Drive transmission devices and construction machinery

Abstract

To suppress energy loss due to transmission from a drive source, and to efficiently and stably perform running motions such as straight running, turning, pivoting, spin turning, etc., at the same time as turning motions, and to prevent an electric shock by stabilizing running operation without water immersion of an electric motor.SOLUTION: A drive transmission device comprises a driving source that generates power and is provided in a revolving body 103 that revolves with respect to a lower carrier 106 that supports a traveling body 101 of a construction machine, and a transmission mechanism that mechanically transmits the power of the driving source to at least one of two drive wheels 105a provided on both sides of the lower carrier 106 in the vehicle width direction of the construction machine.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a drive transmission device and a construction machine. [Background Art]

[0002] For example, a construction machine such as a hydraulic excavator includes a self-propelled traveling body and a revolving body rotatably provided on the traveling body. The revolving body is provided with an operator cab where an operator rides. The revolving body is also provided with an acting portion having one end rotatably (oscillatingly) connected thereto. Examples of the acting portion include a boom, an arm having one end rotatably connected to the other end of the boom opposite to the revolving body, and a bucket rotatably connected to the other end of the arm opposite to the boom.

[0003] Further, in the above-described construction machines such as excavators, a drive transmission device for the connecting portion between the revolving body and the traveling body is often configured by combining a bevel pinion, a bevel gear, a clutch, and the like (see, for example, Patent Document 1). Patent Document 1 describes a mechanism that targets straight traveling and transmits power to a lower traveling mechanism via gears. For such a connecting portion between the revolving body and the traveling body, for example, a fluid force transmission structure using a swivel joint is employed. [Prior Art Literature] [Patent Literature]

[0004] [Patent Document 1] Japanese Patent Publication No. 3-008986 [Summary of the Invention] [Problem to be Solved by the Invention]

[0005] Here, the drive transmission device described in the aforementioned Patent Document 1 cannot simultaneously drive a traveling operation and a revolving operation. In the case of a construction machine such as an excavator, there has been a demand for being able to perform not only straight traveling but also curved traveling, pivot turn, spin turn and other traveling operations efficiently and stably while revolving during traveling. Furthermore, in the transmission of fluid power, energy losses due to piping and other factors are significant, and in recent years, electrification has been desired from the perspective of simplifying the structure of construction machinery. However, in the case of electric power transmission, there were issues with electric motors being submerged in water and the risk of electric shock for machinery such as excavators that travel through wetlands.

[0006] The present invention provides a drive transmission device and construction machinery that suppress energy loss due to transmission from the drive source and enable efficient and stable operation of driving movements such as straight-line movement, turning, pivoting, and spin turns simultaneously with turning movements. Another objective of the present invention is to provide a drive transmission device and construction machinery that prevent water ingress into the electric motor, stabilize the driving operation, and prevent electric shock. [Means for solving the problem]

[0007] A drive transmission device according to one aspect of the present invention is a lower carrier supporting the running section of a construction machine. Mounted on top of A drive source that generates power is provided on the rotating body, It is housed within the aforementioned lower carrier, The lower carrier comprises a transmission mechanism that mechanically transmits power from the drive source to at least one of the two drive wheels provided on both sides of the construction machine in the vehicle width direction. The drive source comprises a drive motor and a directional control drive motor provided on the slewing body, and the transmission mechanism comprises a differential that transmits power from the drive motor and a speed change unit that transmits power from the directional control drive motor and causes a rotational difference between one of the two drive wheels and the other drive wheel. .

[0008] With this configuration, the power generated by the drive source can be mechanically transmitted to at least one of the two drive wheels via the transmission mechanism. This suppresses the large energy loss associated with transmission from the drive source, such as with fluid or electrical transmission mechanisms, and enables stable driving. Furthermore, in this case, since the drive source that transmits power to the drive wheels via the transmission mechanism is provided on the slewing body, the power from the drive source can be transmitted to the drive wheels simultaneously with the slewing body's rotation. As a result, the driving motion of the running section can efficiently and stably perform not only straight-line movement but also cornering, pivoting, spin turns, and other driving motions simultaneously with the turning motion. Furthermore, in this embodiment, the drive source is located on a slewing body mounted on top of the lower carrier, rather than on the lower carrier which is susceptible to water damage in wet ground or wetlands. This prevents water from entering the electric motor, stabilizing the driving operation and preventing electric shock. In particular, this drive transmission device can be effectively applied to construction machinery that is frequently used in wetlands.

[0010] In the above configuration, it is desirable that the gear shifting unit has a bevel gear that transmits power from the directional control drive motor to one of the drive wheels.

[0011] In the above configuration, the transmission mechanism comprises a drive shaft that receives power from the drive motor and a directional control shaft that receives power from the directional control drive motor, wherein the drive shaft is provided coaxially with the pivot axis of the pivoting body, and the directional control shaft preferably revolves around the drive shaft.

[0012] In the above configuration, it is preferable that the transmission mechanism comprises a first spur gear connected to the direction control shaft, a second spur gear that meshes with the first spur gear and passes through the drive shaft, a first bevel gear connected to the second spur gear, and a second bevel gear that meshes with the first bevel gear and is connected to the axle of one of the drive wheels.

