阅读说明：本技术 片材装订装置及图像形成系统 (Sheet binding apparatus and image forming system ) 是由 水谷企久夫 于 2019-12-11 设计创作，主要内容包括：本发明提供片材装订装置及图像形成系统,该片材装订装置具有第一辊、第二辊和辊隙压力调整部。第一辊将带安装于片材摞的边缘部。第二辊在片材摞厚度方向上与所述第一辊对置。辊隙压力调整部能够基于所述片材摞的边缘部前端的位置,对所述第一辊和所述第二辊形成的辊隙的按压力进行调整。在所述片材摞插入所述第一辊和所述第二辊之间之前,所述第一辊和所述第二辊之间的间隔为所述片材摞的厚度以下。(The invention provides a sheet binding apparatus and an image forming system. The first roller attaches the belt to an edge portion of the sheet bundle. The second roller is opposed to the first roller in the thickness direction of the sheet bundle. The nip pressure adjustment unit can adjust a pressing force of a nip formed by the first roller and the second roller based on a position of a leading end of an edge portion of the sheet bundle. The interval between the first roller and the second roller is equal to or less than the thickness of the sheet bundle before the sheet bundle is inserted between the first roller and the second roller.)

1. A sheet binding apparatus is characterized by comprising:

a first roller that attaches a belt to an edge portion of a sheet bundle;

a second roller opposed to the first roller in a thickness direction of the sheet bundle; and

a nip pressure adjustment unit capable of adjusting a pressing force of a nip formed by the first roller and the second roller based on a position of a leading end of an edge portion of the sheet bundle,

the interval between the first roller and the second roller is equal to or less than the thickness of the sheet bundle before the sheet bundle is inserted between the first roller and the second roller.

2. The sheet binding apparatus according to claim 1,

at least one of the first roller and the second roller has a shape of: a distance from the rotation shaft to the nip before the insertion of the sheet bundle is less than a threshold value and the distance after the insertion of the sheet bundle is the threshold value or more.

3. The sheet binding apparatus according to claim 2,

at least one of the first roller and the second roller includes: a minimum radius part having a minimum radius and a maximum radius part having a maximum radius,

the minimum radius portion forms the nip before the sheet bundle is inserted between the first roller and the second roller.

4. The sheet binding apparatus according to claim 2,

at least one of the first roller and the second roller has an elliptical shape or a cam shape.

5. The sheet binding apparatus according to claim 4,

the first roller has a perfect circular shape and is opposed to a stepped end surface of the sheet bundle,

the second roller has an elliptical shape and faces the opposite side of the stepped end surface of the sheet bundle.

6. The sheet binding apparatus according to any one of claims 1 to 5,

the sheet binding apparatus further includes:

a first urging member that urges the first roller toward the second roller;

a second biasing member that biases the second roller toward the first roller; and

and a guide member that guides the sheet bundle so that a front end of an edge portion of the sheet bundle faces an inner side of a central width between the first roller and the second roller.

7. The sheet binding apparatus according to any one of claims 1 to 5,

the sheet binding apparatus further includes:

a biasing member that biases the first roller toward the second roller;

a support member rotatably supporting the second roller; and

a guide that guides the sheet bundle so that a leading end of an edge portion of the sheet bundle faces a nip forming end of the second roller.

8. The sheet binding apparatus according to any one of claims 1 to 5,

the nip pressure adjustment unit includes: a sensor that detects a leading end of an edge portion of the sheet bundle, and a control portion that controls the pressing force based on a detection result of the sensor.

9. The sheet binding apparatus according to claim 8,

the control portion makes the pressing pressure larger than a pressing threshold after a set time elapses after the sensor detects the edge portion leading end of the sheet bundle.

10. An image forming system for forming an image on a sheet,

the sheet binding apparatus according to any one of claims 1 to 9 is provided.

Technical Field

The invention relates to a sheet binding apparatus and an image forming system.

