| 摘要 |
<p>Accurate setting of gas and liquid quantities is achieved by selector switches attached to adjustable counters. These have an electronic input proportional to the quantity to be measured and an output loading to a comparator. One comparator is connected to >=1 further selector to st a throttling value. When this is reached, a control device e.g. a valve is used to reduce the total flow. A further circuit is ten used to completely shut off the flow when the full amount has been delivered. The comparator device contains a logic circuit with an input from an electronic counter and one output loading to the input to the comparator while another goes to the flow control device. An output is generated when a certain flow has passed and the flow finally shut off when the counter reaches zero. Used for repetitive automatic metering of discreet quantities of a gas or liquid. The system described gives an automatic throttling of the flow before the final shutt off.</p> |
