A crawler drive unit relating to one aspect of the present disclosure includes a speed reduction mechanism provided in a running unit for causing a vehicle body to run, where the speed reduction mechanism is configured to transmit a driving force to a crawler provided on the running unit, a transmission mechanism for transmitting the driving force to the speed reduction mechanism, and an electric motor for applying a rotational force to the transmission mechanism. A motor shaft of the electric motor is positioned higher than a rotational axis of an input shaft of the speed reduction mechanism.

A drive transmission device according to one embodiment of the disclosure includes a single differential unit to which rotation of a motor is transmitted and two speed reducers each having an operation output shaft that is coupled to the differential unit and a carrier that changes a speed of the rotation of the operation output shaft and outputs the rotation. The two speed reducers are arranged such that they are opposed to each other along a second rotation axis, and the operation output shaft and the carrier in each speed reducer are aligned in the second rotation axis direction.

A speed reducer according to one aspect of the present disclosure includes: speed reducing units for decelerating a rotational driving force of an electric motor and transmitting the decelerated rotational driving force to a rotational driving unit; and a ring gear meshing with a gear decelerated by a speed reducing unit on the electric motor side in a direction of a rotational axis of the electric motor. The ring gear is provided with a water-cooling channel that communicates cooling water. The water-cooling channel includes a first groove having a small depth and a second groove having a larger depth and extends in a C-shape as the ring gear is viewed from the direction of the rotational axis. The ring gear is provided with a motor flange mounted to the electric motor. The motor flange is provided with an inlet port and an outlet port connected to the water-cooling channel.

A drive transmission device in one embodiment of the disclosure includes a pair of output shafts, a differential, a clutch (power transmission unit), and a control unit. The pair of output shafts connected to a pair of speed reducers that are disposed to face each other. The differential receives a driving force from a drive source and outputs the driving force to the pair of output shafts; The clutch acts on the differential and takes a first state in which a load imbalance between the pair of output shafts is adjusted or a second state in which the pair of output shafts are rotated directly by the driving force. The control unit switches the state of the clutch based on difference information regarding a difference in rotation between the pair of speed reducers.

Provided is a speed reducer including: a first reduction unit disposed at an input stage of a multi-stage reduction unit that decelerates a rotational driving force of an electric motor from an input stage side toward an output stage side and transmits the decelerated rotational driving force to a rotational drive unit; a first ring gear meshed with first planetary gears provided in the first reduction unit; and a third reduction unit disposed at an output stage of the multi-stage reduction unit and having a first case. The first ring gear is provided in the first case of the third reduction unit.

A housing for a final drive, the housing being capable of reducing invasion of foreign materials into a labyrinth channel by a simple configuration, and easily discharging out foreign materials in the labyrinth channel, and a final drive provided with the housing. A labyrinth channel 52 is provided at a position facing a floating seal 51 for sealing a gap between a stationary-side housing 26 and a rotation-side housing 25. Slits 39 for discharging out foreign materials are provided. The slits 39 communicate with the labyrinth channel 52 and are provided around an outer periphery portion of a cylinder-shaped housing main body 38 of the stationary-side housing 26 in such a way that the slits 39 are located in an area located in a lower part or one edge portion along the driving direction in a lower half portion of the housing main body 38.

To control elevation of the temperature of the reducing agent in a reducing agent tank which is located near a heat generating control valve in a construction machine, a tank storage room 8 housing a urea aqueous tank is located at the upper side of a valve housing room where control valves are housed. The urea aqueous tank is mounted at the upper side of a bulkhead plate which separates a tank storage room and the valve housing room one above the other having an empty space between so that air can flows through an air flow path S, and a space A is provided between a cover body covering the tank storage room and a cover body covering the valve housing room so that the air flows in and out through the space A and the air flow path S.

The present disclosure relates to a frame assembly of a heavy duty vehicle including an operator cabin. The frame assembly may comprise a superstructure frame having a first flange at least partially protruding from the cabin supporting frame mounting portion and having a collar and a plurality of first flange bores. The frame assembly may further comprise a cabin supporting frame having a first mounting section including a plurality of first mounting section bores, a first guiding member, and a second guiding member. The first and second guiding members may be configured to engage the collar for safely guiding the cabin supporting frame relative to the superstructure frame into a final assembling in which the plurality of first flange bores may be aligned with the plurality of first mounting section bores.

Provided is a construction machine including an exhaust-gas after-treatment device and capable of supporting the exhaust-gas after-treatment device in a limited space. The construction machine includes an upper frame, an engine mounted on the upper frame via a plurality of engine mounts, a hydraulic pump coupled to the engine, the exhaust-gas after-treatment device, and a support cradle supporting the exhaust-gas after-treatment device over the hydraulic pump. The upper frame includes a plurality of mount support portions and a leg support portion. The support cradle includes a support stage on which the exhaust-gas after-treatment device is mounted, and a plurality of legs. The plurality of mount support portions include a space-defining mount support portion defining a horizontal space against the hydraulic pump. The plurality of legs include an in-space leg extending in the space. The leg support portion is located to overlap the space in a plan view.

In a power control device, when the necessary power is greater than an upper limit value and either the integral power value or the duration time of an assist provided by an electric storage device during a continuous assist by the electric storage device exceeds a predetermined first threshold value, a controller performs a first control of reducing an assist power by the electric storage device to a value smaller than an assist power for the regular control and greater than zero. Further, when the necessary power is greater than the upper limit value and either the integral power value or the duration time exceeds a predetermined second threshold value greater than the first threshold value, the controller performs a second control of setting the assist power to zero.