JPH08281577A - Rotational drive structure of cylindrical coordinates robot - Google Patents

Abstract

PURPOSE: To reduce cost required for parts working and assembling. CONSTITUTION: A connecting means connecting together a revolving shaft 3 and a vertical shaft unit is constituted of the shaft part 3b of the revolving shaft 3, a cylindrical fitting part 26 provided on the plate 25 of the vertical shaft unit, a presser plate 46 fastening the shaft part 3b with the fitting part 26 by rotation-stop, and two bolts 47. A flat worked face 48 set according to the strength characteristic of the material constituting the shaft part 3b and transmitted torque is provided on the outer circumferential face of the shaft part 3b. The fitting part 26 is provided with a notch part 49 exposing the worked face 48 of the shaft part 3b in the condition of fitting around to the outer circumference of the shaft part 3b. The presser plate 46 is pushed into contact with the worked face 49 through the notch part 49 of the fitting part 26, and fixed to the fitting part 26 by fastening of the bolts 47, so as to obtain prescribed surface pressure between the worked face 48 and itself.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical coordinate type robot, and more particularly to a rotary drive structure for a rotary axis unit and a vertical axis unit.

[0002]

2. Description of the Related Art In a small cylindrical coordinate type robot, in a rotary drive unit which is connected to a rotary shaft and rotationally drives a vertical shaft unit, an inertial force or an external force applied to the vertical shaft unit causes a force between the rotary shaft and the vertical shaft unit. In order to prevent misalignment, it is necessary to fasten the rotation stop to the rotation axis. As a conventional technique related to the fastening of the detent, a method using a key and a method using a set screw are generally used.

[0003]

However, in the above-mentioned method of fixing the key, it is necessary to form a groove with high precision for adjusting the tightening margin between the key and the key groove, and also to actually align the key during assembly. Therefore, there is a problem that man-hours are required and cost is increased. Also,
The method using the set screw is cheaper and easier to adjust than the method using the key, but the tip surface of the set screw is crushed (buckled) due to repeated stress applied by the turning motion of the vertical axis unit. Since it may occur, it is difficult to use it for a rotary drive unit having a large transmission torque. The present invention has been made based on the above circumstances, and an object of the present invention is to reduce the cost for processing and assembling parts in a rotary drive structure of a cylindrical coordinate type robot.

[0004]

The present invention has the following features to attain the object mentioned above. In claim 1,
Cylindrical coordinate type robot provided with a turning shaft to which a rotation output of a drive motor is transmitted through a reduction gear, and a vertical shaft unit which is connected to the turning shaft via a connecting means and rotates integrally with the turning shaft. In the above, the connecting means is a shaft portion provided on one of the rotary shaft and the rotary body and coaxial with the rotary shaft, and a cylindrical fitting provided on the other side and fitted to the outer periphery of the shaft portion. A joint part, and a fastening means for fastening the shaft part and the fitting part, wherein the shaft part is provided with a flat processed surface on the outer peripheral surface, and the fitting part is provided on the outer periphery of the shaft part. A cutout portion that exposes the processing surface in a fitted state is provided, and the fastening means includes a pressing plate that is pressed against the processing surface through the notch portion, and the processing surface and the pressing plate. In order to obtain a predetermined surface pressure between The serial holding plate, characterized in that it consists of a fixing member for fixing to the fitting portion in a state pressed against the processing surface.

According to a second aspect of the present invention, in the rotary drive structure for a cylindrical coordinate type robot according to the first aspect, the shaft portion has the machined surfaces provided on both sides in the radial direction, and the shaft section is provided with respect to each machined surface. Each of the pressing plates is fixed to the fitting portion by the fixing member.

According to a third aspect of the present invention, in the rotary drive structure of the cylindrical coordinate type robot according to the first or second aspect, the shaft portion has the machined surface in accordance with strength characteristics and transmission torque of a material forming the shaft portion. The required area is set.

According to a fourth aspect of the present invention, in the rotary drive structure for a cylindrical coordinate type robot according to any of the first to third aspects, the fixing member can adjust a fastening force for fixing the pressing plate to the fitting portion. It is characterized in that it allows relative rotation between the shaft portion and the fitting portion when an excessive rotational force acts on the connecting means.

[0008]

[Operation and effect of the invention]

(Claim 1) In the connecting means for connecting the turning shaft and the vertical shaft unit, a shaft portion provided on either one of the turning shaft and the vertical shaft unit and a fitting portion provided on the other are fitted. In this state, the pressing plate pressed against the machined surface of the shaft part is fixed to the fitting part by the fixing member, so that the vertical shaft unit is fixed to the turning shaft while being prevented from rotating.
In this rotation drive structure, it is sufficient that the pressing plate can be fixed to the fitting portion against the processing surface, and it is not necessary to combine components having high dimensional accuracy. Therefore, compared with the case of the conventional detent fastening using a key, highly precise processing is not required, and therefore, actual product alignment processing at the time of assembly is also unnecessary.

