JPH08133525A - Sheet feeding device and image forming device - Google Patents

Abstract

PURPOSE: To detect a position of a sheet tray in stages more than the number of detecting switches by using a cam-follower swinging according to a moving distance of the sheet tray, and respectively actuating plural detecting switches according to a position of the sheet tray. CONSTITUTION: A cam-follower 26 swinging with a support shaft 26a as the center is arranged on a side surface of a housing magazine 15, and is slidingly contacted with a cam 27 arranged on a side surface of a tray 14, and is swung according to a raising-lowering quantity of the tray 14. In the cam-follower 26, two arm members 26b and 26c are arranged on the free end side, and cams having respectively different shapes are formed on these. In a frame 17, a switch unit 29 provided with two tact switches SW1 and SW2 to detect these, is arranged on a swinging locus of the two arm members 26b and 26c. Four kinds of combinations are set by the two tact switches SW1 and SW2 and the cam- follower 26 provided with the two arm members 26b and 26c, and a sheet residual quantity in four stages is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus capable of feeding sheets such as originals and recording sheets to image forming apparatuses such as printers, copying machines and facsimiles.

[0002]

2. Description of the Related Art Conventionally, a sheet feeding device used in an image forming apparatus such as a printer or a copying machine is configured to feed a large number of sheets such as originals and recording sheets stacked in a sheet storage portion one by one by a feeding roller or the like. It is configured to automatically feed sequentially to the next process.

In the above-mentioned conventional sheet feeding apparatus, in order to confirm the remaining amount of the accommodated sheets, the tray or cassette on which the sheets are stacked is pulled out from the apparatus main body and the amount of the sheets is directly checked. Alternatively, the remaining amount detecting device provided in the sheet feeding device is used for confirmation.

As the remaining amount detecting device, a slit or the like is provided in a sheet accommodating portion such as a tray or a cassette to visually check the remaining amount of the sheet, or a lever moves according to the remaining amount of the sheet. There is a mechanism for displaying the remaining amount of sheets at the position of the lever.

Further, as another remaining amount detecting device, it is provided in a sheet supplying device having a sheet accommodating portion such as a deck capable of accommodating a large number of sheets, and is a sheet stacking plate for accumulating and holding the sheets. A plurality of detection switches are provided along the moving path, the position of the sheet stacking plate that moves according to the change in the sheet stacking amount is detected by the detection switch, and the remaining amount of sheets is displayed based on this detection signal. There is something like this.

[0006]

However, in the case where the above-mentioned detection switch is provided, for example, when detecting the remaining amount of the sheet at four stages of 100%, 75%, 50%, and 25% of the total, there are four positions. It is necessary to install a detection switch in
That is, since the same number of detection switches as the number of detection steps are required, the number of detection switches must be increased if the number of detection steps is increased, which causes a problem of high cost.

Further, when an image forming apparatus such as a printer or a copying machine equipped with the sheet feeding device is remotely operated by a host computer in a network environment or the like, the remaining amount of sheets in the sheet feeding device is controlled from the host computer side. Therefore, in order to confirm the remaining amount of the sheet, the user moves to a position near the device (in the above-mentioned conventional example, a position where the display portion of the device main body can be seen, or a position where the sheet accommodation portion can be pulled out and directly viewed). This is inconvenient for the user.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a sheet feeding apparatus capable of detecting the remaining amount of a sheet with an inexpensive and simple structure and notifying a remote user of the remaining amount of the sheet. is there.

[0009]

The structure of the present invention for achieving the above-mentioned object is a sheet stacking means that moves in accordance with the stacking amount of sheets, and the remaining sheet by detecting the position of the sheet stacking means. In a sheet feeding device provided with a sheet remaining amount detecting unit for detecting the amount, the sheet remaining amount detecting unit is a swinging unit swinging according to a moving amount of the sheet stacking unit, and a swinging amount of the swinging unit. A plurality of detecting means that operate in accordance with the above, and is configured to detect the position of the sheet stacking means by a combination of detection / non-detection of the plurality of detecting means that operates according to the swing amount of the swinging means. It is characterized by having done.

Further, the swinging means has a plurality of arm members, and the detecting means has a plurality of detecting switches which operate corresponding to the respective arm members, and depending on the swinging amount of the swinging means. Each arm member is detected by each detection switch, and the combination of detection / non-detection of the detection switches detects more positions of the sheet stacking means than the number of detection switches. The moving means has two arm members, the detecting means has two detecting switches that operate for each of the arm members, and each arm is operated by each detecting switch in accordance with the swing amount of the swinging means. Each is detected, and four stages of detection are performed by a combination of detection / non-detection of the detection means.

