JPS6375779A - Meandering preventive mechanism for endless belt - Google Patents

Abstract

PURPOSE:To prevent a belt from meandering and to stabilize its running by a simple structure, by providing integrally a guide part projecting to the inside, in a position apart from the side end of an endless belt, and providing a guide groove in a corresponding position on the peripheral surface of a roller. CONSTITUTION:A guiding part 14 is projected and provided integrally on the position of the inside from the side end 13 of an endless belt 12 which is wound to a roller 11 and runs, and in the position of the roller 11 corresponding to said part, a ring-shaped guiding groove 15 is provided. When the belt 12 runs, the belt receives the pressing force of P1 and P2 in the right and left of the guiding part, therefore, the guiding part does not run on the peripheral surface of the roller but can run stably.

Description

[Detailed Description of the Invention] [Summary] The present invention is aimed at preventing meandering of endless belts such as recording belts used in electrostatic back recording type printers and display devices. A convex guide portion is provided at a position away from the side edge of the
This objective is achieved by fitting the endless belt onto the rollers that are passed around it.

It is.

The recording belt used in electrostatic back recording type printers and display devices is an endless belt made of a thin dielectric film. plays the role of transporting the toner image formed on the recording belt to be transferred to a medium such as paper.

This type of endless belt is made of a wide and thin film, so when it runs, a component of force in the direction perpendicular to the running direction is generated due to errors in left and right lengths, variations in tension, etc., resulting in so-called meandering. do. Therefore, preventing this meandering becomes an important issue.

[Conventional technology]

FIG. 5 is a perspective view showing a conventional endless belt meandering control mechanism. In the figure, 1 is a feed roller, 2.3 is a guide roller, and 4 is a film-like recording belt (endless belt).

The recording belt 4 is driven by a feed roller 1 driven by a drive source (not shown) via a feed gear 5, and is applied with a transporting force to run. Reference numeral 6 denotes a meandering control mechanism for controlling the meandering of the recording belt 4, which includes a meandering control lever 7, a pressing member 8 connected to the meandering control lever 7, a magnet (not shown), and a pair of left and right ends of the belt (not shown). It consists of a detection sensor. Reference numeral 9 denotes a tension spring that applies tension to the recording belt 4. The meandering control lever 7 is biased in the direction of arrow A by an activated magnet, and the pressing member 8 presses one end of the guide roller 3 downward. In this state, the tension of the recording belt 4 at the pressed portion increases, so the recording belt 4 tends to move toward the meandering control lever 7 side. When the recording belt 4 shifts toward the lever side by a predetermined amount, one sensor on the lever side detects this.

When the meandering control lever 7 is pulled and rotated by a predetermined amount in the direction of arrow B, the tension of the recording belt 4 at the pressed portion decreases, and the recording belt 4 moves toward the opposite side.

This pulling of the meandering control lever 7 is achieved, for example, by providing another magnet and activating this magnet, and continues until the other sensor detects the deviation of the recording belt 4. When another sensor detects this shift, the other magnet stops operating and returns to its initial operation, and the meandering control lever τ7 again rotates in the direction of the arrow. Thereafter, meandering control of the recording belt 4 is performed by repeating this operation.

[Problem that the invention seeks to solve]

However, such conventional mechanisms have the drawbacks of complicated structures and high costs.

[Means for solving problems]

The present invention provides a meandering prevention mechanism for an endless belt that can solve the above-mentioned problems, and the principle thereof is shown in FIG. In the figure, 11 is a roller, and 12 is an endless belt that is wound around the roller 11 and runs.

The endless bell l-12 is integrally provided with a guide portion 14 that projects inward at a position away from the side end 13. The guide portion 14 may be formed integrally with the belt main body, or may be formed by attaching a separate member to the belt main body.

Further, the roller 11 is formed with a ring-shaped guide groove 15 into which the guide portion 14 is fitted.

[Effect]

Since the guide portion 14 is formed at a position apart from the side end 13, the endless belt 12 is pressed against the roller 11 with forces PI and P2 on the left and right sides of the guide portion 14 due to its tension. Therefore, due to this pressure contact force, the endless belt 12 continues to run in the illustrated state, and the guide portion 14 does not ride on the circumferential surface of the roller, thereby preventing meandering.

〔Example〕

The present invention will now be described in detail with reference to FIGS. 2 to 4.

Fig. 2 is a front view showing an outline of an electrostatic printer to which the present invention is applied, and Fig. 3 is a perspective view showing the structure of the main parts of the electrostatic printer. is a recording belt (endless belt). These members are the first
Similar to the one shown in the figure, the feed roller 11 is formed with a ring-shaped guide groove 15, and the recording belt 12 is formed with a guide portion 14. The guide portion 14 is provided to protrude inward at a position away from the side end 13 of the recording belt 12, and the guide groove is provided at a position corresponding to this guide portion 14. 31 is a recording electrode, 32
33 is a fixing device, and 34A and 34B are corona static eliminators. Further, 35 is a transfer roller.

