WO2014049379A1

WO2014049379A1 - Machine for manufacturing of custom-made foot orthotics

Info

Publication number: WO2014049379A1
Application number: PCT/HR2013/000026
Authority: WO
Inventors: Toma Udiljak; Karlo Obrovac
Original assignee: Toma Udiljak; Karlo Obrovac
Priority date: 2012-09-25
Filing date: 2013-09-24
Publication date: 2014-04-03
Also published as: HRP20120756A2; HRPK20120756B3

Abstract

The said invention refers to a fully automated CNC machine for manufacturing custom made foot orthotics according to the software- generated CNC (Computer Numerical Control) commands. The machine consists of workpiece carrier, with a device for the clamping and releasing of workpieces (3.12), which moves in the x-y plane during the machining cycle. The- individually controlled cutters (6.3) movable along the z-axis simultaneously machine either one workpiece (3.12) resulting with a pair of foot orthotics machined with the both sides, of two workpieces (3.12) resulting with two pairs of foot orthotics machined only on one side - in less than 6 minutes.

Description

MACHINE FOR MANUFACTURING OF CUSTOM-MADE FOOT ORTHOTICS

DESCRIPTION

Technical Field

The said invention refers to a CNC machine for the manufacture of custom-made foot orthotics according to the software-generated CNC commands. By its design, the said invention belongs to CNC milling machines with multiple cutters in a horizontal-milling setup, spatially arranged in collinear pairs which perform milling on a workpiece from the opposite sides. Here, all milling cutters are individually numerically controlled. By the type of machining, the invention belongs to CNC milling machines which work a 3D surface curved in two directions. By the surface treatment results, the said invention may be used for an effective manufacturing of foot orthotics, i.e. shoe inserts, in a narrower sense.

Technical problem

The said invention solves problems identified in the systems described hereby in the "state-of-the art" section.

The first technical problem that is solved by the said invention refers to the design of a CNC machine capable of forming a pair of foot orthotics machined on the both sides according to the previously determined tool paths generated by the software, without a further need for manual treatment of the workpiece in order to adapt the foot orthotics to shoes.

The second technical problem solved by the said invention refers to the ability of the machine to perform simultaneous machining of two pairs of foot orthotics in the way that each pair is machined only on the upper side of the insole, i.e. the side turned to the foot. Subsequently, this intermediate product is subjected to a further manual treatment to adapt the insole to the shoe. This solution does not require the modification of the machine in any of its segments.

The third technical problem solved by the said invention is that collinear pairs of cutters that perform machining (both the machining of one pair of foot orthotics on both sides and of two pairs simultaneously, but only on one side) balance the axial forces occurring during the treatment. That way this machine enables the machining of flexible materials thus making the minimum thickness of foot orthotics possible, which is a dream come true of end-users.

The fourth technical problem solved by the said invention refers to simpler removing and sucking of scrap material chips away from the workpiece since the cutters that machine the workpiece are in a horizontal setup.

The fifth technical problem solved by the said invention refers to the design of the machine which features automatic loading of blanks and automatic unloading , of the workpiece and the compact...design that can satisfy the needs of medical institutions.

The sixth technical problem solved by the said invention refers to the possibility to reduce the cycle time, both in the case of one pair of foot orthotics from the first technical problem and of two pairs of foot orthotics from the second technical problem, by up to 6 minutes.

State of the art

The state of the art is presented by the patent literature and several commercially available systems. Among them, one can find a number of CNC machines for the fabrication of prescription orthotics. The first one is ORTHEMA AUSTRALASIA (product - Orthema CNC Milling Machines) . The features .of the system are available at the following link: http : //www. orthema . com. au/orthema-products . aspx This machine, requiring the area of less than 1 square meter, equipped with a 3D foot contour digitizer, produces in situ orthotics in 10-15 minutes, with the declared accuracy of 0.1 mm. Although it is not explicitly pointed out, the declared accuracy in this case can be related only to the machining process according to a CAD model as there is no unique standardized gauge for determining the 3D accuracy. In addition, the considered system uses mechanical peg digitizing, a well-known procedure in the art. In the presented pegs matrix, a measurement error may occur along the very edge of the foot, where there are significant changes in the 3D curvature of the surface. This should be compensated by a denser matrix of pegs in order to ensure the declared accuracy of digitizing. A consequence of this error can be noted in the example presented on the manufacturer's website. The whole manufacturing process may be viewed at the Youtube® link: http: //www. youtube . com/watch?v=Y90N81QhEy8

Watching the film, one can notice that orthoses are machined one by one, and only on the upper side, that is the side turned to the foot. In the 9^th minute of the film it can be noted that intensive manual treatment of the orthotics bottom side is done to fit the shoe properly.