Further, the sheet feeding device has a sheet accommodating means that can be attached to and detached from the apparatus main body, and positioning of the swinging means arranged in the sheet accommodating means and the detecting means arranged in the apparatus main body side. It is characterized by having means.

Further, the sheet feeding device is characterized in that it transmits a signal detected as the remaining amount of the sheet to the host computer to display the remaining amount of the sheet on the host computer.

Further, an image forming apparatus for forming an image on a sheet in accordance with image information is characterized by including the sheet feeding apparatus configured as described above, and further, a signal detected as the remaining amount of the sheet is transmitted. It is characterized in that it is transmitted to the host computer and the remaining amount of sheets is displayed on the host computer.

[0014]

In the above structure, the swinging means swinging according to the amount of movement of the sheet stacking means actuates the plurality of detecting means in accordance with the position of the sheet stacking means, and the plurality of detecting means. Since the position of the sheet stacking means is detected by a combination of detection / non-detection of the sheet stacking means, the position of the sheet stacking means can be detected in more stages than the number of the detecting means. The swinging means provided with the arm member is detected by two detection switches that operate according to the amount of swinging, and position detection is performed by a combination of detection / non-detection of the detection switches. 4 which is the number of detection signal combinations
It is possible to detect at multiple locations, and it is possible to detect twice the number of detection switches.

Further, in the above configuration, the signal detected as the remaining sheet amount is transmitted to the host computer of the remote user and the remaining sheet amount is displayed on the host computer. Sheet feeding device,
Alternatively, even when an image forming apparatus such as a printer having the above sheet feeding apparatus is remotely operated from a host computer,
The user can easily check the remaining amount of the sheet and can provide a convenient device.

[0016]

【Example】

[First Embodiment] An embodiment of the sheet feeding apparatus to which the present invention is applied will be specifically described below with reference to the drawings.
The present embodiment exemplifies a laser beam printer as an image forming apparatus equipped with a deck as a sheet feeding apparatus to which the present invention is applied as an option. 1 is a perspective view of an essential part of a deck according to a first embodiment of the present invention, FIG. 2 is a sectional view of an essential part of the deck, and FIG. 3 is a schematic top view showing a state of a remaining sheet amount detecting means in the deck. 4 is a perspective view of the deck, and FIG. 5 is a schematic cross-sectional view showing the overall configuration of a printer equipped with the deck.

First, a schematic structure of a laser beam printer and a deck will be described with reference to FIG. 1
Is a laser beam printer (hereinafter abbreviated as "LBP") as an image forming apparatus, and has the following functions. Reference numeral 2 denotes a cassette in which sheets S are stacked and housed, and is mounted detachably on the lower side of the apparatus in two steps, upper and lower. A pickup roller 3 feeds the sheets S stacked in the cassette 2 from the uppermost side. A retard roller pair 4 separates and conveys the fed sheets S one by one. A pair of feed rollers 5 conveys the separated sheet S. Reference numeral 6 denotes a registration roller pair, which abuts the leading edge of the sheet S on the nip portion to correct the skew and then conveys the sheet S to the image forming unit at a predetermined timing.

Reference numeral 7 denotes a process cartridge containing a known process means for image formation, which is detachably mounted on the main body of the apparatus. In the process cartridge 7, a photosensitive drum 7a as an image carrier, a charger 7b for charging the surface of the drum 7a, and the drum 7 are provided.
a developing device 7c for forming a developed image (toner image) on a,
A cleaning device 7d for removing waste toner and the like remaining on the surface of the drum 7a is built in, and laser light is irradiated from the laser exposure device 8 to the photoconductor drum 7a in accordance with image information for writing. Is performed. The transfer roller 9 is pressed against the photosensitive drum 7a, and when passing between the photosensitive drum 7a and the transfer roller 9, a voltage having a polarity opposite to that of the toner image is applied to the surface of the drum 7a. The toner image is transferred to the sheet S. A fixing device 10 fixes the transferred image by applying heat and pressure to the sheet S after the image transfer. Then, the sheet S after the image fixing is conveyed through the reversing path, and is discharged by the discharge roller pair 11 to the discharge tray 12 formed on the upper surface of the apparatus with the image side facing down (face down).

