JP2551678Y2 - Articulated robot with weight balance device - Google Patents

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an articulated robot provided with a weight balance device using an air cylinder.

2. Description of the Related Art Conventionally, an articulated robot provided with a weight balance device of this type has a first joint, such as shown in FIG.
The arm 12 is swingably supported on the shoulder 11 on the support base side,
Between the shoulder 11 and the first arm 12, the balance cylinder 3
0, the balance cylinder 30 is connected to an air source 44 by a line 40 provided with a pressure reducing valve 41 with a relief, and a check valve 42 is further provided in the line 40, and an on-off valve 43 provided in parallel with the check valve. An air tank 46 is connected to the conduit 40 between the check valve 43 and the vanance cylinder 30 so that the air pressure in the balance cylinder increases as the first arm 12 deviates from the neutral position, so that the optimum weight compensation is always performed. Has become.

However, in such a conventional technique, it is necessary to provide an air tank.
The position of the air tank needs to be a position that does not hinder the operation of the robot and that does not increase the weight of the movable part such as the first arm.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a rib inside a swivel.
Seal the space enclosed by the integrally formed side walls with a lid
To form an air tank.
Connected to the line between the cylinder and the valve, and
And a balance cylinder connected via a swivel table .

[Function] A side wall integrally formed with a rib inside the swivel base.
Air tank formed by sealing the space enclosed by
Is supplied with pressurized air through a valve, and compressed air is further supplied through a pipe to a balance cylinder. Then, as the arm is displaced from the neutral state, the weight imbalance increases, while the volume of the cylinder on the side where the compressed air of the balance cylinder is introduced decreases, but the backflow through the pipeline is prevented by the valve, so The air pressure in the air tank rises, so that optimum weight compensation is always performed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, reference numeral 10 denotes a fixed support, on which a shoulder 11 is rotatably supported about a vertical first axis O1.
The base end of the first arm 12 is supported on the shoulder 11 so as to be rotatable about a horizontal second axis 02, and is rotated by the second servo motor 21.
A second arm 13 is rotatably supported on the distal end of the second arm 13 about a third axis 03 parallel to the second axis 02, and is rotated by the third servomotor 22 via the arm 16 and the link 17. . A vent wrist 14 and a swivel wrist 15 are sequentially rotatably supported at the distal end of the second arm 13 and are rotated by fourth and fifth servo motors 23 and 24, respectively. As shown in FIG. 1, a balance cylinder 30 is provided between the shoulder 11 and the first arm 12. The lower end of the cylinder body 31 of the balance cylinder 30 is connected to the bracket 18 fixed to the shoulder 11 via a pivot pin 34, and is connected near the tip of the piston rod 32. The center axis of each pivot pin 33, 34 is the second axis.
It is parallel to the axis O2, and is in a plane connecting the second and third axes O2 and O3 in the neutral state shown in FIG.
The balance cylinder 30 operates so that the piston rod 32 is pulled out as the first arm 12 swings about the second axis O2 and inclines from the vertical neutral position. Compressed air is supplied to a cylinder chamber above the piston of the decreasing balance cylinder 30 through a pipe 40 described below. Although not shown, the cylinder chamber below the piston is communicated with the atmosphere. As shown in FIG. 1, both ends of the conduit 40 are connected to an air source 44 provided with a shut-off valve 45 and an upper cylinder chamber of the balance cylinder 30 by connecting portions 47 and 48, respectively. The pipe 40 is provided with a pressure-reducing valve 41 with relief and a check valve 42 from the connection portion 47 side to be connected.
An open / close throttle valve 43 is provided in parallel with the second throttle valve 2. Further, a branch 40 a provided in the pipe 40 between the check valve 42 and the vanance cylinder 30 is connected to the air tank 46 via a connecting portion 49. As shown in FIGS. 2 and 3, the air tank 46 is formed by sealing a space defined by reinforcing ribs 10 a inside the fixed support base 10 with a lid 50. Next, the operation of the above embodiment will be described. In a normal use state, the closing valve 45 is opened, and the opening / closing throttle valve 43 is opened.
Is closed, the compressed air from the air source 44 is reduced to a predetermined pressure by the pressure reducing valve 41 with relief, and is supplied to the upper cylinder chamber of the balance cylinder 30 and the air tank 46 through the check valve 42 and the pipe 40. . With the operation of the articulated robot, as the first arm 12 is displaced from the vertical neutral position and tilts, the weight imbalance of the portion beyond the first arm 12 increases. The balance cylinder 30 pulled out according to this tilt is increased. Piston rod 3
2 is provided with a force opposing the drawer by air pressure applied to the upper cylinder of the balance cylinder 30, thereby compensating for weight imbalance and reducing the load applied to the second servomotor.

[Effects of the Invention] As described above, the present invention has a rib inside the swivel base.
Since the space enclosed by the side walls formed integrally with each other is sealed with a lid to form an air tank, it can be easily formed without increasing the weight of the robot, and a necessary and sufficient volume can be obtained. There are advantages. In addition, it is an integrated structure
Therefore, the assembling process can be simplified, and
There is no risk of interference with the department. In addition, an air tan on the swivel
The pipe is connected via the fixed base and the swivel base.
The pipe can be connected smoothly to the balance cylinder
Has good durability.

[Brief description of the drawings]

FIG. 1 is an overall view of a weight balance device according to the present invention.

FIG. 2 is a sectional view of a main part of the weight balance device according to the present invention;

FIG. 3 is a plan view of a main part of the weight balance device according to the present invention;

FIG. 4 is an overall view of a conventional weight balance device.

[Explanation of symbols]

 Reference Signs List 10 fixed base 10a rib 11 shoulder 12 arm (first arm) 30 balance cylinder 42 check valve 46 air tank 50 lid

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-4375 (JP, A) JP-A-3-36789 (JP, U) JP-A-1-125192 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A solid Sadamoto swivel base to base is rotatably mounted an upright axis as the central axis, and A over arm which is swingably supported on a shoulder formed on the swivel deck, said shoulder and balance cylinders provided between the <br/> arm and part to compensate for the accompanying caused weight imbalance in the displacement from the neutral position of the arms, conduits for supplying compressed air which is adjusted to a predetermined pressure in the balance cylinder When the ribs the in articulated robots with more becomes weight balance device and to that valve retaining the compressed air supplied to the balance cylinder, inside the swivel deck
The space enclosed by the side walls integrally formed by the above is sealed with a lid to form an air tank.
Connected to the pipeline between the sense cylinder and the valve,
The pipe line is passed through the fixed base and the swivel base.
An articulated robot having a weight balance device connected to a balance cylinder .