Abstract: A smart drug injection device is disclosed, comprising a main body, a circuit board, a display, a syringe and a transmission mechanism; the main body comprises an accommodating space and a power button; the circuit board comprises a control unit and a storage unit; the transmission mechanism comprises a motor, a screw rod, a propelling block and a movable clamp, with the control unit electrically connected to the storage unit, the power button, the motor and the display, the motor connected to the screw rod, the propelling block movably arranged on the screw rod, the movable clamp disposed at one end of the propelling block and movable between two positions; the syringe is on one side of the main body and comprises a cylinder and a needle holder, one end of the cylinder has a needle and the other end is assembled with the needle holder.

Abstract: A smart drug injection device is disclosed, comprising a main body, a circuit board, a display, a syringe and a transmission mechanism; the main body comprises an accommodating space and a power button; the circuit board comprises a control unit and a storage unit; the transmission mechanism comprises a motor, a screw rod, a propelling block and a movable clamp, with the control unit electrically connected to the storage unit, the power button, the motor and the display, the motor connected to the screw rod, the propelling block movably arranged on the screw rod, the movable clamp disposed at one end of the propelling block and movable between two positions; the syringe is on one side of the main body and comprises a cylinder and a needle holder, one end of the cylinder has a needle and the other end is assembled with the needle holder.

Abstract: A control device includes both a heating element and a temperature sensor. The control device has the form of a Wheatstone bridge which applies sensing current to the heating element. When the bridge is unbalanced, the control device may apply heating current to the heating element. In one embodiment, the sensing current is switched, so that it flows only for a relatively small part of the electrical cycle. The circuit also includes a provision for reduction or elimination of electrical spikes. The circuit further includes a calibration arrangement, which enables the user to adjust the bridge without passing heating current through the heating element. Another feature of the invention enables the set point of the bridge to be remotely controlled, by adjusting a level of analog current applied to the bridge. The circuit also includes an arrangement for compensating for temperature-induced changes in its components.