JPH0552933B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sensor mounting structure used in a document size detection system of a copying machine, and particularly to a type in which the sensor is installed inside a document cover for opening and closing a platen. This invention relates to improvements in sensor mounting structures.

[Prior Art] Generally, a copying machine selects a copy sheet corresponding to a document of various sizes placed on a platen, and copies the contents of the document onto the selected copy sheet. In order to ensure the paper selection operation, a method has already been proposed in which the document size is automatically detected.

Conventional document size detection systems include those shown in FIGS. 6 and 7, for example. This is the document cover 2 that opens and closes the platen 1.
There are a plurality of sensors S for detecting the document size inside, for example, four (indicated by S1 to S4 in FIG. 6).
each sensor S when the document cover 2 is closed.
Based on the output, it is determined whether the portion corresponding to each sensor S is four sides of the original or one side of the platen, and the size of the original is detected. To elaborate further,
As shown in FIG. 7, each sensor S includes a light-emitting element 5 that emits light toward the platen 1 when the document cover 2 is closed, and a light-receiving element 6 that detects the amount of light reflected from the irradiation surface. If the irradiated surface corresponding to each sensor S is the fourth surface of the document, most of the irradiated light from the light emitting element 5 will be reflected, so that the amount of light received by the light receiving element 6 will increase; When the irradiation surface corresponding to each sensor S is the platen 1 surface, most of the irradiation light from the light emitting element 5 passes through the platen 1, so that the amount of light received by the light receiving element 6 is almost eliminated. Therefore, based on the output of each sensor S, it is reliably determined whether the irradiation surface corresponding to each sensor S is four originals or one platen. For example, each original size P
1, P2, P3, if the sensors S1, S2 are arranged opposite to the original size P2, P3, and the sensors S3, S4 are arranged opposite to the original size P3, the original detection signal (light receiving element 6
(sensor output when the amount of received light is large) cannot be obtained, the document size is P1, sensor S1,
If a document detection signal is obtained only from S2, the document size is detected as P2, and if document detection signals are obtained from each of the sensors S1 to S4, the document size P3 is detected. Note that 7 in FIG. 7 is a lead wire of the sensor S.

By the way, the document cover 2 used in such a document size detection system is, for example,
As shown in the figure, a cover base 8 made of a hard insulating plate or the like, and a transparent film 9 such as a white polyester film that forms the background of the document 4 area.
The platen 1 is interposed between the members 8 and 9.
It consists of a cushion material 10 that presses down the upper document 4.

As shown in FIG. 8, for example, as shown in FIG. 8, a conventional sensor mounting structure for such a document cover 2 includes an accommodation hole 11 formed in a portion of the cushion material 10 corresponding to the sensor mounting location, and a housing hole 11 corresponding to the sensor mounting location. A positioning embossment 12 is formed on the film 9 to maintain a constant gap δ between the surface of the sensor S and the irradiation surface, and the housing hole 11 is
The sensor S is accommodated in the interior, and the surface of the sensor S is attached to the top surface of the positioning embossing 12 with an adhesive 1.
3, or as shown in FIG. 9, a substrate 14 is fixed to the lower surface of the cover base 8 corresponding to the sensor mounting site, and the sensor S is fixed to the housing hole 11 made in the cushion material 10. The lead wire 7 of the sensor S is fixed to the substrate 14, and the surface of the sensor S is placed in contact with the top surface of the positioning embossing 12 formed on the film 9. As shown, the sensor S is fixed to the unit case 15 in advance, and the unit case 15 is accommodated and fixed in the accommodation hole 11 made in the cushion material 10, and the top of the positioning embossing 12 formed on the film 9 is fixed. There is one in which the surface of the sensor S is placed in contact with the surface. In each conventional example, the lead wire 7 is connected to a harness not shown.

