JP2003089088A - Conveyance device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveyance device using a link mechanism and capable of letting an object to be conveyed advance substantially straight and conveying it at an offset position from a terminal of a first link. SOLUTION: This conveyance device 1 is attached to a wrist of an upper part arm 6 of a robot 3 and is composed of the first link 10, a second link 11, and a holding means 12. A length of the first link 10 differs from that of the second link 11. A terminal part of the first link 10 is attached to the wrist 7 of the robot 3 and is rotated and driven by a wrist shaft. A terminal part of the second link 11 is rotatably connected with a tip part of the first link 10. The holding means 12 is rotatably attached to a tip part of the second link 11. The second link 11 is rotated by a driven rotation means for link for transmitting the rotation of the first link 10 for the arm 6 of the robot, and the holding means 12 is rotated by a driven rotation means 15 for holding means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device using a link mechanism.

[0002]

2. Description of the Related Art FIG. 16 is a diagram showing a structure of a conventional conveying apparatus 100 using a link mechanism 103. Carrier 1
00 has a link mechanism 103 composed of a first link 101 and a second link 102, and expands and contracts in both directions by rotating the link. By reciprocating in this way, conveyance between two points is performed.

[0003]

In the carrying device 100,
The first link 101 and the second link 102 have the same length.
In this case, the work W held at the tip of the second link 102 goes straight along the line A on the base end of the first link 101. Therefore, for example, a motor installed at the base end of the first link 101 is on the line A, and the work W
When the workpiece W is conveyed on the line B offset from the line A, the first link 101 and the second link 101
If the links 102 have the same length, it cannot be realized.

In some cases, a transfer device using this link mechanism is attached to the end of the arm of a robot for use. In this case, when the work is transferred offset from the movement line of the end of the robot, This cannot be realized if the lengths of the first link 1 and the second link 2 are equal.

Further, in order to improve the rigidity of the link mechanism, the second link may be shorter than the first link.

An object of the present invention is to provide a carrier device using a link mechanism, which is capable of carrying an object to be conveyed in a straight line at a position offset from the base end of the first link while keeping the posture constant. It is to be.

[0007]

According to a first aspect of the present invention, there is provided a transporting device having a link mechanism capable of expanding and contracting, and a holding means provided at a tip end portion of the link mechanism for holding an object to be transported. The link mechanism is rotatably attached to a rotatable first link and a tip of the first link.
A second link having a length different from that of the link, and during transportation, by rotating the second link in synchronization with the rotation of the first link to expand and contract the link mechanism, the holding means is made substantially linear. It is a carrying device characterized by moving and carrying.

According to the present invention, since the lengths of the first link and the second link are different, the transported object held at the tip of the second link is offset from the base end of the first link, It can move almost straight.

According to a second aspect of the present invention, when the first link rotates, the second link has a driven follower rotating means for rotating the second link at a predetermined rotation ratio with respect to the rotation of the first link. It is characterized in that the rotation ratio of the link driven rotation means is set so that the path becomes substantially straight.

According to the present invention, since the link driven rotation means for driving the second link to rotate in response to the rotation of the first link is provided, it is not necessary to separately provide a drive source for driving the second link. By setting the rotation ratio of the second link with respect to the first link so that the movement path of the tip of the second link becomes substantially straight, it is possible to carry out straight conveyance.

According to a third aspect of the present invention, the rotation ratio of the link driven rotation means is set so that the first link and the second link have a relationship of 180 ° at the start point or the end point of the conveyance path. It is characterized by

According to the present invention, the first link and the second link are 180 ° at the start point or the end point of the conveyance. In other words, it is in a straight line. As a result, the transport distance can be increased.

According to the fourth aspect of the present invention, the moving path of the holding means is brought close to a straight line by stopping the first link and the second link at a predetermined angle from 180 ° at the start point or the end point of the transport path. The rotation ratio of the link driven rotation means is set so as to stop at the start point or the end point with the predetermined angle deviation.

When the lengths of the first link and the second link are different, if the first link and the second link are extended up to a straight line at the start point or the end point of the transport path, the end of the transport path is likely to deviate from the straight transport path. Become. According to the present invention, the transport path can be brought closer to a straight line by stopping the first link and the second link at an angle deviated from 180 ° at the transport start point or the transport end point.