(Claim 2) By providing the machined surface of the shaft portion on both sides in the radial direction, the overall area of the machined surface can be set large. As a result, a sufficient surface pressure can be secured between the processing surface and the pressing plate against the stress applied when the rotational force is transmitted, so that the shaft portion and the fitting portion (that is, the rotation axis and the vertical axis unit). ) Can be securely stopped and fastened.

(Claim 3) The machined surface provided on the shaft portion is added when the rotational force is transmitted by setting the required area in accordance with the strength characteristics of the material forming the shaft portion and the transmission torque. A necessary and sufficient surface pressure can be obtained for the stress.

(Claim 4) Since the fixing member can allow relative rotation between the shaft portion and the fitting portion when an excessive rotational force acts on the connecting means, an excessive rotational force applied to the connecting means. It is possible to allow the shaft portion and the fitting portion to rotate relative to each other without directly receiving them.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the cylindrical coordinate type robot of the present invention will be described below with reference to the drawings. Robot 1 of this embodiment
Is a base 2 as shown in FIG. 1 (overall perspective view of the robot 1) and FIG. 2 (overall view showing the internal structure of the robot 1).
Swivel shaft 3 rotatably supported with respect to (see FIG. 2),
A vertical shaft unit 4 connected to the swivel shaft 3 via a connecting means (described later), a horizontal shaft unit 6 assembled to the vertical shaft unit 4 via a slide block 5 (see FIG. 2), and a horizontal shaft unit. It is composed of four axes of the wrist swing shaft 7 assembled at one end (right end in FIG. 2) of the shaft unit 6, and drive motors 8 to 11 (FIGS.
(See reference) is a small cylindrical coordinate type robot.

The base 2 forms the basis of the entire robot and has a base 12 and a base housing 13.
The base base 12 houses the drive motor 8 inside and the outer periphery is covered by a base cover 14. Base 1
As shown in FIG. 9, three small projections 12b for supporting the robot 1 with respect to the installation surface G of the robot (see FIG. 8) are provided integrally with the base 12 on the bottom surface 12a of the robot 2. Has been. That is, the present robot 1 has a structure in which the small projections 12b are supported on the installation surface G at three points, and it is not necessary that the entire bottom surface of the base 12 be in close contact with the installation surface G.

The drive motor 8 is fixed at its upper end by bolts 16 to an annular plate 15 which is sandwiched between the base 12 and the base 13. The drive motor 8 is, for example, a low output motor having a capacity of 60w. Each drive motor 8 is attached to the base cover 14.
Connector 11 for connecting a power line (not shown) for supplying electric power to 11 to 11, and connector 18 for connecting a signal line (not shown) of an encoder (not shown) for detecting the rotation angle of each drive motor 8-11. , And a self-supporting cable 19 that is wired between the base 2 and the vertical axis unit 4.
A grommet 20 and the like (see FIG. 1) through which the grommet 20 passes are provided. It should be noted that the cable 19 has a single wiring to the drive motor 9, the drive motor 10, and the drive motor 11.

The base housing 13 is arranged on the plate 15, holds the reduction gear 21 coaxially with the output shaft 8a of the drive motor 8, and rotatably supports the swivel shaft 3 via a bearing 22. ing. The speed reducer 21 reduces the rotation speed of the drive motor 8 (for example, 1/100) and transmits the rotation speed to the swivel shaft 3. The speed reducer 21 is arranged between the drive motor 8 and the swivel shaft 3. It is fixed to the housing 13. The bearing 22 is the base housing 1
3 is held by a pressing plate 24 fixed to the upper end surface of the vertical shaft unit 3 and is provided with a plate 25 of the vertical shaft unit 4 via a fitting portion 26 (see FIGS. 6 and 7).
The thrust in the thrust direction is adjusted by the tightening amount of the nut 27 that is fastened to the shaft portion 3b.

The swivel shaft 3 is connected to an output shaft (not shown) of the speed reducer 21 and is rotatably supported by a bearing 22. The shaft 3a has a diameter smaller than that of the shaft 3a and extends above the shaft 3a. The shaft portion 3b and the shaft portion 3b project upward from the base housing 13. For the pressing plate 24, the base housing 13, and the plate 15, the bolt 28 is inserted from above the pressing plate 24, and the screw portion provided at the tip of the bolt 28 is fastened to the base base 12. As a result, the whole is fixed to the base 12.

