Load detection device and gain adjustment method of load detection device

A load detection device configured to detect a load applied to a measurement object, based on a differential signal output from a load cell having a bridge circuit to which a strain gauge is connected, the load detection device comprising:

• an excitation-side differential amplifier circuit configured to amplify an excitation signal to be transmitted to the load cell;
• a measurement-side differential amplifier circuit configured to amplify a first differential signal output from the load cell;
• and
• a control device configured to control the excitation-side differential amplifier circuit and the measurement-side differential amplifier circuit, wherein
• the control device is configured to
• execute a gain adjustment process of adjusting an output gain by selecting an excitation-side gain by the excitation-side differential amplifier circuit and a measurement-side gain by the measurement-side differential amplifier circuit such that a measurement value measured based on a second differential signal output from the measurement-side differential amplifier circuit falls within a predetermined range, the excitation-side gain and the measurement-side gain being selected from among candidate excitation-side gain values set at predetermined intervals as the excitation-side gain and candidate measurement-side gain values set at predetermined intervals as the measurement-side gain, respectively.