JPH08126989A - Rotation regulating mechanism of rotary shaft of articulated robot - Google Patents

Abstract

PURPOSE: To provide a rotation regulating mechanism of the rotary shaft of an articulated robot which can regulate the rotation of the rotary shaft in a specific scope more than one rotation, as well as can rotate one rotation or more, in a simple structure. CONSTITUTION: In this rotation regulating mechanism of the rotary shaft of a multi-joint robot, a fixed board 6 provided at the position separated from a driving shaft 3; a rotated body 5 connected to the driving shaft 3 through a transmission belt 4 as well as provided rotatable to the fixed board 6, and rotating at a speed lower than the rotating speed of the driving shaft 3 being transmitted by reducing the rotating speed of the driving shaft 3; and overrun detectors 7 and 8 to detect the overrun of the driving shaft 3 by detecting a projection 5a provided to the rotated body 5, and a projection 5a provided to the fixed board 6; are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation restricting mechanism for a rotary shaft of an articulated robot, and more particularly, to a rotary shaft of a joint or the like of an arm of a multi-joint robot rotating 360 ° or more (one rotation or more). The present invention relates to a rotation restricting mechanism for a rotary shaft of a multi-joint robot that allows the rotary shaft to rotate within a predetermined range while allowing the rotary shaft to overrun.

[0002]

2. Description of the Related Art Recently, industrial robots such as articulated robots have been widely introduced in mass production processes and are required to assume an arbitrary posture over a wide range. It is necessary to make the rotation angle of the axis one rotation or more (360 ° or more), but the rotation axis of more than one rotation prevents the robot itself or surrounding obstacles from interfering with the rotation movement of the rotation axis. It is also necessary to regulate the range.

As a conventional rotation restricting mechanism of this type, for example, there is one described in Japanese Utility Model Laid-Open No. 2-100792. This is the rotating base of an articulated robot.
A flange is formed around the (rotary shaft), an arc groove centered on the rotation axis is formed in the flange, the mover is loosely fitted in the arc groove, and the protrusion of the mover is loosely fitted on the flange. Then, a stop plate having a stop arc groove for restricting a rotation range is attached, and further, an engaging member that engages with the moving element is fixed to an arm that rotates about a rotation base.

In this structure, when the engaging member engages with the protrusion of the mover as the arm rotates, the mover moves along the stopper arc groove, and the mover moves to the end of the stopper arc groove. When the limit switch detects the protrusion and the protrusion contacts the rotation shaft, the rotation of the rotary shaft is stopped and a mechanical stopper is applied. By adjusting the stroke of the stopper arc groove, one or more rotations are made. The rotation range of can be regulated.

[0005]

However, in such a conventional rotation restricting mechanism, the structure of the rotation restricting mechanism is complicated because the flange, the stopper plate, the slider and the like are provided around the rotation base. In addition, there is a problem that it takes a lot of time to change or adjust the rotation range of the rotation base.

Further, since the flange and the stopper plate are provided around the rotary base, there is a problem that the diameter around the axis of the rotary base becomes large. Further, since the stroke of the stopper arc groove is adjusted to regulate the rotation range of the rotation base of one rotation or more, the regulation range of the rotation base is up to two rotations, which is a problem that the rotation regulation range is restricted. There was (there is 360 ° to 700 ° in the conventional example).

In addition, in the conventional articulated robot, when the amount of rotation of the rotating shaft (the amount of movement of the arm) is counted by the incremental encoder, the moving amount of the rotating base is always centered on the origin position, and An origin position detector must be provided as it must be returned to position. However, when the origin position detector is provided in the conventional articulated robot having the rotation restricting mechanism, the configuration around the rotation base is complicated, and thus the mounting position is limited.

In view of this, the invention according to claim 1 is a multi-joint structure capable of performing one or more rotations with a simple structure and restricting the rotation of the rotating shaft within a predetermined range of one or more rotations. It is an object of the present invention to provide a rotation restricting mechanism for a rotation axis of a robot. According to the invention of claim 2, a wide space around the rotary shaft can be secured, and the degree of freedom of the mounting positions of the detected part and the overrun detector can be greatly improved. The object of the present invention is to provide a rotation restricting mechanism for the rotating shaft of the.

According to a third aspect of the present invention, there is provided a multi-joint robot capable of decelerating a rotating body and changing a rotation range with a simple structure and restricting the rotation range of two or more rotations. It is intended to provide a rotation restricting mechanism for a rotating shaft. According to the invention described in claim 4, the origin position detector is directly provided not on the rotating shaft but on the rotated body, so that the resolution can be increased, the more accurate detection of the origin position can be performed, and the rotated position can be detected. An object of the present invention is to provide a rotation restricting mechanism for a rotary shaft of an articulated robot that can share a detected part of a body for overrun detection and origin position detection.

According to the invention of claim 5, the time required for the rotary shaft to return to the origin position can be greatly shortened, and the rotation amount of the rotary shaft can be controlled by using an inexpensive incremental encoder. It is an object of the present invention to provide a rotation restricting mechanism for a rotating shaft of an articulated robot that can be used. According to a sixth aspect of the present invention, there is provided a rotary shaft of a multi-joint robot which can easily change and adjust the rotation restriction range of the rotary shaft and can easily set the rotation of the rotary shaft to two rotations or more. It is intended to provide a rotation control mechanism.

According to a seventh aspect of the present invention, even if one of the overrun detectors fails during the runaway of the rotary shaft, the rotary shaft can be surely stopped, and a highly safe articulated robot is provided. It is intended to provide a rotation restricting mechanism for a rotating shaft. According to the eighth and ninth aspects of the invention, the detection belt is provided on the transmission belt that connects the rotation shaft and the drive shaft, and the rotation range of the rotation shaft at 360 ° or more can be restricted with a simple configuration. At the same time, it is an object of the present invention to provide a rotation restricting mechanism for a rotary shaft of an articulated robot that can reduce the number of parts of the restricting mechanism.

According to the tenth aspect of the present invention, the origin position detector is directly provided not on the rotating shaft but on the rotating body, so that the resolution can be increased and the origin position can be detected more accurately. An object of the present invention is to provide a rotation restricting mechanism for a rotating shaft of an articulated robot that can share a detected portion of a rotated body for overrun detection and origin position detection.

According to the eleventh and twelfth aspects of the present invention, the rotation range of the rotary shaft at 360 ° or more can be restricted with a simple structure, and even when the overrun detectors can be arranged in only one row. It is an object of the present invention to provide a rotation restricting mechanism for a rotating shaft of an articulated robot that can sufficiently deal with the problem.

[0014]

According to the first aspect of the present invention,
In order to solve the above problems, in a rotation restricting mechanism of a rotating shaft that restricts rotation of a rotating shaft that constitutes a joint part of an articulated robot within a predetermined range, a fixed base provided at a position separated from the rotating shaft, It is rotatably provided on the fixed base and is connected to a rotary shaft via a rotational force transmitting means, and the rotational speed of the rotary shaft is decelerated and transmitted to thereby rotate at a lower speed than the rotational speed of the rotary shaft. A rotating body; a detected portion provided on the rotated body; and an overrun detector that is provided on the fixed base and detects an overrun of the rotating shaft by detecting the detected portion. It is characterized by that.

