GB2025281A - Triaxial Programmable Module for Machine Tool Control Elements - Google Patents

Abstract

A triaxial programmable module, for machine tool control elements, includes, parallel to each of the axes X, Y, Z of a cartesian coordinates system, at least one guide 2 e.g. a hole or groove, which crosses spacially, all other perpendicular guides without intersecting them, as well as a number of kinematics programming devices acting over the movements of one or more guides. <IMAGE>

Description

SPECIFICATION Triaxial Programmable Module, Appliable to the Assembly and Testing of Machine Tools and their Control Elements Between the actual biggest problems in mechanical engineering is the fault of a modular element for interconnecting the mobil machine elements, being also able to solve in a fast, accurate, powerfull, easy and economic way, the different types of movements and stresses in a mechanical system.

This fact can be justified due to the extreme systems complexity. For example, in the relative motion between two bodies, can appear 64 variations, as a result of considering, by means of the Boolean laws, the existence or not of freedom in each of the six parameters which define the gravity center speed and the rotation of mobile body related to the fixed one. Not considering from the former variations those obtained by circular permutation, the independent allowed possibilities for the mobile body decreases to 20.

For example, a cylindrical friction bearing solves the case of motion of an axle across him with only two allowed parameters: the rotation around the cylinder axis and the translation in the axis direction. No other freedom or parameter is allowed. As a further example, an inside threaded socket allows a screwed rod to move inside him rotating and translating at the same time. This case, however, differs from the former one by the existence of a relation between both apparent parameters conditioned to the thread. In other words, between the 20 apparent mentioned possibilities, many others with great practical interest are not included. For example, a thrust bearing can have different forms depending on the fact that external forces are acting in one or both senses, and also if torques appear.The former 64 mentioned variations must be combined with another 64 becoming from the consideration as per the Boole algebra of existence or not of three possible force components and three torque components. Here are not still included the combinations submitted to special relations.

The machine tool work movements must be accurate, allowing only small deviations when applying big work stresses, which calls for a high strength. Current machine tools are built including a bed in which the necessary mobile elements are supported and having a complex casting or welded building method, with a difficult design and long manufacturing time due to the necessity of using specials techniques and machines. All this contributes to a high final cost. Another problem with those machines is their difficult transport and its unability to be reconverted if required. As there is a big number of machine tool makers, to the former we must add the great variety of different parts and spares, which unables their normalization.

Another type of workshop machinery is formed, for instance, by coordinate measuring machines, destined to measure the workpiece dimensions. They have a main inconvenient: although there are not working stresses, it is usual to put the heavy workpieces over the machine, which calls for a high strength. Due to that, they have a not economical price for small companies.

Robots and manipulators are among the more complex motion systems, including a high number of freedom degrees. Their actual cost is also very high on despite of the fact of the use of low cost microprocessors. A consideration of existing system reveals that their mechanical comnjexitv derivates from the use of a great variety of different elements with high manufacturing costs.

It is already known a two axis modular block, used on machine tools which have slide guides in two directions X, Y allowing only linear displacements, with only one fixed freedom degree. The rest of motion types as rotations, helicoidal movement, independent rotation and translation, total blocking, etc., are not attainable.

Any motion guidance possibility, perpendicular to the XY plane is not allowed.

Another known solution used in optics has neither possibility for programming the guides movement, having only translation freedom degrees.

This inventive idea deals with a module which eliminates the former inconvenients at the time that offers new advantages. For the building of the mentioned machine tools and systems, the present module, combined with unidimensional elements as rods, shapes, etc., as well as twodimensional, like sheets and thick plates, or tridimensional ones, like compact blocks, should solve any kind of structural problem, as, for example, paralelizing, perpendicularity, crossing, line and plane intersecting, rotation, translation, positioning and directioning of solids at any space point. It can originate movements following cartesian, cylindrical or spherical coordinates. A single type of module can be used for connecting one-, two- or tridimensioned elements as mentioned.This module, as well as their auxiliary elements can be prefabricated and standarized, allowing the direct building of machine tools without making any new holes. Each desired movement programming between a guide and the elements attached to it should be made in an easy way without requiring unusual pieces. It should be also able of processing other energy types than the mechanical, like hydraulic, pneumatic or even electrical. Been accurately built, it allows a machine tool assembling without additional stresses. The module should allow low weight building, and easy dissassembling and disposal of fixed and mobile systems. Its cost should be low, maintaining the strength of existing structures.

