Paper feed device for sheet recording device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention can be applied to a sheet recording device such as a printer such as a laser printer, a copying machine, a facsimile, a printing machine, etc., which records on a sheet such as paper or an envelope by printing, transfer, copying, printing, or the like. More specifically, the present invention relates to a paper feeding device that rotates a paper feeding roller to send a sheet to a recording unit of the sheet recording device main body in such a sheet recording device.

【0002】

[Conventional technology]

Conventionally, there is a paper feed device of this type having a configuration as shown in FIG. 7, for example. That is, the paper feed roller 2 and the reversing roller 3 are arranged vertically on the left side of the paper feed tray 1 in the paper feed direction, and the support arm 4 is rotatably held by the roller shaft 2a of the paper feed roller 2, and the support arm 4 is rotatably held. The tip portion 4a of 4 holds the feeding roller 5 via the roller shaft 5a. Further, the belt b is hung between the pulleys 6 and 6 held by the roller shaft 2a and the roller shaft 5a, respectively, and the rotation of the paper feed roller 2 is transmitted to the roller 5 via the belt b. Then, at the time of paper feeding, the support arm 4 is rotated around the roller shaft 2a to press the feeding roller 5 against the sheet S, and the feeding roller 5 is rotated to feed the sheet S. The reversing roller 3 was rotated and sent to a recording unit in the main body of the sheet recording device (not shown). Further, in this conventional paper feeding device, an opening 4b is opened in the tip portion 4a of the support arm 4, a roller shaft 5a is inserted into the opening 4b from the engaging groove 4c and engaged, and the feeding roller 5 is detachably attached. To do. Then, when it was time to replace the feed roller 5, the belt b was removed and then the feed roller 5 was removed from the support arm 4.

【0003】

In addition, as shown in FIG. 6, for example, a sheet guide plate 8 and a paper feed roller (not shown) and many other paper feed system parts are integrated between the left and right side plates 7 and 7 among other paper feed devices. In some cases, the paper feed unit 9 was detachably assembled to the sheet recording device main body (not shown), and the paper feed unit 9 was replaceable together with the paper feed unit 9.

【0004】

[Problems to be Solved by the Invention]

However, in the conventional paper feeding device shown in FIG. 7, even if only the feeding roller 5 can be easily replaced, it is not easy to replace the paper feeding roller 2 located on the back side in the paper feeding direction.

【0005】

On the other hand, in the conventional paper feed device shown in FIG. 6, when only the paper feed roller is to be replaced, the entire paper feed unit 9 is removed and other parts that do not need to be replaced are also replaced, resulting in high cost. There was a problem.

【0006】

Therefore, an object of the present invention is to make it possible to easily replace the paper feed roller without incurring a high cost.

【0007】

[Means for solving problems]

Therefore, the paper feed device 25 according to claim 1 can rotate the paper feed roller 26 that feeds the sheet S to the recording unit of the device main body 10 and the paper feed roller 26, as shown in the illustrated embodiment below. It has a bracket 53 that is detachably attached to the stay 42 in the apparatus main body 10 and a roller shaft 52 of the paper feed roller 26 that engages with and detaches from the drive shaft 45 when the bracket 53 is attached and detached. It is characterized by.

【0008】

In the invention according to claim 2, for example, as shown in the illustrated embodiment below, in the paper feed device 25 according to claim 1, a hook projection is provided on either one of the bracket 53 and the stay 42, and the hook projection is provided. A notch is provided on the other side. For example, the bracket 53 is provided with a hooking protrusion 53b, the stay 42 is provided with a notch 44, the hooking protrusion 53b is hooked on the notch 44, and the bracket 53 is detachably attached to the stay 42. It is characterized by that.

【0009】

The invention according to claim 3 is a leaf spring that holds the hooking projection 53b on the notch 44 in the paper feeding device 25 according to claim 2, as shown in the illustrated embodiment below. It is characterized in that an elastic member such as 64 is provided.

【0010】

According to the fourth aspect of the present invention, for example, as shown in the illustrated embodiment below, in the paper feeding device 25 according to the first aspect, one end 52a of the roller shaft 52 is abutted against one end 45a of the drive shaft 45. The drive shaft 45 and the roller shaft 52 are linearly connected to each other.

