DESC:THREE DIMENSIONAL COORDINATE MEASURING MACHINE

Field of invention:

The present invention relates to Coordinate Measuring Machine (CMM) and in particular relates to three dimensional coordinate measuring machines for shop floor application.

Background of the invention:

A coordinate measuring machine (CMM) is a device for measuring the physical geometrical characteristics of an object. This machine is controlled by controller and user has to operate through software loaded on the computer.

Figure 1 shows an existing coordinate measuring machine (CMM) (100) employing three main components a first component (110), a second component (120) and a third component (130) moving along guideways perpendicular to one another to provide three axes of motion. The probing system is attached to the first component (110) which is carried on and moves vertically in relation to the second component (120). The combined assembly of the first (110) and second components (120) moves horizontally relative to the third component (130). The third component (130) is supported at one end only in a cantilever fashion and moves horizontally relative to the machine base (140), on which the work piece is supported.

The drawbacks in existing coordinate measuring machine (100) are that:
a) The work piece resting on the workbench (150) is a fix table that has no provision of movement in vertically up and down direction.
b) Comparatively less distance between the guide rails for mounting third- component (130)/cantilever axis on machine base (140).
c) Asymmetric construction of cantilever axis to carry second component (120) on which first component (110) or Z-Axis moves, This asymmetric design also have non uniform behavior and slow response to the temperature change.

Therefore, there exists a need to provide a simple and improved coordinate measuring machine (CMM) design which would be an alternate to above options and overcome defects in existing design.

Objects of the invention:

An object of the present invention is to provide a coordinate measuring machine (CMM) having a workbench with Up-Down mechanism of 200mm which allows additional space for large component resting, rotary table mounting and allowing using motorized Indexing probing system with longer extensions.

Another object of the present invention is to provide the CMM machine that allows maximum center distance in LM (Linear Motion) guides helps to minimize the angular errors of axis.

One another object of the present invention is to provide symmetric construction of cantilever axis that allows uniform thermal behavior and also allows moving Z-Axis centrally.

Further object of the present invention is to provide structural components of CMM to be made up of special grade of Aluminum to have uniform behavior and fast response to the temperature behavior.

Summary of the invention:

Accordingly, in one aspect, the present invention provides a three dimensional coordinate measuring machine for metrology lab and shop floor application. The coordinate measuring machine has a main structure with a probe that can be moved with three axis of motion the X- axis, Y axis and Z axis. All three moving axis are connected to a machine base. The base also does the function of part/component loading on work piece resting bed/pallet that can slide in upward and downward direction. An X carriage is connected to the machine base through two guide rails one on the top and second on the bottom side. The X carriage is designed in specific L shape which holds traverse axis i.e. the Y axis. Vertically moving Z axis is inside an enclosure, wherein guide rails for Z axis are assembled in enclosure. The machine construction includes the machine base with arrangement for holding work piece on work piece resting bed, characterized in that, the work piece resting bed is constructed such that the bed can be adjusted and moved in vertical direction with help of up-down mechanism. The machine base is also connected with wall-member on which two guide rails are mounted. One of the guide rails in vertically upward and second guide rail in horizontal in the bottom area of the wall member, on these guide rails the carriage travels along the X axis.

The symmetric design of X carriage provides mounting arrangement for Y axis guide rails. The tool magazine is mounted on X carriage which allows for shorter changeover tool changing times while measurement. The section of the X carriage has been designed to allow visibility of the piece to be measured, which is unknown to machines with classical geometry. The Z carriage provides guide rails for Z axis to travel in vertically up and down direction. Z carriage travels on the Y axis perpendicular to X axis. Z carriage also holds pneumatic cylinder which gives counter balancing force to the Z axis extension called as spindle. Measurements are defined by a probe attached to the first moving component called as spindle. The continuous belt drive arrangement is made for Y and Z axis movement, where as positive drive system is used for X axis movement. A scale and optical encoder arrangement is made to read position of probe-stylus tip which touches to the component measurement surface. X, Y, Z three encoders are connected to relevant carriage. The drive system is a belt drive/ball screw/ rack and pinion. The counter balancing is done with a pneumatic cylinder/ with brake motor. The construction of present invention provides space from three directions to load and unload the component to be measured.

