diff --git a/protos/stationLayoutGraphics.proto b/protos/stationLayoutGraphics.proto
index d269bd9..f0a890f 100644
--- a/protos/stationLayoutGraphics.proto
+++ b/protos/stationLayoutGraphics.proto
@@ -162,6 +162,13 @@ message AxleCounting {
 // }
 
 message Turnout { //(后端不关注)
+
+  enum SwitchMachineType {
+    Unknown = 0;
+    ZDJ9_Single = 1;
+    ZDJ9_Double = 2;
+  }
+
   CommonInfo common = 1;
   string code = 2;
   repeated Point pointA = 6; // A端坐标列表
@@ -176,6 +183,7 @@ message Turnout { //(后端不关注)
   string paTrackSectionId = 15;                  // A端轨道区段id
   string pbTrackSectionId = 16;                  // B端轨道区段id
   string pcTrackSectionId = 17;                  // C端轨道区段id
+  SwitchMachineType switchMachineType = 18;      // 转辙机类型
 }
 
 /** 左右行 **/