Energy is a key concern in sensor networks as sensor nodes have a limited battery power and can not be replaced. In order to conserve energy efficiently, we proposed a sink movement scheme by traversing the whole network region to gather data from sensors within one or two hops along an Archimedean spiral trajectory. As the trajectory has a constant linear velocity and angular velocity, the sink can be controlled easily. We also optimized it by designing a simple routing protocol which can balance the energy consumption caused by the different distance from the sink trajectory. With the protocol, we can prolong the lifetime and reduce the delay by increasing the velocity of the sink. Simulation results show that our strategy can greatly prolong the network lifetime and balance energy consumption.