JP2008170846A - Joined structure, rotating body supporting device, drive transmitting device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide joined structure in which a bar-like member is joined and fixed to a plate-like member firmly at high fitting accuracy (accuracy in fitting position and squareness) by welding, and to provide a rotating body supporting device, a drive transmitting device and an image forming apparatus. <P>SOLUTION: The joined structure (1) has the plate-like member (10) where a through-hole (15) for welding is formed, and the bar-like member (20) which is joined and fixed by welding in such a state that its end face (21) comes into contact with the part (12) of the surface including the through-hole of the plate-like member. The through-hole of the plate-like member is formed so that its aperture area may be narrower than the area of the end face of the bar-like member and it may be positioned nearly in the center part of the end face, and also at least a part of the through-hole of the plate-like member and at least a part of the end face of the bar-like member are welded (30). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a joining structure, a rotating body support device, a drive transmission device, and an image forming apparatus.

  Conventionally, a rotating shaft (shaft) for rotatably supporting a rotating body such as a gear is joined and fixed to a plate-like member such as a sheet metal, and the rotary shaft and the plate-like member are joined and fixed by welding. There is a bonded structure.

  For example, a shaft having an end face with a stepped portion formed on the outer peripheral edge portion with a convex portion is joined to a thrust bearing formed with a through hole into which the convex portion is fitted with a gap. There is known a hydrodynamic bearing device in which the entire circumference of a part is fixed by welding by laser irradiation (Patent Document 1).

  There is also known a ceramic structure in which a stud to which a rotating radiating fin is attached is fixed by brazing welding to a bottom plate having a brazing resist film formed in a peripheral portion except for a central portion where the stud is welded. (Patent Document 2).

Japanese Patent Laid-Open No. 2004-183809 JP-A-5-109949

  The present invention relates to a joined structure in which a rod-like member is firmly fixed to a plate-like member by welding with high attachment accuracy (accuracy such as attachment position and perpendicularity), and a rotating body including the structure A support device, a drive transmission device, and an image forming apparatus are provided.

In the joined structure of the invention (A1), the plate-like member in which the through-hole for welding is formed and the surface portion including the through-hole of the plate-like member are contacted and fixed by welding. A rod-shaped member,
The through hole of the plate-like member is formed so as to have an opening area narrower than the area of the end face of the rod-like member and located at a substantially central portion of the end face, and at least a part of the through hole of the plate-like member; The rod-shaped member is welded to at least a part of the end surface.

  Further, the joined structure of the present invention (A2) is an opening in which the through hole of the plate-like member is welded to the entire circumference of the through hole in one welding operation in the joined structure of the invention A1. It is formed by area.

  Moreover, the joined structure of the invention (A3) is the joined structure of the invention A1 or A2 in which the rod-shaped member is formed in a straight rod shape.

  Furthermore, the rotating body support device of the present invention (B) includes the joint structure according to any one of the above inventions A1 to A3, wherein the rod-shaped member is a rotating shaft that rotatably supports the rotating body, and rotates on the rotating shaft. The body is supported.

  Further, in the drive transmission device according to the present invention (C), at least one part of the joining structure part for joining and fixing the rotating shaft of the rod-like member that rotatably supports the rotating body used for transmitting the rotational power to the plate-like member, It is comprised by the joining structure in any one of said invention A1-A3, It is characterized by the above-mentioned.

  The image forming apparatus of the invention (D) is characterized in that at least a part of the drive transmission device for transmitting rotational power is constituted by the drive transmission device of the invention C.

  According to the joined structure of the invention A1, the rod-like member is firmly fixed to the plate-like member by welding with high attachment accuracy.

  In the joined structure of the invention A2, the rod-like member is attached to the plate-like member with a simplified work amount as compared with the case where the structure of the invention is not provided.

