Mute type one-way clutch assembly and file scanning device using same

Abstract

The utility model provides a mute type one-way clutch assembly. The mute type one-way clutch assembly comprises a first shaft and a second shaft. The gear is fixed at the first end of the first shaft; and the ratchet wheel is used for coupling the first shaft to the second shaft in a unidirectional driving manner, so that the gear drives the second shaft to rotate through the first shaft and the ratchet wheel, and the second shaft is prevented from driving the first shaft and the gear to rotate. The utility model further provides a file scanning device using the mute type one-way clutch assembly.

Description

Technical Field

[0001] The utility model relates to a document scanning device and a silent one-way clutch assembly, in particular to a silent one-way clutch assembly of a document scanning device and a document scanning device using the same. Background Art

[0002] In traditional scanners, fax machines and office machines, a document scanning device feeds documents into the machine in sequence from a paper feed tray, and then the machine scans each document in turn to generate image signals. Since a feed gap must be generated between adjacent documents, a one-way clutch assembly must be provided in the document scanning device in the machine to create a feed gap between the adjacent first and second documents, thereby generating multi-page image signals with separated pages.

[0003] Figure 1 Shows a schematic diagram of a traditional one-way clutch assembly 300. As Figure 1 shown, the structure and use of the one-way clutch assembly 300 are similar to the structure of the US5,116,038 patent. Relevant details can be understood from the US5,116,038 patent and will not be elaborated here. The one-way clutch assembly 300 includes a rotating shaft 310, a connecting bushing 320, a torsion spring 330 and a gear 340. The torsion spring 330 sleeved on one end of the connecting bushing 320 and one end of the gear 340. The first end 311 of the rotating shaft 310 passes through the connecting bushing 320, the torsion spring 330 and the gear 340 in sequence. The second end 312 of the rotating shaft 310 is connected to a feed roller (not shown in the figure) for feeding documents. The gear 340 is driven to rotate, and then drives the rotating shaft 310 to rotate unidirectionally through the torsion spring 330 and the connecting bushing 320. That is, when the gear 340 rotates, the rotating shaft 310 and the feed roller can be driven to rotate to feed documents, while when the documents drive the feed roller and the rotating shaft 310 to rotate, the gear 340 will not be driven to rotate. Through such a design, a feed gap (paper separation gap) can be generated between two adjacent documents.

[0004] However, in the above design structure during operation, the torsion spring 330 will rub against the connecting bushing 320 to generate abnormal noise and reduce the service life of the entire one-way clutch assembly 300. In addition, the gradual frictional wear will make the document feeding gradually become unstable, thereby gradually affecting the quality of document scanning, and thus unable to meet the increasing demand of users for higher image quality. Moreover, the vibration caused by the rotating gear 340 will be directly transmitted to the rotating shaft 310, which will also affect the scanning quality. Summary of the Utility Model

[0005] Therefore, an object of the present utility model is to provide a silent one-way clutch assembly and a document scanning device using the same, which utilize a ratchet wheel provided between two shafts to achieve unidirectional power transmission between the two shafts, so as to reduce the transmission of vibration and reduce noise.

[0006] To achieve the above object, the present utility model provides a silent one-way clutch assembly for a document scanning device, comprising: a first shaft and a second shaft; a gear fixed to the first end of the first shaft; and a ratchet wheel that couples the first shaft to the second shaft in a one-way driving manner, such that the gear drives the second shaft to rotate through the first shaft and the ratchet wheel, and prevents the second shaft from driving the first shaft and the gear to rotate.

[0007] The present utility model further provides a document scanning device, comprising: a body; a one-way clutch assembly rotatably mounted on the body; a feeding roller connected to the second shaft and driven by the second shaft to rotate; a driving gear set for driving the gear, the first roller and the second roller to rotate; and a scanning module located between the first roller and the second roller, wherein the feeding roller sequentially feeds a document through the first roller, the scanning module and the second roller, and the scanning module performs an image capturing operation on the passing document.

[0008] Through the above embodiments, most of the parts of the one-way clutch assembly with self-lubricating characteristics can be manufactured using engineering plastics, so that the relative movement between these parts will not generate abnormal noises, absorb vibrations or cut off the transmission of vibrations, making the operation of the document scanning device quieter. In addition, the service life can be effectively increased and the cost can be reduced. Description of the Drawings

[0009] Figure 1 It is a schematic diagram of a traditional one-way clutch assembly.

