The present application is based on and claims the benefit of priority of Japanese Patent Application No. 2020-203693, filed on Dec. 8, 2020, the disclosure of which is incorporated herein by reference.
The present disclosures generally relates to variable resistors and electronic devices.
A conventional potentiometer has (i) a resistor body extending in a spiral shape from one end, i.e., a start end, to the other end, i.e., a terminal end, (ii) a start terminal attached to the start end of the resistor body, (iii) an end terminal attached to the terminal end of the resistor body, and (iv) an inner peripheral wiper and an outer peripheral wiper respectively sliding on the resistor body.
It is an object of the present disclosure to provide a variable resistor and an electronic device in which an increase in the number of components is suppressed.
Objects, features, and advantages of the present disclosure will become more apparent from the following detailed description made with reference to the accompanying drawings, in which:
Hereinafter, a plurality of embodiments for carrying out the present disclosure will be described with reference to the drawings. In each of the embodiments, parts corresponding to the elements described in the preceding embodiment(s) are denoted by the same reference numerals, and redundant explanation may be omitted. When only a part of a configuration is described in an embodiment, an un-described part of the configuration is supplemented by, i.e., with reference to, the preceding embodiment.
In addition, not only the combination of the parts that explicitly indicate as combinable in each of the embodiments, but also the combination of the embodiments, of the embodiment and the modification(s), and of the modifications is possible unless otherwise described as problematic.
In the following, an example where an electronic device 700 controls each of motor devices provided in a vehicle air conditioner 1000 will be described. However, the motor device controlled by the electronic device 700 is not limited to the devices provided in the vehicle air conditioner 1000. Other motor devices mounted on the vehicle may also be controlled by the electronic device 700. The electronic device 700 may control a motor device for adjusting an opening degree of a valve device such as a three-way valve that switches a flow of a liquid such as engine cooling water. Alternatively, a motor device mounted on a vehicle other than a vehicle may also be controlled by the electronic device 700.
In
The vehicle air conditioner 1000 includes an air-conditioning case 100 in which an air path through which airflows is formed. The air-conditioning case 100 houses various devices used for air-conditioning operation in its inside. The air-conditioning case 100 is formed with two air intake ports, i.e., an inside air intake 110 and an outside air intake 120. The air-conditioning case 100 is formed with a defroster outlet 130 that blows air-conditioning air to a front window of the vehicle. The air-conditioning case 100 is formed with a face outlet 140 that blows air-conditioning air above front seats. The air-conditioning case 100 is formed with a foot outlet 150 that blows air-conditioning air at a lower part of the front seats.
The vehicle air conditioner 1000 includes a blower 310, an evaporator 320, and a heater core 330. The blower 310 is a device for flowing/blowing air into the air-conditioning case 100. The evaporator 320 is a heat exchanger, in an inside of which a refrigerant flows, for cooling the air by removing heat of vaporization from the surrounding air when the refrigerant vaporizes from a liquid to a gas. The heater core 330 is a heat exchanger in which high-temperature engine cooling water flows inside and heats the surrounding air using heat of the engine cooling water. However, instead of the heater core 330, an electric heater or the like that consumes electric power to heat the air may be used, or both of the heater core 330 and the electric heater may be used in combination.
The vehicle air conditioner 1000 includes an inside/outside air switching door 210 for opening/closing the inside air intake 110 and the outside air intake 120. The inside/outside air switching door 210 is a door device that adjusts an amount of air introduced into the air-conditioning case 100 from the inside air intake 110 and the outside air intake 120. The door device is also called as a flap device. The door device is also called as a damper device.
The inside/outside air switching door 210 realizes an inside air mode in which the air-conditioning air is circulated in the vehicle by opening the inside air intake 110 and closing the outside air intake 120. The inside/outside air switching door 210 realizes an outside air mode in which the air-conditioning air is taken in from the outside of the vehicle by closing the inside air intake 110 and opening the outside air intake 120. However, in the outside air mode, the inside air intake 110 does not have to be completely closed. For example, by slightly opening the inside air intake 110, the inside air may be taken in at a smaller rate than the outside air for circulating the air.