According to a second aspect of the present invention, in order to solve the above-mentioned problems, in the first aspect of the present invention, the rotational force transmitting means comprises a rotating shaft and a transmission belt wound around a rotating body, The rotational force of the rotating shaft is transmitted to the rotated body via the transmission belt. Claim 3
In order to solve the above-mentioned problems, in the invention described in claim 1 or 2, the radius of the rotated body is n (where n is 1 or more) times the radius of the rotating shaft. It is a feature.

In order to solve the above-mentioned problems, the invention according to claim 4 is the invention according to any one of claims 1 to 3,
The fixed base is provided with an origin position detector that detects the detected position as the origin position of the rotation axis when the detected portion is detected, and the overrun detector is rotated with the origin position detector interposed therebetween. It is characterized in that it is provided in both directions of rotation of the body.

In order to solve the above-mentioned problems, a fifth aspect of the present invention is, in the invention of the fourth aspect, provided with a fan-shaped detected portion provided on the rotating body, and a fixed base. A direction detector for detecting the detection unit, wherein the fan-shaped detected unit is one side or the other side of the rotating body with respect to the origin position detector, the detected unit being detected by the overrun detector. It is provided at a predetermined position of the rotated body so as to be detected by the direction detector when it is in any one of the rotation directions.

In order to solve the above problems, the invention according to claim 6 is the invention according to claim 4 or 5, wherein the mounting positions of the overrun detector and the origin position detector are on a fixed base. It is characterized by being variable. According to a seventh aspect of the invention, in order to solve the above-mentioned problems, in the invention according to any one of the first to sixth aspects, a second portion is provided in a rotated body portion on a downstream side in the rotation direction with respect to the detected portion.
Is to be detected.

In order to solve the above-mentioned problems, the present invention provides a rotation restricting mechanism for a rotary shaft which restricts rotation of a rotary shaft constituting a joint part of an articulated robot within a predetermined range. Is a driven shaft connected to a drive shaft via a transmission belt, and the drive shaft is separated from the driven shaft so as to be located at an inter-axis distance longer than the peripheral length of the driven shaft, and the drive belt has a predetermined length. It is characterized in that a detected portion is provided at a position and an overrun detector capable of detecting the detected portion is provided between the drive shaft and the driven shaft.

According to a ninth aspect of the invention, in order to solve the above-mentioned problems, in a rotation regulating mechanism of a rotation shaft for regulating rotation of a rotation shaft constituting a joint part of an articulated robot within a predetermined range, the rotation shaft is provided. Is composed of a driven shaft connected to a drive shaft via a transmission belt, and teeth having a predetermined pitch are formed on the inner peripheral surface of the transmission belt, and a pitch larger than the pitch of the inner peripheral surface is formed on the outer peripheral surface thereof. A fixed base on the outer peripheral surface of the transmission belt, a rotatable body rotatably mounted on the fixed base and meshing with the teeth of the transmission belt, and a detected portion provided on the rotated body. And an overrun detector that is provided on the fixed base and that detects overrun of the rotation axis by detecting the detected portion.

According to a tenth aspect of the invention, in order to solve the above-mentioned problems, in the invention according to the ninth aspect, the detection position is detected by the fixed base when the detected portion is detected. An origin position detector is installed to detect
The overrun detector is provided in both directions of rotation of the rotated body with the origin position detector interposed therebetween.

In order to solve the above-mentioned problems, the present invention provides a rotation shaft rotation restricting mechanism for restricting rotation of a rotation shaft constituting a joint part of an articulated robot within a predetermined range. One end of which is fixed to the wire, and the wire which can be wound around and unwound from the rotary shaft as the rotary shaft rotates,
An urging member that is provided at the other end of the wire and urges the wire linearly, a detected portion that is provided at a predetermined position of the wire, and an overrun of the rotating shaft by detecting the detected portion. And an overrun detector for detecting.

According to a twelfth aspect of the present invention, in order to solve the above-mentioned problems, a rotation which constitutes a joint portion of an articulated robot and regulates rotation of a rotary shaft rotatably attached to a fixed base within a predetermined range. In the rotation regulation mechanism of the shaft, one end is fixed to the rotating shaft and the other end is fixed to a fixed base,
A first wire that can be wound around and unwound from the rotary shaft as the rotary shaft rotates, a pulley provided on the wire, and one end attached to the pulley and the other end attached to the biasing member. And a second wire that is linearly urged by the urging member, a detected portion provided at a predetermined position of the second wire, and the detected portion to detect an overrun of the rotating shaft. And an overrun detector that does this.

[0024]

According to the first aspect of the invention, a fixed base provided at a position separated from the rotary shaft, and a fixed base rotatably mounted on the fixed base and connected to the rotary shaft via a rotational force transmitting means, The rotational speed of the rotating shaft is reduced and transmitted to rotate the rotating body at a speed lower than the rotating speed of the rotating shaft, the detected portion provided on the rotating body, and the fixed base. And an overrun detector that detects the overrun of the rotation axis by detecting the section.

Therefore, since the overrun detector and the object to be detected are provided on the rotating body which is separated from the drive shaft that directly drives the joint such as the wrist of the articulated robot, the structure around the drive shaft becomes complicated. Never be. Further, since the rotation of the rotating shaft is decelerated and transmitted to the rotated body, the rotating body can regulate the rotation of the rotating shaft with a smaller amount of rotation than the rotation of the rotating shaft. Therefore, if an overrun detector is provided at an arbitrary position on the fixed base, the rotation range of the rotary shaft can be easily regulated at 360 ° or more (one rotation or more).

According to the second aspect of the present invention, the rotational force transmitting means comprises a rotating shaft and a transmission belt wound around the rotating body, and the rotating force of the rotating shaft is transmitted to the rotating body via the transmitting belt. It Therefore, the rotating shaft is reliably separated from the rotating body, and even if the rotating shaft is separated, the rotational force of the rotating shaft is transmitted to the rotating body through the belt, so that a wide space around the rotating shaft is secured. The degree of freedom in the mounting positions of the detected part and the overrun detector is significantly improved.

According to the third aspect of the invention, the radius of the rotating body is n times (where n is 1 or more) times the radius of the rotating shaft. Therefore, for example, when the radius of the rotated body is twice the radius of the rotating shaft, the reduction ratio becomes 1: 2, and the rotating body rotates 1/2 while the rotating shaft makes one rotation. By mounting the overrun detector at any position on the table, it is possible to easily regulate the rotation shaft at 360 ° or more. Further, if the radius difference between the rotating shaft and the rotated body is further increased and the reduction ratio is further increased, the range can be restricted when the rotating shaft rotates two times or more.

According to the fourth aspect of the present invention, the fixed base is provided with an origin position detector for detecting the detected position as the origin position of the rotary shaft when the detected portion is detected, and the overrun detector is the origin. It is provided in both directions of the rotating body with the position detector interposed therebetween. Therefore, since the origin position detector is provided directly on the rotating body, not on the rotating shaft, the resolution becomes larger than that when it is provided on the rotating shaft, and more accurate detection of the origin position is performed. Specifically, when the radius of the rotated body is twice as large as the radius of the rotating shaft, the resolution twice as high as that obtained by providing the origin position detector on the rotating shaft can be obtained. Further, since the detected part of the rotating body is shared for overrun detection and origin position detection, the structure of the rotation restricting mechanism does not become complicated and the cost of the rotation restricting mechanism does not increase.

According to a fifth aspect of the present invention, there is provided a fan-shaped detected part provided on the rotating body and a direction detector provided on the fixed base for detecting the detected part. The detection unit is detected by the direction detector when the detected unit detected by the overrun detector is in the rotation direction of one side or the other side of the rotated body with respect to the origin position detector. Is provided at a predetermined position of the rotated body.

