JP2001323966A - Torque transmitting mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce uneven torque transmission, prevent a load increase resulting from axial thrust force caused during a gear rotation, and facilitate the mounting of the gears on studs, in a torque transmitting mechanism using the gears rotatably supported on the studs. SOLUTION: The torque transmitting mechanism D1, D2 has pairs/a pair of helical gears G2a, G2b, G4a and G4b; G8a and G8b rotatably supported on the same shafts/shaft in an adjacent relation and oppositely twisted so as to produce thrust force in the direction to press them to each other when rotated, and a double-helical gear G3; G7 meshed with the pairs/pair of helical gears G2a, G2b, G4a and G4b; G8a and G8b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque transmitting mechanism using gears, and more particularly to a torque transmitting mechanism using a helical gear and a helical gear.

[0002]

2. Description of the Related Art Hitherto, a rotational force transmitting mechanism using a gear is known in various technical fields, and is used, for example, for transmitting a rotational force to a sheet take-out roll of an image forming apparatus. FIG. 9 is an explanatory view of a rotational force transmission mechanism using a conventional gear. In a transfer area where a toner image formed on a photosensitive drum of a copying machine (image forming apparatus) is transferred to a recording sheet, a paper feed cassette is provided. FIG. 4 is a diagram illustrating a mechanism for transmitting a rotational force to a sheet conveying roll for taking out and conveying the sheet. A torque transmitting mechanism similar to the torque transmitting mechanism shown in FIG. 9 is described in JP-A-9-196152, JP-A-9-328235, and the like.
In order to facilitate understanding of the following description, in this specification and the drawings, the front-rear direction is the X-axis direction, the right-left direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X,
The directions or sides indicated by Y, -Y, Z, and -Z are front, rear, right, left, upper, lower, or front, rear, right, left, upper, and lower, respectively. Also, in the figure, those with “•” in “○” mean arrows pointing from the back of the paper to the front, and those with “x” in “○” indicate the arrow on the paper. From the back to the back.

In FIG. 9, a sheet feeding device 01 used in an image forming apparatus such as a copying machine has a pickup roll 02.
And a feed roll 03 and a retard roll 04 as a sheet feeding member for conveyance. The shaft 03a of the feed roll 03 is driven to rotate by a paper feed motor (not shown) disposed at the rear of the image forming apparatus. A pick-up roll shaft 02a, which rotates integrally with the pick-up roll 02, is rotatably supported on the swing plate 05 rotatably supported by the feed roll shaft 03a. As can be seen from FIG. 9, when the gear G1 fixed to the feed roll shaft 03a rotates, the gears G2, G3, and G4 supported by the swing plate 05 rotate in conjunction with each other, and further mounted on the pickup roll shaft 02a. The rotated gear G5 rotates. Therefore, the gears G1 to G
Reference numeral 5 denotes a rotational force transmitting mechanism (G1 to G5) for transmitting the rotation of the feed roll shaft 03a to the pickup roll shaft 02a.
Is composed. When the swinging plate 05 takes out the sheet S stored in a sheet feeding cassette (not shown), the feed roller shaft 03a is driven by gravity and a weak spring (not shown).
The sheet S is configured to descend around and come into contact with the upper surface of the sheet S.

The lower surface of the raising / lowering control projection 05a (see FIG. 9) of the swinging plate 05 is supported by a raising / lowering rotating lever 07 which rotates integrally with the arm raising / lowering shaft 06.
The arm elevating shaft 06 is configured to rotate by a certain angle in the direction of arrow A in accordance with expansion and contraction of a solenoid (not shown). As can be seen from FIG. 9, the arm raising / lowering shaft 06 is rotated in the direction of the arrow A around the axis to hold the raising / lowering rotating lever 07 at the raised position when the solenoid (not shown) is off, and the solenoid is turned on. In the case of, the lift lever 07 is held at the lowered position. In a state where the lift lever 07 is held at the lowered position, the swing plate 05 swings downward by gravity and a spring (not shown), and the pickup roll 02 comes into contact with the upper surface of the sheet S.

In FIG. 9, a swinging plate 05 is provided with a position control projecting piece 05b extending rightward (Y direction). The position control projecting piece 05b moves up and down according to the swing of the swing plate 05. A swing arm posture sensor S including a light emitting element SNa and a light receiving element SNb is arranged at a position sandwiching the movement path of the position control projecting piece 05b from the front-back direction (X-axis direction). When the swing posture of the swing plate 05 falls below a predetermined position, the position control projecting piece 05b moves downward between the light emitting element SNa and the light receiving element SNb, and the swing arm posture sensor S is turned off. It is configured to be ON.

