KR0123894B1 - Robot arm coupling apparatus - Google Patents

Abstract

The device consists of an internal assembly (2) attached to the robot arm, an external assembly (3) to which a tool or other tool is attached, and a fixing device for fixing the two previously assembled assemblies, respectively. A piston member 16 smoothly supported by the inner assembly 2 between the fixed position and the release position, a plurality of ball members supported by the inner assembly 2 around the aforementioned piston member 16, and The electric fixing device, which consists of a ball retainer 32 attached to the outer assembly 3, can contact the tapered surface with the ball member 12, so that the two assemblies remain connected and the piston member When the 16 moves to the fixed position, the ball member 12 is engaged with the ball member 12. The contact surface of the piston member 16 together with the ball member 12 is a tapered surface at least in that part.

Description

Robot arm connection device

1 is a vertical cross-sectional view showing a state in which the inner assembly and the outer assembly are connected to each other.

2 is an enlarged cross-sectional view of main parts of the apparatus according to the present invention.

The present invention relates to a connecting device of the robot arm, and more particularly, to a connecting device capable of quickly attaching or degassing a tool or other tool to the robot arm.

Generally, the connecting device is known as an inner assembly attached to the robot arm, an outer assembly to which a tool or other tool is attached, and a connecting device for attaching or degassing a tool or other tool to the robot arm. And a fixing device for fixing the outer assembly to the inner assembly.

For example, U.S. Patent No. 4696524 describes a piston member supported by an inner assembly smoothly between a fixed position and a release position, and a plurality of ball members supported by the inner assembly around the aforementioned piston member. member) and a ball retainer supported by the outer assembly, which can come into contact with the electrical ball member of the outer assembly on a tapered surface, so that the piston member moves to the locked position. It shows a connecting device with a fixing device that maintains the connection state by connecting and supporting the assembly and the ball member to each other. When the piston member is moved to the fixed position by this device, the ball member pushes the outer assembly upward through the center of the tapered surface, where the inner assembly and the outer assembly are in a fixed state, respectively. In the above connection, even if the piston member is in the fixed position, the cylindrical surface extending in parallel with the smooth part of the piston member is in contact with the ball member. Therefore, if the inner assembly and the outer assembly are operated irregularly, The member cannot move accurately to the fixed position. Therefore, there is a problem that the contact surfaces of the two assemblies are not exactly matched while the inner assembly and the outer assembly are fixed.

SUMMARY OF THE INVENTION An object of the present invention is to improve the connection device of the robot arm described above by preventing clearance from the contact surface of both assemblies in a fixed state and preventing movement to an incorrect fixed position. It is still another object of the present invention to provide a robot arm connecting device having an inner assembly and an outer assembly that accurately move to a fixed position and a release position without irregular deviation between the inner assembly and the outer assembly.

In order to achieve the above object, the connection device of the robot arm according to the present invention is an internal assembly to be attached to the robot arm, an external assembly to which a tool or other tool is attached, and a fixing device to fix each of the two assemblies. It is. An electrical system consisting of a piston member which is smoothed between a fixed position and a release position and supported by the inner assembly, a plurality of ball members supported by the inner assembly around the electric piston member, and a ball retainer fixed to the outer assembly. One holding device can be in contact with the ball member, which is electrical at the tapered surface, so that when the piston member is moved to the fixed position, the two assemblies and the ball member are connected and supported with each other to maintain the connection state. At least one portion of the surface on which the piston member is connected to the ball member is the first tapered surface. Therefore, when the piston member is moved to the locked position, the piston member first presses the ball member through the middle portion of the tapered surface. As a result, the ball member is pressed by the wedge effect by the tapered surface, and the pressure is pushed outward from the radial direction. Will receive. Then, the ball member pushes the outer assembly outward through the middle portion of the tapered surface, that is, by pressing toward the inner assembly, the two assemblies are fixed with no gap between them. While the ball is pushed outward in the radial direction by the tapered surface of the piston, the advancing malfunction is eliminated and the fixing of both assemblies is done accurately without the gaps occurring at the contact surfaces of both assemblies, that is, the fixed position The reproduction of incorrect operation in the system is improved. In the present invention, the contact surface of the piston member with the ball member is a cylindrical surface first connected to the lower side of the tapered surface. Even if the piston member is not supported at the predetermined position and the ball member pushes the inner assembly radially and lifts the piston member, the cylindrical surface is connected under the tapered surface, so that the separation between the inner assembly and the outer assembly is prevented. Is suppressed, and the force of the ball member lifting the piston in that portion becomes ineffective.