[0013] A drive transmission device according to another aspect of the present invention is a lower carrier supporting the running section of a construction machine. Mounted on top of A drive source that generates power is provided on the rotating body, It is housed within the aforementioned lower carrier,The lower carrier comprises a transmission mechanism that mechanically transmits power from the drive source to at least one of the two drive wheels provided on both sides of the construction machine in the vehicle width direction, the drive source comprises a drive motor and a directional control drive motor provided on the slewing body, the transmission mechanism comprises a differential that transmits power from the drive motor, and a gearbox that transmits power from the directional control drive motor and creates a rotational difference between one of the two drive wheels and the other drive wheel, the gearbox has a bevel gear that transmits power from the directional control drive motor to the one of the drive wheels, and The transmission mechanism comprises a drive shaft that receives power from the drive motor and a directional control shaft that receives power from the directional control drive motor, wherein the drive shaft is provided coaxially with the pivot axis of the pivoting body, and the directional control shaft revolves around the drive shaft. The transmission mechanism comprises a first spur gear connected to the directional control shaft, a second spur gear that meshes with the first spur gear and passes through the drive shaft, a first bevel gear connected to the second spur gear, and a second bevel gear that meshes with the first bevel gear and is connected to the axle of one of the drive wheels.

[0014] With this configuration, the vehicle is equipped with a differential and a gearbox that mechanically transmits power generated by the drive motor and directional control motor to at least one of the two drive wheels via a transmission mechanism. This suppresses the large energy loss caused by transmission from the drive motor and directional control motor, such as with fluid or electrical transmission mechanisms, and enables stable driving. In this case, the slewing body is provided with a drive motor and directional control motor that transmit power to the drive wheels via a transmission mechanism, allowing the power from the drive motor and directional control motor to be transmitted to the drive wheels simultaneously with the turning of the slewing body. Moreover, the gearbox can create a rotational difference between one axle and the other, so the vehicle can efficiently perform not only straight-line driving but also cornering, pivoting, spin turns, and other driving maneuvers simultaneously with the turning operation, and with stable operation. Furthermore, in this configuration, the drive source is located on the slewing body mounted on top of the lower carrier, rather than on the lower carrier which is susceptible to water damage in wet ground or wetlands. This prevents water from entering the electric motor, ensuring stable operation and preventing electric shock. In particular, this drive transmission device can be effectively applied to construction machinery that is frequently used in wetlands. Furthermore, the directional control shaft of the transmission unit and the drive shaft for the differential are provided separately, and the bevel gear of the directional control shaft of the transmission unit can be used to increase or decrease the rotational speed of one of the drive wheels to change the gear. In this case, the first transmission shaft 31 and the second transmission shaft 41 do not interfere with each other when turning, and driving and turning operations can be performed simultaneously. Furthermore, in this case, the power of the directional control drive motor is transmitted in the order of the first spur gear, second spur gear, first bevel gear, second bevel gear, and axle, and power can be transmitted to the drive wheels connected to the axle. Therefore, the directional control drive motor and directional control shaft can be installed at a position away from the pivot axis.

[0015] A construction machine according to another aspect of the present invention comprises a lower carrier that supports a running section, and the lower carrier Mounted on top of A rotating body, two drive wheels provided on both sides of the lower carrier in the vehicle width direction, and a drive source provided on the rotating body to generate power, It is housed within the aforementioned lower carrier, The drive transmission device includes a transmission mechanism that mechanically transmits power from the drive source to at least one of the two drive wheels, The drive source comprises a drive motor and a directional control drive motor provided on the slewing body, and the transmission mechanism comprises a differential that transmits power from the drive motor and a speed change unit that transmits power from the directional control drive motor and causes a rotational difference between one of the two drive wheels and the other drive wheel. .

[0016] With this configuration, the power generated by the drive source can be mechanically transmitted to at least one of the two drive wheels via the transmission mechanism. This suppresses the large energy loss caused by transmission from the drive source, such as with fluid or electrical transmission mechanisms, and enables stable driving. Furthermore, in this case, since the drive source that transmits power to the drive wheels via the transmission mechanism is provided on the slewing body, the power from the drive source can be transmitted to the drive wheels simultaneously with the slewing body's rotation. As a result, the driving motion of the running section can efficiently and stably perform not only straight-line movement but also cornering, pivoting, spin turns, and other driving motions simultaneously with the turning motion. Furthermore, in this embodiment, the drive source is provided on a slewing body mounted on top of the lower carrier, rather than on the lower carrier which is susceptible to water damage in wet ground or swamps. This prevents water from entering the electric motor, stabilizing the driving operation and preventing electric shock.

[0017] Another aspect of the present invention relates to a drive transmission device comprising a drive source that generates power and is provided on a second drive unit that is mounted on the upper part of a first drive unit and rotates, and two drives provided on the first drive unit. ring The two drives are housed within the first drive unit. ring at least one of the drives ring The vehicle comprises a transmission mechanism for transmitting power from the drive source, the drive source having a drive motor and a directional control drive motor provided on the second drive body, and the transmission mechanism comprising a differential to which power from the drive motor is transmitted, and a speed change unit to which power from the directional control drive motor is transmitted, causing a rotational difference between one of the two drive wheels and the other drive wheel.