As opposed to the solution described above, the said invention fabricates foot orthotics which do not require additional machining. In addition, it features the automatic loading of blanks, which makes the CNC machine operator redundant. In the described example, the securing of the blanks to the fixture is done manually. In the process, care should be taken about the orientation with respect to the defined longitudinal axis. The securing of the blank to the fixture is done by means of adhesive tape, which means that additional material costs are involved. In addition, the handling of blanks, their securing, accuracy in positioning, productivity, system autonomy, and the very principle of machining are different from the proposed solution. Due to its technical solution, here disclosed invention is capable of machining the workpieces to become foot orthotics on both sides, i.e. on that turned to the foot and that turned to the shoe. This is not possible to achieve with the solution described on the above cited link.

Furthermore, at the Youtube® link: http : //www . youtube . com/watch?v=jXAoMOHxrDU one can find an effective and accurate DECLAM machine for fabricating foot orthotics. However, the machine does not feature the automatic securing of the workpiece and it is not automated; thus, it requires a constant assistance, see the 4th and the 5th minute of the film. Machining is performed on a table by means of one cutter, see the 6th minute of the film. It is quite obvious that here disclosed invention is better than the DECLAM machine in almost all aspects, particularly when the production rate, and autonomy are concerned.

At the link: http : //www . londonorthotics . co . uk/loc-manufacturing/foot-orthotics/ one can find a presentation of a CAD/CAM system for fabricating foot orthotic. The foot orthotics are machined only on the upper side, just as the previously mentioned Orthema machine.

The DE4404695A1 document (WALTER DIETMAR) teaches about a system for creating foot orthotics by means of a CNC machine on the basis of a 3D foot scan. According to the presented drawings, the machine uses one cutter to machine the workpiece. Therefore, the whole operation takes much more time than in the case of the said invention, at least two times. The system described in DE4404695A1, and realized in practice, has a special option for generating the bottom part of the insole. But, this procedure is rather clumsy as it includes the machining of 3/4 of the material to generate the bottom surface of the shoe insert, and then, the created block is glued to the base leather pattern. Then, it is secured again to the worktable to machine the upper side of the insole. Securing of the workpiece is achieved by using a vacuum table with a special mask which leaves free only the air intake holes located below the workpiece so that it can be fastened to the table. Due to the nature and properties of the basic materials that are machined (elasticity, porosity, significant degree of deformation at relatively small changes in temperature) , this approach often results in the workpiece being detached from the table, and the whole procedure has to be repeated. An alternative to using vacuum tables for secure fastening of the workpiece to the table is to fasten it by using adhesive tape. This requires additional time and material, not to mention the constant need for assistance of a CNC machine operator.

Regarding the design characteristics of the disclosed invention, we selected two important patent documents. The CN201871933 (U) document (HU ZHAO et al.) describes a CNC machine with a horizontal-milling setup, with cutters in collinear pairs, the same as in the said invention. The cutters are used to machine shaft ends, see Figures 1-3, but it seems that the pairs of cutters working on the left side of the workpiece move synchronously with those on the right side, meaning that cutters cannot move independently, as it is the case with the said invention. Furthermore, the workpiece carrier moves in only one direction, and the operation of the described machine is fully automated. On the other hand, each cutter of the disclosed invention is moved along the z-axis by independent drive, while the workpiece is moving in the x-y plane in order for the orthotics to be formed. The technical solution described in CN201871933 discloses solution where workpieces move along only one axis.