Brief description of the drawings:

The objects and advantages of the present invention will become apparent when the disclosure is read in conjunction with the following figures, wherein:

Figure 1 shows the coordinate measuring machine (CMM) in accordance with the prior art;

Figure 2 shows the detail view of coordinate measuring machine (CMM) with movable work bench and linear motion guide rails in accordance with the present invention; and

Figure 3 shows the left side and right side view of coordinate measuring machine (CMM) with linear motion guide rails in accordance with the present invention.

Detailed description of the invention:

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.

The present invention provides a coordinate measuring machine (CMM), wherein the workbench is provided with Up-Down mechanism of 200mm which allows additional space for large component resting, rotary table mounting and allowing using of motorized Indexing probing system with longer extensions. Large apart distance for the Linear Motion (LM) guide rails is mounted with large distance to increase the rigidity and improve the geometrical accuracy and stability of component measurement through the probes.

This present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures.

Referring to figures 2 and 3, a three dimensional coordinate measuring machine (herein after, the machine (200)) for metrology lab and shop floor application, in accordance with the present invention is shown. The coordinate measuring machine (200) having a main structure with a probe that can be moved with three axis of motion the X- axis (210), Y axis (220) and Z axis (230). All three moving axis are connected to a machine base (260). The machine base (260) also does the function of part/component loading on work piece resting bed/pallet (240) that can slide in upward and downward direction.

An X carriage (210C) is connected to machine base (260) through two guide rails one on the top and second on the bottom side which can be seen in both left hand (LH) and right hand(RH) side view as shown in Figure 3. The X carriage (210C) is designed in specific L shape which holds traverse axis i.e. Y axis (220). A vertically moving Z axis (230) is inside an enclosure, wherein guide rails for Z axis (230) are assembled in the enclosure.

Machine controller and computer screen arrangement is compact and is provided with hinge connections for its movement. The machine construction includes machine base (260) with arrangement for holding work piece on work piece resting bed (240). Characterized in that, the work piece resting bed (240) is constructed such that the bed (240) can be adjusted and moved in vertical direction with help of up-down mechanism. The machine base (260) is also connected with wall-member on which two guide rails are mounted. One of the guide rails in vertically upward and second guide rail in horizontal in the bottom area of the wall member, on these guide rails the carriage travels along the X axis (210).

The symmetric design of X carriage (210C) provides mounting arrangement for Y axis (220) guide rails. The tool magazine (270) is mounted on X carriage (210C) which allows for shorter changeover tool changing times while measurement. The section of the X carriage (210C) has been designed to allow visibility of the piece to be measured, which is unknown to machines with classical geometry. The Z carriage (230C) provides guide rails for Z axis (230) to travel in vertically up and down direction. Z carriage (230C) travels on the Y axis (220) perpendicular to X axis (210). Z carriage (230C) also holds pneumatic cylinder which gives counter balancing force to the Z axis (230) extension called as spindle (250). Measurements are defined by a probe attached to the first moving component called as spindle (250).

The continuous belt drive arrangement is made for Y (220) and Z axis (230) movement, where as positive drive system is used for X axis (210) movement. A scale and optical encoder arrangement is made to read position of probe-stylus tip which touches to the component measurement surface. X, Y, Z three encoders are connected to relevant carriage. The drive system is a belt drive/ball screw/rack and pinion. The counter balancing is done with a pneumatic cylinder/ with brake motor. The construction of present invention provides space from three directions to load and unload the component to be measured.

In an embodiment, the spindle (250) is made up of carbon fiber material. The machine base (260), X carriage (210C), Z carriage (230C) is made up of aluminum. The spindle (250) can be constructed with Aluminum/carbon Fiber material and combination thereof. The component mounting pallet or the work piece resting bed (230) can be Granite/ Granite plate with honeycomb structure. The machine base (260) is constructed of Aluminum/granite. The structural components are made up of special grade of Aluminum to have uniform behavior and fast response to the temperature changes.

