JPS61197339A - Paper feed mechanism - Google Patents

Abstract

PURPOSE:To prevent paper from skewing when being fed by a paper feed mechanism for a printer or the like, by setting equal outside diameters and equal hardnesses for paper feed rollers, paper push rollers and their elastic materials, respectively. CONSTITUTION:A paper feed mechanism comprises a paper feed roller assembly 1 and a paper push roller assembly 2 fitted with springs 3 or the like which exert pushing forces. A turning force is applied from a driver 5 to the paper feed roller assembly 1 through a motive power transmitting portion 4. Equal outside diameters are set for paper feed rollers 8 and paper push rollers 9, respectively. Equal hardnesses are set for the elastic materials of the rollers 8 and 9, respectively. As a result, different sizes 6, 7 of paper can be fed without skewing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention J] The present invention relates to a paper feeding mechanism, and more particularly to a paper feeding mechanism that can prevent sheets from becoming skinny.

[Background of the invention]

Generally, a paper feed mechanism is used in, for example, a printer or an optical character reading device, and conveys paper by rotating a paper feed roller. However, a phenomenon in which the paper is often conveyed at an angle, that is, a so-called skinny phenomenon occurs. For example, this skinny can cause inconveniences in printers, such as characters not being printed in the specified position or printing itself, and in optical character reading devices, character strings are slanted, making character confirmation completely impossible. This may cause inconvenience such as becoming possible.

To prevent this, as a conventional technique, Japanese Patent Application Laid-Open No. 59-9
As described in Japanese Patent Application Laid-open No. 1076, Japanese Patent Application Laid-open No. 59-140085, and Japanese Patent Application Laid-open No. 59-143664, the paper feeding state is detected by an optical sensor or the like, and the paper feeding roller is activated based on this detection signal. A mechanism for correcting skinny by controlling the driving of a driving stepping motor is known. However, these mechanisms only correct the skinny that has occurred, but cannot prevent the skinny from occurring itself.

In addition, to prevent the occurrence of skinny, it is also possible to provide a mechanism or a paper guide in which a paper press roller is arranged in a square shape with respect to a paper feed roller as described in Japanese Patent Application Laid-open No. 59-164170. However, recent printers and optical character reading devices are required to print or read on paper of different sizes, and these known techniques cannot handle paper of different sizes.

[Purpose of the invention]

The purpose of this invention is to eliminate the above-mentioned conventional problems, and to eliminate the occurrence of skinny itself without using a detection mechanism or correction mechanism for skinny detection, and regardless of the paper. An object of the present invention is to provide a paper feeding mechanism that can prevent the above problems.

[Summary of the invention]

The feature of this invention is that in order to prevent skinny, which has been a problem in paper feeding in the past, the outer diameter and hardness of the elastic rollers, which have a large effect on the paper feeding characteristics, are measured in advance to ensure the same quality. By using a paper feed roller and a paper pressing roller that are composed of elastic rollers, the paper can be conveyed in parallel.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to the drawings.

@ Figure 1 is a sketch showing an example of a paper feeding mechanism, Figure 2 is a plan view illustrating changes in feed amount due to differences in roller outer diameter, and Figure 3 is a plan view illustrating changes in feed amount due to differences in roller hardness. FIG.

In general, a paper feed mechanism consists of a paper feed roller assembly 1 and a paper presser roller assembly 2. A rotational force from a drive source 5 is applied to the power transmission section 4 . -10,000 Paper sizes may be different, such as paper A6 and paper B7. In this paper feeding mechanism, as shown in FIG. 2, the outer diameter dimensions of the paper feeding roller 8 and paper pressing roller 9 are as follows.
If there is a difference in one roller assembly, the outer circumference of the roller will be different, and even with one revolution of the same shaft, the paper feed fiA will be skinny by the amount of difference in the outer circumference of the roller. Further, as shown in Fig. 233, if the hardness of the paper feed roller 8 and the paper press roller 9 are different, the frictional force of the contact surface with the paper will be different, which will also cause skinny.

In order to prevent the occurrence of these skinny defects, as shown in the exploded perspective view of the roller assembly (4), the shaft 10 and roller 11 are constructed so that they can be assembled with 12% screws (adhesive etc. are also possible). As shown in FIG.
As shown in Fig. 6, the hardness measuring device 13 is applied to the outer periphery of the roller 11, and a certain pressure is applied to the elastic body, and a deformation H is applied to the body.The amount of deformation is measured as the hardness of the elastic body. Alternatively, by the amount of pressure on the elastic body when a constant deformation iH is applied,! As shown in the table, the 70th rank is divided into ranks based on external dimensions and hardness, and by using parts of the same rank to form one roller assembly, parallel paper feeding is possible. It becomes possible.

