CN114684602A

CN114684602A - Industrial robot

Info

Publication number: CN114684602A
Application number: CN202111613300.3A
Authority: CN
Inventors: 矢泽隆之; 荒川洋
Original assignee: Nidec Sankyo Corp
Current assignee: Nidec Instruments Corp
Priority date: 2020-12-28
Filing date: 2021-12-27
Publication date: 2022-07-01
Anticipated expiration: 2041-12-27
Also published as: KR102570784B1; KR20220094132A; JP2022104002A; CN114684602B; JP7496772B2

Abstract

An industrial robot is provided with a hand linearly reciprocating in a front-rear direction relative to an arm, wherein the arm is lightened and the rigidity and strength of the arm are ensured even if the moving distance of the hand is long and the arm is large and the weight of a conveying object loaded on the hand is heavy. In the arm (9) of the industrial robot, a flat plate member (28) having a length in the front-rear direction longer than that of the arm main body (27) is fixed to each of the lateral sides of the block-shaped arm main body (27). A flat plate member (29) fixed to a flat plate member (28) and arranged with the vertical direction as the thickness direction, flat plate members (30, 31) arranged with the vertical direction as the thickness direction and fixed to the flat plate member (28), and flat plate members (32) arranged with the horizontal direction as the thickness direction and fixed to the flat plate members (29-31) are arranged on both sides of the arm main body (27) in the front-rear direction.

Description

Industrial robot

Technical Field

The present invention relates to an industrial robot for conveying a conveyance target object.

Background

Conventionally, an industrial robot that transports a glass substrate in a vacuum is known (for example, see patent document 1). The industrial robot described in patent document 1 includes two hands for mounting glass substrates, two hand support members for fixing the hands, an arm for holding the two hand support members, and a main body portion for connecting the arm. The arm is formed in a substantially rectangular parallelepiped shape elongated in the front-rear direction. The hand support member is linearly movable back and forth in the front-rear direction with respect to the arm. The main body portion includes a cylindrical elevating member at a center portion of the fixing arm.

In the industrial robot described in patent document 1, an arm includes: an arm support which is formed into a hollow shape and is used as a support of the arm; cover parts forming the upper, lower, left, right and front and rear side surfaces of the arm; a motor accommodating member disposed in a center portion of the arm; and an upper cover fixed on the upper surface of the motor accommodating component. The arm support is provided with a right side plate part constituting the right side surface of the arm support, a left side plate part constituting the left side surface of the arm support, an upper side plate part constituting the upper side surface of the arm support, and a lower side plate part constituting the lower side surface of the arm support.

The motor housing member is formed in a box shape with an open upper surface. The motor accommodating part is fixed with the center of the arm support, and the motor accommodating part and the arm support form a framework of the arm. The motor accommodating part is fixed on the upper end surface of the lifting part. In the industrial robot described in patent document 1, gaps are formed between the motor housing member and the right side plate portion and between the motor housing member and the left side plate portion, and the right side plate portion and the left side plate portion are not fixed to the motor housing member.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2019-25587

Disclosure of Invention

Technical problem to be solved by the invention

In the case of an industrial robot that transports a transport object such as a glass substrate like the industrial robot described in patent document 1, depending on the application in which the industrial robot is used, the transport distance of the transport object placed on the hand may become long and the weight of the transport object may become heavy. If the transport distance of the object to be transported is long, the moving distance of the hand and the hand support member with respect to the arm is long, and therefore the length of the arm in the front-rear direction is long and the arm is large, and as a result, the weight of the arm may be heavy. Further, if the arm is enlarged and the weight of the conveyance object placed on the hand is increased, the rigidity and strength of the arm that movably holds the hand and the hand support member may not be ensured.

In the industrial robot described in patent document 1, since the frame of the arm is formed by the motor housing member and the arm support formed in a box shape, the arm can be reduced in weight even if the length of the arm in the front-rear direction is increased and the arm is increased in size. On the other hand, in the industrial robot described in patent document 1, since a gap is formed between the motor housing member and the right side plate portion and between the motor housing member and the left side plate portion, and the right side plate portion and the left side plate portion are not fixed to the motor housing member, when the arm is large in size and the weight of the object to be conveyed placed on the hand becomes heavy, there is a possibility that the rigidity and strength of the arm cannot be secured.

Accordingly, an object of the present invention is to provide an industrial robot including a hand on which a conveyance object is loaded and which linearly reciprocates in a front-rear direction with respect to an arm, wherein the arm can be made lightweight and the rigidity and strength of the arm can be ensured even if the movement distance of the hand with respect to the arm is increased and the arm is made large, and even if the weight of the conveyance object loaded on the hand is increased.

Technical scheme for solving technical problem

In order to solve the above-described problems, the present invention provides an industrial robot including: a hand on which a conveyance object is loaded; a hand support member that fixes a proximal end portion of a hand; an arm that holds the hand support member such that the hand support member can linearly reciprocate in a horizontal direction; a main body portion connecting the arm; and a drive mechanism that reciprocates the hand support member relative to the arm, wherein the main body portion includes a pivot shaft for fixing the arm and a pivot mechanism that pivots the pivot shaft, and wherein the arm includes: a block-shaped arm main body which forms the center of the arm and is fixed on the rotating shaft; a first flat plate member fixed to each of left and right side surfaces of the arm main body; and a plurality of second flat plate members arranged on both sides of the arm body in the front-rear direction, the first flat plate member having a thickness direction that coincides with the left-right direction, the first flat plate member having a length in the front-rear direction that is longer than a length in the front-rear direction of the arm body, a front end of the first flat plate member being arranged on a front side of the front end of the arm body, the arm including, as the plurality of second flat plate members: a plurality of third flat plate members arranged in a thickness direction from the top to the bottom and fixed to the first flat plate member; a plurality of fourth flat plate members arranged in the thickness direction of the front-rear direction and fixed to the first flat plate member; and a plurality of fifth plate members arranged with the thickness direction in the lateral direction and fixed to at least one of the third plate member and the fourth plate member.

In the industrial robot of the present invention, the arm includes a block-shaped arm body constituting a center portion of the arm, a flat plate-shaped first flat plate member fixed to each of lateral side surfaces of the arm body in the left-right direction, and a plurality of flat plate-shaped second flat plate members disposed on both sides of the arm body in the front-rear direction. Therefore, in the present invention, the portion of the arm other than the central portion may be constituted by a flat plate-like member. Therefore, in the present invention, even if the movement distance of the hand and the hand support member with respect to the arm becomes long and the arm becomes large, the weight of the arm can be reduced as compared with the case where the entire arm is configured by a block-shaped arm main body.

In the present invention, the arm body, which is formed in a block shape and has relatively high strength and rigidity, constitutes the center portion of the arm and is fixed to the pivot shaft. In the present invention, the first flat plate member having a length in the front-rear direction longer than that of the arm main body is fixed to each of the lateral sides of the block-shaped arm main body in the left-right direction, and a plurality of third flat plate members fixed to the first flat plate member and arranged with the vertical direction as the thickness direction, a plurality of fourth flat plate members arranged with the front-rear direction as the thickness direction and fixed to the first flat plate member, and a plurality of fifth flat plate members fixed to at least either one of the third flat plate member and the fourth flat plate member and arranged with the left-right direction as the thickness direction are arranged on both sides of the arm main body in the front-rear direction.

Therefore, in the present invention, even if the arm is enlarged in the front-rear direction and the weight of the conveyance object placed on the hand becomes heavy relative to the arm, the rigidity and strength of the arm can be ensured. That is, in the present invention, even if the arm is large in size and the weight of the conveyance object placed on the hand is heavy, the rigidity and strength of the arm can be ensured while reducing the weight of the arm.