The three dimensional coordinate measurement machine (200) for component measurement is useful on shop floor with metal processing machine like metal removal machines, metal forming machines etc. The present invention provides a robust design with symmetrical construction of the machine is suitable for harsh shop floor environment. Large apart distance for linear motor (LM) mounting to increase the rigidity, improves the geometrical accuracy and stability. Positive drive mechanisms are provided for high acceleration and smooth axis movement. Independent drive system frames are easy to assemble and maintain. Symmetric construction of cantilever axis allows uniform thermal behavior and also allows moving z-axis centrally. Workbench with up-down mechanism of 200mm stroke is useful when customer wants to use machine to accommodate components with measuring pallets and/or machine can be equipped with rotary table. Additional space availability in z direction allows using motorized indexing probing system with longer extensions. The machine is designed in such way that installation of machine will be faster as plug and play installation. Compact controller and user interface unit that is easily fold-able is provided. The machine design allows for easy relocation in shop or line for measurement. Integrated display is provided to show real-time temperature data of machine. The machine is also equipped with industry 4.0 for machine health parameters like machine running hours.

Advantages of the invention:

1. The present invention provides a robust design and symmetrical construction suitable for harsh shop floor environment.
2. The present invention provides a large apart distance for Linear Motion (LM) mounting to increase the rigidity, improves the geometrical accuracy and stability, maximum center distance in Linear motion guides helps to minimize the angular errors of axis.
3. The present invention provides a symmetric construction of cantilever axis allows uniform thermal behavior; also allow moving z-axis centrally.
4. The present invention provides workbench with up-down mechanism of 200mm stroke is useful to accommodate components with measuring pallets; machine can be equipped with rotary table; dimensional inspection of large components.
5. Additional space on work bench is allows using motorized indexing probing system with longer extensions.
6. The present invention provides plug and play installation, easy to relocate in shop or line for measurement.
7. The present invention provides an integrated display to show real-time temperature data of machine.
8. The present invention provides compact controller and user interface unit, easily fold-able.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the scope of the present invention.
,CLAIMS:We claim:

1. A three dimensional coordinate measuring machine (200) comprising:
a main structure with a probe that is moved with three axis of motion the X- axis (210), Y axis (220) and Z axis (230);
a machine base (260) connected to all three moving axes are (210, 220, 230), wherein the machine base (260) is also connected with a wall-member on which two guide rails are mounted, wherein one of the guide rails in vertically upward and second guide rail in horizontal in the bottom area of the wall member, and a carriage travels on the said guide rails along the X axis (210);
a work piece resting bed (240) arranged on the machine base (260) that is adjusted and moved in vertical direction with help of up-down mechanism,
an X carriage (210C) connected to machine base (260) through two guide rails one on the top and second on the bottom side, wherein the X carriage (210C) is designed in specific L shape which holds traverse axis that is the Y axis (220) and the vertically moving Z axis (230) is assembled inside an enclosure, wherein guide rails for the Z axis (230) are assembled in the enclosure, wherein a section of the X carriage (210C) has been designed to allow visibility of the piece to be measured;
a Z carriage (230C) arranged to provide guide rails for the Z axis (230) to travel in vertically up and down direction, wherein the Z carriage (230C) travels on the Y axis (220) perpendicular to the X axis (210);
wherein, construction of the machine (200) provides space from three directions to load and unload the component to be measured.

2. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein a tool magazine (270) is mounted on the X carriage (210C) that allows for shorter changeover tool changing times while measurement.

3. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein the Z carriage (230C) holds pneumatic cylinder which gives counter balancing force to the Z axis (230) extension called as a spindle (250), wherein measurements are defined by a probe attached to the spindle (250).

4. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein a continuous belt drive arrangement is arranged for movement the Y axis (220) and the Z axis (230) and a positive drive system is arranged for the movement of the X axis (210).

5. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein a scale and optical encoder arrangement is arranged to read position of probe-stylus tip which touches to the component measurement surface and X, Y, Z three encoders are connected to relevant carriage.

6. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein a drive system is a belt drive/ball screw /rack and pinion and a counter balancing is done with a pneumatic cylinder/ with brake motor.

7. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein the spindle (250) is made up of any material selected from aluminum and carbon fiber material and combination thereof.

8. The three dimensional coordinate measuring machine (200) as claimed in claim 1, wherein the machine base (260), the X carriage (210C), the Z carriage (230C) is made up of special grade of aluminum to have uniform behavior and fast response to the temperature changes.

Dated this 16th day of September 2020

Prafulla Wange
(Agent for applicant) (IN/PA-2058)