[0018] With this configuration, the power generated by the drive source can be mechanically transmitted to at least one of the two drive shafts via the transmission mechanism, so that an increase in energy loss caused by transmission from the drive source, which occurs in fluid power or electric transmission mechanisms, can be suppressed, and stable traveling operation can be performed. Further, in this case, since a transmission mechanism for transmitting the power of the drive source to the drive shaft is provided in the second driving body via the transmission mechanism, the power of the drive source can be transmitted to the drive shaft simultaneously with the turning of the second driving body. Accordingly, when the first driving body performs a traveling operation, not only straight traveling but also traveling operations such as curved traveling, pivot turning, and spin turning can be efficiently performed simultaneously with a turning operation as the traveling operation, and can be performed with stable operation. Furthermore, in this aspect, when the first driving body is a traveling body, the drive source is provided not on the first driving body, which is easily affected by water on wet ground, wetlands, or the like, but on the second driving body mounted on top of the first driving body. Accordingly, the electric motor does not flood, traveling operation is stabilized, and electric shock can be prevented. Effects of the Invention

[0019] The drive transmission device and construction machine described above can suppress energy loss caused by transmission from the drive source, and can perform traveling operations such as straight traveling, curved traveling, pivot turning, and spin turning efficiently and stably simultaneously with a turning operation. Furthermore, the drive transmission device and construction machine described above prevent the electric motor from being flooded, stabilize traveling operation, and can prevent electric shock. Brief Description of the Drawings

[0020] [Figure 1] A schematic configuration view of an excavator according to an embodiment of the present invention as seen from a side. [Figure 2] A schematic configuration diagram showing details of a connecting portion between a revolving portion and a traveling portion in an embodiment of the present invention. [Figure 3] A top plan view of a lower carrier according to another embodiment of the present invention. Mode for Carrying Out the Invention

[0021] Next, embodiments of the present invention will be described with reference to the drawings.

[0022] <Shovel> Figure 1 is a schematic side view of a shovel 100 according to an embodiment of the construction machinery of the present invention. In the following description, the front of the shovel 100, towards which an operator (not shown) is facing, will be simply referred to as the front. The direction opposite to the front in the horizontal direction will be referred to as the rear. The vertical direction when the shovel 100 is positioned on the road surface will be simply referred to as the vertical direction. The direction perpendicular to the front-rear direction and the vertical direction will be referred to as the vehicle width direction. Figure 1 shows the shovel 100 as viewed from the vehicle width direction.

[0023] As shown in Figure 1, the shovel 100 comprises a self-propelled vehicle 101, a slewing body 103 (second drive body) mounted on the upper part of the vehicle 101 via a slewing mechanism 10 that slewing relative to the vehicle 101, and an operating part 104 mounted on the slewing body 103. The vehicle 101 and the slewing mechanism 10 are driven by an electric motor with a reduction gear (hereinafter referred to as drive motor 2) as shown in Figure 2. As shown in Figure 2, the vehicle 101 comprises, for example, two crawlers 105 (first crawler 105A, second crawler 105B) arranged in the vehicle width direction, and a lower carrier 106 (first drive body) that supports this pair of crawlers 105. However, it is not limited to this, and wheels or the like may be used instead of crawlers 105. The crawler 105 is equipped with a drive wheel 105a, and the rotation of the drive wheel 105a rotates the entire endless crawler 105.

[0024] As shown in Figure 1, the working unit 104 comprises a boom 108 and an arm 109 that are long in the front-rear direction, and a bucket 110. The boom 108, arm 109, and bucket 110 are each rotatably connected via a drive transmission device (not shown).

[0025] Figure 2 is a schematic diagram showing the details of the drive transmission device 1 provided on the traveling body 101 and the slewing body 103. The lower carrier 106 of the traveling body 101 is equipped with a slewing mechanism 10 and the drive transmission device 1. Figure 3 is a plan view showing another configuration as seen from above along line AA in Figure 2. In Figure 2, when viewed from above, the outer diameter of the slewing gear 11 is such that the outer circumference of the slewing gear 11 overlaps the upper part of the second spur gear 43, and the outer diameter of the first spur gear 42 is such that the outer circumference of the first spur gear 42 overlaps the lower part of the ring gear 12. On the other hand, as shown in Figure 3, the diameters of the slewing gear 11 and the first spur gear 42 may be smaller than those of the slewing gear 11 and the first spur gear 42 shown in Figure 2. The drive transmission device 1 comprises components arranged within the area enclosed by the outer dashed line shown in Figure 2.

[0026] As shown in Figure 2, the drive motor 2 consists of a drive motor 2A (drive source), a directional control drive motor 2B (drive source), and a slewing drive motor 2C. The slewing body 103 is equipped with three drive motors 2 (2A, 2B, 2C) that generate power. The drive transmission device 1 transmits the rotational force of two of the drive motors 2A and 2B (drive sources according to the claim) to at least one of the two crawlers 105. The drive transmission device 1 transmits the rotational speed of the other drive motor 2C to the slewing body as a slewing force.

