JPS6233585B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for attaching and detaching a sheet-like photoreceptor. The present invention relates to a sheet-like photoreceptor attachment/detachment device that is useful when attached to a sheet-like photoconductor attachment/detachment device for attaching or releasing the sheet.

In an electrophotographic copying machine, which is one of the potential implementation targets of the present invention, two typical types of photosensitive materials are known as so-called photoreceptors, selenium-based and zinc oxide-based. Although these materials have excellent photoconductivity, dielectric properties, etc., and can be used repeatedly in many image forming steps, they are extremely expensive. On the other hand, the latter type of zinc oxide type is considerably cheaper than the selenium type, and its life span has been improved in recent years. Therefore, if such a zinc oxide-based photoreceptor is used, the cost of the copying machine or the cost of copying can be reduced. However, compared to selenium-based photoreceptors, zinc oxide-based photoreceptors still have
The situation is such that replacement frequency has to increase due to the longevity. In particular, for copying machines that use a type of photoreceptor drum in which a sheet-like photoreceptor is wrapped around the drum, the sheet-like photoreceptor wrapped around the drum must be removed each time the photoreceptor reaches the end of its life. It is necessary to remove it and attach a new photoreceptor to the drum circumference.

In order to meet this need, the peripheral surface of the photoreceptor drum is equipped with a sheet attaching/detaching device for gripping and releasing the end portion of the sheet-like photoreceptor from the drum peripheral surface. FIGS. 1 and 2 show an extracted portion of the sheet gripping and releasing mechanism of this sheet attaching/detaching device, which is closely related to the present invention.

Hereinafter, technical problems to be solved regarding the sheet gripping and releasing mechanism will be described to the extent necessary for understanding the present invention.

FIG. 1 shows a sheet-like photoreceptor S (hereinafter simply referred to as "sheet S") attached to a cylindrical photoreceptor drum D ₀
(hereinafter simply referred to as "drum D ₀ "), and one end Sa of the claw 2 is wound on the slope 1a of the groove 1 carved in a V-shape on the longitudinal circumferential surface of the drum D ₀ . It shows a state in which it is being held by being pressed by. In this configuration, as the pawl 2 moves up and down in the radial direction of the drum _D0 , one end of the sheet S is
Sa is grasped or released. This nail 2
FIG. 2 shows a mechanism for moving the as described above.

In the figure, numerals 3 and 4 both indicate levers formed of keyhole-shaped plate pieces, and their base end 3
a, 4a are fitted onto the shaft 5 which is integrated with the drum _D0 ,
They are located near the outer sides of the side walls D ₁₀ and D ₂₀ of the drum D ₀ . And the extending portions 3b of the levers 3, 4,
Guide pins 6, 7 and 8, 9 are implanted in 4b, respectively. The levers 3 and 4 are connected to the U-shaped connecting member 1 so as to maintain positions facing each other.
Connected by 0. A long hole 11 bored in a sliding plate 11 formed at one base end of the connecting member 10
Guide pins 6 and 7 are inserted through a and 11b, and a guide pin 8 is inserted into an elongated hole (not shown, but similar to the elongated holes 11a and 11b) drilled in the sliding plate 12 at the other base end. _. ,7,
It is locked at 8 and 9.

Pins 14 and 15 are embedded in the sliding plates 11 and 12, respectively, so as to pass through them and run parallel to the longitudinal direction of the drum _D0 . Also, pin 1 is attached to levers 3 and 4 respectively.
6 and 17 are planted, pin 14 and pin 16
A compressible spring 18 is placed between the pins 15 and 17, and a compressible spring 19 is placed between the pins 15 and 17 as well. Due to the action of these springs 18 and 19, the connecting member 10 has a tendency to move toward the center of the drum _D0 , and this movement causes the pins 14 and 15 to move toward the circumferential surface or groove of the drum _D0 . It is restrained by pressing against the bottom of 1.

In the connecting member 10, the bridging portion 13, which is a long strip-shaped portion that extends in the longitudinal direction of the drum _D0 and integrally connects the sliding plates 11 and 12, has a surface facing the drum _D0 . The claw 2 shown in the figure is formed.

Now, when gripping the sheet S, after inserting one end Sa of the sheet S to be gripped into the groove 1,
By applying an external force, the pins 14 and 15 are slid onto the circumferential surface of the drum _D0 , and are inserted into the bottom of the groove 1.
In other words, the pins 14, 15 are pulled by the springs 18, 19 along the slopes 1a, 1b, descend to a position where the claw 2 presses one end of Sa, and stop at that position. In this way, one end Sa is gripped (see Figure 1).