The vehicle air conditioner 1000 includes an air mix door 230 for adjusting the temperature of the air-conditioning air. The air mix door 230 is provided downstream of the evaporator 320 and upstream of the heater core 330 in the air flow inside the air-conditioning case 100. By controlling the opening degree of the air mix door 230, the amount of air that passes through the heater core 330 and is heated can be adjusted.
The vehicle air conditioner 1000 includes a defroster door 250 for opening and closing the defroster outlet 130. The defroster door 250 is a door device that adjusts the presence or absence of air-conditioning air blown from the defroster outlet 130 and the amount of blown air therefrom. The vehicle air conditioner 1000 includes a face door 260 for opening and closing the face outlet 140. The face door 260 is a door device that adjusts the presence or absence of air-conditioning air blown out from the face outlet 140 and the amount of blown air therefrom. The vehicle air conditioner 1000 includes a foot door 270 for opening and closing the foot outlet 150. The foot door 270 is a door device that adjusts the presence/absence and the amount of air-conditioning air blown out from the foot outlet 150.
The vehicle air conditioner 1000 includes five outlet modes: defroster mode, face mode, foot mode, bi-level (B/L) mode, and foot defroster (F/D) mode. However, the types of outlet modes are not limited to the above-described five modes. The defroster door 250, the face door 260, and the foot door 270 are door devices for switching modes in the vehicle air conditioner 1000, and are also called mode doors. In the drawings, the defroster mode is shown as “DEF”, the face mode is shown as “FACE”, the foot mode is shown as “FOOT”, the bi-level mode is shown as “B/L”, and the foot defroster mode is shown as “F/D”.
The inside/outside air switching door 210 can rotate in a range from a state where the inside air intake 110 is closed to a state where the outside air intake 120 is closed. A rotatable angle of the inside/outside air switching door 210 is, for example, 100°. The air mix door 230 can rotate in a range from a state in which the amount of air passing through the heater core 330 is minimized to a state in which the amount of air not passing through the heater core 330 is minimized. The rotatable angle of the air mix door 230 is, for example, 180°.
The defroster door 250 can rotate in a range from a state in which the defroster outlet 130 is closed to a state in which the defroster outlet 130 is completely open. A rotatable angle of the defroster door 250 is, for example, 90°. The face door 260 can rotate in a range from a state in which the face outlet 140 is closed to a state in which the face outlet 140 is completely open. A rotatable angle of the face door 260 is, for example, 90°. The foot door 270 can rotate in a range from a state in which the foot outlet 150 is closed to a state in which the foot outlet 150 is completely open. A rotatable angle of the foot door 270 is, for example, 90°.
Three mode doors including the defroster door 250, the face door 260 and the foot door 270 may be configured as one continuous door device. For example, a rotary door that opens and closes each of the outlets by rotating a door plate portion formed in an arcuate face shape may be adopted as the continuous door device. In such case, one door plate portion has functions as three door devices of the defroster door 250, the face door 260, and the foot door 270. A rotatable angle of the rotary door is, for example, 300°.
The inside/outside air switching door 210, the air mix door 230, the defroster door 250, the face door 260, and the foot door 270 are door devices in which an angle of the door plate portion is adjusted by a servomotor. Since the flow rate of air in the door plate portion changes depending on the angle of the door plate portion, it is preferable to control the position of the angle of the door plate portion of each door device with as high accuracy as possible.
In
The DC motor 510 includes a stator having a permanent magnet that functions as a field magnetic pole. The DC motor 510 has an air gap on an inner circumference of the field magnetic pole and includes a rotor. The DC motor 510 includes a commutator on the same axis as the rotor. The commutator is also called a commutator. The DC motor 510 includes a brush for contacting the commutator and passing a current through the commutator. The DC motor 510 is configured such that the commutator in contact with the brush is constantly switched by being rotationally driven.
The speed reduction unit 520 is a portion that decelerates the rotation of the DC motor 510 and transmits the rotation to the rotating part 690. The speed reduction unit 520 can adjust the torque and rotation number required for the actuator 500. The speed reduction gear 520 includes a plurality of gears including a worm gear.