[0027] The drive motor 2A is the drive source that provides rotational force to the drive wheels 105a of the crawler 105 to propel the vehicle 101. The directional control drive motor 2B is the drive source that transmits power to create a rotational difference between the drive wheels 105a of the crawlers 105A and 105B, which are provided on both sides in the vehicle width direction. The slewing drive motor 2C is the drive source that slewing the slewing body 103 relative to the vehicle 101. The directional control drive motor 2B and the slewing drive motor 2C are provided radially outward from the first rotation axis C1 of the drive motor 2A, in positions where they do not interfere with each other.

[0028] Each of the drive motors 2A, 2B, and 2C is a so-called electric motor that is driven by power supplied from, for example, an external power source (battery) provided on the rotating body 103. As motor 2, various motors that are driven by power supply can be used, such as so-called brushed motors and brushless motors.

[0029] The drive motors 2A, 2B, and 2C are positioned so that the shaft axes of the motor shafts 21A, 21B, and 21C, which rotate around their respective centers of rotation, are parallel to the pivot axis O of the pivot body 103. The first rotation axis C1 of the motor shaft 21A of the drive motor 2A (the first rotation axis C1 of the first transmission shaft 31), which will be described later, coincides with the pivot axis O.

[0030] <Swivel mechanism> As shown in Figures 2 and 3, the slewing mechanism 10 includes a slewing gear 11 connected to the motor shaft 21C of the slewing drive motor 2C, and a ring gear 12 provided on the upper part of the traveling body 101 and coaxial with the slewing center axis O, with which the slewing gear 11 meshes. The ring gear 12 has internal teeth 12a. On the inner circumference side of the ring gear 12 are the slewing gear 11, the first transmission shaft 31 (drive shaft) connected to the drive motor 2A, and the second transmission shaft 41 connected to the directional control drive motor 2B. When the slewing drive motor 2C is driven, the slewing gear 11 rotates while meshing with the internal teeth 12a of the ring gear 12, and depending on the direction of rotation of the slewing gear 11, the slewing gear 11 revolves in either the forward or reverse direction along the internal teeth 12a provided on the circumferential direction of the ring gear 12. As a result, the slewing body 103 rotates on the traveling body 101.

[0031] <Drive transmission system> Next, the drive transmission device 1 will be described. As shown in Figure 2, the drive transmission device 1 is positioned on the second rotation axis (an example of the rotation axis in the claim) C2 of a pair of crawlers 105A and 105B. The first crawler 105A and the second crawler 105B are positioned on either side of the drive transmission device 1 on the second rotation axis C2. As these crawlers 105A and 105B are supported by the drive transmission device 1, the rotational driving force of the drive transmission device 1 is transmitted to the crawlers 105A and 105B. As a result, the drive wheels 105a of the pair of crawlers 105A and 105B rotate around the second rotation axis C2 relative to the lower carrier 106.

[0032] The drive transmission device 1 comprises a differential 3 and a transmission device 4 (speed control unit) housed within the lower carrier 106. The differential 3 is connected to the drive motor 2A and transmits power from the drive motor 2A. The transmission device 4 is connected to the directional control drive motor 2B and transmits power from the directional control drive motor 2B. The first motor shaft 21A of the drive motor 2A and the second motor shaft 21B of the directional control drive motor 2B are parallel.

[0033] <Differential device> As shown in Figure 2, the differential gear 3 is connected via a first transmission shaft 31 connected to the first motor shaft 21A. The differential gear 3 is provided at the end of the first transmission shaft 31 opposite to the drive motor 2A and includes a first bevel gear 32 that rotates around a first rotation axis C1, a second bevel gear 33 that meshes with the first bevel gear 32 and rotates around a second rotation axis C2, a differential case 34 fixed to the second bevel gear 33, a pair of pinion gears 35A and 35B that are rotatably supported and protrude within the differential case 34, and a pair of side gears 36A and 36B (first side gear 36A, second side gear 36B) that mesh with the pinion gears 35A and 35B.

[0034] A circular opening (not shown) is formed in the radial center of the second bevel gear 33, through which the differential case 34 passes. In Figure 2, a portion of the second bevel gear 33 is omitted for clarity. The differential case 34 is fixed in place with its passage through the opening of the second bevel gear 33.

[0035] The differential case 34 is formed in a cylindrical frame shape and has two sides 34a and 34b (first side 34a and second side 34b) that are positioned opposite each other in the axial direction of the second rotation axis C2, and two sides 34c and 34d (third side 34c and fourth side 34d) that are positioned opposite each other in a direction perpendicular to the plane direction of these sides 34a and 34b. Of the four sides 34a to 34d, the third side 34c and the fourth side 34d are fixed to the second bevel gear 33, respectively.

[0036] Furthermore, pinion gears 35A and 35B are provided on the third side surface 34c and the fourth side surface 34d. The pinion gears 35A and 35B are rotatably supported on each side surface 34c and 34d with respect to a third rotation axis C3 (an axis parallel to the first rotation axis C1 and coaxial with the first transmission shaft 31) which is perpendicular to the axial direction, and rotate together with the differential case 34 around the second rotation axis C2.

[0037] The pair of side gears 36A and 36B are positioned on either side of the pinion gears 35A and 35B. Specifically, of the pair of side gears 36A and 36B, the first side gear 36A is positioned coaxially with the second rotation axis C2 inside the first side surface 34a of the differential case 34. Of the pair of side gears 36A and 36B, the second side gear 36B is positioned coaxially with the second rotation axis C2 inside the second side surface 34b of the differential case 34.

