JPS6021190Y2 - Burnable arm device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to, for example, an arm device for a robot, and the arm device is configured to be flexible.

For example, a robot arm with a spray gun for painting or a torch for welding at its tip needs to scan a plane over a certain range, so it has two degrees of freedom to move the arm freely within this plane. However, in the past, (a) it was a non-flexible link connection, so it was not possible to get around to narrow spaces, and (b) the center of rotation of the arm's two degrees of freedom was at two points. (c) Since the drive mechanism is used as a movable member and mechanical member, the overall shape has to be large, making it difficult to work in narrow spaces. There are problems such as.

By the way, there is a device in which the arm is configured to be flexible, as disclosed in Japanese Patent Application Laid-Open No. 111158/1983 (referred to as the prior art), but this prior art has a complicated mechanism and is difficult to manufacture. In addition to being difficult and expensive,
Flexibility is ensured by the link mechanism, so
There is a limit to the number of links (link pitch length), and when curved, the links become straight lines, so the curvature during rotation becomes a polygon, and the curvature cannot be made sufficiently small.

Therefore, the present invention solves the above problem by providing an arm device that has two degrees of freedom and can obtain sufficient scanning accuracy despite not having a drive mechanism at the tip of the arm device. The purpose is to achieve this goal.

According to the present invention, the purpose is to provide at least two coil springs, a connecting device for stacking the coil springs in a height direction and connecting them to each other, and one of the rows of coil springs connected to the connecting device. a base to which the end of the coil spring located at the end of the coil spring is connected, and one end of the coil spring is connected to the base at an axial center position of the base and the connector in order to connect the base and the connector. a first connector that is fixed to either one of the connectors and whose other end is rotatably connected to the other of the base and the connector; and the other of the rows of coil springs. At the axial center position of the end fitting and the connecting tool, one end is connected to the end fitting and the end fitting is connected to the end of the coil spring located at the end of a second connector that is fixed to either one of the connectors and whose other end is rotatably connected to the other end of the end fixture and the connector; and the first and second connectors. a through hole provided in the connecting tool that is provided outwardly from a position where the tool is provided and that penetrates in the height direction of the coil spring at a position inside the coil spring; and one end of the end tool. and a flexible string-like body inserted into the through hole of the connecting tool, and a flexible string-like body connected to the other end of the flexible string-like body to pull the flexible string-like body and said base. It is closely related to a flexible arm device characterized in that it consists of a tensioning means provided on a platform.

Next, the present invention will be explained based on preferred embodiments shown in the drawings.

A base connector 1 serving as a base has a mounting portion 4 having a groove 3 on its outer periphery into which a helical helical winding of a spring 2 made of a coil spring can be screwed, and is fixed to an actuator 5.

A bearing member 7 having a sphere 6 at one end is screwed into the center of the mounting portion 4 .

The basic connector 8 has a groove 10 on its outer periphery into which a helical helical winding of a spring 9 made of a coil spring can be screwed. The groove 10 of this basic connector 8 has the same shape.

The groove 10 can, on the one hand, screw in two or three turns of the helical winding of the spring 2, and on the other hand, can screw the helical winding of the spring 9 located adjacent to and above the spring 2 with two or three turns. The axial length is determined according to the degree.

A large diameter hole 11 is bored in the central lower end of the basic connector 8, and a bearing 12 having a spherical surface is disposed inside this hole 11.
The ball 6 of the bearing member 7 is accommodated in the bearing 12 to form a universal joint.

Further, a small diameter screw hole is provided at the upper center end of the connecting tool, and a bearing member 7 having a ball 6 at the tip is screwed into the connecting tool for connecting a separate connecting tool with a universal joint.

In this specific example, as the third connector that interconnects the first and second connectors and the basic connector 8, the spring 2 and the universal joint described above are used as in the past. 9
are formed from the same number of turns, with the same diameter d1 and the same length 1. As shown, the portions of the helical windings that are threaded into each groove 3.10 are in close contact with each other, and the portions that are located between one connecting device and another connecting device are The helical windings are axially stretched slightly and spaced apart from each other.

It is preferable to keep the helical windings separated between the connectors in this way, because the bending can be facilitated, and the arm device can be operated with a small force applied to the actuator 5.

The required number of basic connectors 8 are of the same shape, 3 in the example shown in Figure 1.
Connect the pieces one after another in the same way as above.