The recording belt 12 has a dielectric film as a base material and has a concavo-convex layer on the electrode side to ensure a gap. The feed roller 11 driven by the motor 47 applies a feeding force to travel in the direction of the arrow.The guide rollers 36, 37A, 37B also have a ring-shaped guide groove 15 similar to the ring-shaped guide groove 15. Of course, a ring-shaped guide groove is formed.The recording electrode 31 and the magnetic toner developing device 32 are formed by a guide roller 37A.

37B, they face each other with the recording belt 12 in between. The recording electrode 31 has a multi-stylus configuration in which a plurality of groups of electrode needles 39 are arranged in a line in a direction perpendicular to the paper plane of FIG. The magnetic toner developing device 32 is provided with a rotating magnetic roller 41 inside a fixed cylindrical sleeve 40, and a magnetic roller 41 that is divided into a plurality of segments on the cylindrical sleeve 40 in a direction perpendicular to the paper plane of FIG. A counter electrode 42 is provided. The counter electrode 42 is located in the recording section 38 and is connected to the recording electrode 31.
is facing.

When recording with an electrostatic printer having such a configuration, magnetic toner 43 is transferred to the outer periphery of the cylindrical sleeve 40 by a transfer roller (not shown), and a voltage corresponding to an image signal is applied to the electrode needle 39. By selectively applying a voltage of opposite polarity to the counter electrode 42, magnetic toner is attached to the recording belt 12 running in contact with the recording electrode 31 to form a toner image. In this way, the recording belt 12
The toner image formed thereon is transferred to a transfer roller 3 at a transfer section 44 along the recording belt 12 as shown in FIG.
5 onto the paper (medium) 100. The transferred toner image is fixed by the fixing device 33 in the fixing section 45, and recording is completed.

After the transfer, the charge of the residual magnetic toner is removed from the recording belt 12 by the charge eliminating section 46. In this case, corona static eliminators 34A and 34 placed across the recording belt 12
Alternating voltages having different phases are applied to B, thereby erasing the charge of the residual magnetic toner and discharging the recording belt 1.
The adhesion force of the magnetic toner to 2 is weakened. When the recording belt 12 further travels and reaches the recording section 38, the remaining magnetic toner is transferred to the magnetic roller 41 in the magnetic toner developing device 32.
is collected by the magnetic force of

During these processes, the recording belt 12 moves along the guide section 1.
4 runs stably while being guided by the ring-shaped guide groove of each roller.

By the way, when the guide section 14 is provided at the side end of the recording belt 12, it is generally impossible to completely match the depth of the ring-shaped guide groove and the height of the guide section.
For example, as shown in FIG. 4(a), the guide groove 16 is formed deeper than the height of the guide portion 14. However, in this case, as the recording belt 12 continues to meander, a component force P3 is generated that causes the guide portion 14 to climb up from the guide groove 16 onto the roller circumferential surface, as shown in FIG. Part 1
4 crosses the guide groove 16 and approaches the inside.

However, in the present invention, the guide section 14 is connected to the recording belt 12.
Since it is formed at a position away from the side edge 13 of the
As described above with reference to the drawings, the recording belt 12 is pressed against the rollers on the left and right sides of the guide portion 14 by forces P, . . . P2 due to its tension. Therefore, due to this pressure contact force, the guide portion 14 of the recording belt 12 is guided by the guide groove 15 and continues to run stably, thereby preventing meandering.

The present invention is applicable not only to the electrostatic recording belt of the embodiment, but also to photoreceptor belts, transfer belts, and the like.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to achieve the following various excellent effects.

(1) Meandering of a wide and thin endless belt can be prevented.

(2) Machining of the guide portion and the guide groove does not require high precision, and also does not require a complicated mechanism like the conventional ones, so costs can be reduced.

(3) The recording belt runs stably and is highly reliable.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the principle of the present invention, Fig. 2 is a front view showing an overview of an electrostatic printer according to an embodiment of the invention, Fig. 3 is a perspective view showing the main parts of the electrostatic printer, and Fig. 4 (
a) and (b) are comparative diagrams for explaining the same effect, and Fig. 5 is a perspective view showing a conventional meandering control mechanism of an endless belt. ), 13 is a side edge of the recording belt, 14 is a guide portion, 15 is a ring-shaped guide groove, 36. 37A and 37B are guide rollers (rollers).

Claims (1)

[Claims] An endless belt (
12) is integrally provided with a guide portion (14) projecting inward at a position away from the side end (13), and a ring-shaped guide groove into which the guide member fits is formed in the roller. Features an endless belt meandering prevention mechanism.