Hydraulic control device for belt stepless speed change gear

Abstract

Abstract PURPOSE:To avoid an unnecessary power loss of a hydraulic pump for increase in pressure by providing a relief valve between the second line oil path and the first line oil path, thereby to discharge working fluid to the first line oil path by an increase in the second line oil pressure. CONSTITUTION:When the moving stroke of a movable rotor 22 amounts to the maximum, differential pressure between the second line oil path 46 and an oil path 52 is extinguished. As a pressure-regulating valve 50 throttles a circulating sectional area, the second line oil pressure is suddenly about to increase. The pressure in the second line oil path 46 is increased to cause a relief function of the pressure regulating valve 50, so that working fluid in the second line oil path 46 is circulated to the first line oil path. Thus, increase in pressure in the second line oil path is checked to avoid unnecessary power loss.

Inventors

• 👤 Daisaku Sawada
• 👤 沢田　大作
• 👤 Masami Sugaya
• 👤 正美 菅谷
• 👤 Ryuji Imai
• 👤 竜二 今井
• 👤 Yoshinobu Soga
• 👤 吉伸 曽我

Bibliographic Details