MACHINE TOOL

Abstract

The machine tool includes a workpiece carrier assembly arranged for horizontal movement in parallel to a horizontal axis and a tool carrier configured for carrying at least one tool for machining at least one workpiece by rotating the tool. The workpiece carrier assembly or the tool carrier is displaceable between an operative position in which a workpiece carrier is facing the tool carrier, and at least one inoperative position. The workpiece carrier is arranged to be rotatable to allow for a modification of the angular position of the workpiece in relation to the tool carrier.

Claims

1. A machine tool comprising: a workpiece carrier assembly including a workpiece carrier for supporting at least one workpiece; a workpiece carrier support, the workpiece carrier assembly being supported on the workpiece carrier support for horizontal movement in a first direction on the workpiece carrier support, said first direction being parallel to a horizontal X axis; a tool carrier configured for carrying at least one tool for machining at least one workpiece by rotating said tool; a tool carrier support, said tool carrier being supported on said tool carrier support for horizontal movement in a second direction on said tool carrier support, said second direction being parallel to a horizontal Z axis, said Z axis being perpendicular to said X axis; wherein said workpiece carrier assembly is displaceable on said workpiece carrier support in said first direction between an operative position in which said workpiece carrier is facing said tool carrier, and at least one inoperative position in which said workpiece carrier is not facing said tool carrier; wherein the workpiece carrier is arranged to be rotatable around an axis parallel to the X axis, to allow for a modification of the angular position of the workpiece in relation to the tool carrier; and wherein the workpiece carrier comprises at least one workpiece support area for supporting said at least one workpiece, said workpiece support area being arranged substantially in parallel to the X axis.

2. The machine tool according to claim 1 wherein, when the workpiece carrier assembly is in said inoperative position, the tool carrier is displaceable to a tool change position overlapping with the position in which the workpiece carrier is placed when the workpiece carrier assembly is in the operative position.

3. A machine tool comprising: a workpiece carrier assembly including a workpiece carrier for supporting at least one workpiece; a workpiece carrier support, the workpiece carrier assembly being supported on the workpiece carrier support for horizontal movement in a first direction on the workpiece carrier support, said first direction being parallel to a horizontal Z axis; a tool carrier configured for carrying at least one tool for machining at least one workpiece by rotating said tool; a tool carrier support, said tool carrier being supported on said tool carrier support for horizontal movement in a second direction on said tool carrier support, said second direction being a direction in parallel to a horizontal X axis, perpendicular to said horizontal Z axis; wherein said tool carrier is displaceable on said tool carrier support in said second direction between an operative position in which said workpiece carrier is facing said tool carrier, and at least one inoperative position in which said workpiece carrier is not facing said tool carrier; wherein the workpiece carrier is arranged to be rotatable around an axis parallel to the X axis, to allow for a modification of the angular position of the workpiece in relation to the tool carrier; and wherein the workpiece carrier comprises at least one workpiece support area for supporting said at least one workpiece, said workpiece support area being arranged substantially in parallel to the X axis.

4. The machine tool according to claim 3, comprising at least one additional tool carrier configured for carrying at least one tool for machining at least one workpiece by rotating said tool, each of the tool carriers being displaceable on the tool carrier support in the second direction between an operative position in which the workpiece carrier is facing the respective tool carrier, and at least one inoperative position in which the workpiece carrier is not facing the respective tool carrier.

5. The machine tool according to claim 3, wherein said tool carrier is configured for carrying said at least one tool for machining said at least one workpiece by rotating said tool around an axis parallel to said Z axis.

6. The machine tool according to claim 3, wherein the workpiece carrier includes, in the workpiece support area, means for holding a plurality of workpieces, arranged one after the other in a row extending in parallel to the X axis.

7. The machine tool according to claim 3, wherein said workpiece carrier comprises at least two workpiece support areas, each of said workpiece support areas being arranged for supporting at least one workpiece, said workpiece support areas being placed so that by rotating the workpiece carrier around said axis parallel to the X axis, one of said workpiece support areas can selectively be brought to a position for loading and unloading, whereas another one of said workpiece support areas is brought to a position substantially facing the tool carrier.

8. The machine tool according to claim 7, wherein said workpiece carrier comprises more than two of said workpiece support areas.

9. The machine tool according to claim 3, further comprising an auxiliary support for supporting the workpiece carrier, the workpiece carrier assembly and the auxiliary support being arranged so that at least one of them can be displaced, towards the other one for interconnection between the workpiece carrier and the auxiliary support, and from the other for disconnection between the workpiece carrier and the auxiliary support, so as to allow the workpiece carrier to be supported by the auxiliary support during machining, while being rotatable around said axis parallel to the X axis, supported between the workpiece carrier assembly and the auxiliary support.

10. The machine tool according to claim 9, wherein said auxiliary support and said workpiece carrier are provided with means for interconnection comprising a projecting member and a recess, the projecting member being arranged to fit into the recess.

11. The machine tool according to claim 3, wherein the workpiece carrier comprises means for holding workpieces, said means for holding workpieces being mounted on rotatable supports for rotating the workpieces around an axis perpendicular to said X axis.

12. The machine tool according to claim 3, wherein the workpiece carrier support and the tool carrier support together have an L configuration, when viewed from above, and/or wherein the workpiece carrier is mounted on the workpiece carrier assembly so that the workpiece carrier is displaceable in the vertical direction, and/or wherein the workpiece carrier support and the tool carrier support are placed on a floor and arranged to support the workpiece carrier assembly and the tool carrier, respectively, from below.

13. The machine tool according to claim 12, wherein, when said tool carrier is in said tool change position, said tool carrier is situated adjacent to and facing, along the Z axis, an opening in an enclosure of the machine tool, and wherein said machine tool optionally includes a door in said opening of the enclosure.

14. the machine tool according to claim 12, wherein the workpiece carrier is configured for supporting at least one workpiece for producing a connecting rod.

15. A method for machining workpieces, such as rod blanks for manufacturing connecting rods for reciprocating piston engines, the method including the following steps: subjecting each workpiece to a plurality of machining steps, wherein a plurality of the machining steps are performed by a machine tool according to claim 1, and rotating the workpiece carrier around an axis parallel to the X axis between at least two of said machining steps.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0065] To complete the description and in order to provide for a better understanding of the disclosure, a set of drawings is provided. Said drawings form an integral part of the description and illustrate embodiments of the disclosure, which should not be interpreted as restricting the scope of the disclosure, but just as examples of how the disclosure can be carried out. The drawings comprise the following figures:

[0066] FIGS. 1A-1D schematically illustrate some operations which can be carried out when machining a connecting rod out of a rod blank, involving the use of different tools;

[0067] FIG. 2 is a side view of a machine tool according to one possible embodiment of the disclosure;

[0068] FIGS. 3A-3C are top views of the machine tool in accordance with said embodiment of the disclosure, in three different states;

[0069] FIGS. 4A-4D are perspective views of a different embodiment, based on a general layout similar to the one of FIGS. 2-3C;

[0070] FIGS. 5A-5B are top views of the machine tool in accordance with another embodiment, in two different states;

[0071] FIGS. 6A and 6B are perspective views of another embodiment, based on a general layout similar to the one of FIGS. 5A and 5B;

[0072] FIG. 7 is a perspective view of a variant of the embodiment illustrated in FIGS. 6A and 6B;

[0073] FIGS. 8A and 8B are perspective views of another embodiment;

[0074] FIGS. 9A-9D are perspective views of yet another embodiment; and

[0075] FIGS. 10A and 10B are top views of additional embodiments.

DETAILED DESCRIPTION OF THE DISCLOSURE

[0076] FIG. 2 shows a machine tool according to one possible embodiment of the disclosure, from the side, that is, viewed in parallel with a horizontal X axis perpendicular to the horizontal Z axis and the vertical Y axis of the system. The machine tool comprises a tool carrier 2, such as a tool carrier carriage, moveable on rails 22 (one of which is shown in FIG. 2) or other suitable guide means, forming part of a tool carrier support 21. The movement of the tool carrier 2 is in the horizontal direction, in parallel with the Z axis of the system. The movement can be generated by a computer controlled drive system using one or more servomotors or other drive means (the drive means are not illustrated in FIG. 2). The tool carrier can comprise spindles and spindle heads, as known in the art, to rotate corresponding tools 204, 208, 212 around their axis of rotation, parallel with the Z axis. The operation of the tools can be computer controlled. In some embodiments of the disclosure, the individual tools can be arranged to be individually displaceable, for example, under the control of a computer, in parallel with the Z axis, so as to act on a corresponding workpiece. In other embodiments of the disclosure, the tools are fixed in relation to the tool carrier, so that the entire tool carrier has to be displaced to move the tool in relation to the workpiece, along the Z axis. In some embodiments of the disclosure, one or more of the tools can be arranged to rotate around an axis not parallel with the Z axis.

[0077] In the embodiment of the disclosure illustrated in FIG. 2, the tool carrier is arranged to hold a plurality of different tools, and arranged to operate so that during machining of one workpiece, different tools are applied to the workpiece to carry out different machining operations, simultaneously or at different stages of the process. In some embodiments of the disclosure, at one or more stages of the process more than one tool can be applied to a workpiece simultaneously, and/or a plurality of workpieces can be machined simultaneously, such as in parallel with each other.

[0078] The machine tool further comprises a workpiece carrier assembly 1 including a workpiece carrier 11 including means 110 for holding workpieces. These means 110 for holding workpieces are arranged on two opposite surfaces or workpiece support areas 11A and 11B of the workpiece carrier. In the state of the machine tool illustrated in FIG. 2, one of these workpiece support areas 11A is facing the tool carrier 2 along the Z axis of the system, and the other of these workpiece support areas 11B is facing in the opposite direction. Thus, in this state of the machine, and when the workpiece carrier is placed in front of the tool carrier 2 along the Z axis, the tools of the tool carrier can act on the workpieces supported in correspondence with workpiece support area 11A, whereas already machined workpieces can be unloaded and workpieces to be machined can be loaded in correspondence with the workpiece support area 11B. That is, machining of the workpieces at one of the two workpiece support areas can take place while unloading and loading is taking place at the opposite workpiece support area.

[0079] In the illustrated embodiments, two workpieces can be arranged in each of the two support areas 11A and 11B; the workpieces can be arranged vertically, one beside other. However, in other embodiments of the disclosure, they can be arranged horizontally, or in any other suitable orientation. In some embodiments of the disclosure, the workpiece carrier is arranged for holding only one single workpiece in each workpiece support area. In some embodiments of the disclosure, the number of workpieces in each workpiece support area matches the number of tools in the tool carrier, or the number of tools in a row of tools in the tool carrier. In some embodiments of the disclosure, there is only one area provided for holding workpieces, and machining has to be interrupted during loading and unloading.

[0080] The workpiece carrier is arranged on a carriage 13 (not shown but marked as a square with dotted lines in FIG. 2; illustrated in FIGS. 3A-3C) which is displaceable along the vertical Y axis, on a tower structure 14, for example, along rails 15, driven by one or more computer controlled servomotors or other suitable drive means. On the other hand, this tower structure 14 is arranged to be displaced along the horizontal X axis, perpendicular to the horizontal Z axis, on horizontal rails 16 (shown in FIGS. 3A-3C) forming part of the workpiece carrier support 12. The tower structure 14 can be driven in parallel with/along the X axis by one or more computer controlled servomotors, or other suitable drive means.

