Intermediate transfer printing unit and image forming device

Abstract

The utility model provides an intermediate transfer printing unit and an image forming device. The intermediate transfer printing unit comprises a frame, an intermediate transfer printing belt, a plurality of photosensitive drums, a plurality of transfer printing rollers and sealing assemblies, wherein the sealing assemblies are arranged on the two sides of the intermediate transfer printing belt in the width direction respectively; the sealing assembly includes a first sealing sheet that seals a gap formed by an edge of the intermediate transfer belt and the frame, and a second sealing sheet that seals an opening on the frame. According to the intermediate transfer printing unit and the image forming device, toner is prevented from entering the interior of the intermediate transfer printing belt, the toner is prevented from polluting the primary transfer printing roller, and the image quality is guaranteed.

Description

Technical Field

[0001] The present invention relates to an intermediate transfer unit provided with a sealing assembly and an image forming device. Background Art

[0002] A conventional image forming apparatus includes a photosensitive drum as an image carrier, a charging device, an exposure device, a developing device, and a transfer device. The toner images of each color (yellow, magenta, cyan, and black) formed on the circumferential surface of each photosensitive drum are sequentially transferred to an intermediate transfer belt by superposition. The intermediate transfer belt is formed by an endless belt driven to rotate, and after the color image is synthesized on it, the color image is transferred to a recording medium. Finally, it is compressed and heated by a fixing device to perform a fixing process.

[0003] However, during the transfer process, the toner is easy to scatter inside the image forming device, especially through the gap between the transfer frame and the intermediate transfer belt to the inner surface of the intermediate transfer belt, and adhere to the primary transfer roller. Common primary transfer rollers are steel rollers or ion-conductive rubber rollers. If the toner adheres to the primary transfer roller of this type of material, the resistance value of the primary transfer roller will increase locally, resulting in undesirable problems such as whitening of the image. Summary of the invention

[0004] In order to solve the above technical problems existing in the prior art, the utility model provides an intermediate transfer unit and an image forming device provided with a sealing component, which prevents the toner from scattering into the interior of the intermediate transfer unit and ensures the image quality.

[0005] The purpose of the utility model is achieved through the following solutions:

[0006] An intermediate transfer unit, comprising:

[0007] A frame rotatably supports the intermediate transfer belt, the tensioning member, and the plurality of transfer rollers, wherein the frame is provided with a plurality of openings;

[0008] The intermediate transfer belt has an endless shape and is used to receive the toner images from the plurality of photosensitive drums;

[0009] The tensioning member tensions the intermediate transfer belt;

[0010] The plurality of transfer rollers are arranged opposite to the plurality of photosensitive drums via the intermediate transfer belt, and transfer the toner images from the plurality of photosensitive drums to the peripheral surface of the intermediate transfer belt;

[0011] The sealing components are respectively arranged on both sides of the intermediate transfer belt in the width direction, and are characterized in that:

[0012] The sealing assembly includes a first sealing sheet that seals a gap formed by an edge of the intermediate transfer belt and the frame, and a second sealing sheet that seals the plurality of openings on the frame.

[0013] Further, the first sealing sheet is in sliding contact with the intermediate transfer belt so that a gap between an edge of the intermediate transfer belt and the frame can be fully sealed.

[0014] Furthermore, the first sealing sheet includes a first shielding member, and the first shielding member is disposed between the plurality of transfer rollers and the plurality of photosensitive drums.

[0015] Furthermore, a avoidance groove is provided on the first shielding member at a position opposite to the plurality of photosensitive drums to prevent the first shielding member and the plurality of photosensitive drums from contacting and causing wear or abnormal noise.

[0016] Furthermore, the opening penetrates the frame, and the second sealing sheet is provided on the outer side of the frame to seal the outer side of the opening to prevent the toner from entering the inner peripheral side of the intermediate transfer belt through the opening exposed by the frame.

