Hydraulic motor with brake assembly

A hydraulic device, comprising:

• an axially-extending housing;
• a hydraulic motor at one end of the housing having a stator and a rotor with cooperating teeth defining fluid pockets, a wobble shaft connected to said rotor, said rotor rotating and orbiting relative to said stator when hydraulic fluid is directed into and out of the fluid pockets;
• an axially-extending output shaft extending outward from another end of the housing, the output shaft having an inner end portion located in the housing and connected to said wobble shaft to rotate said output shaft upon rotation and orbital movement of said rotor;
• a brake assembly axially disposed between the one end and the other end of the housing including i) a plurality of annular brake disks interleaved in face-to-face relation with one another, at least some of said disks being fixed to the output shaft for rotation therewith, and other of said brake disks being fixed to the housing;
• ii) an annular piston surrounding the output shaft and axially moveable with respect thereto;
• and iii) a series of compression springs normally biased against one annular surface of the piston to urge said piston toward and against the brake disks to cause said brake disks to brake the output shaft;
• an annular fluid pressure cavity defined by another surface of the piston axially-opposite from the one surface to move the piston away from the brake disks when fluid above the force of the springs enters the cavity;
• said housing including a) a unitary, one-piece housing cover at the other end of the housing having a central opening for the output shaft, said housing cover having a cup-shape and receiving and at least partially enclosing the brake disks and the annular piston, and b) a unitary, one-piece housing body toward the one end of the housing having a series of axially-extending cylindrical cavities to receive the compression springs, the cup-shaped housing cover and housing body sealingly enclosing the brake disks, annular piston and compression springs therebetween.

A hydraulic device, comprising:

• an axially-extending housing;
• a hydraulic motor at one end of the housing having a stator and a rotor with cooperating teeth defining fluid pockets, a wobble shaft connected to said rotor, said rotor rotating and orbiting relative to said stator when hydraulic fluid is directed into and out of the fluid pockets;
• an axially-extending output shaft extending outward from another end of the housing, the output shaft having an inner end portion located in the housing and connected to said wobble shaft to rotate said output shaft upon rotation and orbital movement of said rotor;
• a brake assembly axially disposed between the one end and the other end of the housing including i) a plurality of annular brake disks interleaved in face-to-face relation with one another, at least some of said disks being fixed to the output shaft for rotation therewith, and other of said brake disks being fixed to the housing;
• ii) an annular piston surrounding the output shaft and axially moveable with respect thereto;
• and iii) at least one spring device normally biased against one annular surface of the piston to urge said piston toward and against the brake disks to cause said brake disks to brake the output shaft;
• an annular fluid pressure cavity defined by another surface of the piston axially-opposite from the one surface to move the piston away from the brake disks when fluid above the force of the spring device enters the cavity, the spring device provided toward the one end of the housing, the brake disks provided toward the other end of the housing, and the piston disposed axially between the spring device and the brake disks.

A hydraulic device, comprising:

• an axially-extending housing;
• a hydraulic motor at one end of the housing having a stator and a rotor with cooperating teeth defining fluid pockets, a wobble shaft connected to said rotor, said rotor rotating and orbiting relative to said stator when hydraulic fluid is directed into and out of the fluid pockets;
• an axially-extending output shaft extending outward from another end of the housing, the output shaft having an inner end portion located in the housing and connected to said wobble shaft to rotate said output shaft upon rotation and orbital movement of said rotor;
• a brake assembly axially disposed between the one end and the other end of the housing including i) a plurality of annular brake disks interleaved in face-to-face relation with one another, at least some of said disks being fixed to the output shaft for rotation therewith, and other of said brake disks being fixed to the housing;
• ii) an annular piston surrounding the output shaft and axially moveable with respect thereto;
• and iii) at least one spring device normally biased against one annular surface of the piston to urge said piston toward and against the brake disks to cause said brake disks to brake the output shaft;
• an annular fluid pressure cavity defined by another surface of the piston axially-opposite from the one surface to move the piston away from the brake disks when fluid above the force of the spring device enters the cavity;
• an annular seal surrounding the output shaft and blocking flow between the brake assembly and the hydraulic motor;
• and
• a thrust bearing disposed adjacent the inner end of the output shaft in fluid communication with the hydraulic motor, said thrust bearing disposed between radially-extending and opposing bearing surfaces formed in the housing and in the output shaft, said thrust bearing at least partially axially supporting the inner end portion of said output shaft for rotation relative to the housing.

A hydraulic device, comprising:

• an axially-extending housing;
• a hydraulic motor at one end of the housing, and a drive linkage to operate the motor, the drive linkage including an axially-extending output shaft extending outward from another end of the housing, the output shaft rotating upon operation of the motor;
• a brake assembly axially disposed between the one end and the other end of the housing including i) a plurality of annular brake disks interleaved in face-to-face relation with one another, at least some of said disks being fixed to the output shaft for rotation therewith, and other of said brake disks being fixed to the housing;
• ii) an annular piston surrounding the output shaft and axially moveable with respect thereto;
• and iii) a series of compression springs normally biased against one annular surface of the piston to urge said piston toward and against the brake disks to cause said brake disks to brake the output shaft;
• an annular fluid pressure cavity defined by another surface of the piston axially-opposite from the one surface to move the piston away from the brake disks when fluid above the force of the springs enters the cavity, said piston including a radially-projecting stop surface across a major portion of the one surface of the piston and the housing including a corresponding radially-projecting stop surface, the stop surface of the piston engaging the stop surface of the housing prior to maximum compression of the springs, wherein the piston is prevented from cocking when the stop surface of the piston contacts the stop surface of the housing, the compression springs provided toward the one end of the housing, the brake disks provided toward the other end of the housing, and the piston disposed axially between the compression springs and the brake disks;
• a thrust bearing disposed adjacent the inner end of the output shaft in fluid communication with the hydraulic motor, said thrust bearing disposed between radially-extending and opposing bearing surfaces formed in the housing and in the output shaft, said thrust bearing at least partially axially supporting the inner end portion of said output shaft for rotation relative to the housing;
• said housing including a) a unitary, one-piece housing cover at the other end of the housing having a central opening for the output shaft, said housing cover having a cup-shape and receiving and at least partially enclosing the brake disks and the annular piston, and b) a unitary, one-piece housing body toward the one end of the housing having a series of axially-extending cylindrical cavities to receive the compression springs, the cup-shaped housing cover and housing body sealingly enclosing the brake disks, annular piston and compression springs therebetween.