JP7513828B2 - Construction Machinery - Google Patents

Description

The present invention relates to construction machinery.

For example, a construction machine such as a hydraulic excavator has a self-propelled running body and a rotating body that is rotatably attached to the running body. The rotating body has an operation room in which an operator sits. The rotating body is also provided with an operating part, one end of which is connected to be freely rotatable (free to swing). Examples of the operating part include a boom, an arm one end of which is rotatably connected to the other end of the boom opposite the rotating body, and a bucket rotatably connected to the other end of the arm opposite the boom.

A hydraulic actuator with a linear motion mechanism is often provided at the connection between the rotating body and the boom, the connection between the boom and the arm, and the connection between the arm and the bucket. The hydraulic actuator has a cylinder tube and a piston rod that extends and retracts into the cylinder tube. For example, at the connection between the rotating body and the boom, the cylinder tube is rotatably attached to either the rotating body or the boom, and the tip of the piston rod is rotatably attached to the other. Hydraulic actuators are also attached to the connection between the boom and the arm, and the connection between the arm and the bucket. With this configuration, the boom, arm, and bucket are swung by making the piston rod extend and retract into the cylinder tube.

In recent years, there has been a demand for electrification in construction machinery in order to simplify its structure. For this reason, a technology has been disclosed that uses an electric cylinder with a linear motion mechanism incorporating a ball screw type reduction gear instead of a hydraulic actuator. The mounting structure of this ball screw type reduction gear to the construction machinery is similar to that of a hydraulic cylinder. That is, for example, the cylinder is rotatably mounted to either the rotating body or the boom, and the tip of the piston is rotatably mounted to the other.

JP 2003-82707 A

However, in the above-mentioned conventional technology, since it is necessary to rotatably support the cylinder or piston on the boom, etc., a rotation mechanism is also used in addition to the linear motion mechanism. That is, in order to rotatably support the cylinder or piston on the boom, etc., a shaft or a bearing for rotatably supporting the shaft is prepared as a rotation mechanism, and the cylinder or piston is rotatably connected to the boom, etc. via this rotation mechanism. In this way, there is an issue that it is difficult to simplify the structure of the construction machine because a linear motion mechanism and a rotation mechanism are used in combination.

The present invention provides a construction machine whose structure can be reliably simplified by electrifying it.

A construction machine according to one aspect of the present invention comprises a self-propelled main body, an action part attached to the main body, and a speed reduction mechanism part provided on a part of the action part for driving the part to rotate, and the speed reduction mechanism part comprises a speed reduction part and a drive part for driving the speed reduction part.

By configuring it in this way, the operating part can be oscillated using only the reduction mechanism that rotates part of the operating part, that is, using only the rotation mechanism. This makes it possible to reliably simplify the structure of the construction mechanism as it is motorized.

In the above configuration, the reduction gear unit may be an eccentric oscillating type reduction gear unit that includes a first member and a second member that rotate relatively around the same first rotation axis, and at least one crankshaft that is disposed between the first member and the second member and receives the power of the drive unit to rotate around a second rotation axis along the first rotation axis, and that reduces the rotation of the crankshaft and transmits it to the second member, thereby reducing the rotation of the second member relative to the first member.

In the above configuration, the crankshaft has a plurality of crankshafts, and has an external teeth member having external teeth that oscillates and rotates around the first axis of rotation by the crankshafts, the first member is a case having internal teeth that mesh with the external teeth, and the second member may be a carrier that rotatably supports the crankshafts and is rotatably supported by the first member via a bearing, and rotates at a reduced speed relative to the case by the crankshafts.

In the above configuration, the drive unit may be fixed to the first member.

In the above configuration, the action unit includes a boom rotatably supported on the main body, an arm rotatably supported on the boom on the opposite side to the main body, and an attachment rotatably supported on the arm on the opposite side to the boom, and the boom may be provided on the main body via the first reduction mechanism, the arm may be provided on the boom via the second reduction mechanism having a smaller torque transmission capacity than the first reduction mechanism, and the attachment may be provided on the arm via the third reduction mechanism having a smaller torque transmission capacity than the second reduction mechanism.

In the above configuration, the action unit includes a boom rotatably supported on the main body, an arm rotatably supported on the boom on the opposite side to the main body, and an attachment rotatably supported on the arm on the opposite side to the boom, and the boom may be provided on the main body via the first reduction mechanism, the arm may be provided on the boom via the second reduction mechanism that is lighter than the first reduction mechanism, and the attachment may be provided on the arm via the third reduction mechanism that is lighter than the second reduction mechanism.

In the above configuration, each of the reduction mechanism parts may be arranged so that the rotation axes of the reduction parts are aligned in the same direction.

In the above configuration, the main body has a support part that rotatably supports the action part, and the action part may include a boom whose side is rotatably supported by the support part, an arm rotatably supported on the side of the boom opposite the main body, and an attachment rotatably supported on the side of the arm opposite the boom.

In the above configuration, the action unit may include a boom that is long in one direction and rotatably supported on the main body, an arm that is rotatably supported on the side of the boom opposite the main body and in the short direction of the boom, and an attachment that is rotatably supported on the side of the arm opposite the boom and the same side on which the boom is disposed.

In the above configuration, the main body includes a self-propelled running body, a rotating body that rotates relative to the running body, and an operation room that is provided on the rotating body and arranged horizontally alongside the operating unit, and the drive unit may be arranged on the side of the operating unit facing the operation room.

