Miniature joystick mounted on a joystick

Abstract

A hand-operated dual joystick for a motor grader is disclosed. The dual joystick comprises a first joystick having a ledge and a switch, and a second joystick that is significantly smaller than the first joystick. The second joystick is mounted to the ledge of the first joystick. The first joystick is moveable along a first axis and a second axis that are perpendicular to each other. In addition, the first joystick is rotatable about a third axis that is perpendicular to the first axis and to the second axis. The second joystick is moveable along the first axis and the second axis. Movement of the first joystick and the second joystick is used to control a plurality of motor grader functions. The dual function joystick permits an operator to control a plurality of the motor grader functions from a single location thus reducing operator fatigue.

We claim: 
     
       1. A hand-operated control for a motor grader comprising: a dual joystick having a first joystick and a second joystick;   said first joystick including a control switch and a ledge; and   said second joystick being significantly smaller than said first joystick and mounted on said ledge of said first joystick.   
     
     
       2. A hand-operated control for a motor grader as recited in claim 1 further comprising an electronic control computer and wherein said first joystick is movable on a first axis and a second axis; said first axis perpendicular to said second axis;   said first joystick rotatable about a third axis, said third axis perpendicular to both said first axis and said second axis; and   movement of said first joystick on said first axis, said second axis, or about said third axis generating a plurality of electrical input signals, said plurality of electrical input signals detected by said electronic control computer.   
     
     
       3. A hand-operated control for a motor grader as recited in claim 2 further comprising a plurality of electro-hydraulic actuators each having a drive solenoid wherein said electronic control computer generates a control signal in response to each of said input signals, said electronic control computer transmitting said control signal to at least one of said electro-hydraulic actuators. 
     
     
       4. A hand-operated control for a motor grader as recited in claim 3 further comprising a hydraulic right lift cylinder and a hydraulic left lift cylinder, each of said hydraulic right lift cylinder and said hydraulic left lift cylinder associated with at least one of said plurality of electro-hydraulic actuators and wherein said electronic control computer transmits one of said control signals to each of said associated electro-hydraulic actuators of said hydraulic right lift cylinder and said hydraulic left lift cylinder in response to movement of said first joystick on said first axis. 
     
     
       5. A hand-operated control for a motor grader as recited in claim 3 further comprising a hydraulic side shift cylinder, said hydraulic side shift cylinder associated with at least one of said plurality of electro-hydraulic actuators and wherein said electronic control computer transmits one of said control signals to said associated electro-hydraulic actuator of said hydraulic side shift cylinder in response to movement of said first joystick on said second axis. 
     
     
       6. A hand-operated control for a motor grader as recited in claim 3 further comprising a hydraulic circle drive, said hydraulic circle drive associated with at least one of said plurality of electro-hydraulic actuators and wherein said electronic control computer transmits one of said control signals to said associated electro-hydraulic actuator of said hydraulic circle drive in response to rotation of said first joystick about said third axis. 
     
     
       7. A hand-operated control for a motor grader as recited in claim 1 further comprising an electronic control computer and wherein said second joystick is movable on a first axis and a second axis; said first axis perpendicular to said second axis; and   movement of said second joystick on said first axis or said second axis generating a plurality of electrical input signals, said plurality of electrical input signals detected by said electronic control computer.   
     
     
       8. A hand-operated control for a motor grader as recited in claim 7 further comprising a plurality of electro-hydraulic actuators each having a drive solenoid wherein said electronic control computer generates a control signal in response to each of said input signals, said electronic control computer transmitting said control signal to at least one of said electro-hydraulic actuators. 
     
     
       9. A hand-operated control for a motor grader as recited in claim 8 further comprising a hydraulic blade tip cylinder, said hydraulic blade tip cylinder associated with at least one of said plurality of electro-hydraulic actuators and wherein said electronic control computer transmits one of said control signals to said associated electro-hydraulic actuator of said hydraulic blade tip cylinder in response to movement of said second joystick on said first axis. 
     
     
       10. A hand-operated control for a motor grader as recited in claim 8 further comprising a hydraulic center shift cylinder, said hydraulic center shift cylinder associated with at least one of said plurality of electro-hydraulic actuators and wherein said electronic control computer transmits one of said control signals to said associated electro-hydraulic actuator of said hydraulic center shift cylinder in response to movement of said second joystick on said second axis.