Abstract: A construction vehicle includes an engine, a hydraulic pump configured to be driven by the engine, a traveling hydraulic motor configured to be driven by pressured oil discharged by the hydraulic pump, a traveling wheel configured to be driven by driving force of the traveling hydraulic motor, and a control unit configured to control a vehicle velocity and a traction force by controlling rotation speed of the engine, capacity of the hydraulic pump, and capacity of the traveling hydraulic motor. In addition, the control unit is further configured to perform slip reduction control for reducing the maximum rotation speed of the engine as the vehicle velocity becomes slow in a low-velocity range in which the vehicle velocity is less than or equal to a predetermined velocity.

Abstract: The present invention discloses methods to produce large quantities of polycrystalline GaN for use in the ammonothermal growth of group III-nitride material. High production rates of GaN can be produced in a hydride vapor phase growth system. One drawback to enhanced polycrystalline growth is the increased incorporation of impurities, such as oxygen. A new reactor design using non-oxide material that reduces impurity concentrations is disclosed. Purification of remaining source material after an ammonothermal growth is also disclosed. The methods described produce sufficient quantities of polycrystalline GaN source material for the ammonothermal growth of group III-nitride material.

Abstract: The present disclosure proves for new design of reactors used for ammonothermal growth of III nitride crystals. The reactors include a region intermediate a source dissolution region and a crystal growth region configured to provide growth of high quality crystals at rates greater than 100 ?m/day. In one embodiment, multiple baffle plates having openings whose location is designed so that there is no direct path through the intermediate region, or with multiple baffle plates having differently sized openings on each plate so that the flow is slowed down and/or exhibit greater mixing are described. The disclosed designs enables obtaining high temperature difference between the dissolution region and the crystallization region without decreasing conductance through the device.

Abstract: In the construction vehicle, a controller is configured to implement a displacement rapid change suppression control for controlling the displacement of a travel hydraulic pump so that travel circuit oil pressure reaches a maximum value equal to or less than a cutoff pressure value when the vehicle has stopped regardless of engine speed, and the displacement of the travel hydraulic pump gradually increases as the travel circuit oil pressure decreases from the maximum value.

Abstract: The present invention discloses a high-pressure vessel of large size formed with a limited size of e.g. Ni—Cr based precipitation hardenable superalloy. The vessel may have multiple zones. For instance, the high-pressure vessel may be divided into at least three regions with flow-restricting devices and the crystallization region is set higher temperature than other regions. This structure helps to reliably seal both ends of the high-pressure vessel, and at the same time, may help to greatly reduce unfavorable precipitation of group III nitride at the bottom of the vessel. This invention also discloses novel procedures to grow crystals with improved purity, transparency and structural quality. Alkali metal-containing mineralizers are charged with minimum exposure to oxygen and moisture until the high-pressure vessel is filled with ammonia. Several methods to reduce oxygen contamination during the process steps are presented.

Abstract: The construction vehicle includes an engine, an accelerator pedal, a main pump configured to be driven by the engine, first and second traveling motors driven by pressured oil discharged from the main pump to generate driving force for traveling, a driving shaft configured to receive the driving force from the first traveling motor and the driving force from the second traveling motor, a clutch configured to switch between transmission and non-transmission of the driving force from the second traveling motor to the driving shaft, an accelerator opening degree detection unit, a vehicle velocity detection unit, and a control unit. The control unit is configured to determine the switchover velocity depending on the opening degree of the accelerator pedal, and to control the clutch when the vehicle velocity that is detected by the vehicle velocity detection unit reaches the switchover velocity.

Abstract: The present invention discloses a new testing method of group III-nitride wafers. By utilizing the ammonothermal method, GaN or other Group III-nitride wafers can be obtained by slicing the bulk GaN ingots. Since these wafers originate from the same ingot, these wafers have similar properties/qualities. Therefore, properties of wafers sliced from an ingot can be estimated from measurement data obtained from selected number of wafers sliced from the same ingot or an ingot before slicing. These estimated properties can be used for product certificate of untested wafers. This scheme can reduce a significant amount of time, labor and cost related to quality control.

