WO1988000515A1

WO1988000515A1 - Wrist mechanism of a robot used in a clean air atmosphere

Info

Publication number: WO1988000515A1
Application number: PCT/JP1987/000506
Authority: WO
Inventors: Nobutoshi Torii; Susumu Ito; Hiroshi Wakio
Original assignee: Fanuc Ltd
Priority date: 1986-07-15
Filing date: 1987-07-14
Publication date: 1988-01-28
Also published as: JPS6322290A

Abstract

Robot wrist mechanisms (8, 8a) mounted on the tip of a robot arm (6) of a robot (4) used in a clean air atmosphere, comprise wrist housings (10, 90) connected to a vacuum line that has a source of negative pressure; wrist-operating units (20, 100) provided at ends of the wrist housings (10, 90); motors (16, 96) provided in said wrist housings (10, 90) to actuate the wrist-operating units (20, 100); and reduction gears (24, 98). The boundary between the wrist housings (10, 90) and the wrist operating units (20, 100) is sealed with a labyrinth sealing means (54), and the output ends of the electric motors (16, 96) and the reduction gears (24, 98) are sealed with sealing means (32, 36, 50, 52, 114) to prevent the leakage of grease.

Description

Akira's book List mechanism of robots used in clean air atmosphere

The present invention relates to an improved structure of a robot list mechanism of an industrial robot, and particularly to an industrial robot (hereinafter, referred to as an industrial robot) suitable for use in a clean room maintained in a clean air atmosphere. This is a structure that prevents external leakage of dust and oil components in the list mechanism of a clean room robot.冃 ά

Conventionally, a swivel or non-swivel robot vertical axis, robot arm, mouth bot list, etc., movable part of the mouth as an industrial robot used in a clean room that maintains a clean air atmosphere The dust is prevented from being generated from the robot, and the wiring and piping around the robot movable parts are stored inside the robot body to remove dust sources from around the robot. Robots with various structures are provided for room robots. These clean room robots are used for manufacturing and assembling precision products, such as integrated circuit components.Therefore, lubrication used not only for dust but also for the internal operation mechanism inside the α-bot machine. Leakage of oil and grease must be avoided. In particular, the list mechanism and the robot hand and other working tools attached to the list mechanism must be precision products that are the target of the robot operation. It is necessary to provide a reliable dust-repellent structure and a structure to prevent oil from leaking, since there are many opportunities to approach the area.

However, in the conventional clean room robot, the robot body is connected to and connected to a vacuum line having a negative pressure source to maintain the inside of the movable part in a negative pressure state, and the friction between the moving parts inside the robot. Even if there is a structure that sucks fine dust generated by the vacuum line into the vacuum line to prevent it from leaking into the clean room, an operation that includes a drive source and a speed reducer in the robot list Especially enclosed in the reducer when the structure incorporates means: fits in a structure that completely prevents the leakage of lubricant and the leakage through the micro gaps in the mouth bot list to the outside Has not been provided yet. Disclosure of the invention

Accordingly, the present invention solves the above-mentioned problems in the cleaning mechanism for a clean room robot in which a speed reducer in which lubricating oil is sealed is built in the robot list. According to the present invention, in a robot list mechanism attached to the end of a robot arm of an industrial robot used in a clean air atmosphere, a robot having a pit pressure is provided. A list housing that is connected in communication, a list operation unit provided at one end of the list housing, a motor provided in the list housing for operating the list operation unit, and a low-speed A list operating means having a speed reducer, a boundary between the list housing and the list operating section is sealed with a labyrinth seal, and a reduction gear of the list operating means is provided. Dali force end - and structure sealed with scan seal Thus, a robot list mechanism for an industrial robot is provided. As described above, since a labyrinth seal is provided between the list housing that maintains the negative pressure state and the list operation section, fine dust can flow out from the inside of the list to the outside. It is possible to prevent the leakage of the oil component inside the list by the grease seal, and of course, the leakage of the lubricating oil component to the outside does not occur. Brief drawing; ^ description

The above and other objects, features, and advantages of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

FIG. 1 is a sectional view of a first embodiment of a robot list mechanism of a clean room robot according to the present invention;

Fig. 2 is a side view of the list machine, as viewed from the arrow II-II line in Fig. 1.