The vertical axis unit 4 is assembled in an upright posture with respect to the base 2, and rotates together with the turning axis 3 to perform a turning operation. Both ends of the vertical axis unit 4 are supported in parallel by plates 25 and 29, respectively.
Number of slide shafts 30 and one ball screw 31, a ball screw nut 32 screwed to the ball screw 31, and a drive motor 9 for rotationally driving the ball screw 31 via a rotational force transmission means (described below) (see FIG. 3 and FIG. 4) and the like, and is entirely covered with a resin-molded cover 33 (see FIG. 1).

The two slide shafts 30 are provided with screw portions (not shown) at both ends, and nuts 34 and 35 are fastened to the screw portions from the outside of the plate 25 and the plate 29, respectively. Both ends of the slide shaft 30 are fixed to the plates 25 and 29. The ball screw 31 is located at the center of the two slide shafts 30, the lower end is rotatably supported by the plate 25 via a bearing (not shown), and the upper end is a bearing 36 (see FIGS. 3 and 4). ), And is rotatably supported by the plate 29.

The ball screw nut 32 is fixed to the slide block 5, and the ball screw 31 is attached to the drive motor 9.
By rotating under the rotational force of, the slide block 5 and the slide block 5 move in the vertical direction on the axis of the ball screw 31. As shown in FIGS. 5 and 6, the drive motor 9 is arranged below the plate 29 and is fixed to the plate 29 by four bolts 37 (see FIG. 5). In addition,
The drive motor 9 is a motor of the same type as the drive motor 8 of the swing shaft 3, and has a capacity of 60 w, for example.

As shown in FIGS. 3 and 4, the rotational force transmitting means has a rotating shaft 9 of the drive motor 9 above the plate 29.
A pulley 38 fixed to a, a pulley 39 fixed to the upper end of the ball screw 31 at the upper part of the plate 29, and a belt 4 drivingly connecting the pulley 38 and the pulley 39.
It consists of zero.

As shown in FIG. 8, a grommet 41 through which the cable 19 is routed between the cover 33 and the base 2 is provided at the lower portion of the side surface of the cover 33. A grommet 43 is provided to pass the self-standing cable 42 wired from the shaft unit 4 to the horizontal shaft unit 6. The cable 42 is a single wiring to the drive motor 10 and the drive motor 11.

Inside the cover 33, as shown in FIG. 10, one internal wiring 19a branched from the cable 19 is provided.
Is fixed to a stay 44 arranged inside the cover 33 by a clamp 45 or the like and connected to the drive motor 9. The stay 44 extends vertically inside the cover 33, and both ends thereof are fixed to the plate 25 and the plate 29, and together with the plates 25 and 29, a rigid body is formed. Also, the other wiring 19b branched from the cable 19
Is routed to the horizontal axis unit 6 as a cable 42 through the grommet 43.

Now, the above-mentioned connecting means will be described with reference to FIGS. 6 and 7. 6 is an exploded perspective view of the connecting means, and FIG. 7 is a sectional view of the fitting portion. The connecting means is
The rotary shaft 3 includes a shaft portion 3b, a fitting portion 26 provided on the plate 25 of the vertical shaft unit 4, a pressing plate 46 that holds the shaft portion 3b and the fitting portion 26 in a non-rotating manner, and two bolts 47. It On the outer peripheral surface of the shaft portion 3b,
As shown in FIG. 6, a flat processed surface 48 that receives a transmission torque between the pressing plate 46 is provided. The size of the machined surface 48 is set to a required area according to the strength characteristics and the transmission torque of the material (for example, steel) forming the shaft portion 3b (that is, the turning shaft 3).

The fitting portion 26 is provided at a position projecting to the side of the plate 25, and is provided in a cylindrical shape to be fitted on the outer circumference of the shaft portion 3b. Further, the fitting portion 26 includes the shaft portion 3
The processed surface 4 of the shaft portion 3b is fitted to the outer periphery of b.
A notch 49 that exposes 8 is provided. However, as shown in FIG. 7, the notch portion 49 has both end surfaces 49 in the circumferential direction.
The a is cut to a position slightly lower than the machined surface 48 so that the a does not protrude forward from the machined surface 48 of the shaft portion 3b. Further, screw holes 49b (see FIG. 6) for tightening the bolts 47 are provided on both end surfaces 49a of the cutout portion 49, respectively.