[0010] Figure 2 It is a perspective view of a document scanning device according to a preferred embodiment of the present utility model.

[0011] Figure 3 It is Figure 2 a partial rear view of the document scanning device of

[0012] Figure 4 It is Figure 3 a partial rear view of the document scanning device of

[0013] Figure 5 It is Figure 4 a combined view of the one-way clutch assembly of

[0014] Figure 6 It is Figure 5 an exploded view of the one-way clutch assembly of

[0015] Figure 7 It is Figure 6 a partial exploded view of the one-way clutch assembly of

[0016] Figure 8 It is Figure 2 a schematic cross-sectional view of the internal components of the document scanning device of

[0017] Figure 9 Side view schematic diagram of a document scanning device Figure 2 for

[0018] Description of reference numerals:

[0019] C, gentle rise surface; D, document; F, steep drop surface;

[0020] 10, first shaft; 11, first end; 12, second end; 13, second ratchet part; 14, middle diameter part; 16, groove; 17, hole; 20, second shaft; 21, first end; 22, second end; 24, second claw part; 30, gear; 31, small diameter part; 40, ratchet; 43, first ratchet part; 44, first claw part; 50, bushing; 60, snap ring; 70, first flange bearing; 80, second flange bearing; 100, one-way clutch assembly; 200, document scanning device; 210, body; 220, feeding roller; 230, drive gear set; 231, 232, 233, 234, gears; 240, first roller; 240', roller; 250, second roller; 250', roller; 260, 260', scanning module; 300, one-way clutch assembly; 310, rotating shaft; 311, first end; 312, second end; 320, connecting bushing; 330, torsion spring; 340, gear. Detailed implementation manners

[0021] To make the above content of the present utility model more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the accompanying drawings, makes the following detailed description.

[0022] Figure 2 Stereogram of a document scanning device according to a preferred embodiment of the present utility model. Figure 3 Side view schematic diagram of a document scanning device Figure 2 for Figure 2 Partial rear view of the Figure 3 As shown in

[0023] Figure 4 Side view schematic diagram of a document scanning device Figure 3 for Figure 5 Partial rear view of the Figure 4 Combined view of a one-way clutch assembly Figure 6 Exploded view of a one-way clutch assembly Figure 5 for Figure 7 Partial exploded view of a one-way clutch assembly Figure 6 As shown inFigures 2 to 7 As shown, the silent one-way clutch assembly 100 of the document scanning device 200 includes a first shaft 10, a second shaft 20, a gear 30, and a ratchet 40. The first shaft 10, the second shaft 20, and the ratchet 40 are coaxially arranged and have outer peripheral surfaces with substantially the same outer diameter, so that not much space will be wasted when placing the combined inventory. The gear 30 is fixed to the first end 11 of the first shaft 10. The ratchet 40 couples the first shaft 10 to the second shaft 20 in a one-way driving manner, enabling the gear 30 to drive the second shaft 20 to rotate through the first shaft 10 and the ratchet 40, and preventing the second shaft 20 from driving the first shaft 10 and the gear 30 to rotate. In one embodiment, the first shaft 10 can drive the second shaft 20 to rotate through the ratchet 40, but the second shaft 20 cannot drive the first shaft 10 to rotate through the ratchet 40. The feeding roller 220 is connected to the second shaft 20 and is driven by the second shaft 20 to rotate.

[0024] Through the above one-way clutch assembly 100, in addition to using the ratchet 40 to provide the function of a one-way clutch to avoid the noise generated when using a torsion spring, the vibration generated during the rotation of the gear 30 can be separated by the ratchet 40, preventing the vibration from being transmitted from the first shaft 10 to the second shaft 20. Moreover, the first shaft 10, the second shaft 20, and the ratchet 40 can be made of engineering plastics, which have self-lubricating properties, can reduce friction, reduce noise and vibration, increase service life, and reduce costs. In the operation test, the general standard test is 100,000 paper feedings. Using the one-way clutch assembly of the present utility model, the service life can reach 500,000 paper feedings. Compared with Figure 1 the structure, the cost of the one-way clutch assembly of the present utility model can be reduced by about 50%.

