Abstract: A limiting valve (4) is provided in an inhalation therapy unit with a valve member (13) which closes an air through opening (12) in the idle state and corresponding to the pressure difference occurring over the valve opens same substantially proportionally up to a threshold value. If the threshold value is exceeded, the valve member (13) abuts against a limiting member (16) which limits the movement of the valve member (13) and the air passage orifices (17) of which are partially closed by the valve member (13) so that air can only flow through the air passage auxiliary orifices remaining free. In this manner the patient using the inhalation therapy unit is urged to breath in the range below the threshold value, as his respiration above the threshold value is opposed by a considerably higher resistance.

Abstract: The invention relates to a breath simulator, which comprises a pump means (1) and a computer means (3). The computer means (3) controls the pump means (1) in such a manner that a stored breathing pattern of a patient is produced on a connecting piece (12) of the pump means. With the aid of the breath simulator, therapeutical nebulisers can be examined.