JP2010058965A - Paper feeding pressing device, and image forming device equipped with this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feed pressing device capable of preventing fatigue rupture caused by stress concentration due to the behavior of a tension spring, regulating the movements of the tension spring, and preventing the buckling of the spring. <P>SOLUTION: A bottom plate raising part 5 and a shaft 4 are rotatably held below a paper-feeding tray 1. When the paper-feeding tray 1 is set, a raising lever 35 and the shaft fitted with the shaft 4 of the bottom plate raising arm 5 are rotatably held, and a pressing lever 36 and the shaft are slidably/rotatably held on a device body side. A pressing coupling 34 is connected to a pressing motor 33 fitted with the pressing lever 36 and the shaft. The pressing tension spring 22 surrounded by a cylindrical regulation member 38 is provided between the raising lever 35 and the pressing lever 33. During paper feeding, the pressing lever 33 is rotated/driven with the pressing motor 33, and the raising lever 35 is rotated via the paper-feeding tension spring 22 for pressing. When the paper-feeding tray 1 is drawn, both sides of the shaft of the raising arm 5 and a pressing driving shaft 30 are almost simultaneously disconnected to be free. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a paper feeding and pressing device used for pressurization when feeding transfer paper loaded on a paper feeding tray, and an image forming apparatus including the same.

  In a paper feeding device such as a copying machine, a printer, a multifunction machine, and a FAX machine, a paper feeding / pressing device used for pressurization when feeding transfer paper loaded on a paper feeding tray is used.

  For example, in Patent Document 1, as a paper feeding device having a bottom plate raising mechanism that is simple and inexpensive and that does not deteriorate the operability of the cassette or tray, it is provided at a position below the bottom plate and fixed to a rotating shaft. The lifting lever, the pressure arm connected to the rotating shaft, the pressure spring stretched on the pressure arm, and the tension of the pressure spring in multiple steps according to the decrease in the paper load A changeable tension control mechanism, a sheet loading amount detection unit for detecting a sheet loading amount, and a control unit for controlling the tension control mechanism by detection of the sheet loading amount detection unit are disclosed.

Japanese Patent No. 3217162

  By the way, in this type of paper feeding and pressing device and a paper feeding device equipped with the same, the pressurized tension spring is released at a stroke, so there is also a reaction of the attached lever, and the spring is in a buckled state. Therefore, it may cause a swing in the perpendicular direction instead of the original pulling direction. In particular, the pressure tension spring for paper feed needs to be pressed against the paper feed roller with a predetermined pressure regardless of the amount of transfer paper that is set, so the spring constant is limited and the installation length can be freely determined. Since there are many cases where the length is not long, the length from the coil portion to the hook portion is generally long. For this reason, when a lateral swing occurs, stress concentration tends to occur at the rising portion from the coil portion, resulting in fatigue failure and a breakage accident.

  The present invention has been made in view of the above points, and prevents fatigue failure due to stress concentration in the behavior of the tension spring, restricts the movement of the tension spring, prevents buckling, and further reduces the cost. It is an object of the present invention to provide a paper feeding and pressing device that can be downed and an image forming apparatus including the same.

  According to a first aspect of the present invention, there is provided a sheet feeding and pressurizing apparatus according to the first aspect, wherein a sheet feeding tray, a bottom plate raising arm and a shaft rotatably held below the sheet feeding tray, the sheet feeding tray is an image of a copying machine, A rising lever and shaft rotatably held on the apparatus main body side so as to be fitted to the shaft of the bottom plate raising arm when set on the apparatus main body of the forming apparatus, and slidably and rotatably held on the apparatus main body side. The pressure lever and the shaft, the pressure joint connected to the pressure motor that fits the pressure lever and the shaft when the paper feed tray is set, and the pressure lever and the shaft are installed between the lift lever and the pressure lever. It comprises a pressure tension spring. During feeding, the pressure lever is driven to rotate by the pressure motor, the lifting lever is rotated through the paper feed tension spring to perform a predetermined pressure, and the pressure is applied. The feeding tray in pressure state In the paper feeding and pressurizing device in which the both sides of the ascending arm shaft and the pressurizing drive shaft are disconnected at the same time and become free when extracted, a cylindrical regulating member is installed around the pressurizing tension spring It is characterized by.

