JP2684681B2 - Image reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an image reading apparatus that includes an image sensor detachably provided in a carriage of a printer or the like, and controls power supply to the image sensor. .

[Prior Art] Usually, the image sensor as described above is driven by a plurality of potentials including a ground level. For this reason, the image sensor has a plurality of connection terminals for each of the potentials, and when mounted on the carriage, these connection terminals come into contact with the connection terminals on the power supply side provided on the carriage. .

However, the image sensor, when attached to and detached from the carriage, may be
Electrical damage, in the worst case,
There was a problem of damage.

Conventionally, as an image reading apparatus that solves these problems, as shown in FIG. 6, a male connection terminal A3 at the ground level provided on the image sensor A1 is projected more than male connection terminals A5 at other potentials. In addition, there has been proposed a configuration in which a predetermined voltage is always applied to each female connection terminal A8, A9 on the carriage A7 side. That is, by making the male connection terminal A3 of the ground level project more than the other male connection terminal A5, when the image sensor A1 is mounted, the male connection terminal A3 of the ground level is connected to the other male connection terminal. Be sure to contact the ground level female type connection terminal A9 on the carriage A7 side earlier than the terminal A5, and conversely, when detaching, the ground level male type connection terminal A3 will separate at the end, and the image sensor A1 Prevents damage.

[Problems to be Solved by the Invention] However, in the conventional image reading apparatus, only the male connection terminal A3 at the ground level among the plurality of male connection terminals A3, A5 provided in the image sensor A1 is It is necessary to project the male connection terminal A5 from the male connection terminal A5, which causes a problem that the configuration becomes complicated. Further, since a predetermined voltage is constantly applied to the female connection terminals A8 and A9 on the carriage A7 side, there is a problem that power consumption is consumed even when the image sensor A1 is not operated, and the image sensor A1 causes the carriage A7 to operate. There is also a problem that when not attached to the, the female connection terminals A8 and A9 are in an open state, and there is a risk of short-circuiting the power supply due to an external factor.

The present invention has been made in view of the above problems, and while eliminating the electrical damage at the time of attaching and detaching the image sensor,
An object of the present invention is to provide an image reading apparatus having a simple configuration, capable of reducing power consumption and avoiding a risk of short-circuiting of a power source applied to a connection terminal on the carriage side.

Configuration of the Invention [Means for Solving the Problems] In order to achieve the above object, the present invention has the following structures as means for solving the above problems. That is, as illustrated in FIG. 1, the image reading apparatus of the present invention includes a platen M1 that supports the sheet P and a carriage M2 that moves in a direction perpendicular to the sheet feeding direction of the platen M1.
An image reading means M3 which is detachably provided on the carriage M2 and reads an image recorded on the sheet P supported by the platen M1; and a power supply for supplying power to the image reading means M3 for its operation. Image reading control means for receiving the image reading start command and the image reading stop command from the outside and supplying a control signal to the image reading means M3.
In the image reading apparatus provided with M5, an attachment / detachment state detection means M6 for detecting an attachment / detachment state of the image reading means M3 to / from the carriage M2, and the attachment / detachment state detection means M6 sets the image reading means M3 to the attachment state. When it is detected that the image reading control means M5 receives an image reading start command, the image reading control means M5 starts the power supply to the image reading means M3 by the power supply means M4. And a power supply control means M7 for stopping the power supply to the image reading means M3 by the power supply means M4 when the image reading stop command is received.

[Operation] In the image reading apparatus of the present invention configured as described above, the image reading means M3 is moved to the carriage by the attachment / detachment state detecting means M6.
Image read control means that is detected to be mounted on M2
When M5 receives the image reading start command, the power supply means M7 starts power supply from the power supply means M4 to the image reading means M3, and the image reading control means M5 controls the image reading means M3. Image output means
The image recorded on the sheet P supported by the platen M1 is read by the M3 based on the control signal. Further, when the image reading control unit M5 receives the image reading stop command, the image reading control unit M5 stops reading the image recorded on the sheet P, and the power supply unit M7 functions to stop the power supply.

[Embodiment] Next, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a perspective view of a portable microcomputer provided with an image reading device according to an embodiment of the present invention, and FIG. 3 is an enlarged perspective view of the vicinity of the carriage and image sensor of the portable microcomputer. The figure is a block diagram showing an electrical configuration of the portable microcomputer. Note that, unlike FIG. 2, FIG. 3 is a view of a state in which the mounting surface of the image sensor faces upward.

As shown in FIG. 2, the portable microcomputer 1
Is a keyboard 3 in which a large number of keys are arranged, and a liquid crystal display 5 which is rotatably supported by the main body to display characters.
A printer 7 that prints characters on a sheet (not shown); an image sensor 11 that is detachably attached to a carriage 9 of the printer 7 and that reads an image on the sheet; and an external storage device. A floppy disk device 13 is integrally provided. In addition, on the side surface of the main body,
A power switch 15 is provided.

