SPawner.cs

using UnityEngine;
using System.Collections;

public class SPawner : MonoBehaviour {

	public int ballCount = 0;
	public int ballCountMax = 10;
	public GameObject paddleBall;

	// Use this for initialization
	void Start () {

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

	public void SpawnBall1Wrap()
	{
		StartCoroutine (SpawnBall1 ());
	}

	IEnumerator SpawnBall1()
	{

		while (ballCount < ballCountMax) {
			Instantiate(paddleBall, new Vector3(transform.position.x, transform.position.y, transform.position.z), Quaternion.identity);
			ballCount++;
			yield return new WaitForSeconds(4f);
		}
	}
}