  In the joined structure of the invention A3, compared to the case where the structure of the invention is not provided, the rod-like member does not form a part such as a pedestal part for expanding the end face to be welded, for example. In addition, it is possible to avoid wasteful cost increase due to cutting or removal of the material of the rod-shaped member accompanying the formation of the part for widening.

  According to the rotating body support device of the invention B, the rotating shaft that rotatably supports the rotating body is welded to the plate-like member firmly and with high mounting accuracy, compared with the case where the configuration of the invention is not provided. In addition, the rotating body supported by such a rotating shaft can smoothly and accurately rotate.

  According to the drive transmission device of the invention C, in at least one portion of the joint structure portion constituted by the joint structure of any of the inventions A1 to A3, the rotation shaft of the rod-shaped member is relative to the plate-shaped member. It is firmly and firmly fixed by welding with high mounting accuracy, and the rotating body supported by the rotating shaft in such a joined structure rotates smoothly and accurately.

  According to the image forming apparatus of the invention D, at least one part of the drive transmission device constituted by the drive transmission device of the invention C is constituted by the joint structure of any of the inventions A1 to A3. The rotating shaft of the rod-shaped member in the bonded structure is firmly fixed to the plate-shaped member by welding with high mounting accuracy, and a rotating body supported by the rotating shaft in such a bonded structure is provided. By rotating smoothly and accurately, a high-quality image can be formed as compared with the case where the configuration of the present invention is not provided.

[Embodiment 1]
1 and 2 show a joint structure and a gear support device according to Embodiment 1 of the present invention. FIG. 1 is a schematic cross-sectional view showing the overall structure of the structure and device, and FIG. It is an enlarged explanatory view showing the welded portion (state when viewed from the sheet metal side).

  The joint structure 1 is mainly composed of a sheet metal 10 in which a through-hole 15 for welding is formed and a rotary shaft 20 in which one end face 21 is in contact with a surface portion including the through-hole 15 of the sheet metal and is fixed by welding. It is configured. Further, the gear support device 4 is configured to rotatably support the gear 40 on the rotating shaft 20 of the joint structure 1, and in short, has a configuration including the joint structure 1.

  The sheet metal 10 has a plate-like form in which at least the surface portion 12 on which the rotating shaft 20 is welded and fixed is a flat surface, and is made of a material such as a metal or an alloy that can be welded as desired. One rotating shaft 20 may be of any form that can rotatably support the gear 40. In this embodiment, the rotating shaft 20 is formed of a straight columnar shape, such as a metal or an alloy that can be welded as desired. Consists of materials. Further, the rotary shaft 20 is formed of a circular plane in which an end surface 21 at an end portion to be bonded and fixed by welding is cut (or cut) as a plane perpendicular to the rotation center line (two-dot chain line) L. ing.

  Here, each “plane” in the sheet metal 10 and the rotating shaft 20 is a smooth surface, but there is an unnecessary gap when the planar portion to be joined to the sheet metal 10 and the end surface of the rotating shaft are brought into contact with each other. Any surface shape that can be brought into close contact with each other is not required.

  Further, as shown in FIG. 2, the welding through-hole 15 in the sheet metal 10 is a hole formed with an opening area narrower than the area of the end face 21 of the rotating shaft 20, and the rotating shaft 20 is joined by welding. The fixed portion is formed so as to be positioned at a substantially central portion of the end surface 21. In this embodiment, since the end surface 21 of the rotating shaft 20 is circular as described above, the substantially central portion of the end surface 21 is centered on the center point of the circle (the symbol + indicated by the symbol O in FIG. 2). It becomes the part included in. Moreover, although the through-hole 15 has an opening formed in a circular shape, the opening shape may be a shape other than a circle (such as a regular polygon) if necessary.

