JPWO2017141833A1 - Table drive device and work system equipped with the table drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drive a movable table with high accuracy and high speed by coordinating two rotational drive sources.
[Solution]
The base 10, the first rotating shaft 21 that is directed to the first direction along the upper surface of the base 10 and supported by the base 10, and the upper surface of the base 10, and intersects the first direction. A second rotating shaft 31 that is directed in the second direction and supported by the base 10, and first and second rotations that are supported by the base 10 so as to transmit a rotational force to the two rotating shafts, respectively. And a movable table 40 supported by the base 10 so as to move in the first direction and the second direction above the two rotary shafts 21 and 23. Are driven in the XY directions by the first and second rotational drive sources 20 and 30 and the rack and pinion mechanism.
[Selection] Figure 1

Description

  The present invention relates to a table driving device that is incorporated in, for example, an industrial robot or the like and moves in two intersecting directions with high accuracy, and a work system including the table driving device.

Conventionally, for example, when automatically assembling a gear head (transmission gear unit) attached to a very small motor of φ10 mm or less using a robot, highly accurate position control is required so that the error with respect to the target is 20 μm or less. Become.
On the other hand, the robot may be difficult to perform precise positioning work required for assembling the gear head due to mechanical errors, measurement errors of angle sensors, flexibility and elasticity of arms and end effectors, and the like. Therefore, it is proposed that a precise positioning operation can be performed by using a table driving device capable of highly accurate position control in combination with a robot.
Conventional planar drive mechanisms include sliding screws, ball screws, rack and pinions, belts, chains, etc., mechanisms that convert rotational motion into linear motion, or fluid linear motion mechanisms such as pneumatic cylinders and hydraulic cylinders, linear motors It is well-known that it has a mechanism that directly moves linearly, such as an ultrasonic linear motion motor, and that two tables that drive on one axis are stacked in two stages so that the drive directions are orthogonal to each other. (For example, refer to Patent Document 1).
According to such a conventional technique, the movable table can be moved in two directions along a plane or stopped at a predetermined position by a combination of a uniaxial linear motion mechanism having a relatively simple structure. Therefore, for example, if a work is placed on the table driving device, the work is moved precisely, and the work is processed by a robot, there is a possibility that the work can be processed with high accuracy.

Japanese Patent Laid-Open No. 6-43939

By the way, for example, when the workpiece is a mass-produced product such as a gear head, and the gear head is assembled by the robot, it is required to shorten the work time as much as possible. Also, in order to compensate for high accuracy in automatic assembly using a robot, it is necessary to finely drive the planar drive table so as to follow disturbance or vibration at the natural frequency of the arm due to the movement of the robot itself. In some cases.
However, when the conventional table driving device is used, the other linear motion mechanism is overlapped and assembled on one linear motion mechanism, and therefore the one linear motion mechanism on the lower side has the uppermost portion. The weight of the other linear motion mechanism is added to the weight of the object to be transported placed on the table.
Therefore, the weight is unbalanced between the one linear motion mechanism on the lower side and the other linear motion mechanism on the upper side, and it is difficult to operate these two linear motion mechanisms having different weights in cooperation at high speed. It is.
For this reason, the lower one linear motion mechanism requires a larger driving force than the other upper linear motion mechanism, and the specifications differ between the upper and lower linear motion mechanisms, making the control complicated. Or may cause a decrease in productivity.
Furthermore, since the other linear motion mechanism on the upper side also moves a drive source (for example, an electric motor or a fluid motor), a cable for supplying power or a control signal to the drive source, a hose for supplying fluid, or the like The structure needs to follow the movement, but such a structure may reduce wear resistance, durability, and the like.