  According to a second aspect of the present invention, in the paper feeding and pressing device according to the first aspect, the inner diameter of the regulating member is larger than the outer diameter of the coil of the pressure tension spring.

  According to a third aspect of the present invention, in the paper feeding and pressing device according to the first or second aspect, the total length of the restricting member is a length obtained by subtracting the hook lengths at both ends from the free length of the pressure tension spring. It is characterized by that.

  According to a fourth aspect of the present invention, in the paper feeding and pressing device according to any one of the first to third aspects, the material of the restricting member is a semi-rigid resin.

  According to a fifth aspect of the present invention, there is provided a sheet feeding tray, a bottom plate raising arm and a shaft rotatably held below the sheet feeding tray, and when the sheet feeding tray is set in an apparatus main body of an image forming apparatus such as a copying machine. A lift lever and shaft rotatably held on the apparatus main body side so as to be fitted to the bottom plate lift arm shaft, a pressure lever and shaft slidably and rotatably held on the apparatus main body side, and the paper feed tray A pressure joint connected to a pressure motor that fits with the pressure lever and shaft, a pressure tension spring installed between the lift lever and the pressure lever, and slides on the paper feed tray A side fence that can be held and regulates the depth direction of the transfer paper, a convex cam member that is provided integrally with the side fence, an auxiliary pressure arm that is rotatably held on the apparatus body side, Depending on the position of the side fence when the auxiliary pressurizing tension spring installed between the auxiliary pressurizing arm and the lifting lever and the shaft, and when the paper feed tray is set in the main body of an image forming apparatus such as a copying machine, etc. The auxiliary pressure arm is rotated by the convex cam member, the auxiliary lever is rotated via the auxiliary pressure tension spring, and auxiliary pressure is applied. In addition, the pressurizing motor is rotated by the pressurizing motor, the raising lever is rotated through the paper feed tension spring to perform a predetermined pressurization, and the paper feed tray is pulled out in the pressurized state. In this case, both sides of the ascending arm shaft and the pressure drive shaft are disconnected at the same time so that the pressure tension spring becomes free. Similarly, the auxiliary pressure spring is returned by the auxiliary pressure arm returning. Free paper feed In pressure device, characterized in that installed the pressurized 圧引 Zhang spring and the auxiliary pressure 圧引 Zhang spring of at least one of the cylindrical regulating member around.

  According to a sixth aspect of the present invention, in the paper feeding and pressing device according to the fifth aspect, the inner diameter of the regulating member is larger than the outer diameter of the coil of the installed tension spring.

  According to a seventh aspect of the present invention, in the paper feeding and pressing device according to the fifth or sixth aspect, the total length of the restricting member is a length obtained by subtracting the hook lengths at both ends from the free length of the installed tension spring. It is characterized by doing.

  According to an eighth aspect of the present invention, in the paper feeding and pressing device according to any one of the fifth to seventh aspects, the material of the regulating member is a semi-rigid resin.

  According to a ninth aspect of the present invention, there is provided an image forming apparatus including the paper feeding and pressing device according to any one of the first to eighth aspects.

  According to the present invention, buckling and large swinging that can occur when the tension spring is released from the pressurized state at once are prevented by the restricting member, and by restricting the swinging (significant reduction in amplitude), Fatigue failure due to abnormal bending stress of the spring can be prevented.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings. In the embodiments described below, a printer will be described as an example. However, the present invention is not limited to the printer, and can be applied to various apparatuses that perform image formation.

