JP5421225B2 - Work machine, electrical control unit, and inverter - Google Patents

Description

  The present invention relates to a work machine such as a construction machine having a turning body that is driven to turn by an electric motor, an electric control unit mounted on the work machine, and an inverter.

  In recent years, for example, in a hydraulic excavator as a working machine, working machines such as a boom, an arm, and a bucket are driven by hydraulic oil from a hydraulic pump driven by an engine, and the upper swing body is driven to rotate by an electric motor. Hybrid hydraulic excavators are actively developed (see Patent Document 1).

  In such a hybrid work machine, a capacitor that charges electric power generated by a generator motor, electric power regenerated by an electric motor, and an inverter that controls charging of the capacitor and electric power supply from the capacitor to the electric motor. Is provided. The capacitor and the inverter are unitized as one unit to constitute an electric control unit.

  In the electric control unit, the capacitor and inverter generate heat during operation of the generator motor and the electric motor. Therefore, the electric control unit is cooled not only by the circulating coolant but also by the cooling air taken in by the fan in the vehicle from outside the vehicle. To be cooled.

International Publication No. 2008/015798 Pamphlet

A hybrid hydraulic excavator is equipped with components such as a generator motor, a capacitor, and an inverter. In addition, a capacitor and an inverter require a cooling device to prevent deterioration due to heat generation of the capacitor and damage of electronic equipment due to heat generation of the inverter. However, in recent years, it has become necessary to increase the size of the electric control unit (larger in the front-rear, left-right, and upward directions) due to the increase in capacitor capacity due to the higher output of work machines and the pursuit of lower fuel consumption. However, the electric control unit blocks the flow of cooling air to the radiator, which is a cooling device, and there is a problem that the cooling capacity of the radiator is hindered.

  An object of the present invention is to provide a work machine, an electric control unit, and an inverter that can satisfactorily supply cooling air to a radiator even when the electric control unit is enlarged.

A work machine according to a first aspect of the present invention is a work machine including an electric control unit disposed in a cooling air inflow path and a radiator cooled by the cooling air, the electric control unit including a generator A capacitor for charging the electric power generated by the motor; and charging the electric power to the electric accumulator and controlling the output of the charged electric power from the electric accumulator to the electric motor, and an inverter mounted on the electric accumulator A terminal box to which a cable for power transmission to and from the inverter is connected is provided on the capacitor, and the cable, for power transmission from the generator motor are provided on the inverter. And a terminal case to which a cable for power transmission to the electric motor is connected, and the terminal case of the inverter Between the terminal box of the serial accumulator, the cooling air recesses passing through is provided toward the radiator, at least one of said terminal case and said terminal box, the opposing surface facing the radiator, It is inclined with respect to the flow direction of the cooling air passing through the recess.

In the work machine according to the second aspect of the present invention, in both the terminal case and the terminal box, the facing surface facing the radiator is inclined with respect to the flow direction of the cooling air passing through the recess . Each of the opposing surfaces is widened to the radiator side with the concave portion interposed therebetween.

  In the work machine according to a third aspect of the present invention, a pair of the opposing surfaces are arranged in the horizontal direction so that the boundary portions of the opposing surfaces protrude toward the radiator.

  An electric control unit according to a fourth aspect of the present invention is an electric control unit arranged in an inflow path of cooling air to a radiator mounted on a work machine, wherein the electric control unit is electric power generated by a generator motor. A storage battery, and charging the power to the storage battery and controlling the output of the charged power from the storage battery to an electric motor, and an inverter mounted on the storage battery, A terminal box to which a cable for power transmission to and from the inverter is connected is provided on the battery, and the cable, a cable for power transmission from the generator motor, and the cable are provided on the inverter. A terminal case to which a cable for power transmission to the electric motor is connected is provided, and the terminal case of the inverter and the capacitor Between the terminal box, a recess through which the cooling air passes toward the radiator is provided, and in at least one of the terminal case and the terminal box, an opposing surface facing the radiator is provided with the recess. The cooling air is inclined with respect to the flow direction of the cooling air passing therethrough.

  An inverter according to a fifth aspect of the invention is disposed in a cooling air inflow path to a radiator mounted on a work machine, is placed on a capacitor that charges power generated by a generator motor, and the power generation An inverter that controls charging of electric power generated by a motor to the electric accumulator and output of charged electric power from the electric accumulator to the electric motor, the electric power transmission cable to and from the electric accumulator, the generator A terminal case to which a power transmission cable from the motor and a power transmission cable to the electric motor are connected is provided, and a facing surface of the terminal case facing the radiator is provided on the capacitor. Inclined with respect to the flow direction of the cooling air passing between the terminal box and the terminal box.

