JP2020181115A - Horn control device - Google Patents

Abstract

To provide a horn control device capable of controlling a horn to generate different tones.SOLUTION: In a horn control device 10 which controls a sounding of a horn 20 including a coil 21, a fixing member 24 which is arranged in the coil 21 and constitutes an electromagnet when the coil 21 is energized, a movable member 23 which is arranged so as to be able to vibrate within a range until it collides with the fixing member 24 and can be displaced toward the fixing member 24 by a magnetic force of the electromagnet, and a mechanical contact point 22 which is normally closed and is urged to open when the movable member 23 is displaced more than a certain distance before colliding with the fixing member 24, a control unit 1 is provided which, by applying a voltage pulse train to the coil 21, causes the horn 20 to sound by duty driving, and the applied pulse width is set for the contact point 22 to keep a closed state by keeping displacement less than the certain distance when the movable member 23 vibrates.SELECTED DRAWING: Figure 1

Description

The present invention relates to a horn control device capable of controlling a horn to generate various tones.

In the vehicle anti-theft system disclosed in Patent Document 1, a warning sound is output by a buzzer when the vibration detected in the vehicle of a motorcycle exceeds a predetermined value.

Japanese Unexamined Patent Publication No. 2006-306136

Various sounds such as notifications, instructions, warning sounds, etc. are assumed to be required in the vehicle, but in the above-mentioned conventional technology, the buzzer is supposed to emit a warning sound for theft prevention, and a warning is given. In order to generate sounds for other purposes (for example, sounds for notifying the vehicle condition) that are composed of tones different from the sounds, it is necessary to install a separate sound generator, which increases the cost. There was a challenge.

For example, a vehicle is provided with a horn for a horn, and it is desired to use this horn to generate various sounds.

In view of the above problems of the prior art, an object of the present invention is to provide a horn control device capable of controlling a horn to generate different sounds.

In order to achieve the above object, the present invention
With the coil (21)
A fixing member (24) arranged in the coil (21) and forming an electromagnet when the coil (21) is energized,
A movable member (23) that is oscillated within a range (DB) until it collides with the fixed member (24) and is displaceable toward the fixed member (24) by the attractive force of the electromagnet.
A contact (22) connected to the coil (21), which is always closed and has a distance (DA) greater than a certain distance (DA) before the movable member (23) collides with the fixing member (24). A mechanical contact (22) that is urged to open when it is displaced significantly,
In the horn control device (10) that controls the sounding of the horn (20) by energizing the horn (20) provided with the above.
A control unit (1) for duty-driving and sounding the horn (20) by applying a voltage pulse train to the coil (21) is provided.
The pulse width in the applied voltage pulse train is set so that the contact (22) is kept in a closed state by keeping the displacement when the movable member (23) vibrates is less than the fixed distance (DA). The first feature is that it is present.

In addition, the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
The second feature is that the pulse width for driving is set to less than 1/2 of the fundamental period, which is the reciprocal of the fundamental frequency of the horn (20), at any pulse frequency.

In addition, the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
The third feature is that the pulse width for driving is set to 1/3 or less of the fundamental period, which is the reciprocal of the fundamental frequency of the horn (20), at any pulse frequency.

In addition, the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
When the pulse frequency is set lower than the fundamental frequency in the threshold value determination, the pulse width for driving is set to 1/3 or less of the fundamental period which is the reciprocal of the fundamental frequency of the horn (20). Cage,
When the pulse frequency is not set lower than the fundamental frequency in the threshold value determination, the fourth feature is that the pulse width for driving is set to less than 1/4 of the fundamental period.

In addition, the present invention
A fifth feature is that the control unit (1) and the horn (20) are connected in parallel to the battery (B) to provide a common power supply voltage by the battery (B). To do.

In addition, the present invention
A voltage detection unit (5) for detecting the voltage of the battery (B) that provides a power supply voltage for driving the horn (20) is further provided.
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
The sixth feature is that the smaller the voltage detected by the voltage detection unit (5) is, the longer the pulse width for driving is set at any pulse frequency.