The rotating part 690 is a portion of the actuator 500 that outputs a driving force to the outside. The rotating part 690 is connected to the door device of the vehicle air conditioner 1000 via a link (not shown) or the like. The door device rotates with the rotation of the rotating part 690. Each of the outlets can be opened and closed as the rotating part 690 rotates.
The variable resistor 600 is a device that detects the amount of rotation of the rotating part 690. The resistance value acquired by the variable resistor 600 changes according to the amount of rotation of the rotating part 690. A predetermined voltage is applied to the variable resistor 600. The variable resistor 600 can detect a voltage corresponding to the resistance value. The configuration of the variable resistor 600 will be described in details below.
<Configuration of Variable Resistor>
The mechanical configuration of the variable resistor 600 will be described. Three directions orthogonal to one another are referred to as an X direction, a Y direction, and a Z direction. The Z direction corresponds to one direction, and is also known as a vertical direction.
As shown in
In the drawings, the first conductive pattern 611, the second conductive pattern 621, the electrode 660, and the resistor body pattern 650 are respectively shown as hatched in the top view, for the ease of distinction from each other.
Further, in order to show which position of the main body 670 the cross-sectional line shown in
The substrate 640 has a flat shape having a thin thickness in the Z direction, which is made of, for example, glass epoxy. As shown in
The first conductive pattern 611, the second conductive pattern 621, the resistor body pattern 650, and the electrode 660 are respectively screen-printed on the first main surface 640a. The third conductive pattern 631 is screen-printed on each of the second main surface 640b, the partition wall surface 640c, and the connecting surface 640d.
The first conductive pattern 611, the second conductive pattern 621, and the third conductive pattern 631 are respectively a coating in which silver powder is dispersed in a binder such as phenol resin. Note that the first conductive pattern 611, the second conductive pattern 621, and the third conductive pattern 631 are not limited to the coating in which silver powder is dispersed in a binder such as phenol resin. The print patterns of the first conductive pattern 611, the second conductive pattern 621, and the third conductive pattern 631 will be described later.
The first conductive terminal 612, the second conductive terminal 622, and the third conductive terminal 632 are conductive members made of a metal material. The first conductive terminal 612 is electrically and mechanically connected to the first conductive pattern 611. The second conductive terminal 622 is electrically and mechanically connected to the second conductive pattern 621. The third conductive terminal 632 is electrically and mechanically connected to the third conductive pattern 631.
The resistor body pattern 650 is a coating in which carbon powder is dispersed in a binder such as phenol resin. Note that the resistor body pattern 650 is not limited to a coating in which carbon powder is dispersed in a binder such as phenol resin. The print pattern of the resistor body pattern 650 will be described later.
The electrode 660 is a coating in which silver powder is dispersed in a binder such as phenol resin. Note that the electrode 660 is not limited to a coating in which silver powder is dispersed in a binder such as phenol resin. The print pattern of the electrode 660 will be described later.
The case 675 is formed of an insulating resin member or the like. As shown in
The case 675 has a first wall portion 671 and a third wall portion 673 arranged apart from each other in the X direction in the substantially rectangular parallelepiped body. The case 675 has a second wall portion 672 that connects the first wall portion 671 and the third wall portion 673 in the substantially rectangular parallelepiped body. The case 675 has a fourth wall portion 674 that connects the first wall portion 671 and the third wall portion 673 on a substantially cylindrical body side.
Further, the substrate 640 is inserted into the case 675 so that the first main surface 640a is exposed therefrom. Similar to the case 675, the substrate 640 also has a shape which is made up as a combination of a substantially rectangular parallelepiped body having a thin thickness in the Z direction and a substantially cylindrical body arranged in the Y direction. The above-mentioned through hole 641 and the case hole 676 communicate with each other in the Z direction to form a communication hole 681.