In the present invention, it is preferable that the first flat plate member is disposed over the entire region in the front-rear direction of the arm. This improves the rigidity and strength of the arm.

In the present invention, it is preferable that the front end of the hand is separated from the body portion as the hand support member moves forward relative to the arm, and the arm body is fixed to the pivot shaft at a position rearward of a center of the arm body in the front-rear direction. This can improve the rigidity of the front portion of the arm with respect to the pivot shaft. Therefore, the arm can be prevented from being flexed about the pivot shaft when the hand and the hand support member move forward relative to the arm.

In the present invention, it is preferable that the arm main body is formed with a plurality of concave portions that are recessed from a lower surface of the arm main body toward an upper side, and a total area of the plurality of concave portions disposed at a position forward of a center in the front-rear direction of the arm main body is larger than a total area of the plurality of concave portions disposed at a position rearward of the center in the front-rear direction of the arm main body when viewed in the up-down direction. Accordingly, the weight of the arm body can be effectively reduced while ensuring the rigidity and strength of the portion located on the rear side of the center in the front-rear direction of the arm body (i.e., the portion of the arm body to which the pivot shaft is fixed).

In the present invention, it is preferable that the arm includes: a plurality of sixth flat plate members that are flat plate-shaped, that are disposed on both sides of the two first flat plate members in the left-right direction, that are disposed with the vertical direction as the thickness direction, and that are fixed to the first flat plate members; a plurality of seventh plate members which are flat plate-shaped, are arranged on both sides in the left-right direction of the two first plate members, are arranged with the front-rear direction being the thickness direction, and are fixed to the first plate members; and a plurality of eighth plate members that are flat plate-shaped, that are disposed on both sides of the two first plate members in the left-right direction, that are disposed with the left-right direction as the thickness direction, and that are fixed to at least one of the sixth plate member and the seventh plate member. Accordingly, even if the width of the arm in the left-right direction is increased (i.e., even if the arm is increased in size in the left-right direction), the arm can be reduced in weight while ensuring the rigidity and strength of the arm.

In the present invention, an industrial robot includes, for example: a first hand and a second hand as hands; a first hand support member as a hand support member for fixing a proximal end portion of the first hand; a second hand support member as a hand support member for fixing a proximal end portion of the second hand; a first driving mechanism as a driving mechanism for reciprocating the first hand support member with respect to the arm; a second driving mechanism as a driving mechanism for reciprocating the second hand support member with respect to the arm; a first guide mechanism for guiding the first hand support member in the front-rear direction; and a second guide mechanism for guiding the second hand support member in the front-rear direction, wherein the first guide mechanism is disposed on the upper surface side of the arm, and the second guide mechanism is disposed on both sides of the arm in the left-right direction. In this case, since the first guide mechanism is disposed on the upper surface side of the arm and the second guide mechanism is disposed on both sides of the arm in the left-right direction, the first guide mechanism and the second guide mechanism can be easily provided.

In the present invention, for example, the first guide mechanism includes four first guide rails whose longitudinal direction is the front-rear direction and a first guide block which engages with the first guide rails from above, the second guide mechanism includes four second guide rails whose longitudinal direction is the front-rear direction and a second guide block which engages with the second guide rails from outside in the left-right direction, two of the four second guide rails are disposed on the right side of the arm, and the remaining two second guide rails are disposed on the left side of the arm.

In this case, since the first guide mechanism includes four first guide rails, even if the weight of the conveyance object loaded on the first hand becomes heavy, the first guide rails and the first guide blocks can be provided in a relatively small size. Therefore, the first guide rail and the first guide block can be easily installed. In this case, since the second guide mechanism includes four second guide rails, even if the weight of the conveyance object loaded on the second hand becomes heavy, the second guide rails and the second guide blocks can be provided in a relatively small size. Therefore, the second guide rail and the second guide block can be easily installed.

In the present invention, it is preferable that the arm includes: a plurality of sixth flat plate members that are flat plate-shaped, that are disposed on both sides of the two first flat plate members in the left-right direction, that are disposed with the vertical direction as the thickness direction, and that are fixed to the first flat plate members; a plurality of seventh plate members which are flat plate-shaped, are arranged on both sides in the left-right direction of the two first plate members, are arranged with the front-rear direction being the thickness direction, and are fixed to the first plate members; and a plurality of eighth plate members which are flat plate-shaped, are disposed on both sides in the lateral direction of the two first plate members, are disposed with the lateral direction as the thickness direction, and are fixed to at least either one of the sixth plate member and the seventh plate member, wherein the height of the lateral inner portions of the two first plate members of the arm is lower than the height of the lateral outer portions of the two first plate members of the arm, and wherein a part of the first drive mechanism and the first guide mechanism are disposed on the inner side in the lateral direction of the upper end side portions of the two first plate members.

Accordingly, even if the width of the arm in the left-right direction is increased, the arm can be reduced in weight while ensuring the rigidity and strength of the arm. In addition, according to this configuration, even if the part of the first drive mechanism and the first guide mechanism are disposed on the upper surface side of the arm, the part of the first drive mechanism and the first guide mechanism can be prevented from protruding upward from the upper surface of the arm.

Effects of the invention

As described above, in the present invention, in the industrial robot including the hand on which the conveyance target object is loaded and which linearly reciprocates in the front-rear direction with respect to the arm, even if the movement distance of the hand with respect to the arm becomes long and the arm becomes large, and even if the weight of the conveyance target object loaded on the hand becomes heavy, the arm can be made lightweight, and the rigidity and strength of the arm can be ensured.

Drawings

Fig. 1 is a plan view of an industrial robot according to an embodiment of the present invention.

Fig. 2 is a side view of the industrial robot shown in fig. 1.

Fig. 3 is a rear view of the industrial robot shown in fig. 1.

Fig. 4 is a plan view for explaining the structure of the industrial robot shown in fig. 1.

Fig. 5 (a) is a plan view of the arm shown in fig. 4, and fig. 5 (B) is a side view of the arm shown in fig. 4.

Fig. 6 is a bottom view of the arm shown in fig. 5.

Fig. 7 (a) is a rear view of the arm shown in fig. 5, and fig. 7 (B) is a sectional view of the section E-E of fig. 5 (a).

Fig. 8 (a) is a plan view of the arm main body shown in fig. 5, and fig. 8 (B) is a sectional view of the F-F section of fig. 8 (a).

Fig. 9 is a bottom view of the arm body shown in fig. 8.

Fig. 10 is an enlarged view of a portion G of fig. 4.

Fig. 11 is a side view for explaining the configuration of the first driving mechanism and the first guide mechanism shown in fig. 10.

Fig. 12 is a side view for explaining the structure of the second driving mechanism and the second guide mechanism shown in fig. 10.

Fig. 13 is a rear view for explaining the structure of the first guide mechanism and the second guide mechanism shown in fig. 10.

Fig. 14 is a rear view for explaining the structure of the first drive mechanism, the second drive mechanism, the first guide mechanism, and the second guide mechanism shown in fig. 10.

(description of reference numerals)

1 … robot (industrial robot); 2 … workpiece (conveying object); 5 … hands (first hand); 6 … hands (second hand); 7 … hand support member (first hand support member); 8 … hand support member (second hand support member); 9 … arm; 10 … a body portion; 11 … rotating shaft; 12 … rotating mechanism; 17 … driving mechanism (first driving mechanism); an 18 … drive mechanism (second drive mechanism); 19 … guide means (first guide means); a 20 … guide mechanism (second guide mechanism); 27 … arm body; 27e … recess; 28 … flat plate member (first flat plate member); 29 … flat plate member (second flat plate member, third flat plate member); 30. 31 … flat plate member (second flat plate member, fourth flat plate member); 32 … flat plate member (second flat plate member, fifth flat plate member); 34 … flat plate member (sixth flat plate member); 35 … flat plate member (seventh flat plate member); 36 … flat plate member (eighth flat plate member); 76 … guide rail (first guide rail); 77 … guide block (first guide block); 80 … guide rail (second guide rail); 81 … guide block (second guide block); x … front-to-back direction; y … left and right direction.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

(approximate Structure of Industrial robot)

Fig. 1 is a plan view of an industrial robot 1 according to an embodiment of the present invention. Fig. 2 is a side view of the industrial robot 1 shown in fig. 1. Fig. 3 is a rear view of the industrial robot 1 shown in fig. 1. Fig. 4 is a plan view for explaining the structure of the industrial robot 1 shown in fig. 1.