In the present invention, the cylindrical surface of the piston member is connected to the second tapered surface from below, and the taper angle of the first tapered surface tapered with respect to the vertical axis is smaller than the taper angle of the second tapered surface tapered with respect to the vertical axis. It is. In this case, for example, the taper angle of the first tapered surface tapered with respect to the vertical axis is about 15 degrees, and the taper angle of the second tapered surface tapered with respect to the vertical axis is about 30 degrees. If the taper angle of the first tapered surface is larger than the taper angle of the second tapered surface, the inner assembly and the outer assembly are fixed with relatively few strokes, respectively, so that the ball member may be pushed outward in the radial direction. When the taper angle of the first tapered surface with respect to the vertical axis is small, the wedge effect of the first tapered surface being widened to be fixed even if there is an unexpected movement of the robot arm can be maintained accurately.

In the present invention, the piston member is composed of three parts, that is, a large diameter first part, a large diameter second part having a tapered surface in contact with the ball member, and a first part connected to the second part. It consists of a small diameter third part. This structure of the piston member provides a piston of a wide surface so that pressure is applied to the piston, and the piston can be operated with great force by accepting the elongation at this time, and the operation of the piston is quick and accurate. More specifically, for example, by making compressed air supplying air to the upper and lower surfaces of the piston member of the large-diameter first part, that is, the fixing and releasing of both assemblies can be operated accurately.

Further features and novel objects of the invention will be clearly understood by reading the description with reference to the drawings.

An embodiment of the present invention will be described with reference to the drawings.

1 is a cross-sectional view showing the connecting device of the robot arm in a fixed state, and reference numeral 1 denotes an inner assembly 2 connected to a robot arm (not shown) and an outer assembly 3 to which a tool or other tool is attached. The robot arm connecting device is displayed.

Both assemblies 2 and 3 are constituted in this way, and the attachment and degassing of these assemblies are performed quickly. In the inner assembly 2, a master cylinder 13 supporting four steel balls is attached to the master body 11 with screws 14. The holes 15 of the small diameter 15a and the large diameter 15b connected to the same shaft are in the master body. The piston 16 smoothly enters the small diameter 15a of the hole 15. More specifically, the piston 16 has a piston main body 16a that smoothly enters the hole 15 of the small diameter 15a through the center of the o-ring 17, and the piston main The master cylinder 13 and the rotating ball 16c which are composed of a shaft 16b having one end connected to the body 16a, and connected to the other end of the shaft 16c fixed by the screw 18. ), It pushes the ball 12 radially outward.

In this operation, for example, the piston 16 has a function of reciprocating motion in the vertical direction by the compressed air, and a function of a reciprocating cam which makes the ball 12 reciprocate in the radial direction.

The sealing materials 19 and 20 are provided between the master cylinder 13 and the shaft 16b, and between the master cylinder 13 and the master body 11, respectively. The fixing pin 21 is attached to the master cylinder 13 and extends downward through the master cylinder 13.

Although not clearly shown in the drawing, the ball 12 is prevented from slipping out of the master cylinder 13 by a leaf spring attached to the outer circumferential surface of the master cylinder 13. A ring-shaped groove 11a into which the sealing material 22 enters is made above the master body 11, and a master cannector 23 is attached to the side of the master body 11.

The ball rotating body 16c is connected to the cylindrical portion 16d of the large diameter which slides into the circular recessed portion 13a of the master cylinder 13, the first tapered surface and one end thereof to the cylindrical portion 16d, and the other. A tapered conical portion 16e is provided which is configured to have a smaller diameter toward the end portion, so that the small diameter cylindrical portion 16f is connected to the other end of the tapered portion 16e, and to the second tapered surface. The tapered portion 16g is connected to the small diameter cylindrical portion 16f. The taper angle of the tapered cone portion 16e with respect to the vertical axis (hereinafter referred to as the taper angle of the tapered cone portion) is the taper angle of the tapered portion 16g with respect to the vertical axis (hereinafter referred to as taper angle of the tapered portion 16g). In this embodiment, the taper of the conical tapered portion 16e is used in order to increase the wedge effect due to the tapered cone portion (described later) and to accurately maintain the fixed state from the sudden operation of the robot arm. The angle was designed to be smaller than the taper angle of the tapered portion 16g. Specifically, in this embodiment, the tapered angle of the conical tapered portion 16e is 15 degrees, and the tapered angle of the tapered portion 16g is 35 degrees. The outer assembly 3 with the tool post consists of an upper member 31a, a lower member 31b, and a ball retainer made to contact the ball 12. The ball retainer 32 is annular.

What is formed inside the circumferential surface of the ball retainer 32 is the tapered surface 32a made to contact the ball 12. A fixing hole 32b to which the fixing pin 21 on the upper surface of the inner assembly 2 is fixed is made together.

