Sending paper gifts

Abstract

A paper feed roller that makes it easy to determine the lifespan of the roller. The paper feed roller 10 includes: a shaft body 12; and an elastomer layer 14 formed on the outer peripheral surface of the shaft body 12. The outer diameter of the elastomer layer 14 is 10 mm or more and 50 mm or less. On the outer peripheral surface of the elastomer layer 14, grooves 16 extending axially are formed in a number of 1 or more and 8 or less in the circumferential direction. The grooves 16 are either grooves with a constant groove width W in the depth direction or grooves with a gradually decreasing groove width W in the depth direction. The groove width W of the grooves 16 is 0.2 mm or more and 1.0 mm or less, and the groove depth D of the grooves 16 is 0.2 mm or more and 1.0 mm or less.

Description

Technical Field

[0001] This invention relates to a paper feed roller preferred for use in electronic photo equipment such as copiers, printers, and fax machines that employ electronic photo methods. Background Technology

[0002] The paper feed roller is formed into a roller shape from an elastic material such as rubber. Paper is fed by the friction generated between the outer circumference of the roller and the paper. If too much paper is fed through the roller, poor paper feeding is likely to occur. If poor paper feeding becomes more frequent, the user will contact maintenance personnel. The maintenance personnel will then determine the lifespan (replacement period) of the paper feed roller. However, there are practical situations where users find it difficult to determine the lifespan (replacement period) of the paper feed roller.

[0003] To address the aforementioned issues, for example, Patent Document 1 proposes a paper feed roller with grooves on its surface, using the disappearance of these grooves due to wear as a benchmark for the roller's lifespan. Based on this, users can determine when to replace the roller when the grooves on its surface disappear.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 07-172614 Summary of the Invention The problem that the invention aims to solve However, the lifespan (replacement period) of a roller cannot be judged solely by the amount of wear on its surface. This is because, for example, if the coefficient of friction on the roller surface decreases due to the accumulation of paper dust and other debris from the paper, poor paper feeding can still occur even with minimal wear.

[0005] The problem to be solved by the present invention is to provide a paper feed roller that makes it easy to determine the lifespan of the roller.

[0006] means for solving problems The inventors of this invention conducted in-depth research and found that the amount of wear on the roller is not necessarily related to the roller's lifespan. Compared with the amount of wear on the roller, the amount of paper dust adhering to the roller surface is a more reliable indicator of the relationship between the roller's lifespan and the roller's lifespan. Furthermore, it is possible to set grooves of a specific shape on the roller surface and determine the roller's lifespan by observing the relationship between the grooves of a specific shape and the amount of paper dust accumulated in those grooves. This led to the completion of this invention.

[0007] That is, the paper feed roller according to the present invention is based on the following: The paper feed roller comprises: a shaft body; and an elastomer layer formed on the outer peripheral surface of the shaft body, the outer diameter of the elastomer layer being 10 mm or more and 50 mm or less, and grooves extending axially being formed in a number of 1 or more and 8 or less in the circumferential direction on the outer peripheral surface of the elastomer layer, the grooves being either grooves with a constant groove width along the depth direction or grooves with a gradually decreasing groove width along the depth direction, the groove width being 0.2 mm or more and 1.0 mm or less, and the groove depth being 0.2 mm or more and 1.0 mm or less.

[0008] The groove is particularly preferably a groove with a gradually decreasing width along the depth direction. The number of the grooves in the circumferential direction is preferably 2 or more and 6 or less. The surface roughness Sp, expressed as the maximum value of the height from the average surface of the bottom of the groove, is preferably 20 μm or more and 150 μm or less.

[0009] Invention Effects The paper feed roller according to the present invention comprises: a shaft body; and an elastomer layer formed on the outer peripheral surface of the shaft body, the outer diameter of the elastomer layer being 10 mm or more and 50 mm or less, and grooves extending axially being formed in a number of 1 or more and 8 or less in the circumferential direction on the outer peripheral surface of the elastomer layer, the grooves being either grooves with a constant groove width in the depth direction or grooves with a gradually decreasing groove width in the depth direction, the groove width being 0.2 mm or more and 1.0 mm or less, and the groove depth being 0.2 mm or more and 1.0 mm or less. Since the roller life can be determined based on the relationship between the grooves and the amount of paper dust accumulated in the grooves, the determination of the roller life becomes easy.

[0010] If the groove is a groove with a gradually decreasing width along the depth direction, it is a shape in which paper dust is easily retained. In addition, it is easy to see the shape in which paper dust is retained by visual inspection. Therefore, it is particularly easy to judge the life of the roller based on the relationship between the groove and the amount of paper dust accumulated in the groove.