A spring 13 made of a coil spring is screwed into the groove 14 of the basic connector 8 located at the top, and a tip connector 15 to which a spray nozzle, welding torch, etc. is attached is connected to the spring 13.

In this example, the groove 14 provided in the upper half of the basic connector 8 located at the top and the groove 10 provided in the lower half have different groove widths, and the groove 14 in the upper half is located downward. The structure is such that a spring 13 having a wire diameter larger than that of the spring 2.9 can be screwed into the spring 13.

In this way, if the spring 13 located at the top has a larger wire diameter and its total length is longer than the total length 1 of the springs 2 and 9, the spring constant of this spring 13 will be the same as that of the other springs 2 and 9. It is larger than the spring constant.

A hole 11 is provided at the center lower end of the end fitting 15 as this end fitting.
A bearing 12 having a spherical surface is disposed in the hole 11, and the spherical body 6 of the bearing member 7 protruding from the basic connector 8 located below is received in the bearing 12.

A groove 16 into which the helical winding of the spring 13 is screwed is provided on the outer periphery of the tip connector 15.
are screwed together to connect the connector 15.

Flexible string-like bodies 20 are fixed at four locations that equally divide the circumferential direction of the tip connector 15, and the basic connector 8
A through hole 21 passing through the base connector 1 in the axial direction is provided at each of four locations, and the string-like body 20 is inserted into the through-hole 21, and the other end of the string-like body 20 is provided in the actuator 5. It is connected to a piston 23 that slides within the cylinder 22.

In the example of FIG. 1, two cylinders 22 and two pistons 23 are shown in the actuator 5, but the remaining two cylinders and pistons are arranged in the front-rear direction perpendicular to the paper surface in the same way as in FIG. Since each string-like body 20
are connected to the piston 23 independently.

In this way, the other end of the string-like body 20 is connected to a tensioning means consisting of a piston 23 that slides within a cylinder 22 provided in the actuator 5.

Further, the actuator 5 itself is twisted and rotated in the direction 24 in the figure or in the opposite direction 25 by a method known per se.

When using the arm device of the present invention with the above configuration,
Connect the required basic connector 8 to the base connector 1 and the tip connector 15.
Bearing member 7 of the connecting tool located below and interposed between
Bearing 1 of a connecting tool to which a sphere 6 provided above is to be connected
2, and on the other hand, the springs 2, 9.13 are screwed into the grooves 3, 10.16 provided on the outer periphery of the attachment part 4 and the outer periphery of the connecting device, respectively, as described above, to assemble the arm device.

In use, for example, if the piston 23 in the right cylinder of the cylinders 22 in the actuator 5 in FIG. 1 is moved downward from the middle position and the left piston is moved upward at the same time, the right string The tensile force applied to the tip fitting 15 causes the tip fitting 15 to
It rotates to the right around the sphere 6 provided on the bearing member 7 of the basic connector 8 located just below the base connector.

This rotation compresses the right side of the spring 13 and tensions the left side.

The compressive force and tensile force of this spring 13 are transmitted to the basic connecting device 8 immediately below, and this basic connecting device 8 also rotates to the right.

Thereafter, all the basic connectors 8 are rotated to the right in the same way, and the second
It will be in the state shown in the figure.

When the actuator 5 operates in the opposite direction to the above, the tip fitting 15 rotates to the left, and the basic connecting fitting 8 located below it also rotates to the left in the same manner as described above.

Furthermore, as mentioned above, since the two string-like bodies 20 are engaged with the actuator 5 in the front-back direction perpendicular to the plane of the drawing, the end connector 15 also rotates in the front-back direction, and the arm rotates. It will rotate left and right and front and back.

Since the actuator 5 itself can be rotated around the vertical axis during this rotation, the arm device can obtain a motion that is a combination of torsional rotation.

Note that when each of the connectors rotates, the string-like body 20 and the connector come into contact and the cord-like body 20 is bent, for example, points 26 and 27 in FIG. The position is always symmetrical with respect to the center point 28 of the sphere 6, which is located at the center of rotation when the connecting tool rotates, and the length of movement of the string-like bodies 20 and 20 is arranged to be the same. be.

The same applies to the other contact points of each connector, and in a specific example, as shown in FIG. It is preferable to form the hole 31 with a diameter slightly larger than the outer diameter of the shaped body.