  As described above, the pressure tension spring for paper feed must be pressed against the paper feed roller with a predetermined pressure regardless of the amount of transfer paper that is set, the spring constant is limited, and the installation length In many cases, it is not possible to determine freely. For this reason, it is generally a long shape from the coil portion to the hook portion. For this reason, when a lateral swing occurs, stress concentration tends to occur at the rising portion from the coil portion, leading to fatigue failure and fracture accident. In order to suppress this fatigue failure, the amount of displacement can be reduced by regulating the swinging motion. In the present invention, the length of the restriction member is reduced as long as possible so that the inner diameter of the regulating member is slightly larger than the outer diameter of the coil and the length is not buckled so as to suppress the behavior of the tension spring and prevent resistance. The metal pipe is made of resin because there is a possibility of scratches and abnormal noise due to rubbing on the metal pipe. Further, since the end portion of the hard resin is likely to be chipped by an impact, the impact is absorbed by a semi-hard material, and when the tension spring is released, it acts as a link between the anchors of the tension spring.

  The illustrated image forming apparatus is an application example of a so-called full-color printer. FIG. 1 is a central sectional view showing the outline of the full-color printer 60. The full-color printer 60 is a tandem (parallel-type) full-color image forming apparatus using an electrophotographic system, and an image forming unit (printer engine) 62 serving as an image forming unit is disposed at the center of the apparatus body. Immediately below that, a paper feeding unit 63 serving as a paper feeding device is disposed. The paper feed unit 63 is provided with, for example, four stages of paper feed trays 1a to 1d each serving as a storage unit for paper (sheet material). These paper feed trays 1 a to 1 d are provided so as to be able to be drawn out and stored with respect to the main body of the image forming apparatus 1. A reading unit (scanner) 65 for reading a document image is disposed above the printer engine 62. Further, a discharge tray 67 for discharging the transfer paper P on which an image has been formed is provided downstream of the printer engine 62 in the sheet material conveyance direction. A manual feed tray 68 serving as a sheet material storage unit for manually feeding the transfer paper P is provided on the upstream side of the printer engine 62 in the sheet material conveyance direction.

  In the printer engine 62, four images for yellow (Y), cyan (C), magenta (M), and black (K) are formed above the intermediate transfer belt 69 that is an endless belt constituting the paper transfer unit. Units 70 are juxtaposed. In each image forming unit 70, an electrophotographic process member or unit such as a charging unit, an optical writing unit, a developing unit, or a cleaning unit is disposed along the outer periphery of the drum-shaped photoconductors 71Y to 71K provided for each color. Has been.

  Although detailed illustration is omitted, the charging unit 73 performs a charging process on the surfaces of the photoconductors 71Y to 71K, and irradiates the surface of the photoconductor 71 with laser light from the optical writing unit 75. The developing unit 74 visualizes the electrostatic latent image formed on the surface of the photoreceptor 71 by exposure to toner, and the cleaning unit 73 removes and collects the toner remaining on the surfaces of the photoreceptors 71Y to 71K after transfer. Then, each color image is sequentially formed on the intermediate transfer belt 69, and the four color images are superimposed on the intermediate transfer belt 69 to form one color image. At that time, first, Y toner is developed by the Y image forming unit and transferred to the intermediate transfer belt 69. Next, in the C image forming unit, the C toner is developed and transferred to the intermediate transfer belt 69, and then the M toner is finally developed and transferred, and the K toner is developed and transferred. An image is formed. The four-color toner image transferred onto the intermediate transfer belt 69 is transferred to the transfer paper P fed from the paper feed unit 63, fixed by the fixing unit 77, and then discharged by the paper discharge roller 78. It is discharged to the tray 67. On the other hand, after the full-color toner image is transferred, the toner remaining on the surface of the intermediate transfer belt 69 is removed and collected by the belt cleaning unit 81.