In FIG. 9, below the feed roll 03, there is provided a swing support member 09 swingable about a swing shaft 08 which is non-rotatably supported. A retard roll shaft 04a that rotates integrally with the retard roll 04 is rotatably supported by the swing support member 09. FIG.
, A gear G6 is mounted on the retard roll shaft 04a. A gear support bracket 010 is supported by the swing support member 09, and the gear support bracket 01
At 0, studs 010a and 010b are provided to protrude. The studs 010a and 010b have a gear G
7, G8 are rotatably supported. The swing support member 09 is provided with a rotational force about a swing axis 08 by a tension spring 011. The retard roll 04 is pressed against the feed roll 03 by the action of the tension spring 011.

[0007] A torque limiter 012 is mounted on the swing shaft 08 which is non-rotatably supported. In FIG. 9, the torque limiter 012 is arranged to be rotatable while receiving a frictional resistance around an output hub (not shown) fixed to the non-rotatable swing shaft 08 and the output hub. It has an input hub 012a. When the gear G6 fixed to the retard roll shaft 04a rotates, the gears G7 and G8 supported by the gear support bracket 010 and the gear G9 fixed to the input hub 012a rotate in conjunction with the rotation of the gear G6. Therefore, the gears G6 to G9 constitute a torque transmitting mechanism (G6 to G9) for transmitting the rotation of the retard roll shaft 04a to the input hub 012a. The gear G9 has a cylindrical portion G9a.
A pin G9b is provided on the cylindrical portion G9a.

[0008] The retard roll 04 pressed against the rotatably driven feed roll 03 rotates in conjunction with the feed roll 03. At this time, the axis 0 of the retard roll 04
The input hub 012a that rotates via the gears G6 to G9 linked to 4a rotates while receiving frictional resistance around the fixed output hub (not shown). At this time, since the braking force acts on the input hub 012a, the braking force also acts on the retard roll 04. Therefore, when the sheet is not conveyed to the press-contact portion of the feed roll 03 and the retard roll 04, the retard roll 04 is interlocked with the feed roll 03, but receives the frictional resistance from the torque limiter 012. The pickup roll 02
, Two sheets S are simultaneously taken out of the sheet feed tray, and the feed roll 03 and the retard roll 04
, The upper sheet S is conveyed by the feed roll 03, but the lower sheet S is subjected to frictional resistance by the retard roll 04, so that only the upper sheet S is fed.

[0009]

In the paper feeder 01, when the torque transmitting mechanism (G6 to G9) is constituted by a spur gear, an impact is generated at the start of gear engagement, and the torque transmission unevenness occurs. There is a problem that. FIG.
Reference numeral 0 is a plan view of a case where a helical gear is used instead of the helical gear used for the gears of the rotational force transmission mechanism (G6 to G9) in FIG. As shown in FIG. 10, when a helical gear is used as a gear of the rotational force transmission mechanism (G6 to G9), a feed motor (not shown) that drives the feed roll shaft 03a steps out. Trouble may occur. One of the causes is a torque transmitting mechanism (G6 to G9) between the torque limiter 012 for generating a rotational frictional force on the retard roll 04 and the retard roll 04.
There is an increase in the load.

The helical gear generates an axial thrust force and moves in the axial direction, and frictionally comes into contact with a retaining member such as a clip to generate resistance. As a result, a transmission loss of the driving force occurs, so that the load applied to the feed motor, which is the driving source, increases, and if a load exceeding the power of the motor occurs, the motor loses synchronism. To solve the above problems, the following methods (1) and (2) are conceivable. (1) Make the motor more powerful. (2) A lubricant such as grease is applied to a contact portion between the gear and the gear retaining member (C clip or the like). Powering up the motor has a problem that the motor needs to be upsized. For this reason, it may not be used for an existing unit having a fixed outer shape. When the lubricant is applied, when the lubricant is used up, it becomes necessary to apply the lubricant several times before the life of the image forming apparatus.

In order to solve the above problem, in the rotational force transmitting mechanism (G6 to G9), a helical gear is used in place of the helical gear shown in FIG. 10 and an axial thrust acting on the gear is used. It is known in the art to cancel forces and minimize drive power losses. FIG. 11 is an explanatory diagram in the case where the yamato gear is mounted on each of the two studs 010a and 010b. In FIG. 11, when the gears G7, G8 are helical gears, the helical gears having different directions are integrally formed, so that the studs (gear mounting shafts) 010a, 0
When the gears G7 and G8 are fitted in the gear 10b, there is a problem that the teeth of the adjacent gears hinder the assembly and are difficult to assemble. If there are two studs (gear mounting shafts), it is possible to mount them on the two studs (gear mounting shafts) at the same time in a state in which the two yamato gears are engaged. As the number of gears increases, it becomes difficult to mount the gear on the stud.

