JPS5913248A - Image forming device - Google Patents

Abstract

PURPOSE:To obtain a device consisting of divided main bodies which are never pressed down even if a load increases by providing a pressure means to the 1st main body side when the 1st and the 2nd main bodies are closed to a release side. CONSTITUTION:The main body 1 is provided with an auxiliary pressure spring 16 which generates pressure by abutting on the 2nd main body 2 right before a hook 7 engages a catcher 9 in addition to spring rods 5 and 6 for elevating the 1st main body 1. While the main bodies 1 and 2 are closed, the main body 1 is applied with force generated by allowing the spring rods 5 and 6 and spring 6 to abut on a fixation device of the main body 2, so the main body 1 is never pressed down even if the load on an original platen 3 increases. Further, the bars 5 and 6 require only force enough for balancing with their weights where the main body 1 is fully open because of the spring 16, so no excessive torsional moment is applied to the main bodies 1 and 2; and the main body 1 never hops up even when the hook 7 is disengaged.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus such as a copying machine or a recording machine. In particular, the present invention relates to an image forming apparatus having a structure in which the main body can be divided into a first main body and a second main body.

Hereinafter, a copying machine whose main body can be divided into an upper unit and a lower unit will be described as an example.

Conventionally, as shown in Fig. 1, in a copying machine whose main body is divided into an upper unit and a lower unit, and the upper unit rotates around one end and has an opening, in the normally closed state, torsion bars, coil springs, etc. This pressurizes the upper unit in the opening direction to make it easier for the user to open the upper unit.

In the figure, 1 is the upper unit, 2 is the lower unit, 6 is the document table,
4 hinges, 5-6 are torsion bars. Also 7
is a hook, 8 is a hook shaft, and 9 is a catcher. Note that 10 is the vertical play between the hook catchers. In the illustrated copying machine, the upper and lower units 1 and 2 are usually connected by a hook 7, but the catcher 9 of the hook 7 is provided with a play to make it easier to hook the hook 7 thereon.

For this reason, 1. If a large downward load is applied to the document table 6, the upper unit 1 may be pushed down by the amount of play, which may adversely affect the conveyance of one sheet. To avoid this, if the torsion bars 5 and 6 are strengthened, the upper and lower units 1.
- Excessive twisting torque may be applied to the upper unit 2, or when the upper unit 1 is opened, the upper unit 1 may jump up, creating a danger to the user or applying a shock to the machine.

Therefore, the present invention provides an image forming apparatus that solves the problems of the conventional apparatus.

That is, the present invention that achieves the above object has a structure in which the main body can be divided into a first main body and a second main body, and when both main bodies are closed on the open side of the first main body and the second main body, The image forming apparatus is characterized in that an auxiliary pressurizing means for applying pressure is provided on the first main body side.

An embodiment of the present invention will be described below with reference to FIGS. 2, 3, and 4. Note that FIG. 4 mainly shows the upper and lower units 2 and the fixing device 11, and one image forming means is omitted.

In addition, the outer cover is omitted in each figure.

In the figure, 1 is an upper unit, 2 is a lower unit, 3 is a document table, and 4 is a hinge, which rotatably connects the upper and lower units 1 and 2. In addition, 5 and 6 are talk "17 bars, which apply the same force upward centering on the upper unit) IK upper hinge. Furthermore, 7 is a hook, 8 is a hook axis, and 9 is a catcher, which drives hook 7. By engaging with the catcher 9, the upper and lower units 1 and 2 maintain the closed state.
is the play between the hook catchers. Further, 11 is a fixing device, 12 is a fixing roller, 16 is a pressure roller, 14 is a top lid of the fixing device, and 15 is a hinge of the top lid. Further, 16 is an auxiliary pressure spring, which is located at both ends of the lower fixing plate 1a of the upper unit 1.
It is provided on the open side of the upper and lower units 2.

In FIG. 6, 17 is a photosensitive drum, 18 is a developing device, 19 is a short focus imaging element array as an optical system, and 2
0 is a charger, and 21 is a cleaning means, which are respectively arranged in the upper unit 1. , 22 is a cassette, 23 is a feeding roller, 24 is a guide, 25 is a transfer discharger, 26 is a guide, and 27 is a tray, which are arranged in the lower unit 2, respectively.