Another modules and auxiliary elements should be attachable or added, in order to strength the original structure if necessary, and easy to handle and useful for teaching of mechanical machine theory, as well as a good help in quick testing of new systems, specially automatic control ones, been also appliable to the simulation of systems with help of electronic equipment, mainly using microprocessors. It can solve also the support of auxiliary parts as sensors, longitudinal measuring slides or simple covering elements as sheets. It also allows the connection with screwed rods, ball or roller bearings and other parts. Machine tools made with would be lightly, easy to transport and to assemble even near another fixed machine tools in order to make measurements without moving the measured workpiece out of the work machine.

The solution hier claimed consist in a module which can have diverse shapes, for example cubic, paralelepipedic, cyclindrical, spherical, etc., compact or hollowed inside, with some guides, each having one or more kynematics programming devices, which allows to the elements inside them to move as per different types of movements.

That guides can be holes or grooves, in different shaped and sizes crossing over all the module length on each X, Y, Z direction. They can be smooth or threaded in the whole or in a part of their length, and can have also diverse circular grooves. Equally, small channels can be disposed permitting to create an hydraulic or pneumatic supporting pressure or a better lubrication. Those guides in one module can be different. Any case will be allowed to show interference between them, although, as a limit, they can be tangential.

The number of guides on each direction X, Y, Z can be also different, and the planes defined by each couple of paralel guide axis, if any, can be oriented in different directions. If they are equal, for instance one, which allows a bigger guide section, or two, allowing a whole symmetrical module version if desired. In a practical form, external plain surfaces can be achieved so enabling the broad contact with other plain surfaces, or the covering of a formed structure by means of plates or plane pieces, which also can improve the strength in the correspondent direction. Another form can have cylindrical surface, then enabling its use as an hydraulic piston. Another version can have, paralel to one axis, specially if the surface has plane sides, longitudinal protruding profiles, allowing the module assembling to a surface with correspondent grooves.

it is understood as a kinematics programming device in this invention, any system which allows to modify or program the selected relative motion or even to block the element inside the guide in relation to the guide itself by means of auxiliary pieces having physical contact with said element.

The relative movements or freedom degrees can be: pure rotation, pure translation, independent translation and rotation, helicoidal movement, etc. With this kinematics programming device, the obtained bindings can support diverse forces or torques, for example, forces in one or two senses, axial clearance control forces, radial clearance control, etc. This kinematics programming can be obtained by means of programming holes or grooves, oriented perpendicularly to the correspondent guide and having diverse shapes and sizes, crossing over or not, smooth or threaded in the whole or in a part of their length, and can have also diverse circular grooves. Their number can be one or more for each guide.The intersection between two programming holes or grooves is a possibility which do not disturb their function, although in this case, the auxiliary programming elements used for each guide could not be retired across one end of the connecting hole as it appears by using a not crossing over hole.

The auxiliary programming elements housed in the correspondent programming holes or grooves can be different, for example, pins, threaded rods, screws, clips, etc. We can have also some auxiliary elements inside the guides, for instance, inside threaded sockets, ball or roll bearings, shielded and rings, fastening rings, cams, plugs, grooved rods, etc.

The module can be made with different materials, been of special interest the use of electrical isolating ones, which allows to make different electrical circuits, combining the programming holes and different guides.

In drawings which illustrate embodiments of the invention, Fig. 1 is a sample of module with two guides and four programming holes on each direction.

Fig. 2 is a detailed A-A section of module in Fig. 1, including hydraulic or pneumatic support elements both on the guides and external surfaces.

Fig. 3 is a module sample with groove type guides and programming holes.

Fig. 4 is a partial view of a practical possibility for programming holes acting on the guides.

Fig. 5 is a sample of auxiliar kinematics programming elements.

Fig. 6 shows a hydraulic programming method sample by means of a grooved cylindrical rod.

