Load detection apparatus

Abstract

To provide a load detection apparatus that can change a load detection range, while minimizing a change of a circuit configuration and control.SOLUTION: A load detection apparatus comprises a control unit, a plurality of load detection units that are connected in series to each other and connected to the control unit, and a resistor that is connected in series to terminals of the plurality of load detection units. The load detection units include a plurality of conducting wires that run therein in parallel with each other, and come into contact with each other upon input of load to conduct with each other. When the voltage falls to a predetermined value or less while the plurality of conductive wires conduct with each other, the control unit determines the presence of input of load.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a load detection device.

Background Art

[0002] Patent Document 1 discloses a load detection device including a plurality of load detection sensors each having a switch, a series resistor, and a parallel resistor inside, and detecting which load detection sensor has received a load based on the resistance values of the series resistor and the parallel resistor for each load detection sensor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, when increasing the number of load detection sensors to widen the load detection range, in a device having a resistor for each load detection sensor as in Patent Document 1, it is necessary to change the circuit configuration and control each time the number of sensors is increased.

[0005] The present disclosure has been made in view of the above, and an object thereof is to provide a load detection device capable of changing the load detection range while minimizing changes in the circuit configuration and control.

Means for Solving the Problems

[0006] The load detection device according to the present disclosure includes a control unit, a plurality of load detection units connected in series with each other and connected to the control unit, and a resistor connected in series to the ends of the plurality of load detection units. The load detection unit includes a plurality of conductive wires that run in parallel inside and conduct electricity by contacting each other when a load is input. The control unit determines that there is a load input when the voltage at the time of conduction of the plurality of conductive wires becomes equal to or lower than a predetermined value.

Advantages of the Invention

[0007] According to the present disclosure, by increasing the number of conducting wires according to the number of load detection units, it is possible to change the load detection range while minimizing changes in circuit configuration and control.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0009] The load detection device according to the embodiment of the present disclosure will be described with reference to the drawings. Note that the components in the following embodiments include those that can be replaced and are easy for those skilled in the art, or those that are substantially the same.

[0010] (Load Detection Device) The configuration of the load detection device according to the embodiment will be described with reference to FIGS. 1 to 3. The load detection device according to the embodiment is for detecting a load input from the outside. This load detection device is mounted on a vehicle equipped with, for example, a battery pack (battery). Examples of such vehicles include hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), fuel cell electric vehicles (FCEV), battery electric vehicles (BEV), and the like.

[0011] As shown in FIG. 1, the load detection device 1 includes a control unit 11, a plurality of load detection units 12, and a plurality of conducting wires 13 and 14.

[0012] The control unit 11 is constituted by, for example, an electronic control unit (ECU). This electronic control device has a microcomputer composed of, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. as main components, and executes various programs. The control unit 11 includes a power supply 111, a microcomputer 112, and a resistor 113.

[0013] The control unit 11 determines the presence or absence of a load input based on the voltage when the plurality of conducting wires 13 and 14 running in parallel inside the load detection unit 12 are conducting. That is, when the voltage when the plurality of conducting wires 13 and 14 are conducting is equal to or lower than a predetermined value (a predetermined threshold value), the control unit 11 determines that there is a load input (see FIG. 3). On the other hand, when the voltage when the plurality of conducting wires 13 and 14 are conducting exceeds the predetermined value, the control unit 11 determines that there is no load input.

[0014] The load detection unit 12 is for detecting a load input from the outside. A plurality of load detection units 12 are connected in series with each other. Among the plurality of load detection units 12, the load detection unit 12 on the start end side (upstream side) is connected in series with the control unit 11. Among the plurality of load detection units 12, the load detection unit 12 on the end side (downstream side) is connected in series with the resistor 113. In FIG. 1, an example including three load detection units 12 has been described, but the number of load detection units 12 may be less than three, or may be more than three.

[0015] The load detection unit 12 includes a plurality of conducting wires 13, 14. These conducting wires 13, 14 run parallel inside the plurality of load detection units 12 and connect the plurality of load detection units 12 in series. Also, the conducting wires 13, 14 connect the load detection unit 12 on the start end side and the control unit 11 in series, and connect the load detection unit 12 on the end side and the resistor 113 in series.

[0016] The conducting wires 13, 14 conduct electricity by contacting each other when a load is input, as shown in FIG. 2(b) for example. Also, as shown in FIG. 3 for example, when a load is input and conduction occurs (when there is a load), the voltage of the conducting wires 13, 14 drops compared to when no load is input (when there is no load). In FIG. 3, for convenience of explanation, only one load detection unit 12 is shown.

[0017] (Load Detection Method) The flow of the load detection method executed by the load detection device according to the embodiment will be described with reference to FIG. 4.

[0018] First, the control unit 11 measures the voltages of the conducting wires 13, 14 that run parallel inside the plurality of load detection units 12 (step S1). Subsequently, the control unit 11 determines whether the measured voltage is equal to or less than a predetermined threshold value (predetermined value) (step S2). This threshold value can be appropriately set based on, for example, the range of the load to be detected.

[0019] In step S2, when it is determined that the measured voltage is less than or equal to the threshold value (Yes in step S2), the control unit 11 determines that there is a load input (step S3) and completes this process. On the other hand, in step S2, when it is determined that the measured voltage exceeds the threshold value (No in step S2), the control unit 11 determines that there is no load input (step S4) and completes this process.

[0020] Here, for example, when the size of the vehicle's battery pack increases, it is necessary to increase the number of load detection sensors to cover the load detection range. And accordingly, it is necessary to provide a load detection circuit in the control unit (ECU). However, there are cases where the circuit cannot be expanded due to board size constraints, diverted design, etc.

[0021] Therefore, in the load detection device according to the embodiment, a plurality of load detection units 12 are connected in series as shown in FIG. 1, so as to expand the load detection range while minimizing the load detection circuit of the control unit 11.

[0022] According to the load detection device according to the embodiment described above, by increasing the number of the load detection units 12 and the number of conductors 13, 14 corresponding to the number of the load detection units 12, the load detection range can be changed while minimizing changes in the circuit configuration and control.

[0023] Further effects and modification examples can be easily derived by those skilled in the art. Therefore, a broader aspect of the present invention is not limited to the specific details and representative embodiments expressed and described as above. Accordingly, various changes can be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

[0024] For example, in the above-described load detection device 1, the resistor 113 was provided inside the control unit 11. However, the location where the resistor 113 is provided can be appropriately changed as needed. For example, like the load detection device 1A shown in FIG. 5, a resistor 15 may be provided outside the control unit 11, and the resistor 15 may be connected in series to the end of the load detection unit 12. Even in the load detection device 1A having such a configuration, by increasing the number of conductors 13 and 14 corresponding to the number of the load detection units 12, the load detection range can be changed while minimizing changes in the circuit configuration and control.

Explanation of Signs

[0025] 1, 1A Load detection device 11 Control unit (ECU) 111 Power supply 112 Microcomputer 113 Resistor 12 Load detection unit 13, 14 Conductors 15 Resistor

Claims

Claim 1 a control unit, a plurality of load detection units connected in series with each other and connected to the control unit, a resistor connected in series to the ends of the plurality of load detection units, comprising, the load detection unit includes a plurality of conductive wires that run in parallel inside and conduct electricity by contacting each other when a load is input, when the voltage at the time of conduction of the plurality of conductive wires becomes equal to or less than a predetermined value, the control unit determines that there is a load input, a load detection device.

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