[0081] In FIGS. 2 and 3A-3C, arrows indicate the directions in which the tool carrier 2, workpiece carrier 11 and workpiece carrier assembly 1 (including the tower structure 14) are displaceable by the (not illustrated) drive means. On the other hand, and as schematically illustrated in FIG. 2, the workpiece carrier 11 is joined to the vertically displaceable carriage 13 by a shaft 17 (illustrated in FIGS. 3A-3C) or other means of interconnection between the workpiece carrier and the carriage, so as to allow for controlled tilting, pivotation or rotation of the workpiece carrier, around the X axis. That is, the workpiece carrier 11 is connected to the carriage 13 by means 17 that allow for controlled tilting, pivotation or rotation of the workpiece carrier 11, around or with regard to the X axis. This movement can be carried out by one or more computer controlled servomotors, or by any other suitable controllable drive means. By means of this additional degree of freedom of movement, the workpiece or workpieces can be oriented so as to provide for a suitable angle of attack between tool and workpiece, and this angle can be modified during machining of a workpiece so that a sequence of different machining operations can be carried out on the workpiece, under different angles of attack, without modifying the orientation of the axes of the tools and without changing the position of the workpiece with regard to the workpiece carrier as such. That is, a wide range of operations can be carried out on the workpiece by moving the workpiece in parallel with the horizontal X axis (by displacing the tower structure 14 along the tracks 16), in parallel with the vertical Y axis (by displacing the carriage 13 along the tracks 15), and by tilting, pivoting or rotating the workpiece carrier 11 around the X axis (for example, by means of turning the shaft 17 around its longitudinal axis), and by displacing individual tools and/or the entire tool carrier 2 in parallel with the Z axis, along the corresponding tracks 22. In FIGS. 3A-3C the shaft 17 is visible between the carriage 13 and the workpiece carrier 11, but this is just to illustrate the rotatable connection between the workpiece carrier 11 and the carriage 13; in many embodiments of the disclosure, the shaft will not be visible, and in other embodiments of the disclosure there is no such shaft, but the workpiece carrier is connected to the carriage 13 by other means that allow for rotation.

[0082] As illustrated in FIG. 2, the tools can be arranged at different heights in the tool carrier 2, for example, in several rows, and each row can include one or more tools. For example, in FIGS. 3A-3C an embodiment is shown where the top row of the tool carrier includes four tools.

[0083] Some of the tools may be different, in order to carry out different operations on a workpiece. In some embodiments of the disclosure, machining operations are arranged to take place on two or more workpieces simultaneously, at least at one or some of the stages of machining of the workpieces. However, in some embodiments of the disclosure, only one workpiece is being machined at each moment. This can simplify the structure and programming of the machine tool, but also imply a lower production rate. In some embodiments of the disclosure, two or more operations can be carried out simultaneously on one workpiece or on each of a plurality of workpieces, that is, two or more tools can be operating simultaneously on a workpiece or on each of a plurality of workpieces. In some embodiments of the disclosure, each tool or at least some of the tools can be associated with drive means that allow for a longitudinal displacement of the tool in parallel with the Z axis, so that its position along the Z axis can be independent, at least to a certain extent, of the position along the Z axis of one or more of the other tools. This can serve to enhance flexibility and productivity. By displacing the workpiece in parallel with the X and Y axes, the workpiece can be displaced so that different tools can operate on different portions of the workpiece, and by rotating or tilting the workpiece assembly around the X axis, the angle of attack can be set in accordance with the operation to be performed. Thus, a very large number of different operations can be carried out, using different tools. In some embodiments of the disclosure, the tools are sufficiently spaced from each other (for example, in terms of the separation between different tools in a row and/or in terms of separation between rows) so that there is no undesired interference between tools and workpiece, that is, so that the workpiece can be brought into contact with a desired tool for carrying out a desired operation, without entering into contact with adjacent tools, even in the absence of any possibility of (individual) displacement of one tool with regard to the other tools, along the Z axis. In some embodiments of the disclosure, at least some tools are placed so close to each other that at least two tools can operate on the workpiece simultaneously.

[0084] FIGS. 3A-3C illustrate three different states of the machine tool of FIG. 2. In FIG. 3A, the workpiece carrier assembly 1 including tower structure 14, carriage 13, connecting means 17 and workpiece carrier 11 is placed in its inoperative position. The tool carrier 3 is placed away from the front end of the machine, that is, it is placed towards the rear of the tool carrier support 21, thereby allowing the workpiece carrier assembly 1 to move to its operative position, shown in FIG. 3B. In FIG. 3B, the workpiece carrier assembly is in its operative position, in which the workpiece carrier 11 faces the tool carrier 2 along the Z axis, thereby making it possible for the tools (the upper row of tools 201-204 being shown in FIG. 3B) to access the workpiece (or workpieces) 1000 held at the workpiece support area 11A, and to carry out machining operations in correspondence with predetermined positions of said workpiece and under predetermined angles of attack, by displacing the workpiece carrier along the X and Y axes and by tilting or rotating it around the X axis and, optionally, by displacing the tool carrier 2 and/or individual tools along the Z axis. At the same time, workpieces can be unloaded and/or loaded at the opposite workpiece support area 11B of the workpiece carrier 11.

