Test device for testing distance between centers of two through holes

A test device for testing whether a distance between centers of a first and a second through holes defined in an article meets a specification, the test device comprising:

• a support member;
• a benchmark member set on a first end of the support member to be positioned at the first through hole with a center line of the benchmark member aligning with a center of the first through hole;
• a test member set on a second end of the support member opposite to the first end, wherein a position of the test member on the second end of the support member is adjustable in a first direction relative to the support member to make the test member position at the second through hole with a center line of the test member aligning with a center of the second through hole;
• and
• a first sliding member slidably mounted to the second end of the support member and slidable in a second direction perpendicular to the first direction, the first sliding member defining a receiving slot facing the test member, wherein a first distance between a central line of the benchmark member and a central line of the receiving slot is equal to a specification distance between centers of the first and second through holes, a second distance between each of opposite ends of the receiving slot and the central line of the receiving slot is equal to a half of a width of the test member plus a permissible error;
• wherein if the first sliding member can move to receive the test member entering the receiving slot at the position of the test member where the width is measured, the first article is qualified;
• and wherein if the test member cannot enter the receiving slot in such manner, the second article is unqualified.