The WO2006/020819A1 document (DUNCAN ROD et al.) discloses the CNC machine with two separately controlled cutters placed opposite each other in a horizontal-milling setup. The cutters, used for the machining of dental crowns, can be controlled independently of each other, see Figure 2 in the document. The main difference between this machine and the said invention is in the size of the treated surface and in the way the workpiece is fastened (non-automated) . In the said example, the cutters are designed in a special way so that different types of machining can be performed, depending on which part of the cutter is used to machine the workpiece. In contrast, here disclosed invention has two pairs of cutters, placed opposite each other, which can be controlled independently of each other. The cutters are designed for only one type of machining - removal of the material. In addition, the disclosed invention has a device for automatic feeding of workpieces and unloading of finished products, which is not the case with the said CNC machine.

Summary of the invention

In order to solve the technical problems cited before, we disclose a machine for the manufacture of custom-made foot orthotics from blanks. These blanks are commercially available and have found their application with the machines listed in the art. The blanks are easily prepared in the way which is well known in the art and are packed in blocks of 10 or 20 pieces, which are in turn put into cassettes designed for this purpose.

The machine designed according to the invention consists of a frame with several supporting plates for supporting the CNC components. One or two cassettes with blanks are placed on the supporting plates .

The machine has a workpiece carrier with movable jaws for the clamping and releasing of workpieces. The motion of workpiece carrier along the x-axis of the machine is controlled by a horizontal feed drive and along the y-axis by a vertical feed drive. There are at least two pairs of opposing collinear cutters in a horizontal-milling setup to balance axial forces on both sides of the workpiece, or of a pair of workpieces fastened to the workpiece carrier. During the machining operation, the movement of each cutter along the z-axis is independent and in direction that is perpendicular to the workpiece.

Loading of blanks, clamping of the workpiece within the carrier and releasing of the machined workpiece/s is automated in the way that the operations of clamping and releasing of the jaws depend only on the y-coordinate position of the workpiece carrier in the frame. The movement of the workpiece carrier in the x-y plane is produced by servo motors. Each feed drive of the cutter has a separate servo motor which controls the movement . along the z-axis, i.e. the depth of cut of a particular cutter.

Clamping and releasing of the workpiece from the workpiece carrier is performed by two chain and sprocket assemblies and by two spindles, where each spindle having left and right thread. Rotations of spindles determine the distance between the movable jaws within the workpiece carrier as it moves along the y-axis. The chain and sprocket drive and its rotation direction, which determines the clamping and releasing of workpieces, are controlled by racks which turn on/off the drive.

The machine designed according to the said invention has a unit for chip sucking of the waste material produced by the machining of a workpiece/workpieces . The unit is designed according to well-known designs in the art. The only thing that is important is to enable also the sucking of micro particles (dust collecting) if the machine is to be used in medical institutions.

If one workpiece is machined, the final product is a pair of foot orthotics machined on the upper and the bottom side. The pair of foot orthotics is still connected to the remainder of the machined workpiece by means of tabs.

If two workpieces are machined simultaneously, two pairs of foot orthotics machined on the side turned to the user' s foot are produced . A brief description of figures

Figure 1 shows a machine for the manufacturing of custom-made foot orthotics. Figure 2 gives a view of the machine shown in Figure 1 from the angle that enables better identification of the element layout on the upper plate of the machine. Figure 3 presents details of the workpiece carrier with a clamping device, while a view from above of the same details is given in Figure 4.

Figure 5 presents a view of the machine for the manufacturing of custom-made foot orthotics where the directions of workpiece carrier movements are marked. Figure 6 shows a detail of the machine shown in Figure 5 from another angle so that the 3D layout of machine elements is clearly seen.

Figure 7 gives a schematic view of the machining of one workpiece from two opposite sides by means of four cutters, Figure 8 gives a schematic view of simultaneous machining of two workpieces, each from one side, by means of two pairs of cutters.

Figure 9 shows the way of the unloading of machined workpieces - finished products - from the machine for the manufacturing of custom-made foot orthotics. Figure 10 presents a machined workpiece treated on the upper and the bottom side with foot orthotics ready to be inserted into shoes.