[0038] One end of the first operating output shaft 37A (axle) is provided on the end face 36a of the first side 34a of the first side gear 36A. The first operating output shaft 37A is arranged coaxially with the second rotation axis C2. The other end of the first operating output shaft 37A protrudes through a through hole 34e formed in the first side 34a. In other words, the first side gear 36A is rotatably supported on the first side 34a of the differential case 34. The other end of the first operating output shaft 37A is connected to the drive wheel 105a of the first crawler 105A. That is, the rotational force of the first operating output shaft 37A is transmitted to the drive wheel 105a of the first crawler 105A, giving rotational force to the first crawler 105A.

[0039] The second side gear 36B has one end of the second operating output shaft 37B (axle) provided on the end face 36b on the second side surface 34b. The second operating output shaft 37B is arranged coaxially with the second rotation axis C2. The other end of the second operating output shaft 37B protrudes through a through hole 34f formed in the second side surface 34b and a fourth bevel gear 45, which will be described later. In other words, the second side gear 36B is rotatably supported on the second side surface 34b of the differential case 34. The other end of the second operating output shaft 37B is connected to the drive wheel 105a of the second crawler 105B. That is, the rotational force of the second operating output shaft 37B is transmitted to the drive wheel 105a of the second crawler 105B, giving rotational force to the second crawler 105B.

[0040] <Transmission> Next, I will explain the transmission 4. As shown in Figure 2, the transmission 4 has the function of creating a rotational difference between the first operating output shaft 37A and the second operating output shaft 37B. The transmission 4 is separate from the first transmission shaft 31 of the differential 3 and is connected via a second transmission shaft 41 (directional control shaft) which is connected to the directional control drive motor 2B. Specifically, the transmission 4 comprises a first spur gear 42 provided on the end of the second transmission shaft 41 opposite to the directional control drive motor 2B, a second spur gear 43 (spur gear in the claim) which is a spur gear that meshes with the first spur gear 42 and rotates around a first rotation axis C1, a third bevel gear 44 which is fixed coaxially to the second spur gear 43 and rotates around the first rotation axis C1, and a fourth bevel gear 45 which meshes with the third bevel gear 44 and is fixed coaxially to the second operating output shaft 37B.

[0041] As shown in Figure 3, the second transmission shaft 41 and the first spur gear 42 are arranged radially outward relative to the first transmission shaft 31. The first spur gear 42 is a spur gear. The second spur gear 43 rotates in mesh with the first spur gear 42, and as the slewing body 103 rotates relative to the traveling body 101, it revolves around the outside of the first transmission shaft 31 (i.e., around the first rotation axis C1) together with the directional control drive motor 2B and the second transmission shaft 41. A through hole 43a is formed in the radial center of the second spur gear 43 for the first transmission shaft 31 to pass through. A cylindrical connecting shaft 46 is connected to the radial center of the end face 43b of the second spur gear 43 on the differential case 34 side, extending in a direction perpendicular to the end face 43b. The first transmission shaft 31 passes through the connecting shaft 46. A third bevel gear 44 is provided at the end of the connecting shaft 46 opposite to the second spur gear 43, and rotates around the first rotation axis C1.

[0042] A through hole 44a is formed in the radial center of the third bevel gear 44, through which the first transmission shaft 31 passes. In other words, the third bevel gear 44 is mounted coaxially with the first bevel gear 32 and rotates around the first rotation axis C1. The fourth bevel gear 45 rotates around the second rotation axis C2. A through hole 45a is formed in the radial center of the fourth bevel gear 45, through which the second operating output shaft 37B passes. The second operating output shaft 37B is fixed in place through the through hole 45a of the fourth bevel gear 45.

[0043] In the transmission 4, when the shovel 100 is traveling, the rotation speed and direction of the directional control drive motor 2B are matched with the rotation speed and direction of the drive drive motor 2A, so that the rotation of the first operating output shaft 37A and the second operating output shaft 37B are also matched, and the traveling body 101 moves in a straight line. Then, by changing the rotation speed and direction of the directional control drive motor 2B from that of the drive drive motor 2A, a rotational difference is created between the first operating output shaft 37A and the second operating output shaft 37B, and the traveling body 101 can perform traveling actions such as turning, pivoting, and spin turns.

[0044] <Operation of the drive transmission system> Next, the operation of the drive transmission device 1 will be explained. As shown in Figure 2, when the drive motor 2A provided on the slewing body 103 is driven, the rotation of the motor shaft 21A of the drive motor 2A is transmitted to the first bevel gear 32 of the drive transmission device 1 via the first transmission shaft 31. Then, the second bevel gear 33 that meshes with the first bevel gear 32 is rotated. Furthermore, the differential case 34 fixed to the second bevel gear 33 is rotated. As a result, the pinion gears 35A and 35B are rotated around the second rotation axis C2. This causes the pair of side gears 36A and 36B that mesh with the pinion gears 35A and 35B to rotate.