  Each of the paper feed trays 1a to 1d, the manual feed tray 68, and the registration roller 79 are connected by a conveyance path 80, and the transfer paper P fed from an arbitrary paper supply location is registered via the conveyance path 80. It is conveyed to the roller 79. The transfer of the transfer paper P is temporarily stopped by the registration rollers 79, and the transfer paper P is transferred at a timing so that the positional relationship between the toner image on the intermediate transfer belt 69 and the leading edge of the transfer paper P becomes a predetermined positional relationship. Send it to the department. The registration rollers 79 function in the same manner for the transfer paper conveyed from the manual feed tray 68.

  Although detailed illustration is also omitted, in the scanner 65, a plurality of traveling bodies mounted with a document illumination light source and a mirror reciprocate to read and scan the document placed on the contact glass. The image information scanned by this traveling body is condensed on the imaging surface of the CCD installed behind by the lens and is read as an image signal by the CCD. The read image signal is digitized and subjected to image processing. Then, based on the image-processed signal, optical writing is performed on the surface of the photosensitive member by light emission of the laser diode LD in the optical writing unit, and an electrostatic latent image is formed. The optical signal from the LD reaches the photoconductor via a polygon mirror and a lens. An automatic document feeder 66 that automatically feeds the document onto the contact glass is mounted on the scanner 5.

  FIG. 2A is a perspective view showing a back side portion of the paper feed tray 1 according to the present invention. Guide portions 2 and 3 that guide insertion of the full-color printer 60 into the main body of the paper feed portion 63 are provided at the left and right ends of the paper feed tray 1 so as to protrude to the back side. A bottom plate raising arm shaft 4 is rotatably held at the box-shaped bottom of the paper feed tray 1, and a bottom plate raising arm 5 is fixed to the bottom plate raising arm shaft 4. Further, the end of the bottom plate ascending arm shaft 4 protruding from the tray rear side wall surface 6 of the paper feed tray 1 has a rising coupling from the main body side of the paper feed unit 63 (indicated by reference numeral 15 in FIG. 2B). ) And a drive pin 7 for transmitting rotation is provided. Then, by rotating the bottom plate raising arm shaft 4, the tip of the bottom plate raising arm 5 is lifted, the bottom plate (not shown) and the transfer paper (not shown) set on it are lifted, and the paper feeding roller (not shown) Display).

  A rear side fence 8 for restricting the rear of the slidable transfer paper is provided on the rear side of the paper feed tray 1 in the box shape, and a convex cam portion 9 is provided on the rear side fence 8. The paper feed tray 1 protrudes from the rear side wall surface 6. Accordingly, the length of the cam portion 9 protruding from the tray rear side wall surface 6 varies depending on the setting direction of the transfer paper (not shown).

  Protrusions 10 and 11 serving as a reference are provided on the tray rear side wall surface 6 of the sheet feeding tray 1 so that the position is determined when the sheet is set in the sheet feeding unit 63 main body. Further, a convex pressing portion 12 is provided so as to press a pressure driving shaft (indicated by reference numeral 30 in FIG. 4) when the paper feed tray 1 is set.

  FIG. 2B is a perspective view showing the paper feeding and pressing mechanism. A lift lever 14 and a lift coupling 15 are fixed to the lift lever shaft 16 and are rotatably held by a lift lever holding bracket (not shown) on the main body side plate 13 of the paper feed unit 63. When the paper feed tray 1 is set in the main body of the paper feed unit 63, the bottom plate raising arm shaft 4 and the drive pin 7 protruding from the notch 17 of the main body side plate 13 are engaged with the raising coupling 15. Further, the ascending lever 14 is urged so as to be in an arbitrary position (angle) in the free state so that the fitting with the ascending coupling 15 is ensured.

  A sensor 18 and a sensor 19 are provided on the raising lever holding bracket (not shown), and the position of the filler portion 20 of the raising lever 14 is detected. This is because the thickness of the transfer paper (not shown) on the paper feed tray is obtained by detecting the angle of the ascending lever 14 and functions as the remaining amount of transfer paper.