[0017] Furthermore, the sealing assembly further includes a third sealing sheet, the tension member has a portion exposed outside the frame, and the third sealing sheet is used to seal the portion to prevent the toner from entering the inner peripheral side of the intermediate transfer belt through the tension member.

[0018] Furthermore, at least one end of the first sealing sheet and / or the second sealing sheet is fixed to the frame, so that the sealing assembly is not likely to fall off from the frame.

[0019] Furthermore, to facilitate production and assembly, at least one end of the first sealing sheet and / or the second sealing sheet is adhered to the frame by means of double-sided tape.

[0020] Furthermore, the sealing component is made of PET, TPU or a combination of TPU and PET. The TPU material has a certain flexibility, so it can fully seal the gap without damaging the intermediate transfer belt and the photosensitive drum. The PET material has the characteristics of high hardness and good toughness, which makes it easy to fix the sealing component to the frame.

[0021] Furthermore, the material of the first shielding member is a combination of TPU and PET, and the PET part is adhered to the surface of the TPU part by double-sided tape, which can play a certain supporting role.

[0022] Furthermore, the plurality of transfer rollers are composed of a steel roller and an elastic rubber layer or a sponge layer covering the outer periphery of the steel roller, and the elastic rubber layer or the sponge layer is made of an electronically conductive material. The electronically conductive material transfer roller has a strong stability, and even if there is scattered toner or dust attached to its surface, the influence of its resistance fluctuation is small.

[0023] The utility model has the advantages of blocking the toner from entering the interior of the intermediate transfer belt, preventing the toner from contaminating the primary transfer roller, and ensuring the image quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a front view of the internal structure of the image forming device in the utility model;

[0025] Figure 2 It is a front view of the intermediate transfer unit and its peripheral components of the image forming device in the utility model;

[0026] Figure 3 It is a structural schematic diagram of the intermediate transfer unit of the utility model without the sealing component installed;

[0027] Figure 4 It is a structural schematic diagram of the intermediate transfer unit after the sealing assembly is installed in the utility model;

[0028] Figure 5 It is a top view of the intermediate transfer unit in the utility model.

[0029] Figure 6 It is a bottom view of the intermediate transfer unit in the utility model.

[0030] Figure 7 yes Figure 6 A partial enlarged view of .

[0031] Figure 8 It is a front view of the intermediate transfer unit in the utility model.

[0032] Fig. 9 It is a stereoscopic diagram of the cooperation between the second shielding member and a plurality of photosensitive drums and a plurality of primary transfer rollers in the utility model. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0035] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0036] (First embodiment)

[0037] Figure 1 1 is a schematic structural diagram of an image forming device 1, which is a multifunction machine having multiple functions such as a copy function, a print function, a scan function, and a fax function. In order to better describe the image forming device 1, an XYZ three-dimensional rectangular coordinate system is established, wherein the X-axis direction is the length direction of the image forming device, the Y-axis direction is the width direction of the image forming device, the Z-axis direction is the height direction of the image forming device, the +Z-axis direction is also the "up" direction of the image forming device, and the -Z-axis direction is the "down" direction of the image forming device.

[0038] The image forming apparatus 1 includes, from top to bottom, a paper discharge unit 12, a toner cartridge storage unit 13, an image forming unit, and a paper storage unit 14. The image forming apparatus 1 is provided with a paper conveying unit 18 extending from the paper storage unit 14 at the bottom to the paper discharge unit 12 at the top.

[0039] The image forming unit includes an image forming unit 13Bk for black (Bk), an image forming unit 13Y for yellow (Y), an image forming unit 13C for cyan (C), and an image forming unit 13M for magenta (M). These image forming units 13Bk, 13Y, 13C, and 13M respectively include photosensitive drums 16Bk, 16Y, 16C, and 16M as image carriers, charging rollers for charging the surfaces of the photosensitive drums 16Bk, etc., and developing devices 161 for forming colorant images on the photosensitive drums 16Bk, etc.