The holding plate 46 is provided such that its lateral width dimension (length in the left-right direction in FIG. 7) is larger than the diameter of the shaft portion 3b, and through holes 46a through which the bolts 47 are inserted are formed at both ends thereof. . The bolt 47 is a pressing plate 46.
Is pressed against the processed surface 48 of the shaft portion 3b, and is inserted through the through hole 46a of the pressing plate 46 to form the cutout portion 49.
Is fastened to the screw holes 49b provided on both end faces of the.
At this time, the shaft portion 3 is removed from both end surfaces 49a of the cutout portion 49.
Since the processed surface 48 of b is slightly protruded to the front, as shown in FIG. 7, both end surfaces 49 of the pressing plate 46 and the cutout 49 are formed.
A slight gap S is formed between the a and the a. This gives 2
When the bolt 47 is tightened, its fastening force does not act on both end surfaces 49a of the cutout portion 49, and the shaft portion 3
It can be received by the processed surface 48 of b.

The slide block 5 is a vertical axis unit 4
2 slide shafts 30 are slidably assembled through vertical slide bearings (not shown), and are also respectively attached to the two slide shafts 50 of the horizontal shaft unit 6 described later. It is slidably mounted via left and right slide bearings 51.

The horizontal axis unit 6 is a slide block 5
Is assembled to the vertical axis unit 4 through the vertical axis unit 4 and linearly moves in the vertical direction integrally with the slide block 5 with respect to the vertical axis unit 4. ) Perform a linear motion in the left-right direction. The horizontal axis unit 6 has two slide shafts 50, one end of which is supported by plates 52 and 53 and which are arranged in parallel, and one ball screw 54, and a ball screw nut 55 which is screwed to the ball screw 54. , A drive motor 10 (see FIG. 3 and FIG. 5) that rotationally drives the ball screw 54 via a rotational force transmitting means (described below), etc., and is entirely formed by a resin-molded cover 56 (see FIG. 1). (Including the drive motor 11 for the wrist swing shaft 7) is covered.

The two slide shafts 50 are formed with screw portions (not shown) at both ends, and nuts 57 and 58 are fastened to the screw portions from the outside of the plate 52 and the plate 53, respectively. Both ends of the slide shaft 50 are fixed to the plates 52 and 53. The ball screw 54 is located in the center of the two slide shafts 50, one end (the right end in FIG. 2) is rotatably supported by the plate 52 via a bearing 59, and the other end is Plate 53 through bearing 60
It is rotatably supported by.

The ball screw nut 55 is fixed to the slide block 5, and the ball screw 54 is attached to the drive motor 1.
When it receives a rotational force of 0 and rotates, it moves on the axis of the ball screw 54. However, since the ball screw nut 55 is fixed to the slide block 5 and its movement in the horizontal direction is restricted, in reality, the ball screw 54 (that is, the entire horizontal axis unit 6) does not move with respect to the ball screw nut 55. It will move horizontally.

As shown in FIG. 5, the drive motor 10 is arranged on one side of the plate 53 (on the wrist swing shaft 7 side) and is
It is fixed to the plate 53 by a book bolt 61 (see FIG. 4). The capacity of the drive motor 10 is, for example, 40w. As shown in FIGS. 4 and 5, the rotational force transmitting means includes a pulley 62 fixed to the rotary shaft 10 a of the drive motor 10 on the outside of the plate 53, and the plate 5 as well.
Pulley 6 fixed to the end of the ball screw 54 on the outside of 3
3, and a belt 64 drivingly connecting the pulley 62 and the pulley 63.

As shown in FIG. 1, a grommet 65 through which the cable 42 to be wired between the vertical shaft unit 4 and the vertical shaft unit 4 is passed is provided in a substantially central portion of the upper surface of the cover 56. Inside the cover 56, as shown in FIG. 11, one internal wiring 42a and the other internal wiring 42b branched from the cable 42 to the left and right are fixed to the stays 66 provided inside the cover 56 by the clamps 67 and the like. The one internal wiring 42a is connected to the drive motor 10, and the other internal wiring 42b is connected to the drive motor 11. Stay 66
Extends in the left-right direction inside the cover 56, and both ends thereof are fixed to the plate 52 and the plate 53, and together with the plates 52 and 53, form a rigid body.

As shown in FIG. 3, the wrist swing shaft 7 is rotatably supported by the plate 52 of the horizontal shaft unit 6 via a bearing 68, and a chuck (not shown) is provided at the tip (lower end in FIG. 3). Chuck attachment part 7 for attaching
a is provided. A gear 69 is integrally provided on the upper end portion of the wrist swing shaft 7, and is arranged so as to mesh with a gear 70 attached to the rotary shaft 11 a of the drive motor 11. The drive motor 11 is fixed to the plate 71 fixed to the plate 52 by tightening bolts 72 (see FIG. 5). The drive motor 11
Is a motor of the same type as the drive motor 10 of the horizontal axis unit 6, and has a capacity of 40 w, for example.

