JP2002227877A - Spring clutch, and sheet feeding apparatus and image forming apparatus using spring clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive spring clutch having increased margin of chattering noise at a time of idling, and a sheet feeding apparatus and an image forming apparatus using the spring clutch, thereby to be adaptable for speeding-up of a printer, a copy machine, or the other apparatus. SOLUTION: The spring clutch comprises: a rotatable input gear 101 for receiving driving force; a rotatable output gear 104 for outputting the driving force; a clutch spring 102 wound around an input body 101b formed in the input gear 101 and an output gear body 104c formed in the output gear 104; and a collar member 103 engaged with an end of the clutch spring 102. In this clutch, the engagement and the disengagement to and from the collar member 103 transmit the driving force from the input gear 101 to the output gear 104, to an inner diameter of the clutch spring 102 is tapered from the input gear 101 side toward the output gear 104 side to become gradually small.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring, a printer, a facsimile, a copying machine, or an apparatus having a transmission mechanism, which turns on and off a drive transmission, a sheet conveying apparatus using the same, and an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, a spring clutch has been used as a drive transmission switching mechanism for an input section and an output section in a small device or the like. To explain an example of a conventionally used spring clutch, as shown in FIG. 10, an input gear 301 includes a gear portion 301a that is driven from the outside and an input cylinder 301b around which the upper half of the clutch spring 302 is wound. Have. Also,
The shaft 304b of the output gear 304 is rotatably loosely fitted into the through hole of the input gear 301. Here, the locking projection 304a prevents the input gear 301 and the output gear 304 from coming off in the thrust direction. The lower half of the clutch spring 302 is wound around the output cylinder 304c of the output gear 304, and a three-dimensional bent portion 302 at the lower end of the spring is provided.
c is inserted into the groove 304d of the output gear 304.

A collar member 303 is provided outside the clutch spring 302.
Is provided, and a flat bent portion 3 at the upper end of the clutch spring is provided in the groove 303a.
02a is engaged. In addition, a projection 303
b is provided. The collar member 303 can be stopped by the movable hook member 305 being hooked on the projection 303b. In addition, the hook member 305 is
It is also possible to escape from b. In this case, the collar member 303
Is rotatable. The hook member 305 is, for example, a solenoid armature.

When the clutch spring 302 is free, the inner diameter d of the helix 302b is smaller than the outer diameter Din of the input cylinder 301b. This diameter difference Din-d is called a tightening allowance, and is 0.1 to 0.3 mm.
Often taken between. Clutch spring 302 is input gear 301
When it is assembled into the input cylinder 301b, it is expanded by an amount corresponding to the tightening margin, and a predetermined pressure is applied to the input cylinder 301b. Input cylinder 301b and output cylinder 30
Since the outer diameter of 4c is substantially equal, the clutch spring 302 applies the same pressure to the output cylinder 304c as to the input cylinder 301b.

When transmitting a driving torque given to the input gear 301 from a driving source (not shown) to the output gear 304, the hooking member 305 moves to a position (a two-dot chain line in FIG. 10) which escapes from the projection 303b. At that time, the collar member 303 can freely rotate. When the input gear 301 rotates counterclockwise in FIG. 10B, which is a cross section taken along the line AA in FIG.
Is in contact with the input cylinder 301b with a predetermined pressure, a frictional force is generated, and the clutch spring 302 tries to rotate following the input cylinder 301b. At this time, since the winding direction of the clutch spring 302 is a direction in which the clutch spring 302 tightens against the input cylinder 301b, the pressure of the clutch spring 302 increases, and the frictional force also increases. As described above, the input cylinder 301b and the clutch spring 302 are firmly connected and rotate at the same time. Further, the clutch spring 302 and the output gear 304 are connected to each other by a three-dimensional bending portion 302c by a groove 304d.
Further, since a large frictional force is generated in the output cylinder 304c, the output cylinder 304c rotates at the same time. In this way, the rotation of the input gear 301 is transmitted to the output gear 304.