The industrial robot 1 (hereinafter referred to as "robot 1") of the present embodiment is a robot for conveying a conveyance target 2 (hereinafter referred to as "workpiece 2"). The robot 1 of the present embodiment conveys the workpiece 2 in vacuum. The weight of the workpiece 2 conveyed by the robot 1 is relatively heavy. For example, the weight of the workpiece 2 is about 270 kg. The workpiece 2 is formed in a rectangular flat plate shape.

The robot 1 includes: two hands 5, 6 carrying a workpiece 2; a hand support member 7 (see fig. 13) for fixing the proximal end of the hand 5; a hand support member 8 for fixing the base end portion of the hand 6; an arm 9 for holding the hand support members 7 and 8; and a main body portion 10 of the connecting arm 9. In the present embodiment, the hand 5 is a first hand, the hand 6 is a second hand, the hand support member 7 is a first hand support member, and the hand support member 8 is a second hand support member.

The main body 10 includes a pivot shaft 11 for fixing the arm 9, a pivot mechanism 12 for pivoting the pivot shaft 11, a lifting mechanism for lifting and lowering the pivot shaft 11 and the pivot mechanism 12, and a housing 13 for housing these components. The rotating shaft 11 is formed in an elongated cylindrical shape. The rotating shaft 11 is disposed so that the axial direction of the rotating shaft 11 coincides with the vertical direction, and is rotatable in the vertical direction as the rotational axial direction. The turning mechanism 12 includes, for example, a motor for turning the turning shaft 11, and a pulley and a belt for transmitting power of the motor to the turning shaft 11. The case 13 is formed in a substantially bottomed cylindrical shape. A flange 14 formed in a disc shape is fixed to an upper end of the housing 13. The flange 14 is formed with a through hole in which the upper end portion of the rotating shaft 11 is disposed.

The hands 5 and 6, the hand support members 7 and 8, and the arm 9 are disposed above the main body 10. As described above, the robot 1 conveys the workpiece 2 in vacuum. In the present embodiment, the portion of the robot 1 above the lower end surface of the flange 14 is disposed in the vacuum region VR, and the hands 5 and 6, the hand support members 7 and 8, and the arm 9 are disposed in the vacuum chamber (in vacuum). On the other hand, a portion of the robot 1 below the lower end surface of the flange 14 is disposed in the air region AR (in the air).

The arm 9 holds the hand support members 7, 8 so that the hand support members 7, 8 can linearly reciprocate in the horizontal direction. Specifically, the arm 9 holds the hand support members 7, 8 such that the hand support member 7 and the hand support member 8 can linearly reciprocate in the same direction in the horizontal direction (i.e., the hand 5 and the hand 6 can linearly reciprocate in the same direction in the horizontal direction). In the present embodiment, the movement distance of the hand support members 7 and 8 with respect to the arm 9 is relatively long. For example, the movement distance of the hand support members 7, 8 with respect to the arm 9 is 4700 mm.

In the following description, the direction of reciprocation (X direction in fig. 1 and the like) of the hand support members 7 and 8 with respect to the arm 9 is referred to as "front-rear direction", and the Y direction in fig. 1 and the like orthogonal to the up-down direction (vertical direction) and the front-rear direction is referred to as "left-right direction". Further, one side in the front-rear direction, i.e., the X1 direction side in fig. 1 and the like, is referred to as the "front" side, the opposite side thereof, i.e., the X2 direction side in fig. 1 and the like, is referred to as the "rear" side, one side in the left-right direction, i.e., the Y1 direction side in fig. 1 and the like, is referred to as the "right" side, and the opposite side thereof, i.e., the Y2 direction side in fig. 1 and the like, is referred to as the "left" side.

The robot 1 includes: a drive mechanism 17 for reciprocating the hand support member 7 with respect to the arm 9; a drive mechanism 18 for reciprocating the hand support member 8 with respect to the arm 9; a guide mechanism 19 for guiding the hand support member 7 in the front-rear direction; and a guide mechanism 20 (see fig. 4) for guiding the hand support member 8 in the front-rear direction. The driving mechanism 17 of the present embodiment is a first driving mechanism, the driving mechanism 18 is a second driving mechanism, the guide mechanism 19 is a first guide mechanism, and the guide mechanism 20 is a second guide mechanism.

Further, the robot 1 includes: a link support member 21 fixed to the rear end of the arm 9; a link mechanism 22 having one end rotatably connected to the link support member 21 and the other end rotatably connected to the rear end of the hand 5; a link mechanism 23 having one end rotatably connected to the link support member 21 and the other end rotatably connected to the rear end of the hand 6; and a wire harness (cable) 24 that runs between the link support member 21 and the hands 5, 6 along the link mechanisms 22, 23.

(Structure of arm)

Fig. 5 (a) is a plan view of the arm 9 shown in fig. 4, and fig. 5 (B) is a side view of the arm 9 shown in fig. 4. Fig. 6 is a bottom view of the arm 9 shown in fig. 5. Fig. 7 (a) is a rear view of the arm 9 shown in fig. 5, and fig. 7 (B) is a sectional view of the section E-E of fig. 5 (a).

Fig. 8 (a) is a plan view of the arm main body 27 shown in fig. 5, and fig. 8 (B) is a sectional view of the F-F section of fig. 8 (a). Fig. 9 is a bottom view of the arm main body 27 shown in fig. 8.

The arm 9 is disposed below the hands 5 and 6. The arm 9 is formed in a substantially rectangular parallelepiped shape elongated in the front-rear direction. As described above, in the present embodiment, since the movement distance of the hand support members 7 and 8 with respect to the arm 9 is relatively long, the length of the arm 9 in the front-rear direction is relatively long. The arm 9 includes: a block-shaped arm main body 27 constituting a central portion of the arm 9; and a flat plate-like plate member 28 fixed to each of the left and right side surfaces of the arm main body 27.

Further, the arm 9 includes: a plurality of flat plate members 29 to 32 arranged on both sides of the arm main body 27 in the front-rear direction; a flat plate member 33 disposed on the rear side of the arm main body 27; a plurality of flat plate members 34 to 36 disposed on both sides of the two flat plate members 28 in the left-right direction; and a fixing member for connecting the arm main body 27 and the plate member 32. The arm 9 of the present embodiment is composed of an arm main body 27, plate members 28 to 36, a fixing member, and a plurality of bolts connecting these members.

The arm main body 27 is formed of an aluminum alloy. The arm main body 27 is formed by cutting a rectangular parallelepiped aluminum alloy. The arm main body 27 is formed in a rectangular parallelepiped shape elongated in the front-rear direction. The arm main body 27 is formed in a flat rectangular parallelepiped shape with a small thickness in the vertical direction. The left and right side surfaces of the arm main body 27 are planes perpendicular to the left-right direction. The front and rear side surfaces of the arm main body 27 are planes orthogonal to the front and rear direction, and the upper and lower surfaces of the arm main body 27 are planes orthogonal to the upper and lower direction. The length of the arm main body 27 in the front-rear direction is about 1/3-1/2 of the length of the arm 9 in the front-rear direction.