Attached to the upper member 31a of the tool rest 31 is a rubber bushing 33 installed upward from the upper end of the tapered portion 33a. When both assemblies 2 and 3 are fixed, the upper end of the taper portion 33a is fixed to the recess 11b of the master body 11, and the device has an air hole for adjusting the movement of the tool. 34 is formed. Reference numeral 35 denotes a tool connector which is electrically connected to the master connector 23 when the two assemblies 2 and 3 are respectively fixed. This electrical connection constitutes an electrical control system for manipulating the tool.

In the above configuration, there is a device similar to the conventional device (US Patent No. 4696524), but when the inner assembly is fixed to the outer assembly, a piston (not shown) is provided through an air hole (not shown) in the master body 11. 16) When the compressed air is supplied to the upper surface of the piston main body 16a, the piston descends and comes into contact with the inside of the ball 12. Therefore, the second tapered surface of the ball rotating body 16c (taper portion 16g) ), The taper angle is large, and the stroke in the vertical direction is small, so the ball 12 is out of the radial direction.

The outer surface of the ball is pressed by the first tapered surface (tapered conical portion 16e), which is why it is called the wedge effect by the first tapered surface, and the ball 12 moves outward from the radial direction to a predetermined position. To the side, where it comes into contact with the tapered surface 32a.

In this case, when the inclination angle of the tapered conical portion 16e becomes small, the wedge effect by the tapered conical portion 16e becomes large.

Therefore, the outer assembly 3 is forced by the pressure applied from the ball 12 to the tapered surface 32a of the ball retainer 32, so that the outer assembly 3 is connected to the upper surface of the outer assembly 3. Move the end of the face until it comes in contact with the end of the mating face below the inner assembly (2).

In this way, even if there is a gap between the two assemblies due to irregular operation, the tapered surface of the ball rotating body 16c is reliably pressed outward from the radial direction so that the external assembly is moved upward, thereby suppressing such irregular operation. do.

As a result, in the absence of a gap between the two assemblies, the two assemblies are always in a fixed state, that is, malfunctions in the fixed position are improved, and recurrence of the connectors 23 and 35 is further improved. Contact is also improved.

In general, compressed air always acts on the piston 16, but even if the supply of compressed air to the upper surface of the piston is interrupted, the ball is moved inward from the radial direction by the weight of the external assembly 3 containing the tool, 16 is raised, whereby the cylindrical surface (cylindrical portion 16f of small diameter) is connected to the lower side of the first tapered surface (tapered conical portion 16e), at which point by the ball 12 The lifting force of the piston 16 becomes useless and the fixing of the two assemblies is prevented from loosening itself.

In this case, when the two assemblies are loosened, compressed air is supplied to the lower side of the piston main body 16a through an air hole (not shown) formed in the master body 11 to raise the piston. Thus, the ball 12 moves inward from the radial direction, and both assemblies are disconnected. At this time, the area which can be subjected to a large pressure while the small diameter shaft 16b is connected to the lower part of the piston main body 16a of the large diameter is the piston when the piston 16 rises from the lower part of the piston main body 16a. Compressed air capable of operating (16) can be obtained, and it can rise with a greater force than when lowering the raised piston.

The present invention can be carried out in various forms without changing the main function, the above embodiment has been shown one example for the purpose of illustration, but is not limited.

Furthermore, the scope of the present invention is not limited to the above-described claims, and changes under the conditions of the claims and equivalent to those conditions are included in the claims.

Claims (5)

An internal assembly (2) connected to the robot arm, an external assembly (3) to which a tool or other tool is attached, a fastening device for holding two electrical assemblies, including an electrical fastener, an internal assembly between the fixed and released positions By a piston member 16 smoothly supported by a plurality of balls, a plurality of ball members 12 supported by an inner assembly 2 around the piston member 16, a ball retainer 32 attached to the outer assembly, and the like. In the robot arm connecting device, when the piston member 16 is moved to the fixed position, the robot arm connecting device can contact the tapered surface with the ball member 12, thereby supporting the two assemblies in a coupled state. And the contact surface of the piston portion (16) together with the ball member (12) is at least part of the first tapered surface. 2. The robot arm connecting device according to claim 1, wherein a contact surface between the piston member (16) having a cylindrical surface and the ball member (12) is connected below the first tapered surface. 3. The cylindrical surface of the piston member 16 is connected to the second tapered surface from below, and the taper angle of the first tapered surface with respect to the vertical axis is made smaller than the taper angle of the second tapered surface with respect to the vertical axis. Robot arm connection device characterized in that. The robot arm connecting device according to claim 3, wherein the taper angle of the first tapered surface with respect to the vertical axis is about 15 degrees, and the taper angle of the second tapered surface with respect to the vertical axis is about 30 degrees. The small part according to claim 1 or 2, wherein the first part of the large diameter and the surface in contact with the ball member 12 are inclined, the second part having a tapered surface, and the small part connecting the first part and the second part. Robot arm connecting device characterized in that the piston member (16) consisting of a third part of the aperture.