Of the present invention
With the coil (21)
A fixing member (24) arranged in the coil (21) and forming an electromagnet when the coil (21) is energized,
A movable member (23) that is oscillated within a range (DB) until it collides with the fixed member (24) and is displaceable toward the fixed member (24) by the attractive force of the electromagnet.
A contact (22) connected to the coil (21), which is always closed and has a distance (DA) greater than a certain distance (DA) before the movable member (23) collides with the fixing member (24). A mechanical contact (22) that is urged to open when it is displaced significantly,
In the horn control device (10) that controls the sounding of the horn (20) by energizing the horn (20) provided with the above.
A control unit (1) for duty-driving and sounding the horn (20) by applying a voltage pulse train to the coil (21) is provided.
The pulse width in the applied voltage pulse train is set so that the contact (22) is kept in a closed state by keeping the displacement when the movable member (23) vibrates is less than the fixed distance (DA). According to the first feature of being
By vibrating the horn (20) in a range in which the contact (22) is kept closed, the horn (20) is made to sound, which is different from the case where the movable member (23) collides with the fixed member (24). By generating a timbre in the horn (20), a different timbre can be generated by the horn (20).

Of the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
According to the second feature that the pulse width for driving is set to less than 1/2 of the fundamental period, which is the reciprocal of the fundamental frequency of the horn (20), at any pulse frequency.
By setting the pulse width for driving to less than 1/2 of the basic period, the pulse width in the applied voltage pulse train is less than the constant distance (DA) when the movable member (23) vibrates. Can be kept.

Of the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
According to the third feature that the pulse width for driving is set to 1/3 or less of the fundamental period which is the reciprocal of the fundamental frequency of the horn (20) at any pulse frequency.
By setting the pulse width for driving to 1/3 or less of the basic period, even if the horn (20) has a characteristic variation within a certain control range, the pulse width in the applied voltage pulse train can be set. The displacement when the movable member (23) vibrates can be kept less than the constant distance (DA).

Of the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
When the pulse frequency is set lower than the fundamental frequency of the horn (20) in the threshold value determination, the pulse width for driving is set to 1/3 or less of the fundamental period which is the reciprocal of the fundamental frequency. Cage,
According to the fourth feature, when the pulse frequency is not set lower than the fundamental frequency in the threshold value determination, the pulse width for driving is set to less than 1/4 of the fundamental period. ,
The pulse frequency is lower than the fundamental frequency because the pulse width for driving is set to 1/3 or less of the fundamental period, which is the reciprocal of the fundamental frequency, so that the horn (20) has characteristics within a certain control range. Even if there are variations, it prevents the resonance state accompanied by collision,
When the pulse frequency is not lower than the fundamental frequency (including the case where it is higher than the fundamental frequency), the pulse width for driving is set to less than 1/4 of the fundamental period which is the reciprocal of the fundamental frequency.
In either case, the pulse width for driving is set to satisfy at least one-third of the basic period, thereby ensuring a certain margin and then the pulse in the voltage pulse train to be applied. The width can be such that the displacement when the movable member (23) vibrates is kept less than the constant distance (DA).

Of the present invention
The fifth feature is that the control unit (1) and the horn (20) are connected in parallel to the battery (B) to provide a common power supply voltage by the battery (B). According to
Both the control unit (1) and the horn (20) can be driven by a common battery (B).

Of the present invention
A voltage detection unit (5) for detecting the voltage of the battery (B) that provides a power supply voltage for driving the horn (20) is further provided.
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
According to the sixth feature, that the smaller the voltage detected by the voltage detection unit (5) is, the longer the pulse width for driving is set at any pulse frequency.
Even if the power supply voltage of the battery (B) fluctuates, the sound pressure of the horn (20) can be kept constant.

It is a figure which shows the structure (circuit structure and function structure) of the horn control device which controls the drive of a horn which concerns on one Embodiment. It is a figure for demonstrating the outline of the mechanical structure of the horn by showing the cross-sectional structure of the horn which concerns on one Embodiment. It is a flowchart when the horn control device controls the sounding of a horn in the first embodiment. It is a graph which shows the schematic example of the circuit waveform when the horn control device controls the sounding of a horn in 1st Embodiment. It is a flowchart when the horn control device controls the sounding of a horn in the second embodiment. It is a graph of the sound pressure and the pulse width when the horn is sounded by the second embodiment by changing the pulse frequency in the range of about 200Hz to 2000Hz under the common setting. It is a graph which shows the schematic example of the circuit waveform in a part of the experimental example of FIG. It is a figure which shows the schematic example which changes a pulse width.