  Further, as shown in FIG. 2, the sheet metal 10 and the rotating shaft 20 are welded to a portion that becomes the through hole 15 of the sheet metal 10 and a part of the end surface 21 of the rotating shaft by a predetermined welding method. Reference numeral 30 in FIG. 1 indicates a portion to be welded. In this embodiment, three locations (the portion included in the dotted circle in the figure are welded portions) 31 to 33 between the sheet metal portion that becomes the through hole 15 and the end surface 21 are welded. Since at least a part of the through hole 15 of the metal plate 10 and at least a part of the end surface 21 of the rotating shaft 10 are welded, the welding result (state) can be visually recognized.

  Incidentally, about this welded portion, it may be one place, a plurality of places other than three places, or the entire circumference of the through-hole 15, but the mounting strength, workability, etc. Considering about three places is preferable. Further, as the welding method, for example, a laser welding method that does not require a filler material is applied, but other welding methods may be used.

  The gear 40 is one of the gears in a rotation transmission device (or mechanism) that transmits rotational power by meshing a plurality of gears, for example, and is rotatably attached to the rotary shaft 20 that is joined and fixed to the sheet metal 10 by welding. .

  Such a joining structure 1 or the gear support device 4 is manufactured as follows, for example.

  First, as shown in FIGS. 3 and 4, the rotary shaft 20 to be welded is fitted into the rotary shaft accommodation holding recess 102 formed in the welding work table 100 with the end surface 21 being the upper surface. The rotary shaft accommodation holding recess 102 can accommodate the rotary shaft 21 so as to be fitted at a predetermined position and can stably hold the rotary shaft 21 in a predetermined posture, and the end surface 21 of the rotary shaft 20 when the rotary shaft 21 is accommodated. Is formed in a dimensional shape that protrudes from the table surface 101 (FIG. 4).

  Subsequently, the sheet metal 10 to be welded is kept on the welding work table 100 on which the rotating shaft 20 is held such that the surface portion 12 including the through hole 15 is in contact with the end surface 21 of the rotating shaft. Attach to.

  The mounting of the sheet metal 10 is performed, for example, as illustrated in FIG. That is, first, a plurality of sheet metal mounting positioning pins 106, 107,... Are fixedly provided on a surface portion of the work table 100 away from the rotary shaft housing and holding recess 102, while the rotary shaft 20 of the sheet metal 10. Positioning for positioning the mounting state of the sheet metal 10 by inserting the positioning pins 106, 107 into positions corresponding to the positioning pins 106, 107,... Of the work table 100 when the welding position is used as a reference. Holes 16, 17,... Are formed in advance. Then, the sheet metal 10 is mounted by attaching the sheet metal 10 so that the positioning pins 106, 107,... Of the work table 100 are inserted into the positioning holes 16, 17,. At this time, for example, fixing jigs 112 and 113 such as screw fixing type for holding the mounting state of the sheet metal 10 are attached to the positioning pins 106, 107,... After the sheet metal 10 is mounted. .

  Thus, the sheet metal 10 is maintained in a state where the surface portion 12 including the through hole 15 is in surface contact with the end surface 21 of the rotating shaft 20 held by the work table 100, and the through hole 15 is rotated by the rotating shaft. It is kept in a state where it is located at the center of the end face 21 of the 20. In addition to this, by attaching the fixing jigs 112 and 113, the surface portion 12 of the sheet metal 10 is held in close contact with the end surface 21 of the rotating shaft 20.

  After the sheet metal 10 is mounted on the work table 100, welding is performed between a corresponding portion of the through hole 15 of the sheet metal 10 and a portion of the end surface 21 of the rotary shaft 20 that contacts this portion. Reference numeral 3 in FIG. 4 indicates a welding work target portion. In this welding, when there are three parts to be welded (symbols 31 to 33 in FIG. 2), the welding operation (in this example, laser irradiation) is performed three times. When laser welding is performed, the sheet metal portion of the through-hole 15 and the end surface 21 portion of the rotary shaft 20 are in a state of being discolored in a different color from the other portions, so that the welding result can be visually confirmed. it can.