The arm main body 27 is fixed to the rotating shaft 11. Specifically, the center portion in the left-right direction of the arm main body 27 is fixed to the upper end surface of the pivot shaft 11. The arm body 27 is fixed to the pivot shaft 11 at a position rearward of the center of the arm body 27 in the front-rear direction. That is, a portion of the arm main body 27 on the rear side of the center in the front-rear direction is fixed to the pivot shaft 11. In the present embodiment, the arm main body 27 is fixed to the pivot shaft 11 at a position 1/5 approximately the length of the arm main body 27 in the front-rear direction from the rear side surface of the arm main body 27.

A through hole 27a penetrating the arm main body 27 in the vertical direction is formed at a position of the arm main body 27 where the pivot shaft 11 is fixed. The through hole 27a is formed in a circular shape centering on the axial center of the rotating shaft 11 formed in a cylindrical shape. As shown in fig. 8 (B), the height of the upper surfaces of both end portions 27B of the arm main body 27 in the front-rear direction is lower than the height of the upper surface of the central portion 27c of the arm main body 27 except for the end portions 27B. Specifically, the height of the upper surface of the end portion 27b is lower than the height of the upper surface of the central portion 27c by about the thickness of the plate member 29. In the central portion 27c, the height of the upper surfaces of the both end portions 27d in the left-right direction is slightly higher than the height of the upper surfaces of the portions of the central portion 27c other than the end portions 27 d.

A plurality of recesses 27e recessed upward are formed in the lower surface of the arm main body 27. As shown in fig. 8 (B), the recess 27e is recessed to the vicinity of the upper surface of the arm main body 27. As shown in fig. 9, when viewed in the vertical direction, the area of most of the recesses 27e disposed forward of the center of the arm main body 27 in the front-rear direction is larger than the area of the recesses 27e disposed rearward of the center of the arm main body 27 in the front-rear direction. Further, when viewed in the vertical direction, the total area of the plurality of concave portions 27e arranged on the front side of the center in the front-rear direction of the arm main body 27 is larger than the total area of the plurality of concave portions 27e arranged on the rear side of the center in the front-rear direction of the arm main body 27. That is, the density of the portion located forward of the center in the front-rear direction of the arm main body 27 is lower than the density of the portion located rearward of the center in the front-rear direction of the arm main body 27.

The plate members 28 to 36 are formed of an aluminum alloy. The thicknesses of the plate members 28 to 36 are substantially equal to each other. The flat plate member 28 is formed in a rectangular flat plate shape elongated in the front-rear direction. The thickness direction of the flat plate member 28 coincides with the left-right direction. The length of the plate member 28 in the front-rear direction is longer than the length of the arm main body 27 in the front-rear direction. In the present embodiment, the length of the plate member 28 in the front-rear direction is about 2 to 3 times the length of the arm main body 27 in the front-rear direction. Further, the height (the width in the vertical direction) of the plate member 28 is higher than the height of the arm main body 27. In the present embodiment, the height of the plate member 28 is about 1.5 times the height of the arm main body 27.

The plate member 28 is fixed to each of the lateral side surfaces of the arm main body 27 by a plurality of bolts, and is directly fixed to the lateral side surfaces of the arm main body 27. The center portion in the front-rear direction of the flat plate member 28 is fixed to the lateral side surface of the arm main body 27, the front end surface of the flat plate member 28 is disposed at a position forward of the front surface of the arm main body 27, and the rear end surface of the flat plate member 28 is disposed at a position rearward of the rear surface of the arm main body 27.

That is, the front end of the plate member 28 is disposed on the front side of the front end of the arm main body 27, and the rear end of the plate member 28 is disposed on the rear side of the rear end of the arm main body 27. The lower end surface of the plate member 28 is disposed at the same position as the lower surface of the arm main body 27 in the vertical direction. The upper end surface of the plate member 28 is disposed above the upper surface of the arm main body 27. The flat plate member 28 is disposed over the entire region in the front-rear direction of the arm 9. That is, the plate member 28 constitutes a part of the arm 9 in the entire region in the front-rear direction of the arm 9.

The flat plate member 29 is formed in a rectangular flat plate shape having a longitudinal direction in the front-rear direction. The thickness direction of the plate member 29 coincides with the vertical direction. The plate members 29 are disposed on both sides of the arm main body 27 in the front-rear direction. A rear end portion of the flat plate member 29 disposed on the front side of the arm main body 27 is fixed to an upper surface of the front end portion 27b of the arm main body 27 by a plurality of bolts, and a front end portion of the flat plate member 29 disposed on the rear side of the arm main body 27 is fixed to an upper surface of the rear end portion 27b of the arm main body 27 by a plurality of bolts. The rear end surface of the plate member 29 disposed on the front side of the arm main body 27 is in contact with the front end surface of the central portion 27c, and the front end surface of the plate member 29 disposed on the rear side of the arm main body 27 is in contact with the rear end surface of the central portion 27 c.

The front end surface of the plate member 29 disposed on the front side of the arm main body 27 is disposed at substantially the same position as the front end surface of the plate member 28 in the front-rear direction, and the rear end surface of the plate member 29 disposed on the rear side of the arm main body 27 is disposed at substantially the same position as the rear end surface of the plate member 28 in the front-rear direction. The width of the plate member 29 in the left-right direction is equal to the width of the arm body 27 in the left-right direction, and both end surfaces of the plate member 29 in the left-right direction are in contact with the inner side surfaces of the plate member 28 in the left-right direction. The plate member 29 is also fixed to the plate member 28 by a plurality of bolts. The upper surface of the flat plate member 29 is disposed on the same plane as the upper surface of the central portion 27c, and the height of the upper surface of each of the left and right ends of the flat plate member 29 is slightly higher than the height of the upper surface of the portion of the flat plate member 29 other than the left and right ends (see fig. 7).

The flat plate member 32 is formed in a rectangular flat plate shape elongated in the front-rear direction. The thickness direction of the flat plate member 32 coincides with the left-right direction. The plate members 32 are disposed on both sides of the arm main body 27 in the front-rear direction and at the center of the arm 9 in the left-right direction. One end surface in the front-rear direction of the plate member 32 contacts the front-rear side surface of the arm main body 27. The other end surface in the front-rear direction of the flat plate member 32 is arranged at the same position in the front-rear direction as the end surface in the front-rear direction of the flat plate member 28.

The lower end surface of the plate member 32 is disposed at the same position as the lower end surface of the plate member 28 in the vertical direction. The upper end surface of the plate member 32 is in contact with the lower surface of the plate member 29. The plate member 32 is fixed to the plate member 29 by a plurality of bolts. A quadrangular prism-shaped fixing member is fixed to one end portion of the plate member 32 in the front-rear direction by a plurality of bolts, and the fixing member is fixed to the front-rear side surfaces of the arm main body 27 by a plurality of bolts. That is, the plate member 32 is also fixed to the arm main body 27 via the fixing member.

The flat plate member 30 is formed in a rectangular flat plate shape having a longitudinal direction in the left-right direction. The thickness direction of the plate member 30 coincides with the front-rear direction. The plate members 30 are disposed on both sides of the arm main body 27 in the front-rear direction, and on both sides of the plate member 32 in the left-right direction. The plurality of flat plate members 30 are arranged at a constant interval in the front-rear direction. In the present embodiment, the two flat plate members 30 are disposed at a fixed interval in the front-rear direction on both sides in the front-rear direction of the arm main body 27 and on both sides in the left-right direction of the flat plate member 32.

The lower end surface of the plate member 30 is disposed at the same position as the lower end surface of the plate member 28 in the vertical direction. The upper end surface of the plate member 32 is in contact with the lower surface of the plate member 29. The plate member 30 is fixed to the plate member 29 by a plurality of bolts. Both end surfaces of the flat member 30 in the left-right direction are in contact with the

flat members

28, 32, and the flat member 30 is further fixed to the

flat members

28, 32 by a plurality of bolts.

