof, and FIG. m7 is a schematic diagram of the drive system. 21...Device machine frame 30...Paper feed rotating body 22
...Cassette body patent Applicant: Japan Seimitsu Kogyo Co., Ltd. Patent
Applicant Alps Electric Co., Ltd. Patent Application No. 206585 filed in 1985 2 Name of the invention Sheet feeding device 3 Relationship to the case of the person making the amendment Patent applicant Address (residence) 111 3167 Miyamachi, Kofu City, Nashi Prefecture Name ( Name) Japan Seimitsu Kogyo Co., Ltd. Address (Residence) 1-7 Yukitani Otsuka-cho, Ota-ku, Tokyo Name: Alps Electric Co., Ltd. 4 Agent address: 400 Contents of amendment 1. Engraving of the specification originally attached to the application.・As per the attached sheet (
(no change in content). 2. As shown in the engraving of the drawing originally attached to the @ document (no changes to the content). 3. Submit a power of attorney for Alps Electric Co., Ltd.

Claims (1)

[Scope of Claims] 1. A paper feed roller connected to an appropriate driving means, a vertically movable sheet loading table that pushes up and presses stacked sheets onto the paper feeding roller, and a leading edge of the sheet on the sheet loading roller. A sheet feeding device comprising a distal end abutting piece that engages with the paper feeding roller to form a feeding gap for one sheet, and separates and feeds sheets one by one from this feeding gap,
The paper feed rollers are arranged at two or more locations on the left and right separated by a distance in the paper feed width direction, and the tip edge of the sheet platform made of a plate-shaped body is shaped so that it comes into contact with the outer periphery of the paper feed roller at the highest position. In addition, a sheet feeding device characterized in that a leading end edge of the sheet mounting table facing each peripheral edge of at least two left and right paper feeding rollers is configured in a protrusion shape protruding in the paper feeding direction. 2. The sheet feeding device according to claim 1, wherein the sheet mounting table is configured to be swingable such that the rear end portion of the plate-shaped body in the sheet feeding direction is supported on a shaft so that the leading end portion in the sheet feeding direction moves up and down. 3. The sheet feeding device according to claim 1, wherein the protrusion of the sheet mounting table is formed at a position facing an inner peripheral edge near the center of the left and right opposing sheet feeding rollers. 4. The sheet feeding device according to claim 1, wherein the protrusion has a shape that approaches the paper feeding roller side.