A detailed description of the preferred embodiment

The preferred way ^'of the invention realization is presented in Figures 1-10. Figure 1 shows a CNC machine for the manufacturing of custom-made foot orthotics. Position (1.1) refers to the CNC machine frame which is realized as a metal structure capable of fixing and supporting all constituent parts of the machine. On the frame (1.1), there are supporting plates (1.2) with other CNC machine elements hung/placed on them. Cassettes (3.2) with blanks (3.11) are situated on the upper supporting plates (1.2), as shown in Figures 1 and 2. Beneath the upper supporting plates (1.2), there are two pairs of opposing feed drives (6.1) with spindle motors (6.2) fixed to them. Spindles with cutters (6.3) perform the machining of the fastened workpiece (3.12) or a pair of workpieces (3.12). Servo motors (6.9) control the feed drives (6.1) and also the independent position of each cutter (6.3) relative to the workpiece or workpieces (3.12) fastened in the workpiece carrier (2.1) with a clamping device.

In this text we use the following terms, depending on the stages in the machining process: blank (3.11) - for the element from which a new product is created till the stage when this element is fastened to the workpiece carrier (2.1). As soon as the blank (3.11) is within the workpiece carrier (2.1), then position (3.11) is referred to as workpiece (3.12). Upon the completion of the machining process, the workpiece (3.12) is called machined workpiece (3.13).

In the central part of the CNC machine, between two pairs of opposing feed drives (6.1), there is a workpiece carrier (2.1), the movements of which in the x-y plane can be controlled by means of a horizontal feed drive (4.1) and a vertical feed drive (5.1), see Figures 1 and 2. Feed motion is controlled and powered by the appropriate servo motors which are connected mechanically to the feed drives (4.1, 5.1).

The CNC machine is fully automated. The blanks (3.11) to be machined are put into frames -cassettes (3.2) - which can hold a number of blanks (3.11). The direction of the external forces applied to the blanks (3.11) to push them out from the cassettes (3.2) placed on both sides of the workpiece carrier (2.1), where they would be received and fastened, is shown in Figure 2 by means of arrows. External forces may be generated by any means, i.e. mechanically, electrically or pneumatically, in order to produce mechanical forces to the blanks (3.11) as known in the art. If the cassettes (3.2) are positioned on both sides of the workpiece carrier (2.1), they can be used in the case of simultaneous machining of two pairs of foot orthotics only on the upper side, i.e. one pair of workpieces (3.1) simultaneously in one CNC machine cycle. Another possibility is shown in Figure 1. Here, the cassette (3.2) with blanks (3.11) is placed on one side of the workpiece carrier (2.1). Such a configuration is suitable for the machining of only one workpiece on both of its sides (3.12), i.e. one pair of foot orthotics. Regardless of the configuration, the principle of the machine operation is the same. A force from an external source is applied to one end of the cassette (3.2). On the opposite end of the cassette, the one close to the workpiece carrier (2.1), there might be optionally a mechanical blank retainer which prevents or permits the movement of blanks (3.11) along the z-axis on the supporting plates (1.2) to the position of the workpiece carrier (2.1). Such technical solutions are already known in the art; therefore, it is not necessary to elaborate them further. Such solutions exclude the need for an operator in charge of loading the blanks (3.11) into the machine, as this is the case with the previously listed technical solutions in the "state of the art" section.

The central part of the CNC machine is the workpiece carrier (2.1) equipped with a clamping unit presented in detail in Figures 3 and 4. The workpiece carrier (2.1) has three important functions which make this invention inventive over the prior art. The workpiece carrier (2.1) is capable of:

- receiving and fastening one or two blankets (3.11),

- moving in the x-y plane during the machining of a workpiece/workpieces (3.12), and

- releasing the machined workpiece (3.13) from the CNC machine.

Receiving of the blanks (3.11) is carried out in the following way: by means of the horizontal feed drive (4.1) and the vertical feed drive (5.1), the workpiece carrier (2.1) is raised to the position in which its upper edge is levelled with the supporting plates (1.2) on which blanks (3.11) slide. As the workpiece carrier rises, the movable jaws (2.3) open to enable the gripping of one or two blanks (3.11), depending on the selected machining procedure. The blanks (3.11) are pushed by the external force and pass by the unlocked blank holder - if it is realized - to enter, or better to say to drop (due to the action of gravity) - into the space designed for that purpose between movable jaws (2.3) in the workpiece carrier (2.1). When the workpiece carrier (2.1) stars its downward movement on four guides (2.6) with slides (2.7) on the workpiece carrier (2.1), the movable jaws close (2.3). Thus, the movable jaws fasten one workpiece (3.12) or two workpieces (3.12) to the workpiece carrier (2.1). The clamping force is controlled by the clamping of movable jaws (2.3) performed only on one section of the downward path of the workpiece carrier (2.1) along the y-axis.

