JPS59351B2 - industrial robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an industrial robot, and more particularly to an industrial robot that has flexible operation functions according to the work and has solved inertia and has high workability.

Conventional industrial robots are capable of performing repetitive tasks using a certain amount of force, but are unable to generate force that is tailored to the task or scope of work. For example, when inserting a wheel onto a shaft, the wheel held by the hand must be kept concentric with the center of the mounting shaft, otherwise the wheel cannot be reliably set on the mounting shaft. This is because, in a robot that repeats a fixed action using a fixed force as mentioned above, even if the robot moves out of position, the fixed force still acts on the work target, such as the mounting shaft or the wheel itself. may be damaged or even damage the robot. The present invention was created in view of the above viewpoint, and its purpose is to have a flexible movement function according to the work like a human muscle, and to have adaptability according to the diversification of the work content and work range. Therefore, we aim to provide an industrial robot that responds sensitively to external motion, can operate reliably even with the slightest external force, and further improves stability and reliability by preventing inertia. It is something. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of the entire industrial robot according to the present invention, and FIG. 2 is a partially cutaway side view of the same for explanation.

In the figure, reference numeral 1 denotes an arm mechanism having a parallelogram configuration, which is capable of three-dimensional movement such as back and forth, up and down, and rotation operations either singly or simultaneously, and is configured to maintain a weightless state during operation.

This arm mechanism 1 has its base end supported by side plates 2 and 3, and is configured to rotate approximately 360 degrees by its rotation mechanism 4, and is configured so that it can be installed on the ground with a pedestal 162 as shown in the figure. The installation method is arbitrary; for example, it can be installed on the ceiling, or it can be configured to run on the ground on a vehicle platform. The rotating mechanism 4 has a mounting plate 6 with its rotary servo actuator 5 mounted on the side plates 2 and 3 as shown in the third figure.
It is configured so that it is attached via the

The configuration of this rotary servo actuator 5 will be explained next. A drive motor 8, such as a DC servo motor, an AC induction motor, or a pulse motor, equipped with an electromagnetic clutch 7 is disposed within a cylindrical casing 6, and the base end is attached to the output shaft 9 to the bearing 11 of the cover 10. A control rotating shaft 12 is connected to a coupling 13 via a key 14, and a pulse encoder 15 is attached to the other end. Reference numeral 16 denotes a reduction gear provided at the base end of the control rotating shaft 12, which reduces the rotational drive of the drive motor 8 to a predetermined reduction ratio, reduces backlash, and achieves high-precision positioning that increases stopping accuracy. 17 is a circular spline, 18 is a flex spline, and 19 is a wave generator.

Reference numeral 20 denotes a driving rotating shaft whose base end is attached to the reduction gear 16 via a tightening bolt 21, and is disposed within a cover 23 attached to the tip of the casing 6 via a tightening bolt 22, and the control rotational shaft 20 The shaft 12 is the driving rotation shaft 2
Further, the tip of this drive rotation shaft 20 is attached to the attachment plate 6 of the side plates 2 and 3 via a tightening screw 24.

In a turning mechanism having such a configuration, the rotational drive shaft of the drive motor 8 and the control rotating shaft 12 provided with the pulse encoder 15 rotate while being reduced in speed to a predetermined reduction ratio, and the driving rotating shaft 20 also rotates in the same manner. It is slowing down and rotating.

Therefore, the pulse signal of the pulse encoder 15 is directly transmitted to the drive motor 8, and the drive motor 8 can be directly controlled.By increasing the reduction ratio, even if the electromagnetic clutch 7 is activated and the drive motor 8 is stopped, The backlash becomes extremely small, improving stopping accuracy and enabling highly accurate positioning. Next, the configuration of the arm mechanism 1 will be explained. This arm mechanism 1 has a parallelogram configuration so as to maintain balance in any operating position.

That is, an auxiliary arm 27 is interposed between the upper and lower arms 25 and 26 extending horizontally, and the base ends of the upper arm 25 and the auxiliary arm 8 are connected vertically to a link 28 between the side plates 2 and 3. , 28 via support shafts 29 and 30, respectively, and furthermore, the tips of the upper and lower arms 25 and 26 are tied vertically to a vertical arm 31 that hangs downward, and support shafts 32,
It is pivotally supported via 33.