[0085] FIG. 3C shows a third state of the machine tool, in which the workpiece carrier assembly 1 has returned to its inoperative position, allowing the tool carrier to move forward to occupy the space previously occupied by at least part of the workpiece carrier assembly 1 (for example, by the workpiece carrier 11), at the front end of the machine. Here, in a tool change position of the tool carrier, tools can be treated or exchanged and/or other maintenance operations can be carried out at the front end of the tool carrier 2, under ergonomically favourable conditions and without any need for the operator to squeeze in between tool carrier 12 and workpiece carrier 11. When in the tool change position, the tool carrier can be facing a door 31 in an enclosure 3 of the machine tool.

[0086] FIGS. 4A-4D schematically illustrate an alternative machine tool based on the general layout of FIGS. 2-3C. Here, the tool carrier features only two rows of tools. FIG. 4A illustrates the workpiece carrier assembly in the inoperative position. In this figure, one can see how the workpiece support area 11B extends in parallel with the X axis (the same is true for the opposite workpiece support area 11A, shown in FIG. 4B), and how four workpieces 1000 are arranged in the workpiece support area with their longitudinal axes perpendicular to the X axis, one workpiece beside the other in a row extending in parallel with the X axis. FIGS. 4B and 4C illustrate the machine tool from two different angles when the workpiece carrier assembly is in the operative position, so that the tools can interact with the workpieces. FIG. 4D illustrates the machine tool with the tool carrier in the tool change position.

[0087] FIGS. 5A and 5B illustrate an alternative embodiment of the disclosure. The tool carrier 2 and the workpiece carrier assembly 1 are of the same type as those of the embodiment of FIGS. 2 and 3A-3C, but the way in which they are arranged to move is different. In this embodiment, the tool carrier is arranged to be displaced in parallel with the X axis, between an operative position (FIG. 5A) in which it faces the workpiece carrier so that the tools can act on the workpiece or workpieces carried at the support area 11A, and an inoperative position (FIG. 5B) in which the tool carrier 2 and the tools are no longer facing the workpiece carrier 11, thereby allowing access to the tools from the front side of the tool carrier (for example, through a door 31 in an enclosure 3 of the machine tool), without the operator having to enter the space between workpiece carrier and tools. For adapting the distance between workpieces and tools along the Z axis, the workpiece carrier assembly can be displaceable in parallel with the Z axis, and/or tools or groups of tools can be displaced in parallel with the Z axis. A large number of machining operations can thus be performed by displacing the tool carrier 2 in parallel with the X axis and by displacing the carriage 13 in parallel with the Y axis, by displacing tools and/or the workpiece carrier assembly 1 in parallel with the Z axis, and by tilting, rotating or pivoting the workpiece carrier 11 around an axis parallel with the X axis.

[0088] FIGS. 6A and 6B illustrate a variant of the embodiment illustrated in FIGS. 5A and 5B. FIG. 6A illustrates the machine tool during operation, the tools facing the workpieces, and FIG. 6B illustrates the machine tool with the tool carrier in a tool change position. In this variant, the workpiece carrier features four workpiece support areas 11A-11D, each corresponding to one of the sides of a generally parallelepipedal workpiece carrier body. With this arrangement, and using a clockwise rotation of the workpiece carrier 11 for switching between machining one set of workpieces and machining a new set of workpieces, the last set of workpieces to have been machined will be positioned downwards, corresponding to the position of workpiece support area 11D (the one opposite workpiece support area 11C) in FIGS. 6A and 6B, before arriving at the position for loading and unloading, occupied by workpiece support area 11B in FIGS. 6A and 6B. One advantage of this solution is that this can be useful for the removal of remains from the machining operations, typically metal chips, from the workpieces, by gravity and possibly also due to vibration, while other workpieces are being machined. That is, in the state of the machine tool illustrated in FIG. 6A, while the workpieces at workpiece support area 11A are being machined, and while unloading or loading can be taking place at workpiece support area 11B, chips may fall down from the recently machined workpieces placed at workpiece support area 11D.

[0089] FIG. 7 illustrates an alternative embodiment according to which the workpiece carrier 11 features eight workpiece support areas, corresponding to the sides of a workpiece carrier body having an octagonal cross section.

