Drive transmission device and construction machine

Abstract

To provide a drive transmission device capable of reducing a gap adjustment work using an electric actuator.SOLUTION: A drive transmission device 1 comprises: a first component 109 and a second component 110 that are rotatably coupled around a rotation axis C2; a driving source 120 for generating torque for driving both of the first component and the second component; a deceleration units 3A, 3B for transmitting torque from the driving source to the second component; at least two bracket units 112 that are arranged along a rotation axis direction at the second component; and flange units 111 that extend in a direction crossing the rotation axis and connect the deceleration units and the bracket units with an overlapping region overlapped with the bracket units when viewed in a direction along the rotation axis. In the overlapping region, a regulation unit 113 that extends in the direction along the rotation axis to regulate relative rotational movement of the bracket units and the flange units and a reception unit for receiving the regulation unit are provided.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a drive transmission device and a construction machine, and more particularly to a technique suitable for use in a connecting portion actuator for an excavator.

Background Art

[0002] For example, a construction machine such as a hydraulic excavator includes a traveling body that travels and a revolving body that is rotatably provided on the traveling body. The revolving body includes an operation cab on which an operator rides. Further, the revolving body is provided with an operating portion having one end rotatably (oscillatably) connected thereto. Examples of the operating portion include a boom, an arm having one end rotatably connected to the other end of the boom on the side opposite to the revolving body, and a bucket having one end rotatably connected to the other end of the arm on the side opposite to the boom.

[0003] In many cases, a hydraulic actuator of a linear motion mechanism is provided as a drive transmission device at the connecting portion between the revolving body and the boom, the connecting portion between the boom and the arm, and the connecting portion between the arm and the bucket. By driving the hydraulic actuator, the revolving body is caused to rotate with respect to the traveling body, or the boom, the arm, and the bucket are caused to swing. In a conventional connecting portion between an arm and a bucket, a rotating member is rotatably coupled by a pin. In this structure, since there is play in the rotational axis direction at the connecting portion, gap adjustment at the connecting portion is unnecessary. Further, the bucket or the like may be replaced with a different attachment.

[0004] By the way, in recent years, electrification has been desired from the viewpoint of simplifying the structure of construction machines. For this reason, it has been proposed to use a rotary electric actuator as a drive transmission device. Further, when a rotary actuator is applied to the connecting portion, in order to cope with the moment generated in the rotational axis direction, a structure in which the rotary actuators are arranged in series in the rotational axis direction can be considered.

[0005] In such a connecting portion, when the rotary actuators are arranged in series in the rotational axis direction, the mounting width for the rotary actuators in the rotational axis direction is fixed. Also, the mounting width of attachments such as buckets in the rotational axis direction is fixed.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in a structure in which rotary electric actuators are arranged in series in the rotational axis direction at the connecting portion, there is a gap that allows those with fixed mounting widths to be attached to each other, so there is a problem that adjustment is required using shims, spacers, etc. Furthermore, when exchanging with different attachments such as buckets, gap adjustment with respect to the mounting width of the rotary electric actuator is required for each attachment. There is a demand to shorten the gap adjustment work due to such a mismatch in the mounting span, or to reduce the number of work steps.

[0008] The present invention provides a drive transmission device that serves as a connecting portion capable of reducing gap adjustment work even when using an electric actuator, and a construction machine equipped with this drive transmission device.

Means for Solving the Problems

[0009] (1) The drive transmission device according to one aspect of the present invention is a speed reduction unit that transmits the rotational force from the drive source to a second member that is attached to the first member and rotatably connected to the first member about the rotational axis, at least two bracket portions that are spaced apart along the rotational axis direction and arranged on the second member A flange portion that extends in a direction intersecting the rotation axis and has an overlapping region that overlaps the bracket portion when viewed in the direction along the rotation axis, and connects the reduction portion and the bracket portion. Comprising: In the overlapping region, a restricting portion that extends in the direction along the rotation axis and restricts relative rotational movement around the rotation axis in the bracket portion and the flange portion, and a receiving portion that receives the restricting portion are provided.

[0010] With this configuration, the second member can be rotationally driven with respect to the first member via the reduction portion, the flange portion, and the bracket portion by the rotational driving force of the drive source. Moreover, between the flange portion and the bracket portion, it becomes possible to perform position regulation and attitude regulation around the rotation axis while allowing dimensional errors in the rotation axis direction by the restricting portion and the receiving portion. At the same time, the restricting portion and the receiving portion can allow relative movement in the direction along the rotation axis between the bracket portion and the flange portion based on the separation distance of the bracket portion in the direction along the rotation axis. As a result, when assembling and connecting the second member and the first member, it becomes possible to easily assemble without worrying about dimensional errors in the rotation axis direction or the assembling attitude of the second member and the first member, and it becomes possible to improve workability. Thereby, when replacing the second member with respect to the first member, it becomes possible to easily assemble without worrying about dimensional errors in the rotation axis direction or the assembling attitude of the second member and the first member, and it becomes possible to improve workability.

[0011] (2) In the drive transmission device according to one aspect of the present invention, in the above (1), a plurality of sets of the receiving portion and the restricting portion are arranged around the rotation axis. The receiving portion can have a round cross-sectional contour in a direction intersecting the rotation axis. Here, the plurality of sets around the rotation axis includes both the case where they are arranged in the radial direction with respect to the rotation axis and the case where they are arranged in the circumferential direction with respect to the rotation axis. Further, the direction in which the receiving portion intersects the rotation axis can include not only these orthogonal cross-sections but also inclined cross-sections.

[0012] (3) In one aspect of the drive transmission device according to the present invention, in the above (1), one set of the receiving portion and the restricting portion is arranged around the rotation axis. The receiving portion can have a polygonal cross-sectional contour in a direction intersecting the rotation axis. Here, for the cross-sectional shape of the receiving portion to be polygonal, it is only necessary that the restricting portion can maintain a state of not rotating around its axis with respect to the connected receiving portion. For example, cases where a part of the polygon is formed by a curve or only a curve is formed can also be included. Also, the cross-sectional shape of the receiving portion and the cross-sectional shape of the restricting portion may or may not match each other.