The flat plate member 34 is formed in a rectangular flat plate shape elongated in the front-rear direction. The thickness direction of the plate member 34 coincides with the vertical direction. The flat plate members 34 are disposed on both sides of the two flat plate members 28 in the left-right direction. The length of the plate member 34 in the front-rear direction is substantially equal to the length of the plate member 28 in the front-rear direction. The front end surface of the plate member 34 is disposed at substantially the same position as the front end surface of the plate member 28 in the front-rear direction, and the rear end surface of the plate member 34 is disposed at substantially the same position as the rear end surface of the plate member 28 in the front-rear direction. The inner end surface of the flat plate member 34 in the left-right direction is arranged at the same position as the inner side surface of the flat plate member 28 in the left-right direction. The lower surface of the plate member 34 is in contact with the upper end surface of the plate member 28. The plate member 34 is fixed to the plate member 28 by a plurality of bolts.

The flat plate member 36 is formed in a rectangular flat plate shape elongated in the front-rear direction. The thickness direction of the flat plate member 36 coincides with the left-right direction. The flat plate members 36 are disposed on both sides of the two flat plate members 28 in the left-right direction. The plate member 36 constitutes a lateral surface of the arm 9 in the right-left direction. The length of the plate member 36 in the front-rear direction is equal to the length of the plate member 34 in the front-rear direction. The front end surface of the plate member 36 is arranged at the same position as the front end surface of the plate member 34 in the front-rear direction, and the rear end surface of the plate member 36 is arranged at the same position as the rear end surface of the plate member 34 in the front-rear direction.

The lower end surface of the plate member 36 is disposed at the same position as the lower end surface of the plate member 28 in the vertical direction, and the upper end surface of the plate member 36 is disposed at the same position as the upper end surface of the plate member 28 in the vertical direction. The outer side surface of the flat plate member 36 in the left-right direction is arranged at the same position as the outer end surface of the flat plate member 34 in the left-right direction. The upper end surface of the plate member 36 is in contact with the lower surface of the plate member 34. The plate member 36 is fixed to the plate member 34 by a plurality of bolts.

The flat plate member 35 is formed in a rectangular flat plate shape whose vertical direction is the longitudinal direction. The thickness direction of the flat plate member 35 coincides with the front-rear direction. The plate members 35 are disposed on both sides of the two plate members 28 in the left-right direction. The plurality of flat plate members 35 are arranged at a constant interval in the front-rear direction. In the present embodiment, ten flat plate members 35 are disposed on both sides of the two flat plate members 28 in the left-right direction at a constant interval in the front-rear direction.

The lower end surface of the plate member 35 is disposed at the same position as the lower end surface of the plate member 28 in the vertical direction. The upper end surface of the flat plate member 35 is in contact with the lower surface of the flat plate member 34. The plate member 35 is fixed to the plate member 34 by a plurality of bolts. Both end surfaces of the plate member 35 in the left-right direction are in contact with the

plate members

28, 36, and the plate member 35 is also fixed to the

plate members

28, 36 by a plurality of bolts.

The flat plate member 31 is formed in a substantially rectangular flat plate shape having a longitudinal direction in the left-right direction. The flat plate member 31 is formed in a concave shape in which the center in the left-right direction is depressed toward the lower side. The thickness direction of the flat plate member 31 coincides with the front-rear direction. The plate members 31 are disposed on both sides of the arm main body 27 in the front-rear direction. The plate member 31 constitutes the front-rear direction side surface of the arm 9. The outer shape of the flat plate member 31 corresponds to the contour formed by the

flat plate members

28, 29, 34, and 36 (see fig. 7 a).

The lower end surface of the plate member 31 is disposed at the same position as the lower end surface of the plate member 28 in the vertical direction. The front-rear inner side surface of the plate member 31 is in contact with the front-rear outer side surfaces of the

plate members

28, 32. The upper end face of the plate member 31 is in contact with the lower faces of the

plate members

29, 34. The outer side surface in the left-right direction of the plate member 31 is in contact with the inner side surface in the left-right direction of the plate member 36. The plate member 31 is fixed to the

plate members

28, 29, 32, 34, 36 by a plurality of bolts.

The flat plate member 33 is formed in a rectangular flat plate shape whose longitudinal direction is the left-right direction. The thickness direction of the flat plate member 33 coincides with the vertical direction. The lower surface of the plate member 33 is disposed above the lower end surface of the plate member 28. The plate member 33 is fixed to the

plate members

28, 31, and 32 at the rear end portion of the arm 9 by a plurality of bolts.

As described above, the upper end surface of the plate member 28 is disposed above the upper surface of the arm main body 27. The upper end surface of the plate member 36 is disposed at the same position as the upper end surface of the plate member 28 in the vertical direction. Therefore, in the present embodiment, as shown in fig. 7, the height of the inner portions in the left-right direction of the two flat plate members 28 of the arm 9 is lower than the height of the outer portions in the left-right direction of the two flat plate members 28 of the arm 9.

The flat plate member 28 of the present embodiment is a first flat plate member. The plate members 29 to 32 of the present embodiment are second plate members disposed on both sides of the arm main body 27 in the front-rear direction. In the present embodiment, the plate member 29 is a third plate member that is fixed to the plate member 28 and is disposed in the thickness direction in the vertical direction, the

plate members

30 and 31 are fourth plate members that are fixed to the plate member 28 and are disposed in the thickness direction in the front-rear direction, and the plate member 32 is a fifth plate member that is fixed to the plate members 29 to 31 and is disposed in the thickness direction in the left-right direction.

In the present embodiment, the plate members 34 are sixth plate members that are disposed on both sides in the left-right direction of the two plate members 28 and are disposed with the vertical direction as the thickness direction, and are fixed to the plate members 28, the plate members 35 are seventh plate members that are disposed on both sides in the left-right direction of the two plate members 28 and are disposed with the front-rear direction as the thickness direction, and are fixed to the plate members 28, and the plate members 36 are eighth plate members that are disposed on both sides in the left-right direction of the two plate members 28 and are disposed with the left-right direction as the thickness direction, and are fixed to the

plate members

34, 35.

(hand and hand support Member Structure)

The hand 5 includes a plurality of forks 40 on which the workpiece 2 is loaded, and a hand base 41 to which base ends of the plurality of forks 40 are fixed. The hand 6 includes a plurality of forks 40 on which the workpieces 2 are loaded and a hand base 42 to which base ends of the plurality of forks 40 are fixed, as in the hand 5. The hands 5 and 6 of the present embodiment include four forks 40.

The fork 40 is formed in a linear shape elongated in the front-rear direction. The rear end of the fork 40 is fixed to the hand bases 41, 42. The hand base portion 41 constitutes a rear end portion of the hand 5, and the hand base portion 42 constitutes a rear end portion of the hand 6.

The hand base portions 41 and 42 are formed in a substantially rectangular flat plate shape elongated in the left-right direction. The length (length in the left-right direction) of the hand base portion 41 is shorter than the length (length in the left-right direction) of the hand base portion 42. The hand 5 and the hand 6 are arranged to overlap each other in the vertical direction when viewed from the front-rear direction. In the present embodiment, the hand 6 is disposed on the upper side and the hand 5 is disposed on the lower side when viewed from the front-rear direction. The width of the hands 5, 6 in the left-right direction is wider than the width of the arm 9 in the left-right direction. As shown in fig. 3, the hand 5 and the hand 6 are arranged such that the center of the hand 5 and the center of the hand 6 coincide with each other in the left-right direction when viewed from the front-rear direction. Further, the hands 5 and 6 are disposed so that the centers of the hands 5 and 6 and the center of the arm 9 coincide with each other in the left-right direction when viewed from the front-rear direction.