[0040] The image forming unit further includes an intermediate transfer unit 15. Figure 2 and Figure 3As shown, the intermediate transfer unit 15 is composed of a frame 158, an intermediate transfer belt 151, a driving roller 152, a guide roller 153, a plurality of primary transfer rollers 154, and a tensioning component. Among them, the guide roller 153 is used to assist the transfer belt 151 in keeping it centered. The tensioning component includes a tensioning roller 155 and a spring 1551. The tensioning roller 155 is pressed by the spring 1551 through the frame 158 in the direction of tensioning the intermediate transfer belt 151, so as to maintain a specified tension of the intermediate transfer belt 151.

[0041] The frame 158 supports the intermediate transfer belt 151, the driving roller 152, the guide roller 153, the primary transfer roller 154, and the tension roller 155. The frame 158 is provided with a plurality of openings 1581, and the respective rotation axes of the driving roller 152, the guide roller 153, the primary transfer roller 154, and the tension roller 155 are rotatably supported in the openings 1581.

[0042] The intermediate transfer belt 151 is stretched between the driving roller 152 and the tension roller 155, and is driven by the driving roller 152 while in contact with the peripheral surfaces of the photosensitive drums 16Bk, 16Y, 16C, and 16M, and circulates synchronously with the photosensitive drums 16Bk and the like, and transfers the toner image on the outer peripheral surface. In addition, the intermediate transfer belt 151 is supported from the inner peripheral side by the tension roller 155 disposed near the guide roller 153.

[0043] The primary transfer roller 154 is disposed opposite to the plurality of photosensitive drums with the intermediate transfer belt 151 interposed therebetween, and transfers the toner images from the plurality of photosensitive drums 16Bk, 16Y, 16C, and 16M to the peripheral surface of the intermediate transfer belt 151. The primary transfer roller 154 is an example of a transfer roller in the scope of the claims.

[0044] In order to effectively control the problem of the increase of the resistance value of the primary transfer roller after the toner adheres to the surface of the primary transfer roller 154, the primary transfer roller is composed of a steel roller and an electronic conductive rubber layer coated on the periphery of the steel roller. The rubber base material of the electronic conductive rubber layer is NBR (nitrile rubber) and ECO (chloroether rubber). In order to give conductivity to the formed rubber layer, a conductive agent can be added to the rubber elastic layer forming material, and the conductive agent includes electronic conductive agents such as carbon-based conductive materials. For example, carbon black compounds. The resistance value of the electronic conductive material transfer roller is stable relative to environmental changes. When the resistance of the primary transfer roller 154 is high, even if there is scattered toner or dust attached to its surface, it is less affected by resistance fluctuations. Therefore, the primary transfer roller 154 with an electronic conductive rubber layer has long-term reliability.

[0045] The periphery of the photosensitive drum 16Bk is uniformly charged (charging process), and the surface of the charged photosensitive drum 16Bk is irradiated with laser light 17 based on image data to form a latent image (exposure process). The latent image formed on the surface of the photosensitive drum 16Bk is visualized by the toner supplied from the developing roller constituting the developing device 161 (developing process), and the toner image formed by visualization is transferred to the intermediate transfer belt 151 by the primary transfer roller 154.

[0046] The toner images of the respective colors (black, yellow, cyan, and magenta) transferred onto the intermediate transfer belt 151 are superimposed on the intermediate transfer belt 151 while adjusting the transfer timing, thereby forming a color toner image.

[0047] The secondary transfer roller 156 transfers the color toner image formed on the surface of the intermediate transfer belt 151 onto the recording paper conveyed from the paper storage unit 14 at the nip section 157 where the secondary transfer roller 156 and the driving roller 152 nip the intermediate transfer belt 151 .