Fig. 7 is a B-B partial section of Fig. 3 module, showing the hydraulic or pneumatic support forces.

Fig. 8 is a machine tool structure sample built by means of a cubic type of module.

Fig. 1 shows a cubic version 1 with same number of guides 2 on each direction, as well as four kinematics programming holes 3. Section A-A belonging to a version iS seen on Fig. 2.

Guides 7, 9, 2, 8 here shown have hydraulic or pneumatic support channels 5 connected to its programming hole 4. The guides have a smooth and a threaded part 9a. On the module sides 10, cavities 1 0a have been made, giving hydraulic or pneumatic support over a plain external surface 26 in a similar way to the showed in Fig. 7. In Fig.

3, another cubic version 11 of this module appears, similar to the former 1, with grooves having a cutted circular shape 22. The programming holes 23, have a complete circular sectioncrossing over the module, showing this figure their relative independence in the crossings with another ones 24. Section B-B on Fig. 7 shows a simplified variety 32 of module 1 which can performs equally the desired function giving a sample of cutting between programming holes 30a and the correspondent guide. Various programming solutions appear on Fig. 5. Here is showed, for example, how to block a tube 12 inside the guide 6 by means of a pin 14 inserted throw the hole 12a. If a pure rotationmovement for the rod 15, having a groove 16, is desired, can be achieved by inserting throw the hole 12a a pin 18 whose loosening ist avoided by threaded bolt 19.Rod 1 5 would become blocked if it is strongly tightened by pin 18 across the threaded bolt 19.

Those last two pieces can also be used allowing a single type of movement of rod 20 or its complete blocking. For the hydraulic or pneumatic energy control, is also possible to use this module advantages. So the version 1 has six independent circuits each one having two exits or guide ends 30. Fig. 6 shows schematically a way of controlling a fluid flow 35 feeded at a pressure 34 across an inlet 30a, been the outlet flow 35 across the hole 31 a depending upon the rotation 36 or translation 37 of the control grooved rod 33. In Fig. 7 appears the flexibility of this module in achieving pneumatic support 28 equalized by pressure 29 due to the flow 27 and 27a when passing across hole 24, being the module 11 placed on a plane surface 26 having a protruding profile 25. This can be also achieved by module 1, inside its guide 9 or in the surface 10. Fig. 8 shows a sample of a boring machine structure arrangement, in which module 39 can support the tool having three displacement freedom degrees 50 as per X, Y, Z, made of nine modules 39, all which can be identical but individually programmed with necessary guides for housing diverse tubes 43, 44, 45, screwed rods 41 and engines 47, 51, 52 being each couple of screwed rods 41, 41a, for instance, chain synchronzed.

Most diverse machine types can so be achieved or simulated.

Claims (10)

Claims

1. Triaxial programmable module, appliable to the assembly and testing of machine tools and their control elements, as well as another power systems based on mechanical, hydraulic, pneumatic or electrical energy, which enables fixed structures assembly, practically made in a variable stiff shape, distinguished by having, paralel to each of the axis X, Y, Z of a cartesian coordinates system, at least one piercing guide, which cross spacialy other perpendicular guides without intersect them, as well as a variable number of kinematics programming devices acting over the movements of one or more guides.

2. Module as per former claim, in which the kinematics programming is made by means of a variable number of programming holes or grooves which intersect at least one guide following a direction contained in one plane perpendicular to the guide axis.

3. Module as per one of the former claims, in which the number of guides in all directions X, Y, Z are equal.

4. Module as per one of the former claims, in which the minimum distance segments between perpendicular guides are symmetrical in respect to a line crossing the module.

5. Module as per one of the former claims, in which all the guides have the same section.

6. Module as per one of the claims 2 to 5, in which the programming holes or grooves intersect each only one guide.

7. Module as per one of the former claims, in which there are external plane surfaces perpendicular to the guides.

8. Module as per one of the former claims, in which there are hydraulic or pneumatic support devices.

9. Module as per one of the former claims, made with electrical isolating material.

10. Module as per one of the former claims, in which protruding profiles paralel to one or more guides outside of the main geometrical module shape.