Note that the other end Sb is held by means separate from the above, but this will not be discussed because it has no important meaning in understanding the present invention. drum
D ₀ is rotated clockwise when gripping and releasing the sheet S. When releasing the grip on one end Sa, the stop pin 20 is moved in the direction of the arrow by a stop pin moving mechanism (not shown) on the rotation locus of the lever ₃ , which rotates clockwise together with the drum D0 in the grip state.

In other words, the stop pin 20 is brought out at a time when it is desired to release the grip of the sheet S by the claws 2, and prevents the lever 3 from rotating. Even if the lever 3 is prevented from rotating in this way, the lever 3 and the shaft 5 are loosely fitted, so the drum D ₀ can further rotate together with the shaft 5 in the clockwise direction. The lever 3 is thus locked and the lever 4 is substantially locked via the bridge portion 13.
The slopes 1a, 1b move relative to each other, so that the pins 14, 15 climb up the slopes 1a, 1b against the tension force of the springs 18, 19. That is, the pawl 2 moves together with the pins 14 and 15 relatively in the radial direction of the drum D ₀ in a direction away from the rotation center of the drum D ₀ and releases its grip on Sa at one end.

By the way, in order for such an action to be performed smoothly, in addition to the stop pin 20 that prevents the lever 3 from rotating, a stop pin 21 that is provided at a position facing the stop pin 20 and prevents the lever 4 from rotating is required. It is desirable to have a If the stop pin 21 is not used,
This is because when releasing Sa, there is a risk that excessive force will be applied to the bridge portion 13 of the connecting member 10 and it will be twisted. If the stop pin 21 is not provided, the force to prevent the rotation of the lever 4, that is, the force required for the pin 15 to climb the slope 1b, is as follows: lever 3 → guide pins 6, 7 → sliding plate 11 → bridge part 13
→ The force is transmitted to the sliding plate 12 → the pin 15, and the bridge portion 13 becomes unable to support the force required for the pin 15 to climb the slope 1b, and the lever 4 becomes more clockwise than the lever 3. This is because the bridging portion 13 is bent and twisted as it advances in the direction, and as a result, the claws 2 become misaligned, making it impossible to grip them thereafter.

However, in order to provide the stop pin 21 other than the stop pin 20, it is necessary to also provide ancillary equipment such as a pin drive mechanism that combines a solenoid and a cam to move the stop pin 21 to a predetermined position and to retract it. Copying machines with limited physical space are physically difficult, and the mechanism is complicated, resulting in high costs.

SUMMARY OF THE INVENTION An object of the present invention is to provide an improved sheet-like photoreceptor attachment/detachment device, and more specifically, a sheet-like photoreceptor attachment/detachment device that solves the above-mentioned dilemma, that is, a sheet-like photoreceptor attachment/detachment device that rotates together with the drum _D0 . One of the levers 3 and 4, for example, a stop pin 20 for locking the lever 3.
As long as the stop pin 21 and its ancillary devices are provided, the lever 4 can be moved without applying any torsional moment to the bridge portion 13, without having to take other measures such as providing the stop pin 21 and its ancillary devices at the opposing position.
An object of the present invention is to provide a sheet-like photoreceptor attachment/detachment device that can obtain the same effect as when the lever 3 is locked at the same position as the lever 3.

Embodiments of the present invention will be described below based on the drawings.

FIG. 3 illustrates the invention in principle. In the figure, reference numeral D indicates a cylindrical drum, and a shaft 21 is fixedly supported through both side walls D ₁ and D ₂ of the drum.
Sun gears S ₁ and S ₂ are installed near the outer sides of the side walls D ₁ and D ₂ .
and levers 22, 23 integrated with each sun gear S ₁ , S ₂
is automatically fitted onto the shaft 21 and is prevented from coming off by known means so as not to shift in the longitudinal direction of the shaft. Further, a support shaft 2 is provided on the side walls D ₁ and D ₂ at a certain distance from the shaft 21 penetration part.
4 is passing through.

The support 24 extends between the side walls D ₁ and D ₂ and is rotatably supported by the side walls D ₁ and D ₂ . Furthermore, planetary gears P ₁ and P ₂ are fixed to the support shaft 24, and these planetary gears P ₁ and P ₂ mesh with the respective sun gears S ₁ and S ₂ . Here, sun gear S ₁ and
S ₂ has the same number of teeth, and the planetary gears P ₁ and P ₂ have the same number of teeth.