FIG. 3 is a front view showing the entire structure of a clean room robot to which the list mechanism is attached.

FIG. 4 is a sectional view of a second embodiment of the robot list mechanism of the clean room robot according to the present invention, and

FIG. 5 is a front view showing the entire structure of a clean room robot to which the list mechanism is attached. BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a sectional view of a robot list mechanism of a clean room robot according to a first embodiment of the present invention, and FIG. 2 is a list machine of the same. FIG. 3 is a side view of the structure seen from the arrow II-II line in FIG. 1, and FIG. 3 is a front view showing the entire structure of a clean room robot to which the list mechanism is attached.

Referring to FIG. 1 and FIG. 2, the list mechanism 8 of the clean room robot has a list housing 10, and the list housing 1 Q includes a support 10 a and the support 10 a. It is composed of lids 10b and 10c tightly fitted to the part 10a, and a list operation part 20 is movably held at one end of the support 10a, that is, at the front end side. The other end, that is, the rear end side, is formed as a circumscribed end to a robot arm (not shown in FIG. 1), and in the center, this list machine 8 is vacuumed via a mouth body. An opening 12 for communicating with the line to obtain a negative pressure state is formed. Reference numeral 14 denotes one of the connecting bolts to the robot arm. The support 10a holds an electric motor 16 (generally composed of a DC servomotor) serving as one operation source of the list operation section 20. The rolling force is transmitted from the pulley 18a attached to the power output 16a to the pulley 18c via the belt 18b. The drive shaft 22 to which the pulley 18 c is attached forms the input of the depression suppressing operation of the list operation unit 20, and the surface rolling force transmitted to the drive shaft 22 is reduced by the reduction gear. A configuration is adopted in which the signal is transmitted to the internal machine frame 2S of the list operation section 20 via the section 24. At this time, the inner machine frame 26 turns around the support 10a at a desired deceleration rate around the axis of the drive shaft 22. The inner machine frame 26 itself is rotatably held on the support 10a by bearings 28 and 30.The bearing 28 is formed by a well-known cross roller bearing. Since the bearing 30 is formed of grease-lubricated ball bearings, the seal 32 prevents leakage of the grease lubricant. On the other hand, since the bearings 24a of the reduction gear 24 and the bearings 22a of the drive shaft 22 are also greased, the outer end of the reduction gear holder 34 slides with the pulley 18c. Grease leakage is prevented by the seal 36 provided in the section. In other words, the lubricating grease sealed in the reduction gear 24 and other rotary operation elements is formed so as not to leak inside the list mechanism 8, and the two seals 32, 3 are formed. 6 is formed as a sealing member covered with a resin material (tetrafluoroethylene), so that these seals 32 and 36 do not generate fine dust due to wear. .

Now, the re-list operation part 20 is a rotary output member in which the internal machine frame 26 forms a list first operation part and forms a second operation part provided at the tip of the internal machine frame 26. A rotation output member 40 is provided so as to be rotatable about an axis orthogonal to the center of the drive shaft 22, and the rotation output member 40 is decelerated from the electric motor 42 housed inside the internal machine casing 26. It is configured to be driven to rotate at a desired deceleration rate via a speed reducer 44, and the speed reducer 44 has a grease lubricated bearing 46. The rotation output member 40 is rotatably held by a bearing 48. Therefore, seals 50 and 52 are arranged outside the bearing 46 and outside the bearing 48 to prevent the leakage of grease. In addition, a labyrinth 54 is formed on the mutual sliding part in the downward movement of the inner machine frame 26 of the list operation part 20 and the support body 10a to maintain the negative pressure state. From outside the list toward the inside of the storage mechanism 8 Since only the clean air flows in a minute amount, fine dust and oil components do not leak out from the inside of the list mechanism 8 to the outside. Although not explicitly shown in the figure, a labyrinth is formed in the same manner in the sliding portion between the outer end of the inner machine frame 26 and the inner surface of the rotary output member 40. In the part 20 as well, the fine air flow accompanying the erosion effect is formed from the outside of the surface transfer member 40 to the inside of the inner machine frame 26 through labyrinth, and conversely the inside The fine dust oil component is prevented from leaking from the outside.

