Eaton Corporation

Scott E Yakimow

Wayne B Wenker

Sohan L Uppal

Gary R Kassen

Michael W Barto

Barun Acharya

Rand J Erpelding

An integral brake assembly for a gerotor motor of the type including valving (41) disposed forwardly of the gerotor gear set (15). Orbital and rotational movement of the gerotor star member (31) is transmitted to an output shaft (43) by a main drive shaft (51), which includes a rearwardly extending brake portion (107). The motor includes an endcap assembly (21) defining a brake chamber (73) into which the brake portion (107) extends. A cylindrical brake member (91) is disposed in the brake chamber (73), and includes a circular surface (109) for frictional engagement with a lock piston (75). The brake member (91) also includes a forward generally annular surface (115) for frictional engagement with either the gerotor gear set (15) or an adjacent wear plate (89). The invention at least reduces the need for expensive friction discs in order to achieve a desired level of brake torque, and also utilizes inherent friction in various brake parts for some of the required brake torque.

Low cost compact design integral brake

A fluid pressure motor of the type including a gerotor gear set (15) including a star member (31) which orbits and rotates. The motor includes valving (41) which is disposed forwardly of the gerotor gear set, and an end cap assembly (21;111) disposed rearwardly of the gerotor gear set. The star member (31) defines a central opening (89;127) at the rearward end thereof, which may be defined by a separate insert member (125). Within the end cap assembly (21;111) is a lock piston (75;133) biased by a pair of Belleville washers (85,87;121) toward an engaged position (FIG. 1; FIG. 4) in which a lock portion (79) has its beveled portion (91;135) in engagement with the central opening (89;127) of the star (31), thus preventing any further orbital motion of the star, and serving as a parking lock. The lock piston (75;133) and end cap assembly (21;111) define a pressure chamber (99;119) which may be pressurized by an external signal (95) to move the lock piston to its disengaged position (FIG. 2) in which the beveled portion (91;135) is out of engagement with the central opening (89;127), and the star member (31) is permitted to orbit and rotate in the normal manner.

Gerotor motor and parking lock assembly therefor

A gerotor motor (11) of the type having a spool valve (45) disposed opposite a main drive shaft (35). The motor also includes a set of brake discs (104) in engagement with an extension (45e) of the spool valve (45), and a set of brake discs (106) in engagement with internal splines (108) defined by an end cap (41). A piston (109) operable to engage the brake discs (104,106) is disposed in a chamber defined by the valve housing section (19), disposed adjacent the end cap (41). A valve drive shaft (57) having splines (53) engaging the main drive shaft (35) at its rotating end (33), also has splines (55) engaging the spool valve (45) to transmit the pure rotation of the drive shaft (35) to the spool valve (45). The result is a very compact valve drive and brake arrangement.

Gerotor motor and improved valve drive and brake assembly therefor

A gerotor motor (11) of the type having a spool valve (51) which is formed integrally with the output shaft (49), wherein the spool valve includes forward (67) and rearward (69) journal surfaces. Disposed radially between the output shaft (49) and a bearing-receiving portion (71) of the motor housing (13) is a ball bearing set (73), which is preloaded during assembly such that the rated side load on the output shaft (49) will not cause any substantial radial movement of the shaft within the bearing set (73). In order to reduce the length, and cost of the motor (11), the conventional wear plate adjacent the gerotor gear set (15) has been eliminated, such that both the valve housing (13) and the spool valve (51) are disposed immediately adjacent the gerotor gear set, and the rotating spool valve (51) is in engagement with the orbiting and rotating star member (27).

Growing community of inventors

Burnsville, MN, United States of America

Scott E Yakimow