  A pressure lever 21 is installed at a position away from the raising lever 14. A pressure tension spring 22 is stretched between the raising lever 14 and the pressure lever 21, and a main regulating member 23 made of a pipe material is installed on the pressure tension spring 22. Since the main restricting member 23 has an inner diameter larger than the outer diameter of the coil of the pressure tension spring 22, it can move freely. At the time of pressurization, the pressure lever 21 is rotated, and the filler portion 24 of the pressure lever 21 is rotated until the pressure sensor 25 fixed to the pressure lever holder (not shown) is turned on. As a result, the pressure tension spring 22 is extended, and the transfer paper (not shown) is pressed against the sheet feeding roller (not shown) via the raising lever 14 correspondingly.

  An auxiliary pressure arm 26 is rotatably held between the raising lever 14 and the pressure lever 21 (the bracket is not shown). An auxiliary pressurizing tension spring 27 is stretched between the raising lever 14 and the auxiliary pressurizing arm 26, and an auxiliary regulating member 28 of a pipe material is installed on the auxiliary pressurizing tension spring 27. Since the auxiliary regulating member 28 has an inner diameter larger than the outer diameter of the coil of the auxiliary pressurizing tension spring 27, the auxiliary regulating member 28 can move freely.

  When the paper feed tray 1 is set in the main body of the paper feed unit 63, the cam portion 9 provided on the rear side fence 8 protrudes from the cutout portion 29 of the side plate 13, and the cam portion 9 causes the auxiliary pressure arm. 26 is rotated. As a result, the auxiliary pressurizing tension spring 27 is extended and acts to pull the raising lever 14, and is added to the stress caused by the pressurizing tension spring 22 described above. The cam portion 9 has a larger protrusion amount as the transfer paper (not shown) is wider, and the auxiliary pressure arm 26 rotates in accordance with the protrusion amount of the cam portion 9. It is configured to be stretched.

As an example of the specifications of each tension spring,
Pressure tension spring: Coil part outer diameter 7.7mm
Hook outer diameter 9.3mm
Free length (outside) 179.8mm
Coil length (64.4mm)
Auxiliary pressure tension spring: Coil part outer diameter 7.6mm
Hook outer diameter 9.1mm
Free length (outside) 98.6mm
Coil length (40.8mm)
This is just an example.

  As described above, since the pressure tension spring 27 needs to press the transfer paper against the paper feed roller with an arbitrary substantially constant force regardless of whether the transfer paper is large or small, the spring constant is determined. Therefore, in general, since the spring mounting position cannot be arbitrarily set, the tension spring has a long hook shape as in the embodiment.

In addition, as an example of the specifications of each regulating member,
Main regulating member: inner diameter 8mm, outer diameter 10mm, length 160mm
Auxiliary regulating member: inner diameter 8mm, outer diameter 10mm, length 80mm
Material: Polyvinyl chloride resin (semi-rigid)
This is just an example.

  As described above, the inner diameter of each regulating member is smaller than the outer diameter of the hook portion of the corresponding tension spring. However, since the regulating member is semi-rigid, it is slightly deformed (collapsed) and set in each tension spring. Therefore, there is no need to remove the regulating member from the tension spring during assembly, and it is desired to improve the efficiency of assembly.

In addition, this inventor tested the following material as a control member material in the process of examination. However, the metal pipe was not adopted because the surface of the tension spring could be damaged or worn, and abnormal noise was also considered.
-ABS resin pipe: inner diameter 10 mm, outer diameter 12 mm → result: almost abnormal behavior was suppressed.
・ Acrylic resin pipe: inner diameter 10 mm, outer diameter 12 mm → Result: Behavior was suppressed, but the end was damaged by impact ・ Semi-rigid PVC pipe: inner diameter 8 mm, outer diameter 10 mm → Result: Clearance with tension spring The braking effect was greater than that of the small size. Soft vinyl tube: Inner diameter 8 mm, outer diameter 10 mm → Result: Because of softness, the frictional resistance increases and the braking effect is large. However, as a buckling prevention, there is a large possibility of deformation, and there is further doubt about toner resistance.