[0013] (4) In one aspect of the drive transmission device according to the present invention, in the above (2) or (3), the restricting portion is a restricting pin extending in a direction along the rotation axis. The receiving portion can be a through-hole formed in the bracket portion and the flange portion through which the restricting pin passes.

[0014] (5) In one aspect of the drive transmission device according to the present invention, in any of the above (1) to (4), at least two of the deceleration portions are arranged at intervals along the rotation axis direction in the first member. The flange portion is connected to each of the deceleration portions. In the rotation axis direction, the bracket portions spaced apart in the rotation axis direction can all be located inside and sandwiched by the flange portion.

[0015] (6) In one aspect of the present invention, the drive transmission device according to any one of (1) to (4) above is such that in the first member, at least two of the reduction portions are arranged to be spaced apart from each other along the rotational axis direction, the flange portion is connected to each of the reduction portions, in the rotational axis direction, the bracket portions spaced apart in the rotational axis direction can both be located outside the flange portion.

[0016] (7) In one aspect of the present invention, the drive transmission device according to any one of (1) to (4) above is such that in the first member, at least two of the reduction portions are arranged to be spaced apart from each other along the rotational axis direction, the flange portion is connected to each of the reduction portions, in the rotational axis direction, one of the flange portions is located inside and sandwiched by the bracket portions spaced apart in the rotational axis direction, and the restricting portion is a restricting pin extending in the direction along the rotational axis, the receiving portion can be a through hole formed in the bracket portion and one of the flange portions through which the restricting pin penetrates.

[0017] (8) The drive transmission device according to another aspect of the present invention is two reduction portions that are attached at positions spaced apart from each other along the rotational axis direction of the first member among the first member and the second member that are rotatably connected to each other around the rotational axis and synchronously transmit the rotational force from the drive source to the second member, two bracket portions that are arranged to be spaced apart along the rotational axis direction and are attached to the second member, two flange portions that extend in a direction intersecting the rotational axis and have an overlapping region that overlaps the bracket portion when viewed in the direction along the rotational axis and connect the reduction portion and the bracket portion, and includes taking the reduction portion, the bracket portion, and the flange portion that are connected to each other as one set, In each of the overlapping regions of the groups, a restricting portion that extends in a direction along the rotation axis and restricts relative rotational movement around the rotation axis in the bracket portion and the flange portion, and a receiving portion that receives the restricting portion are provided. The arrangement of the flange portion and the bracket portion of one group is on the opposite side in the direction of the rotation axis with respect to the arrangement of the flange portion and the bracket portion of the other group. The receiving portion is a through-hole formed in the bracket portion and the flange portion and penetrating in a direction along the rotation axis. The restricting portion is a restricting pin that extends in a direction along the rotation axis and penetrates the through-holes of both groups.

[0018] With such a configuration, the second member can be rotationally driven with respect to the first member via the reduction portion, the flange portion, and the bracket portion by the rotational driving force of the drive source. Moreover, between the flange portion and the bracket portion, it is possible to perform position regulation and attitude regulation around the rotation axis while allowing dimensional errors in the direction of the rotation axis by the restricting portion and the receiving portion. At the same time, the relative movement in the direction along the rotation axis between the bracket portion and the flange portion can be allowed based on the separation distance of the bracket portion in the direction along the rotation axis by the restricting portion and the receiving portion. Thereby, when assembling and connecting the second member and the first member, the assembly can be performed only by aligning the positions of the through-holes as the receiving portions of the bracket portion and the flange portion and inserting and fixing the restricting pin as the restricting portion. Therefore, when assembling and connecting the second member and the first member, it is possible to easily assemble without worrying about dimensional errors in the direction of the rotation axis and without worrying about the assembly attitude of the second member and the first member, and it is possible to improve workability. Thereby, when replacing the second member with respect to the first member, it is possible to easily assemble without worrying about dimensional errors in the direction of the rotation axis and without worrying about the assembly attitude of the second member and the first member, and it is possible to shorten the working time of the replacement work and improve efficiency.

[0019] (9) A construction machine according to another aspect of the present invention includes a first member having a drive source that generates a rotational force, and a second member rotatably connected about a rotation axis to the first member via a drive transmission device, and is provided with The drive transmission device includes a speed reduction unit that is located close to the second member in the first member and transmits the rotational force from the drive source to the second member, at least two bracket portions that are located close to the first member in the second member and are spaced apart along the rotation axis direction, a flange portion that extends in a direction intersecting the rotation axis and has an overlapping region that overlaps the bracket portion when viewed in the direction along the rotation axis, and connects the speed reduction unit and the bracket portion, is provided with In the overlapping region, a restricting portion that extends in the direction along the rotation axis and restricts relative rotational movement about the rotation axis in the bracket portion and the flange portion, and a receiving portion that receives the restricting portion are provided, The restricting portion and the receiving portion allow relative movement in the direction along the rotation axis in the bracket portion and the flange portion based on the separation distance of the bracket portion in the direction along the rotation axis.

[0020] According to the above configuration, rotational driving by the speed reduction unit is enabled, and the assembly workability and replacement workability can be improved. Thereby, a construction machine to which a rotary electric actuator is applied can be easily provided.

Effect of the Invention

[0021] According to the present invention, even when it is not possible to change the unfortunate clearance dimension of the rotational eccentricity, a drive transmission device that can be assembled without performing adjustment work on this mounting clearance and a construction machine equipped with this drive transmission device can be easily provided.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Mode for Carrying Out the Invention

[0023] Hereinafter, a first embodiment of a drive transmission device and a construction machine according to the present invention will be described with reference to the drawings.

[0024] <Excavator> FIG. 1 is a schematic configuration diagram of an excavator 100 according to an embodiment of the construction machine of the present invention as viewed from the side. In the following description, the front direction in which an operator (not shown) who operates the excavator 100 faces is simply referred to as the front. The opposite side to the front direction in the horizontal direction is referred to as the rear. The vertical direction in the state where the excavator 100 is placed on the road surface is simply referred to as the vertical direction. The direction orthogonal to the front-rear direction and the vertical direction is referred to as the vehicle width direction. FIG. 1 shows the state of the excavator 100 as viewed from the vehicle width direction.