【0011】

The invention according to claim 5 covers, for example, a connecting portion between the drive shaft 45 and the roller shaft 52 in the paper feeding device 25 according to claim 4, as shown in the illustrated embodiment below. The connecting member 48 is provided, and the connecting member 48 is supported on the drive shaft 45 side.

【0012】

The invention according to claim 6 comprises, for example, as shown in the illustrated embodiment below, in the paper feed device 25 according to claim 1, a clutch is provided between the paper feed roller 26 and the roller shaft 52. It is characterized by that.

【0013】

[Action]

Then, in the invention according to claim 1, when the paper feed roller 26 is replaced, the bracket 53 is removed from the stay 42, and the roller shaft 52 of the paper feed roller 26 and the drive shaft 45 are disengaged.

【0014】

In the invention according to claim 2, at this time, the hook projection 53b is removed from the notch 44, and the bracket 53 is removed from the stay 42.

【0015】

In the invention according to claim 3, when the bracket 53 is attached to the stay 42, the elastic member holds the hooking projection 53b in the hooked state with respect to the notch 44.

【0016】

In the invention according to claim 4, when the roller shaft 52 of the paper feed roller 26 is connected to the drive shaft 45, one end 52a of the roller shaft 52 is abutted against one end 45a of the drive shaft 45.

【0017】

In the invention according to claim 5, at that time, the connecting portion between the roller shaft 52 and the drive shaft 45 is covered with a connecting member 48 supported on the drive shaft 45 side to maintain the connected state.

【0018】

In the invention according to claim 6, when a jam occurs, the clutch shuts off the rotation transmission from the roller shaft 52 to the paper feed roller 26.

【0019】

[Example]

Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 5 is a schematic diagram of the overall configuration of a laser printer including a paper feed device according to an embodiment of the present invention. What is indicated by reference numeral 10 in the figure is the main body of the apparatus. A belt-shaped photoconductor 11 is provided in the center of the apparatus main body 10. A charger 12, a developing device 13, a transfer device 14, and a cleaning device 15 are arranged around the photoconductor 11 in the order indicated by the arrows in the drawing. Then, the optical writer 16 is arranged below the charger 12 and the cleaner 15. Further, on the lower side of the optical writer 16, the paper feed cassettes 17 and 17 containing the sheets S are arranged one above the other.

【0020】

In addition, a manual paper feed tray 20 is provided on the front side of the apparatus main body 10 on the right side in the drawing, near the upper part. A paper discharge stack 21 is provided on the left back side, and a paper discharge stack 22 and a paper discharge stack 23 are provided on the upper side. A paper ejection roller 24 is arranged in the ejection unit 22.

【0021】

Then, the paper feed roller 26 provided in the paper feed device 25 of the present invention is appropriately selected and driven, and the sheet S in the paper feed cassette 17 is sent out in the direction of the arrow A. Then, the sheet S is conveyed to the upper side of the photoconductor 11 by the resist roller 27 at the timing. The photoconductor 11 is driven counterclockwise as indicated by the arrow, and at that time, the surface is uniformly charged by the charger 12 and irradiated with the laser beam L from the optical writer 16 to be static on the photoconductor 11. Form an electro-latent image. This latent image is visualized by toner as it passes through the developer 13. Then, this visible image is transferred by the transfer device 14 to the lower surface of the front surface of the sheet S which has been conveyed to the upper side of the photoconductor 11. After the image transfer, the sheet S is conveyed to the fixing device 28 to fix the visible image. On the other hand, the photoconductor 11 after the visible image transfer is cleaned by the cleaner 15. On the other hand, the recorded sheet S that has exited the fuser 28 is conveyed by the paper ejection roller 29, guided upward by the conveying guide 30, inverted, and sequentially conveyed through the conveying path 34 by the paper ejection rollers 31, 32, and 33. , The paper ejection direction is appropriately switched by the switching guide 35, and a part of the sheet S is once ejected to the manual paper feed tray 20 in the arrow B direction by the paper ejection rollers 36 and 37. Alternatively, the paper is discharged in the direction of arrow C by the paper discharge roller 24 through the transport path 38 in the discharge unit 22, and is stacked on the paper discharge stack unit 23. On the other hand, in order to perform double-sided recording, the sheet S ejected in the direction of arrow B reverses the paper ejection roller 37, switches back, and feeds it back to the photoconductor 11 through the transport path 39, and also on the upper surface of the back surface of the sheet S. Make a record. When the sheet S is, for example, thick paper, the paper ejection direction is switched by the switching guide 40, the sheets are ejected in the arrow D direction, and the sheets are stacked on the paper ejection stack portion 21.