FIG. 1 is a diagram showing a configuration (circuit configuration and functional configuration) of a horn control device 10 that controls the sound generation of the horn 20 according to one embodiment. The horn control device 10 includes a battery B, a regulator 6, a control unit 1, a switch element SE1, a first switch SW1 and a second switch SW2 as a main configuration, and controls driving of a horn 20 including a coil 21 and a contact 22. .. The horn 20 may also be provided in the horn control device 10. The horn control device 10 and the horn 20 may be installed in a vehicle such as a motorcycle.

The control unit 1 can be configured to include a processor such as a CPU and a memory as hardware, and each has a functional configuration realized by the processor reading and executing a predetermined program stored in the memory. A drive unit 2, a current detection unit 4, and a voltage detection unit 5 are provided.

By connecting the control unit 1 and the horn 20 in parallel to the battery B, the battery B provides the control unit 1 with an operating voltage and also provides a drive voltage when the horn 20 blows. That is, the control unit 1 and the horn 20 are driven by a common battery (power supply) B. Here, by connecting the regulator 6 between the battery B and the control unit 1, the voltage adjusted by the regulator 6 is provided as the operating voltage of the control unit 1. For example, the regulator 6 may step down the voltage of the battery B and provide it to the control unit 1.

In the present embodiment, the switch element SE1 and the horn 20 are connected in series to the high voltage side (opposite side to the ground) of the battery B in this order. The switch element SE1 is on / off controlled by the control unit 1, so that the horn 20 is driven by the power supply voltage of the battery B, and the horn 20 is driven.

As will be described in detail later, when the control unit 1 receives the first input by turning on the first switch SW1 by the user (for example, the occupant of the motorcycle), the control unit 1 first implements the horn 20. In the embodiment, when the control unit 1 receives the second input by turning on the second switch SW2 while driving the horn to sound (sound as a horn), the control unit 1 sets the horn 20 in the first embodiment. It is driven to sound (pronounce as a buzzer) in the second embodiment different from the above. Both the first switch SW1 and the second switch SW2 can be provided as mechanical switches that accept on operations by the user.

In the present embodiment, the switch element SE1 is configured as an N-type FET (N-type field effect transistor).

The source S1 of the switch element SE1 (N-type FET) is connected to the horn 20, the drain D1 is connected to the battery B, and the gate G1 is connected to the drive unit 2. As will be described later, the drive unit 2 controls the on / off of the gate G1 to drive the horn 20 by the battery B to make a sound or sound.

One end of the horn 20 is connected to the switch element SE1 and the other end is grounded. FIG. 2 is a diagram for explaining an outline of the mechanical configuration of the horn 20 by showing the cross-sectional configuration of the horn 20 according to the embodiment. The horn 20 includes a contact assembly 220 composed of a coil 21, a contact 22 composed of a first contact 22A and a second contact 22B, a rigid stay 22C and a spring plate 22D, a movable shaft (movable member) 23, and a fixed shaft (fixed shaft). It includes a fixing member) 24, a diaphragm 25, a resonator (resonator) 26, a case 30, and a stay 31.

The case 30 houses the diaphragm 25, the movable shaft 23, the fixed shaft 24, and the contact assembly 220. By fixing the case 30 to the stay 31, the horn 20 can be attached to a motorcycle or the like via the stay 31. By connecting the case 30 to the horn control device 10, the horn 20 and the horn control device 10 are electrically connected.

The diaphragm 25 is fixed to the case 30 so as to close the opening of the case 30 with a ring-shaped fixing member. The diaphragm 25 is formed as, for example, a disk-shaped thin metal plate. A movable shaft 23 is fixed to the center of the diaphragm 25 together with a washer and a resonator 26 by caulking.

Both the movable shaft 23 and the fixed shaft 24 are made of a magnetic material such as iron and are arranged coaxially with each other. The movable shaft 23 is configured to vibrate on the same axis, and when the amplitude is large, it collides with the fixed shaft 24 fixed to the bottom of the case 30. By arranging the fixed shaft 24 in the coil 21, the coil 21 and the fixed shaft 24 form an electromagnet, and the movable shaft 23 is driven on the coaxial by the magnetic force (attracting force) thereof.

In the contact assembly 220, the first contact 22A is fixed to the rigid body stay 22C so as not to be displaced with respect to the case 30, and the second contact 22B is fixed to the spring plate 22D to the case 30. It is fixed so that it can be displaced. The second contact 22B is elastically urged against the first contact 22A by the spring plate 22D, so that the contact 22 (first contact 22A and second contact 22B) is always closed.