[0025] As shown in FIG. 1, the excavator 100 includes a self-propelled traveling body 101, a revolving body 103 provided on the upper part of the traveling body 101 via a slewing mechanism 102 and revolving with respect to the traveling body 101, and a working unit 104 provided on the revolving body 103. The traveling body 101 and the slewing mechanism 102 are driven by, for example, an electric motor with a speed reducer (not shown). The traveling body 101 includes, for example, two crawlers 105 arranged in the vehicle width direction. However, the present invention is not limited to this, and wheels or the like may be used instead of the crawlers 105.

[0026] The working unit 104 includes a boom 108 and an arm 109 that are long in the front-rear direction, and a bucket 110. The boom 108, the arm 109, and the bucket 110 are each rotatably connected via a drive transmission device 1. Specifically, one end in the longitudinal direction of the boom 108 (in FIG. 1, one end in the longitudinal direction of this boom 108 and the drive transmission device 1 provided at this one end in the longitudinal direction are not shown) is rotatably connected to the revolving body 103 via the drive transmission device 1. One end 109a in the longitudinal direction of the arm 109 is rotatably connected to the other end 108a in the longitudinal direction of the boom 108 via the drive transmission device 1. The bucket 110 is rotatably connected to the other end 109b in the longitudinal direction of the arm 109 via the drive transmission device 1. All the drive transmission devices 1 provided in each part have the same configuration. Therefore, in the following description, only the drive transmission device 1 that connects the bucket 110 to the other end 109b in the longitudinal direction of the arm 109 will be described, and the description of the other drive transmission devices 1 will be omitted.

[0027] FIG. 2 is a schematic configuration diagram showing details of the connection portion between the arm 109 and the bucket 110. In FIG. 2, for ease of explanation, the arm 109 and the bucket 110 excluding the bracket 112 are shown by a two-dot chain line. As shown in FIG. 2, a motor (a drive source in the claims, an example of the motor) 120 is built in the arm 109, and the rotational force of this motor 120 is transmitted to the bucket 110 via the drive transmission device 1. That is, the arm 109 is an example of the first member in the claims. The bucket 110 is an example of the second member in the claims.

[0028] The motor 120 is a so-called electric motor that is driven by being supplied with electric power from an external power source (battery) provided in the rotating body 103, for example. As the motor 120, various motors that are driven by being supplied with electric power, such as a so-called brushed motor or a brushless motor, can be adopted. The motor 120 is arranged with a motor shaft 120a that rotates around a first rotation axis C1 facing the bucket 110 side. The first rotation axis C1 of the motor shaft 120a and the longitudinal direction of the arm 109 coincide.

[0029] [First Embodiment] <Drive Transmission Device> The drive transmission device 1 is arranged on a second rotation axis (an example of the rotation axis in the claims) C2 of the bucket 110 with respect to the arm 109. By being connected to the arm 109 via the drive transmission device 1, the bucket 110 rotates around the second rotation axis C2.

[0030] The drive transmission device 1 includes a differential device 2 housed in a housing 4 fixed to the other end 109b in the longitudinal direction of the arm 109, two reduction units 3A and 3B (a first reduction unit 3A and a second reduction unit 3B) arranged on both sides with the differential device 2 interposed therebetween and each connected to the differential device 2, flange portions 111 connected on both sides on the second rotation axis C2 with the reduction units 3A and 3B interposed therebetween, a regulating pin (regulating portion) 113 passing through the flange portion 111 at a position close to the bucket 110 along the second rotation axis C2, and an attachment bracket (bracket portion) 112 of the bucket 110 penetrated by the regulating pin 113.

[0031] The rotation axes of the two reduction units 3A and 3B are parallel to the second rotation axis C2. In the following description, the direction parallel to the second rotation axis C2 may be referred to as the axial direction, the direction around the second rotation axis C2 may be referred to as the circumferential direction, and the direction orthogonal to the axial direction and the circumferential direction may be referred to as the radial direction. By fixing one set of the flange portion 111, the regulating pin 113, and the attachment bracket 112 to the reduction unit 3A and the other set of the flange portion 111, the regulating pin 113, and the attachment bracket 112 to the reduction unit 3B, the bucket 110 rotates around the second rotation axis C2 with respect to the arm 109.

[0032] FIG. 3 is a schematic configuration diagram showing an overlapping region when the connection portion between the arm 109 and the bucket 110 is viewed in the direction along the second rotation axis C2. As shown in FIG. 3, the drive transmission device 1 has an overlapping region 130 where the flange portion 111 and the bracket portion 112 overlap each other at a position between the arm 109 and the bucket 110 when viewed in the direction along the second rotation axis C2.

[0033] In the flange portion 111 in the overlapping region 130, two through holes 111c penetrating in the direction along the second rotation axis C2 are provided. In the attachment bracket 112 in the overlapping region 130, two through holes 112c penetrating in the direction along the second rotation axis C2 are provided. The through hole 111c of the flange portion 111 and the through hole 112c of the mounting bracket 112 are formed at positions that coincide with each other when viewed in the direction along the second rotation axis C2. The through hole 111c of the flange portion 111 and the through hole 112c of the mounting bracket 112 are each penetrated by a regulating pin 113.

[0034] The regulating pin 113 is configured as a regulating portion that extends in the direction along the second rotation axis C2 and regulates the relative rotational movement around the second rotation axis C2 in the flange portion 111 and the mounting bracket 112. The through hole 111c and the through hole 112c are configured as receiving portions for receiving the regulating pin 113.

[0035] In the present embodiment, a plurality of sets, specifically two sets, of the through holes 111c and 112c as receiving portions and the regulating pin 113 as a regulating portion are arranged around the rotation axis. The number of sets of the receiving portion and the regulating portion is not limited to two sets, and more sets can also be provided. The sets of the receiving portion and the regulating portion are arranged spaced apart from each other in the circumferential direction of the second rotation axis C2. The sets of the receiving portion and the regulating portion can also be arranged spaced apart from each other in the axial direction of the second rotation axis C2.