  In the joint structure 1 manufactured in this way, the rotating shaft 20 is accurately and firmly joined to a predetermined attachment site (surface portion 12 including the through hole 15) of the metal plate 10 without any positional displacement by welding. At the same time, it is bonded and fixed at a high squareness.

  On the other hand, for example, as illustrated in FIG. 7, a convex portion 28 is formed on the end surface 21 of the rotating shaft 20 to form a stepped end surface structure, and the convex portion 28 is inserted on the sheet metal 10 side. When the through-hole 18 is formed and welding is performed in a state in which the convex portion 28 is inserted into the through-hole 18 and the rotary shaft is joined and fixed, the following problems tend to occur. .

  That is, in this case, a clearance S of about 0.05 mm is usually provided between the convex portion 28 and the through hole 18, and the convex portion 28 of the rotating shaft 20 is inserted into the through hole 18 of the sheet metal 10. Due to the presence of S, the convex portion 28 and the through-hole 18 are drawn closer to each other at the first welded portion, whereby the rotating shaft 20 is in any direction along the surface of the sheet metal 10 (arrows B1, B2, etc.). The accuracy of the mounting position is inferior because it is fixed by welding in a state of being offset in the direction of At this time, when the gap S is large, the entire rotating shaft 20 may be welded and fixed in a state tilted in the direction indicated by the double arrow C, whereby the squareness accuracy is inferior. .

  In addition to this, as shown in FIG. 8, the sheet metal 10 and the rotation shaft 20 that do not form the through holes 18 and the protrusions 28 in the above example are prepared, and the end surface 21 that is a plane of the rotation shaft 20 is formed on the end surface 21 of the sheet metal 10. When welding is performed in a state where it is brought into contact with the surface 13 made of a flat surface and the rotary shaft is joined and fixed, the following problems tend to occur. In this case, for example, laser welding is applied as the welding method, and the periphery of the end of the rotating shaft 20 that is to be joined to the sheet metal 10 can be joined, but is substantially the same as the above example described with reference to FIG. In addition, the rotary shaft 20 is welded and fixed in a state in which it is offset in any direction along the surface of the sheet metal 10 (directions of arrows B1, B2, etc.) under the influence of the fluctuation caused by the welding of the portion to be welded first. Therefore, the accuracy of the mounting position may be inferior.

  Further, when spot welding is applied instead of the laser welding, for example, as shown in FIG. 8, spot welding can be performed aiming at the center portion of the end surface 21 of the rotating shaft 20 from the sheet metal 10 side. . However, in this case, the mounting accuracy of the rotating shaft 20 may be inferior, as in the case of performing the laser welding. Further, in the case of spot welding, the welded portion cannot be visually recognized, which may cause, for example, a decrease in attachment strength due to poor welding.

  The gear support device 4 is completed by attaching the gear 40 to the rotating shaft 20 of the joint structure 1 manufactured as described above. In this case, as described above, since the rotary shaft 20 is bonded and fixed to the sheet metal 10 with high positional accuracy and squareness accuracy, the gear 40 that is rotatably supported by the rotary shaft 20 is also in an accurate position. Moreover, it comes to rotate with an accurate posture.

  In this embodiment, for example, a bonded structure 1 having the following conditions was manufactured.

  That is, an electrogalvanized steel sheet (electroplating original plate: SECC) having a thickness of 1 mm is used as the sheet metal 10, and the rotary shaft 20 joined and fixed thereto is a straight having a diameter of 6 mm and a length of 25 mm. A stainless steel (SUS) shaft having a cylindrical shape was used. Further, a circular through hole 15 having a diameter of 4 to 5 mm was formed at a predetermined location of the sheet metal 10. Then, the sheet metal 10 and the rotating shaft 20 are mounted on a welding work table, and the position is fixed and held so that the end surface 21 of the rotating shaft 20 is in contact with the surface portion including the through hole 15 of the sheet metal 10. After that, three places around the through hole 15 were laser welded. Laser welding was performed, for example, using a laser processing machine (manufactured by Mitsubishi Electric Corporation: 3020HT) and using a sheet metal 10 having a thickness of 1 mm, and setting the output of the laser transmitter to 1 kW.