In view of the above circumstances, the present invention provides the following (O01)
The contents of (O03) shall be the subject. (O01) In a torque transmitting mechanism using a gear rotatably supported by a stud, uneven transmission of torque is reduced. (O02) To prevent an increase in load due to an axial thrust force generated when the gear rotates. (O03) To facilitate mounting of gears on studs.

[0013]

Next, the present invention will be described. Elements of the present invention are indicated by parentheses in the elements of the embodiments in order to facilitate correspondence with the elements of the embodiments described later. Add the enclosed items. The reason why the present invention is described in correspondence with the reference numerals of the following embodiments is to facilitate understanding of the present invention, and not to limit the scope of the present invention to the embodiments.

(Solution of the Invention) In order to solve the above-mentioned problems, a rotation force transmission mechanism (D1, D2) of the invention is rotatably supported in a state of being axially overlapped on the same axis and pressed against each other during rotation. A pair of helical gears (G2a, G2b, G4a, G
4b; G8a, G8b) and the pair of helical gears (G
2a, G2b, G4a, G4b; G8a, G8b) and a bevel gear (G3; G7).

(Operation of the Present Invention) In the rotational force transmitting mechanism of the present invention having the above-described structure, a thrust force is generated in a direction in which the rotational force is rotatably supported on the same shaft so as to be axially overlapped with each other and pressed against each other during rotation. Helical gears (G2a, G2b, G4a, G4b; G8a,
G8b) and the pair of helical gears (G2a, G2b,
G4a, G4b; G8a, G8b) and a skein gear (G3; G7) that meshes with the gears, so that uneven transmission of rotational force can be reduced as compared with the case where a helical gear is used. Also, the tooth gears (G2a, G2b, G4a, G4b; G4) that apply the rotational force of the yamato gear (G3; G7)
8a, G8b), the helical gears (G2a, G8b)
2b, G4a, G4b; G8a, G8b) do not move toward the axial end, so that the helical gears (G2a, G2b,
G4a, G4b; G8a, G8b) can be prevented from galling between another member (a member supporting the shaft or a gear retaining member such as a clip mounted on the shaft). Therefore, it is possible to prevent a load increase due to an axial thrust force generated when the gear rotates.
Driving force loss can be reduced. A pair of helical gears (G2a, G2b, G4a, G4b; G8a, G8
b) one of the helical gears (G2a, G4a; G8
a) is replaced with a stud (gear mounting shaft) (6a, 6c; 11b)
With the stud (gear mounted shaft) (6
b; 11a) and the helical gears (G2a, G4a; G8).
A mountain gear (G3; G7) meshing with a) can be mounted. In this state, the helical gears (G2a, G4
a; stud (gear mounting shaft) with G8a) mounted thereon (6
a, 6c; 11b) on the helical gears (G2a, G4).
a; another helical gear (G
2b, G4b; G8b) is connected to the aforementioned bevel gear (G3; G
7) It can be mounted in a state of meshing. That is, studs (6a, 6b, 6c;
11a, 11b), a pair of helical gears (G2a, G2
b, G4a, G4b; G8a, G8b) and the bevel gears (G3; G7) meshing with them can be easily mounted.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1 of the present invention) The rotational force transmitting mechanism of Embodiment 1 of the present invention is the same as that of the present invention, except that the pair of helical gears and the pair of Helical gears (G2a, G2b, G4a, G4b; G8a, G8
idler gear trains (G2 to G4; b) arranged so as to alternately mesh with the mountain gears (G3; G7) meshing with each other.
G7, G8).

(Operation of the First Embodiment of the Present Invention) The idler gear train (G2 to G4; G7, G8) of the rotational force transmitting mechanism having the above-described configuration according to the first embodiment of the present invention has a pair of coaxial shafts. Helical gears (G2a, G2b, G4a, G4b;
G8a, G8b) and the pair of helical gears (G2a, G8a).
2b, G4a, G4b; G8a, G8b) are arranged so as to alternately mesh with the dovetail gears (G3; G7), so that a pair of helical gears (G2a, G2b, G4)
a, G4b; G8a, G8b), one of the helical gears (G2a, G4a; G8a) is mounted on each stud (gear mounting shaft) (6a, 6c; 11b), and the helical gears are mounted. Each bevel gear (G3; G7) is mounted so as to mesh with the tooth gear (G2a, G4a; G8a), and then the other helical gear (G3) is meshed with the respective bevel gear (G3; G7). G2b, G4b; G8b). That is, the studs (6
a, 6b, 6c; 11a, 11b), a pair of helical gears (G2a, G2b, G4a, G4b; G8a, G8).
b) and mountain gears meshing with them (G3; G7)
Can be easily mounted.