[0036] The through holes 111c and 112c as receiving portions have a round cross-sectional contour in a direction intersecting the second rotation axis C2, as shown in FIG. 3. The regulating pin 113 has a substantially circular cross-sectional contour that is round in a direction intersecting the second rotation axis C2, as shown in FIG. 3. The cross-sectional shapes of the regulating pin 113 and the through holes 111c and 112c are formed to be substantially the same. Note that the regulating pin 113 will be described later.

[0037] FIG. 4 is a schematic configuration diagram of the differential device 2. The differential device 2 is connected to the motor shaft 120a via a transmission shaft 121. The differential device 2 is provided at the end of the transmission shaft 121 on the side opposite to the motor 120, and includes a first bevel gear 71 that rotates about a first rotation axis C1, a second bevel gear 72 that meshes with the first bevel gear 71, a differential case 73 fixed to the second bevel gear 72, a pinion gear 74 rotatably supported in a protruding manner within the differential case 73, and a pair of side gears 75a, 75b (a first side gear 75a and a second side gear 75b) that mesh with the pinion gear 74.

[0038] The second bevel gear 72 rotates about a second rotation axis C2. An insertion hole 72a through which a first operating output shaft 76a described later passes is formed at the radial center of the second bevel gear 72. The differential case 73 is fixed to the end face 72b of the second bevel gear 72 on the first bevel gear 71 side. The differential case 73 is formed in a rectangular frame shape and has two side faces 73a, 73b (a first side face 73a and a second side face 73b) arranged axially opposite to each other, and two side faces 73c, 73d (a third side face 73c and a fourth side face 73d) arranged opposite to each other with the direction orthogonal to the plane direction of these side faces 73a, 73b as the plane direction. Among the four side faces 73a to 73d, the outside of the first side face 73a is fixed to the end face 72b on the first bevel gear 71 side.

[0039] Also, the pinion gear 74 is provided on the third side face 73c and the fourth side face 73d. The pinion gear 74 is rotatably supported on each of the side faces 73c, 73d with a third rotation axis C3 orthogonal to the axial direction as the axis, and rotates integrally with the differential case 73 about the second rotation axis C2.

[0040] A pair of side gears 75a and 75b are arranged on both sides with the pinion gear 74 in between. That is, among the pair of side gears 75a and 75b, the first side gear 75a is coaxially arranged with the second rotation axis C2 inside the first side surface 73a of the differential case 73. Among the pair of side gears 75a and 75b, the second side gear 75b is coaxially arranged with the second rotation axis C2 inside the second side surface 73b of the differential case 73.

[0041] One end of the first operation output shaft 76a is provided on the end surface 75c on the first side surface 73a side of the first side gear 75a. The first operation output shaft 76a is arranged coaxially with the second rotation axis C2. The other end of the first operation output shaft 76a protrudes through the insertion hole 73e formed in the first side surface 73a and the insertion hole 72a of the second bevel gear 72. That is, the first side gear 75a is rotatably supported on the first side surface 73a of the differential case 73. On the other end of the first operation output shaft 76a, a tooth portion 76c that meshes with the first reduction portion 3A of the two reduction portions 3A and 3B is formed on the outer peripheral surface.

[0042] One end of the second operation output shaft 76b is provided on the end surface 75d on the second side surface 73b side of the second side gear 75b. The second operation output shaft 76b is arranged coaxially with the second rotation axis C2. The other end of the second operation output shaft 76b protrudes through the insertion hole 73e formed in the second side surface 73b. That is, the second side gear 75b is rotatably supported on the second side surface 73b of the differential case 73. On the other end of the second operation output shaft 76b, a tooth portion 76d that meshes with the second reduction portion 3B of the two reduction portions 3A and 3B is formed on the outer peripheral surface. In this way, each operation output shaft 76a and 76b constitutes a part of each reduction portion 3A and 3B connected to the differential device 2.

[0043] <Reduction portion> FIG. 5 is a schematic configuration diagram of the first reduction portion 3A. The configurations of the two speed reduction units 3A and 3B are the same, and they are arranged symmetrically with respect to the third axis of rotation C3. Therefore, in the following description, basically only the first speed reduction unit 3A will be described, and the second speed reduction unit 3B will be described as necessary. As shown in FIG. 5, the first speed reduction unit 3A includes a cylindrical case 11, a carrier 14 disposed inside the case 11 in the radial direction, and a reduction output unit 18 that rotates the carrier 14 at a rotational speed reduced at a constant ratio with respect to the rotational speed of the first operation output shaft 76a.

[0044] <Case> An outer flange portion 11a that projects radially outward is integrally formed on the outer peripheral surface of the case 11. The outer flange portion 11a has a quadrangular cross section along the axial direction. The housing 4 is disposed on the end surface 11b of the outer flange portion 11a on the differential device 2 side (the left side in FIG. 4). The housing 4 is fastened and fixed to the outer flange portion 11a by bolts 5. 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.

[0045] <Carrier> The carrier 14 is rotatably supported by the case 11 by a pair of main bearings (an example of the bearing in the claims) 26 arranged at intervals in the axial direction. The main bearing 26 is, for example, an angular ball bearing. The carrier 14 is arranged coaxially with the case 11 and the second axis of rotation C2.

[0046] It includes an end plate portion 30 disposed on the side opposite to the differential device 2, and a substrate portion 32 integrally formed with the substrate portion 32 and three cylindrical column portions 33 protruding from the substrate portion 32 toward the end plate portion 30. The column portions 33 are arranged at equal intervals in the circumferential direction. An end plate portion 30 is arranged at the tip 33a of the column portion 33. A flange portion 111 is arranged on one surface 30a of the end plate portion 30 opposite to the substrate portion 32. Then, both the end plate portion 30 and the flange portion 111 are fastened and fixed to the column portion 33 by bolts 34. In this state, a space having a constant width in the axial direction is formed between the substrate portion 32 and the end plate portion 30.

