JP3716968B2 - Manufacturing method of sheet conveying roller in image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a sheet conveying roller for conveying a sheet such as printing paper after it is printed in an image forming apparatus such as a printer.
[0002]
[Prior art]
An image forming apparatus such as a printer includes a sheet conveying roller for discharging a sheet on which an image is formed. An ink jet printer provided with this sheet conveying roller is disclosed in Japanese Patent Laid-Open No. 10-120234 by the same applicant as the present application. FIG. 8 is a side view of an essential part of an ink jet printer provided with the sheet conveying roller.
[0003]
In the figure, 40 is a sheet supply roller, 41 is a separation pad, and the sheets S for printing are separated and sent out one by one. Reference numeral 42 denotes a platen roller, 42A denotes a driving roller thereof, and 42B denotes a driven roller. The platen roller 42 supplies the sent sheet S to the printing unit at a predetermined constant speed. A print head 43 is attached to the carriage 44. The carriage 44 is attached to the carriage guide shaft 45 and is slidable in the axial direction. The print head 43 is scanned in the axial direction. Reference numeral 46 denotes a defining member that defines a gap with the print head 43, and the sheet S is printed by the print head 43 while passing through the gap. 47 is an ink tank.
[0004]
48 is a sheet conveying roller pair for paper discharge, 49 is a driving roller, and 50 is a driven roller. The surface of the drive roller 49 is made of a hard rubber material and is formed in a rod shape. The driven roller 50 is a member related to the present application, and a ring-shaped tooth portion 50A made of a metal material and in which star-shaped teeth are arranged and a roller body 50B made of a synthetic resin material are integrally formed. Then, one or a plurality of units are slid onto a roller shaft 51 made of a contact spring, and a large number are arranged in the lateral direction of the sheet S so as to face the driving roller 49. The printed sheet S is conveyed while being sandwiched between the driving roller 49 and the driven roller 50 and discharged to the outside. The follower roller 50 has a sharp tip to prevent the sheet S from being damaged by the teeth in order to pinch and press the sheet S securely, but the tip has an arc shape.
[0005]
[Problems to be solved by the invention]
However, the driven roller has a metal tooth part and a roller body made of a synthetic resin material formed integrally, so that the structure becomes complicated and different types of manufacturing processes must be combined, so that the manufacturing cost is low. There was a problem of becoming higher.
[0006]
In order to solve the above-described problems, the present invention provides a method for manufacturing a sheet conveying roller that can be manufactured at low cost by integrally forming a driven roller of a sheet conveying roller for paper discharge. With the goal.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, in the roller shape build-up step, the peripheral portion of the roller and the peripheral portion of the shaft hole on the outer periphery of the blank made of a metal plate are crushed from both sides by forging, and the main portion of the roller. In the tooth root thickness forming process in the latter stage of the roller shape building process, the tooth equivalent part of the roller is crushed from both sides by forging, and the thickness shape of the tooth valley corresponding part is formed. In the shaft hole punching process in the latter stage of the roller shape build-up process, the shaft mounting hole is formed by punching, and in the tooth profile punching process in the latter stage of the shaft hole punching process, a star tooth shape is formed by punching, and the tooth profile punching process In the preliminary step of tooth profile formation at the subsequent stage, the tooth tip and its corresponding portion are crushed from one side by forging to form the thickness shape of the portion near the tooth tip. In the addendum portion forming step in the later stage of the tooth crests forming preliminary step, the tooth tip portion addendum being crushed from the one side is formed by forging.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
[0009]
FIG. 1 is a view showing a state where a blank shape is removed in a manufacturing process of a sheet transport driven roller for paper discharge as an embodiment of the present invention. (A) of the same figure is the top view, (b) is sectional drawing of a product part.
[0010]
The sheet conveying driven roller is made of soft stainless steel as a material that is easy to process and does not corrode. In this case, for example, a hoop material having a thickness slightly exceeding 1 mm is used. In the figure, reference numeral 10 denotes a hoop material made of a stainless steel plate, and the intermediate products shown in the following drawings are sequentially processed and formed by passing through each process. 20A is a blank corresponding to the outer shape of the roller, and is formed by being punched from the hoop material 10 in the initial step. Reference numeral 30 denotes a work connecting portion that connects the blank 20 </ b> A to the hoop material 10. In the following drawings, the illustration of the pilot hole or the escape hole for preventing the closing is omitted.
[0011]
2A and 2B are views showing a halfway product formed by the roller shape build-up process of the present invention. FIG. 2A is a plan view and FIG. 2B is a cross-sectional view of a product portion. In the figure, 20B is a semi-finished product obtained by this process. In the blank 20A shown in FIG. 1, the roller peripheral portion 21A and the central shaft hole peripheral portion 21B on the outer periphery thereof are crushed from both sides by cold forging (the same applies in the subsequent steps), and as a result, the roller body The equivalent portion 21C is built up, and the thickness of the main portion equivalent portion 21C is formed to be less than 2 mm.
[0012]
FIG. 3 is a view showing a halfway product formed by the tooth root thickness forming step of the present invention, in which (a) is a plan view and (b) is a cross-sectional view of the product portion. In the figure, 20C is a semi-finished product obtained by this process. This process is executed at the latter stage of the roller shape build-up process shown in FIG. 2, and as shown in FIG. 2, the former peripheral equivalent portion (tooth equivalent portion) 21A is crushed from both sides by forging, and the tooth valley equivalent portion. At the same time, the main body equivalent portion 21C of the previous roller is crushed from both sides by forging to form the main body equivalent thickness shape 22C. The thickness is set to a little less than 2 mm (a value smaller than the main body equivalent portion 21C).