The rotating part 690 includes: an opposing part 691 opposing or facing the case 675; a shaft portion 692 extending in the Z direction from an opposing surface 691a located on a case 675 side of the opposing part 691; and a slider 695 provided on the opposing surface 691a of the opposing part 691. As shown in
Further, the opposing part 691 is provided with a recess 693 recessed toward the opposing surface 691a on a back surface 691b on the back side of the opposing surface 691a. The recess 693 is provided with an operation shaft (not shown). The opposing part 691 can rotate 360° in the circumferential direction in conjunction with the operation shaft. Note that the rotation of the opposing part 691 is not limited to the rotation by the operation shaft. The opposing part 691 may be directly connected to the speed reduction unit 520 to rotate in the circumferential direction in conjunction with the speed reduction unit 520. The speed reduction unit 520 may be provided on the operation shaft.
As described above, the slider 695 is provided on the opposing surface 691a of the opposing part 691. The slider 695 has a first sliding portion 696 and a second sliding portion 697 respectively extending from the opposing surface 691a toward the first main surface 640a. Note that
As shown in
<Print Pattern of Conductive Pattern>
As described above, the first conductive pattern 611 and the second conductive pattern 621 are printed on the first main surface 640a of the substrate 640.
As shown in
As shown in
As shown in
As shown in
<Extension and Conductive Terminals>
The first extension portion 613, the fourth extension portion 633, and the third extension portion 623 are arranged to be separated from (and substantially in parallel with) each other in the x direction from the third wall portion 673 toward the first wall portion 671. The first conductive terminal 612 is connected to the first extension portion 613. The third conductive terminal 632 is connected to the fourth extension portion 633. The second conductive terminal 622 is connected to the third extension portion 623.
A predetermined voltage is applied across the first conductive terminal 612 and the second conductive terminal 622. The predetermined voltage is, for example, 5 V. The predetermined voltage does not have to be 5 V.
Further, the first conductive terminal 612 is connected to a reference potential. The first conductive terminal 612 may be not connected to the reference potential. In such a case, the second conductive terminal 622 may be connected to the reference potential.
<Resistor Body Pattern and Electrode Print Pattern>
The resistor body pattern 650 has a first resistor body pattern 651 and a second resistor body pattern 652 connected to the first tip portion 615 and the second tip portion 624, respectively. The first resistor body pattern 651 is printed on the first main surface 640a in such a manner that it contacts one side of each of the first tip portion 615 and the second tip portion 624 in the circumferential direction. The second resistor body pattern 652 is printed on the first main surface 640a in such a manner that it contacts the other side of the first tip portion 615 and the second tip portion 624 in the circumferential direction. Therefore, the first resistor body pattern 651, the first tip portion 615, the second resistor body pattern 652, and the second tip portion 624 constitute the annular portion 680 that extends continuously in the circumferential direction.
The electrode 660 is printed on the first main surface 640a in a manner in which the communication hole 681 is annularly surrounded in the circumferential direction on a communication hole 681 side of the annular portion 680. Further, a connection electrode 661 extending from a portion of the electrode 660 located on a communication hole 681 side toward the communication hole 681 is printed on the first main surface 640a. The sixth extension portion 635 is connected to the connection electrode 661.
In other words, the electrode 660 is printed on the first main surface 640a in a manner in which the through hole 641 is annularly surrounded in the circumferential direction on a through hole 641 side of the annular portion 680. Further, the connection electrode 661 extending from a portion of the electrode 660 located on the through hole 641 side toward the through hole 641 is printed on the first main surface 640a. The sixth extension portion 635 is connected to the connection electrode 661.
<Voltage Detection>
As described above, as the opposing part 691 rotates, the first sliding portion 696 slides on one of the resistor body pattern 650, the first conductive pattern 611, and the second conductive pattern 621. Further, the second sliding portion 697 slides on the electrode 660 as the opposing part 691 rotates.
The slider 695 can rotate 360° in the circumferential direction as the opposing part 691 rotates. Therefore, the first sliding portion 696 can slide 360° in the circumferential direction on one of the resistor body pattern 650, the first conductive pattern 611, and the second conductive pattern 621. In other words, the first sliding portion 696 is slidable 360° in the circumferential direction on the annular portion 680. Similarly, the second sliding portion 697 is slidable 360° in the circumferential direction on the electrode 660.
