JPH03142450A - Pressure developing device - Google Patents

Abstract

PURPOSE:To uniformize and stabilize the pressing on a lower roller over the entire part thereof even if the outside diameter of pressing bodies vary by pressing the lower roller by the pressing bodies which are turnably supported at both ends of a tiltable supporting shaft. CONSTITUTION:Press rollers 3, 10 are turned in synchronization with the transportation of microcapsule paper formed with latent images and color developing paper to the pressure developing device and a cam shaft 4 is turned to move a lower plate 8 upward. The rollers 20 are then pressed from below via respective back up rollers 18 by the energizing force of a pressing spring 13, by which the two sheets of the paper are brought into pressurized contact with each other. Even if the outside diameters of a pair of the rollers 18 supported by the supporting shaft 17 vary, the roller 18A of the larger outside diameter comes into contact with the roller 10 first and further the shaft 17 is energized and tilts with the contact point between the roller 10 and the roller 18A as a fulcrum. The roller 18B of the smaller outside diameter comes into contact with the roller 10 as well and is energized by the sprint 13 to press the roller 10.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is capable of applying pressure to a transfer member based on a latent image on the photosensitive recording medium by pressing a photosensitive recording medium and a transfer member with a pair of rotatable rollers. The present invention relates to a pressure development device for forming an image thereon.

[Prior Art] Conventionally, this type of pressure developing device is provided with a pair of pressure rollers that press a photosensitive recording medium and a transfer member into contact with each other. A backup shaft is provided parallel to one of the pressure rollers, and backup rollers serving as a plurality of pressing bodies that press one of the pressure rollers from behind are rotatably inserted through this shaft. . Furthermore, a plurality of coil springs are arranged behind the backup shaft to correspond to each backup roller, and the biasing force of each spring biases each backup roller toward one of the pressure rollers via the backup shaft. At the same time, the biased rollers pressed one pressure roller against the other pressure roller.

[Problem to be Solved by the Invention] However, since each backup roller is inserted through the same backup shaft, if there is even a slight variation in the outer diameter of each roller, the distance from the center of the backup shaft to the outer periphery of each roller The lengths of the rollers did not match, and a roller with a smaller outer diameter than other rollers was sometimes not brought into contact with the pressure roller.

In such a state, even if each backup roller is urged by each coil spring via the backup shaft, the pressing force of each roller against the pressure roller will vary, and the pressure of one roller against the other pressure roller will vary. There is a problem in that the pressure force distribution of the roller becomes non-uniform, which tends to cause uneven development and wrinkles.

Furthermore, in the past, in order to prevent such problems, it was necessary to use expensive backup rollers with extremely high dimensional accuracy, which had the disadvantage of not being able to reduce costs.

The present invention has been made in view of the above circumstances, and its object is to provide a photosensitive recording medium with a uniform and stable pressing force over the entire roller without being affected by manufacturing errors of the pressing body that directly presses the roller. An object of the present invention is to provide a pressure developing device that can press a transfer member and a transfer member to form a beautiful image on the transfer member.

[Means for Solving the Problems] In order to solve the above problems, the pressure developing device of the present invention includes at least one support member disposed so as to be movable back and forth toward one of the rollers, and a support member located approximately at the center of the support member. a support shaft tiltably supported at the support shaft, a pressing body rotatably supported at both ends of the support shaft, and the pressing body is pressed toward one roller via the support member and the support shaft. , and biasing means for pressing one roller against the other roller by the pressure.

[Operation] As the biasing means biases the support member toward one of the rollers, the support shaft and the pressing bodies at both ends thereof are also biased in the same direction.
Both pressing bodies are brought into contact with one of the rollers. Here, even if one of the two pressing bodies comes into contact with the roller first, as the supporting member approaches the roller, the contact point between the one pressing body and the roller will change. The support shaft is tilted as a fulcrum, and the other pressing body is further moved toward the roller, and finally comes into contact with the roller.

Even after both pressing bodies come into contact with one of the rollers, both pressing bodies are pressed against the one roller by the urging means via the support member and the spindle, and the pressing causes one roller to move against the other roller. is pressed against.

[Embodiment] An embodiment in which the present invention is embodied in a pressure developing device of a color copying machine will be described below with reference to the drawings.

Regarding the entire structure of the color copying machine, please refer to the patent application 1986-16.
Please refer to Publication No. 8548 and the like.

As shown in FIG. 1, an upper pressure roller 3 is rotatably mounted on both side frames 2 of a main body 1 of the pressure developing device via a bearing 20. As shown in FIG.

Further, a camshaft 4 is rotatably installed on both side frames 2 via a bearing 5 in parallel with the upper pressure roller 3 . The camshaft 4 has support portions 4a each having a circular cross section formed at both ends thereof, an axis located eccentrically from the axes of the support portions 4a, and an eccentric connecting the support portions 4a. 4b, and is rotatably attached to each side frame 2 at both support portions 4a.