Therefore, for example, when the detected part moves to one side from the origin position detector when the rotated part rotates, when the fan-shaped detected part is detected by the direction detector, the detected part is detected. Is detected on one side, the rotation axis is rotated from this state toward the origin position, and when the detected part moves from the origin position detector to the other side, When the detected part of is not detected by the direction detector, it is detected that the detected device is located on the other side, so by rotating the rotation axis toward the origin position from this state, The time required for the rotary shaft to return to the origin position can be significantly shortened, and the rotary range of the rotary shaft (rotary range of the robot arm) can be minimized.

Further, even when the amount of rotation of the rotary shaft is counted by the incremental encoder, the return to the origin position can be easily performed, so that ordinary robot control can be performed at low cost. On the other hand, if an absolute encoder is used, it is possible to easily return to the origin position, but it is very expensive and not preferable for use.

According to the sixth aspect of the invention, since the mounting positions of the overrun detector and the origin position detector can be varied on the fixed base, the rotation restriction range of the rotary shaft can be easily changed and adjusted. In addition, the mounting position of the overrun detector can be arbitrarily set, so that the rotary shaft can be easily rotated more than two times. In the invention according to claim 7, since the second detected portion is provided in the rotated body portion on the downstream side in the rotation direction with respect to the detected portion, one of the overrun detectors fails and the overrun detector is damaged. When the rotating shaft runs away without detecting the rotating body, the second detected portion provided on the downstream side of the rotating shaft is detected by another normal overrun detector. Therefore, 1
Even if one of the overrun detectors fails, the rotating shaft can be reliably stopped and safety is greatly improved.

In the invention according to claim 8, the rotary shaft is composed of a driven shaft connected to the drive shaft via a transmission belt, and the drive shaft is positioned at an axial distance longer than the circumferential length of the driven shaft. Thus, the detected portion is provided at a predetermined position of the transmission belt, and an overrun detector capable of detecting the detected portion is provided between the drive shaft and the driven shaft.

Therefore, since the detected device is provided on the transmission belt connecting the driven shaft and the driving shaft, the moving distance of the detected portion of the transmission belt is changed by varying the distance between the driven shaft and the driving shaft. By making the rotation range of the shaft variable, the rotation range of the driven shaft (rotation shaft) at 360 ° or more can be regulated with a simple structure. As a result, the number of parts of the regulation mechanism is reduced, and the cost of the rotation regulation mechanism is reduced.

According to a ninth aspect of the present invention, the rotary shaft comprises a driven shaft connected to the drive shaft via a transmission belt,
Teeth having a predetermined pitch are formed on the inner peripheral surface of the transmission belt, and teeth having a pitch larger than the pitch of the inner peripheral surface are formed on the outer peripheral surface thereof. A fixed base is provided on the outer peripheral surface of the transmission belt, a rotatable body that is rotatably provided on the fixed base and meshes with the teeth of the transmission belt, a detected portion provided on the rotated body, and the fixed body. An overrun detector, which is provided on the table and detects the detected portion to detect an overrun of the rotating shaft, is provided.

Therefore, since the pitch of the teeth of the transmission belt meshing with the driven body is larger than the pitch of the teeth of the transmission belt meshing with the drive shaft, the rotation of the driven shaft is decelerated and transmitted to the driven body. Rotation of the shaft over 360 ° is easily allowed, and the range of rotation can be regulated.
Further, since the rotation range of the driven shaft is regulated by using the transmission belt, the number of parts of the rotation regulation mechanism is reduced and an inexpensive rotation regulation mechanism can be obtained.

According to the tenth aspect of the invention, the fixed base is provided with an origin position detector that detects the detected position as the origin position of the rotary shaft when the detected portion is detected, and the overrun detector is the origin. It is provided in both directions of the rotating body with the position detector interposed therebetween. Therefore, since the origin position detector is provided directly on the rotating body, not on the rotating shaft, the resolution becomes larger than that when it is provided on the rotating shaft, and more accurate detection of the origin position is performed. Specifically, when the radius of the rotated body is twice as large as the radius of the rotating shaft, the resolution twice as high as that obtained by providing the origin position detector on the rotating shaft can be obtained. Further, since the detected part of the rotating body is shared for overrun detection and origin position detection, the structure of the rotation restricting mechanism does not become complicated and the cost of the mechanism does not increase.

According to the eleventh aspect of the present invention, one end of the wire is fixed to the rotary shaft, and the wire can be wound around and unwound from the rotary shaft as the rotary shaft rotates, and the wire is provided at the other end of the wire. An urging member that linearly urges the wire, a detected portion provided at a predetermined position of the wire, an overrun detector that detects the detected portion and detects an overrun of the rotating shaft, Is provided.

Therefore, the rotation range of the rotary shaft at 360 ° or more can be restricted by the overrun detector detecting the object to be detected which moves linearly with the rotation of the rotary shaft. The structure of can be simplified.
Further, since the detected object can be linearly moved by the wire, it is possible to sufficiently cope with the case where the overrun detectors can be arranged in only one row.

According to the twelfth aspect of the present invention, one end is fixed to the rotary shaft and the other end is fixed to the fixed base, and the rotary shaft can be wound and unwound with respect to the rotary shaft. A first wire, a pulley provided on the wire, a second wire having one end attached to the pulley and the other end attached to a biasing member, and linearly biased by the biasing member, A detected portion provided at a predetermined position of the second wire and an overrun detector that detects the detected portion and detects an overrun of the rotating shaft are provided.

Therefore, the rotation range of the rotary shaft above 360 ° can be regulated by the overrun detector detecting the object to be detected which moves linearly with the rotation of the rotary shaft. The structure of can be simplified.
Further, since the detected object can be linearly moved by the wire, it is possible to sufficiently cope with the case where the overrun detectors can be arranged in only one row. Further, since the pulley is provided on the first wire wound around the rotary shaft and the one end of the second wire is provided on the first wire, the detected portion moves linearly in one direction or the other direction. The movement distance when doing can be halved compared to the one without a pulley, and the installation space for the rotation restricting mechanism can be reduced.

[0042]

EXAMPLES The present invention will be described below based on examples.
1 and 2 are views showing an embodiment of a rotation restricting mechanism of a rotary shaft of an articulated robot according to the invention described in any one of claims 1 to 4. First, the configuration will be described. 1 and 2, a rotary shaft 1 that constitutes a joint such as a wrist or an elbow to which an arm of an articulated robot is connected is connected to a drive shaft 3 that is rotationally driven by a drive motor and a speed reducer via a transmission belt. The rotary shaft 1 is connected to the drive shaft 3 via the transmission belt 2.
Is driven to rotate. Further, the drive shaft 3 is provided with a drive pulley 3a, the pulley 3a and the rotary shaft 1 have the same radius, and the rotation of the drive shaft 3 is transmitted to the rotary shaft 1 without deceleration. In this example,
The rotary shaft 1, the drive shaft 3, and the drive pulley 3a constitute a joint of an articulated robot.

