JP2000241103A - Moving body detecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moving body detecting apparatus detecting the moving state of a moving body, with simple constitution of high reliability. SOLUTION: A moving body detecting apparatus 10 is equipped with two comb type electrodes 11 and 12 which are fixed and stretched parallel with the running direction, shown by an arrow mark B, of a moving body 19, and a contact 13 (13a or 13b) installed on the moving body 19. A first reference potential power source circuit 14 is connected with the electrode 11. A potential detecting circuit 15 and a second reference potential power source circuit 17 interposing a resistor circuit 16 are connected with branched connection lines of the electrode 12. A moving state detecting part Ct is connected with the potential detecting circuit 15. In accordance with movement of the moving body 19, the contact 13 intermittently electrically connects tooth parts of the electrodes 11 and 12. Pulse type potentials constituted of a first high reference potential and a second low reference potential appear on the electrode 12, and are detected as a pulse signal by the detecting circuit 15. The detecting part Ct counts change points of the pulse signal from a reference position, recognizes a present position of the moving body 19, measures the amount of movement and the time of an arbitrary section, and recognizes the moving velocity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving object detecting apparatus for detecting a moving state of a moving object with a simple structure.

[0002]

2. Description of the Related Art Conventionally, various moving object detecting devices have been put to practical use for detecting the moving state of a moving object. For example, in a serial printer, while a sheet is intermittently conveyed in a sub-scanning direction by a sheet feeding mechanism, a carriage equipped with a print head reciprocates in a main scanning direction during a pause of the intermittent conveyance, so that the print head moves on the sheet. Execute printing. An optical sensor is generally used to detect the movement position of the carriage of such a printer device.

FIG. 5 is a diagram schematically showing a configuration of a position detecting device using such an optical sensor. In FIG. 1, a carriage 1 includes a base 2 on which a print head (not shown) is mounted, a light emitting unit 3 and a light receiving unit 4 that constitute an optical sensor disposed on the base 2, and Power supply,
A ground line and a signal line 5 for driving control of the sensor and notification of detection from the sensor are provided. This carriage 1
Reciprocates in the main scanning direction indicated by the double-headed arrow A in the figure for printing.

On the other hand, a position detection pattern 6 is arranged on the printer main body side in parallel with the reciprocating direction of the carriage 1. The moving carriage 1 irradiates the detection pattern 6 with irradiation light from the light emitting unit 3 of the sensor, and the light beam illuminates the white area 7 and the black area 8 of the position detection pattern 6 alternately and sequentially. At this time, the light illuminating the white area 7 of the position detection pattern 6 is reflected and detected by the light receiving unit 4, while the light illuminating the black area 8 of the detection batterene 6 is not reflected, so that the light receiving unit 4 has no reflected light. Detection. This detection and non-detection information is notified to a control unit (not shown) via the signal line 5.

The control unit converts the information of the detection and non-detection into a pulse signal, and detects the moving amount of the carriage 1 by counting the number of pulses of the pulse signal. That is, the reference position (home position) of the carriage 1 is detected by another sensor or the like, and the number of pulses from the reference position is counted to calculate the amount of movement to recognize the current position.

[0006]

However, the above-described position detection method uses the carriage 1 which is a moving body, the light-emitting part of the sensor and the electronic parts of the light-receiving part, their power supply, ground wiring, and drive control of the sensor. And electrical connection of signal lines for detection notification from sensors is required. For this reason, there is a problem that the configuration of the electrical connection becomes complicated,
In addition, there is also a problem that such various occurrences of electrical connection with the movable component are not preferable in terms of reliability of operation control.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional circumstances,
An object of the present invention is to provide a moving object detection device that detects a moving state of a moving object with a highly reliable and simple configuration.

[0008]

The construction of the moving object detecting apparatus according to the present invention will be described below. The moving object detection device of the present invention includes:
A plurality of electrodes, at least one of which is laid in parallel to the traveling direction of the moving body, and at least two electrodes including the comb-shaped electrode among the plurality of electrodes provided so as to be movable integrally with the moving body; A contact for intermittently electrically connecting these electrodes by contacting the electrodes, a potential detecting means for detecting a potential of at least one of the electrodes contacted by the contact, and a potential detected by the potential detecting means. Moving state detecting means for detecting the moving state of the moving body based on a pulse signal composed of the potential.

The plurality of electrodes may be, for example, a pair of comb electrodes arranged so that the teeth of one comb electrode are positioned between the teeth of one comb electrode. Preferably, for example,
As described, it is preferable to be configured to be one linear electrode and at least one comb-shaped electrode arranged with the teeth facing the linear electrode.