  As a result, semi-rigid PVC pipes were used. As described above, since the inner diameter of the pipe is smaller than the outer diameter of the tension spring hook portion, once set, it does not come off easily, so the assemblability is very good. Moreover, since the obtained raw material was distributed to the market as a packaging material, it was available at a very low cost.

  Since this regulating member does not require any changes to other parts, it can be easily set even for machines that are operating in the market without the regulating member. It becomes a means.

  FIG. 2C is a perspective view showing the pressure drive mechanism. The pressure lever 24 is fixed to the pressure drive shaft 30 and is rotatably supported by a pressure lever bracket (not shown) and slidable. Further, the end of the pressure drive shaft 30 protrudes from the notch 31 of the main body side plate 13 to the inside of the side plate 13. The pressure drive shaft 30 is urged by a compression spring (not shown) installed between a bearing 32 fixed to a pressure lever bracket (not shown) and the pressure lever 24, and is pressed to the right in the figure. It has been.

  The pressure motor 33 is connected to a pressure coupling 34 for fitting with the pressure drive shaft 30. However, as described above, the pressurizing drive shaft 30 is normally biased in a direction away from the pressurizing motor 33, and therefore is not fitted. When the paper feed tray 1 is set, the convex pressing portion 12 provided on the tray rear side wall surface 6 of the paper feed tray 1 pushes the pressure drive shaft 30, whereby the pressure drive shaft 30 and the pressure are pressed. The coupling 34 is fitted to enable drive transmission.

  2D to 4 are perspective views schematically showing the operation of the pressure driving mechanism. The main regulating member 23 is shown in a sectional state, and the auxiliary regulating member 28 is not shown.

  FIG. 2D shows an initial state, that is, a state where the paper feed tray 1 is not set. The raising lever 35 is at a preset position (an angle at which the raising coupling 15 and the raising arm shaft 4 are securely fitted), while the pressure lever 36 is substantially free of the pressure tension spring 37. The rotation in the left direction is restricted by the long or main restricting member 38. The rotation of the auxiliary pressurizing arm (not shown, corresponding to the right hook portion 40 of the auxiliary pressurizing tension spring 39) is restricted by the free length of the auxiliary pressurizing tension spring 39.

  FIG. 3 shows a state immediately after the paper feed tray 1 is set. The raising lever 35 is engaged with the raising arm shaft 4, and the auxiliary pressure arm (not shown, corresponding to the right hook portion 40 of the auxiliary pressure tension spring 39) is rotated by the side fence cam portion (not shown), The auxiliary pressurizing tension spring 39 is extended, and the lift lever 35 is pulled and rotated (compared to FIG. 2D, the lift lever 35 rotates to the right). At the same time, the pressure lever 36 is also rotated by the interlocking of the pressure tension spring 37 or the main regulating member 38 due to the rotation of the raising lever 35. A rising lever 35a indicated by a broken line in the drawing indicates a position when there is little transfer paper.

  FIG. 4 shows the pressurized state and the release action. In contrast to FIG. 3, the pressure lever 36 is driven by a pressure motor (not shown) and rotated to a predetermined position. At that time, the pressure tension spring 37 is pulled, and the lift lever 50 is pulled by the amount of extension, and the transfer paper (non-display) is transferred to the feed roller (non-display) via the lift arm (non-display). It will be pressed with force.

  When the paper feed tray (not shown) is pulled out, both ends of each tension spring are released at a stretch in a load. Therefore, basically, each tension spring tries to contract around the coil portion, but the lift lever 50 is biased so as to return to the initial position (see FIG. 5). The movement moves in the direction (arrow 51 in the figure). In particular, the attachment portion 52 of the pressure tension spring 37 with the pressure lever 36 is lifted by the rotation 53 of the pressure lever 36, and the pressure lever 36 moves to the back side in the figure, so that the movement is very complicated. It becomes. Therefore, the pressure tension spring 37 is not only compressed, but also swings in the vertical direction (arrow 54 in the figure). Further, when there is no main regulating member 38, the pressure lever 36 is overrun to the broken line display position (arrow 56 in the figure), and as a result, the pressure tension spring is buckled. In particular, in the long hook-shaped tension spring of the example, the bending stress due to buckling and swinging was maximized at the rising portion from the coil portion to the hook portion (stress concentration), and fatigue failure occurred.