Next, the operation of this embodiment will be described. When the drive motor 8 rotates, the rotation speed of the drive motor 8 is reduced by the speed reducer 21, and the swing shaft 3 rotates at a low speed. By the rotation of the swivel shaft 3, the vertical shaft unit 4 connected to the swivel shaft 3 via the connecting means swivels around the swivel center A (see FIG. 8). As the drive motor 9 rotates, the vertical shaft unit 4 has its rotational force changed by the pulley 38, the belt 40,
The ball screw 31 is rotated by being transmitted to the pulley 39. As a result, the ball screw nut 32 screwed to the ball screw 31 moves up and down on the shaft of the ball screw 31 integrally with the slide block 5, and the horizontal shaft unit 6 supported by the slide block 5 becomes the vertical shaft unit 4. It works vertically.

In the horizontal shaft unit 6, when the drive motor 10 rotates, the rotational force of the drive motor 10 causes the pulley 6 to rotate.
2, the belt 64 and the pulley 63 are transmitted to the ball screw 5
4 rotates. Since the ball screw nut 55 screwed to the ball screw 54 is fixed to the slide block 5, the entire horizontal shaft unit 6 operates horizontally with respect to the vertical shaft unit 4. When the drive motor 11 fixed to the plate 52 of the horizontal axis unit 6 rotates,
The rotational force is transmitted to the gear 69 meshing with the gear 70, and the wrist swing shaft 7 rotates.

Next, the structural features of the robot 1 will be described. The vertical axis unit 4 and the horizontal axis unit 6 are
The drive motors 9 and 1 are used in order to make the shaft configurations common to each other.
Main components other than 0 are shared. In particular,
Ball screws 31 and 54, ball screw nuts 32 and 55,
Two slide shafts 30 and 50, plates 29 and 5
3, rotational force transmitting means (pulley 38, belt 40, pulley 39 and pulley 62, belt 64, pulley 63), bearings 36 and 60, stays 44 and 66, and the like use the same parts.

Further, the shape of the cover is made common by making the respective shaft configurations common. However, the horizontal axis unit 6
Since the cover 56 integrally covers the drive motor 11 of the wrist swing shaft 7, not all cover shapes are the same, and the cover 56 has the same shape except for the portion that covers the drive motor 11. . Further, as described above, the drive motor 8 and the drive motor 9, and the drive motor 10 and the drive motor 11 are of the same type.

In order to secure a good weight balance of the shaft units 4 and 6 with respect to the base 2, the following features are provided.
The vertical axis unit 4 and the horizontal axis unit 6 are, as shown in FIGS. 12 and 13, relative to a straight line C connecting the axis of the turning axis 3 (that is, the turning center A) and the axis B of the wrist turning axis 7. ,
They are offset from each other. Specifically, the offset amount of the vertical axis unit 4 and the offset amount of the horizontal axis unit 6 with respect to the straight line C are the same. In the horizontal axis unit 6, since the drive motor 11 for the wrist turning shaft 7 is provided at one end of the horizontal axis unit 6, the drive motor 10 for the horizontal axis unit 6 is attached to the drive motor 11 for the wrist turning axis 7. Plate 5
It is fixed to the plate 53 on the side opposite to 2 (see FIG. 5).

On the other hand, regarding the wiring of the robot 1, the wirings to the drive motor 9, the drive motor 10 and the drive motor 11 are unified, and the wiring is routed from the base 2 to the vertical axis unit 4 as a cable 19 to form the vertical axis unit. After branching wiring to the drive motor 9 inside 4, the remaining wiring, that is, the wiring to the drive motor 10 and the drive motor 11 is unified and wired as a cable 42 from the vertical axis unit 4 to the horizontal axis unit 6. . Further, inside the horizontal axis unit 6, after being pulled in from the substantially central portion of the upper surface of the cover 56, the cover 56 is branched in the left-right direction so that one internal wiring 42a is connected to the drive motor 10.
, And the other internal wiring 42b is connected to the drive motor 11, respectively.

Further, the cables 19, 42 are arranged with respect to the base 2, the vertical axis unit 4, and the horizontal axis unit 6 by arranging the respective axis units 4, 6 on the opposite sides with respect to the straight line C. It is connected as follows.
As shown in FIG. 14, the cable 19 wired between the base 2 and the vertical shaft unit 4 has a connection position to the vertical shaft unit 4 (position of the grommet 41) and a connection position to the base 2 (grommet 41). 20 positions) are offset from the turning center A of the vertical axis unit 4 to the opposite sides and wired. On the other hand, the cable 42, as shown in FIGS. 12 and 14, is connected to the vertical shaft unit 4 (grommet 4
3 position) is provided at a substantially central portion of the cover 33 in the vertical direction, and a connection position with the horizontal shaft unit 6 (position of the grommet 65) is provided at a substantially central portion of the cover 56 in the horizontal direction.

