RU2743441C1 - Manipulator gripper with electrically conducting flexible carbon material working element - Google Patents

Abstract

FIELD: robotics.

SUBSTANCE: invention relates to robotics and can be used in gripping devices of manipulators. Gripping device comprises housing with working contact pad filled with working medium. Contact pad is made in the form of one of container sides and has inclined cuts. Working element is made in form of strips of electroconductive flexible carbon material passed through inclined slots and fixed with possibility of supply of electric voltage to them in attachment points. Fastening points are arranged on contact pad outer and inner sides. Elastic heat-resistant elastic pad cushions are arranged on body container under strips of electroconductive flexible carbon material. Strips are made with possibility of their wetting with working medium and transportation of working medium to place of contact with gripped object. Heating element is arranged in vessel container.

EFFECT: as a result, it is possible to grip objects of different shape and dimensions.

6 cl, 1 dwg

Description

The invention relates to robotics, in particular to the field of equipping robotic manipulators with gripping devices.

The device can be used as a universal gripping head of the manipulator, capable of providing the ability to grip various objects and / or reliable grip with them, which can find its application in the production of robots capable of handling objects that have both large dimensions and non-standard geometric shapes manufactured from magnetic and non-magnetic materials, as well as in the production of mobile devices capable of moving in difficult conditions, including on vertical surfaces and surfaces with a negative angle of inclination.

In known devices for gripping objects with manipulators or for gripping with them, gripping heads with finger organs are used [1 RF Patent No. 2381892 from 20.02.2010], vacuum [2 RF Patent No. 2397857 dated 27.08.2010] or magnetic [3 Patent RU No. 2016757 from 07/30/1994] holders. The disadvantage of these devices is the limited scope of their application. The use of devices with finger organs is limited by the overall dimensions and geometric shape of the objects to be captured, devices with vacuum holders - by the geometric shape of objects and the quality of their surface treatment, devices with magnetic holders - by the magnetic properties of the material of the objects.

Several types of gripping head designs are known, in which the effect of surface tension of condensate specially created on the working surface of the gripping head and the effect of freezing of the object to the gripping head when it cools is used to ensure adhesion to objects. So, the device "Capillary microcapture with feedback" [4 RF Patent No. 2261795 dated 10.10.2005] contains a base, a fastening device. The base is made of an electrically insulating material with high thermal conductivity, on which moisture capacitors are installed from the working surface in a grid pattern, made in the form of thermoelectric modules based on the Peltier effect. Electrically conductive plates are placed between the moisture capacitors in a lattice arrangement. Electrodes are installed along the base contour. The principle of operation of the device is based on the effects of surface tension (capillary forces), when a liquid between two surfaces creates an adhesive force, leading to adhesion of the surfaces. The nature of these forces is determined by intermolecular interactions and the structure of the surface layer. Condensate, which forms on the surface of moisture condensers, is used as a liquid that creates adhesion force.

The disadvantage of this micro-gripper is the limited use of the device associated with the small overall dimensions and low weight of the captured objects.

As a prototype of the present invention, the "Robot gripping device" is used [5 RF Patent No. 2320475 from 03/27/2008]. This device uses a plastic spongy substance impregnated with a working fluid to provide grip. The gripper is directly fixed when the working fluid is cooled until it solidifies, while the gripping object freezes to the plastic spongy substance. The gripping device of the robot manipulator is equipped with a thermoelectric battery (TEB) supplied with a constant electric current and a container filled with an easily evaporating coolant. The first thermopile junctions are in thermal and mechanical contact with the surface of the fastening mechanism, and the second junctions are in contact with one of the surfaces of the said container, on the opposite surface of which a plastic spongy substance is applied. Moreover, the thermopile operates in the cooling mode when gripping, moving and positioning the object and in the heating mode when removing the gripping object, and the manipulator and the fastening mechanism are made with channels for pumping coolant through them. The inner surface of the container can be made with ribbing.

The disadvantages of this device are the increased consumption of the working fluid, the delivery of which to the place of use is not provided, the need for periodic refueling with an easily evaporating coolant, the increased consumption of electricity used for constantly alternating processes of heating and cooling the coolant, the low adhesion strength with the object of capture compared to the proposed device

The proposed invention allows you to overcome the above limitations and disadvantages and create universal gripping devices that can work with different types of objects, including large-sized objects and small objects, with objects with a complex geometric shape, with a porous or rough surface, with objects manufactured from non-magnetic materials. At the same time, there is no need to replace the gripping head every time the type of object to be gripped is changed, which increases the productivity of the robot and expands the scope of its possible application.