Reference numeral 34 denotes a vertical auxiliary arm along the vertical arm 31, and a protruding piece 35 of the tip of the auxiliary arm 27 is pivoted to this via a support shaft 36, and is also pivoted to the vertical arm 31 via a support shaft 37. There is a vertical piece 38 between the support shafts 33 and 37.
is provided.

The arm mechanism 1 having such a configuration is configured to be able to move forward and backward and up and down within a certain range.

That is, the side plates 2 and 3 are provided with guide holes 39 and 40 in the vertical direction on the distal end side and in the horizontal direction on the upper end side, respectively,
These guide holes 39, 40 are provided with guide rails 41, 41 and 42, 42 along their longitudinal edges, respectively. A link 43 vertically connecting the base end of the auxiliary arm 27 and the lower arm 26 inside one of the guide holes 39 has a support shaft 44,
Rollers 47, 47 and 48, 48 provided at the upper and lower ends of a support 46 which is pivotally supported via a link 45 and further connected to this link 43 outside the guide hole 39 are connected to the guide rail 41,
41 in a slidable manner. 49 is a vertical movement mechanism connected to the support shaft 45 and configured to move the arm mechanism 1 in the vertical direction, which is regulated within the range of the guide hole 39, as shown in FIGS. 7 to 9. Although the upward movement of the arm mechanism 1 can be operated using various driving servo actuators, similar servo actuators are used in the forward and backward movement mechanism 50 described below. First, the longitudinal movement mechanism 50 will be explained.

The configuration of the forward and backward movement mechanism 50 of this arm mechanism 1 is as follows.

A support 51 whose one end is pivoted to the support shaft 29 of the link 28 inside the other guide hole 40 and an outer support 52 connected to this support 51 outside the guide hole 40. The front and rear rollers 53, 53 and 54, 54 are configured to be slidably fitted to the guide rails 42, 42. As described above, a driving servo actuator is attached to the vertical movement mechanism 49 and the longitudinal movement mechanism 50 to move the arm mechanism 1 in a predetermined direction. To explain the servo actuator 55 shown in FIG. 7, the base end of a pipe rod 58 is attached to a piston 57 disposed within a tube 56 of an air cylinder, and the tip extends from a rod flange 59 and is provided with a knuckle joint 60. .

Reference numeral 61 designates a bolt screw disposed within the pipe rod 58, the base end of which is screwed into a support 63 provided on the piston flange 62, and the base end is pivotally supported by a head flange 64.

The inside of the cylinder is thus divided into two chambers 65 and 66 by the piston 57 disposed within the tube 56, air pressure is injected and discharged from the air inlet and outlet (not shown), and the piston 57 is reciprocated to operate the pipe rod 58. , which generates a predetermined thrust. However, although air pressure generally produces a large thrust, it is difficult to make very slight position adjustments, that is, fine adjustments, due to sliding resistance of the piston 57, pressure fluctuations, etc. For this reason, it is difficult to use air pressure to improve positioning accuracy in robots. In consideration of this point, the servo actuator 55 is designed to allow fine adjustment.

A rotating shaft 67 connected to the base end of a bolt screw 61 disposed inside the pipe rod 58 extends below the head flange 64, a gear 68 is attached to this, and a transmission mechanism 71 consisting of gears 69 and 70 that sequentially mesh with this. A drive motor 74, such as a DC servo motor, an AC induction motor, or a pulse motor, is connected to one end of the rotating shaft 72 of the gear 70 on a mounting plate 73 provided on the head flange 64. An electromagnetic clutch 75 is attached to the rotating shaft 67, and a pulse encoder 76 is attached to the rotating shaft 67.
are connected. Servo actuator J model shown in Figure 8
V is characterized by the use of diaphragm 78,
The other configurations are the same as those in the previous embodiment.

The servo actuator 79 shown in FIG. 9 differs from the previous embodiment in that its bolt screw 80 is not installed inside the piston rod 81 but is attached to the outside of the cylinder, so that similarly highly accurate positioning can be expected. It is.