(Effect of this embodiment) In the robot 1 of this embodiment, the connecting means for connecting the revolving shaft 3 and the vertical shaft unit 4, that is, the rotary drive structure, is provided on the shaft portion 3b of the revolving shaft 3. Pressing plate 46 on surface 48
Is pressed and the pressing plate 46 is fixed to the fitting portion 26 fitted to the outer periphery of the shaft portion 3b with the bolt 47. According to this structure, a sufficient surface pressure can be obtained between the processed surface 48 and the pressing plate 46 with respect to the transmission torque of the swivel shaft 3, so that the fitting portion is engaged with the shaft portion 3b (that is, the swivel shaft 3). 26 (that is, the vertical shaft unit 4) can be securely fastened and fastened.

Further, in this rotary drive structure, the fitting portion 26
It is not necessary to form a pressing surface for the processed surface 48 of the shaft portion 3b on its own, and the pressing plate 46 separate from the fitting portion 26 is provided.
May be fixed to the fitting portion 26 with the bolt 47. That is, since it is not necessary to combine parts with high dimensional accuracy,
Compared with the conventional fastening method using a key, there is no need for highly accurate processing, and no actual product matching processing is required during assembly. This makes it possible to significantly reduce the number of man-hours in the parts processing and assembly process, and as a result,
The cost can be reduced.

Further, the plate 25 of the vertical axis unit 4
The fitting portion 26 provided on the side is provided with a cutout portion 49 on the side opposite to the vertical shaft unit 4 which is offset with respect to the turning center A (see FIGS. 3 and 4). Therefore, the workability when fixing the pressing plate 46 with the bolts 47 is good, and by any chance,
Even if an external force is applied to the robot 1 to loosen the fastening of the pressing plate 46, the robot 1 can be easily repaired by tightening the bolts 47 without disassembling the robot 1.

Vertical axis unit 4 and horizontal axis unit 6
Uses the same parts to share the shaft structure, so about 60% of the cover shape of the horizontal shaft unit 6
Can have the same shape as the cover of the vertical axis unit 4. As a result, 60% of the mold for resin molding the cover 56 can be shared with the cover 33, so that the cost of the mold can be reduced. Also, by using many identical parts, the purchase cost of parts can be reduced.

On the other hand, the drive motor 8 and the drive motor 9, and the drive motor 10 and the drive motor 11 are commonly used as the same type of motor, which is advantageous in maintenance and requires only two types of motors to be prepared. Even if something goes wrong, we can handle it. In this way, the cost can be significantly reduced by using a large number of the same parts to share the shaft configuration.

Further, in the horizontal shaft unit 6, the cable 42 routed from the vertical shaft unit 4 is drawn through the grommet 65 provided in the substantially central portion of the cover 56, and bifurcated symmetrically inside the cover 56. Is wired. Thus, when the robot 1 is suspended from the ceiling, the inlet (grommet 65) of the cable 42 is provided on the opposite side of the cover 56 as shown in FIG. Can be pulled inside. Therefore, when the robot 1 is suspended from the ceiling, the cable 42 does not hang downward, and it is not necessary to use parts such as stays for preventing the cable 42 from hanging down.

A base 2 having a vertical axis unit 4 and a horizontal axis unit 6 in which the same axis configuration is used in common by using many identical parts.
It is arranged in a good balance with respect to. That is, since the vertical axis unit 4 and the horizontal axis unit 6 are offset from each other with respect to the straight line C connecting the axis A of the turning axis 3 and the axis B of the wrist turning axis 7, Has a good weight balance. Further, in the horizontal shaft unit 6, the drive motor 10 is mounted on the side opposite to the drive motor 11 of the wrist swing shaft 7, so that the weight imbalance in the horizontal direction becomes small.

Further, by offsetting the mounting position of the cable 19 with respect to the base 2 and the vertical axis unit 4, when the vertical axis unit 4 turns, the maximum reaction force due to the bending of the cable 19 is maximized at both ends of the turning angle. Can be made smaller. In addition, the cable 42 is the vertical axis unit 4
And the horizontal axis unit 6 with the cover 3 respectively
Since they are attached to substantially the central portions of 3, 56, they can be brought close to the turning center A at both horizontal and vertical slide ends of the horizontal shaft unit 6. This allows
Since the reaction force due to the bending of the cable 42 can be reduced at both ends of the slide of the horizontal axis unit 6, the moment force from the turning center A due to the reaction force is reduced.