On the other hand, a transmission belt 4 as a rotational force transmission means is wound around the drive shaft 3, and the transmission belt 4
Is connected to the rotated body 5. This rotated body 5 is rotatably attached to a fixed base 6, and the rotation of the drive shaft 3 is transmitted to the rotated body 5 via a transmission belt 4. Also,
The radius of the rotated body 5 is set to be twice the radius of the drive shaft 3, and the rotation of the drive shaft 3 is decelerated and transmitted to the rotated body 5 via the transmission belt 4, and the rotated body 5 is driven. It rotates at a low speed with respect to the shaft 3. In the present embodiment, the driven shaft 5 rotates once while the driven body 5 rotates 1/2, and the reduction ratio is 2: 1.

Further, the rotating body 5 is formed with a projection 5a as a detected body, and the projection 5a is detected by the overrun detectors 7 and 8 and the origin position detector 9. . The overrun detectors 7 and 8 are composed of proximity sensors, and are arranged 180 ° apart from each other on the fixed base 6. When the protrusions 5a come close to each other, they are detected and a detection signal is sent to a controller (not shown). It is designed to output. When this detection information is input, the controller stops driving the drive shaft 3 and stops the rotary shaft 1.

In this embodiment, the rotary shaft 1 and the rotating body 5 are
Is set to 2: 1 and the overrun detector 7,
Since 8 are separated by 180 °, the rotated body 5 is allowed to rotate within the range of 180 °, and the drive shaft 3 is allowed to rotate once, that is, within the range of 360 °. The overrun detectors 7 and 8 are, of course, disposed at appropriate positions so as to avoid interference with the robot itself or surrounding obstacles.

Further, the origin position detector 9 is attached to the fixed base 6 at a position separated by 90 ° from the overrun detectors 7 and 8, and the overrun detectors 7 and 8 detect the origin position. It is provided in both directions (+ direction and − direction) of the rotating body 5 with the container 9 interposed therebetween. The detector 9 sets the origin position of the rotary shaft 1 and is composed of a proximity sensor, which detects the proximity of the protrusion 5a and outputs a signal to the controller. The controller controls the rotary shaft 1 by grasping the rotation speed and the current position of the rotary shaft 1 based on the detection information of the origin position detector 9 and the detection information from the encoder provided on the rotary shaft 1. There is.

The overrun detectors 7 and 8 and the origin position detector 9 are attached to the main bodies 100, 101 and 102, respectively, and the slits 100a, 101a and 102a formed in the main bodies 100, 101 and 102 are The position on the fixed base 6 can be changed by sliding on the bolts 100b, 101b, 102b screwed onto the fixed base 6. Then, after the mounting position is changed, the bolts 100b, 101b, 102b are fastened to the main bodies 100, 101, 102 so as to be fixed at arbitrary positions on the fixing base 6.

Next, the operation will be described. In this embodiment, when the robot is stationary, the rotary shaft 1 is stopped at a position where the protrusion 5a is close to the origin position detector 9. When the drive shaft 3 is driven to rotate the wrist or elbow of the robot when the robot is driven, this drive force is transmitted to the rotary shaft 1 via the transmission belt 2, and the rotary shaft 1 is driven by the drive shaft. Rotate the same amount as 3. At this time, the rotational force is transmitted from the drive shaft 3 to the rotated body 5 via the transmission belt 4, so that the rotated body 5 rotates 1/2 rotation with respect to the drive shaft 3.

At this time, the rotated body 5 is the origin position detector 9
On the other hand, when the protrusion 5a is rotated by either the overrun detector 7 side or the overrun detector 8 side and the protrusion 5a is detected by the overrun detector 7 or the overrun detector 8, the detector 7 or 8 Since the signal is output from either one to the controller, the drive of the drive shaft 3 is stopped by the controller. At this time, since the rotating body 5 rotates by 1/2 rotation with respect to the rotation speed of the drive shaft 3, if the detectors 7 and 8 are arranged 180 degrees apart, the rotation shaft 1 will rotate sufficiently once. The rotation range can be restricted to one rotation as well as the rotation.

As described above, in this embodiment, the fixed base 6 is provided at a position separated from the drive shaft 3, and the fixed base 6 is rotatably mounted on the fixed base 6 and is connected to the drive shaft 3 via the transmission belt 4. , The rotational speed of the drive shaft 3 is reduced and transmitted, and the rotated body 5 rotates at a speed lower than the rotational speed of the drive shaft, and the protrusion 5a provided on the rotated body 5.
And overrun detectors 7 and 8 provided on the fixed base 6 for detecting the protrusion 5a and detecting the overrun of the rotated body 5.
Since the above is provided, the overrun detectors 7 and 8 and the detected object 5 can be provided on the rotated body 5 that is separated from the drive shaft 3 that directly drives the joint such as the wrist of the robot. It is possible to prevent the structure around 3 and the rotary shaft 1 from becoming complicated.

Since the rotation of the drive shaft 3 is decelerated and transmitted to the rotated body 5, the rotated body 5 rotates the drive shaft 3 with a smaller rotation amount than the rotation of the drive shaft 3. Can be regulated. Therefore, if the overrun detectors 7 and 8 are provided at arbitrary positions on the fixed base 6, for example, at positions 180 ° or more with the origin position detector 9 interposed therebetween, 360 ° or more (1
It is possible to easily regulate the rotation range of the rotating shaft 1 in the rotation or more).

Further, since the transmission belt 4 is wound between the drive shaft 3 and the rotated body 5 and the rotational force of the drive shaft 3 is transmitted to the rotated body 5 via the transmission belt 4, the drive shaft 3 Can be reliably separated from the rotated body 5, and even if it is separated, the rotational force of the drive shaft 3 can be transmitted to the rotated body 5 via the belt 4, and the space around the drive shaft 3 can be saved. It can be secured widely. Therefore, the degree of freedom of the mounting positions of the protrusion 5a and the overrun detectors 7 and 8 can be significantly improved.

Since the radius of the rotated body 5 is twice the radius of the drive shaft 3, the reduction ratio is set to 2: 1 and the drive shaft 3 is set.
It is possible to rotate the rotated body 5 by 1/2 during one rotation of. Therefore, if the overrun detectors 7 and 8 are attached to arbitrary positions of the fixed base 6, it is possible to easily regulate the drive shaft 3 at a rotation of 360 ° or more. Further, by further increasing the radius difference between the drive shaft 3 and the rotated body 5 and further increasing the reduction ratio, it is possible to restrict the range in which the drive shaft 1 rotates two or more times.

Further, the fixed base 6 is provided with an origin position detector 9 for detecting the detected position as the origin position of the drive shaft 3 when the protrusion 5a is detected, and the overrun detectors 7 and 8 are used as the origin position detectors. Since it is provided on both sides of the rotating body 5 with the origin 9 interposed therebetween, the resolution can be increased compared to the case where the origin position detector 9 is provided on the rotary shaft 1 or the drive shaft 3 in a straight line. It is possible to detect various origin positions.

Specifically, the radius of the rotated body 5 is the drive shaft 3
If the radius is twice as large as the radius, the resolution twice as high as that of the rotary shaft 1 or the drive shaft 3 provided with the origin position detector 9 can be obtained. In addition, the protrusion 5 of the rotating body 5
Since a can be shared for overrun detection and origin position detection, it is possible to prevent the structure of the rotation restriction mechanism from becoming complicated and prevent the cost of the mechanism from increasing.