In the above configuration, the main body includes a self-propelled running body, a rotating body that rotates relative to the running body, and an operation room that is provided on the rotating body and arranged horizontally alongside the operating unit, and the drive unit may be arranged on the side of the operating unit opposite the operation room.

A construction machine according to another aspect of the present invention includes a self-propelled main body, a reduction mechanism having a reduction unit and a drive unit for driving the reduction unit, a boom rotatably supported on the main body via a first reduction mechanism, an arm rotatably supported on the boom via a second reduction mechanism having a smaller torque transmission capacity than the first reduction mechanism, and an attach rotatably supported on the arm via a third reduction mechanism having a smaller torque transmission capacity than the second reduction mechanism.

With this configuration, the swinging motion of the boom relative to the main body, the swinging motion of the arm relative to the boom, and the swinging motion of the attachment relative to the arm can be performed by only the reduction mechanism parts, that is, by only the rotation mechanism. Therefore, as the construction machine is electrified, the structure of the construction machine can be reliably simplified.

In the above configuration, each of the reduction mechanism parts may be arranged so that the rotation axes of the reduction parts are aligned in the same direction.

The construction machinery described above can be simplified in structure by becoming electrified.

FIG. 1 is a schematic configuration diagram of a shovel according to an embodiment of the present invention, as viewed from the side. FIG. 1 is a schematic configuration diagram of a shovel according to an embodiment of the present invention, viewed from above. FIG. 2 is a cross-sectional view of a first reduction mechanism according to the embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line AA in FIG. 3 . FIG. 2 is a schematic configuration diagram of a shovel according to a first modified example of an embodiment of the present invention, as viewed from above. FIG. 13 is a schematic configuration diagram of an action portion according to a second modified example of the embodiment of the present invention, as viewed from above.

Next, an embodiment of the present invention will be described with reference to the drawings.

<Shovel>
Fig. 1 is a schematic diagram of a shovel 100 according to an embodiment of a construction machine of the present invention, as viewed from the side. In the following description, the front, which an operator (not shown) who operates the shovel 100 faces, will be referred to simply as the front, and the side horizontally opposite the front will be referred to simply as the rear. The up-down direction when the shovel 100 is placed on the road surface will be referred to simply as the up-down direction. The direction perpendicular to the fore-aft direction and the up-down direction will be referred to as the vehicle width direction. Fig. 1 shows the shovel 100 as viewed from the vehicle width direction.

As shown in FIG. 1, a shovel (an example of a construction machine in the claims) 100 includes a self-propelled running body (an example of a main body in the claims, a running body) 101, a rotating body (an example of a main body in the claims, a rotating body) 103 that is provided on the upper part of the running body 101 via a turning mechanism 102 and turns relative to the running body 101, and an action part 104 provided on the turning body 103. The running body 101 and the turning mechanism 102 are driven by, for example, an electric motor with a reduction gear (not shown). The running body 101 includes, for example, two caterpillars 105 aligned in the vehicle width direction. However, this is not limited to this, and wheels or the like may be used instead of the caterpillars 105.

FIG. 2 is a schematic configuration diagram of the shovel 100 as viewed from above.
An operation room 106 is provided at a position offset to one side on the front side of the rotating body 103. An operator operates the excavator 100 in this operation room 106. A plate-shaped support part 107 is provided adjacent to the operation room 106 on the front side of the rotating body 103 and approximately in the center in the vehicle width direction. The action part 104 is attached to this support part 107.

The working part 104 includes a boom 108 and an arm 109 that are long in the front-rear direction, and a bucket (an example of an attachment in the claims) 110. The boom 108, the arm 109, and the bucket 110 are rotatably connected via three reduction mechanisms 1, 2, and 3 (first reduction mechanism 1, second reduction mechanism 2, and third reduction mechanism 3).

Specifically, one longitudinal end 108a of the boom 108 is rotatably connected to the support 107 via the first reduction mechanism 1. One longitudinal end 109a of the arm 109 is rotatably connected to the other longitudinal end 108b of the boom 108 via the second reduction mechanism 2. The bucket 110 is rotatably connected to the other longitudinal end 109b of the arm 109 via the third reduction mechanism 3. The boom 108 is attached to the side 107a on the opposite side to the operation room 106 in the thickness direction of the support 107. The arm 109 is attached to the first side 108c on the opposite side to the operation room 106 in the short direction of the boom 108. The bucket 110 is attached to the first side 109c on the operation room 106 side in the short direction of the arm 109.

<First reduction mechanism>
FIG. 3 is a cross-sectional view of the first reduction mechanism.
The basic configuration of each of the reduction mechanism units 1 to 3 is the same. For this reason, in the following, of the reduction mechanism units 1 to 3, only the first reduction mechanism unit 1 will be described, and descriptions of the second reduction mechanism unit 2 and the third reduction mechanism unit 3 will basically be omitted, and will be described only when necessary.
As shown in FIG. 3, the first reduction gear mechanism 1 includes an electric motor (an example of a drive unit) 22 and a reduction gear unit 10 that reduces the rotation of a motor shaft 22a of the electric motor 22 and outputs the reduced rotation.

<Electric motor>
FIG. 4 is a cross-sectional view taken along line AA of FIG.
As shown in Fig. 3 and Fig. 4, the electric motor 22 is fastened to a first side surface 108c of the boom 108 by a bolt 120. A through hole 111 is formed in the boom 108 at a position corresponding to the electric motor 22, penetrating the boom 108 in the short direction. A motor shaft 22a of the electric motor 22 is inserted into this through hole 111. The motor shaft 22a protrudes toward the support portion 107. The axis of the motor shaft 22a coincides with a rotation axis C1 (an example of a first rotation axis in the claims) of the boom 108 relative to the support portion 107. In the following description, the direction of the rotation axis C1 is simply referred to as the axial direction, the radial direction of the motor shaft 22a is simply referred to as the radial direction, and the rotation direction of the motor shaft 22a is simply referred to as the circumferential direction.