In view of such problems, the present invention has the following configuration.
A base, a first rotating shaft directed in a first direction along the upper surface of the base and supported by the base, and a second rotating along the upper surface of the base and intersecting the first direction A second rotating shaft directed to the base and supported by the base, and first and second rotational driving sources supported by the base so as to transmit rotational force to the two rotating shafts, respectively. A movable table supported by the base so as to move in the first direction and the second direction above the two rotation shafts, and the first rotation shaft and the second rotation shaft. The rotary shaft includes a first pinion having a length corresponding to the amount of movement of the movable table in the first direction and a length corresponding to the amount of movement of the movable table in the second direction. Of the first pinion and the second pinion are provided so as to be integrally rotatable. The first rack and the second rack are fixed so as to mesh with the first pinion and the second rack, respectively, and the first rack and the second rack mesh with the first pinion and the second pinion, respectively. In the state, it is provided to move in the tooth width direction.

  Since the present invention is configured as described above, the movable table can be driven with high accuracy and high speed by coordinating the two rotational drive sources.

It is a perspective view which shows an example of the table drive device which concerns on this invention. It is a disassembled perspective view of the same table drive device. It is a top view of the table drive device. It is a top view which shows the state which excluded the movable table and the rack in the same table drive device. It is a side view showing an example of a work system.

One of the features of the table driving device of the present embodiment is that the base, the first rotating shaft that is directed to the first direction along the upper surface of the base and supported by the base, and the base And a second rotating shaft supported by the base and directed in a second direction intersecting the first direction, and transmitting the rotational force to each of the two rotating shafts. First and second rotational drive sources supported by a table, and a movable table supported by the base so as to move in the first direction and the second direction above the two rotation shafts A first pinion having a length corresponding to the amount of movement of the movable table in the first direction, and the movable table on the first rotating shaft and the second rotating shaft, respectively. And a second pinion having a length corresponding to the amount of movement in the second direction are provided so as to be integrally rotatable. The first rack and the second rack are fixed to the movable table so as to mesh with the first pinion and the second pinion, respectively, and the first rack and the second rack are Each is provided so as to move in the tooth width direction while meshing with the first pinion and the second pinion (see FIGS. 1 to 4).
According to this configuration, the two pinions with different directions fixed to one movable table are directly engaged with the corresponding pinions, and each pinion is rotated by the rotation drive source. Compared with the prior art in which the upper and lower two tables are driven by the driving source, the load imbalance applied to the two rotary driving sources can be reduced. In addition, since the two rotational driving sources are supported on the same base, it is easy to fix cables, hoses and the like that supply power to these rotational driving sources.

  As another feature, in order to stably support the movable table, the base is provided with a movable support that supports the movable table so as to be movable in two directions, the first direction and the second direction. A mechanism is provided (see FIGS. 2 and 4).

  As another feature, in a particularly preferable aspect, the movement support mechanism includes a first rail fixed to the base along the first direction, and a movement guided by the first rail. A movable table, and a second rail fixed to the movable table along the second direction, and the movable table is guided and moved by the second rail. (See FIG. 2).

  As another feature, in order to further reduce the unbalance of the load applied to the two rotational drive sources, the smaller one of the load received from the movable table of the first rotary shaft and the second rotary shaft is selected. A weight body was provided on the rotating shaft (see FIGS. 1 to 4).

  As another feature, the work system is configured by including the table driving device and the robot (see FIG. 5).

<Specific Embodiment>
Next, specific embodiments having the above characteristics will be described in detail with reference to the drawings.
As shown in FIGS. 1 to 4, the table driving device A includes a base 10, a first rotating shaft 21 facing in a first direction (X direction) along the upper surface of the base 10, and the same base A second rotating shaft 31 that extends along the upper surface of the table 10 and is orthogonal to the first direction, and first and second rotational drive sources 20 and 30 that transmit rotational force to the two rotating shafts 21 and 31, respectively. A movable table 40 that moves in the first direction and the second direction above the two rotating shafts 21 and 31, and the movable table 40 moves in the first direction and the second direction. The movable support mechanism 50 which supports freely and the weight body 60 fixed to the 1st rotating shaft 21 are comprised, and the movable table 40 is driven to two directions of the said 1st direction and the said 2nd direction.