Further, since the mounting positions of the overrun detectors 7 and 8 and the origin position detector 9 can be varied on the fixed base 6, the rotation restriction range of the rotary shaft 1 can be easily changed and adjusted. By setting the mounting positions of the overrun detectors 7 and 8 arbitrarily, the rotary shaft 1
Can be easily rotated more than two times. In the present embodiment, the drive shaft 3 and the rotary shaft 1 constitute a joint of a multi-joint robot, and the rotary shaft 1 is separated from the drive shaft 3. However, the rotary shaft 1 is a linear drive motor and deceleration. It may be driven by a machine. Further, the rotating body 5 is provided with the protrusion 5a as the rotated body, but the present invention is not limited to this, and a non-projecting one such as a slit or a hole is provided, and when the slit or the hole is close to the overrun detection, It is also possible to provide an optical sensor that optically detects this slit or the like. Further, the overrun detector may be provided with a touch sensor that comes into contact with the protrusion 5a.

In addition to the overrun detector, for example, a stopper that abuts the protrusion 5a may be provided.
When the rotation of the rotated body 5 is mechanically stopped by the stopper, the motor and the speed reducer may be damaged.
It is preferable to provide a non-contact type detection mechanism or a soft touch detection mechanism as in this embodiment in order to protect the motor and the speed reducer.

FIG. 3 is a diagram showing an embodiment of a rotation restricting mechanism for a rotary shaft of an articulated robot according to the invention of claim 5. The present embodiment is different from the above-mentioned embodiment in that a fan-shaped detected portion is provided on the detected object and the direction detector is provided on the fixed base, and the other configurations are the same. The same configurations are denoted by the same reference numerals and the description thereof will be omitted. In this embodiment, as shown in FIG. 3A, a fan-shaped projection 11 is provided as an object to be detected on the outer peripheral portion of the object to be detected 5, and when the projection 11 approaches the fixed base 6, The direction detector 12 including a proximity sensor for detecting
The protrusion 11 is a direction detector when the protrusions 7 and 8 are in the rotation direction of the overrun detector 7 side with respect to the origin position detector 9.
It is provided at a predetermined position of the rotated body 5 so as to be detected by 12. The protrusion 11 is not on the detector 7 side, but on the detector 8
It may be provided on the rotated body 5 so as to be detected by the direction detector 12 when it is on the side.

Since the present embodiment is constructed as described above, when the detected part 5 moves from the origin position detector 9 to the detector 7 side when the rotated body 5 rotates, the same figure ( As shown in a), when the fan-shaped protrusion 11 is detected by the direction detector 12, it is detected that the protrusion 5a is located on the detector 7 side. When the protrusion 5a is moved from the origin position detector 9 to the detector 8 side, the protrusion 11 is detected by the direction detector 12 as shown in FIG. If not, the protrusion 5a is detected to be located on the detector side.
By immediately rotating the rotary shaft 1 toward the home position detector 9, the time required for the rotary shaft 1 to return to the home position can be significantly shortened and the rotation range of the rotary shaft 1 (rotation of the robot arm Range) can be minimized.

Further, even when the amount of rotation of the rotary shaft 1 is counted by the incremental encoder, the return to the origin position can be easily performed, so that ordinary robot control can be performed at low cost. On the other hand, if you use an absolute encoder, you can easily return to the home position (as is well known, since the number of pulses from the home position is always counted, the home position detector is not required. Therefore, it is not preferable for use because it is very expensive. In the present embodiment, the fan-shaped protrusion is provided as the detected object, but the present invention is not limited to this, and a fan-shaped slit may be provided and an optical sensor for optically detecting this slit may be provided as the overrun detector. good. Also,
The positions of the protrusion 11 and the direction detector 12 are not limited to the positions shown in the figure, and may be any positions on the concentric circle of the rotated body 5. Further, the types of the detectors 7, 8 and 12 may be changed so that the overrun detectors 7 and 8 and the direction detector 12 do not interfere with each other.

FIG. 4 is a diagram showing an embodiment of a rotation restricting mechanism for a rotary shaft of an articulated robot according to the invention of claim 7. The present embodiment is different from the one embodiment of the invention described in any one of claims 1 to 4 and 6 in that a second detector different from the protrusion 5a is provided on the rotated body 5. Since the configurations are the same, the same numbers are given to the same configurations as those in the above-mentioned embodiment, and the description will be omitted.

In FIG. 4 (a), the rotated body 5 is provided with projections 14 and 15 as second detected parts, and these projections 14 and 15 of the rotated body 5 with respect to the projection 5a. It is provided on the downstream side in the rotation direction. Further, in the present embodiment, the rotated body 5
The radius is set to be three times that of the drive shaft 3, and the reduction ratio is set to 1: 3. Next, the operation will be described.

If the detector 7 fails for some reason, the rotary shaft 3 rotates and the protrusion 5a of the rotated body 5 faces the detector 7 as shown in FIG. Move, same figure
As shown in (b), even if the protrusion 5 a approaches the detector 7, the detection is not performed and the protrusion 5 a passes by the detector 7. In this embodiment, the protrusion 14 is provided on the downstream side of the protrusion 5a in the rotation direction of the rotated body 5, so that the protrusion 14a
Is close to the normal detector 8, this detector 8 will make this protrusion.
Since 14 is detected and a signal is output to the controller, the controller can prevent the drive shaft 3 from being driven to prevent the rotation shaft 1 from running away and the arm from interfering with obstacles and the like around it.

Further, even if the rotating body 5 rotates toward the detector 8 side when the detector 8 fails, the normal detector 7 detects the protrusion 15 so that the rotating shaft 1 runs away. Can be prevented. As described above, in the present embodiment, even if any of the overrun detectors 7 and 8 fails, the rotary shaft 1 can be reliably stopped and the safety can be greatly improved.

FIG. 5 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of an articulated robot according to the invention of claim 8. First, the configuration will be described. In FIG. 5, 21 is a driven shaft as a rotating shaft that constitutes a joint of the robot, 22 is a drive shaft driven through a drive motor and a speed reducer (not shown), and the drive shaft 22 is defined by the circumference of the driven shaft 21. Is separated from the driven shaft 21 by a long distance between the shafts, and the transmission belt 23
Are linked by.

A metal piece 24 as a detected portion is provided at a predetermined position of the transmission belt 23, and the metal piece 24 is detected by the overrun detectors 25 and 26. The overrun detectors 25 and 26 are composed of a pair of proximity sensors provided between the driven shaft 21 and the drive shaft 22, and detect the metal piece 24 and output a signal to a controller (not shown). There is. The controller stops the drive of the drive shaft 22 when this detection information is input, and prevents the arm from running away via the driven shaft 21. Further, the detectors 25 and 26 are separated from each other by at least a distance that allows the driven shaft 21 to rotate 360 ° or more. Therefore, when it is desired to increase the rotational speed of the driven shaft 21, It may be separated by a distance according to the rotation speed.

In this embodiment, when the drive shaft 22 is driven, this drive force is transmitted to the driven shaft 21 via the transmission belt 23,
The driven shaft 21 rotates. At this time, since the transmission belt 23 moves as the drive shaft 22 rotates, the metal piece 24 moves linearly. When one of the detectors 25 and 26 detects the metal piece 24, the driving of the drive shaft 22 in one direction is stopped. When the other of the metal pieces 26 or 25 is detected, the driving of the drive shaft 22 in the other direction is stopped. In this way, the rotation range of the driven shaft 21 is regulated.

In this embodiment, the metal piece 24 is thus provided on the transmission belt 23, and the moving distance of the metal piece 24 can be made variable by changing the distance between the driven shaft 21 and the drive shaft 22. Therefore, the rotation range of the driven shaft 21 (rotating shaft) at 360 ° or more can be restricted with a simple structure. As a result,
The number of parts of the rotation restricting mechanism can be reduced, and the cost of the rotation restricting mechanism can be reduced.

