is reduced meanwhile the through hole 111 is sealed by the rolling elements 20 from both sides thus creating a receiving space for storage of lubrication the chain 12 serves to link the respective partitions 11 together thus constituting the retaining device 10 since the contact area between the rolling elements 20 and the partitions 11 are made up of the contact points 112 and the through hole 111 between the neighboring rolling elements 20 can be used to store the lubrication the contact area between the rolling elements 20 and the partitions 11 will not be increased too much even if the contacting points 112 are worn out at least in the area of the through hole 111 no friction will be caused between the rolling elements 20 and the partitions 11 moreover the through hole 111 is filled with lubrication for providing good lubricating effect for the rolling elements 20 and the partitions 11 fig3 shows the retaining device for rolling element in accordance with the present invention is changing the moving direction the rolling elements 20 and the partitions 11 are moving in a return path 60 to change the moving direction at this moment the chain 12 of the retaining device 10 is curved for enabling the rolling elements 20 and the partitions 11 to change their moving direction meanwhile.