In such manner, the voltage applied to the portion of the resistor body pattern 650 between the first tip portion 615 and the slider 695 in a range of 360° along the circumferential direction can be output to the outside via the electrode 660 and the third conductive portion 630. Then, the voltage applied to the portion of the resistor body pattern 650 between the first tip portion 615 and the slider 695 in a range of 360° in the circumferential direction can be detected by the third conductive terminal 632.
Note that the annular portion 680 of the ideal variable resistor 600 is formed to have a uniform thickness along the z direction in the circumferential direction of 360°. However, a material of the first conductive pattern 611 and the second conductive pattern 621 and a material of the resistor body pattern 650 are different. Therefore, the thickness of the annular portion 680 along the z direction may be not uniform. Therefore, grease (not shown) is applied to the first tip portion 615 and the second tip portion 624.
Further, as the slider 695 rotates with the rotation of the opposing part 691, the resistance value of the portion of the resistor body pattern 650 between the first tip portion 615 and the slider 695 changes.
For example, as shown in
Further, the slider 695 slides on the second resistor body pattern 652 and the electrode 660 from the second tip portion 624 toward the first tip portion 615, respectively. In such case, the resistance value of the portion of the second resistor body pattern 652 between the first tip portion 615 and the slider 695 becomes smaller.
Note that when the first sliding portion 696 of the slider 695 is in contact with the first tip portion 615 and the second sliding portion 697 of the slider 695 is in contact with the electrode 660, the voltage output from the third conductive terminal 632 is 0 V. When the first sliding portion 696 of the slider 695 is in contact with the second tip portion 624 and the second sliding portion 697 of the slider 695 is in contact with the electrode 660, the voltage output from the third conductive terminal 632 is 5 V.
Further, the value of the voltage applied to the portion of the first resistor body pattern 651 between the first tip portion 615 and the slider 695 and the value of the voltage applied to the portion of the second resistor body pattern 652 between the second tip portion 624 and the slider 695 becomes the same at a position in the circumferential direction of 360°.
Therefore, by measuring the voltage output from the third conductive terminal 632, how much in the circumferential direction the slider 695 has rotated from the first tip portion 615 toward the first resistor body pattern 651 side or the second resistor body pattern 652 side is detectable. That is by measuring the voltage of the portion of the annular portion 680 between the first tip portion 615 and the slider 695, it is possible to detect how much the slider 695 is rotated in the circumferential direction from the first tip portion 615.
Whether the slider 695 is located on the first resistor body pattern 651 side or the second resistor body pattern 652 side is electrically determined by the above-mentioned electronic device 700. The electronic device 700 can identify and detect which of the first resistor body pattern 651 side and the second resistor body pattern 652 side the slider 695 is rotated in the circumferential direction.
<Electronic Device>
The electronic device 700 includes a rotation instruction part 710, a rotation direction memory part 720, a time counter 730, a voltage detection part 740, a voltage memory part 750, a voltage change detection part 760, and a position determination part 770. In the drawing, the rotation instruction part 710 is referred to as “RIP”, the rotation direction memory part 720 is referred to as “RDMP”, the time counter 730 is referred to as “TC”, the voltage detection part 740 is referred to as “VDP”, the voltage memory part 750 is referred to as “VMP”, and the voltage change detection part 760 is referred to as “VCDP”, and the position determination part 770 is referred to as “PDP”.
The rotation instruction part 710 plays a role of rotationally driving the DC motor 510 in response to an operation from an operator. In response to the above operation, the rotation instruction part 710 instructs the DC motor 510 to be rotationally driven. Along with such instruction, the rotating part 690 rotates in the circumferential direction to either the first resistor body pattern 651 side or the second resistor body pattern 652 side.
The rotation direction memory part 720 plays a role of storing a rotation direction of the rotating part 690 in the circumferential direction that rotates in response to the instruction of the rotation instruction part 710.
The time counter 730 is a device that counts a predetermined time as one cycle. The predetermined time is, for example, 20 ms. The predetermined time is not limited to 20 ms. The time counter 730 starts the first count at startup. The startup time is a start time of rotation. The time counter 730 may start the first count after a predetermined time from the startup. In such case, the voltage memory part 750 may store a voltage at the start of rotation before the first count.