[0006] When the input gear 301 does not transmit the drive and runs idle, the hook member 305 is hooked on the projection 303b, and the collar member 303 is stopped. Groove 303a of collar member
And the plane bend 302a of the clutch spring are engaged,
The clutch spring 302 is also stopped. Therefore, the input cylinder 301b
Does not cause an increase in frictional force due to rotation,
The input cylinder 301b and the clutch spring 302 slide. Output gear 30
4 is connected to the clutch spring 302, so that the rotation is stopped. Grease is often applied between the input cylinder 301b and the clutch spring 302 in order to smoothly slide.

As described above, the spring clutch 300 can turn on and off the drive transmission with a simple structure, so that an inexpensive device can be formed.

[0008]

However, when the drive of the input gear 301 is not transmitted, that is, when the input gear is idling, the input cylinder 301b and the clutch spring 302 slide with a predetermined frictional force. Depending on the vibration, there was a possibility that a strange sound was generated. In most cases, such noise has been suppressed by the application of grease, but in recent years, especially as printers and copiers have become faster, the number of rotations of the spring clutch has increased, and shocks when stopping the clutch spring have been reduced. As it has increased, the margin for clutch noise has been reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive spring clutch and a sheet using the same, which can increase the margin for noise during idling so as to be able to cope with high-speed printers, copiers and other apparatuses. An object of the present invention is to provide a transport device and an image forming apparatus.

[0010]

A typical configuration according to the present invention for achieving the above object comprises a rotatable input section for inputting a driving force, and a rotatable output section for outputting a driving force. A coil spring wound around and attached to the input cylinder formed in the input section and the output cylinder formed in the output section, and the input cylinder and the output cylinder are connected by tightening the coil spring. In a spring clutch in which the driving force is transmitted and the input cylinder and the output cylinder are disconnected by the loosening of the coil spring and the driving force is not transmitted, the inner diameter of the coil spring is gradually changed to form a tapered shape. It is characterized by having. Further, a rotatable input unit to which a driving force is input, a rotatable output unit to output a driving force, and a winding unit mounted around an input cylinder formed at the input unit and an output cylinder formed at the output unit. A coil spring having a locking member to which one end of the coil spring is locked, and transmitting a driving force from the input unit to the output unit by locking and unlocking the locking member. The inner diameter of the coil spring is tapered such that the inner diameter gradually decreases from the input portion side to the output portion side.

Further, the present invention is characterized in that a sheet conveying device using the spring clutch for switching the driving force transmission and an image forming apparatus having the same are configured.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an image forming apparatus provided with a sheet conveying device using a spring clutch according to an embodiment of the present invention will be described with reference to the drawings.

First Embodiment A laser beam printer will be described as an example of an image forming apparatus using a spring clutch according to a first embodiment.

{Overall Configuration of Image Forming Apparatus} FIG. 1 is a schematic sectional view of a laser beam printer as an image forming apparatus according to the first embodiment. The image forming apparatus 1 can form an image on both sides of a sheet as well as on one side thereof, and includes an image forming unit 2 for forming an image and a sheet re-feeding / conveying unit 3 for re-feeding a sheet. .

When performing double-sided recording, the sheet P is fed to the feeding section 4
After the image is formed by the image forming unit 2, the image is conveyed to the switchback roller 5. When the switchback roller 5 rotates in the reverse direction, the sheet P is continuously sent to the sheet re-feeding / conveying unit 3 in a state where the front end and the rear end are in the reverse direction.

The sheet P conveyed to the sheet re-feeding conveyance unit 3 by the switchback roller is conveyed to the lateral registration correction unit 6. The lateral registration correction unit 6 is disposed at a reference plate 7, an end on the reference plate side, a roller 8 having a center axis substantially perpendicular to the reference plate 7, a roller 8 opposed to the roller 8, and a center with respect to the roller axis. It is constituted by a skew feeding roller 9 whose axis is inclined several degrees.