The solution described above is realized by racks with teeth distributed only on the path section of the workpiece (2.1) movement along the y-axis where these racks are not shown in the figures. The function of racks is to turn on or turn off the chain and sprocket (2.4) drive placed on the both sides of the workpiece carrier (2.1). Using chain ^'and sprocket (2.4) drive with two spindles (2.5), equipped with the appropriate left and right thread, and connected to the movable jaws, control the degree of clamping or, better said, the degree of openness or closeness of the movable jaws (2.3). The above mentioned racks . determine the movement direction of chains with sprockets (2.4), which determines either the opening or the closing of movable jaws (2.3). The assembly is designed in the way that the movable jaws (2.3) become increasingly more open as they rise, and increasingly more closed as they descend.

In Figure 3, the descending path of the workpiece carrier (2.1) in the direction of y-axis is shown by an arrow. As the workpiece carrier descends, the inner part of movable jaws (2.3) move in the way to push the workpieces (3.12) toward the outer sides and thus to fasten them within the assembly (2.1), see arrows in Figures 3 and 4. It should be pointed out here that the workpieces are made of a soft material; therefore, possible more intensive or less intensive clamping has no effect on the material or on the functionality of the workpiece carrier (2.1). It is advisable to install a safety device, e.g. a mechanical device that would prevent the clamping of movable jaws (2.3) beyond a recommended clamping force. Such devices are well known in the art; and henceforth will not be discussed here .

Once the workpieces (3.12) are fastened within the movable jaws (2.3) of the workpiece carrier (2.1), they are ready to be machined. Machining is performed by the movement of the assembly (2.1) in the x-y plane within the section of the y-axis in which the previously mentioned racks do not control the operations of clamping or releasing of movable jaws (2.3), as shown by arrows in Figure 5.

The movement of workpiece carrier (2.1) along the y-axis is controlled by the vertical feed drive (5.1) powered by a servo motor (5.9), sliding by means of the slides (2.7) on vertical guides (2.6). The horizontal feed drive (4.1) powered by a servo motor (4.9) controls the movement along the x-axis. Since the considered assembly has substantial mass, the assembly (2.1) slides by means of its horizontal slide (2.2) on the horizontal guide (4.2) to reduce machining errors. Thus, the system of four vertical guides (2.6) and a horizontal guide (4.2) determines the position of the workpiece carrier (2.1) during the machining of a workpiece (3.12) or workpieces (3.12). The spatial arrangement of CNC machine elements in machining can be clearly seen in Figure 6, except for the previously mentioned guides (2.6) which are completely incorporated in the slide (2.7) .

Servo motors (6.9) propel the feed drives (6.1) which control the spatial position of the main spindle motor (6.2), and thus the position of cutters (6.3) relative to the surfaces of the workpiece (3.12), see Figure 6. Figure 7 gives a schematic view of machining one workpiece (3.12) on both sides in order to obtain a pair of foot orthotics machined on the upper side, i.e. the side turned to the foot, and on the bottom side - the side turned to the shoe. As previously mentioned, the workpiece (3.12) moves in the x-y plane, while each of the cutters (6.3) - here marked as {zl, z2, z3, z4} - removes independently the required amount of material from the workpiece (3.12). Main spindle motors (6.2) have to produce adequate power for performing machining. Experience has shown that the installed power of 1.5 kW of the main spindle motor (6.2) is sufficient for the successful and reliable operation of such a machine .

Figure 8 presents the case of simultaneous machining of two workpieces (3.12) where each of the workpieces (3.12) is machined on only one side, resulting in two pairs of foot orthotics machined on the side turned to the foot. The foot orthotics obtained in that way subsequently need to be manually adapted to the user' s shoes by treating the bottom side turned to the shoe.