  However, in this embodiment, the main restricting member 38 prevents the overrun of the pressurizing lever 36 (prevents buckling of the pressurizing tension spring 37) and reduces or regulates the swing amplitude of the pressurizing tension spring 37, thereby reducing the stress concentration portion. Reduction of bending stress is realized.

  Also in the auxiliary pressurizing tension spring 39, the attachment position 58 of the auxiliary pressurizing arm 26 is largely displaced in the direction of the arrow 59 in the figure, and therefore buckling and swinging similar to the pressurizing tension spring 37 can be considered. A countermeasure similar to that of the tension spring is desired, but since this can also be easily realized with the same configuration as the above-described embodiment, the description thereof is omitted.

  That is, in the present invention, the buckling and large swing that occur when the tension spring is released from the pressurized state at once are prevented from buckling by the restricting member, and the swing is restricted (significant reduction in amplitude). Fatigue failure due to abnormal bending stress can be prevented. The setting of the inner diameter of the restricting member can be confirmed and set so that it does not become the resistance of the tension spring and the swing amplitude can be suppressed. The length of the restricting member can be set so that the tension spring cannot be largely buckled. The material of the restricting member can be set even when the outer diameter of the hook part is slightly larger than the outer diameter of the coil of the tension spring as in the example because semi-rigid resin is slightly flexible. This is based on the fact that a soft resin cannot withstand buckling, while a hard resin is assumed to be damaged by an impact on the end face. In other aspects, the point that can be obtained at the lowest price among the samples obtained this time is also a point of choice.

1 is a central sectional view of a full-color printer according to an embodiment of the present invention. The perspective view (A) which shows the back | inner side part of the paper feed tray which concerns on this invention, The perspective view (B) which shows a paper feed pressurization mechanism part, The perspective view (C) which shows a pressurization drive mechanism part, A pressurization drive mechanism (D) which shows typically the initial state of operation | movement of (D) Perspective view schematically showing the operation of the pressure drive mechanism Perspective view schematically showing the operation of the pressure drive mechanism

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a-1d: Paper feed tray 2, 3: Guide part 4: Bottom plate raising arm axis | shaft 5: Bottom plate raising arm 6: Tray rear side wall surface 7: Drive pin 8: Rear side fence 9: Cam part 10, 11: Convex Part 12: Pushing part 13: Main body side plate 14: Lifting lever 15: Lifting coupling 16: Lifting lever shaft 17: Notch part 18, 19: Sensor 20: Filler part 21: Pressure lever 22: Pressure tension spring 23 : Main regulating member 24: Filler portion 25: Pressure sensor 26: Auxiliary pressure arm 27: Auxiliary pressure tension spring 28: Auxiliary regulating member 29: Notch portion 30: Pressure drive shaft 31: Notch 32: Bearing portion 33: Pressure motor 34: Pressure coupling 35, 35a: Lift lever 36: Pressure lever 37: Pressure tension spring 38: Main regulating member 39: Auxiliary pressure tension spring 40: Right foot Part 61: full color printer 62: image forming unit (printer engine)
63: Paper feeding unit 65: Reading unit (scanner)
66: Automatic document feeder 67: Paper discharge tray 68: Manual feed tray 69: Intermediate transfer belt 70: Image forming units 71Y to 71K: Photoconductor 72: Cleaning unit 73: Charging unit 74: Development unit 75: Optical writing unit 77: Fixing unit 78: paper discharge roller 79: registration roller 80: conveyance path 81: belt cleaning unit P: sheet material