  The base 10 is a flat plate member whose upper and lower surfaces are substantially flat, and is formed in a rectangular plate shape according to the illustrated example. The base 10 is appropriately provided with holes, protrusions, and the like for fixing and fixing the first and second rotational drive sources 20, 30 and the movement support mechanism 50.

The first and second rotary drive sources 20 and 30 are two rotary electric motors with the same output, and for example, a stepping motor that controls the rotation angle of the output shaft may be used.
The first and second rotary drive sources 20 and 30 are arranged so that the axial directions are orthogonal to each other (see FIGS. 3 and 4), and the casings 22 and 32 are supported by the base 10 in a stationary manner.
The first rotary shaft 21 and the second rotary shaft 31 are concentric with the rotary shafts of the first and second rotary drive sources 20 and 30 via shaft couplings 24 and 34 (couplings), respectively. It is connected to the.

Each of the first rotating shaft 21 and the second rotating shaft 31 is formed in a cylindrical shaft shape at both ends in the axial direction, and is rotatable with respect to the base 10 via the pivot brackets 1 and 2, respectively. It is supported (see FIGS. 2 to 4).
A first pinion 23 and a second pinion 33 are provided on the first rotating shaft 21 and the second rotating shaft 31 so as to be rotatable integrally with each other near the center excluding the shaft support portions on both ends. It is done.

Each of the first pinion 23 and the second pinion 33 is formed in a spur gear shape, and each tooth portion on the outer periphery thereof extends in a long straight line shape parallel to the axis (see FIG. 4).
The first pinion 23 and the second pinion 33 are formed by processing (including cutting and forging) the outer peripheral portions near the center of the first rotating shaft 21 and the second rotating shaft 31, respectively. ing. As another example, it is also possible to adopt a mode in which a separate pinion is annularly fitted to the outer peripheral portion near the center of the first and second rotating shafts 21 and 31 formed in a shaft shape.

The lengths in the axial direction of the first pinion 23 and the second pinion 33 are respectively the amount of movement of the movable table 40 in the first direction (X direction) and the amount of movement in the second direction (Y direction). It is set accordingly.
More specifically, the first pinion 23 is formed slightly longer than the set movement amount of the movable table 40 in the first direction (X direction). The second pinion 33 is formed slightly longer than the set movement amount of the movable table 40 in the second direction (Y direction).
The set movement amount is a movement amount of the movable table 40 set in advance according to the specification of the table driving device A or the like.

The movable table 40 is located above the first pinion 23 and the second pinion 33 and is supported by the base 10 via a movement support mechanism 50 described later.
As illustrated in FIG. 1, the movable table 40 includes a substantially rectangular plate-shaped main body piece 40a having a flat upper surface, and a first rack support piece that protrudes horizontally from one side of the main body piece 40a. 40b and the 2nd rack support piece part 40c which protrudes in the horizontal direction from the other one side of the main-body piece part 40a are integrally formed (refer FIGS. 1-3).

A first rack 41 is fixed to the lower surface of the first rack support piece 40b of the movable table 40 along the second direction (Y direction).
A second rack 42 is fixed to the lower surface of the second rack support piece 40c in the movable table 40 along the first direction (X direction) (see FIGS. 1 and 2).

The tooth width (X-direction width) of the first rack 41 is set to be smaller than the axial length of the first pinion 23. The length of the first rack 41 in the Y direction is set slightly longer than the set movement amount according to the set movement amount of the movable table 40 in the second direction (Y direction).
Therefore, the first rack 41 is movable in the first direction (X direction) along the first pinion 23 in a state of being engaged with the first pinion 23.

Similarly, the tooth width (Y direction width) of the second rack 42 is set to be smaller than the axial length of the second pinion 33. The length of the second rack 42 in the X direction is set slightly longer than the set movement amount according to the set movement amount of the movable table 40 in the first direction (X direction).
Therefore, the second rack 42 is movable in the second direction (Y direction) along the second pinion 33 in a state of being engaged with the second pinion 33.