Abstract: The present invention discloses methods to create higher quality group III-nitride wafers that then generate improvements in the crystalline properties of ingots produced by ammonothermal growth from an initial defective seed. By obtaining future seeds from carefully chosen regions of an ingot produced on a bowed seed crystal, future ingot crystalline properties can be improved. Specifically, the future seeds are optimized if chosen from an area of relieved stress on a cracked ingot or from a carefully chosen N-polar compressed area. When the seeds are sliced out, miscut of 3-10° helps to improve structural quality of successive growth. Additionally a method is proposed to improve crystal quality by using the ammonothermal method to produce a series of ingots, each using a specifically oriented seed from the previous ingot. When employed, these methods enhance the quality of Group III nitride wafers and thus improve the efficiency of any subsequent device.

Abstract: A construction vehicle includes an engine, a hydraulic pump configured to be driven by the engine, a traveling hydraulic motor configured to be driven by pressured oil discharged by the hydraulic pump, a traveling wheel configured to be driven by driving force of the traveling hydraulic motor, and a control unit configured to control a vehicle velocity and a traction force by controlling rotation speed of the engine, capacity of the hydraulic pump, and capacity of the traveling hydraulic motor. In addition, the control unit is further configured to perform slip reduction control for reducing the maximum rotation speed of the engine as the vehicle velocity becomes slow in a low-velocity range in which the vehicle velocity is less than or equal to a predetermined velocity.

Abstract: The present invention discloses a production method for group III nitride ingots or pieces such as wafers. To solve the coloration problem in the wafers grown by the ammonothermal method, the present invention composed of the following steps; growth of group III nitride ingots by the ammonothermal method, slicing of the ingots into wafers, annealing of the wafers in a manner that avoids dissociation or decomposition of the wafers. This annealing process is effective to improve transparency of the wafers and/or otherwise remove contaminants from wafers.

Abstract: The construction vehicle includes an engine, an accelerator pedal, a main pump configured to be driven by the engine, first and second traveling motors driven by pressured oil discharged from the main pump to generate driving force for traveling, a driving shaft configured to receive the driving force from the first traveling motor and the driving force from the second traveling motor, a clutch configured to switch between transmission and non-transmission of the driving force from the second traveling motor to the driving shaft, an accelerator opening degree detection unit, a vehicle velocity detection unit, and a control unit. The control unit is configured to determine the switchover velocity depending on the opening degree of the accelerator pedal, and to control the clutch when the vehicle velocity that is detected by the vehicle velocity detection unit reaches the switchover velocity.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: The invention provides a working unit control apparatus of an excavating and loading machine which can always judge a start of an excavation control at a proper timing. The working unit control apparatus has excavating state detecting means (43, 44) detecting an excavating state of a vehicle, and a controller (25) has a load judging portion (48) judging on the basis of a detecting amount, and automatic excavation control means (51) setting and outputting an automatic excavation command value to each of control valves on the basis of the judgement of said load judging portion, and an automatic excavation control is started when a boom lever is operated and it is judged that a vehicle is under excavation.

Abstract: An apparatus for controlling a plurality of hydraulic motors and a clutch is capable of reliably implementing a sequence for engaging and disengaging the clutch and for fixing and clearing a zero tilt rotation amounts of the hydraulic motors, thereby preventing a speed change shock or load slip in the hydraulic motors. The apparatus includes zero tilt rotation fixing means (10A), a clutch (5), hydraulic vehicle speed detecting means (32A), and control valve means (30A) that releases an output command pressure to a return pressure connected to a tank (19) until a vehicle speed signal pressure to be received reaches a start pressure of a predetermined value, and begins to output the command pressure to the zero tilt rotation fixing means and the clutch when the vehicle speed signal pressure exceeds a predetermined value.

Abstract: An apparatus for controlling a plurality of hydraulic motors and a clutch is capable of reliably implementing a sequence for engaging and disengaging the clutch and for fixing and clearing a zero tilt rotation amounts of the hydraulic motors, thereby preventing a speed change shock or load slip in the hydraulic motors. The apparatus includes zero tilt rotation fixing means (10A), a clutch (5), hydraulic vehicle speed detecting means (32A), and control valve means (30A) that releases an output command pressure to a return pressure connected to a tank (19) until a vehicle speed signal pressure to be received reaches a start pressure of a predetermined value, and begins to output the command pressure to the zero tilt rotation fixing means and the clutch when the vehicle speed signal pressure exceeds a predetermined value.