As described above, according to the present invention, basically, dust and oil components, which cause contamination of precision instruments and precision parts, flow from the inside of the list mechanism to the outside of the clean room maintained in the clean atmosphere. It employs a glue that fundamentally eliminates the causes that cause it. Therefore, in this way, a configuration is adopted in which the cause of the deviation from the inside of the list machine is eliminated and the wiring and wiring are eliminated from the outer periphery of the mouth box body in the same manner as the conventional clean room mouth bot. I have. That is, in the present invention, a configuration is adopted in which the wiring for the electric motors 16 and 42 is stored inside the list mechanism 8 sealed with the lids 10b and 10c, as shown in the figure. For example, the wires 60a and 60b for the motor 42 are formed so as to be connected via the connector 62, and the wire 60a extends to the robot body side through the mouth bot arm, and the wire 60a. 0b is fixedly wired to the motor 42. Therefore, when mechanically connecting the list machine 8 to the robot arm, the wires 62a and 60b can be connected by the connector 62, and the wires 60s and 60b can be connected. Both are stored in the list mechanism 8. It is. When connecting or detaching the list mechanism 8 and the robot arm, the lid 10 and the arm 10c are detached from the support 10a and mechanically connected. The tight fitting connection between the lids 10b, 10c and the support 10a is appropriately sealed by a sealing means. Incidentally, reference numeral 64 denotes a list mechanism when a vacuum line is connected to, for example, a robot hand or the like connected to the rotation output member 40 of the list mechanism 8 to create a negative pressure state. This is a coupling stopper that allows the vacuum line to reach the robot hand from inside of Fig. 8. Reference numeral 6 denotes a signal connector for transmitting an electric signal to the robot hand and obtaining an electric detection signal.

FIG. 2 shows a state in which the list operation unit 20 of the list mechanism shown in FIG. 1 is restrained from lowering with respect to the list housing 10. An electric motor 16 for driving the suppression operation is shown.

FIG. 3 is a front view showing the overall shape of a clean room robot to which the list mechanism 8 according to the first embodiment is mounted. In FIG. 3, the list mechanism 8 is attached to the tip of a robot arm (the tip is slightly shown) that is retractably accommodated inside the robot arm section 6. The arm 6 is attached to the upper end of a vertical shaft (slightly indicated at the tip) housed inside the robot body 4. The vertical axis is configured to be capable of vertical movement and to be capable of turning around the vertical axis. The robot body 4 is fixedly fixed to the floor in the clean room. List operation part 20 of list mechanism 8 A suitable mouth bot work means, for example, a π-bot hand is attached to the rotary output member 40 in the above-mentioned manner, and the desired mouth bot work is achieved in a three-dimensional space.

FIG. 4 is a cross-sectional view showing another embodiment of a clean room robot list mechanism according to the present invention. In this embodiment, a single list operation section is provided. I have.

