JPS5934511B2 - detection device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a detection device having a simple configuration.

Conventionally, a printing device has a configuration in which, for example, a printing paper is passed through the soil of the type engraved on the outer periphery of a character wheel, and the type is struck through the printing paper by a printing hammer to print the desired type on the printing paper. In order to select the type or printing position provided on the wheel, a magnet m, for example, is placed on a disc B1 that rotates together with the character wheel A as a mark indicating the reference position of the character wheel A, as shown in Fig. 1. A magnet m2 is placed on the circumferential edge of the disk B, and serves as a mark to determine the character position of the type on the disk B2, which rotates during one rotation of the disk B1 corresponding to the number of character positions in one rotation of the character wheel A. , and detecting means (
(not shown), a detection device was provided to select the printed characters provided on the character wheel or the printing position. That is, in each printing device, detection means are independently arranged to make one judgment, that is, select a printed character or a printed position from a plurality of (in this case, two) marks. However, the detection means must take into account relatively high impedance, small signal output conditions, and noise resistance. Therefore, the configuration is complicated and requires expensive equipment. In view of the above-mentioned points, the present invention provides a detection device that can provide a mark on each of a plurality of members, detect the mark with a single detection means, and determine the character position, etc. Other objects will become clear from the following description of the embodiments given in conjunction with the drawings.

FIG. 2A is a plan view showing an embodiment of the detection device according to the present invention, which will be explained together with a side view shown at the beginning of FIG.

1 is a disk that rotates together with a character wheel of a printing device (not shown); 2 is a mark placed on the disk 1; for example, a magnet; 3
is a disk that rotates in relation to the disk 1, for example, corresponding to the number of characters provided on a character wheel (not shown), and a magnet 4 is also attached to this disk.

Note that the disks 1 and 3 are arranged so that their circumferential ends overlap. The magnets 2 and 4 are arranged at the circumferential ends of the disks 1 and 3 so as to face the detection means 5 provided between the disks 1 and 3, as shown in the opening of FIG. FIG. 3 shows an embodiment of the detection means 5 shown in FIG. It is composed of transistors 7 and 8. The operation of the embodiment configured as described above will be explained.

For example, the magnetic poles of the magnets 2 and 4 placed on the disks 1 and 3 are arranged so that they are the same polarity with respect to the detection means, for example, as shown in FIG. Then, when the magnets 2 and 4 provided on the discs 1 and 3 approach the detection means due to the rotation of the discs 1 and 3, the direction of the magnetic flux from the magnets 2 and 4 toward the Hall element changes, as shown in Fig. 5. As shown in the figure, the Hall element 6 generates induced voltages in different directions depending on the direction of the magnetic flux from the magnets 2 and 4, and the transistors 7 and 8 become conductive depending on the direction of the induced voltage, making it possible to obtain pulses from the collectors of the transistors. can.

Furthermore, if the polarities of the magnets with respect to the Hall element 6 are arranged to be different, for example, as shown in FIG. The detection means in such a case is as shown in FIG.
Width is increased and molded using . If the disks 1 and 3 are attached so that the magnetic poles of the magnets are in different directions with respect to the detection means 5, the Hall element generates a signal waveform as shown in FIG. 7 in response to the rotation of the disks 1 and 3. A signal waveform 10a is obtained, which is amplified and shaped by the transistor 10, and a signal waveform 10b is obtained.
Here, the magnets 2 and 4 provided on the disks 1 and 3 can be distinguished, for example, by the difference in moving speed of the magnets.
For example, the disc 1 can be attached to the character wheel of a printing device and rotated, and the disc 3 can be attached to a drive source motor etc. that rotates the character wheel to provide the above-mentioned difference in moving speed. If the motor is not directly driven, it always has a mechanism to reduce the rotation with a gear etc. when transmitting the rotation of the motor to the character wheel, and by attaching a disk to such a mechanism, the speed of movement can be varied. can. Such a difference in moving speed appears as a difference in pulse width in the output of the detection means, and the difference in pulse width can be distinguished by a counter or the like as a difference in the number of pulses. In addition, when the character wheel is directly driven by a motor, two discs are placed coaxially, a magnet is placed on one disc so that one reference pulse can be obtained, and a magnet is placed on one disc so that one reference pulse can be obtained from the other disc during one rotation of the disc. Magnets are arranged so as to obtain pulses equal to the number of characters on the letter wheel, and a detection means placed between two disks detects changes in the magnetic field of the magnet placed on the disk. may be detected. Note that if the circumferential edge of the disk is formed unevenly and the magnet is arranged in the center of the disk, it is not necessary to arrange a plurality of magnets on the circumferential edge, and the configuration can be simplified.

FIG. 8 shows another embodiment according to the invention. A disk 11 that is connected to a character wheel (not shown) and rotates integrally with the character wheel and a disk 12 that rotates corresponding to the number of characters provided on the character wheel during one rotation of the disk 11 are on the same plane. Detection means 1
Discs 11 and 1 are arranged at intervals that allow for the arrangement of disks 11 and 1.
Magnets 14 and 15 are arranged as marks on the peripheral edge of 2. The operation of this embodiment is similar to the previously described embodiment. Although the above example uses a Hall element, such a member is not limited to this, and may be a coil or other equivalent member.

It will be readily apparent to those skilled in the art that other electrical and optical detection means may also be used. As detailed above, the detection device according to the present invention is capable of detecting and discriminating a plurality of pieces of information using one detection means. Rather than supplying it to an integrated circuit and having it perform various controls,
Detecting and discriminating one type of signal and supplying it to the integrated circuit simplifies the configuration of the detection device, and also reduces the number of connections to the integrated circuit, reducing the number of terminals on the integrated circuit.

[Brief explanation of drawings]

Fig. 1 is a diagram explaining a conventional detection device, Fig. 2A is a plan view showing an embodiment of the detection device according to the present invention, Fig. 2 is a side view of the detection device shown in Fig. 4A, and Fig. 4A is a side view of the detection device shown in Fig. 4A. 3 is a circuit diagram of the detection means of the detection device according to the present invention, FIG. 4A is an explanatory diagram of the operation of the Hall element, FIG. FIG. 6 is a circuit diagram showing another embodiment of the detection means, and FIG.
The figures are a signal waveform diagram of the circuit shown in FIG. 6, FIG. 8A is a plan view showing another embodiment of the detection device according to the present invention, and FIG. , 4 is a magnet, and 5 is a detection means.

Claims (1)

[Claims] 1. In a printer that arranges a plurality of type on the surface of a rotating body and selects and prints the type, a first sub-rotating body that rotates in synchronization with the rotating body and a reference position of the rotating body are detected. a first signal generating means formed on the first sub-rotating body and generating a first signal; a second auxiliary rotating body that is provided at the second auxiliary rotating body and rotates in synchronization with the first auxiliary rotating body; a second signal generating means that is formed on the second auxiliary rotating body and generates a second signal; a detecting means disposed close to a circumferential end of the rotating body and a circumferential edge of the second sub-rotating body; A detection device configured to detect a signal and the second signal of the second signal generating means to select the plurality of printed characters.