The movement support mechanism 50 includes first rails 51 and 51 fixed to the upper surface of the base 10 along a first direction (X direction), and a movement base 52 that moves while being guided by the first rail 51. And two second rails 53 and 53 fixed to the upper surface of the movable table 52 along the second direction (Y direction).
Then, the movable table 40 is fitted to the second rails 53 and 53 so as to move in the second direction (Y direction) on the upper side.
According to the illustrated example, the first rail 51 and the second rail 53 use an LM guide (linear motion guide) in which a concave movable portion is fitted to a linear guide rail. The concave movable part is fixed to the upper member (moving table 52 or movable table 40).

  The weight body 60 is a cylindrical member having an outer diameter larger than that of the first rotating shaft 21, and the load received from the movable table 40 among the first rotating shaft 21 and the second rotating shaft 31 is small. It is fixed to one rotation shaft (first rotation shaft 21 in the illustrated example) so as to be concentric and integrally rotatable, and functions as a counterweight.

More specifically, in the illustrated example, when the movable table 40 is moved in the first direction (X direction), the mass of the object moving at this time is the movable table 40, the first rack 41, and the second This is the total mass of the rack 42, the movable table 52, the second rails 53, 53, etc. (see FIG. 2).
On the other hand, when the movable table 40 is moved in the second direction (Y direction), the mass of the object moving at this time is such that the movable table 40, the first rack 41, the second rack 42, etc. The total mass (see FIG. 2), which is smaller than the former.
Therefore, according to this embodiment, the load received from the movable table 40 is smaller on the first rotating shaft 21 than on the second rotating shaft 31. For this reason, the weight body 60 is fixed to the first rotary shaft 21 to reduce the unbalance of the load applied to the first rotary drive source 20 and the second rotary drive source 30.

  The table driving device A having the above-described configuration, if necessary, includes a position sensor (not shown) that detects the position of the movable table 40 in the X direction and the Y direction, the first and second rotary drive sources 20, 30 is provided with a control circuit (not shown) for controlling 30.

Next, the working system S provided with the table driving device A having the above configuration will be described (see FIG. 5).
In this work system S, the table driving device A and the robot B are placed on the same surface.
A workpiece W is placed on the movable table 40 of the table driving device A. The workpiece W is, for example, a gear head assembly that is attached to a very small motor.

  The robot B includes a plurality of arms b4 connected to a support rod b2 fixed on the base b1 by joints b3, and a working unit b5 (end effector) that performs work on the distal end side of these arms b4. The operation is performed by bending / extending / rotating the arm b4, opening / closing / rotating the working part, etc., using a power source (not shown) such as a stepping motor included in the base b1, the support rod b2, the arm b4, etc. as power. I do.

Hereinafter, the characteristic operation and effects of the table driving device A and the work system S having the above-described configuration will be described.
According to the table driving device A, the single movable table 40 is directly driven by the first and second rotary drive sources 20 and 30 without interposing an intermediate table or the like. The unbalance of the load applied to the two rotational drive sources 20 and 30 is relatively small, and the unbalance is also reduced by the weight body 60.
Therefore, it is possible to use a drive source having substantially the same output for the two first and second rotary drive sources 20 and 30 and to move the first and second rotary drive sources 20 and 30 in cooperation with each other. Can be operated at high speed.
For this reason, it is possible to perform high-speed assembly work and processing with high positioning accuracy on the work W placed on the movable table 40 by the robot B.
In addition, since the first and second rotary drive sources 20 and 30 are supported on the same base 10, fixing of cables and the like for supplying power to the first and second rotary drive sources 20 and 30 is also possible. Therefore, durability of the table driving device A and the work system S can be improved.

