Fixing structure for imaging equipment and imaging equipment

Abstract

The invention relates to a fixing structure for imaging equipment and the imaging equipment. The fixing structure comprises a heating roller; a pressure roller; the first gear is fixedly mounted at the end part of the heating roller and is coaxial with the heating roller; the transmission wheel is annular, a circle of tooth part is arranged on the outer circumferential wall of the transmission wheel in the circumferential direction of the transmission wheel, the tooth part is directly or indirectly meshed with the first gear, a circle of transmission teeth are arranged on the inner circumferential wall of the transmission wheel in the circumferential direction of the transmission wheel, and the two wall faces, sequentially arranged in the circumferential direction of the transmission wheel, of each transmission tooth are the first face and the second face correspondingly; the one-way transmission part is mounted at the end part of the pressurizing roller; the transmission claw can be movably mounted on the one-way transmission part, and the transmission claw can be in a state that the transmission claw can abut against the first surface of any transmission tooth so that the transmission wheel and the one-way transmission part can be relatively fixed in the circumferential direction to be in a synchronous rotation state; the transmission claw can abut against the second face of any transmission tooth so that the transmission wheel can be separated from the one-way transmission piece. And the elastic piece acts on the transmission claw, so that the transmission claw keeps the tendency of abutting against the first surface, and the paper is prevented from slipping.

Description

Technical Field

[0001] The present invention relates to the technical field of imaging devices, and in particular to a fixing structure for an imaging device and the imaging device. Background Art

[0002] At present, imaging devices such as printers, copiers, fax machines, and multifunction printers have been widely used in people's lives and work.

[0003] Imaging devices feature a fusing mechanism that heats and pressurizes paper, thereby fixing toner to the paper. The fusing mechanism includes a tightly fitted heating roller and a pressure roller. The heating roller contains a heat source that heats the heating roller. To achieve optimal fusing, the heating roller and pressure roller are in pressure contact, forming a nip. After transfer, the paper enters the nip, receiving both heat and pressure, resulting in optimal fusing.

[0004] For example, the "Fixing Opening and Closing Device" disclosed in the Chinese utility model patent with patent application number CN202021463185.7 (publication number CN212623596U) includes a bracket, a heating roller, a pressure roller, a support arm, an elastic member, and a rocker arm. The pressure roller is axially parallel to the heating roller. The first end of the support arm is rotatably connected to the bracket, and the second end is connected to the end of the pressure roller. The elastic member is provided on the bracket and connected to the support arm, and is used to keep the pressure roller moving toward the heating roller to form a trend of fixing pressure. The rocker arm is rotatably connected to the bracket, and the first end is a rotating free end and the second end is linked to the support arm. When the second end of the rocker arm presses against the support arm, the pressure roller overcomes the elastic force of the elastic member and moves away from the heating roller.

[0005] However, the hardness and surface sleeve of the pressure roller have strict requirements. During use, changes in the surface friction coefficient of the pressure roller and NIP caused by surface wear and high-temperature aging will cause paper slippage. In addition, paper with a smooth surface may slip and print abnormally during the printing process. Summary of the Invention

[0006] The first technical problem to be solved by the present invention is to provide a fixing structure for an imaging device that prevents paper from slipping when passing through a pressure roller, in view of the current state of the prior art.

[0007] The second technical problem to be solved by the present invention is to provide an imaging device using the above-mentioned fixing structure in view of the current status of the existing technology.

[0008] The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: a fixing structure for an imaging device, comprising

[0009] A heating roller extending in a left-right direction and rotatable around its axis;

[0010] A pressure roller extends in a left-right direction and can rotate around its axis. The pressure roller is parallel to the heating roller, and a nip area for the paper to pass through is formed between the pressure roller and the heating roller.