It should be noted that servo motors (4.9) and (5.9) that control the movement of the workpiece carrier (2.1) in the x-y plane and the set of servo motors (6.9) that control the positions of cutters (6.3) along the z-axis are all controlled by an external controller connected to a computer. The technical problem not discussed here refers to sampling of the user' s 3D foot contours and the conversion of a cloud of points into optimized paths of such a 6-axis CNC machine, where the axes of the said machine are {x, y, zl, z2, z3, z4}. This problem is algorithm related and out of the scope of constructing the machine for manufacturing custom-made foot orthotics, which is the object of the said invention.

In practice, the option of machining one workpiece (3.12) to produce a machined workpiece (3.13) with a pair of foot orthotics, machined to the degree where additional intervention is not required, will be the most widely used option. Also, it is very simple to imagine a machine which operates in the same way, but with 4n z-axes (n is an integer), where these axes have equivalent cutters (6.3) for the workpiece machining. This enables simultaneous manufacturing of, for example, two or three pairs of foot orthotics simultaneously machined on the both sides. When the machining of one or two workpieces (3.12) is completed, the further downward movement of the workpiece carrier (2.1) in the direction of y-axis release machined workpiece (3.13). Namely, below a particular y coordinate, results that the rack with its teeth turns on the mechanism consisting of chains and sprockets (2.4) and a spindle, which now releases the machined workpieces (3.13) from the movable jaws (2.3), as shown by arrows in Figure 9.

The result of such a process of machining is a machined workpiece (3.13) which is - in the case of one workpiece (3.12) - machined on the both sides, as shown in Figure 10. The pair of foot orthotics (3.3) obtained in that way is connected to the machined workpiece (3.13) by means of tabs (3.4) that can be easily broken. Thus, the first technical problem of manufacturing a pair of foot orthotics not requiring further treatment has been solved. If two workpieces (3.12) are machined, as shown in Figure 8, the result of machining are two pairs of foot orthotics, with each pair machined only on the upper side, i.e. the side turned to the foot. In that case, there is a need for further manual treatment of such an intermediate product to adapt it the shoe. Thus, the second technical problem is solved.

The solution to the third technical problem - balancing of axial forces along the z-axis - follows from the very design of the machine. Polymeric materials used for blanks (3.11) are relatively flexible. Forces generated by cutters (6.3) which are arranged in opposing collinear pairs compensate possible shift of workpiece (3.12) from the cutter (6.3) during the machining process. This fact enables the machining of workpiece (3.12) with accuracies of up to 0.1 mm as if the workpiece (3.12) constantly adhered to a solid surface by one of its sides - which is really the case with some machines previously presented in the art.

The workpiece (3.12) is placed in the x-y plane of the machine. The chips of the material removed by rotating cutters (6.3) fall in the direction of the y-axis due to the action of gravity. That way, it is very easy to gather the waste material by a unit for chip sucking (dust collecting) , and the removed chips do not interfere with the operation of cutter (6.3) . This solves the third and the fourth technical problem.

The process of automatic loading of blanks and automatic unloading of machined workpieces upon the completion of machining has been already described. This process efficiently solves the fifth technical problem omnipresent in the technical solutions presented in the solutions related to prior art. In the disclosed embodiment there is no need for an assistant that would fasten the blank, release the workpiece and unload the machined workpiece from the CNC machine .

A disclosed invention in the form of a prototype has been tested at the Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb. It has been shown that the average time required for the manufacturing of a pair of foot orthotics, according to the specification from the first technical problem, is less than 6 minutes. This solves the last technical problem.

Indeed, such a machine is capable of manufacturing foot orthotics upon the user's request in a very short time according to the sampling of the 3D foot image, with a fully automated design and generation of tool paths for a 6-axis CNC machine.

An expert in the field immediately understands that the capacity of such CNC machine can be enhanced if generally 2+4n CNC axes are used, n≥l, resulting in the creation of 2n individual foot orthotics, or n pairs of foot orthotics, to be more precise. Furthermore, additional modifications to this machine are possible, apart from the described increase in the machine capacity by increasing the number of spindles that perform machining. An obvious modification can be made to the workpiece carrier (2.1) where- the holding and releasing of workpieces (3.12) can be performed by other means than mechanical, for example by some pneumatic processes or even electrostatic processes. However, such solutions exhibit some other weaknesses in practice or make the machine more expensive without increasing the reliability of the machining operations.