[0013]
FIG. 4 is a view showing a halfway product formed by the shaft hole punching process of the present invention. FIG. 4A is a plan view thereof, and FIG. 4B is a sectional view of a product portion. In the figure, 20D is a semi-finished product obtained by this process. This step is executed at the latter stage of the roller body thickness forming step shown in FIG. 3, and as shown in the drawing, a shaft hole 23 for inserting the attachment shaft is formed by punching.
[0014]
FIG. 5 is a view showing a halfway product formed by the tooth profile removing process of the present invention. FIG. 5A is a plan view thereof, and FIG. 5B is a sectional view of a product portion. In the figure, 20E is a semi-finished product obtained by this process. This step is executed at a stage subsequent to the shaft hole punching step shown in FIG. 4, and as shown in the drawing, a star-shaped tooth profile 24 is formed by punching. The tooth profile 24 has an arcuate tip portion.
[0015]
FIGS. 6A and 6B are views showing a halfway product formed by the tooth profile ridge formation preliminary process of the present invention. FIG. 6A is a plan view and FIG. 6B is a cross-sectional view of a product portion. In the same figure, 20F is a semi-finished product by this process. The process is performed after the tooth extraction step shown in FIG. 5, and as shown in FIG. 5, the tooth tip and the vicinity thereof are stepped from one side by forging and are crushed to form a portion near the tooth tip. A thickness shape 25 is formed. The thickness is set to a little less than 0.1 mm.
[0016]
FIG. 7 is a view showing a halfway product formed by the tooth tip portion forming step of the present invention, in which (a) is a plan view and (b) is a cross-sectional view of the product portion. In the figure, 20G is a semi-finished product produced by this process. This step is executed in the subsequent stage of the tooth profile ridge formation preliminary step shown in FIG. 6, and as shown in FIG. 6, the tooth tip portion is crushed from one side by forging to form the tooth tip 26 as a finished product. The external dimension of this finished product is set to less than 10 mm. In addition, the hardness of this roller increases by being forged in each process. The semi-finished product 20G is cut off from the connecting portion 30 and completed as a sheet conveying roller.
[0017]
The sheet conveying roller thus manufactured is integrally formed of a metal material and manufactured with forging, so the shape of the tooth tip and the wall thickness of the shaft hole are set appropriately. It is possible to obtain a high-quality sheet conveying roller at low cost.
[0018]
【The invention's effect】
According to the present invention, in the roller shape build-up process, the roller main body equivalent part in the blank made of the metal plate is built up by forging, and in the tooth root thickness forming process, the thickness of the tooth valley part in the roller In the shaft hole punching process, the shaft mounting center hole is formed by punching, in the tooth profile punching process, a star tooth shape is formed by punching, and in the tooth profile crest formation preliminary process, the tooth shape is formed by forging. The thickness shape of the tip vicinity is formed by forging, and the tooth tip is formed by forging in the tooth tip forming process, so the sheet conveying roller is integrally formed of metal and manufactured with forging Therefore, the shape of the teeth and the thickness of the shaft hole can be appropriately set, so that a high-quality sheet conveying roller can be obtained at low cost.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a state in which a blank shape is removed in a manufacturing process of a sheet conveying driven roller for paper discharge as an embodiment of the present invention.
FIG. 2 is a view showing a halfway product formed by the roller shape build-up process of the present invention.
FIG. 3 is a view showing a halfway product formed by a tooth root thickness forming step of the present invention.
FIG. 4 is a diagram showing a halfway product formed by the shaft hole punching process of the present invention.
FIG. 5 is a view showing a halfway product formed by the tooth profile removing process of the present invention.
FIG. 6 is a diagram showing a halfway product formed by a tooth profile ridge formation preliminary process according to the present invention.
FIG. 7 is a view showing a halfway product formed by a tooth tip forming step of the present invention.
FIG. 8 is a side view of an essential part of an ink jet printer including a sheet conveying roller according to the present invention.
[Explanation of symbols]
10 Hoop material 20A Blank 20B Intermediate product 20C by roller shape build-up process Intermediate product 20D by tooth root thickness forming process Intermediate product 20E by axial hole punching process Intermediate product 20F by tooth profile extraction process Intermediate product 20G by tooth profile extraction process Intermediate product 23 by shaft forming process Shaft hole 24 Tooth profile 26 Tooth tip

Claims (1)

In a method for manufacturing a sheet transport roller for transporting a discharged sheet in an image forming apparatus,
Roller shape build-up process of crushing from the both sides by forging the peripheral part of the roller and the part corresponding to the periphery of the shaft hole from a blank made of a metal plate,
A tooth root thickness forming step of forming the thickness shape of the tooth valley corresponding portion by crushing the tooth corresponding portion of the roller from both sides by forging in the latter stage of the roller shape build-up step;
A shaft hole punching step for forming a shaft mounting hole by punching in the latter stage of the roller shape build-up step,
Tooth profile punching process for forming a star-shaped tooth profile by punching in the subsequent stage of the shaft hole punching process;
Tooth profile ridge formation preliminary step that crushes one side of the tooth tip and its vicinity corresponding portion by forging in the latter stage of the tooth profile extraction step to the thickness of the tooth profile vicinity portion;
A tooth tip portion forming step of forming a tooth tip by crushing the tooth tip portion from one side by forging at a subsequent stage of the tooth profile peak forming preliminary step,
A method of manufacturing a sheet conveying roller in an image forming apparatus.

Images