A pair of support plates 6 are provided inside both side frames 2.
are mounted so as to be movable up and down along the inner wall surface of each side frame 2, and both support plates 6 are connected at their lower ends by a lower plate 8 so as to be movable together. Each support plate 6 is fitted into the eccentric portion 4b of the camshaft 4 at its upper end. As the camshaft 4 rotates by a drive mechanism (not shown), the eccentric part 4b is moved up and down by an amount corresponding to the eccentric distance from the support part 4a, so that both the support plates 6 and the lower plate 8 are The arrangement is switched between an upper position shown in FIG. 2(a) and a lower position shown by a solid line in FIG. 2(b). Further, near the center of each support plate 6, a long hole 7 is provided through which the upper pressure roller 3 and its bearing 20 are inserted.
The upper pressure roller 3 and both bearings 20 prevent vertical movement of both support plates 6 from being restricted.

Oval-shaped guide holes 6a are transparently provided in each support plate 6 at positions below the elongated holes 7, and transparent holes 2a communicating with these guide holes 6a are provided at corresponding positions in both side plates 2. Each is transparent. Inside these holes 2a and 6a, a pair of substantially oval-shaped bearings 9 is provided so as to be movable up and down along the guide hole 6a, and a lower pressure roller 10 is mounted on both bearings 9. It is installed so that it can rotate. The lower pressure roller 10 has a pressure position where it contacts and presses the upper pressure roller 3 within the range of the guide hole 6a, and a pressure position where the lower pressure roller 10 contacts and presses the upper pressure roller 3.
The opening position is switched between the opening position and the opening position. The pressure rollers 3 and 10 are rotated synchronously by a drive motor (not shown), and when they are in pressure contact with each other, the microcapsule paper as a photosensitive recording medium and the color developing paper as a transfer medium are transported.

On the other hand, a plurality (four) of adjustment bolts 11 are screwed onto the lower plate 8 at predetermined intervals, and a spring receiver 12 is attached to the tip of each adjustment bolt 11, respectively. Each spring receiver 12 has a pressure spring 1 as a biasing means.
The lower ends of the pressure springs 13 are fixed to each other, and the pressure blocks 14 each having a support plate 16 projecting upward are fixed to the upper end of each pressure spring 13.

Each support plate 16 is provided with an insertion hole 16a, and a support shaft 17 having an outer diameter slightly smaller than the inner diameter of this hole is inserted into each of the insertion holes 16a. It is tiltably supported in 16 insertion holes 16a. In addition, each support shaft 17 has a thrust bearing provided in the main body 1 of the device, and its movement in the axial direction is restricted by a member (as shown). While engaged, it is tilted slightly in the vertical direction.

Further, the lower pressure roller 10 is provided at both ends of each support shaft 17.
A pair of backup rollers 18 as pressing bodies that come into contact with
are each rotatably supported. And a total of 8
two backup rollers 18, a support shaft 17, a support plate 16, a pressure block 14, a pressure spring 13. The lower pressure roller 10 and the pair of bearings 9 are elastically supported on the lower plate 8 via the spring receiver 12 and the adjustment bolt 11, and
When the lower plate 8 is placed in the upper position, the lower pressure roller 10 is pressed against the upper pressure roller 3 based on the urging force of each pressure spring 13.

The pressing force at this time can be adjusted by each adjusting bolt 11. Note that the pressure block 14 and the support plate 16 constitute a support member.

Next, the operation of the pressure developing device configured as described above will be explained.

In a standby state in which the copying operation of the color copying machine is temporarily stopped, the support plate 6 is placed at a lower position via the camshaft 4, as shown in FIG. 2(b). At this time, the lower pressure roller IO is moved downward against the elasticity of the pressure spring 13 and placed in the open position based on the engagement between its bearing 9 and the upper edge of the guide hole 6a of each support plate 6. , and the upper pressure roller 3 to form a predetermined gap. A long microcapsule paper (as shown) carrying a large number of microcapsules containing dye for color copying is inserted between the rain pressure rollers 3 and 10 in which the gap is formed. The color copying machine is prepared for transfer from the front side to the back side of the apparatus main body l by a large number of transfer rollers (as shown) provided in the color copying machine.

When a copying operation is started from this standby state, transport of the microcapsule paper on which a latent image has been formed by exposure is started. In addition, in synchronization with this, the developing paper (as shown) as a transfer member begins to be transferred between the rain pressure rollers 3 and 10 so that its leading edge coincides with the leading edge of the exposure area of the microcapsule paper.

At this time, the rain pressure roller 3. IO is synchronously rotated in the paper feeding direction. Then, the tip of the developer paper is
, 10, the camshaft 4 changes from the position shown in FIG. 2(b) to the position shown in FIG.
It is switched and rotated to the position shown in a). Accordingly, the support plate 6 is switched from the lower position to the upper position, and the upper edge of the guide hole 6a and the bearing 9 of the lower pressure roller 10
The upward movement restriction of the roller 10 based on the engagement with the roller 10 is released, and as the lower plate 8 moves upward, each member 1
1-18, the lower pressure roller 10 is switched to the pressure position.