EXAMPLES Next, specific examples (examples) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples. (Embodiment 1) FIG. 1 is an overall explanatory view of an image forming apparatus and a sheet feeding member according to an embodiment of the present invention. In FIG. 1, an image forming apparatus (digital copying machine) U according to an embodiment includes an image forming apparatus main body U1 and an automatic document feeder U2. The image forming apparatus main body U1 has an IOT (image output terminal) and an IIT (image input terminal, that is, an image reading unit). The automatic document feeder U2 is supported on a platen glass PG on the upper surface of the IIT. A sheet discharge tray TRh is provided between the upper surface of the IOT and the upper IIT.

In FIG. 1, the automatic document feeder U2
Has a document feed tray TG1 on which a plurality of documents Gi to be copied are placed in an overlapping manner. The plurality of originals Gi placed on the original feed tray TG1 sequentially pass through the copy position on the platen glass PG and pass through the original discharge tray T1.
It is configured to be discharged to G2. The automatic document feeder U2 is rotatable with respect to the upper surface of the platen glass PG by a hinge shaft (not shown) extending in the left-right direction provided at a rear end (-X end) of the automatic document feeder U2. When the person puts on the platen glass PG by hand, it is turned upward. The image forming apparatus main body U1 has a UI (user interface) through which a user inputs an operation command signal such as copy start.

An exposure optical system A for reading a document image is disposed below the transparent platen glass PG. Reflected light from a document conveyed to the upper surface of the platen glass PG by the automatic document feeder U2 or a document (not shown) manually placed on the platen glass PG is transmitted through the exposure optical system A to the CCD (CCD). It is converted into an electric signal by a solid-state imaging device. An IPS (image processing system) converts an RGB electrical signal input from a CCD into image data, temporarily stores the image data, and converts the image data at a predetermined timing as image data for forming a latent image into a laser driving circuit DL. Output to The laser drive circuit DL outputs a laser drive signal to a ROS (latent image forming apparatus) according to the input image data. The UI (user interface), IPS and laser drive signal output device D
L and the operation of a power supply circuit E for applying a bias voltage to the developing roll Ga and the transfer roll TR described later are controlled by the control C.
Is controlled by

Image carrier P constituted by a photosensitive drum
R rotates integrally with its axis PRa in the direction of the arrow (clockwise in FIG. 1), and its surface is uniformly charged by the charging roll CR.
An electrostatic latent image is formed by being exposed and scanned by the laser beam L of S (latent image forming apparatus). The surface of the image carrier PR on which the electrostatic latent image is formed is rotated and sequentially moved to the developing area (the area facing the developing roll Ga) and the transfer area (the transfer roll T).
(Area facing R) Q1. The developing device G has a developing container V that rotatably supports the developing roll Ga and the developer stirring members Gb, Gc, and Gd and stores the developer, and on the image carrier PR passing through the developing area. The electrostatic latent image is developed into a toner image.

The plurality of paper feed trays TR1 to TR4 (see FIG. 1) accommodate recording sheets S to be conveyed to the transfer area Q1, and are disposed on both left and right sides (both sides in the Y-axis direction) in the front-rear direction. It is movably supported along a pair of rails RL1 and RL1 arranged along a direction perpendicular to the plane of FIG. FIG. 2 is an enlarged explanatory view of a main part of a sheet feeding member of the image forming apparatus of the present embodiment. 1 and 2, a sheet feeding device K provided above the sheet feeding side of each of the sheet feeding trays TR1 to TR4 includes a pickup roll Rp, a feed roll Rs1 and a retard roll Rs2, and members for driving them ( (Described later). The recording sheets S picked up by the pickup rolls Rp of the sheet feeding device K are separated one by one by a separation roll Rs having a feed roll Rs1 and a retard roll Rs2, and a plurality of sheets arranged along the sheet conveyance path SH. Conveyance roll R
a, and at a predetermined timing by the registration roll Rr (see FIG. 1) to the transfer area Q1.
The recording sheet S fed from the manual feed tray TR0 is also conveyed to the transfer area Q1 by the sheet conveying roll Ra and the registration roll Rr arranged along the sheet conveying path SH.

In FIG. 1, a transfer roll TR to which a transfer bias is applied is disposed in the transfer area Q1. The transfer roll TR is in pressure contact with the image carrier PR in the transfer area Q1, and transfers the toner image on the image carrier PR to the recording sheet S passing through the transfer area Q1. After the toner image on the surface of the image carrier PR is transferred to the recording sheet S in the transfer area Q1, the residual toner adhered to the surface of the image carrier PR is collected by the cleaner CL.
The image carrier PR from which the residual toner adhered to the surface by the cleaner CL is collected is charged by the charging roll CR.