[0045] Of the pair of side gears 36A and 36B, the rotation of the first side gear 36A is transmitted to the drive wheel 105a of the first crawler 105A via the first operating output shaft 37A. Of the pair of side gears 36A and 36B, the rotation of the second side gear 36B is transmitted to the second crawler 105B via the second operating output shaft 37B. At this time, the fourth bevel gear 45 of the transmission 4 rotates together with the second operating output shaft 37B. The rotational speed of the second operating output shaft 37B is controlled by the directional control drive motor 2B via the transmission 4. The operation of the transmission 4 during directional control will be described below.

[0046] The transmission 4 rotates the second operating output shaft 37B at an appropriate rotational speed by the drive of the directional control drive motor 2B. In other words, the transmission 4 rotates the first operating output shaft 37A and the second operating output shaft 37B at the same rotational speed, or at a difference in rotational speed.

[0047] When the shovel 100 is to travel in a straight line, the rotational speed and direction of the directional drive motor 2B are controlled to match the rotational speed and direction of the drive motor 2A. In other words, when traveling in a straight line, the first operating output shaft 37A and the second operating output shaft 37B rotate at the same rotational speed. Therefore, the fourth bevel gear 45, which is fixed to the second operating output shaft 37B of the transmission 4 and rotates around the second rotation axis C2, the third bevel gear 44, which meshes with the fourth bevel gear 45 and rotates around the first rotation axis C1, the second spur gear 43, which rotates integrally with the third bevel gear 44, the first spur gear 42, which meshes with the second spur gear 43, and the directional drive motor 2B, which connects the first spur gear 42 via the second transmission shaft 41, are controlled to rotate at the same rotational speed as the second operating output shaft 37B. As a result, the traveling body 101 of the shovel 100 travels in a straight line.

[0048] When the shovel 100 performs cornering, pivoting, spinning, or other driving actions, the rotational speed and direction of the directional control drive motor 2B are controlled to differ from those of the drive drive motor 2A. In other words, when cornering or performing other such actions, the directional control drive motor 2B is controlled so that a rotational difference is created between the first operating output shaft 37A and the second operating output shaft 37B.

[0049] For example, when moving the vehicle 101 in one direction (first direction X1 shown in Figure 2), the left and right crawlers 105A and 105B are rotated by the drive motor 2A, and the first crawler 105A is rotated faster than the second crawler 105B. Specifically, by controlling the rotation speed of the second operating output shaft 37B, that is, the rotation speeds of the third bevel gear 44 and the fourth bevel gear 45, to be smaller than that of the first operating output shaft 37A, the vehicle 101 moves in the first direction X1.

[0050] Furthermore, when moving the vehicle 101 in a curved direction (second direction X2 shown in Figure 2), the drive motor 2A rotates the left and right crawlers 105A and 105B, and the second crawler 105B is rotated faster than the first crawler 105A. Specifically, by controlling the rotation speed of the second operating output shaft 37B, that is, the rotation speeds of the third bevel gear 44 and the fourth bevel gear 45, to be greater than that of the first operating output shaft 37A, the vehicle 101 curves in the second direction X2.

[0051] Next, when the turning body 103 turns while the traveling body 101 is traveling, the traveling speed of the drive motor 2A and the rotational speed of the turning drive motor 2C due to turning are detected by a control unit (not shown), and the rotational speed of the directional control drive motor 2B is controlled according to these detected values. For example, when the traveling body 101 turns while traveling in a straight line, the directional control drive motor 2B is controlled so that the rotational speed of the second transmission shaft 41 matches the rotational speed of the first transmission shaft 31 by increasing or decreasing the rotational speed due to turning relative to the rotational speed during travel. Furthermore, when the traveling body 101 turns while traveling in a curved direction (including pivot and spin turn), the directional control drive motor 2B is controlled so that the rotational speed of the second transmission shaft 41 differs from that of the drive drive motor 2A, by increasing or decreasing the rotational speed due to turning relative to the rotational speed during travel, so that a rotational difference is created between the pair of operating output shafts 37A and 37B.

[0052] As described above, in the embodiment shown in Figure 2, the drive transmission device 1 includes a drive motor 2A (drive source) and a directional control drive motor 2B (drive source) that are provided on a slewing body 103 that pivots relative to the lower carrier 106 that supports the traveling body 101 of the shovel 100 and generate power, and a transmission mechanism that mechanically transmits the power of the drive motor 2A and the directional control drive motor 2B to at least one of the two crawlers 105 (drive wheels) provided on both sides of the vehicle width direction of the shovel 100 on the lower carrier 106. Therefore, since the power generated by the drive motor 2A and the directional control drive motor 2B can be mechanically transmitted to at least one of the two crawlers 105 via the transmission mechanism, energy loss due to transmission from a drive source such as hydrodynamic or electric transmission mechanisms can be suppressed, and stable driving operation can be performed. Furthermore, in this case, the slewing body 103 is equipped with drive sources for a drive motor 2A and a directional control drive motor 2B that transmit power to the drive wheels 105a of the crawler 105 via a transmission mechanism. This allows the power from these drive sources to be transmitted to the drive wheels 105a simultaneously with the slewing of the slewing body 103. As a result, the traveling body 101 can efficiently perform not only straight-line travel but also cornering, pivoting, spin turns, and other traveling movements simultaneously with the slewing movement, and these movements can be performed with stability. Moreover, in this embodiment, the drive source is provided in the slewing body 103 mounted on top of the lower carrier 106, rather than in the lower carrier 106, which is susceptible to water damage in wet ground or wetlands. This prevents water from entering the electric motor, stabilizing the travel operation and preventing electric shock. In particular, the drive transmission device 1 of this embodiment can be effectively applied to construction machinery that is often used in wetlands.