Due to the attractive force of the electromagnet, the movable shaft 23 of the fixed shaft 24 is placed on the same axis from a stationary position (when the horn 20 is not sounding, that is, when the coil 21 is not energized and the electromagnet is not configured). When it moves toward the direction by the first distance DA (not shown), it comes into contact with the spring plate 22D, and when it moves further than the first distance DA, the spring plate 22D is elastically deformed toward the fixed shaft 24 side. As a result, the first contact 22A and the second contact 22B are separated from each other to open the contact 22, and the contact 22 is arranged so as to collide with the fixed shaft 24 when moved by the second distance DB (not shown) from the stationary position. Has been done. Here, "0 <DA <DB".

That is, the x-axis (not shown) representing the position of the movable shaft 23, where the stationary position of the movable shaft 23 is the origin (x = 0) on the same axis and the direction toward the fixed shaft 24 on the same axis is positive. ), The case related to the open / closed state of the contact 22 can be classified as follows according to the position x of the movable shaft 23.

(In the first case) When x <DA, the movable shaft 23 and the spring plate 22D are separated from each other, and the contact point 22 is closed. (This includes the case where the movable shaft 23 is located on the side away from the fixed shaft 24 at "x <0".)
(In the second case) When x = DA, the movable shaft 23 and the spring plate 22D are in contact with each other without urging, and the contact point 22 is closed.
(In the third case) When DA <x <DB, the movable shaft 23 urges the spring plate 22D to elastically deform it toward the position of the fixed shaft 24, and the contact 22 is open.
(In the fourth case) When x = DB, the movable shaft 23 urges the spring plate 22D to elastically deform it, and the movable shaft 23 collides with the fixed shaft 24, and the contact 22 is open. (Since the fixed shaft 24 is fixed to the case 30, the movable shaft 23 does not move to a position where “x> D2”.)

Hereinafter, the first embodiment (when the first switch SW1 is turned on) relating to the control for driving the horn control device 10 to make the horn 20 sound, and the control for driving the horn 20 to sound different from this, the first embodiment. Two embodiments (when the second switch SW2 is turned on) will be described in order.

FIG. 3 is a flowchart when the horn control device 10 controls the horn 20 to sound in the first embodiment. In step S11, when the user turns on the first switch SW1, it is determined whether or not the first input has been input to the control unit 1, and if it has been input, the process proceeds to step S12, and if it has not been input, step S11 Return to.

In step S12, the drive unit 2 applies a voltage to the gate G1 of the switch element (N-type FET) SE1 to turn on the switch element SE1 (that is, make the source S1 and the drain D1 conductive). The process proceeds to step S13. Here, in the first embodiment, the drive unit 2 continuously turns on the switch element SE1 by applying a DC voltage to the gate G1.

In this way, the horn 20 is driven by the DC voltage of the battery B and sounds because the switch element SE1 is kept on until the sounding stop control described later is performed after step S12. The outline of the operation of the horn 20 at the time of this sounding is that the following states (1) to (6) are repeated in this order.

(1) The coil 21 is energized. (2) The coil 21 and the fixed shaft 24 function as electromagnets to attract the movable shaft 23 toward the fixed shaft 24 by magnetic force and accelerate it. (3) Immediately before the movable shaft 23 collides with the fixed shaft 24, the movable shaft 23 pushes the spring plate 22D to open the contact 22 and cut off the current of the coil 21. (4) The movable shaft 23 collides with the fixed shaft 24 by inertia, the impact of the collision is transmitted to the resonator 26, the impact sound is increased by the resonator 26, and the horn 20 blows. (5) The movable shaft 23 returns to the resting position (the position of "x = 0" described above) due to the repulsive force due to the collision and the elastic force of the diaphragm 25. (6) At a position where the movable shaft 23 is in the process of returning to the stationary position, the contact 22 closes and energization starts again, returning to the state (1).

Regarding the position x of the movable shaft 23, the above states (1) and (2) correspond to the above-mentioned "x <DA" in the first case, and the states (3) and (5) are the third. Corresponds to "DA <x <DB", corresponds to "x = DB" when the state (4) is the fourth, and corresponds to "x = DA" when the state (6) is the second.