In the copying machine of the embodiment shown here, in addition to the torsion bars 5 and 6 for lifting the upper unit 1, an auxiliary pressurizer that generates pressure by contacting the lower unit 2 immediately before the hook 7 hooks on the catcher 9 is used. A spring 16 is provided on the upper unit 1.

Therefore, when the upper and lower units 1 and 2 are in the closed state, the upper unit IK is connected to the torsion bars 5 and 6 and the auxiliary pressure nozzle
Since the force generated by the document plate 6 coming into contact with the fixing device 11 of the lower unit 2, which will be described later, is applied, the upper unit 1 will not be pushed down even if the load on the document table 6 increases. Also, auxiliary pressure) (due to the presence of Ne 16, torsion bars 5 and 6
The force is enough to balance the upper unit 1 with its own weight when it is in the fully open position. Therefore, in the closed state, there is no excessive twisting moment applied to the upper and lower units 2, and the hook 7 can be removed. Even if the situation is good, Hi-unit 1 will not jump up.

On the other hand, in the fuser 11 of the copying machine according to the embodiment of the present invention, when a paper jam occurs, the upper unit 1 of the main body is opened upward, and then the upper cover 14 of the fuser 11 is opened around the shaft 15. The structure is such that the pressure between the fixing roller 12 and the pressure roller 16 is released via a link mechanism (not shown), and the paper can be easily taken out. Further, in this embodiment, since the auxiliary pressure spring 16 is brought into contact with the upper lid 14 in the closed state, an urging force is generated in the direction of the arrow. For this reason, it can be used as a fuser. Further, the operator can open the top lid 14 without performing any operation such as unlocking when handling a paper jam, and there is no need to check whether the top lid 14 is locked when closing it.

In addition, FIG. 3 shows a state in which the upper unit 1 is open, and in this state, the auxiliary pressure spring 16, which is a leaf spring with a short stroke, is free, and the upper unit) [is the torsion bar 5 and 6. Only force is added. Furthermore, in the above embodiments, the auxiliary pressure spring 16 may be a coil spring, and the object to which the auxiliary pressure spring 16 presses does not have to be the upper cover 14 of the fixing device 11, for example, by pushing the pressure roller 13 through a lever or the like. It may also be used as a pressure spring.

As explained above, in the copying machine equipped with the auxiliary pressure spring 16 of this embodiment, in the closed state, the upper unit 1 will not be pushed down even if the load on the machine 6 increases. Moreover, no excessive twisting torque is applied to the upper and lower units 1 and 2. Also, when the upper unit 1 tries to open, the force of the auxiliary pressure spring 16 is not applied immediately.
Upper unit 1 does not jump up. Furthermore, since the auxiliary pressure spring 16 also serves as the pressure spring for the upper lid 14 of the fixing device 11, the structure of the fixing device 11 is simplified, and the user has the advantage that the negative phase is small. .

As described above in detail, the present invention provides an image forming apparatus j6 in which the divided main body does not push down even when the load increases.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the configuration of a conventional copying machine, Fig. 2 is a side view showing an embodiment of the copying machine provided with an auxiliary pressure spring according to the present invention, and Fig. 6 is a side view showing the configuration of a conventional copying machine. FIG. 4 is a side view showing the copying machine in an open state, and FIG. 4 is a perspective view thereof. In the figure, 1 is T unit, 2 is F unit, 5 k
'K JQ harmony, 4 G-J, hinge, 5 and 6 are torsion springs, 7 is hook, 8 is hook shaft, 9 is catcher, 10 is catcher play, 11 is fixing device, 12 is fixing roller, 13 is application roller; 14 is a fixing device-upper lid;
15 is a hinge of the upper lid, and 16 is an auxiliary pressure spring. Applicant Canon Co., Ltd.

Claims (2)

[Claims] (1) The main body has a structure that can be divided into a first main body and a second main body, and an auxiliary pressure means is provided on the open side of the first main body and the second main body to pressurize both main bodies when both main bodies are closed. An image forming apparatus characterized in that it is provided on one main body side. (2) The image forming apparatus according to claim (1), wherein the auxiliary pressurizing means pressurizes the fixing device on the second main body side.