[0011] Furthermore, if the number of grooves in the circumferential direction is 2 or more and 6 or less, it is particularly easy to judge the life of the roller based on the relationship between the grooves and the amount of paper dust accumulated in the grooves.

[0012] Furthermore, if the surface roughness Sp, expressed as the maximum height from the average surface of the bottom of the groove, is 20 μm or more and 150 μm or less, the effect of retaining paper dust in the groove is excellent, and the paper dust is less likely to move from the groove to other parts of the roll surface. In this way, the decrease in the coefficient of friction of the roll surface caused by paper dust is suppressed, thus improving the accuracy of judging the roll life by the retention of paper dust in the groove. Attached Figure Description

[0013] Figure 1 This is a schematic diagram (a) of the appearance of the paper feed roller according to one embodiment of the present invention and its AA-line cross-sectional view (b).

[0014] Figure 2 This is an enlarged cross-sectional view of the outer peripheral surface of the elastomer layer of the paper feed roller. Detailed Implementation

[0015] The paper feed roller involved in this invention will be described in detail. Figure 1 This is a schematic diagram (a) of the appearance of the paper feed roller according to one embodiment of the present invention and its AA-line cross-sectional view (b). Figure 2 This is an enlarged cross-sectional view of the outer peripheral surface of the elastomer layer of the paper feed roller.

[0016] One embodiment of the present invention includes a paper feed roller 10 comprising: a shaft 12; and an elastomer layer 14 formed on the outer peripheral surface of the shaft 12. The elastomer layer 14 is a layer (base layer) that forms the substrate of the paper feed roller 10. The elastomer layer 14 is a layer that appears on the surface of the paper feed roller 10.

[0017] The shaft 12 can be made of metal or resin, and can be solid or hollow (cylindrical). Examples of metal materials include iron, stainless steel, and aluminum. The elastomer layer 14 can also be bonded to the shaft 12 via an adhesive layer (primer layer). The adhesive and primer can also be made conductive as needed.

[0018] The elastomer layer 14 is formed in a roller shape on the outer peripheral surface of the shaft 12 from an elastic material. Grooves 16 extending axially are formed on the outer peripheral surface of the elastomer layer 14 in a circumferential direction at a number of 1 to 8. The grooves 16 have a specific shape, and the lifespan of the roller can be determined based on the relationship between the grooves 16 and the amount of paper dust accumulated in the grooves 16. The grooves 16 can be continuously formed from one end to the other along the axial direction on the outer peripheral surface of the elastomer layer 14, or they can be formed only in a portion of the axial direction. Furthermore, the paper dust referred to here includes waste, scraps, fibers, etc., discharged from the paper, as well as calcium carbonate, kaolin, etc., which are compounded in the paper. Paper dust is particularly prone to occur in paper produced overseas. Calcium carbonate and kaolin are amorphous, with a particle size of approximately 1~3 μm.

[0019] exist Figure 2 An example of the shape of the groove 16 is shown in the figure. Figure 2 This is a diagram showing a portion of the outer peripheral surface in the radial section of the elastomer layer 14. Figure 2 The cross-sectional shape of groove 16 in (a) is "ko" shaped, and it is a groove with a constant groove width W along the depth direction. Figure 2 The cross-sectional shape of groove 16 in (b) is "ko" shaped, and it is a groove with a constant groove width W along the depth direction. Figure 2 In groove 16 of (b), the bottom corner of groove 16 is rounded. Figure 2 The groove 16 in (c) has a V-shaped cross-section and a width W that gradually decreases along its depth. The bottom surface of the groove 16 is flat. Figure 2 In slot 16 of (c), it can also be as follows Figure 2 Like groove 16 in (b), the bottom corner of groove 16 is rounded.

[0020] like Figure 2 As shown, since the grooves 16 formed on the outer peripheral surface of the elastomer layer 14 are either grooves with a constant groove width W along the depth direction or grooves with a gradually decreasing groove width W along the depth direction, paper dust is easily retained. Furthermore, the presence of retained paper dust is easily visually assessed. Therefore, the lifespan of the roll can be easily determined based on the relationship between the grooves 16 and the amount of paper dust accumulated in the grooves 16. In particular, if the grooves 16 formed on the outer peripheral surface of the elastomer layer 14 are grooves with a gradually decreasing groove width along the depth direction, the lifespan of the roll is particularly easy to determine based on the ease of paper dust retention, visual ease of assessment, and the relationship between the grooves 16 and the amount of paper dust accumulated in the grooves 16.