Background

Conventionally, there is known a sheet binding apparatus that binds an edge portion of a sheet bundle with an adhesive tape. The sheet binding device includes a bundle making section and a tape mounting section. The bundle making section superimposes a plurality of sheets to produce a sheet bundle. The bundle making section forms a side portion of the sheet bundle in a step shape in order to secure a surface area when the belt is attached. The tape mounting portion mounts an adhesive tape-bound sheet bundle on an edge portion of the sheet bundle. The tape mounting portion includes a tape holding portion for holding the adhesive tape. The belt mounting portion includes a first roller and a second roller that face each other in a sheet bundle thickness direction. The adhesive tape held by the tape holding portion is peeled from the tape holding portion by inserting a sheet bundle shifted in a stepwise manner into the adhesive tape. Then, the sheet bundle is fed between the first roller and the second roller together with the adhesive tape, and the adhesive tape is adhered to the edge portion of the sheet bundle.

However, depending on the magnitude of the pressing force applied to the sheet bundle between the first roller and the second roller (between the rollers), the following problems may occur. For example, if the pressing force of the sheet bundle between the rollers is too small, the adhesive tape cannot be sufficiently stuck to the edge portion of the sheet bundle. On the other hand, for example, if the pressing force of the sheet bundle between the rollers is excessively large, the sheet bundle cannot enter between the first roller and the second roller.

Disclosure of Invention

A sheet binding apparatus according to an aspect is characterized by including: a first roller that attaches a belt to an edge portion of a sheet bundle; a second roller opposed to the first roller in a thickness direction of the sheet bundle; and a nip pressure adjusting portion capable of adjusting a pressing force of a nip formed by the first roller and the second roller based on a position of a leading end of an edge portion of the sheet bundle, wherein an interval between the first roller and the second roller is equal to or less than a thickness of the sheet bundle before the sheet bundle is inserted between the first roller and the second roller.

Drawings

Fig. 1 is a front view showing an image forming system of a first embodiment.

Fig. 2 is a front view showing an internal structure of the sheet binding apparatus of the first embodiment.

Fig. 3 is a side view illustrating an operation of changing the amount of offset between sheets. Fig. 3 (a) is a diagram illustrating a case where the amount of shift between sheets is relatively small. Fig. 3 (b) is a diagram illustrating a case where the amount of shift between sheets is relatively large.

Fig. 4 is a front view illustrating an operation of the sheet binding apparatus of the first embodiment.

Fig. 5 is a front view showing the action of the sheet binding apparatus next to fig. 4.

Fig. 6 is a front view showing the action of the sheet binding apparatus next to fig. 5.

Fig. 7 is a front view showing the action of the sheet binding apparatus next to fig. 6.

Fig. 8 is a front view showing the operation of the sheet binding apparatus next to fig. 7.

Fig. 9 is a front view showing the operation of the sheet binding apparatus next to fig. 8.

Fig. 10 is a front view showing the operation of the sheet binding apparatus next to fig. 9.

Fig. 11 is a front view illustrating an operation of the sheet binding apparatus of the comparative example.

Fig. 12 is a front view showing an internal configuration of a sheet binding apparatus according to a first modification of the first embodiment.

Fig. 13 is a front view showing an internal configuration of a sheet binding apparatus of a second modification of the first embodiment.

Fig. 14 is a front view showing an internal structure of the sheet binding apparatus of the second embodiment.

Fig. 15 is a front view showing an internal structure of the sheet binding apparatus of the third embodiment.

Fig. 16 is a diagram illustrating a state in which the first roller of the third embodiment faces the stepped end surface of the sheet bundle.

Fig. 17 is a diagram illustrating a state in which the first roller of the third embodiment passes a stepped end surface of the sheet bundle.

Fig. 18 is a front view showing an internal configuration of a sheet binding apparatus according to a first modification of the third embodiment.

Detailed Description