Next, the sheet feeding device will be described.
The deck 13 serving as a sheet feeding device also serves as a mounting table for the LBP1 and is arranged below the LBP1.
The sheet supply device 13 stacks and stores relatively large-sized sheets S that cannot be stored in the cassette 2, and can supply a large amount of the sheets S to the LBP 1.

Reference numeral 14 denotes a tray on which the sheets S can be stacked and which can be moved up and down. The tray 14 is equipped in a storage box 15 that can be pulled out to stack the sheets S on the tray 14. The storage box 15 is configured such that guide rails 16 provided on the left and right sides are supported by rail-shaped guides 18 provided on the left and right sides in a frame 17 so as to be drawn out to the front side of the apparatus along the guides 18. ing. The frame 17 has a pickup roller 19 for feeding the sheet S on the tray 14 from the uppermost side,
A retard roller pair 20 that separates and conveys the delivered sheets S one by one, and a conveyance unit 21 that conveys the separated sheets S to the LBP 1 are provided.

The tray 14 has a wire rope 22.
a, 22b, 22c, 22d are fixed near the four corners and the storage 15
It is suspended inside. The other ends of the wire ropes are pulleys 23a, 23 rotatably provided on the upper part of the storage box 15.
Via b, 23c and 23d, it is connected to a take-up winch 24 provided at the front and rear of the lower part of the storage case 15.

The take-up winch 24 is fixed to a take-up shaft 25 to which a gear (not shown) is attached, and a motor M provided on the frame 17 with the storage case 15 mounted on the frame 17. Connected to a gear (not shown). Then, the winding winch 24 is rotated by driving the motor M, each wire rope is wound around the body of the winding winch 24, and the tray 14 is raised. Further, by pulling out the storage 15 from the frame 17, the connection between the gear of the take-up winch 24 and the gear of the motor M fixed to the frame 17 is released, and the take-up winch 24 due to the weight of the sheet S and the tray 14. Each of the wire ropes wound around is unwound and the tray 14 descends. A brake damper (not shown) is provided on the inner side of the winding shaft 25 in order to reduce the impact received when the tray 14 descends.
It is connected to the gear attached to.

Further, the frame 17 is provided with a detection means (not shown) for detecting the upper surface (paper surface) of the tray 14 which has risen, and when the upper surface (paper surface) of the tray 14 which has been raised is detected, a winding winch. The drive of the motor M rotating the 24 is stopped. Further, when the sheet S on the tray 14 is sent out by the pickup roller 19 and the retard roller pair 20 installed on the frame 17, and the paper surface becomes low, the motor M is driven again until the detecting means detects the paper surface, and the tray 14 is moved. Raise. This allows tray 14
It is possible to always hold the uppermost surface of the sheets S stacked on it at a substantially constant position.

A sheet remaining amount detecting means for detecting the remaining amount (laden amount) of the sheets S stacked on the tray 14 will be described with reference to FIGS. 1 to 4.

As shown in the drawing, a cam follower 26 swinging around a support shaft 26a provided at the lower end is provided on the side surface of the storage box 15, and is provided on the side surface of the tray 14. It is slidably in contact with the cam 27 and swings in accordance with the amount of elevation of the tray 14. The cam follower 26 is provided with two arm members 26b and 26c on the free end side, and the arm members 26b and 26c are formed with cams having different shapes. In the present embodiment, the cam follower described above is used.
Although the upper end side of the reference numeral 26 swings about the support shaft 26a on the lower end side, the present invention is not limited to this, and the swing center of the cam follower may be provided anywhere, for example, centering on the upper end side. You may comprise so that a lower end side may be rocked.

Further, the cam follower 26 is biased by a spring 28 in a direction of sliding contact with the cam 27, and is stopped at a predetermined position shown in FIG. 1 by a stopper (not shown). Note that the cam follower 26 may be configured to slide on the cam 27 by its own weight without using the spring 28. In this case, the number of parts can be reduced and the cost can be reduced.

In the frame 17, two tactile switches SW for detecting the arm members 26b and 26c are located on the swing loci of the two arm members 26b and 26c.
A switch unit 29 including 1 and SW2 is provided. In this switch unit 29, tact switches SW1 and SW2 are arranged in a holder 30, and the tact switch SW
1, leaf springs 31 and 32 are arranged in front of SW2. As shown in FIG. 2, the switch unit 29 is slidably provided on the side plate 17a of the frame 17 with the tact switches SW1 and SW2 facing the storage box 15 side. A plurality of ribs 30a are provided on the outer wall of the holder 30 so that the sliding resistance of the switch unit 29 is reduced. Also, by unitizing the plurality of switches, wiring and the like can be easily performed, and the assembling property can be improved.