[0047] A pin 36 for positioning the end plate portion 30 with respect to the substrate portion 32 is provided slightly radially inward of the bolt 34 of the column portion 33. The pin 36 is arranged so as to straddle the column portion 33 and the end plate portion 30. Note that the column portion 33 does not necessarily need to be integrally formed with the substrate portion 32. In this case, the column portion 33 is fastened to the substrate portion 32. Also, the column portion 33 is not limited to a cylindrical shape. It is sufficient that a space having a constant width in the axial direction is formed between the substrate portion 32 and the end plate portion 30 by the column portion 33.

[0048] Further, a plurality (for example, three in this embodiment) of through holes 30c and 32b into which a crankshaft 46 (to be described later) of the speed reduction output portion 18 is inserted are formed in the end plate portion 30 and the substrate portion 32, respectively. The through holes 30c and 32b are arranged at equal intervals in the circumferential direction.

[0049] <Speed reduction output portion> The speed reduction output portion 18 includes a plurality (for example, three in this embodiment) of transmission gears 44 meshed with the tooth portion 76c of the first operating output shaft 76a, a plurality (for example, three in this embodiment) of crankshafts 46 having one end fixed to the transmission gear 44, and a first external gear (an example of the external gear member in the claims) 48a and a second external gear (an example of the external gear member in the claims) 48b that swing and rotate as the crankshaft 46 rotates.

[0050] Since the transmission gear 44 is fixed to one end of the crankshaft 46, the rotation of the first operating output shaft 76a is transmitted to the crankshaft 46 via the transmission gear 44. The crankshaft 46 is arranged along the axial direction. That is, the crankshaft 46 rotates about a crank rotation axis C4 (an example of another rotation axis in the claims) parallel to the second rotation axis C2. The crankshaft 46 is rotatably supported by the end plate portion 30 via the first crank bearing 51. Further, the crankshaft 46 is rotatably supported by the substrate portion 32 via the second crank bearing 52. The first crank bearing 51 and the second crank bearing 52 are, for example, tapered roller bearings.

[0051] At the axial center of the crankshaft 46, a first eccentric portion 46a and a second eccentric portion 46b that are eccentric from the axis of the crankshaft 46 are formed. The first eccentric portion 46a and the second eccentric portion 46b are arranged 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. Further, the first eccentric portion 46a and the second eccentric portion 46b are out of phase with each other. Such a crankshaft 46 is inserted into the through holes 30c and 32b of the end plate portion 30 and the substrate portion 32. That is, the crankshaft 46 is also arranged at equal intervals in the circumferential direction like the through holes 30c and 32b.

[0052] 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 plurality of rollers 56 and a cage 57 that holds the plurality of rollers 56. Since the second roller bearing 55b has the same configuration as the first roller bearing 55a, a detailed description thereof is omitted. With each roller bearing 55a, 55b, the first external gear 48a and the second external gear 48b are oscillated and rotated as the crankshaft 46 rotates.

[0053] The first external gear 48a and the second external gear 48b are arranged in the space between the substrate 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. In the first external gear 48a and the second external gear 48b, a first through hole 48c into which the column portion 33 is inserted and a second through hole 48d into which the eccentric portions 46a, 46b of the crankshaft 46 are inserted are formed.

[0054] The first eccentric portion 46a of the crankshaft 46 and the first roller bearing 55a are inserted into the second through hole 48d 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 second through hole 48d of the second external gear 48b. Accordingly, as the first eccentric portion 46a and the second eccentric portion 46b swing and rotate with the rotation of the crankshaft 46, the first external gear 48a and the second external gear 48b are swing-rotated while meshing with the internal teeth 24 of the case 11.

[0055] <Operation of the drive transmission device> Next, the operation of the drive transmission device 1 will be described. When the motor 120 provided on the arm 109 is driven, the rotation of the motor shaft 120a is transmitted to the first bevel gear 71 of the drive transmission device 1 via the transmission shaft 121. Then, the second bevel gear 72 meshing with the first bevel gear 71 is rotated. Further, the differential case 73 fixed to the second bevel gear 72 is rotated. Then, the pinion gear 74 is rotated about the second rotation axis C2. Accordingly, a pair of side gears 75a, 75b meshing with the pinion gear 74 are rotated.

[0056] Of the pair of side gears 75a, 75b, the rotation of the first side gear 75a is transmitted to the first reduction unit 3A via the first operation output shaft 76a. Of the pair of side gears 75a, 75b, the rotation of the second side gear 75b is transmitted to the second reduction unit 3B via the second operation output shaft 76b. Hereinafter, the operation of the first reduction unit 3A among the two reduction units 3A, 3B will be described.

[0057] The first reduction unit 3A causes the transmission gear 44 meshing with the first operating output shaft 76a to rotate due to the rotation of the first operating output shaft 76a. As a result, the crankshaft 46 is rotated integrally with the transmission gear 44 about the crank rotation axis C4. When the crankshaft 46 is rotated, the first external gear 48a rotates while meshing with the internal teeth 24 as the first eccentric portion 46a swings. Also, the second external gear 48b rotates while meshing with the internal teeth 24 as the second eccentric portion 46b swings. That is, the crankshaft 46 rotates about the crank rotation axis C4 and revolves about the second rotation axis C2.

[0058] In the present embodiment, the column portion 33 passing through the first through holes 48c of both the external gears 48a and 48b is fixed in a fixed position together with the substrate portion 32. As a result, the carrier 14 rotates about the second rotation axis C2 with respect to the case 11 at a rotational speed reduced from the first operating output shaft 76a. One end 109b in the longitudinal direction of the arm 109 is fixed to the case 11 via the housing 4. A flange portion 111 is fixed to the end plate portion 30 of the carrier 14. A regulating pin 113 passes through the through hole 111c of the flange portion 111, and this regulating pin 113 also passes through the through hole 112c of the mounting bracket 112.

[0059] Also, two sets of the through hole 111c, the through hole 112c, and the regulating pin 113 are provided at intervals about the second rotation axis C2. Therefore, by driving the motor 120 provided on the arm 109, the bucket 110 rotates about the second rotation axis C2 with respect to the arm 109.