The moving body is, for example, a carriage on which a recording head of a serial printer is mounted. Also, the contact may be, for example,
As described, the metal roller has a peripheral surface coated with conductive rubber.

Further, the moving state detecting means detects the position of the moving body, for example, as described in claim 6, and detects the speed of the moving body, for example, as described in claim 7.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is a diagram schematically illustrating a configuration of a moving object detection device according to the first embodiment, and FIGS. 1B and 1C are diagrams respectively illustrating contact members of the moving object detection device. FIG. 4D is a side sectional view showing a configuration example, and is a diagram showing a pulse signal output to a control unit (not shown) by the moving object detection device.

As shown in FIG. 1A, the moving object detecting device 1
0 denotes a double-headed arrow B in the figure of a moving body such as a carriage for reciprocating a print head of a serial printer, for example.
At least one laid in parallel to the running direction indicated by the symbol has a comb shape (in the example of the figure, both have a comb shape).
A plurality of (two in the example of FIG. 2) electrodes 11 and electrodes 12 are provided.

These electrodes (hereinafter also referred to as comb electrodes)
11 and 12 form a pair of electrodes arranged so that the teeth of the other comb-shaped electrode 12 are located between the teeth of one comb-shaped electrode 11. A first reference potential power supply circuit 14 is connected to the one electrode 11, and a connection line branches to the other electrode 12, and a second reference potential power supply circuit is connected via a potential detection circuit 15 and a resistance circuit 16. Circuits 17 are respectively connected. The potential detecting circuit 15 is connected to a moving state detecting unit Ct in a central control unit that controls the driving of the entire device on which the moving object detecting circuit is mounted. These electrodes 11, 12
The circuits 14 to 17 are formed on a substrate 18 shown in FIG.

In the direction shown by the arrow B in FIG. 1A in which these electrodes 11 and 12 are extended, as shown in FIG. 1B or FIG. Travels back and forth. This carriage 19 has this carriage 1
A contact 13 is provided so as to be movable integrally with the contact 9. The contact 13 is configured like a conductive roller 13a, for example, as shown in FIG.
As shown in the figure, the conductive sliding contact 13b is configured.

The conductive roller 13a is formed, for example, by coating a surface of a metal roller rotatably supported by a support shaft with conductive rubber, and the conductive sliding contact 13b is formed so that the surface is slidable. It is formed by covering with a metal foil or the like.
These contacts 13 (conductive roller 13a or conductive sliding contact 13b) roll or slide in response to the movement of the carriage 19 by receiving a driving force from a driving unit such as a motor (not shown). Then, as shown in FIGS. 7A to 7C, the teeth of the comb-shaped electrodes 11 and 12 are brought into contact, and the teeth of the electrodes 11 and 12 are intermittently electrically connected. Due to the intermittent electrical connection of the comb-shaped electrodes 11 and 12 based on the movement of the carriage 19, the potential of the electrode 12 becomes a pulse-like potential composed of a first reference potential and a second reference potential as shown in FIG. To form

That is, the electric resistance of the contact 13 shown in FIG. 1A is formed sufficiently smaller than the resistance value of the resistance circuit 16, and as a result, as shown in FIGS. As shown, when the contact 13 contacts the comb teeth of both the electrodes 11 and 12 to form a closed circuit, the potential of the electrode 12 becomes the same as that of the electrode 11. It is substantially equal to the first reference potential, which is the higher potential of one reference potential power supply circuit 14, while the contact 13 is
Ride on the teeth of either 1 or 12 comb,
When the connection between the electrodes 11 and 12 is cut off to form an open circuit, the potential of the electrode 12 is set to the second reference potential power supply circuit 1.
7 is equal to the second reference potential which is the lower potential.

The potential detection circuit 15 detects a pulse-like potential composed of the first reference potential and the second reference potential as a pulse signal shown in FIG. The movement state detection unit Ct includes:
The current position of the carriage 19 is calculated and recognized by counting the change point of the pulse signal from the reference position. In addition, the above-described counting can be executed from an arbitrary position, and the movement amount from the arbitrary position can be measured. Further, the moving speed and the moving speed of the current position can be calculated and recognized by measuring the moving amount and time from the immediately preceding position to the current position. Based on the detection data of these moving states, various related driving such as driving control of the moving body is controlled.

As described above, the configuration of the conductive roller 13a is such that the surface of a metal roller rotatably supported on a support shaft is coated with a low-resistance conductive rubber. This conductive rubber has a resistivity of 0.1 to
Those having a resistance of 100 Ωcm can be easily obtained.