The switch unit 29 has a leaf spring 33.
Is urged in the direction of projecting to the storage box 15 side, and a not-shown positioning projection is provided on the projecting side, and the projection contacts the side plate 15a of the storage box 15 and the switch unit 29. Is positioned.
As a result, even if the storage box 15 is adjusted in the pull-out direction (positioning of front and rear, etc.), the tact switch SW1,
The interval between SW2 and the side plate 15a of the storage case 15 is always kept constant, and the tact switch S by the arm members 26b and 26c.
ON / OFF of W1 and SW2 is surely performed, and detection failure can be prevented. Also, when the storage 15 is pulled out, the switch unit 29 is stopped at a fixed position by a stopper (not shown).

As described above, the cam follower 26 is integrally provided with the two arm members 26b and 26c, and the cams having different shapes are formed on the tip ends thereof. According to the swing amount of the cam follower 26, the arm members 26b,
26c turns on / off tact switches SW1 and SW2 respectively
It is arranged so as to F. The cam follower 26 is formed with a curved surface in sliding contact with the cam 27 so that the cam follower 26 swings substantially in proportion to the amount of movement (elevation amount) of the tray 14 (see FIG. 1). In addition, the tact switches SW1 and SW2
Are turned on by the cams formed on the arm members 26b and 26c of the cam follower 26 pressing the leaf springs 31 and 32 of the switch unit 29. A photo sensor may be used instead of the tact switch, and in this case, the shape of the arm member needs to be a flag shape that allows the photo sensor to shield and transmit light. With this configuration, it is possible to further improve the detection accuracy.

The cam shapes of the two arm members 26b and 26c provided on the cam follower 26 and the sheet remaining amount detecting operation will be described with reference to FIG.

The cam shape of one arm 26b is formed such that the central portion thereof projects toward the leaf spring 31 side. This arm 26b is used for the tray 14 when the stacking capacity of the sheets S is 100%.
3A, the cam does not contact the leaf spring 31 and the tact switch SW1 is in the OFF state as shown in FIG. The cam follower 26 swings as the stacking amount of the sheets S decreases, and the arm 26b moves in the direction of the arrow in the figure. Therefore, the loading capacity of the sheets S is 75% and 50%.
At the position of the tray 14 at the time of%, the cam contacts the leaf spring 31 as shown in FIGS.
Turn on W1. Furthermore, the loading capacity of the sheets S is reduced,
At the position of the tray 14 when the stacking amount of the sheets S is 25% or less, the cam does not contact the leaf spring 31 and the tact switch SW1 is turned off again as shown in FIG. 3D.

The cam shape of the other arm 26c is formed such that the rear portion in the moving direction projects toward the leaf spring 32 side. Similar to the arm 26b, the arm 26c also moves in the direction of the arrow in the drawing as the stacking amount of the sheets S decreases, and at the position of the tray 14 when the stacking amounts of the sheets S are 100% and 75%. As shown in FIGS. 3A and 3B, the cam is not in contact with the leaf spring 32, and the tact switch is in the OFF state. Then, at the position of the tray 14 when the stacking amount of the sheets S is 50% and 25%, the cam contacts the leaf spring 32 and turns on the tact switch as shown in FIGS. 3 (c) and 3 (d). .

Therefore, the tact switches SW1 and SW
2 is an arm member that moves according to the position of the tray 14
ON / OFF depending on 26b and 26c as shown in Table 1 below.
To be done.

[0034]

[Table 1]

In this way, two tact switches SW
1, SW2 and the cam follower 26 having the two arm members 26b and 26c can set four kinds of combinations as shown in Table 1 above, and a four-stage seat can be set based on a signal generated for each combination. The remaining amount can be detected. When there are no more sheets, the sheet presence / absence detecting means (not shown) detects the sheets.

Further, as shown in FIG. 1, the LBP 1 equipped with the deck 13 is connected to a host computer H, and a signal for detecting the remaining amount of the sheet S is sent to the host computer H, The remaining sheet amount is displayed on the display of the host computer H, and the user can easily confirm the remaining sheet amount.