Now, the lever 22 is locked by the stop pin 25. In this state, the positions relatively occupied by each member shown in FIG. 3 are defined as the original positions of each member.

(1) Now, assume that the drum D is rotated clockwise by a degree from its original position with the axis Y-Y of the shaft 21 as the center of rotation. This means that drum D and lever 2
2, it is equivalent to rotating the lever 22 counterclockwise by a degree with respect to the drum D. Hereinafter, the actions of each member activated as a result of rotating the drum D clockwise by a degree from its original position will be described.

(2) As the drum D rotates a degree clockwise from its original position, the axial center of the shaft 24 naturally moves a degree clockwise around the axis Y-Y. At this time, the planetary gear P ₁ rotates clockwise around the sun gear S ₁ by a movement corresponding to the rotation angle a°. Here, the number of teeth of the planetary gear P ₁ that has moved on the sun gear S ₁ while meshing with the sun gear S ₁ during the above-mentioned rotation and revolution is assumed to be δ. Then,
This means that the planetary gear P ₁ rotates clockwise by δ gears while meshing with the sun gear S ₁ . This means that
If the sun gear S ₁ is rotated by an amount of δ with the number of teeth, this means that the sun gear S ₁ is rotated by an amount corresponding to a degree when this is converted into an angle.

(3) On the side wall D ₁ side, as a result of the operation in (1) above, the planet gear P ₁ functions as a driven gear with respect to the sun gear S ₁ , and on the side wall D ₂ side, the planet gear P ₁ functions as a driven gear with respect to the sun gear S 1. The integral planetary gear P ₂ acts as a driving gear for the sun gear S ₂ . The planetary gear _P1 and the planetary gear _P2 are substantially integral. Therefore, the planetary gear P ₂ moves exactly the same as the planetary gear P _{1 with respect to the common reference of both planetary gears P 1 and} P ₂ , for example, the drum D, and the operation described in (1) above, that is, the lever 2
2 is locked by the stop pin 25, and the drum D is rotated a degree clockwise from the original position. As a result, the sun gear S ₂ becomes the planetary gear P ₂
This means that it has been rotated counterclockwise by δ sheets from the original position. The sun gear _S2 and the lever 23 integral therewith are rotated a degree counterclockwise relative to the drum D.

(4) Therefore, considering what was stated in the latter part of (1) above, both the lever 22 and the lever 23 are a
゜This means it has rotated counterclockwise.

As described in (1) to (4) above, in the present invention, the relative movement of the lever 22 with respect to the drum D is as follows: lever 22 → sun gear S ₁ → planet gear P ₁ → support shaft 24 → planet gear P ₂ → The sun gear S ₂ is transmitted to the lever 23 via the transmission path of the lever 23, and is transmitted to the drum D.
The angle of movement relative to the levers 22 and 23 is equal under the conditions that the number of teeth of the planetary gears P ₁ and P ₂ is equal, and the number of teeth of the sun gears S ₁ and S ₂ is equal.

By appropriately rearranging the gear ratios of the planetary gear P ₁ , sun gear S ₁ and planetary gear P ₂ , sun gear S _2, the lever 22 relative to the drum D can be adjusted.
The angle of movement of the lever 23 with respect to the drum D at that time can be made different.

Next, a sheet-like photoreceptor attachment/detachment device, which is an embodiment of the present invention, will be described. FIG. 4 shows an example in which the present invention described with reference to FIG. 3 is applied to the sheet gripping and releasing mechanism shown in FIGS. 1 and 2.

The configuration of the sheet gripping mechanism shown in FIG. 4 is based on the entire configuration of the sheet gripping mechanism shown in FIG. A shaft 21 and levers 22, 23 are mounted thereon, and mounting holes are drilled in the side walls D ₁₀ , D ₂₀ , and a support shaft 24 is rotatably mounted on each side wall D ₁₀ , D ₂₀ . In this state, the sun gears S ₁ and S ₂ are meshed with the planet gears P ₁ and P ₂ , respectively, and the planet gears P ₁ and P ₂ are each fixed to the support shaft 24. Also, in FIG. 2, lever 3,
By the same means as attaching the connecting member 10 to 4,
A connecting member 10 is attached to the levers 22 and 23.