[0048] Furthermore, a sealing assembly 159 is provided on the frame 158 . Figure 4 FIG. 1 is a diagram showing the intermediate transfer unit 15 after the seal assembly 159 is installed. Since the scattered toner can enter the inner peripheral side of the intermediate transfer belt 151 from the plurality of openings 1581, the gap between the edge of the intermediate transfer belt 151 and the frame 158, respectively. Figures 4 to 6 As shown, when viewed from the Z-axis direction, the sealing assemblies 159 are respectively arranged on both sides of the width of the intermediate transfer belt 151.

[0049] like Figures 4 to 8 As shown, the sealing assembly 159 includes a first sealing sheet 1591 and a second sealing sheet 1592, which are respectively used to seal the gap between the opening 1581, the edge of the intermediate transfer belt 151 and the frame 158. Since the intermediate transfer belt 151 is circulated during the transfer process, the toner may still enter the inner peripheral side of the intermediate transfer belt 151 from between the intermediate transfer belt 151 and the second sealing sheet 1592. In order to fully seal the gap between the edge of the intermediate transfer belt 151 and the frame 158, the first sealing sheet 1591 is set to extend from the frame 158 to the surface of the intermediate transfer belt 151 and exceed the edge of the intermediate transfer belt 151. The first sealing sheet 1591 having the portion exceeding the edge of the intermediate transfer belt 151 will slide in contact with the intermediate transfer belt 151.

[0050] Further, when viewed from the Y-axis direction, the first sealing sheet 1591 includes a first shielding member 1591a, which is located at the downstream side 151a of the running direction of the intermediate transfer belt 151 (i.e., the lower side of the outer periphery of the transfer belt in the +Z-axis direction), and the first shielding member 1591a is provided between the plurality of primary transfer rollers 154 and the photosensitive drum 16Bk, etc., to prevent the toner from entering the inner periphery of the intermediate transfer belt 151 from between the primary transfer rollers 154 and the photosensitive drum 16Bk, etc. The first sealing sheet 1591 also includes a second shielding member 1591b, which is located at the upstream side 151b of the running direction of the intermediate transfer belt 151 (i.e., the upper side of the outer periphery of the transfer belt in the +Z-axis direction). The second sealing sheet 1592 is provided on the outer side of the frame 158, and is located between the first shielding member 1591a and the second shielding member 1591b. The combination of the first sealing sheet 1591 and the second sealing sheet 1592 can largely prevent toner from entering the interior of the intermediate transfer unit 15 and contaminating the primary transfer roller 154 .

[0051] Furthermore, the sealing assembly 159 further includes a third sealing sheet 1593. Figure 3 and Figure 8 As shown, the tensioning component includes a tensioning roller 155 and a spring 1551 supported by a frame 158. The frame 158 is provided with a recessed portion for accommodating the spring 1551 of the tensioning component, and the rotation axis of the tensioning roller 155 extending to both ends in the length direction thereof is rotatably supported by the frame 158. The spring 1551 is exposed on the outer side of the frame 158, and the scattered toner easily enters the inner peripheral side of the intermediate transfer belt 151 through the spring 1551 and the recessed portion. Therefore, a third sealing sheet 1593 is provided to close the recessed portion accommodating the spring 1551 to achieve a better sealing effect.

[0052] The following further describes the fixing position and fixing method of the first sealing sheet 1591 and / or the second sealing sheet 1592. At least one end of the first sealing sheet 1591 and / or the second sealing sheet 1592 is fixed to the frame 158. In order to better implement this solution, one end (long end) of the first sealing sheet 1591 is fixed to the end of the frame 158 in the Y-axis direction, and the two ends (two long ends corresponding to each other) of the second sealing sheet 1592 are fixed to the edge of the outer side surface (Z-axis direction) of the frame 158, so that the first sealing sheet 1591 and / or the second sealing sheet 1592 are not easy to fall off from the frame 158.