【0022】

By the way, as shown in FIG. 1 in detail, the illustrated laser printer includes left and right side plates 41 and 41 in the apparatus main body 10, and a paper feeding device 25 is arranged between the left and right side plates 41 and 41. The paper feeding device 25 is provided on the flat plate-shaped stay 42. The stay 42 has mounting pieces 42a and 42b bent downward in the figure at both left and right ends thereof, and also has two holding pieces 42c and 42d downwards closer to the right mounting piece 42b. Further, as shown in FIG. 2, a positioning hole 43 and T-shaped notches 44 are formed on both sides of the positioning hole 43 near the left side mounting piece 42a. Then, the drive shaft 45 is inserted into the shaft hole 46 formed in the one-side holding piece 42c with a larger diameter, and penetrates the bearing 47 provided in the shaft hole (not shown) of the other-side holding piece 42d. Then, the drive shaft 45 is rotatably held by these holding pieces 42c and 42d. As shown by the dotted line, the drive shaft 45 has one end 45a formed into a half-moon shape in cross section, and one end 45a is fitted to the tubular connecting member 48. The connecting member 48 is attached to one end 45a with a screw 49. A drive transmission gear 50 is attached to the other end 45b of the drive shaft 45.

【0023】

Further, the paper feed roller unit 51 is arranged on the left side of FIG. 1 of the drive shaft 45. The paper feed roller unit 51 includes the paper feed roller 26, a roller shaft 52 of the paper feed roller 26, and a bracket 53 that holds the paper feed roller 26 via the roller shaft 52. As shown in FIG. 2, the paper feed roller 26 is provided with rubber rollers 55 and 56 on both sides of the hub 54. The hub 54 incorporates a one-way clutch (not shown) between the rubber rollers 55 and 56 and the roller shaft 52 inside. The roller shaft 52 has one end (right end in the drawing) 52a formed in a half-moon shape in cross section, and is held by the leg portion 53a of the U-shaped bracket 53 via the bearing 57. The bracket 53 is formed by cutting up the upper side of each leg portion 53a to provide a T-shaped hooking protrusion 53b, and forming a positioning convex portion 53c between the hooking protrusions 53b.

【0024】

Then, the paper feed roller unit 51 is assembled to the stay 42. In that case, the bracket 53 moves to the right after passing the hook projection 53b through the left opening 44a of the T-shaped notch 44 as indicated by the middle chain line in FIG. Then, the hooking protrusion 53b is hooked on the right opening 44b of the notch 44, and the positioning protrusion 53c is fitted into the positioning hole 43. At the same time, as shown in FIG. 1, one end 52a of the roller shaft 52 is abutted against one end 45a of the drive shaft 45, and both shafts 52 and 45 are linearly connected. Then, the connecting portion of both shafts 52 and 45 is covered with the connecting member 48 and tightened with the screw 49 to maintain the connected state of both shafts 52 and 45. On the other hand, the leaf spring (elastic member) 64 is hooked on the hooking protrusion 53b of the bracket 53. As shown in FIG. 2, the leaf spring 64 has an elongated hole 65 substantially in the center, and both sides of the elongated hole 65 are bent into a chevron shape to form a push-up portion 64a, and a hook hole is formed in the push-up portion 64a. 66 is open. Further, at the left end in the drawing, a handle portion 64b is provided by bending upward. As shown in FIG. 3, the hook hole 66 is formed in a trapezoidal shape gradually widening toward the right end thereof. Then, hold the handle portion 64b of the leaf spring 64, pass the hook protrusion 53b through the wide right end of the hook hole 66, and then slide the leaf spring 64 to the right as indicated by the arrow in the figure to push up the chevron shape. Move beyond 64a and hook the hooking protrusion 53b to both side edges 66a of the hooking hole 66. Then, as shown in FIG. 1, the hooking protrusion 53b is pushed up by the inclined portion of the pushing-up portion 64a, and the hooking protrusion 53b is held in the hooked state with respect to the notch 44 of the stay 42. Then, the paper feed roller unit 51 is pressed against the stay 42 and supported by the stay 42.