Then, as described above, the electrodes 11 and 12
Is a closed circuit, the electrodes 11 and 12 are electrically connected by conducting a voltage in the order of conductive rubber, metal roller, and conductive rubber. At this time, the resistance value of the conductive roller 13a is determined when the contact area (first contact area) between the electrode 11 and the conductive roller 13a is equal to the contact area (second contact area) between the electrode 12 and the conductive roller 13a. Be minimized.

For example, the first and second contact areas are 0.25 mm × 10 mm and the conductive rubber coating thickness is 0.5
mm, the resistance of the conductive rubber is 100 Ωcm, and the resistance of the metal roller is almost 0 Ω, the resistance value of the conductive roller 13 a is 400 Ω. This is a sufficiently practical value. Actually, when the first contact area is not equal to the second contact area, the resistance value of the conductive roller 13a becomes 400
Therefore, the resistance value of the resistance circuit 16 is desirably set to a sufficiently large value, for example, about 100 kΩ.

Further, as shown in FIG.
When the conductive sliding contact 13b is used, there is a possibility that the contact between the metal foil of the conductive sliding contact 13b and the electrodes 11 and 12 is reduced due to wear. Therefore, in this case, the metal foil of the conductive sliding contact 13b and the electrodes 11 and 1
The use of a wear-resistant material for both 2 eliminates the above-mentioned fear.

FIG. 2 is a diagram schematically showing a configuration of a moving object detecting device according to the second embodiment. The moving body detection device 20 shown in the figure also has a pair of electrodes laid in parallel to the running direction of a moving body such as a carriage, for example, indicated by a double-headed arrow C in the drawing. However, in this case, one of the electrodes is a comb-shaped electrode 21 and the other electrode opposed thereto is a linear electrode 22. The comb-shaped electrode 21
The interval between the teeth is smaller than the interval between the teeth of the comb-shaped electrode 11 or 12 in FIG. More specifically, for example, the distance between the teeth of the comb electrode 11 and the teeth of the comb electrode 12 in FIG.

The first reference potential power supply circuit 14 is connected to the comb-shaped electrode 21 as in the case of FIG. 1A, the potential detection circuit 15, the resistance circuit 16, and the second reference potential power supply circuit 17 are connected to the straight electrode 22. As shown in FIG. A line contact conductive roller 23 is provided as a contact that moves integrally with the moving body and can make line contact with the electrode.

The line-contact conductive roller 23 is formed by reducing the thickness of the conductive rubber coating the surface of the metal roller to such a degree that the liner can substantially make line contact with the electrode. At one end is in constant contact with the linear electrode 22, and at the other end is intermittently in contact with the comb-shaped electrode 21. In this case, the electrodes 21 and 22 are provided by, for example, burying them in the substrate surface so that the step between the electrode surface and the substrate surface is negligibly small. Thus, similarly to the case of the configuration shown in FIG. 1A, the linear electrode 22 has a high potential of the first reference potential power supply circuit 14 similar to that shown in FIG. A reference potential,
The second reference potential power supply circuit 17 forms a pulse-like potential composed of a low second reference potential, which is detected by the potential detection circuit 15, and the detected potential is output to the moving state detection unit Ct as a pulse signal. You.

FIG. 3 is a diagram schematically showing a configuration of a moving object detecting device according to the second embodiment. In the moving object detection device 25 shown in FIG.
The two comb-shaped electrodes 26 and 27 which are laid in parallel with the running direction indicated by and face each other with their teeth facing each other are arranged. The opposing teeth of the comb-shaped electrodes 26 and 27 are arranged such that the arrangement pitch of the teeth is shifted by 1/4 phase in the extending direction. A linear electrode 28 is arranged to extend between the opposed teeth of the comb-shaped electrodes 26 and 27.

A first reference potential power supply circuit 29 is connected to the linear electrode 28. In addition, a connection line is branched to one of the comb electrodes 26 so that the second potential detection circuit 31 and the second
A second reference potential power supply circuit 33 is connected to each other via a resistor circuit 32 of the third type, and a connection line is also branched to the other comb-shaped electrode 27 to form a third potential detection circuit 35 and a third resistance circuit. Third reference potential power supply circuits 37 are connected to each other via. Then, the second and third potential detection circuits 31, 35
Are connected to the movement state detection unit Ct of the central control unit.

A line contact conductive roller 38 is provided as a contact that can move integrally with the moving body. Also in the case of this example, the line contact conductive roller 38 moves while the moving body is moving.
The center part is always in contact with the straight electrode 28. Then, both ends intermittently contact the comb-shaped electrodes 26 and 27, respectively.