According to a fifth aspect of the present invention, the rotation ratio of the driven follower rotating means is set so that the first link is parallel to the transport path at the start point or the end point of the transport path. To do.

The present invention as set forth in claim 6 is characterized in that the rotation ratio of the driven follower rotating means is set such that the second link is parallel to the transport path at the start point or the end point of the transport path. To do.

According to the invention, at the end of the transport path, the first
By controlling the link or the second link to be parallel to the transport path, it is possible to easily determine the rotation ratio of the link driven rotation means so that the transport path approaches the straight line.

According to a seventh aspect of the present invention, when the second link rotates, the holding means has a driven rotating means for rotating the holding means at a predetermined rotation ratio with respect to the rotation of the second link. It is characterized in that the rotation ratio of the driven rotation means for holding means is set so that the posture of the transported object is kept constant.

According to the present invention, by using the driven rotating means for the holding means, it is possible to make the posture of the conveyed object constant and convey the conveyed object in a non-inverted manner.

The present invention according to claim 8 is characterized in that a base end portion of the first link is attached to a wrist at a tip end of an arm of a robot.

According to the present invention, it is possible to extend the transfer distance by attaching the transfer device to the tip of the arm of the robot and rotating the link bidirectionally in synchronization with the swing of the arm.

[0022]

1 is a side view showing a robot system 2 provided with a carrying device 1 according to an embodiment of the present invention, and FIG. 2 is a plan view thereof. The carrier device 1 is attached to the wrist 7 of the robot 3 and is provided with a pair of press machines 20, 2
It is used to convey the work W between the ones.

The robot 3 is a 6-axis vertical articulated robot and has a base 4, a lower arm 5, an upper arm 6 and a wrist 7 fixed to the floor. The lower arm 5 is attached to the base 4 such that the lower end thereof is rotatable about a vertical first axis J1 and is provided on the base 4 so as to be rotatable back and forth about a horizontal second axis J2. A base end portion of the upper arm 6 is attached to an upper end portion of the lower arm 5 so as to be vertically rotatable about a horizontal third axis J3. The wrist 7 attached to the tip of the upper arm 6 is rotatably attached around a fourth axis J4 parallel to the axis of the upper arm 6 and rotatable around a fifth axis J5 perpendicular to the axis of the upper arm 6. Mounted on. Then, the carrier device 1 is attached to the wrist 7. The wrist axis of the wrist 7 is the sixth axis J which is perpendicular to the fifth axis J5.
Rotate around 6.

The joint axes J1 to J6 of the robot 3 are individually driven to rotate by servomotors, and the wrist axis is connected to the first link 10 and the sixth axis J to the upper arm 6.
Rotate around 6.

The carrier device 1 includes a first link 10 and a second link 10.
The link mechanism 9 includes a link 11 and a holding means 12 provided at the tip of the second link 11. The base end portion 11a of the second link 11 is rotatably attached to the tip end portion 10b of the first link 10 about a rotation axis A1 parallel to the sixth axis J6.
The holding means 12 is attached to 1b. The holding means 12 is
It is provided rotatably around a rotation axis A2 parallel to the sixth axis J6 and the rotation axis A1, and has a plurality of suction cups 13, and these suction cups 13 hold the work W detachably. Second
The length L2 of the link 11 is half the length L1 of the first link 10. That is, the length L2 between A1 and A2 is J6.
It is 1/2 of the length L1 between −A1.

The robot 3 of the robot system 2 is installed in the center of the two press machines 20 and 21, and the one press machine 20 in the first position on the left side of FIG. 2 to the second press machine on the right side of FIG.
The work W is conveyed to the other press 21 in the position.
The robot 3 holds the carrier device 1 substantially horizontally so that the sixth axis J6 is vertical, swings the upper arm 6 about the first axis J1, and synchronizes with the swing of the upper arm 6. The reciprocating motion of the link mechanism 9 of the carrier device 1 is performed. At this time, the movement path of the holding means 12 provided at the tip of the second link 11 becomes the conveyance path L. As described above, since the length L1 of the first link 10 and the length L2 of the second link 11 are different, the transport route L is the first link 10
Is located at a position offset from the line C, which is the movement path of the base end portion 10a.

Next, the transfer operation of the robot system 2 will be described in more detail with reference to FIG.

