Beckman Coulter Inc., which makes medical testing instruments, said Tuesday that Chairman, President and CEO Scott Garrett has resigned.

Garrett will remain as a full-time, non-executive employee of the company through Jan. 15.

The board of directors appointed J. Robert Hurley as interim president and CEO. Hurley has served as the company's senior vice president of human resources and chairman of Beckman Coulter Japan since 2005.

Glenn S. Schafer, lead independent director, was appointed by the board as non-executive chairman.

Garrett has been CEO for the past five years, and said in a statement released by the company that he he felt the company "is positioned to achieve its long term potential."

Neither Garrett nor the company said in the release why he was leaving, however.

In the statement, Shafer said the board "appreciates Scott's contributions to the company's success" and is "confident in and supportive of the company's management team."