The voltage detection part 740 plays a role of detecting the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615. For each count of the time counter 730, the voltage of the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is detected by the voltage detection part 740.
The voltage memory part 750 plays a role of storing the voltage detected by the voltage detection part 740. For each count of the time counter 730, the value of the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is stored in the voltage memory part 750.
Note that the value of the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 at the latest count does not have to be stored in the voltage memory part 750. The value of the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 at the latest count may be output to the voltage detection part 740.
The voltage change detection part 760 has a role of comparing the voltage value stored in the voltage memory part 750 with the voltage value detected at the latest count and detecting the amount of change.
The output result of the rotation direction memory part 720 and the output result of the voltage change detection part 760 are taken into the position determination part 770. The position determination part 770 can identify which of the first resistor body pattern 651 side and the second resistor body pattern 652 side the slider 695 is rotated, and can detect how much the slider 695 has rotated in the circumferential direction.
<How to Use the Electronic Device in Vehicle Air Conditioners>
The case where the electronic device 700 is used for or in the vehicle air conditioner 1000 will be described below.
As described above, the rotating part 690 is connected to the door device of the vehicle air conditioner 1000 via a link (not shown) or the like. Therefore, when the rotating part 690 rotates, the outlet mode can be switched to any of defroster mode, face mode, foot mode, bi-level (B/L) mode, and foot defroster (F/D) mode.
Along with such switching, the variable resistor 600 outputs a voltage corresponding to each of the defroster mode, face mode, foot mode, bi-level (B/L) mode, and foot defroster (F/D) mode. V1 is output in the defroster mode and the face mode. V2 is output in the bi-level (B/L) mode and the foot defroster (F/D) mode. In foot mode, Vz is output.
At such timing, as shown in
When the electronic device 700 is activated in response to an operation from the operator, the time counter 730 starts counting, and the voltage detection part 740 detects the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615. Then, the voltage at the start of rotation is stored by the voltage memory part 750.
As shown in
In order to solve such a problem, the rotation instruction part 710 first rotates the rotating part 690 to either the first resistor body pattern 651 side or the second resistor body pattern 652 side in the circumferential direction. For example, if the rotating part 690 rotates clockwise, the rotation direction is stored by the rotation direction memory part 720. Then, the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is detected after a predetermined time by the voltage detection part 740. Further, the voltage change detection part 760 compares the voltage value at the start of rotation with the voltage value after a predetermined time, and the amount of change is detected.
As shown in
Therefore, the position determination part 770 can identify that the position of the slider 695 at the start of rotation is in the face mode position. When a target outlet mode is set to the foot defroster (F/D) mode at a start time of the electronic device 700, the slider 695 is kept rotated clockwise (i) from a rotated position by an amount of predetermined time from the face mode position (ii) to(ward) the foot defroster (F/D) mode position. Then, at a timing of when the slider 695 reaches the position of the foot defroster (F/D) mode, the rotation of the opposing part 691 is stopped.
<Operation and Effects>
As described above, the third conductive pattern 631 has the fourth extension portion 633, the fifth extension portion 634, and the sixth extension portion 635. The fourth extension portion 633 extends on the connecting surface 640d from the first main surface 640a toward the second main surface 640b. The fifth extension portion 634 extends on the second main surface 640b from a tip of the fourth extension portion 633 toward the through hole 641. The sixth extension portion 635 extends on the partition wall surface 640c from the tip of the fifth extension portion 634 toward the first main surface 640a. The sixth extension portion 635 is connected to the connection electrode 661.
According to such configuration, it is not necessary to provide a gap for passing the third conductive pattern 631 at a position between the first tip portion 615 and the second tip portion 624 in the circumferential direction. As a result, the annular portion 680 extending continuously in the circumferential direction can be formed on the first main surface 640a.
Therefore, the first sliding portion 696 of the slider 695 is always slid on the annular portion 680 at the same radial position regardless of the rotation position of the opposing part 691. Regardless of the rotation position of the opposing part 691, a voltage corresponding to the resistance value of the portion of the resistor body pattern 650 between the first tip portion 615 and the slider 695 is detected at the third conductive terminal 632.
