Medical infusion apparatus

Medical infusion apparatus comprising:

• a liquid reservoir;
• a conduit for delivering liquid from the reservoir to a patient;
• a monitor for monitoring the flow rate of said liquid along said conduit, said monitor comprising means external of said conduit for applying a pulse of heat to liquid at a location in the conduit and radiation sensing means outside a periphery of the conduit including an infra-red sensor spaced from said conduit for sensing a change in temperature of liquid at a position downstream of the location, so that the speed of travel of the heat pulse can be determined in response to radiation sensed by the sensor;
• whereby the monitor is non-intrusive to permit removal of the conduit from the monitor;
• the apparatus further comprising a regulator having an adjustable position for regulating the flow of liquid from the reservoir, and a motor which can be energized to adjust said regulator position, the regulator position being stable while the motor is de-energized.

Medical infusion apparatus comprising:

• a liquid reservoir;
• a conduit for delivering liquid from the reservoir to a patient;
• a monitor for monitoring the flow rate of said liquid along said conduit, said monitor comprising means external of said conduit for applying a pulse of heat to liquid at a location in the conduit and radiation sensing means outside a periphery of the conduit including an infra-red sensor spaced from said conduit for sensing a change in temperature of liquid at a position downstream of the location, so that the speed of travel of the heat pulse can be determined in response to radiation sensed by the sensor;
• whereby the monitor is non-intrusive to permit removal of the conduit from the monitor;
• said apparatus further comprising pressurizing means for applying pressure to the reservoir to cause liquid to flow along the conduit, regulating means for regulating the flow in response to said monitor, and a housing, said housing supporting said reservoir, said conduit, said monitor, said pressurizing means and said regulating means.

Medical infusion apparatus comprising:

• a liquid reservoir;
• a conduit for delivering liquid from the reservoir to a patient;
• a flow monitor for monitoring the rate of flow of liquid along the conduit, said monitor comprising means external of said conduit for applying a pulse of heat to liquid at a location in the conduit and radiation sensing means outside a periphery of said conduit including an infrared sensor spaced from said conduit for sensing a change in temperature of liquid at a position downstream of the location so that the speed of travel of the heat pulse can be determined in response to radiation sensed by the sensor;
• and
• support means for supporting said conduit and said flow monitor;
• said conduit comprising a unitary, integrally-formed insertion member having first and second portions, said first portion being adapted for insertion into said reservoir;
• and
• said insertion member being removable from said support means and said sensing means, and being configured such that, when carried by said support means, said second portion of said insertion member is located in a predetermined position with respect to the flow monitor, whereby the flow monitor can monitor the rate of flow of liquid through said second portion.

Medical infusion apparatus comprising:

• a liquid reservoir;
• a conduit for delivering liquid from the reservoir to a patient;
• a flow rate monitor for monitoring the rate of flow of liquid from the reservoir to the patient;
• control means for intermittently operating the flow rate monitor at predetermined intervals, said control means having first and second operational modes, said predetermined intervals being shorter during the first operational mode than during the second operations mode;
• and
• a flow rate regulator for regulating the flow rate;
• said control means having an output for controlling said flow rate regulator, said control means comprising a microprocessor performing processing apparatus in said active mode, and said microprocessor consuming less current in the standby mode than in the active mode, wherein said microprocessor is arranged to be in its active mode during said first operational mode of said control means, and is caused to enter its standby mode when the control means is in its second operational mode, the control means further including means operable during said second operational mode to cause the microprocessor to enter its active mode in response either to a lapsing of a predetermined interval or to detection of a disturbance in the flow of liquid, so that the microprocessor can then determine and if necessary regulate the flow rate,
• further including means for sensing disturbances in the flow of liquid caused by the appearance of air bubbles in order to cause the microprocessor to enter its active mode.