As a result, the first reference potential, which is a high potential applied by the first reference potential power supply circuit 29 via the straight electrode 28 and the line contact conductive roller 38, is applied to one of the comb-shaped electrodes 26, The second potential, which is a low potential applied from the second reference potential power supply circuit 33 through the second resistance circuit 32
A pulse-like potential composed of the reference potential is formed, and this is detected by the second potential detection circuit 31.

The other comb-shaped electrode 27 has a first reference potential, which is a high potential applied by a first reference potential power supply circuit 29 via a linear electrode 28 and a line contact conductive roller 38, and a third reference potential. A pulse-like potential composed of the third reference potential, which is a low potential applied from the third reference potential power supply circuit 37 via the resistor circuit 36, is formed, and this is detected by the third potential detection circuit 35.

The pulse signal detected by the second potential detecting circuit 31 and the pulse signal detected by the third potential detecting circuit 35 are generated by the opposing teeth of the comb electrodes 26 and 27 as described above. Since the mutual positions are shifted in the moving direction of the moving body by １ ／ phase of the pitch, the rising and falling phases of the pulse appear to be shifted by ４ phase from each other.
For example, now the line contact conductive roller 38 is
Assuming that the connection between the three electrodes 26, 27 and 28 indicated by 8 'is open, the second potential detection circuit 31 is detecting the low second reference potential and the third potential detection The circuit 35 is also detecting the low third reference potential.

From this state, assuming that the moving body, that is, the line contact conductive roller 38 has moved to the left as shown by the arrow D in the figure, first, the second potential detecting circuit 31 outputs the high potential of the first reference potential. Detect rising. Subsequently, with a 相 phase delay, the third potential detection circuit 35 detects the first reference potential having a higher potential. On the other hand, assuming that the line contact conductive roller 38 has moved rightward as indicated by the arrow E in the figure from the position indicated by the dashed line 38 'in the figure, first, the third potential detection circuit 35 1 Detect rising of reference potential,
Next, the second potential detection circuit 31 detects the higher first reference potential with a て phase delay.

As described above, the rising edge of the pulse signal is mutually detected with a 1/4 phase delay, so that the moving position can be detected at finer intervals, and the detecting sequence of the rising edge of the pulse signal is determined in the moving direction. The moving body detection unit Ct can easily recognize in which direction the moving body is currently moving.

As described above, according to the present embodiment, the moving direction can be detected in addition to the moving amount, the position, and the moving speed of the moving body. This makes it possible to determine the direction of the chattering of the detected potential generated when the contact is in contact with the electrode, cancel the position detection error caused by the direction, and improve the position detection accuracy.

FIG. 4 is a diagram schematically showing the configuration of a moving object detecting device according to the fourth embodiment. The moving body detection device 40 shown in the figure is laid in parallel to the traveling direction of the moving body shown by the arrow F or G in the figure, and faces the linear electrode 41 with the tooth portion of the deformed interval facing the straight electrode 41. Comb electrode 4
2 are arranged. The teeth of the comb-shaped electrode 42 are arranged in the direction of arrow F in the figure such that the pitch of the teeth is changed from one phase to two phases to three phases to one phase in a circulating manner. In other words, in the direction of arrow G in the figure, the pitch of the tooth portion is one phase → 3
It is arranged in the form of phase → 2 phase → 1 phase, circulating and deforming.

The first reference potential power supply circuit 14 shown in FIG. 1A is connected to the linear electrode 41. The comb-shaped electrode 42 also has the potential detection circuit 1 shown in FIG.
5, the resistance circuit 16 and the second reference potential power supply circuit 17 are connected. The line contact conductive roller 43 is provided as a contact that can move integrally with the moving body.

During the movement of the moving body, the line-contact conductive roller 43 also constantly contacts the linear electrode 43 at one end and intermittently contacts the comb-shaped electrode 42 at the other end. The time interval of the intermittent contact is such that when the moving body moves in the direction of arrow F in the figure, it circulates in the order of 1 phase → 2 phase → 3 phase → 1 phase. From the reference potential power supply circuit 14 to the linear electrode 41 and the line contact conductive roller 4
The first reference potential of a high potential applied via 3 becomes a short pulse signal and appears at time intervals of circulating 1 phase → 2 phase → 3 phase → 1 phase.

On the other hand, when the moving body moves in the direction of arrow G in the figure, the time interval of the intermittent contact between the line-contact conductive roller 43 and the comb-shaped electrode 42 is 1 phase → 3 phase → 2 phase → 1 phase. Interval. Accordingly, in this case, a short pulse signal of the first reference potential having a high potential appears on the comb-shaped electrode 42 at a time interval of circulating 1 phase → 3 phases → 2 phases → 1 phase. The potential detection circuit 15 detects the pulse potential of this deformation cycle,
This detected potential is output as a pulse signal to the moving state detection unit Ct.