[0053] Further, to facilitate assembly, at least one end of the first sealing sheet 1591 and / or the second sealing sheet 1592 is attached to the frame 158 by double-sided tape. During production and assembly, the double-sided tape can be attached to the ends of the first sealing sheet 1591 and the second sealing sheet 1592 first, and then the first sealing sheet 1591 and the second sealing sheet 1592 attached with the double-sided tape are attached to the frame 158. Of course, in some other embodiments, the first sealing sheet 1591 and the second sealing sheet 1592 can also be fixed to the frame 158 by screws or the like, which is not limited here.

[0054] Furthermore, the material of the sealing component 159 can be TPU or PET. Specifically, it depends on the position where the sealing component 159 is set. In this embodiment, the second shielding member 1591b and the third sealing sheet 1593 are preferably made of TPU material, and the second sealing sheet 1592 is preferably made of PET material. The TPU material is flexible, and when the first sealing sheet 1591 contacts the intermediate transfer belt 151, it will not cause damage to it, and can achieve a good sealing effect. The characteristics of PET are high hardness and good toughness, which makes it easy to directly adhere the second sealing sheet 1592 to the frame 158, avoiding deformation of the second sealing sheet 1592 due to improper operation during production and assembly.

[0055] (Second embodiment)

[0056] like Fig. 9 As shown, the intermediate transfer unit 15 also includes a swing arm. The swing arm is rotatably sleeved on the shaft end of the primary transfer roller 154, and when it contacts the photosensitive drum isolation sleeve 162 (directly or indirectly), it maintains a predetermined gap between the photosensitive drum 16Bk and the primary transfer roller 154. When printing is in black and white mode, the swing arm 1541 and the three primary transfer rollers 154 are moved away (retracted) from the corresponding photosensitive drums (16Y, 16C, 16M) by a driving source not shown. When printing is in color mode, the swing arm 1541 is rotated by a driving source not shown until it contacts the photosensitive drum isolation sleeve 162 and presses each other, that is, the three primary transfer rollers 154 approach the position of the corresponding photosensitive drums (16Y, 16C, 16M). At this time, the lower end of the swing arm 1541 is approximately located on a straight line connecting the circumferential surfaces of the photosensitive drums (16Bk, 16Y, 16C, 16M).

[0057] Since the first shielding member 1591a is disposed between the plurality of primary transfer rollers 154 and the photosensitive drum 16Bk, etc., if the first shielding member 1591a and the photosensitive drum 16Bk, etc. are in contact for a long time, abnormal noise may be generated during the transfer process, and the surface coating of the photosensitive drum 16Bk, etc. may be worn, thereby affecting the printing quality. Figure 7 and Fig. 9As shown, an avoidance groove a4 is provided at the position where the first shielding member 1591a and the photosensitive drum 16Bk are opposite, and the end of the avoidance groove a4 is a sharp angle with an obtuse angle, which can reduce the contact area between the photosensitive drum 16Bk and the first shielding member 1591a.

[0058] Furthermore, the material of the sealing component 159 can also be a combination of TPU and PET. In this embodiment, the first shielding member 1591a is preferably a combination of PET and TPU. The TPU material can prevent the first shielding member 1591a from scratching the intermediate transfer belt 151, but because the first shielding member 1591a is provided with a plurality of avoidance grooves a4, the flexibility of the TPU material is strong, which will make the first shielding member 1591a lack support as a whole, and it is not convenient to stick it to the frame 158. Therefore, the material of the first shielding member 1591a is selected as a combination of PET and TPU, and PET can play a certain supporting role. However, the material of the sealing component 159 is not limited to the above-mentioned selection form, and other suitable materials can also be selected.

[0059] Next, the structure of the first shielding member 1591a is further described. Figure 7 As shown, the material of the first part a1 and the second part a2 of the first shielding member 1591a is PET, and the material of the third part a3 is TPU. The first part a1 is adhered to the surface of the third part a3 by double-sided tape. In order to better play a supporting role, the first part a1 has a certain thickness. The second part a2 is located between the photosensitive drum isolation sleeve 162 and the swing arm 1541 to prevent the toner from entering the inner peripheral side of the intermediate transfer belt 151 from the gap between the photosensitive drum isolation sleeve 162 and the swing arm 1541. Therefore, the thickness of the second part a2 is less than the thickness of the first part a1. Specifically, the thickness of the second part a2 is less than 0.05 mm. If the thickness is set to exceed this range, the gap between the primary transfer roller 154 and the photosensitive drum 16Bk will increase, affecting the transfer quality.