[0021] The groove width W of groove 16 is 0.2 mm or more and 1.0 mm or less, and the groove depth D of groove 16 is 0.2 mm or more and 1.0 mm or less. If either the groove width W or the groove depth D is less than 0.2 mm, the capacity of groove 16 for retaining paper dust is too small. The groove will be full of paper dust before paper feeding defects occur, and the roller life cannot be judged based on the relationship between groove 16 and the amount of paper dust accumulated in groove 16. On the other hand, if either the groove width W or the groove depth D exceeds 1.0 mm, the capacity of groove 16 for retaining paper dust is too large. When many paper feeding defects occur, it is difficult to visually determine whether there is sufficient paper dust accumulation in groove 16, and the roller life cannot be judged based on the relationship between groove 16 and the amount of paper dust accumulated in groove 16. By ensuring that both the groove width W and the groove depth D are 0.2 mm or more and 1.0 mm or less, the roller life can be judged based on the relationship between groove 16 and the amount of paper dust accumulated in groove 16.

[0022] The groove width W of groove 16 is more preferably 0.3 mm or more, and even more preferably 0.4 mm or more. Furthermore, it is more preferably 0.9 mm or less, and even more preferably 0.8 mm or less. The groove depth D of groove 16 is more preferably 0.3 mm or more, and even more preferably 0.4 mm or more. Furthermore, it is more preferably 0.9 mm or less, and even more preferably 0.8 mm or less.

[0023] The grooves 16 are formed in a number of 1 to 8 or less in the circumferential direction. If the number of grooves 16 exceeds 8, the grooves 16 have a greater impact on the paper conveying performance, resulting in poor conveying performance. In particular, if the outer diameter φ of the elastomer layer 14 is small, the roller may bounce and wobble (generating strips) during rotation, making it impossible to convey paper. Moreover, from the viewpoint that it is particularly easy to judge the roller life based on the relationship between the grooves 16 and the amount of paper dust accumulated in the grooves 16, the number of grooves 16 is preferably 2 or more and 6 or less in the circumferential direction. When multiple grooves 16 are formed in the circumferential direction, the grooves 16 are preferably formed at equal intervals in a balanced position in the circumferential direction.

[0024] The bottom surface of the groove 16 preferably has a moderate roughness by forming protrusions as convex portions on the radially outer side or small concave portions as concave portions on the radially inner side. This effectively retains paper dust in the groove 16, preventing it from easily moving from the groove 16 to other parts of the roll surface. Thus, the decrease in the coefficient of friction of the roll surface due to paper dust is suppressed, thereby improving the accuracy of judging the roll's lifespan based on the amount of paper dust retained in the groove 16. The roughness of the bottom surface of the groove 16 can be expressed as a surface roughness Sp, which is the maximum value of the height from the average surface of the bottom surface of the groove 16. The surface roughness Sp of the bottom surface of the groove 16 is preferably 20 μm or more and 150 μm or less. More preferably, the surface roughness Sp of the bottom surface of the groove 16 is 30 μm or more, and even more preferably 50 μm or more. Furthermore, the surface roughness Sp of the bottom surface of the groove 16 is more preferably 120 μm or less, and even more preferably 100 μm or less.

[0025] The outer diameter φ of the elastomer layer 14 is 10 mm or more and 50 mm or less. If the outer diameter of the elastomer layer 14 is less than 10 mm, the amount of paper dust generated is small due to the small clamping force with the paper. Therefore, the amount of paper dust entering the groove 16 is less, and it is difficult to visually determine whether the groove 16 is sufficiently filled with paper dust when many paper feeding problems occur. The life of the roller cannot be judged based on the relationship between the groove 16 and the amount of paper dust accumulated in the groove 16. On the other hand, if the outer diameter of the elastomer layer 14 exceeds 50 mm, the amount of paper dust generated is large due to the large clamping force with the paper. Therefore, the amount of paper dust entering the groove 16 is greater, and the groove is already full of paper dust before paper feeding problems occur. The life of the roller cannot be judged based on the relationship between the groove 16 and the amount of paper dust accumulated in the groove 16. The outer diameter of the elastomer layer 14 is more preferably 15 mm or more, and more preferably 20 mm or more. In addition, the outer diameter of the elastomer layer 14 is more preferably 45 mm or less, and more preferably 40 mm or less.

[0026] From the viewpoint of clamping the elastomer layer to the paper, the JIS-A hardness of the elastomer layer 14 is preferably 25 degrees or more and 85 degrees or less. More preferably, it is 30 degrees or more and 80 degrees or less.