The moving state detecting unit Ct has a pulse signal having a cycle of circulating 1 phase → 2 phase → 3 phase → 1 phase or circulating 1 phase → 3 phase → 2 phase → 1 phase. Depending on the period, the moving direction of the moving body can be distinguished, and each period of the deformation cycle of the pulse signal is divided by the reference pulse to accurately recognize the current position or moving speed of the moving body. Can be.

In any of the first to fourth embodiments, if a position detection error due to chattering in detecting a pulse potential (pulse signal) is considered in any case, the position detection error is canceled. For this purpose, it is preferable to measure the time between the changing points of the pulse signal, and not to count the changing points if the measured time is shorter than a predetermined time.

When the measured time is shorter than a predetermined time, the position detection is determined to be an error by judging that there is an abnormality in the moving drive of the moving body when the counted value exceeds the predetermined value. It may be.

[0042]

As described above in detail, according to the present invention, since only the conductive contact is provided on the movable body for detecting the position, the light emitting portion and the light receiving portion of the optical sensor are not provided. The electrical connection of the electronic components and their power supply, ground circuit, signal line, etc. is not required, thereby reducing the mechanical and electrical load of the moving body, and therefore moving with a highly reliable and simple configuration. It is possible to provide a moving object detection device that detects a moving state of a body.

[Brief description of the drawings]

FIG. 1A is a diagram schematically illustrating a configuration of a moving object detecting device according to a first embodiment, and FIGS. 1B and 1C are side cross-sectional views illustrating a configuration example of a contact of the moving object detecting device. (D) is a diagram showing a pulse signal output by the moving object detection device.

FIG. 2 is a diagram schematically illustrating a configuration of a moving object detection device according to a second embodiment.

FIG. 3 is a diagram schematically illustrating a configuration of a moving object detection device according to a third embodiment.

FIG. 4 is a diagram schematically illustrating a configuration of a moving object detection device according to a fourth embodiment.

FIG. 5 is a diagram schematically showing a configuration of a conventional position detecting device using an optical sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carriage 2 Base part 3 Optical sensor light-emitting part 4 Optical sensor light-receiving part 5 Signal line 6 Position detection pattern 7 White area 8 Black area 10 Moving object detection device 11 of the first embodiment 11, 12 Comb electrode 13 Contact 13a conductive roller 13b conductive sliding contact 14 first reference potential power supply circuit 15 potential detection circuit 16 resistor circuit 17 second reference potential power supply circuit 18 substrate 19 carriage 20 moving object detection device 21 of second embodiment 21 comb shape Electrode 22 Linear electrode 23 Line contact conductive roller (contact) 25 Moving object detecting device 26, 27 Comb electrode 28 Linear electrode 29 First reference potential power supply circuit 31 Second potential detection circuit 32 2 resistance circuit 33 second reference potential power supply circuit 35 third potential detection circuit 36 third resistance circuit 37 third reference potential power supply circuit 38 line connection Tactile conductive roller (contact) 40 Moving object detection device of fourth embodiment 41 Linear electrode 42 Comb-shaped electrode 43 Line contact conductive roller (contact) Ct Moving state detection unit

Claims (7)

[Claims] At least one electrode laid in parallel with a traveling direction of a moving body has a plurality of comb-shaped electrodes, and the plurality of electrodes are provided so as to be movable integrally with the moving body and include the comb-shaped electrode among the plurality of electrodes. A contact for contacting at least two electrodes and intermittently electrically connecting these electrodes; a potential detecting means for detecting a potential of at least one of the electrodes contacted by the contact; A moving object detecting device, comprising: moving state detecting means for detecting a moving state of the moving object based on a pulse signal composed of a potential detected by the detecting means. 2. The method according to claim 1, wherein the plurality of electrodes are a pair of comb electrodes arranged so that the teeth of the other comb electrode are located between the teeth of one comb electrode. Moving object detection device. 3. The moving body according to claim 1, wherein the plurality of electrodes are a single linear electrode and at least one comb-shaped electrode disposed with a tooth portion facing the linear electrode. Detection device. 4. The moving object detecting apparatus according to claim 1, wherein the moving object is a carriage on which a recording head of a serial printer is mounted. 5. The moving body detecting device according to claim 1, wherein the contact is a metal roller having a peripheral surface covered with conductive rubber. 6. The moving object detecting apparatus according to claim 1, wherein the moving state detecting means detects a position of the moving object. 7. The moving object detecting device according to claim 1, wherein the moving state detecting means detects a speed of the moving object.