In this embodiment, the metal piece 24 is provided as the detected part and the proximity sensors are provided as the overrun detectors 25 and 26, but the present invention is not limited to this, and the magnet is provided as the detected part. A hall element may be provided as an overrun detector. Further, in this embodiment, a large axial distance between the driven shaft 21 and the drive shaft 22 is secured, but when this distance is short, the detectors 25 and 26 are connected to the transmission belt 23 as shown in FIG. It may be provided on both sides. By doing so, there is an effect that the installation space of the rotation restricting mechanism can be reduced.

FIG. 7 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of an articulated robot according to the invention of claim 9 or 10. First, the configuration will be described. In FIG. 7 (a), 31 is a driven shaft as a rotating shaft that constitutes a joint of the robot, 32 is a drive shaft having the same radius as the driven shaft 31 and driven through a drive motor and a speed reducer (not shown). The driven shaft 31 and the drive shaft 32 are connected by a transmission belt 33.

A fixed base 34 is provided between the driven shaft 31 and the drive shaft 32, and a rotating body 35 is mounted on the fixed base 34.
Are rotatably supported. Fig. 7 (b) shows A in Fig. 7 (a).
As shown in an enlarged view of the portion, teeth 33a having a predetermined pitch P ₁ are formed on the inner peripheral surface of the transmission belt 33, and
Its on the outer peripheral surface and the teeth 33b are formed with a large pitch P ₂ than the pitch P ₁ of the inner peripheral surface, the teeth 33a are driven shaft 3
The tooth 33b meshes with a non-detailed tooth formed on the drive shaft 32, and the tooth 33b meshes with a non-detailed tooth formed on the rotated body 35. Therefore, the rotated body 35 is decelerated with respect to the driven shaft 31 and rotates at a low speed.

A projection 35a as a detected object is formed on the rotating body 35, and the projection 35a is detected by the origin position detector 36 and the overrun detectors 37 and 38. . The overrun detectors 37 and 38 are composed of proximity sensors, and are arranged 180 ° apart from each other on the fixed base 34. When the protrusions 35a approach, they are detected and a detection signal is sent to a controller (not shown). It is designed to output. When this detection information is input, the controller stops driving the drive shaft 32 and stops the driven shaft 31.

In this embodiment, the reduction ratio of the driven shaft 31 and the rotated body 35 is set to 1: 2 by devising the pitch P ₁ and P ₂ of the teeth 33a and 33b, and the overrun detector 37, 38
Are 180 degrees apart, the rotated body 35 is allowed to rotate in the range of 180 degrees, and the driven shaft 31 is allowed to make one rotation, that is, 360 degrees. Further, the origin position detector 36 is attached to the fixed base 34 at a position separated by 90 ° with respect to the overrun detectors 37 and 38,
The overrun detectors 37, 38 are provided in both directions (+ direction and − direction) of the rotating direction of the rotated body 35 with the origin position detector 36 interposed therebetween. This detector 36 is also composed of a proximity sensor, and when the protrusion 35a approaches, it is detected and a signal is output to the controller. The controller controls the driven shaft 31 by grasping the rotation speed and the current position of the driven shaft 31 based on the detection information of the origin position detector 36 and the detection information from the encoder provided on the driven shaft 31. There is.

In this embodiment having such a configuration, the pitch of the teeth 33b of the transmission belt 33 meshing with the driven body 35 is larger than the pitch of the teeth 33a of the transmission belt 33 meshing with the drive shaft 31. As a result, the rotation of the driven shaft 31
It is possible to reduce the speed of transmission to 35 and transmit it, and it is possible to easily allow the driven shaft 31 to rotate by 360 ° or more, and at the same time, to regulate the rotation range. Moreover, since the rotation range of the driven shaft 31 can be regulated by using the transmission belt 33, the number of parts of the rotation regulation mechanism can be reduced and an inexpensive rotation regulation mechanism can be obtained.

Further, since the origin position detector 36 is provided on the fixed base 34, the resolution can be made larger than in the case where it is provided on the driven shaft 31 and the drive shaft 32, and the origin position can be detected more accurately. be able to. In addition, the protrusion 35a of the rotating body 35
Since it can be used for both overrun detection and origin position detection, it is possible to prevent the structure of the rotation restricting mechanism from becoming complicated, and it is possible to prevent the cost of the mechanism from increasing.

FIG. 8 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of an articulated robot according to the invention of claim 11. First, the configuration will be described. Reference numeral 41 denotes a rotary shaft that constitutes a joint of the robot, and the rotary shaft 41 is driven by a motor and a speed reducer. One end of a wire 42 is fixed to the rotary shaft 41, and the wire 42 is wound around and unwound from the rotary shaft 41 as the rotary shaft 41 rotates. A tension spring 43 as a biasing member is provided at the other end of the wire 42, and the wire 42 is linearly biased by the tension spring 43.

A metal piece 44 as a detected portion is provided at a predetermined position of the wire 42, and the metal piece 44 is detected by the overrun detectors 45 and 46. The detectors 45, 46 are composed of proximity sensors, are arranged along the wire 42, and output detection information to a controller (not shown) when the metal piece 44 is detected. When the controller inputs this detection information,
The drive of the rotary shaft 41 is stopped.

In this embodiment, when the rotating shaft 41 rotates in one direction, the wire 42 is wound around the rotating shaft 41 and
When the wire 41 rotates in the other direction, the wire 42 is unwound. The metal piece 44 moves linearly in the horizontal direction in FIG. 8 as the wire 42 is wound and unwound.
When either one of 45 and 46 is detected, the controller detects the rotation axis based on the detection information from one of the detectors 45 and 46.
Stop driving 41. Therefore, depending on the radius of the rotary shaft 41 and the distance between the overrun detectors 45 and 46,
The rotation of 41 over 360 ° and its rotation range can be easily allowed.

As described above, in this embodiment, the detectors 45 and 46 detect the metal piece 44 that moves linearly with the rotation of the rotary shaft 41, thereby restricting the rotation range of the rotary shaft at 360 ° or more. Therefore, the structure of the rotation restricting mechanism can be simplified. Further, since the metal piece 44 can be linearly moved by the wire 42, it is possible to sufficiently cope with the case where the detectors 45 and 46 can be arranged in only one row.

In this embodiment, the metal piece 44 is provided as the detected part and the proximity sensors are provided as the overrun detectors 45 and 46. However, the present invention is not limited to this, and the magnet is provided as the detected part. A hall element may be provided as an overrun detector. FIG. 9 is a diagram showing an embodiment of a rotation restricting mechanism for a rotating shaft of an articulated robot according to the invention of claim 12.

First, the structure will be described. Reference numeral 51 is a rotary shaft that constitutes a joint of the robot, and the rotary shaft 51 is rotatably fixed to a fixed base 52 and driven by a motor and a speed reducer. One end of a wire 53 as the first wire, the other end of which is fixed to the fixed base 52, is fixed to the rotary shaft 51, and the wire 53 is fixed to the rotary shaft 51 as the rotary shaft 51 rotates. It is designed to be wound and unwound. The wire 53 is provided with a pulley 54, and one end of a wire 55 as a second wire is attached to the pulley 54.