That is, by forming it from a separate member, it is possible to use a metal with high wear resistance only in this part, or by providing a roller or the like in the hole 31, the string-like body and/or this weaving point can be used. On the other hand, with a hole having a diameter slightly larger than the outer diameter of the string-like body 20, the distance from the ball center 32 to the inner surface 31a of the hole 31 can be easily configured to prevent wear. From the ball center 32 to the outer surface 3 of the hole
As a result, the connecting tool rotates to the right, and the string-like body 20 contacts the outer surface 31b at the hole on the right side, and the string-like body 20 contacts the outer surface 31b at the hole on the left side. This is because even if the body contacts the inner surface 31a, the amount of movement of the string-like bodies located on both sides can be made substantially the same.

In the above example, the actuator is shown as having a cylinder and a piston that slides in a linear direction within the cylinder, but a rotary actuator may be used instead.

Further, although a universal joint made of a sphere and a spherical surface is illustrated, a double pin joint universal joint may be used instead.

Although the string-like body is inserted through a through-hole provided inside the connector, it can alternatively be positioned outside the spring.

This increases the stroke of the actuator.

The four string-like bodies may be individually fixed to the tip fitting, or the four string-like bodies may be formed as one string-like body located opposite to each other in the 1800 direction, and the center thereof may be fixed to the tip fitting. You may also do so.

According to the flexible arm device of the present invention configured as described above, the following effects are achieved.

(1) Compact and simple structure.

(11) Since rotation is transmitted using a flexible string-like body and a spring, the radius of rotation can be made small and flexibility is excellent.

(iii) Also, if the connector and the spring are interconnected by screwing as in the specific example, even if the springs have the same spring constant,
By changing the screwing amount, the spring constant of the expanding and contracting part can be changed.

Therefore, it is possible to partially rotate more or less.

It can also transmit a large amount of the force of its own weight.

(IV) Since the rotational force is transmitted by a spring, the transmitted force can be partially selected arbitrarily by selecting the spring constant.

(V) The combination of the universal joint and the spring allows the synthetic leather to be easily rotated from side to side, back and forth, and torsionally.

(vD Even if the string-like body is broken, the restoring force of the spring can prevent the arm device from sagging due to its own weight.

(Vll) Since the string-like body is provided inside the spring, the spring serves as a protective member for the string-like body, and can prevent damage to the string-like body.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the flexible arm device of the present invention, and the X-X cross-section also has the same configuration, Figure 2 is an explanatory diagram showing the state in which it is rotated in one direction, and Figure 3 is a diagram showing the string. FIG. 3 is a cross-sectional view showing an example of a configuration at a contact point between the shaped body and the connector. 1... Base connection tool, 2, 9, 13...
・Spring, 6...Ball, 7...Bearing member, 8...Basic connector, 12...Bearing, 15...Tip Connecting tool, 2o... String-like body.

Claims (2)

[Scope of utility model registration request] (1) At least two coil springs, a connecting device that stacks the coil springs in a height direction and connects them to each other, and a coil located at one end of the row of coil springs connected to the connecting device. A base to which ends of the spring are connected, and one end of the spring connected to the base and the connector at an axial center position of the base and the connector to connect the base and the connector. a first connector fixed to one of the coil springs, the other end of which is rotatably connected to the other of the base and the connector; and a first connector located at the other end of the row of coil springs. At an axial center position between the end and the connecting tool, one end connects the end to which the end of the coil spring is connected, and the end and the connecting tool are connected to each other. a second connector, the other end of which is rotatably connected to the other of the end and the connector; and the first and second connectors. a through hole provided in the connecting tool that is provided outwardly from the position where the connecting tool is located, and that penetrates in the height direction of the coil spring at a position inside the coil spring, and one end is fixed to the end portion; a flexible string-like body inserted into the through-hole of the connector; and a flexible string-like body connected to the other end of the flexible string-like body so as to pull the flexible string-like body, and provided on the base. A flexible arm device comprising: a tensioning means; (2) There are three or more coil springs, a third connector is provided between the connectors between the base and the end, and one end of the third connector is connected to the third connector. The other end of the third connector is rotatably connected to the other of the connectors that sandwich the third connector therebetween. The flexible arm device according to claim 1, characterized in that the flexible arm device is characterized in that: