Displacement detection device

A displacement detection device for detecting displacement of a second member relative to a first member in a predetermined direction, the displacement detection device comprising:

• a first plate member configured to extend in the predetermined direction;
• a second plate member configured to extend in the predetermined direction;
• and
• a sensor configured to detect displacement,
• wherein
• the first plate member protrudes in a first direction orthogonal to the predetermined direction by being bent at least at four places,
• the second plate member protrudes in a second direction opposite to the first direction by being bent at least at four places,
• both end portions of the first plate member and both end portions of the second plate member are connected to each other,
• each of the first plate member and the second plate member includes, as both the end portions, a first end portion attached to the first member and a second end portion attached to the second member, and further includes an intermediate portion interposed between both the end portions,
• a gap is formed between the intermediate portion of the first plate member and the intermediate portion of the second plate member,
• the sensor detects a change in the gap, and
• when the second member is displaced in the predetermined direction, an amount of the change in the gap is larger than an amount of displacement of the second member.