As a result, since the static and dynamic moments applied to the bearing 22 supporting the orbiting shaft 3 and the vertical slide bearing and the horizontal slide bearing 51 in the slide block 5 can be reduced, the bearing 22, the vertical slide bearing, and As the left and right slide bearings 51, low rigidity, low load and light weight can be used. As a result, the entire structure of the robot can be made light and compact, and high-speed operation is possible even with the low-output drive motors 8-11.

Further, the wirings to the drive motor 9, the drive motor 10, and the drive motor 11 are integrated into one cable 19
The wiring for the drive motor 10 and the drive motor 11 is integrated into a single cable 42, so that the wiring space of the entire robot can be reduced. As a result, the size of the entire robot including the wiring space can be reduced, and the installation space can be reduced. Further, since the cable 42 wired as described above can be set to the minimum required length, the total height of the robot 1 including the cable 42 can be suppressed even when the horizontal axis unit 6 is at the upper end of the slide.

By fixing the internal wiring of each axis unit 4 and 6 to the stays 44 and 66 provided inside the covers 33 and 56 respectively, the internal wiring is prevented from moving during the robot operation, and the wiring is rubbed or rubbed. It is possible to prevent disconnection. Further, the stays 44 and 66 are fixed at both ends to the plates 25 and 29 and the plates 52 and 53, respectively,
Since the plates 25 and 29 and the plates 52 and 53 form a rigid body, the rigidity during robot operation can be improved.

Since it is a lightweight and compact small-sized cylindrical coordinate type robot 1 using the low-output drive motors 8 to 11, for example, as shown in FIG. 16, a controller 73 for controlling the operation of the robot 1 and a controller 73. It is also possible to provide a pendant 74 for instructing the operation of the robot 1 via the, and use the outlet 75 connected to the controller 73 by inserting it into a general household 100V power source. In this case, since the drive motors 8 to 11 have a maximum capacity of 60 w, it is not necessary to take safety measures such as a safety fence.

As described above, since a general household 100V power source can be used as a power source of the robot 1, the installation location of the robot 1 is not specified. That is,
The robot 1 can be installed anywhere as long as the installation space can be secured. In addition, in the present embodiment, the small projections 12b are provided on the bottom surface 12a of the base 12 at three places and are supported at three points with respect to the installation surface G, so that it depends on the flatness of the installation surface G. Can be installed stably without

(Modification) In the connecting means of this embodiment, a flat machined surface 48 is provided on the outer peripheral surface of the shaft portion 3b.
This processing surface 48 does not need to be one surface, and the shaft portion 3
The processing surface 48 can be provided on the opposite side (that is, both sides in the radial direction) in the radial direction of b. Needless to say, the fitting portion 26 is provided with two notches 49 corresponding to the respective processed surfaces 48, and the pressing plate pressed against the respective processed surfaces 48 through the respective notched portions 49. 46 are fixed by bolts 47. In this case, the area of the machined surface 48 can be increased as compared with the above-described embodiment, so that more reliable detent fastening can be performed.

Instead of the bolt 47 for fixing the pressing plate 46 to the fitting portion 26, a fixing member capable of adjusting the fastening force to the fitting portion 26 is used, and when an excessive force acts on the connecting means, the shaft is By setting the fastening force so that the relative rotation between the portion 3b and the fitting portion 26 can be allowed, the relative rotation between the shaft portion 3b and the fitting portion 26 can be achieved without directly receiving an excessive force applied to the connecting means. You can escape.

In this embodiment, the rotating shaft 3 is provided with a shaft portion 3b.
And the fitting portion 2 on the plate 25 of the vertical shaft unit 4
6 is provided, the relationship between the shaft portion 3b and the fitting portion 26 may be reversed. That is, it is also possible to provide the fitting portion 26 on the swivel shaft 3 and the shaft portion 3b on the plate 25 to configure the connecting means.

Vertical axis unit 4 and horizontal axis unit 6
In the above, the rotations of the drive motor 9 and the drive motor 10 are transmitted to the ball screws 31 and 54 by belt drive, but the drive motor 9 and the drive motor 10 are arranged on the axis of the ball screws 31 and 54, respectively. The structure may be such that the rotational force is transmitted by a coupling or the like. Further, the vertical shaft unit 4 and the horizontal shaft unit 6 have a structure in which the two slide shafts 30 and 50 supported by the upper and lower slide bearings and the left and right slide bearings 51 are used as guides to perform a linear operation, but the LM guide (linear A structure in which a linear motion guide is received by a motion guide) may be used.