Therefore, among the reference numerals given in Fig. 4, the members given the same reference numerals as those used in Figs. 1, 2, and 3 that have already been explained will be referred to as It shall have substantially the same shape, configuration, and function as described.

Now, the pin 14 and the pin 15 are respectively on the slope 1a,
1b, one lever 22
Suppose that it is locked with the stop pin 20. In this state, if the drum D ₀ is rotated a degree clockwise with respect to the lever 22, the pin 14 will rotate counterclockwise a degree relative to the drum D ₀ with the shaft 21 as the center of rotation.
This means that it has rotated by .degree., and begins to climb the slope 1a against the tensile force of the spring 18. A relative movement of the lever 22 in the counterclockwise direction a° with respect to the drum D ₀ simultaneously causes the rotation of the sun gear S ₁ →planet gear P ₁ →support shaft 24
→ Planetary gear P ₂ → Sun gear S ₂ → Lever 23 → The pin 15 is transmitted to the sliding plate 12, and the pin 15 is rotated a degree counterclockwise about the shaft 21 with respect to the drum D ₀ . The reason for this has already been described with reference to FIG.

Therefore, due to the action of the stop pin 20 provided on one of the two side walls D ₁₀ and D ₂₀ of the drum D ₀ , for example on the side wall D ₁₀ , the lever 22 locked by the stop pin 20 is moved. Drum D ₀
The relative movement to the lever 23 is transmitted to the lever 23 without passing through the bridge portion 13.

As described above, according to the present invention, as long as the lever 22 is locked by the stop pin provided only on one side of the drum D ₀ in FIG. This makes it possible to release the grip on the sheet S by separating the claw 2 from one end Sa (see FIG. 1).

That is, in addition to the stop pin 20, a stop pin for locking the lever 23 in a position opposite to the stop pin 20, such as the stop pin 21 shown in FIG. 2, is not necessary according to the present invention.

In other words, only one set of stop pin devices is required.
This can contribute to improving space efficiency. Therefore, the sheet gripping mechanism is simplified and costs are reduced.

The specific object of the invention as stated at the outset has thus been achieved.

Note that the above-mentioned examples are just a few embodiments of the present invention, and the principle of the present invention shown in FIG. 3 can be applied to device mechanisms similar to the device mechanism shown in FIG. It can be widely applied and implemented.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a sheet-shaped photoreceptor wrapped around the drum circumferential surface, one end of which is gripped by a claw in a groove carved in the drum circumferential surface;
The figure is a perspective view showing the structure of the device mechanism for moving the claw shown in Fig. 1, Fig. 3 is a perspective view showing the principle of the invention, and Fig. 4 is a perspective view showing an embodiment of the invention. It is. 22, 23...Lever, 24...Support shaft, D ₀
...Drum, D ₁₀ , D ₂₀ ... Side wall, S ₁ , S ₂ ... Sun gear, P ₁ , P ₂ ... Planet gear.

Claims (1)

[Scope of Claims] 1. A lever loosely fitted to a shaft integral with the drum in the vicinity of each side wall of the cylindrical drum, and a lever that is spanned between these levers and guided to each lever. a connecting member which is movable toward the center of the drum and has a habit of moving toward the center of the drum;
A groove is formed on the circumferential surface of the drum and can be freely engaged with a pawl that is integrated with the bridging portion of the connecting member, and a slope is formed at both longitudinal ends of the groove that protrudes from both end portions of the connecting member. It has a pin and a stop pin that stops the rotation of each lever that rotates with the drum, and uses the relative movement between the lever and the drum when the stop pin stops the rotation of the lever while the drum is rotating to move the pin along the slope. In a sheet attachment/detachment device, the sheet-like photoconductor is loosely fitted onto a shaft integrated with the drum. In addition, a sun gear is provided integrally with each lever, and a support shaft is rotatably inserted between both side walls of the drum.
A planetary gear is fixed to each end of this support shaft and meshes with a sun gear, respectively, and the gear ratio between the sun gear and the planetary gear on one side and the gear ratio between the sun gear and the planetary gear on the other side are determined. are the same, and the relative movement of this lever with respect to the drum due to the stoppage of rotation of the lever on one side at the drum rotation center is the sun gear on one side, the planetary gear, the support shaft, and the planetary gear on the other side. , a sheet-like photoreceptor attaching/detaching device characterized by transmitting information to the lever via the sun gear.