The recording sheet S to which the unfixed toner image has been transferred in the transfer area Q1 is conveyed to the fixing area Q2 in a state where the toner image has not been fixed, and a pair of fixing devices F arranged in the fixing area Q2. The toner images are fixed by the fixing rolls Fh and Fp. Thereafter, the recording sheet S on which the fixed toner image is formed is guided by a sheet guide, and is conveyed to a discharge roll (standard discharge roll) R1. The discharge roll (standard discharge roll) R1 is an upper discharge drive roll R1.
a and a lower discharge driven roll R1b. The recording sheet S is discharged to the sheet discharge tray TRh by the discharge roll R1.

In FIG. 2, the sheet trays TR1 and TR2 arranged in multiple stages of the image forming apparatus according to the first embodiment rise outside the sheet front end support wall 1 at the front end (left end in FIG. 2) in the sheet feeding direction. One end of an L-shaped lift lever 3 is fixed to the lift rotary shaft 2.
The other end of the lifting lever 3 is in contact with the lower surface of the sheet mounting plate 4, and a sheet (recording sheet) S is mounted on the upper surface of the sheet mounting plate 4. When the sheet feeding trays TR1 and TR2 containing the sheets S are stored in the image forming apparatus, the rotation shaft 2 for rotation rotates, and the lifting lever 3 lifts the sheet placement plate 4 to move the sheet upper surface position. It is configured to hold in place.

FIG. 3 shows a sheet taken out of a sheet cassette into a transfer area where a toner image formed on a photosensitive drum of the copying machine (image forming apparatus) shown in FIGS. FIG. 5 is a diagram showing a mechanism for transmitting a rotational force to a sheet conveying roll for conveying the sheet. FIG.
FIG. 4 is a detailed explanatory view of a main part shown in FIG. 3 and 4, the sheet feed tray TR1
The axis Rs1a of the feed roll Rs1 of the sheet feeding device K provided on the upper side of the sheet feeding side is rotated by a sheet feeding motor M arranged at the rear of the image forming apparatus. A bearing B is attached to the feed roll shaft Rs1a (see FIGS. 3 and 4).
The pick-up roll shaft Rpa, which rotates integrally with the pick-up roll Rp, is rotatably supported via a bearing B (see FIG. 4) on the swinging plate 6 rotatably supported through the pick-up roll Rp. The position of the bearing B with respect to the pickup roll shaft Rpa is regulated by a C-shaped or E-shaped clip C (see FIG. 4).

In FIGS. 3 and 4, a helical gear G1 is mounted on the feed roll shaft Rs1a, and a helical gear G5 is mounted on the pickup roll shaft Rpa.
Studs (gear mounting shafts) 6a, 6b, 6c are provided on the front side surface (X side surface) of the swing plate 6 so as to protrude forward. A gear G2 having a pair of helical gears G2a and G2b that are pressed against each other while rotating in the opposite direction with respect to the twist direction is rotatably mounted on the stud 6a. A mountain gear G3 is mounted on the stud 6b. The stud 6c is provided with a gear G4 having a pair of helical gears G4a and G4b that are pressed in rotation when rotating in opposite directions. The positions of the gears G2 to G4 on the studs 6a to 6c are regulated by clips C for retaining.

As can be seen from FIG. 3, when the gear G1 fixed to the feed roll shaft Rs1a rotates, the gears G2, G3, G4 supported on the swing plate 6 rotate in conjunction with each other, and further, the pickup roll shaft The gear G5 mounted on Rpa rotates. Therefore, the gears G1 to G5
Is a torque transmitting mechanism D1 (= G1 to G1) for transmitting the rotation of the feed roll shaft Rs1a to the pickup roll shaft Rpa.
5).

The lower surface of the elevation control projection 6d (see FIG. 3) provided on the swing plate 6 is supported by an elevation rotary lever 7a that rotates integrally with the arm elevation shaft 7.
The arm elevating shaft 7 is configured to be rotated by a certain angle in the direction of arrow A in accordance with the expansion and contraction of a solenoid (not shown). As can be seen from FIG. 3, the arm elevating shaft 7 holds the elevating rotary lever 7a at the ascending position when the solenoid (not shown) is off by rotating the arm elevating shaft 7 around the axis in the direction of the arrow A, and the solenoid is turned on. In this case, the lift lever 7a is held at the lowered position by gravity and a weak spring (not shown). In a state in which the lifting / lowering rotary lever 7a is held at the lowered position, the pickup roll Rp is moved to the sheet feeding tray TR1.
The sheet contacts the upper surface of the sheet S accommodated in the TR4.