  In the joined structure 1 having this condition, the rotary shaft 20 was firmly joined and fixed to the sheet metal 10 at an accurate position by welding, and was joined and fixed at a squareness of approximately 90 °. In addition, you may perform laser welding with respect to the circumference | surroundings (all circumferences) of the through-hole 15 (it is made to make 1 round).

[Modifications of Embodiment 1]
In Embodiment 1, although the case where the through-hole 15 of the magnitude | size which can carry out the laser welding to three places with respect to the sheet metal 10 was shown was shown, in addition to this, for example, as shown in FIG. You may form the small through-hole 16 which consists of an opening area where the perimeter part of a through-hole is welded by one welding operation. In this case, the hatched portion indicated by reference numeral 35 in FIG. 5 is welded to the entire peripheral portion of the through hole 16. Further, such a through hole 16 is formed as a circular through hole having a diameter of about 1 to 2 mm, for example, in the case of the specific example described above. Furthermore, in the case where the hole diameter of the through hole 16 is small and the mounting strength of the rotating shaft 20 may be insufficient, in addition to laser welding to the through hole 16, for example, the end of the rotating shaft 20 joined to the sheet metal 10 Laser welding around the part 21 may be performed in combination.

  Further, in the first embodiment, as illustrated in FIG. 6, the rotating shaft 20 is a circle having an outer diameter larger than that of the main body portion 22 on the end portion side serving as the end surface 21 of the cylindrical shaft main body portion 22. What formed the plate-shaped base part 24 can also be used. In this case, since the area of the end face 21 joined and fixed to the sheet metal 10 is increased by the amount of the pedestal portion 24, the rotary shaft 20 can be joined and fixed in a more stable state. On the other hand, the material cost increases as much as the base portion 24 is formed. Further, when the pedestal portion is formed by cutting with a lathe, the material of the shaft end portion 22 is removed by cutting, resulting in waste.

  Furthermore, in Embodiment 1, although the case where the rotating shaft 20 was joined and fixed was demonstrated, it replaces with the rotating shaft, and you may make it join and fix the rod-shaped member used for another use. In the first embodiment, the case where one rotary shaft 20 is joined and fixed has been described. Needless to say, a plurality of rotary shafts 20 may be joined and fixed. Further, the through holes 15 and 17 are not limited to circular openings, but may have other opening shapes.

  In addition, in Embodiment 1, although the case where the gear 40 was attached to the rotating shaft 20 was demonstrated, it replaced with a gearwheel and supported rotating bodies, such as a cylindrical roll and a rotor of an electric motor, so that rotation was possible. It may be. Such a rotating body support device that supports various rotating bodies can be applied to a gear-type rotation transmission device and various devices that require the rotation transmission device.

[Embodiment 2]
9 and 10 show the image forming apparatus 5 according to the second embodiment to which the gear support device 4 including the joint structure 1 according to the first embodiment is applied and the drive transmission device 7 used therefor. .

  As shown in FIG. 9, the image forming apparatus 5 forms a toner image based on the image information in the apparatus main body (not shown), and finally transfers the toner image to the sheet-like recording paper 9. An image forming device 50, a fixing device 60 for fixing the toner image by passing the recording paper 9 onto which the toner image has been transferred, and a paper feeding device 65 for transporting and supplying the recording paper 9 to the image forming device 50. Is mainly equipped.