[0011] It is characterized by also including

[0012] A first gear is fixedly mounted on the end of the heating roller and the two are coaxial;

[0013] A transmission wheel is annular in shape, and a tooth portion is provided on an outer peripheral wall of the transmission wheel along its circumference, the tooth portion is directly or indirectly engaged with the first gear, the number of teeth of the first gear is smaller than the number of teeth of the tooth portion, and a transmission tooth portion is provided on an inner peripheral wall of the transmission wheel along its circumference, and two wall surfaces of each transmission tooth are sequentially arranged along the circumference of the transmission wheel, namely a first surface and a second surface;

[0014] A one-way transmission member is mounted on the end of the pressure roller and the two are relatively fixed in the circumferential direction, and the one-way transmission member is located in the annular area surrounded by the transmission wheels;

[0015] a transmission pawl movably mounted on the one-way transmission member, the transmission pawl being capable of being placed in a state of pressing against a first surface of any transmission tooth to fix the transmission wheel and the one-way transmission member relative to each other in the circumferential direction for synchronous rotation, and the transmission pawl being capable of being placed in a state of pressing against a second surface of any transmission tooth to disengage the transmission wheel and the one-way transmission member;

[0016] The elastic member acts on the transmission claw, so that the transmission claw maintains a tendency to resist the first surface.

[0017] The transmission pawl can be configured in a variety of ways. Preferably, one end of the pawl is rotatably mounted on the one-way transmission member, with the pawl's rotational axis parallel to the one-way transmission member's rotational axis. The other end of the pawl can abut against the transmission teeth. This rotatable configuration allows for a compact structure with the one-way transmission member, minimizes space, and provides excellent compatibility with the transmission teeth.

[0018] In order to make the transmission claw cooperate well with the transmission teeth in different states, the arrangement direction of the first surface and the second surface of the transmission tooth is defined as the clockwise direction of the transmission wheel, and the one-way transmission member rotates relative to the transmission wheel in the counterclockwise direction. The first surface of the transmission tooth is a surface perpendicular to the peripheral wall surface of the transmission wheel, and the second surface is an inclined surface inclined toward the one-way transmission member in the counterclockwise direction of the transmission wheel.

[0019] Preferably, the one-way transmission member is provided with a receiving groove, which is open on one side facing the transmission tooth. An axial hole is provided on one wall of the receiving groove, and one end of the transmission pawl is rotatably mounted in the axial hole via a rotating shaft. The other wall of the receiving groove can abut against the transmission pawl as a stop surface. The stop surface is designed to prevent the transmission pawl from rotating too far and being unable to return to its original position.

[0020] In the above scheme, the first gear and the tooth portion are transmitted through the second gear. A second gear coaxial with the first gear is fixedly provided on the first gear. The second gear is directly engaged with the tooth portion. The number of teeth of the first gear is smaller than that of the second gear, and the number of teeth of the second gear is the same as that of the tooth portion.

[0021] Preferably, there are at least two transmission claws, which are arranged at intervals along the circumference of the one-way transmission member to improve the positioning effect of the transmission claw on the one-way transmission member and enable it to cooperate well with the transmission wheel.

[0022] To achieve circumferential fixation between the pressure roller and the one-way transmission member, the pressure roller includes a central shaft and a sleeve sleeved over the central shaft. One end of the central shaft extends through the sleeve, and this end has a non-circular cross-section. The one-way transmission member has a socket for receiving the end of the central shaft, and this socket also has a non-circular cross-section. This simplifies assembly of the pressure roller and the one-way transmission member and ensures circumferential fixation between them.

[0023] The technical solution adopted by the present invention to solve the above-mentioned second technical problem is: an imaging device, characterized in that it includes the above-mentioned fixing structure.

[0024] Compared with the prior art, the advantages of the present invention are as follows: the present invention provides a transmission wheel, a one-way transmission member, a transmission tooth, etc., so that the heating roller is driven by the first gear to rotate, and the first gear drives the transmission wheel through the second gear;

[0025] During the rotation of the heating roller, the paper and the pressure roller are in contact with each other, the pressure roller rotates, and the paper passes through the nip zone. When the pressure roller is synchronized with the paper speed, the number of teeth of the first gear and the number of teeth of the tooth portion are different, and the rotation speed of the transmission wheel is lower than the rotation speed of the one-way transmission member. Since the first and second surfaces of the transmission teeth are arranged along the clockwise direction of the transmission wheel, the one-way transmission member rotates counterclockwise relative to the transmission wheel. Since the rotation speed of the one-way transmission member is higher than the rotation speed of the transmission wheel, the transmission claw contacts the second surface of the transmission teeth. At this time, the one-way transmission member and the transmission wheel are in a relatively independent rotation state, and the transmission wheel does not provide power to the pressure roller.