[Second Embodiment] Next, a second embodiment of the sheet feeding apparatus will be described with reference to FIG. FIG. 6 is an enlarged view of a main part of a deck as a sheet feeding device according to the second embodiment of the present invention. Since the schematic structure of the deck is the same as that of the first embodiment described above, the same members are designated by the same reference numerals and the description thereof is incorporated herein by reference.

In this embodiment, as compared with the first embodiment described above, as shown in FIG. 6, the swinging direction of the cam follower 26 constituting the sheet remaining amount detecting means is the same as the attaching / detaching direction of the storage 15 (see FIG. The switch unit 29 is configured such that the sliding direction of the holder 30 is orthogonal to the swing direction of the cam follower 20. The switch unit 29 is operated by the arm members 26b and 26c of the Guycam follower 26. It is provided by rotating 90 degrees so that. With such a configuration, the area occupied by the side plate 15a of the storage case 15 by the cam follower 26 can be made smaller than that of the configuration of the first embodiment described above.

[Third Embodiment] Next, a third embodiment of the sheet feeding apparatus will be described with reference to the drawings. In the present embodiment, a configuration in which the present invention is applied to the sheet cassette of the printer of the first embodiment described above as a sheet supply device will be described as an example. FIG. 7 is a schematic sectional view of a sheet cassette as a sheet feeding device according to the third embodiment of the present invention.
Since the schematic configuration of the printer is the same as that of the first embodiment described above, detailed description thereof will be omitted here.

As shown in FIG. 7, an intermediate plate 35 is provided inside the sheet cassette 2 so as to be swingable about a fulcrum 34, and the intermediate plate 35 is placed from below to above by a coil spring 36. It is biased toward the pick-up roller side shown. A cam 37 is attached to the tip (right end in the figure) of the middle plate 35. Further, the supporting shaft is made to face the cam 37.
A cam follower 38 that swings around 38a is provided, and the cam follower 38 is biased by a spring 39 in a direction of sliding contact with the cam 37. Two arm members 38b and 38c are integrally provided at the tip end on the swing side of the cam follower 38. The arm members 38b and 38c project to the outside of the cassette, and the switch unit 40 arranged on the apparatus main body side. The tact switches SW1 and SW2 of O through the leaf springs 41 and 42.
It is designed to be turned off / on.

The cam shapes of the arm members 38b and 38c provided on the cam follower 38 in the figure are formed in the same manner as the cam shape of the arm member of the first embodiment described above, and one arm member 38b is a seat. When the loading amount of S is 75% and 50%, the cam comes into contact with the leaf spring 41 at the position of the intermediate plate 35 to turn on the tact switch SW1, and when the loading amount of the sheet S is 100% and 25%. At the position of the plate 35, the cam does not contact the plate spring 41 and the tact switch SW1 is turned off. In the other arm member 38c, the cam contacts the leaf spring 42 at the position of the intermediate plate 35 when the loading amount of the sheets S is 100% and 75%, and the tact switch SW2 is turned on. 50% and
At the position of the intermediate plate 35 at the time of 25%, the cam does not contact the plate spring 42 and the tact switch SW2 is turned off.

In this way, when the present invention is applied to the sheet cassette of the printer, as shown in FIG.
Cam at a position as far as possible from the swing center (fulcrum 34) of
It is preferable to attach 37, and the swing range of the cam 37 can be set to a large range, so that the detection accuracy of the remaining amount of sheets can be improved.

As described above, in the embodiment of the present invention, the cam follower having the two arm members and the two switches SW1 and SW2 which are individually operated by the arm members have four stages of seat remaining larger than the number of the switches. Since the quantity can be detected, the number of parts can be reduced, the assemblability can be improved, and the cost can be reduced.

In the above-described embodiment, the cam follower as the swinging means is provided with two arm members, and two detection switches individually operated by the arm members are provided. The invention is not limited to this, and the arm member and the detection switch may be provided in two or more sets, for example, three sets may be provided.
With this configuration, it is possible to detect the remaining amount of the sheet in eight steps.

[0045]

As described above, the cam follower swinging according to the movement amount of the sheet tray actuates the plurality of detection switches according to the position of the tray, and turns on / off the plurality of detection switches. The position of the sheet tray, that is, the remaining amount of the sheet is detected by a combination of the above, so that the position of the sheet tray can be detected in more stages than the number of detection switches. The number of combinations of detection signals of each detection switch is detected by detecting the cam follower equipped with the two detection switches that operate according to the amount of swing, and detecting the position by the combination of ON / OFF of the detection switches. It is possible to detect four places, which is twice the number of detection switches. As a result, the number of detection switches can be made smaller than in the conventional case, the number of parts can be reduced, the cost can be reduced, and the assembling property can be further improved.