The image sensor 11 is a contact type that incorporates an LED light source, a SELFOC lens, and a charge storage type optical sensor unit, and reads an image printed on a sheet as image data in dot units. The user mounts the image sensor 11 on the carriage 9 when he / she wants to capture the image written on the read document into the portable microcomputer 1. As shown
The plurality of spring-shaped electrodes 17 provided on the side of the mounting surface 11a of the image sensor 11 to be mounted on the carriage 9 come into contact with the plurality of plate-shaped electrodes 19 provided on the surface of the carriage 9, respectively. It is electrically connected to the 7 side.

There are eight spring-shaped electrodes 17 and eight plate-shaped electrodes 19, and the first spring-shaped electrode 17a (plate-shaped electrode 19a) is for supplying a ground-level potential for driving the image sensor. Third spring-shaped electrode 17b (plate-shaped electrode 19b)
Is for supplying a potential other than the ground level for driving the image sensor. The fourth to seventh spring-shaped electrodes 17c (plate-shaped electrodes 19c) are for supplying read data from the image sensor, control signals to the image sensor, and the like.

The remaining eighth spring-shaped electrode 17d is connected to the ground-level first spring-shaped electrode 17a, and a small level electrical signal of a predetermined level is applied to the eighth plate-shaped electrode 19d. Has been. When the image sensor 11 is mounted on the carriage 9, the eighth plate-shaped electrode 19d becomes the eighth spring-shaped electrode 1
The ground level is reached via 7d, and the attachment / detachment state of the image sensor 11 can be detected from this result.

Further, as shown in FIG. 4, inside the portable microcomputer 1, a main controller 20 for performing various data processing and controlling the keyboard 3, the liquid crystal display 5, the floppy disk device 13 and the like, and Printer control device 30 for controlling the printer 7 and the image sensor 11
A power source 41 for supplying a voltage to both of the control devices 20 and 30 via a power switch 15; and a power source 41 connected to the power source 41 via a power switch 15 and a switching circuit 43. A power supply circuit 45 for supplying a ground-level potential to the plate electrode 19a and + 5V and -5V potentials to the second and third plate electrodes 19b is incorporated.

The main controller 20 is a well-known arithmetic logic operation circuit that functions as the brain of the portable microcomputer 1, and outputs an image reading start command and an image reading stop command to the printer controller 30. Since the main controller 20 is a part that is not directly related to the gist of the present invention, detailed description of its configuration is omitted.

The printer control device 30 includes a well-known CPU 30a, ROM 30b, RAM 3
The printer interface 30d configured as an arithmetic logic operation circuit centering on 0c and the like outputs a control signal and print data to the printer 7, outputs a control signal to the image reading device 11, and outputs the image data read from the image reading device 11. An image reading interface 30e for input, a switching interface 30f for outputting an ON / OFF control signal to the switching circuit 43, an image for outputting an electric signal of a predetermined level to the eighth plate electrode 19d of the image sensor 11 and reading the level of the output signal An interface 30g for detecting sensor attachment / detachment, a serial interface 30h for exchanging data with the main controller 20, and the like are provided, and these are connected to each other via a bus line 30i.

As shown in FIG. 2, the keyboard 3 includes a normal character key 33 corresponding to a character to be input, as well as various characters for editing and printing characters, reading an image written on a read original, and the like. Function keys 35 and the like are provided. Therefore, the main controller 20 takes in the key image from the keyboard 3 and, in response to the instruction from the keyboard 3,
Performs various data processing.

On the other hand, the printer 7 is a serial type having a 24-dot thermal head 37 with a resolution of 1/180 inch, and a thermal transfer type ribbon cartridge is loaded on the carriage 9 in place of the image sensor 11, so that Characters or images can be printed on. Note that printing can also be performed by using thermal paper instead of mounting anything on the carriage 9. The printer 7 is provided with, as its drive unit, a head-conveying motor for feeding the carriage 9 in the paper width direction, a paper-feeding motor for feeding the paper by the platen 39, and the like.
Connected to 30.

Next, the processing executed by the printer control device 30 will be described.

The CPU 30a of the printer control device 30 performs the following data processing while temporarily reading and writing the necessary data in the RAM 30c according to the procedure (program) stored in the ROM 30b in advance. That is, the process of receiving the image data sent from the main control device 20 and printing the image data, controlling the drive unit of the printer 7, and using the image sensor 11 to print the image written on the read original. A process of reading the image data as a unit and transmitting the image data to the main controller 20 via the serial interface 30f, and controlling the switching circuit 43 to be turned on and off, thereby starting and stopping the power supply to the image sensor 11. Process for controlling the.

Next, the process of suppressing the start timing and the stop timing of the power supply will be described in detail with reference to the flowchart of FIG.

When the process is started, it is first determined whether or not the image sensor 11 is mounted on the carriage 9 (step 100: hereinafter, "step" is abbreviated as "S"). This determination is made based on whether or not the potential of the plate-shaped electrode 19d for detecting the image sensor attachment / detachment of the carriage 9 is at the ground level, and the potential is read via the image sensor attachment / detachment interface 30g.
Determine if you are at ground level. If it is determined in S100 that the potential of the plate electrode 19d is a predetermined potential other than the ground level, that is, the image sensor 9 is not mounted, the process repeats S100. On the other hand, the plate electrode 19d
When it is determined that the potential of is at the ground level, that is, the image sensor 9 is attached, the process proceeds to S110.