The sheet P may skew while passing through the image forming unit 2 or may enter the sheet re-feeding / conveying unit 3 in a state where the sheet P is shifted in the sheet width direction. The lateral registration correction unit has the purpose of correcting the sheet posture to the correct position again along the reference plate 7 before forming the image on the second side.

The transport detecting means 10 comprises an arm member 11 and a photosensor 12 which are rotatably held in the transport direction from above the re-feed transport section. Arm member 11
When the sheet passes, the sheet is rotated by the leading end of the sheet, and the flag portion of the arm member crosses the photosensor 12. This makes it possible to determine whether the sheet has passed. The sheet P corrected for the lateral registration is fed into the refeed reversing guide 13 curved upward.
Is sent again to the image forming section 2 along the line. here,
An image on the second side is formed on the sheet, and thereafter, the sheet is sent to the sheet discharge unit 14 and stacked on the sheet discharge table 15.

At the time of continuous double-sided printing, the first sheet P1 fed from the feeding section 4 to the first feeding path and the sheet P1 fed from the refeeding feeding section 3, which is the second feeding path, to the image forming section 2. In this embodiment, in order to prevent the second sheet P2 from colliding at the confluence of the conveyance path, the sheet P2 is stopped by the re-feeding conveyance section 3 and is conveyed to the image forming section after the sheet P1 has passed. Is controlled. Control necessary for double-sided conveyance and the like is performed by the controller board 16.

{Driving Transmission to Roller 8} Next, a configuration for transmitting driving to the roller 8 of the sheet re-feeding / transporting section 3 will be described. As shown in the cut-out portion in FIG. 1, the drive transmission portion of the roller 8 is located on the back side of the apparatus.

The drive is transmitted to the spring clutch 100 through gears 17 and 18 by a motor (not shown). Gear 17, 1
8, the spring clutch 100 is the shaft 20 caulked to the stay 19
(See FIG. 2) so as to be rotatable. Here, the stay 19 is the gears 17 and 18 and the spring clutch 100 in FIG.
, The shaft 20 extends from the front to the back.

FIG. 2 is an explanatory view of the stay 19, the spring clutch 200 and the like as viewed from the left side of FIG. The stay 19 holds a solenoid 21, and a solenoid armature 22 (see FIG. 1) as a hook portion can be hooked on a projection of the spring clutch 100. Spring clutch
100 output gear 104 meshes with roller drive gear 23. In the present embodiment, a roller having a small diameter is rotated at a high speed in order to increase the speed and reduce the size of the apparatus. Therefore, the rotation speed of the spring clutch 100 is about 300 rpm, which is 5 to 10 times faster than the conventional one.

{Spring Clutch} Next, the spring clutch 100 will be described with reference to FIGS. 3 is a main cross-sectional view of the spring clutch, FIG. 4 shows the spring clutch, FIG. 3A is an exploded view, and FIG. 3B is an explanatory view of FIG.

The spring clutch 100 according to this embodiment includes an input gear 101 as an input unit, an output gear 104 as an output unit,
It is the same as the conventional example in that the clutch spring 102 is formed by a coil spring and the collar member 103 is a locking member. That is, the input gear 101 has a gear portion 101a that is driven from the outside and an input body 101b around which the upper half of the clutch spring 102 is wound. Output gear 104 is input gear 10
The shaft 104b is gently rotatably fitted in the one through hole, and the locking projection 104a prevents the input gear 101 and the output gear 104 from coming off in the thrust direction. The lower half of the clutch spring 102 is wound around the output cylinder 104c of the output gear 104. The flat bent portion 102a at the upper end of the spring is
3b, and the three-dimensional bent portion 102c at the lower end of the spring is
4 is inserted into the groove 104d.

Since the sheet P2 must be conveyed to at least the conveyance detecting means 10 at the time of double-sided printing, the controller board 16 sends a signal to the solenoid 21 and pulls the solenoid armature 22 by sucking the solenoid 21. 1 is moved to the position indicated by the two-dot chain line. As a result, the input gear 101 and the output gear 104 of the spring clutch 100 are connected, and the spring clutch 100 itself rotates about the shaft 20 to transmit the drive from the output gear 104 to the roller gear 23. Therefore, the roller 8 directly connected to the roller gear 23 rotates, and the sheet P2 is conveyed.