In this embodiment, the rotation of the drive motors 9 and 10 is converted into a linear motion by the combination of the ball screws 31 and 54 and the ball screw nuts 32 and 55. However, the drive motor 9 is driven by using a timing belt and a pulley. A structure in which rotation of 10 is converted into linear motion may be used.

The robot 1 according to this embodiment has a base 12
3 small protrusions 12b are provided on the bottom surface 12a of the
However, it is not always necessary to provide the small protrusions 12b integrally with the base 12, and as shown in FIG. 17, the bottom surface 12a of the base 12 is a flat surface. A washer 76 may be interposed between the bottom surface 12a and the installation surface G. In this case, the height of each washer 76 can be appropriately adjusted according to the flatness of the installation surface G. In the present embodiment, a specific example in which the robot 1 is supported at three points has been shown, but if the installation surface G is flat, the structure is supported by the entire bottom surface 12a of the base 12 (that is, the small protrusions 12b and Alternatively, the washer 76 may not be used).

[Brief description of drawings]

FIG. 1 is a perspective view showing the overall shape of a robot.

FIG. 2 is an overall sectional view showing an internal structure of a robot.

FIG. 3 is an overall view of the robot as viewed from the right side of FIG.

4 is an overall view of the robot as viewed from the left in FIG.

5 is an overall view of the robot viewed from above in FIG.

FIG. 6 is an exploded perspective view showing a connecting means of the robot.

FIG. 7 is a sectional view of a fitting portion.

FIG. 8 is a front view showing the appearance of the robot.

FIG. 9 is a plan view showing the bottom surface of the base base.

FIG. 10 is an overall view of a robot showing an internal structure of a vertical axis unit.

FIG. 11 is an overall view of a robot showing an internal structure of a horizontal axis unit.

FIG. 12 is a top view showing an arrangement relationship between a vertical axis unit and a horizontal axis unit.

FIG. 13 is a side view showing an arrangement relationship between a vertical axis unit and a horizontal axis unit.

FIG. 14 is a side view of the robot for explaining a cable wiring method.

FIG. 15 is an overall view showing a state where the robot is suspended from the ceiling and used.

FIG. 16 is an overall view of a robot when using a household power supply.

FIG. 17 is a diagram showing a support structure (modification) of the robot with respect to the installation surface.

[Explanation of symbols]

 1 Small Cylindrical Coordinate Robot 3 Swiveling Axis 3b Shaft 4 Vertical Axis Unit 8 Drive Motor 21 Reducer 26 Fitting Part 46 Holding Plate (Fastening Means) 47 Bolts (Fixing Member / Fastening Means) 48 Machining Surface 49 Notch

Claims (4)

[Claims] 1. A swivel shaft to which a rotational output of a drive motor is transmitted via a speed reducer, and a vertical shaft unit which is connected to the swivel shaft via a connecting means and rotates integrally with the swivel shaft. In the cylindrical coordinate type robot, the connecting means is provided on one of the turning axis and the vertical axis unit and is coaxial with the turning axis, and on the other side, the connecting means is fitted on the outer circumference of the shaft section. Cylindrical fitting part to fit,
And a fastening means for fastening the shaft portion and the fitting portion, the shaft portion is provided with a flat processed surface on the outer peripheral surface, and the fitting portion is fitted to the outer periphery of the shaft portion. A cutout portion that exposes the processing surface in a state, and the fastening means is a pressing plate that is pressed against the processing surface through the cutout portion, and a predetermined distance between the processing surface and the pressing plate. And a fixing member for fixing the pressing plate to the fitting surface in a state of being pressed against the processing surface so that the surface pressure can be obtained. 2. The rotary drive structure for a cylindrical coordinate type robot according to claim 1, wherein the shaft portion is provided with the processing surfaces on both sides in a radial direction, and the pressing plate is provided with respect to each of the processing surfaces. Is fixed to the fitting portion by the fixing member, respectively. 3. The rotary drive structure for a cylindrical coordinate type robot according to claim 1, wherein the shaft portion has a required area of the machined surface in accordance with strength characteristics and a transmission torque of a material forming the shaft portion. The rotation drive structure of the cylindrical coordinate type robot characterized in that 4. The rotary drive structure for a cylindrical coordinate type robot according to any one of claims 1 to 3, wherein the fixing member is provided so that a fastening force for fixing the pressing plate to the fitting portion can be adjusted. A rotary drive structure for a cylindrical coordinate type robot, wherein relative rotation between the shaft portion and the fitting portion is allowed when an excessive rotational force acts on the connecting means.