[0090] FIGS. 8A and 8B illustrate an embodiment with a basic layout in line with the one of FIGS. 4A-4D, but with a different workpiece carrier: here, the workpiece carrier is provided with rotatable platforms or supports 130, so that the workpieces 1000, in addition to turning around the X axis due to rotation of the workpiece carrier, can be turned around an axis perpendicular to said X axis, thereby further enhancing versatility and increasing the number of operations that can be carried out using a given orientation of the tools and spindles. The workpiece carrier 11 is additionally provided with a recess 120, which can be useful if an auxiliary support is incorporated, as explained below in relation to FIGS. 9A-9D.

[0091] FIGS. 9A-9D illustrate a machine tool having a basic layout similar to the one of FIGS. 4A-4D, but with four workpiece support areas distributed according to the four sides of the parallelepipedal workpiece carrier body, and further including an auxiliary support 4. In the illustrated embodiment, the auxiliary support 4 is a stationary support, which includes a vertically moveable sledge 41 on which an engagement pin 42 is mounted. This pin is engaged to fit into the recess 120 of the workpiece carrier 11. In FIG. 11A, the machine tool is shown with the workpiece carrier assembly 1 in the inoperative position, and the tool carrier 2 in the tool change position, at the front end of the machine tool. Here, the workpiece carrier 11 is only supported on the workpiece carrier assembly, overhanging from the tower structure 14. FIG. 9B is a perspective view of the machine tool with the parts positioned as in FIG. 9A, but from a different angle, showing the recess 120 arranged to mate with the pin 42 of the auxiliary support.

[0092] Once the tool carrier 2 has moved back from the tool change position, the workpiece carrier assembly 1 is shifted in parallel with the X axis towards the operative position, approaching the auxiliary support 4. The position of the sledge 41 in the vertical direction is synchronised with the position of the tool carrier 11 in the vertical direction, so that the pin 42 can enter the recess 120, whereby the workpiece carrier 11 will be supported both on the tower structure 14 and carriage 13 of the workpiece carrier assembly 1, and on the auxiliary support 4, while being able to rotate around the X axis. This double support, at two sides of the workpiece carrier 11, can be useful to increase stability of the workpiece carrier during machining, and also to reduce the stresses and bending moments exerted on the tower structure 14 and carriage 13 when the machine tool is to remain idle for a substantial amount of time.

[0093] FIG. 10A illustrates an embodiment similar to the one of FIGS. 5A and 5B, but with an additional tool carrier 2A, displaceable on the tool carrier support 21 in parallel with the X axis. The tool carrier 2 is displaceable between the inoperative position A where it is not facing the workpiece carrier 11, and the operative position B where it is facing the workpiece carrier 11. Similarly, the additional tool carrier 2A is displaceable between the inoperative position C where it is not facing the workpiece carrier 11, and the operative position B where it is facing the workpiece carrier 11. Maintenance operations can be carried out on the additional tool carrier 2A or on its tools through the door 31, when the additional tool carrier 2A is in the inoperative position C. In what regards the tool carrier 2, maintenance may be slightly more laborious, but one option can be to move the workpiece carrier assembly 1 away from the tool carrier 2 along the X axis, and then access the space between, for example, the workpiece carrier 11 and the tool carrier 2 when the tool carrier is in the operative position B, for example. Another solution can be to extend the tool carrier support 21 establishing a further inoperative position beyond position A, to which the tool carrier 2 can be displaced when an operator desires to access the tool carrier for maintenance.

[0094] FIG. 10B illustrates an alternative embodiment, similar to the one of FIG. 10B but with a further inoperative position D added beyond position C. Also, a further door 31A has been added. Thus, as illustrated in FIG. 10B, the tool carrier 2 can be serviced through the door 31 when in the inoperative position C, and the tool carrier 2A can be serviced through door 31A when the tool carrier 2A is in the inoperative position D. Of course, in other embodiments of the disclosure, even more tool carriers can be used.

[0095] On the other hand, the disclosure is obviously not limited to the specific embodiment(s) described herein, but also encompasses any variations that may be considered by any person skilled in the art (for example, as regards the choice of materials, dimensions, components, configuration, etc.), within the general scope of the disclosure.