In FIG. 3, the swing plate 6 is provided with a position control projection 6e extending in the right direction (Y direction). The position control protrusion 6 e moves up and down in accordance with the swing of the swing plate 6. The position control protrusion 6e
A swing arm posture sensor SN including a light emitting element SNa and a light receiving element SNb is disposed at a position sandwiching the moving path of the light emitting element SNa from the front-back direction (X-axis direction). When the rocking posture of the rocking plate 6 falls below a predetermined position, the position control projecting piece 6e is moved by the light emitting element SNa and the light receiving element S
It is configured to move downward between Nb and turn the swing arm attitude sensor SN from OFF to ON.

In FIG. 3, the feed roll Rs1
A swing support member 9 is swingably supported via bearings B and B around a swing shaft 8 that is non-rotatably supported below the shaft. FIG. 6 is a detailed explanatory view of a main part shown in FIG. 3 and is a top view of the rotational force transmission mechanism D2. 3 and 6, a support shaft Rs2b is supported on the swing support member 9, and a cylindrical retard roll shaft Rs2a that rotates integrally with the retard roll Rs2 is rotatably supported on the support shaft Rs2b. Have been. The swing support member 9 is provided with a swing shaft 8 by a tension spring 10 provided between the swing support member 9 and a fixed frame.
A rotational force is applied around the periphery. The retard roll Rs2 is pressed against the feed roll Rs1 by the action of the tension spring 10.

A gear G6 is attached to the retard roll shaft Rs2a.
Is installed. A gear support bracket 11 is supported by the swing support member 9, and the gear support bracket 1
1 is provided with studs 11a and 11b projecting therefrom. Gears G7, G8 are rotatably supported by the studs 11a, 11b. The gear G7 mounted on the stud 11a of the gear support bracket 11 supported by the swing support member 9 is a helical gear, and the gear G8 mounted on the stud 11b is a pair of helical gears G8a, G8b.
(See FIG. 6).

The swinging shaft 8 which is non-rotatably supported has:
A torque limiter 12 is mounted. In FIG.
The torque limiter 12 includes an output hub (not shown) fixed to the non-rotatable swing shaft 8 and an input hub 12a rotatably disposed around the output hub while receiving frictional resistance. Have. A pin locking groove is formed in the input hub 12a,
A cylindrical portion G9 fixed to the gear G9 is provided in the pin locking groove.
a is fitted, and a pin G9b provided on the cylindrical portion G9a is locked. Therefore, the input hub 12a and the gear G9 rotate integrally. The retard roll axis R
When the gear G6 fixed to s2a rotates, the gears G7, G8 and the gear G9 fixed to the input hub 12a rotate in conjunction with the rotation of the gear G6. Therefore, the gears G6 to G9 constitute a torque transmitting mechanism D2 (= G6 to G9) for transmitting the rotation of the retard roll shaft Rs2a to the input hub 12a.

In FIG. 3, the retard roll Rs2 pressed against the rotationally driven feed roll Rs1 rotates in conjunction with the feed roll Rs1. At this time, the input hub 12a rotating via the gears G6 to G9 interlocking with the shaft Rs2a of the retard roll Rs2 rotates while receiving frictional resistance around the fixed output hub (not shown). At this time, since a braking force acts on the input hub 12a, a braking force also acts on the retard roll Rs2. Therefore, in a state where the sheet S is not conveyed to the press-contact portion of the feed roll Rs1 and the retard roll Rs2, the retard roll R
Although s2 rotates in conjunction with the feed roll Rs1, it receives frictional resistance from the torque limiter 12. The sheet S is moved from the sheet feeding tray by the pickup roll Rp.
When two sheets S are taken out at the same time, and two sheets S, S are conveyed to the press-contact portion of the feed roll Rs1 and the retard roll Rs2, the upper sheet S is conveyed by the feed roll Rs1, Is subjected to frictional resistance by the retard roll Rs2, so that only the upper sheet S is fed.

In FIG. 2, the feed roll Rs1
The sheet S separated one by one by the retard roll Rs2 and sent to the sheet conveying path SH on the sheet feeding end side of the sheet feeding tray TR includes a plurality of sheets S provided on the sheet conveying guide 13 of the sheet conveying path SH. It is transported upward by the transport roll Ra. The sheet conveyance guide 13 has an outer guide member 13a and an inner guide member 13b, and the outer guide member 13a is configured to be separated from the inner guide member 13b. In a state where the outer guide member 13a is separated from the inner guide member 13b, the jammed sheet S in the sheet conveyance path SH is easily taken out.