As shown in FIG. 3 (1), the transfer device 1 is extended to one press 20 side together with the upper arm 6 and the work W is held by the holding means 12 and then the first link 10 is held.
Rotates in the first rotation direction (clockwise in FIG. 3),
While the second link 11 rotates in the second rotation direction (counterclockwise in FIG. 3), the holding means 12 rotates in the first rotation direction (clockwise in FIG. 3). By rotating in this way, the work W starts moving while maintaining the same direction as the held state.

When the first link 10 is further rotated in the first rotation direction, the state shown in FIG.
As shown in (3), the carrier device 1 is folded at the central portion between the press machines 20 and 21. At this time, the upper arm 6 of the robot 3 is arranged vertically to the transport path L, and the first link 10 and the second link 11 are folded and arranged vertically to the transport path L.

Further, while the upper arm 6 is swung to the other side and the first link 10 is rotated in the first rotation direction, the carrier W is kept in the same direction while keeping the workpiece W in the same direction. Extend to the side. In this way, through the state of FIG. 3 (4), the first link 10 and the second link 11 are extended to a straight line, and the work W is conveyed to the pressing machine 21 on the other side. As shown in FIG. 3 (5), the orientation of the work W after the completion of the transportation is the same as the orientation of the work W at the start of the transportation shown in (1).

Next, the link mechanism 9 will be described. The link mechanism 9 includes a first link 10, a second link 11, and
Linked rotation means 8 for transmitting the rotation of the first link 10 with respect to the upper arm 6 of the robot to the second link 11 and rotating the second link 11 with respect to the first link 10,
And a driven rotation means 15 for holding means for transmitting the rotation of the second link 11 with respect to the first link 10 to the holding means 12 and rotating the holding means 12. FIG. 4 is a plan view showing the internal structure of the carrier device 1, and FIG. 5 is a side view thereof.

The first link 10 is a hollow first link body 2
2 has a base end 10a fixed to the wrist 7,
The link body 22 is rotationally driven by a servo motor M6 that drives the wrist shaft of the robot. Inside the first link body 22, the first sun gear 25 is provided on the base end 10a side.
Is provided. This first sun gear 25 is fixedly connected to the upper arm 6 of the robot, and when the first link 10 is rotated by the wrist axis, the first sun gear 25
Will rotate relative to the first link 10. A first planetary gear 26, which is rotatably supported around a rotation axis A1 parallel to the axis J6 of the sixth shaft, is provided at the tip portion 10b of the first link body 22.
From the first planetary gear 26 to the timing belt 2
7 is wound. The first sun gear 25, the first planetary gear 26, and the timing belt 27 constitute the link driven rotation means 8. The first planetary gear 26 is rotatably supported by the first link body 22 by a bearing 28, and the base end portion 11a of the second link 11 is fixed, so that the first planetary gear 26 is integrated with the first planetary gear 26 to form the second planetary gear 26. Link 11
Rotates.

A second sun gear 36 is provided at the proximal end of the hollow second link body 39, and a second planetary gear 37 is provided at the distal end.
The holding means 12 is connected to the second planetary gear 37, and the holding means 12 rotates together with the second planetary gear 37. A timing belt 38 is wound around the second sun gear 36 and the second planetary gear 37. The second sun gear 36, the second planetary gear 37, and the timing belt 38 constitute the holding means driven rotation means 15.

As shown in FIG. 6, the second sun gear 36 is
The first link 1 is fixedly connected to the first link body 22.
It rotates together with 0. Although the first planetary gear 26 and the second sun gear 36 have a common axis of rotation A1, the first planetary gear 26 is fixedly connected to the second link body 39 via the shaft 34, as shown in FIG. And is rotated around the rotation axis A1 integrally with the second link 11, and the second sun gear 36 is
It is fixedly connected to the link body 22 and integrated with the first link 10. The second planetary gear 37 is the tip end portion 11a of the second link 11 main body and has a rotation axis A2 parallel to the rotation axis A1.
The second link body 39 is rotatably supported around the second link body 39.

Since the timing belt 27 is wound around the first sun gear 25 and the first planetary gear 26, as shown in FIG. 4, the first link 10 is rotated by the first rotation while the gear 25 is fixed. When rotated in the direction (clockwise in the plane of FIG. 4), the timing belt 26 rotates as indicated by the arrow in FIG. 4, which causes the first planetary gear 26 to rotate.
Rotates in the second rotation direction (counterclockwise). As described above, the first planetary gear 26 and the second link 11 are fixed and rotate integrally, so that the first link 1
By rotating 0 in the first rotation direction, it is possible to rotate the second link 11 together with the first planetary gear 26 in the second rotation direction.