A support member 82 is attached to the tip of this piston rod 81 via a knuckle joint 60, and a bolt screw 80 is screwed into a support 84 provided on this support piece 83, with the base end of the bolt screw 80 facing the upper end of the tube 56. The bolt screw 80 is pivotally supported on a bearing part 86 of a support plate 85 attached to the
A gear 88 is attached to a rotating shaft 87 connected to the base end of the
A transmission mechanism 91 is provided by configuring gears 89 and 90 that mesh with this in sequence, and a drive motor 74 provided on a support plate 85 is connected to one end of a rotating shaft 92 of the gear 90, and an electromagnetic clutch 75 is connected to the other end. are connected. In addition, the rotating shaft 87
A pulse encoder 75 is connected to the drive motor 74 to control the drive motor 74. 93 is a guide rod that guides the support member 82, and 94 is a locking hole.

Such driving servo actuators 55, 77,
79 can drive the piston 75 with pneumatic pressure to operate the pipe rod 58 or the piston rod 81 and utilize the thrust, but when increasing the positioning accuracy, that is, when the arm mechanism 1 is For operation, the drive motor 74 is driven and the transmission mechanism 71,
91, the bolt screws 61 and 80 are driven by the rotational drive of the drive motor 74 that has been decelerated to a predetermined reduction ratio, and the piston 57 is slid through the supports 63 and 84 screwed thereto, thereby creating an arm mechanism. The forward and downward operations of 1 can be positioned extremely accurately, and the pulse encoder 7
Since the drive motor 74 can be controlled by the drive motor 74, its operation can be made more stable, and the backlash can be extremely small, making it possible to perform highly accurate positioning repeatability.

In addition, the servo actuator 55 attached to the vertical movement mechanism 49 utilizes air pressure, and the thrust generated by the servo actuator 55 is
This is used to maintain the arm mechanism 1 in a weightless state in response to the weight of the workpiece being held during work. The pipe rod 58 of the servo actuator 55 of the longitudinal movement mechanism 50 is connected to the rear end of the support 51 via a support shaft 95. Next, a balance mechanism 96 is constructed so that the vertical arm 31 and the second vertical arm 34 can maintain balance and work in a good condition no matter where they are moved to any position by the operation of the arm mechanism 1.

In other words, 97, 97 are the guide holes 42, 4 of the side plates 2, 3.
2 through the window hole provided below the auxiliary arm 27 as described above.
A support shaft 30 that pivotally supports the base end of the link 28, 28
Both ends of the cylinder extend from the window holes 97, 97, and piston rods 100 of cylinders 99, 99 provided on the outside of the side plates 2, 3 are connected to the extending ends 98, 98 via a knuckle joint 101. The cylinder 99 is configured to apply a vertical thrust to the arm mechanism 1 in response to the back and forth movement of the arm mechanism 1 so as to follow the movement and maintain balance with the vertical arm 31 at all times. That is, cylinder 99
, 99, rollers 106, 107 are provided at the tips of shaft rods 104, 105 extending to the side surfaces via supports 102, 103, respectively, at the lower end of the window hole 97. Two horizontal guide holes 108, upper and lower, provided in 3.
, 109 in a slidable manner, and furthermore, the cylinder 9
Roller 1 disposed on shaft rod 110 hanging from the lower end of roller 9
11 is slidably fitted into guide grooves 113 of guide rails 112, 112 provided on the side plates 2, 3. Therefore, by configuring the balance mechanism 96 as described above, the cylinders 99, 99 follow the links 28, 28 as the arm mechanism 1 moves back and forth, and move in the back and forth direction while always maintaining a vertical state. No matter what position the vertical arm 31 moves to, its thrust always acts in the vertical direction and can maintain proper balance. Furthermore, even if the lower end of the cylinder 99 is pivoted on the support shaft 114 as shown in FIG. Also, the thrust of the cylinder 99 acts in a substantially vertical direction, so that balance can be maintained.

Note that even if one of the guide holes 108 and 109 is omitted,
It is also possible to omit the cylinder 99 on one side. Therefore, there is no need to provide a balance weight as in the conventional case, and the balance with the vertical arm 31 can be maintained by this balance mechanism 96. Reference numeral 115 denotes an inertia prevention mechanism installed near this balance mechanism 96. This mechanism prevents inertia from occurring, especially when the workpiece is heavy, and enables work with increased stability and reliability. Specifically, reference numeral 116 denotes a plate-shaped body attached to the side surfaces of the side plates 2, 3 via fasteners 117, 117, . . . so as to cover almost the entire surface of the window hole 97. 1
16, the protruding shafts 119, 119 are attached to the extending ends 98, 98 of the support shaft 30 integrally or via metal fittings 118, and the joints 120, 120, such as ball bearings, are always in contact with the tips of the protruding shafts 119, 119. There is.