[0025] Optionally, the one-way clutch assembly 100 may further include a bushing 50, a snap ring 60, a first flange bearing 70, and a second flange bearing 80. The first shaft 10 passes through the small-diameter portion 31 of the gear 30, and the small-diameter portion 31 passes through the bushing 50, enabling the bushing 50 to rotatably fix the gear 30 to the body 210. Since the small-diameter portion 31 is between the small-diameter portion (near the first end 11) of the first shaft 10 and the bushing 50, compared with the case of directly positioning the small-diameter portion of the first shaft 10 by using the bushing 50, positioning the first shaft 10 by using the bushing 50 in cooperation with the small-diameter portion 31 can effectively utilize the parts and achieve a more stable effect. In addition, the snap ring 60 is snapped into the groove 16 at the first end 11 of the first shaft 10 to limit the axial movement of the gear 30. The first flange bearing 70 and the second flange bearing 80 are installed on the body 210. The middle-diameter portion 14 of the first shaft 10 passes through the first flange bearing 70, the second end 22 of the second shaft 20 passes through the second flange bearing 80, and the first flange bearing 70 and the second flange bearing 80 limit the axial movement of the first shaft 10 and the second shaft 20.

[0026] In addition, the first end 21 of the second shaft 20 is sleeved with the second end 12 of the first shaft 10 and is relatively rotatable. In one embodiment, the first end 21 of the second shaft 20 is inserted into the hole 17 of the second end 12 of the first shaft 10, can rotate relative to each other, and maintains axial stability. The ratchet 40 is rotatably disposed at the second end 12 of the first shaft 10 and the first end 21 of the second shaft 20, or rather, the ratchet 40 is rotatably disposed at the sleeved joint of the second end 12 and the first end 21. To achieve the effect of one-way clutch, the first ratchet portion 43 of the ratchet 40 is rotatably sleeved with the second ratchet portion 13 of the first shaft 10 to couple the first shaft 10 to the second shaft 20 in a one-way driving manner. Each of the first ratchet portion 43 and the second ratchet portion 13 includes a connected gentle rise surface C and a steep drop surface F. The power transmission is achieved by using the steep drop surface F, and the power transmission is disconnected by using the gentle rise surface C.

[0027] On the other hand, the first pawl portion 44 of the ratchet 40 is rotatably sleeved with the second pawl portion 24 of the second shaft 20 to provide a buffer interval for the second shaft 20 to rotate the ratchet 40. The buffer interval can also be used to control the paper separation gap of general-sized documents (such as A4 or Letter-sized documents), and it also prevents the dynamic instability caused by the coupling and decoupling of the first ratchet portion 43 and the second ratchet portion 13 from being immediately transmitted to the second shaft 20. Moreover, it can buffer the starting feeding time point of the next document. In this embodiment, each of the first pawl portion 44 and the second pawl portion 24 has two pawls.

[0028] Figure 8 For Figure 2 the schematic cross-sectional view of the internal components of the document scanning device. Figure 9 For Figure 2 the schematic side view of the document scanning device. As Figure 8 And Figure 9 shown, the document scanning device 200 further includes a drive gear set 230, a first roller 240, a second roller 250, and scanning modules 260 and 260' (a single scanning module is also applicable). The drive gear set 230 includes gears 231, 232, 233, and 234. The drive gear set 230 is used to drive the gear 30, the first roller 240, and the second roller 250 to rotate. The first roller 240 directly or indirectly drives the roller 240' to rotate, and the second roller 250 directly or indirectly drives the roller 250' to rotate.

[0029] The scanning modules 260 and 260' are located between the first roller 240 and the second roller 250. The feeding roller 220 feeds the document D sequentially through the first roller 240, the scanning modules 260 and 260', and the second roller 250. The scanning modules 260 and 260' perform an image capturing operation on the passing document D, that is, use a Charge-Coupled Device (CCD) image sensor or a Contact Image Sensor (CIS) to capture the image of the document D.