<Reduction section>
The speed reducer 10 is fixed to a second side surface 108d of the boom 108 opposite to the first side surface 108c (the side of the operation room 106). The speed reducer 10 is arranged alongside the electric motor 22 in the direction of the rotation axis C1. The rotation axis of the speed reducer 10 also coincides with the axial direction.
The reduction unit 10 comprises a cylindrical case 11, a carrier 14 arranged radially inside the case 11, an input shaft 16 that provides a driving force to rotate the carrier 14, and a reduction output unit 18 (see Figure 5) that rotates the carrier 14 at a rotational speed that is reduced by a predetermined ratio relative to the rotational speed of the input shaft 16.

<Case>
An outer flange portion 11a that protrudes radially outward is integrally formed on the outer peripheral surface of the case 11. The outer flange portion 11a has a rectangular cross section along the axial direction. A second side surface 108d of the boom 108 is overlapped on an end surface 11b of the outer flange portion 11a on the boom 108 side in the axial direction. The case 11 is fastened and fixed to the boom 108 by a bolt 121. Internal teeth 24 are provided on the inner peripheral surface of the case 11. The internal teeth 24 are pin-shaped (cylindrical) teeth provided on the inner peripheral surface of the case 11. A plurality of internal teeth 24 are arranged at equal intervals in the circumferential direction.

<Career>
The carrier 14 is rotatably supported on the case 11 by a pair of main bearings (an example of the bearings in the claims) 26 arranged with a gap in the axial direction. The main bearings 26 are, for example, angular contact ball bearings. The carrier 14 is arranged coaxially with the case 11 and the rotation axis C1.

The carrier 14 comprises a disk-shaped end plate portion 30 arranged axially on the boom 108 side, a disk-shaped base portion 32 arranged axially on the support portion 107 side, and three cylindrical pillar portions 33 molded integrally with the base portion 32 and protruding from the base portion 32 toward the end plate portion 30.
The column portions 33 are disposed at equal intervals in the circumferential direction. The column portions 33 and the end plate portion 30 are fastened to each other by bolts 34 with the tip surface of the column portion 33 overlapping the end plate portion 30. In this state, a space having a predetermined width in the axial direction is formed between the base portion 32 and the end plate portion 30.

A bolt fastening hole 33a into which a bolt 34 is fastened is formed in the column portion 33. The bolt 34 is inserted into the bolt insertion hole 30a from the opposite side of the column portion 33 across the end plate portion 30, and is fastened into the bolt fastening hole 33a of the column portion 33. A pin 36 for positioning the end plate portion 30 with respect to the base plate portion 32 is provided slightly radially inward from the bolt 34. The pin 36 is disposed so as to straddle the column portion 33 and the end plate portion 30.
It is to be noted that the pillar portion 33 does not have to be formed integrally with the base plate portion 32. In this case, the pillar portion 33 is fastened to the base plate portion 32. The pillar portion 33 is not limited to being cylindrical. It is sufficient that the pillar portion 33 forms a space having a predetermined width in the axial direction between the base plate portion 32 and the end plate portion 30.

A side surface 107a of the support portion 107 is overlapped with a surface 32c of the base portion 32 opposite to the end plate portion 30. In this state, the base portion 32 is fastened and fixed to the side surface 107a of the support portion 107 by a bolt 122.
Further, the end plate portion 30 and the base plate portion 32 each have a plurality of through holes 30c, 32b (for example, three in this embodiment) into which a crankshaft 46 (described later) of the reduction output portion 18 is inserted. The through holes 30c, 32b are disposed at equal intervals in the circumferential direction.
Furthermore, through holes 30b, 32a that penetrate in the axial direction are formed in the radial centers of the end plate portion 30 and the base plate portion 32. The input shaft 16 is inserted into these through holes 30b, 32a. The input shaft 16 is disposed coaxially with the case 11 and the rotation axis C1.

A base end 16a of the input shaft 16 on the electric motor 22 side is coupled to a motor shaft 22a, so that the input shaft 16 rotates integrally with the motor shaft 22a.
A tip end 16b of the input shaft 16 on the opposite side to the electric motor 22 (the support portion 107 side) is disposed within the through hole 32a of the base portion 32. A drive gear 42 made of an external gear is integrally provided on the tip end 16b of the input shaft 16.

<Deceleration output section>
The reduction output unit 18, which rotates the carrier 14, rotates the carrier 14 at a rotation speed that is reduced by a predetermined ratio relative to the rotation speed of the input shaft 16. The reduction output unit 18 includes a plurality of transmission gears 44 (e.g., three in this embodiment) that mesh with the drive gear 42, a plurality of crankshafts 46 (e.g., three in this embodiment) that have one ends fixed to the transmission gears 44, and a first externally toothed gear (an example of an externally toothed member in the claims) 48a and a second externally toothed gear (an example of an externally toothed member in the claims) 48b that oscillate and rotate in conjunction with the rotation of the crankshafts 46.