  According to the work machine, the electric control unit, and the inverter according to the first invention, the fourth invention, and the fifth invention, the cooling air flowing toward the radiator is an inverter, and further, the electric control configured by the inverter and the capacitor. Although it is obstructed by the unit, since the facing surface of the inverter facing the radiator is inclined with respect to the flow direction of the cooling air, the cooling air easily flows along the facing surface when passing through the facing surface. , It begins to flow with spread toward the radiator. Therefore, even if the electric control unit is enlarged, the cooling air can be efficiently supplied to the radiator.

1 is a block diagram showing a schematic configuration of a work machine according to an embodiment of the present invention. The perspective view which shows the principal part of the said working machine. The top view which expands and shows the said principal part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In FIG. 1, a hybrid excavator 1 as a work machine includes an engine 2 as a drive source. A generator motor 3 and a pair of hydraulic pumps 4, 4 are connected in series to the output shaft of the engine 2, and are driven by the engine 2.

  The electric power generated by the generator motor 3 is charged into a capacitor 6 as a battery via an inverter 5. The electric power charged in the capacitor 6 is boosted by the booster 5 </ b> A and output to the swing electric motor 7 through the inverter 5. The turning electric motor 7 drives the upper turning body 9 via a speed reducer 8 having a planetary gear mechanism or the like.

  On the other hand, the hydraulic oil pumped from the hydraulic pump 4 is supplied to the work machine 11 via the control valve 10. The work machine 11 in the hybrid excavator 1 includes a boom, an arm, and a bucket (not shown), and the hydraulic oil flows out to hydraulic cylinders such as a boom cylinder 12, an arm cylinder 13, and a bucket cylinder 14 provided in each. By making it enter, the work machine 11 operates by hydraulic pressure.

  The vehicle body of the hybrid excavator 1 is provided with a pair of crawler-type lower traveling bodies 15 (FIG. 2), although detailed illustration is omitted. The lower traveling body 15 has a traveling hydraulic motor 16 for driving a sprocket that meshes with the crawler. The hydraulic oil from the hydraulic pump 4 is also supplied to the hydraulic motor 16 via the control valve 10. Supplied. In addition, the above-described upper swing body 9 is installed on the upper portion of the lower traveling body 15 so as to be rotatable.

  Therefore, the hybrid excavator 1 of the present embodiment is a hybrid construction machine that drives the upper swing body 9 to swing with electric energy and drives the work implement 11 and the lower traveling body with hydraulic pressure. Each configuration described above is mounted on the upper swing body 9 except for the traveling hydraulic motor 16, and rotates together with the upper swing body 9.

  In FIG. 2, an engine room 18 covered with a counterweight 35 and an exterior cover 17 is provided on the vehicle rear side of the upper swing body 9. The position of the upper swing body 9 corresponding to the upper side of the engine room 18 is an engine hood 19 that constitutes the exterior cover 17. By opening the engine hood 19 upward, the engine 2 and the like can be maintained. is there. An inspection door 20 that can be freely opened and closed is provided on the side of the upper swing body 9.

  In the engine room 18, in addition to the engine 2, the generator motor 3 and the pair of hydraulic pumps 4 described in FIG. 1, a cooling unit 21 for cooling these power units is provided in parallel along the left-right direction of the vehicle. Contained in state.

  The cooling unit 21 includes a cooling fan (not shown) driven by the engine 2 or a dedicated hydraulic motor, an electric motor, an engine radiator (first radiator) that cools engine cooling water, an oil cooler that cools hydraulic oil, an engine And an after cooler for cooling the intake air supplied to the engine, and a hybrid radiator 22 (second radiator) as a radiator according to the present invention. Among these, an engine radiator, an oil cooler, and an after cooler are used as the radiator body 23. Built in one frame.

  In this embodiment, the cooling fan is a suction type, and cooling air from the outside is taken into the engine room 18 through a louver-shaped opening 24 provided in the inspection door 20. In the engine room 18, the hybrid radiator 22 of the cooling unit 21 is located upstream of the wind flow taken into the engine room from the engine radiator. Further, the upstream side of the hybrid radiator 22 is a cooling room 25 separated from the engine room 18 by a cooling unit 21, and the cooling air first enters the cooling room 25 through the opening 24 of the inspection door 20. It is drawn in and flows into the engine room 18. A partition member (not shown) is provided in front of the vehicle in the cooling room, and a substantially sealed space is formed by the cooling unit 21, the counterweight 35, and the exterior cover 17.