[0030] In one embodiment, a motor (not shown in the figure) drives the gear 231, the gear 231 drives the gears 232 and 233, the gear 232 drives the gear 234, and the gear 234 drives the gear 30. The gear 233 drives the first roller 240 and the second roller 250 to rotate, and the gear 30 drives the feeding roller 220 to rotate. When the motor rotates and the ratchet 40 couples the power transmission, the designed first tangential speed of the first roller 240 and the second roller 250 driving the document D is greater than the second tangential speed of the feeding roller 220 driving the document D. In the early stage when the document D is fed, when the document D is fed by the feeding roller 220 and has not contacted the first roller 240 yet, the ratchet 40 is coupled with the first shaft 10, and the first tangential speed is greater than the second tangential speed of the feeding roller 220. On the other hand, in the later stage when the document D is fed out, when the document D contacts the first roller 240, the ratchet 40 is decoupled from the first shaft 10 (the power transmission is cut off), and the first tangential speed of the first roller 240 and the second roller 250 is equal to the second tangential speed of the feeding roller 220, so that the document D will not be pulled and damaged. When the document D leaves the feeding roller 220 and is only fed by the first roller 240 and the second roller 250, another document (not shown in the figure) may have already contacted the feeding roller 220, and the first tangential speed of the first roller 240 and the second roller 250 is greater than the second tangential speed of the feeding roller 220, which can also create a paper separation gap between adjacent documents.

[0031] Through the one-way clutch assembly of the above embodiment, most of the parts with self-lubricating characteristics (except for the snap ring) can be manufactured using engineering plastics, so that the relative movement between these parts will not generate abnormal noises, absorb vibrations or cut off the transmission of vibrations, making the operation of the document scanning device quieter. In addition, the service life can be effectively increased and the cost can be reduced.

[0032] The specific embodiments proposed in the detailed description of the preferred embodiment are only used to conveniently illustrate the technical content of the present invention, rather than narrowly limiting the present invention to the above embodiments. Without exceeding the spirit and the scope of the patent application of the present invention, various changes and implementations belong to the scope of the present invention.

Claims

1. A silent one-way clutch assembly, characterized in that: Include: The first axis and the second axis; a gear fixed to the first end of the first shaft; and The ratchet couples the first shaft to the second shaft in a one-way driving manner, so that the gear drives the second shaft to rotate through the first shaft and the ratchet, and prevents the second shaft from driving the first shaft and the gear to rotate.

2. The silent one-way clutch assembly according to claim 1, characterized in that: Also includes: A bushing, wherein the small diameter portion of the gear passes through the bushing, so that the bushing can rotatably fix the gear to the body of the document scanning device.

3. The silent one-way clutch assembly according to claim 1, characterized in that: Also includes: A retaining ring is engaged in the groove of the first end of the first shaft to limit the axial movement of the gear.

4. The silent one-way clutch assembly according to claim 1, characterized in that: Also includes: The first flange bearing and the second flange bearing are installed on the body of the document scanning device, wherein the first axis passes through the first flange bearing, the second axis passes through the second flange bearing, and the first flange bearing and the second flange bearing limit the axial movement of the first axis and the second axis.

5. The silent one-way clutch assembly according to claim 1, characterized in that: The first end of the second shaft is sleeved with the second end of the first shaft and can rotate relatively, and the ratchet is rotatably arranged on the second end of the first shaft and the first end of the second shaft.

6. The silent one-way clutch assembly according to claim 5, characterized in that: The first ratchet portion of the ratchet wheel is rotatably sleeved with the second ratchet portion of the first shaft to couple the first shaft to the second shaft in a one-way driving manner.

7. The silent one-way clutch assembly according to claim 6, characterized in that: The first claw portion of the ratchet wheel is rotatably sleeved with the second claw portion of the second shaft to provide a buffer interval for the second shaft to rotate the ratchet wheel.

8. The silent one-way clutch assembly according to claim 5, characterized in that: The first end of the second shaft is inserted into the hole of the second end of the first shaft.

9. A document scanning device, characterized in that: Include: Body; The silent one-way clutch assembly according to claim 1 is rotatably mounted on the body; a feed roller connected to the second shaft and driven to rotate by the second shaft; A driving gear set, used for driving the gear, the first roller and the second roller to rotate; and The scanning module is located between the first roller and the second roller, wherein the feeding roller feeds the document through the first roller, the scanning module and the second roller in sequence, and the scanning module performs an image capture operation on the document passing through.

10. The document scanning device according to claim 9, characterized in that: in: When the document is fed by the feed roller and has not yet contacted the first roller, the ratchet is coupled to the first shaft, and a first tangential velocity of the first roller and the second roller is greater than a second tangential velocity of the feed roller; and When the document contacts the first roller, the ratchet is decoupled from the first shaft, and the first tangential velocity of the first roller and the second roller is equal to the second tangential velocity of the feed roller.

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