In this way, the microcapsule paper and the color developer paper are sandwiched between the rain pressure rollers 3 and 10, and each backup roller 18 pushes up the lower pressure roller 10 from below based on the urging force of each pressure spring 13. As a result, the lower pressure roller 10 is pressed toward the upper pressure roller 3, so that the microcapsule paper and the color developer paper are pressed against each other by the two pressure rollers 3.10.

Here, as shown in FIG. 3(a), assume that the outer diameters of the pair of backup rollers 18 supported at both ends of the support shaft 17 are different due to manufacturing errors. In such a case, as shown in Figure 3(a),
When the support shaft 17 is biased toward the lower pressure roller 10 by the pressure spring 13, the roller 18A with the larger outer diameter first comes into contact with the lower pressure roller 10. As the support shaft 17 is further urged toward the pressure roller 10, as shown in FIG. 3(b), the support shaft 17 comes into contact with the lower pressure roller 10 and the roller 18A. A roller 18B with a small outer diameter, which is tilted in the insertion hole 16a using the contact point as a fulcrum and supported by the other end of the support shaft 17, is moved relatively upward and comes into contact with the lower pressure roller 10. In this way, the rollers 18A and 18B provided at both left and right ends of the support shaft 17 are both brought into contact with the lower pressure roller 10, and are urged by the pressure spring 13 to press the lower pressure roller 10 with an even pressing force. do.

In this way, a total of eight backup rollers 18 press the lower pressure roller 10 with uniform pressure over its entire length. Therefore, the microcapsule paper and the color developer paper are transferred from the front side to the back side of the apparatus body 1 as the Ryogawa pressure rollers 3 and 10 rotate, and the color developer paper is transferred over the entire surface by the Ryogawa pressure rollers 3 and 10. It is pressed against the exposed area of the microcapsule paper with uniform pressure, and a beautiful image is formed on the developer paper based on the latent image on the microcapsule paper.

When the rear end of the developer paper passes between the rain pressure rollers 3 and 10,
The camshaft 4 is returned to rotation, and both the support plates 6, the lower plate 8, and the members 11 to 18 provided on the lower plate 8 are moved down together, and the lower pressure roller 10 presses the upper pressure roller 3. is released, and based on the engagement between the upper edges of the guide holes 6a of both support plates 6 and the bearings 9, the lower pressure roller 10 is placed in the open position shown in FIG. is returned to the standby state again.

As described above, according to the present embodiment, a pair of adjacent backup rollers 18 that press the lower pressure roller IO are set as a set, and each pair is attached to both ends of each support shaft 17 that is supported in a tiltable manner. Because it is rotatably supported, even if there is a difference in outer diameter between the two backup rollers 18 of each support shaft 17 due to manufacturing errors, both rollers 18 are always evenly aligned with the lower pressure roller 10. Pressed by Therefore,
The lower pressure roller 10 presses the upper pressure roller 3 with a uniform pressure distribution without being affected by slight variations in the outer diameter of each backup roller 18. can be pressed against the roller with a uniform and stable pressing force over the entire length direction, and a beautiful image can be formed on the developing paper.

Further, according to this embodiment, there is no need to use an expensive backup roller with extremely high dimensional accuracy, so it is possible to reduce costs.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to press a photosensitive recording medium with a uniform and stable pressing force over the entire roller without being affected by manufacturing errors in the pressing body that directly presses the roller. It has the excellent effect of being able to come into pressure contact with the transfer body and forming a beautiful image on the transfer body.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of one embodiment embodying the present invention, Fig. 2 is a front sectional view of an embodiment embodying the present invention;
Figures (a) and (b) are cross-sectional views taken along line A-A in Figure 1, and Figure 3 (
a) and (b) are partially enlarged sectional views of FIG. 1; 3... Upper pressure roller, IO... Lower pressure roller,
13... Pressure spring as a biasing means, 14... Pressure block, 16... Support plate (the supporting member is constituted by the above 14.16) 17... Support shaft, 18...・Backup roller as a pressing body.

Claims (1)

[Claims] 1. An image is formed on the transfer body based on the latent image on the photosensitive recording medium by bringing the photosensitive recording medium and the transfer body into pressure contact with a pair of rotatable rollers (3, 10). In the pressure developing device, at least one support member (14, 16) is arranged to be movable back and forth toward one of the rollers (10), and the support member (14, 16) is tiltably supported approximately at the center. a supporting shaft (17), a pressing body (18) rotatably supported at both ends of the supporting shaft (17), and a pressing body (18) rotatably supported on both ends of the supporting shaft (17); It is characterized by comprising a biasing means (13) that presses the pressing body (18) toward one roller (10) and presses one roller (10) against the other roller (3) by the pressing force. A pressure developing device.