Hydraulic tension device

Abstract

The invention provides a hydraulic tension device which can prevent the vibration and noise during engine starting and maintain a proper racking pressure of the push bar in the common operation even after the pressure oil is filled. In the hydraulic tension device buffered by oil and forcing the push bar by a spring in the high pressure oil section, the high pressure oil section is divided into two inner sleeves slidably accommodated in an accommodating hole of the inner sleeve on the push bar and the high pressure oil section is forced to the direction of a check valve unit by the spring forced by the inner sleeve.

Description

technical field [0001] The present invention relates to a hydraulic tensioner for applying appropriate tension to, for example, a timing belt of a vehicle engine, a timing chain, and the like. Background technique [0002] A hydraulic tensioner with a one-way valve mechanism is widely used on timing belts or timing chains that transmit rotation between the crankshaft and camshaft of an engine for a vehicle to suppress vibration generated during their operation and maintain proper tension. [0003] Such an existing hydraulic tensioner 500 with a one-way valve mechanism, such as Figure 7 As shown, the slack side of the timing chain C stretched between the driving side sprocket S1 rotated by the crankshaft of the engine and the driven side sprockets S2, S2 fixed on the camshaft is attached to the engine main body, and the push rod 520 The push rod 520 protrudes freely from the front of the housing main body 510, and the push rod 520 pushes the back surface near the swing end ...

AI Technical Summary

Problems solved by technology

[0029] According to this existing hydraulic tensioner, in order to optimally adjust the pushing forces T11 and T12 of the push rod during normal operation when pushing in and protruding, the push rod when starting, pushing in and protruding Both the pushing forces T01 and T02 are small, and there is a problem that the tension force applied to the chain is insufficient, resulting in vibration and noise.

[0030] In addition, as a countermeasure against the insufficient tension force of the chain, when the spring pressing force Ts for pushing the push rod is increased, the pushing forces T11 and T12 of the push rod become too large due to the increase of Ts during normal operation. In particular, when the pushing force T12 of the push rod becomes too large, excessive tension is applied to the chain, which increases the risk of sliding contact noise and wear and damage of parts such as chains and sprockets.

Images