LOAD GENERATING DEVICE

To provide a load generating device which achieves reduction of an axial dimension, can be used as a power transmission device capable of switching transmission and interception of power according to the rotation number of a driving side rotary member and an actuator, and does not need an external power source device.SOLUTION: A load generating device includes: an annular cam slide 11 which is fixed to a shaft member 3 serving as a driving side rotary member and rotates integrally with the shaft member 3; an annular piston 9 which is disposed closer to one axial side than the cam slide 11, rotates integrally with the shaft member 3, and is provided at the shaft member 3 so as to be movable in an axial direction; and multiple balls 13 which are disposed between the cam slide 11 and the piston 9 at a predetermined interval in a circumferential direction and contact with the cam slide 11 and the piston 9. The multiple balls 13 move between the cam slide 11 and the piston 9 by centrifugal force generated by the balls 13 rotating with the cam slide 11 and the piston 9 to move the piston 9 to the one axial side and place the piston 9 in contact with a driven side rotary member 5.SELECTED DRAWING: Figure 1 【課題】軸方向寸法を短縮化し、駆動側回転部材の回転数に応じて動力の伝達と遮断とを切り替え可能な動力伝達装置や、アクチュエータとして用いたりすることができ、外部動力源装置を必要としない荷重発生装置を提供すること。【解決手段】 駆動側回転部材である軸部材３に固定され、軸部材３と一体回転する環状のカムスライド１１と、カムスライド１１よりも軸方向一方側に配置され、軸部材３と一体回転するとともに軸方向に移動可能に軸部材３に設けられた環状のピストン９と、カムスライド１１とピストン９との間に周方向所定間隔に介装され、カムスライド１１とピストン９とに接触している複数のボール１３とを有し、複数のボール１３は、カムスライド１１とピストン９とともに回転することによる遠心力によってカムスライド１１とピストン９との間を移動することにより、ピストン９を軸方向一方へ移動させ、従動側回転部材５へ接触させる。【選択図】図１