In the proposed technical solution, to ensure the reliability of the grip and the strength of adhesion to the gripped object, a substance can be used as a working medium, which under normal conditions is in a solid state in the form of granules, powder or other crushed form, placed in the body container of the gripper, while the working element that comes into direct mechanical contact with the gripped object is an electrically conductive flexible carbon material, which is both a heating element for melting the adhesive and a transport element for delivering the working medium to the place of contact with the gripped object. At low temperatures (below 10 ° C), distilled water can be used as a working medium. After fixing the gripping object for its further retention, additional energy consumption is not required. In conditions of exclusion of traces of adhesive on the object, rapidly evaporating substances, such as naphthalene, are used as the working medium. Under conditions of thermal bonding, hot melt glue can be used as a working medium, which has increased adhesion, which helps to increase the reliability of adhesion of the object to the working surface of the gripping head of the manipulator. In the proposed technical solution, hot melt adhesive is a consumable material, which in its original state is granules or powder. Heating of an electrically conductive flexible carbon material having the shape of a strip of the required and sufficient length and width is carried out by applying an electric voltage to the ends of the strip through the contact pads. The hot melt adhesive is delivered to the point of contact with the object due to gravity and the effect of wetting the electrically conductive flexible carbon material with hot melt adhesive. Thus, unlike the prototype and other similar devices, the proposed device has a simpler design, since there are no additional mechanisms for supplying the working medium (pumps, feeders, extruders, any moving parts and mechanisms), as well as thermoelectric batteries in the gripping head. , and for melting and transporting the working medium, stationary strips of electrically conductive flexible carbon material are used, wetted by this working medium. To increase the speed of the device, an additional electric heating element in the form of a metal plate or a spiral can be used, placed in a container with a working medium: granules, powder or solid substance in another crushed form.

The design of the "Gripping device of the manipulator with a working element made of an electrically conductive flexible carbon material" is shown in the drawing (Figure 1, side view and front view).

1 - strips of electrically conductive flexible carbon material; 2 - heating element; 3 - the upper contact area and the place of attachment of the strips of carbon fabric; 4 - working environment; 5 - body capacity of the capture; 6 - manipulator lever; 7 - the lower contact area and the place of fastening the strips of electrically conductive flexible carbon material; 8 - elastic heat-resistant pad; 9 - inclined slots in the front wall of the gripper; 10 - the front wall of the gripper body container.

The front view of the gripper shows the front (working) side of the gripper, i.e. the side of it that sticks or freezes to the captured object.

The body capacitance of the gripper is made of a heat-resistant dielectric with a low thermal conductivity coefficient. The thermal resistance of the material of the vessel container depends on the melting temperature of the working medium. Provided that various brands of hot melt glue are used as a working medium, the material of the container is made of a heat-resistant material corresponding to the melting temperature of the hot glue (from 150-170 ° C and above). The most suitable materials are fluoroplastics of various brands, fiberglass, heat-resistant plastics and composites. Provided that distilled water is used as a working medium for adhesion, in the case of low operating temperatures, there is no requirement for heat resistance to the material of the vessel container.

The pads on the working (front) side of the gripper can be made in the form of elastic pads made of an elastic heat-resistant material, for example, heat-resistant rubber or silicone. Structurally, the pads are placed under strips of electrically conductive flexible carbon material and adjoin directly to the face plate of the gripper body container, to which they are rigidly attached (for example, using an adhesive bond). The presence of pads capable of elastically deforming when the gripper is pressed against the gripped object increases the area of mechanical contact of the strips surface with the object surface, which ensures greater reliability and strength of the grip.

The gripper structure is based on strips of electrically conductive flexible carbon material. At the same time, the design of the gripper allows the use of a very different number of strips. The dimensions of the strips can be very different, for example: 10 × 100 mm, 15 × 100 mm, 50 × 200 mm, etc. The shape of the stripes is predominantly square or rectangular. The drawing shows a variant of the gripper with three stripes. Each strip of electrically conductive flexible carbon material is passed through an inclined slot made in the plate, one side of which is the working side of the gripper, and the other is the inner wall of the body container with the working fluid, while one end of each strip is in the body container with the working fluid, and the other end is on the working side of the gripper. As the electrically conductive flexible carbon material, carbon tapes, fabrics, carbon felt, needle-punched carbon nonwoven fabric can be used.