[0053] The drive source includes a drive motor 2A and a directional control drive motor 2B provided on the slewing body 103. The transmission mechanism includes a differential 3 to which the power of the drive motor 2A is transmitted, and a transmission 4 to which the power of the directional control drive motor 2B is transmitted, causing a rotational difference between one of the two drive wheels 105a and the other drive wheel 105a. With this configuration, the differential 3 and transmission 4 mechanically transmit the power generated by the drive motor 2A and the directional control drive motor 2B to at least one of the two drive wheels 105a via the transmission mechanism, thereby suppressing large energy losses due to transmission from the drive motor 2A and the directional control drive motor 2B, unlike fluid or electrical transmission mechanisms, and enabling stable driving operation. In this configuration, the slewing body 103 is equipped with a drive motor 2A and a directional control drive motor 2B that transmit power to the drive wheels 105a via a transmission mechanism, allowing the power from the drive motor 2A and the directional control drive motor 2B to be transmitted to the drive wheels 105a simultaneously with the rotation of the slewing body 103. Moreover, the transmission 4 can create a rotational difference between the first operating output shaft 37A and the second operating output shaft 37B, so that the running motion of the running section can efficiently perform not only straight-line movement but also turning, pivoting, spin turns, and other running motions simultaneously with the turning motion, and with stable operation. Furthermore, in this configuration, the drive motor 2A and the directional control drive motor 2B are provided on the slewing body 103 mounted on top of the lower carrier 106, rather than on the lower carrier 106 which is susceptible to water damage in wet ground or swamps, thus preventing water ingress into the motors, stabilizing the running motion, and preventing electric shock. In particular, the drive transmission device 1 of this embodiment can be effectively applied to construction machinery such as the shovel 100, which is often used in wetlands.

[0054] The transmission 4 has bevel gears 44 and 45 that transmit power from the directional control drive motor 2B to one of the drive wheels 105a. The transmission mechanism includes a first transmission shaft 31 that receives power from the drive motor 2A and a second transmission shaft 41 that receives power from the directional control drive motor 2B. The first transmission shaft 31 is mounted coaxially with the pivot axis O of the slewing body 103, and the second transmission shaft 41 revolves around the outside of the first transmission shaft 31. As a result, the second transmission shaft 41 of the transmission 4 and the first transmission shaft 31 for travel of the differential 3 are provided separately, and the rotational speed of one of the drive wheels 105a can be increased or decreased by using the bevel gears 44 and 45 of the second transmission shaft 41 of the transmission 4 to change the speed. In this case, the first transmission shaft 31 and the second transmission shaft 41 do not interfere with each other when turning, and travel and turning operations can be performed simultaneously.

[0055] The transmission mechanism includes a first spur gear 42 connected to a second transmission shaft 41, a second spur gear 43 that meshes with the first spur gear 42 and passes through the first transmission shaft 31, a third bevel gear 44 (the first bevel gear according to the claim) connected to the second spur gear 43, and a fourth bevel gear 45 (the second bevel gear according to the claim) that meshes with the third bevel gear 44 and is connected to the second operating output shaft 37B of one of the drive wheels 105a. As a result, the power of the directional control drive motor 2B is transmitted in the order of the first spur gear 42, the second spur gear 43, the third bevel gear 44, the fourth bevel gear 45, and the second operating output shaft 37B, and power can be transmitted to the drive wheel 105a connected to the second operating output shaft 37B. Therefore, the directional control drive motor 2B and the second transmission shaft 41 can be installed at a position away from the pivot center axis O.

[0056] It should be noted that the present invention is not limited to the embodiments described above, and various design modifications are possible without departing from the spirit of the invention.

[0057] For example, in the above embodiment, a pair of crawlers 105 are used as the running gear driven by drive wheels 105a provided on the lower carrier 106, but the system is not limited to crawlers 105 and may also consist of wheels.

[0058] Furthermore, in this embodiment, the transmission 4, which is operated by the directional control drive motor 2B, transmits its power to only one drive wheel 105a to perform the gear change. However, the configuration may also be such that the power of the directional control drive motor 2B is transmitted to the drive wheels 105a on both sides in the vehicle width direction.

[0059] As described in the above embodiment, the transmission mechanism comprises a first spur gear 42 connected to a second transmission shaft 41, a second spur gear 43 that meshes with the first spur gear 42 and passes through the first transmission shaft 31, a third bevel gear 44 connected to the second spur gear 43, and a fourth bevel gear 45 that meshes with the third bevel gear 44 and is connected to the second operating output shaft 37B of one of the drive wheels 105a. However, the mechanism is not limited to this configuration.

[0060] Furthermore, the construction machinery equipped with the drive transmission device 1 is not limited to the shovel 100 as in the above embodiment, but can also be applied to construction machinery other than shovels.