A tension spring 56 as a biasing member is provided at the other end of the wire 55, and the wire 55 is linearly biased by the tension spring 56. In addition, a metal piece 57 as a detected portion is provided at a predetermined portion of the wire 55.
This metal piece 57 is an overrun detector.
It is detected by 58 and 59. The detectors 58 and 59 are composed of proximity sensors, are arranged along the wire 55, and output detection information to a controller (not shown) when the metal piece 57 is detected. When the detection information is input, the controller stops driving the rotating shaft 51.

In this embodiment, when the rotary shaft 51 rotates in one direction, the wire 53 is wound around the rotary shaft 51 and
When the 51 rotates in the other direction, the wire 53 is unwound. Since the pulley 54 linearly moves the wire 55 in the left-right direction in FIG. 9 as the wire 53 is wound and unwound, the metal piece 57 attached to the wire 55 is detected by one of the detectors 58 and 59. When one of them is detected, the controller stops driving the rotating shaft 51 based on the detection information from either of the detectors 58 and 59. Therefore, it is possible to easily allow the rotation of the rotation shaft 51 to be 360 ° or more and its rotation range depending on the radius of the rotation shaft 51 and the distance between the overrun detectors 58 and 59.

As described above, in the present embodiment, the detectors 58 and 59 detect the metal piece 57 that moves linearly with the rotation of the rotary shaft 51, so that the rotary range of the rotary shaft 51 at 360 ° or more is determined. It is possible to regulate, and the structure of the rotation regulating mechanism can be simplified. Further, since the metal piece 57 can be linearly moved by the wires 53 and 55, it is possible to sufficiently cope with the case where the detectors 58 and 59 can be arranged only in one row.

Further, the wire 53 wound around the rotary shaft 51.
Since the pulley 54 and the wire 55 are provided on the pulley 54, the moving distance when the metal piece 57 moves linearly in one direction or the other direction can be halved as compared with the case without the pulley. The installation space for the rotation regulation mechanism can be reduced. Further, even in the present embodiment, the claim 11
A magnet may be provided as the detected part and a hall element may be provided as the overrun detector as in the embodiment of the invention described above.

[0086]

According to the first aspect of the present invention, the overrun detector and the detected body are provided on the rotated body which is separated from the drive shaft that directly drives the joint such as the wrist of the articulated robot. Therefore, it is possible to prevent the structure around the drive shaft from becoming complicated. Further, since the rotation of the rotating shaft is decelerated and transmitted to the rotated body, the rotating body can regulate the rotation of the rotating shaft with a smaller amount of rotation than the rotation of the rotating shaft. Therefore, if an overrun detector is provided at an arbitrary position on the fixed base, the rotation range of the rotary shaft can be easily regulated at 360 ° or more (one rotation or more).

According to the second aspect of the present invention, the rotating shaft can be reliably separated from the rotating body, and even if the rotating shaft is separated, the rotational force of the rotating shaft is transmitted to the rotating body via the belt. Since it is possible to secure a wide space around the rotary shaft, it is possible to greatly improve the degree of freedom in the mounting positions of the detected part and the overrun detector.

According to the third aspect of the present invention, for example, in the case where the radius of the rotating body is twice the radius of the rotating shaft, the reduction ratio is set to 1: 2 and the rotating shaft rotates once. Since the rotating body can be rotated by 1/2 rotation, if the overrun detector is attached to an arbitrary position on the fixed base, the rotation shaft can be easily regulated at a rotation of 360 ° or more. Further, if the radius difference between the rotating shaft and the rotated body is further increased and the reduction ratio is further increased, the range can be restricted when the rotating shaft rotates two times or more.

According to the fourth aspect of the invention, since the origin position detector is provided directly on the rotating body, not on the rotating shaft, the resolution can be made larger than when it is provided on the rotating shaft. It is possible to accurately detect the origin position. Specifically, when the radius of the rotating body is twice as large as the radius of the rotating shaft, it is possible to obtain twice the resolution as compared with the case where the origin position detector is provided on the rotating shaft. Also,
Since the detected part of the rotating body can be shared for overrun detection and origin position detection, it is possible to prevent the structure of the rotation restriction mechanism from becoming complicated, and the cost of the rotation restriction mechanism increases. Can be prevented.

According to the fifth aspect of the invention, the fan-shaped detected portion is detected by the direction detector when the detected portion moves to one side from the origin position detector when the rotated body rotates. In this case, it is detected that the detected device is located on one side.From this state, the rotary shaft should be rotated toward the origin position. When the fan-shaped detected part is not detected by the direction detector when the position is moved to, it is detected that the detected device is located on the other side, so from this state the rotation axis is rotated toward the origin position. By doing so, the time required for the rotary shaft to return to the origin position can be significantly shortened, and the rotary range of the rotary shaft (rotary range of the robot arm) can be minimized.

Further, even when the amount of rotation of the rotary shaft is counted by the incremental encoder, it is possible to easily return to the origin position, so that ordinary robot control can be performed at low cost. On the other hand, if an absolute encoder is used, it is possible to easily return to the origin position, but it is very expensive and not preferable for use.

According to the sixth aspect of the present invention, the rotation restricting range of the rotary shaft can be easily changed and adjusted, and the mounting position of the overrun detector can be arbitrarily set, whereby the rotary shaft It is possible to easily perform two or more rotations. According to the invention described in claim 7, when one of the overrun detectors fails and the rotating shaft runs away without detecting the rotating body by the overrun detector, the overrun detector is provided on the downstream side of the rotating shaft. The second detected portion can be detected by another normal overrun detector. Therefore, even if a failure of one overrun detector occurs, the rotating shaft can be reliably stopped, and safety can be significantly improved.

According to the eighth aspect of the invention, the rotation range of the rotary shaft can be made variable by changing the moving distance of the detected portion of the transmission belt and the distance between the driven shaft and the drive shaft.
The rotation range of the driven shaft (rotating shaft) at 360 ° or more can be restricted with a simple structure. As a result, the number of parts of the regulation mechanism can be reduced, and the cost of the rotation regulation mechanism can be reduced.

According to the ninth aspect of the invention, the rotation of the driven shaft can be decelerated and transmitted to the rotating body, and the rotation of the driven shaft of 360 ° or more can be easily allowed, and The rotation range can be regulated. Further, since the rotation range of the driven shaft can be regulated by using the transmission belt, the number of parts of the rotation regulation mechanism can be reduced and an inexpensive rotation regulation mechanism can be obtained.

According to the tenth aspect of the invention, since the origin position detector is provided directly on the rotating body, not on the rotating shaft, the resolution can be made larger than when it is provided on the rotating shaft. It is possible to detect the origin position more accurately. Also, since the detected part of the rotating body can be shared for overrun detection and origin position detection,
The structure of the rotation restricting mechanism can be prevented from becoming complicated, and the cost of the rotation restricting mechanism can be prevented from increasing.

According to the eleventh aspect of the present invention, the overrun detector detects an object to be detected that moves linearly with the rotation of the rotary shaft, thereby restricting the rotation range of the rotary shaft at 360 ° or more. Therefore, the structure of the rotation restricting mechanism can be simplified. Further, since the detected object can be linearly moved by the wire, it is possible to sufficiently cope with the case where the overrun detectors can be arranged in only one row.