The driven follower rotating means 8 for the link is the first link 1
When 0 rotates, the second link 11 is rotated at a predetermined rotation ratio.

Next, the rotation ratio of the link driven rotation means 8 will be described with reference to FIG. In FIG. 7, the robot arm 6 does not swing, and the first link 10
Shall swing about the sixth axis J6 at the base end.
In addition, the x-axis and the y-axis are set around the sixth axis, and the first
A state in which the link 10 and the second link 11 overlap with the y-axis at the center is referred to as a state I, a state in which the holding means 12 is at the end point of the conveyance path, and the first link 10 and the second link 11 are in a straight line is referred to as a state II. To do. In this way, the first link 10 and the second link
In the following, it is standard that the end point of the transport path is when the link 11 is aligned. The length of the first link is L1,
The length of the second link is L2. Here, it is assumed that L2 / L1 = M. In FIG. 7A, the case of 1 <M is shown.
(2) shows the case where M> 1. In the case of the transport device 1 described with reference to FIGS. 1 to 6, M = 1/2. Further, when the angle between the first link 10 and the y axis in the state II is α _L °, cos α _L = (1−M) / (1 + M). When M> 1, that is, in FIG. 7 (2), when the angle between the first link 10 and the y axis is α _L ′, And becomes the same as the case of M <1.

At the end of conveyance, the rotation ratio of the second link 11 to the rotation of the first link 10 is set so as to be in the state II. This is the standard rotation ratio.

The total rotation angle of the first link 10 is α _L °, the total rotation angle of the second link 11 is 180 °, the intermediate angle of the first link 10 is θ _L, and the intermediate angle of the second link 11 is If φ _L , then α _L : 180 = θ _L : φ _L, so φ _L = (180 / α _L ) · θ _L (1) Based on the relationship of the above equation (1), the link driven rotation means 8 is set to a rotation ratio of 180 / α _L. That is, the standard rotation ratio is 180 / α _L.

At this time, the holding means 12 provided at the tip end
The position of y in the y-axis direction is {cos θ _L −M cos (φ _L −θ _L )} · L1 = {cos θ _L −Mc
os the _{(180 · θ L / α L} ) -θ L} · L1. In FIG. 8, holding means 12 with M as a parameter
3 shows a graph of the position in the y-axis direction. As can be seen from this graph, even when the first link 10 and the second link 11 have different lengths, they move in a substantially straight line.

During transportation, the driven rotating means 15 for holding means
Then, the rotation of the second link 11 is transmitted to the holding means 12,
By rotating the holding means 12, the posture of the work is kept constant during conveyance. Next, the posture of the work during transportation will be described.

In order to maintain the posture of the work in the state I also in the state II, the driven rotating means 15 for the holding means.
Determine the rotation ratio of. That is, the first link 10 is 0 °
The rotation angle of the holding means 12 is 0 when rotating from α _L ° to
Rotate from ° to (180-α _L ) °. Therefore, the first
When the link is θ _L °, the holding means 12 rotates {(180−α _L ) / α _L } · θ _L (2). Second link 1 for rotation of first link 10
The rotation ratio of 1 is 180 / α _{L according to the} equation (1),
The rotation ratio of the holding means 12 with respect to the rotation of the link 10 is (180−α _L ) / α _{L according} to the equation (2).

Therefore, the rotation ratio of the holding means 12 with respect to the rotation of the second link 11 is {(180-α _L ) / α _L } / (180 / α _L ) = (18
It becomes 0-α _L ) / 180.

Thus, when the rotation ratio is determined, the posture angle of the holding means 12 as viewed from the absolute coordinate system is θ _L −φ _L + (180−α _L ) · θ _L / α _L = θ _L −180 · θ _L / α _L + (180−α _L ) · θ _L / α _L = 0, which is always a constant direction. The position of the holding means 12 in the x-axis direction is {sin θ _L + Msin (φ _L −θ _L )} · L1. This is shown in a graph in FIG.