When the sheet P2 is detected by the conveyance detecting means 10, the controller board 16 next determines whether or not the sheet P2 is to be put on standby. In the case of waiting, the position of the solenoid armature 22 which has been at the position of the two-dot chain line in FIG. 1 is moved to the position of the solid line, and the protrusion 103b provided on the collar member 103 of the spring clutch 100 is hooked on the solenoid armature 22. . As a result, the spring clutch 100 idles, and the sheet P2 stops and stands by. In this embodiment, a plurality of projections 103b are provided on the outer periphery of the collar member 103 in order to accurately define the standby position of the sheet P2.

(Shape of Clutch Spring) The spring clutch 100 according to the present embodiment is characterized in that when the clutch spring 102 is free, the inner diameter of the helical portion 102b has a tapered shape widened toward the input gear 101 side. It is a target. That is,
The clutch spring diameter d1 on the input gear side, the clutch spring diameter d2 on the output gear side, and the outer diameter Din of the input cylinder of the helix 102b.
Is Din>d1> d2, and the difference between d1 and d2 is 0.05
mm. Note that the input cylinder has a straight shape with an outer diameter Din.

Also in this embodiment, the tightening allowance is 0.1 mm.
It should be within 0.3mm. When the clutch spring 102 is incorporated in the input gear 101, it is expanded by the amount of the tightening allowance. In this case, the pressure applied by the clutch spring 102 to the input cylinder 101b gradually increases from the input side to the output side.

(Mechanism of sound change) Here, the mechanism of sound change that may occur from the conventional spring clutch and the effect of the present embodiment will be described with reference to FIG.

The transition from the state in which the output gear 104 is drivingly connected and rotated to the idling state occurs because the collar member 103 is suddenly stopped by the solenoid armature 22. When the collar member 103 stops, the flat bent portion 102a of the clutch spring also stops at the same time, so that the clutch spring 102 that has been wound with a large force on the input cylinder 101b is loosened, and the input cylinder 101b and the clutch spring 102 slide. Begin to. At this time, at one point of the clutch spring 102, the co-rotating force (frictional force) of the input gear 101 and the return force of the spring should balance. However, if this balance is lost, the spring will vibrate, causing a so-called stick-slip. The sound generated at the time of this stick slip is the sound of the spring clutch.

The largest disturbance factor that causes a loss of balance is when the clutch spring 102 starts to idle. At this time, the flat bent portion 102a of the clutch spring 102
Is suddenly stopped by the groove 103a of the collar member 103, so that the impact is easily transmitted to the spring. This impact becomes disturbance and causes stick-slip. For example, when the spring clutch 100 is rotating at a high speed, or when the spring pressure is high and the tightening force is large, it is considered that the energy of this impact increases.

On the other hand, in the present embodiment, the clutch spring 102 is a tapered spring as described above, so that the pressure in the vicinity of the flat bent portion 102a to which the impact is easily transmitted is reduced, and the impact energy causing stick-slip is reduced. Can be reduced.

Further, in the present embodiment, the pressure applied to the input cylinder 101b of the clutch spring 102 gradually changes, and the entraining force (frictional force) gradually changes. Also,
The spring return force also changes gradually because the tightening margin is changing. As a result, the frequency of each point of the spring at the time of stick-slip changes, and resonance hardly occurs.

Regarding the effect of the present embodiment, a demonstration experiment was conducted without applying grease between the clutch spring 102 and the input cylinder 101b so that stick-slip is likely to occur. When the clutch spring was formed into a tapered shape as in the present embodiment, the rate of occurrence of noise was reduced to about 1/3.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 6 shows a spring clutch according to the second embodiment, in which (a) is an exploded view and (b) is (a).
FIG. This embodiment is the same as the first embodiment except for the spring clutch.