[0026] When the speed of the pressure roller and the paper are not synchronized, the rotation speed of the one-way transmission member decreases, and the rotation speed of the transmission wheel is greater than the rotation speed of the one-way transmission member. At this time, the transmission claw and the first surface of the transmission tooth are against each other, so that the transmission wheel and the one-way transmission member rotate synchronously, providing power for the pressure roller and reducing the friction required for the paper to drive the pressure roller, so as to prevent the paper from slipping and printing abnormalities. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A partial structural diagram of an embodiment of the present invention;

[0028] Figure 2 for Figure 1 A schematic diagram of the structure in another direction;

[0029] Figure 3 for Figure 2 A magnified view of point A;

[0030] Figure 4 for Figure 3 A schematic diagram of the structure of the transmission wheel, one-way transmission member, transmission claw, etc.;

[0031] Figure 5 for Figure 4 Schematic diagram of the decomposition;

[0032] Figure 6 for Figure 1 A cross-sectional view without the heating roller, the first gear, and the second gear. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described in detail below in conjunction with the embodiments of the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be understood that, in the description of the patent of the present invention, unless otherwise specified, "plurality" means two or more, and the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "top", "bottom", "front", "back", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the patent of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the patent of the present invention.

[0035] In the description of this patent, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integral connection; they can be mechanical connection or adhesive connection; and they can be directly connected or indirectly connected through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in this patent.

[0036] The imaging device may be a printer, a copier, etc., and the imaging device includes a fixing structure.

[0037] like Figures 1 to 6 As shown, the fixing structure of this preferred embodiment includes a heating roller 1 and a pressure roller 2. Both the heating roller 1 and the pressure roller 2 extend in the left-right direction and are rotatable about their axes. The pressure roller 2 is parallel to the heating roller 1, and a nip is formed between the two rollers for paper to pass through. This is prior art and will not be further described here.

[0038] The fixing structure further includes a first gear 11 , a transmission wheel 3 , a one-way transmission member 4 , a transmission claw 41 and an elastic member 42 .

[0039] The first gear 11 is fixedly mounted on the end of the heating roller 1 and is coaxial with the first gear 11. The first gear 11 is connected to a driving mechanism to rotate the heating roller 1. The driving mechanism can adopt existing technology. For example, the driving mechanism is a motor, and the output end of the motor is equipped with a driving gear that meshes with the first gear 11. When the motor is operating, the driving gear drives the first gear 11 to rotate, thereby driving the heating roller 1 to rotate. The pressure roller 2 and the heating roller 1 are in contact with each other, so that they can also rotate about their axes.

[0040] The transmission wheel 3 is annular in shape, with a circumferentially arranged toothed portion 31 formed on its outer peripheral wall. The toothed portion 31 directly or indirectly meshes with the first gear 11. The number of teeth on the first gear 11 is smaller than that on the toothed portion 31. In this embodiment, the first gear 11 and the toothed portion 31 are driven by a second gear 12. A second gear 12 is also fixedly mounted coaxially with the first gear 11 and directly meshes with the toothed portion 31. The number of teeth on the first gear 11 is smaller than that on the second gear 12, and the number of teeth on the second gear 12 is the same as that on the toothed portion 31.

[0041] A circle of transmission teeth 32 is provided on the inner circumferential wall of the transmission wheel 3 along its circumference. The two wall surfaces of each transmission tooth 32 which are sequentially provided along the circumference of the transmission wheel 3 are respectively a first surface 321 and a second surface 322 .

[0042] The one-way transmission member 4 is located in the annular area surrounded by the transmission wheel 3. The one-way transmission member 4 is installed at the end of the pressure roller 2 and the two are relatively fixed in the circumferential direction. Figure 6As shown, the pressure roller 2 includes a central shaft 21 and a sleeve 22 sleeved on the outside of the central shaft 21. One end of the central shaft 21 passes through the sleeve 22, and the cross-section of the end is non-circular, such as D-shaped. The one-way transmission member 4 is provided with a socket 40 for inserting the end of the central shaft 21, and the cross-section of the socket 40 is also non-circular, such as D-shaped.