As described above, in the first embodiment, the horn 20 blows at its fundamental frequency. That is, the fundamental frequency is the number of times the contact 22 opens and closes per second by periodically repeating the above states (1) to (6), and the number of times the movable shaft 23 collides with the fixed shaft 24. is there. It should be noted that the sound emitted by the horn 20 includes components other than the fundamental frequency due to the fact that the resonator 26 emits a metal resonance sound due to the collision, and is suitable as the sound of a sound device such as a motorcycle. Become. The fundamental frequency is determined as a value peculiar to the horn 20 by the elastic modulus of the diaphragm 25, the mass of the movable shaft 23, the inductance of the coil 21, and the like.

In step S13, the control unit 1 determines whether or not a predetermined sounding end determination has been obtained, and if so, proceeds to step S14, and if not, returns to step S13 until this determination is obtained. stand by. This determination condition may be any condition suitable for the use of the horn 20, and may be determined by whether or not a certain time has elapsed since the horn 20 started to sound, or when used as a horn. If so, the determination may be made based on the fact that the first switch SW1 is turned off.

In step S14, the current detection unit 4 starts detecting the current (horn current) flowing through the horn 20, and then proceeds to step S15. In the configuration of FIG. 1, the current detection unit 4 detects the horn current at the location of the source S1, but it may be detected at other locations. For example, the current may be detected at the drain D1.

In step S15, it is determined whether or not the value of the horn current detected by the current detection unit 4 has become zero, and if it is zero, the process proceeds to step S16, and if it is not zero, the process proceeds to step S15. Return and wait until a zero judgment is obtained.

In step S16, the drive unit 2 releases the DC voltage applied to the gate G1 of the switch element SE1 to turn off the switch element SE1 to stop the sounding of the horn 20, and the above flow of FIG. 3 ends. To do.

FIG. 4 is a graph showing a schematic example of a circuit waveform when the horn control device 10 controls the horn 20 to sound in the first embodiment. In FIG. 4, the voltage V (G1) of the gate G1, the voltage V (S1) of the source S1, and the current I (D1) of the drain D1 are shown in order from the top on the graph with the horizontal axis as the common time. ..

In FIG. 4, the time t1 is the time when the switch element (N-type FET) SE1 is turned on in step S12, the time t2 is a fixed time after the time t1, and the sounding end determination is obtained in step S13 and step S14. Is the time when the detection of the horn current is started at, and at time t3, it is detected that the horn current has become zero (that is, a positive judgment is obtained in step S15, and then in step S16). It is the time when the sound stopped. In FIG. 4, it can be seen that the fundamental frequency of the horn 20 is about 400 Hz from the horn current (current I (D1) of the drain D1) which is a pulsating current, and that the noise when the sound is stopped is suppressed. Can be done. Here, by turning off the switch element SE1 when the current detection unit 4 confirms that the horn current becomes zero, it is possible to suppress noise when the sounding is stopped.

FIG. 5 is a flowchart when the horn control device 10 controls the sound of the horn 20 in the second embodiment. In step S31, the user turns on the second switch SW2 to determine whether or not the second input has been input to the control unit 1, and if it has been input, the process proceeds to step S32, and if not, step S31. Return to.

In step S32, the drive unit 2 starts a process of intermittently turning on the switch element SE1 by continuously applying a voltage to the gate G1 of the switch element (N-type FET) SE1 as a pulse train, and then in step S33. Proceed to. Here, in the second embodiment, the drive unit 2 duty-drives the switch element SE1 to intermittently turn it on by applying a voltage to the gate G1 as a pulse train having a predetermined cycle and a predetermined duty. The details will be described later.

In step S33, the control unit 1 determines whether or not a predetermined sounding end determination has been obtained, and if so, proceeds to step S34, and if not, returns to step S33 until this determination is obtained. stand by. (While this standby is in progress, the horn 20 continues to sound.) This determination condition may be any condition suitable for the intended use of the horn 20, and is constant after the horn 20 starts sounding. It may be determined by whether or not the time has passed, or it may be determined by turning off the second switch SW2.

In step S34, the drive unit 2 ends the duty drive of the switch element SE1, cancels the application of the pulse train to the gate G1 and turns off the switch element SE1, so that the above flow of FIG. 5 ends. With the end of the duty drive in step S34, the sound of the horn 20 also ends.

Hereinafter, details of the duty drive by the drive unit 2 in the second embodiment and the mode of sounding of the horn 20 by the duty drive will be described. In the duty drive by the drive unit 2, the gate G1 is turned on in a pulse train having a predetermined cycle and a predetermined pulse width, so that the voltage applied by the battery B to the horn 20 (coil 21) is also a pulse train having the predetermined cycle and the predetermined pulse width. Is to be. By setting various predetermined periods and predetermined pulse widths in advance, the buzzer sound of the horn 20 can be set to various frequencies and sound pressures. However, the following common restrictions are satisfied in both the predetermined period and the predetermined pulse width setting.