Next, with reference to FIG. 10, a description will be given of a case where the rotation ratio of the link driven rotation means 8 is changed from the standard in order to improve the accuracy of straight-forward conveyance. In the case of FIG. 7, as a standard, the end point of the transport path is when the first link 10 and the second link 11 are aligned. In other words, at the end point, the first link 10 and the second link 11
The angle formed by and becomes 180 °. The angle formed by the first link 10 and the second link 11 at the end of the conveyance path is 180 · (1 + δ) with respect to the standard 180 °. cos α _L = (1−M) / (1 + M) α _L : 180 · (1 + δ) = θ _L : φ _L Therefore, φ _L = {180 · (1 + δ) / α _L } · θ _L. Based on this, the rotation ratio of the second link 11 to the first link 10 is set to {180 · (1 + δ)} / α _L (3). At this time, the position of the holding means 12 in the y-axis direction is [cos θ _L −Mcos {180 (1 + δ) · θ _L / α _L } −
θ _L ] · L1.

When M = 0.5, δ = −0.03, −
The position of the holding means 12 in the y-axis direction is calculated using 0.02, -0.01, 0, +0.01, +0.02 as parameters, and the result is shown in the graph of FIG.

In this case, when θ _L at −2% is 60 ° or less, the maximum value of the positional deviation is half or less as compared with the standard 0%.

In this case, when the first link rotation angle at the maximum extension position in the x-axis direction is 70 °, the rotation angle is 6 degrees.
The second link 1 with respect to the first link 10 is suppressed to 0 °
The rotation ratio of 1 is changed by -2%, that is, the rotation ratio of standard is 1.
80 / α _L = 2.552 to 2.552 × 98% = 2.
If the number is changed to 50096, the positional deviation can be reduced, and thus such a rotation ratio may be set.

When M = 2, δ = −0.01,
The position of the holding means 12 in the y-axis direction is calculated using 0, +0.01, +0.02, +0.03 as parameters, and the result is shown in the graph of FIG. In this case, θ _L at + 2% is 9
When the angle is 0 ° or less, the maximum value of the positional deviation is ¼ or less as compared with the standard 0%.

In this case, when the first link rotation angle at the maximum extension position in the x-axis direction is 110 °, the rotation angle is suppressed to 90 ° and the rotation ratio of the second link 11 to the first link 10 is +2. % Change, that is, the rotation ratio of the standard 180 / α _L '= 1.664 to 1.644 × 102%
If the value is changed to 1.67688, the positional deviation can be reduced, and thus such a rotation ratio may be set.

Regarding the posture, the work W in the state I
The rotation ratio of the driven rotation means 15 for the holding means is determined so that this posture is maintained at the end position.

Holding means 1 for rotation of the second link 11
If the rotation ratio of 2 is determined to be {180 (1 + δ) −α _L } / 180 (1 + δ), the rotation ratio of the second link 11 with respect to the rotation of the first link 10 is 180 (1 + δ) / α
_Since it is _L , the rotation ratio of the holding means 12 with respect to the rotation of the first link 10 is [{180 (1 + δ) −α _L } / {180 (1 + δ)}].
/ [180 (1 + δ) / α _L ] = {180 (1 + δ)-
α _L } / α _L.

When the rotation ratio of the driven rotating means 15 for the holding means is determined in this way, the angle of the holding means 12 when viewed from the absolute coordinate system is θ _L −φ _L + {180 (1 + δ) −α _L } .θ. _{L / α L = θ L -180} (1 + δ) · θ L / α L +180 (1 + δ) · θ L / α L -θ L = 0 becomes always constant direction.

Next, as another simple method for changing the rotation ratio from the standard, the rotation of the link driven rotation means 8 when the first link 10 and the second link 11 are not aligned at the end of the conveyance path. A method for determining the ratio will be described.

First, as shown in FIG. 13, when M <1, the rotation ratio is determined so that the first link 10 is at the M level and the second link 11 is parallel to the transport path L. First link 10 and second link 11 at the end of the transport route
When the angle of bets and beta _L, since it is _{β L = 90 + α L cosα} L = 1-M φ L / β L = θ L / α L, φ L = a _{(90 + α L) · θ} L / α L Become. The position of the holding means 12 in the y-axis direction is {cos θ _L −M cos (φ _L −θ _L )} · L1 = [cos θ _L −Mc
the _{os {(90 + α L)} · θ L / α L -θ L}] · L1.

