Arrangement and method for measuring a delivery volume and a delivery rate of an intermittently operating pump

An arrangement for detecting a delivery volume and/or a delivery flow, with

• a discontinuously operating pump,
• at least one outlet line and one inlet line and
• a passive valve, which is arranged in the outlet line or the inlet line and which has a valve seat and a valve head, the valve being closed in a first position of the valve head and the valve being open in a second position of the valve head
• a sensor, by means of which values can be detected which indicate whether the valve head is in the first or the second position, and
• a computing unit, which is coupled to the sensor and by means of which the volume delivered by the pump and/or the delivery flow of the pump can be calculated on the basis of the detected values of the sensor,
• the pump operating cyclically, a defined fluid volume being delivered by the pump during each cycle, the valve head being in the first position between two cycles and it being possible for it to be detected by means of the computing unit and the sensor how frequently the valve head changes from the first position to the second, and it being possible for the volume delivered by the pump to be calculated on the basis of the number of changes from the first position to the second, and having
• a test device for detecting a delivery malfunction, which is coupled to the pump and sensor and by way of which it is possible to test whether the valve head has changed from the first position to the second position within a defined time interval after the end of the cycle
• wherein
• the computing unit comprises a memory in which an initial volume in a container connected to the inlet line is stored, and
• wherein the computing unit is set up to calculate a remaining volume in the container and to test whether the delivery malfunction is a malfunction of the pump or an empty state of the container.

A method for metering a plant protective, in which the plant protective is delivered by means of a discontinuously and cyclically operating pump and the delivery volume and/or the delivery flow of the pump is detected, in which

• a pump element is driven, with the result that the plant protective is delivered out of a container, the delivered plant protective opening a passive valve, arranged in an outlet line and/or an inlet line, counter to an opening force of the valve, in that a valve head is moved in relation to a valve seat from a first position into a second position, a defined plant protective volume is delivered by the pump during each cycle, wherein the valve head is in the first position, in which the valve is closed, between two cycles, it being detected how frequently the valve head changes from the first position to the second position, and the volume delivered by the pump being calculated on the basis of the number of changes from the first position to the second,
• wherein
• it is tested whether the valve head has changed from the first position to the second position within a defined time interval after the end of a cycle, and a delivery malfunction is detected if the valve head has not changed from the first position to the second position within the time interval after the end of a cycle
• wherein the initial volume of the plant protective in a container is detected, and
• wherein the remaining volume of the plant protective in the container is calculated and it is tested whether the delivery malfunction is a malfunction of the pump or an empty state of the container.