The proposed capture works as follows.

1. Provided that hot melt glue is used as a working medium, when an electrically conductive flexible carbon material 1 is applied to the strips through contact pads 3 and 7 of an electric voltage, the strips are heated and that part of the hot melt glue that is located both in the channel of each inclined slot 9 and on the outside of the strips. Depending on the melting point and heat capacity of the hot melt glue (or other working fluid) to accelerate its melting in the container 4 and increase the speed of the device, the voltage can also be applied to the additional electric heating element 2. Due to the force of gravity and the effect of wetting the electrically conductive flexible carbon material, the liquid hot glue gradually enters along the stripes and accumulates on the part of them that is located on top of the overlays 8. After the accumulation of a sufficient portion of glue, the manipulator with the help of the lever 6 presses the working surface of the gripper to the object. After switching off the current, the adhesive cools and hardens, thereby providing the necessary adhesion. Elastic pads, over which the protruding parts of the strips of electrically conductive flexible carbon material are fixed, contribute to an increase in the contact area between the object and the grip, and the high mechanical strength of the electrically conductive flexible carbon material ensures the strength and reliability of the grip itself. To release the grip, the strips of electrically conductive flexible carbon material are heated, for which they are again energized, a thin layer of hot melt glue located between the protruding parts of the strips and the surface of the gripped object melts, the adhesion between it and the grip weakens, which leads to the release of the gripped object ...

2. Provided that distilled water is used as a working medium, the device can be prepared for operation at an ambient temperature above the freezing point of water, for example, at room temperature. Distilled water is poured into the capture tank. At low operating temperatures, water freezes on the working surface of the gripper, which ensures the freezing of the gripper to the object. The rest of the operation of the gripper is similar to item 1.

3. Provided that rapidly evaporating substances are used as a working medium, the operating procedure of the gripper is also similar to clause 1, while in order to ensure the subsequent absence of traces of adhesive on the captured object (for example, to preserve the presentation of the object), a substance is used as the working medium, which evaporates rapidly while in the solid phase, and the room in which the work is carried out has a ventilation system sufficient to capture and / or remove the fumes.

Findings.

The technical result of the invention is the versatility of the device in comparison with the existing counterparts, the simplicity of the device design, which makes it possible to manufacture a class of manipulators for robots with a higher productivity, while less energy-consuming.

Sources of information

1. RF patent No. 2381892, IPC B25J 15/08, he. 02/20/2010, З..№2008120424 from 05/22/2008,

2. RF patent No. 2397857, IPC B25J 15/06, he. August 27, 2010, Z. No. 2008126662 dated June 30, 2008,

3. Patent RU No. 2016757, IPC B25J 15/06, op.30.07.1994, Z. No. 4812228 dated 09.04.1990.

4. RF patent No. 2261795, IPC B25J 15/00, op.10.10.2005, Z. No. 2004105379 dated 24.02.2004,

5. RF patent No. 2320475, IPC B25J 15/00, op. 23.07.2008, Z. No. 2005137510 dated 01.12.2005,

Claims (6)

1. The gripping device of the manipulator containing a body container with a working contact area filled with a working medium, a working element, a heating element and a lever, characterized in that the working contact area is made in the form of one of the sides of the body container and has inclined slots, and the working element is made in the form of strips of electrically conductive flexible carbon material, passed through inclined slots and fixed with the possibility of supplying electric voltage to them at the attachment points located on the outer and inner sides of the working contact pad, and pads in the form of elastic pads made of elastic heat-resistant material, placed on the body container under the said strips of electrically conductive flexible carbon material, the latter being made with the possibility of wetting them with the working medium and transporting the working medium to the place of contact with the captured object, and the heating element is located in the body container. 2. The gripping device according to claim 1, characterized in that the body container is made of a heat-resistant dielectric material. 3. The gripping device according to claim 1 or 2, characterized in that an electrically conductive flexible carbon material is used in the form of a tape, or felt, or a needle-punched nonwoven material. 4. Gripping device according to any one of paragraphs. 1-3, characterized in that distilled water is used as the working medium. 5. The gripping device according to any one of paragraphs. 1-3, characterized in that a thermosetting adhesive is used as the working medium, which is in a solid state in the form of granules or powder and turns into a liquid state at the melting temperature. 6. The gripping device according to any one of paragraphs. 1-3, characterized in that a rapidly evaporating substance is used as the working medium.

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