Since the transmission gear 44 is fixed to one end of the crankshaft 46 , the rotation of the motor shaft 22 a is transmitted to the crankshaft 46 via the transmission gear 44 .
The crankshaft 46 is disposed parallel to the input shaft 16. That is, the crankshaft 46 rotates about a crank rotation axis C20 (an example of a second rotation axis in the claims) parallel to the rotation axis C1. The crankshaft 46 is rotatably supported by the end plate portion 30 via a first crank bearing 51. The crankshaft 46 is rotatably supported by the base plate portion 32 via a second crank bearing 52. The first crank bearing 51 and the second crank bearing 52 are, for example, tapered roller bearings.

A first eccentric portion 46a and a second eccentric portion 46b are formed in the axial center of the crankshaft 46, and are eccentric from the axial center of the crankshaft 46. The first eccentric portion 46a and the second eccentric portion 46b are disposed adjacent to each other in the axial direction between the first crank bearing 51 and the second crank bearing 52. The first eccentric portion 46a is adjacent to the first crank bearing 51. The second eccentric portion 46b is adjacent to the second crank bearing 52. The first eccentric portion 46a and the second eccentric portion 46b are also out of phase with each other.

Such crankshafts 46 are inserted into the through holes 30c, 32b of the end plate portion 30 and the base plate portion 32. That is, the crankshafts 46 are also arranged at equal intervals in the circumferential direction, similar to the through holes 30c, 32b.

A first roller bearing 55a is attached to the first eccentric portion 46a of the crankshaft 46. A second roller bearing 55b is attached to the second eccentric portion 46b. The first roller bearing 55a is, for example, a cylindrical roller bearing. The first roller bearing 55a has a number of rollers 56 and a cage 57 that holds the rollers 56. The second roller bearing 55b has a similar configuration to the first roller bearing 55a, so a detailed description thereof is omitted. The first external gear 48a and the second external gear 48b are oscillated and rotated via the roller bearings 55a and 55b as the crankshaft 46 rotates.

The first external gear 48a and the second external gear 48b are disposed in the space between the base plate portion 32 and the end plate portion 30 of the carrier 14. The first external gear 48a and the second external gear 48b have external teeth 49a, 49b that mesh with the internal teeth 24 of the case 11.
The first external gear 48a and the second external gear 48b are formed with a first through hole 48c into which the input shaft 16 is inserted, a second through hole 48d into which the column portion 33 is inserted, and a third through hole 48e into which the eccentric portions 46a, 46b of the crankshaft 46 are inserted.

The first eccentric portion 46a of the crankshaft 46 and the first roller bearing 55a are inserted into the third through hole 48e of the first external gear 48a. The second eccentric portion 46b of the crankshaft 46 and the second roller bearing 55b are inserted into the third through hole 48e of the second external gear 48b. As a result, as the first and second eccentric portions 46b rotate in an oscillating manner due to the rotation of the crankshaft 46, the first external gear 48a and the second external gear 48b are oscillatingly rotated while meshing with the internal teeth 24 of the case 11.

A first washer 59 is provided between the first crank bearing 51 and the first roller bearing 55a. The first washer 59 is fitted onto the outer circumferential surface of the crankshaft 46. The first washer 59 is disposed on the end surface of the first eccentric portion 46a opposite to the second eccentric portion 46b.
A second washer 60 is provided between the second crank bearing 52 and the second roller bearing 55b. The second washer 60 is fitted to the outer peripheral surface of the crankshaft 46. The second washer 60 is disposed on the end surface of the second eccentric portion 46b opposite to the first eccentric portion 46a. The outer diameter of the second washer 60 is the same as the outer diameter of the first washer 59.

<Arrangement of second reduction mechanism and third reduction mechanism>
As described above, the basic configuration of the second reduction mechanism 2 and the third reduction mechanism 3 is the same as the configuration of the first reduction mechanism 1. However, the mounting orientation of the second reduction mechanism 2 and the third reduction mechanism 3 is different from that of the first reduction mechanism 1. The arrangement of the second reduction mechanism 2 and the third reduction mechanism 3 will be described below with reference to Fig. 3 and based on Fig. 2.

First, the arrangement of the second reduction mechanism 2 will be described.
In addition, the reference numerals of the second reduction mechanism 2 and the third reduction mechanism 3 and the reference numerals of the bolts for fixing these reduction mechanisms 2, 3 are the same as those of the first reduction mechanism 1 described above.
In the second reduction gear mechanism 2, the electric motor 22 is fastened to the second side surface 108d of the boom 108 by a bolt 120. That is, the electric motor 22 of the second reduction gear mechanism 2 protrudes from the boom 108 toward the operation chamber 106 side.

Further, the first side surface 108c of the boom 108 is overlapped on the end surface 11b of the outer flange portion 11a integrally formed with the case 11 of the second reduction gear mechanism 2 on the boom 108 side. The case 11 is fastened and fixed to the boom 108 by the bolts 121.
Furthermore, a first side surface 109c of the arm 109 is placed on a surface 32c of the base plate portion 32 in the second reduction gear mechanism 2, the surface 32c being opposite to the end plate portion 30. In this state, the base plate portion 32 is fastened and fixed to the first side surface 109c of the arm 109 by a bolt 122.

Next, the arrangement of the third reduction mechanism 3 will be described.
In the third reduction gear mechanism 3, the electric motor 22 is fastened to a first side surface 112a on the operation chamber 106 side of an attachment stay 112 provided on the bucket 110 by a bolt 120. That is, the electric motor 22 of the third reduction gear mechanism 3 protrudes from the arm 109 toward the operation chamber 106 side.