In this embodiment, the input cylinder 101b has an inverted taper as shown in the figure instead of using a conventional straight spring as the clutch spring 102. That is, the input cylinder 101
The outer diameter of b is configured to gradually increase from the input side to the output side. Here, assuming that the smaller dimension of the input cylinder is Din1 and the larger dimension is Din2, the relationship with the inner diameter d of the clutch spring 102 is Din2>Din1> d. The difference between Din2 and Din1 is about 0.03 mm to 0.1 mm. Note that the clutch spring 102 has a straight shape with an inner diameter d.

The effect of this embodiment is the same as that of the first embodiment. In the demonstration test, the rate of sound generation was 1/2.

The input gear 101 of the second embodiment has
It goes without saying that the clutch spring 102 of the first embodiment may be used in combination. In this case, Din2> Din1
>D1> d2. In the demonstration experiment, the effect was the most effective, and the distorted sound was 0%.

[Third Embodiment] Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a schematic cross-sectional explanatory view of a laser printer 51 of another type different from the first embodiment. The laser printer 51 mainly includes a sheet stacking table 52, a feeding roller 53, an image forming unit 54, and a discharging unit 55.

The sheet P on the loading table 52 is fed by a feed roller 53 and is conveyed to the image forming unit 54. The sheet P is discharged to a discharge unit 55 after an image is formed by the image forming unit 54. At this time, the feeding roller 53 makes only one rotation per sheet, and the coaxial roller 56 then follows only with the sheet. For one rotation control of the feed roller 53,
In the present embodiment, a spring clutch 200 is used.

FIG. 8 is an exploded perspective view of a feeding section including the feeding roller 53, FIG. 9 shows a spring clutch of the present embodiment, (a) is a sectional view, and (b) is a description of a clutch spring. FIG.
The shaft 67 supporting the feeding roller 53 and the roller 56 is provided with a feeding frame.
57 is rotatably held by cams 58 and 59.
The cams 58 and 59 rotate integrally with the shaft 67, and also have a bearing function of sliding with respect to the feeding frame 57.

The cam 58 is provided with a groove 204 of the spring clutch 200.
e is fixed. The feeding frame 57 includes a feeding roller 53
, A separation plate urging means 61, a middle plate 64 for pressing the sheet P against the feed roller 53, a spring clutch
It holds a solenoid 66 which is a hooking means of 200. The arms 62 and 63 fixed to the middle plate 64 are pressed against the cams 58 and 59 by the urging means 65. Here, since the cams 58 and 59 rotating integrally with the shaft 67 push up the arms 62 and 63, the intermediate plate 64 also swings. Sheets P are stacked between the middle plate 64 and the feeding roller 53.

When the stacking sheet P is fed, the solenoid armature 66a, which has been caught on the projection 203b of the spring clutch 200, is pulled, and the spring clutch 200 is connected to the input gear 201 and the output section 204 and drives the shaft 67. Tell As the shaft 67 rotates, the pushed-down intermediate plate 64 swings, pressing the stacked sheets P against the feed roller side, and at the same time, the feed roller 53 rotates. At this time, the stacked sheets are separated by the separation pad 60 one by one, and the uppermost sheet of the stacked sheets P is fed.

Here, the spring clutch 200 according to the present embodiment will be described with reference to FIG. The input gear 201 and the collar member 203 of the present embodiment are the same as those of the conventional example and the first embodiment. That is, the input gear 201 has a gear portion 201a that is driven from the outside and an input cylinder 201b around which the upper half of the clutch spring 202 is wound.

However, in this embodiment, unlike the first embodiment, an output section 204 for rotating the cam 58 (see FIG. 8) is provided on the output side instead of a gear. Then, the output unit 204 operates in conjunction with the cam 58 to rotate the shaft 67 and the feed roller 5.
Rotate 3.

The output portion 204 is loosely fitted into the through hole of the input gear 201 so that the shaft 204b can rotate.
However, the input gear 201 and the output portion 204 are prevented from coming off in the thrust direction. The lower half of the clutch spring 202
Is wound around the output cylinder 204c. Then, the flat bent portion 202a at the upper end of the spring is engaged with the groove 203a of the collar member 203,
The point that the three-dimensional bent portion 202c at the lower end of the spring is inserted into the groove 204d of the output portion 204 is the same as in the first embodiment.