In S110, the image reading start command is issued by the main controller 20.
From the serial interface 30h, and if it is determined that the image reading start command has not been received, the process returns to S100. on the other hand,
If it is determined that the image reading start command is received, the process proceeds to S120.

In S120, in order to start the power supply of the image sensor 11, a control signal for turning on the switching circuit 43,
It outputs to the switching circuit 43 from the switching interface 30f. Next, the image reading interface 30
Output various control signals from e to the image sensor 11,
In order to operate the image sensor 11, output of various control signals is started (S130). After that, the command to stop reading the image is issued from the main controller 20 via the serial interface.
It is determined whether or not the image is received via 30h (S140), and the process of S140 is repeated until the command to stop reading the image is received. If it is determined in S140 that the image reading stop command has been received, then various control signals output from the image reading interface 30e to the image sensor 11 in S130 are output to stop the operation of the image sensor 11. Stop (S150). Subsequently, in order to stop the power supply to the image sensor 11, a control signal for turning off the switching circuit 43 is output from the switching interface 30f to the switching circuit 43. After executing S160, the process is S1.
The process returns to 00 and the processing of this routine is repeated.

As described above in detail, in the portable microcomputer 1 of this embodiment, the power supplied to the power source plate electrodes 19a and 19b provided on the carriage 9 is controlled as follows. That is, when the image sensor 11 is mounted on the carriage 9 and the printer control device 30 receives the image reading start command from the main control device 20, the power supply is started and the main control device 20 sends the power. When the printer control device 30 receives the image reading stop command, the power supply is stopped. Therefore, when the image sensor 11 is attached or detached, power supply to the plate electrodes 19a and 19b for power supply provided on the carriage 9 is always stopped, and therefore the image sensor 11 is electrically damaged. Never receive. Moreover, in spite of such an effect, it is not necessary to take a mechanical configuration in which only the male connection terminal at the ground level is projected from the other male connection terminals as in the conventional example, and the configuration is complicated. There is nothing to do. Further, since the power supply is stopped when the image sensor 11 is not operating, it is possible to reduce power consumption, and further, since the power supply is stopped when the image sensor 11 is not mounted, the power supply is stopped. It is possible to prevent the power supply from being short-circuited due to an external factor during mounting.

Although the embodiments of the present invention have been described above, the present invention is not limited to such embodiments. For example, instead of the plate-like electrode 19d as the attachment / detachment state detection means M6, a protruding pin when the image sensor 11 is attached. Needless to say, the present invention can be implemented in various modes without departing from the scope of the present invention, such as a configuration in which a mechanical switch having a concave shape is attached to the carriage 9.

EFFECTS OF THE INVENTION As described in detail above, the image reading apparatus of the present invention has a simple structure while reducing the electrical damage when the image sensor is attached and detached, reduces power consumption, and supplies power to the connection terminal on the carriage side. It is possible to avoid the danger system of short circuit.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating the basic configuration of the present invention, FIG. 2 is a perspective view of a portable microcomputer provided with an image reading device according to an embodiment of the present invention, and FIG. 3 is its portable microcomputer. FIG. 4 is an enlarged perspective view of the vicinity of the carriage and the image sensor, FIG. 4 is a block diagram showing the electrical configuration of the portable microcomputer, and FIG. 5 is a flowchart showing one process executed by the printer control device. The figure is an enlarged perspective view of the vicinity of the carriage and the image sensor of the conventional example. P: Paper M1: Platen, M2: Carriage M3: Image reading means, M4: Power supply means M5: Image reading control means M6: Attachment / detachment state detection means M7: Power supply control means 1 ... Portable microcomputer 7 ... Printer, 9 ... Carriage 11 ... Image sensor 17a-17d ... Spring-shaped electrodes 19a-19d ... Plate-shaped electrode 20 ... Main controller, 30 ... Printer controller 41 ... Power supply 43 ... Switching circuit 45 ... Power supply circuit

Claims (1)

(57) [Claims] 1. A platen which supports a sheet, a carriage which moves in a direction perpendicular to the sheet feeding direction of the platen, and an image which is detachably provided on the carriage and which is recorded on the sheet supported by the platen. Image reading means for reading the image reading means, a power supply means for supplying power to the image reading means for its operation, an image reading start instruction and an image reading stop instruction from the outside, and the image reading means receives the image reading means. An image reading control device for outputting a control signal, comprising: an attachment / detachment state detection unit for detecting an attachment / detachment state of the image reading unit with respect to the carriage; The power supply to the image reading means by the power supply means is detected when the apparatus is in the mounted state and the image reading control means receives the image reading start command. Power supply control means for starting the supply and stopping the power supply to the image reading means by the power supply means when the image reading control means receives an image reading stop command. Image reading device.