Further, even when an image forming apparatus such as a printer having the above-mentioned sheet feeding apparatus is remotely operated from the host computer, the signal detected as the remaining amount of sheets is transmitted to the remote user's host computer and the host computer is operated. By displaying the sheet remaining amount on the upper side, the user can easily confirm the sheet remaining amount, and it is possible to provide a user-friendly device.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a deck according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an essential part of the deck.

FIG. 3 is a schematic top view showing a state of remaining sheet amount detecting means in the deck.

FIG. 4 is a perspective view of the deck.

FIG. 5 is a schematic cross-sectional view showing the overall configuration of a printer equipped with the deck.

FIG. 6 is an enlarged view of an essential part showing a remaining sheet amount detecting means of a deck according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view of essential parts of a sheet cassette according to a third embodiment of the present invention.

[Explanation of symbols]

1 ... Laser beam printer (LBP) 2 ... Sheet cassette 3 ... Pickup roller 4 ... Retard roller pair 5 ... Feed roller pair 6 ... Registration roller pair 7 ... Process cartridge 7a ... Photosensitive drum 7b ... Charger 7c ... Developer 7d ... Cleaning device 8 ... Laser exposure device 9 ... Transfer roller 10 ... Fixing device 11 ... Ejection roller pair 12 ... Ejection tray 13 ... Sheet feeding device (deck) 14 ... Tray 15 ... Storage box 15a ... Side plate 16 ... Guide rail 17 ... Frame 17a … Side plate 18… Guide 19
... Pickup roller 20 ... Retard roller pair 21 ... Conveyor 22a, 22b, 22c, 22d ... Wire rope 23a,
23b, 23c, 23d ... Pulley 24 ... Winding winch 25 ... Winding shaft 26 ... Cam follower 26a ... Spindle 26b, 26c ... Arm 27 ... Cam 28 ... Spring 29 ... Switch unit 30 ...
Holder 30a ... Ribs 31, 32, 33 ... Leaf spring 34 ... Support point
35 ... Middle plate 36 ... Coil spring 37 ... Cam 38 ... Cam follower 39 ... Spring 40 ... Switch unit 41, 42 ... Leaf spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuzo Isoda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yasuhiro Uchida 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Jun Saito 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (7)

[Claims] 1. A sheet feeding apparatus comprising: a sheet stacking unit that moves according to the stacking amount of sheets; and a sheet remaining amount detecting unit that detects the remaining amount of sheets by detecting the position of the sheet stacking unit. The sheet remaining amount detecting means includes a swinging means that swings according to the amount of movement of the sheet stacking means, and a plurality of detecting means that operates according to the swinging amount of the swinging means. A sheet feeding device, characterized in that the position of the sheet stacking means is detected by a combination of detection / non-detection of a plurality of detection means that operate according to the amount of rocking of the means. 2. The swing means has a plurality of arm members, and the detection means has a plurality of detection switches that operate corresponding to the respective arm members, and according to the swing amount of the swing means. Each arm member is detected by each detection switch,
2. The sheet feeding apparatus according to claim 1, wherein the position of the sheet stacking means, which is larger than the number of detection switches, is detected by a combination of detection / non-detection of the detection switches. 3. The swinging means has two arm members, and the detecting means has two detecting switches which are activated for each of the arm members, and which corresponds to the swinging amount of the swinging means. The sheet feeding apparatus according to claim 1, wherein each arm is detected by each detection switch, and four stages of detection are performed by a combination of detection / non-detection of the detection means. 4. The sheet feeding device has a sheet accommodating means that can be attached to and detached from the apparatus body, and positioning of the swinging means arranged in the sheet accommodating means and the detecting means arranged on the apparatus body side. The sheet feeding apparatus according to claim 1, further comprising means. 5. The sheet feeding device transmits a signal detected as the remaining amount of sheets to a host computer,
2. The sheet feeding apparatus according to claim 1, wherein the host computer displays the remaining amount of sheets. 6. A sheet supply device according to claim 1, and an image forming unit for forming an image on a sheet supplied by the sheet supply device according to image information. An image forming apparatus characterized by the above. 7. The image forming apparatus according to claim 6, wherein the image forming apparatus transmits a signal detected as the remaining amount of sheets to the host computer to display the remaining amount of sheets on the host computer. Image forming apparatus.