In this embodiment, when the clutch spring 202 is free similarly to the first embodiment, the inner diameter of the helix 202b is changed from the output side as shown in FIG. 9B. It is characteristic that it has a tapered shape gradually expanding toward the input gear. That is, the relationship between the clutch spring diameter d1 on the input gear side, the clutch spring diameter d2 on the output side, and the input body diameter Din is Din>d1> d2, and the difference between d1 and d2 is about 0.05 mm. Note that, also in the present embodiment, the tightening allowance is set to fall within a range of 0.1 mm to 0.3 mm.

The effect of this embodiment is the same as that of the first embodiment. However, in the present embodiment, the rotation speed is lower than 100 rpm as compared with the first embodiment, but the torque required for the output unit 204 is very high because the feed roller 53 in contact with the separation pad 60 is rotated. In the present embodiment, since the clutch spring 202 is tapered, it is possible to reduce the pressure of the flat bent portion 202a, which is a disturbance factor, and to obtain a sufficient allowance for the portion near the output side.

In this embodiment, it is needless to say that the input gear described in the second embodiment may be used.

Although the present invention has been described with respect to a spring clutch which turns ON / OFF a driving force by regulating a collar member by a solenoid, the present invention may be applied to a clutch which does not use a solenoid, such as a one-way spring clutch. .

[0051]

As described above, according to the present invention, by making the spring of the spring clutch tapered, the pressure at the portion where the impact is easily transmitted can be reduced, and the impact energy due to stick-slip can be reduced. In addition, by gradually changing the pressure applied to the input cylinder of the clutch spring, the co-rotating force (frictional force) can be gradually changed. Also, the spring return force gradually changes because the tightening allowance changes.

Therefore, the frequency of each point of the spring at the time of stick-slip changes, resonance is less likely to occur, and a spring clutch with an increased margin for noise change during idling can be provided. It is possible to provide an inexpensive image forming apparatus such as a transport device and a printer or a copier including the transport device.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a laser beam printer as an image forming apparatus according to a first embodiment.

FIG. 2 is an explanatory diagram of a stay, a spring clutch, and the like as viewed from the left side of FIG. 1;

FIG. 3 is an explanatory main sectional view of a spring clutch.

FIG. 4 shows a spring clutch, (a) is an exploded view, and (b)
FIG. 3 is an explanatory view taken along the line AA in FIG.

FIG. 5 is a diagram for explaining a mechanism of a sound change that may occur from a spring clutch.

FIG. 6 shows a spring clutch according to a second embodiment, and (a)
FIG. 3 is an exploded view, and FIG. 3B is an explanatory view taken along the line AA in FIG.

FIG. 7 is a schematic sectional view of a laser printer of another type different from the first embodiment.

FIG. 8 is an exploded perspective view illustrating a feeding unit including a feeding roller.

9A and 9B show a spring clutch of the present embodiment, wherein FIG. 9A is a sectional view and FIG. 9B is an explanatory view of a clutch spring.

