For　multi-hop　data　collection　in　wireless　sensor　network,　a　fundamental　problem　is　to　improve　the　energy　efficiency　with　the　constraint　of　network　connectivity.　The　HCR　protocol　combines　the　gradient　routing　with　dynamic　clustering　to　provide　connected　and　efficient　inter-cluster　topology　with　limited　transmission　range.　However,　it　suffers　from　the　imbalanced　energy　consumption　which　leads　to　the　poor　performance　in　network　lifetime.　In　this　paper,　we　analyze　the　energy　consumption　of　HCR,　and　find　that　there　is　severe　imbalanced　energy　consumption　among　the　nodes　in　gradient　k　=　1,　where　the　nodes　can　transmit　their　data　to　the　sink　directly.　Based　on　this　observation,　we　propose　a　new　protocol　termed　as　HCR-1,　which　uses　the　adaptive　routing　decision　and　the　tunable　cost　function　to　balance　the　energy　consumption　of　cluster　heads.　Simulation　results　show　that　HCR-1　protocol　can　effectively　balance　the　energy　consumption　of　nodes,　and　extend　the　network　lifetime　for　over　30%.