Thus, there is no need to provide a plurality of sliders 695 on the opposing part 691. Further, the number of components of the variable resistor 600 is reducible.
As described above, the electronic device 700 includes a rotation instruction part 710, a rotation direction memory part 720, a time counter 730, a voltage detection part 740, a voltage memory part 750, a voltage change detection part 760, and a position determination part 770.
The rotation instruction part 710 instructs the DC motor 510 to be rotationally driven. The rotation direction memory part 720 stores the rotation direction of the rotating part 690 in the circumferential direction. The time counter 730 counts a predetermined time as one cycle. For each count of the time counter 730, the voltage of the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is detected by the voltage detection part 740. For each count of the time counter 730, the value of the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is stored in the voltage memory part 750.
The value of the voltage detected at the start of rotation by the voltage change detection part 760 is compared with the value of the voltage detected at the latest count. The amount of change is detected by the voltage change detection part 760. The output result of the voltage change detection part 760 and the output result of the rotation direction memory part 720 are taken into the position determination part 770. Therefore, the position determination part 770 can identify how much the slider 695 has rotated in the circumferential direction to either the first resistor body pattern 651 side or the second resistor body pattern 652 side.
In the present embodiment, the first resistor body pattern 651 is connected to one end in the circumferential direction of the first tip portion 615 and one end in the circumferential direction of the second tip portion 624, respectively. The second resistor body pattern 652 is connected to the other end in the circumferential direction of the first tip portion 615 and the other end in the circumferential direction of the second tip portion 624, respectively.
However, as shown in
Further, as shown in
As shown in
For example, when the circumferential separation distance between the first tip portion 615 and the second tip portion 624 is longer on a first resistor body pattern 651 side than on a second resistor body pattern 652 side, the amount of change in the resistance value per unit length is smaller on the first resistor body pattern 651 side. Therefore, the voltage detection accuracy is improvable on a first resistor body pattern 651 side.
As shown in
The substrate 640 is provided with the first conductive pattern 611, the second conductive pattern 621, the third conductive pattern 631, and the resistor body pattern 650. The annular portion 680 is formed by the first tip portion 615, the second tip portion 624, and the resistor body pattern 650. The first extension portion 613 and the second extension portion 614 included in the first conductive pattern 611 are printed at positions farther away from the communication hole 681 than the resistor body pattern 650 in the orthogonal direction orthogonal to the circumferential direction.
The annular portion 680 is located on a communication hole 681 side in the orthogonal direction orthogonal to the circumferential direction than the electrode 660. The first conductive pattern 611 is printed on the substrate 640 to face the electrode 660 provided on the opposing part 691 in the Z direction. In such manner, the physique/volume of the variable resistor 600 in the X direction and the Y direction may be reduced.
Further, the first conductive terminal 612, the second conductive terminal 622, and the third conductive terminal 632 are arranged in this written order from the third wall portion 673 toward the first wall portion 671 so as to be separated from each other in the X direction. The first conductive terminal 612 is connected to the first conductive pattern 611. The second conductive terminal 622 is connected to the second conductive pattern 621. The third conductive terminal 632 is connected to the third conductive pattern 631.
Further, a connection terminal 636 extending from the substrate 640 toward the opposing surface 691a is connected to the third conductive pattern 631. The connection terminal 636 is slidable on the electrode 660 provided on the opposing part 691. In such manner, the voltage applied to the portion of the resistor body pattern 650 between the first tip portion 615 and the slider 695 is output to the outside via the electrode 660, the connection terminal 636, the third conductive pattern 631, and the third conductive terminal 632.
In the present embodiment, the opposing part 691 included in the rotating part 690 can rotate 360° in the circumferential direction in conjunction with the operation shaft. However, for example, the rotation of the opposing part 691 in the circumferential direction may be mechanically restricted at an abutting position where the face outlet 140 is fully closed. For example, the rotation of the opposing part 691 in the circumferential direction may be mechanically restricted by forming a protrusion or the like on the opposing part 691 and abutting it against a component of the variable resistor 600 positioned closed to the protrusion.