[0060] Here, in the present embodiment, the drive transmission device 1 includes two reduction units 3A and 3B that decelerate and output the rotation of the motor 120. The two reduction units 3A and 3B are fixed in arrangement in the direction along the second rotation axis C2.

[0061] <Assembly process of the drive transmission device> Next, the dimensions and the assembly process of the drive transmission device 1 will be described. FIG. 6 is an exploded configuration diagram for explaining the dimensions and assembly process of the drive transmission device 1. In the drive transmission device 1, the separation distance D112 of the outer surface 112b of the mounting bracket 112 in the direction along the second rotation axis C2 is set to be approximately the same as or smaller than the separation distance D111a of the opposing surface 111a of the flange portion 111 in the direction along the second rotation axis C2. By setting the separation distance D111a and the separation distance D112 as described above, when connecting the arm 109 and the bucket 110, the mounting bracket 112 can be easily inserted between the flange portions 111.

[0062] In the assembly process of the drive transmission device 1, as shown by the arrow As1 in FIG. 6, the arm 109 and the bucket 110 are brought close to each other, and the mounting bracket 112 is easily inserted between the flange portions 111. At this time, when viewed in the direction along the second rotation axis C2, the arm 109 and the bucket 110 are brought close to each other until the two sets of through holes 111c and 112c coincide with each other. At this time, the axes of the two sets of through holes 111c and 112c are made to coincide.

[0063] Next, as shown by the arrow As2 in FIG. 6, the regulating pin 13 is passed through the two sets of through holes 111c and 112c. Further, the regulating pin 13 is fixed so as not to move in the direction along the second rotation axis C2, and the assembly of the drive transmission device 1 is completed.

[0064] In this way, in the assembly process of the drive transmission device 1, although the separation dimensions of the flange portion 111 and the mounting bracket 112 are fixed in the direction of the rotation axis C2, by connecting the flange portion 111 and the mounting bracket 112 with the regulating pins 113, the bucket 110 can be connected in a state where it can be rotationally driven by the speed reduction units 3A and 3B. Moreover, at this time, by connecting with two regulating pins 113, the bucket 110 can be connected to the flange portion 111 so as not to rotate around the rotation axis C2.

[0065] FIG. 7 is an exploded configuration diagram showing the assembly process of the regulating pin, flange portion, and mounting bracket in the drive transmission device 1. The regulating pin 13 includes a uniform cylindrical portion 113a that substantially matches the diameter dimensions of the through holes 111c and 112c, an enlarged diameter portion 113b provided at one end of the cylindrical portion 113a, and a fixed receiving portion 113e provided at the other end of the cylindrical portion 113a. The fixed receiving portion 113e has a reduced diameter compared to the cylindrical portion 113a. Further, the regulating pin 13 includes a fixing portion 113f that is fitted into the fixed receiving portion 113e and restricts the regulating pin 113 from moving in the direction of the second rotation axis C2 and coming out of the through holes 111c and 112c. The fixing portion 113f can be in the shape of a C-ring, a U-shaped member corresponding to the fixed receiving portion 113e, or a plate body having a notch.

[0066] Alternatively, a hole or aperture having an axis in the radial direction of the cylindrical portion 113a can be formed as the fixed receiving portion 113e, and the fixing portion 113f can be a fixing pin inserted into these. FIG. 8 is an exploded configuration diagram showing another example in the assembly process of the regulating pin, flange portion, and mounting bracket in the drive transmission device 1. Furthermore, as shown in FIG. 8, the regulating pin 13 can be configured such that a male screw portion (fixed receiving portion) 113g is provided at the other end of the cylindrical portion 113a and is fixed by a nut (fixing portion) 113h.

[0067] The fixing by the regulating pin 113 in the assembly process of the drive transmission device 1 will be described. In the final step of assembling the drive transmission device 1, as shown by the arrow As2 in FIGS. 7 and 8, when inserting the regulating pin 113 into the through holes 111c and 112c in the direction of the second rotation axis C2, the regulating pin 113 is passed through the through holes 111c and 112c such that the member 113c is positioned in between the flange portion 111 and the mounting bracket 112. Next, as shown by arrow As3 in FIGS. 7 and 8, the other end of the cylindrical portion 113a is fixed by the fixing portion 113f or the nut (fixing portion) 113h so as not to move in the direction of the second rotation axis C2. One end of the cylindrical portion 113a is fixed by the enlarged diameter portion 113b having an enlarged diameter so as not to move in the direction of the second rotation axis C2.

[0068] FIG. 9 is an exploded configuration diagram showing another example in the assembly process of the regulating pin, the flange portion, and the mounting bracket in the drive transmission device 1. Furthermore, as shown in FIG. 9, taps 113j are formed on the end faces of the two regulating pins 113, and a plate body 113k as a fixing portion is simultaneously inserted into the taps 113j. Instead of the plate body 113k, a U-shaped fixture can also be used.

[0069] In the present embodiment, the flange portion 111 is connected from both outer sides in the direction of the second rotation axis C2 in the two reduction portions 3A and 3B, and the bucket 110 is connected by the mounting bracket 112 from both inner sides in the direction of the second rotation axis C2. Thus, the bucket 110 can be rotated by the two reduction portions 3A and 3B, and at the same time, dimensional errors can be absorbed between the flange portion 111 and the mounting bracket 112. Therefore, it is not necessary to prepare an extra spacer or the like in advance, and the drive transmission device 1 can be easily assembled with a simple configuration.

[0070] Hereinafter, a second embodiment of the drive transmission device and the construction machine according to the present invention will be described with reference to the drawings. FIG. 10 is a schematic configuration diagram showing the dimensions and the assembled state of the drive transmission device in the present embodiment. In the present embodiment, the difference from the above-described first embodiment is related to the mounting bracket (bracket portion). The same reference numerals are given to the corresponding configurations as those in the above-described first embodiment, and the description thereof is omitted.