[0043] The transmission pawl 41 is movably mounted on the one-way transmission member 4. The transmission pawl 41 can be placed in a state where it presses against the first surface 321 of any transmission tooth 32, thereby fixing the transmission wheel 3 and the one-way transmission member 4 relative to each other in the circumferential direction for synchronous rotation. Alternatively, the transmission pawl 41 can be placed in a state where it presses against the second surface 322 of any transmission tooth 32, thereby disengaging the transmission wheel 3 and the one-way transmission member 4. The elastic member 42 acts on the transmission pawl 41, causing the transmission pawl 41 to maintain a tendency to abut against the first surface 321. There are at least two transmission pawls 41, spaced apart along the circumference of the one-way transmission member 4. In this embodiment, there are two transmission pawls 41.

[0044] The arrangement direction of the first surface 321 and the second surface 322 of the transmission tooth 32 is defined as the clockwise direction of the transmission wheel 3, and the one-way transmission member 4 rotates relative to the transmission wheel 3 in the counterclockwise direction. The first surface 321 of the transmission tooth 32 is a surface perpendicular to the peripheral wall surface of the transmission wheel 3, and the second surface 322 is an inclined surface inclined along the clockwise direction of the transmission wheel 3 toward away from the one-way transmission member 4.

[0045] In this embodiment, one end of a transmission pawl 41 is rotatably mounted on the one-way transmission member 4. The rotation axis of the transmission pawl 41 is parallel to the rotation axis of the one-way transmission member 4. The other end of the transmission pawl 41 can abut against the transmission tooth 32. A fixing post 43 is mounted on the one-way transmission member 4. The elastic member 42 is a torsion spring, the coiled portion of which is mounted on the fixing post 43. One torsion spring arm is fixed to the one-way transmission member 4, and the other torsion spring arm abuts against the transmission pawl 41.

[0046] The one-way transmission member 4 is provided with a receiving groove 44, which is open on one side of the receiving groove 44 toward the transmission tooth 32. An axial hole 45 is provided on one wall surface of the receiving groove 44. One end of the transmission claw 41 is rotatably mounted in the axial hole 45 via a rotating shaft 46. The other wall surface of the receiving groove 44 can abut against the transmission claw 41 as a limit surface 48 to prevent the transmission claw 41 from rotating too far and being unable to reset.

[0047] The working process of the fixing structure of this embodiment is as follows:

[0048] The heating roller 1 rotates under the drive of the first gear 11, and the first gear 11 drives the transmission wheel 3 through the second gear 12;

[0049] During the rotation of the heating roller 1, the paper and the pressure roller 2 are in contact with each other, the pressure roller 2 rotates, and the paper passes through the nip zone. When the pressure roller 2 is synchronized with the paper speed, the number of teeth of the first gear 11 and the number of teeth of the tooth portion 31 are different, and the rotation speed of the transmission wheel 3 is lower than the rotation speed of the one-way transmission member 4. Since the first surface 321 and the second surface 322 of the transmission teeth 32 are arranged in the clockwise direction of the transmission wheel 3, the one-way transmission member 4 rotates counterclockwise relative to the transmission wheel 3. Since the rotation speed of the one-way transmission member 4 is higher than the rotation speed of the transmission wheel 3, the transmission claw 41 contacts the second surface 322 of the transmission teeth 32. At this time, the one-way transmission member 4 and the transmission wheel 3 are in a relatively independent rotation state, and the transmission wheel 3 does not provide power to the pressure roller 2.

[0050] When the speed of the pressure roller 2 and the paper are not synchronized, the rotation speed of the one-way transmission member 4 is reduced, and the rotation speed of the transmission wheel 3 is greater than the rotation speed of the one-way transmission member 4. At this time, the transmission claw 41 and the first surface 321 of the transmission tooth 32 are abutted, so that the transmission wheel 3 and the one-way transmission member 4 rotate synchronously, providing power for the pressure roller 2, reducing the friction required for the paper to drive the pressure roller 2, so as to prevent the problem of paper slipping and printing abnormality.

[0051] As can be seen from the above, when the speed of the pressure roller 2 and the paper is consistent, that is, when the pressure roller 2 does not experience speed loss, the working principle of the pressure roller 2 and the heating roller 1 is consistent with the existing fixing structure;

[0052] When the speed of the pressure roller 2 is inconsistent with that of the paper, that is, when the pressure roller 2 loses speed, the transmission wheel 3 will drive the one-way transmission part 4 to rotate to supplement power to the pressure roller 2, thereby ensuring the rotation speed of the pressure roller 2 during printing and eliminating the printing image problem caused by the speed loss of the pressure roller 2. In addition, the structural form of this embodiment can also improve the service life of the pressure roller 2 to a certain extent.