[0060] Furthermore, one end of the second part a2 is pasted on the frame 158, and the other end is pasted on the third part a3, which also serves to connect the third part a3 and the frame 158, so that the first shielding member 1591a is not easy to fall off from the frame 158.

[0061] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the protection scope of the claims of the utility model.

Claims

1. An intermediate transfer unit, comprising: A frame, wherein a plurality of openings are provided on the frame; A tensioning member rotatably disposed on the frame; an intermediate transfer belt, which is tensioned by the tensioning member and is used to receive toner images from a plurality of photosensitive drums; A plurality of transfer rollers are provided on the frame, are arranged opposite to the plurality of photosensitive drums via the intermediate transfer belt, and transfer the toner images from the plurality of photosensitive drums to the peripheral surface of the intermediate transfer belt; The sealing components are respectively arranged on both sides of the intermediate transfer belt in the width direction, and are characterized in that: The sealing assembly includes a first sealing sheet that seals a gap formed by an edge of the intermediate transfer belt and the frame, and a second sealing sheet that seals the plurality of openings on the frame.

2. The intermediate transfer unit according to claim 1, characterized in that: The first sealing sheet is in sliding contact with the intermediate transfer belt.

3. The intermediate transfer unit according to claim 1, characterized in that: The first sealing sheet includes a first shielding member disposed between the plurality of transfer rollers and the plurality of photosensitive drums.

4. The intermediate transfer unit according to claim 3, characterized in that: The first shielding member is provided with an escape groove at a position opposite to the plurality of photosensitive drums.

5. The intermediate transfer unit according to claim 1, characterized in that: The opening penetrates the frame, and the second sealing sheet is provided on an outer side surface of the frame to seal the outside of the opening.

6. The intermediate transfer unit according to claim 1, characterized in that: The sealing assembly further includes a third sealing sheet, the tension member has a portion exposed outside the frame, and the third sealing sheet is used to seal the portion.

7. The intermediate transfer unit according to any one of claims 1 to 5, characterized in that: At least one end of the first sealing sheet and / or the second sealing sheet is fixed on the frame.

8. The intermediate transfer unit according to claim 7, characterized in that: At least one end of the sealing component is adhered to the frame by double-sided adhesive.

9. The intermediate transfer unit according to claim 1 or 6, characterized in that: The sealing component is made of TPU, PET or a combination of TPU and PET.

10. The intermediate transfer unit according to claim 1, wherein: The multiple transfer rollers are composed of a steel roller and an elastic rubber layer or a sponge layer coated on the outer circumference of the steel roller, and the elastic rubber layer or the sponge layer is made of electronic conductive materials.

11. An image forming device, characterized in that: The invention comprises the intermediate transfer unit according to any one of claims 1 to 10, and forms an image by transferring a toner image formed by the intermediate transfer unit to a recording paper.

12. An intermediate transfer unit, comprising: A frame, wherein a plurality of openings are provided on the frame; A tensioning member rotatably disposed on the frame; an intermediate transfer belt, which is tensioned by the tensioning member and is used to receive toner images from a plurality of photosensitive drums; A plurality of transfer rollers are provided on the frame, are arranged opposite to the plurality of photosensitive drums via the intermediate transfer belt, and transfer the toner images from the plurality of photosensitive drums to the peripheral surface of the intermediate transfer belt; The first shielding member is disposed between the plurality of transfer rollers and the plurality of photosensitive drums, and is characterized in that the material of the first shielding member is a combination of TPU and PET.

Images