JPH0733262Y2 - Drum support device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a drum support device having both ends supported by bearings.

(Prior Art) As an example of such a drum supporting device, a photosensitive member supporting device in an electrophotographic copying machine will be described. In this case, the photoconductor is formed in a drum shape, and the surface is vapor-deposited with a photoconductor such as selenium, but its characteristics deteriorate with the number of times of use, so it is required to replace it after a predetermined number of times of use. It That is, in FIG. 3, the photoconductor 1 is sandwiched by the flange 4 (only one side is shown) fixed to the photoconductor shaft 2 via the screw 3. The shaft end 2a is supported by a bearing 5 such as a ball bearing,
Is held by a bearing box 8 fixed to the side plate 6 with screws 7. An extensible spring 9 is elastically mounted between the flange 4 on one side and the bearing 5 on the same side, and the photoconductor 1 is pressed to the left in the plan view to prevent axial shake. . Therefore, in order to remove the photoconductor 1, all the screws 7 must be removed and the bearing box 8 must be isolated to the right in the figure, and when the photoconductor 1 is mounted, the spring 9 has a strong elastic force. In order to screw the screw 7 to the side plate 6, it is necessary to strongly push the bearing box 8 to the left in the figure, which requires a great deal of time and labor.

(Purpose) An object of the present invention is to provide a drum supporting device that allows easy removal and mounting of a drum.

(Structure) Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings.

In FIG. 1, reference numerals 10 and 11 denote side plates of the main body of the copying machine, which are arranged to face each other. The photosensitive member 1 as a drum is rotatably supported between the side plates 10 and 11,
As in the prior art, the photosensitive member shaft 12 as a driven shaft is fixed via the flange 4. A small diameter portion 12a, which is a fitting shaft portion, is formed at one end portion of the photoconductor shaft 12, for example, the left end portion in the drawing, and a pin 16 that is an engaging portion penetrates and is fixed to the small diameter portion 12a in a direction orthogonal to the axial direction. It has been planted. On the other hand, the photoconductor shaft 12
A small-diameter portion 12b is also formed at the other end of the, and the boundary between the large-diameter portion and the small-diameter portion forms a stepped portion 12c that is an abutting portion so that the bearing supports the small-diameter portion 12b. There is.

A first bearing box 13 is fixed to the first side plate 10 with screws 30. Ball bearings 14 and 15, for example, are forcibly fitted into the bearing box 13 from both sides, and an impact is provided in the center. Plywood 13
It is positioned by a. Reference numeral 19 denotes a pulley, which transmits a driving force from a driving source (not shown) to the driving shaft 17. Drive shaft 17 is a bearing
The pulleys 19 and 14 are fitted and integrated with the pulley 19 via a key (not shown). Further, the end portion 17a of the drive shaft 17 of the photosensitive member 1 is formed in a flange shape, and further engages with the pin 16 of the photosensitive member shaft in which a groove 17b as an engaged portion is formed in a direction orthogonal to the axial direction. A non-permeable hole 17c, which is a fitting insertion hole, is formed in the center of the photoconductor shaft so that the small diameter portion 12a of the photoconductor shaft can be fitted therein. That is, since the bearings 14 and 15 are arranged at positions immovable with respect to the first side plate 10, the bearings 14 and 15 are called immobile first bearings, and the photoconductor shaft 12 is the drive shaft supported by the first bearings. With respect to 17, the shaft center is kept the same by inserting the small diameter portion 12a and the impermeable hole 17c, and the driving force is transmitted by the engagement of the pin 16 and the groove 17b.

On the other hand, the second side plate 11 has a cylindrical sleeve with a flange.
20 is fixed via screws 31. A sleeve screw 20a is formed on the outer peripheral portion of the sleeve 20, the inner peripheral portion of the sleeve 20 holds the bearing box 22 movably, and a small diameter portion 20c is provided at one end to prevent the bearing box 22 from falling off. Has been formed. The bearing box 22 is formed in the shape of a stepped cup in which the photoreceptor 1 is open, and a second bearing, for example, a ball bearing 23 is forcibly fitted into the opening, and the stepped portion 22a is an outer ring portion of the bearing 23. It is designed to be struck by. The bearing 23 is fitted and inserted so that the photoconductor shaft small-diameter portion 12b can be inserted and removed. A screw 24 is screwed on the bottom of the bearing box 22. The cap nut 25, which is a cap-shaped biasing release means that is screwed into the sleeve screw 20a, has an outer peripheral portion, for example, knurled, which makes it easy to rotate by hand, and is transparent at the center. A hole 25a is formed. The connecting shaft 26 is for connecting the cap nut 25 and the bearing box 22, and at one end thereof, a screw that engages with the bearing box screw 24 and a spanner when engaging with the screw 24 are engaged. Spanner hook 26a
Is formed, the other end is loosely inserted through the cap nut through hole 25a, and a retaining ring 27 is provided between the cap nut 25 and the clip 28 so that the connecting shaft 26 moves when the cap nut 25 is loosened. It is installed. Coil spring 29 as a pressurizing means
Is wound between the spanner 26a and the cap nut 25 while winding around the connecting shaft 26, and the bearing is inserted via the bearing box 22.
The first plain bearings (14, 15) are urged to the direction 23 close to the crocodile. Therefore, the cap nut functions as a bias release means depending on the direction of rotation. This drawing shows a usable state of the photoconductor, in which the connecting shaft 26 is completely screwed to the bearing box screw 24 and the cap nut 25 is completely screwed to the sleeve screw 20a. Therefore, the pressing force of the coil spring 29 is transmitted from the bearing box step portion 22a to the outer ring portion of the bearing 23 and from the inner ring portion of the bearing 23 to the photoconductor shaft step portion 12c, and the photoconductor shaft end portion (1
2a) abuts the bottom surface of the drive shaft impermeable hole 17c and urges the drive shaft 17 in a direction to move leftward in the drawing. The transmission force to the drive shaft 17 acts on the bearing box abutment wall 13a via the bearing 14.
At this time, the photoconductor shaft pin 16 is engaged with the drive shaft groove 17b, and a gap G is formed between the top surface of the cap nut 25 and the retaining ring 27.
Is essential to exist.