Industrial applicability

The said invention has undoubted industrial applicability as a fully automated machine for manufacturing custom-made foot orthotics, capable of solving technical problems observed in the previously presented state of the art, cited in this description.

List of references

1.1 - CNC machine frame

1.2 - supporting plates

2.1 - workpiece carrier

2.2 - slide

2.3 - movable jaws

2.4 - chain and sprocket

2.5 - spindle

2.6 - guide

2.7 - slide

3.11 - blank

3.12 - workpiece

3.13 - machined workpiece

3.2 - cassette with blanks

3.3 - foot orthotics

3.4 - tabs

4.1 - horizontal feed drive

4.2 - guide

4.9 - servo motor of horizontal feed drive 4.1

5.1 - vertical feed drive

5.9 - servo motor of vertical feed drive 5.1

6.1 - feed drive

6.2 - main spindle motor

6.3 - cutter

6.9 - servo motor of feed drive 6.1

Claims

A machine for manufacturing custom-made foot orthotics (3.3) from blanks (3.11), which consists of a frame (1.1) with supporting plates (1.2) for machine elements, with cassettes (3.2) on the supporting plates (1.2) in which there are blanks (3.11) that are pushed by the action of external force to the position where they can be received by the workpiece carrier (2.1), characterized by that:

- the machine possesses a workpiece carrier (2.1) with movable jaws (2.3) for the clamping of workpieces (3.12), where the workpiece carrier (2.1) makes controlled movements along the x-axis by means of a horizontal feed drive (4.1) and along the y-axis by means of a vertical feed drive (5.1);

- where the machine has at least two additional horizontal feed drives (6.1) with motors of main spindles (6.2) and cutters (6.3) placed collinearly on the both sides of the workpiece (3.12) or a pair of workpieces (3.12) to balance axial forces being fastened in the workpiece carrier (2.1), where each cutter (6.3) can be moved along the z-axis perpendicularly to the workpiece (3.12) and independently of other cutters while perform machining; and

- where the loading of blanks (3.11), clamping of workpieces (3.12) within the workpiece carrier (2.1) and the unloading of the machined workpiece (3.13) are automated in the way that the closing or opening of the movable jaws (2.3) depend on the y position of the workpiece carrier (2.1) within the frame (1-1) .

The machine for manufacturing custom-made foot orthotics according to claim 1, characterized by that the drives (4.1, 5.1) for the workpiece carrier (2.1) movement in the x-y . plane are controlled by servo motors (4.9, 5.9), and that each feed drive (6.1) has its own servo motor (6.9) which controls the depth of cut in the machining of the workpiece (3.12) by a cutter (6.3) in the direction of z-axis. The machine for manufacturing custom-made foot orthotics according to any of previous claims, characterized by that the clamping and releasing of the machined workpieces (3.13) from the workpiece carrier (2.1) is performed by two chain and sprocket

(2.4) assemblies and two spindles (2.5), where each spindles

(2.5) having left and right thread, where rotations of spindles (2.5) determine the openness of movable jaws (2.1) within the workpiece carrier (2.1) while the workpiece (2.1) is moving along the y-axis, and where the chain and sprocket (2.4) drive and their direction of rotation, that determines the clamping or releasing of the workpiece (3.12), is controlled by the racks that turn on or off the said chain and sprocket assembly.

The machine for manufacturing custom-made foot orthotics according to any of previous claims, characterized, by that it possesses a unit for chip sucking of scrap material produced in the machining of workpiece (3.12) .

The machine for manufacturing custom-made foot orthotics according to any of previous claims, characterized by that the machining of one workpiece (3.12) results in a machined workpiece (3.13) consisting of a pair of foot orthotics (3.3), machined on the upper and bottom sides, which are still connected to the remainder of machined workpiece by tabs (3.4) .

The machine for manufacturing custom-made foot orthotics according to any of previous claims, characterized by that the simultaneous machining of two workpieces (3.12) results in the final product of two pairs of foot orthotics (3.3) machined only on the upper side.