This list mechanism 8a has a hermetically sealed list housing 90 as in the previous embodiment, and this list housing 90 is

An electric motor 96 for driving the list operation unit 100 is formed on the support 92 and is formed of a cover 92 and a cover 94. The list operation section 100 is provided on the front end side of the list housing 90, and the rear end side is formed at the coupling end to the robot arm, as in the above-described embodiment. is there. The rotation output of the motor 96 is transmitted to the input bevel gear 102 at a desired reduction rate via the speed reducer 98, and the input operation bevel gear 102 has a restarting unit 100 from the input bevel gear 102. The direction of rotation is converted by the output level gear 104, and the list operation unit

It is configured to be transmitted to the rotation output member 106 of 100. Here, reference numeral 108 denotes a grease-lubricated bearing provided in the speed reducer 98, and 110 denotes an input bevel gear.

Reference numeral 102 denotes a bearing, and reference numeral 112 denotes a bearing for supporting the rotation of the rotary output member 106. Grease leakage prevention seals 114 are provided so that lubricating grease does not leak from the bearings 108, 110, and 112. In addition, the holding ring 118 attached in a sealed structure to the support 92 via the 0 ring 116 is used to hold the grease seal 114 and the bearing 111. , But A labyrinth structure is provided in a sliding portion 120 between the holding ring 118 and the rotation output member 106 to form a sealing structure. Accordingly, when the inside of the list mechanism 8a is maintained in the negative pressure state, the small holes 122 formed in the rotary output member 106 by the diameter of the labyrinth structure portion and the rotary output member are formed. A clean air flow from the outside of the list to the inside of the list housing 90 is formed through the center hole 1 24 of 106 and the inside of the list housing 90, and fine dust and dust from the inside of the list housing 90 to the outside are formed. Leakage of lubrication dust is prevented. When the list mechanism 8a is actually used, since a work tool such as a robot hand is attached to the outer end of the rotary output member 106, the center hole 1 of the rotary output member 106 is not used. 24 receives clean air flow from the outside only through the small holes 1 2 2.

FIG. 5 shows the appearance of a clean room robot to which the above-described list mechanism 8a of the second embodiment of the present invention is attached, similar to the case of FIG. 3 described above. The details are omitted here because of the configuration.

As is apparent from the above description, in the robot list mechanism of the clean room robot according to the present invention, neither fine dust nor lubricating clean components leak from the inside of the list mechanism to the outside. As shown in the figure, the wrist mechanism, which maintains the negative pressure as before, has a lapiling structure to allow a small amount of clean air to flow inward from the outside. It provides a robot list mechanism that is configured to prevent leakage of substances to the outside even if this is used, and that has a structure in which wiring and piping are housed inside. Clean room held in The result is a listing mechanism that is extremely suitable for use within a device. The reduction gear used for the list mechanism according to the present invention is the first reduction gear.

Both the first and second embodiments show an example in which a well-known harmonic drive device (trade name) is used, which is provided in a narrow space by being connected to a motor, and has a relatively small size. This is because it is suitable for obtaining a high deceleration rate.

Claims

Billing

1. In a robot list mechanism attached to the robot arm tip of an industrial robot used in a clean air atmosphere, a list that communicates with and is in contact with a vacuum line having a negative pressure source. List having a housing, a list operation unit provided at one end of the list housing, a motor provided in the list housing for operating the list operation unit, and a reduction gear Operating means, and labyrinth sealing means for sealing a boundary between the list housing and the list operating portion, and an output end of a speed reducer of the list operating means. A list mechanism for industrial robots, which is provided with a sealed leakage prevention seal means.

2. A first operation part in which the list operation part rotates about a first axis with respect to the list housing, and a second operation part in which the list operation part rotates about a second axis with respect to the first operation part. The industrial device according to claim 1, further comprising an operating portion, wherein a boundary between the list housing and the first and second operating portions is both sealed by the lip seal. Robot list mechanism.

3. The first operating section is provided with the rotation operating means of the second operating section, and the output end of the speed reducer of the rotary operating means is sealed by the grease leakage preventing seal means. 3. The list mechanism for an industrial robot according to claim 2.

4. The industrial robot list mechanism according to claim 3, wherein the reduction gear of the list operation means and the reduction gear of the rotary operation unit each comprise a harmonic drive device.