When M = 0.5, the rotation ratio of the second link 11 to the first link 10 of the link driven rotation means 8 is (90 + α _L ) / α _L = 2.5, where M = 0.5. In the case of, the standard rotation ratio is 180
/ Α _L , which is 2.552. Therefore, in the case of this example, the change rate with respect to the standard rotation ratio is 2.5 / 2.552 = 0.9757≈0.98, which is almost equivalent to the case of −2% in the graph shown in FIG. According to this method, M = 0.
In the case of 5, the range of motion of the first link 10 is maximum 70
The holding means 12 in the x-axis direction may be set to 60 ° instead of 60 °.
Since the positions of are substantially the same, it is possible to easily determine the rotation ratio change rate with good straightness accuracy within the angle range.

Next, referring to FIG. 14, in the case of M> 1, in the case where the first link 10 and the second link 11 are not aligned with each other at the end point of the transport path L, the following driven rotating means 8 for link is used. A method of determining the rotation ratio will be described.

In this case, as shown in FIG. 14, when the first link 10 comes to a position parallel to the conveyance path L (rotation by 90 °), the tip of the second link 11 is positioned at the level of 1-M. Then, the rotation ratio of the driven rotation means 8 for link is determined.

Β _L = 90 + cos ^-1 {(M-1) / M} φ _L / β _L = θ _L / 90 Therefore, φ _L = [90 + cos ^-1 {(M-1) / M} · θ _L − θ _L ] ・
L1

When M = 2, the rotation ratio of the second link 11 with respect to the rotation of the first link 10 is [90 + cos ^-1 {(M-1) / M}] / 90 = 1.66.
6 By the way, the standard rotation ratio of the link driven rotation means 8 when M = 2 is 1.644 from the equation (1). Therefore, the change ratio to the standard rotation ratio in the case of this example is 1.666 / 1.644 = 1.014, which corresponds to the case of + 1.4% in the graph of FIG.

According to this method, M = in the graph of FIG.
In the case of No. 2, even if the movable range of the first link 10 is set to 90 ° instead of 110 °, the position of the holding means 12 in the x-axis direction is almost the same. Can be easily determined.

Next, various forms of the link mechanism of the carrying apparatus of the present invention will be described with reference to FIG. In the above-described embodiment, when the first link 10 rotates outside the robot arm 6 (upper side in FIG. 15), (1)
Although the M <1 type (FIG. 7 (1)) and (2) M> 1 type (FIG. 7 (2)) have been described, in addition to this, the first link 10 is located inside the robot arm 6 ( In some cases, the lower part of FIG. 15 may be rotated, and there are (3) M <1 type and (4) M> 1 type, respectively.

Further, the form of the link mechanism of the conveying apparatus of the present invention is not limited to the type composed of the first link and the second link as described above, and, for example, an N type in which a third link is added, and a fourth link It may be in the form of an additional W-shape.

Further, in each of the above-described embodiments, the carrying device is configured to reciprocate in both directions, but the present invention is not limited to this, and may be configured to reciprocate in only one direction. Also,
Instead of attaching the transfer device to the tip of the arm of the robot for use, the base mechanism of the first link 10 may be rotated by a motor to expand and contract the link mechanism. In this case as well, the transport path is at a position offset from the base end portion of the first link, so that it is possible to avoid the work from interfering with the motor that drives the transport device.

[0065]

As described above, according to the present invention, since the lengths of the first link and the second link are different, the transported object held at the tip of the second link is the base end of the first link. It is possible to move in a straight line at a position offset from. With this, even when the servo motor or the like for driving the carrying device is located at the base end portion of the first link, it is possible to carry it while avoiding this.

Further, according to the present invention, since the driven follower rotating means for the link for rotating the second link in response to the rotation of the first link is provided, it is not necessary to separately provide a drive source for driving the second link. . By setting the rotation ratio of the second link with respect to the first link so that the movement path of the tip of the second link becomes substantially straight, it is possible to carry out straight conveyance.

Further, according to the present invention, the first link and the second link are 180 ° at the start point or the end point of the transport path.
In other words, it is in a straight line. As a result, the transport distance can be increased.

Further, according to the present invention, the rotation ratio of the driven follower for link is changed so that the first link and the second link stop at an angle deviated from 180 ° at the start point or the end point of the conveyance. Therefore, it is possible to improve the straight traveling accuracy.