  The image forming device 50 can form and transfer a toner image using, for example, a known electrophotographic method. Specifically, a drum-shaped photoconductor 52 that is rotationally driven in the direction of the arrow is provided, and a charging device 53 that uniformly charges the surface (image holding surface) of the photoconductor 51 around the photoconductor 52. An exposure device 54 that irradiates the surface of the charged photoreceptor 52 with light based on image information (signal) to form a latent image having a potential difference, and a toner image is transferred and attached to the latent image to be visualized as a toner image. Developing device 55, transfer device 56 for transferring the toner image onto paper 9 supplied from paper supply device 65, and cleaning device for removing toner remaining on the surface of photoconductor 52 after transfer and cleaning. 57 is mainly arranged.

  Of these, the photosensitive member 52 is formed by forming a photoconductive layer made of an organic photosensitive material on the peripheral surface of a substrate having a cylindrical shape or the like. As the charging device 53, a charging member such as a charging roll is installed in contact with or close to the surface of the photoreceptor 52, and a predetermined charging voltage is applied to the charging member from a power supply device (not shown). Yes. As the exposure device 54, a device constituted by an LED array, a semiconductor laser scanning device or the like is used. The exposure device 54 receives image information input from an externally connected device such as an image reading device, an information storage medium reading device, a personal computer or the like connected or equipped to the image forming device 1 with an image processing device (not shown) at the time of image formation. An image signal obtained by performing a required process is input.

  Further, the developing device 55 is equipped with a developing roll for transporting and supplying toner constituting the developer contained therein to a developing position facing the photoconductor 52, and a power supply device (not shown) is connected to the developing roll. A device that applies a predetermined developing voltage is used. As the transfer device 56, a transfer member such as a transfer roll is installed in contact with or close to the surface of the photosensitive member 52, and a predetermined transfer voltage is applied to the transfer member from a power supply device (not shown). Yes. As the cleaning device 57, a device equipped with a cleaning member such as a cleaning blade whose tip is in contact with the surface of the photosensitive member 52 after the transfer with a predetermined pressure is used.

  The fixing device 60 is fixed in contact with a heating roll 62 that is heated to a predetermined temperature and is driven to rotate in the direction of the arrow inside the main body 61 with a predetermined pressure so as to be substantially along the axial direction of the heating roll 62. And a pressure member 63 such as a pressure roll for forming a pressure contact portion. The fixing by the fixing device 60 is to heat and press the toner image or the like by introducing the paper 9 on which the toner image has been transferred into the fixing pressure contact portion between the heating roll 62 and the pressure member 63 and passing it. Done in

  The paper feeding device 65 includes a paper container 66 that is accommodated in a state where a plurality of sheet-like recording papers 9 to be supplied to the image forming device 50 are stacked, and the paper 9 that is accommodated in the paper container 66. It is mainly provided with a sending device 67 for feeding one by one. A plurality of paper containers 61 are provided as necessary. Further, the paper feeding device 60 is a pair of paper transporting rolls 68a, 68b, 68c, for transporting the paper 9 from the paper container 61 to the transfer section of the image forming device 50 (between the photosensitive member 52 and the transfer device 56). ... and a paper conveyance path composed of a conveyance guide member or the like. The paper conveyance path is also provided between the image forming device 50 and the fixing device 60 and between the fixing device 60 and a paper discharge unit (tray or the like) 69. For example, on the paper discharge side of the fixing device 60, a discharge roll pair 68e for discharging and transporting the fixed paper 9 to the paper discharge unit 69 is installed.

  Basic image formation by the image forming apparatus 1 is performed as follows.

  When the image formation start command signal is received, the photoconductor 52 starts rotating in the image forming apparatus 50. Subsequently, after the surface of the rotating photoconductor 52 is charged to a predetermined charging potential by a charging device 53 to which a charging voltage is applied, the surface of the charged photoconductor 52 is operated based on an image signal. Light is exposed from the exposure device 54 to form a latent image having a predetermined latent image potential. Next, the electrostatic latent image is developed with toner when it passes through the developing device 55 to which a developing voltage is applied, and becomes a toner image.