[0071] In the present embodiment, as shown in FIG. 10, two attachment brackets 114 are formed on the bucket 110 so as to be spaced apart from each other in the direction of the second rotation axis C2. Here, the opposing surfaces 114a facing each other in the direction of the second rotation axis C2 are spaced apart by a separation distance D114 in the direction of the second rotation axis C2. This separation distance D114 is set to be larger than the separation distance D111b between the outer surfaces 111b of the two flange portions 111, unlike the first embodiment. According to the present embodiment, the two attachment brackets 114 are connected by the regulating pin 113 in a state of being located outside the two flange portions 111 in the direction of the second rotation axis C2.

[0072] In the present embodiment, the same effects as those of the above-described embodiment can be achieved.

[0073] Hereinafter, a third embodiment of the drive transmission device and the construction machine according to the present invention will be described with reference to the drawings. FIG. 11 is a schematic configuration diagram showing an assembled state of the drive transmission device in the present embodiment. In the present embodiment, what is different from the above-described first and second embodiments is the attachment bracket (bracket portion) and the regulating pin. For the configurations corresponding to the above-described first and second embodiments other than this, the same reference numerals are given and the description thereof is omitted.

[0074] In the present embodiment, as shown in FIG. 11, four attachment brackets 112 and 114 are formed on the bucket 110 so as to be spaced apart from each other in the direction of the second rotation axis C2. The two attachment brackets 112 are arranged to be located inside the two flange portions 111, similarly to the first embodiment. Also, the two attachment brackets 114 are arranged to be located outside the two flange portions 111, similarly to the second embodiment. Further, two regulating pins (regulating portions) 115 that are spaced apart from each other in the direction of the second rotation axis C2 are coaxial in the direction of the second rotation axis C2, and a total of four are provided and used for connecting the bucket 110.

[0075] One of the regulating pins (regulating part) 115 penetrates and is fixed to the attachment brackets 112 and 114 with respect to one flange part 111, and the other regulating pin 115 penetrates and is fixed to the attachment brackets 112 and 114 with respect to the other flange part 111. The regulating pin 115 has the same configuration as the regulating pin 113 except that it is shorter in length.

[0076] In this embodiment, the same effects as those of the above-described embodiments can be achieved. Further, in this embodiment, the regulating pin 115, which is a consumable, can be easily replaced, and since the regulating pin 115 does not penetrate the entire bucket 110, there is a possibility that the diameters of the speed reducers 3A and 3B can be increased. Further, in the case of a rotary actuator, the distance from the rotary shafts 76a and 76b to the bucket 110 inevitably becomes large, and when the distance from the rotation center to the tip of the bucket 110 is made the same as that in the case of a cylinder, the bucket 110 becomes small due to space constraints. However, with this structure, the effect that the bucket 110 can be extended into the empty space can be achieved.

[0077] Hereinafter, a fourth embodiment of the drive transmission device and the construction machine according to the present invention will be described with reference to the drawings. FIG. 12 is a schematic configuration diagram showing an assembly process in the drive transmission device in this embodiment. In this embodiment, the difference from the above-described third embodiment lies in one attachment bracket (bracket part), the regulating part, and the receiving part. The same reference numerals are given to the corresponding configurations as those in the above-described third embodiment, and the description thereof is omitted.

[0078] In this embodiment, as shown in FIG. 12, for one flange portion 111, attachment brackets 112 and 114 are arranged close to both sides in the direction of the second rotation axis C2, similar to the third embodiment. For the other flange portion 111, only one attachment bracket 116 is arranged outside in the direction of the second rotation axis C2. This attachment bracket 116 is arranged at a position equivalent to that of the attachment bracket 114 of the second embodiment in the direction of the second rotation axis C2.

[0079] On the attachment bracket 116, as a restricting portion, a convex portion 116a protruding and extending in the direction of the second rotation axis C2 is formed on the inner side in the direction of the second rotation axis C2, that is, on the surface facing the flange portion 111 in the assembled state. The convex portion 116a has, for example, the same diameter dimension as the above-described restricting pins 113 and 115. Also, the protruding dimension of the convex portion 116a in the direction of the second rotation axis C2 can be made smaller than the thickness of the flange portion 111.

[0080] On the other flange portion 111, a recess 116b is formed as a receiving portion on the outer surface in the direction of the second rotation axis C2. The recess 116b is formed to be able to receive the convex portion 116a. Note that through holes are not formed in the other flange portion 111 and the corresponding attachment bracket 116.

[0081] In the assembling process of the drive transmission device 1 in this embodiment, as shown by the arrow As1a in FIG. 12, the other flange portion 111 is brought close to the corresponding attachment bracket 116, and the convex portion (restricting portion) 116a is fitted into the recess (receiving portion) 116b. Next, as shown by the arrow As1b in FIG. 12, one flange portion 111 is inserted between the corresponding attachment bracket 112 and attachment bracket 114. At this time, alignment is performed so that the axes of the through hole 111c, the through hole 112c, and the through hole 114c coincide. Further, as shown by the arrow As2 in FIG. 12, the restricting pin 115 is inserted into and fixed to the through holes 111c, 112c, and 114c to complete the assembling process.

[0082] In this embodiment, the same effects as those of the above-described embodiments can be achieved. Further, in this embodiment, the base portion of the convex portion 116a is used as a bolt and is screwed to the attachment bracket 116 to form an exchangeable configuration, or the flange portion 111 in which the concave portion 116b is formed is made into an exchangeable configuration, so that the effect of facilitating the replacement of consumables can be achieved.

[0083] Hereinafter, a fifth embodiment of the drive transmission device and the construction machine according to the present invention will be described with reference to the drawings. FIG. 13 is a schematic configuration diagram showing an assembled state of the drive transmission device as viewed from the side in this embodiment. In this embodiment, the difference from the above-described first embodiment lies in the regulating portion and the receiving portion, and the same reference numerals are given to the configurations corresponding to those of the above-described first embodiment other than this, and the description thereof is omitted.

[0084] In this embodiment, as shown in FIG. 13, a rectangular (polygonal) through-hole 111Ac is formed in the flange portion 111, and correspondingly, a rectangular through-hole 112Ac is also formed in the attachment bracket 112 as a receiving portion. Note that one through-hole 111Ac and one through-hole 112Ac are formed respectively. Further, as a regulating portion, a regulating pin 113A having a rectangular cross-section is passed through the through-hole 111Ac and the through-hole 112Ac and fixed in the direction of the second rotation axis C2. Furthermore, instead of the bucket 110, another attachment 110A is fixed to the attachment bracket 112.

