How will i drag my object with out object disturb?

Hi all,

In a table i have an pendulum set. In that table and set of the pendulum is separate object. my task is when ever i am dragging my table the set also come with that table.

I wrote code like this:

  public class DragObject : MonoBehaviour {
  public Camera camera;
  Vector3 initial,next;
  public Transform Table;
 // Use this for initialization
 void Start () {
 camera = GameObject.Find("Main Camera").camera as Camera;
 Table= GameObject.Find("Pendulumset").transform as Transform;
 initial = transform.position;
 }

 // Update is called once per frame
 void Update () {

 }
 void OnMouseDrag() {
 transform.position = camera.ScreenToWorldPoint(new Vector3(Input.mousePosition.x,Input.mousePosition. y,12));
 next = transform.position;
 next = next - initial;
 initial = transform.position;
 Table.transform.position += next;
 }
 }

But the above code is when i am dragging my table that will going but the pendulum set didn't come properly. And i my observation it is also taking click. when i am click the table right side the table mid point comes to that point. table have box collider also.

can any help me on this code. i want only x axis moving.