  In addition, according to the said embodiment, although the electric motor was used as the 1st and 2nd rotational drive sources 20 and 30, as another example, the 1st and 2nd rotational drive sources 20 and 30 are made into a fluid motor. A substituted mode is also possible.

  Moreover, according to the said embodiment, the output shaft of the 1st and 2nd rotational drive sources 20 and 30 is respectively connected to the 1st rotating shaft 21 and the 2nd rotating shaft 31 via the shaft couplings 24 and 34. Although connected, as another example, the output shafts of the first and second rotary drive sources 20 and 30 may be used as the first rotary shaft 21 and the second rotary shaft 31, respectively. Is possible. In this embodiment, the first and second pinions 23 and 33 may be provided on the output shafts of the first and second rotational drive sources 20 and 30 respectively.

  According to the above embodiment, the movement support mechanism 50 having the above-described configuration is provided as a particularly preferable example. However, as another example, the movement support mechanism 50 is omitted, and the lower end side of the movable table 40 is slid onto the upper surface of the base. A mode in which the movable table 40 is freely moved in the horizontal direction by contact, or a repulsive magnet is provided between the base 10 and the movable table 40, and the movable table 40 is magnetically levitated and moved freely in the horizontal direction. It is also possible to adopt an aspect or the like.

  Moreover, according to the said embodiment, although the table drive apparatus A and the robot B were provided on the same surface, the work system S was comprised, As another example of this work system S, the movable table 40 of the table drive apparatus A is used. It is also possible to have a mode in which the robot B is placed on the workpiece W and the workpiece W placed on a portion other than the table driving device A is processed by the robot B.

  Further, as another example of the work system S, the robot B is replaced with a painting robot, a machining robot, a welding robot, a measuring instrument for measuring the position and state of the workpiece W, and the robot and measurement. It is also possible to adopt an embodiment in which a vessel or the like is used in appropriate combination.

  Furthermore, as another example of the work system S, it is possible to configure a medical work system (including a treatment system and an inspection system) by replacing the robot B with a medical device.

  Further, the present invention is not limited to the above-described embodiments, and can be appropriately changed without changing the gist of the present invention.

DESCRIPTION OF SYMBOLS 10: Base 20: 1st rotational drive source 21: 1st rotational shaft 30: 2nd rotational drive source 31: 2nd rotational shaft 40: Movable table 50: Movement support mechanism 51: 1st rail 52 : Moving platform 53: Second rail 60: Weight body A: Table driving device B: Robot S: Work system W: Workpiece

Claims (5)

A base, a first rotating shaft directed in a first direction along the upper surface of the base and supported by the base, and a second rotating along the upper surface of the base and intersecting the first direction A second rotating shaft directed to the base and supported by the base, and first and second rotational driving sources supported by the base so as to transmit rotational force to the two rotating shafts, respectively. A movable table supported by the base so as to move in the first direction and the second direction above the two rotation shafts,
The first rotating shaft and the second rotating shaft include a first pinion having a length corresponding to the amount of movement of the movable table in the first direction, and the second pin of the movable table. A second pinion having a length corresponding to the amount of movement in the direction of
A first rack and a second rack are fixed to the movable table so as to mesh with the first pinion and the second pinion, respectively.
The first rack and the second rack are provided so as to move in the tooth width direction while being engaged with the first pinion and the second pinion, respectively. Drive device.   The table according to claim 1, wherein the base is provided with a moving support mechanism that supports the movable table so as to be movable in two directions of the first direction and the second direction. Drive device. The moving support mechanism includes a first rail fixed to the base along the first direction, a moving table guided and moved by the first rail, and the second direction. A second rail fixed to the movable table,
The table driving device according to claim 2, wherein the movable table is provided so as to move while being guided by the second rail.   4. The weight body is provided on a rotary shaft having a smaller load received from the movable table among the first rotary shaft and the second rotary shaft. 5. Table drive device.   A work system comprising the table driving device according to claim 1 and a robot.

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