Therefore, since the joints 120, 120 serve as moving fixed points, there is no inertia caused by rotation, and this has the effect of increasing stopping accuracy even under large loads. Note that the space between the side plates 2 and 3 is wide, the balance mechanism 96 is disposed within the side plates 2 and 3, and the zygote 120 is placed between the side plates 2 and 3.
, 3, a similar effect can be expected. Next, the hand mechanism 121 that holds the water will be explained. This hand mechanism 121 is connected to the arm mechanism 1.
122 is a fixture, and this fixture 122 has a mechanism 124 for integrally rotating the hand part 123 and a workpiece mounting part 125. It is composed of a mechanism 126 that moves upward and a mechanism 127 that rotationally drives only the workpiece mounting portion 125, and this structure will be explained in sequence below.

The mechanism 124 that integrally rotates the hand portion 123 includes a reduction gear device 131 attached to the output shaft 130 of a drive motor 129, such as a DC servo motor, an AC induction motor, or a pulse motor, equipped with an electromagnetic clutch 128. Attach the drive rotating shaft 132 to the tip of the 131,
The configuration is such that the rotation of the drive motor 129 is reduced to a predetermined reduction ratio to reduce backlash and enable highly accurate positioning.

The structure of this speed reducer 131 is the same as that used in the turning mechanism 4, and consists of a circular spline 133, a flex spline 134, and a wave generator 135, and 136 is a cover, the tip of which is connected to the attachment 122.
138 is the output shaft 132.
It is a gear installed at the tip of the If this gear 138 is engaged with a gear 140 provided on a drive motor 139 with an electromagnetic clutch of a mechanism 126 that moves the workpiece attachment part 125 up and down at the tip of the fixture 122, the hand part 123 will be rotationally driven.

Furthermore, the mechanism 126 that moves downward has a reduction gear 142 similar to the one described above attached to the output shaft 141 of a drive motor 139 equipped with an electromagnetic clutch, a drive rotating shaft 143 attached to the tip thereof, and its bearing case 144 held. It is attached to the tool 145.

146 is a gear provided at the tip of the rotating shaft 143, and this gear 146 meshes with a gear 150 at the base end of the driving rotating shaft 149, which is supported by a bearing 148 provided at the mounting portion 14r of the holder 145. A bevel gear 151 is attached to the tip of this rotating shaft 149, and one end of the supporting shafts 153, 153 is attached to the side surface of the holder 145 through bearings 152, 152 perpendicular to this rotating shaft 149. A bevel gear 154 that meshes with the bevel gear 151 is attached to the bevel gear 154.

The other end portions of the support shafts 153, 153 are attached to a case 156 of a drive motor 155 of a rotational drive mechanism 127 of a workpiece mounting portion, which will be described later. Therefore, the rotational drive of the drive motor 139 in the workpiece mounting portion 126 is reduced by the reduction gear device 142 according to a predetermined reduction ratio, and the rotating shaft 143, gear 144,
150, by bevel gears 151 and 154 that are transmitted to and mesh with the rotating shaft 149, the workpiece mounting portion 125 moves up and down using the supporting shafts 153 and 153 as fulcrums. Next, the mechanism 127 for rotationally driving only the workpiece mounting part 125 is constructed by disposing a drive motor 155 with an electromagnetic clutch inside the case 156 to which the support shafts 153, 153 are attached as described above, and the output shaft of this drive motor 155. At 157, a reduction gear 158 is installed in the same manner as above.
A workpiece mounting portion 125 is formed at the tip of the workpiece mounting portion 125, and the rotational drive reduced to a predetermined reduction ratio is transmitted to the workpiece mounting portion 125, allowing the workpiece mounting portion 125 to be rotationally driven with high precision. 159 is a cover of the case 156.

