Abstract: A skid steer loader having a main frame supported on four wheels, and a cab with upwardly extending side walls mounted on the main frame for providing an area in which an operator can control the loader. The loader is propelled by an engine operatively coupled to the wheels by a first assembly of suitable control components. A boom structure comprising a pair of arms and a mounting assembly is also mounted on the frame. A second assembly of suitable components is also coupled to the engine to provide appropriate control of the boom structure for raising and lowering the pair of arms. The first assembly of control components includes a pair of hydraulic motors for driving the wheels, and a system associated with the motors for selectively changing the speed ranges of the motors to change the speed at which the wheels propel the loader.

Abstract: A skid steer loader having a main frame supported on four wheels and including a compartment in which an engine, hydraulic drive components and other elements are contained. A cab is mounted above the compartment on the main frame with side walls extending upwardly to define an operator control area therebetween. Supported on the frame is a boom structure including a pair of arms and a mounting assembly. The engine is operatively associated with the wheels for propelling the loader. The engine is also operatively associated with the boom structure for raising and lowering the pair of arms. The wheels are controlled by a pair of hand actuated levers in the operator control area, while boom control is convertible between a foot actuated control lever in the operator control area and a hand operated element pivotally operative on one of the hand actuated levers.

Abstract: A skid steer loader having a main frame including a compartment in which an engine, hydraulic drive components and other elements are contained. A cab is mounted above the compartment on the main frame with load bearing side walls extending upwardly to define an operator control area therebetween. Pivotally mounted on such walls is a boom structure including a pair of arms and a mounting assembly. An engine is operatively associated with the boom structure for raising and lowering each of the pair of arms along a generally vertical path adjacent a corresponding load bearing side wall to which it is coupled by the mounting assembly. A unique noise isolation mounting arrangement is used to couple the cab structure to the main frame, on which cab the entire boom structure is mounted.

Abstract: A skid steer loader having a frame, ground support wheels extending from the frame, a cab with load bearing side walls extending upwardly from the frame to define an operators control area therebetween, and a boom structure comprising a pair of arms and a linkage assembly for operatively coupling the arms to the load bearing side walls. Each arm includes a front portion having a front end extending beyond the cab to support a bucket, a rear portion extending behind the cab, and an integral intermediate portion between the front and rear portions. The linkage assembly includes upper and lower links associated with each of the arms, each link being pivotally secured to the cab at a location above the wheels. The boom structure is powered for raising and lowering in concert each of the pairs of arms through a generally vertical path for moving the front end of the boom arms and bucket along a lift path.

Abstract: A skid steer loader having a main frame including a compartment in which an engine and transmission components are contained, ground support wheels extending from the main frame, and a cab mounted on the main frame. The cab includes load bearing side walls extending upwardly from the main frame to define an operators control area therebetween. A boom assembly comprising a pair of arms having material handling front portions and linkage structure that operatively attaches the arms to the cab side walls. The linkage structure includes an upper link coupled to each of the arms and pivotally secured to the cab at a location above the top surface of the wheels, and a lower link which is also pivotally secured to the cab at a location above the wheels.

Abstract: A diesel engine preheat system includes a temperature sensor for sensing the temperature of the engine coolant, engine heaters for heating the engine, and a microprocessor for calculating the duration of a preheat cycle. When an ignition switch is turned on, the microprocessor samples the output of the temperature sensor to determine the initial engine temperature. The microprocessor computes the required heating time from the initial temperature and a stored parameter representing the relationship between increase in temperature and heating time of the engine. The microprocessor energizes a relay to connect the engine heaters to a battery for the computed time. During the preheat cycle the microprocessor decrements the computed heating time and energizes a visual display to display the time remaining in the preheat cycle.

Abstract: A loader having an engine operably startable in conjunction with the closing of an associated electrical circuit, hydraulically operated boom and bucket mechanisms controllable from the operator seat, and an interlock mechanism requiring a proper sequencing of seat and seat belt switches to enable operation of the engine and hydraulic system is disclosed wherein the electrical circuit is provided with a service override feature that permits the engine to be started without undergoing the proper sequencing of the seat and seat belt switches. Whenever the contrtoller electrical circuit is placed into the service override mode, the hydraulic system cannot be enabled. The service override switch is interconnected with the normal operation switch so that both switches cannot be closed at the same time.

Abstract: A method of controlling the operation of a loader to encourage the use of an operator restraint mechanism is disclosed wherein a first signal is generated by a seat sensor to indicate the presence of the operator in the operator seat and a second signal is generated by a sensor in the operator restraint mechanism to indicate use of the mechanism. The hydraulic system will not be enabled unless the second signal is generated immediately subsequent to the generation of the first signal. Unless the first and second signals are generated in the proper sequence, the starting of the engine will also be disabled. The generation of first and second inverse signals, indicating the lack of the presence of the operator in the seat and the disengagement of the operator restraint mechanism, respectively, will disable the loader hydraulic system.

Abstract: A loader having hydraulically operated boom and bucket mechanisms controllable from the operator seat is disclosed wherein switches sense the presence of the operator in the seat and the buckling of the seat belt. An electronic controller is operably associated with the seat and belt switches and solenoid valves in the hydraulic system and the starter relay. The controller requires proper sequencing of the activation of the seat and belt switches before permitting the starter to be energized, thereby controlling the starting of the loader engine, or permitting the energizing of the hydraulic solenoid valves to control the flow of hydraulic fluid to the hydraulic cylinders for the boom and bucket. The controller also includes a delay associated with the seat switch so that a reactivation of the seat switch within the delayed period of time would allow the hydraulic system to operate without requiring a resequencing of the activation of the seat and belt switches.