(Common constraints)
Whenever the movable shaft 23 is driven and vibrates, its position x is at "x <DA" in the first case described above, so that the contact 22 is kept in a closed state, and is therefore movable. A predetermined period (or a predetermined frequency) and a predetermined pulse width are set so that the shaft 23 does not collide with the fixed shaft 24.

Due to the above common restrictions, in the second embodiment, the movable shaft 23 (and the diaphragm 25 and the resonator 26 fixed to the movable shaft 23) vibrate in a form close to a simple vibration in this predetermined cycle. Therefore, unlike the first embodiment accompanied by a collision, in the second embodiment, the horn 20 can be sounded with a soft tone, for example, a notification sound when an occupant performs various systematic operations in a motorcycle. It is possible to obtain a tone suitable for use in.

Specifically, under the above-mentioned common constraints, various settings can be made for the period (or frequency) and pulse width of the pulse train in the second embodiment under the following common settings, and the horn. The frequency and sound pressure of 20 voices can be selected from a wide variety.

(Common setting)
The common setting is the period (that is, the reciprocal of the fundamental frequency) at the fundamental frequency of the horn 20 regardless of the period (or frequency) of the pulse train set by being selected within a certain range. The pulse width is set to be smaller than 1/2 of).

That is, the possibility that the above common constraint (maintaining the closed state of the contact 22) is not satisfied is most likely to occur when the period of the applied pulse train is set to match or be close to the basic period (hereinafter,). , Called the worst case). In this worst case, if the pulse width is set as a value of 1/2 or more of the basic period, the applied voltage is not direct current, but as a result, the resonance state similar to that of the first embodiment is obtained, and the movable shaft 23 will collide with the fixed shaft 24. This is because, in the waveform of the horn current in the first embodiment, the ratio of the current flowing, that is, the ratio of the contact 22 in the closed state is a little over 1/2. Therefore, by always setting the applied pulse width to be smaller than 1/2 of the basic period including the worst case, the movement of the movable shaft 23 different from that of the first embodiment is realized, and the above-mentioned movement is realized. It is possible to realize the sounding in the second embodiment that satisfies the common constraint.

In the worst case described above, if the pulse width is set to a value close to 1/2 of the basic period, it is the same as that of the first embodiment depending on the characteristic variation of the horn 20 (the variation within a certain control range). The movable shaft 23 may collide with the fixed shaft 24 due to resonance. Alternatively, even if the movable shaft 23 does not always collide with each vibration, the contact 22 may not be closed occasionally, and the movable shaft 23 may vibrate irregularly, resulting in muddy pronunciation. .. Therefore, in the worst case (when the pulse frequency is determined to be close to the fundamental frequency by the threshold determination) and / or the pulse so as to more reliably satisfy the above common constraint (maintaining the closed state of the contact 22). If the frequency is lower than the fundamental frequency in the threshold judgment, set the pulse width to 1/3 or less of the fundamental cycle, and in other cases, set the pulse width to less than 1/4 of the fundamental cycle. You may.

That is, when the set pulse frequency is lower than the basic frequency in the threshold judgment, the pulse width is set to 1/3 or less (may be less than 1/3) of the basic period, and in other cases (set pulse frequency). Is not lower than the fundamental frequency in the threshold determination, that is, when the high pulse frequency side includes the short pulse period side), the pulse width is less than 1/4 (or 1/4 or less) of the basic period. You may set it.

Alternatively, the pulse width may be set to be 1/3 or less (or less than) of the basic period at all times regardless of the set pulse frequency.

FIG. 6 is a graph of sound pressure and pulse width when the horn 20 is blown according to the second embodiment by changing the pulse frequency in a range of approximately 200 Hz to 2000 Hz under the above common settings. The lines L1, L2 and L3 in the graph show the sound pressure at each pulse frequency (applied frequency) when the voltage of the battery B is 15V, 13.5V and 10V, respectively, and the line L4 in the graph is a common setting at each pulse frequency. It shows the pulse width.

The example of FIG. 6 is an example in which the sound pressure is set to be kept substantially constant in the range of approximately 200 Hz to 2000 Hz.