Next, FIG. 2 shows a state in which the photoconductor is exchanged. First, when the cap nut 2 is rotated in the loosening direction and completely detached from the sleeve 20, the connecting shaft 26 passes through the retaining ring 27. By moving together with the cap nut 25, the bearing box 22 can be pulled out from the small-diameter portion 12b of the photoconductor shaft while the bearing 23 is fitted.
Further, the position where the cap nut 25 is moved to the right in the figure and the bearing box 22 abuts the sleeve small diameter portion 20b is shown in this figure. At this time, since the photoconductor shaft 12 is held in a state where the left end in the drawing (not shown) is fitted in the drive shaft impermeable hole 17c, hold the photoconductor 1 in hand and move it to the right in the drawing. The photosensitive member can be detached from the main body of the copying machine by moving it to pull out the end portion from the impermeable hole, and further inclining the whole portion to pass between the side plates 10 and 11.

In the above description, the coil spring is exemplified as the pressurizing means, but cylindrical rubber or the like may be used, and the impermeable hole, the small diameter portion, and the small diameter portion may be used as the fitting and engaging mechanism between the driving shaft and the driven shaft. Although an example in which the groove and the pin are used is shown, it may be replaced with a spline engagement structure. Further, it goes without saying that the drum is not limited to the photoconductor and may be any drum that needs replacement.

(Effect) As is apparent from the above description, the present invention tightens the cap nut because the cap nut and the sleeve as the urging release means are screwed to urge or release the pressing means. The pressurizing means can be urged only by loosening the cap nut, and the pressurizing means can be opened simply by loosening the cap nut.When mounting the drum on the main body, the force of the drum is not required to be stronger than the repulsive force of the pressurizing means. Since the second bearing is detached from the sleeve because it can be easily attached and detached, a small diameter portion is formed in the sleeve as a detachment prevention means, and the second bearing and the bias release means are connected via the pressurizing means. The workability is excellent and the drum can be detached or mounted very easily without using a special tool.

[Brief description of drawings]

FIG. 1 is a partially broken sectional view showing an embodiment of the present invention, and FIG.
FIG. 3 is a partially exploded cross-sectional view for explaining a procedure for pulling out the second bearing from the photoconductor shaft in order to remove the photoconductor, and FIG. 3 is a cross-sectional view showing only a main part of one conventional example of the drum supporting device. . 1 ... Drum drum photoconductor, 12 ... Driving shaft photoconductor shaft, 12a ... Small diameter part that is a fitting insertion part, 12b ... Abutting step part, 14,15 ... First bearing ball Bearing, 16 ...
... Pins that are engaging parts, 17 ... Drive shaft, 17b ... Grooves that are engaged parts, 17c ... Impermeable holes that are insertion holes, 20 ... Sleeves, 23
...... The second bearing is a ball bearing, 25 is a cap nut that is an urging release means, and 29 is a coil spring that is a pressurizing means.

Claims (1)

[Scope of utility model registration request] 1. A device for supporting a drum between a pair of side plates, comprising: a first bearing fixed to one side plate; and a first bearing rotatably supported by the first bearing and a fitting insertion hole and a cover. A drive shaft having an engaging portion formed therein; a second bearing that forms a pair with the first bearing; and a side plate that is fixed to the other side plate, and the second bearing is disposed inside thereof so as to be movable in the axial direction. Inside the sleeve, the sleeve, in which the drop-out preventing means of the second bearing is formed on a part of the inner peripheral surface, the cap-shaped biasing opening means screwed to the outer end of the sleeve, And a pressurizing unit that is disposed between the second bearing and the biasing opening unit and that can bias the second bearing toward the first bearing; A shaft portion and an engaging portion that engages with the engaged portion are formed at one end portion, and the other end portion is turned to the second bearing. A drum supporting device which is rotatably supported and has a driven shaft on which the drum is fixedly mounted.