[0085] According to this embodiment, since both the through-holes 111Ac and 112Ac as the receiving portions are rectangular and the regulating pin 113A also has a rectangular cross-section, even if only one set of the receiving portion and the regulating portion is provided, the attachment 110A does not move around the second rotation axis C2 with respect to the speed reduction portions 3A and 3B.

[0086] In this embodiment, the same effects as those of the above-described embodiments can be achieved.

[0087] Furthermore, in the present invention, it is also possible to individually select each configuration in the above-described embodiments and implement them in combination respectively. Among the embodiments disclosed in this specification, those composed of a plurality of objects may integrate the plurality of objects, and conversely, those composed of one object may be divided into a plurality of objects. Whether integrated or not, it may be configured so as to achieve the object of the invention.

Explanation of Reference Numerals

[0088] 1... drive transmission device 3A, 3B... speed reduction unit 100... excavator (construction machine) 109... arm (first member) 110... bucket (second member) 111... flange portion 111c... through hole (receiving portion) 112, 114, 116... mounting bracket (bracket portion) 112c, 114c... through hole (receiving portion) 113, 115... regulating pin (regulating portion) 116a... convex portion (regulating portion) 116b... concave portion (receiving portion) 120... motor (driving source) 130... overlapping region C2... second axis of rotation (axis of rotation)

Claims

1. A speed reduction unit that is attached to the first member and transmits the rotational force from the drive source to a second member that is rotatably connected to the first member about a rotation axis; At least two bracket portions that are spaced apart from each other along the rotation axis direction on the second member; A flange portion that extends in a direction intersecting the rotation axis and has an overlapping region that overlaps the bracket portion when viewed in the direction along the rotation axis, and connects the speed reduction unit and the bracket portion; Comprising: In the overlapping region, a restricting portion that extends in the direction along the rotation axis and restricts the relative rotational movement about the rotation axis in the bracket portion and the flange portion, and a receiving portion that receives the restricting portion are provided. A drive transmission device.

2. A plurality of sets of the receiving portion and the restricting portion are arranged around the rotation axis; The receiving portion has a circular cross-sectional contour in the direction intersecting the rotation axis; The drive transmission device according to Claim 1.

3. One set of the receiving portion and the restricting portion is arranged around the rotation axis; The receiving portion has a polygonal cross-sectional contour in the direction intersecting the rotation axis; The drive transmission device according to Claim 1.

4. The restricting portion is a restricting pin that extends in the direction along the rotation axis; The receiving portion is a through hole formed in the bracket portion and the flange portion through which the restricting pin penetrates; The drive transmission device according to Claim 2 or 3.

5. At least two of the speed reduction units are arranged spaced apart from each other along the rotation axis direction on the first member; The flange portion is connected to each of the speed reduction units; In the rotation axis direction, the bracket portions spaced apart in the rotation axis direction are both located inside and sandwiched by the flange portion; The drive transmission device according to any one of Claims 1 to 4.

6. At least two of the speed reduction units are arranged spaced apart from each other along the rotation axis direction on the first member; The flange portion is connected to each of the speed reduction units; In the rotation axis direction, the bracket portions spaced apart in the rotation axis direction are both located outside the flange portion; The drive transmission device according to any one of Claims 1 to 4.

7. At least two of the speed reduction units are arranged spaced apart from each other along the rotation axis direction on the first member; The flange portion is connected to each of the speed reduction units; In the axial direction of the rotation axis, one of the flange portions is located inside and sandwiched between the bracket portions spaced apart in the axial direction of the rotation axis, and the restricting portion is a restricting pin extending in a direction along the rotation axis, the receiving portion is a through hole formed in the bracket portion and one of the flange portions and through which the restricting pin penetrates, The drive transmission device according to any one of claims 1 to 4.

8. Two reduction parts that are attached to positions separated from each other along the axial direction of the rotation axis of the first member and the second member that are rotatably connected to each other around the rotation axis, and that transmit the rotational force from the drive source to the second member synchronously, Two bracket parts that are arranged apart from each other along the axial direction of the rotation axis and are attached to the second member, Two flange parts that extend in a direction intersecting the rotation axis and have an overlapping area that overlaps the bracket part when viewed in the direction along the rotation axis, and that connect the reduction part and the bracket part, comprising Regarding the reduction part, the bracket part, and the flange part that are connected to each other as a set, in each set of the overlapping areas, a restricting part that extends in a direction along the rotation axis and restricts relative rotational movement around the rotation axis in the bracket part and the flange part, and a receiving part that receives the restricting part are provided, the arrangement of the flange part and the bracket part of one set is on the opposite side in the axial direction of the rotation axis with respect to the arrangement of the flange part and the bracket part of the other set, the receiving part is a through hole formed in the bracket part and the flange part and penetrating in the direction along the rotation axis, the restricting part is a restricting pin that extends in the direction along the rotation axis and penetrates the through holes of both sets, Drive transmission device.

9. A first member having a drive source that generates a rotational force, A second member that is rotatably connected around a rotation axis to the first member via a drive transmission device, comprising The drive transmission device a reduction part that is located close to the second member in the first member and transmits the rotational force from the drive source to the second member, at least two bracket parts that are located close to the first member in the second member and are arranged apart from each other along the axial direction of the rotation axis, A flange portion that extends in a direction intersecting the rotation axis and has an overlapping region that overlaps the bracket portion when viewed in the direction along the rotation axis, and connects the speed reduction portion and the bracket portion. Comprising: In the overlapping region, a restricting portion that extends in the direction along the rotation axis and restricts relative rotational movement around the rotation axis in the bracket portion and the flange portion, and a receiving portion that receives the restricting portion are provided. The restricting portion and the receiving portion allow relative movement in the direction along the rotation axis in the bracket portion and the flange portion based on the separation distance of the bracket portion in the direction along the rotation axis. Construction machine.

Images