In the example of FIG. 6, the fundamental frequency of the horn 20 is 400 Hz, and therefore the fundamental period is 2.5 ms. In this case, according to the above common setting, the pulse width may be set to less than 1.25 ms, which is 1/2 of the basic period, regardless of the set pulse frequency, and the pulse width is set as shown in the example of FIG. Has been done. In the example of FIG. 6, on the graph line L4, the pulse width converges as the pulse frequency increases. This is close to the graph line of the pulse period (not shown in FIG. 6), which becomes smaller as the pulse frequency becomes higher as the reciprocal of the pulse frequency, and has a high duty (for example, about 80%) at a high pulse frequency. It depends on the setting.

Further, in the example of FIG. 6, at least at a set frequency close to the fundamental frequency of the horn 20 of 400 Hz (basic cycle 2.5 ms) (in the case of the worst case described above), a cycle of 1/3 or less of the fundamental cycle, that is, 0.83 ms It is also an example of setting the pulse width in the following period.

FIG. 7 is a graph showing a schematic example of a circuit waveform in a part of the experimental examples of FIG. In each graph, the gate voltage V (G1) and the drain current I (D1) (corresponding to the horn current) of the duty-driven switch element SE1 (N-type FET) are shown from the upper stage side.

Each graph of FIG. 7 is a graph when the power supply voltage of the battery B is 13.5 V. The graph GR1 has an applied frequency of about 200 Hz, the graph GR2 has an applied frequency of about 600 Hz, and the graph GR3 has an applied frequency of about 1200 Hz. GR4 shows each circuit waveform at an applied frequency of about 2000 Hz. In each graph, the horizontal axis and the vertical axis are common to the scale. Each graph shows the waveform for a certain period of time after the duty drive of the switch element SE1 is started according to the flowchart of FIG. 5, and the duty drive is appropriately performed according to the behavior of the horn current (drain current I (D1)). You can see the situation.

As described above, according to one embodiment of the present invention, only a single horn 20 is used to make the horn 20 sound in a normal manner accompanied by a collision of the movable shaft 23 in the first embodiment, and the second embodiment. In the embodiment, the horn 20 is not accompanied by the collision, and the contact 22 is always closed so that the horn 20 can be sounded with a soft tone different from that of the first embodiment. Further supplementary matters will be described below.

(Regarding changing the sound pressure in the second embodiment)
As described with reference to the examples of FIGS. 6 and 7, in the second embodiment, the pulse frequency in a wide range of 200 Hz to 2000 Hz is maintained while maintaining substantially the same sound pressure (around 80 dB as shown in FIG. 6). You can make the horn 20 sound with.

The drive unit 2 can also be controlled so as to adjust the sound pressure by changing the current, that is, the pulse width at a common pulse frequency. For example, if it is desired to reduce the sound pressure at a certain pulse frequency, the pulse width may be set smaller at this pulse frequency, and if it is desired to increase the sound pressure, the pulse width may be set larger at this pulse frequency. (However, the pulse width may be changed within the range in which the second embodiment is established, that is, within the range in which the contact 22 remains closed.) Here, if the current, that is, the pulse width is increased, Since the current change is also large, the attractive force of the electromagnet by the coil 21 is also strong, and the sound pressure can be increased at the set pulse frequency.

FIG. 8 is a diagram showing a schematic example of changing the pulse width. In FIG. 8, the graph GR10 in which the pulse width is slightly increased (about 20%) with respect to the graph GR1 in FIG. 7 is listed. In the case of the graph GR10, it is possible to increase the sound pressure at the same pulse frequency (about 200 Hz) as the graph GR1. Similarly, when it is desired to reduce the sound pressure at this pulse frequency (about 200 Hz), the pulse width may be made smaller than that in the case of the graph GR1 (not shown).

In one embodiment, for example, in a notification sound when an occupant performs various systematic operations in a motorcycle, a sound in which the sound pressure is changed at a certain frequency (arbitrary frequency that can be set within a certain range) is generated. Depending on the application, the drive unit 2 may set a pulse width (the larger the sound pressure, the longer the pulse width) according to the preset sound pressure.

In another embodiment, the pulse width of a certain frequency (arbitrary frequency that can be set within a certain range) is set to the power supply voltage of the battery B so that the sound pressure becomes constant even if the power supply voltage of the battery B fluctuates. The drive unit 2 may be set so that the pulse width becomes longer as the power supply voltage becomes smaller according to the value of. At this time, the value of the power supply voltage of the battery B may be detected by the voltage detection unit 5, and the drive unit 2 may set the pulse width according to the detected value of the power supply voltage.