[0027] The elastomer layer 14 is composed of elastic materials such as rubber, elastomer, and resin. There are no particular limitations on the material as long as it is a rubber-like elastic material. For example, known materials such as polyurethane rubber, chlorohydrin rubber, silicone rubber, and EPDM can be used.

[0028] Various additives may also be added to the elastomer layer 14 as needed. Examples of additives include lubricants, vulcanization accelerators, anti-aging agents, light stabilizers, viscosity modifiers, processing aids, flame retardants, plasticizers, fillers, dispersants, defoamers, pigments, and release agents.

[0029] There is no particular limitation on the thickness of the elastomer layer 14; it can be set appropriately within the range of 2 to 25 mm.

[0030] The elastomer layer 14 can be formed by molding based on a molding die. For example, a tubular elastomer layer 14 can be formed by coaxially placing a core material in the hollow part of a roll forming die, injecting an uncrosslinked rubber composition, heating and curing (crosslinking), and then demolding. The molding die can be a die with protrusions of a shape corresponding to the groove 16 formed on its inner circumferential surface. The groove 16 of the elastomer layer 14 can be formed, for example, by mold transfer based on the molding die. The unevenness of the inner circumferential surface of the molding die can be formed by various unevenness forming methods such as electrical discharge machining, etching, shot peening, and grinding. The paper feed roller 10 can be formed by inserting a shaft 12 into the cylindrical elastomer layer 14.

[0031] The paper feed roller 10 configured as described above has grooves 16 formed on the outer peripheral surface of the elastomer layer 14 that extend axially and have a constant groove width W along the depth direction, or grooves with a gradually decreasing groove width W along the depth direction. Therefore, paper dust is easily retained, and the presence of retained paper dust is easily visually assessed. Furthermore, since the groove width W of the groove 16 is 0.2 mm or more and 1.0 mm or less, and the groove depth D of the groove 16 is 0.2 mm or more and 1.0 mm or less, the capacity of the groove 16 for retaining paper dust is appropriate, allowing the roller's lifespan to be determined based on the relationship between the groove 16 and the amount of paper dust accumulated in it. Moreover, since the grooves 16 are formed in a number of 1 or more and 8 or less along the circumferential direction of the outer peripheral surface of the elastomer layer 14, the grooves 16 have minimal impact on the paper's conveying performance, and the conveying performance does not deteriorate. Furthermore, since the outer diameter of the elastomer layer 14 is 10 mm or more and 50 mm or less, the clamping of the paper is appropriate, and the amount of paper dust entering the groove 16 is also appropriate. Therefore, the life of the roller can be determined based on the relationship between the groove 16 and the amount of paper dust accumulated in the groove 16. As described above, since the life of the roller can be determined based on the relationship between the groove 16 and the amount of paper dust accumulated in the groove 16, the determination of the roller's life becomes easy.

[0032] The embodiments of the present invention have been described above. However, the present invention is not limited to any of the above embodiments and various changes can be made without departing from the spirit of the present invention.

[0033] Example The present invention will now be described in detail using examples and comparative examples.

[0034] Using a cylindrical forming die with axially extending protrusions on its inner circumferential surface, an elastomer layer of a polyurethane rubber composition is formed on the outer circumference of a core material (φ6, made of SUS304). This results in a feed roller with predetermined grooves on the outer circumferential surface of the elastomer layer. Figure 2 As shown in (c), the groove shape is one in which the groove width gradually decreases along the depth direction. In the table, φ is the outer diameter of the elastomer layer, n is the number of grooves, W is the groove width, and D is the groove depth. The groove width W and groove depth D were measured by observing the radial cross-section of the elastomer layer of the fabricated paper feed roller.

[0035] Using the fabricated paper feed roller, printing was repeated until a paper feed defect occurred. At the point of defection, the radial cross-section of the elastomer layer of the paper feed roller was observed, and the amount of paper dust remaining in the slot was measured. In the table, numbers from 10 to 90 represent the volume of paper dust occupying the slot (fill rate). A fill rate exceeding 100% before the paper feed defect occurred was rated as "-". Furthermore, a fill rate of 50% to 100% at the point of defection was rated as "good" ("〇"), a fill rate exceeding 20% ​​to 50% was rated as "defective" ("△"), and a fill rate below 20% was rated as "defective" ("×"). The experimental results are shown in Tables 1 to 8 below.