Even when the hands 5 and 6 move to the rearmost side with respect to the arm 9, the tip (front end) of the fork 40 is disposed at a position forward of the main body 10 (see fig. 1). That is, even when the hand support members 7 and 8 move to the rearmost side with respect to the arm 9, the front ends of the hands 5 and 6 are disposed at the front side of the main body 10. Therefore, the front ends of the hands 5, 6 are separated from the main body 10 as the hand support members 7, 8 move to the front side with respect to the arm 9.

The hand support member 7 is composed of two slide members 43 disposed below the hand base portion 41 (see fig. 13). The two slide members 43 are disposed with a gap therebetween in the left-right direction. The two slide members 43 are disposed between the two plate members 28 in the left-right direction. The shape of the slide member 43 when viewed from the front-rear direction is substantially L-shaped. The hand base 41 is fixed to an upper end surface of the slide member 43.

The hand support member 8 is composed of two slide members 44 disposed below the hand base 42. The two slide members 44 are arranged with a space therebetween in the left-right direction. The two slide members 44 are disposed outside the arm 9 in the lateral direction. The sliding member 44 has a substantially L-shape when viewed from the front-rear direction. The hand base 42 is fixed to an upper end surface of the slide member 44.

(Structure of drive mechanism and guide mechanism)

Fig. 10 is an enlarged view of a portion G of fig. 4. Fig. 11 is a side view for explaining the structures of the driving mechanism 17 and the guide mechanism 19 shown in fig. 10. Fig. 12 is a side view for explaining the structures of the driving mechanism 18 and the guide mechanism 20 shown in fig. 10. Fig. 13 is a rear view for explaining the structure of the

guide mechanisms

19 and 20 shown in fig. 10. Fig. 14 is a rear view for explaining the structures of the driving

mechanisms

17 and 18 and the

guide mechanisms

19 and 20 shown in fig. 10.

The drive mechanism 17 includes a motor 46, and pulleys 47 to 52 and belts 53 to 55 for transmitting power of the motor 46 to the hand support member 7. The motor 46 is housed in a motor housing part 56 fixed to the rear surface of the arm 9. A pulley 47 is fixed to an output shaft of the motor 46. As shown in fig. 11, the pulley 48 is fixed to an upper end portion of the rotating shaft 57, and the pulley 49 is fixed to a lower end portion of the rotating shaft 57. The rotary shaft 57 is rotatably held by the motor housing member 56 so as to be rotatable in the axial direction in which the vertical direction is rotational. The belt 53 is hung on the

pulleys

47 and 48.

As shown in fig. 11, the pulley 50 is fixed to a lower end portion of the rotating shaft 58, and the pulley 51 is fixed to an upper end portion of the rotating shaft 58. The rotary shaft 58 is rotatably held by the rear end portion of the plate member 29 and the plate member 33 disposed on the rear side so as to be rotatable in the axial direction in which the vertical direction is rotatable. The pulley 52 is fixed to the upper end of the rotating shaft. The rotation shaft is rotatably held at the distal end portion of the plate member 29 disposed on the front side so as to be rotatable in the axial direction in which the rotation shaft rotates in the vertical direction. The

pulleys

50 and 51 are disposed at the rear end of the arm 9, and the pulley 52 is disposed at the front end of the arm 9.

The pulley 50 is disposed inside the arm 9. The

pulleys

51, 52 are disposed above the plate member 29. The belt 54 is hung on the pulley 49 and the pulley 50. The belt 55 is hung on the

pulleys

51 and 52. The hand support member 7 is fixed to the belt 55. Specifically, the slide member 43 disposed on the left side is fixed to the belt 55. The belt 55 is disposed above the arm main body 27 and the plate member 29. The

pulleys

51 and 52 and the belt 55 are disposed inside the upper end portions of the two flat plate members 28 in the lateral direction. That is, a part of the drive mechanism 17 is disposed inside the upper end portions of the two plate members 28 in the left-right direction.

The drive mechanism 18 includes a motor 61, pulleys 62 to 67 for transmitting power of the motor 61 to the hand support member 8, and belts 68 to 70. The motor 61 is housed in a motor housing member 71 fixed to the right end portion of the rear surface of the arm 9. The pulley 62 is fixed to an output shaft of the motor 61. As shown in fig. 10, the pulley 63 is fixed to the right end portion of the rotary shaft 72, and the pulley 64 is fixed to the left end portion of the rotary shaft 72. The rotary shaft 72 is rotatably held by the motor housing member 71 so as to be rotatable in an axial direction in which the shaft rotates in the left-right direction. The belt 68 is hung on the

pulleys

62 and 63.

As shown in fig. 14, the pulley 65 is fixed to the rotating shaft 73. The pulley 66 is fixed to each of both ends of the rotating shaft 73 in the left-right direction. The rotary shaft 73 is rotatably held at the rear end portions of the two plate members 36 so as to be rotatable in the axial direction about the left-right direction. A pulley 67 is fixed to each of both ends of the rotating shaft in the left-right direction. The rotation shaft is rotatably held at the distal end portions of the two plate members 36 so as to be rotatable in the axial direction about the left-right direction. The

pulleys

65 and 66 are disposed at the rear end of the arm 9, and the pulley 67 is disposed at the front end of the arm 9.

The pulley 65 is disposed inside the arm 9. The

pulleys

66 and 67 are disposed on the outer side of the arm 9 in the left-right direction. A belt 69 (see fig. 10) is looped over the pulley 64 and the pulley 65. The belt 70 is suspended from the

pulleys

66 and 67. The hand support member 8 is fixed to the belt 70. Specifically, each of the two sliding members 44 is fixed to each of the two belts 70. The belt 70 is disposed on the outer side of the arm 9 in the left-right direction.

The guide mechanism 19 is disposed on the upper surface side of the arm 9. The guide mechanism 19 is disposed inside the upper end portions of the two plate members 28 in the lateral direction. The guide mechanism 19 includes four guide rails 76 whose longitudinal directions are the front-rear direction, and a guide block 77 that engages with the guide rails 76 from above. In the present embodiment, four guide blocks 77 are engaged with one guide rail 76. The guide rail 76 of the present embodiment is a first guide rail, and the guide block 77 is a first guide block.

Four guide rails 76 are fixed to the upper surfaces of the arm main body 27 and the plate member 29. Two of the four guide rails 76 are fixed to the right end side of the upper surfaces of the arm main body 27 and the plate member 29, and the remaining two guide rails 76 are fixed to the left end side of the upper surfaces of the arm main body 27 and the plate member 29. The guide block 77 is fixed to the lower end surface of the slide member 43. In the present embodiment, eight guide blocks 77 are fixed to one slide member 43. A cover 78 that covers the

pulleys

51 and 52, the belt 55, and the guide mechanism 19 from above is fixed to the arm 9. The cover 78 is disposed below the hand base 41.

The guide mechanisms 20 are disposed on both sides of the arm 9 in the left-right direction. The guide mechanism 20 includes four guide rails 80 whose longitudinal direction is the front-rear direction, and a guide block 81 that engages with the guide rails 80 from the outside in the left-right direction. In the present embodiment, four guide blocks 81 are engaged with one guide rail 80. The guide rail 80 of the present embodiment is a second guide rail, and the guide block 81 is a second guide block.

Two of the four guide rails 80 are fixed to the right surface of the panel member 36 disposed on the right side, and the remaining two guide rails 80 are fixed to the left surface of the panel member 36 disposed on the left side. That is, two of the four guide rails 80 are disposed on the right side of the arm 9, and the remaining two guide rails 80 are disposed on the left side of the arm 9. Further, two guide rails 80 disposed on each of the left and right sides of the arm 9 are disposed at an interval in the vertical direction, and the belt 70 is disposed between the two guide rails 80. The guide block 81 is fixed to the inner side surface of the slide member 44 in the left-right direction. In the present embodiment, eight guide blocks 81 are fixed to one slide member 44. A cover 82 that covers the

pulleys

66 and 67, the belt 70, and the guide mechanism 20 from the left and right outer sides and from the top and bottom sides is fixed to the arm 9.