Claims (9)

A sheet feeding tray, a bottom plate raising arm and a shaft rotatably held below the sheet feeding tray, and a shaft of the bottom plate raising arm when the sheet feeding tray is set in an apparatus main body of an image forming apparatus such as a copying machine. When the paper feed tray is set, the lifting lever and shaft rotatably held on the apparatus main body side, the pressure lever and shaft slidably and rotatably held on the apparatus main body side, and the paper feed tray are set. A pressure joint connected to a pressure lever and a pressure motor fitted to the shaft, a pressure tension spring installed between the lift lever and the pressure lever,
At the time of paper feeding, the pressure lever is rotated by the pressure motor, the lifting lever is rotated via the paper feed tension spring to perform a predetermined pressure, and the paper feed tray is in the pressurized state. In the sheet feeding and pressing device in which both sides of the ascending arm shaft and the pressure driving shaft are disconnected at the same time and become free,
A sheet feeding and pressing device, wherein a cylindrical regulating member is provided around the pressing tension spring. The sheet feeding and pressing device according to claim 1,
The sheet feeding and pressing device, wherein an inner diameter of the regulating member is larger than an outer diameter of a coil of the pressing tension spring. The sheet feeding and pressing device according to claim 1 or 2,
2. A sheet feeding and pressing apparatus according to claim 1, wherein the total length of the regulating member is set to a length obtained by subtracting a hook portion length at both ends from a free length of the pressing tension spring. In the paper feed pressurizing device according to any one of claims 1 to 3,
A sheet feeding and pressing device, wherein the regulating member is made of semi-rigid resin. Feeding tray, bottom plate raising arm and shaft rotatably held below the feeding tray, and fitting with the bottom plate raising arm shaft when the feeding tray is set in the main body of an image forming apparatus such as a copying machine The lift lever and shaft rotatably held on the apparatus main body side, the pressure lever and shaft slidably and rotatably held on the apparatus main body side, and the pressurization when the paper feed tray is set. A pressure joint connected to a pressure motor fitted to the lever and the shaft, a pressure tension spring installed between the lift lever and the pressure lever, and slidably held on the paper feed tray, A side fence for regulating the depth direction, a convex cam member provided integrally with the side fence, an auxiliary pressure arm rotatably held on the apparatus main body side, the auxiliary pressure arm and the Auxiliary pressure tension spring installed between the raising lever and the shaft, and the convex cam member depending on the position of the side fence when the paper feed tray is set in the main body of an image forming apparatus such as a copying machine. The auxiliary pressurizing arm is rotated, the auxiliary lever is rotated through the auxiliary pressurizing tension spring to perform auxiliary pressurization, and during paper feeding, in addition to the auxiliary pressurization, the pressurizing motor When the pressurizing lever is rotated, the raising lever is rotated via the paper feed tension spring to perform a predetermined pressurization, and the paper feed tray is pulled out in the pressurized state, the lift arm shaft and Both sides of the pressure drive shaft are disconnected at the same time and the pressure tension spring becomes free. Similarly, the auxiliary pressure spring is also freed by the return of the auxiliary pressure arm. In the device
A sheet feeding and pressurizing apparatus, wherein a cylindrical regulating member is provided around at least one of the pressurizing tension spring and the auxiliary pressurizing tension spring. The sheet feeding and pressing device according to claim 5.
A paper feeding and pressing device, wherein an inner diameter of the regulating member is larger than a coil outer diameter of an installed tension spring. The sheet feeding and pressing device according to claim 5 or 6,
2. A sheet feeding and pressing apparatus according to claim 1, wherein the total length of the regulating member is a length obtained by subtracting the hook lengths at both ends from the free length of the installed tension spring. In the paper feed pressurizing device according to any one of claims 5 to 7,
A sheet feeding and pressing device, wherein the regulating member is made of semi-rigid resin. An image forming apparatus comprising the sheet feeding and pressing device according to claim 1.