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044] As shown in Tables 2, 3, 6, and 7, within the range of n=1~8, φ=10mm or more and φ=50mm or less, and with groove width W=0.2mm or more and 1.0mm or less, and groove depth D=0.2mm or more and 1.0mm or less, the filling rate of paper dust into the groove when paper feeding defects occur is 50% or more and 100% or less. When paper feeding defects occur, the presence of paper dust can be clearly confirmed visually, and the life of the roller can be judged based on the relationship between the groove and the amount of paper dust accumulated in the groove.

[0045] As shown in Table 1, if φ is 5mm, the clamping force between the elastomer layer and the paper is small. Therefore, even with various changes to the groove width W and groove depth D, the amount of paper dust entering the groove is small. The filling rate of paper dust into the groove when paper feeding defects occur is less than 50%, making it difficult to visually determine whether the groove is sufficiently filled with paper dust. Therefore, the roller life cannot be judged based on the relationship between the groove and the amount of paper dust accumulated in the groove. Furthermore, as shown in Table 4, if φ is 60mm, the clamping force between the elastomer layer and the paper is large. Therefore, even with various changes to the groove width W and groove depth D, the amount of paper dust entering the groove increases. The groove is already full of paper dust before paper feeding defects occur. The roller life cannot be judged based on the relationship between the groove and the amount of paper dust accumulated in the groove.

[0046] According to Table 5, when n=9 and φ is 5mm, the roller was observed to bounce and wobble during paper feeding, resulting in failure to feed paper (NG). Furthermore, according to Table 8, when n=9 and φ is 60mm, due to the large clamping force between the elastomer layer and the paper, even with various changes to the groove width W and groove depth D, the amount of paper dust entering the groove increases. The groove is already full of paper dust before paper feeding problems occur, making it impossible to judge the roller's lifespan based on the relationship between the groove and the amount of paper dust accumulated in it.

[0047] Furthermore, as shown in Tables 2, 3, 6, and 7, even if n=1~8, φ is 10mm or more and φ is 50mm or less, when the groove width W is 0.2mm or more and 1.0mm or less, and the groove depth D is 0.2mm or more and 1.0mm or less, if the filling rate exceeds 100% before the paper feeding defect occurs, or the filling rate of paper dust into the groove is less than 50% when the paper feeding defect occurs, the life of the roller cannot be judged based on the relationship between the groove and the amount of paper dust accumulated in the groove.

[0048] Furthermore, the above embodiments indicate that... Figure 2 The embodiment implemented using the groove shape shown in (c) is shown, but for Figure 2 (a) Figure 2 The same result was obtained for the embodiment with the groove shape shown in (b) in the figure.

[0049] The embodiments and examples of the present invention have been described above. However, the present invention is not limited to any of the above embodiments and examples, and various changes can be made without departing from the spirit of the present invention.

[0050] Explanation of reference numerals in the attached figures: 10: Paper feeding roller; 12: Shaft; 14: Elastomer layer; 16: trough; W: Slot width; D: Groove depth.

Claims

1. A paper feeding roller (10), wherein, The paper feed roller (10) comprises: Shaft (12); and An elastomer layer (14) is formed on the outer peripheral surface of the shaft (12). The outer diameter of the elastomer layer (14) is 10 mm or more and 50 mm or less. On the outer peripheral surface of the elastomer layer (14), grooves (16) extending axially are formed in a number of 1 to 8 in the circumferential direction. The groove (16) is a groove (16) with a constant groove width (W) along the depth direction. The groove width (W) of the groove (16) is 0.2 mm or more and 1.0 mm or less. The groove (16) has a groove depth (D) of 0.2 mm or more and 1.0 mm or less.

2. A paper feeding roller (10), wherein, The paper feed roller (10) comprises: Shaft (12); and An elastomer layer (14) is formed on the outer peripheral surface of the shaft (12). The outer diameter of the elastomer layer (14) is 10 mm or more and 50 mm or less. On the outer peripheral surface of the elastomer layer (14), grooves (16) extending axially are formed in a number of 1 to 8 in the circumferential direction. The groove (16) is a groove (16) with a gradually decreasing groove width (W) along the depth direction. The groove width (W) on the outer periphery of the groove (16) is 0.2 mm or more and 1.0 mm or less. The groove (16) has a groove depth (D) of 0.2 mm or more and 1.0 mm or less.

3. The paper feed roller (10) according to claim 1 or 2, wherein, The number of the grooves (16) in the circumferential direction is more than 2 and less than 6.

4. The paper feed roller (10) according to claim 1 or 2, wherein, The surface roughness Sp, expressed as the maximum height from the average surface of the bottom surface of the groove (16), is 20 μm or more and 150 μm or less.

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