(Structure of Link supporting Member and Link mechanism, and Wiring threading and winding)

The link support member 21 is fixed to the rear surface of the arm 9. The link support member 21 is composed of a first support portion 21a extending from the rear surface of the arm 9 toward the rear side, a second support portion 21b extending from the rear end of the first support portion 21a toward the right side, and a third support portion 21c extending from the right end of the second support portion 21b toward the upper side. The link mechanism 22 is disposed below the link mechanism 23 when viewed from the front-rear direction. The link mechanisms 22 and 23 include: a link member 85 having a base end portion rotatably connected to the link support member 21; and a link member 86 having a front end portion rotatably connected to a rear end portion of the hands 5, 6.

The base end of the link member 85 is connected to the link support member 21 so that the link member 85 can rotate in the axial direction in which the link member rotates in the vertical direction with respect to the link support member 21. Further, the base end portion of the link member 85 is rotatably connected to the rear surface side of the third support portion 21 c. The front end of the link member 86 is connected to the rear surface side of the hand base portions 41 and 42 so that the link member 86 can rotate in the axial direction in which the vertical direction is the rotation relative to the hands 5 and 6. The front end of the link member 86 is rotatably connected to the right end of the hand base portions 41 and 42.

The base end portion of the link member 86 is connected to the tip end portion of the link member 85 so that the link member 86 can rotate relative to the link member 85 in the axial direction in which the vertical direction is rotational. The connecting portion between the link member 85 and the link member 86 is disposed on the left side of the connecting portion between the link member 85 and the link support member 21 and the connecting portion between the link member 86 and the hand base portions 41 and 42. As shown by the two-dot chain lines in fig. 1, when the hands 5, 6 move forward relative to the main body portion 10, the link mechanisms 22, 23 extend, and as shown by the solid lines in fig. 1, when the hands 5, 6 move backward relative to the main body portion 10, the link mechanisms 22, 23 flex and contract. The

link members

85, 86 are formed in an elongated square groove shape.

In the present embodiment, the turning shaft 11 is turned in a state where the hands 5 and 6 are moved to the rearmost side with respect to the main body 10 (a state shown by a solid line in fig. 1), and the hands 5 and 6 and the arm 9 are turned. That is, the hands 5, 6 and the arm 9 are rotated in a state where the link mechanisms 22, 23 are bent. The maximum turning radius R1 (see fig. 1) at this time is substantially equal to the maximum turning radius when the robot 1 does not include the link mechanisms 22 and 23.

The wiring 24 is routed from the inside of the main body 10 to the hands 5 and 6. One end of the wire 24 is connected to a sensor provided on the hands 5 and 6. A part of the wiring 24 is disposed on the inner peripheral side of the rotating shaft 11 and in the through hole 27a of the arm main body 27. The wire 24 is routed from the through hole 27a toward the rear side along the upper surfaces of the arm main body 27 and the plate member 29, and then routed along the upper surface of the first support portion 21a, the front surface of the second support portion 21b, and the front surface of the third support portion 21 c. The wire harness 24 is routed to the hand base portions 41 and 42 along the link mechanisms 22 and 23. A part of the wiring 24 is housed inside the

link members

85, 86 formed in an elongated rectangular groove shape.

(main effect of the present embodiment)

As described above, in the present embodiment, the center portion of the arm 9 is constituted by the block-shaped arm main body 27, and the portions of the arm 9 other than the center portion are constituted by the flat plate members 28 to 36. Therefore, in the present embodiment, even if the moving distance of the hands 5 and 6 and the hand support members 7 and 8 with respect to the arm 9 becomes long and the arm 9 becomes large in the front-rear direction, the weight of the arm 9 can be reduced as compared with the case where the entire arm 9 is constituted by the block-shaped arm main body 27.

In the present embodiment, the arm main body 27, which is formed in a block shape and has high strength and rigidity, constitutes the center portion of the arm 9 and is fixed to the pivot shaft 11. In the present embodiment, the plate member 28 having a length in the front-rear direction longer than that of the arm main body 27 is fixed to each of the lateral sides of the arm main body 27 in the left-right direction, and the plate member 29 fixed to the plate member 28 and arranged with the vertical direction as the thickness direction, the

plate members

30 and 31 arranged with the front-rear direction as the thickness direction and fixed to the plate member 28, and the plate members 32 fixed to the plate members 29 to 31 and arranged with the left-right direction as the thickness direction are arranged on both sides of the arm main body 27 in the front-rear direction.

Therefore, in the present embodiment, even if the arm 9 is increased in size in the front-rear direction and the weight of the workpiece 2 mounted on the hands 5 and 6 is increased, the rigidity and strength of the arm 9 can be ensured. That is, in the present embodiment, even if the arm 9 is large in size and the weight of the workpiece 2 mounted on the hands 5 and 6 is heavy, the arm 9 can be reduced in weight and the rigidity and strength of the arm 9 can be ensured. In the present embodiment, since the flat plate member 28 is disposed over the entire region of the arm 9 in the front-rear direction, the rigidity and strength of the arm 9 can be improved.

In the present embodiment, both sides of the two flat plate members 28 of the arm 9 in the left-right direction are composed of a flat plate member 34 that is fixed to the flat plate member 28 and is disposed with the vertical direction as the thickness direction, a flat plate member 35 that is fixed to the flat plate member 28 and is disposed with the front-rear direction as the thickness direction, and a flat plate member 36 that is fixed to the

flat plate members

34, 35 and is disposed with the horizontal direction as the thickness direction. Therefore, in the present embodiment, even if the width of the arm 9 in the left-right direction is increased (that is, even if the arm 9 is increased in size in the left-right direction), the arm 9 can be reduced in weight and the rigidity and strength of the arm 9 can be ensured.

In the present embodiment, the arm main body 27 is fixed to the pivot shaft 11 at a position rearward of the center of the arm main body 27 in the front-rear direction. Therefore, in the present embodiment, the rigidity of the front portion of the arm 9 with respect to the pivot shaft 11 can be improved. Therefore, in the present embodiment, when the hands 5 and 6 and the hand support members 7 and 8 move forward relative to the arm 9, the arm 9 can be prevented from flexing about the pivot shaft 11. In the present embodiment, the

heavy motors

46 and 61 are disposed on the rear side of the arm 9, but the arm main body 27 is fixed to the pivot shaft 11 at a position on the rear side of the center of the arm main body 27 in the front-rear direction, and the portion of the arm main body 27 disposed on the front side of the pivot shaft 11 is heavy, so that the weight balance of all the components mounted on the upper end of the pivot shaft 11 with respect to the pivot shaft 11 can be ensured.

In the present embodiment, the total area of the plurality of recesses 27e disposed on the front side of the center in the front-rear direction of the arm main body 27 is larger than the total area of the plurality of recesses 27e disposed on the rear side of the center in the front-rear direction of the arm main body 27 when viewed in the vertical direction. Therefore, in the present embodiment, the rigidity and strength of the portion on the rear side of the center in the front-rear direction of the arm main body 27 (i.e., the portion of the arm main body 27 to which the pivot shaft 11 is fixed) can be ensured, and the weight of the arm main body 27 can be effectively reduced.