Further, in the outer flange portion 11a integrally formed with the case 11 of the third reduction gear mechanism 3, a second side surface 112b opposite to the first side surface 112a of the mounting stay 112 is overlapped with an end surface 11b on the mounting stay 112 side of the bucket 110. The case 11 is fastened and fixed to the bucket 110 by bolts 121.
Furthermore, a first side surface 109c of the arm 109 is overlapped on a surface 32c of the base plate portion 32 in the third reduction gear mechanism 3, the surface 32c being opposite to the end plate portion 30. In this state, the base plate portion 32 is fastened and fixed to the first side surface 109c of the arm 109 by a bolt 122.

Here, the axis of the motor shaft 22a in the second reduction mechanism 2 coincides with the rotation axis C2 of the arm 109 relative to the boom 108. The axis of the motor shaft 22a in the third reduction mechanism 3 coincides with the rotation axis C3 of the bucket 110 relative to the arm 109. In other words, the reduction mechanisms 1 to 3 are arranged so that their rotation axes C1 to C3 are parallel to each other.

<Operation of the action part>
Next, the operation of the action portion 104 will be described.
First, a case where the first reduction mechanism portion 1 is driven will be described.
When the electric motor 22 of the first reduction gear mechanism 1 is driven, the input shaft 16 is driven integrally with the motor shaft 22a. Then, the rotation of the input shaft 16 rotates the transmission gear 44 via the drive gear 42. As a result, the crankshaft 46 rotates integrally with the transmission gear 44 about the crank rotation axis C20.

When the crankshaft 46 rotates, the first external gear 48a rotates while meshing with the internal teeth 24 in response to the oscillation of the first eccentric portion 46a, and the second external gear 48b rotates while meshing with the internal teeth 24 in response to the oscillation of the second eccentric portion 46b. In other words, the crankshaft 46 rotates about the crank rotation axis C20 and revolves around the rotation axis C1.

In this embodiment, the column portion 33 penetrating the second through hole 48d of both external gears 48a, 48b is fixed in a fixed position together with the base plate portion 32. This causes the carrier 14 to rotate at a reduced rotation speed relative to the case 11 compared to the input shaft 16. Here, since the base plate portion 32 of the carrier 14 is fastened and fixed to the support portion 107, the case 11 rotates at a reduced rotation speed relative to the carrier 14 compared to the input shaft 16. Since the boom 108 is fastened and fixed to the case 11 by the bolt 121, the boom 108 rotates around the rotation axis C1. In other words, the boom 108 is swung relative to the rotating body 103.

When the electric motors 22 of the second reduction mechanism 2 and the third reduction mechanism 3 are driven, the arm 109 and the bucket 110 are swung in the same manner as described above. That is, when the electric motor 22 of the second reduction mechanism 2 is driven, the arm 109 is swung relative to the boom 108. When the electric motor 22 of the third reduction mechanism 3 is driven, the bucket 110 is swung relative to the arm 109.

When the boom 108 is swung by the first reduction mechanism 1, the weights of the arm 109 and second reduction mechanism 2 connected to the other longitudinal end 108b of the boom 108, and the bucket 110 and third reduction mechanism 3 connected to the other longitudinal end 109b of the arm 109 also act. When the arm 109 is swung by the second reduction mechanism 2, the weights of the bucket 110 and third reduction mechanism 3 connected to the other longitudinal end 109b of the arm 109 also act. When the bucket 110 is swung by the third reduction mechanism 3, only the weight of the bucket 110 acts.

Therefore, among the three reduction mechanism sections 1 to 3, the first reduction mechanism section 1 has the largest transmission torque capacity. The second reduction mechanism section 2 has a smaller transmission torque capacity than the first reduction mechanism section 1. Among the three reduction mechanism sections 1 to 3, the third reduction mechanism section 3 has the smallest transmission torque capacity, and the transmission torque capacity of the third reduction mechanism section 3 is smaller than the transmission torque capacity of the second reduction mechanism section 2. In other words, among the three reduction mechanism sections 1 to 3, the first reduction mechanism section 1 has the largest physical size and is also the heaviest. The physical size of the second reduction mechanism section 2 is smaller than the physical size of the first reduction mechanism section 1. In addition, the weight of the second reduction mechanism section 2 is lighter than the weight of the first reduction mechanism section 1. Among the three reduction mechanism sections 1 to 3, the third reduction mechanism section 3 has the smallest physical size and is also the lightest.

In this manner, in the above-described embodiment, the boom 108, arm 109, and bucket 110 provided on the rotating body 103 of the self-propelled shovel 100 are connected via the reduction mechanism units 1 to 3. Therefore, the boom 108, arm 109, and bucket 110 can be swung by only the reduction mechanism units 1 to 3, that is, by only the rotation mechanism. Therefore, by electrifying the shovel 100, the structure of the shovel 100 can be reliably simplified.

The reduction mechanism 10 of the reduction mechanism 1-3 includes a cylindrical case 11, a carrier 14 arranged radially inside the case 11, an input shaft 16 that applies a driving force to rotate the carrier 14, and a reduction output unit 18 that rotates the carrier 14 at a rotation speed reduced by a predetermined ratio to the rotation speed of the input shaft 16. The reduction output unit 18 includes a plurality of crankshafts 46, and a first external gear 48a and a second external gear 48b that oscillate and rotate with the rotation of the crankshaft 46. Therefore, the reduction mechanism 1-3 can obtain a high output with a high reduction ratio, so that the reduction mechanism 1-3 can be made compact while the boom 108, the arm 109, and the bucket 110 can be operated smoothly.