  In the cooling room 25, an electric control unit 26 constituted by the inverter 5 and the capacitor 6 is accommodated. Then, by opening the inspection door 20, it is possible to inspect and maintain the electric control unit 26 in the cooling room 25. In such an electric control unit 26, the capacitor 6 is disposed on the lower side, and the inverter 5 is mounted on the upper side. The capacitor 6 is accommodated in a position one step down from the deck portion 27 </ b> A of the swing frame 27. Yes.

  The inverter 5 of the electric control unit 26 will be described more specifically. The cooler 28 is covered with upper and lower covers 29 and 30, and a terminal case 31 is attached to the upper portion of the upper cover 29. Inside the cooler 28, a flow path through which the coolant flows is formed. The booster 5 </ b> A housed in the upper cover 29 and the drive for driving the generator motor 3 housed in the lower cover 30 are formed. The element (for example, IGBT) and the drive element (for example, IGBT) for driving the swing electric motor 7 are cooled.

  On the other hand, a channel for circulating the coolant is also formed in the capacitor 6. The cooling liquid (for example, water) first cools the capacitor 6 by a pressure pump (not shown), and after cooling the capacitor 6, flows to the cooler 28 of the inverter 5, cools the inverter by the cooler 28, and then turns the electric motor 7. Is supplied to cool the swing electric motor 7. The coolant that has flowed out of the swing electric motor 7 flows into the hybrid radiator 22, exchanges heat with the cooling air, is cooled, returns to the pressure pump, and circulates again.

  A terminal box 32 is provided above the capacitor 6. The terminal box 32 has an L-shaped block shape when viewed from the side of the upper swing body 9, and a space of a recess 33 (viewed from the side of the upper swing body) is formed between the terminal box 32 and the terminal case 31 of the adjacent inverter 5. Forming. The recess 33 is provided so that the cooling air flowing in from the louver 24 is taken into the hybrid radiator 22 without being obstructed by the electric control unit 26, and is preferably provided at a position substantially corresponding to the center of the hybrid radiator 22. It has been. That is, the electric control unit 26 is arranged in the cooling air inflow path.

  Then, an opening 24 of the inspection door 20 is provided so as to face the recess 33, and most of the cooling air taken in from the opening 24 is formed in the recess 33 as indicated by an arrow A in FIG. It passes through and flows toward the center of the hybrid radiator 22 in a state where the flow velocity is increased.

  Here, the cooler 28 of the inverter 5 and the terminal box 32 of the capacitor 6 are provided with holes 34 at appropriate positions, and each hole 34 covers almost the entire area above the electric control unit 26 from above. A cover 36 is placed and fixed with mounting bolts 37. The cover 36 may be made of hard synthetic resin or metal, and may be made of flexible rubber or resin sheet. Such a cover 36 prevents dust, rainwater, and the like entering the cooling air from the opening 24 and the exterior cover 17 from being applied to the electric control unit 26. The cover 36 is preferably an insulating material.

  FIG. 3 shows a state in which the inside of the cooling room 25 is viewed in plan. In FIG. 3, four cable harnesses 41 to 44 are connected to the terminal case 31 of the inverter 5. The cable harnesses 41 and 42 are connected to the generator motor 3.

  In the present embodiment, an SR (switched reluctance) motor having a 36-pole stator and a 24-pole rotor is used as the generator motor 3. Each of the cable harnesses 41 and 42 includes three power cables 41A and 42A, and has a total of six power cables 41A and 42A. The alternating current generated by the generator motor 3 is transmitted to the inverter 5 through the cable harnesses 41 and 42. The cable harnesses 41 and 42 are held by a holding member 45, and the holding member 45 is fixed to a metal bracket 46 attached to the inverter 5.

  By being held by the holding member 45, even if the cable harnesses 41 and 42 greatly fluctuate during work, the fluttering can be prevented from affecting the end portions, and the cable harnesses 41 and 42 are not prepared from the terminal case 31. Can be prevented from occurring, or stress can be generated in the conductive terminals inside the connector, thereby preventing contact failure.

  The cable harness 43 is connected to the turning electric motor 7. The cable harness 43 is composed of three power cables 43 </ b> A, similar to the cable harnesses 41 and 42, and is used to transmit an alternating current from the inverter 5 to the swing electric motor 7.

  The cable harness 44 is connected to the terminal box 32 of the capacitor 6. The power converted from AC to DC by the inverter 5 is transmitted to the capacitor 6 to be charged, and conversely, the DC of the capacitor 6 is charged. Electric power is transmitted to the inverter 5. In such a terminal box 32, electronic components such as a contactor, a fuse, and an LED substrate are accommodated. The cable harness 44 is held by the holding member 45 together with the cable harness 43 and is fixed to the bracket 46.