That is, as shown in the experimental example of FIG. 6, the higher the voltage of the battery B, the higher the sound pressure tends to be. Therefore, when the power supply voltage of the battery B can fluctuate, this voltage is monitored and the voltage is monitored. By setting the pulse width according to the value as described above, it is possible to keep the sound pressure of the horn 20 constant even if the power supply voltage fluctuates.

10 ... Horn control device, 1 ... Control unit, 2 ... Drive unit, 4 ... Current detection unit, 5 ... Voltage detection unit 20 ... Horn, 21 ... Coil, 22 ... Contact SE1 ... Switch element (N-type FET)
B ... Battery, SW1 ... 1st switch, SW2 ... 2nd switch

Of the present invention
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
When the pulse frequency is set lower than the fundamental frequency of the horn (20) in the threshold value determination, the pulse width for driving is set to 1/3 or less of the fundamental period which is the reciprocal of the fundamental frequency. Cage,
According to the fourth feature, when the pulse frequency is not set lower than the fundamental frequency in the threshold value determination, the pulse width for driving is set to less than 1/4 of the fundamental period. ,
If the pulse frequency is lower than the fundamental frequency, by setting the pulse width for the drive to 1/3 or less of the fundamental period is the reciprocal of the fundamental frequency, within a predetermined control range in said horn (20) Even if there are variations in characteristics, it prevents a resonance state accompanied by collision, and prevents it from reaching a resonance state.
When the pulse frequency is not lower than the fundamental frequency (including the case where it is higher than the fundamental frequency), the pulse width for driving is set to less than 1/4 of the fundamental period which is the reciprocal of the fundamental frequency.
In either case, the pulse width for driving is set to satisfy at least one-third of the basic period, thereby ensuring a certain margin and then the pulse in the voltage pulse train to be applied. The width can be such that the displacement when the movable member (23) vibrates is kept less than the constant distance (DA).

Claims (6)

With the coil (21)
A fixing member (24) arranged in the coil (21) and forming an electromagnet when the coil (21) is energized,
A movable member (23) that is oscillated within a range (DB) until it collides with the fixed member (24) and is displaceable toward the fixed member (24) by the attractive force of the electromagnet.
A contact (22) connected to the coil (21), which is always closed and has a distance (DA) greater than a certain distance (DA) before the movable member (23) collides with the fixing member (24). A mechanical contact (22) that is urged to open when it is displaced significantly,
In the horn control device (10) that controls the drive of the horn (20) by energizing the horn (20) provided with
A control unit (1) for duty-driving the horn (20) to utter by applying a voltage pulse train to the coil (21) is provided.
The pulse width in the applied voltage pulse train is set so that the contact (22) is kept in a closed state by keeping the displacement when the movable member (23) vibrates is less than the fixed distance (DA). A horn control device characterized by being The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
The first aspect of the present invention, wherein at any pulse frequency, the pulse width for driving is set to less than 1/2 of the fundamental period, which is the reciprocal of the fundamental frequency of the horn (20). Horn control device. The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
The first aspect of the present invention, wherein at any pulse frequency, the pulse width for driving is set to 1/3 or less of the fundamental period, which is the reciprocal of the fundamental frequency of the horn (20). Horn control device. The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
When the pulse frequency is set lower than the fundamental frequency of the horn (20) in the threshold value determination, the pulse width for driving is set to 1/3 or less of the fundamental period which is the reciprocal of the fundamental frequency. Cage,
Claim 1 is characterized in that, when the pulse frequency is not set lower than the fundamental frequency in the threshold value determination, the pulse width for driving is set to less than 1/4 of the fundamental period. The horn control device described. A claim, wherein the control unit (1) and the horn (20) are connected in parallel to the battery (B) to provide a common power supply voltage by the battery (B). The horn control device according to any one of 1 to 4. A voltage detection unit (5) for detecting the voltage of the battery (B) that provides a power supply voltage for driving the horn (20) is further provided.
The control unit (1) applies a voltage pulse at a pulse frequency selected from a certain range to drive the horn (20) in duty to produce a sound.
Claims 1 to 5, wherein the smaller the voltage detected by the voltage detection unit (5) is, the longer the pulse width for driving is set at any of the pulse frequencies. The horn control device according to any one.

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