According to the twelfth aspect of the invention, the overrun detector detects an object to be detected that moves linearly with the rotation of the rotary shaft, thereby restricting the rotation range of the rotary shaft at 360 ° or more. Therefore, the structure of the rotation restricting mechanism can be simplified. Further, since the detected object can be linearly moved by the wire, it is possible to sufficiently cope with the case where the overrun detectors can be arranged in only one row. Further, since the pulley is provided on the first wire wound around the rotary shaft and the one end of the second wire is provided on the first wire, the detected portion moves linearly in one direction or the other direction. The movement distance when doing can be halved compared to the one without a pulley, and the installation space for the rotation restricting mechanism can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of an articulated robot according to any one of claims 1 to 4;
It is the whole block diagram.

FIG. 2 is a configuration diagram of a main part thereof.

FIG. 3 is a view showing an embodiment of a rotation restricting mechanism of a rotary shaft of the articulated robot according to claim 5, and is a view showing an operating state of a rotated body thereof.

FIG. 4 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of the articulated robot according to claim 7, and is a diagram showing an operating state of a rotated body.

FIG. 5 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of the articulated robot according to claim 8 and its configuration diagram.

FIG. 6 is a diagram showing another aspect of an embodiment of the rotation restricting mechanism for the rotary shaft of the articulated robot according to claim 8 and is a configuration diagram thereof.

7A and 7B are views showing an embodiment of a rotation restricting mechanism of a rotary shaft of the multi-joint robot according to claim 9 or 10, wherein FIG. 7A is a configuration diagram thereof, and FIG. .

FIG. 8 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of the articulated robot according to claim 11 and its configuration diagram.

FIG. 9 is a diagram showing an embodiment of a rotation restricting mechanism of a rotary shaft of the articulated robot according to claim 12, and is a configuration diagram thereof.

[Explanation of symbols]

1, 41, 51 Rotating shaft 3 Driving shaft (rotating shaft) 3a Driving pulley (rotating shaft) 4, 23, 33 Transmission belt 5, 35 Rotating body 5a, 35a Projection (detected part) 6, 34, 52 Fixed base 7, 8, 25, 26, 37, 38, 45, 46, 58, 59 Overrun detector 9, 36 Origin position detector 11 Fan-shaped protrusion 12 Direction detector 14, 15 Second protrusion 22, 32 Drive shaft 24, 44, 57 Metal piece (detected part) 42 Wire 43, 56 Tension spring (biasing member) 53 Wire (first wire) 54 Pulley 55 wire (second wire)

Claims (12)

[Claims] 1. A rotary base rotation restricting mechanism for restricting rotation of a rotary shaft constituting a joint part of an articulated robot within a predetermined range, and a fixed base provided at a position separated from the rotary shaft, and the fixed base. Is rotatably provided to the rotary shaft and is connected to the rotary shaft through a rotary force transmitting means, and the rotational speed of the rotary shaft is reduced and transmitted to thereby rotate the rotary body at a lower speed than the rotary speed of the rotary shaft. And an overrun detector provided on the fixed base, and an overrun detector provided on the fixed base for detecting an overrun of the rotating shaft by detecting the detected part. A rotation control mechanism for the rotation axis of the articulated robot. 2. The rotating force transmitting means comprises a rotating shaft and a transmission belt wound around the rotating body, and the rotating force of the rotating shaft is transmitted to the rotating body via the transmitting belt. The rotation restricting mechanism for the rotating shaft of the articulated robot according to claim 1. 3. The rotation of the rotating shaft of the articulated robot according to claim 1, wherein the radius of the rotating body is n (where n is 1 or more) times the radius of the rotating shaft. Regulatory mechanism. 4. An origin position detector for detecting the detected position as an origin position of a rotary shaft when the fixed base is detected is provided on the fixed base, and the overrun detector is the origin position detector. The rotation restricting mechanism for the rotary shaft of the articulated robot according to claim 1, wherein the rotation restricting mechanism is provided in both directions of the rotating body with the pinch in between. 5. A fan-shaped detected portion provided on the rotated body, and a direction detector provided on a fixed base for detecting the detected portion, the fan-shaped detected portion comprising: When the detected part detected by the overrun detector is in the rotation direction of one side or the other side of the rotated body with respect to the origin position detector, the detected direction is detected by the direction detector. The rotation restricting mechanism for the rotating shaft of the articulated robot according to claim 4, wherein the rotation restricting mechanism is provided at a predetermined position of the rotating body. 6. The rotation restricting mechanism for a rotary shaft of an articulated robot according to claim 4, wherein the mounting positions of the overrun detector and the origin position detector can be varied on a fixed base. 7. The articulated robot according to claim 1, wherein a second detected portion is provided in a rotated body portion on the downstream side in the rotation direction with respect to the detected portion. Rotational axis rotation control mechanism. 8. A rotation shaft rotation restricting mechanism for restricting rotation of a rotary shaft constituting a joint part of an articulated robot within a predetermined range, the driven shaft being connected to a drive shaft via a transmission belt. The drive shaft is separated from the driven shaft so that the drive shaft is located at an inter-axis distance longer than the peripheral length of the driven shaft, and the detected portion is provided at a predetermined position of the transmission belt, and the drive shaft and the driven shaft are A rotation restricting mechanism for a rotary shaft of an articulated robot, characterized in that an overrun detector capable of detecting a detected portion is provided between the two. 9. A rotation shaft rotation restricting mechanism for restricting rotation of a rotary shaft constituting a joint part of an articulated robot within a predetermined range, the driven shaft being connected to a drive shaft via a transmission belt. A tooth having a predetermined pitch is formed on the inner peripheral surface of the transmission belt, and a tooth having a pitch larger than the pitch of the inner peripheral surface is formed on the outer peripheral surface of the transmission belt, and the tooth is fixed to the outer peripheral surface of the transmission belt. A table, a rotating body that is rotatably provided on the fixed table and meshes with teeth of the transmission belt, a detected portion provided on the rotated body, and a detected portion provided on the fixed table. An overrun detector for detecting the overrun of a rotating body, and a rotation restricting mechanism for a rotating shaft of an articulated robot, wherein the overrun detector is provided. 10. The fixed base is provided with an origin position detector that detects the detected position as the origin position of the rotation axis when the detected portion is detected, and the overrun detector is the origin position detector. 10. The rotation restricting mechanism for the rotary shaft of the articulated robot according to claim 9, wherein the rotation restricting mechanism is provided in both directions of the rotating body with the pinch in between. 11. A rotation restricting mechanism for a rotating shaft, which restricts rotation of a rotating shaft constituting a joint part of an articulated robot within a predetermined range, wherein one end is fixed to the rotating shaft and the rotating shaft rotates. A wire that can be wound around and unwound from a rotating shaft, a biasing member that is provided at the other end of the wire and that linearly biases the wire, a detected portion that is provided on the wire, and An overrun detector that detects a detection unit to detect an overrun of a rotation axis, and a rotation restriction mechanism for a rotation axis of a multi-joint robot. 12. A rotation restricting mechanism for a rotating shaft, which constitutes a joint part of an articulated robot and restricts rotation of a rotating shaft rotatably attached to a fixed base within a predetermined range, wherein one end of the rotating shaft is The first wire is fixed and the other end is fixed to a fixed base, and the first wire is capable of being wound around and unwound from the rotary shaft as the rotary shaft rotates, a pulley provided on the wire, and one end A second wire attached to the pulley and having the other end attached to the urging member and linearly urged by the urging member; and a detected portion provided at a predetermined position of the second wire, An overrun detector for detecting a detected part to detect an overrun of a rotating shaft, and a rotation restricting mechanism for a rotating shaft of an articulated robot.