  Further, a pair of connectors 47 and 47 are provided on the side surface of the inverter 5, and a cable harness for connecting to various sensors mounted on the vehicle is attached to these connectors 47. Here, illustration of those cable harnesses is omitted.

  Further, a pipe 49 for supplying a coolant from the pressure pump is connected to an inlet 48 provided in the capacitor 6. A pipe 52 is connected between the outlet 50 of the capacitor 6 and the inlet 51 of the inverter 5 to send the coolant from the capacitor 6 side to the inverter 5. A pipe 52 for sending the coolant to the swing electric motor 3 is also connected to the outlet 53 of the inverter 5.

  In the terminal case 31 of the inverter 5 and the terminal box 32 of the capacitor 6, the connection surfaces 54 to 56 of the cable harnesses 41 to 44 are facing surfaces facing the hybrid radiator 22, and the flow direction of the cooling air passing through the recess 33 (See arrow A).

  Specifically, in the terminal case 31 disposed on the vehicle rear side with respect to the recess 33, the connection surface 54 to which the cable harnesses 41 and 42 are connected in the plan view is the vehicle rear side (right side in FIG. 3). The connecting surface 55 to which the cable harnesses 43 and 44 are connected is inclined toward the inspection door 20 side of the cooling room 25 toward the front side of the vehicle. Inclined to be located.

  In plan view, the boundary between the connection surfaces 54 and 55 is formed in a triangular shape protruding toward the hybrid radiator 22 side. At this time, a central portion that is a boundary portion between the connection surfaces 54 and 55 is at a position corresponding to the vicinity of the end portion of the hybrid radiator 22 on the vehicle rear side.

  On the other hand, in the terminal case 32 arranged on the vehicle front side (left side in FIG. 3) with respect to the recess 33, the connection surface 56 to which the cable harness 44 is connected in the plan view is cooled toward the vehicle front side. It inclines so that it may be located in the engine 2 side of the room 25, and is formed in the taper shape. The portion of the connection surface 56 on the front side of the vehicle located closest to the engine 2 is at a position corresponding to the vicinity of the end portion of the hybrid radiator 22 on the front side of the vehicle.

  The inclination angle θ of each of the connection surfaces 54 to 56 with respect to the horizontal line H orthogonal to the flow direction of the arrow A is not particularly limited, but is about 10 ° in the present embodiment. Since the connection surfaces 54 to 56 are inclined at the inclination angle θ, the cooling air flowing through the recess 33 is easily diverted to the connection surfaces 55 and 56 that are spread toward the hybrid radiator 22. , C in the direction indicated by C, and cooling air is supplied to the entire hybrid radiator 22.

  Moreover, since the upper part of the electric control unit 26 is covered with the cover 36, the cooling air passing through the recess 33 can be more easily spread in combination with the inclination of the connection surfaces 55 and 56. In particular, conventionally, a pump for pumping coolant has been arranged on the hybrid radiator 22 side of the terminal box 32. However, in this embodiment, such a pump is removed from the accommodation area of the electric control unit 26. Since it is arranged at the position, the cooling air by the flow of the arrow C can be efficiently supplied to the hybrid radiator 22 without being obstructed by the pressure pump.

  In addition, on the vehicle rear side of the inverter 5, the cooling air flowing between the side surface 57 of the inverter 5 and the side wall 58 of the cooling room 25 facing the inverter 5 is guided by the connection surface 54 and directed toward the vehicle front side. Thus, the flow indicated by the arrow D is formed and is directed toward the hybrid radiator 22.

  Since the cooling air flowing in the cooling room 25 spreads well in the engine room 18, the degree of freedom in layout of the installation location of the hybrid radiator is increased. As a result, the degree of freedom of the arrangement relationship with the engine radiator is also increased, and measures for heat balance in the engine room 18 are facilitated.

  Furthermore, in this embodiment, although the cable harnesses 41-44 are connected to the inclined connection surfaces 54-56, in the cable harnesses 41 and 42 extended toward the vehicle rear side, immediately from the connection location of the connection surface 54. It can be routed toward the rear side of the vehicle. Therefore, it goes straight toward the hybrid radiator 22, and in order to avoid interference with the hybrid radiator 22, there is no need to bend the vehicle rearward with a small bending radius immediately before that, reducing the stress on the cable harnesses 41 and 42. In addition, since a wide space is generated in the attaching / detaching direction, maintainability is also good.