[0061] Among the embodiments disclosed herein, those composed of multiple objects may be integrated, and conversely, those composed of a single object may be divided into multiple objects. Whether or not they are integrated, the invention can be constructed in a way that achieves its objective. [Explanation of Symbols]

[0062] 1...Drive transmission device, 2...Drive motor, 2A...Drive drive motor (drive source), 2B...Direction control drive motor (drive source), 2C...Slewing drive motor, 3...Differential (transmission mechanism), 31...First transmission shaft (drive shaft), 32...First bevel gear, 33...Second bevel gear, 34...Differential case, 37A...First operating output shaft (axle), 37B...Second operating output shaft (axle), 4...Transmission device (transmission unit, transmission mechanism), 41...Second transmission shaft (direction Control shaft), 42...First spur gear, 43...Second spur gear, 44...Third bevel gear (first bevel gear), 45...Fourth bevel gear (second bevel gear), 10...Slewing mechanism, 11...Slewing gear, 12...Ring gear, 100...Shovel (construction machine), 101...Running body (running section), 103...Slewing body (second drive unit), 105...Crawler, 105a...Drive wheel (drive shaft), 106...Lower carrier (first drive unit), C1...First rotation axis, C2...Second rotation axis, O...Slewing center axis

Claims

1. A drive source that generates power is provided on a rotating body mounted on top of the lower carrier that supports the running gear of construction machinery, A transmission mechanism housed within the lower carrier and mechanically transmitting power from the drive source to at least one of the two drive wheels provided on both sides of the lower carrier in the vehicle width direction of the construction machine, Equipped with, The drive source comprises a drive motor and a directional control drive motor provided on the rotating body. The aforementioned transmission mechanism is A differential to which the power of the aforementioned drive motor is transmitted, A drive transmission device comprising a speed change unit that transmits power from the aforementioned direction control drive motor and generates a rotational difference between one of the two drive wheels and the other drive wheel.

2. The drive transmission device according to claim 1, wherein the gear shifting section has a bevel gear that transmits power from the directional control drive motor to one of the drive wheels.

3. The aforementioned transmission mechanism is The drive shaft that receives power from the aforementioned drive motor, A directional control shaft that receives power from the aforementioned directional control drive motor, Equipped with, The drive shaft is provided coaxially with the pivot axis of the pivoting body, The drive transmission device according to claim 1 or 2, wherein the direction control shaft revolves around the outside of the drive shaft.

4. The aforementioned transmission mechanism is A first spur gear connected to the aforementioned directional control shaft, A second spur gear that meshes with the first spur gear and passes through the drive shaft, A first bevel gear connected to the second spur gear, A second bevel gear meshes with the first bevel gear and is connected to the axle of one of the drive wheels, The drive transmission device according to claim 3, comprising:

5. A drive source that generates power is provided on a rotating body mounted on top of the lower carrier that supports the running gear of construction machinery, A transmission mechanism housed within the lower carrier and mechanically transmitting power from the drive source to at least one of the two drive wheels provided on both sides of the lower carrier in the vehicle width direction of the construction machine, Equipped with, The drive source comprises a drive motor and a directional control drive motor provided on the rotating body. The aforementioned transmission mechanism is A differential to which the power of the aforementioned drive motor is transmitted, The system includes a speed control unit to which the power of the aforementioned directional control drive motor is transmitted, causing a rotational difference between one of the two drive wheels and the other drive wheel, The gear shifting unit has a bevel gear that transmits power from the directional control drive motor to one of the drive wheels. The aforementioned transmission mechanism is The drive shaft that receives power from the aforementioned drive motor, The system includes a directional control shaft that receives power from the aforementioned directional control drive motor, The drive shaft is provided coaxially with the pivot axis of the pivoting body, The aforementioned directional control shaft revolves around the outside of the drive shaft, The aforementioned transmission mechanism is A first spur gear connected to the aforementioned directional control shaft, A second spur gear that meshes with the first spur gear and passes through the drive shaft, A first bevel gear connected to the second spur gear, A drive transmission device comprising: a second bevel gear that meshes with the first bevel gear and is connected to the axle of one of the drive wheels.

6. The lower carrier that supports the running gear, A rotating body mounted on the upper part of the aforementioned lower carrier, Two drive wheels are provided on both sides of the lower carrier in the vehicle width direction, A drive source provided on the rotating body to generate power, A transmission mechanism housed within the lower carrier mechanically transmits power from the drive source to at least one of the two drive wheels, It has a drive transmission device equipped with, The drive source comprises a drive motor and a directional control drive motor provided on the rotating body. The aforementioned transmission mechanism is A differential to which the power of the aforementioned drive motor is transmitted, A construction machine comprising a speed change unit to which the power of the aforementioned directional control drive motor is transmitted, and which creates a rotational difference between one of the two drive wheels and the other drive wheel.

7. A drive source is provided on the second drive unit, which is mounted on the upper part of the first drive unit and rotates, and generates power. The first drive unit is provided with two drive wheels, A transmission mechanism housed within the first drive unit transmits power from the drive source to at least one of the two drive wheels, Equipped with, The drive source includes a drive motor and a directional control drive motor provided on the second drive unit. The aforementioned transmission mechanism is A differential to which the power of the aforementioned drive motor is transmitted, A drive transmission device comprising a speed change unit that transmits power from the aforementioned direction control drive motor and generates a rotational difference between one of the two drive wheels and the other drive wheel.

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