  Thereafter, the toner image on the photosensitive member 52 is transferred to the recording paper 9 conveyed at a predetermined timing from the paper feeding device 60 through the paper feeding path in the transfer portion facing the transfer device 56 to which the transfer voltage is applied. Is transferred electrostatically. The sheet 9 on which the toner image has been transferred is conveyed so as to be introduced into the fixing device 60, and a fixing contact portion between the heating roll 62 and the pressure member 63 that is heated and held at the fixing temperature in the fixing device 60. The toner image is fixed on the paper 9 by being heated and pressurized when passing. Thereafter, the sheet 9 after fixing is discharged to the sheet discharge unit 69 through the discharge path and stacked and accommodated.

  As a result, the basic printing operation for one sheet is completed. Further, when there are a plurality of print instructions, the above-described series of operations is similarly repeated for the number of prints. After completion of the transfer, the photosensitive member 52 is cleaned by removing toner and paper dust remaining on the surface thereof by a cleaning device 57.

  As shown in FIGS. 9 and 10, the image forming apparatus 5 has a drive transmission device 7 for transmitting rotational power for rotating the photosensitive member 52 in the image forming device 50.

  The drive transmission device 7 is constituted by a plurality of helical gears 71 to 73 for rotating transmission, in which the rotational power of the electric motor 80 for rotational driving meshes with the helical gear 81 for driving the rotary shaft of the electric motor 80. This is transmitted to a rotating gear 74 that finally rotates the photosensitive member 52 through a gear train.

  The first helical gear 71 and the second helical gear 72 in the gear train are two-stage gears each having large-diameter tooth portions 71a and 72a and small-diameter tooth portions 71b and 72b. Further, the three helical gears 71 to 73 constituting the gear train are respectively attached to the three rotary shafts 20A, 20B, and 20C fixed to the support frame plates 70A and 70B arranged so as to face each other with a gap therebetween. While being rotatably supported, each tooth portion meshes with an adjacent predetermined gear (tooth portion).

  The three rotary shafts 20A, 20B, and 20C are thin cylindrical rod-like members, and the end surface 21 on one end side thereof is in contact with one support frame plate 70B and joined and fixed by welding, while the other end The part 26 is attached in a state of being inserted into an insertion hole (not shown) formed in the other support frame plate 70A.

  Further, as shown in FIG. 11, the rotary shafts 20 </ b> A, 20 </ b> B, and 20 </ b> C have an end surface 21 at one end thereof connected to the rotary shaft (rod-like member) 20 in the joint structure 1 or the gear support device 4 according to the first embodiment. It is attached with the same structure (refer FIG. 1 etc.). That is, the welding through-holes 15 (or 16) having the above-described configuration are respectively formed in the portions of the support frame plate 70B where the end surfaces 21 of the rotary shafts 20A, 20B, and 20C are to be joined and fixed. With the end surfaces 21 of the shafts 20A, 20B, and 20C in contact with the surface portions including the through holes 15 (16) of the support frame plate 70B, respectively, at least a part of the through holes 15 (16) and It joins and fixes by welding at least one part of the end surface 21 of each rotating shaft.

  As described above, the rotary shafts 20A, 20B, and 20C are joined and fixed to the support frame plate 70B at one end (end face 21) with high positional accuracy and squareness accuracy. The helical gears 71 to 73, which are rotatably supported by each, also rotate in an accurate position and in an accurate posture.

  In this drive transmission device 7, all of the three rotary shafts 20A, 20B, 20C are joined and fixed by welding to a support frame plate 70B having one end (end surface 21) formed with a through hole. Only a part of the rotating shafts may be fixed by such bonding.

  In addition, the drive transmission device 7 is a rotating body that transmits rotational power, and uses other types of rotating bodies such as a gear other than a helical gear and a roll that supports a belt for rotation transmission. Even in such a case, it is preferable to employ a joining structure portion that performs joining and fixing as described above for a rotating shaft that rotatably supports other rotating bodies such as gears and rolls.