  The same effect can be obtained by the cable harnesses 43 and 44 connected to the connection surface 55 and extending toward the front side of the vehicle. In particular, since the cable harness 44 is connected to the connection surfaces 55 and 56 that are inclined so as to expand to each other, the bending radius can be increased and the stress can be reduced.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the connection surface 54 on the vehicle rear side of the inverter 5 is inclined in the opposite direction to the connection surface 55, but may be inclined so as to be continuous with the connection surface 55. In such a case, the cable harnesses 41 and 42 connected to the connection surface 54 are also routed toward the vehicle front side. Further, depending on the wiring state of the cable harnesses 41 and 42, it is possible to incline only the connection surface 55.

In the above embodiment, the connection surfaces 54 to 56 are inclined in both the terminal case 31 and the terminal box 32. However, even when one of the connection surfaces 54 to 56 is inclined, the present invention is included in the present invention. Depending on the situation, it may be triangular.
In addition, the inclination angle of the facing surface exemplified as the connection surface is not limited to 10 ° in the above embodiment, and can be appropriately set in consideration of the wiring state of the cable harness, the layout of other components, and the like. .
In the present embodiment, the capacitor is described, but a capacitor such as a lithium ion battery or a nickel metal hydride battery may be used.

  The present invention can be used not only for a construction machine other than a hybrid excavator but also for a hybrid type work machine such as a civil engineering machine, an agricultural machine, a traveling vehicle, and a transport vehicle.

  DESCRIPTION OF SYMBOLS 1 ... Hybrid hydraulic excavator (work machine), 3 ... Generator motor, 5 ... Inverter, 6 ... Capacitor (capacitor), 7 ... Swing electric motor (electric motor), 22 ... Hybrid radiator (radiator), 26 ... Electric control unit 31 ... Terminal case, 32 ... Terminal box, 33 ... Recess, 41-44 ... Cable harness (cable), 54-56 ... Connection surface (opposing surface).

Claims (5)

An electric control unit disposed in the inflow path of the cooling air;
A work machine comprising a radiator cooled by the cooling air,
The electric control unit controls a power storage unit that charges power generated by a generator motor, charging of the power to the power storage unit, and output of the charged power from the storage unit to the electric motor, and on the power storage unit. With a mounted inverter,
On the battery, a terminal box to which a cable for power transmission with the inverter is connected is provided,
On the inverter is provided a terminal case to which the cable, a cable for power transmission from the generator motor, and a cable for power transmission to the electric motor are connected,
Between the terminal case of the inverter and the terminal box of the capacitor, a recess is provided through which the cooling air passes toward the radiator,
In at least one of the terminal case and said terminal box, the opposing surface facing the radiator, the working machine, characterized in that it is inclined with respect to the flow direction of the cooling air passing through the recess. The work machine according to claim 1,
In both the terminal case and the terminal box, the facing surface that faces the radiator is inclined with respect to the flow direction of the cooling air that passes through the recess, and each of the inclined facing surfaces has the recess. A work machine characterized in that the work machine is widened to the radiator side. In the work machine according to claim 1 or 2,
The working machine characterized in that the opposing surfaces are such that their boundary portions protrude toward the radiator. An electric control unit disposed in an inflow path of cooling air to a radiator mounted on a work machine,
The electrical control unit controls a power storage unit that charges power generated by a generator motor, charging of the power to the power storage unit, and output of the charged power from the power storage unit to the electric motor. And an inverter mounted on the
On the battery, a terminal box to which a cable for power transmission with the inverter is connected is provided,
On the inverter is provided a terminal case to which the cable, a cable for power transmission from the generator motor, and a cable for power transmission to the electric motor are connected,
Between the terminal case of the inverter and the terminal box of the capacitor, a recess is provided through which the cooling air passes toward the radiator,
In at least one of the terminal case and the terminal box, an opposing surface facing the radiator is inclined with respect to a flow direction of the cooling air passing through the recess. The electric power generated by the generator motor is disposed in the inflow path of the cooling air to the radiator mounted on the work machine, and is placed on a capacitor that charges the electric power generated by the generator motor. An inverter that controls charging to a capacitor and output of the charged power from the capacitor to an electric motor,
Provided is a terminal case to which a cable for power transmission to and from the capacitor, a cable for power transmission from the generator motor, and a cable for power transmission to the electric motor are connected,
The inverter facing the radiator of the terminal case is inclined with respect to the flow direction of the cooling air passing between the terminal box and the terminal box provided on the capacitor.

Images