EXPANDABLE FINGER GRIPPER

Abstract

The invention concerns a pneumatically controlled finger gripper that comprises a supporting body (11) with a proximal and a distal end, a pneumatic control piston (12) guided and moving alternatively in said body, a compression disk (13) connected to, and moving axially with, said piston relatively at the distal end of said supporting body, and a flexible gripper element (14) assembled between said compression disk (13) and said distal end of the supporting body (11) and moving between a contracted and expanded position in response to the movements of the control piston with the compression disk between an inactive and active position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Further details of the invention will become more evident from the following description made in reference to the enclosed indicative and not binding drawings, in which:

FIG. 1 shows a blow-up of a function mode of the finger gripper according to the invention;

FIGS. 2 and 3 show an external view of the assembled tool with the gripper element in the contracted and expanded position respectively;

FIGS. 4 and 5 show a longitudinal section of the tool with the gripper element in the contracted and expanded position respectively;

FIG. 6 shows a variation in construction of the tool, in which the command fluid is fed through an axial conduit in the piston;

FIGS. 7 and 8 show a longitudinal section of the tool with the gripper element in the contracted and expanded position respectively, equipped with a end of stroke stop and a modified compression disk;

FIGS. 9 and 10 show, respectively, and external view and an enlarged longitudinal section of the tool equipped with position sensors; and

FIG. 11 shows the section of a tool corresponding to the one in FIG. 6 but equipped with a through axial conduit for it use in pressurising or creating a vacuum in a cavity.

Claims

1. Pneumatically controlled finger gripper, characterized by a supporting body having a proximal end and a distal end, a pneumatically controlled piston guided and moving alternatively in said body, a compression disk connected to, and moving axially together with said piston relatively with the distal end of said supporting body, and a flexible gripper element assembled between said compression disk and said distal end of the supporting body and moving between a contracted and an expanded position in response to the movements of the piston with the compression disk between an inactive and an active position.

2. Finger gripper according to claim 1, in which the supporting body forms a chamber closed by a plug at the proximal end and with an end bore at the distal part of said body, in which the control piston is housed and moves and has at least one rod that extends into said end bore and connects with the compression disk, and in which the flexible gripper element is placed around the connecting zone of the compression disk with the control piston rod, between said compression disk and said supporting body, said chamber being fed by a fluid under pressure to move the piston from the inactive position in which the gripper element is contracted and the active position when the gripper element is expanded.

3. Finger gripper according to claim 1, in which the flexible element is basically tubular in shape, made of rubber, silicon or the like and has a convex wall acting as a receptacle for its expansion only towards the external.

4. Finger gripper according to claim 3, in which the flexible gripper element has either a continuous and uniform or shaped or corrugated external surface.

5. Finger gripper according to claim 1, in which said chamber is fed by a fluid under pressure for the movement of the control piston from said inactive to said active position, the inactive position usually being maintained by the flexible gripper element and/or a return spring positioned between the piston and the proximal plug.

6. Finger gripper according to claim 5, in which the supporting body has a radial bore to feed the fluid under pressure into said chamber to move the control piston from the inactive to the active position.

7. Finger gripper according to claim 5, in which the control piston has a longitudinal conduit with an inlet facing towards the proximal plug and an outlet on a level with the piston rod to feed the fluid under pressure into said chamber to move the control piston from the inactive to the active position.

8. Finger gripper according to claim 1, in which in the proximal plug, in the piston and relative rod and in the compression disk a through passage has been provided which can be connected to and air under pressure feed pipe or a suction pipe to use the finger gripper to pressurize or respectively create a vacuum in a container.

9. Finger gripper according to claim 1, in which a means to detect and limit the control piston stroke from the inactive to the active position is inserted in the supporting body to control the expansion of the gripper element.

10. Finger gripper according to claim 9, in which said means is made up of a mechanical stop device applied to the proximal plug of the supporting body to intercept the control piston stroke.

11. Finger gripper according to claim 9, in which said means is made up of at least one electronic presence sensor fitted to the supporting body and interacting with a magnetic element fitted directly or indirectly to the control piston.

12. Finger gripper according to claim 1, in which the proximal part of the supporting body or the proximal plug has a connection or joint for connecting to a manipulator.

13. Finger gripper according to claim 1, in which the compression disk is flat or convex.