Infusion pump

An infusion pump for administering controlled doses of a fluid, the pump comprising:na receptacle for storing the fluid, the receptacle having an outlet for dispensing the fluid;a plunger;a propulsion mechanism which urges the plunger in a direction to pressurise the fluid and dispense it through the outlet; anda retaining member which acts on the plunger to control or prevent travel of the plunger;the retaining member operably connected to a motor via a worm and worm-wheel drive, in an arrangement wherein rotation of the worm causes the worm-wheel drive to rotate, thereby to control said travel of the plunger to dispense the fluid.

An infusion pump for administering controlled doses of a fluid, the pump comprising:na receptacle for storing the fluid, the receptacle having an outlet for dispensing the fluid;a plunger;a propulsion mechanism which urges the plunger in a direction to pressurize the fluid and dispense it through the outlet;a retaining member which acts on the plunger to control or prevent travel of the plunger, the retaining member operably connected to a stepper motor via a worm and worm-wheel drive; anda brake mechanism for inhibiting uncontrolled movement of the plunger, wherein the brake mechanism comprises a cruciform spring for engaging with a wall of the receptacle.

An infusion pump for administering controlled doses of a fluid, the pump comprising:na receptacle for storing the fluid, the receptacle having an outlet for dispensing the fluid;a plunger;a propulsion mechanism which urges the plunger in a direction to pressurize the fluid and dispense it through the outlet;a retaining member which acts on the plunger to control or prevent travel of the plunger, the retaining member operably connected to a stepper motor via a worm and worm-wheel drive; anda brake mechanism for inhibiting uncontrolled movement of the plunger, wherein the brake mechanism comprises a brake member for engaging with a wall of the receptacle, wherein during normal operation of the pump, the brake member adopts a retracted position and does not engage a wall of the receptacle, and if the retaining member breaks, the brake member adopts a rest position and engages a wall of the receptacle.

An infusion pump for administering controlled doses of a fluid, the pump comprising:na receptacle for storing the fluid, the receptacle having an outlet for dispensing the fluid;a plunger;a propulsion mechanism which urges the plunger in a direction to pressurize the fluid and dispense it through the outlet;a retaining member which acts on the plunger to control or prevent travel of the plunger, the retaining member operably connected to a stepper motor via a worm and worm-wheel drive; and

An infusion pump for administering controlled doses of a fluid, the pump comprising:na receptacle for storing the fluid, the receptacle having an outlet for dispensing the fluid;a plunger;a propulsion mechanism which urges the plunger in a direction to pressurize the fluid and dispense it through the outlet;a retaining member which acts on the plunger to control or prevent travel of the plunger, the retaining member operably connected to a stepper motor via a worm and worm-wheel drive; anda brake mechanism for inhibiting uncontrolled movement of the plunger, wherein the brake mechanism comprises a brake member for engaging with a wall of the receptacle, and wherein the brake member is arranged to cause the plunger to tilt if the retaining member fails, thereby causing jamming between the plunger and a wall of the receptacle.