【0025】

Then, in addition to the paper feed roller unit 51 and the drive shaft 45, other paper feed parts such as the sheet guide member 70 as shown in FIG. 4 are also assembled to the stay 42 to form a unit, and paper feed is performed. Configure device 25. Then, as shown in FIG. 1, the paper feeding device 25 is arranged between the left and right side plates 41 and 41, and is screwed to the side plates 41 and 41 with the mounting pieces 42a and 42b of the stay 42. In that case, the right side plate 41 is provided with an escape hole (not shown), and the drive transmission gear 50 is arranged outside the right side plate 41 through the escape hole.

【0026】

In the above-described paper feed device 25, the paper feed roller 26 is rotated to feed out the sheet S in the paper feed cassette 17, guided by the sheet guide member 70, and sent out to the recording unit. When it is necessary to replace the paper feed roller 26 after feeding paper in this way, slide the leaf spring 64 to the left in FIG. 3 by holding the handle portion 64b, and the hook hole 66 and the hook protrusion While disengaging 53b, one end 52a of the roller shaft 52 shown in FIG. 1 is pulled out from the connecting member 48, whereby the paper feed roller unit 51 is removed from the stay 42. Then, replace it with a new paper feed roller unit. If the sheet S is jammed during paper feeding, the one-way clutch cuts off the rotation transmission from the roller shaft 52 to the paper feeding roller 26, and then the jam processing is performed.

【0027】

By the way, in the illustrated embodiment described above, the bracket 53 is provided with the hooking protrusion 53b, the stay 42 is provided with the notch 44, the hooking protrusion 53b is hooked on the notch 44, and the bracket 53 is attached to and detached from the stay 42. It is configured to be freely attached. However, on the contrary, it is also possible to provide a hooking protrusion on the stay, provide a notch on the other bracket, hook the hooking protrusion on the notch of the bracket, and attach the bracket to the stay detachably. It is possible.

【0028】

[Effect of the invention]

Therefore, according to the present invention, the paper feed roller is detachably attached to the stay via the bracket, and the roller shaft is detachably connected to the drive shaft. Since only the paper feed roller can be replaced without replacing unnecessary parts, only the paper feed roller can be easily replaced without incurring a high cost.

【0029】

According to the second aspect of the present invention, the bracket of the paper feed roller is detachably attached to the stay by engaging the notch and the hook protrusion, so that the paper feed roller can be replaced even more easily. be able to. Further, in the invention according to claim 3, the hooking state of the hooking protrusion with respect to the notch is held by the elastic member, and the hooking protrusion can be hooked and released by simply attaching and detaching the elastic member. You can do it with certainty.

【0030】

According to the fifth aspect of the present invention, the connecting member that holds the connected state between the roller shaft and the drive shaft of the paper feed roller is supported on the drive shaft side, and the paper feed roller does not need to be replaced when the paper feed roller is replaced. It is possible to reduce the number of parts.

【0031】

According to the sixth aspect of the present invention, a clutch is provided between the paper feed roller and the roller shaft thereof to facilitate the jam processing work.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram of the main part of the paper feed device which is an Example of this invention. [Figure 2]

It is an exploded perspective view of the paper feed device.

[Fig. 3]

It is a state explanatory drawing which shows the attachment state of the leaf spring in the paper feed device.

[Fig. 4]

It is a perspective view which shows the paper feed device upside down.

[Fig. 5]

It is an overall schematic block diagram which shows the internal mechanism of the laser printer provided with the paper feed device.

[Fig. 6]

It is a perspective view of the conventional paper feed device.

[Fig. 7]

It is a block diagram which shows the other conventional paper feed device.

[Explanation of symbols]

10 Device body 25 Paper feed device 26 Paper feed roller 42 stay 44 notch 45 drive shaft 45a One end of the drive shaft 48 Connecting member 52 Roller shaft 52a One end of roller shaft 53 bracket 53b hanging protrusion 64 Leaf spring (elastic member) S sheet