FIG. 5 is an explanatory view of an assembling method of the rotational force transmitting mechanism D1. FIG. 5A is a diagram showing a helical gear mounted on both sides of a stud for mounting a helical gear. FIG. 5B is a view showing a state in which a helical gear is mounted on a stud for mounting, and FIG. 5B is a diagram showing a state in which the helical gear is mounted on the stud for mounting the helical gear after the helical gear in FIG. 5A is mounted. FIG. 5C is a diagram showing a state in which the helical gears are mounted so as to mesh with the helical gears. The helical gears are mounted on the helical gear mounting studs on both sides of the yamagear gear mounting stud after the yamagear gear of FIG. 5B is mounted. FIG. 5D is a view showing a state of being mounted so as to mesh with the yamato gear, and FIG.
The helical gears G1 and G
FIG. 5 is an explanatory diagram of a method of assembling the helical gear 5 with the helical gears G2 and G4.

In FIG. 5A, the helical gears G2a, G2 are respectively mounted on the helical gear mounting studs 6a, 6c arranged on both sides of the helical gear mounting stud 6b.
4a is attached. Next, in FIG. 5B, the helical gear G3 is mounted on the helical gear mounting stud 6b so as to mesh with the helical gears G2a and G4a. next,
In FIG. 5C, helical gear mounting studs 6a, 6c
The helical gears G2b and G4b are mounted so as to mesh with the helical gear G3. Next, in FIG. 5D,
The feed roll shaft Rs1a is passed through the through hole of the helical gear G1 in a state where the helical gear G1 is held so as to mesh with the helical gear G2 (a state in which the helical gear G1 is held by an operator). Assemble as shown in FIG. Further, the pickup roll shaft Rpa is passed through the through-hole of the helical gear G5 in a state where the helical gear G5 is held so as to mesh with the helical gear G4 (a state in which the helical gear G5 is held by an operator). 3. Assemble as shown in FIG. The rotational force transmission mechanism D1 has the helical gear G3 and the helical gears G2, G4 having a pair of helical gears (G2a, G2b or G4a, G4b) alternately arranged. The G4 can be easily assembled so as to be engaged with each other.

FIG. 7 is an explanatory view of an assembling method of the rotational force transmitting mechanism D2. FIG. 7A is a diagram illustrating a helical gear mounting stud disposed adjacent to a helical gear mounting stud. FIG. 7B is a view showing a state in which a gear is mounted, and FIG. 7B is a view showing a state in which the helical gear of FIG. 7A is mounted and then the helical gear is mounted on the stud for mounting the helical gear so as to mesh with the helical gear. FIG. 7C shows the helical gear mounted on the helical gear mounting stud adjacent to the helical gear mounting stud after the helical gear of FIG. 7B is mounted so as to mesh with the helical gear. It is a figure showing a situation.

In FIG. 7A, a helical gear G8a is mounted on a helical gear mounting stud 11b arranged adjacent to a helical gear mounting stud 11a. Next, in FIG. 7B, the helical gear G7 is mounted on the helical gear mounting stud 11a so as to mesh with the helical gear G8a. Next, in FIG. 7C, the helical gear G8b is mounted on the helical gear mounting stud 11b so as to mesh with the helical gear G7. This rotational force transmission mechanism D
2 uses a helical gear G8 having a pair of helical gears G8a and G8b and a helical gear G7, so that the gears G7 and G8 can be easily assembled in a state where they mesh with each other.

FIG. 8 shows that the helical gears G6 and G9 are mounted on the helical gear G7 after the helical gear of FIG.
FIG. 9 is an explanatory diagram of a method of assembling so as to mesh with the helical gear G8. In FIG. 8, the support shaft Rs2b is held in a state in which the helical gear G6 mounted on the cylindrical retard roll shaft Rs2a is held so as to mesh with the helical gear G7 (a state held by a worker's hand). It is made to penetrate the inner hole of the cylindrical retard roll shaft Rs2a, and assembled in the state of FIG. In FIG. 8, the bearing B mounted on the rocking support member 9 is penetrated in a state where the yama gear G9 is held so as to mesh with the helical gear G8 (a state held by an operator's hand). The oscillating shaft 8 is passed through the through hole of the helical gear G9, and the torque limiter 1
The output hub (not shown) inside the second input hub 12a and another bearing B are penetrated and assembled as shown in FIG.

(Modifications) Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, but falls within the scope of the present invention described in the appended claims. Thus, various changes can be made. Modified embodiments of the present invention will be exemplified below. (H01) The present invention can be applied to a rotational force transmission mechanism using a gear train in various apparatuses other than the image forming apparatus.