Further, the electronic device 700 has a voltage memory part 780, which stores the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 and detected at the position where the rotation of the opposing part 691 in the circumferential direction is mechanically restricted. Note that, in
In such manner, the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is accurately definable at the position where the rotation of the opposing part 691 in the circumferential direction is mechanically restricted. Thus, a position where the face outlet 140 is fully closed is accurately definable in the opposing part 691.
Note that the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 and defined at the position where the face outlet 140 is fully closed is set to a value higher than 0 V. In other words, the voltage detected from the third conductive terminal 632 is set to a value higher than 0 V.
Similarly, the rotation of the opposing part 691 in the circumferential direction may be mechanically restricted at an abutting position where the defroster outlet 130 is fully opened.
In such manner, the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is accurately definable. Thus, the position at which the defroster outlet 130 is fully opened is accurately definable in the opposing part 691.
Note that the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 and defined at the position where the defroster outlet 130 is fully opened is set to a value higher than 0 V. In other words, the voltage detected from the third conductive terminal 632 is set to a value higher than 0 V. Therefore, the movable range of the opposing part 691 in the circumferential direction may be intentionally made smaller than 360°.
As shown in
Further, as shown in
Next, the electrical connection between the variable resistor 600 and the electronic device 700 is described. As shown in
A capacitor 830 for stabilization is inserted between the first conductive portion 801 and the third conductive portion 803. A first resistance portion 810 for stabilization is inserted between the second conductive portion 802 and the third conductive portion 803. A second resistance portion 820 for limiting electric current is inserted between the third conductive terminal 632 and the third control terminal 703. The capacitor 830 connects or bridges the first conductive portion 801 and the third conductive portion 803 at a position on a conductive terminal 632 side of the first resistance portion 810. The first resistance portion 810 connects or bridges the second conductive portion 802 and the third conductive portion 803 at a position on a conductive terminal 632 side of the second resistance portion 820.
Therefore, an electric current flows from the third conductive terminal 632 to the third control terminal 703 through the second resistance portion 820. The voltage between the first conductive terminal 612 and the third conductive terminal 632 can be detected based on the electric current flowing through the third control terminal 703. In other words, the voltage at the portion of the resistor body pattern 650 between the first tip portion 615 and the slider 695 is detectable based on the electric current flowing through the third control terminal 703.
However, when the slider 695 is damaged due to wear or the like, the electric current flowing through the second conductive terminal 622 flows respectively through the first resistance portion 810 and the second resistance portion 820 to the third control terminal 703. Therefore, the voltage of the portion of the resistor body pattern 650 between the first tip portion 615 and the second tip portion 624 is detectable by the third control terminal 703. In other words, 5 V is always detected from the third control terminal 703. As described above, in the open detection configuration, the voltage applied to the portion of the resistor body pattern 650 between the slider 695 and the first tip portion 615 is lower than 5 V. Therefore, when the detected voltage is 5 V, it indicates that the slider 695 is damaged due to wear or the like (i.e., wear of the slider 695 is recognizable in such manner).
As shown in
Further, when the opposing part 691 is configured to be continuously rotatable in the circumferential direction within a predetermined time, an error of the rotation position with respect to an error of the detected voltage is made smaller. Therefore, the rotation position of the slider 695 according to the voltage detected at the third conductive terminal 632 is accurately determinable. Thus, it is possible to accurately grasp the state of the outlet mode.
Number | Date | Country | Kind |
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JP2020-203693 | Dec 2020 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
4069466 | Williams | Jan 1978 | A |
7583177 | Fan | Sep 2009 | B1 |
Number | Date | Country |
---|---|---|
H05-052643 | Aug 1993 | JP |
H08-114410 | May 1996 | JP |
H09-193646 | Jul 1997 | JP |
3535415 | Jun 2004 | JP |
4283159 | Jun 2009 | JP |
6482883 | Mar 2019 | JP |
Number | Date | Country | |
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20220181051 A1 | Jun 2022 | US |