[Problems to be Solved by the Invention] However, in such a conventional sensor mounting structure, when the cushion material 10 is If the film 9 is locally significantly elastically deformed, in both cases, there is a risk that the sensor S will be peeled off from the fixed part, so that not only will the sensor S be insufficiently held, but the sensor S
If it comes off from its fixed part, the surface of the sensor S will be tilted with respect to the irradiation surface, and the gap δ between the surface of the sensor S and the irradiation surface will change, making the detection operation of the document 4 by the sensor S uncertain. It becomes a thing. In order to resolve this situation,
It is conceivable to set the elastic modulus of the cushion material 10 to a large value to reduce the amount of elastic deformation of the cushion material 10, but in this case, the thick document 4 cannot be held evenly, and the original document 4 of the document cover 2 cannot be held down evenly. The problem arises that the function is impaired.

In addition, in the conventional example shown in FIGS. 8 and 9, when assembling the sensor S, the sensor S is directly inserted into the accommodation hole 11 having a relatively small diameter, and the sensor S is attached to the top surface of the positioning embossing 12. The surface of the sensor S has to be positioned, and in the conventional example shown in FIG. The unit case 15 must be fixed and the surface of the sensor S must be positioned on the top surface of the positioning embossing 12. For this reason, not only does the assembling work of the sensor S become relatively troublesome, but also in each of the above mounting structures, the sensor S is positioned and fixed within the accommodation hole 11 during assembly, so that when the sensor S fails, A problem arises in that the task of replacing the sensor S becomes extremely troublesome.

[Means and effects for solving the problem] This invention has been made by focusing on the above problem, and its object is to provide a document cover without impairing the original document holding function. , in a document detection system for a copying machine that securely holds a sensor inside the document cover, allows the sensor to perform document detection operations reliably at all times, and also facilitates sensor assembly and replacement work. The object of the present invention is to provide a sensor mounting structure. In order to accomplish this task, this invention
Assuming that the document cover is of a type in which a sensor for detecting the document is provided inside the document cover, which is made by interposing a cushion material between the cover base and the transparent film, an accommodation hole for accommodating the sensor is provided in the cushion material. An elastic body is provided on the lower surface of the cover base corresponding to each of the accommodation holes, and a holder for holding each sensor is fitted into each of the accommodation holes so as to be movable up and down, and the elastic body and the transparent film are connected to each other. The sensor is held between the two via a holder. Therefore, the sensor inside the document cover is restrained in position in its surface direction and in the vertical direction due to the presence of the holder and the pressing action of the elastic body, so that the sensor's holding condition and mounting posture are always maintained in a good condition. Furthermore, due to the presence of the elastic body, a sufficient amount of elastic deformation of the cushion material at the sensor mounting portion is ensured. Furthermore, the sensor is housed in the accommodation hole on the cushion material side together with the holder, and is simply held between the cover base and the film on the bottom surface of the cushion material, so the sensor can be easily inserted into the document cover. This means that it can be easily replaced in the event of a failure.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the accompanying drawings.

In the embodiment shown in FIGS. 1 to 5, the document cover 2 includes a cover base 8 formed of a hard insulating plate or the like, and a white polyester film or the like forming the background of the document 4 area, as in the conventional case. It consists of a transparent film 9 and a cushion material 10 interposed between both members 8 and 9.

In this embodiment, the cover base 8 includes:
One end of the cover base 8 is attached to the fuselage via a hinge 20, and a mounting surface 21 for fixing the cushion material 10 is formed protruding from the back surface of the cover base 8 on both sides of the hinge 20 in the axial direction. The cushion material 10 is attached to the housing via double-sided tape 22 or the like. Also,
A plurality of sensor accommodating holes 11, for example four, are opened at appropriate locations in the cushion material 10, and positioning embossing 12 is formed on the film 9 corresponding to the sensor accommodating holes 11. A presser cushion 25 as an elastic body is attached to the lower surface of the cover base 8 corresponding to the cover base 8.