FIG. 8 is an external view showing an embodiment of an automatic sorting device for paper feed rollers that automatically measures and sorts the characteristics (external dimensions and hardness) of the paper feed roller 8 and the paper presser roller 9. Further, FIG. 9 is an operation flowchart showing the operation of this device.

This device includes a roller supply section 14, a hardness measurement section 16 to an outer diameter measurement section 15, a control section 18 that stores and discriminates the measurement results, controls the transport robot 17 based on the discrimination results, and discharges the rollers after sorting. As shown in the flowchart No. 9, the roller supply section 14
Then, the roller 11 is taken out and transported to the outer diameter measuring section 15 (B). It is detected that the roller 11 is conveyed to the outer diameter measurement section 15, the outer diameter dimension is automatically measured, the result is electronically transmitted to the control section 113C, and the measured value is stored and discriminated in the control section 18. In response to the measurement completion signal from the tcn0 outer diameter measuring section 15, the transport robot 17 transfers the roller 11 from the outer diameter measuring section 15 to the hardness measuring section 16 (/-4
(Similarly, the transfer of the roller 11 is detected, the hardness is automatically measured, and the measured value is electronically transmitted to the control unit 1B for storage and discrimination). Next, the control unit 18 ranks the outer diameter measurement value and the hardness measurement value, and issues a discharge command to the transfer robot 17 based on the results. Based on the command, the transport robot 17 discharges the material to the discharge section 19 that has been divided into predetermined ranks. This series of operations is repeated for the amount of roller stock in the roller supply section 14.

In this way, according to the present device, parts of the same rank are automatically determined and classified, so if the paper feeding mechanism is constructed using the classified parts, a paper feeding mechanism that prevents skinny is completed.

〔Effect of the invention〕

With the configuration described above, the present invention can provide the following effects.

(By incorporating 11 rollers according to their characteristics (outer diameter size and hardness), skinny occurrence itself (σ) can be prevented, and additional mechanisms such as skew detection are unnecessary, making it possible to reduce product cost.

(It can be applied to any of the different media in the 21 sheets and media with different paper qualities, and is effective for paper feeding mechanisms that handle many types of paper.

(3) By mechanizing the measurement and determination of roller characteristics (outer diameter dimensions and hardness) from the conventional manual work, it is possible to significantly reduce the number of man-hours.

+41 By automatically measuring the roller characteristics (outer diameter and hardness) of all parts, it is possible to prevent the inclusion of defective parts and improve product quality.

[Brief explanation of drawings]

Fig. 1 is a sketch of the paper feeding mechanism, Fig. 2 is a plan view illustrating paper feeding states with different roller outer diameters, Fig. 6 is a plan view illustrating paper feeding states with different roller hardness, and Fig. 4
The figure is an exploded perspective view of the roller assembly, Figure 5 is a plan view of the outer diameter of the roller, Figure 6 is a plan view of roller hardness measurement, and Figure 7 is a plan view of the roller hardness measurement.
The figure is a matrices length table showing the classification of roller outer diameter and hardness, FIG. 8 is an external view of an automatic paper feed roller sorting device, and FIG. 9 is an operation flowchart of the device shown in FIG. DESCRIPTION OF SYMBOLS 1... Paper feed roller assembly, 2... Paper press roller assembly, 3... Spring, 4... Power transmission section, 5... Drive source, 6... Paper handler, 7...・Paper B
, 8...Paper feed roller, 9...Paper press roller, 10...Shaft, 11...Roller, 12
. . . Screw, 16 . . . Hardness measuring device, 14 . . . Roller supply section, 15 . . Part, 19
・・・Discharge part map Figure 8

Claims (1)

[Claims] In a paper feeding mechanism that includes a paper feeding roller and a paper pressing roller, each of which is a roller whose outer periphery is made of an elastic body, and a shaft, the outer diameter dimension and hardness of the elastic body of the roller are measured in advance, and the same characteristics are determined. A paper feeding mechanism that prevents skew that occurs during paper feeding by incorporating rollers that hold the rollers into one shaft.