Moreover, the carrier 14 of the reduction mechanism units 1 to 3 is rotatably supported on the case 11 by a pair of main bearings 26 spaced apart in the axial direction. In other words, the arm 109 can be rotatably supported relative to the boom 108 by the main bearings 26 provided in the reduction mechanism units 1 to 3, and the bucket 110 can be rotatably supported relative to the arm 109. Therefore, no bearings are required to rotatably support each unit separately from the reduction mechanism units 1 to 3, and the structure of the excavator 100 can be further simplified.

In addition, in the second reduction mechanism section 2, the electric motor 22 is attached to the boom 108 side. When the arm 109 is swung relative to the boom 108, the boom 108 remains in a fixed position and the arm 109 is rotated. In other words, by attaching the electric motor 22 to the boom 108 side, which does not move and remains in a fixed position, the weight of the electric motor 22 is not affected when the arm 109 is swung, and the inertia when the arm 109 is swung can be reduced.

Moreover, in the second reduction gear mechanism 2, the electric motor 22 protrudes from the boom 108 toward the operation room 106, so that the electric motor 22 of the second reduction gear mechanism 2 can be easily seen from the operation room 106. Therefore, when the operator operates the excavator 100, the electric motor 22 of the second reduction gear mechanism 2 will not be accidentally hit, and damage to the electric motor 22 can be suppressed.
The same applies to the electric motor 22 of the third reduction gear mechanism 3. Since the electric motor 22 of the third reduction gear mechanism 3 also protrudes from the arm 109 toward the operation chamber 106, damage to the electric motor 22 can be suppressed.

The transmission torque capacity, size, and weight of each of the reduction mechanism parts 1 to 3 are changed depending on the mounting location of each of the reduction mechanism parts 1 to 3. In other words, the transmission torque capacity, size, and weight of each of the reduction mechanism parts 1 to 3 are reduced toward the front of the action part 104. This allows the action part 104 to be made smaller overall without unnecessarily increasing the size of each of the reduction mechanism parts 1 to 3.

The reduction mechanism units 1 to 3 are arranged so that the rotation axes C1 to C3 are parallel to each other. This allows the boom 108, arm 109, and bucket 110 that make up the action unit 104 to swing in the same direction (the front-to-rear direction perpendicular to the rotation axes C1 to C3), improving the operability of the excavator 100.

The boom 108 constituting the action part 104 is attached to the side surface 107a on the opposite side to the operation room 106 in the thickness direction of the support part 107. The arm 109 is attached to the first side surface 108c on the opposite side to the operation room 106 in the short direction of the boom 108. The bucket 110 is attached to the first side surface 109c on the operation room 106 side in the short direction of the arm 109. In other words, the arm 109 is arranged on the opposite side to the operation room 106 across the boom 108. Therefore, the operator feels less pressure from the arm 109 compared to when the arm 109 is arranged on the operation room 106 side. This improves the operability of the excavator 100.

In the above embodiment, the reduction mechanism units 1 to 3 have been described as having the electric motor 22 fastened to the case 11 via the mounting stays 112 of the boom 108 and bucket 110. However, this is not limited to the above, and the electric motor 22 may be fastened to the carrier 14. In this case, the mounting stays 112 of the boom 108 and bucket 110 are fixed to the carrier 14, and the electric motor 22 is fastened to the carrier 14 via the boom 108 and mounting stays 112. Meanwhile, the support unit 107 and arm 109 are fastened to the case 11.

[First Modification]
Next, a first modification of the embodiment will be described with reference to FIG.
5 is a schematic configuration diagram of the shovel 100 in the first modified example seen from above. Note that the same reference numerals are used to designate the same aspects as in the embodiment, and the description thereof will be omitted (the same applies to the following modified examples).
The difference between the above-described embodiment and the modified example is that the positions of the boom 108, the arm 109, and the bucket 110 are different, and the orientations of the second reduction mechanism 2 and the third reduction mechanism 3 are different.

Specifically, in the first modified example, the arm 109 is attached to the second side surface 108d on the side of the operation room 106 in the short direction of the boom 108. The bucket 110 is attached to the second side surface 109d on the side opposite the operation room 106 in the short direction of the arm 109.

In the second reduction gear mechanism 2, the electric motor 22 is fastened to the first side surface 108c of the boom 108 by a bolt 120. That is, the electric motor 22 of the second reduction gear mechanism 2 protrudes from the boom 108 toward the opposite side to the operation chamber 106.
Further, the second side surface 108d of the boom 108 is overlapped on the end face 11b of the outer flange portion 11a integrally formed with the case 11 of the second reduction gear mechanism 2. The case 11 is fastened and fixed to the boom 108 by the bolts 121.
Furthermore, a second side surface 109d of the arm 109 is placed on a surface 32c of the base plate portion 32 in the second reduction gear mechanism 2, the surface 32c being opposite to the end plate portion 30. In this state, the base plate portion 32 is fastened and fixed to the second side surface 109d of the arm 109 by a bolt 122.

On the other hand, in the third reduction gear mechanism 3, the electric motor 22 is fastened to a second side surface 112b of a mounting stay 112 provided on the bucket 110 by a bolt 120. That is, the electric motor 22 of the third reduction gear mechanism 3 protrudes from the arm 109 toward the opposite side to the operation chamber 106.
Further, in the outer flange portion 11a integrally formed with the case 11 of the third reduction gear mechanism 3, a first side surface 112a of the mounting stay 112 is overlapped with an end face 11b of the bucket 110 on the mounting stay 112 side. The case 11 is fastened and fixed to the bucket 110 by bolts 121.
Furthermore, a second side surface 109d of the arm 109 is placed on a surface 32c of the base plate portion 32 in the third reduction gear mechanism 3, the surface 32c being opposite to the end plate portion 30. In this state, the base plate portion 32 is fastened and fixed to the second side surface 109d of the arm 109 by a bolt 122.

