diff --git a/src/utils/html_generator.py b/src/utils/html_generator.py
index df0245d..616f000 100644
--- a/src/utils/html_generator.py
+++ b/src/utils/html_generator.py
@@ -537,6 +537,19 @@ class HTMLGenerator:
         // 统一按场景包围盒调整相机，避免模型错位/尺度不一致导致观感混乱
         fitCameraToScene();
         
+        // 保存各组件原始位置（分模动画合模时复原用）
+        const cavityHomePos = {{
+            x: cavityMesh ? cavityMesh.position.x : 0,
+            y: cavityMesh ? cavityMesh.position.y : 0,
+            z: cavityMesh ? cavityMesh.position.z : 0,
+        }};
+        const coreHomePos = {{
+            x: coreMesh ? coreMesh.position.x : 0,
+            y: coreMesh ? coreMesh.position.y : 0,
+            z: coreMesh ? coreMesh.position.z : 0,
+        }};
+        const partingHomeOpacity = partingMesh ? partingMesh.material.opacity : 0.3;
+        
         // 动画循环
         function animate() {{
             requestAnimationFrame(animate);
@@ -610,7 +623,7 @@ class HTMLGenerator:
         }}
 
         function splitMold() {{
-            if (!cavityMesh && !coreMesh) return;
+            if (!cavityMesh || !coreMesh) return;
             isSplit = !isSplit;
             const btn = document.getElementById('splitBtn');
             btn.textContent = isSplit ? '合模' : '分模拆分';
@@ -618,33 +631,28 @@ class HTMLGenerator:
             const bboxDims = geometryData.bounding_box?.dimensions || [100, 100, 100];
             const dir = getPartingDirection();
 
-            // 根据分模方向确定拆分轴和距离
             let splitDist, axis;
             if (dir === 'Z') {{
-                // Z轴上下开模：拆分距离取 Z 方向高度的 40%
                 splitDist = bboxDims[2] * 0.4;
                 axis = 'z';
             }} else if (dir === 'Y') {{
-                // Y轴前后开模
                 splitDist = bboxDims[1] * 0.4;
                 axis = 'y';
             }} else {{
-                // X轴左右开模
                 splitDist = bboxDims[0] * 0.4;
                 axis = 'x';
             }}
 
-            // 分型面动画目标透明度
-            const partingTargetOpacity = isSplit ? 0 : 0.3;
+            const partingTargetOpacity = isSplit ? 0 : partingHomeOpacity;
 
-            // 记录起始位置
-            const cavityStart = cavityMesh ? cavityMesh.position[axis] : 0;
-            const coreStart = coreMesh ? coreMesh.position[axis] : 0;
+            const cavityStart = cavityMesh.position[axis];
+            const coreStart = coreMesh.position[axis];
+            const cavityHome = cavityHomePos[axis];
+            const coreHome = coreHomePos[axis];
             const partingStartOpacity = partingMesh ? partingMesh.material.opacity : 0.3;
 
-            // 目标位置：型腔正向移动，型芯负向移动
-            const cavityTarget = isSplit ? splitDist : 0;
-            const coreTarget = isSplit ? -splitDist : 0;
+            const cavityTarget = isSplit ? (cavityHome + splitDist) : cavityHome;
+            const coreTarget = isSplit ? (coreHome - splitDist) : coreHome;
 
             const duration = 800; // ms
             const startTime = performance.now();
@@ -665,17 +673,17 @@ class HTMLGenerator:
                 }}
                 if (partingMesh) {{
                     partingMesh.material.opacity = partingStartOpacity + (partingTargetOpacity - partingStartOpacity) * ease;
-                    if (isSplit && t >= 1) partingMesh.visible = false;
-                    else partingMesh.visible = true;
                 }}
 
                 if (t < 1) {{
                     splitAnimId = requestAnimationFrame(animateSplit);
                 }} else {{
                     splitAnimId = null;
+                    if (partingMesh) partingMesh.visible = !isSplit;
                 }}
             }}
 
+            if (partingMesh) partingMesh.visible = true;
             splitAnimId = requestAnimationFrame(animateSplit);
         }}
     </script>