Valve timing adjustment device

Abstract

In a valve timing adjustment device, a first arm projection portion that is caught by a terminal hook portion of a spiral spring and urged toward a lock phase side by the spiral spring is installed on a face opposite to the front surface of a plate in a first arm in a case where a rotational phase of a second rotating body with respect to a first rotating body is on a first rotational phase side, and a second arm projection portion that abuts on an outermost peripheral portion of the spiral spring is installed on a face opposite to the front surface of the plate in a second arm in a case where the rotational phase is on the first rotational phase side.

1 . A valve timing adjustment device comprising: a first rotating body that rotates synchronously with a crankshaft; and a second rotating body that rotates synchronously with a camshaft,
 wherein the first rotating body includes a plate having an opening portion around a rotation axis,   the second rotating body includes: a main body portion that is disposed to pass through the opening portion of the plate and is disposed around the rotation axis; and a holder having a first arm and a second arm that each extends to an outer peripheral side from an end portion of a part of the main body portion projecting from a front surface of the plate,   a spiral spring is installed between the front surface of the plate and the first and the second arms, in which the spiral spring is wound around the main body portion, an inner peripheral side end portion of the spiral spring is held by the plate, and a terminal hook portion of the spiral spring is formed by bending an outer peripheral side end portion toward an outer peripheral side,   a first arm projection portion is caught by the terminal hook portion of the spiral spring, is urged toward a lock phase side by the spiral spring and is installed on a face opposite to the front surface of the plate in the first arm in a case where a rotational phase of the second rotating body with respect to the first rotating body is on a first rotational phase side, and   a second arm projection portion abuts on an outermost peripheral portion of the spiral spring and is installed on a face opposite to the front surface of the plate in the second arm in a case where the rotational phase is on the first rotational phase side.   
     
     
         2 . The valve timing adjustment device according to  claim 1 , wherein the second arm projection portion is configured to be separated from an outermost periphery of the spiral spring in a case where the rotational phase is on a second rotational phase side. 
     
     
         3 . The valve timing adjustment device according to  claim 1 , wherein a first plate projection portion that abuts on an outermost peripheral portion of the spiral spring is installed on the front surface of the plate in a case where the rotational phase is on a second rotational phase side. 
     
     
         4 . The valve timing adjustment device according to  claim 1 , wherein a second plate projection portion that abuts on an innermost peripheral portion of the spiral spring is installed on the front surface of the plate. 
     
     
         5 . The valve timing adjustment device according to  claim 4 , wherein the second arm projection portion is located on a side opposite to the second plate projection portion side with reference to the rotation axis in a case where the rotational phase is on the first rotational phase side. 
     
     
         6 . The valve timing adjustment device according to  claim 1 , wherein a second plate projection portion that abuts on an innermost peripheral portion of the spiral spring is installed on the front surface of the plate, and
 a first plate projection portion that abuts on an outermost peripheral portion of the spiral spring is installed on a side opposite to the second plate projection portion side with reference to the rotation axis at the front surface of the plate in a case where the rotational phase is on a second rotational phase side.   
     
     
         7 . The valve timing adjustment device according to  claim 1 , wherein the second arm projection portion is provided with a spring that urges the second arm projection portion toward a side of the rotation axis in a case where the second arm projection portion abuts on an outermost peripheral portion of the spiral spring and is pushed toward an outer peripheral side. 
     
     
         8 . The valve timing adjustment device according to  claim 7 , wherein the spring is an unequal pitch spring. 
     
     
         9 . The valve timing adjustment device according to  claim 3 , wherein the first plate projection portion is provided with a spring that urges the first plate projection portion toward the rotation axis side in a case where the first plate projection portion abuts on an outermost peripheral portion of the spiral spring and is pushed toward an outer peripheral side. 
     
     
         10 . The valve timing adjustment device according to  claim 9 , wherein the spring is an unequal pitch spring. 
     
     
         11 . The valve timing adjustment device according to  claim 1 , wherein an outer peripheral side end portion of the terminal hook portion of the spiral spring is bent toward an outer peripheral side by an angle larger than 90 degrees.