Therefore, according to the above-mentioned first modified example, the same effects as those of the above-mentioned embodiment are achieved.
Moreover, the arm 109 is attached to a second side surface 108d on the operator room 106 side in the short side direction of the boom 108. The bucket 110 is attached to a second side surface 109d on the opposite side to the operator room 106 in the short side direction of the arm 109. In the second reduction gear mechanism 2, the electric motor 22 protrudes from the boom 108 toward the opposite side to the operator room 106. In the third reduction gear mechanism 3, the electric motor 22 protrudes from the arm 109 toward the opposite side to the operator room 106. This makes it possible to prevent the electric motor 22 from obstructing the view from the operator room 106. This makes it possible to improve the operability of the excavator 100.

[Second Modification]
Next, a second modification of the embodiment will be described with reference to FIG.
FIG. 6 is a schematic configuration diagram of the action portion 104 in the second modified example, viewed from above.
6, the difference between the embodiment and the second modified example is that, in the acting unit 104 of the embodiment, an arm 109 is disposed on a first side surface 108c of a boom 108 and is supported at one end relative to the boom 108, whereas in the second modified example, the arm 109 is supported at both ends relative to the boom 108. Also, in the acting unit 104 of the embodiment, a bucket 110 is disposed on a first side surface 109c of the arm 109 and is supported at one end relative to the arm 109, whereas in the second modified example, the bucket 110 is supported at both ends relative to the arm 109.

Specifically, in the second modified example, two support parts 207a, 207b (first support part 207a, second support part 207b) for supporting the boom 108 are provided. The two support parts 207a, 207b are arranged on both side surfaces 108c, 108d of the boom 108 on the side of the longitudinal end 108a. The two support parts 207a, 207b support the longitudinal end 108a of the boom 108 so that it can rotate freely (supported at both ends). Of the two support parts 207a, 207b, the second support part 207b is arranged on the opposite side of the boom 108 from the operation room 106 (the right side in FIG. 6), and the electric motor 22 of the first reduction mechanism part 1 is fixed to the second support part 207b. In addition, the reduction part 10 of the first reduction mechanism part 1 is arranged between the second support part 207b and the boom 108.

At the other longitudinal end 108b of the boom 108, two boom support parts 208a, 208b (first boom support part 208a, second boom support part 208b) are provided protruding along the longitudinal direction of the boom 108. One longitudinal end 109a of the arm 109 is disposed between the two boom support parts 208a, 208b. The one longitudinal end 109a of the arm 109 is rotatably supported (supported at both ends) by the two boom support parts 208a, 208b. The electric motor 22 of the second reduction mechanism part 2 is fixed to one of the two boom support parts 208a, 208b (in FIG. 6, the second boom support part 208b on the right side in the figure). In addition, the speed reducer 10 of the second speed reduction mechanism 2 is disposed between one of the two boom supports 208a, 208b (the second boom support 208b on the right side in FIG. 6) and the arm 109. Note that the electric motor 22 may be fixed to the first boom support 208a on the left side in FIG. 6, and the speed reducer 10 may be disposed between the first boom support 208a and the arm 109.

Two bucket support parts 212a, 212b (first bucket support part 212a, second bucket support part 212b) are provided on the mounting stay 112 of the bucket 110, protruding along the longitudinal direction of the arm 109. The other longitudinal end 109b of the arm 109 is disposed between the two bucket support parts 212a, 212b. The two bucket support parts 212a, 212b are rotatably supported on the other longitudinal end 109b of the arm 109. The electric motor 22 of the third reduction mechanism part 3 is fixed to one of the two bucket support parts 212a, 212b (in FIG. 6, the second bucket support part 212b on the right side in the figure). In addition, the reduction gear unit 10 of the third reduction mechanism 3 is disposed between one of the two bucket support parts 212a, 212b (the second bucket support part 212b on the right side in FIG. 6) and the arm 109. Note that the electric motor 22 may be fixed to the first bucket support part 212a on the left side in FIG. 6, and the reduction gear unit 10 may be disposed between the first bucket support part 212a and the arm 109.

Therefore, according to the above-mentioned second modified example, the same effects as those of the above-mentioned embodiment are achieved.
In addition, the arm 109 is supported at both ends by the boom 108, and the bucket 110 is supported at both ends by the arm 109. Therefore, compared to the above-described embodiment, it is possible to increase the strength of the connection between the support parts 207a, 207b and the boom 108, the connection between the boom 108 (boom support parts 208a, 208b) and the arm 109, and the connection between the arm 109 and the bucket 110 (bucket support parts 212a, 212b). Also, it is possible to stabilize the operation of the action part 104.

The present invention is not limited to the above-described embodiment and each of the modifications, but includes various modifications to the above-described embodiment without departing from the spirit of the present invention.
For example, in the above-mentioned embodiment and each modified example, the construction machine is described as a shovel 100. However, the present invention is not limited to this, and the configurations of the reduction mechanism units 1 to 3 described above can be adopted for various construction machines such as bulldozers, motor graders, forklifts, and wheel loaders. Depending on the application of the construction machine, various tools (various attachments such as hooks) can be attached instead of the bucket 110.