[0042]

The above-described torque transmitting mechanism of the present invention has the following effects. (E01) Since the helical gear and the helical gear are used in the rotational force transmitting mechanism using the gear rotatably supported by the stud, it is possible to reduce the uneven transmission of the rotational force. (E02) As the helical gear, a pair of helical gears that are rotatably supported on the same shaft in an axially overlapping state and twisted in opposite directions so as to generate a thrust force in a direction of pressing against each other during rotation. Is used, it is possible to prevent the occurrence of galling with other members due to the axial thrust force generated at the time of rotation of the gear, thereby preventing an increase in load. (E03) Since a pair of helical gears is used as the gear meshing with the helical gear, mounting of the gear on the stud (gear support shaft) can be facilitated.

[Brief description of the drawings]

FIG. 1 is an overall explanatory diagram of an image forming apparatus and a sheet feeding member according to an embodiment of the present invention.

FIG. 2 is an enlarged explanatory view of a main part of a sheet feeding member of the image forming apparatus of the present embodiment.

FIG. 3 shows a state in which a sheet in a sheet cassette is transferred to a transfer area where a toner image formed on a photosensitive drum of the copying machine (image forming apparatus) shown in FIGS. FIG. 5 is a diagram illustrating a mechanism for transmitting a rotational force to a sheet conveying roll for taking out and conveying the sheet.

FIG. 4 is a detailed explanatory view of a main part shown in FIG. 3 and is a top view of a rotational force transmission mechanism D1.

FIG. 5 is an explanatory view of an assembling method of the rotational force transmission mechanism D1. FIG. 5A is a diagram illustrating a helical gear mounting stud arranged on both sides of a yama gear mounting stud, respectively. FIG. 5B is a view showing a state in which the helical gear is mounted, and FIG. 5B is a diagram illustrating a state in which the helical gear is mounted on the stud for mounting the helical gear after the helical gear of FIG. 5A is mounted so as to mesh with the helical gear. FIG. 5C is a view showing the situation, in which the helical gear of FIG. 5B is mounted, and then the helical gear is engaged with the helical gear on the helical gear mounting studs on both sides of the yamagear gear mounting stud. FIG. 5D shows how the helical gears G1 and G5 are mounted on the helical gear G after the helical gear of FIG. 5C is mounted.
It is explanatory drawing of the method of assembling so that 2 and G4 may be engaged.

FIG. 6 is a detailed explanatory view of a main part shown in FIG. 3 and is a top view of a rotational force transmission mechanism D2.

FIG. 7 is an explanatory view of an assembling method of the rotational force transmission mechanism D2, and FIG. 7A is a diagram illustrating a helical gear mounting stud arranged adjacent to a helical gear mounting stud. FIG. 7B is a view showing a state in which the tooth gear is mounted, and FIG.
7A is a view showing a state in which the helical gear is mounted on the stud for mounting the helical gear so as to mesh with the helical gear, and FIG. It is a figure which shows a mode that a helical gear is mounted on the helical gear mounting stud adjacent to the yamagear gear mounting stud so as to mesh with the yamagear gear.

8 is an explanatory view of a method of assembling the helical gears G6 and G9 so as to mesh with the helical gear G7 and the helical gear G8 after the helical gear of FIG. 7C is mounted.

FIG. 9 is an explanatory view of a rotational force transmission mechanism using a conventional gear, in a transfer area where a toner image formed on a photosensitive drum of a copying machine (image forming apparatus) is transferred to a recording sheet; FIG. 4 is a diagram illustrating a mechanism for transmitting a rotational force to a sheet transport roll for taking out and transporting a sheet in a paper feed cassette.

FIG. 10 is a view showing the torque transmitting mechanism (G6) shown in FIG. 9;
-G9) is a plan view of a case where a helical gear is used in place of the helical gear used for the gears of FIGS.

FIG. 11 is an explanatory diagram of a case where a mountain gear is mounted on each of two studs.

[Explanation of symbols]

D1, D2: rotational force transmission mechanism; G2a, G2b, G4a, G4b; G8a, G8b: a pair of helical gears; G3; G7: yama-tooth gear; G2 to G4; , 6c; 11a, 11b... Studs (gear mounting shaft).

Claims (2)

[Claims] 1. A pair of helical gears rotatably supported so as to be axially overlapped on the same axis and twisted in opposite directions so as to generate a thrust force in a direction of pressing against each other during rotation; A torque transmitting mechanism having a helical gear meshing with a helical gear. 2. The torque transmission according to claim 1, further comprising an idler gear train in which a pair of helical gears on the same shaft and a pair of helical gears meshing with the pair of helical gears are alternately meshed. mechanism.