Further, each sensor S for detecting the document is connected to the holder 3 respectively.
It is held at 0. Each holder 30 consists of a box-shaped holder main body 31 with an open top, and a holder lid 35 that closes the top opening of the holder main body 31.
2 is provided, and a holding groove 33 for holding each sensor S is formed in the center of the recess 32, and
A draw-out opening 34 for drawing out the lead wires 7 from each sensor S is provided at the bottom of the holder main body 31. On the other hand, the holder lid 35 is provided with extraction holes 36 for guiding the lead wires 7 inside the holder body 31 to the outside, and the lead wires 7 from each extraction hole 36 are connected to a control device (not shown) via a harness 40. It is becoming more and more common. Then, the holder main body 31
Each sensor S is fixed in advance to the holding groove 33 of the sensor S through a fastener (not shown) such as a screw, and the lead wire 7 is drawn out from the draw-out opening 34 and the holder lid 35 is fixed in advance.
By previously inserting the lead wire 7 into the lead-out hole 36 of the sensor, closing the holder body 31 with the holder lid 35, and connecting the lead wire 7 drawn out outside the holder 30 to the harness 40, the sensor can be removed. S, the holder 30, and the harness 40 constitute one sensor assembly A. and again,
The holder main body 31 has a slightly smaller outer shape than the sensor housing hole 11, and fits into the housing hole 11 so as to be able to move up and down. The holder lid 35 is arranged to project slightly upwardly from the upper surface of the cushion material 10, and the lower surface of the holder lid 35 is spaced apart from the upper surface of the cushion material 10. Furthermore, in this embodiment, the holder 30
The lower surface of the bottom is arranged to protrude downward from the top surface of the positioning embossing 12, so that the top surface of the positioning embossing 12 protrudes into the recess 32 of the holder 30.

Further, on the back surface of the cover base 8, several ribs 50 are provided to protrude toward the cushion material 10 side, and the protruding end of each rib 50 is connected to the cushion material 10.
It is spaced apart from 0. Furthermore, a biasing spring 51 is provided on the hinge 20 that supports the cover base 8.
1 presses and urges the cover base 8 toward the platen 1 side when the document cover 2 is closed, and urges the cover base 8 toward the non-platen 1 side when the document cover 2 is opened, thereby controlling the opening/closing operation of the document cover 2. It's starting to stabilize. In FIGS. 1 to 4, reference numeral 52 is a grip provided on the cover base 8 to open and close the document cover 2, and 53 is a grip provided on the top surface of the cover base 8 to temporarily store the document during a copy operation. This is a pocket for storing documents.

Therefore, when assembling the sensor S to the document cover 2, as shown in FIG. Next, each sensor S of the sensor assembly A is accommodated together with the holder 30 in each accommodation hole 11 of the cushion material 10, and then the cover base 8 is attached while pulling out the harness 40 of the sensor assembly A to the outside. The cushion material 10 may be fixed to the surface 21 with a double-sided tape 22 or the like.

According to the sensor mounting structure assembled in this way, especially as shown in FIG. is restrained in its surface direction, and since the holder 30 is in elastic contact with the presser cushion 25 on the cover base 8 side, the holder 30 is pressed downward, and the sensor S is pressed against the film 9.
The sensor S is always pressed against the top surface of the positioning embossing 12, and the sensor S is also restrained in the vertical direction. Therefore, even if the cushion material 10 and the film 9 are partially elastically deformed due to the impact when opening and closing the document cover 2 or when pressing the thick document 4, the sensor inside the document cover 2 A situation in which the retained state of S is impaired does not occur. Therefore, the sensor S surface always remains in contact with the top surface of the positioning embossing 12, and as a result, the sensor S surface faces the above-mentioned irradiation surface in the correct posture. The gap δ between the image and the irradiation surface also becomes constant, and the detection operation of the original 4 by the sensor S becomes more accurate accordingly.

In addition, the cushion material 1 near the sensor S installation site
Even if the cushion material 10 undergoes a large elastic deformation, the elastic deformation of the cushion material 10 is effectively absorbed by the holding cushion 25, as shown by the imaginary line in FIG. The amount of elastic deformation of the document cover 2 does not become smaller than that of other parts, and the original document 4 holding function of the document cover 2 is maintained well.

Furthermore, in this embodiment, if the sensor S fails, the cushion material 10 is peeled off from the cover base 8, and then the sensor assembly A is removed and the sensor assembly A is removed.
The sensor S may be removed from the sensor S and the failed sensor S may be replaced with a new sensor S, or the sensor assembly A may be replaced entirely. At this time, since each member constituting the document cover 2 is used as is, the document cover 2
Each component is not wasted, and the sensor S can be easily replaced. Furthermore, even if the elastic action of the cushion material 10 is impaired or the film 9 becomes dirty, it is possible to replace only the cushion material 10 and the film 9 without replacing the entire document cover 2.