In the above-mentioned embodiment and each modified example, a case has been described in which a self-propelled running body 101 and a rotating body 103 that is provided on the upper part of the running body 101 via a rotating mechanism 102 and rotates relative to the running body 101 are provided. Then, a case has been described in which an action part 104 is provided on such a rotating body 103. However, this is not limited to this, and any self-propelled vehicle body (main body part) may be used as long as the action part 104 is provided on this vehicle body.

In the above-described embodiment and each modified example, the reduction gear unit 10 of the reduction mechanism units 1 to 3 is described as including a cylindrical case 11, a carrier 14 arranged radially inside the case 11, an input shaft 16 that applies a driving force to rotate the carrier 14, and a reduction output unit 18 that rotates the carrier 14 at a rotation speed that is reduced by a predetermined ratio relative to the rotation speed of the input shaft 16. The reduction output unit 18 is described as being an eccentric oscillating type reduction gear unit that is including a plurality of crankshafts 46 and a first external gear 48a and a second external gear 48b that oscillate and rotate in association with the rotation of the crankshafts 46. However, the reduction gear unit 10 is not limited to this, and may be an eccentric oscillating type reduction gear unit that includes a first member (e.g., case 11) and a second member (e.g., carrier 14) that rotate relatively around the same rotation axis C1, and at least one crankshaft (e.g., crankshaft 46) that is disposed between the first and second members and receives the power of the drive unit and rotates around a second rotation axis along the first rotation axis, reducing the rotation of the crankshaft and transmitting it to the second member, thereby reducing the rotation of the second member relative to the first member.

In the above-described embodiment and each modified example, the reduction mechanism units 1 to 3 are arranged so that the rotation axes C1 to C3 are parallel to each other. However, this is not limited to the above, and the rotation axes C1 to C3 do not have to be completely parallel to each other. The rotation axes of the reduction mechanism units 1 to 3 only need to be aligned in the same direction.
In the above-described embodiment and each modified example, the case has been described in which the action unit 104 is composed of the boom 108, the arm 109, and the bucket 110. However, this is not limited thereto, and it is sufficient that at least a part of the action unit 104 is provided rotatably (swingably) via the reduction mechanism units 1 to 3.

1...first reduction mechanism (reduction mechanism, first reduction mechanism), 2...second reduction mechanism (reduction mechanism, second reduction mechanism), 3...third reduction mechanism (reduction mechanism, third reduction mechanism), 10...reduction section, 11...case (first member), 14...carrier (second member), 22...electric motor (driving section), 26...main bearing (bearing), 46...crankshaft, 48a...first external gear (external gear), 48b...second external gear (external gear), 49a, 49b...external teeth, 100...shovel (construction machine), 101...running body (main body), 103...swivel body (main body), 104...working section, 106...operation room, 107...support section, 1 07a...side, 108...boom, 108c, 109c...first side (side), 108d, 109d...second side (side), 109...arm, 110...bucket (attachment), 112...mounting stay, 112a...first side, 112b...second side, 207a...first support part (support), 207b...second support part (support), 208a...first boom support part (boom), 208b...second boom support part (boom), 212a...first bucket support part (attachment), 212b...second bucket support part (attachment), C1-C3...rotation axis (first rotation axis), C20...crank rotation axis (second rotation axis)

Claims (3)

A self-propelled main body;
A boom rotatably supported on the main body;
an arm rotatably supported on an opposite side of the boom from the main body;
an attach supported rotatably on the arm on an opposite side to the boom;
a first reduction mechanism provided at a connection portion between the boom and the arm for driving the boom and the arm to rotate relative to each other;
a second reduction mechanism provided at a connection between the arm and a mounting stay of the attachment, for driving the arm and the attachment to rotate relative to each other;
Equipped with
The first reduction mechanism unit includes:
A first reduction gear portion;
a first drive unit that drives the first reduction gear unit;
Equipped with
The second reduction mechanism portion includes:
A second reduction gear portion;
a second drive unit that drives the second reduction gear unit;
Equipped with
the first reduction gear mechanism has the first drive unit mounted and fixed on one side surface of the boom and the first reduction gear unit mounted and fixed on the other side surface of the boom,
The second reduction mechanism is configured such that the second drive unit is placed and fixed on the same side surface of the mounting stay as the side on which the first drive unit is fixed, and the second reduction unit is placed and fixed on the same side surface of the mounting stay as the side on which the first reduction unit is fixed.
Construction machinery. The main body portion is
A self-propelled vehicle;
A rotating body that rotates relative to the traveling body;
An operation room provided on the rotating body and arranged horizontally alongside the boom;
Including,
the first reduction gear mechanism unit has the first drive unit fixed to a side surface of the boom on the operation room side, and the first reduction gear unit fixed to a side surface of the boom opposite to the operation room side,
The second reduction mechanism unit has the second drive unit fixed to a side surface of the mounting stay facing the operation chamber, and the second reduction unit fixed to a side surface of the mounting stay opposite the operation chamber.
2. The construction machine according to claim 1. The main body portion is
A self-propelled vehicle;
A rotating body that rotates relative to the traveling body;
An operation room provided on the rotating body and arranged horizontally alongside the boom;
Including,
the first reduction gear mechanism unit has the first drive unit fixed to a side surface of the boom opposite to the operation room, and the first reduction gear unit fixed to a side surface of the boom on the operation room side,
The second reduction mechanism has the second drive unit fixed to a side surface of the mounting stay opposite the operation chamber, and the second reduction unit fixed to a side surface of the mounting stay facing the operation chamber.
2. The construction machine according to claim 1.

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