In the present embodiment, the guide mechanism 19 is disposed on the upper surface side of the arm 9, and the guide mechanism 20 is disposed on both sides of the arm 9 in the left-right direction. Therefore, in the present embodiment, the

guide mechanisms

19 and 20 are easily provided. In addition, in the present embodiment, since the

guide mechanisms

19 and 20 include the four

guide rails

76 and 80, even if the weight of the workpiece 2 placed on the hands 5 and 6 is heavy, the guide rails 76 and 80 and the guide blocks 77 and 81 can be provided in a relatively small size. Therefore, in the present embodiment, the

guide mechanisms

19 and 20 are more easily provided.

In the present embodiment, although a part of the drive mechanism 17 (specifically, the

pulleys

51 and 52 and the belt 55) and the guide mechanism 19 are disposed inside the upper end portions of the two flat plate members 28 in the lateral direction, the height of the inside portions of the two flat plate members 28 in the lateral direction of the arm 9 is lower than the height of the outside portions of the two flat plate members 28 in the lateral direction of the arm 9. Therefore, in the present embodiment, even if a part of the drive mechanism 17 and the guide mechanism 19 are disposed on the upper surface side of the arm 9, the part of the drive mechanism 17 and the guide mechanism 19 can be prevented from protruding upward from the upper surface of the arm 9.

(other embodiments)

The above embodiment is an example of the best mode of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention.

In the above embodiment, the plate member 32 may not be fixed to the plate member 29 or the

plate members

30 and 31. In the above embodiment, the plate member 36 may not be fixed to the plate member 34 or the plate member 35. In the above embodiment, the height of the inner portions of the two flat plate members 28 of the arm 9 in the left-right direction and the height of the outer portions of the two flat plate members 28 of the arm 9 in the left-right direction may be the same. In the above embodiment, the plate member 28 may not be disposed over the entire region in the front-rear direction of the arm 9. In the above embodiment, the arm 9 may not include the plate members 34 to 36.

In the above embodiment, the center portion of the arm main body 27 in the front-rear direction may be fixed to the pivot shaft 11. In the above embodiment, the total area of the plurality of recesses 27e arranged on the front side of the center in the front-rear direction of the arm main body 27 may be equal to the total area of the plurality of recesses 27e arranged on the rear side of the center in the front-rear direction of the arm main body 27. In the above embodiment, the recess 27e may not be formed in the arm main body 27. In the above embodiment, the arm main body 27 may be cast.

In the above embodiment, the

pulleys

51 and 52, the belt 55, and the guide mechanism 19 may be disposed on both sides of the arm 9 in the left-right direction. In the above embodiment, the number of the guide rails 76 provided in the guide mechanism 19 may be two. Similarly, the number of the guide rails 80 provided in the guide mechanism 20 may be two. In the above embodiment, the number of hands included in the robot 1 may be one. In the above embodiment, the hand support members 7 and 8 may be moved in the front-rear direction by using a ball screw. The robot 1 may transport the workpiece 2 in the air.

Claims

1. An industrial robot, comprising:

a hand on which a conveyance object is loaded; a hand support member that fixes a base end portion of the hand; an arm that holds the hand support member such that the hand support member can linearly reciprocate in a horizontal direction; a body portion connecting the arms; and a drive mechanism that reciprocates the hand support member with respect to the arm,

the main body portion includes a pivot shaft for fixing the arm and a pivot mechanism for pivoting the pivot shaft,

when the reciprocating direction of the hand support member relative to the arm is defined as a front-rear direction and a direction orthogonal to the up-down direction and the front-rear direction is defined as a left-right direction,

the arm is provided with: a block-shaped arm main body which constitutes a center portion of the arm and is fixed to the rotation shaft; a first flat plate member fixed to each of left and right side surfaces of the arm main body; and a plurality of second flat plate members arranged on both sides of the arm main body in the front-rear direction,

the thickness direction of the first flat plate member is coincident with the left-right direction,

a length in the front-rear direction of the first plate member is longer than a length in the front-rear direction of the arm main body,

the front end of the first plate member is disposed at a position forward of the front end of the arm body,

the arm includes, as the plurality of second flat members: a plurality of third plate members which are arranged in a thickness direction from the top to the bottom and fixed to the first plate member; a plurality of fourth plate members arranged in a thickness direction of the plate members in the front-rear direction and fixed to the first plate member; and a plurality of fifth plate members that are arranged with the thickness direction in the lateral direction and are fixed to at least one of the third plate member and the fourth plate member.

2. The industrial robot of claim 1,

the first flat plate member is disposed in the entire region in the front-rear direction of the arm.

3. The industrial robot according to claim 1 or 2,

the front end of the hand separates from the main body portion as the hand support member moves forward relative to the arm,

the arm main body is fixed to the pivot shaft at a position rearward of a center of the arm main body in the front-rear direction.

4. The industrial robot according to claim 3,

the arm body is formed with a plurality of recesses recessed from a lower surface of the arm body toward an upper side,

the total area of the plurality of concave portions arranged on the front side of the center in the front-rear direction of the arm main body is larger than the total area of the plurality of concave portions arranged on the rear side of the center in the front-rear direction of the arm main body when viewed in the vertical direction.

5. Industrial robot according to claim 1 or 2,

the arm is provided with: a plurality of sixth plate members that are flat plate-shaped, are disposed on both sides in the left-right direction of the two first plate members, are disposed in the thickness direction in the up-down direction, and are fixed to the first plate members; a plurality of seventh plate members that are flat plate-shaped, that are disposed on both sides of the two first plate members in the left-right direction, that are disposed with the front-rear direction as the thickness direction, and that are fixed to the first plate members; and a plurality of eighth plate members that are flat plate-shaped, are disposed on both sides of the two first plate members in the left-right direction, are disposed with the left-right direction as the thickness direction, and are fixed to at least one of the sixth plate member and the seventh plate member.

6. The industrial robot according to claim 1 or 2, characterized by comprising:

first and second hands as the hands; a first hand support member as the hand support member for fixing the proximal end portion of the first hand; a second hand support member as the hand support member for fixing the proximal end portion of the second hand; a first driving mechanism as the driving mechanism for reciprocating the first hand support member with respect to the arm; a second driving mechanism as the driving mechanism for reciprocating the second hand support member with respect to the arm; a first guide mechanism for guiding the first hand support member in the front-rear direction; and a second guide mechanism for guiding the second hand support member in the front-rear direction,

the first guide mechanism is disposed on the upper surface side of the arm,

the second guide mechanism is disposed on both sides of the arm in the left-right direction.

7. The industrial robot of claim 6,

the first guide mechanism includes: four first guide rails with the front-back direction as the long side direction; and a first guide block engaged with the first guide rail from the upper side,

the second guide mechanism includes: four second guide rails with the front-back direction as the long side direction; and a second guide block engaged with the second guide rail from the outside in the left-right direction,

two of the four second guide rails are disposed on the right side of the arm, and the remaining two second guide rails are disposed on the left side of the arm.

8. The industrial robot of claim 6,

the arm is provided with: a plurality of sixth plate members that are flat plate-shaped, are disposed on both sides in the left-right direction of the two first plate members, are disposed in the thickness direction in the up-down direction, and are fixed to the first plate members; a plurality of seventh plate members that are flat plate-shaped, that are disposed on both sides of the two first plate members in the left-right direction, that are disposed with the front-rear direction as the thickness direction, and that are fixed to the first plate members; and a plurality of eighth plate members each having a flat plate shape, disposed on both sides of the two first plate members in the lateral direction, disposed with the lateral direction being the thickness direction, and fixed to at least one of the sixth plate member and the seventh plate member,

the height of the inside parts in the left-right direction of the two first flat plate parts of the arm is lower than the height of the outside parts in the left-right direction of the two first flat plate parts of the arm,

the first drive mechanism and the first guide mechanism are disposed on the inner side in the lateral direction of the upper end side portions of the two first plate members.

9. The industrial robot of claim 7,