Claims

1. A fixing structure for an imaging device, comprising A heating roller (1) extends in a left-right direction and is rotatable around its axis; A pressure roller (2) extends in a left-right direction and can rotate around its axis. The pressure roller (2) is parallel to the heating roller (1), and a nip area for paper to pass through is formed between the two. It is characterized in that Also includes A first gear (11) is fixedly mounted on the end of the heating roller (1) and the two are coaxial; The transmission wheel (3) is annular, and a circle of teeth (31) is provided on the outer peripheral wall of the transmission wheel (3) along its circumference, and the teeth (31) is directly or indirectly meshed with the first gear (11), and the number of teeth of the first gear (11) is smaller than the number of teeth of the teeth (31), and a circle of transmission teeth (32) is provided on the inner peripheral wall of the transmission wheel (3) along its circumference, and two wall surfaces of each transmission tooth (32) arranged in sequence along the circumference of the transmission wheel (3) are respectively a first surface (321) and a second surface (322); A one-way transmission member (4) is mounted on the end of the pressure roller (2) and the two are relatively fixed in the circumferential direction, and the one-way transmission member (4) is located in the annular area surrounded by the transmission wheel (3); A transmission pawl (41) is movably mounted on the one-way transmission member (4), wherein the transmission pawl (41) can be in a state of pressing against a first surface (321) of any transmission tooth (32) so that the transmission wheel (3) and the one-way transmission member (4) are relatively fixed in the circumferential direction so as to rotate synchronously, and the transmission pawl (41) can be in a state of pressing against a second surface (322) of any transmission tooth (32) so that the transmission wheel (3) and the one-way transmission member (4) are disengaged. The elastic member (42) acts on the transmission claw (41), so that the transmission claw (41) maintains a tendency to abut against the first surface (321).

2. The fixing structure according to claim 1, wherein: One end of the transmission claw (41) is rotatably mounted on the one-way transmission member (4), the rotation axis of the transmission claw (41) is parallel to the rotation axis of the one-way transmission member (4), and the other end of the transmission claw (41) can abut against the transmission tooth (32).

3. The fixing structure according to claim 2, wherein: The arrangement direction of the first surface (321) and the second surface (322) of the transmission teeth (32) is defined as the clockwise direction of the transmission wheel (3), the one-way transmission member (4) rotates relative to the transmission wheel (3) in the counterclockwise direction, and the second surface (322) is an inclined surface inclined in the clockwise direction of the transmission wheel (3) toward a direction away from the one-way transmission member (4).

4. The fixing structure according to claim 2, wherein: The first surface (321) of the transmission tooth (32) is a surface perpendicular to the peripheral wall surface of the transmission wheel (3).

5. The fixing structure according to claim 2, wherein: The one-way transmission member (4) is provided with a receiving groove (44), the receiving groove (44) being open on one side facing the transmission tooth (32), and an axial hole (45) being provided on one wall surface of the receiving groove (44). One end of the transmission claw (41) is rotatably mounted in the axial hole (45) via a rotating shaft (46), and the other wall surface of the receiving groove (44) can abut against the transmission claw (41) as a limiting surface (48).

6. The fixing structure according to any one of claims 1 to 5, wherein: There are at least two transmission claws (41), which are arranged at intervals along the circumference of the one-way transmission member (4).

7. The fixing structure according to any one of claims 1 to 5, wherein: The first gear (11) and the tooth portion (31) are driven by a second gear (12). The first gear (11) is also fixed with a second gear (12) coaxial with the first gear (11). The second gear (12) is directly meshed with the tooth portion (31). The number of teeth of the first gear (11) is smaller than that of the second gear (12), and the number of teeth of the second gear (12) is the same as that of the tooth portion (31).

8. The fixing structure according to any one of claims 1 to 5, wherein: The pressure roller (2) comprises a central shaft (21) and a sleeve (22) sleeved on the outside of the central shaft (21); one end of the central shaft (21) passes through the sleeve (22), and the cross section of the end is non-circular; the one-way transmission member (4) is provided with a socket (40) for inserting the end of the central shaft (21); the cross section of the socket (40) is also non-circular.

9. An imaging device, characterized in that The fixing structure includes the fixing structure according to any one of claims 1 to 8.

Images