FIG. 10 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 P ... Sheet 1 ... Image forming apparatus 2 ... Image forming section 3 ... Sheet re-feeding / conveying section 4 ... Feeding section 5 ... Switchback roller 6 ... Horizontal registration correcting section 7 ... Reference plate 8 ... Roller 9 ... Slanting feeding roller 10 … Convey detection means 11… Arm member 12… Photo sensor 13… Re-feed reversal guide 14… Sheet discharge section 15… Sheet discharge table 16… Controller boards 17, 18… Gear 19… Stay 20… Axis 21… Solenoid 22… Solenoid Armature 23… Roller drive gear 51… Laser printer 52… Sheet loading table 53… Feed roller 54… Image forming unit 55… Discharge unit 56… Rollers 58,59… Cam 60… Separation pad 61… Separation pad urging means 62 , 63 ... Arm 64 ... Middle plate 65 ... Urging means 66 ... Solenoid 66a ... Solenoid armature 67 ... Shaft 100 ... Spring clutch 101 ... Input gear 101a ... Gear part 101b ... Input cylinder 102 ... Clutch spring 102 a ... Plane bending part 102b ... Hanging part 102c ... Three-dimensional bending part 103 ... Collar member 103a ... Groove 103b ... Groove 104 ... Output gear 104a ... Locking projection 104b ... Shaft 104c ... Output cylinder 104d ... Groove 200 ... Spring clutch 201 ... Input gear 201a ... gear part 201b ... input cylinder 202 ... clutch spring 202a ... plane bending part 202b ... helical part 202c ... three-dimensional bending part 203 ... collar member 203a ... groove 203b ... projection part 204 ... output part 204a ... locking projection 204b … Shaft 204c… output cylinder 204d… groove 204e… groove

Continued on the front page F term (reference) 3F049 AA10 EA01 EA10 LA02 LA05 LA07 LB03 3F100 AA02 3F343 FA02 FB04 GA04 GB01 GC01 GD01 JA01 KB04 LD29 3J056 AA47 BA01 BB15 BE28 CA01 DA04 GA26 GA27

Claims (8)

[Claims] 1. A rotatable input section for inputting a driving force, a rotatable output section for outputting a driving force, and an input cylinder formed on the input section and an output cylinder formed on the output section. The input cylinder and the output cylinder are connected by the coil spring being tightened, the driving force is transmitted and the driving force is transmitted, and the input cylinder and the output cylinder are connected by loosening the coil spring. A spring clutch in which the connection is released and the driving force is not transmitted, wherein the inner diameter of the coil spring is gradually changed to have a tapered shape. 2. A rotatable input section for inputting a driving force, a rotatable output section for outputting a driving force, and an input cylinder formed on the input section and an output cylinder formed on the output section. A spring clutch having a coil spring which is attached by rotation and a locking member at which one end of the coil spring is locked, and which transmits a driving force from the input section to the output section by locking and unlocking the locking member. 3. The spring clutch according to claim 1, wherein an inner diameter of the coil spring is tapered such that an inner diameter of the coil spring gradually decreases from the input unit side to the output unit side. 3. The spring clutch according to claim 2, wherein the outer diameter of the input cylinder has a tapered shape that gradually increases from the input portion side to the output portion side. 4. A rotatable input section to which a driving force is input, a rotatable output section to output a driving force, and an input cylinder formed at the input section and an output cylinder formed at the output section. A spring clutch having a coil spring which is attached by rotation and a locking member at which one end of the coil spring is locked, and which transmits a driving force from the input section to the output section by locking and unlocking the locking member. 3. The spring clutch according to claim 1, wherein an outer diameter of the input cylinder has a tapered shape that gradually increases from the input section side to the output section side. 5. A sheet conveying apparatus for conveying a sheet by a conveying rotating body, wherein the spring clutch according to claim 1 is used for transmitting a driving force to the conveying rotating body. A sheet conveying device. 6. A first sheet conveying path, comprising: a first sheet conveying path, a second sheet conveying path, and a conveying rotator for conveying a sheet into the second sheet conveying path. A sheet conveying apparatus capable of stopping the conveying rotating body and allowing the second sheet in the second conveying path to stand by when the first sheet is passing through, the driving of the conveying rotating body A sheet conveying device using the spring clutch according to any one of claims 1 to 4 for ON / OFF of transmission. 7. A sheet conveying apparatus for rotating a feed roller to feed a sheet to a predetermined position and then stopping the rotation of the feed roller, wherein the drive transmission of the feed roller is turned on and off. A sheet conveying device using the spring clutch according to claim 4. 8. An image forming apparatus for forming an image by conveying a sheet, the sheet conveying apparatus according to claim 5, and an image formed on a sheet conveyed by the sheet conveying apparatus. An image forming apparatus, comprising: an image forming unit to be formed;