  Further, the drive transmission device 7 can also be used as a device for transmitting rotational power for rotating a rotating object other than the photosensitive member 52.

  In addition, in the second embodiment, the image forming apparatus 1 is exemplified as a type (printer) that forms a single color toner image. However, the image forming apparatus is configured to display a color image composed of a plurality of toner images. It may be an image forming apparatus typified by a printer of the type to be formed, a copier, a factory, etc. Further, as a method for forming a toner image and transferring it to the paper 9, another conventionally known method (for example, an intermediate transfer method) can be employed. Further, the image forming apparatus 1 is not limited to a system that forms a toner image, and may be an image forming apparatus that employs another image forming system, for example, an image forming apparatus that employs an inkjet system.

It is a schematic sectional drawing which shows the outline | summary of the joining structure and gear support apparatus which concern on Embodiment 1. FIG. It is explanatory drawing which shows a state when the junction part of the structure of FIG. 1 and an apparatus is seen from the sheet metal side. It is a schematic cross-sectional explanatory drawing which shows the manufacturing process and instrument of the joining structure of FIG. FIG. 4 is a schematic cross-sectional explanatory view showing a state during the welding operation of FIG. 3. It is explanatory drawing which shows the other structural example (state when it sees from the sheet metal side) of the through-hole formed in a sheet metal. It is a schematic sectional drawing which shows the other structural example of the rotating shaft to join and fix. It is a schematic sectional explanatory drawing which shows an example (principal part) of the joining structure which does not employ | adopt the structure of this invention. It is a schematic sectional explanatory drawing which shows the other example (main part) of the joining structure which does not employ | adopt the structure of this invention. FIG. 6 is an explanatory diagram showing an outline of an image forming apparatus according to a second embodiment (adopting a joining structure or the like). It is a top view which shows the drive transmission apparatus employ | adopted with the image forming apparatus of FIG. It is principal part schematic sectional drawing which shows the structure of the joining fixation of a rotating shaft, etc. in the drive transmission device of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Joining structure, 4 ... Gear support apparatus (rotary body support apparatus), 5 ... Image forming apparatus, 7 ... Drive transmission apparatus, 10 ... Sheet metal (plate-shaped member), 12 ... Surface part including a through-hole, 15, DESCRIPTION OF SYMBOLS 16 ... Through-hole, 20, 20A, 20B, 20C ... Rotating shaft (bar-shaped member), 21 ... End surface, 30, 31-33 ... Welded part, 40 ... Gear (rotating body), 70B ... Support frame board (plate-like member) ), 71 to 73... Helical gear (rotary body).

Claims (6)

A plate-like member in which a through-hole for welding is formed;
A portion of the surface including the through-hole of the plate-like member has a rod-like member whose end face is contacted and fixed by welding,
While forming the through hole of the plate-shaped member so as to be located in an opening area narrower than the area of the end surface of the rod-shaped member and in the substantially central portion of the end surface,
At least a part of the through hole of the plate-like member and at least a part of the end face of the rod-like member are welded.   The joint structure according to claim 1, wherein the through hole of the plate-like member is formed with an opening area in which the entire circumference of the through hole is welded by one welding operation.   The joined structure according to claim 1, wherein the rod-shaped member has a straight rod shape. The rod-shaped member is a rotating shaft that rotatably supports a rotating body, including the joined structure according to any one of claims 1 to 3,
A rotating body support device, characterized in that a rotating body is supported on the rotating shaft.   The joining structure according to any one of claims 1 to 3, wherein at least one part of a joining structure part that joins and fixes a rotating shaft of a rod-like member that rotatably supports a rotating body used for transmission of rotational power to a plate-like member. A drive transmission device characterized in that the drive transmission device is constituted by a thing.   An image forming apparatus, wherein at least a part of a drive transmission device for transmitting rotational power is constituted by the drive transmission device according to claim 5.

Images