Further, according to the present invention, at the end point of the transport path,
By changing the rotation ratio of the driven follower for link so that the first link or the second link is parallel to the conveyance path, it is possible to easily determine the rotation ratio with good straight traveling accuracy.

Further, according to the present invention, by using the driven rotating means for the holding means, it is possible to make the posture of the conveyed object constant and convey it non-inverted.

Further, according to the present invention, the carrying distance can be extended by attaching the carrying device to the tip of the arm of the robot and rotating the link bidirectionally in synchronization with the swing of the arm.

[Brief description of drawings]

FIG. 1 is a side view showing a robot system 2 using a carrying device 1 according to an embodiment of the present invention.

FIG. 2 is a plan view of the robot system 2.

FIG. 3 is a diagram showing a carrying process by the carrying device 1.

FIG. 4 is a plan view showing an internal mechanism of the carrier device 1.

5 is a side view showing an internal mechanism of the transfer device 1. FIG.

6 is a cross-sectional view showing the vicinity of a first planetary gear 26 and a second sun gear 36 of the transfer device 35. FIG.

FIG. 7 is a diagram for explaining a rotation ratio of a link driven rotation means 8.

FIG. 8 is a graph showing the position of the holding means 12 in the y-axis direction with M as a parameter.

FIG. 9 is a graph showing the position of the holding means 12 in the x-axis direction with M as a parameter.

FIG. 10 is a diagram for explaining a change in the rotation ratio of the linked driven rotation means 8.

FIG. 11 is a graph showing the position of the holding means 12 in the y-axis direction when the rotation ratio of the link driven rotation means 8 is changed at M = 0.5.

FIG. 12 is a graph showing the position of the holding means 12 in the y-axis direction when the rotation ratio of the link driven rotation means 8 is changed when M = 2.

FIG. 13 is a diagram showing a state where the second link 11 is parallel to the transport path at the end point of the transport path when M <1.

FIG. 14 is a diagram showing a state where the second link 11 is parallel to the transport path at the end point of the transport path when M> 1.

FIG. 15 is a diagram showing various forms of a link mechanism of the carrying device.

FIG. 16 is a diagram showing a conventional transfer device using a link mechanism.

[Explanation of symbols]

1 Conveyor 2 Robot system 3 robots 9 Link mechanism 10 First link 11 Second Link 12 Holding means

Claims (8)

[Claims] 1. A transporting device comprising a retractable link mechanism and a holding means provided at a tip of the link mechanism for holding an object to be transported, wherein the link mechanism comprises a rotatable first link and a first link. The first link has a second link that is rotatably attached to the tip of the first link and has a length different from that of the first link, and during transport, the second link is rotated in synchronization with the rotation of the first link to form a link mechanism. A carrier device, wherein the holding means is moved in a substantially linear shape to be conveyed by expanding and contracting. 2. When the first link rotates, it has a driven follower for link which rotates the second link at a predetermined rotation ratio with respect to the rotation of the first link, so that the conveyance path becomes substantially straight. 2. The transfer device according to claim 1, wherein the rotation ratio of the driven follower rotation means for link is set. 3. The rotation ratio of the link driven rotation means is set such that the first link and the second link have a relationship of 180 ° at the start point or the end point of the transport path. Item 2. The transfer device according to item 2. 4. The moving path of the holding means is made closer to a straight line by stopping the first link and the second link by shifting a predetermined angle from 180 ° at the start point or the end point of the transport path, and the start point is shifted by the predetermined angle. 3. The transport device according to claim 2, wherein the rotation ratio of the driven rotation means for link is set so as to stop at the end point. 5. The rotation ratio of the link driven rotation means is set such that the first link is parallel to the transport path at the start point or the end point of the transport path.
The transport device described. 6. The rotation ratio of the link driven rotation means is set so that the second link is parallel to the transport path at the start point or the end point of the transport path.
The transport device described. 7. When the second link rotates, the holding means has a driven rotating means for rotating the holding means at a predetermined rotation ratio with respect to the rotation of the second link. 7. The transfer device according to claim 1, wherein the rotation ratio of the driven rotation means for holding means is set so as to be constant. 8. The transfer device according to claim 1, wherein a base end portion of the first link is attached to a wrist at a tip end of an arm of a robot.