In the industrial robot of the present invention having the above configuration, even if the support shaft 45 moves up and down within the guide hole 39, as is clear from the action explanatory diagram shown in Figure 12, △ABC and △ADE are always maintained. As long as they maintain similar shapes, the arm mechanism 1 can maintain balance, and if there is a load, the load and balance can be accurately maintained by a vertical thrust greater than the air pressure of the servo actuator 55 as described above. , which allows you to work in a zero-gravity state.

To explain the current usage state, as shown in FIGS. 13 and 14, the shaft 160 is gripped by the workpiece attachment part 125 of the hand mechanism 121 of the arm mechanism 1 which is maintained in a zero gravity state,
Assuming that the shaft 160 is misaligned with respect to the wheel 161, the angle arm mechanism 1 is rotated by the θ-axis movement, that is, the rotation mechanism 4, and the servo actuator 5 is rotated.
The clutch 7 is released, and the arm mechanism 1 is moved forward by the X-axis movement mechanism 50.
to keep it concentric with the center of the mounting shaft 161,
When the clutch 75 of the servo actuator 55 is released and the servo actuator 55 is released, the arm mechanism 1 and the shaft 160 are moved automatically. lower and insert it.

In this case, if the pneumatic thrust of the servo actuator 55 is equal to the weight of the arm mechanism 1, the arm mechanism 1 remains stationary. In other words, it is in a free state. Further, the insertion force can be selected by non-releasable pressure adjustment at the time of insertion. In addition, even if the clutch is released or driven using air pressure, the vertical movement is constantly controlled by the pulse encoder 76, and the positional relationship between the shafts, wheels, or robots is constantly controlled by the pulse encoder 76. There is no damage to the main body. With the above configuration, the present invention can work in a zero gravity state, has a flexible operation function, is highly adaptable, and therefore responds sensitively to external motion, eliminates damage to parts, and prevents inertia. It is a stable and reliable industrial robot.

[Brief explanation of drawings]

Fig. 1 is a side view of the entire industrial robot of the present invention, Fig. 2 is a partially cutaway side view of the same, Fig. 3 is a sectional view of the swing mechanism, Fig. 4 is a sectional view of the main parts, and Fig. 5 The figure is a sectional view of another embodiment of the main part, FIG. 6 is a sectional view with a part of the main part cut away, and FIGS. 7 to 9 are a sectional view of each embodiment of the servo actuator. A sectional view, FIG. 10 is a side view of the main parts of the hand part,
FIG. 11 is a sectional view of the same, FIG. 12 is an explanatory diagram of the operation, and FIGS. 13 and 14 are explanatory diagrams of the state of use. 1... Arm mechanism, 2, 3... Side plate,
4... Rotating mechanism, 49... Vertical movement mechanism, 50... Back and forth movement mechanism, 121... Hand mechanism.

Claims (1)

[Claims] 1. A vertical arm having a hand mechanism that can be operated independently or simultaneously in at least three axial directions is connected to the upper ends of a vertical arm and a second vertical arm, each of which is provided at the lower end thereof, to each end of an upper and lower arm and an auxiliary arm that extend in the horizontal direction; The base moving parts of the upper and lower arms and the auxiliary arm are equipped with a pulse encoder that is directly connected to the drive motor, and a control rotary shaft equipped with a reduction gear is installed inside the drive rotary shaft, and a turning mechanism that is linked to this rotary shaft is installed. The upper and lower arms are supported by a side plate provided with an arm mechanism, and the upper and lower arms have a longitudinal movement mechanism that restricts movement in the horizontal direction, and the auxiliary arm and the lower arm have vertical movement mechanisms that restrict movement in the vertical direction. A bolt screw is screwed into the pipe rod connected to the piston of the cylinder from the proximal end side so that it can move forward and backward, and a motor is connected to the bolt screw through a transmission mechanism. , a driving servo actuator equipped with a device for detecting the amount of movement of the pipe rod is connected to each other, and the thrust of the cylinder is always applied in the vertical direction to a link vertically connecting the upper arm and the auxiliary arm. A balance mechanism is provided, and the joint of the protruding shaft integrated with or connected to the lower support shaft of the link constitutes an inertia prevention mechanism capable of abutting against a plate-shaped body provided on the outside of the side plate. robot.