Furthermore, in this embodiment, a gap 60 is formed between the lower surface of the cover base 8 and the cushion material 10, but since the rib 50 is protruded from the back surface of the cover base 8, When the document cover 2 presses the document 4, the cushion material 10
comes into contact with the rib 50, and upward movement of the cushion material 10 is restricted. Therefore, the cushion material 10 does not become unnecessarily sticky.
Correspondingly, the function of holding the original 4 by the original cover 2 is maintained well. In addition, in this embodiment, the original 4
If a large downward load is applied to the top surface of the positioning embossing 12 during pressing, there is a risk that the positioning embossing 12 will be crushed and deformed.
, the lower surface of the holder 30 comes into contact with the general surface of the film 9 before the positioning embossing 12 collapses and deforms, and the collapse of the positioning embossing 12 is effectively suppressed.

In the above embodiment, the presser cushion 25 is provided on a part of the cover base 8 side, but the presser cushion 25 is not necessarily limited to this, and the presser cushion 25 may be provided on the entire lower surface of the cover base 8. It's okay. Furthermore, in the above embodiment,
Although the presser cushion 25 is used as the elastic body, any elastic member such as a spring may be selected as appropriate. Furthermore, the members such as the holder 30 that holds the sensor S and the cover base 8 are not limited to those shown in the above embodiments, and it goes without saying that the design can be changed as appropriate.

[Effects of the Invention] As described above, according to the sensor mounting structure in the document size detection system for a copying machine according to the present invention, the sensor is restrained and held inside the document cover using the holder and the elastic body. Therefore, even if the document cover undergoes large local elastic deformation, the sensor will not move unnecessarily.
In addition to being able to hold the sensor reliably at all times, the relative positional relationship between the sensor surface and the irradiation surface can be maintained constant, so that the sensor can ensure the document detection operation. Further, according to this invention,
Since the elastic deformation of the cushion material corresponding to the sensor mounting area is sufficiently ensured by the elastic body on the cover base side, there is no concern that the original document holding function of the document cover will be impaired. Further, according to the present invention, since the sensor is simply sandwiched together with the holder between the constituent members of the document cover, there is no need to position and fix the sensor to the sensor housing hole of the cushion material as in the conventional case. This eliminates the need for installation and replacement of the sensor.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a sensor mounting structure in a document size detection system for a copying machine according to the present invention, FIG. 2 is a view taken from the direction of the arrow in FIG. 1, and FIG. A cross-sectional view corresponding to the line - in Figure 1, Figure 4 is a cross-sectional view corresponding to the line - in Figure 3,
Fig. 5 is an explanatory cross-sectional view of the main part showing the mounting state of the sensor, Fig. 6 is an explanatory view showing the outline of the document size detection system of the copying machine, Fig. 7 is an explanatory view showing its principle, and Figs. FIG. 10 is a cross-sectional explanatory view showing different examples of mounting structures for a sensor for detecting document size in a conventional copying machine. Explanation of symbols, S, S1 to S4...Sensor, 1
...Platen, 2...Document cover, 4...Document,
5... Light emitting element, 6... Light receiving element, 8... Cover base, 9... Film, 10... Cushion material, 11... Sensor housing hole, 25... Presser cushion (elastic body), 30... Holder .

Claims (1)

[Claims] 1. A document cover for opening and closing the platen is composed of a cover base, a white transparent film, and a cushion material interposed between the two, and a plurality of sensor accommodation holes are provided at appropriate locations in the cushion material, and Each sensor housing hole is provided with a sensor that irradiates light toward the platen when the document cover is closed and detects the amount of reflected light from the irradiation surface, and a sensor corresponding to each sensor is arranged based on the output of each sensor. In a copying machine document size detection system that detects the document size by determining whether the irradiated surface is either the document surface or the platen surface, an elastic material is attached to the lower surface of the cover base corresponding to each accommodation hole of the cushion material. A holder for holding each sensor is fitted into each of the accommodation holes so as to be movable up and down, and the sensor is sandwiched between the elastic body and the transparent film via the holder. A sensor mounting structure in a document size detection system for a copying machine, which is characterized by: